#!/bin/bash
#
# test-wireless-ap
#
# Usage:
#   test-wireless-ap [--timeout=TIMEOUT] IFACE [AP_MAC_ADDRESS] [IWCONFIG_ARG]...
#
# This tests whether the wireless card can associate to an access
# point using the given iwconfig argument pairs
#     essid ESSID
#     key 123456
# and so on.
#
# Licensed under the GNU GPL.  See /usr/share/common-licenses/GPL.
#
# History
# Nov 2003: Modified by Thomas Hood and Klaus Wacker
# July 2003: Modified by Thomas Hood to support Aironet cards
# June 2003: Modified by John Fettig <jfettig@uiuc.edu>
# Jan 2003:  Derived from testssid by Andrew McMillan <awm@debian.org>
#            Written by Thomas Hood <jdthood@yahoo.co.uk>

set -o errexit   # -e
set -o noglob    # -f

MYNAME="$(basename $0)"
PATH=/sbin:/bin

report_err() { echo "${MYNAME}: Error: $*" >&2 ; }

do_sleep() { LANG=C sleep "$@" ; }

is_ethernet_mac()
{
	[ "$1" ] && [ ! "${1/[0-9A-F][0-9A-F]:[0-9A-F][0-9A-F]:[0-9A-F][0-9A-F]:[0-9A-F][0-9A-F]:[0-9A-F][0-9A-F]:[0-9A-F][0-9A-F]/}" ]
}

extract_ESSID()
{
	while [ "$1" ] ; do
		[ "$1" != "essid" ] || { ESSID="$2" ; return ; }
		shift
	done
}

TIMEOUT=3
case "$1" in
	--timeout) TIMEOUT="$2" ; shift 2 ;;
	--timeout=*) TIMEOUT="${1#--timeout=}" ; shift ;;
esac

IFACE="$1"
shift
[ "$IFACE" ] || { report_err "Interface not specified.  Exiting." ; exit 1 ; }

if is_ethernet_mac "$1" ; then
	MAC_ADDRESS="$1"
	shift
fi

extract_ESSID "$@"

iwconfig "$IFACE" "$@"
ifconfig "$IFACE" up

for (( TIMELEFT="$TIMEOUT" ; TIMELEFT > 0 ; TIMELEFT-- )) ; do
	(  # Notice that we are in a subshell here so exiting takes us to the end of it
		if [ "$ESSID" ] ; then
			# Check to see if interface ESSID is what we are looking for
			ESSID_OF_INTERFACE="$(iwgetid $IFACE)"
			ESSID_OF_INTERFACE="${ESSID_OF_INTERFACE#*ESSID:}"
			ESSID_OF_INTERFACE="${ESSID_OF_INTERFACE# }"
			ESSID_OF_INTERFACE="${ESSID_OF_INTERFACE#\"}"
			ESSID_OF_INTERFACE="${ESSID_OF_INTERFACE%\"}"
			[ "$ESSID_OF_INTERFACE" = "$ESSID" ] || exit 1
		fi
		# Check for a valid AP MAC address
		APMAC="$(iwgetid $IFACE --ap --scheme)"
		[ "$APMAC" ] || exit 1
		[ "$APMAC" != "FF:FF:FF:FF:FF:FF" ] || exit 1
		[ "$APMAC" != "ff:ff:ff:ff:ff:ff" ] || exit 1
		[ "$APMAC" != "44:44:44:44:44:44" ] || exit 1
		[ "$APMAC" != "00:00:00:00:00:00" ] || exit 1
		exit 0
	)
	if [ "$?" = 0 ] ; then
		ifconfig "$IFACE" down
		[ ! "$MAC_ADDRESS" ] || [ "$APMAC" = "$MAC_ADDRESS" ] || exit 1
		exit 0
	fi
	do_sleep 1
done
ifconfig "$IFACE" down
exit 1
