install-squid-proxy-debian.sh

#!/bin/bash

clear

# YOU NEED TO CUSTOMIZE EACH VARIABLE BELOW WITH YOUR OWN VALUES TO OPTIMIZE SQUID'S PERFORMANCE
# YOU CAN ADD, REMOVE, OR MODIFY THIS SCRIPT AS NEEDED

# CHECK SQUID CURRENT STATUS
systemctl status squid.service
if ! systemctl status squid.service; then
    echo -e "Squid service needs to be running to continue! Starting Squid now!\\n"
    sleep 2
    service squid start
    if ! service squid start; then exit 1; fi
else
    echo
    read -t 10 -p 'Sleeping 10 seconds. Press enter to continue.'
    clear
fi

# SET DEFAULT USER/OWNER OF SQUID (THE UBUNTU AND DEBIAN DEFAULT IS PROXY)
SQUID_USER='proxy'

####################
## CACHE SETTINGS ##
####################

# SET CACHE DIRECTORY PATH
CACHE_DIR_SQUID='/var/spool/squid'
# CACHE DIR SQUID SIZE UNITS IN MB
CACHE_DIR_SQUID_SIZE='800000'
CACHE_SWP_HIGH='95'
CACHE_SWP_LOW='90'
# MEMORY CACHE MODE options [ always | disk ]
MEM_CACHE_MODE='always'
# CACHE MEMORY TRANSIT FILE ALLOCATION MAX SIZE LIMIT (CAN BE INCREASED)
CACHE_MEM='1258 MB'

# LIMIT CLIENT REQUESTS BUFFER SIZE
CLIENT_RQST_BFR_SIZE='512 KB'

# FAVOR IPV6 OVER IPV4
# THIS GREATLY INCREASE OR DECREASE THE SPEED OF YOUR PROXY. IF ONE SETTINGS
# ISN'T SHOWING PROMISE TRY THE OPPOSITE AS SQUID CLAIMS TO PREFER IPV6 OVER
# IPV4 BUT MY EXPERIENCE HAS BEEN THE EXACT OPPOSITE.
DNS_V4_FIRST='on'

# FIREWALLD PROGRAM PORTS
PORT_PIHOLE='4711/tcp'
PORT_SQUID='3128/tcp'

# FIREWALLD SSH PORTS
SSH_JMACBOOK='26500/tcp'
SSH_PIHOLE='24500/tcp'
SSH_QNAS='25500/tcp'

# FIREWALLD SERVICES (THIS SHOULD BE CONSIDERED AT HOME SETTINGS WHERE YOU TRUST THE COMPUTERS ACCESSABLE TO YOUR NETWORK)
SVC01='dhcp'
SVC02='dhcpv6'
SVC03='dns'
SVC04='http'
SVC05='ssh'

# SQUID BASIC AUTHORIZATION LIBRARIES
LIB1_SQUID='/usr/lib/squid3/basic_ncsa_auth'
LIB2_SQUID='/usr/lib/squid/basic_ncsa_auth'

# THIS PC'S LAN (LOCAL) IP ADDRESS
SERVER_IP='192.168.1.40'

# OBJECT SIZES
MIN_OBJ_SIZE='0 KB'
MAX_OBJ_SIZE='10 GB'
MAX_OBJ_SIZE_MEM='1024 KB'

# SQUID FILES
SQUID_CONF='/etc/squid/squid.conf'
SQUID_PASSWD='/etc/squid/passwd'
SQUID_WHITELIST='/etc/squid/sites.whitelist'
SQUID_BLACKLIST='/etc/squid/sites.blacklist'

# DETECT BROKEN PCON SETTINGS
DETECT_BROKEN_PCONN='off'

# find which path exists
if [ -f "${LIB1_SQUID}" ]; then BASIC_NCSA_AUTH="${LIB1_SQUID}"
elif [ -f "${LIB2_SQUID}" ]; then BASIC_NCSA_AUTH="${LIB2_SQUID}"
else
    clear
    echo -e "File error: 'basic_ncsa_auth' was not found. Unable to set the required variable BASIC_NCSA_AUTH\\nPlease Fix...\\n"
    read -p 'Press enter to exit.'
    exit 1
fi

# CREATE SQUID.CONF FILE
cat > "${SQUID_CONF}" <<EOF && echo -e "squid.conf was created successfully!" || echo -e "squid.conf failed to create!"
#    WELCOME TO SQUID 5.2
#    ----------------------------
#
#    This is the documentation for the Squid configuration file.
#    This documentation can also be found online at:
#        http://www.squid-cache.org/Doc/config/
#
#    You may wish to look at the Squid home page and wiki for the
#    FAQ and other documentation:
#        http://www.squid-cache.org/
#        http://wiki.squid-cache.org/SquidFaq
#        http://wiki.squid-cache.org/ConfigExamples
#
#    This documentation shows what the defaults for various directives
#    happen to be.  If you don't need to change the default, you should
#    leave the line out of your squid.conf in most cases.
#
#    In some cases "none" refers to no default setting at all,
#    while in other cases it refers to the value of the option
#    - the comments for that keyword indicate if this is the case.
#

#  Configuration options can be included using the "include" directive.
#  Include takes a list of files to include. Quoting and wildcards are
#  supported.
#
#  For example,
#
#  include /path/to/included/file/squid.acl.config
#
#  Includes can be nested up to a hard-coded depth of 16 levels.
#  This arbitrary restriction is to prevent recursive include references
#  from causing Squid entering an infinite loop whilst trying to load
#  configuration files.
#
#  Values with byte units
#
#    Squid accepts size units on some size related directives. All
#    such directives are documented with a default value displaying
#    a unit.
#
#    Units accepted by Squid are:
#        bytes - byte
#        KB - Kilobyte (1024 bytes)
#        MB - Megabyte
#        GB - Gigabyte
#
#  Values with time units
#
#    Time-related directives marked with either "time-units" or
#    "time-units-small" accept a time unit. The supported time units are:
#
#        nanosecond (time-units-small only)
#        microsecond (time-units-small only)
#        millisecond
#        second
#        minute
#        hour
#        day
#        week
#        fortnight
#        month - 30 days
#        year - 31557790080 milliseconds (just over 365 days)
#        decade
#
#  Values with spaces, quotes, and other special characters
#
#    Squid supports directive parameters with spaces, quotes, and other
#    special characters. Surround such parameters with "double quotes". Use
#    the configuration_includes_quoted_values directive to enable or
#    disable that support.
#
#    Squid supports reading configuration option parameters from external
#    files using the syntax:
#        parameters("/path/filename")
#    For example:
#        acl allowlist dstdomain parameters("/etc/squid/allowlist.txt")
#
#  Conditional configuration
#
#    If-statements can be used to make configuration directives
#    depend on conditions:
#
#        if <CONDITION>
#            ... regular configuration directives ...
#        [else
#            ... regular configuration directives ...]
#        endif
#
#    The else part is optional. The keywords "if", "else", and "endif"
#    must be typed on their own lines, as if they were regular
#    configuration directives.
#
#    NOTE: An else-if condition is not supported.
#
#    These individual conditions types are supported:
#
#        true
#        Always evaluates to true.
#        false
#        Always evaluates to false.
#        <integer> = <integer>
#            Equality comparison of two integer numbers.
#
#
#  SMP-Related Macros
#
#    The following SMP-related preprocessor macros can be used.
#
#    ${process_name} expands to the current Squid process "name"
#    (e.g., squid1, squid2, or cache1).
#
#    ${process_number} expands to the current Squid process
#    identifier, which is an integer number (e.g., 1, 2, 3) unique
#    across all Squid processes of the current service instance.
#
#    ${service_name} expands into the current Squid service instance
#    name identifier which is provided by -n on the command line.
#
#  Logformat Macros
#
#    Logformat macros can be used in many places outside of the logformat
#    directive. In theory, all of the logformat codes can be used as %macros,
#    where they are supported. In practice, a %macro expands as a dash (-) when
#    the transaction does not yet have enough information and a value is needed.
#
#    There is no definitive list of what tokens are available at the various
#    stages of the transaction.
#
#    And some information may already be available to Squid but not yet
#    committed where the macro expansion code can access it (report
#    such instances!). The macro will be expanded into a single dash
#    ('-') in such cases. Not all macros have been tested.
#

#  TAG: broken_vary_encoding
#    This option is not yet supported by Squid-3.
#Default:
# none

#  TAG: cache_vary
#    This option is not yet supported by Squid-3.
#Default:
# none

#  TAG: error_map
#    This option is not yet supported by Squid-3.
#Default:
# none

#  TAG: external_refresh_check
#    This option is not yet supported by Squid-3.
#Default:
# none

#  TAG: location_rewrite_program
#    This option is not yet supported by Squid-3.
#Default:
# none

#  TAG: refresh_stale_hit
#    This option is not yet supported by Squid-3.
#Default:
# none

#  TAG: dns_v4_first
#    Remove this line. Squid no longer supports preferential treatment of DNS A records.
#Default:
dns_v4_first ${DNS_V4_FIRST}

#  TAG: cache_peer_domain
#    Replace with dstdomain ACLs and cache_peer_access.
#Default:
# none

#  TAG: ie_refresh
#    Remove this line. The behaviour enabled by this is no longer needed.
#Default:
# none

#  TAG: sslproxy_cafile
#    Remove this line. Use tls_outgoing_options cafile= instead.
#Default:
# none

#  TAG: sslproxy_capath
#    Remove this line. Use tls_outgoing_options capath= instead.
#Default:
# none

#  TAG: sslproxy_cipher
#    Remove this line. Use tls_outgoing_options cipher= instead.
#Default:
# none

#  TAG: sslproxy_client_certificate
#    Remove this line. Use tls_outgoing_options cert= instead.
#Default:
# none

#  TAG: sslproxy_client_key
#    Remove this line. Use tls_outgoing_options key= instead.
#Default:
# none

#  TAG: sslproxy_flags
#    Remove this line. Use tls_outgoing_options flags= instead.
#Default:
# none

#  TAG: sslproxy_options
#    Remove this line. Use tls_outgoing_options options= instead.
#Default:
# none

#  TAG: sslproxy_version
#    Remove this line. Use tls_outgoing_options options= instead.
#Default:
# none

#  TAG: hierarchy_stoplist
#    Remove this line. Use always_direct or cache_peer_access ACLs instead if you need to prevent cache_peer use.
#Default:
# none

#  TAG: log_access
#    Remove this line. Use acls with access_log directives to control access logging
#Default:
# none

#  TAG: log_icap
#    Remove this line. Use acls with icap_log directives to control icap logging
#Default:
# none

#  TAG: ignore_ims_on_miss
#    Remove this line. The HTTP/1.1 feature is now configured by 'cache_miss_revalidate'.
#Default:
# none

#  TAG: balance_on_multiple_ip
#    Remove this line. Squid performs a 'Happy Eyeballs' algorithm, this multiple-IP algorithm is not longer relevant.
#Default:
# none

#  TAG: chunked_request_body_max_size
#    Remove this line. Squid is now HTTP/1.1 compliant.
#Default:
# none

#  TAG: dns_v4_fallback
#    Remove this line. Squid performs a 'Happy Eyeballs' algorithm, the 'fallback' algorithm is no longer relevant.
#Default:
# none

#  TAG: emulate_httpd_log
#    Replace this with an access_log directive using the format 'common' or 'combined'.
#Default:
# none

#  TAG: forward_log
#    Use a regular access.log with ACL limiting it to MISS events.
#Default:
# none

#  TAG: ftp_list_width
#    Remove this line. Configure FTP page display using the CSS controls in errorpages.css instead.
#Default:
# none

#  TAG: ignore_expect_100
#    Remove this line. The HTTP/1.1 feature is now fully supported by default.
#Default:
# none

#  TAG: log_fqdn
#    Remove this option from your config. To log FQDN use %>A in the log format.
#Default:
# log_fqdn on (dpreciated/unusable)

#  TAG: log_ip_on_direct
#    Remove this option from your config. To log server or peer names use %<A in the log format.
#Default:
# none

#  TAG: maximum_single_addr_tries
#    Replaced by connect_retries. The behaviour has changed, please read the documentation before altering.
#Default:
# none

#  TAG: referer_log
#    Replace this with an access_log directive using the format 'referrer'.
#Default:
# none

#  TAG: update_headers
#    Remove this line. The feature is supported by default in storage types where update is implemented.
#Default:
# none

#  TAG: url_rewrite_concurrency
#    Remove this line. Set the 'concurrency=' option of url_rewrite_children instead.
#Default:
# none

#  TAG: useragent_log
#    Replace this with an access_log directive using the format 'useragent'.
#Default:
# none

#  TAG: dns_testnames
#    Remove this line. DNS is no longer tested on startup.
#Default:
# none

#  TAG: extension_methods
#    Remove this line. All valid methods for HTTP are accepted by default.
#Default:
# none

#  TAG: zero_buffers
#Default:
# none

#  TAG: incoming_rate
#Default:
# none

#  TAG: server_http11
#    Remove this line. HTTP/1.1 is supported by default.
#Default:
# none

#  TAG: upgrade_http0.9
#    Remove this line. ICY/1.0 streaming protocol is supported by default.
#Default:
# none

#  TAG: zph_local
#    Alter these entries. Use the qos_flows directive instead.
#Default:
# none

#  TAG: header_access
#    Since squid-3.0 replace with request_header_access or reply_header_access
#    depending on whether you wish to match client requests or server replies.
#Default:
# none

#  TAG: httpd_accel_no_pmtu_disc
#    Since squid-3.0 use the 'disable-pmtu-discovery' flag on http_port instead.
#Default:
# none

#  TAG: wais_relay_host
#    Replace this line with 'cache_peer' configuration.
#Default:
# none

#  TAG: wais_relay_port
#    Replace this line with 'cache_peer' configuration.
#Default:
# none

# OPTIONS FOR SMP
# -----------------------------------------------------------------------------

#  TAG: workers
#    Number of main Squid processes or "workers" to fork and maintain.
#    0: "no daemon" mode, like running "squid -N ..."
#    1: "no SMP" mode, start one main Squid process daemon (default)
#    N: start N main Squid process daemons (i.e., SMP mode)
#
#    In SMP mode, each worker does nearly all what a single Squid daemon
#    does (e.g., listen on http_port and forward HTTP requests).
#Default:
# SMP support disabled.

#  TAG: cpu_affinity_map
#    Usage: cpu_affinity_map process_numbers=P1,P2,... cores=C1,C2,...
#
#    Sets 1:1 mapping between Squid processes and CPU cores. For example,
#
#        cpu_affinity_map process_numbers=1,2,3,4 cores=1,3,5,7
#
#    affects processes 1 through 4 only and places them on the first
#    four even cores, starting with core #1.
#
#    CPU cores are numbered starting from 1. Requires support for
#    sched_getaffinity(2) and sched_setaffinity(2) system calls.
#
#    Multiple cpu_affinity_map options are merged.
#
#    See also: workers
#Default:
# Let operating system decide.

#  TAG: shared_memory_locking    on|off
#    Whether to ensure that all required shared memory is available by
#    "locking" that shared memory into RAM when Squid starts. The
#    alternative is faster startup time followed by slightly slower
#    performance and, if not enough RAM is actually available during
#    runtime, mysterious crashes.
#
#    SMP Squid uses many shared memory segments. These segments are
#    brought into Squid memory space using an mmap(2) system call. During
#    Squid startup, the mmap() call often succeeds regardless of whether
#    the system has enough RAM. In general, Squid cannot tell whether the
#    kernel applies this "optimistic" memory allocation policy (but
#    popular modern kernels usually use it).
#
#    Later, if Squid attempts to actually access the mapped memory
#    regions beyond what the kernel is willing to allocate, the
#    "optimistic" kernel simply kills Squid kid with a SIGBUS signal.
#    Some of the memory limits enforced by the kernel are currently
#    poorly understood: We do not know how to detect and check them. This
#    option ensures that the mapped memory will be available.
#
#    This option may have a positive performance side-effect: Locking
#    memory at start avoids runtime paging I/O. Paging slows Squid down.
#
#    Locking memory may require a large enough RLIMIT_MEMLOCK OS limit,
#    CAP_IPC_LOCK capability, or equivalent.
#Default:
# shared_memory_locking off

#  TAG: hopeless_kid_revival_delay    time-units
#    Normally, when a kid process dies, Squid immediately restarts the
#    kid. A kid experiencing frequent deaths is marked as "hopeless" for
#    the duration specified by this directive. Hopeless kids are not
#    automatically restarted.
#
#    Currently, zero values are not supported because they result in
#    misconfigured SMP Squid instances running forever, endlessly
#    restarting each dying kid. To effectively disable hopeless kids
#    revival, set the delay to a huge value (e.g., 1 year).
#
#    Reconfiguration also clears all hopeless kids designations, allowing
#    for manual revival of hopeless kids.
#Default:
# hopeless_kid_revival_delay 1 hour

# OPTIONS FOR AUTHENTICATION
# -----------------------------------------------------------------------------

#  TAG: auth_param
#    This is used to define parameters for the various authentication
#    schemes supported by Squid.
#
#        format: auth_param scheme parameter [setting]
#
#    The order in which authentication schemes are presented to the client is
#    dependent on the order the scheme first appears in config file. IE
#    has a bug (it's not RFC 2617 compliant) in that it will use the basic
#    scheme if basic is the first entry presented, even if more secure
#    schemes are presented. For now use the order in the recommended
#    settings section below. If other browsers have difficulties (don't
#    recognize the schemes offered even if you are using basic) either
#    put basic first, or disable the other schemes (by commenting out their
#    program entry).
#
#    Once an authentication scheme is fully configured, it can only be
#    shutdown by shutting squid down and restarting. Changes can be made on
#    the fly and activated with a reconfigure. I.E. You can change to a
#    different helper, but not unconfigure the helper completely.
#
#    Please note that while this directive defines how Squid processes
#    authentication it does not automatically activate authentication.
#    To use authentication you must in addition make use of ACLs based
#    on login name in http_access (proxy_auth, proxy_auth_regex or
#    external with %LOGIN used in the format tag). The browser will be
#    challenged for authentication on the first such acl encountered
#    in http_access processing and will also be re-challenged for new
#    login credentials if the request is being denied by a proxy_auth
#    type acl.
#
#    WARNING: authentication can't be used in a transparently intercepting
#    proxy as the client then thinks it is talking to an origin server and
#    not the proxy. This is a limitation of bending the TCP/IP protocol to
#    transparently intercepting port 80, not a limitation in Squid.
#    Ports flagged 'transparent', 'intercept', or 'tproxy' have
#    authentication disabled.
#
#    === Parameters common to all schemes. ===
#
#    "program" cmdline
#        Specifies the command for the external authenticator.
#
#        By default, each authentication scheme is not used unless a
#        program is specified.
#
#        See http://wiki.squid-cache.org/Features/AddonHelpers for
#        more details on helper operations and creating your own.
#
#    "key_extras" format
#        Specifies a string to be append to request line format for
#        the authentication helper. "Quoted" format values may contain
#        spaces and logformat %macros. In theory, any logformat %macro
#        can be used. In practice, a %macro expands as a dash (-) if
#        the helper request is sent before the required macro
#        information is available to Squid.
#
#        By default, Squid uses request formats provided in
#        scheme-specific examples below (search for %credentials).
#
#        The expanded key_extras value is added to the Squid credentials
#        cache and, hence, will affect authentication. It can be used to
#        autenticate different users with identical user names (e.g.,
#        when user authentication depends on http_port).
#
#        Avoid adding frequently changing information to key_extras. For
#        example, if you add user source IP, and it changes frequently
#        in your environment, then max_user_ip ACL is going to treat
#        every user+IP combination as a unique "user", breaking the ACL
#        and wasting a lot of memory on those user records. It will also
#        force users to authenticate from scratch whenever their IP
#        changes.
#
#    "realm" string
#        Specifies the protection scope (aka realm name) which is to be
#        reported to the client for the authentication scheme. It is
#        commonly part of the text the user will see when prompted for
#        their username and password.
#
#        For Basic the default is "Squid proxy-caching web server".
#        For Digest there is no default, this parameter is mandatory.
#        For NTLM and Negotiate this parameter is ignored.
#
#    "children" numberofchildren [startup=N] [idle=N] [concurrency=N]
#        [queue-size=N] [on-persistent-overload=action]
#        [reservation-timeout=seconds]
#
#        The maximum number of authenticator processes to spawn. If
#        you start too few Squid will have to wait for them to process
#        a backlog of credential verifications, slowing it down. When
#        password verifications are done via a (slow) network you are
#        likely to need lots of authenticator processes.
#
#        The startup= and idle= options permit some skew in the exact
#        amount run. A minimum of startup=N will begin during startup
#        and reconfigure. Squid will start more in groups of up to
#        idle=N in an attempt to meet traffic needs and to keep idle=N
#        free above those traffic needs up to the maximum.
#
#        The concurrency= option sets the number of concurrent requests
#        the helper can process.  The default of 0 is used for helpers
#        who only supports one request at a time. Setting this to a
#        number greater than 0 changes the protocol used to include a
#        channel ID field first on the request/response line, allowing
#        multiple requests to be sent to the same helper in parallel
#        without waiting for the response.
#
#        Concurrency must not be set unless it's known the helper
#        supports the input format with channel-ID fields.
#
#        The queue-size option sets the maximum number of queued
#        requests. A request is queued when no existing child can
#        accept it due to concurrency limit and no new child can be
#        started due to numberofchildren limit. The default maximum is
#        2*numberofchildren. Squid is allowed to temporarily exceed the
#        configured maximum, marking the affected helper as
#        "overloaded". If the helper overload lasts more than 3
#        minutes, the action prescribed by the on-persistent-overload
#        option applies.
#
#        The on-persistent-overload=action option specifies Squid
#        reaction to a new helper request arriving when the helper
#        has been overloaded for more that 3 minutes already. The number
#        of queued requests determines whether the helper is overloaded
#        (see the queue-size option).
#
#        Two actions are supported:
#
#          die    Squid worker quits. This is the default behavior.
#
#          ERR    Squid treats the helper request as if it was
#            immediately submitted, and the helper immediately
#            replied with an ERR response. This action has no effect
#            on the already queued and in-progress helper requests.
#
#        NOTE: NTLM and Negotiate schemes do not support concurrency
#            in the Squid code module even though some helpers can.
#
#        The reservation-timeout=seconds option allows NTLM and Negotiate
#        helpers to forget about clients that abandon their in-progress
#        connection authentication without closing the connection. The
#        timeout is measured since the last helper response received by
#        Squid for the client. Fractional seconds are not supported.
#
#        After the timeout, the helper will be used for other clients if
#        there are no unreserved helpers available. In the latter case,
#        the old client attempt to resume authentication will not be
#        forwarded to the helper (and the client should open a new HTTP
#        connection and retry authentication from scratch).
#
#        By default, reservations do not expire and clients that keep
#        their connections open without completing authentication may
#        exhaust all NTLM and Negotiate helpers.
#
#    "keep_alive" on|off
#        If you experience problems with PUT/POST requests when using
#        the NTLM or Negotiate schemes then you can try setting this
#        to off. This will cause Squid to forcibly close the connection
#        on the initial request where the browser asks which schemes
#        are supported by the proxy.
#
#        For Basic and Digest this parameter is ignored.
#
#    "utf8" on|off
#        Useful for sending credentials to authentication backends that
#        expect UTF-8 encoding (e.g., LDAP).
#
#        When this option is enabled, Squid uses HTTP Accept-Language
#        request header to guess the received credentials encoding
#        (ISO-Latin-1, CP1251, or UTF-8) and then converts the first
#        two encodings into UTF-8.
#
#        When this option is disabled and by default, Squid sends
#        credentials in their original (i.e. received) encoding.
#
#        This parameter is only honored for Basic and Digest schemes.
#        For Basic, the entire username:password credentials are
#        checked and, if necessary, re-encoded. For Digest -- just the
#        username component. For NTLM and Negotiate schemes, this
#        parameter is ignored.
#
#
#    === Example Configuration ===
#
#    This configuration displays the recommended authentication scheme
#    order from most to least secure with recommended minimum configuration
#    settings for each scheme:
#
##auth_param negotiate program <uncomment and complete this line to activate>
##auth_param negotiate children 20 startup=0 idle=1
##
##auth_param digest program <uncomment and complete this line to activate>
##auth_param digest children 20 startup=0 idle=1
##auth_param digest realm Squid proxy-caching web server
##auth_param digest nonce_garbage_interval 5 minutes
##auth_param digest nonce_max_duration 30 minutes
##auth_param digest nonce_max_count 50
##
##auth_param ntlm program <uncomment and complete this line to activate>
##auth_param ntlm children 20 startup=0 idle=1
##
##auth_param basic program <uncomment and complete this line>
##auth_param basic children 5 startup=5 idle=1
##auth_param basic credentialsttl 2 hours
#Default:
# none

#  TAG: authenticate_cache_garbage_interval
#    The time period between garbage collection across the username cache.
#    This is a trade-off between memory utilization (long intervals - say
#    2 days) and CPU (short intervals - say 1 minute). Only change if you
#    have good reason to.
#Default:
# authenticate_cache_garbage_interval 1 hour

#  TAG: authenticate_ttl
#    The time a user & their credentials stay in the logged in
#    user cache since their last request. When the garbage
#    interval passes, all user credentials that have passed their
#    TTL are removed from memory.
#Default:
# authenticate_ttl 1 hour

#  TAG: authenticate_ip_ttl
#    If you use proxy authentication and the 'max_user_ip' ACL,
#    this directive controls how long Squid remembers the IP
#    addresses associated with each user.  Use a small value
#    (e.g., 60 seconds) if your users might change addresses
#    quickly, as is the case with dialup.   You might be safe
#    using a larger value (e.g., 2 hours) in a corporate LAN
#    environment with relatively static address assignments.
#Default:
# authenticate_ip_ttl 1 second

# ACCESS CONTROLS
# -----------------------------------------------------------------------------

#  TAG: external_acl_type
#    This option defines external acl classes using a helper program
#    to look up the status
#
#      external_acl_type name [options] FORMAT /path/to/helper [helper arguments]
#
#    Options:
#
#      ttl=n        TTL in seconds for cached results (defaults to 3600
#            for 1 hour)
#
#      negative_ttl=n
#            TTL for cached negative lookups (default same
#            as ttl)
#
#      grace=n    Percentage remaining of TTL where a refresh of a
#            cached entry should be initiated without needing to
#            wait for a new reply. (default is for no grace period)
#
#      cache=n    The maximum number of entries in the result cache. The
#            default limit is 262144 entries.  Each cache entry usually
#            consumes at least 256 bytes. Squid currently does not remove
#            expired cache entries until the limit is reached, so a proxy
#            will sooner or later reach the limit. The expanded FORMAT
#            value is used as the cache key, so if the details in FORMAT
#            are highly variable, a larger cache may be needed to produce
#            reduction in helper load.
#
#      children-max=n
#            Maximum number of acl helper processes spawned to service
#            external acl lookups of this type. (default 5)
#
#      children-startup=n
#            Minimum number of acl helper processes to spawn during
#            startup and reconfigure to service external acl lookups
#            of this type. (default 0)
#
#      children-idle=n
#            Number of acl helper processes to keep ahead of traffic
#            loads. Squid will spawn this many at once whenever load
#            rises above the capabilities of existing processes.
#            Up to the value of children-max. (default 1)
#
#      concurrency=n    concurrency level per process. Only used with helpers
#            capable of processing more than one query at a time.
#
#      queue-size=N  The queue-size option sets the maximum number of
#            queued requests. A request is queued when no existing
#            helper can accept it due to concurrency limit and no
#            new helper can be started due to children-max limit.
#            If the queued requests exceed queue size, the acl is
#            ignored. The default value is set to 2*children-max.
#
#      protocol=2.5    Compatibility mode for Squid-2.5 external acl helpers.
#
#      ipv4 / ipv6    IP protocol used to communicate with this helper.
#            The default is to auto-detect IPv6 and use it when available.
#
#
#    FORMAT is a series of %macro codes. See logformat directive for a full list
#    of the accepted codes. Although note that at the time of any external ACL
#    being tested data may not be available and thus some %macro expand to '-'.
#
#    In addition to the logformat codes; when processing external ACLs these
#    additional macros are made available:
#
#      %ACL        The name of the ACL being tested.
#
#      %DATA        The ACL arguments specified in the referencing config
#            'acl ... external' line, separated by spaces (an
#            "argument string"). see acl external.
#
#            If there are no ACL arguments %DATA expands to '-'.
#
#            If you do not specify a DATA macro inside FORMAT,
#            Squid automatically appends %DATA to your FORMAT.
#            Note that Squid-3.x may expand %DATA to whitespace
#            or nothing in this case.
#
#            By default, Squid applies URL-encoding to each ACL
#            argument inside the argument string. If an explicit
#            encoding modifier is used (e.g., %#DATA), then Squid
#            encodes the whole argument string as a single token
#            (e.g., with %#DATA, spaces between arguments become
#            %20).
#
#    If SSL is enabled, the following formating codes become available:
#
#      %USER_CERT        SSL User certificate in PEM format
#      %USER_CERTCHAIN    SSL User certificate chain in PEM format
#      %USER_CERT_xx        SSL User certificate subject attribute xx
#      %USER_CA_CERT_xx    SSL User certificate issuer attribute xx
#
#
#    NOTE: all other format codes accepted by older Squid versions
#        are deprecated.
#
#
#    General request syntax:
#
#      [channel-ID] FORMAT-values
#
#
#    FORMAT-values consists of transaction details expanded with
#    whitespace separation per the config file FORMAT specification
#    using the FORMAT macros listed above.
#
#    Request values sent to the helper are URL escaped to protect
#    each value in requests against whitespaces.
#
#    If using protocol=2.5 then the request sent to the helper is not
#    URL escaped to protect against whitespace.
#
#    NOTE: protocol=3.0 is deprecated as no longer necessary.
#
#    When using the concurrency= option the protocol is changed by
#    introducing a query channel tag in front of the request/response.
#    The query channel tag is a number between 0 and concurrency-1.
#    This value must be echoed back unchanged to Squid as the first part
#    of the response relating to its request.
#
#
#    The helper receives lines expanded per the above format specification
#    and for each input line returns 1 line starting with OK/ERR/BH result
#    code and optionally followed by additional keywords with more details.
#
#
#    General result syntax:
#
#      [channel-ID] result keyword=value ...
#
#    Result consists of one of the codes:
#
#      OK
#        the ACL test produced a match.
#
#      ERR
#        the ACL test does not produce a match.
#
#      BH
#        An internal error occurred in the helper, preventing
#        a result being identified.
#
#    The meaning of 'a match' is determined by your squid.conf
#    access control configuration. See the Squid wiki for details.
#
#    Defined keywords:
#
#      user=        The users name (login)
#
#      password=    The users password (for login= cache_peer option)
#
#      message=    Message describing the reason for this response.
#            Available as %o in error pages.
#            Useful on (ERR and BH results).
#
#      tag=        Apply a tag to a request. Only sets a tag once,
#            does not alter existing tags.
#
#      log=        String to be logged in access.log. Available as
#            %ea in logformat specifications.
#
#      clt_conn_tag= Associates a TAG with the client TCP connection.
#            Please see url_rewrite_program related documentation
#            for this kv-pair.
#
#    Any keywords may be sent on any response whether OK, ERR or BH.
#
#    All response keyword values need to be a single token with URL
#    escaping, or enclosed in double quotes (") and escaped using \ on
#    any double quotes or \ characters within the value. The wrapping
#    double quotes are removed before the value is interpreted by Squid.
#    \r and \n are also replace by CR and LF.
#
#    Some example key values:
#
#        user=John%20Smith
#        user="John Smith"
#        user="J. \"Bob\" Smith"
#Default:
# none

#  TAG: acl
#    Defining an Access List
#
#    Every access list definition must begin with an aclname and acltype,
#    followed by either type-specific arguments or a quoted filename that
#    they are read from.
#
#       acl aclname acltype argument ...
#       acl aclname acltype "file" ...
#
#    When using "file", the file should contain one item per line.
#
#
#    ACL Options
#
#    Some acl types supports options which changes their default behaviour:
#
#    -i,+i    By default, regular expressions are CASE-SENSITIVE. To make them
#        case-insensitive, use the -i option. To return case-sensitive
#        use the +i option between patterns, or make a new ACL line
#        without -i.
#
#    -n    Disable lookups and address type conversions.  If lookup or
#        conversion is required because the parameter type (IP or
#        domain name) does not match the message address type (domain
#        name or IP), then the ACL would immediately declare a mismatch
#        without any warnings or lookups.
#
#    -m[=delimiters]
#        Perform a list membership test, interpreting values as
#        comma-separated token lists and matching against individual
#        tokens instead of whole values.
#        The optional "delimiters" parameter specifies one or more
#        alternative non-alphanumeric delimiter characters.
#        non-alphanumeric delimiter characters.
#
#    --    Used to stop processing all options, in the case the first acl
#        value has '-' character as first character (for example the '-'
#        is a valid domain name)
#
#    Some acl types require suspending the current request in order
#    to access some external data source.
#    Those which do are marked with the tag [slow], those which
#    don't are marked as [fast].
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl
#    for further information
#
#    ***** ACL TYPES AVAILABLE *****
#
#    acl aclname src ip-address/mask ...    # clients IP address [fast]
#    acl aclname src addr1-addr2/mask ...    # range of addresses [fast]
#    acl aclname dst [-n] ip-address/mask ...    # URL host's IP address [slow]
#    acl aclname localip ip-address/mask ... # IP address the client connected to [fast]
#
#if USE_SQUID_EUI
#    acl aclname arp      mac-address ...
#    acl aclname eui64    eui64-address ...
#      # [fast]
#      # MAC (EUI-48) and EUI-64 addresses use xx:xx:xx:xx:xx:xx notation.
#      #
#      # The 'arp' ACL code is not portable to all operating systems.
#      # It works on Linux, Solaris, Windows, FreeBSD, and some other
#      # BSD variants.
#      #
#      # The eui_lookup directive is required to be 'on' (the default)
#      # and Squid built with --enable-eui for MAC/EUI addresses to be
#      # available for this ACL.
#      #
#      # Squid can only determine the MAC/EUI address for IPv4
#      # clients that are on the same subnet. If the client is on a
#      # different subnet, then Squid cannot find out its address.
#      #
#      # IPv6 protocol does not contain ARP. MAC/EUI is either
#      # encoded directly in the IPv6 address or not available.
#endif
#    acl aclname clientside_mark mark[/mask] ...
#      # matches CONNMARK of an accepted connection [fast]
#      # DEPRECATED. Use the 'client_connection_mark' instead.
#
#    acl aclname client_connection_mark mark[/mask] ...
#      # matches CONNMARK of an accepted connection [fast]
#      #
#      # mark and mask are unsigned integers (hex, octal, or decimal).
#      # If multiple marks are given, then the ACL matches if at least
#      # one mark matches.
#      #
#      # Uses netfilter-conntrack library.
#      # Requires building Squid with --enable-linux-netfilter.
#      #
#      # The client, various intermediaries, and Squid itself may set
#      # CONNMARK at various times. The last CONNMARK set wins. This ACL
#      # checks the mark present on an accepted connection or set by
#      # Squid afterwards, depending on the ACL check timing. This ACL
#      # effectively ignores any mark set by other agents after Squid has
#      # accepted the connection.
#
#    acl aclname srcdomain   .foo.com ...
#      # reverse lookup, from client IP [slow]
#    acl aclname dstdomain [-n] .foo.com ...
#      # Destination server from URL [fast]
#    acl aclname srcdom_regex [-i] \.foo\.com ...
#      # regex matching client name [slow]
#    acl aclname dstdom_regex [-n] [-i] \.foo\.com ...
#      # regex matching server [fast]
#      #
#      # For dstdomain and dstdom_regex a reverse lookup is tried if a IP
#      # based URL is used and no match is found. The name "none" is used
#      # if the reverse lookup fails.
#
#    acl aclname src_as number ...
#    acl aclname dst_as number ...
#      # [fast]
#      # Except for access control, AS numbers can be used for
#      # routing of requests to specific caches. Here's an
#      # example for routing all requests for AS#1241 and only
#      # those to mycache.mydomain.net:
#      # acl asexample dst_as 1241
#      # cache_peer_access mycache.mydomain.net allow asexample
#      # cache_peer_access mycache_mydomain.net deny all
#
#    acl aclname peername myPeer ...
#    acl aclname peername_regex [-i] regex-pattern ...
#      # [fast]
#      # match against a named cache_peer entry
#      # set unique name= on cache_peer lines for reliable use.
#
#    acl aclname time [day-abbrevs] [h1:m1-h2:m2]
#      # [fast]
#      #  day-abbrevs:
#      #    S - Sunday
#      #    M - Monday
#      #    T - Tuesday
#      #    W - Wednesday
#      #    H - Thursday
#      #    F - Friday
#      #    A - Saturday
#      #  h1:m1 must be less than h2:m2
#
#    acl aclname url_regex [-i] ^http:// ...
#      # regex matching on whole URL [fast]
#    acl aclname urllogin [-i] [^a-zA-Z0-9] ...
#      # regex matching on URL login field
#    acl aclname urlpath_regex [-i] \.gif$ ...
#      # regex matching on URL path [fast]
#
#    acl aclname port 80 70 21 0-1024...   # destination TCP port [fast]
#                                          # ranges are alloed
#    acl aclname localport 3128 ...          # TCP port the client connected to [fast]
#                                          # NP: for interception mode this is usually '80'
#
#    acl aclname myportname 3128 ...       # *_port name [fast]
#
#    acl aclname proto HTTP FTP ...        # request protocol [fast]
#
#    acl aclname method GET POST ...       # HTTP request method [fast]
#
#    acl aclname http_status 200 301 500- 400-403 ...
#      # status code in reply [fast]
#
#    acl aclname browser [-i] regexp ...
#      # pattern match on User-Agent header (see also req_header below) [fast]
#
#    acl aclname referer_regex [-i] regexp ...
#      # pattern match on Referer header [fast]
#      # Referer is highly unreliable, so use with care
#
#    acl aclname ident [-i] username ...
#    acl aclname ident_regex [-i] pattern ...
#      # string match on ident output [slow]
#      # use REQUIRED to accept any non-null ident.
#
#    acl aclname proxy_auth [-i] username ...
#    acl aclname proxy_auth_regex [-i] pattern ...
#      # perform http authentication challenge to the client and match against
#      # supplied credentials [slow]
#      #
#      # takes a list of allowed usernames.
#      # use REQUIRED to accept any valid username.
#      #
#      # Will use proxy authentication in forward-proxy scenarios, and plain
#      # http authenticaiton in reverse-proxy scenarios
#      #
#      # NOTE: when a Proxy-Authentication header is sent but it is not
#      # needed during ACL checking the username is NOT logged
#      # in access.log.
#      #
#      # NOTE: proxy_auth requires a EXTERNAL authentication program
#      # to check username/password combinations (see
#      # auth_param directive).
#      #
#      # NOTE: proxy_auth can't be used in a transparent/intercepting proxy
#      # as the browser needs to be configured for using a proxy in order
#      # to respond to proxy authentication.
#
#    acl aclname snmp_community string ...
#      # A community string to limit access to your SNMP Agent [fast]
#      # Example:
#      #
#      #    acl snmppublic snmp_community public
#
#    acl aclname maxconn number
#      # This will be matched when the client's IP address has
#      # more than <number> TCP connections established. [fast]
#      # NOTE: This only measures direct TCP links so X-Forwarded-For
#      # indirect clients are not counted.
#
#    acl aclname max_user_ip [-s] number
#      # This will be matched when the user attempts to log in from more
#      # than <number> different ip addresses. The authenticate_ip_ttl
#      # parameter controls the timeout on the ip entries. [fast]
#      # If -s is specified the limit is strict, denying browsing
#      # from any further IP addresses until the ttl has expired. Without
#      # -s Squid will just annoy the user by "randomly" denying requests.
#      # (the counter is reset each time the limit is reached and a
#      # request is denied)
#      # NOTE: in acceleration mode or where there is mesh of child proxies,
#      # clients may appear to come from multiple addresses if they are
#      # going through proxy farms, so a limit of 1 may cause user problems.
#
#    acl aclname random probability
#      # Pseudo-randomly match requests. Based on the probability given.
#      # Probability may be written as a decimal (0.333), fraction (1/3)
#      # or ratio of matches:non-matches (3:5).
#
#    acl aclname req_mime_type [-i] mime-type ...
#      # regex match against the mime type of the request generated
#      # by the client. Can be used to detect file upload or some
#      # types HTTP tunneling requests [fast]
#      # NOTE: This does NOT match the reply. You cannot use this
#      # to match the returned file type.
#
#    acl aclname req_header header-name [-i] any\.regex\.here
#      # regex match against any of the known request headers.  May be
#      # thought of as a superset of "browser", "referer" and "mime-type"
#      # ACL [fast]
#
#    acl aclname rep_mime_type [-i] mime-type ...
#      # regex match against the mime type of the reply received by
#      # squid. Can be used to detect file download or some
#      # types HTTP tunneling requests. [fast]
#      # NOTE: This has no effect in http_access rules. It only has
#      # effect in rules that affect the reply data stream such as
#      # http_reply_access.
#
#    acl aclname rep_header header-name [-i] any\.regex\.here
#      # regex match against any of the known reply headers. May be
#      # thought of as a superset of "browser", "referer" and "mime-type"
#      # ACLs [fast]
#
#    acl aclname external class_name [arguments...]
#      # external ACL lookup via a helper class defined by the
#      # external_acl_type directive [slow]
#
#    acl aclname user_cert attribute values...
#      # match against attributes in a user SSL certificate
#      # attribute is one of DN/C/O/CN/L/ST or a numerical OID [fast]
#
#    acl aclname ca_cert attribute values...
#      # match against attributes a users issuing CA SSL certificate
#      # attribute is one of DN/C/O/CN/L/ST or a numerical OID  [fast]
#
#    acl aclname ext_user [-i] username ...
#    acl aclname ext_user_regex [-i] pattern ...
#      # string match on username returned by external acl helper [slow]
#      # use REQUIRED to accept any non-null user name.
#
#    acl aclname tag tagvalue ...
#      # string match on tag returned by external acl helper [fast]
#      # DEPRECATED. Only the first tag will match with this ACL.
#      # Use the 'note' ACL instead for handling multiple tag values.
#
#    acl aclname hier_code codename ...
#      # string match against squid hierarchy code(s); [fast]
#      #  e.g., DIRECT, PARENT_HIT, NONE, etc.
#      #
#      # NOTE: This has no effect in http_access rules. It only has
#      # effect in rules that affect the reply data stream such as
#      # http_reply_access.
#
#    acl aclname note [-m[=delimiters]] name [value ...]
#      # match transaction annotation [fast]
#      # Without values, matches any annotation with a given name.
#      # With value(s), matches any annotation with a given name that
#      # also has one of the given values.
#      # If the -m flag is used, then the value of the named
#      # annotation is interpreted as a list of tokens, and the ACL
#      # matches individual name=token pairs rather than whole
#      # name=value pairs. See "ACL Options" above for more info.
#      # Annotation sources include note and adaptation_meta directives
#      # as well as helper and eCAP responses.
#
#    acl aclname annotate_transaction [-m[=delimiters]] key=value ...
#    acl aclname annotate_transaction [-m[=delimiters]] key+=value ...
#      # Always matches. [fast]
#      # Used for its side effect: This ACL immediately adds a
#      # key=value annotation to the current master transaction.
#      # The added annotation can then be tested using note ACL and
#      # logged (or sent to helpers) using %note format code.
#      #
#      # Annotations can be specified using replacement and addition
#      # formats. The key=value form replaces old same-key annotation
#      # value(s). The key+=value form appends a new value to the old
#      # same-key annotation. Both forms create a new key=value
#      # annotation if no same-key annotation exists already. If
#      # -m flag is used, then the value is interpreted as a list
#      # and the annotation will contain key=token pair(s) instead of the
#      # whole key=value pair.
#      #
#      # This ACL is especially useful for recording complex multi-step
#      # ACL-driven decisions. For example, the following configuration
#      # avoids logging transactions accepted after aclX matched:
#      #
#      #  # First, mark transactions accepted after aclX matched
#      #  acl markSpecial annotate_transaction special=true
#      #  http_access allow acl001
#      #  ...
#      #  http_access deny acl100
#      #  http_access allow aclX markSpecial
#      #
#      #  # Second, do not log marked transactions:
#      #  acl markedSpecial note special true
#      #  access_log ... deny markedSpecial
#      #
#      #  # Note that the following would not have worked because aclX
#      #  # alone does not determine whether the transaction was allowed:
#      #  access_log ... deny aclX # Wrong!
#      #
#      # Warning: This ACL annotates the transaction even when negated
#      # and even if subsequent ACLs fail to match. For example, the
#      # following three rules will have exactly the same effect as far
#      # as annotations set by the "mark" ACL are concerned:
#      #
#      #  some_directive acl1 ... mark # rule matches if mark is reached
#      #  some_directive acl1 ... !mark     # rule never matches
#      #  some_directive acl1 ... mark !all # rule never matches
#
#    acl aclname annotate_client [-m[=delimiters]] key=value ...
#    acl aclname annotate_client [-m[=delimiters]] key+=value ...
#      #
#      # Always matches. [fast]
#      # Used for its side effect: This ACL immediately adds a
#      # key=value annotation to the current client-to-Squid
#      # connection. Connection annotations are propagated to the current
#      # and all future master transactions on the annotated connection.
#      # See the annotate_transaction ACL for details.
#      #
#      # For example, the following configuration avoids rewriting URLs
#      # of transactions bumped by SslBump:
#      #
#      #  # First, mark bumped connections:
#      #  acl markBumped annotate_client bumped=true
#      #  ssl_bump peek acl1
#      #  ssl_bump stare acl2
#      #  ssl_bump bump acl3 markBumped
#      #  ssl_bump splice all
#      #
#      #  # Second, do not send marked transactions to the redirector:
#      #  acl markedBumped note bumped true
#      #  url_rewrite_access deny markedBumped
#      #
#      #  # Note that the following would not have worked because acl3 alone
#      #  # does not determine whether the connection is going to be bumped:
#      #  url_rewrite_access deny acl3 # Wrong!
#
#    acl aclname adaptation_service service ...
#      # Matches the name of any icap_service, ecap_service,
#      # adaptation_service_set, or adaptation_service_chain that Squid
#      # has used (or attempted to use) for the master transaction.
#      # This ACL must be defined after the corresponding adaptation
#      # service is named in squid.conf. This ACL is usable with
#      # adaptation_meta because it starts matching immediately after
#      # the service has been selected for adaptation.
#
#    acl aclname transaction_initiator initiator ...
#      # Matches transaction's initiator [fast]
#      #
#      # Supported initiators are:
#      #  esi: matches transactions fetching ESI resources
#      #  certificate-fetching: matches transactions fetching
#      #     a missing intermediate TLS certificate
#      #  cache-digest: matches transactions fetching Cache Digests
#      #     from a cache_peer
#      #  htcp: matches HTCP requests from peers
#      #  icp: matches ICP requests to peers
#      #  icmp: matches ICMP RTT database (NetDB) requests to peers
#      #  asn: matches asns db requests
#      #  internal: matches any of the above
#      #  client: matches transactions containing an HTTP or FTP
#      #     client request received at a Squid *_port
#      #  all: matches any transaction, including internal transactions
#      #     without a configurable initiator and hopefully rare
#      #     transactions without a known-to-Squid initiator
#      #
#      # Multiple initiators are ORed.
#
#    acl aclname has component
#      # matches a transaction "component" [fast]
#      #
#      # Supported transaction components are:
#      #  request: transaction has a request header (at least)
#      #  response: transaction has a response header (at least)
#      #  ALE: transaction has an internally-generated Access Log Entry
#      #       structure; bugs notwithstanding, all transaction have it
#      #
#      # For example, the following configuration helps when dealing with HTTP
#      # clients that close connections without sending a request header:
#      #
#      #  acl hasRequest has request
#      #  acl logMe note important_transaction
#      #  # avoid "logMe ACL is used in context without an HTTP request" warnings
#      #  access_log ... logformat=detailed hasRequest logMe
#      #  # log request-less transactions, instead of ignoring them
#      #  access_log ... logformat=brief !hasRequest
#      #
#      # Multiple components are not supported for one "acl" rule, but
#      # can be specified (and are ORed) using multiple same-name rules:
#      #
#      #  # OK, this strange logging daemon needs request or response,
#      #  # but can work without either a request or a response:
#      #  acl hasWhatMyLoggingDaemonNeeds has request
#      #  acl hasWhatMyLoggingDaemonNeeds has response
#
#acl aclname at_step step
#      # match against the current request processing step [fast]
#      # Valid steps are:
#      #   GeneratingCONNECT: Generating HTTP CONNECT request headers
#
#    acl aclname any-of acl1 acl2 ...
#      # match any one of the acls [fast or slow]
#      # The first matching ACL stops further ACL evaluation.
#      #
#      # ACLs from multiple any-of lines with the same name are ORed.
#      # For example, A = (a1 or a2) or (a3 or a4) can be written as
#      #   acl A any-of a1 a2
#      #   acl A any-of a3 a4
#      #
#      # This group ACL is fast if all evaluated ACLs in the group are fast
#      # and slow otherwise.
#
#    acl aclname all-of acl1 acl2 ...
#      # match all of the acls [fast or slow]
#      # The first mismatching ACL stops further ACL evaluation.
#      #
#      # ACLs from multiple all-of lines with the same name are ORed.
#      # For example, B = (b1 and b2) or (b3 and b4) can be written as
#      #   acl B all-of b1 b2
#      #   acl B all-of b3 b4
#      #
#      # This group ACL is fast if all evaluated ACLs in the group are fast
#      # and slow otherwise.
#
#    Examples:
#        acl macaddress arp 09:00:2b:23:45:67
#        acl myexample dst_as 1241
#        acl password proxy_auth REQUIRED
#        acl fileupload req_mime_type -i ^multipart/form-data$
#        acl javascript rep_mime_type -i ^application/x-javascript$
#
#Default:
# ACLs all, manager, localhost, to_localhost, and CONNECT are predefined.
#
#
# Recommended minimum configuration:
#

# Example rule allowing access from your local networks.
# Adapt to list your (internal) IP networks from where browsing should be allowed.
acl localnet src 0.0.0.1-0.255.255.255          # RFC 1122 "this" network [LAN]
acl localnet src 10.0.0.0/8                     # RFC 1918 local private network [LAN]
acl localnet src 100.64.0.0/10                  # RFC 6598 shared address space [CGN]
acl localnet src 169.254.0.0/16                 # RFC 3927 link-local [directly plugged] machines
acl localnet src 172.16.0.0/12                  # RFC 1918 local private network [LAN]
acl localnet src 192.168.0.0/16                 # RFC 1918 local private network [LAN]
acl localnet src fc00::/7                       # RFC 4193 local private network range
acl localnet src fe80::/10                      # RFC 4291 link-local [directly plugged] machines

acl SSL_ports port 443
acl Safe_ports port 80                          # http
acl Safe_ports port 21                          # ftp
acl Safe_ports port 443                         # https
acl Safe_ports port 70                          # gopher
acl Safe_ports port 210                         # wais
acl Safe_ports port 1025-65535                  # unregistered ports
acl Safe_ports port 280                         # http-mgmt
acl Safe_ports port 488                         # gss-http
acl Safe_ports port 591                         # filemaker
acl Safe_ports port 777                         # multiling http
acl Safe_ports port 20000                       # pihole gui
acl Safe_ports port 24500                       # ssh ubuntu-jammy
acl Safe_ports port 25500                       # ssh qnas
acl Safe_ports port 26500                       # ssh jmacbook
acl whitelist dstdomain "${SQUID_WHITELIST}"    # site whitelist file
acl blocked_sites dstdomain ${SQUID_BLACKLIST}  # site blacklist file

#  TAG: proxy_protocol_access
#    Determine which client proxies can be trusted to provide correct
#    information regarding real client IP address using PROXY protocol.
#
#    Requests may pass through a chain of several other proxies
#    before reaching us. The original source details may by sent in:
#        * HTTP message Forwarded header, or
#        * HTTP message X-Forwarded-For header, or
#        * PROXY protocol connection header.
#
#    This directive is solely for validating new PROXY protocol
#    connections received from a port flagged with require-proxy-header.
#    It is checked only once after TCP connection setup.
#
#    A deny match results in TCP connection closure.
#
#    An allow match is required for Squid to permit the corresponding
#    TCP connection, before Squid even looks for HTTP request headers.
#    If there is an allow match, Squid starts using PROXY header information
#    to determine the source address of the connection for all future ACL
#    checks, logging, etc.
#
#    SECURITY CONSIDERATIONS:
#
#        Any host from which we accept client IP details can place
#        incorrect information in the relevant header, and Squid
#        will use the incorrect information as if it were the
#        source address of the request.  This may enable remote
#        hosts to bypass any access control restrictions that are
#        based on the client's source addresses.
#
#    This clause only supports fast acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#Default:
# all TCP connections to ports with require-proxy-header will be denied

#  TAG: follow_x_forwarded_for
#    Determine which client proxies can be trusted to provide correct
#    information regarding real client IP address.
#
#    Requests may pass through a chain of several other proxies
#    before reaching us. The original source details may by sent in:
#        * HTTP message Forwarded header, or
#        * HTTP message X-Forwarded-For header, or
#        * PROXY protocol connection header.
#
#    PROXY protocol connections are controlled by the proxy_protocol_access
#    directive which is checked before this.
#
#    If a request reaches us from a source that is allowed by this
#    directive, then we trust the information it provides regarding
#    the IP of the client it received from (if any).
#
#    For the purpose of ACLs used in this directive the src ACL type always
#    matches the address we are testing and srcdomain matches its rDNS.
#
#    On each HTTP request Squid checks for X-Forwarded-For header fields.
#    If found the header values are iterated in reverse order and an allow
#    match is required for Squid to continue on to the next value.
#    The verification ends when a value receives a deny match, cannot be
#    tested, or there are no more values to test.
#    NOTE: Squid does not yet follow the Forwarded HTTP header.
#
#    The end result of this process is an IP address that we will
#    refer to as the indirect client address.  This address may
#    be treated as the client address for access control, ICAP, delay
#    pools and logging, depending on the acl_uses_indirect_client,
#    icap_uses_indirect_client, delay_pool_uses_indirect_client,
#    log_uses_indirect_client and tproxy_uses_indirect_client options.
#
#    This clause only supports fast acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#
#    SECURITY CONSIDERATIONS:
#
#        Any host from which we accept client IP details can place
#        incorrect information in the relevant header, and Squid
#        will use the incorrect information as if it were the
#        source address of the request.  This may enable remote
#        hosts to bypass any access control restrictions that are
#        based on the client's source addresses.
#
#    For example:
#
#        acl localhost src 127.0.0.1
#        acl my_other_proxy srcdomain .proxy.example.com
#        follow_x_forwarded_for allow localhost
#        follow_x_forwarded_for allow my_other_proxy
#Default:
# X-Forwarded-For header will be ignored.

#  TAG: acl_uses_indirect_client    on|off
#    Controls whether the indirect client address
#    (see follow_x_forwarded_for) is used instead of the
#    direct client address in acl matching.
#
#    NOTE: maxconn ACL considers direct TCP links and indirect
#          clients will always have zero. So no match.
#Default:
# acl_uses_indirect_client on

#  TAG: delay_pool_uses_indirect_client    on|off
#    Controls whether the indirect client address
#    (see follow_x_forwarded_for) is used instead of the
#    direct client address in delay pools.
#Default:
# delay_pool_uses_indirect_client on

#  TAG: log_uses_indirect_client    on|off
#    Controls whether the indirect client address
#    (see follow_x_forwarded_for) is used instead of the
#    direct client address in the access log.
#Default:
# log_uses_indirect_client on

#  TAG: tproxy_uses_indirect_client    on|off
#    Controls whether the indirect client address
#    (see follow_x_forwarded_for) is used instead of the
#    direct client address when spoofing the outgoing client.
#
#    This has no effect on requests arriving in non-tproxy
#    mode ports.
#
#    SECURITY WARNING: Usage of this option is dangerous
#    and should not be used trivially. Correct configuration
#    of follow_x_forwarded_for with a limited set of trusted
#    sources is required to prevent abuse of your proxy.
#Default:
# tproxy_uses_indirect_client off

#  TAG: spoof_client_ip
#    Control client IP address spoofing of TPROXY traffic based on
#    defined access lists.
#
#    spoof_client_ip allow|deny [!]aclname ...
#
#    If there are no "spoof_client_ip" lines present, the default
#    is to "allow" spoofing of any suitable request.
#
#    Note that the cache_peer "no-tproxy" option overrides this ACL.
#
#    This clause supports fast acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#Default:
# Allow spoofing on all TPROXY traffic.

#  TAG: http_access
#    Allowing or Denying access based on defined access lists
#
#    To allow or deny a message received on an HTTP, HTTPS, or FTP port:
#    http_access allow|deny [!]aclname ...
#
#    NOTE on default values:
#
#    If there are no "access" lines present, the default is to deny
#    the request.
#
#    If none of the "access" lines cause a match, the default is the
#    opposite of the last line in the list.  If the last line was
#    deny, the default is allow.  Conversely, if the last line
#    is allow, the default will be deny.  For these reasons, it is a
#    good idea to have an "deny all" entry at the end of your access
#    lists to avoid potential confusion.
#
#    This clause supports both fast and slow acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#
#Default:
# Deny, unless rules exist in squid.conf.
#

#
# Recommended minimum Access Permission configuration:
#
# Deny requests to certain unsafe ports
http_access allow !Safe_ports

# Allow CONNECT to other than secure SSL ports
http_access allow !SSL_ports

# Only allow cachemgr access from localhost
http_access allow localhost manager
http_access deny manager

# We strongly recommend the following be uncommented to protect innocent
# web applications running on the proxy server who think the only
# one who can access services on "localhost" is a local user
http_access deny to_localhost

#
# INSERT YOUR OWN RULE(S) HERE TO ALLOW ACCESS FROM YOUR CLIENTS
#
include /etc/squid/conf.d/*

#
##############################
## START OF CUSTOM COMMANDS ##
##############################
#

auth_param basic program ${BASIC_NCSA_AUTH} ${SQUID_PASSWD}
auth_param basic children 5
auth_param basic realm proxy
acl authenticated proxy_auth REQUIRED
acl auth_users proxy_auth REQUIRED

# Adapt localnet in the ACL section to list your (internal) IP networks from where browsing should be allowed
http_access allow localnet
http_access allow localhost
http_access allow authenticated
http_access allow whitelist
http_access deny blocked_sites

# And finally deny all other access to this proxy
http_access deny all

#
# This specifies the maximum buffer size of a client request.
# It prevents squid eating too much memory when somebody uploads a large file.
#
client_request_buffer_max_size ${CLIENT_RQST_BFR_SIZE}

# set dns nameserver addresses
dns_nameservers ${SERVER_IP}

# Set the file size range the proxy will actively cache
minimum_object_size ${MIN_OBJ_SIZE}
maximum_object_size ${MAX_OBJ_SIZE}
maximum_object_size_in_memory ${MAX_OBJ_SIZE_MEM}

cache_swap_low ${CACHE_SWP_LOW}
cache_swap_high ${CACHE_SWP_HIGH}

# always: Keep most recently fetched objects in memory (default)
memory_cache_mode ${MEM_CACHE_MODE}

# Uncomment and adjust the following to add a disk cache directory.
cache_dir ufs ${CACHE_DIR_SQUID} ${CACHE_DIR_SQUID_SIZE} 16 256

#
########################################
## Your custom refresh_patterns below ##
########################################
#
refresh_pattern \/master$                                    0         0%        0  refresh-ims
#
####################################
## default refresh_patterns below ##
####################################
#
refresh_pattern ^ftp:                                     1440        20%    10080
refresh_pattern ^gopher:                                  1440         0%     1440
refresh_pattern -i (/cgi-bin/|\?)                            0         0%        0
refresh_pattern \/(Packages|Sources)(|\.bz2|\.gz|\.xz)$      0         0%        0  refresh-ims
refresh_pattern \/Release(|\.gpg)$                           0         0%        0  refresh-ims
refresh_pattern \/InRelease$                                 0         0%        0  refresh-ims
refresh_pattern \/(Translation-.*)(|\.bz2|\.gz|\.xz)$        0         0%        0  refresh-ims
# example pattern for deb packages
refresh_pattern (\.deb|\.udeb)$                         129600       100%   129600
refresh_pattern .                                            0        20%     4320
#

# Cache memory transit file allocation max size limit
cache_mem ${CACHE_MEM}

# set default squid proxy port
http_port ${PORT_SQUID::4}

# set visible hostname
visible_hostname debian-bullseye

# Some servers incorrectly signal the use of HTTP/1.0 persistent connections including on replies
# not compatible, causing significant delays. Mostly happens on redirects. Enabling attempts to
# detect broken replies and automatically assumes the reply is finished after a 10 second timeout.
detect_broken_pconn ${DETECT_BROKEN_PCONN}

# SET DEFAULT USER/OWNER FOR SQUID
cache_effective_user ${SQUID_USER}

http_accel_surrogate_remote on
esi_parser expat

#
############################
## END OF CUSTOM COMMANDS ##
############################
#

#  TAG: adapted_http_access
#    Allowing or Denying access based on defined access lists
#
#    Essentially identical to http_access, but runs after redirectors
#    and ICAP/eCAP adaptation. Allowing access control based on their
#    output.
#
#    If not set then only http_access is used.
#Default:
# Allow, unless rules exist in squid.conf.

#  TAG: http_reply_access
#    Allow replies to client requests. This is complementary to http_access.
#
#    http_reply_access allow|deny [!] aclname ...
#
#    NOTE: if there are no access lines present, the default is to allow
#    all replies.
#
#    If none of the access lines cause a match the opposite of the
#    last line will apply. Thus it is good practice to end the rules
#    with an "allow all" or "deny all" entry.
#
#    This clause supports both fast and slow acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#Default:
# Allow, unless rules exist in squid.conf.

#  TAG: icp_access
#    Allowing or Denying access to the ICP port based on defined
#    access lists
#
#    icp_access  allow|deny [!]aclname ...
#
#    NOTE: The default if no icp_access lines are present is to
#    deny all traffic. This default may cause problems with peers
#    using ICP.
#
#    This clause only supports fast acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#
## Allow ICP queries from local networks only
##icp_access allow localnet
##icp_access deny all
#Default:
# Deny, unless rules exist in squid.conf.

#  TAG: htcp_access
#    Allowing or Denying access to the HTCP port based on defined
#    access lists
#
#    htcp_access  allow|deny [!]aclname ...
#
#    See also htcp_clr_access for details on access control for
#    cache purge (CLR) HTCP messages.
#
#    NOTE: The default if no htcp_access lines are present is to
#    deny all traffic. This default may cause problems with peers
#    using the htcp option.
#
#    This clause only supports fast acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#
## Allow HTCP queries from local networks only
##htcp_access allow localnet
##htcp_access deny all
#Default:
# Deny, unless rules exist in squid.conf.

#  TAG: htcp_clr_access
#    Allowing or Denying access to purge content using HTCP based
#    on defined access lists.
#    See htcp_access for details on general HTCP access control.
#
#    htcp_clr_access  allow|deny [!]aclname ...
#
#    This clause only supports fast acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#
## Allow HTCP CLR requests from trusted peers
#acl htcp_clr_peer src 192.0.2.2 2001:DB8::2
#htcp_clr_access allow htcp_clr_peer
#htcp_clr_access deny all
#Default:
# Deny, unless rules exist in squid.conf.

#  TAG: miss_access
#    Determines whether network access is permitted when satisfying a request.
#
#    For example;
#        to force your neighbors to use you as a sibling instead of
#        a parent.
#
#        acl localclients src 192.0.2.0/24 2001:DB8::a:0/64
#        miss_access deny  !localclients
#        miss_access allow all
#
#    This means only your local clients are allowed to fetch relayed/MISS
#    replies from the network and all other clients can only fetch cached
#    objects (HITs).
#
#    The default for this setting allows all clients who passed the
#    http_access rules to relay via this proxy.
#
#    This clause only supports fast acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#Default:
# Allow, unless rules exist in squid.conf.

#  TAG: ident_lookup_access
#    A list of ACL elements which, if matched, cause an ident
#    (RFC 931) lookup to be performed for this request.  For
#    example, you might choose to always perform ident lookups
#    for your main multi-user Unix boxes, but not for your Macs
#    and PCs.  By default, ident lookups are not performed for
#    any requests.
#
#    To enable ident lookups for specific client addresses, you
#    can follow this example:
#
#    acl ident_aware_hosts src 198.168.1.0/24
#    ident_lookup_access allow ident_aware_hosts
#    ident_lookup_access deny all
#
#    Only src type ACL checks are fully supported.  A srcdomain
#    ACL might work at times, but it will not always provide
#    the correct result.
#
#    This clause only supports fast acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#Default:
# Unless rules exist in squid.conf, IDENT is not fetched.

#  TAG: reply_body_max_size    size [acl acl...]
#    This option specifies the maximum size of a reply body. It can be
#    used to prevent users from downloading very large files, such as
#    MP3's and movies. When the reply headers are received, the
#    reply_body_max_size lines are processed, and the first line where
#    all (if any) listed ACLs are true is used as the maximum body size
#    for this reply.
#
#    This size is checked twice. First when we get the reply headers,
#    we check the content-length value.  If the content length value exists
#    and is larger than the allowed size, the request is denied and the
#    user receives an error message that says "the request or reply
#    is too large." If there is no content-length, and the reply
#    size exceeds this limit, the client's connection is just closed
#    and they will receive a partial reply.
#
#    WARNING: downstream caches probably can not detect a partial reply
#    if there is no content-length header, so they will cache
#    partial responses and give them out as hits.  You should NOT
#    use this option if you have downstream caches.
#
#    WARNING: A maximum size smaller than the size of squid's error messages
#    will cause an infinite loop and crash squid. Ensure that the smallest
#    non-zero value you use is greater that the maximum header size plus
#    the size of your largest error page.
#
#    If you set this parameter none (the default), there will be
#    no limit imposed.
#
#    Configuration Format is:
#        reply_body_max_size SIZE UNITS [acl ...]
#    ie.
#        reply_body_max_size 10 MB
#
#Default:
# No limit is applied.

#  TAG: on_unsupported_protocol
#    Determines Squid behavior when encountering strange requests at the
#    beginning of an accepted TCP connection or the beginning of a bumped
#    CONNECT tunnel. Controlling Squid reaction to unexpected traffic is
#    especially useful in interception environments where Squid is likely
#    to see connections for unsupported protocols that Squid should either
#    terminate or tunnel at TCP level.
#
#        on_unsupported_protocol <action> [!]acl ...
#
#    The first matching action wins. Only fast ACLs are supported.
#
#    Supported actions are:
#
#    tunnel: Establish a TCP connection with the intended server and
#        blindly shovel TCP packets between the client and server.
#
#    respond: Respond with an error message, using the transfer protocol
#        for the Squid port that received the request (e.g., HTTP
#        for connections intercepted at the http_port). This is the
#        default.
#
#    Squid expects the following traffic patterns:
#
#      http_port: a plain HTTP request
#      https_port: SSL/TLS handshake followed by an [encrypted] HTTP request
#      ftp_port: a plain FTP command (no on_unsupported_protocol support yet!)
#      CONNECT tunnel on http_port: same as https_port
#      CONNECT tunnel on https_port: same as https_port
#
#    Currently, this directive has effect on intercepted connections and
#    bumped tunnels only. Other cases are not supported because Squid
#    cannot know the intended destination of other traffic.
#
#    For example:
#      # define what Squid errors indicate receiving non-HTTP traffic:
#      acl foreignProtocol squid_error ERR_PROTOCOL_UNKNOWN ERR_TOO_BIG
#      # define what Squid errors indicate receiving nothing:
#      acl serverTalksFirstProtocol squid_error ERR_REQUEST_START_TIMEOUT
#      # tunnel everything that does not look like HTTP:
#          on_unsupported_protocol tunnel foreignProtocol
#      # tunnel if we think the client waits for the server to talk first:
#      on_unsupported_protocol tunnel serverTalksFirstProtocol
#      # in all other error cases, just send an HTTP "error page" response:
#      on_unsupported_protocol respond all
#
#    See also: squid_error ACL
#Default:
# Respond with an error message to unidentifiable traffic

#  TAG: auth_schemes
#    Use this directive to customize authentication schemes presence and
#    order in Squid's Unauthorized and Authentication Required responses.
#
#        auth_schemes scheme1,scheme2,... [!]aclname ...
#
#    where schemeN is the name of one of the authentication schemes
#    configured using auth_param directives. At least one scheme name is
#    required. Multiple scheme names are separated by commas. Either
#    avoid whitespace or quote the entire schemes list.
#
#    A special "ALL" scheme name expands to all auth_param-configured
#    schemes in their configuration order. This directive cannot be used
#    to configure Squid to offer no authentication schemes at all.
#
#    The first matching auth_schemes rule determines the schemes order
#    for the current Authentication Required transaction. Note that the
#    future response is not yet available during auth_schemes evaluation.
#
#    If this directive is not used or none of its rules match, then Squid
#    responds with all configured authentication schemes in the order of
#    auth_param directives in the configuration file.
#
#    This directive does not determine when authentication is used or
#    how each authentication scheme authenticates clients.
#
#    The following example sends basic and negotiate authentication
#    schemes, in that order, when requesting authentication of HTTP
#    requests matching the isIE ACL (not shown) while sending all
#    auth_param schemes in their configuration order to other clients:
#
#        auth_schemes basic,negotiate isIE
#        auth_schemes ALL all # explicit default
#
#    This directive supports fast ACLs only.
#
#    See also: auth_param.
#Default:
# use all auth_param schemes in their configuration order

# NETWORK OPTIONS
# -----------------------------------------------------------------------------

#  TAG: http_port
#    Usage:    port [mode] [options]
#        hostname:port [mode] [options]
#        1.2.3.4:port [mode] [options]
#
#    The socket addresses where Squid will listen for HTTP client
#    requests.  You may specify multiple socket addresses.
#    There are three forms: port alone, hostname with port, and
#    IP address with port.  If you specify a hostname or IP
#    address, Squid binds the socket to that specific
#    address. Most likely, you do not need to bind to a specific
#    address, so you can use the port number alone.
#
#    If you are running Squid in accelerator mode, you
#    probably want to listen on port 80 also, or instead.
#
#    The -a command line option may be used to specify additional
#    port(s) where Squid listens for proxy request. Such ports will
#    be plain proxy ports with no options.
#
#    You may specify multiple socket addresses on multiple lines.
#
#    Modes:
#
#       intercept    Support for IP-Layer NAT interception delivering
#            traffic to this Squid port.
#            NP: disables authentication on the port.
#
#       tproxy    Support Linux TPROXY (or BSD divert-to) with spoofing
#            of outgoing connections using the client IP address.
#            NP: disables authentication on the port.
#
#       accel    Accelerator / reverse proxy mode
#
#       ssl-bump    For each CONNECT request allowed by ssl_bump ACLs,
#            establish secure connection with the client and with
#            the server, decrypt HTTPS messages as they pass through
#            Squid, and treat them as unencrypted HTTP messages,
#            becoming the man-in-the-middle.
#
#            The ssl_bump option is required to fully enable
#            bumping of CONNECT requests.
#
#    Omitting the mode flag causes default forward proxy mode to be used.
#
#
#    Accelerator Mode Options:
#
#       defaultsite=domainname
#            What to use for the Host: header if it is not present
#            in a request. Determines what site (not origin server)
#            accelerators should consider the default.
#
#       no-vhost    Disable using HTTP/1.1 Host header for virtual domain support.
#
#       protocol=    Protocol to reconstruct accelerated and intercepted
#            requests with. Defaults to HTTP/1.1 for http_port and
#            HTTPS/1.1 for https_port.
#            When an unsupported value is configured Squid will
#            produce a FATAL error.
#            Values: HTTP or HTTP/1.1, HTTPS or HTTPS/1.1
#
#       vport    Virtual host port support. Using the http_port number
#            instead of the port passed on Host: headers.
#
#       vport=NN    Virtual host port support. Using the specified port
#            number instead of the port passed on Host: headers.
#
#       act-as-origin
#            Act as if this Squid is the origin server.
#            This currently means generate new Date: and Expires:
#            headers on HIT instead of adding Age:.
#
#       ignore-cc    Ignore request Cache-Control headers.
#
#            WARNING: This option violates HTTP specifications if
#            used in non-accelerator setups.
#
#       allow-direct    Allow direct forwarding in accelerator mode. Normally
#            accelerated requests are denied direct forwarding as if
#            never_direct was used.
#
#            WARNING: this option opens accelerator mode to security
#            vulnerabilities usually only affecting in interception
#            mode. Make sure to protect forwarding with suitable
#            http_access rules when using this.
#
#
#    SSL Bump Mode Options:
#        In addition to these options ssl-bump requires TLS/SSL options.
#
#       generate-host-certificates[=<on|off>]
#            Dynamically create SSL server certificates for the
#            destination hosts of bumped CONNECT requests.When
#            enabled, the cert and key options are used to sign
#            generated certificates. Otherwise generated
#            certificate will be selfsigned.
#            If there is a CA certificate lifetime of the generated
#            certificate equals lifetime of the CA certificate. If
#            generated certificate is selfsigned lifetime is three
#            years.
#            This option is enabled by default when ssl-bump is used.
#            See the ssl-bump option above for more information.
#
#       dynamic_cert_mem_cache_size=SIZE
#            Approximate total RAM size spent on cached generated
#            certificates. If set to zero, caching is disabled. The
#            default value is 4MB.
#
#    TLS / SSL Options:
#
#       tls-cert=    Path to file containing an X.509 certificate (PEM format)
#            to be used in the TLS handshake ServerHello.
#
#            If this certificate is constrained by KeyUsage TLS
#            feature it must allow HTTP server usage, along with
#            any additional restrictions imposed by your choice
#            of options= settings.
#
#            When OpenSSL is used this file may also contain a
#            chain of intermediate CA certificates to send in the
#            TLS handshake.
#
#            When GnuTLS is used this option (and any paired
#            tls-key= option) may be repeated to load multiple
#            certificates for different domains.
#
#            Also, when generate-host-certificates=on is configured
#            the first tls-cert= option must be a CA certificate
#            capable of signing the automatically generated
#            certificates.
#
#       tls-key=    Path to a file containing private key file (PEM format)
#            for the previous tls-cert= option.
#
#            If tls-key= is not specified tls-cert= is assumed to
#            reference a PEM file containing both the certificate
#            and private key.
#
#       cipher=    Colon separated list of supported ciphers.
#            NOTE: some ciphers such as EDH ciphers depend on
#                  additional settings. If those settings are
#                  omitted the ciphers may be silently ignored
#                  by the OpenSSL library.
#
#       options=    Various SSL implementation options. The most important
#            being:
#
#                NO_SSLv3    Disallow the use of SSLv3
#
#                NO_TLSv1    Disallow the use of TLSv1.0
#
#                NO_TLSv1_1  Disallow the use of TLSv1.1
#
#                NO_TLSv1_2  Disallow the use of TLSv1.2
#
#                SINGLE_DH_USE
#                      Always create a new key when using
#                      temporary/ephemeral DH key exchanges
#
#                SINGLE_ECDH_USE
#                      Enable ephemeral ECDH key exchange.
#                      The adopted curve should be specified
#                      using the tls-dh option.
#
#                NO_TICKET
#                      Disable use of RFC5077 session tickets.
#                      Some servers may have problems
#                      understanding the TLS extension due
#                      to ambiguous specification in RFC4507.
#
#                ALL       Enable various bug workarounds
#                      suggested as "harmless" by OpenSSL
#                      Be warned that this reduces SSL/TLS
#                      strength to some attacks.
#
#            See the OpenSSL SSL_CTX_set_options documentation for a
#            more complete list.
#
#       clientca=    File containing the list of CAs to use when
#            requesting a client certificate.
#
#       tls-cafile=    PEM file containing CA certificates to use when verifying
#            client certificates. If not configured clientca will be
#            used. May be repeated to load multiple files.
#
#       capath=    Directory containing additional CA certificates
#            and CRL lists to use when verifying client certificates.
#            Requires OpenSSL or LibreSSL.
#
#       crlfile=    File of additional CRL lists to use when verifying
#            the client certificate, in addition to CRLs stored in
#            the capath. Implies VERIFY_CRL flag below.
#
#       tls-dh=[curve:]file
#            File containing DH parameters for temporary/ephemeral DH key
#            exchanges, optionally prefixed by a curve for ephemeral ECDH
#            key exchanges.
#            See OpenSSL documentation for details on how to create the
#            DH parameter file. Supported curves for ECDH can be listed
#            using the "openssl ecparam -list_curves" command.
#            WARNING: EDH and EECDH ciphers will be silently disabled if
#                 this option is not set.
#
#       sslflags=    Various flags modifying the use of SSL:
#                DELAYED_AUTH
#                Don't request client certificates
#                immediately, but wait until acl processing
#                requires a certificate (not yet implemented).
#                CONDITIONAL_AUTH
#                Request a client certificate during the TLS
#                handshake, but ignore certificate absence in
#                the TLS client Hello. If the client does
#                supply a certificate, it is validated.
#                NO_SESSION_REUSE
#                Don't allow for session reuse. Each connection
#                will result in a new SSL session.
#                VERIFY_CRL
#                Verify CRL lists when accepting client
#                certificates.
#                VERIFY_CRL_ALL
#                Verify CRL lists for all certificates in the
#                client certificate chain.
#
#       tls-default-ca[=off]
#            Whether to use the system Trusted CAs. Default is OFF.
#
#       tls-no-npn    Do not use the TLS NPN extension to advertise HTTP/1.1.
#
#       sslcontext=    SSL session ID context identifier.
#
#    Other Options:
#
#       connection-auth[=on|off]
#                    use connection-auth=off to tell Squid to prevent
#                    forwarding Microsoft connection oriented authentication
#            (NTLM, Negotiate and Kerberos)
#
#       disable-pmtu-discovery=
#            Control Path-MTU discovery usage:
#                off        lets OS decide on what to do (default).
#                transparent    disable PMTU discovery when transparent
#                    support is enabled.
#                always    disable always PMTU discovery.
#
#            In many setups of transparently intercepting proxies
#            Path-MTU discovery can not work on traffic towards the
#            clients. This is the case when the intercepting device
#            does not fully track connections and fails to forward
#            ICMP must fragment messages to the cache server. If you
#            have such setup and experience that certain clients
#            sporadically hang or never complete requests set
#            disable-pmtu-discovery option to 'transparent'.
#
#       name=    Specifies a internal name for the port. Defaults to
#            the port specification (port or addr:port)
#
#       tcpkeepalive[=idle,interval,timeout]
#            Enable TCP keepalive probes of idle connections.
#            In seconds; idle is the initial time before TCP starts
#            probing the connection, interval how often to probe, and
#            timeout the time before giving up.
#
#       require-proxy-header
#            Require PROXY protocol version 1 or 2 connections.
#            The proxy_protocol_access is required to permit
#            downstream proxies which can be trusted.
#
#       worker-queues
#            Ask TCP stack to maintain a dedicated listening queue
#            for each worker accepting requests at this port.
#            Requires TCP stack that supports the SO_REUSEPORT socket
#            option.
#
#            SECURITY WARNING: Enabling worker-specific queues
#            allows any process running as Squid's effective user to
#            easily accept requests destined to this port.
#
#    If you run Squid on a dual-homed machine with an internal
#    and an external interface we recommend you to specify the
#    internal address:port in http_port. This way Squid will only be
#    visible on the internal address.
#
#

# Squid normally listens to port 3128
#

#  TAG: https_port
#    Usage:  [ip:]port [mode] tls-cert=certificate.pem [options]
#
#    The socket address where Squid will listen for client requests made
#    over TLS or SSL connections. Commonly referred to as HTTPS.
#
#    This is most useful for situations where you are running squid in
#    accelerator mode and you want to do the TLS work at the accelerator
#    level.
#
#    You may specify multiple socket addresses on multiple lines,
#    each with their own certificate and/or options.
#
#    The tls-cert= option is mandatory on HTTPS ports.
#
#    See http_port for a list of modes and options.
#Default:
# none

#  TAG: ftp_port
#    Enables Native FTP proxy by specifying the socket address where Squid
#    listens for FTP client requests. See http_port directive for various
#    ways to specify the listening address and mode.
#
#    Usage: ftp_port address [mode] [options]
#
#    WARNING: This is a new, experimental, complex feature that has seen
#    limited production exposure. Some Squid modules (e.g., caching) do not
#    currently work with native FTP proxying, and many features have not
#    even been tested for compatibility. Test well before deploying!
#
#    Native FTP proxying differs substantially from proxying HTTP requests
#    with ftp:// URIs because Squid works as an FTP server and receives
#    actual FTP commands (rather than HTTP requests with FTP URLs).
#
#    Native FTP commands accepted at ftp_port are internally converted or
#    wrapped into HTTP-like messages. The same happens to Native FTP
#    responses received from FTP origin servers. Those HTTP-like messages
#    are shoveled through regular access control and adaptation layers
#    between the FTP client and the FTP origin server. This allows Squid to
#    examine, adapt, block, and log FTP exchanges. Squid reuses most HTTP
#    mechanisms when shoveling wrapped FTP messages. For example,
#    http_access and adaptation_access directives are used.
#
#    Modes:
#
#       intercept    Same as http_port intercept. The FTP origin address is
#            determined based on the intended destination of the
#            intercepted connection.
#
#       tproxy    Support Linux TPROXY for spoofing outgoing
#            connections using the client IP address.
#            NP: disables authentication and maybe IPv6 on the port.
#
#    By default (i.e., without an explicit mode option), Squid extracts the
#    FTP origin address from the login@origin parameter of the FTP USER
#    command. Many popular FTP clients support such native FTP proxying.
#
#    Options:
#
#       name=token    Specifies an internal name for the port. Defaults to
#            the port address. Usable with myportname ACL.
#
#       ftp-track-dirs
#            Enables tracking of FTP directories by injecting extra
#            PWD commands and adjusting Request-URI (in wrapping
#            HTTP requests) to reflect the current FTP server
#            directory. Tracking is disabled by default.
#
#       protocol=FTP    Protocol to reconstruct accelerated and intercepted
#            requests with. Defaults to FTP. No other accepted
#            values have been tested with. An unsupported value
#            results in a FATAL error. Accepted values are FTP,
#            HTTP (or HTTP/1.1), and HTTPS (or HTTPS/1.1).
#
#    Other http_port modes and options that are not specific to HTTP and
#    HTTPS may also work.
#Default:
# none

#  TAG: tcp_outgoing_tos
#    Allows you to select a TOS/Diffserv value for packets outgoing
#    on the server side, based on an ACL.
#
#    tcp_outgoing_tos ds-field [!]aclname ...
#
#    Example where normal_service_net uses the TOS value 0x00
#    and good_service_net uses 0x20
#
#    acl normal_service_net src 10.0.0.0/24
#    acl good_service_net src 10.0.1.0/24
#    tcp_outgoing_tos 0x00 normal_service_net
#    tcp_outgoing_tos 0x20 good_service_net
#
#    TOS/DSCP values really only have local significance - so you should
#    know what you're specifying. For more information, see RFC2474,
#    RFC2475, and RFC3260.
#
#    The TOS/DSCP byte must be exactly that - a octet value  0 - 255, or
#    "default" to use whatever default your host has.
#    Note that only multiples of 4 are usable as the two rightmost bits have
#    been redefined for use by ECN (RFC 3168 section 23.1).
#    The squid parser will enforce this by masking away the ECN bits.
#
#    Processing proceeds in the order specified, and stops at first fully
#    matching line.
#
#    Only fast ACLs are supported.
#Default:
# none

#  TAG: clientside_tos
#    Allows you to select a TOS/DSCP value for packets being transmitted
#    on the client-side, based on an ACL.
#
#    clientside_tos ds-field [!]aclname ...
#
#    Example where normal_service_net uses the TOS value 0x00
#    and good_service_net uses 0x20
#
#    acl normal_service_net src 10.0.0.0/24
#    acl good_service_net src 10.0.1.0/24
#    clientside_tos 0x00 normal_service_net
#    clientside_tos 0x20 good_service_net
#
#    Note: This feature is incompatible with qos_flows. Any TOS values set here
#    will be overwritten by TOS values in qos_flows.
#
#    The TOS/DSCP byte must be exactly that - a octet value  0 - 255, or
#    "default" to use whatever default your host has.
#    Note that only multiples of 4 are usable as the two rightmost bits have
#    been redefined for use by ECN (RFC 3168 section 23.1).
#    The squid parser will enforce this by masking away the ECN bits.
#
#    This clause only supports fast acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#Default:
# none

#  TAG: tcp_outgoing_mark
# Note: This option is only available if Squid is rebuilt with the
#       Packet MARK (Linux)
#
#    Allows you to apply a Netfilter mark value to outgoing packets
#    on the server side, based on an ACL.
#
#    tcp_outgoing_mark mark-value [!]aclname ...
#
#    Example where normal_service_net uses the mark value 0x00
#    and good_service_net uses 0x20
#
#    acl normal_service_net src 10.0.0.0/24
#    acl good_service_net src 10.0.1.0/24
#    tcp_outgoing_mark 0x00 normal_service_net
#    tcp_outgoing_mark 0x20 good_service_net
#
#    Only fast ACLs are supported.
#Default:
# none

#  TAG: mark_client_packet
# Note: This option is only available if Squid is rebuilt with the
#       Packet MARK (Linux)
#
#    Allows you to apply a Netfilter MARK value to packets being transmitted
#    on the client-side, based on an ACL.
#
#    mark_client_packet mark-value [!]aclname ...
#
#    Example where normal_service_net uses the MARK value 0x00
#    and good_service_net uses 0x20
#
#    acl normal_service_net src 10.0.0.0/24
#    acl good_service_net src 10.0.1.0/24
#    mark_client_packet 0x00 normal_service_net
#    mark_client_packet 0x20 good_service_net
#
#    Note: This feature is incompatible with qos_flows. Any mark values set here
#    will be overwritten by mark values in qos_flows.
#
#    This clause only supports fast acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#Default:
# none

#  TAG: mark_client_connection
# Note: This option is only available if Squid is rebuilt with the
#       Packet MARK (Linux)
#
#    Allows you to apply a Netfilter CONNMARK value to a connection
#    on the client-side, based on an ACL.
#
#    mark_client_connection mark-value[/mask] [!]aclname ...
#
#    The mark-value and mask are unsigned integers (hex, octal, or decimal).
#    The mask may be used to preserve marking previously set by other agents
#    (e.g., iptables).
#
#    A matching rule replaces the CONNMARK value. If a mask is also
#    specified, then the masked bits of the original value are zeroed, and
#    the configured mark-value is ORed with that adjusted value.
#    For example, applying a mark-value 0xAB/0xF to 0x5F CONNMARK, results
#    in a 0xFB marking (rather than a 0xAB or 0x5B).
#
#    This directive semantics is similar to iptables --set-mark rather than
#    --set-xmark functionality.
#
#    The directive does not interfere with qos_flows (which uses packet MARKs,
#    not CONNMARKs).
#
#    Example where squid marks intercepted FTP connections:
#
#    acl proto_ftp proto FTP
#    mark_client_connection 0x200/0xff00 proto_ftp
#
#    This clause only supports fast acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#Default:
# none

#  TAG: qos_flows
#    Allows you to select a TOS/DSCP value to mark outgoing
#    connections to the client, based on where the reply was sourced.
#    For platforms using netfilter, allows you to set a netfilter mark
#    value instead of, or in addition to, a TOS value.
#
#    By default this functionality is disabled. To enable it with the default
#    settings simply use "qos_flows mark" or "qos_flows tos". Default
#    settings will result in the netfilter mark or TOS value being copied
#    from the upstream connection to the client. Note that it is the connection
#    CONNMARK value not the packet MARK value that is copied.
#
#    It is not currently possible to copy the mark or TOS value from the
#    client to the upstream connection request.
#
#    TOS values really only have local significance - so you should
#    know what you're specifying. For more information, see RFC2474,
#    RFC2475, and RFC3260.
#
#    The TOS/DSCP byte must be exactly that - a octet value  0 - 255.
#    Note that only multiples of 4 are usable as the two rightmost bits have
#    been redefined for use by ECN (RFC 3168 section 23.1).
#    The squid parser will enforce this by masking away the ECN bits.
#
#    Mark values can be any unsigned 32-bit integer value.
#
#    This setting is configured by setting the following values:
#
#    tos|mark                Whether to set TOS or netfilter mark values
#
#    local-hit=0xFF        Value to mark local cache hits.
#
#    sibling-hit=0xFF    Value to mark hits from sibling peers.
#
#    parent-hit=0xFF        Value to mark hits from parent peers.
#
#    miss=0xFF[/mask]    Value to mark cache misses. Takes precedence
#                over the preserve-miss feature (see below), unless
#                mask is specified, in which case only the bits
#                specified in the mask are written.
#
#    The TOS variant of the following features are only possible on Linux
#    and require your kernel to be patched with the TOS preserving ZPH
#    patch, available from http://zph.bratcheda.org
#    No patch is needed to preserve the netfilter mark, which will work
#    with all variants of netfilter.
#
#    disable-preserve-miss
#        This option disables the preservation of the TOS or netfilter
#        mark. By default, the existing TOS or netfilter mark value of
#        the response coming from the remote server will be retained
#        and masked with miss-mark.
#        NOTE: in the case of a netfilter mark, the mark must be set on
#        the connection (using the CONNMARK target) not on the packet
#        (MARK target).
#
#    miss-mask=0xFF
#        Allows you to mask certain bits in the TOS or mark value
#        received from the remote server, before copying the value to
#        the TOS sent towards clients.
#        Default for tos: 0xFF (TOS from server is not changed).
#        Default for mark: 0xFFFFFFFF (mark from server is not changed).
#
#    All of these features require the --enable-zph-qos compilation flag
#    (enabled by default). Netfilter marking also requires the
#    libnetfilter_conntrack libraries (--with-netfilter-conntrack) and
#    libcap 2.09+ (--with-libcap).
#
#Default:
# none

#  TAG: tcp_outgoing_address
#    Allows you to map requests to different outgoing IP addresses
#    based on the username or source address of the user making
#    the request.
#
#    tcp_outgoing_address ipaddr [[!]aclname] ...
#
#    For example;
#        Forwarding clients with dedicated IPs for certain subnets.
#
#      acl normal_service_net src 10.0.0.0/24
#      acl good_service_net src 10.0.2.0/24
#
#      tcp_outgoing_address 2001:db8::c001 good_service_net
#      tcp_outgoing_address 10.1.0.2 good_service_net
#
#      tcp_outgoing_address 2001:db8::beef normal_service_net
#      tcp_outgoing_address 10.1.0.1 normal_service_net
#
#      tcp_outgoing_address 2001:db8::1
#      tcp_outgoing_address 10.1.0.3
#
#    Processing proceeds in the order specified, and stops at first fully
#    matching line.
#
#    Squid will add an implicit IP version test to each line.
#    Requests going to IPv4 websites will use the outgoing 10.1.0.* addresses.
#    Requests going to IPv6 websites will use the outgoing 2001:db8:* addresses.
#
#
#    NOTE: The use of this directive using client dependent ACLs is
#    incompatible with the use of server side persistent connections. To
#    ensure correct results it is best to set server_persistent_connections
#    to off when using this directive in such configurations.
#
#    NOTE: The use of this directive to set a local IP on outgoing TCP links
#    is incompatible with using TPROXY to set client IP out outbound TCP links.
#    When needing to contact peers use the no-tproxy cache_peer option and the
#    client_dst_passthru directive re-enable normal forwarding such as this.
#
#    This clause only supports fast acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#Default:
# Address selection is performed by the operating system.

#  TAG: host_verify_strict
#    Regardless of this option setting, when dealing with intercepted
#    traffic, Squid always verifies that the destination IP address matches
#    the Host header domain or IP (called 'authority form URL').
#
#    This enforcement is performed to satisfy a MUST-level requirement in
#    RFC 2616 section 14.23: "The Host field value MUST represent the naming
#    authority of the origin server or gateway given by the original URL".
#
#    When set to ON:
#        Squid always responds with an HTTP 409 (Conflict) error
#        page and logs a security warning if there is no match.
#
#        Squid verifies that the destination IP address matches
#        the Host header for forward-proxy and reverse-proxy traffic
#        as well. For those traffic types, Squid also enables the
#        following checks, comparing the corresponding Host header
#        and Request-URI components:
#
#         * The host names (domain or IP) must be identical,
#           but valueless or missing Host header disables all checks.
#           For the two host names to match, both must be either IP
#           or FQDN.
#
#         * Port numbers must be identical, but if a port is missing
#           the scheme-default port is assumed.
#
#
#    When set to OFF (the default):
#        Squid allows suspicious requests to continue but logs a
#        security warning and blocks caching of the response.
#
#         * Forward-proxy traffic is not checked at all.
#
#         * Reverse-proxy traffic is not checked at all.
#
#         * Intercepted traffic which passes verification is handled
#           according to client_dst_passthru.
#
#         * Intercepted requests which fail verification are sent
#           to the client original destination instead of DIRECT.
#           This overrides 'client_dst_passthru off'.
#
#        For now suspicious intercepted CONNECT requests are always
#        responded to with an HTTP 409 (Conflict) error page.
#
#
#    SECURITY NOTE:
#
#    As described in CVE-2009-0801 when the Host: header alone is used
#    to determine the destination of a request it becomes trivial for
#    malicious scripts on remote websites to bypass browser same-origin
#    security policy and sandboxing protections.
#
#    The cause of this is that such applets are allowed to perform their
#    own HTTP stack, in which case the same-origin policy of the browser
#    sandbox only verifies that the applet tries to contact the same IP
#    as from where it was loaded at the IP level. The Host: header may
#    be different from the connected IP and approved origin.
#
#Default:
# host_verify_strict off

#  TAG: client_dst_passthru
#    With NAT or TPROXY intercepted traffic Squid may pass the request
#    directly to the original client destination IP or seek a faster
#    source using the HTTP Host header.
#
#    Using Host to locate alternative servers can provide faster
#    connectivity with a range of failure recovery options.
#    But can also lead to connectivity trouble when the client and
#    server are attempting stateful interactions unaware of the proxy.
#
#    This option (on by default) prevents alternative DNS entries being
#    located to send intercepted traffic DIRECT to an origin server.
#    The clients original destination IP and port will be used instead.
#
#    Regardless of this option setting, when dealing with intercepted
#    traffic Squid will verify the Host: header and any traffic which
#    fails Host verification will be treated as if this option were ON.
#
#    see host_verify_strict for details on the verification process.
#Default:
# client_dst_passthru on

# TLS OPTIONS
# -----------------------------------------------------------------------------

#  TAG: tls_outgoing_options
#    disable        Do not support https:// URLs.
#
#    cert=/path/to/client/certificate
#            A client X.509 certificate to use when connecting.
#
#    key=/path/to/client/private_key
#            The private key corresponding to the cert= above.
#
#            If key= is not specified cert= is assumed to
#            reference a PEM file containing both the certificate
#            and private key.
#
#    cipher=...    The list of valid TLS ciphers to use.
#
#    min-version=1.N
#            The minimum TLS protocol version to permit.
#            To control SSLv3 use the options= parameter.
#            Supported Values: 1.0 (default), 1.1, 1.2, 1.3
#
#    options=...    Specify various TLS/SSL implementation options.
#
#            OpenSSL options most important are:
#
#                NO_SSLv3    Disallow the use of SSLv3
#
#                SINGLE_DH_USE
#                      Always create a new key when using
#                      temporary/ephemeral DH key exchanges
#
#                NO_TICKET
#                      Disable use of RFC5077 session tickets.
#                      Some servers may have problems
#                      understanding the TLS extension due
#                      to ambiguous specification in RFC4507.
#
#                ALL       Enable various bug workarounds
#                      suggested as "harmless" by OpenSSL
#                      Be warned that this reduces SSL/TLS
#                      strength to some attacks.
#
#                See the OpenSSL SSL_CTX_set_options documentation
#                for a more complete list.
#
#            GnuTLS options most important are:
#
#                %NO_TICKETS
#                      Disable use of RFC5077 session tickets.
#                      Some servers may have problems
#                      understanding the TLS extension due
#                      to ambiguous specification in RFC4507.
#
#                See the GnuTLS Priority Strings documentation
#                for a more complete list.
#                http://www.gnutls.org/manual/gnutls.html#Priority-Strings
#
#
#    cafile=        PEM file containing CA certificates to use when verifying
#            the peer certificate. May be repeated to load multiple files.
#
#    capath=        A directory containing additional CA certificates to
#            use when verifying the peer certificate.
#            Requires OpenSSL or LibreSSL.
#
#    crlfile=...     A certificate revocation list file to use when
#            verifying the peer certificate.
#
#    flags=...    Specify various flags modifying the TLS implementation:
#
#            DONT_VERIFY_PEER
#                Accept certificates even if they fail to
#                verify.
#            DONT_VERIFY_DOMAIN
#                Don't verify the peer certificate
#                matches the server name
#
#    default-ca[=off]
#            Whether to use the system Trusted CAs. Default is ON.
#
#    domain=     The peer name as advertised in its certificate.
#            Used for verifying the correctness of the received peer
#            certificate. If not specified the peer hostname will be
#            used.
#Default:
# tls_outgoing_options min-version=1.0

# SSL OPTIONS
# -----------------------------------------------------------------------------

#  TAG: ssl_unclean_shutdown
# Note: This option is only available if Squid is rebuilt with the
#       --with-openssl
#
#    Some browsers (especially MSIE) bugs out on SSL shutdown
#    messages.
#Default:
# ssl_unclean_shutdown off

#  TAG: ssl_engine
# Note: This option is only available if Squid is rebuilt with the
#       --with-openssl
#
#    The OpenSSL engine to use. You will need to set this if you
#    would like to use hardware SSL acceleration for example.
#
#    Note: OpenSSL 3.0 and newer do not provide Engine support.
#Default:
# none

#  TAG: sslproxy_session_ttl
# Note: This option is only available if Squid is rebuilt with the
#       --with-openssl
#
#    Sets the timeout value for SSL sessions
#Default:
# sslproxy_session_ttl 300

#  TAG: sslproxy_session_cache_size
# Note: This option is only available if Squid is rebuilt with the
#       --with-openssl
#
#        Sets the cache size to use for ssl session
#Default:
# sslproxy_session_cache_size 2 MB

#  TAG: sslproxy_foreign_intermediate_certs
# Note: This option is only available if Squid is rebuilt with the
#       --with-openssl
#
#    Many origin servers fail to send their full server certificate
#    chain for verification, assuming the client already has or can
#    easily locate any missing intermediate certificates.
#
#    Squid uses the certificates from the specified file to fill in
#    these missing chains when trying to validate origin server
#    certificate chains.
#
#    The file is expected to contain zero or more PEM-encoded
#    intermediate certificates. These certificates are not treated
#    as trusted root certificates, and any self-signed certificate in
#    this file will be ignored.
#Default:
# none

#  TAG: sslproxy_cert_sign_hash
# Note: This option is only available if Squid is rebuilt with the
#       --with-openssl
#
#    Sets the hashing algorithm to use when signing generated certificates.
#    Valid algorithm names depend on the OpenSSL library used. The following
#    names are usually available: sha1, sha256, sha512, and md5. Please see
#    your OpenSSL library manual for the available hashes. By default, Squids
#    that support this option use sha256 hashes.
#
#    Squid does not forcefully purge cached certificates that were generated
#    with an algorithm other than the currently configured one. They remain
#    in the cache, subject to the regular cache eviction policy, and become
#    useful if the algorithm changes again.
#Default:
# none

#  TAG: ssl_bump
# Note: This option is only available if Squid is rebuilt with the
#       --with-openssl
#
#    This option is consulted when a CONNECT request is received on
#    an http_port (or a new connection is intercepted at an
#    https_port), provided that port was configured with an ssl-bump
#    flag. The subsequent data on the connection is either treated as
#    HTTPS and decrypted OR tunneled at TCP level without decryption,
#    depending on the first matching bumping "action".
#
#    ssl_bump <action> [!]acl ...
#
#    The following bumping actions are currently supported:
#
#        splice
#        Become a TCP tunnel without decrypting proxied traffic.
#        This is the default action.
#
#        bump
#        When used on step SslBump1, establishes a secure connection
#        with the client first, then connect to the server.
#        When used on step SslBump2 or SslBump3, establishes a secure
#        connection with the server and, using a mimicked server
#        certificate, with the client.
#
#        peek
#        Receive client (step SslBump1) or server (step SslBump2)
#        certificate while preserving the possibility of splicing the
#        connection. Peeking at the server certificate (during step 2)
#        usually precludes bumping of the connection at step 3.
#
#        stare
#        Receive client (step SslBump1) or server (step SslBump2)
#        certificate while preserving the possibility of bumping the
#        connection. Staring at the server certificate (during step 2)
#        usually precludes splicing of the connection at step 3.
#
#        terminate
#        Close client and server connections.
#
#    Backward compatibility actions available at step SslBump1:
#
#        client-first
#        Bump the connection. Establish a secure connection with the
#        client first, then connect to the server. This old mode does
#        not allow Squid to mimic server SSL certificate and does not
#        work with intercepted SSL connections.
#
#        server-first
#        Bump the connection. Establish a secure connection with the
#        server first, then establish a secure connection with the
#        client, using a mimicked server certificate. Works with both
#        CONNECT requests and intercepted SSL connections, but does
#        not allow to make decisions based on SSL handshake info.
#
#        peek-and-splice
#        Decide whether to bump or splice the connection based on
#        client-to-squid and server-to-squid SSL hello messages.
#        XXX: Remove.
#
#        none
#        Same as the "splice" action.
#
#    All ssl_bump rules are evaluated at each of the supported bumping
#    steps.  Rules with actions that are impossible at the current step are
#    ignored. The first matching ssl_bump action wins and is applied at the
#    end of the current step. If no rules match, the splice action is used.
#    See the at_step ACL for a list of the supported SslBump steps.
#
#    This clause supports both fast and slow acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#
#    See also: http_port ssl-bump, https_port ssl-bump, and acl at_step.
#
#
#    # Example: Bump all TLS connections except those originating from
#    # localhost or those going to example.com.
#
#    acl broken_sites ssl::server_name .example.com
#    ssl_bump splice localhost
#    ssl_bump splice broken_sites
#    ssl_bump bump all
#Default:
# Become a TCP tunnel without decrypting proxied traffic.

#  TAG: sslproxy_cert_error
# Note: This option is only available if Squid is rebuilt with the
#       --with-openssl
#
#    Use this ACL to bypass server certificate validation errors.
#
#    For example, the following lines will bypass all validation errors
#    when talking to servers for example.com. All other
#    validation errors will result in ERR_SECURE_CONNECT_FAIL error.
#
#        acl BrokenButTrustedServers dstdomain example.com
#        sslproxy_cert_error allow BrokenButTrustedServers
#        sslproxy_cert_error deny all
#
#    This clause only supports fast acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#    Using slow acl types may result in server crashes
#
#    Without this option, all server certificate validation errors
#    terminate the transaction to protect Squid and the client.
#
#    SQUID_X509_V_ERR_INFINITE_VALIDATION error cannot be bypassed
#    but should not happen unless your OpenSSL library is buggy.
#
#    SECURITY WARNING:
#        Bypassing validation errors is dangerous because an
#        error usually implies that the server cannot be trusted
#        and the connection may be insecure.
#
#    See also: sslproxy_flags and DONT_VERIFY_PEER.
#Default:
# Server certificate errors terminate the transaction.

#  TAG: sslproxy_cert_sign
# Note: This option is only available if Squid is rebuilt with the
#       --with-openssl
#
#
#        sslproxy_cert_sign <signing algorithm> acl ...
#
#        The following certificate signing algorithms are supported:
#
#       signTrusted
#        Sign using the configured CA certificate which is usually
#        placed in and trusted by end-user browsers. This is the
#        default for trusted origin server certificates.
#
#       signUntrusted
#        Sign to guarantee an X509_V_ERR_CERT_UNTRUSTED browser error.
#        This is the default for untrusted origin server certificates
#        that are not self-signed (see ssl::certUntrusted).
#
#       signSelf
#        Sign using a self-signed certificate with the right CN to
#        generate a X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT error in the
#        browser. This is the default for self-signed origin server
#        certificates (see ssl::certSelfSigned).
#
#    This clause only supports fast acl types.
#
#    When sslproxy_cert_sign acl(s) match, Squid uses the corresponding
#    signing algorithm to generate the certificate and ignores all
#    subsequent sslproxy_cert_sign options (the first match wins). If no
#    acl(s) match, the default signing algorithm is determined by errors
#    detected when obtaining and validating the origin server certificate.
#
#    WARNING: SQUID_X509_V_ERR_DOMAIN_MISMATCH and ssl:certDomainMismatch can
#    be used with sslproxy_cert_adapt, but if and only if Squid is bumping a
#    CONNECT request that carries a domain name. In all other cases (CONNECT
#    to an IP address or an intercepted SSL connection), Squid cannot detect
#    the domain mismatch at certificate generation time when
#    bump-server-first is used.
#Default:
# none

#  TAG: sslproxy_cert_adapt
# Note: This option is only available if Squid is rebuilt with the
#       --with-openssl
#
#
#    sslproxy_cert_adapt <adaptation algorithm> acl ...
#
#    The following certificate adaptation algorithms are supported:
#
#       setValidAfter
#        Sets the "Not After" property to the "Not After" property of
#        the CA certificate used to sign generated certificates.
#
#       setValidBefore
#        Sets the "Not Before" property to the "Not Before" property of
#        the CA certificate used to sign generated certificates.
#
#       setCommonName or setCommonName{CN}
#        Sets Subject.CN property to the host name specified as a
#        CN parameter or, if no explicit CN parameter was specified,
#        extracted from the CONNECT request. It is a misconfiguration
#        to use setCommonName without an explicit parameter for
#        intercepted or tproxied SSL connections.
#
#    This clause only supports fast acl types.
#
#    Squid first groups sslproxy_cert_adapt options by adaptation algorithm.
#    Within a group, when sslproxy_cert_adapt acl(s) match, Squid uses the
#    corresponding adaptation algorithm to generate the certificate and
#    ignores all subsequent sslproxy_cert_adapt options in that algorithm's
#    group (i.e., the first match wins within each algorithm group). If no
#    acl(s) match, the default mimicking action takes place.
#
#    WARNING: SQUID_X509_V_ERR_DOMAIN_MISMATCH and ssl:certDomainMismatch can
#    be used with sslproxy_cert_adapt, but if and only if Squid is bumping a
#    CONNECT request that carries a domain name. In all other cases (CONNECT
#    to an IP address or an intercepted SSL connection), Squid cannot detect
#    the domain mismatch at certificate generation time when
#    bump-server-first is used.
#Default:
# none

#  TAG: sslpassword_program
# Note: This option is only available if Squid is rebuilt with the
#       --with-openssl
#
#    Specify a program used for entering SSL key passphrases
#    when using encrypted SSL certificate keys. If not specified
#    keys must either be unencrypted, or Squid started with the -N
#    option to allow it to query interactively for the passphrase.
#
#    The key file name is given as argument to the program allowing
#    selection of the right password if you have multiple encrypted
#    keys.
#Default:
# none

# OPTIONS RELATING TO EXTERNAL SSL_CRTD
# -----------------------------------------------------------------------------

#  TAG: sslcrtd_program
# Note: This option is only available if Squid is rebuilt with the
#       --enable-ssl-crtd
#
#    Specify the location and options of the executable for certificate
#    generator.
#
#    /usr/lib/squid/security_file_certgen program can use a disk cache to improve response
#    times on repeated requests. To enable caching, specify -s and -M
#    parameters. If those parameters are not given, the program generates
#    a new certificate on every request.
#
#    For more information use:
#        /usr/lib/squid/security_file_certgen -h
#Default:
# sslcrtd_program /usr/lib/squid/security_file_certgen -s /var/spool/squid/ssl_db -M 4MB

#  TAG: sslcrtd_children
# Note: This option is only available if Squid is rebuilt with the
#       --enable-ssl-crtd
#
#    Specifies the maximum number of certificate generation processes that
#    Squid may spawn (numberofchildren) and several related options. Using
#    too few of these helper processes (a.k.a. "helpers") creates request
#    queues. Using too many helpers wastes your system resources. Squid
#    does not support spawning more than 32 helpers.
#
#    Usage: numberofchildren [option]...
#
#    The startup= and idle= options allow some measure of skew in your
#    tuning.
#
#        startup=N
#
#    Sets the minimum number of processes to spawn when Squid
#    starts or reconfigures. When set to zero the first request will
#    cause spawning of the first child process to handle it.
#
#    Starting too few children temporary slows Squid under load while it
#    tries to spawn enough additional processes to cope with traffic.
#
#        idle=N
#
#    Sets a minimum of how many processes Squid is to try and keep available
#    at all times. When traffic begins to rise above what the existing
#    processes can handle this many more will be spawned up to the maximum
#    configured. A minimum setting of 1 is required.
#
#        queue-size=N
#
#    Sets the maximum number of queued requests. A request is queued when
#    no existing child is idle and no new child can be started due to
#    numberofchildren limit. If the queued requests exceed queue size for
#    more than 3 minutes squid aborts its operation. The default value is
#    set to 2*numberofchildren.
#
#    You must have at least one ssl_crtd process.
#Default:
# sslcrtd_children 32 startup=5 idle=1

#  TAG: sslcrtvalidator_program
# Note: This option is only available if Squid is rebuilt with the
#       --with-openssl
#
#    Specify the location and options of the executable for ssl_crt_validator
#    process.
#
#    Usage:  sslcrtvalidator_program [ttl=n] [cache=n] path ...
#
#    Options:
#      ttl=n         TTL in seconds for cached results. The default is 60 secs
#      cache=n       limit the result cache size. The default value is 2048
#Default:
# none

#  TAG: sslcrtvalidator_children
# Note: This option is only available if Squid is rebuilt with the
#       --with-openssl
#
#    Specifies the maximum number of certificate validation processes that
#    Squid may spawn (numberofchildren) and several related options. Using
#    too few of these helper processes (a.k.a. "helpers") creates request
#    queues. Using too many helpers wastes your system resources. Squid
#    does not support spawning more than 32 helpers.
#
#    Usage: numberofchildren [option]...
#
#    The startup= and idle= options allow some measure of skew in your
#    tuning.
#
#        startup=N
#
#    Sets the minimum number of processes to spawn when Squid
#    starts or reconfigures. When set to zero the first request will
#    cause spawning of the first child process to handle it.
#
#    Starting too few children temporary slows Squid under load while it
#    tries to spawn enough additional processes to cope with traffic.
#
#        idle=N
#
#    Sets a minimum of how many processes Squid is to try and keep available
#    at all times. When traffic begins to rise above what the existing
#    processes can handle this many more will be spawned up to the maximum
#    configured. A minimum setting of 1 is required.
#
#        concurrency=
#
#    The number of requests each certificate validator helper can handle in
#    parallel. A value of 0 indicates the certficate validator does not
#    support concurrency. Defaults to 1.
#
#    When this directive is set to a value >= 1 then the protocol
#    used to communicate with the helper is modified to include
#    a request ID in front of the request/response. The request
#    ID from the request must be echoed back with the response
#    to that request.
#
#        queue-size=N
#
#    Sets the maximum number of queued requests. A request is queued when
#    no existing child can accept it due to concurrency limit and no new
#    child can be started due to numberofchildren limit. If the queued
#    requests exceed queue size for more than 3 minutes squid aborts its
#    operation. The default value is set to 2*numberofchildren.
#
#    You must have at least one ssl_crt_validator process.
#Default:
# sslcrtvalidator_children 32 startup=5 idle=1 concurrency=1

# OPTIONS WHICH AFFECT THE NEIGHBOR SELECTION ALGORITHM
# -----------------------------------------------------------------------------

#  TAG: cache_peer
#    To specify other caches in a hierarchy, use the format:
#
#        cache_peer hostname type http-port icp-port [options]
#
#    For example,
#
#    #                                        proxy  icp
#    #          hostname             type     port   port  options
#    #          -------------------- -------- ----- -----  -----------
#    cache_peer parent.foo.net       parent    3128  3130  default
#    cache_peer sib1.foo.net         sibling   3128  3130  proxy-only
#    cache_peer sib2.foo.net         sibling   3128  3130  proxy-only
#    cache_peer example.com          parent    80       0  default
#    cache_peer cdn.example.com      sibling   3128     0
#
#          type:    either 'parent', 'sibling', or 'multicast'.
#
#    proxy-port:    The port number where the peer accept HTTP requests.
#            For other Squid proxies this is usually 3128
#            For web servers this is usually 80
#
#      icp-port:    Used for querying neighbor caches about objects.
#            Set to 0 if the peer does not support ICP or HTCP.
#            See ICP and HTCP options below for additional details.
#
#
#    ==== ICP OPTIONS ====
#
#    You MUST also set icp_port and icp_access explicitly when using these options.
#    The defaults will prevent peer traffic using ICP.
#
#
#    no-query    Disable ICP queries to this neighbor.
#
#    multicast-responder
#            Indicates the named peer is a member of a multicast group.
#            ICP queries will not be sent directly to the peer, but ICP
#            replies will be accepted from it.
#
#    closest-only    Indicates that, for ICP_OP_MISS replies, we'll only forward
#            CLOSEST_PARENT_MISSes and never FIRST_PARENT_MISSes.
#
#    background-ping
#            To only send ICP queries to this neighbor infrequently.
#            This is used to keep the neighbor round trip time updated
#            and is usually used in conjunction with weighted-round-robin.
#
#
#    ==== HTCP OPTIONS ====
#
#    You MUST also set htcp_port and htcp_access explicitly when using these options.
#    The defaults will prevent peer traffic using HTCP.
#
#
#    htcp        Send HTCP, instead of ICP, queries to the neighbor.
#            You probably also want to set the "icp-port" to 4827
#            instead of 3130. This directive accepts a comma separated
#            list of options described below.
#
#    htcp=oldsquid    Send HTCP to old Squid versions (2.5 or earlier).
#
#    htcp=no-clr    Send HTCP to the neighbor but without
#            sending any CLR requests.  This cannot be used with
#            only-clr.
#
#    htcp=only-clr    Send HTCP to the neighbor but ONLY CLR requests.
#            This cannot be used with no-clr.
#
#    htcp=no-purge-clr
#            Send HTCP to the neighbor including CLRs but only when
#            they do not result from PURGE requests.
#
#    htcp=forward-clr
#            Forward any HTCP CLR requests this proxy receives to the peer.
#
#
#    ==== PEER SELECTION METHODS ====
#
#    The default peer selection method is ICP, with the first responding peer
#    being used as source. These options can be used for better load balancing.
#
#
#    default        This is a parent cache which can be used as a "last-resort"
#            if a peer cannot be located by any of the peer-selection methods.
#            If specified more than once, only the first is used.
#
#    round-robin    Load-Balance parents which should be used in a round-robin
#            fashion in the absence of any ICP queries.
#            weight=N can be used to add bias.
#
#    weighted-round-robin
#            Load-Balance parents which should be used in a round-robin
#            fashion with the frequency of each parent being based on the
#            round trip time. Closer parents are used more often.
#            Usually used for background-ping parents.
#            weight=N can be used to add bias.
#
#    carp        Load-Balance parents which should be used as a CARP array.
#            The requests will be distributed among the parents based on the
#            CARP load balancing hash function based on their weight.
#
#    userhash    Load-balance parents based on the client proxy_auth or ident username.
#
#    sourcehash    Load-balance parents based on the client source IP.
#
#    multicast-siblings
#            To be used only for cache peers of type "multicast".
#            ALL members of this multicast group have "sibling"
#            relationship with it, not "parent".  This is to a multicast
#            group when the requested object would be fetched only from
#            a "parent" cache, anyway.  It's useful, e.g., when
#            configuring a pool of redundant Squid proxies, being
#            members of the same multicast group.
#
#
#    ==== PEER SELECTION OPTIONS ====
#
#    weight=N    use to affect the selection of a peer during any weighted
#            peer-selection mechanisms.
#            The weight must be an integer; default is 1,
#            larger weights are favored more.
#            This option does not affect parent selection if a peering
#            protocol is not in use.
#
#    basetime=N    Specify a base amount to be subtracted from round trip
#            times of parents.
#            It is subtracted before division by weight in calculating
#            which parent to fectch from. If the rtt is less than the
#            base time the rtt is set to a minimal value.
#
#    ttl=N        Specify a TTL to use when sending multicast ICP queries
#            to this address.
#            Only useful when sending to a multicast group.
#            Because we don't accept ICP replies from random
#            hosts, you must configure other group members as
#            peers with the 'multicast-responder' option.
#
#    no-delay    To prevent access to this neighbor from influencing the
#            delay pools.
#
#    digest-url=URL    Tell Squid to fetch the cache digest (if digests are
#            enabled) for this host from the specified URL rather
#            than the Squid default location.
#
#
#    ==== CARP OPTIONS ====
#
#    carp-key=key-specification
#            use a different key than the full URL to hash against the peer.
#            the key-specification is a comma-separated list of the keywords
#            scheme, host, port, path, params
#            Order is not important.
#
#    ==== ACCELERATOR / REVERSE-PROXY OPTIONS ====
#
#    originserver    Causes this parent to be contacted as an origin server.
#            Meant to be used in accelerator setups when the peer
#            is a web server.
#
#    forceddomain=name
#            Set the Host header of requests forwarded to this peer.
#            Useful in accelerator setups where the server (peer)
#            expects a certain domain name but clients may request
#            others. ie example.com or www.example.com
#
#    no-digest    Disable request of cache digests.
#
#    no-netdb-exchange
#            Disables requesting ICMP RTT database (NetDB).
#
#
#    ==== AUTHENTICATION OPTIONS ====
#
#    login=user:password
#            If this is a personal/workgroup proxy and your parent
#            requires proxy authentication.
#
#            Note: The string can include URL escapes (i.e. %20 for
#            spaces). This also means % must be written as %%.
#
#    login=PASSTHRU
#            Send login details received from client to this peer.
#            Both Proxy- and WWW-Authorization headers are passed
#            without alteration to the peer.
#            Authentication is not required by Squid for this to work.
#
#            Note: This will pass any form of authentication but
#            only Basic auth will work through a proxy unless the
#            connection-auth options are also used.
#
#    login=PASS    Send login details received from client to this peer.
#            Authentication is not required by this option.
#
#            If there are no client-provided authentication headers
#            to pass on, but username and password are available
#            from an external ACL user= and password= result tags
#            they may be sent instead.
#
#            Note: To combine this with proxy_auth both proxies must
#            share the same user database as HTTP only allows for
#            a single login (one for proxy, one for origin server).
#            Also be warned this will expose your users proxy
#            password to the peer. USE WITH CAUTION
#
#    login=*:password
#            Send the username to the upstream cache, but with a
#            fixed password. This is meant to be used when the peer
#            is in another administrative domain, but it is still
#            needed to identify each user.
#            The star can optionally be followed by some extra
#            information which is added to the username. This can
#            be used to identify this proxy to the peer, similar to
#            the login=username:password option above.
#
#    login=NEGOTIATE
#            If this is a personal/workgroup proxy and your parent
#            requires a secure proxy authentication.
#            The first principal from the default keytab or defined by
#            the environment variable KRB5_KTNAME will be used.
#
#            WARNING: The connection may transmit requests from multiple
#            clients. Negotiate often assumes end-to-end authentication
#            and a single-client. Which is not strictly true here.
#
#    login=NEGOTIATE:principal_name
#            If this is a personal/workgroup proxy and your parent
#            requires a secure proxy authentication.
#            The principal principal_name from the default keytab or
#            defined by the environment variable KRB5_KTNAME will be
#            used.
#
#            WARNING: The connection may transmit requests from multiple
#            clients. Negotiate often assumes end-to-end authentication
#            and a single-client. Which is not strictly true here.
#
#    connection-auth=on|off
#            Tell Squid that this peer does or not support Microsoft
#            connection oriented authentication, and any such
#            challenges received from there should be ignored.
#            Default is auto to automatically determine the status
#            of the peer.
#
#    auth-no-keytab
#            Do not use a keytab to authenticate to a peer when
#            login=NEGOTIATE is specified. Let the GSSAPI
#            implementation determine which already existing
#            credentials cache to use instead.
#
#
#    ==== SSL / HTTPS / TLS OPTIONS ====
#
#    tls        Encrypt connections to this peer with TLS.
#
#    sslcert=/path/to/ssl/certificate
#            A client X.509 certificate to use when connecting to
#            this peer.
#
#    sslkey=/path/to/ssl/key
#            The private key corresponding to sslcert above.
#
#            If sslkey= is not specified sslcert= is assumed to
#            reference a PEM file containing both the certificate
#            and private key.
#
#    Notes:
#
#    On Debian/Ubuntu systems a default snakeoil certificate is
#    available in /etc/ssl and users can set:
#
#        sslcert=/etc/ssl/certs/ssl-cert-snakeoil.pem
#
#    and
#
#        sslkey=/etc/ssl/private/ssl-cert-snakeoil.key
#
#    for testing.
#
#    sslcipher=...    The list of valid SSL ciphers to use when connecting
#            to this peer.
#
#    tls-min-version=1.N
#            The minimum TLS protocol version to permit. To control
#            SSLv3 use the tls-options= parameter.
#            Supported Values: 1.0 (default), 1.1, 1.2
#
#    tls-options=...    Specify various TLS implementation options.
#
#            OpenSSL options most important are:
#
#                NO_SSLv3    Disallow the use of SSLv3
#
#                SINGLE_DH_USE
#                      Always create a new key when using
#                      temporary/ephemeral DH key exchanges
#
#                NO_TICKET
#                      Disable use of RFC5077 session tickets.
#                      Some servers may have problems
#                      understanding the TLS extension due
#                      to ambiguous specification in RFC4507.
#
#                ALL       Enable various bug workarounds
#                      suggested as "harmless" by OpenSSL
#                      Be warned that this reduces SSL/TLS
#                      strength to some attacks.
#
#            See the OpenSSL SSL_CTX_set_options documentation for a
#            more complete list.
#
#            GnuTLS options most important are:
#
#                %NO_TICKETS
#                      Disable use of RFC5077 session tickets.
#                      Some servers may have problems
#                      understanding the TLS extension due
#                      to ambiguous specification in RFC4507.
#
#                See the GnuTLS Priority Strings documentation
#                for a more complete list.
#                http://www.gnutls.org/manual/gnutls.html#Priority-Strings
#
#    tls-cafile=    PEM file containing CA certificates to use when verifying
#            the peer certificate. May be repeated to load multiple files.
#
#    sslcapath=...    A directory containing additional CA certificates to
#            use when verifying the peer certificate.
#            Requires OpenSSL or LibreSSL.
#
#    sslcrlfile=...     A certificate revocation list file to use when
#            verifying the peer certificate.
#
#    sslflags=...    Specify various flags modifying the SSL implementation:
#
#            DONT_VERIFY_PEER
#                Accept certificates even if they fail to
#                verify.
#
#            DONT_VERIFY_DOMAIN
#                Don't verify the peer certificate
#                matches the server name
#
#    ssldomain=     The peer name as advertised in it's certificate.
#            Used for verifying the correctness of the received peer
#            certificate. If not specified the peer hostname will be
#            used.
#
#    front-end-https[=off|on|auto]
#            Enable the "Front-End-Https: On" header needed when
#            using Squid as a SSL frontend in front of Microsoft OWA.
#            See MS KB document Q307347 for details on this header.
#            If set to auto the header will only be added if the
#            request is forwarded as a https:// URL.
#
#    tls-default-ca[=off]
#            Whether to use the system Trusted CAs. Default is ON.
#
#    tls-no-npn    Do not use the TLS NPN extension to advertise HTTP/1.1.
#
#    ==== GENERAL OPTIONS ====
#
#    connect-timeout=N
#            A peer-specific connect timeout.
#            Also see the peer_connect_timeout directive.
#
#    connect-fail-limit=N
#            How many times connecting to a peer must fail before
#            it is marked as down. Standby connection failures
#            count towards this limit. Default is 10.
#
#    allow-miss    Disable Squid's use of only-if-cached when forwarding
#            requests to siblings. This is primarily useful when
#            icp_hit_stale is used by the sibling. Excessive use
#            of this option may result in forwarding loops. One way
#            to prevent peering loops when using this option, is to
#            deny cache peer usage on requests from a peer:
#            acl fromPeer ...
#            cache_peer_access peerName deny fromPeer
#
#    max-conn=N     Limit the number of concurrent connections the Squid
#            may open to this peer, including already opened idle
#            and standby connections. There is no peer-specific
#            connection limit by default.
#
#            A peer exceeding the limit is not used for new
#            requests unless a standby connection is available.
#
#            max-conn currently works poorly with idle persistent
#            connections: When a peer reaches its max-conn limit,
#            and there are idle persistent connections to the peer,
#            the peer may not be selected because the limiting code
#            does not know whether Squid can reuse those idle
#            connections.
#
#    standby=N    Maintain a pool of N "hot standby" connections to an
#            UP peer, available for requests when no idle
#            persistent connection is available (or safe) to use.
#            By default and with zero N, no such pool is maintained.
#            N must not exceed the max-conn limit (if any).
#
#            At start or after reconfiguration, Squid opens new TCP
#            standby connections until there are N connections
#            available and then replenishes the standby pool as
#            opened connections are used up for requests. A used
#            connection never goes back to the standby pool, but
#            may go to the regular idle persistent connection pool
#            shared by all peers and origin servers.
#
#            Squid never opens multiple new standby connections
#            concurrently.  This one-at-a-time approach minimizes
#            flooding-like effect on peers. Furthermore, just a few
#            standby connections should be sufficient in most cases
#            to supply most new requests with a ready-to-use
#            connection.
#
#            Standby connections obey server_idle_pconn_timeout.
#            For the feature to work as intended, the peer must be
#            configured to accept and keep them open longer than
#            the idle timeout at the connecting Squid, to minimize
#            race conditions typical to idle used persistent
#            connections. Default request_timeout and
#            server_idle_pconn_timeout values ensure such a
#            configuration.
#
#    name=xxx    Unique name for the peer.
#            Required if you have multiple peers on the same host
#            but different ports.
#            This name can be used in cache_peer_access and similar
#            directives to identify the peer.
#            Can be used by outgoing access controls through the
#            peername ACL type.
#
#    no-tproxy    Do not use the client-spoof TPROXY support when forwarding
#            requests to this peer. Use normal address selection instead.
#            This overrides the spoof_client_ip ACL.
#
#    proxy-only    objects fetched from the peer will not be stored locally.
#
#Default:
# none

#  TAG: cache_peer_access
#    Restricts usage of cache_peer proxies.
#
#    Usage:
#        cache_peer_access peer-name allow|deny [!]aclname ...
#
#    For the required peer-name parameter, use either the value of the
#    cache_peer name=value parameter or, if name=value is missing, the
#    cache_peer hostname parameter.
#
#    This directive narrows down the selection of peering candidates, but
#    does not determine the order in which the selected candidates are
#    contacted. That order is determined by the peer selection algorithms
#    (see PEER SELECTION sections in the cache_peer documentation).
#
#    If a deny rule matches, the corresponding peer will not be contacted
#    for the current transaction -- Squid will not send ICP queries and
#    will not forward HTTP requests to that peer. An allow match leaves
#    the corresponding peer in the selection. The first match for a given
#    peer wins for that peer.
#
#    The relative order of cache_peer_access directives for the same peer
#    matters. The relative order of any two cache_peer_access directives
#    for different peers does not matter. To ease interpretation, it is a
#    good idea to group cache_peer_access directives for the same peer
#    together.
#
#    A single cache_peer_access directive may be evaluated multiple times
#    for a given transaction because individual peer selection algorithms
#    may check it independently from each other. These redundant checks
#    may be optimized away in future Squid versions.
#
#    This clause only supports fast acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#
#Default:
# No peer usage restrictions.

#  TAG: neighbor_type_domain
#    Modify the cache_peer neighbor type when passing requests
#    about specific domains to the peer.
#
#    Usage:
#         neighbor_type_domain neighbor parent|sibling domain domain ...
#
#    For example:
#        cache_peer foo.example.com parent 3128 3130
#        neighbor_type_domain foo.example.com sibling .au .de
#
#    The above configuration treats all requests to foo.example.com as a
#    parent proxy unless the request is for a .au or .de ccTLD domain name.
#Default:
# The peer type from cache_peer directive is used for all requests to that peer.

#  TAG: dead_peer_timeout    (seconds)
#    This controls how long Squid waits to declare a peer cache
#    as "dead."  If there are no ICP replies received in this
#    amount of time, Squid will declare the peer dead and not
#    expect to receive any further ICP replies.  However, it
#    continues to send ICP queries, and will mark the peer as
#    alive upon receipt of the first subsequent ICP reply.
#
#    This timeout also affects when Squid expects to receive ICP
#    replies from peers.  If more than 'dead_peer' seconds have
#    passed since the last ICP reply was received, Squid will not
#    expect to receive an ICP reply on the next query.  Thus, if
#    your time between requests is greater than this timeout, you
#    will see a lot of requests sent DIRECT to origin servers
#    instead of to your parents.
#Default:
# dead_peer_timeout 10 seconds

#  TAG: forward_max_tries
#    Limits the number of attempts to forward the request.
#
#    For the purpose of this limit, Squid counts all high-level request
#    forwarding attempts, including any same-destination retries after
#    certain persistent connection failures and any attempts to use a
#    different peer. However, low-level connection reopening attempts
#    (enabled using connect_retries) are not counted.
#
#    See also: forward_timeout and connect_retries.
#Default:
# forward_max_tries 25

# MEMORY CACHE OPTIONS
# -----------------------------------------------------------------------------

#  TAG: cache_mem    (bytes)
#    NOTE: THIS PARAMETER DOES NOT SPECIFY THE MAXIMUM PROCESS SIZE.
#    IT ONLY PLACES A LIMIT ON HOW MUCH ADDITIONAL MEMORY SQUID WILL
#    USE AS A MEMORY CACHE OF OBJECTS. SQUID USES MEMORY FOR OTHER
#    THINGS AS WELL. SEE THE SQUID FAQ SECTION 8 FOR DETAILS.
#
#    'cache_mem' specifies the ideal amount of memory to be used
#    for:
#        * In-Transit objects
#        * Hot Objects
#        * Negative-Cached objects
#
#    Data for these objects are stored in 4 KB blocks.  This
#    parameter specifies the ideal upper limit on the total size of
#    4 KB blocks allocated.  In-Transit objects take the highest
#    priority.
#
#    In-transit objects have priority over the others.  When
#    additional space is needed for incoming data, negative-cached
#    and hot objects will be released.  In other words, the
#    negative-cached and hot objects will fill up any unused space
#    not needed for in-transit objects.
#
#    If circumstances require, this limit will be exceeded.
#    Specifically, if your incoming request rate requires more than
#    'cache_mem' of memory to hold in-transit objects, Squid will
#    exceed this limit to satisfy the new requests.  When the load
#    decreases, blocks will be freed until the high-water mark is
#    reached.  Thereafter, blocks will be used to store hot
#    objects.
#
#    If shared memory caching is enabled, Squid does not use the shared
#    cache space for in-transit objects, but they still consume as much
#    local memory as they need. For more details about the shared memory
#    cache, see memory_cache_shared.
#Default:
# cache_mem 256 MB

#  TAG: maximum_object_size_in_memory    (bytes)
#    Objects greater than this size will not be attempted to kept in
#    the memory cache. This should be set high enough to keep objects
#    accessed frequently in memory to improve performance whilst low
#    enough to keep larger objects from hoarding cache_mem.
#Default:
# maximum_object_size_in_memory 768 KB

#  TAG: memory_cache_shared    on|off
#    Controls whether the memory cache is shared among SMP workers.
#
#    The shared memory cache is meant to occupy cache_mem bytes and replace
#    the non-shared memory cache, although some entities may still be
#    cached locally by workers for now (e.g., internal and in-transit
#    objects may be served from a local memory cache even if shared memory
#    caching is enabled).
#
#    By default, the memory cache is shared if and only if all of the
#    following conditions are satisfied: Squid runs in SMP mode with
#    multiple workers, cache_mem is positive, and Squid environment
#    supports required IPC primitives (e.g., POSIX shared memory segments
#    and GCC-style atomic operations).
#
#    To avoid blocking locks, shared memory uses opportunistic algorithms
#    that do not guarantee that every cachable entity that could have been
#    shared among SMP workers will actually be shared.
#Default:
# "on" where supported if doing memory caching with multiple SMP workers.

#  TAG: memory_cache_mode disk
#    Controls which objects to keep in the memory cache (cache_mem)
#
#    always    Keep most recently fetched objects in memory (default)
#
#    disk    Only disk cache hits are kept in memory, which means
#        an object must first be cached on disk and then hit
#        a second time before cached in memory.
#
#    network    Only objects fetched from network is kept in memory
#Default:
# Keep the most recently fetched objects in memory

#  TAG: memory_replacement_policy
#    The memory replacement policy parameter determines which
#    objects are purged from memory when memory space is needed.
#
#    See cache_replacement_policy for details on algorithms.
#Default:
# memory_replacement_policy lru

# DISK CACHE OPTIONS
# -----------------------------------------------------------------------------

#  TAG: cache_replacement_policy
#    The cache replacement policy parameter determines which
#    objects are evicted (replaced) when disk space is needed.
#
#        lru       : Squid's original list based LRU policy
#        heap GDSF : Greedy-Dual Size Frequency
#        heap LFUDA: Least Frequently Used with Dynamic Aging
#        heap LRU  : LRU policy implemented using a heap
#
#    Applies to any cache_dir lines listed below this directive.
#
#    The LRU policies keeps recently referenced objects.
#
#    The heap GDSF policy optimizes object hit rate by keeping smaller
#    popular objects in cache so it has a better chance of getting a
#    hit.  It achieves a lower byte hit rate than LFUDA though since
#    it evicts larger (possibly popular) objects.
#
#    The heap LFUDA policy keeps popular objects in cache regardless of
#    their size and thus optimizes byte hit rate at the expense of
#    hit rate since one large, popular object will prevent many
#    smaller, slightly less popular objects from being cached.
#
#    Both policies utilize a dynamic aging mechanism that prevents
#    cache pollution that can otherwise occur with frequency-based
#    replacement policies.
#
#    NOTE: if using the LFUDA replacement policy you should increase
#    the value of maximum_object_size above its default of 4 MB to
#    to maximize the potential byte hit rate improvement of LFUDA.
#
#    For more information about the GDSF and LFUDA cache replacement
#    policies see http://www.hpl.hp.com/techreports/1999/HPL-1999-69.html
#    and http://fog.hpl.external.hp.com/techreports/98/HPL-98-173.html.
#Default:
# cache_replacement_policy lru

#  TAG: minimum_object_size    (bytes)
#    Objects smaller than this size will NOT be saved on disk.  The
#    value is specified in bytes, and the default is 0 KB, which
#    means all responses can be stored.
#Default:
# no limit

#  TAG: maximum_object_size    (bytes)
#    Set the default value for max-size parameter on any cache_dir.
#    The value is specified in bytes, and the default is 4 MB.
#
#    If you wish to get a high BYTES hit ratio, you should probably
#    increase this (one 32 MB object hit counts for 3200 10KB
#    hits).
#
#    If you wish to increase hit ratio more than you want to
#    save bandwidth you should leave this low.
#
#    NOTE: if using the LFUDA replacement policy you should increase
#    this value to maximize the byte hit rate improvement of LFUDA!
#    See cache_replacement_policy for a discussion of this policy.
#Default:
# maximum_object_size 4 MB

#  TAG: cache_dir
#    Format:
#        cache_dir Type Directory-Name Fs-specific-data [options]
#
#    You can specify multiple cache_dir lines to spread the
#    cache among different disk partitions.
#
#    Type specifies the kind of storage system to use. Only "ufs"
#    is built by default. To enable any of the other storage systems
#    see the --enable-storeio configure option.
#
#    'Directory' is a top-level directory where cache swap
#    files will be stored.  If you want to use an entire disk
#    for caching, this can be the mount-point directory.
#    The directory must exist and be writable by the Squid
#    process.  Squid will NOT create this directory for you.
#
#    In SMP configurations, cache_dir must not precede the workers option
#    and should use configuration macros or conditionals to give each
#    worker interested in disk caching a dedicated cache directory.
#
#
#    ====  The ufs store type  ====
#
#    "ufs" is the old well-known Squid storage format that has always
#    been there.
#
#    Usage:
#        cache_dir ufs Directory-Name Mbytes L1 L2 [options]
#
#    'Mbytes' is the amount of disk space (MB) to use under this
#    directory.  The default is 100 MB.  Change this to suit your
#    configuration.  Do NOT put the size of your disk drive here.
#    Instead, if you want Squid to use the entire disk drive,
#    subtract 20% and use that value.
#
#    'L1' is the number of first-level subdirectories which
#    will be created under the 'Directory'.  The default is 16.
#
#    'L2' is the number of second-level subdirectories which
#    will be created under each first-level directory.  The default
#    is 256.
#
#
#    ====  The aufs store type  ====
#
#    "aufs" uses the same storage format as "ufs", utilizing
#    POSIX-threads to avoid blocking the main Squid process on
#    disk-I/O. This was formerly known in Squid as async-io.
#
#    Usage:
#        cache_dir aufs Directory-Name Mbytes L1 L2 [options]
#
#    see argument descriptions under ufs above
#
#
#    ====  The diskd store type  ====
#
#    "diskd" uses the same storage format as "ufs", utilizing a
#    separate process to avoid blocking the main Squid process on
#    disk-I/O.
#
#    Usage:
#        cache_dir diskd Directory-Name Mbytes L1 L2 [options] [Q1=n] [Q2=n]
#
#    see argument descriptions under ufs above
#
#    Q1 specifies the number of unacknowledged I/O requests when Squid
#    stops opening new files. If this many messages are in the queues,
#    Squid won't open new files. Default is 64
#
#    Q2 specifies the number of unacknowledged messages when Squid
#    starts blocking.  If this many messages are in the queues,
#    Squid blocks until it receives some replies. Default is 72
#
#    When Q1 < Q2 (the default), the cache directory is optimized
#    for lower response time at the expense of a decrease in hit
#    ratio.  If Q1 > Q2, the cache directory is optimized for
#    higher hit ratio at the expense of an increase in response
#    time.
#
#
#    ====  The rock store type  ====
#
#    Usage:
#        cache_dir rock Directory-Name Mbytes [options]
#
#    The Rock Store type is a database-style storage. All cached
#    entries are stored in a "database" file, using fixed-size slots.
#    A single entry occupies one or more slots.
#
#    If possible, Squid using Rock Store creates a dedicated kid
#    process called "disker" to avoid blocking Squid worker(s) on disk
#    I/O. One disker kid is created for each rock cache_dir.  Diskers
#    are created only when Squid, running in daemon mode, has support
#    for the IpcIo disk I/O module.
#
#    swap-timeout=msec: Squid will not start writing a miss to or
#    reading a hit from disk if it estimates that the swap operation
#    will take more than the specified number of milliseconds. By
#    default and when set to zero, disables the disk I/O time limit
#    enforcement. Ignored when using blocking I/O module because
#    blocking synchronous I/O does not allow Squid to estimate the
#    expected swap wait time.
#
#    max-swap-rate=swaps/sec: Artificially limits disk access using
#    the specified I/O rate limit. Swap out requests that
#    would cause the average I/O rate to exceed the limit are
#    delayed. Individual swap in requests (i.e., hits or reads) are
#    not delayed, but they do contribute to measured swap rate and
#    since they are placed in the same FIFO queue as swap out
#    requests, they may wait longer if max-swap-rate is smaller.
#    This is necessary on file systems that buffer "too
#    many" writes and then start blocking Squid and other processes
#    while committing those writes to disk.  Usually used together
#    with swap-timeout to avoid excessive delays and queue overflows
#    when disk demand exceeds available disk "bandwidth". By default
#    and when set to zero, disables the disk I/O rate limit
#    enforcement. Currently supported by IpcIo module only.
#
#    slot-size=bytes: The size of a database "record" used for
#    storing cached responses. A cached response occupies at least
#    one slot and all database I/O is done using individual slots so
#    increasing this parameter leads to more disk space waste while
#    decreasing it leads to more disk I/O overheads. Should be a
#    multiple of your operating system I/O page size. Defaults to
#    16KBytes. A housekeeping header is stored with each slot and
#    smaller slot-sizes will be rejected. The header is smaller than
#    100 bytes.
#
#
#    ==== COMMON OPTIONS ====
#
#    no-store    no new objects should be stored to this cache_dir.
#
#    min-size=n    the minimum object size in bytes this cache_dir
#            will accept.  It's used to restrict a cache_dir
#            to only store large objects (e.g. AUFS) while
#            other stores are optimized for smaller objects
#            (e.g. Rock).
#            Defaults to 0.
#
#    max-size=n    the maximum object size in bytes this cache_dir
#            supports.
#            The value in maximum_object_size directive sets
#            the default unless more specific details are
#            available (ie a small store capacity).
#
#    Note: To make optimal use of the max-size limits you should order
#    the cache_dir lines with the smallest max-size value first.
#
#Default:
# No disk cache. Store cache ojects only in memory.
#
#  TAG: store_dir_select_algorithm
#    How Squid selects which cache_dir to use when the response
#    object will fit into more than one.
#
#    Regardless of which algorithm is used the cache_dir min-size
#    and max-size parameters are obeyed. As such they can affect
#    the selection algorithm by limiting the set of considered
#    cache_dir.
#
#    Algorithms:
#
#        least-load
#
#    This algorithm is suited to caches with similar cache_dir
#    sizes and disk speeds.
#
#    The disk with the least I/O pending is selected.
#    When there are multiple disks with the same I/O load ranking
#    the cache_dir with most available capacity is selected.
#
#    When a mix of cache_dir sizes are configured the faster disks
#    have a naturally lower I/O loading and larger disks have more
#    capacity. So space used to store objects and data throughput
#    may be very unbalanced towards larger disks.
#
#
#        round-robin
#
#    This algorithm is suited to caches with unequal cache_dir
#    disk sizes.
#
#    Each cache_dir is selected in a rotation. The next suitable
#    cache_dir is used.
#
#    Available cache_dir capacity is only considered in relation
#    to whether the object will fit and meets the min-size and
#    max-size parameters.
#
#    Disk I/O loading is only considered to prevent overload on slow
#    disks. This algorithm does not spread objects by size, so any
#    I/O loading per-disk may appear very unbalanced and volatile.
#
#    If several cache_dirs use similar min-size, max-size, or other
#    limits to to reject certain responses, then do not group such
#    cache_dir lines together, to avoid round-robin selection bias
#    towards the first cache_dir after the group. Instead, interleave
#    cache_dir lines from different groups. For example:
#
#        store_dir_select_algorithm round-robin
#        cache_dir rock /hdd1 ... min-size=100000
#        cache_dir rock /ssd1 ... max-size=99999
#        cache_dir rock /hdd2 ... min-size=100000
#        cache_dir rock /ssd2 ... max-size=99999
#        cache_dir rock /hdd3 ... min-size=100000
#        cache_dir rock /ssd3 ... max-size=99999
#Default:
# store_dir_select_algorithm least-load

#  TAG: max_open_disk_fds
#    To avoid having disk as the I/O bottleneck Squid can optionally
#    bypass the on-disk cache if more than this amount of disk file
#    descriptors are open.
#
#    A value of 0 indicates no limit.
#Default:
# no limit

#  TAG: cache_swap_low    (percent, 0-100)
#    The low-water mark for AUFS/UFS/diskd cache object eviction by
#    the cache_replacement_policy algorithm.
#
#    Removal begins when the swap (disk) usage of a cache_dir is
#    above this low-water mark and attempts to maintain utilization
#    near the low-water mark.
#
#    As swap utilization increases towards the high-water mark set
#    by cache_swap_high object eviction becomes more agressive.
#
#    The value difference in percentages between low- and high-water
#    marks represent an eviction rate of 300 objects per second and
#    the rate continues to scale in agressiveness by multiples of
#    this above the high-water mark.
#
#    Defaults are 90% and 95%. If you have a large cache, 5% could be
#    hundreds of MB. If this is the case you may wish to set these
#    numbers closer together.
#
#    See also cache_swap_high and cache_replacement_policy
#Default:
# cache_swap_low 90

#  TAG: cache_swap_high    (percent, 0-100)
#    The high-water mark for AUFS/UFS/diskd cache object eviction by
#    the cache_replacement_policy algorithm.
#
#    Removal begins when the swap (disk) usage of a cache_dir is
#    above the low-water mark set by cache_swap_low and attempts to
#    maintain utilization near the low-water mark.
#
#    As swap utilization increases towards this high-water mark object
#    eviction becomes more agressive.
#
#    The value difference in percentages between low- and high-water
#    marks represent an eviction rate of 300 objects per second and
#    the rate continues to scale in agressiveness by multiples of
#    this above the high-water mark.
#
#    Defaults are 90% and 95%. If you have a large cache, 5% could be
#    hundreds of MB. If this is the case you may wish to set these
#    numbers closer together.
#
#    See also cache_swap_low and cache_replacement_policy
#Default:
# cache_swap_high 95

# LOGFILE OPTIONS
# -----------------------------------------------------------------------------

#  TAG: logformat
#    Usage:
#
#    logformat <name> <format specification>
#
#    Defines an access log format.
#
#    The <format specification> is a string with embedded % format codes
#
#    % format codes all follow the same basic structure where all
#    components but the formatcode are optional and usually unnecessary,
#    especially when dealing with common codes.
#
#        % [encoding] [-] [[0]width] [{arg}] formatcode [{arg}]
#
#        encoding escapes or otherwise protects "special" characters:
#
#            "    Quoted string encoding where quote(") and
#                backslash(\) characters are \-escaped while
#                CR, LF, and TAB characters are encoded as \r,
#                \n, and \t two-character sequences.
#
#            [    Custom Squid encoding where percent(%), square
#                brackets([]), backslash(\) and characters with
#                codes outside of [32,126] range are %-encoded.
#                SP is not encoded. Used by log_mime_hdrs.
#
#            #    URL encoding (a.k.a. percent-encoding) where
#                all URL unsafe and control characters (per RFC
#                1738) are %-encoded.
#
#            /    Shell-like encoding where quote(") and
#                backslash(\) characters are \-escaped while CR
#                and LF characters are encoded as \r and \n
#                two-character sequences. Values containing SP
#                character(s) are surrounded by quotes(").
#
#            '    Raw/as-is encoding with no escaping/quoting.
#
#            Default encoding: When no explicit encoding is
#            specified, each %code determines its own encoding.
#            Most %codes use raw/as-is encoding, but some codes use
#            a so called "pass-through URL encoding" where all URL
#            unsafe and control characters (per RFC 1738) are
#            %-encoded, but the percent character(%) is left as is.
#
#        -    left aligned
#
#        width    minimum and/or maximum field width:
#                [width_min][.width_max]
#            When minimum starts with 0, the field is zero-padded.
#            String values exceeding maximum width are truncated.
#
#        {arg}    argument such as header name etc. This field may be
#            placed before or after the token, but not both at once.
#
#    Format codes:
#
#        %    a literal % character
#        sn    Unique sequence number per log line entry
#        err_code    The ID of an error response served by Squid or
#                a similar internal error identifier.
#        err_detail  Additional err_code-dependent error information.
#        note    The annotation specified by the argument. Also
#            logs the adaptation meta headers set by the
#            adaptation_meta configuration parameter.
#            If no argument given all annotations logged.
#            The argument may include a separator to use with
#            annotation values:
#                            name[:separator]
#            By default, multiple note values are separated with ","
#            and multiple notes are separated with "\r\n".
#            When logging named notes with %{name}note, the
#            explicitly configured separator is used between note
#            values. When logging all notes with %note, the
#            explicitly configured separator is used between
#            individual notes. There is currently no way to
#            specify both value and notes separators when logging
#            all notes with %note.
#        master_xaction  The master transaction identifier is an unsigned
#            integer. These IDs are guaranteed to monotonically
#            increase within a single worker process lifetime, with
#            higher values corresponding to transactions that were
#            accepted or initiated later. Due to current implementation
#            deficiencies, some IDs are skipped (i.e. never logged).
#            Concurrent workers and restarted workers use similar,
#            overlapping sequences of master transaction IDs.
#
#    Connection related format codes:
#
#        >a    Client source IP address
#        >A    Client FQDN
#        >p    Client source port
#        >eui    Client source EUI (MAC address, EUI-48 or EUI-64 identifier)
#        >la    Local IP address the client connected to
#        >lp    Local port number the client connected to
#        >qos    Client connection TOS/DSCP value set by Squid
#        >nfmark Client connection netfilter packet MARK set by Squid
#
#        la    Local listening IP address the client connection was connected to.
#        lp    Local listening port number the client connection was connected to.
#
#        <a    Server IP address of the last server or peer connection
#        <A    Server FQDN or peer name
#        <p    Server port number of the last server or peer connection
#        <la    Local IP address of the last server or peer connection
#        <lp     Local port number of the last server or peer connection
#        <qos    Server connection TOS/DSCP value set by Squid
#        <nfmark Server connection netfilter packet MARK set by Squid
#
#        >handshake Raw client handshake
#            Initial client bytes received by Squid on a newly
#            accepted TCP connection or inside a just established
#            CONNECT tunnel. Squid stops accumulating handshake
#            bytes as soon as the handshake parser succeeds or
#            fails (determining whether the client is using the
#            expected protocol).
#
#            For HTTP clients, the handshake is the request line.
#            For TLS clients, the handshake consists of all TLS
#            records up to and including the TLS record that
#            contains the last byte of the first ClientHello
#            message. For clients using an unsupported protocol,
#            this field contains the bytes received by Squid at the
#            time of the handshake parsing failure.
#
#            See the on_unsupported_protocol directive for more
#            information on Squid handshake traffic expectations.
#
#            Current support is limited to these contexts:
#            - http_port connections, but only when the
#              on_unsupported_protocol directive is in use.
#            - https_port connections (and CONNECT tunnels) that
#              are subject to the ssl_bump peek or stare action.
#
#            To protect binary handshake data, this field is always
#            base64-encoded (RFC 4648 Section 4). If logformat
#            field encoding is configured, that encoding is applied
#            on top of base64. Otherwise, the computed base64 value
#            is recorded as is.
#
#    Time related format codes:
#
#        ts    Seconds since epoch
#        tu    subsecond time (milliseconds)
#        tl    Local time. Optional strftime format argument
#                default %d/%b/%Y:%H:%M:%S %z
#        tg    GMT time. Optional strftime format argument
#                default %d/%b/%Y:%H:%M:%S %z
#        tr    Response time (milliseconds)
#        dt    Total time spent making DNS lookups (milliseconds)
#        tS    Approximate master transaction start time in
#            <full seconds since epoch>.<fractional seconds> format.
#            Currently, Squid considers the master transaction
#            started when a complete HTTP request header initiating
#            the transaction is received from the client. This is
#            the same value that Squid uses to calculate transaction
#            response time when logging %tr to access.log. Currently,
#            Squid uses millisecond resolution for %tS values,
#            similar to the default access.log "current time" field
#            (%ts.%03tu).
#
#    Access Control related format codes:
#
#        et    Tag returned by external acl
#        ea    Log string returned by external acl
#        un    User name (any available)
#        ul    User name from authentication
#        ue    User name from external acl helper
#        ui    User name from ident
#        un    A user name. Expands to the first available name
#            from the following list of information sources:
#            - authenticated user name, like %ul
#            - user name supplied by an external ACL, like %ue
#            - SSL client name, like %us
#            - ident user name, like %ui
#        credentials Client credentials. The exact meaning depends on
#            the authentication scheme: For Basic authentication,
#            it is the password; for Digest, the realm sent by the
#            client; for NTLM and Negotiate, the client challenge
#            or client credentials prefixed with "YR " or "KK ".
#
#    HTTP related format codes:
#
#        REQUEST
#
#        [http::]rm    Request method (GET/POST etc)
#        [http::]>rm    Request method from client
#        [http::]<rm    Request method sent to server or peer
#
#        [http::]ru    Request URL received (or computed) and sanitized
#
#                Logs request URI received from the client, a
#                request adaptation service, or a request
#                redirector (whichever was applied last).
#
#                Computed URLs are URIs of internally generated
#                requests and various "error:..." URIs.
#
#                Honors strip_query_terms and uri_whitespace.
#
#                This field is not encoded by default. Encoding
#                this field using variants of %-encoding will
#                clash with uri_whitespace modifications that
#                also use %-encoding.
#
#        [http::]>ru    Request URL received from the client (or computed)
#
#                Computed URLs are URIs of internally generated
#                requests and various "error:..." URIs.
#
#                Unlike %ru, this request URI is not affected
#                by request adaptation, URL rewriting services,
#                and strip_query_terms.
#
#                Honors uri_whitespace.
#
#                This field is using pass-through URL encoding
#                by default. Encoding this field using other
#                variants of %-encoding will clash with
#                uri_whitespace modifications that also use
#                %-encoding.
#
#        [http::]<ru    Request URL sent to server or peer
#        [http::]>rs    Request URL scheme from client
#        [http::]<rs    Request URL scheme sent to server or peer
#        [http::]>rd    Request URL domain from client
#        [http::]<rd    Request URL domain sent to server or peer
#        [http::]>rP    Request URL port from client
#        [http::]<rP    Request URL port sent to server or peer
#        [http::]rp    Request URL path excluding hostname
#        [http::]>rp    Request URL path excluding hostname from client
#        [http::]<rp    Request URL path excluding hostname sent to server or peer
#        [http::]rv    Request protocol version
#        [http::]>rv    Request protocol version from client
#        [http::]<rv    Request protocol version sent to server or peer
#
#        [http::]>h    Original received request header.
#                Usually differs from the request header sent by
#                Squid, although most fields are often preserved.
#                Accepts optional header field name/value filter
#                argument using name[:[separator]element] format.
#        [http::]>ha    Received request header after adaptation and
#                redirection (pre-cache REQMOD vectoring point).
#                Usually differs from the request header sent by
#                Squid, although most fields are often preserved.
#                Optional header name argument as for >h
#
#        RESPONSE
#
#        [http::]<Hs    HTTP status code received from the next hop
#        [http::]>Hs    HTTP status code sent to the client
#
#        [http::]<h    Reply header. Optional header name argument
#                as for >h
#
#        [http::]mt    MIME content type
#
#
#        SIZE COUNTERS
#
#        [http::]st    Total size of request + reply traffic with client
#        [http::]>st    Total size of request received from client.
#                Excluding chunked encoding bytes.
#        [http::]<st    Total size of reply sent to client (after adaptation)
#
#        [http::]>sh    Size of request headers received from client
#        [http::]<sh    Size of reply headers sent to client (after adaptation)
#
#        [http::]<sH    Reply high offset sent
#        [http::]<sS    Upstream object size
#
#        [http::]<bs    Number of HTTP-equivalent message body bytes
#                received from the next hop, excluding chunked
#                transfer encoding and control messages.
#                Generated FTP/Gopher listings are treated as
#                received bodies.
#
#        TIMING
#
#        [http::]<pt    Peer response time in milliseconds. The timer starts
#                when the last request byte is sent to the next hop
#                and stops when the last response byte is received.
#        [http::]<tt    Total time in milliseconds. The timer
#                starts with the first connect request (or write I/O)
#                sent to the first selected peer. The timer stops
#                with the last I/O with the last peer.
#
#    Squid handling related format codes:
#
#        Ss    Squid request status (TCP_MISS etc)
#        Sh    Squid hierarchy status (DEFAULT_PARENT etc)
#
#    SSL-related format codes:
#
#        ssl::bump_mode    SslBump decision for the transaction:
#
#                For CONNECT requests that initiated bumping of
#                a connection and for any request received on
#                an already bumped connection, Squid logs the
#                corresponding SslBump mode ("splice", "bump",
#                "peek", "stare", "terminate", "server-first"
#                or "client-first"). See the ssl_bump option
#                for more information about these modes.
#
#                A "none" token is logged for requests that
#                triggered "ssl_bump" ACL evaluation matching
#                a "none" rule.
#
#                In all other cases, a single dash ("-") is
#                logged.
#
#        ssl::>sni    SSL client SNI sent to Squid.
#
#        ssl::>cert_subject
#                The Subject field of the received client
#                SSL certificate or a dash ('-') if Squid has
#                received an invalid/malformed certificate or
#                no certificate at all. Consider encoding the
#                logged value because Subject often has spaces.
#
#        ssl::>cert_issuer
#                The Issuer field of the received client
#                SSL certificate or a dash ('-') if Squid has
#                received an invalid/malformed certificate or
#                no certificate at all. Consider encoding the
#                logged value because Issuer often has spaces.
#
#        ssl::<cert_subject
#                The Subject field of the received server
#                TLS certificate or a dash ('-') if this is
#                not available. Consider encoding the logged
#                value because Subject often has spaces.
#
#        ssl::<cert_issuer
#                The Issuer field of the received server
#                TLS certificate or a dash ('-') if this is
#                not available. Consider encoding the logged
#                value because Issuer often has spaces.
#
#        ssl::<cert
#                The received server x509 certificate in PEM
#                format, including BEGIN and END lines (or a
#                dash ('-') if the certificate is unavailable).
#
#                WARNING: Large certificates will exceed the
#                current 8KB access.log record limit, resulting
#                in truncated records. Such truncation usually
#                happens in the middle of a record field. The
#                limit applies to all access logging modules.
#
#                The logged certificate may have failed
#                validation and may not be trusted by Squid.
#                This field does not include any intermediate
#                certificates that may have been received from
#                the server or fetched during certificate
#                validation process.
#
#                Currently, Squid only collects server
#                certificates during step3 of SslBump
#                processing; connections that were not subject
#                to ssl_bump rules or that did not match a peek
#                or stare rule at step2 will not have the
#                server certificate information.
#
#                This field is using pass-through URL encoding
#                by default.
#
#        ssl::<cert_errors
#                The list of certificate validation errors
#                detected by Squid (including OpenSSL and
#                certificate validation helper components). The
#                errors are listed in the discovery order. By
#                default, the error codes are separated by ':'.
#                Accepts an optional separator argument.
#
#        %ssl::>negotiated_version The negotiated TLS version of the
#                client connection.
#
#        %ssl::<negotiated_version The negotiated TLS version of the
#                last server or peer connection.
#
#        %ssl::>received_hello_version The TLS version of the Hello
#                message received from TLS client.
#
#        %ssl::<received_hello_version The TLS version of the Hello
#                message received from TLS server.
#
#        %ssl::>received_supported_version The maximum TLS version
#                supported by the TLS client.
#
#        %ssl::<received_supported_version The maximum TLS version
#                supported by the TLS server.
#
#        %ssl::>negotiated_cipher The negotiated cipher of the
#                client connection.
#
#        %ssl::<negotiated_cipher The negotiated cipher of the
#                last server or peer connection.
#
#    If ICAP is enabled, the following code becomes available (as
#    well as ICAP log codes documented with the icap_log option):
#
#        icap::tt        Total ICAP processing time for the HTTP
#                transaction. The timer ticks when ICAP
#                ACLs are checked and when ICAP
#                transaction is in progress.
#
#    If adaptation is enabled the following codes become available:
#
#        adapt::<last_h    The header of the last ICAP response or
#                meta-information from the last eCAP
#                transaction related to the HTTP transaction.
#                Like <h, accepts an optional header name
#                argument.
#
#        adapt::sum_trs Summed adaptation transaction response
#                times recorded as a comma-separated list in
#                the order of transaction start time. Each time
#                value is recorded as an integer number,
#                representing response time of one or more
#                adaptation (ICAP or eCAP) transaction in
#                milliseconds.  When a failed transaction is
#                being retried or repeated, its time is not
#                logged individually but added to the
#                replacement (next) transaction. See also:
#                adapt::all_trs.
#
#        adapt::all_trs All adaptation transaction response times.
#                Same as adaptation_strs but response times of
#                individual transactions are never added
#                together. Instead, all transaction response
#                times are recorded individually.
#
#    You can prefix adapt::*_trs format codes with adaptation
#    service name in curly braces to record response time(s) specific
#    to that service. For example: %{my_service}adapt::sum_trs
#
#    Format codes related to the PROXY protocol:
#
#        proxy_protocol::>h PROXY protocol header, including optional TLVs.
#
#                Supports the same field and element reporting/extraction logic
#                as %http::>h. For configuration and reporting purposes, Squid
#                maps each PROXY TLV to an HTTP header field: the TLV type
#                (configured as a decimal integer) is the field name, and the
#                TLV value is the field value. All TLVs of "LOCAL" connections
#                (in PROXY protocol terminology) are currently skipped/ignored.
#
#                Squid also maps the following standard PROXY protocol header
#                blocks to pseudo HTTP headers (their names use PROXY
#                terminology and start with a colon, following HTTP tradition
#                for pseudo headers): :command, :version, :src_addr, :dst_addr,
#                :src_port, and :dst_port.
#
#                Without optional parameters, this logformat code logs
#                pseudo headers and TLVs.
#
#                This format code uses pass-through URL encoding by default.
#
#                Example:
#                    # relay custom PROXY TLV #224 to adaptation services
#                    adaptation_meta Client-Foo "%proxy_protocol::>h{224}
#
#                See also: %http::>h
#
#    The default formats available (which do not need re-defining) are:
#
#logformat squid      %ts.%03tu %6tr %>a %Ss/%03>Hs %<st %rm %ru %[un %Sh/%<a %mt
#logformat common     %>a %[ui %[un [%tl] "%rm %ru HTTP/%rv" %>Hs %<st %Ss:%Sh
#logformat combined   %>a %[ui %[un [%tl] "%rm %ru HTTP/%rv" %>Hs %<st "%{Referer}>h" "%{User-Agent}>h" %Ss:%Sh
#logformat referrer   %ts.%03tu %>a %{Referer}>h %ru
#logformat useragent  %>a [%tl] "%{User-Agent}>h"
#
#    NOTE: When the log_mime_hdrs directive is set to ON.
#        The squid, common and combined formats have a safely encoded copy
#        of the mime headers appended to each line within a pair of brackets.
#
#    NOTE: The common and combined formats are not quite true to the Apache definition.
#        The logs from Squid contain an extra status and hierarchy code appended.
#
#Default:
# The format definitions squid, common, combined, referrer, useragent are built in.

#  TAG: access_log
#    Configures whether and how Squid logs HTTP and ICP transactions.
#    If access logging is enabled, a single line is logged for every
#    matching HTTP or ICP request. The recommended directive formats are:
#
#    access_log <module>:<place> [option ...] [acl acl ...]
#    access_log none [acl acl ...]
#
#    The following directive format is accepted but may be deprecated:
#    access_log <module>:<place> [<logformat name> [acl acl ...]]
#
#        In most cases, the first ACL name must not contain the '=' character
#    and should not be equal to an existing logformat name. You can always
#    start with an 'all' ACL to work around those restrictions.
#
#    Will log to the specified module:place using the specified format (which
#    must be defined in a logformat directive) those entries which match
#    ALL the acl's specified (which must be defined in acl clauses).
#    If no acl is specified, all requests will be logged to this destination.
#
#    ===== Available options for the recommended directive format =====
#
#    logformat=name        Names log line format (either built-in or
#                defined by a logformat directive). Defaults
#                to 'squid'.
#
#    buffer-size=64KB    Defines approximate buffering limit for log
#                records (see buffered_logs).  Squid should not
#                keep more than the specified size and, hence,
#                should flush records before the buffer becomes
#                full to avoid overflows under normal
#                conditions (the exact flushing algorithm is
#                module-dependent though).  The on-error option
#                controls overflow handling.
#
#    on-error=die|drop    Defines action on unrecoverable errors. The
#                'drop' action ignores (i.e., does not log)
#                affected log records. The default 'die' action
#                kills the affected worker. The drop action
#                support has not been tested for modules other
#                than tcp.
#
#    rotate=N        Specifies the number of log file rotations to
#                make when you run 'squid -k rotate'. The default
#                is to obey the logfile_rotate directive. Setting
#                rotate=0 will disable the file name rotation,
#                but the log files are still closed and re-opened.
#                This will enable you to rename the logfiles
#                yourself just before sending the rotate signal.
#                Only supported by the stdio module.
#
#    ===== Modules Currently available =====
#
#    none    Do not log any requests matching these ACL.
#        Do not specify Place or logformat name.
#
#    stdio    Write each log line to disk immediately at the completion of
#        each request.
#        Place: the filename and path to be written.
#
#    daemon    Very similar to stdio. But instead of writing to disk the log
#        line is passed to a daemon helper for asychronous handling instead.
#        Place: varies depending on the daemon.
#
#        log_file_daemon Place: the file name and path to be written.
#
#    syslog    To log each request via syslog facility.
#        Place: The syslog facility and priority level for these entries.
#        Place Format:  facility.priority
#
#        where facility could be any of:
#            authpriv, daemon, local0 ... local7 or user.
#
#        And priority could be any of:
#            err, warning, notice, info, debug.
#
#    udp    To send each log line as text data to a UDP receiver.
#        Place: The destination host name or IP and port.
#        Place Format:   //host:port
#
#    tcp    To send each log line as text data to a TCP receiver.
#        Lines may be accumulated before sending (see buffered_logs).
#        Place: The destination host name or IP and port.
#        Place Format:   //host:port
#
#    Default:
#        access_log daemon:/var/log/squid/access.log squid
#Default:
# access_log daemon:/var/log/squid/access.log squid

#  TAG: icap_log
#    ICAP log files record ICAP transaction summaries, one line per
#    transaction.
#
#    The icap_log option format is:
#    icap_log <filepath> [<logformat name> [acl acl ...]]
#    icap_log none [acl acl ...]]
#
#    Please see access_log option documentation for details. The two
#    kinds of logs share the overall configuration approach and many
#    features.
#
#    ICAP processing of a single HTTP message or transaction may
#    require multiple ICAP transactions.  In such cases, multiple
#    ICAP transaction log lines will correspond to a single access
#    log line.
#
#    ICAP log supports many access.log logformat %codes. In ICAP context,
#    HTTP message-related %codes are applied to the HTTP message embedded
#    in an ICAP message. Logformat "%http::>..." codes are used for HTTP
#    messages embedded in ICAP requests while "%http::<..." codes are used
#    for HTTP messages embedded in ICAP responses. For example:
#
#        http::>h    To-be-adapted HTTP message headers sent by Squid to
#                the ICAP service. For REQMOD transactions, these are
#                HTTP request headers. For RESPMOD, these are HTTP
#                response headers, but Squid currently cannot log them
#                (i.e., %http::>h will expand to "-" for RESPMOD).
#
#        http::<h    Adapted HTTP message headers sent by the ICAP
#                service to Squid (i.e., HTTP request headers in regular
#                REQMOD; HTTP response headers in RESPMOD and during
#                request satisfaction in REQMOD).
#
#    ICAP OPTIONS transactions do not embed HTTP messages.
#
#    Several logformat codes below deal with ICAP message bodies. An ICAP
#    message body, if any, typically includes a complete HTTP message
#    (required HTTP headers plus optional HTTP message body). When
#    computing HTTP message body size for these logformat codes, Squid
#    either includes or excludes chunked encoding overheads; see
#    code-specific documentation for details.
#
#    For Secure ICAP services, all size-related information is currently
#    computed before/after TLS encryption/decryption, as if TLS was not
#    in use at all.
#
#    The following format codes are also available for ICAP logs:
#
#        icap::<A    ICAP server IP address. Similar to <A.
#
#        icap::<service_name    ICAP service name from the icap_service
#                option in Squid configuration file.
#
#        icap::ru    ICAP Request-URI. Similar to ru.
#
#        icap::rm    ICAP request method (REQMOD, RESPMOD, or
#                OPTIONS). Similar to existing rm.
#
#        icap::>st    The total size of the ICAP request sent to the ICAP
#                server (ICAP headers + ICAP body), including chunking
#                metadata (if any).
#
#        icap::<st    The total size of the ICAP response received from the
#                ICAP server (ICAP headers + ICAP body), including
#                chunking metadata (if any).
#
#        icap::<bs    The size of the ICAP response body received from the
#                ICAP server, excluding chunking metadata (if any).
#
#        icap::tr     Transaction response time (in
#                milliseconds).  The timer starts when
#                the ICAP transaction is created and
#                stops when the transaction is completed.
#                Similar to tr.
#
#        icap::tio    Transaction I/O time (in milliseconds). The
#                timer starts when the first ICAP request
#                byte is scheduled for sending. The timers
#                stops when the last byte of the ICAP response
#                is received.
#
#        icap::to     Transaction outcome: ICAP_ERR* for all
#                transaction errors, ICAP_OPT for OPTION
#                transactions, ICAP_ECHO for 204
#                responses, ICAP_MOD for message
#                modification, and ICAP_SAT for request
#                satisfaction. Similar to Ss.
#
#        icap::Hs    ICAP response status code. Similar to Hs.
#
#        icap::>h    ICAP request header(s). Similar to >h.
#
#        icap::<h    ICAP response header(s). Similar to <h.
#
#    The default ICAP log format, which can be used without an explicit
#    definition, is called icap_squid:
#
#logformat icap_squid %ts.%03tu %6icap::tr %>A %icap::to/%03icap::Hs %icap::<st %icap::rm %icap::ru %un -/%icap::<A -
#
#    See also: logformat and %adapt::<last_h
#Default:
# none

#  TAG: logfile_daemon
#    Specify the path to the logfile-writing daemon. This daemon is
#    used to write the access and store logs, if configured.
#
#    Squid sends a number of commands to the log daemon:
#      L<data>\n - logfile data
#      R\n - rotate file
#      T\n - truncate file
#      O\n - reopen file
#      F\n - flush file
#      r<n>\n - set rotate count to <n>
#      b<n>\n - 1 = buffer output, 0 = don't buffer output
#
#    No responses is expected.
#Default:
# logfile_daemon /usr/lib/squid/log_file_daemon

#  TAG: stats_collection    allow|deny acl acl...
#    This options allows you to control which requests gets accounted
#    in performance counters.
#
#    This clause only supports fast acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#Default:
# Allow logging for all transactions.

#  TAG: cache_store_log
#    Logs the activities of the storage manager.  Shows which
#    objects are ejected from the cache, and which objects are
#    saved and for how long.
#    There are not really utilities to analyze this data, so you can safely
#    disable it (the default).
#
#    Store log uses modular logging outputs. See access_log for the list
#    of modules supported.
#
#    Example:
#        cache_store_log stdio:/var/log/squid/store.log
#        cache_store_log daemon:/var/log/squid/store.log
#Default:
# none

#  TAG: cache_swap_state
#    Location for the cache "swap.state" file. This index file holds
#    the metadata of objects saved on disk.  It is used to rebuild
#    the cache during startup.  Normally this file resides in each
#    'cache_dir' directory, but you may specify an alternate
#    pathname here.  Note you must give a full filename, not just
#    a directory. Since this is the index for the whole object
#    list you CANNOT periodically rotate it!
#
#    If %s can be used in the file name it will be replaced with a
#    a representation of the cache_dir name where each / is replaced
#    with '.'. This is needed to allow adding/removing cache_dir
#    lines when cache_swap_log is being used.
#
#    If have more than one 'cache_dir', and %s is not used in the name
#    these swap logs will have names such as:
#
#        cache_swap_log.00
#        cache_swap_log.01
#        cache_swap_log.02
#
#    The numbered extension (which is added automatically)
#    corresponds to the order of the 'cache_dir' lines in this
#    configuration file.  If you change the order of the 'cache_dir'
#    lines in this file, these index files will NOT correspond to
#    the correct 'cache_dir' entry (unless you manually rename
#    them).  We recommend you do NOT use this option.  It is
#    better to keep these index files in each 'cache_dir' directory.
#Default:
# Store the journal inside its cache_dir

#  TAG: logfile_rotate
#    Specifies the default number of logfile rotations to make when you
#    type 'squid -k rotate'. The default is 10, which will rotate
#    with extensions 0 through 9. Setting logfile_rotate to 0 will
#    disable the file name rotation, but the logfiles are still closed
#    and re-opened. This will enable you to rename the logfiles
#    yourself just before sending the rotate signal.
#
#    Note, from Squid-3.1 this option is only a default for cache.log,
#    that log can be rotated separately by using debug_options.
#
#    Note, from Squid-4 this option is only a default for access.log
#    recorded by stdio: module. Those logs can be rotated separately by
#    using the rotate=N option on their access_log directive.
#
#    Note, the 'squid -k rotate' command normally sends a USR1
#    signal to the running squid process.  In certain situations
#    (e.g. on Linux with Async I/O), USR1 is used for other
#    purposes, so -k rotate uses another signal.  It is best to get
#    in the habit of using 'squid -k rotate' instead of 'kill -USR1
#    <pid>'.
#
#    Note, for Debian/Linux the default of logfile_rotate is
#    zero, since it includes external logfile-rotation methods.
#Default:
# logfile_rotate 0

#  TAG: mime_table
#    Path to Squid's icon configuration file.
#
#    You shouldn't need to change this, but the default file contains
#    examples and formatting information if you do.
#Default:
# mime_table /usr/share/squid/mime.conf

#  TAG: log_mime_hdrs    on|off
#    The Cache can record both the request and the response MIME
#    headers for each HTTP transaction.  The headers are encoded
#    safely and will appear as two bracketed fields at the end of
#    the access log (for either the native or httpd-emulated log
#    formats).  To enable this logging set log_mime_hdrs to 'on'.
#Default:
# log_mime_hdrs off

#  TAG: pid_filename
#    A filename to write the process-id to.  To disable, enter "none".
#Default:
# pid_filename /run/squid.pid

#  TAG: client_netmask
#    A netmask for client addresses in logfiles and cachemgr output.
#    Change this to protect the privacy of your cache clients.
#    A netmask of 255.255.255.0 will log all IP's in that range with
#    the last digit set to '0'.
#Default:
# Log full client IP address

#  TAG: strip_query_terms
#    By default, Squid strips query terms from requested URLs before
#    logging.  This protects your user's privacy and reduces log size.
#
#    When investigating HIT/MISS or other caching behaviour you
#    will need to disable this to see the full URL used by Squid.
#Default:
# strip_query_terms on

#  TAG: buffered_logs    on|off
#    Whether to write/send access_log records ASAP or accumulate them and
#    then write/send them in larger chunks. Buffering may improve
#    performance because it decreases the number of I/Os. However,
#    buffering increases the delay before log records become available to
#    the final recipient (e.g., a disk file or logging daemon) and,
#    hence, increases the risk of log records loss.
#
#    Note that even when buffered_logs are off, Squid may have to buffer
#    records if it cannot write/send them immediately due to pending I/Os
#    (e.g., the I/O writing the previous log record) or connectivity loss.
#
#    Currently honored by 'daemon' and 'tcp' access_log modules only.
#Default:
# buffered_logs off

#  TAG: netdb_filename
#    Where Squid stores it's netdb journal.
#    When enabled this journal preserves netdb state between restarts.
#
#    To disable, enter "none".
#Default:
# netdb_filename stdio:/var/spool/squid/netdb.state

# OPTIONS FOR TROUBLESHOOTING
# -----------------------------------------------------------------------------

#  TAG: cache_log
#    Squid administrative logging file.
#
#    This is where general information about Squid behavior goes. You can
#    increase the amount of data logged to this file and how often it is
#    rotated with "debug_options"
#Default:
# cache_log /var/log/squid/cache.log

#  TAG: debug_options
#    Logging options are set as section,level where each source file
#    is assigned a unique section.  Lower levels result in less
#    output,  Full debugging (level 9) can result in a very large
#    log file, so be careful.
#
#    The magic word "ALL" sets debugging levels for all sections.
#    The default is to run with "ALL,1" to record important warnings.
#
#    The rotate=N option can be used to keep more or less of these logs
#    than would otherwise be kept by logfile_rotate.
#    For most uses a single log should be enough to monitor current
#    events affecting Squid.
#Default:
# Log all critical and important messages.

#  TAG: coredump_dir
#    By default Squid leaves core files in the directory from where
#    it was started. If you set 'coredump_dir' to a directory
#    that exists, Squid will chdir() to that directory at startup
#    and coredump files will be left there.
#
#Default:
# Use the directory from where Squid was started.
#

# Leave coredumps in the first cache dir
coredump_dir /var/spool/squid

# OPTIONS FOR FTP GATEWAYING
# -----------------------------------------------------------------------------

#  TAG: ftp_user
#    If you want the anonymous login password to be more informative
#    (and enable the use of picky FTP servers), set this to something
#    reasonable for your domain, like wwwuser@somewhere.net
#
#    The reason why this is domainless by default is the
#    request can be made on the behalf of a user in any domain,
#    depending on how the cache is used.
#    Some FTP server also validate the email address is valid
#    (for example perl.com).
#Default:
# ftp_user Squid@

#  TAG: ftp_passive
#    If your firewall does not allow Squid to use passive
#    connections, turn off this option.
#
#    Use of ftp_epsv_all option requires this to be ON.
#Default:
# ftp_passive on

#  TAG: ftp_epsv_all
#    FTP Protocol extensions permit the use of a special "EPSV ALL" command.
#
#    NATs may be able to put the connection on a "fast path" through the
#    translator, as the EPRT command will never be used and therefore,
#    translation of the data portion of the segments will never be needed.
#
#    When a client only expects to do two-way FTP transfers this may be
#    useful.
#    If squid finds that it must do a three-way FTP transfer after issuing
#    an EPSV ALL command, the FTP session will fail.
#
#    If you have any doubts about this option do not use it.
#    Squid will nicely attempt all other connection methods.
#
#    Requires ftp_passive to be ON (default) for any effect.
#Default:
# ftp_epsv_all off

#  TAG: ftp_epsv
#    FTP Protocol extensions permit the use of a special "EPSV" command.
#
#    NATs may be able to put the connection on a "fast path" through the
#    translator using EPSV, as the EPRT command will never be used
#    and therefore, translation of the data portion of the segments
#    will never be needed.
#
#    EPSV is often required to interoperate with FTP servers on IPv6
#    networks. On the other hand, it may break some IPv4 servers.
#
#    By default, EPSV may try EPSV with any FTP server. To fine tune
#    that decision, you may restrict EPSV to certain clients or servers
#    using ACLs:
#
#        ftp_epsv allow|deny al1 acl2 ...
#
#    WARNING: Disabling EPSV may cause problems with external NAT and IPv6.
#
#    Only fast ACLs are supported.
#    Requires ftp_passive to be ON (default) for any effect.
#Default:
# none

#  TAG: ftp_eprt
#    FTP Protocol extensions permit the use of a special "EPRT" command.
#
#    This extension provides a protocol neutral alternative to the
#    IPv4-only PORT command. When supported it enables active FTP data
#    channels over IPv6 and efficient NAT handling.
#
#    Turning this OFF will prevent EPRT being attempted and will skip
#    straight to using PORT for IPv4 servers.
#
#    Some devices are known to not handle this extension correctly and
#    may result in crashes. Devices which suport EPRT enough to fail
#    cleanly will result in Squid attempting PORT anyway. This directive
#    should only be disabled when EPRT results in device failures.
#
#    WARNING: Doing so will convert Squid back to the old behavior with all
#    the related problems with external NAT devices/layers and IPv4-only FTP.
#Default:
# ftp_eprt on

#  TAG: ftp_sanitycheck
#    For security and data integrity reasons Squid by default performs
#    sanity checks of the addresses of FTP data connections ensure the
#    data connection is to the requested server. If you need to allow
#    FTP connections to servers using another IP address for the data
#    connection turn this off.
#Default:
# ftp_sanitycheck on

#  TAG: ftp_telnet_protocol
#    The FTP protocol is officially defined to use the telnet protocol
#    as transport channel for the control connection. However, many
#    implementations are broken and does not respect this aspect of
#    the FTP protocol.
#
#    If you have trouble accessing files with ASCII code 255 in the
#    path or similar problems involving this ASCII code you can
#    try setting this directive to off. If that helps, report to the
#    operator of the FTP server in question that their FTP server
#    is broken and does not follow the FTP standard.
#Default:
# ftp_telnet_protocol on

# OPTIONS FOR EXTERNAL SUPPORT PROGRAMS
# -----------------------------------------------------------------------------

#  TAG: diskd_program
#    Specify the location of the diskd executable.
#    Note this is only useful if you have compiled in
#    diskd as one of the store io modules.
#Default:
# diskd_program /usr/lib/squid/diskd

#  TAG: unlinkd_program
#    Specify the location of the executable for file deletion process.
#Default:
# unlinkd_program /usr/lib/squid/unlinkd

#  TAG: pinger_program
#    Specify the location of the executable for the pinger process.
#Default:
# pinger_program /usr/lib/squid/pinger

#  TAG: pinger_enable
#    Control whether the pinger is active at run-time.
#    Enables turning ICMP pinger on and off with a simple
#    squid -k reconfigure.
#Default:
# pinger_enable on

# OPTIONS FOR URL REWRITING
# -----------------------------------------------------------------------------

#  TAG: url_rewrite_program
#    The name and command line parameters of an admin-provided executable
#    for redirecting clients or adjusting/replacing client request URLs.
#
#    This helper is consulted after the received request is cleared by
#    http_access and adapted using eICAP/ICAP services (if any). If the
#    helper does not redirect the client, Squid checks adapted_http_access
#    and may consult the cache or forward the request to the next hop.
#
#
#    For each request, the helper gets one line in the following format:
#
#      [channel-ID <SP>] request-URL [<SP> extras] <NL>
#
#    Use url_rewrite_extras to configure what Squid sends as 'extras'.
#
#
#    The helper must reply to each query using a single line:
#
#      [channel-ID <SP>] result [<SP> kv-pairs] <NL>
#
#    The result section must match exactly one of the following outcomes:
#
#      OK [status=30N] url="..."
#
#        Redirect the client to a URL supplied in the 'url' parameter.
#        Optional 'status' specifies the status code to send to the
#        client in Squid's HTTP redirect response. It must be one of
#        the standard HTTP redirect status codes: 301, 302, 303, 307,
#        or 308. When no specific status is requested, Squid uses 302.
#
#      OK rewrite-url="..."
#
#        Replace the current request URL with the one supplied in the
#        'rewrite-url' parameter. Squid fetches the resource specified
#        by the new URL and forwards the received response (or its
#        cached copy) to the client.
#
#        WARNING: Avoid rewriting URLs! When possible, redirect the
#        client using an "OK url=..." helper response instead.
#        Rewriting URLs may create inconsistent requests and/or break
#        synchronization between internal client and origin server
#        states, especially when URLs or other message parts contain
#        snippets of that state. For example, Squid does not adjust
#        Location headers and embedded URLs after the helper rewrites
#        the request URL.
#
#      OK
#        Keep the client request intact.
#
#      ERR
#        Keep the client request intact.
#
#      BH [message="..."]
#        A helper problem that should be reported to the Squid admin
#        via a level-1 cache.log message. The 'message' parameter is
#        reserved for specifying the log message.
#
#    In addition to the kv-pairs mentioned above, Squid also understands
#    the following optional kv-pairs in URL rewriter responses:
#
#      clt_conn_tag=TAG
#        Associates a TAG with the client TCP connection.
#
#        The clt_conn_tag=TAG pair is treated as a regular transaction
#        annotation for the current request and also annotates future
#        requests on the same client connection. A helper may update
#        the TAG during subsequent requests by returning a new kv-pair.
#
#
#    Helper messages contain the channel-ID part if and only if the
#    url_rewrite_children directive specifies positive concurrency. As a
#    channel-ID value, Squid sends a number between 0 and concurrency-1.
#    The helper must echo back the received channel-ID in its response.
#
#    By default, Squid does not use a URL rewriter.
#Default:
# none

#  TAG: url_rewrite_children
#    Specifies the maximum number of redirector processes that Squid may
#    spawn (numberofchildren) and several related options. Using too few of
#    these helper processes (a.k.a. "helpers") creates request queues.
#    Using too many helpers wastes your system resources.
#
#    Usage: numberofchildren [option]...
#
#    The startup= and idle= options allow some measure of skew in your
#    tuning.
#
#        startup=
#
#    Sets a minimum of how many processes are to be spawned when Squid
#    starts or reconfigures. When set to zero the first request will
#    cause spawning of the first child process to handle it.
#
#    Starting too few will cause an initial slowdown in traffic as Squid
#    attempts to simultaneously spawn enough processes to cope.
#
#        idle=
#
#    Sets a minimum of how many processes Squid is to try and keep available
#    at all times. When traffic begins to rise above what the existing
#    processes can handle this many more will be spawned up to the maximum
#    configured. A minimum setting of 1 is required.
#
#        concurrency=
#
#    The number of requests each redirector helper can handle in
#    parallel. Defaults to 0 which indicates the redirector
#    is a old-style single threaded redirector.
#
#    When this directive is set to a value >= 1 then the protocol
#    used to communicate with the helper is modified to include
#    an ID in front of the request/response. The ID from the request
#    must be echoed back with the response to that request.
#
#        queue-size=N
#
#    Sets the maximum number of queued requests. A request is queued when
#    no existing child can accept it due to concurrency limit and no new
#    child can be started due to numberofchildren limit. The default
#    maximum is zero if url_rewrite_bypass is enabled and
#    2*numberofchildren otherwise. If the queued requests exceed queue size
#    and redirector_bypass configuration option is set, then redirector is
#    bypassed. Otherwise, Squid is allowed to temporarily exceed the
#    configured maximum, marking the affected helper as "overloaded". If
#    the helper overload lasts more than 3 minutes, the action prescribed
#    by the on-persistent-overload option applies.
#
#        on-persistent-overload=action
#
#    Specifies Squid reaction to a new helper request arriving when the helper
#    has been overloaded for more that 3 minutes already. The number of queued
#    requests determines whether the helper is overloaded (see the queue-size
#    option).
#
#    Two actions are supported:
#
#      die    Squid worker quits. This is the default behavior.
#
#      ERR    Squid treats the helper request as if it was
#        immediately submitted, and the helper immediately
#        replied with an ERR response. This action has no effect
#        on the already queued and in-progress helper requests.
#Default:
# url_rewrite_children 20 startup=0 idle=1 concurrency=0

#  TAG: url_rewrite_host_header
#    To preserve same-origin security policies in browsers and
#    prevent Host: header forgery by redirectors Squid rewrites
#    any Host: header in redirected requests.
#
#    If you are running an accelerator this may not be a wanted
#    effect of a redirector. This directive enables you disable
#    Host: alteration in reverse-proxy traffic.
#
#    WARNING: Entries are cached on the result of the URL rewriting
#    process, so be careful if you have domain-virtual hosts.
#
#    WARNING: Squid and other software verifies the URL and Host
#    are matching, so be careful not to relay through other proxies
#    or inspecting firewalls with this disabled.
#Default:
# url_rewrite_host_header on

#  TAG: url_rewrite_access
#    If defined, this access list specifies which requests are
#    sent to the redirector processes.
#
#    This clause supports both fast and slow acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#Default:
# Allow, unless rules exist in squid.conf.

#  TAG: url_rewrite_bypass
#    When this is 'on', a request will not go through the
#    redirector if all the helpers are busy. If this is 'off' and the
#    redirector queue grows too large, the action is prescribed by the
#    on-persistent-overload option. You should only enable this if the
#    redirectors are not critical to your caching system. If you use
#    redirectors for access control, and you enable this option,
#    users may have access to pages they should not
#    be allowed to request.
#
#    Enabling this option sets the default url_rewrite_children queue-size
#    option value to 0.
#Default:
# url_rewrite_bypass off

#  TAG: url_rewrite_extras
#    Specifies a string to be append to request line format for the
#    rewriter helper. "Quoted" format values may contain spaces and
#    logformat %macros. In theory, any logformat %macro can be used.
#    In practice, a %macro expands as a dash (-) if the helper request is
#    sent before the required macro information is available to Squid.
#Default:
# url_rewrite_extras "%>a/%>A %un %>rm myip=%la myport=%lp"

#  TAG: url_rewrite_timeout
#    Squid times active requests to redirector. The timeout value and Squid
#    reaction to a timed out request are configurable using the following
#    format:
#
#    url_rewrite_timeout timeout time-units on_timeout=<action> [response=<quoted-response>]
#
#    supported timeout actions:
#        fail    Squid return a ERR_GATEWAY_FAILURE error page
#
#        bypass    Do not re-write the URL
#
#        retry    Send the lookup to the helper again
#
#        use_configured_response
#            Use the <quoted-response> as helper response
#Default:
# Squid waits for the helper response forever

# OPTIONS FOR STORE ID
# -----------------------------------------------------------------------------

#  TAG: store_id_program
#    Specify the location of the executable StoreID helper to use.
#    Since they can perform almost any function there isn't one included.
#
#    For each requested URL, the helper will receive one line with the format
#
#      [channel-ID <SP>] URL [<SP> extras]<NL>
#
#
#    After processing the request the helper must reply using the following format:
#
#      [channel-ID <SP>] result [<SP> kv-pairs]
#
#    The result code can be:
#
#      OK store-id="..."
#        Use the StoreID supplied in 'store-id='.
#
#      ERR
#        The default is to use HTTP request URL as the store ID.
#
#      BH
#        An internal error occurred in the helper, preventing
#        a result being identified.
#
#    In addition to the above kv-pairs Squid also understands the following
#    optional kv-pairs received from URL rewriters:
#      clt_conn_tag=TAG
#        Associates a TAG with the client TCP connection.
#        Please see url_rewrite_program related documentation for this
#        kv-pair
#
#    Helper programs should be prepared to receive and possibly ignore
#    additional whitespace-separated tokens on each input line.
#
#    When using the concurrency= option the protocol is changed by
#    introducing a query channel tag in front of the request/response.
#    The query channel tag is a number between 0 and concurrency-1.
#    This value must be echoed back unchanged to Squid as the first part
#    of the response relating to its request.
#
#    NOTE: when using StoreID refresh_pattern will apply to the StoreID
#          returned from the helper and not the URL.
#
#    WARNING: Wrong StoreID value returned by a careless helper may result
#             in the wrong cached response returned to the user.
#
#    By default, a StoreID helper is not used.
#Default:
# none

#  TAG: store_id_extras
#        Specifies a string to be append to request line format for the
#        StoreId helper. "Quoted" format values may contain spaces and
#        logformat %macros. In theory, any logformat %macro can be used.
#        In practice, a %macro expands as a dash (-) if the helper request is
#        sent before the required macro information is available to Squid.
#Default:
# store_id_extras "%>a/%>A %un %>rm myip=%la myport=%lp"

#  TAG: store_id_children
#    Specifies the maximum number of StoreID helper processes that Squid
#    may spawn (numberofchildren) and several related options. Using
#    too few of these helper processes (a.k.a. "helpers") creates request
#    queues. Using too many helpers wastes your system resources.
#
#    Usage: numberofchildren [option]...
#
#    The startup= and idle= options allow some measure of skew in your
#    tuning.
#
#        startup=
#
#    Sets a minimum of how many processes are to be spawned when Squid
#    starts or reconfigures. When set to zero the first request will
#    cause spawning of the first child process to handle it.
#
#    Starting too few will cause an initial slowdown in traffic as Squid
#    attempts to simultaneously spawn enough processes to cope.
#
#        idle=
#
#    Sets a minimum of how many processes Squid is to try and keep available
#    at all times. When traffic begins to rise above what the existing
#    processes can handle this many more will be spawned up to the maximum
#    configured. A minimum setting of 1 is required.
#
#        concurrency=
#
#    The number of requests each storeID helper can handle in
#    parallel. Defaults to 0 which indicates the helper
#    is a old-style single threaded program.
#
#    When this directive is set to a value >= 1 then the protocol
#    used to communicate with the helper is modified to include
#    an ID in front of the request/response. The ID from the request
#    must be echoed back with the response to that request.
#
#        queue-size=N
#
#    Sets the maximum number of queued requests to N. A request is queued
#    when no existing child can accept it due to concurrency limit and no
#    new child can be started due to numberofchildren limit. The default
#    maximum is 2*numberofchildren. If the queued requests exceed queue
#    size and redirector_bypass configuration option is set, then
#    redirector is bypassed. Otherwise, Squid is allowed to temporarily
#    exceed the configured maximum, marking the affected helper as
#    "overloaded". If the helper overload lasts more than 3 minutes, the
#    action prescribed by the on-persistent-overload option applies.
#
#        on-persistent-overload=action
#
#    Specifies Squid reaction to a new helper request arriving when the helper
#    has been overloaded for more that 3 minutes already. The number of queued
#    requests determines whether the helper is overloaded (see the queue-size
#    option).
#
#    Two actions are supported:
#
#      die    Squid worker quits. This is the default behavior.
#
#      ERR    Squid treats the helper request as if it was
#        immediately submitted, and the helper immediately
#        replied with an ERR response. This action has no effect
#        on the already queued and in-progress helper requests.
#Default:
# store_id_children 20 startup=0 idle=1 concurrency=0

#  TAG: store_id_access
#    If defined, this access list specifies which requests are
#    sent to the StoreID processes.  By default all requests
#    are sent.
#
#    This clause supports both fast and slow acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#Default:
# Allow, unless rules exist in squid.conf.

#  TAG: store_id_bypass
#    When this is 'on', a request will not go through the
#    helper if all helpers are busy. If this is 'off' and the helper
#    queue grows too large, the action is prescribed by the
#    on-persistent-overload option. You should only enable this if the
#    helpers are not critical to your caching system. If you use
#    helpers for critical caching components, and you enable this
#    option,    users may not get objects from cache.
#    This options sets default queue-size option of the store_id_children
#    to 0.
#Default:
# store_id_bypass on

# OPTIONS FOR TUNING THE CACHE
# -----------------------------------------------------------------------------

#  TAG: cache
#    Requests denied by this directive will not be served from the cache
#    and their responses will not be stored in the cache. This directive
#    has no effect on other transactions and on already cached responses.
#
#    This clause supports both fast and slow acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#
#    This and the two other similar caching directives listed below are
#    checked at different transaction processing stages, have different
#    access to response information, affect different cache operations,
#    and differ in slow ACLs support:
#
#    * cache: Checked before Squid makes a hit/miss determination.
#        No access to reply information!
#        Denies both serving a hit and storing a miss.
#        Supports both fast and slow ACLs.
#    * send_hit: Checked after a hit was detected.
#        Has access to reply (hit) information.
#        Denies serving a hit only.
#        Supports fast ACLs only.
#    * store_miss: Checked before storing a cachable miss.
#        Has access to reply (miss) information.
#        Denies storing a miss only.
#        Supports fast ACLs only.
#
#    If you are not sure which of the three directives to use, apply the
#    following decision logic:
#
#    * If your ACL(s) are of slow type _and_ need response info, redesign.
#      Squid does not support that particular combination at this time.
#        Otherwise:
#    * If your directive ACL(s) are of slow type, use "cache"; and/or
#    * if your directive ACL(s) need no response info, use "cache".
#        Otherwise:
#    * If you do not want the response cached, use store_miss; and/or
#    * if you do not want a hit on a cached response, use send_hit.
#Default:
# By default, this directive is unused and has no effect.

#  TAG: send_hit
#    Responses denied by this directive will not be served from the cache
#    (but may still be cached, see store_miss). This directive has no
#    effect on the responses it allows and on the cached objects.
#
#    Please see the "cache" directive for a summary of differences among
#    store_miss, send_hit, and cache directives.
#
#    Unlike the "cache" directive, send_hit only supports fast acl
#    types.  See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#
#    For example:
#
#        # apply custom Store ID mapping to some URLs
#        acl MapMe dstdomain .c.example.com
#        store_id_program ...
#        store_id_access allow MapMe
#
#        # but prevent caching of special responses
#        # such as 302 redirects that cause StoreID loops
#        acl Ordinary http_status 200-299
#        store_miss deny MapMe !Ordinary
#
#        # and do not serve any previously stored special responses
#        # from the cache (in case they were already cached before
#        # the above store_miss rule was in effect).
#        send_hit deny MapMe !Ordinary
#Default:
# By default, this directive is unused and has no effect.

#  TAG: store_miss
#    Responses denied by this directive will not be cached (but may still
#    be served from the cache, see send_hit). This directive has no
#    effect on the responses it allows and on the already cached responses.
#
#    Please see the "cache" directive for a summary of differences among
#    store_miss, send_hit, and cache directives. See the
#    send_hit directive for a usage example.
#
#    Unlike the "cache" directive, store_miss only supports fast acl
#    types.  See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#Default:
# By default, this directive is unused and has no effect.

#  TAG: max_stale    time-units
#    This option puts an upper limit on how stale content Squid
#    will serve from the cache if cache validation fails.
#    Can be overriden by the refresh_pattern max-stale option.
#Default:
# max_stale 1 week

#  TAG: refresh_pattern
#    usage: refresh_pattern [-i] regex min percent max [options]
#
#    By default, regular expressions are CASE-SENSITIVE.  To make
#    them case-insensitive, use the -i option.
#
#    'Min' is the time (in minutes) an object without an explicit
#    expiry time should be considered fresh. The recommended
#    value is 0, any higher values may cause dynamic applications
#    to be erroneously cached unless the application designer
#    has taken the appropriate actions.
#
#    'Percent' is a percentage of the objects age (time since last
#    modification age) an object without explicit expiry time
#    will be considered fresh.
#
#    'Max' is an upper limit on how long objects without an explicit
#    expiry time will be considered fresh. The value is also used
#    to form Cache-Control: max-age header for a request sent from
#    Squid to origin/parent.
#
#    options: override-expire
#         override-lastmod
#         reload-into-ims
#         ignore-reload
#         ignore-no-store
#         ignore-private
#         max-stale=NN
#         refresh-ims
#         store-stale
#
#        override-expire enforces min age even if the server
#        sent an explicit expiry time (e.g., with the
#        Expires: header or Cache-Control: max-age). Doing this
#        VIOLATES the HTTP standard.  Enabling this feature
#        could make you liable for problems which it causes.
#
#        Note: override-expire does not enforce staleness - it only extends
#        freshness / min. If the server returns a Expires time which
#        is longer than your max time, Squid will still consider
#        the object fresh for that period of time.
#
#        override-lastmod enforces min age even on objects
#        that were modified recently.
#
#        reload-into-ims changes a client no-cache or ``reload''
#        request for a cached entry into a conditional request using
#        If-Modified-Since and/or If-None-Match headers, provided the
#        cached entry has a Last-Modified and/or a strong ETag header.
#        Doing this VIOLATES the HTTP standard. Enabling this feature
#        could make you liable for problems which it causes.
#
#        ignore-reload ignores a client no-cache or ``reload''
#        header. Doing this VIOLATES the HTTP standard. Enabling
#        this feature could make you liable for problems which
#        it causes.
#
#        ignore-no-store ignores any ``Cache-control: no-store''
#        headers received from a server. Doing this VIOLATES
#        the HTTP standard. Enabling this feature could make you
#        liable for problems which it causes.
#
#        ignore-private ignores any ``Cache-control: private''
#        headers received from a server. Doing this VIOLATES
#        the HTTP standard. Enabling this feature could make you
#        liable for problems which it causes.
#
#        refresh-ims causes squid to contact the origin server
#        when a client issues an If-Modified-Since request. This
#        ensures that the client will receive an updated version
#        if one is available.
#
#        store-stale stores responses even if they don't have explicit
#        freshness or a validator (i.e., Last-Modified or an ETag)
#        present, or if they're already stale. By default, Squid will
#        not cache such responses because they usually can't be
#        reused. Note that such responses will be stale by default.
#
#        max-stale=NN provide a maximum staleness factor. Squid won't
#        serve objects more stale than this even if it failed to
#        validate the object. Default: use the max_stale global limit.
#
#    Basically a cached object is:
#
#        FRESH if expire > now, else STALE
#        STALE if age > max
#        FRESH if lm-factor < percent, else STALE
#        FRESH if age < min
#        else STALE
#
#    The refresh_pattern lines are checked in the order listed here.
#    The first entry which matches is used.  If none of the entries
#    match the default will be used.
#
#    Note, you must uncomment all the default lines if you want
#    to change one. The default setting is only active if none is
#    used.
#
#

#  TAG: quick_abort_min    (KB)
#Default:
# quick_abort_min 16 KB

#  TAG: quick_abort_max    (KB)
#Default:
# quick_abort_max 16 KB

#  TAG: quick_abort_pct    (percent)
#    The cache by default continues downloading aborted requests
#    which are almost completed (less than 16 KB remaining). This
#    may be undesirable on slow (e.g. SLIP) links and/or very busy
#    caches.  Impatient users may tie up file descriptors and
#    bandwidth by repeatedly requesting and immediately aborting
#    downloads.
#
#    When the user aborts a request, Squid will check the
#    quick_abort values to the amount of data transferred until
#    then.
#
#    If the transfer has less than 'quick_abort_min' KB remaining,
#    it will finish the retrieval.
#
#    If the transfer has more than 'quick_abort_max' KB remaining,
#    it will abort the retrieval.
#
#    If more than 'quick_abort_pct' of the transfer has completed,
#    it will finish the retrieval.
#
#    If you do not want any retrieval to continue after the client
#    has aborted, set both 'quick_abort_min' and 'quick_abort_max'
#    to '0 KB'.
#
#    If you want retrievals to always continue if they are being
#    cached set 'quick_abort_min' to '-1 KB'.
#Default:
# quick_abort_pct 95

#  TAG: read_ahead_gap    buffer-size
#    The amount of data the cache will buffer ahead of what has been
#    sent to the client when retrieving an object from another server.
#Default:
# read_ahead_gap 16 KB

#  TAG: negative_ttl    time-units
#    Set the Default Time-to-Live (TTL) for failed requests.
#    Certain types of failures (such as "connection refused" and
#    "404 Not Found") are able to be negatively-cached for a short time.
#    Modern web servers should provide Expires: header, however if they
#    do not this can provide a minimum TTL.
#    The default is not to cache errors with unknown expiry details.
#
#    Note that this is different from negative caching of DNS lookups.
#
#    WARNING: Doing this VIOLATES the HTTP standard.  Enabling
#    this feature could make you liable for problems which it
#    causes.
#Default:
# negative_ttl 0 seconds

#  TAG: positive_dns_ttl    time-units
#    Upper limit on how long Squid will cache positive DNS responses.
#    Default is 6 hours (360 minutes). This directive must be set
#    larger than negative_dns_ttl.
#Default:
# positive_dns_ttl 6 hours

#  TAG: negative_dns_ttl    time-units
#    Time-to-Live (TTL) for negative caching of failed DNS lookups.
#    This also sets the lower cache limit on positive lookups.
#    Minimum value is 1 second, and it is not recommendable to go
#    much below 10 seconds.
#Default:
# negative_dns_ttl 1 minutes

#  TAG: range_offset_limit    size [acl acl...]
#    usage: (size) [units] [[!]aclname]
#
#    Sets an upper limit on how far (number of bytes) into the file
#    a Range request    may be to cause Squid to prefetch the whole file.
#    If beyond this limit, Squid forwards the Range request as it is and
#    the result is NOT cached.
#
#    This is to stop a far ahead range request (lets say start at 17MB)
#    from making Squid fetch the whole object up to that point before
#    sending anything to the client.
#
#    Multiple range_offset_limit lines may be specified, and they will
#    be searched from top to bottom on each request until a match is found.
#    The first match found will be used.  If no line matches a request, the
#    default limit of 0 bytes will be used.
#
#    'size' is the limit specified as a number of units.
#
#    'units' specifies whether to use bytes, KB, MB, etc.
#    If no units are specified bytes are assumed.
#
#    A size of 0 causes Squid to never fetch more than the
#    client requested. (default)
#
#    A size of 'none' causes Squid to always fetch the object from the
#    beginning so it may cache the result. (2.0 style)
#
#    'aclname' is the name of a defined ACL.
#
#    NP: Using 'none' as the byte value here will override any quick_abort settings
#        that may otherwise apply to the range request. The range request will
#        be fully fetched from start to finish regardless of the client
#        actions. This affects bandwidth usage.
#Default:
# none

#  TAG: minimum_expiry_time    (seconds)
#    The minimum caching time according to (Expires - Date)
#    headers Squid honors if the object can't be revalidated.
#    The default is 60 seconds.
#
#    In reverse proxy environments it might be desirable to honor
#    shorter object lifetimes. It is most likely better to make
#    your server return a meaningful Last-Modified header however.
#
#    In ESI environments where page fragments often have short
#    lifetimes, this will often be best set to 0.
#Default:
# minimum_expiry_time 60 seconds

#  TAG: store_avg_object_size    (bytes)
#    Average object size, used to estimate number of objects your
#    cache can hold.  The default is 13 KB.
#
#    This is used to pre-seed the cache index memory allocation to
#    reduce expensive reallocate operations while handling clients
#    traffic. Too-large values may result in memory allocation during
#    peak traffic, too-small values will result in wasted memory.
#
#    Check the cache manager 'info' report metrics for the real
#    object sizes seen by your Squid before tuning this.
#Default:
# store_avg_object_size 13 KB

#  TAG: store_objects_per_bucket
#    Target number of objects per bucket in the store hash table.
#    Lowering this value increases the total number of buckets and
#    also the storage maintenance rate.  The default is 20.
#Default:
# store_objects_per_bucket 20

# HTTP OPTIONS
# -----------------------------------------------------------------------------

#  TAG: request_header_max_size    (KB)
#    This specifies the maximum size for HTTP headers in a request.
#    Request headers are usually relatively small (about 512 bytes).
#    Placing a limit on the request header size will catch certain
#    bugs (for example with persistent connections) and possibly
#    buffer-overflow or denial-of-service attacks.
#Default:
# request_header_max_size 64 KB

#  TAG: reply_header_max_size    (KB)
#    This specifies the maximum size for HTTP headers in a reply.
#    Reply headers are usually relatively small (about 512 bytes).
#    Placing a limit on the reply header size will catch certain
#    bugs (for example with persistent connections) and possibly
#    buffer-overflow or denial-of-service attacks.
#Default:
# reply_header_max_size 64 KB

#  TAG: request_body_max_size    (bytes)
#    This specifies the maximum size for an HTTP request body.
#    In other words, the maximum size of a PUT/POST request.
#    A user who attempts to send a request with a body larger
#    than this limit receives an "Invalid Request" error message.
#    If you set this parameter to a zero (the default), there will
#    be no limit imposed.
#
#    See also client_request_buffer_max_size for an alternative
#    limitation on client uploads which can be configured.
#Default:
# No limit.

#  TAG: client_request_buffer_max_size    (bytes)
#    This specifies the maximum buffer size of a client request.
#    It prevents squid eating too much memory when somebody uploads
#    a large file.
#Default:
# client_request_buffer_max_size 512 KB

#  TAG: broken_posts
#    A list of ACL elements which, if matched, causes Squid to send
#    an extra CRLF pair after the body of a PUT/POST request.
#
#    Some HTTP servers has broken implementations of PUT/POST,
#    and rely on an extra CRLF pair sent by some WWW clients.
#
#    Quote from RFC2616 section 4.1 on this matter:
#
#      Note: certain buggy HTTP/1.0 client implementations generate an
#      extra CRLF's after a POST request. To restate what is explicitly
#      forbidden by the BNF, an HTTP/1.1 client must not preface or follow
#      a request with an extra CRLF.
#
#    This clause only supports fast acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#
#Example:
# acl buggy_server url_regex ^http://....
# broken_posts allow buggy_server
#Default:
# Obey RFC 2616.

#  TAG: adaptation_uses_indirect_client    on|off
#    Controls whether the indirect client IP address (instead of the direct
#    client IP address) is passed to adaptation services.
#
#    See also: follow_x_forwarded_for adaptation_send_client_ip
#Default:
# adaptation_uses_indirect_client on

#  TAG: via    on|off
#    If set (default), Squid will include a Via header in requests and
#    replies as required by RFC2616.
#Default:
# via on

#  TAG: vary_ignore_expire    on|off
#    Many HTTP servers supporting Vary gives such objects
#    immediate expiry time with no cache-control header
#    when requested by a HTTP/1.0 client. This option
#    enables Squid to ignore such expiry times until
#    HTTP/1.1 is fully implemented.
#
#    WARNING: If turned on this may eventually cause some
#    varying objects not intended for caching to get cached.
#Default:
# vary_ignore_expire off

#  TAG: request_entities
#    Squid defaults to deny GET and HEAD requests with request entities,
#    as the meaning of such requests are undefined in the HTTP standard
#    even if not explicitly forbidden.
#
#    Set this directive to on if you have clients which insists
#    on sending request entities in GET or HEAD requests. But be warned
#    that there is server software (both proxies and web servers) which
#    can fail to properly process this kind of request which may make you
#    vulnerable to cache pollution attacks if enabled.
#Default:
# request_entities off

#  TAG: request_header_access
#    Usage: request_header_access header_name allow|deny [!]aclname ...
#
#    WARNING: Doing this VIOLATES the HTTP standard.  Enabling
#    this feature could make you liable for problems which it
#    causes.
#
#    This option replaces the old 'anonymize_headers' and the
#    older 'http_anonymizer' option with something that is much
#    more configurable. A list of ACLs for each header name allows
#    removal of specific header fields under specific conditions.
#
#    This option only applies to outgoing HTTP request headers (i.e.,
#    headers sent by Squid to the next HTTP hop such as a cache peer
#    or an origin server). The option has no effect during cache hit
#    detection. The equivalent adaptation vectoring point in ICAP
#    terminology is post-cache REQMOD.
#
#    The option is applied to individual outgoing request header
#    fields. For each request header field F, Squid uses the first
#    qualifying sets of request_header_access rules:
#
#        1. Rules with header_name equal to F's name.
#        2. Rules with header_name 'Other', provided F's name is not
#           on the hard-coded list of commonly used HTTP header names.
#        3. Rules with header_name 'All'.
#
#    Within that qualifying rule set, rule ACLs are checked as usual.
#    If ACLs of an "allow" rule match, the header field is allowed to
#    go through as is. If ACLs of a "deny" rule match, the header is
#    removed and request_header_replace is then checked to identify
#    if the removed header has a replacement. If no rules within the
#    set have matching ACLs, the header field is left as is.
#
#    For example, to achieve the same behavior as the old
#    'http_anonymizer standard' option, you should use:
#
#        request_header_access From deny all
#        request_header_access Referer deny all
#        request_header_access User-Agent deny all
#
#    Or, to reproduce the old 'http_anonymizer paranoid' feature
#    you should use:
#
#        request_header_access Authorization allow all
#        request_header_access Proxy-Authorization allow all
#        request_header_access Cache-Control allow all
#        request_header_access Content-Length allow all
#        request_header_access Content-Type allow all
#        request_header_access Date allow all
#        request_header_access Host allow all
#        request_header_access If-Modified-Since allow all
#        request_header_access Pragma allow all
#        request_header_access Accept allow all
#        request_header_access Accept-Charset allow all
#        request_header_access Accept-Encoding allow all
#        request_header_access Accept-Language allow all
#        request_header_access Connection allow all
#        request_header_access All deny all
#
#    HTTP reply headers are controlled with the reply_header_access directive.
#
#    By default, all headers are allowed (no anonymizing is performed).
#Default:
# No limits.

#  TAG: reply_header_access
#    Usage: reply_header_access header_name allow|deny [!]aclname ...
#
#    WARNING: Doing this VIOLATES the HTTP standard.  Enabling
#    this feature could make you liable for problems which it
#    causes.
#
#    This option only applies to reply headers, i.e., from the
#    server to the client.
#
#    This is the same as request_header_access, but in the other
#    direction. Please see request_header_access for detailed
#    documentation.
#
#    For example, to achieve the same behavior as the old
#    'http_anonymizer standard' option, you should use:
#
#        reply_header_access Server deny all
#        reply_header_access WWW-Authenticate deny all
#        reply_header_access Link deny all
#
#    Or, to reproduce the old 'http_anonymizer paranoid' feature
#    you should use:
#
#        reply_header_access Allow allow all
#        reply_header_access WWW-Authenticate allow all
#        reply_header_access Proxy-Authenticate allow all
#        reply_header_access Cache-Control allow all
#        reply_header_access Content-Encoding allow all
#        reply_header_access Content-Length allow all
#        reply_header_access Content-Type allow all
#        reply_header_access Date allow all
#        reply_header_access Expires allow all
#        reply_header_access Last-Modified allow all
#        reply_header_access Location allow all
#        reply_header_access Pragma allow all
#        reply_header_access Content-Language allow all
#        reply_header_access Retry-After allow all
#        reply_header_access Title allow all
#        reply_header_access Content-Disposition allow all
#        reply_header_access Connection allow all
#        reply_header_access All deny all
#
#    HTTP request headers are controlled with the request_header_access directive.
#
#    By default, all headers are allowed (no anonymizing is
#    performed).
#Default:
# No limits.

#  TAG: request_header_replace
#    Usage:   request_header_replace header_name message
#    Example: request_header_replace User-Agent Nutscrape/1.0 (CP/M; 8-bit)
#
#    This option allows you to change the contents of headers
#    denied with request_header_access above, by replacing them
#    with some fixed string.
#
#    This only applies to request headers, not reply headers.
#
#    By default, headers are removed if denied.
#Default:
# none

#  TAG: reply_header_replace
#        Usage:   reply_header_replace header_name message
#        Example: reply_header_replace Server Foo/1.0
#
#        This option allows you to change the contents of headers
#        denied with reply_header_access above, by replacing them
#        with some fixed string.
#
#        This only applies to reply headers, not request headers.
#
#        By default, headers are removed if denied.
#Default:
# none

#  TAG: request_header_add
#    Usage:   request_header_add field-name field-value [ acl ... ]
#    Example: request_header_add X-Client-CA "CA=%ssl::>cert_issuer" all
#
#    This option adds header fields to outgoing HTTP requests (i.e.,
#    request headers sent by Squid to the next HTTP hop such as a
#    cache peer or an origin server). The option has no effect during
#    cache hit detection. The equivalent adaptation vectoring point
#    in ICAP terminology is post-cache REQMOD.
#
#    Field-name is a token specifying an HTTP header name. If a
#    standard HTTP header name is used, Squid does not check whether
#    the new header conflicts with any existing headers or violates
#    HTTP rules. If the request to be modified already contains a
#    field with the same name, the old field is preserved but the
#    header field values are not merged.
#
#    Field-value is either a token or a quoted string. If quoted
#    string format is used, then the surrounding quotes are removed
#    while escape sequences and %macros are processed.
#
#    One or more Squid ACLs may be specified to restrict header
#    injection to matching requests. As always in squid.conf, all
#    ACLs in the ACL list must be satisfied for the insertion to
#    happen. The request_header_add supports fast ACLs only.
#
#    See also: reply_header_add.
#Default:
# none

#  TAG: reply_header_add
#    Usage:   reply_header_add field-name field-value [ acl ... ]
#    Example: reply_header_add X-Client-CA "CA=%ssl::>cert_issuer" all
#
#    This option adds header fields to outgoing HTTP responses (i.e., response
#    headers delivered by Squid to the client). This option has no effect on
#    cache hit detection. The equivalent adaptation vectoring point in
#    ICAP terminology is post-cache RESPMOD. This option does not apply to
#    successful CONNECT replies.
#
#    Field-name is a token specifying an HTTP header name. If a
#    standard HTTP header name is used, Squid does not check whether
#    the new header conflicts with any existing headers or violates
#    HTTP rules. If the response to be modified already contains a
#    field with the same name, the old field is preserved but the
#    header field values are not merged.
#
#    Field-value is either a token or a quoted string. If quoted
#    string format is used, then the surrounding quotes are removed
#    while escape sequences and %macros are processed.
#
#    One or more Squid ACLs may be specified to restrict header
#    injection to matching responses. As always in squid.conf, all
#    ACLs in the ACL list must be satisfied for the insertion to
#    happen. The reply_header_add option supports fast ACLs only.
#
#    See also: request_header_add.
#Default:
# none

#  TAG: note
#    This option used to log custom information about the master
#    transaction. For example, an admin may configure Squid to log
#    which "user group" the transaction belongs to, where "user group"
#    will be determined based on a set of ACLs and not [just]
#    authentication information.
#    Values of key/value pairs can be logged using %{key}note macros:
#
#        note key value acl ...
#        logformat myFormat ... %{key}note ...
#
#    This clause only supports fast acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#Default:
# none

#  TAG: relaxed_header_parser    on|off|warn
#    In the default "on" setting Squid accepts certain forms
#    of non-compliant HTTP messages where it is unambiguous
#    what the sending application intended even if the message
#    is not correctly formatted. The messages is then normalized
#    to the correct form when forwarded by Squid.
#
#    If set to "warn" then a warning will be emitted in cache.log
#    each time such HTTP error is encountered.
#
#    If set to "off" then such HTTP errors will cause the request
#    or response to be rejected.
#Default:
# relaxed_header_parser on

#  TAG: collapsed_forwarding    (on|off)
#       This option controls whether Squid is allowed to merge multiple
#       potentially cachable requests for the same URI before Squid knows
#       whether the response is going to be cachable.
#
#       When enabled, instead of forwarding each concurrent request for
#       the same URL, Squid just sends the first of them. The other, so
#       called "collapsed" requests, wait for the response to the first
#       request and, if it happens to be cachable, use that response.
#       Here, "concurrent requests" means "received after the first
#       request headers were parsed and before the corresponding response
#       headers were parsed".
#
#       This feature is disabled by default: enabling collapsed
#       forwarding needlessly delays forwarding requests that look
#       cachable (when they are collapsed) but then need to be forwarded
#       individually anyway because they end up being for uncachable
#       content. However, in some cases, such as acceleration of highly
#       cachable content with periodic or grouped expiration times, the
#       gains from collapsing [large volumes of simultaneous refresh
#       requests] outweigh losses from such delays.
#
#       Squid collapses two kinds of requests: regular client requests
#       received on one of the listening ports and internal "cache
#       revalidation" requests which are triggered by those regular
#       requests hitting a stale cached object. Revalidation collapsing
#       is currently disabled for Squid instances containing SMP-aware
#       disk or memory caches and for Vary-controlled cached objects.
#Default:
# collapsed_forwarding off

#  TAG: collapsed_forwarding_access
#    Use this directive to restrict collapsed forwarding to a subset of
#    eligible requests. The directive is checked for regular HTTP
#    requests, internal revalidation requests, and HTCP/ICP requests.
#
#        collapsed_forwarding_access allow|deny [!]aclname ...
#
#    This directive cannot force collapsing. It has no effect on
#    collapsing unless collapsed_forwarding is 'on', and all other
#    collapsing preconditions are satisfied.
#
#    * A denied request will not collapse, and future transactions will
#      not collapse on it (even if they are allowed to collapse).
#
#    * An allowed request may collapse, or future transactions may
#      collapse on it (provided they are allowed to collapse).
#
#    This directive is evaluated before receiving HTTP response headers
#    and without access to Squid-to-peer connection (if any).
#
#    Only fast ACLs are supported.
#
#    See also: collapsed_forwarding.
#Default:
# Requests may be collapsed if collapsed_forwarding is on.

#  TAG: shared_transient_entries_limit    (number of entries)
#    This directive limits the size of a table used for sharing current
#    transaction information among SMP workers. A table entry stores meta
#    information about a single cache entry being delivered to Squid
#    client(s) by one or more SMP workers. A single table entry consumes
#    less than 128 shared memory bytes.
#
#    The limit should be significantly larger than the number of
#    concurrent non-collapsed cachable responses leaving Squid. For a
#    cache that handles less than 5000 concurrent requests, the default
#    setting of 16384 should be plenty.
#
#    Using excessively large values wastes shared memory. Limiting the
#    table size too much results in hash collisions, leading to lower hit
#    ratio and missed SMP request collapsing opportunities: Transactions
#    left without a table entry cannot cache their responses and are
#    invisible to other concurrent requests for the same resource.
#
#    A zero limit is allowed but unsupported. A positive small limit
#    lowers hit ratio, but zero limit disables a lot of essential
#    synchronization among SMP workers, leading to HTTP violations (e.g.,
#    stale hit responses). It also disables shared collapsed forwarding:
#    A worker becomes unable to collapse its requests on transactions in
#    other workers, resulting in more trips to the origin server and more
#    cache thrashing.
#Default:
# shared_transient_entries_limit 16384

# TIMEOUTS
# -----------------------------------------------------------------------------

#  TAG: forward_timeout    time-units
#    This parameter specifies how long Squid should at most attempt in
#    finding a forwarding path for the request before giving up.
#Default:
# forward_timeout 4 minutes

#  TAG: connect_timeout    time-units
#    This parameter specifies how long to wait for the TCP connect to
#    the requested server or peer to complete before Squid should
#    attempt to find another path where to forward the request.
#Default:
# connect_timeout 1 minute

#  TAG: peer_connect_timeout    time-units
#    This parameter specifies how long to wait for a pending TCP
#    connection to a peer cache.  The default is 30 seconds.   You
#    may also set different timeout values for individual neighbors
#    with the 'connect-timeout' option on a 'cache_peer' line.
#Default:
# peer_connect_timeout 30 seconds

#  TAG: read_timeout    time-units
#    Applied on peer server connections.
#
#    After each successful read(), the timeout will be extended by this
#    amount.  If no data is read again after this amount of time,
#    the request is aborted and logged with ERR_READ_TIMEOUT.
#
#    The default is 15 minutes.
#Default:
# read_timeout 15 minutes

#  TAG: write_timeout    time-units
#    This timeout is tracked for all connections that have data
#    available for writing and are waiting for the socket to become
#    ready. After each successful write, the timeout is extended by
#    the configured amount. If Squid has data to write but the
#    connection is not ready for the configured duration, the
#    transaction associated with the connection is terminated. The
#    default is 15 minutes.
#Default:
# write_timeout 15 minutes

#  TAG: request_timeout
#    How long to wait for complete HTTP request headers after initial
#    connection establishment.
#Default:
# request_timeout 5 minutes

#  TAG: request_start_timeout
#    How long to wait for the first request byte after initial
#    connection establishment.
#Default:
# request_start_timeout 5 minutes

#  TAG: client_idle_pconn_timeout
#    How long to wait for the next HTTP request on a persistent
#    client connection after the previous request completes.
#Default:
# client_idle_pconn_timeout 2 minutes

#  TAG: ftp_client_idle_timeout
#    How long to wait for an FTP request on a connection to Squid ftp_port.
#    Many FTP clients do not deal with idle connection closures well,
#    necessitating a longer default timeout than client_idle_pconn_timeout
#    used for incoming HTTP requests.
#Default:
# ftp_client_idle_timeout 30 minutes

#  TAG: client_lifetime    time-units
#    The maximum amount of time a client (browser) is allowed to
#    remain connected to the cache process.  This protects the Cache
#    from having a lot of sockets (and hence file descriptors) tied up
#    in a CLOSE_WAIT state from remote clients that go away without
#    properly shutting down (either because of a network failure or
#    because of a poor client implementation).  The default is one
#    day, 1440 minutes.
#
#    NOTE:  The default value is intended to be much larger than any
#    client would ever need to be connected to your cache.  You
#    should probably change client_lifetime only as a last resort.
#    If you seem to have many client connections tying up
#    filedescriptors, we recommend first tuning the read_timeout,
#    request_timeout, persistent_request_timeout and quick_abort values.
#Default:
# client_lifetime 1 day

#  TAG: pconn_lifetime    time-units
#    Desired maximum lifetime of a persistent connection.
#    When set, Squid will close a now-idle persistent connection that
#    exceeded configured lifetime instead of moving the connection into
#    the idle connection pool (or equivalent). No effect on ongoing/active
#    transactions. Connection lifetime is the time period from the
#    connection acceptance or opening time until "now".
#
#    This limit is useful in environments with long-lived connections
#    where Squid configuration or environmental factors change during a
#    single connection lifetime. If unrestricted, some connections may
#    last for hours and even days, ignoring those changes that should
#    have affected their behavior or their existence.
#
#    Currently, a new lifetime value supplied via Squid reconfiguration
#    has no effect on already idle connections unless they become busy.
#
#    When set to '0' this limit is not used.
#Default:
# pconn_lifetime 0 seconds

#  TAG: half_closed_clients
#    Some clients may shutdown the sending side of their TCP
#    connections, while leaving their receiving sides open.    Sometimes,
#    Squid can not tell the difference between a half-closed and a
#    fully-closed TCP connection.
#
#    By default, Squid will immediately close client connections when
#    read(2) returns "no more data to read."
#
#    Change this option to 'on' and Squid will keep open connections
#    until a read(2) or write(2) on the socket returns an error.
#    This may show some benefits for reverse proxies. But if not
#    it is recommended to leave OFF.
#Default:
# half_closed_clients off

#  TAG: server_idle_pconn_timeout
#    Timeout for idle persistent connections to servers and other
#    proxies.
#Default:
# server_idle_pconn_timeout 1 minute

#  TAG: ident_timeout
#    Maximum time to wait for IDENT lookups to complete.
#
#    If this is too high, and you enabled IDENT lookups from untrusted
#    users, you might be susceptible to denial-of-service by having
#    many ident requests going at once.
#Default:
# ident_timeout 10 seconds

#  TAG: shutdown_lifetime    time-units
#    When SIGTERM or SIGHUP is received, the cache is put into
#    "shutdown pending" mode until all active sockets are closed.
#    This value is the lifetime to set for all open descriptors
#    during shutdown mode.  Any active clients after this many
#    seconds will receive a 'timeout' message.
#Default:
# shutdown_lifetime 30 seconds

# ADMINISTRATIVE PARAMETERS
# -----------------------------------------------------------------------------

#  TAG: cache_mgr
#    Email-address of local cache manager who will receive
#    mail if the cache dies.  The default is "webmaster".
#Default:
# cache_mgr webmaster

#  TAG: mail_from
#    From: email-address for mail sent when the cache dies.
#    The default is to use 'squid@unique_hostname'.
#
#    See also: unique_hostname directive.
#Default:
# none

#  TAG: mail_program
#    Email program used to send mail if the cache dies.
#    The default is "mail". The specified program must comply
#    with the standard Unix mail syntax:
#      mail-program recipient < mailfile
#
#    Optional command line options can be specified.
#Default:
# mail_program mail

#  TAG: cache_effective_user
#    If you start Squid as root, it will change its effective/real
#    UID/GID to the user specified below.  The default is to change
#    to UID of proxy.
#    see also; cache_effective_group
#Default:
# cache_effective_user proxy

#  TAG: cache_effective_group
#    Squid sets the GID to the effective user's default group ID
#    (taken from the password file) and supplementary group list
#    from the groups membership.
#
#    If you want Squid to run with a specific GID regardless of
#    the group memberships of the effective user then set this
#    to the group (or GID) you want Squid to run as. When set
#    all other group privileges of the effective user are ignored
#    and only this GID is effective. If Squid is not started as
#    root the user starting Squid MUST be member of the specified
#    group.
#
#    This option is not recommended by the Squid Team.
#    Our preference is for administrators to configure a secure
#    user account for squid with UID/GID matching system policies.
#Default:
# Use system group memberships of the cache_effective_user account

#  TAG: httpd_suppress_version_string    on|off
#    Suppress Squid version string info in HTTP headers and HTML error pages.
#Default:
# httpd_suppress_version_string off

#  TAG: visible_hostname
#    If you want to present a special hostname in error messages, etc,
#    define this.  Otherwise, the return value of gethostname()
#    will be used. If you have multiple caches in a cluster and
#    get errors about IP-forwarding you must set them to have individual
#    names with this setting.
#Default:
# visible_hostname debian-bullseye

#  TAG: unique_hostname
#    If you want to have multiple machines with the same
#    'visible_hostname' you must give each machine a different
#    'unique_hostname' so forwarding loops can be detected.
#Default:
# Copy the value from visible_hostname

#  TAG: hostname_aliases
#    A list of other DNS names your cache has.
#Default:
# none

#  TAG: umask
#    Minimum umask which should be enforced while the proxy
#    is running, in addition to the umask set at startup.
#
#    For a traditional octal representation of umasks, start
#        your value with 0.
#Default:
umask 022

# OPTIONS FOR THE CACHE REGISTRATION SERVICE
# -----------------------------------------------------------------------------
#
#    This section contains parameters for the (optional) cache
#    announcement service.  This service is provided to help
#    cache administrators locate one another in order to join or
#    create cache hierarchies.
#
#    An 'announcement' message is sent (via UDP) to the registration
#    service by Squid.  By default, the announcement message is NOT
#    SENT unless you enable it with 'announce_period' below.
#
#    The announcement message includes your hostname, plus the
#    following information from this configuration file:
#
#        http_port
#        icp_port
#        cache_mgr
#
#    All current information is processed regularly and made
#    available on the Web at http://www.ircache.net/Cache/Tracker/.

#  TAG: announce_period
#    This is how frequently to send cache announcements.
#
#    To enable announcing your cache, just set an announce period.
#
#    Example:
#        announce_period 1 day
#Default:
# Announcement messages disabled.

#  TAG: announce_host
#    Set the hostname where announce registration messages will be sent.
#
#    See also announce_port and announce_file
#Default:
# announce_host tracker.ircache.net

#  TAG: announce_file
#    The contents of this file will be included in the announce
#    registration messages.
#Default:
# none

#  TAG: announce_port
#    Set the port where announce registration messages will be sent.
#
#    See also announce_host and announce_file
#Default:
# announce_port 3131

# HTTPD-ACCELERATOR OPTIONS
# -----------------------------------------------------------------------------

#  TAG: httpd_accel_surrogate_id
#    Surrogates (http://www.esi.org/architecture_spec_1.0.html)
#    need an identification token to allow control targeting. Because
#    a farm of surrogates may all perform the same tasks, they may share
#    an identification token.
#
#    When the surrogate is a reverse-proxy, this ID is also
#    used as cdn-id for CDN-Loop detection (RFC 8586).
#Default:
# visible_hostname is used if no specific ID is set.

#  TAG: http_accel_surrogate_remote    on|off
#    Remote surrogates (such as those in a CDN) honour the header
#    "Surrogate-Control: no-store-remote".
#
#    Set this to on to have squid behave as a remote surrogate.
#Default:
# http_accel_surrogate_remote off

#  TAG: esi_parser    libxml2|expat
#    Selects the XML parsing library to use when interpreting responses with
#    Edge Side Includes.
#
#    To disable ESI handling completely, ./configure Squid with --disable-esi.
#Default:
# Selects libxml2 if available at ./configure time or libexpat otherwise.

# DELAY POOL PARAMETERS
# -----------------------------------------------------------------------------

#  TAG: delay_pools
#    This represents the number of delay pools to be used.  For example,
#    if you have one class 2 delay pool and one class 3 delays pool, you
#    have a total of 2 delay pools.
#
#    See also delay_parameters, delay_class, delay_access for pool
#    configuration details.
#Default:
# delay_pools 0

#  TAG: delay_class
#    This defines the class of each delay pool.  There must be exactly one
#    delay_class line for each delay pool.  For example, to define two
#    delay pools, one of class 2 and one of class 3, the settings above
#    and here would be:
#
#    Example:
#        delay_pools 4      # 4 delay pools
#        delay_class 1 2    # pool 1 is a class 2 pool
#        delay_class 2 3    # pool 2 is a class 3 pool
#        delay_class 3 4    # pool 3 is a class 4 pool
#        delay_class 4 5    # pool 4 is a class 5 pool
#
#    The delay pool classes are:
#
#        class 1        Everything is limited by a single aggregate
#                bucket.
#
#        class 2     Everything is limited by a single aggregate
#                bucket as well as an "individual" bucket chosen
#                from bits 25 through 32 of the IPv4 address.
#
#        class 3        Everything is limited by a single aggregate
#                bucket as well as a "network" bucket chosen
#                from bits 17 through 24 of the IP address and a
#                "individual" bucket chosen from bits 17 through
#                32 of the IPv4 address.
#
#        class 4        Everything in a class 3 delay pool, with an
#                additional limit on a per user basis. This
#                only takes effect if the username is established
#                in advance - by forcing authentication in your
#                http_access rules.
#
#        class 5        Requests are grouped according their tag (see
#                external_acl's tag= reply).
#
#
#    Each pool also requires a delay_parameters directive to configure the pool size
#    and speed limits used whenever the pool is applied to a request. Along with
#    a set of delay_access directives to determine when it is used.
#
#    NOTE: If an IP address is a.b.c.d
#        -> bits 25 through 32 are "d"
#        -> bits 17 through 24 are "c"
#        -> bits 17 through 32 are "c * 256 + d"
#
#    NOTE-2: Due to the use of bitmasks in class 2,3,4 pools they only apply to
#        IPv4 traffic. Class 1 and 5 pools may be used with IPv6 traffic.
#
#    This clause only supports fast acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#
#    See also delay_parameters and delay_access.
#Default:
# none

#  TAG: delay_access
#    This is used to determine which delay pool a request falls into.
#
#    delay_access is sorted per pool and the matching starts with pool 1,
#    then pool 2, ..., and finally pool N. The first delay pool where the
#    request is allowed is selected for the request. If it does not allow
#    the request to any pool then the request is not delayed (default).
#
#    For example, if you want some_big_clients in delay
#    pool 1 and lotsa_little_clients in delay pool 2:
#
#        delay_access 1 allow some_big_clients
#        delay_access 1 deny all
#        delay_access 2 allow lotsa_little_clients
#        delay_access 2 deny all
#        delay_access 3 allow authenticated_clients
#
#    See also delay_parameters and delay_class.
#
#Default:
# Deny using the pool, unless allow rules exist in squid.conf for the pool.

#  TAG: delay_parameters
#    This defines the parameters for a delay pool.  Each delay pool has
#    a number of "buckets" associated with it, as explained in the
#    description of delay_class.
#
#    For a class 1 delay pool, the syntax is:
#        delay_class pool 1
#        delay_parameters pool aggregate
#
#    For a class 2 delay pool:
#        delay_class pool 2
#        delay_parameters pool aggregate individual
#
#    For a class 3 delay pool:
#        delay_class pool 3
#        delay_parameters pool aggregate network individual
#
#    For a class 4 delay pool:
#        delay_class pool 4
#        delay_parameters pool aggregate network individual user
#
#    For a class 5 delay pool:
#        delay_class pool 5
#        delay_parameters pool tagrate
#
#    The option variables are:
#
#        pool        a pool number - ie, a number between 1 and the
#                number specified in delay_pools as used in
#                delay_class lines.
#
#        aggregate    the speed limit parameters for the aggregate bucket
#                (class 1, 2, 3).
#
#        individual    the speed limit parameters for the individual
#                buckets (class 2, 3).
#
#        network        the speed limit parameters for the network buckets
#                (class 3).
#
#        user        the speed limit parameters for the user buckets
#                (class 4).
#
#        tagrate        the speed limit parameters for the tag buckets
#                (class 5).
#
#    A pair of delay parameters is written restore/maximum, where restore is
#    the number of bytes (not bits - modem and network speeds are usually
#    quoted in bits) per second placed into the bucket, and maximum is the
#    maximum number of bytes which can be in the bucket at any time.
#
#    There must be one delay_parameters line for each delay pool.
#
#
#    For example, if delay pool number 1 is a class 2 delay pool as in the
#    above example, and is being used to strictly limit each host to 64Kbit/sec
#    (plus overheads), with no overall limit, the line is:
#
#        delay_parameters 1 none 8000/8000
#
#    Note that 8 x 8K Byte/sec -> 64K bit/sec.
#
#    Note that the word 'none' is used to represent no limit.
#
#
#    And, if delay pool number 2 is a class 3 delay pool as in the above
#    example, and you want to limit it to a total of 256Kbit/sec (strict limit)
#    with each 8-bit network permitted 64Kbit/sec (strict limit) and each
#    individual host permitted 4800bit/sec with a bucket maximum size of 64Kbits
#    to permit a decent web page to be downloaded at a decent speed
#    (if the network is not being limited due to overuse) but slow down
#    large downloads more significantly:
#
#        delay_parameters 2 32000/32000 8000/8000 600/8000
#
#    Note that 8 x  32K Byte/sec ->  256K bit/sec.
#          8 x   8K Byte/sec ->   64K bit/sec.
#          8 x 600  Byte/sec -> 4800  bit/sec.
#
#
#    Finally, for a class 4 delay pool as in the example - each user will
#    be limited to 128Kbits/sec no matter how many workstations they are logged into.:
#
#        delay_parameters 4 32000/32000 8000/8000 600/64000 16000/16000
#
#
#    See also delay_class and delay_access.
#
#Default:
# none

#  TAG: delay_initial_bucket_level    (percent, 0-100)
#    The initial bucket percentage is used to determine how much is put
#    in each bucket when squid starts, is reconfigured, or first notices
#    a host accessing it (in class 2 and class 3, individual hosts and
#    networks only have buckets associated with them once they have been
#    "seen" by squid).
#Default:
# delay_initial_bucket_level 50

# CLIENT DELAY POOL PARAMETERS
# -----------------------------------------------------------------------------

#  TAG: client_delay_pools
#    This option specifies the number of client delay pools used. It must
#    preceed other client_delay_* options.
#
#    Example:
#        client_delay_pools 2
#
#    See also client_delay_parameters and client_delay_access.
#Default:
# client_delay_pools 0

#  TAG: client_delay_initial_bucket_level    (percent, 0-no_limit)
#    This option determines the initial bucket size as a percentage of
#    max_bucket_size from client_delay_parameters. Buckets are created
#    at the time of the "first" connection from the matching IP. Idle
#    buckets are periodically deleted up.
#
#    You can specify more than 100 percent but note that such "oversized"
#    buckets are not refilled until their size goes down to max_bucket_size
#    from client_delay_parameters.
#
#    Example:
#        client_delay_initial_bucket_level 50
#Default:
# client_delay_initial_bucket_level 50

#  TAG: client_delay_parameters
#
#    This option configures client-side bandwidth limits using the
#    following format:
#
#        client_delay_parameters pool speed_limit max_bucket_size
#
#    pool is an integer ID used for client_delay_access matching.
#
#    speed_limit is bytes added to the bucket per second.
#
#    max_bucket_size is the maximum size of a bucket, enforced after any
#    speed_limit additions.
#
#    Please see the delay_parameters option for more information and
#    examples.
#
#    Example:
#        client_delay_parameters 1 1024 2048
#        client_delay_parameters 2 51200 16384
#
#    See also client_delay_access.
#
#Default:
# none

#  TAG: client_delay_access
#    This option determines the client-side delay pool for the
#    request:
#
#        client_delay_access pool_ID allow|deny acl_name
#
#    All client_delay_access options are checked in their pool ID
#    order, starting with pool 1. The first checked pool with allowed
#    request is selected for the request. If no ACL matches or there
#    are no client_delay_access options, the request bandwidth is not
#    limited.
#
#    The ACL-selected pool is then used to find the
#    client_delay_parameters for the request. Client-side pools are
#    not used to aggregate clients. Clients are always aggregated
#    based on their source IP addresses (one bucket per source IP).
#
#    This clause only supports fast acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#    Additionally, only the client TCP connection details are available.
#    ACLs testing HTTP properties will not work.
#
#    Please see delay_access for more examples.
#
#    Example:
#        client_delay_access 1 allow low_rate_network
#        client_delay_access 2 allow vips_network
#
#
#    See also client_delay_parameters and client_delay_pools.
#Default:
# Deny use of the pool, unless allow rules exist in squid.conf for the pool.

#  TAG: response_delay_pool
#    This option configures client response bandwidth limits using the
#    following format:
#
#    response_delay_pool name [option=value] ...
#
#    name    the response delay pool name
#
#    available options:
#
#        individual-restore    The speed limit of an individual
#                    bucket(bytes/s). To be used in conjunction
#                    with 'individual-maximum'.
#
#        individual-maximum    The maximum number of bytes which can
#                    be placed into the individual bucket. To be used
#                    in conjunction with 'individual-restore'.
#
#        aggregate-restore    The speed limit for the aggregate
#                    bucket(bytes/s). To be used in conjunction with
#                    'aggregate-maximum'.
#
#        aggregate-maximum    The maximum number of bytes which can
#                       be placed into the aggregate bucket. To be used
#                    in conjunction with 'aggregate-restore'.
#
#        initial-bucket-level    The initial bucket size as a percentage
#                    of individual-maximum.
#
#    Individual and(or) aggregate bucket options may not be specified,
#       meaning no individual and(or) aggregate speed limitation.
#    See also response_delay_pool_access and delay_parameters for
#    terminology details.
#Default:
# none

#  TAG: response_delay_pool_access
#    Determines whether a specific named response delay pool is used
#    for the transaction. The syntax for this directive is:
#
#    response_delay_pool_access pool_name allow|deny acl_name
#
#    All response_delay_pool_access options are checked in the order
#    they appear in this configuration file. The first rule with a
#    matching ACL wins. If (and only if) an "allow" rule won, Squid
#    assigns the response to the corresponding named delay pool.
#Default:
# Deny use of the pool, unless allow rules exist in squid.conf for the pool.

# WCCPv1 AND WCCPv2 CONFIGURATION OPTIONS
# -----------------------------------------------------------------------------

#  TAG: wccp_router
#    Use this option to define your WCCP ``home'' router for
#    Squid.
#
#    wccp_router supports a single WCCP(v1) router
#
#    wccp2_router supports multiple WCCPv2 routers
#
#    only one of the two may be used at the same time and defines
#    which version of WCCP to use.
#Default:
# WCCP disabled.

#  TAG: wccp2_router
#    Use this option to define your WCCP ``home'' router for
#    Squid.
#
#    wccp_router supports a single WCCP(v1) router
#
#    wccp2_router supports multiple WCCPv2 routers
#
#    only one of the two may be used at the same time and defines
#    which version of WCCP to use.
#Default:
# WCCPv2 disabled.

#  TAG: wccp_version
#    This directive is only relevant if you need to set up WCCP(v1)
#    to some very old and end-of-life Cisco routers. In all other
#    setups it must be left unset or at the default setting.
#    It defines an internal version in the WCCP(v1) protocol,
#    with version 4 being the officially documented protocol.
#
#    According to some users, Cisco IOS 11.2 and earlier only
#    support WCCP version 3.  If you're using that or an earlier
#    version of IOS, you may need to change this value to 3, otherwise
#    do not specify this parameter.
#Default:
# wccp_version 4

#  TAG: wccp2_rebuild_wait
#    If this is enabled Squid will wait for the cache dir rebuild to finish
#    before sending the first wccp2 HereIAm packet
#Default:
# wccp2_rebuild_wait on

#  TAG: wccp2_forwarding_method
#    WCCP2 allows the setting of forwarding methods between the
#    router/switch and the cache.  Valid values are as follows:
#
#    gre - GRE encapsulation (forward the packet in a GRE/WCCP tunnel)
#    l2  - L2 redirect (forward the packet using Layer 2/MAC rewriting)
#
#    Currently (as of IOS 12.4) cisco routers only support GRE.
#    Cisco switches only support the L2 redirect assignment method.
#Default:
# wccp2_forwarding_method gre

#  TAG: wccp2_return_method
#    WCCP2 allows the setting of return methods between the
#    router/switch and the cache for packets that the cache
#    decides not to handle.  Valid values are as follows:
#
#    gre - GRE encapsulation (forward the packet in a GRE/WCCP tunnel)
#    l2  - L2 redirect (forward the packet using Layer 2/MAC rewriting)
#
#    Currently (as of IOS 12.4) cisco routers only support GRE.
#    Cisco switches only support the L2 redirect assignment.
#
#    If the "ip wccp redirect exclude in" command has been
#    enabled on the cache interface, then it is still safe for
#    the proxy server to use a l2 redirect method even if this
#    option is set to GRE.
#Default:
# wccp2_return_method gre

#  TAG: wccp2_assignment_method
#    WCCP2 allows the setting of methods to assign the WCCP hash
#    Valid values are as follows:
#
#    hash - Hash assignment
#    mask - Mask assignment
#
#    As a general rule, cisco routers support the hash assignment method
#    and cisco switches support the mask assignment method.
#Default:
# wccp2_assignment_method hash

#  TAG: wccp2_service
#    WCCP2 allows for multiple traffic services. There are two
#    types: "standard" and "dynamic". The standard type defines
#    one service id - http (id 0). The dynamic service ids can be from
#    51 to 255 inclusive.  In order to use a dynamic service id
#    one must define the type of traffic to be redirected; this is done
#    using the wccp2_service_info option.
#
#    The "standard" type does not require a wccp2_service_info option,
#    just specifying the service id will suffice.
#
#    MD5 service authentication can be enabled by adding
#    "password=<password>" to the end of this service declaration.
#
#    Examples:
#
#    wccp2_service standard 0    # for the 'web-cache' standard service
#    wccp2_service dynamic 80    # a dynamic service type which will be
#                    # fleshed out with subsequent options.
#    wccp2_service standard 0 password=foo
#Default:
# Use the 'web-cache' standard service.

#  TAG: wccp2_service_info
#    Dynamic WCCPv2 services require further information to define the
#    traffic you wish to have diverted.
#
#    The format is:
#
#    wccp2_service_info <id> protocol=<protocol> flags=<flag>,<flag>..
#        priority=<priority> ports=<port>,<port>..
#
#    The relevant WCCPv2 flags:
#    + src_ip_hash, dst_ip_hash
#    + source_port_hash, dst_port_hash
#    + src_ip_alt_hash, dst_ip_alt_hash
#    + src_port_alt_hash, dst_port_alt_hash
#    + ports_source
#
#    The port list can be one to eight entries.
#
#    Example:
#
#    wccp2_service_info 80 protocol=tcp flags=src_ip_hash,ports_source
#        priority=240 ports=80
#
#    Note: the service id must have been defined by a previous
#    'wccp2_service dynamic <id>' entry.
#Default:
# none

#  TAG: wccp2_weight
#    Each cache server gets assigned a set of the destination
#    hash proportional to their weight.
#Default:
# wccp2_weight 10000

#  TAG: wccp_address
#    Use this option if you require WCCP(v1) to use a specific
#    interface address.
#
#    The default behavior is to not bind to any specific address.
#Default:
# Address selected by the operating system.

#  TAG: wccp2_address
#    Use this option if you require WCCPv2 to use a specific
#    interface address.
#
#    The default behavior is to not bind to any specific address.
#Default:
# Address selected by the operating system.

# PERSISTENT CONNECTION HANDLING
# -----------------------------------------------------------------------------
#
# Also see "pconn_timeout" in the TIMEOUTS section

#  TAG: client_persistent_connections
#    Persistent connection support for clients.
#    Squid uses persistent connections (when allowed). You can use
#    this option to disable persistent connections with clients.
#Default:
# client_persistent_connections on

#  TAG: server_persistent_connections
#    Persistent connection support for servers.
#    Squid uses persistent connections (when allowed). You can use
#    this option to disable persistent connections with servers.
#Default:
# server_persistent_connections on

#  TAG: persistent_connection_after_error
#    With this directive the use of persistent connections after
#    HTTP errors can be disabled. Useful if you have clients
#    who fail to handle errors on persistent connections proper.
#Default:
# persistent_connection_after_error on

#  TAG: detect_broken_pconn
#    Some servers have been found to incorrectly signal the use
#    of HTTP/1.0 persistent connections even on replies not
#    compatible, causing significant delays. This server problem
#    has mostly been seen on redirects.
#
#    By enabling this directive Squid attempts to detect such
#    broken replies and automatically assume the reply is finished
#    after 10 seconds timeout.
#Default:
# detect_broken_pconn off

# CACHE DIGEST OPTIONS
# -----------------------------------------------------------------------------

#  TAG: digest_generation
#    This controls whether the server will generate a Cache Digest
#    of its contents.  By default, Cache Digest generation is
#    enabled if Squid is compiled with --enable-cache-digests defined.
#Default:
# digest_generation on

#  TAG: digest_bits_per_entry
#    This is the number of bits of the server's Cache Digest which
#    will be associated with the Digest entry for a given HTTP
#    Method and URL (public key) combination.  The default is 5.
#Default:
# digest_bits_per_entry 5

#  TAG: digest_rebuild_period    (seconds)
#    This is the wait time between Cache Digest rebuilds.
#Default:
# digest_rebuild_period 1 hour

#  TAG: digest_rewrite_period    (seconds)
#    This is the wait time between Cache Digest writes to
#    disk.
#Default:
# digest_rewrite_period 1 hour

#  TAG: digest_swapout_chunk_size    (bytes)
#    This is the number of bytes of the Cache Digest to write to
#    disk at a time.  It defaults to 4096 bytes (4KB), the Squid
#    default swap page.
#Default:
# digest_swapout_chunk_size 4096 bytes

#  TAG: digest_rebuild_chunk_percentage    (percent, 0-100)
#    This is the percentage of the Cache Digest to be scanned at a
#    time.  By default it is set to 10% of the Cache Digest.
#Default:
# digest_rebuild_chunk_percentage 10

# SNMP OPTIONS
# -----------------------------------------------------------------------------

#  TAG: snmp_port
#    The port number where Squid listens for SNMP requests. To enable
#    SNMP support set this to a suitable port number. Port number
#    3401 is often used for the Squid SNMP agent. By default it's
#    set to "0" (disabled)
#
#    Example:
#        snmp_port 3401
#Default:
# SNMP disabled.

#  TAG: snmp_access
#    Allowing or denying access to the SNMP port.
#
#    All access to the agent is denied by default.
#    usage:
#
#    snmp_access allow|deny [!]aclname ...
#
#    This clause only supports fast acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#
#Example:
# snmp_access allow snmppublic localhost
# snmp_access deny all
#Default:
# Deny, unless rules exist in squid.conf.

#  TAG: snmp_incoming_address
#    Just like 'udp_incoming_address', but for the SNMP port.
#
#    snmp_incoming_address    is used for the SNMP socket receiving
#                messages from SNMP agents.
#
#    The default snmp_incoming_address is to listen on all
#    available network interfaces.
#Default:
# Accept SNMP packets from all machine interfaces.

#  TAG: snmp_outgoing_address
#    Just like 'udp_outgoing_address', but for the SNMP port.
#
#    snmp_outgoing_address    is used for SNMP packets returned to SNMP
#                agents.
#
#    If snmp_outgoing_address is not set it will use the same socket
#    as snmp_incoming_address. Only change this if you want to have
#    SNMP replies sent using another address than where this Squid
#    listens for SNMP queries.
#
#    NOTE, snmp_incoming_address and snmp_outgoing_address can not have
#    the same value since they both use the same port.
#Default:
# Use snmp_incoming_address or an address selected by the operating system.

# ICP OPTIONS
# -----------------------------------------------------------------------------

#  TAG: icp_port
#    The port number where Squid sends and receives ICP queries to
#    and from neighbor caches.  The standard UDP port for ICP is 3130.
#
#    Example:
#        icp_port 3130
#Default:
# ICP disabled.

#  TAG: htcp_port
#    The port number where Squid sends and receives HTCP queries to
#    and from neighbor caches.  To turn it on you want to set it to
#    4827.
#
#    Example:
#        htcp_port 4827
#Default:
# HTCP disabled.

#  TAG: log_icp_queries    on|off
#    If set, ICP queries are logged to access.log. You may wish
#    do disable this if your ICP load is VERY high to speed things
#    up or to simplify log analysis.
#Default:
# log_icp_queries on

#  TAG: udp_incoming_address
#    udp_incoming_address    is used for UDP packets received from other
#                caches.
#
#    The default behavior is to not bind to any specific address.
#
#    Only change this if you want to have all UDP queries received on
#    a specific interface/address.
#
#    NOTE: udp_incoming_address is used by the ICP, HTCP, and DNS
#    modules. Altering it will affect all of them in the same manner.
#
#    see also; udp_outgoing_address
#
#    NOTE, udp_incoming_address and udp_outgoing_address can not
#    have the same value since they both use the same port.
#Default:
# Accept packets from all machine interfaces.

#  TAG: udp_outgoing_address
#    udp_outgoing_address    is used for UDP packets sent out to other
#                caches.
#
#    The default behavior is to not bind to any specific address.
#
#    Instead it will use the same socket as udp_incoming_address.
#    Only change this if you want to have UDP queries sent using another
#    address than where this Squid listens for UDP queries from other
#    caches.
#
#    NOTE: udp_outgoing_address is used by the ICP, HTCP, and DNS
#    modules. Altering it will affect all of them in the same manner.
#
#    see also; udp_incoming_address
#
#    NOTE, udp_incoming_address and udp_outgoing_address can not
#    have the same value since they both use the same port.
#Default:
# Use udp_incoming_address or an address selected by the operating system.

#  TAG: icp_hit_stale    on|off
#    If you want to return ICP_HIT for stale cache objects, set this
#    option to 'on'.  If you have sibling relationships with caches
#    in other administrative domains, this should be 'off'.  If you only
#    have sibling relationships with caches under your control,
#    it is probably okay to set this to 'on'.
#    If set to 'on', your siblings should use the option "allow-miss"
#    on their cache_peer lines for connecting to you.
#Default:
# icp_hit_stale off

#  TAG: minimum_direct_hops
#    If using the ICMP pinging stuff, do direct fetches for sites
#    which are no more than this many hops away.
#Default:
# minimum_direct_hops 4

#  TAG: minimum_direct_rtt    (msec)
#    If using the ICMP pinging stuff, do direct fetches for sites
#    which are no more than this many rtt milliseconds away.
#Default:
# minimum_direct_rtt 400

#  TAG: netdb_low
#    The low water mark for the ICMP measurement database.
#
#    Note: high watermark controlled by netdb_high directive.
#
#    These watermarks are counts, not percents.  The defaults are
#    (low) 900 and (high) 1000.  When the high water mark is
#    reached, database entries will be deleted until the low
#    mark is reached.
#Default:
# netdb_low 900

#  TAG: netdb_high
#    The high water mark for the ICMP measurement database.
#
#    Note: low watermark controlled by netdb_low directive.
#
#    These watermarks are counts, not percents.  The defaults are
#    (low) 900 and (high) 1000.  When the high water mark is
#    reached, database entries will be deleted until the low
#    mark is reached.
#Default:
# netdb_high 1000

#  TAG: netdb_ping_period
#    The minimum period for measuring a site.  There will be at
#    least this much delay between successive pings to the same
#    network.  The default is five minutes.
#Default:
# netdb_ping_period 5 minutes

#  TAG: query_icmp    on|off
#    If you want to ask your peers to include ICMP data in their ICP
#    replies, enable this option.
#
#    If your peer has configured Squid (during compilation) with
#    '--enable-icmp' that peer will send ICMP pings to origin server
#    sites of the URLs it receives.  If you enable this option the
#    ICP replies from that peer will include the ICMP data (if available).
#    Then, when choosing a parent cache, Squid will choose the parent with
#    the minimal RTT to the origin server.  When this happens, the
#    hierarchy field of the access.log will be
#    "CLOSEST_PARENT_MISS".  This option is off by default.
#Default:
# query_icmp off

#  TAG: test_reachability    on|off
#    When this is 'on', ICP MISS replies will be ICP_MISS_NOFETCH
#    instead of ICP_MISS if the target host is NOT in the ICMP
#    database, or has a zero RTT.
#Default:
# test_reachability off

#  TAG: icp_query_timeout    (msec)
#    Normally Squid will automatically determine an optimal ICP
#    query timeout value based on the round-trip-time of recent ICP
#    queries.  If you want to override the value determined by
#    Squid, set this 'icp_query_timeout' to a non-zero value.  This
#    value is specified in MILLISECONDS, so, to use a 2-second
#    timeout (the old default), you would write:
#
#        icp_query_timeout 2000
#Default:
# Dynamic detection.

#  TAG: maximum_icp_query_timeout    (msec)
#    Normally the ICP query timeout is determined dynamically.  But
#    sometimes it can lead to very large values (say 5 seconds).
#    Use this option to put an upper limit on the dynamic timeout
#    value.  Do NOT use this option to always use a fixed (instead
#    of a dynamic) timeout value. To set a fixed timeout see the
#    'icp_query_timeout' directive.
#Default:
# maximum_icp_query_timeout 2000

#  TAG: minimum_icp_query_timeout    (msec)
#    Normally the ICP query timeout is determined dynamically.  But
#    sometimes it can lead to very small timeouts, even lower than
#    the normal latency variance on your link due to traffic.
#    Use this option to put an lower limit on the dynamic timeout
#    value.  Do NOT use this option to always use a fixed (instead
#    of a dynamic) timeout value. To set a fixed timeout see the
#    'icp_query_timeout' directive.
#Default:
# minimum_icp_query_timeout 5

#  TAG: background_ping_rate    time-units
#    Controls how often the ICP pings are sent to siblings that
#    have background-ping set.
#Default:
# background_ping_rate 10 seconds

# MULTICAST ICP OPTIONS
# -----------------------------------------------------------------------------

#  TAG: mcast_groups
#    This tag specifies a list of multicast groups which your server
#    should join to receive multicasted ICP queries.
#
#    NOTE!  Be very careful what you put here!  Be sure you
#    understand the difference between an ICP _query_ and an ICP
#    _reply_.  This option is to be set only if you want to RECEIVE
#    multicast queries.  Do NOT set this option to SEND multicast
#    ICP (use cache_peer for that).  ICP replies are always sent via
#    unicast, so this option does not affect whether or not you will
#    receive replies from multicast group members.
#
#    You must be very careful to NOT use a multicast address which
#    is already in use by another group of caches.
#
#    If you are unsure about multicast, please read the Multicast
#    chapter in the Squid FAQ (http://www.squid-cache.org/FAQ/).
#
#    Usage: mcast_groups 239.128.16.128 224.0.1.20
#
#    By default, Squid doesn't listen on any multicast groups.
#Default:
# none

#  TAG: mcast_miss_addr
# Note: This option is only available if Squid is rebuilt with the
#       -DMULTICAST_MISS_STREAM define
#
#    If you enable this option, every "cache miss" URL will
#    be sent out on the specified multicast address.
#
#    Do not enable this option unless you are are absolutely
#    certain you understand what you are doing.
#Default:
# disabled.

#  TAG: mcast_miss_ttl
# Note: This option is only available if Squid is rebuilt with the
#       -DMULTICAST_MISS_STREAM define
#
#    This is the time-to-live value for packets multicasted
#    when multicasting off cache miss URLs is enabled.  By
#    default this is set to 'site scope', i.e. 16.
#Default:
# mcast_miss_ttl 16

#  TAG: mcast_miss_port
# Note: This option is only available if Squid is rebuilt with the
#       -DMULTICAST_MISS_STREAM define
#
#    This is the port number to be used in conjunction with
#    'mcast_miss_addr'.
#Default:
# mcast_miss_port 3135

#  TAG: mcast_miss_encode_key
# Note: This option is only available if Squid is rebuilt with the
#       -DMULTICAST_MISS_STREAM define
#
#    The URLs that are sent in the multicast miss stream are
#    encrypted.  This is the encryption key.
#Default:
# mcast_miss_encode_key XXXXXXXXXXXXXXXX

#  TAG: mcast_icp_query_timeout    (msec)
#    For multicast peers, Squid regularly sends out ICP "probes" to
#    count how many other peers are listening on the given multicast
#    address.  This value specifies how long Squid should wait to
#    count all the replies.  The default is 2000 msec, or 2
#    seconds.
#Default:
# mcast_icp_query_timeout 2000

# INTERNAL ICON OPTIONS
# -----------------------------------------------------------------------------

#  TAG: icon_directory
#    Where the icons are stored. These are normally kept in
#    /usr/share/squid/icons
#Default:
# icon_directory /usr/share/squid/icons

#  TAG: global_internal_static
#    This directive controls is Squid should intercept all requests for
#    /squid-internal-static/ no matter which host the URL is requesting
#    (default on setting), or if nothing special should be done for
#    such URLs (off setting). The purpose of this directive is to make
#    icons etc work better in complex cache hierarchies where it may
#    not always be possible for all corners in the cache mesh to reach
#    the server generating a directory listing.
#Default:
# global_internal_static on

#  TAG: short_icon_urls
#    If this is enabled Squid will use short URLs for icons.
#    If disabled it will revert to the old behavior of including
#    it's own name and port in the URL.
#
#    If you run a complex cache hierarchy with a mix of Squid and
#    other proxies you may need to disable this directive.
#Default:
# short_icon_urls on

# ERROR PAGE OPTIONS
# -----------------------------------------------------------------------------

#  TAG: error_directory
#    If you wish to create your own versions of the default
#    error files to customize them to suit your company copy
#    the error/template files to another directory and point
#    this tag at them.
#
#    WARNING: This option will disable multi-language support
#             on error pages if used.
#
#    The squid developers are interested in making squid available in
#    a wide variety of languages. If you are making translations for a
#    language that Squid does not currently provide please consider
#    contributing your translation back to the project.
#    http://wiki.squid-cache.org/Translations
#
#    The squid developers working on translations are happy to supply drop-in
#    translated error files in exchange for any new language contributions.
#Default:
# Send error pages in the clients preferred language

#  TAG: error_default_language
#    Set the default language which squid will send error pages in
#    if no existing translation matches the clients language
#    preferences.
#
#    If unset (default) generic English will be used.
#
#    The squid developers are interested in making squid available in
#    a wide variety of languages. If you are interested in making
#    translations for any language see the squid wiki for details.
#    http://wiki.squid-cache.org/Translations
#Default:
# Generate English language pages.

#  TAG: error_log_languages
#    Log to cache.log what languages users are attempting to
#    auto-negotiate for translations.
#
#    Successful negotiations are not logged. Only failures
#    have meaning to indicate that Squid may need an upgrade
#    of its error page translations.
#Default:
# error_log_languages on

#  TAG: err_page_stylesheet
#    CSS Stylesheet to pattern the display of Squid default error pages.
#
#    For information on CSS see http://www.w3.org/Style/CSS/
#Default:
# err_page_stylesheet /etc/squid/errorpage.css

#  TAG: err_html_text
#    HTML text to include in error messages.  Make this a "mailto"
#    URL to your admin address, or maybe just a link to your
#    organizations Web page.
#
#    To include this in your error messages, you must rewrite
#    the error template files (found in the "errors" directory).
#    Wherever you want the 'err_html_text' line to appear,
#    insert a %L tag in the error template file.
#Default:
# none

#  TAG: email_err_data    on|off
#    If enabled, information about the occurred error will be
#    included in the mailto links of the ERR pages (if %W is set)
#    so that the email body contains the data.
#    Syntax is <A HREF="mailto:%w%W">%w</A>
#Default:
# email_err_data on

#  TAG: deny_info
#    Usage:   deny_info err_page_name acl
#    or       deny_info http://... acl
#    or       deny_info TCP_RESET acl
#
#    This can be used to return a ERR_ page for requests which
#    do not pass the 'http_access' rules.  Squid remembers the last
#    acl it evaluated in http_access, and if a 'deny_info' line exists
#    for that ACL Squid returns a corresponding error page.
#
#    The acl is typically the last acl on the http_access deny line which
#    denied access. The exceptions to this rule are:
#    - When Squid needs to request authentication credentials. It's then
#      the first authentication related acl encountered
#    - When none of the http_access lines matches. It's then the last
#      acl processed on the last http_access line.
#    - When the decision to deny access was made by an adaptation service,
#      the acl name is the corresponding eCAP or ICAP service_name.
#
#    NP: If providing your own custom error pages with error_directory
#        you may also specify them by your custom file name:
#        Example: deny_info ERR_CUSTOM_ACCESS_DENIED bad_guys
#
#    By defaut Squid will send "403 Forbidden". A different 4xx or 5xx
#    may be specified by prefixing the file name with the code and a colon.
#    e.g. 404:ERR_CUSTOM_ACCESS_DENIED
#
#    Alternatively you can tell Squid to reset the TCP connection
#    by specifying TCP_RESET.
#
#    Or you can specify an error URL or URL pattern. The browsers will
#    get redirected to the specified URL after formatting tags have
#    been replaced. Redirect will be done with 302 or 307 according to
#    HTTP/1.1 specs. A different 3xx code may be specified by prefixing
#    the URL. e.g. 303:http://example.com/
#
#    URL FORMAT TAGS:
#        %a    - username (if available. Password NOT included)
#        %A    - Local listening IP address the client connection was connected to
#        %B    - FTP path URL
#        %e    - Error number
#        %E    - Error description
#        %h    - Squid hostname
#        %H    - Request domain name
#        %i    - Client IP Address
#        %M    - Request Method
#        %O    - Unescaped message result from external ACL helper
#        %o    - Message result from external ACL helper
#        %p    - Request Port number
#        %P    - Request Protocol name
#        %R    - Request URL path
#        %T    - Timestamp in RFC 1123 format
#        %U    - Full canonical URL from client
#              (HTTPS URLs terminate with *)
#        %u    - Full canonical URL from client
#        %w    - Admin email from squid.conf
#        %x    - Error name
#        %%    - Literal percent (%) code
#
#Default:
# none

# OPTIONS INFLUENCING REQUEST FORWARDING
# -----------------------------------------------------------------------------

#  TAG: nonhierarchical_direct
#    By default, Squid will send any non-hierarchical requests
#    (not cacheable request type) direct to origin servers.
#
#    When this is set to "off", Squid will prefer to send these
#    requests to parents.
#
#    Note that in most configurations, by turning this off you will only
#    add latency to these request without any improvement in global hit
#    ratio.
#
#    This option only sets a preference. If the parent is unavailable a
#    direct connection to the origin server may still be attempted. To
#    completely prevent direct connections use never_direct.
#Default:
# nonhierarchical_direct on

#  TAG: prefer_direct
#    Normally Squid tries to use parents for most requests. If you for some
#    reason like it to first try going direct and only use a parent if
#    going direct fails set this to on.
#
#    By combining nonhierarchical_direct off and prefer_direct on you
#    can set up Squid to use a parent as a backup path if going direct
#    fails.
#
#    Note: If you want Squid to use parents for all requests see
#    the never_direct directive. prefer_direct only modifies how Squid
#    acts on cacheable requests.
#Default:
# prefer_direct off

#  TAG: cache_miss_revalidate    on|off
#    RFC 7232 defines a conditional request mechanism to prevent
#    response objects being unnecessarily transferred over the network.
#    If that mechanism is used by the client and a cache MISS occurs
#    it can prevent new cache entries being created.
#
#    This option determines whether Squid on cache MISS will pass the
#    client revalidation request to the server or tries to fetch new
#    content for caching. It can be useful while the cache is mostly
#    empty to more quickly have the cache populated by generating
#    non-conditional GETs.
#
#    When set to 'on' (default), Squid will pass all client If-* headers
#    to the server. This permits server responses without a cacheable
#    payload to be delivered and on MISS no new cache entry is created.
#
#    When set to 'off' and if the request is cacheable, Squid will
#    remove the clients If-Modified-Since and If-None-Match headers from
#    the request sent to the server. This requests a 200 status response
#    from the server to create a new cache entry with.
#Default:
# cache_miss_revalidate on

#  TAG: always_direct
#    Usage: always_direct allow|deny [!]aclname ...
#
#    Here you can use ACL elements to specify requests which should
#    ALWAYS be forwarded by Squid to the origin servers without using
#    any peers.  For example, to always directly forward requests for
#    local servers ignoring any parents or siblings you may have use
#    something like:
#
#        acl local-servers dstdomain my.domain.net
#        always_direct allow local-servers
#
#    To always forward FTP requests directly, use
#
#        acl FTP proto FTP
#        always_direct allow FTP
#
#    NOTE: There is a similar, but opposite option named
#    'never_direct'.  You need to be aware that "always_direct deny
#    foo" is NOT the same thing as "never_direct allow foo".  You
#    may need to use a deny rule to exclude a more-specific case of
#    some other rule.  Example:
#
#        acl local-external dstdomain external.foo.net
#        acl local-servers dstdomain  .foo.net
#        always_direct deny local-external
#        always_direct allow local-servers
#
#    NOTE: If your goal is to make the client forward the request
#    directly to the origin server bypassing Squid then this needs
#    to be done in the client configuration. Squid configuration
#    can only tell Squid how Squid should fetch the object.
#
#    NOTE: This directive is not related to caching. The replies
#    is cached as usual even if you use always_direct. To not cache
#    the replies see the 'cache' directive.
#
#    This clause supports both fast and slow acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#Default:
# Prevent any cache_peer being used for this request.

#  TAG: never_direct
#    Usage: never_direct allow|deny [!]aclname ...
#
#    never_direct is the opposite of always_direct.  Please read
#    the description for always_direct if you have not already.
#
#    With 'never_direct' you can use ACL elements to specify
#    requests which should NEVER be forwarded directly to origin
#    servers.  For example, to force the use of a proxy for all
#    requests, except those in your local domain use something like:
#
#        acl local-servers dstdomain .foo.net
#        never_direct deny local-servers
#        never_direct allow all
#
#    or if Squid is inside a firewall and there are local intranet
#    servers inside the firewall use something like:
#
#        acl local-intranet dstdomain .foo.net
#        acl local-external dstdomain external.foo.net
#        always_direct deny local-external
#        always_direct allow local-intranet
#        never_direct allow all
#
#    This clause supports both fast and slow acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#Default:
# Allow DNS results to be used for this request.

# ADVANCED NETWORKING OPTIONS
# -----------------------------------------------------------------------------

#  TAG: incoming_udp_average
#    Heavy voodoo here.  I can't even believe you are reading this.
#    Are you crazy?  Don't even think about adjusting these unless
#    you understand the algorithms in comm_select.c first!
#Default:
# incoming_udp_average 6

#  TAG: incoming_tcp_average
#    Heavy voodoo here.  I can't even believe you are reading this.
#    Are you crazy?  Don't even think about adjusting these unless
#    you understand the algorithms in comm_select.c first!
#Default:
# incoming_tcp_average 4

#  TAG: incoming_dns_average
#    Heavy voodoo here.  I can't even believe you are reading this.
#    Are you crazy?  Don't even think about adjusting these unless
#    you understand the algorithms in comm_select.c first!
#Default:
# incoming_dns_average 4

#  TAG: min_udp_poll_cnt
#    Heavy voodoo here.  I can't even believe you are reading this.
#    Are you crazy?  Don't even think about adjusting these unless
#    you understand the algorithms in comm_select.c first!
#Default:
# min_udp_poll_cnt 8

#  TAG: min_dns_poll_cnt
#    Heavy voodoo here.  I can't even believe you are reading this.
#    Are you crazy?  Don't even think about adjusting these unless
#    you understand the algorithms in comm_select.c first!
#Default:
# min_dns_poll_cnt 8

#  TAG: min_tcp_poll_cnt
#    Heavy voodoo here.  I can't even believe you are reading this.
#    Are you crazy?  Don't even think about adjusting these unless
#    you understand the algorithms in comm_select.c first!
#Default:
# min_tcp_poll_cnt 8

#  TAG: accept_filter
#    FreeBSD:
#
#    The name of an accept(2) filter to install on Squid's
#    listen socket(s).  This feature is perhaps specific to
#    FreeBSD and requires support in the kernel.
#
#    The 'httpready' filter delays delivering new connections
#    to Squid until a full HTTP request has been received.
#    See the accf_http(9) man page for details.
#
#    The 'dataready' filter delays delivering new connections
#    to Squid until there is some data to process.
#    See the accf_dataready(9) man page for details.
#
#    Linux:
#
#    The 'data' filter delays delivering of new connections
#    to Squid until there is some data to process by TCP_ACCEPT_DEFER.
#    You may optionally specify a number of seconds to wait by
#    'data=N' where N is the number of seconds. Defaults to 30
#    if not specified.  See the tcp(7) man page for details.
#EXAMPLE:
## FreeBSD
#accept_filter httpready
## Linux
#accept_filter data
#Default:
# none

#  TAG: client_ip_max_connections
#    Set an absolute limit on the number of connections a single
#    client IP can use. Any more than this and Squid will begin to drop
#    new connections from the client until it closes some links.
#
#    Note that this is a global limit. It affects all HTTP, HTCP, Gopher and FTP
#    connections from the client. For finer control use the ACL access controls.
#
#    Requires client_db to be enabled (the default).
#
#    WARNING: This may noticably slow down traffic received via external proxies
#    or NAT devices and cause them to rebound error messages back to their clients.
#Default:
# No limit.

#  TAG: tcp_recv_bufsize    (bytes)
#    Size of receive buffer to set for TCP sockets.  Probably just
#    as easy to change your kernel's default.
#    Omit from squid.conf to use the default buffer size.
#Default:
# Use operating system TCP defaults.

# ICAP OPTIONS
# -----------------------------------------------------------------------------

#  TAG: icap_enable    on|off
#    If you want to enable the ICAP module support, set this to on.
#Default:
# icap_enable off

#  TAG: icap_connect_timeout
#    This parameter specifies how long to wait for the TCP connect to
#    the requested ICAP server to complete before giving up and either
#    terminating the HTTP transaction or bypassing the failure.
#
#    The default for optional services is peer_connect_timeout.
#    The default for essential services is connect_timeout.
#    If this option is explicitly set, its value applies to all services.
#Default:
# none

#  TAG: icap_io_timeout    time-units
#    This parameter specifies how long to wait for an I/O activity on
#    an established, active ICAP connection before giving up and
#    either terminating the HTTP transaction or bypassing the
#    failure.
#Default:
# Use read_timeout.

#  TAG: icap_service_failure_limit    limit [in memory-depth time-units]
#    The limit specifies the number of failures that Squid tolerates
#    when establishing a new TCP connection with an ICAP service. If
#    the number of failures exceeds the limit, the ICAP service is
#    not used for new ICAP requests until it is time to refresh its
#    OPTIONS.
#
#    A negative value disables the limit. Without the limit, an ICAP
#    service will not be considered down due to connectivity failures
#    between ICAP OPTIONS requests.
#
#    Squid forgets ICAP service failures older than the specified
#    value of memory-depth. The memory fading algorithm
#    is approximate because Squid does not remember individual
#    errors but groups them instead, splitting the option
#    value into ten time slots of equal length.
#
#    When memory-depth is 0 and by default this option has no
#    effect on service failure expiration.
#
#    Squid always forgets failures when updating service settings
#    using an ICAP OPTIONS transaction, regardless of this option
#    setting.
#
#    For example,
#        # suspend service usage after 10 failures in 5 seconds:
#        icap_service_failure_limit 10 in 5 seconds
#Default:
# icap_service_failure_limit 10

#  TAG: icap_service_revival_delay
#    The delay specifies the number of seconds to wait after an ICAP
#    OPTIONS request failure before requesting the options again. The
#    failed ICAP service is considered "down" until fresh OPTIONS are
#    fetched.
#
#    The actual delay cannot be smaller than the hardcoded minimum
#    delay of 30 seconds.
#Default:
# icap_service_revival_delay 180

#  TAG: icap_preview_enable    on|off
#    The ICAP Preview feature allows the ICAP server to handle the
#    HTTP message by looking only at the beginning of the message body
#    or even without receiving the body at all. In some environments,
#    previews greatly speedup ICAP processing.
#
#    During an ICAP OPTIONS transaction, the server may tell    Squid what
#    HTTP messages should be previewed and how big the preview should be.
#    Squid will not use Preview if the server did not request one.
#
#    To disable ICAP Preview for all ICAP services, regardless of
#    individual ICAP server OPTIONS responses, set this option to "off".
#Example:
#icap_preview_enable off
#Default:
# icap_preview_enable on

#  TAG: icap_preview_size
#    The default size of preview data to be sent to the ICAP server.
#    This value might be overwritten on a per server basis by OPTIONS requests.
#Default:
# No preview sent.

#  TAG: icap_206_enable    on|off
#    206 (Partial Content) responses is an ICAP extension that allows the
#    ICAP agents to optionally combine adapted and original HTTP message
#    content. The decision to combine is postponed until the end of the
#    ICAP response. Squid supports Partial Content extension by default.
#
#    Activation of the Partial Content extension is negotiated with each
#    ICAP service during OPTIONS exchange. Most ICAP servers should handle
#    negotation correctly even if they do not support the extension, but
#    some might fail. To disable Partial Content support for all ICAP
#    services and to avoid any negotiation, set this option to "off".
#
#    Example:
#        icap_206_enable off
#Default:
# icap_206_enable on

#  TAG: icap_default_options_ttl
#    The default TTL value for ICAP OPTIONS responses that don't have
#    an Options-TTL header.
#Default:
# icap_default_options_ttl 60

#  TAG: icap_persistent_connections    on|off
#    Whether or not Squid should use persistent connections to
#    an ICAP server.
#Default:
# icap_persistent_connections on

#  TAG: adaptation_send_client_ip    on|off
#    If enabled, Squid shares HTTP client IP information with adaptation
#    services. For ICAP, Squid adds the X-Client-IP header to ICAP requests.
#    For eCAP, Squid sets the libecap::metaClientIp transaction option.
#
#    See also: adaptation_uses_indirect_client
#Default:
# adaptation_send_client_ip off

#  TAG: adaptation_send_username    on|off
#    This sends authenticated HTTP client username (if available) to
#    the adaptation service.
#
#    For ICAP, the username value is encoded based on the
#    icap_client_username_encode option and is sent using the header
#    specified by the icap_client_username_header option.
#Default:
# adaptation_send_username off

#  TAG: icap_client_username_header
#    ICAP request header name to use for adaptation_send_username.
#Default:
# icap_client_username_header X-Client-Username

#  TAG: icap_client_username_encode    on|off
#    Whether to base64 encode the authenticated client username.
#Default:
# icap_client_username_encode off

#  TAG: icap_service
#    Defines a single ICAP service using the following format:
#
#    icap_service id vectoring_point uri [option ...]
#
#    id: ID
#        an opaque identifier or name which is used to direct traffic to
#        this specific service. Must be unique among all adaptation
#        services in squid.conf.
#
#    vectoring_point: reqmod_precache|reqmod_postcache|respmod_precache|respmod_postcache
#        This specifies at which point of transaction processing the
#        ICAP service should be activated. *_postcache vectoring points
#        are not yet supported.
#
#    uri: icap://servername:port/servicepath
#        ICAP server and service location.
#         icaps://servername:port/servicepath
#        The "icap:" URI scheme is used for traditional ICAP server and
#        service location (default port is 1344, connections are not
#        encrypted). The "icaps:" URI scheme is for Secure ICAP
#        services that use SSL/TLS-encrypted ICAP connections (by
#        default, on port 11344).
#
#    ICAP does not allow a single service to handle both REQMOD and RESPMOD
#    transactions. Squid does not enforce that requirement. You can specify
#    services with the same service_url and different vectoring_points. You
#    can even specify multiple identical services as long as their
#    service_names differ.
#
#    To activate a service, use the adaptation_access directive. To group
#    services, use adaptation_service_chain and adaptation_service_set.
#
#    Service options are separated by white space. ICAP services support
#    the following name=value options:
#
#    bypass=on|off|1|0
#        If set to 'on' or '1', the ICAP service is treated as
#        optional. If the service cannot be reached or malfunctions,
#        Squid will try to ignore any errors and process the message as
#        if the service was not enabled. No all ICAP errors can be
#        bypassed.  If set to 0, the ICAP service is treated as
#        essential and all ICAP errors will result in an error page
#        returned to the HTTP client.
#
#        Bypass is off by default: services are treated as essential.
#
#    routing=on|off|1|0
#        If set to 'on' or '1', the ICAP service is allowed to
#        dynamically change the current message adaptation plan by
#        returning a chain of services to be used next. The services
#        are specified using the X-Next-Services ICAP response header
#        value, formatted as a comma-separated list of service names.
#        Each named service should be configured in squid.conf. Other
#        services are ignored. An empty X-Next-Services value results
#        in an empty plan which ends the current adaptation.
#
#        Dynamic adaptation plan may cross or cover multiple supported
#        vectoring points in their natural processing order.
#
#        Routing is not allowed by default: the ICAP X-Next-Services
#        response header is ignored.
#
#    ipv6=on|off
#        Only has effect on split-stack systems. The default on those systems
#        is to use IPv4-only connections. When set to 'on' this option will
#        make Squid use IPv6-only connections to contact this ICAP service.
#
#    on-overload=block|bypass|wait|force
#        If the service Max-Connections limit has been reached, do
#        one of the following for each new ICAP transaction:
#          * block:  send an HTTP error response to the client
#          * bypass: ignore the "over-connected" ICAP service
#          * wait:   wait (in a FIFO queue) for an ICAP connection slot
#          * force:  proceed, ignoring the Max-Connections limit
#
#        In SMP mode with N workers, each worker assumes the service
#        connection limit is Max-Connections/N, even though not all
#        workers may use a given service.
#
#        The default value is "bypass" if service is bypassable,
#        otherwise it is set to "wait".
#
#
#    max-conn=number
#        Use the given number as the Max-Connections limit, regardless
#        of the Max-Connections value given by the service, if any.
#
#    connection-encryption=on|off
#        Determines the ICAP service effect on the connections_encrypted
#        ACL.
#
#        The default is "on" for Secure ICAP services (i.e., those
#        with the icaps:// service URIs scheme) and "off" for plain ICAP
#        services.
#
#        Does not affect ICAP connections (e.g., does not turn Secure
#        ICAP on or off).
#
#    ==== ICAPS / TLS OPTIONS ====
#
#    These options are used for Secure ICAP (icaps://....) services only.
#
#    tls-cert=/path/to/ssl/certificate
#            A client X.509 certificate to use when connecting to
#            this ICAP server.
#
#    tls-key=/path/to/ssl/key
#            The private key corresponding to the previous
#            tls-cert= option.
#
#            If tls-key= is not specified tls-cert= is assumed to
#            reference a PEM file containing both the certificate
#            and private key.
#
#    tls-cipher=...    The list of valid TLS/SSL ciphers to use when connecting
#            to this icap server.
#
#    tls-min-version=1.N
#            The minimum TLS protocol version to permit. To control
#            SSLv3 use the tls-options= parameter.
#            Supported Values: 1.0 (default), 1.1, 1.2
#
#    tls-options=...    Specify various OpenSSL library options:
#
#                NO_SSLv3    Disallow the use of SSLv3
#
#                SINGLE_DH_USE
#                      Always create a new key when using
#                      temporary/ephemeral DH key exchanges
#
#                ALL       Enable various bug workarounds
#                      suggested as "harmless" by OpenSSL
#                      Be warned that this reduces SSL/TLS
#                      strength to some attacks.
#
#            See the OpenSSL SSL_CTX_set_options documentation for a
#            more complete list. Options relevant only to SSLv2 are
#            not supported.
#
#    tls-cafile=    PEM file containing CA certificates to use when verifying
#            the icap server certificate.
#            Use to specify intermediate CA certificate(s) if not sent
#            by the server. Or the full CA chain for the server when
#            using the tls-default-ca=off flag.
#            May be repeated to load multiple files.
#
#    tls-capath=...    A directory containing additional CA certificates to
#            use when verifying the icap server certificate.
#            Requires OpenSSL or LibreSSL.
#
#    tls-crlfile=...    A certificate revocation list file to use when
#            verifying the icap server certificate.
#
#    tls-flags=...    Specify various flags modifying the Squid TLS implementation:
#
#            DONT_VERIFY_PEER
#                Accept certificates even if they fail to
#                verify.
#            DONT_VERIFY_DOMAIN
#                Don't verify the icap server certificate
#                matches the server name
#
#    tls-default-ca[=off]
#            Whether to use the system Trusted CAs. Default is ON.
#
#    tls-domain=    The icap server name as advertised in it's certificate.
#            Used for verifying the correctness of the received icap
#            server certificate. If not specified the icap server
#            hostname extracted from ICAP URI will be used.
#
#    Older icap_service format without optional named parameters is
#    deprecated but supported for backward compatibility.
#
#Example:
#icap_service svcBlocker reqmod_precache icap://icap1.mydomain.net:1344/reqmod bypass=0
#icap_service svcLogger reqmod_precache icaps://icap2.mydomain.net:11344/reqmod routing=on
#Default:
# none

#  TAG: icap_class
#    This deprecated option was documented to define an ICAP service
#    chain, even though it actually defined a set of similar, redundant
#    services, and the chains were not supported.
#
#    To define a set of redundant services, please use the
#    adaptation_service_set directive. For service chains, use
#    adaptation_service_chain.
#Default:
# none

#  TAG: icap_access
#    This option is deprecated. Please use adaptation_access, which
#    has the same ICAP functionality, but comes with better
#    documentation, and eCAP support.
#Default:
# none

# eCAP OPTIONS
# -----------------------------------------------------------------------------

#  TAG: ecap_enable    on|off
#    Controls whether eCAP support is enabled.
#Default:
# ecap_enable off

#  TAG: ecap_service
#    Defines a single eCAP service
#
#    ecap_service id vectoring_point uri [option ...]
#
#        id: ID
#        an opaque identifier or name which is used to direct traffic to
#        this specific service. Must be unique among all adaptation
#        services in squid.conf.
#
#    vectoring_point: reqmod_precache|reqmod_postcache|respmod_precache|respmod_postcache
#        This specifies at which point of transaction processing the
#        eCAP service should be activated. *_postcache vectoring points
#        are not yet supported.
#
#    uri: ecap://vendor/service_name?custom&cgi=style&parameters=optional
#        Squid uses the eCAP service URI to match this configuration
#        line with one of the dynamically loaded services. Each loaded
#        eCAP service must have a unique URI. Obtain the right URI from
#        the service provider.
#
#    To activate a service, use the adaptation_access directive. To group
#    services, use adaptation_service_chain and adaptation_service_set.
#
#    Service options are separated by white space. eCAP services support
#    the following name=value options:
#
#    bypass=on|off|1|0
#        If set to 'on' or '1', the eCAP service is treated as optional.
#        If the service cannot be reached or malfunctions, Squid will try
#        to ignore any errors and process the message as if the service
#        was not enabled. No all eCAP errors can be bypassed.
#        If set to 'off' or '0', the eCAP service is treated as essential
#        and all eCAP errors will result in an error page returned to the
#        HTTP client.
#
#                Bypass is off by default: services are treated as essential.
#
#    routing=on|off|1|0
#        If set to 'on' or '1', the eCAP service is allowed to
#        dynamically change the current message adaptation plan by
#        returning a chain of services to be used next.
#
#        Dynamic adaptation plan may cross or cover multiple supported
#        vectoring points in their natural processing order.
#
#        Routing is not allowed by default.
#
#    connection-encryption=on|off
#        Determines the eCAP service effect on the connections_encrypted
#        ACL.
#
#        Defaults to "on", which does not taint the master transaction
#        w.r.t. that ACL.
#
#        Does not affect eCAP API calls.
#
#    Older ecap_service format without optional named parameters is
#    deprecated but supported for backward compatibility.
#
#
#Example:
#ecap_service s1 reqmod_precache ecap://filters.R.us/leakDetector?on_error=block bypass=off
#ecap_service s2 respmod_precache ecap://filters.R.us/virusFilter config=/etc/vf.cfg bypass=on
#Default:
# none

#  TAG: loadable_modules
#    Instructs Squid to load the specified dynamic module(s) or activate
#    preloaded module(s).
#Example:
#loadable_modules /usr/lib/MinimalAdapter.so
#Default:
# none

# MESSAGE ADAPTATION OPTIONS
# -----------------------------------------------------------------------------

#  TAG: adaptation_service_set
#
#    Configures an ordered set of similar, redundant services. This is
#    useful when hot standby or backup adaptation servers are available.
#
#        adaptation_service_set set_name service_name1 service_name2 ...
#
#     The named services are used in the set declaration order. The first
#    applicable adaptation service from the set is used first. The next
#    applicable service is tried if and only if the transaction with the
#    previous service fails and the message waiting to be adapted is still
#    intact.
#
#    When adaptation starts, broken services are ignored as if they were
#    not a part of the set. A broken service is a down optional service.
#
#    The services in a set must be attached to the same vectoring point
#    (e.g., pre-cache) and use the same adaptation method (e.g., REQMOD).
#
#    If all services in a set are optional then adaptation failures are
#    bypassable. If all services in the set are essential, then a
#    transaction failure with one service may still be retried using
#    another service from the set, but when all services fail, the master
#    transaction fails as well.
#
#    A set may contain a mix of optional and essential services, but that
#    is likely to lead to surprising results because broken services become
#    ignored (see above), making previously bypassable failures fatal.
#    Technically, it is the bypassability of the last failed service that
#    matters.
#
#    See also: adaptation_access adaptation_service_chain
#
#Example:
#adaptation_service_set svcBlocker urlFilterPrimary urlFilterBackup
#adaptation service_set svcLogger loggerLocal loggerRemote
#Default:
# none

#  TAG: adaptation_service_chain
#
#    Configures a list of complementary services that will be applied
#    one-by-one, forming an adaptation chain or pipeline. This is useful
#    when Squid must perform different adaptations on the same message.
#
#        adaptation_service_chain chain_name service_name1 svc_name2 ...
#
#     The named services are used in the chain declaration order. The first
#    applicable adaptation service from the chain is used first. The next
#    applicable service is applied to the successful adaptation results of
#    the previous service in the chain.
#
#    When adaptation starts, broken services are ignored as if they were
#    not a part of the chain. A broken service is a down optional service.
#
#    Request satisfaction terminates the adaptation chain because Squid
#    does not currently allow declaration of RESPMOD services at the
#    "reqmod_precache" vectoring point (see icap_service or ecap_service).
#
#    The services in a chain must be attached to the same vectoring point
#    (e.g., pre-cache) and use the same adaptation method (e.g., REQMOD).
#
#    A chain may contain a mix of optional and essential services. If an
#    essential adaptation fails (or the failure cannot be bypassed for
#    other reasons), the master transaction fails. Otherwise, the failure
#    is bypassed as if the failed adaptation service was not in the chain.
#
#    See also: adaptation_access adaptation_service_set
#
#Example:
#adaptation_service_chain svcRequest requestLogger urlFilter leakDetector
#Default:
# none

#  TAG: adaptation_access
#    Sends an HTTP transaction to an ICAP or eCAP adaptation    service.
#
#    adaptation_access service_name allow|deny [!]aclname...
#    adaptation_access set_name     allow|deny [!]aclname...
#
#    At each supported vectoring point, the adaptation_access
#    statements are processed in the order they appear in this
#    configuration file. Statements pointing to the following services
#    are ignored (i.e., skipped without checking their ACL):
#
#        - services serving different vectoring points
#        - "broken-but-bypassable" services
#        - "up" services configured to ignore such transactions
#              (e.g., based on the ICAP Transfer-Ignore header).
#
#        When a set_name is used, all services in the set are checked
#    using the same rules, to find the first applicable one. See
#    adaptation_service_set for details.
#
#    If an access list is checked and there is a match, the
#    processing stops: For an "allow" rule, the corresponding
#    adaptation service is used for the transaction. For a "deny"
#    rule, no adaptation service is activated.
#
#    It is currently not possible to apply more than one adaptation
#    service at the same vectoring point to the same HTTP transaction.
#
#        See also: icap_service and ecap_service
#
#Example:
#adaptation_access service_1 allow all
#Default:
# Allow, unless rules exist in squid.conf.

#  TAG: adaptation_service_iteration_limit
#    Limits the number of iterations allowed when applying adaptation
#    services to a message. If your longest adaptation set or chain
#    may have more than 16 services, increase the limit beyond its
#    default value of 16. If detecting infinite iteration loops sooner
#    is critical, make the iteration limit match the actual number
#    of services in your longest adaptation set or chain.
#
#    Infinite adaptation loops are most likely with routing services.
#
#    See also: icap_service routing=1
#Default:
# adaptation_service_iteration_limit 16

#  TAG: adaptation_masterx_shared_names
#    For each master transaction (i.e., the HTTP request and response
#    sequence, including all related ICAP and eCAP exchanges), Squid
#    maintains a table of metadata. The table entries are (name, value)
#    pairs shared among eCAP and ICAP exchanges. The table is destroyed
#    with the master transaction.
#
#    This option specifies the table entry names that Squid must accept
#    from and forward to the adaptation transactions.
#
#    An ICAP REQMOD or RESPMOD transaction may set an entry in the
#    shared table by returning an ICAP header field with a name
#    specified in adaptation_masterx_shared_names.
#
#    An eCAP REQMOD or RESPMOD transaction may set an entry in the
#    shared table by implementing the libecap::visitEachOption() API
#    to provide an option with a name specified in
#    adaptation_masterx_shared_names.
#
#    Squid will store and forward the set entry to subsequent adaptation
#    transactions within the same master transaction scope.
#
#    Only one shared entry name is supported at this time.
#
#Example:
## share authentication information among ICAP services
#adaptation_masterx_shared_names X-Subscriber-ID
#Default:
# none

#  TAG: adaptation_meta
#    This option allows Squid administrator to add custom ICAP request
#    headers or eCAP options to Squid ICAP requests or eCAP transactions.
#    Use it to pass custom authentication tokens and other
#    transaction-state related meta information to an ICAP/eCAP service.
#
#    The addition of a meta header is ACL-driven:
#        adaptation_meta name value [!]aclname ...
#
#    Processing for a given header name stops after the first ACL list match.
#    Thus, it is impossible to add two headers with the same name. If no ACL
#    lists match for a given header name, no such header is added. For
#    example:
#
#        # do not debug transactions except for those that need debugging
#        adaptation_meta X-Debug 1 needs_debugging
#
#        # log all transactions except for those that must remain secret
#        adaptation_meta X-Log 1 !keep_secret
#
#        # mark transactions from users in the "G 1" group
#        adaptation_meta X-Authenticated-Groups "G 1" authed_as_G1
#
#    The "value" parameter may be a regular squid.conf token or a "double
#    quoted string". Within the quoted string, use backslash (\) to escape
#    any character, which is currently only useful for escaping backslashes
#    and double quotes. For example,
#        "this string has one backslash (\\) and two \"quotes\""
#
#    Used adaptation_meta header values may be logged via %note
#    logformat code. If multiple adaptation_meta headers with the same name
#    are used during master transaction lifetime, the header values are
#    logged in the order they were used and duplicate values are ignored
#    (only the first repeated value will be logged).
#Default:
# none

#  TAG: icap_retry
#    This ACL determines which retriable ICAP transactions are
#    retried. Transactions that received a complete ICAP response
#    and did not have to consume or produce HTTP bodies to receive
#    that response are usually retriable.
#
#    icap_retry allow|deny [!]aclname ...
#
#    Squid automatically retries some ICAP I/O timeouts and errors
#    due to persistent connection race conditions.
#
#    See also: icap_retry_limit
#Default:
# icap_retry deny all

#  TAG: icap_retry_limit
#    Limits the number of retries allowed.
#
#    Communication errors due to persistent connection race
#    conditions are unavoidable, automatically retried, and do not
#    count against this limit.
#
#    See also: icap_retry
#Default:
# No retries are allowed.

# DNS OPTIONS
# -----------------------------------------------------------------------------

#  TAG: check_hostnames
#    For security and stability reasons Squid can check
#    hostnames for Internet standard RFC compliance. If you want
#    Squid to perform these checks turn this directive on.
#Default:
# check_hostnames off

#  TAG: allow_underscore
#    Underscore characters is not strictly allowed in Internet hostnames
#    but nevertheless used by many sites. Set this to off if you want
#    Squid to be strict about the standard.
#    This check is performed only when check_hostnames is set to on.
#Default:
# allow_underscore on

#  TAG: dns_retransmit_interval
#    Initial retransmit interval for DNS queries. The interval is
#    doubled each time all configured DNS servers have been tried.
#Default:
# dns_retransmit_interval 5 seconds

#  TAG: dns_timeout
#    DNS Query timeout. If no response is received to a DNS query
#    within this time all DNS servers for the queried domain
#    are assumed to be unavailable.
#Default:
# dns_timeout 30 seconds

#  TAG: dns_packet_max
#    Maximum number of bytes packet size to advertise via EDNS.
#    Set to "none" to disable EDNS large packet support.
#
#    For legacy reasons DNS UDP replies will default to 512 bytes which
#    is too small for many responses. EDNS provides a means for Squid to
#    negotiate receiving larger responses back immediately without having
#    to failover with repeat requests. Responses larger than this limit
#    will retain the old behaviour of failover to TCP DNS.
#
#    Squid has no real fixed limit internally, but allowing packet sizes
#    over 1500 bytes requires network jumbogram support and is usually not
#    necessary.
#
#    WARNING: The RFC also indicates that some older resolvers will reply
#    with failure of the whole request if the extension is added. Some
#    resolvers have already been identified which will reply with mangled
#    EDNS response on occasion. Usually in response to many-KB jumbogram
#    sizes being advertised by Squid.
#    Squid will currently treat these both as an unable-to-resolve domain
#    even if it would be resolvable without EDNS.
#Default:
# EDNS disabled

#  TAG: dns_defnames    on|off
#    Normally the RES_DEFNAMES resolver option is disabled
#    (see res_init(3)).  This prevents caches in a hierarchy
#    from interpreting single-component hostnames locally.  To allow
#    Squid to handle single-component names, enable this option.
#Default:
# Search for single-label domain names is disabled.

#  TAG: dns_multicast_local    on|off
#    When set to on, Squid sends multicast DNS lookups on the local
#    network for domains ending in .local and .arpa.
#    This enables local servers and devices to be contacted in an
#    ad-hoc or zero-configuration network environment.
#Default:
# Search for .local and .arpa names is disabled.

#  TAG: dns_nameservers
#    Use this if you want to specify a list of DNS name servers
#    (IP addresses) to use instead of those given in your
#    /etc/resolv.conf file.
#
#    On Windows platforms, if no value is specified here or in
#    the /etc/resolv.conf file, the list of DNS name servers are
#    taken from the Windows registry, both static and dynamic DHCP
#    configurations are supported.
#
#    Example: dns_nameservers 10.0.0.1 192.172.0.4
#Default:
# Use operating system definitions

#  TAG: hosts_file
#    Location of the host-local IP name-address associations
#    database. Most Operating Systems have such a file on different
#    default locations:
#    - Un*X & Linux:    /etc/hosts
#    - Windows NT/2000: %SystemRoot%\system32\drivers\etc\hosts
#               (%SystemRoot% value install default is c:\winnt)
#    - Windows XP/2003: %SystemRoot%\system32\drivers\etc\hosts
#               (%SystemRoot% value install default is c:\windows)
#    - Windows 9x/Me:   %windir%\hosts
#               (%windir% value is usually c:\windows)
#    - Cygwin:       /etc/hosts
#
#    The file contains newline-separated definitions, in the
#    form ip_address_in_dotted_form name [name ...] names are
#    whitespace-separated. Lines beginning with an hash (#)
#    character are comments.
#
#    The file is checked at startup and upon configuration.
#    If set to 'none', it won't be checked.
#    If append_domain is used, that domain will be added to
#    domain-local (i.e. not containing any dot character) host
#    definitions.
#Default:
# hosts_file /etc/hosts

#  TAG: append_domain
#    Appends local domain name to hostnames without any dots in
#    them.  append_domain must begin with a period.
#
#    Be warned there are now Internet names with no dots in
#    them using only top-domain names, so setting this may
#    cause some Internet sites to become unavailable.
#
#Example:
# append_domain .yourdomain.com
#Default:
# Use operating system definitions

#  TAG: ignore_unknown_nameservers
#    By default Squid checks that DNS responses are received
#    from the same IP addresses they are sent to.  If they
#    don't match, Squid ignores the response and writes a warning
#    message to cache.log.  You can allow responses from unknown
#    nameservers by setting this option to 'off'.
#Default:
# ignore_unknown_nameservers on

#  TAG: ipcache_size    (number of entries)
#    Maximum number of DNS IP cache entries.
#Default:
# ipcache_size 1024

#  TAG: ipcache_low    (percent)
#Default:
# ipcache_low 90

#  TAG: ipcache_high    (percent)
#    The size, low-, and high-water marks for the IP cache.
#Default:
# ipcache_high 95

#  TAG: fqdncache_size    (number of entries)
#    Maximum number of FQDN cache entries.
#Default:
# fqdncache_size 1024

# MISCELLANEOUS
# -----------------------------------------------------------------------------

#  TAG: configuration_includes_quoted_values    on|off
#    If set, Squid will recognize each "quoted string" after a configuration
#    directive as a single parameter. The quotes are stripped before the
#    parameter value is interpreted or used.
#    See "Values with spaces, quotes, and other special characters"
#    section for more details.
#Default:
# configuration_includes_quoted_values off

#  TAG: memory_pools    on|off
#    If set, Squid will keep pools of allocated (but unused) memory
#    available for future use.  If memory is a premium on your
#    system and you believe your malloc library outperforms Squid
#    routines, disable this.
#Default:
# memory_pools on

#  TAG: memory_pools_limit    (bytes)
#    Used only with memory_pools on:
#    memory_pools_limit 50 MB
#
#    If set to a non-zero value, Squid will keep at most the specified
#    limit of allocated (but unused) memory in memory pools. All free()
#    requests that exceed this limit will be handled by your malloc
#    library. Squid does not pre-allocate any memory, just safe-keeps
#    objects that otherwise would be free()d. Thus, it is safe to set
#    memory_pools_limit to a reasonably high value even if your
#    configuration will use less memory.
#
#    If set to none, Squid will keep all memory it can. That is, there
#    will be no limit on the total amount of memory used for safe-keeping.
#
#    To disable memory allocation optimization, do not set
#    memory_pools_limit to 0 or none. Set memory_pools to "off" instead.
#
#    An overhead for maintaining memory pools is not taken into account
#    when the limit is checked. This overhead is close to four bytes per
#    object kept. However, pools may actually _save_ memory because of
#    reduced memory thrashing in your malloc library.
#Default:
# memory_pools_limit 5 MB

#  TAG: forwarded_for    on|off|transparent|truncate|delete
#    If set to "on", Squid will append your client's IP address
#    in the HTTP requests it forwards. By default it looks like:
#
#        X-Forwarded-For: 192.1.2.3
#
#    If set to "off", it will appear as
#
#        X-Forwarded-For: unknown
#
#    If set to "transparent", Squid will not alter the
#    X-Forwarded-For header in any way.
#
#    If set to "delete", Squid will delete the entire
#    X-Forwarded-For header.
#
#    If set to "truncate", Squid will remove all existing
#    X-Forwarded-For entries, and place the client IP as the sole entry.
#Default:
# forwarded_for on

#  TAG: cachemgr_passwd
#    Specify passwords for cachemgr operations.
#
#    Usage: cachemgr_passwd password action action ...
#
#    Some valid actions are (see cache manager menu for a full list):
#        5min
#        60min
#        asndb
#        authenticator
#        cbdata
#        client_list
#        comm_incoming
#        config *
#        counters
#        delay
#        digest_stats
#        dns
#        events
#        filedescriptors
#        fqdncache
#        histograms
#        http_headers
#        info
#        io
#        ipcache
#        mem
#        menu
#        netdb
#        non_peers
#        objects
#        offline_toggle *
#        pconn
#        peer_select
#        reconfigure *
#        redirector
#        refresh
#        server_list
#        shutdown *
#        store_digest
#        storedir
#        utilization
#        via_headers
#        vm_objects
#
#    * Indicates actions which will not be performed without a
#      valid password, others can be performed if not listed here.
#
#    To disable an action, set the password to "disable".
#    To allow performing an action without a password, set the
#    password to "none".
#
#    Use the keyword "all" to set the same password for all actions.
#
#Example:
# cachemgr_passwd secret shutdown
# cachemgr_passwd lesssssssecret info stats/objects
# cachemgr_passwd disable all
#Default:
# No password. Actions which require password are denied.

#  TAG: client_db    on|off
#    If you want to disable collecting per-client statistics,
#    turn off client_db here.
#Default:
# client_db on

#  TAG: refresh_all_ims    on|off
#    When you enable this option, squid will always check
#    the origin server for an update when a client sends an
#    If-Modified-Since request.  Many browsers use IMS
#    requests when the user requests a reload, and this
#    ensures those clients receive the latest version.
#
#    By default (off), squid may return a Not Modified response
#    based on the age of the cached version.
#Default:
# refresh_all_ims off

#  TAG: reload_into_ims    on|off
#    When you enable this option, client no-cache or ``reload''
#    requests will be changed to If-Modified-Since requests.
#    Doing this VIOLATES the HTTP standard.  Enabling this
#    feature could make you liable for problems which it
#    causes.
#
#    see also refresh_pattern for a more selective approach.
#Default:
# reload_into_ims off

#  TAG: connect_retries
#    Limits the number of reopening attempts when establishing a single
#    TCP connection. All these attempts must still complete before the
#    applicable connection opening timeout expires.
#
#    By default and when connect_retries is set to zero, Squid does not
#    retry failed connection opening attempts.
#
#    The (not recommended) maximum is 10 tries. An attempt to configure a
#    higher value results in the value of 10 being used (with a warning).
#
#    Squid may open connections to retry various high-level forwarding
#    failures. For an outside observer, that activity may look like a
#    low-level connection reopening attempt, but those high-level retries
#    are governed by forward_max_tries instead.
#
#    See also: connect_timeout, forward_timeout, icap_connect_timeout,
#    ident_timeout, and forward_max_tries.
#Default:
# Do not retry failed connections.

#  TAG: retry_on_error
#    If set to ON Squid will automatically retry requests when
#    receiving an error response with status 403 (Forbidden),
#    500 (Internal Error), 501 or 503 (Service not available).
#    Status 502 and 504 (Gateway errors) are always retried.
#
#    This is mainly useful if you are in a complex cache hierarchy to
#    work around access control errors.
#
#    NOTE: This retry will attempt to find another working destination.
#    Which is different from the server which just failed.
#Default:
# retry_on_error off

#  TAG: as_whois_server
#    WHOIS server to query for AS numbers.  NOTE: AS numbers are
#    queried only when Squid starts up, not for every request.
#Default:
# as_whois_server whois.ra.net

#  TAG: offline_mode
#    Enable this option and Squid will never try to validate cached
#    objects.
#Default:
# offline_mode off

#  TAG: uri_whitespace
#    What to do with requests that have whitespace characters in the
#    URI.  Options:
#
#    strip:  The whitespace characters are stripped out of the URL.
#        This is the behavior recommended by RFC2396 and RFC3986
#        for tolerant handling of generic URI.
#        NOTE: This is one difference between generic URI and HTTP URLs.
#
#    deny:   The request is denied.  The user receives an "Invalid
#        Request" message.
#        This is the behaviour recommended by RFC2616 for safe
#        handling of HTTP request URL.
#
#    allow:  The request is allowed and the URI is not changed.  The
#        whitespace characters remain in the URI.  Note the
#        whitespace is passed to redirector processes if they
#        are in use.
#        Note this may be considered a violation of RFC2616
#        request parsing where whitespace is prohibited in the
#        URL field.
#
#    encode:    The request is allowed and the whitespace characters are
#        encoded according to RFC1738.
#
#    chop:    The request is allowed and the URI is chopped at the
#        first whitespace.
#
#
#    NOTE the current Squid implementation of encode and chop violates
#    RFC2616 by not using a 301 redirect after altering the URL.
#Default:
# uri_whitespace strip

#  TAG: chroot
#    Specifies a directory where Squid should do a chroot() while
#    initializing.  This also causes Squid to fully drop root
#    privileges after initializing.  This means, for example, if you
#    use a HTTP port less than 1024 and try to reconfigure, you may
#    get an error saying that Squid can not open the port.
#Default:
# none

#  TAG: pipeline_prefetch
#    HTTP clients may send a pipeline of 1+N requests to Squid using a
#    single connection, without waiting for Squid to respond to the first
#    of those requests. This option limits the number of concurrent
#    requests Squid will try to handle in parallel. If set to N, Squid
#    will try to receive and process up to 1+N requests on the same
#    connection concurrently.
#
#    Defaults to 0 (off) for bandwidth management and access logging
#    reasons.
#
#    NOTE: pipelining requires persistent connections to clients.
#
#    WARNING: pipelining breaks NTLM and Negotiate/Kerberos authentication.
#Default:
# Do not pre-parse pipelined requests.

#  TAG: high_response_time_warning    (msec)
#    If the one-minute median response time exceeds this value,
#    Squid prints a WARNING with debug level 0 to get the
#    administrators attention.  The value is in milliseconds.
#Default:
# disabled.

#  TAG: high_page_fault_warning
#    If the one-minute average page fault rate exceeds this
#    value, Squid prints a WARNING with debug level 0 to get
#    the administrators attention.  The value is in page faults
#    per second.
#Default:
# disabled.

#  TAG: high_memory_warning
# Note: This option is only available if Squid is rebuilt with the
#       GNU Malloc with mstats()
#
#    If the memory usage (as determined by gnumalloc, if available and used)
#    exceeds    this amount, Squid prints a WARNING with debug level 0 to get
#    the administrators attention.
#Default:
# disabled.

#  TAG: sleep_after_fork    (microseconds)
#    When this is set to a non-zero value, the main Squid process
#    sleeps the specified number of microseconds after a fork()
#    system call. This sleep may help the situation where your
#    system reports fork() failures due to lack of (virtual)
#    memory. Note, however, if you have a lot of child
#    processes, these sleep delays will add up and your
#    Squid will not service requests for some amount of time
#    until all the child processes have been started.
#    On Windows value less then 1000 (1 milliseconds) are
#    rounded to 1000.
#Default:
# sleep_after_fork 0

#  TAG: windows_ipaddrchangemonitor    on|off
# Note: This option is only available if Squid is rebuilt with the
#       MS Windows
#
#    On Windows Squid by default will monitor IP address changes and will
#    reconfigure itself after any detected event. This is very useful for
#    proxies connected to internet with dial-up interfaces.
#    In some cases (a Proxy server acting as VPN gateway is one) it could be
#    desiderable to disable this behaviour setting this to 'off'.
#    Note: after changing this, Squid service must be restarted.
#Default:
# windows_ipaddrchangemonitor on

#  TAG: eui_lookup
#    Whether to lookup the EUI or MAC address of a connected client.
#Default:
# eui_lookup on

#  TAG: max_filedescriptors
#    Set the maximum number of filedescriptors, either below the
#    operating system default or up to the hard limit.
#
#    Remove from squid.conf to inherit the current ulimit soft
#    limit setting.
#
#    Note: Changing this requires a restart of Squid. Also
#    not all I/O types supports large values (eg on Windows).
#Default:
# Use operating system soft limit set by ulimit.

#  TAG: force_request_body_continuation
#    This option controls how Squid handles data upload requests from HTTP
#    and FTP agents that require a "Please Continue" control message response
#    to actually send the request body to Squid. It is mostly useful in
#    adaptation environments.
#
#    When Squid receives an HTTP request with an "Expect: 100-continue"
#    header or an FTP upload command (e.g., STOR), Squid normally sends the
#    request headers or FTP command information to an adaptation service (or
#    peer) and waits for a response. Most adaptation services (and some
#    broken peers) may not respond to Squid at that stage because they may
#    decide to wait for the HTTP request body or FTP data transfer. However,
#    that request body or data transfer may never come because Squid has not
#    responded with the HTTP 100 or FTP 150 (Please Continue) control message
#    to the request sender yet!
#
#    An allow match tells Squid to respond with the HTTP 100 or FTP 150
#    (Please Continue) control message on its own, before forwarding the
#    request to an adaptation service or peer. Such a response usually forces
#    the request sender to proceed with sending the body. A deny match tells
#    Squid to delay that control response until the origin server confirms
#    that the request body is needed. Delaying is the default behavior.
#Default:
# Deny, unless rules exist in squid.conf.

#  TAG: http_upgrade_request_protocols
#    Controls client-initiated and server-confirmed switching from HTTP to
#    another protocol (or to several protocols) using HTTP Upgrade mechanism
#    defined in RFC 7230 Section 6.7. Squid itself does not understand the
#    protocols being upgraded to and participates in the upgraded
#    communication only as a dumb TCP proxy. Admins should not allow
#    upgrading to protocols that require a more meaningful proxy
#    participation.
#
#    Usage: http_upgrade_request_protocols <protocol> allow|deny [!]acl ...
#
#    The required "protocol" parameter is either an all-caps word OTHER or an
#    explicit protocol name (e.g. "WebSocket") optionally followed by a slash
#    and a version token (e.g. "HTTP/3"). Explicit protocol names and
#    versions are case sensitive.
#
#    When an HTTP client sends an Upgrade request header, Squid iterates over
#    the client-offered protocols and, for each protocol P (with an optional
#    version V), evaluates the first non-empty set of
#    http_upgrade_request_protocols rules (if any) from the following list:
#
#        * All rules with an explicit protocol name equal to P.
#        * All rules that use OTHER instead of a protocol name.
#
#    In other words, rules using OTHER are considered for protocol P if and
#    only if there are no rules mentioning P by name.
#
#    If both of the above sets are empty, then Squid removes protocol P from
#    the Upgrade offer.
#
#    If the client sent a versioned protocol offer P/X, then explicit rules
#    referring to the same-name but different-version protocol P/Y are
#    declared inapplicable. Inapplicable rules are not evaluated (i.e. are
#    ignored). However, inapplicable rules still belong to the first set of
#    rules for P.
#
#    Within the applicable rule subset, individual rules are evaluated in
#    their configuration order. If all ACLs of an applicable "allow" rule
#    match, then the protocol offered by the client is forwarded to the next
#    hop as is. If all ACLs of an applicable "deny" rule match, then the
#    offer is dropped. If no applicable rules have matching ACLs, then the
#    offer is also dropped. The first matching rule also ends rules
#    evaluation for the offered protocol.
#
#    If all client-offered protocols are removed, then Squid forwards the
#    client request without the Upgrade header. Squid never sends an empty
#    Upgrade request header.
#
#    An Upgrade request header with a value violating HTTP syntax is dropped
#    and ignored without an attempt to use extractable individual protocol
#    offers.
#
#    Upon receiving an HTTP 101 (Switching Protocols) control message, Squid
#    checks that the server listed at least one protocol name and sent a
#    Connection:upgrade response header. Squid does not understand individual
#    protocol naming and versioning concepts enough to implement stricter
#    checks, but an admin can restrict HTTP 101 (Switching Protocols)
#    responses further using http_reply_access. Responses denied by
#    http_reply_access rules and responses flagged by the internal Upgrade
#    checks result in HTTP 502 (Bad Gateway) ERR_INVALID_RESP errors and
#    Squid-to-server connection closures.
#
#    If Squid sends an Upgrade request header, and the next hop (e.g., the
#    origin server) responds with an acceptable HTTP 101 (Switching
#    Protocols), then Squid forwards that message to the client and becomes
#    a TCP tunnel.
#
#    The presence of an Upgrade request header alone does not preclude cache
#    lookups. In other words, an Upgrade request might be satisfied from the
#    cache, using regular HTTP caching rules.
#
#    This clause only supports fast acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#
#    Each of the following groups of configuration lines represents a
#    separate configuration example:
#
#    # never upgrade to protocol Foo; all others are OK
#    http_upgrade_request_protocols Foo deny all
#    http_upgrade_request_protocols OTHER allow all
#
#    # only allow upgrades to protocol Bar (except for its first version)
#    http_upgrade_request_protocols Bar/1 deny all
#    http_upgrade_request_protocols Bar allow all
#    http_upgrade_request_protocols OTHER deny all # this rule is optional
#
#    # only allow upgrades to protocol Baz, and only if Baz is the only offer
#    acl UpgradeHeaderHasMultipleOffers ...
#    http_upgrade_request_protocols Baz deny UpgradeHeaderHasMultipleOffers
#    http_upgrade_request_protocols Baz allow all
#Default:
# Upgrade header dropped, effectively blocking an upgrade attempt.

#  TAG: server_pconn_for_nonretriable
#    This option provides fine-grained control over persistent connection
#    reuse when forwarding HTTP requests that Squid cannot retry. It is useful
#    in environments where opening new connections is very expensive
#    (e.g., all connections are secured with TLS with complex client and server
#    certificate validation) and race conditions associated with persistent
#    connections are very rare and/or only cause minor problems.
#
#    HTTP prohibits retrying unsafe and non-idempotent requests (e.g., POST).
#    Squid limitations also prohibit retrying all requests with bodies (e.g., PUT).
#    By default, when forwarding such "risky" requests, Squid opens a new
#    connection to the server or cache_peer, even if there is an idle persistent
#    connection available. When Squid is configured to risk sending a non-retriable
#    request on a previously used persistent connection, and the server closes
#    the connection before seeing that risky request, the user gets an error response
#    from Squid. In most cases, that error response will be HTTP 502 (Bad Gateway)
#    with ERR_ZERO_SIZE_OBJECT or ERR_WRITE_ERROR (peer connection reset) error detail.
#
#    If an allow rule matches, Squid reuses an available idle persistent connection
#    (if any) for the request that Squid cannot retry. If a deny rule matches, then
#    Squid opens a new connection for the request that Squid cannot retry.
#
#    This option does not affect requests that Squid can retry. They will reuse idle
#    persistent connections (if any).
#
#    This clause only supports fast acl types.
#    See http://wiki.squid-cache.org/SquidFaq/SquidAcl for details.
#
#    Example:
#        acl SpeedIsWorthTheRisk method POST
#        server_pconn_for_nonretriable allow SpeedIsWorthTheRisk
#Default:
# Open new connections for forwarding requests Squid cannot retry safely.

#  TAG: happy_eyeballs_connect_timeout    (msec)
#    This Happy Eyeballs (RFC 8305) tuning directive specifies the minimum
#    delay between opening a primary to-server connection and opening a
#    spare to-server connection for the same master transaction. This delay
#    is similar to the Connection Attempt Delay in RFC 8305, but it is only
#    applied to the first spare connection attempt. Subsequent spare
#    connection attempts use happy_eyeballs_connect_gap, and primary
#    connection attempts are not artificially delayed at all.
#
#    Terminology: The "primary" and "spare" designations are determined by
#    the order of DNS answers received by Squid: If Squid DNS AAAA query
#    was answered first, then primary connections are connections to IPv6
#    peer addresses (while spare connections use IPv4 addresses).
#    Similarly, if Squid DNS A query was answered first, then primary
#    connections are connections to IPv4 peer addresses (while spare
#    connections use IPv6 addresses).
#
#    Shorter happy_eyeballs_connect_timeout values reduce master
#    transaction response time, potentially improving user-perceived
#    response times (i.e., making user eyeballs happier). Longer delays
#    reduce both concurrent connection level and server bombardment with
#    connection requests, potentially improving overall Squid performance
#    and reducing the chance of being blocked by servers for opening too
#    many unused connections.
#
#    RFC 8305 prohibits happy_eyeballs_connect_timeout values smaller than
#    10 (milliseconds) to "avoid congestion collapse in the presence of
#    high packet-loss rates".
#
#    The following Happy Eyeballs directives place additional connection
#    opening restrictions: happy_eyeballs_connect_gap and
#    happy_eyeballs_connect_limit.
#Default:
# happy_eyeballs_connect_timeout 250

#  TAG: happy_eyeballs_connect_gap    (msec)
#    This Happy Eyeballs (RFC 8305) tuning directive specifies the
#    minimum delay between opening spare to-server connections (to any
#    server; i.e. across all concurrent master transactions in a Squid
#    instance). Each SMP worker currently multiplies the configured gap
#    by the total number of workers so that the combined spare connection
#    opening rate of a Squid instance obeys the configured limit. The
#    workers do not coordinate connection openings yet; a micro burst
#    of spare connection openings may violate the configured gap.
#
#    This directive has similar trade-offs as
#    happy_eyeballs_connect_timeout, but its focus is on limiting traffic
#    amplification effects for Squid as a whole, while
#    happy_eyeballs_connect_timeout works on an individual master
#    transaction level.
#
#    The following Happy Eyeballs directives place additional connection
#    opening restrictions: happy_eyeballs_connect_timeout and
#    happy_eyeballs_connect_limit. See the former for related terminology.
#Default:
# no artificial delays between spare attempts

#  TAG: happy_eyeballs_connect_limit
#    This Happy Eyeballs (RFC 8305) tuning directive specifies the
#    maximum number of spare to-server connections (to any server; i.e.
#    across all concurrent master transactions in a Squid instance).
#    Each SMP worker gets an equal share of the total limit. However,
#    the workers do not share the actual connection counts yet, so one
#    (busier) worker cannot "borrow" spare connection slots from another
#    (less loaded) worker.
#
#    Setting this limit to zero disables concurrent use of primary and
#    spare TCP connections: Spare connection attempts are made only after
#    all primary attempts fail. However, Squid would still use the
#    DNS-related optimizations of the Happy Eyeballs approach.
#
#    This directive has similar trade-offs as happy_eyeballs_connect_gap,
#    but its focus is on limiting Squid overheads, while
#    happy_eyeballs_connect_gap focuses on the origin server and peer
#    overheads.
#
#    The following Happy Eyeballs directives place additional connection
#    opening restrictions: happy_eyeballs_connect_timeout and
#    happy_eyeballs_connect_gap. See the former for related terminology.
#Default:
# no artificial limit on the number of concurrent spare attempts
EOF

# CREATE WHITELIST
if [ ! -f "${SQUID_WHITELIST}" ]; then touch "${SQUID_WHITELIST}"; fi
cat > "${SQUID_WHITELIST}" <<'EOF' && echo -e "The whitelist was created successfully!" || echo -e "The whitelist failed to create."
<replace with your own list>
site.com
www.site.com
EOF

# CREATE BLACKLIST
if [ -f "${SQUID_BLACKLIST}" ]; then touch "${SQUID_BLACKLIST}" ;fi
cat > "${SQUID_BLACKLIST}" <<'EOF' && echo -e "The blacklist was created successfully!\\n" || echo -e "The blacklist failed to create.\\n"
<replace with your own list>
.bytedance.com
.tiktok.com
.xyz
EOF

# RUN HTPASSWD TO CREATE PASSWORD FOR USE
if [ ! -f "${SQUID_PASSWD}" ]; then
    htpasswd -c "${SQUID_PASSWD}" squid && echo -e "\\nThe squid passwd file was created successfully!" || echo -e "\\nThe squid passwd file failed to create."
    echo
    cat "${SQUID_PASSWD}"
    echo
fi

# FIREWALLD SETTINGS
echo '[1] Add firewalld rules'
echo -e "[2] Skip\\n"
read -p 'Enter a number: ' uChoice
echo
if [[ "${uChoice}" == "1" ]]; then
    firewall-cmd --permanent --add-service={"${SVC01}","${SVC02}","${SVC03}","${SVC04}","${SVC05}"}
    firewall-cmd --add-zone=squid-custom
    firewall-cmd --permanent --zone=squid-custom --add-interface=lo
    firewall-cmd --permanent --zone=squid-custom --add-port={"${PORT_SQUID}","${PORT_PIHOLE}"}
    firewall-cmd --set-default-zone=squid-custom
    firewall-cmd --reload
    echo
    read -t 10 -p 'Sleeping for 10 seconds. Press enter to skip ahead.'
    clear
else
    clear
fi

# RESTART SQUID VIA SYSTEMCTL
'/etc/init.d/squid' restart && echo -e "\\nSquid restarted successfully!\\n" || echo -e "\\nSquid failed to restart!\\n"