# --------------------
# VARIABLE SETTINGS PER SYSTEM
#
# TLS settings.
#
# SSL key, certificate, CA
#
smtpd_tls_key_file = /etc/ssl/private/2020.mail.intern.xxx.xxx.key
smtpd_tls_cert_file = /etc/ssl/certs/2020.mail.intern.xxx.xxx.crt
smtpd_tls_CAfile = /etc/ssl/certs/2020.mail.intern.xxx.xxx.crt
smtpd_tls_CApath = /etc/ssl/certs

# Use the same CA file as smtpd.
smtp_tls_CApath = /etc/ssl/certs
smtp_tls_CAfile = $smtpd_tls_CAfile
smtp_tls_note_starttls_offer = yes

# Virtual support.
virtual_minimum_uid = 2000
virtual_uid_maps = static:2000
virtual_gid_maps = static:2000
virtual_mailbox_base = /maildata/mailbox
virtual_mailbox_domains = /maildata/vhosts
virtual_mailbox_maps = hash:/maildata/vmaps

# Do not set virtual_alias_domains.
virtual_alias_domains =

# hostname
myhostname = bgrsld-mail0.intern.xxx.xxx
mydomain = mail.intern.xxx.xxx
myorigin = $mydomain

# Default message_size_limit.
# 15 MiB
message_size_limit = 15728640

#
# Lookup virtual mail accounts
#

relay_domains = $mydestination

#
# Dovecot SASL support.
#
smtpd_sasl_type = dovecot
smtpd_sasl_path = private/dovecot-auth
virtual_transport = dovecot
dovecot_destination_recipient_limit = 1

postscreen_dnsbl_reply_map = texthash:/etc/postfix/postscreen_dnsbl_reply
postscreen_access_list = permit_mynetworks cidr:/etc/postfix/postscreen_access.cidr

# --------------------
# INSTALL-TIME CONFIGURATION INFORMATION
#
# location of the Postfix queue. Default is /var/spool/postfix.
queue_directory = /var/spool/postfix

# location of all postXXX commands. Default is /usr/sbin.
command_directory = /usr/sbin

# location of all Postfix daemon programs (i.e. programs listed in the
# master.cf file). This directory must be owned by root.
# Default is /usr/libexec/postfix
daemon_directory = /usr/lib/postfix/sbin

# location of Postfix-writable data files (caches, random numbers).
# This directory must be owned by the mail_owner account (see below).
# Default is /var/lib/postfix.
data_directory = /var/lib/postfix

# owner of the Postfix queue and of most Postfix daemon processes.
# Specify the name of a user account THAT DOES NOT SHARE ITS USER OR GROUP ID
# WITH OTHER ACCOUNTS AND THAT OWNS NO OTHER FILES OR PROCESSES ON THE SYSTEM.
# In particular, don't specify nobody or daemon. PLEASE USE A DEDICATED USER.
# Default is postfix.
mail_owner = postfix

# The following parameters are used when installing a new Postfix version.
#
# sendmail_path: The full pathname of the Postfix sendmail command.
# This is the Sendmail-compatible mail posting interface.
#
sendmail_path = /usr/sbin/sendmail

# newaliases_path: The full pathname of the Postfix newaliases command.
# This is the Sendmail-compatible command to build alias databases.
#
newaliases_path = /usr/bin/newaliases

# full pathname of the Postfix mailq command.  This is the Sendmail-compatible
# mail queue listing command.
mailq_path = /usr/bin/mailq

# group for mail submission and queue management commands.
# This must be a group name with a numerical group ID that is not shared with
# other accounts, not even with the Postfix account.
setgid_group = postdrop

# external command that is executed when a Postfix daemon program is run with
# the -D option.
#
# Use "command .. & sleep 5" so that the debugger can attach before
# the process marches on. If you use an X-based debugger, be sure to
# set up your XAUTHORITY environment variable before starting Postfix.
#
debugger_command =
    PATH=/bin:/usr/bin:/usr/local/bin:/usr/X11R6/bin
    ddd $daemon_directory/$process_name $process_id & sleep 5

debug_peer_level = 2

# --------------------
# CUSTOM SETTINGS
#

# SMTP server response code when recipient or domain not found.
unknown_local_recipient_reject_code = 550

# Do not notify local user.
biff = no

# Disable the rewriting of "site!user" into "user@site".
swap_bangpath = no

# Disable the rewriting of the form "user%domain" to "user@domain".
allow_percent_hack = no

# Allow recipient address start with '-'.
allow_min_user = no

# Disable the SMTP VRFY command. This stops some techniques used to
# harvest email addresses.
disable_vrfy_command = yes

# Enable both IPv4 and/or IPv6: ipv4, ipv6, all.
inet_protocols = all

# Enable all network interfaces.
inet_interfaces = all

#
# Disable SSLv2, SSLv3
#
smtpd_tls_protocols = !SSLv2 !SSLv3
smtpd_tls_mandatory_protocols = !SSLv2 !SSLv3
smtp_tls_protocols = !SSLv2 !SSLv3
smtp_tls_mandatory_protocols = !SSLv2 !SSLv3
lmtp_tls_protocols = !SSLv2 !SSLv3
lmtp_tls_mandatory_protocols = !SSLv2 !SSLv3

#
# Fix 'The Logjam Attack'.
#
smtpd_tls_exclude_ciphers = aNULL, eNULL, EXPORT, DES, RC4, MD5, PSK, aECDH, EDH-DSS-DES-CBC3-SHA, EDH-RSA-DES-CDC3-SHA, KRB5-DE5, CBC3-SHA
smtpd_tls_dh512_param_file = /etc/ssl/dh512_param.pem
smtpd_tls_dh1024_param_file = /etc/ssl/dh2048_param.pem

tls_random_source = dev:/dev/urandom

# Log only a summary message on TLS handshake completion — no logging of client
# certificate trust-chain verification errors if client certificate
# verification is not required. With Postfix 2.8 and earlier, log the summary
# message, peer certificate summary information and unconditionally log
# trust-chain verification errors.
smtp_tls_loglevel = 1
smtpd_tls_loglevel = 1

# Opportunistic TLS: announce STARTTLS support to remote SMTP clients, but do
# not require that clients use TLS encryption.
smtpd_tls_security_level = may

# Produce `Received:` message headers that include information about the
# protocol and cipher used, as well as the remote SMTP client CommonName and
# client certificate issuer CommonName.
# This is disabled by default, as the information may be modified in transit
# through other mail servers. Only information that was recorded by the final
# destination can be trusted.
#smtpd_tls_received_header = yes

# Opportunistic TLS, used when Postfix sends email to remote SMTP server.
# Use TLS if this is supported by the remote SMTP server, otherwise use
# plaintext.
# References:
#   - http://www.postfix.org/TLS_README.html#client_tls_may
#   - http://www.postfix.org/postconf.5.html#smtp_tls_security_level
smtp_tls_security_level = may

# Enable long, non-repeating, queue IDs (queue file names).
# The benefit of non-repeating names is simpler logfile analysis and easier
# queue migration (there is no need to run "postsuper" to change queue file
# names that don't match their message file inode number).
enable_long_queue_ids = yes

# Reject unlisted sender and recipient
smtpd_reject_unlisted_recipient = yes
smtpd_reject_unlisted_sender = yes

# A mechanism to transform commands from remote SMTP clients.
# This is a last-resort tool to work around client commands that break
# interoperability with the Postfix SMTP server. Other uses involve fault
# injection to test Postfix's handling of invalid commands.
# Requires Postfix-2.7+.
smtpd_command_filter = pcre:/etc/postfix/command_filter.pcre

# HELO restriction
smtpd_helo_required = yes
smtpd_helo_restrictions =
    permit_mynetworks
    permit_sasl_authenticated
    check_helo_access pcre:/etc/postfix/helo_access.pcre
    reject_non_fqdn_helo_hostname
    reject_unknown_helo_hostname

# Sender restrictions
smtpd_sender_restrictions =
    reject_non_fqdn_sender
    reject_unlisted_sender
    permit_mynetworks
    permit_sasl_authenticated
    check_sender_access pcre:/etc/postfix/sender_access.pcre
    reject_unknown_sender_domain

# Recipient restrictions
smtpd_recipient_restrictions =
    reject_non_fqdn_recipient
    reject_unlisted_recipient
    check_policy_service inet:127.0.0.1:7777
    permit_mynetworks
    permit_sasl_authenticated
    reject_unauth_destination
    check_policy_service inet:127.0.0.1:12340

# END-OF-MESSAGE restrictions
smtpd_end_of_data_restrictions =
    check_policy_service inet:127.0.0.1:7777

# Data restrictions
smtpd_data_restrictions = reject_unauth_pipelining

# SRS (Sender Rewriting Scheme) support
#sender_canonical_maps = tcp:127.0.0.1:7778
#sender_canonical_classes = envelope_sender
#recipient_canonical_maps = tcp:127.0.0.1:7779
#recipient_canonical_classes= envelope_recipient,header_recipient

proxy_read_maps = $canonical_maps $lmtp_generic_maps $local_recipient_maps $mydestination $mynetworks $recipient_bcc_maps $recipient_canonical_maps $relay_domains $relay_recipient_maps $relocated_maps $sender_bcc_maps $sender_canonical_maps $smtp_generic_maps $smtpd_sender_login_maps $transport_maps $virtual_alias_domains $virtual_alias_maps $virtual_mailbox_domains $virtual_mailbox_maps $smtpd_sender_restrictions $sender_dependent_relayhost_maps

# Avoid duplicate recipient messages. Default is 'yes'.
enable_original_recipient = no

#
# Enable SASL authentication on port 25 and force TLS-encrypted SASL authentication.
# WARNING: NOT RECOMMENDED to enable smtp auth on port 25, all end users should
#          be forced to submit email through port 587 instead.
#
#smtpd_sasl_auth_enable = yes
#smtpd_sasl_security_options = noanonymous
#smtpd_tls_auth_only = yes

# trusted SMTP clients which are allowed to relay mail through Postfix.
#
# Note: additional IP addresses/networks listed in mynetworks should be listed
#       in iRedAPD setting 'MYNETWORKS' (in `/opt/iredapd/settings.py`) too.
#       for example:
#
#       MYNETWORKS = ['xx.xx.xx.xx', 'xx.xx.xx.0/24', ...]
#
mynetworks = 127.0.0.1 [::1]

# Accepted local emails
mydestination = $myhostname, localhost, localhost.localdomain

# The set of characters that can separate a user name from its extension
# (example: user+foo), or a .forward file name from its extension (example:
# .forward+foo).
# Postfix 2.11 and later supports multiple characters.
recipient_delimiter = +

# The time after which the sender receives a copy of the message headers of
# mail that is still queued. Default setting is disabled (0h) by Postfix.
#delay_warning_time = 1h

# Do not display the name of the recipient table in the "User unknown" responses.
# The extra detail makes trouble shooting easier but also reveals information
# that is nobody elses business.
show_user_unknown_table_name = no
compatibility_level = 2

#
# Postscreen
#
postscreen_greet_action = drop
postscreen_blacklist_action = drop
postscreen_dnsbl_action = drop
postscreen_dnsbl_threshold = 2

# Attention:
#   - zen.spamhaus.org free tire has 3 limits
#     (https://www.spamhaus.org/organization/dnsblusage/):
#
#     1) Your use of the Spamhaus DNSBLs is non-commercial*, and
#     2) Your email traffic is less than 100,000 SMTP connections per day, and
#     3) Your DNSBL query volume is less than 300,000 queries per day.
#
#   - FAQ: "Your DNSBL blocks nothing at all!"
#     https://www.spamhaus.org/faq/section/DNSBL%20Usage#261
#
# It's strongly recommended to use a local DNS server for cache.
#postscreen_dnsbl_sites =
#    zen.spamhaus.org=127.0.0.[2..11]*3
#    b.barracudacentral.org=127.0.0.2*2

# Require Postfix-2.11+
postscreen_dnsbl_whitelist_threshold = -2

#
# mlmmj - mailing list manager
#
#mlmmj_destination_recipient_limit = 1

#
# Amavisd + SpamAssassin + ClamAV
#
#content_filter = smtp-amavis:[127.0.0.1]:10024

# Concurrency per recipient limit.
#smtp-amavis_destination_recipient_limit = 1