#!/bin/bash
#Copyright 2003 William Stearns <wstearns@pobox.com>
#Released under the GPL.

#ZZZZ Check Me and MyVersion
Me='snort-p2p'
MyVersion='20031125'
#DefaultActions=''

[ -r /etc/firebricks/firebricks.conf ] &&			. /etc/firebricks/firebricks.conf
[ -r /etc/firebricks/$Me.conf ] &&				. /etc/firebricks/$Me.conf
[ -r ${FBLibDir:-'/usr/lib/firebricks/'}/firebrickslib ] &&	. ${FBLibDir:-'/usr/lib/firebricks/'}/firebrickslib
if [ -z "$FBLibVer" ]; then
	echo 'It looks like firebrickslib was not loaded, why?  Exiting' >&2
	exit 1
fi

for OneTask in $Tasks ; do
	case "$OneTask" in
	link)
		$IptablesBin -N $Me >/dev/null 2>&1
#ZZZZ try to restrict the following three to only send down what the chain needs to inspect.
		$IptablesBin $AppIn INPUT -i \! lo						-j $Me
		$IptablesBin $AppIn FORWARD							-j $Me
		$IptablesBin $AppIn OUTPUT							-j $Me
		;;
	unlink)
#ZZZZ Make the same changes as above (such as "-p tcp"), but if you cut and paste, note "$AppIn" is now "-D"
		$IptablesBin -D INPUT -i \! lo							-j $Me
		$IptablesBin -D FORWARD								-j $Me
		$IptablesBin -D OUTPUT								-j $Me
		$IptablesBin -X $Me >/dev/null 2>&1
		;;
	create)
		echo "Starting $Me" >&2
		FlushOrNewChain $Me


		LogAs="SID549"		$Ipt -A $Me -p tcp --dport 8888 -m string --string '""'	$Tail	# '"P2P napster login"' classtype:policy-violation sid:549
		LogAs="SID550"		$Ipt -A $Me -p tcp --dport 8888 -m string --string '""'	$Tail	# '"P2P napster new user login"' classtype:policy-violation sid:550
		LogAs="SID551"		$Ipt -A $Me -p tcp --dport 8888 -m string --string '"Ë"'	$Tail	# '"P2P napster download attempt"' classtype:policy-violation sid:551
		LogAs="SID561"		$Ipt -A $Me -p tcp --dport 6699 -m state --state ESTABLISHED -m string --string '".mp3"'	$Tail	# '"P2P Napster Client Data"' nocase-ignored classtype:policy-violation sid:561
		LogAs="SID561"		$Ipt -A $Me -p tcp --sport 6699 -m state --state ESTABLISHED -m string --string '".mp3"'	$Tail	# '"P2P Napster Client Data"' nocase-ignored classtype:policy-violation sid:561
		LogAs="SID563"		$Ipt -A $Me -p tcp --dport 6666 -m state --state ESTABLISHED -m string --string '".mp3"'	$Tail	# '"P2P Napster Client Data"' nocase-ignored classtype:policy-violation sid:563
		LogAs="SID563"		$Ipt -A $Me -p tcp --sport 6666 -m state --state ESTABLISHED -m string --string '".mp3"'	$Tail	# '"P2P Napster Client Data"' nocase-ignored classtype:policy-violation sid:563
		LogAs="SID564"		$Ipt -A $Me -p tcp --dport 5555 -m state --state ESTABLISHED -m string --string '".mp3"'	$Tail	# '"P2P Napster Client Data"' nocase-ignored classtype:policy-violation sid:564
		LogAs="SID564"		$Ipt -A $Me -p tcp --sport 5555 -m state --state ESTABLISHED -m string --string '".mp3"'	$Tail	# '"P2P Napster Client Data"' nocase-ignored classtype:policy-violation sid:564
		LogAs="SID565"		$Ipt -A $Me -p tcp --dport 8875 -m state --state ESTABLISHED -m string --string '"anon@napster.com"'	$Tail	# '"P2P Napster Server Login"' classtype:policy-violation sid:565
		LogAs="SID565"		$Ipt -A $Me -p tcp --sport 8875 -m state --state ESTABLISHED -m string --string '"anon@napster.com"'	$Tail	# '"P2P Napster Server Login"' classtype:policy-violation sid:565
		LogAs="SID1383"		$Ipt -A $Me -p tcp --dport 1214 -m string --string '"GET "'	$Tail	# '"P2P Fastrack (kazaa/morpheus) GET request"' url,www.musiccity.com/technology.htm url,www.kazaa.com classtype:policy-violation sid:1383
		LogAs="SID1699"		$Ipt -A $Me -p tcp -m string --string '"GET"' --string '"UserAgent: KazaaClient"'	$Tail	# '"P2P Fastrack (kazaa/morpheus) traffic"' url,www.kazaa.com classtype:policy-violation sid:1699
		LogAs="SID2180"		$Ipt -A $Me -p tcp -m string --string '"GET"' --string '"/announce"' --string '"info_hash="' --string '"event=started"'	$Tail	# '"P2P BitTorrent announce request"' classtype:policy-violation sid:2180
		LogAs="SID2181"		$Ipt -A $Me -p tcp --dport 6881:6889 -m string --string '"BitTorrent protocol"'	$Tail	# '"P2P BitTorrent transfer"' classtype:policy-violation sid:2181


		;;
	destroy)
		echo "Stopping $Me" >&2
		DestroyChain $Me
		;;
	renamechain)
		TempChain="$Me-$RANDOM"
		echo "Replacing existing rules in $Me with new rules" >&2
		$IptablesBin -E $Me $TempChain
		;;
	replacelinks)
		if [ -z "$TempChain" ]; then
			echo "No temporary chain to relink in $Me replacelinks, replace operation incomplete." >&2
		elif ! $IptablesBin -L $Me -n >/dev/null 2>&1 ; then
			echo "No $Me chain in $Me, replace operation incomplete." >&2
		elif ! $IptablesBin -L $TempChain -n >/dev/null 2>&1 ; then
			echo "No $TempChain chain in $Me, replace operation incomplete." >&2
		elif [ "`$IptablesBin -L INPUT -n --line-numbers | grep $TempChain | wc -l`" -ne 1 ]; then
			echo "Too few/many references to $TempChain in INPUT in $Me replacelinks, replace operation incomplete." >&2
		elif [ "`$IptablesBin -L FORWARD -n --line-numbers | grep $TempChain | wc -l`" -ne 1 ]; then
			echo "Too few/many references to $TempChain in FORWARD in $Me replacelinks, replace operation incomplete." >&2
		elif [ "`$IptablesBin -L OUTPUT -n --line-numbers | grep $TempChain | wc -l`" -ne 1 ]; then
			echo "Too few/many references to $TempChain in OUTPUT in $Me replacelinks, replace operation incomplete." >&2
		else
#ZZZZ Place the same criteria you used in link/unlink above in the following three lines.
#ZZZZ Criteria should go just in front of "-j $Me"
			$IptablesBin -R INPUT `$IptablesBin -L INPUT -n --line-numbers | grep $TempChain | awk '{print $1}'` -i \! lo		-j $Me
			$IptablesBin -R FORWARD `$IptablesBin -L FORWARD -n --line-numbers | grep $TempChain | awk '{print $1}'`		-j $Me
			$IptablesBin -R OUTPUT `$IptablesBin -L OUTPUT -n --line-numbers | grep $TempChain | awk '{print $1}'`			-j $Me
			DestroyChain $TempChain
			unset TempChain
		fi
		;;
	status)
		if $IptablesBin -L $Me -n >/dev/null 2>&1 ; then
			echo "$Me created" >&2
		else
			echo "$Me destroyed" >&2
		fi
		;;
	version)
		echo "$Me $MyVersion, firebrickslib $FBLibVer" >&2
		;;
	help)
		DefaultHelp
#ZZZZ Please change the text to appropriate help text for this module.  You should
#ZZZZ cover what the module does, if it's generally safe to use, and under what
#ZZZZ conditions it should not be used.  Please replace the lines between the two
#ZZZZ EOTEXT lines with your own.
		cat <<EOTEXT >&2
	The $Me module puts in some blocks for fragmented icmp packets
(illegal) and address mask and timestamp requests and replies.  At best,
these are uncommon and are used in network mapping.  These rules should
be safe to use on any network.
EOTEXT
		;;
	*)
		echo "Unknown action $Action in $Me, no action taken." >&2
		;;
	esac
done