#!/bin/sh
#
#version 1.0.6 (modified for custom firmwares)
#

THINCLIENTPATH="/tmp" # path of this file
ROOTHOME="/tmp/root" # root's home dir
SSHPATH="/usr/bin/ssh" # path to ssh
KEY="/tmp/fonkey" # private key for fetching the info from the FON server
THINCLIENTOUT="/tmp/.thinclient.sh" # output file

THINCLIENTOUTDEFAULT="33" # default size of the output file

THCLVER="1.0"
CHILLVER="1.0-1"
FONREV="3" # /etc/fon_revision
FIRMWARE="0.6.6" # taken from /etc/banner (without Beta)


USER="openwrt"
SERVER="download.fon.com"
PORT="1937"
FONSIG="$SERVER ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAIEA0zJFtj5NtrVsj8+qG0dtPE8WpHHDpTXp5+d3vvtSS7Hx7vYHyrfN/8PBVrrYOgl4dySY65sGtq34EU04VN4a7xQHSKJBunDUSQ/2Xz+eyo53LCVeFy1zNRCmB6jrFlJQvl5yviLvXmMtOGxG8Z1dfu4qavfGtBxwtwxKPKuiyhs="

# gather information about this machine
WLMAC="$(/usr/sbin/nvram get wl0_hwaddr)" # original: WLMAC="$(nvram get il0macaddr)"
ETMAC="$(/usr/sbin/nvram get et0macaddr)"
MAC=`echo $WLMAC|tr A-Z a-z`

check_env () {
	[ -d "$ROOTHOME/.ssh" ] || mkdir $ROOTHOME/.ssh
	[ -f "$ROOTHOME/.ssh/known_hosts" ] || touch $ROOTHOME/.ssh/known_hosts
	[ `grep -c $SERVER $ROOTHOME/.ssh/known_hosts` = "0" ] && echo $FONSIG >> $ROOTHOME/.ssh/known_hosts
}

exec_cron_mode () {
	check_env
	sleep "$((0x$(head /dev/urandom |hexdump |awk '$2 > 0 {print $2}'|head -n1) % 60))"
	echo "mode='cron' wlmac='$MAC' mac='$ETMAC' fonrev='$FONREV' firmware='$FIRMWARE'" | $SSHPATH -T ${PORT:+ -p $PORT}${KEY:+ -i $KEY} "${USER}@${SERVER}" > $THINCLIENTOUT
	echo "sent: mode='cron' wlmac='$MAC' mac='$ETMAC' fonrev='$FONREV' firmware='$FIRMWARE'"
	exec_check_thinclient
}

exec_start_mode () {
	sleep 60 # make sure WAN is up and crond is running
	check_env
	# disabled due to problems with wan up/down cron erase (DD-WRT), use the DD-WRT cron feature instead (Admin > Management)
	# [ -f "/tmp/crontab" ] || touch /tmp/crontab
	# [ `grep -c thinclient /tmp/crontab` = "0" ] && echo "24,54 * 	*	*	*	root $THINCLIENTPATH/thinclient cron >/dev/null 2>&1 &" >> /tmp/crontab
	echo "mode='start' wlmac='$MAC' mac='$ETMAC' fonrev='$FONREV' firmware='$FIRMWARE' chillver='$CHILLVER' thclver='$THCLVER'" | $SSHPATH -T ${PORT:+ -p $PORT}${KEY:+ -i $KEY} "${USER}@${SERVER}" > $THINCLIENTOUT
	echo "sent: mode='start' wlmac='$MAC' mac='$ETMAC' fonrev='$FONREV' firmware='$FIRMWARE' chillver='$CHILLVER' thclver='$THCLVER'"
	exec_check_thinclient
}

exec_check_thinclient () {
	if [ -f $THINCLIENTOUT ]
	then
		THINSIZE="$(wc -c < $THINCLIENTOUT)"
		if [ $THINSIZE = "0" ]
		then
			echo "Something is wrong, $THINCLIENTOUT is empty"
		elif [ $THINSIZE != "33" ]
		then
			echo "Something is different in $THINCLIENTOUT:"
			cat $THINCLIENTOUT
		else
			echo "$THINCLIENTOUT is the default one, deleted"
			rm $THINCLIENTOUT
		fi
	else
		echo "Something is wrong, $THINCLIENTOUT does not exist!"
	fi
}

case "$1" in
	cron)
		exec_cron_mode
		;;
	start)
		exec_start_mode
		;;
	check)
		exec_check_thinclient
		;;
	*)
		echo "Usage: `basename $0` {cron|start|check}"
		exit
esac