# Copyright (c) 2004-2005 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2
# $Header$

# Contributed by Roy Marples (uberlord@gentoo.org)

# char* macchanger_provides(void)
#
# Returns a string to change module definition for starting up
macchanger_provides() {
	echo "macchanger"
}

# void macchanger_depend(void)
#
# Sets up the dependancies for the module
macchanger_depend() {
	before interface wireless
}

# bool macchanger_check_installed(void)
#
# Returns 1 if macchanger is installed, otherwise 0
macchanger_check_installed() {
	[[ -x /sbin/macchanger ]] && return 0
	${1:-false} && eerror "For changing MAC addresses, emerge net-analyzer/macchanger"
	return 1
}

# bool macchanger_check_depends(void)
#
# Checks to see if we have the needed functions
macchanger_check_depends() {
	local f

	for f in interface_variable interface_get_mac_address; do
		[[ $( type -t ${f} ) == function ]] && continue
		eerror "macchanger: missing required function ${f}\n"
		return 1
	done

	return 0
}

# bool macchanger_pre_start(char *iface)
#
# Configures the MAC address for iface 
macchanger_pre_start() {
	local iface=${1} mac opts
	local ifvar=$( interface_variable ${1} )

	eval mac=\"\$\{mac_${ifvar}\}\"
	[[ -z ${mac} ]] && return 0

	interface_exists ${iface} true || return 1

	mac=$( echo ${mac} | tr '[:upper:]' '[:lower:]' )
	case "${mac}" in
		# specific mac-addr, i wish there were a shorter way to specify this 
		[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]) opts="${opts} --mac=${mac}" ;;

		# increment MAC address, default macchanger behavior
		increment) opts="${opts}" ;;

		# randomize just the ending bytes
		random-ending) opts="${opts} -e" ;;

		# keep the same kind of physical layer (eg fibre, copper)
		random-samekind) opts="${opts} -a" ;;

		# randomize to any known vendor of any physical layer type
		random-anykind) opts="${opts} -A" ;;

		# fully random bytes
		random-full) opts="${opts} -r" ;;

		# default case is just to pass on all the options
		*) opts="${opts} ${mac}" ;;
	esac

	# The interface needs to be up for macchanger to work most of the time
	interface_down ${iface}

	ebegin "Changing MAC address of ${iface}"
	mac=$( /sbin/macchanger ${opts} ${iface} 2>/dev/null | awk '/Faked MAC:/ { print toupper($3) }' )

	# Sometimes the interface needs to be up ....
	if [[ -z ${mac} ]]; then
		interface_up ${iface}
		mac=$( /sbin/macchanger ${opts} ${iface} 2>/dev/null | awk '/Faked MAC:/ { print toupper($3) }' )
	fi

	if [[ -z ${mac} ]]; then
		eend 1 "Failed to set MAC address"
		return 1
	fi

	eend 0
	eindent
	einfo "changed to ${mac}"
	eoutdent

	return 0 #important
}
