View difference between Paste ID: vcVC9iL9 and dSvQS2iY

 #!/bin/bash
 
 # 23/10/2013
 # This script attempts to semi-automate / automate the wifi connection
 # process from the command line.
 # It is intended to be used on a headless machine without the
 # requirement of typing several commands for a connection.
 # The script stores previous connection credentials in PLAINTEXT as
 # *.wpa files in the executed directory and in /etc/wpasupplicant.conf.
 # These .wpa files are used to connect to several different AP using
 # previously stored info.
 # Probably a good idea to stop and other network managing software while
 # running this script, also in testing wpa_supplicant does a pretty good
 # job of re-connecting a disassociated link automatically.
 #
 # Mainly created from a combination of scripts taken from theses two
 # sources:
 # http://www.backtrack-linux.org/forums/archive/index.php/t-3367.html
 # AND
 # http://www.linuxquestions.org/questions/linux-general-1/wifi-connect\
 # -script-tested-in-ubuntu-772646/
 #
 # old version 1  http://pastebin.com/Pa90HBiU  01/06/2013
 # 	very simple first version
 # old version 2  http://pastebin.com/FzJnv5Nk  02/06/2013
 #	minor additions
 # old version 3  http://pastebin.com/3mu1XT5Y  08/06/2013
 #	included ability to call up previous saved files from
 #	command line.  Some checking of command line parameters and
 #	checking for empty saved files
 # old version 4
 #	Added exit return values
 # Current version 5
 #	Removal of cleanslate function.  Capitalising of function names.
 #	Renaming of some function names.
 #	Addition of random_config to randomly select a previously saved
 #	config files, check for internet access and keep trying another
 #	connections if internet access is not made.  Can be used in
 #	conjunction with -f to initially select a conf_file of your choice.
 #	Improved program feedback and internet access checking.
 #
 # This script uses the following commands: find, printf, iwlist, awk,
 # cat, kill, ps, grep, xargs, iwconfig, dhclient, wpa_supplicant, curl.
 #
 # Copy, Distribute and Modify Freely.
 #
 
 
 ########################################################################
 ######################## FUNCTIONS #####################################
 
 function HELP (){
 	HELP_MESSAGE="$1"
 	if [ "$HELP_MESSAGE" ]; then
 		printf "$HELP_MESSAGE"
 	fi
 	printf "Usage: $0 -i [INTERFACE] OR AND -f [CONF_FILE.wpa] -r (RANDOM_CONF_MODE)\n"
 }
 
 
 function CHECK_ARGS () {
 	#
 	# Define Globals
 	#
 	INET_AVAIL=0
 	RANDOM_CONF_MODE=0
 	RANDOM_FIRST_RUN=0
 	CONF_FILE=""
 	INT=""
 
 	if [ -z "$1" ]; then
 	HELP
 	exit 1
 	fi
 
 	while getopts  "i:f:r" opt
 		do
 			case $opt in
 				i ) INT=${OPTARG};;
 				f ) CONF_FILE=${OPTARG};;
 				r ) RANDOM_CONF_MODE=1;;
 				\?) HELP
 					exit 1;;
 				* ) HELP
 					exit 1;;
 			esac
 		done
 
 	#
 	# check if root
 	#
 	if [ "$(id -u)" != "0" ]; then
 		HELP "This script must be run as root\n"
 		exit 1
 	fi
 
 	#
 	# check if interface is entered as command line argument
 	#
 	if [ -z "$INT" ]; then
 		HELP
 		exit 1
 	fi
 
 	#
 	# Check if interface entered exists
 	#
 	if [ ! -e /sys/class/net/$INT ]; then
 		HELP "Network Interface $INT does not exist\n"
 		exit 1
 	fi
 
 	#
 	# If random mode selected, check if wpa files are available
 	#
 	if [ $RANDOM_CONF_MODE -eq 1 ]; then
 		local WPA_FILES=$(find . -type f -name "*.wpa" | wc -l)
 		if [ "$WPA_FILES" -eq 0  ]; then
 			HELP "No *.wpa files exist for RANDOM_CONF_MODE\n"
 			exit 1
 		fi
 	fi
 }
 
 
 function PINGCHECK (){
 	#
-	# Check for an internet connection using curl to download from a FQDN. 5 Second timeout.
+	# Check for an internet connection using curl to download from a
-	# Ref: http://superuser.com/questions/545865/how-to-check-if-internet-connection-is-available-via-terminal/625888#625888
+	# FQDN. 5 Second timeout.
 	# Ref: superuser.com/questions/545865/how-to-check-if-internet-\
 	# connection-is-available-via-terminal/625888
 	#
 	printf "Checking for internet access...\n"
 	curl --interface $INT -o /dev/null -m 5 -s http://www.google.com
 	if [[ $? == 0 ]]; then
 		INET_AVAIL=1
 	else
 		#
 		# Check again for internet access
 		#
 		printf "Rechecking for internet access...\n"
 		curl --interface $INT -o /dev/null -m 5 -s http://www.google.com
 		if [[ $? == 0 ]]; then
 			INET_AVAIL=1
 		else
 			INET_AVAIL=0
 		fi
 	fi
 }
 
 
-	# Accepts a filename argument to read a saved file.  Also can search or use previous saved
+
-	# wpa configuration files.  Will automatically bypass new config prompting if RANDOM_CONF_MODE
+
 	# Accepts a filename argument to read a saved file.  Also can search
-	# Filename checking involves testing file is greater than zero length and exists
+	# or use previous saved
 	# wpa configuration files.  Will automatically bypass new config
 	# prompting if RANDOM_CONF_MODE
 	# is being used.
 	# Filename checking involves testing file is greater than zero
 	# length and exists
 	# before writing the configuration to wpa_supplicant.conf
 	#
 
 	local CONF_FILE=$1
 
 	if [ $RANDOM_CONF_MODE -eq 0 ]; then
 		if [ -n "$CONF_FILE" ]; then
 			if [ -s "$CONF_FILE" ]; then
 				printf "File $CONF_FILE exists, proceeding to connect\n"
 				WRITE_CONF "$CONF_FILE"
 				exit 0
 			else
 				printf "File $CONF_FILE is invalid or does not exist\n"
 				CONF_CREATE
 				exit 0
 			fi
 		fi
 	else
 		if [ -n "$CONF_FILE" ]; then
 			if [ -s "$CONF_FILE" ]; then
 				WRITE_CONF "$CONF_FILE"
 				exit 1
 			else
 				printf "File $CONF_FILE is invalid or does not exist\n"
 				RANDOM_CONF
 				exit 1
 			fi
 		else
 			RANDOM_CONF
 			exit 1
 		fi
 	fi
 
 	#
 	# Save and change IFS so spaces in file names are not interpreted as
 	# separate lines in the array
 	#
-	# ref:http://www.cyberciti.biz/tips/handling-filenames-with-spaces-in-bash.html
+
 	IFS=$'\n'
 
 	#
-	# ref:http://serverfault.com/questions/354403/remove-path-from-find-command-output
+
 	# ref:http://www.cyberciti.biz/tips/handling-filenames-with-spaces-\
 	# in-bash.html
 	#
 	# " -printf '%f\n' " removes path info from outputs
 	#
 	# ref:http://serverfault.com/questions/354403/remove-path-from-find\
 	# -command-output
 	#
 	SAVED_LIST=($(find . -type f -name "*.wpa" -printf '%f\n'))
 
 	#
 	# restore ifs
 	#
 	IFS=$OLDIFS
 
 	#
 	# Tests for number of saved wifi connections, if none exit
 	#
 	if [ -z "${SAVED_LIST[0]}" ]; then
 		printf "There are no previous saved wifi connections\n"
 		#
 		# Create new connection
 		#
 		CONF_CREATE
 		exit 0
 	fi
-	#Select one of the previous saved configurations to connect with or quit
+
 	#
 	#PS3 Sets the prompt for the select statement below
 	#
 	PS3="Choose a previously saved wifi connection or 's' to skip: "
 
 	#
 	# Select one of the previous saved configurations to connect with or
 	# quit
 	#
 	select CONF_FILE in "${SAVED_LIST[@]}"; do
 		#
 		# Quit if selected number does not exist
 		#
 		if [ -z "$CONF_FILE" ] ; then
 				printf "Skipping\n\n"
 				PS3=""
 				CONF_CREATE
 				exit 0
 		fi
 		#
 		# Quick check if file is greater than zero length and exists
 		#
 		if [ -s "$CONF_FILE" ]; then
 			printf "File $CONF_FILE exists, proceeding to connect\n"
 			PS3=""
 			WRITE_CONF "$CONF_FILE"
 			exit 0
 			else
 			printf "File $CONF_FILE is invalid or does not exist, proceeding to create a new configuration\n"
 			PS3=""
 			CONF_CREATE
-	# This function randomly select a previously saved config files, check for internet access and keep trying another
+
-	# connections if internet access is not made.  If and internet connection is not found, it tries another
+
-	# connection.  Could be used as a faiover by specifying -f as your initial preferred network.
+
 }
 
 
 function RANDOM_CONF (){
 	#
-	# Test to check if RANDOM_FIRST_RUN is 1.  If so then proceed to connect using the config file specified first.
+	# This function randomly select a previously saved config files,
 	# check for internet access and keep trying another
 	# connections if internet access is not made.  If and internet
 	# connection is not found, it tries another
 	# connection.  Could be used as a faiover by specifying -f as your
 	# initial preferred network.
 	#
 
-	# Test if INET_AVAIL is 1, initial value is 0 and if connection is good then it is 1.  Used to loop and recheck for
+
-	# a internet connection.  If there is no connection then it go to the random config selection.
+
 	#
 	# Test to check if RANDOM_FIRST_RUN is 1.  If so then proceed to
 	# connect using the config file specified first.
 	#
 	if [ $RANDOM_FIRST_RUN -eq 1 ]; then
 		RANDOM_FIRST_RUN=0
 		READ_SAVED "$CONF_FILE"
 	fi
 
 	#
 	# Test if INET_AVAIL is 1, initial value is 0 and if connection is
 	# good then it is 1.  Used to loop and recheck for
 	# a internet connection.  If there is no connection then it go to
 	# the random config selection.
 	#
 
 	if [ $INET_AVAIL -eq 1 ]; then
 		#
 		# Sleep for a random period of 600 to 900 seconds
 		#
 		sleep $(((RANDOM % 300)+600))
 		PINGCHECK
-	# This is a user entry prompt function, used to create new config files.
+
 	else
 		OLDIFS=$IFS
 		IFS=$'\n'
 		CONF_FILE=($(find . -type f -name "*.wpa" -printf '%f\n'|sort -R |tail -1))
 		IFS=$OLDIFS
 		READ_SAVED "$CONF_FILE"
 	fi
 	exit 1
 }
 
 
 function CONF_CREATE (){
 	#
 	# This is a user entry prompt function, used to create new config
 	# files.
 	#
 
 	#
 	# Scans for wifi connections & isolates wifi AP name
 	#
 	eval LIST=( $(iwlist $INT scan 2>/dev/null | awk -F":" '/ESSID/{print $2}') )
 
 	#
 	#PS3 Sets the prompt for the select statement below
 	#
 	PS3="Choose a new ESSID to create a connection or 'q' to quit: "
 
 	#
 	# Tests for number of wifi connections, exits if none
 	#
 		if [ -z "${LIST[0]}" ]; then
 			printf "No available wifi connection using $INT\n"
 			exit 1
 		fi
 
 	#
 	# Select from a LIST of scanned connections
 	#
 	select CONF_FILE in "${LIST[@]}"; do
 
-		# Append the CONF_FILE variable (ESSID) to .wpa to make a filename
+
-		# for saved configs
+
 		#
 		if [ -z "$CONF_FILE" ] ; then
 				printf "Exiting\n"
 				exit 0
 		fi
 
 		#
 		# Get user input for passphrase no need to escape spaces
 		#
 		printf "Enter the passphrase for $CONF_FILE?\n"
 		read "PASSPHRASE"
 
 		#
 		# Append the CONF_FILE variable (ESSID) to .wpa to make a
 		# filename for saved configs
 		#
 		FILENAME=$CONF_FILE".wpa"
 
 		#
 		# Run wpa_passphrase to generate a file for wpa_supplicant to
 		# use, store it locally and in etc/wpa_supplicant.conf
 		#
 		printf "Running wpa_passphrase\n"
 		wpa_passphrase "$CONF_FILE" "$PASSPHRASE" > "$FILENAME" | xargs
 		#
 		# Jump to WRITE_CONF function, append configuration filename
 		# to CONF_FILE variable
 		#
 
 		PS3=""
 		WRITE_CONF "$FILENAME"
 		exit 1
 	done
 }
 
 
 function WRITE_CONF (){
 
 	local CONF_FILE=$1
 	#
 	# Copy local wpa_supplicant file to etc/wpa_supplicant.conf
 	#
 	printf "Writing new configuration file using $CONF_FILE\n"
 	cat "$CONF_FILE">/etc/wpa_supplicant.conf | xargs
 	#
 	# Jump to connect function, pass on the ESSID variable for connection
 	#
 	CONNECT "$CONF_FILE"
 	exit 1
 }
 
 
 function CONNECT (){
 	#
 	# Capture first incoming argument as SSID
 	#
 	local ESSID=$1
 
 	#
 	# Kill previous instances of wpa_supplicant to stop other instances
 	# wpa_supplicant fighting several different AP's
 	# Kill based on
 	# ref: http://thegeekstuff.com/2011/10/grep-or-and-not-operators
 	# and
 	# http://stackoverflow.com/questions/3510673/find-and-kill-a-\
 	# process-in-one-line-using-bash-and-regex
 	#
 	# Release dhcp ip's and bring down the interface
 	#
 	kill $(ps aux | grep -E '[w]pa_supplicant.*\'$INT'' |  awk '{print $2}') 2>/dev/null | xargs
 	dhclient $INT -r
 	ifconfig $INT down
 
 	#
 	# Assign new credentials to config file
 	#
 	iwconfig $INT mode managed essid "$ESSID"
 	printf "Configured interface $INT; Config file is $ESSID\n"
 	ifconfig $INT up
 	printf "Interface $INT is up\n"
 	wpa_supplicant -B -Dwext -i$INT -c/etc/wpa_supplicant.conf 2>/dev/null | xargs
 	printf "wpa_supplicant running, sleeping for 15...\n"
 
 	#
 	# Wait to connect before asking for a ip address
 	#
 	sleep 15
 	printf "Running dhclient\n"
 	dhclient $INT
 
 	#
 	# Print current ip for interface to screen
 	#
 	ifconfig $INT | grep inet
 
 	#
 	# Check if internet is available and print status to screen
 	#
 	sleep 5
 	PINGCHECK
 	if [ $INET_AVAIL -eq 1 ]; then
 		printf "Internet is available on this connection\n"
 	else
 		printf "Internet is unavailable on this connection\n"
 	fi
 
 	if [ $RANDOM_CONF_MODE -eq 1 ]; then
-# Check if RANDOM_CONF_MODE is selected and/or config file specified, routes to correct function set
+
 	fi
 
 	exit 0
 }
 
 ########################################################################
 ######################## START HERE ####################################
 
 #
 # Call check args function to check the command line argument supplied are valid.
 #
 CHECK_ARGS "$@"
 
 #
 # Check if RANDOM_CONF_MODE is selected and/or config file specified,
 # routes to correct function set
 # with file name arguments or no arguments depending on what is specified.
 #
 if [ $RANDOM_CONF_MODE -eq 1 ]; then
 	if [ "$CONF_FILE" ]; then
 		RANDOM_FIRST_RUN=1
 		RANDOM_CONF "$CONF_FILE"
 	else
 	RANDOM_CONF
 	fi
 else
 	if [ "$CONF_FILE" ]; then
 		READ_SAVED "$CONF_FILE"
 	else
 		READ_SAVED
 	fi
 fi
 
 exit 0