#! /bin/sh

# Wrapper script for use of the tsocks(8) transparent socksification library
# See the tsocks(1) manpages.

# Copyright (c) 2004, 2006 Peter Palfrader
# Modified by Jacob Appelbaum <jacob@appelbaum.net> April 16th 2006
# Modified by Felix Bechstein <f@ub0r.de> Dec 23th 2007


# Define and ensure we have tsocks
# XXX: what if we don't have which?
TSOCKS="`which tsocks`"
if [ ! -x "$TSOCKS" ]
then
        echo "$0: Can't find tsocks in PATH. Perhaps you haven't installed it?" >&2
        exit 1
fi

# Define TMPDIR
TMPDIR=/tmp/

# Check for any argument list
if [ "$#" = 0 ]
then
        echo "Usage: $0 <port/dev> <command> [<options>...]" >&2
        exit 1
fi

if [ "$#" = 1 ] && ( [ "$1" = "-h" ] || [ "$1" = "--help" ] )
then
        echo "Usage: $0 <port/dev> <command> [<options>...]"
        exit 0
fi

TSOCKS_PORT=$1
shift

if [ "$#" = 0 ]
then
        echo "Usage: $0 <port/dev> <command> [<options>...]" >&2
        exit 1
fi
if [ "$#" = 1 ] && ( [ "$1" = "-h" ] || [ "$1" = "--help" ] )
then
        echo "Usage: $0 <port/dev> <command> [<options>...]"
        exit 0
fi

# generate config file for port/dev $TSOCKS_PORT
if [ -r "${TMPDIR}routify.${TSOCKS_PORT}" ] ; then
	#conf file already generated. we should use that conf
	TSOCKS_CONF_FILE="${TMPDIR}routify.${TSOCKS_PORT}"
fi

if echo test | nc localhost ${TSOCKS_PORT} > /dev/null 2> /dev/null ; then
	if [ -z "$TSOCKS_CONF_FILE" ] ; then
		echo "server = 127.0.0.1" > ${TMPDIR}routify.${TSOCKS_PORT}
		echo "server_port = ${TSOCKS_PORT}" >> ${TMPDIR}routify.${TSOCKS_PORT}
	fi
else
	/sbin/ifconfig | grep -o "^[a-zA-Z][^ ]*" | grep -v ^lo$ > "${TMPDIR}devlist"
	if echo ${TSOCKS_PORT} | grep -f "${TMPDIR}devlist" > /dev/null ; then
		TSOCKS_DEV=${TSOCKS_PORT}
		# found device as arg
		# but no proxy started for this device
		if [ -z "$TSOCKS_CONF_FILE" ] ; then
			TSOCKS_PORT=10080
			while true ; do
				if echo test | nc localhost ${TSOCKS_PORT} > /dev/null 2> /dev/null ; then
					TSOCKS_PORT=$(expr ${TSOCKS_PORT} + 1) # search for free port
				else
					if fgrep "server_port = $TSOCKS_PORT" ${TMPDIR}routify.* > /dev/null 2> /dev/null ; then
						TSOCKS_PORT=$(expr ${TSOCKS_PORT} + 1) # search for free port
					else
						break
					fi
				fi
			done
			# generate conf file
			echo "server = 127.0.0.1" > ${TMPDIR}routify.${TSOCKS_DEV}
	                echo "server_port = ${TSOCKS_PORT}" >> ${TMPDIR}routify.${TSOCKS_DEV}
		else
			# read port from conf file
			TSOCKS_PORT=$(grep server_port ${TMPDIR}routify.${TSOCKS_PORT} | tr -d 'a-zA-Z =#;_')
		fi
		# start nylon on $TSOCKS_DEV to listen on $TSOCKS_PORT
		echo test | nc localhost ${TSOCKS_PORT} 2> /dev/null > /dev/null || \
			nylon -p $TSOCKS_PORT -I $TSOCKS_DEV -P ${TMPDIR}routify.${TSOCKS_DEV}.nylon
		TSOCKS_CONF_FILE="${TMPDIR}routify.${TSOCKS_DEV}"
	else # proxy down
		echo "socket-proxy is down!"
		rm "${TMPDIR}devlist"
		exit 1
	fi
	rm "${TMPDIR}devlist"
fi

	

# Define our tsocks config file
[ -z "$TSOCKS_CONF_FILE" ] && TSOCKS_CONF_FILE="${TMPDIR}routify.${TSOCKS_PORT}"
export TSOCKS_CONF_FILE

# Check that we've got a tsocks config file
if [ -r "$TSOCKS_CONF_FILE" ]
then
	exec tsocks "$@"
	echo "$0: Failed to exec tsocks $@" >&2
	exit 1
else
	echo "$0: Missing tsocks configuration file \"$TSOCKS_CONF_FILE\"." >&2
	exit 1
fi