#/bin/sh
# v0.9.4
# By Brielle Bruns <bruns@2mbit.com>
# URL: http://www.sosdg.org/freestuff/firewall
# License: GPLv3
#
#    Copyright (C) 2009 - 2010  Brielle Bruns
#    Copyright (C) 2009 - 2010  The Summit Open Source Development Group
#
#    This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation, either version 3 of the License, or
#    (at your option) any later version.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#    You should have received a copy of the GNU General Public License
#    along with this program.  If not, see <http://www.gnu.org/licenses/>.


echo "=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
 Firewall/SOSDG v0.9.4
 Brielle Bruns <bruns@2mbit.com>
 http://www.sosdg.org/freestuff/firewall
 This program comes with ABSOLUTELY NO WARRANTY.
 This is free software, and you are welcome to 
 redistribute it under certain conditions.
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-="

BASEDIR=/etc/firewall-sosdg
TWEAKS=$BASEDIR/tweaks
#BASEDIR=`pwd`

. $BASEDIR/options
. $BASEDIR/include/functions


$IPTABLES --flush &>/dev/null
$IPTABLES -F OUTPUT &>/dev/null
$IPTABLES -F PREROUTING &>/dev/null
$IPTABLES -F POSTROUTING &>/dev/null
$IPTABLES -F -t mangle &>/dev/null
if [ $NAT ]; then
	$IPTABLES -F -t nat &>/dev/null
fi
$IPTABLES -F -t raw &>/dev/null
if [ -s "$BASEDIR/include/ipv4_custom_flush" ]; then
	display_c YELLOW "Loading custom flush rules..."
	. "$BASEDIR/include/ipv4_custom_flush"
fi

$BASEDIR/prerun

$IPTABLES -A INPUT -i lo -j ACCEPT
$IPTABLES -A OUTPUT -o lo -j ACCEPT

if [ -s "$BASEDIR/include/ipv4_custom_trust" ]; then
	display_c YELLOW "Loading custom trust rules..."
	. "$BASEDIR/include/ipv4_custom_trust"
fi

if [ "$TRUSTEDIP" ]; then
	display_c YELLOW "Adding trusted IP: " N
	for i in $TRUSTEDIP; do
		echo -n "$i "
		$IPTABLES -A INPUT -s $i -j ACCEPT
		$IPTABLES -A OUTPUT -d $i -j ACCEPT
	done
	echo -ne "\n"
fi

if [ -s "$BASEDIR/include/ipv4_custom_blockip" ]; then
	display_c YELLOW "Loading custom ip block rules..."
	. "$BASEDIR/include/ipv6_custom_blockip"
fi

if [ $BLOCKEDIP ]; then
	display_c YELLOW "Adding blocked IPs: " N
	for i in `grep -v "\#" $BLOCKEDIP`; do
		echo -n "$i "
		$IPTABLES -A INPUT -s $i -j DROP
		$IPTABLES -A OUTPUT -d $i -j DROP
	done
echo -ne "\n"
fi

if [ "$STRIPECN" ]; then
	display_c YELLOW "Stripping ECN off of TCP packets to " N
	for i in $STRIPECN; do
		echo -en "$i "
		$IPTABLES -A PREROUTING -t mangle -p tcp -d $i -j ECN \
			--ecn-tcp-remove
	done
echo -ne "\n"
fi

if [ -s "$BASEDIR/include/ipv4_custom_mssclamp" ]; then
	display_c YELLOW "Loading custom MSS Clamp rules..."
	. "$BASEDIR/include/ipv4_custom_mssclamp"
fi

if [ "$CLAMPMSS" ]; then
	display_c YELLOW "Clamping MSS to PMTU..."
	for i in $CLAMPMSS; do
		$IPTABLES -A FORWARD -p tcp --tcp-flags SYN,RST SYN -j TCPMSS \
			--clamp-mss-to-pmtu -o $i -m tcpmss --mss 1400:1536
		$IPTABLES -A OUTPUT -p tcp --tcp-flags SYN,RST SYN -j TCPMSS \
			--clamp-mss-to-pmtu -o $i -m tcpmss --mss 1400:1536
		# This is necessary to make sure that PMTU works
		$IPTABLES -A OUTPUT -p icmp --icmp-type time-exceeded \
			-o $i -j ACCEPT
		$IPTABLES -A INPUT -p icmp --icmp-type time-exceeded \
			-i $i -j ACCEPT
		$IPTABLES -A OUTPUT -p icmp --icmp-type fragmentation-needed \
			-o $i -j ACCEPT
		$IPTABLES -A INPUT -p icmp --icmp-type fragmentation-needed \
			-i $i -j ACCEPT
	done
echo -en "\n"
fi

$IPTABLES -A INPUT -j DROP -p udp --dport domain -m u32 --u32 \
"0>>22&0x3C@12>>16=1&&0>>22&0x3C@20>>24=0&&0>>22&0x3C@21=0x00020001"

if [ -s "$BASEDIR/include/ipv4_custom_conntrack" ]; then
	display_c YELLOW "Loading custom conntrack rules..."
	. "$BASEDIR/include/ipv4_custom_conntrack"
fi

if [ $CONNTRACK ]; then
	$IPTABLES -A INPUT -m state --state NEW -j ACCEPT
	$IPTABLES -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
	$IPTABLES -A FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT
	$IPTABLES -A FORWARD -m state --state NEW -j ACCEPT
	$IPTABLES -A OUTPUT -m state --state RELATED,ESTABLISHED -j ACCEPT 
	$IPTABLES -A OUTPUT -m state --state NEW -j ACCEPT
	$IPTABLES -A INPUT -m state --state INVALID -j DROP
	$IPTABLES -A OUTPUT -m state --state INVALID -j DROP
	$IPTABLES -A FORWARD -m state --state INVALID -j DROP
fi

if [ -s "$BASEDIR/include/ipv4_custom_blockoutports" ]; then
	display_c YELLOW "Loading custom blocked outbound port rules..."
	. "$BASEDIR/include/ipv4_custom_blockoutports"
fi

if [ "$BLOCKTCPPORTS" ] || [ "$BLOCKUDPPORTS" ]; then
	display_c YELLOW "Blocking outbound port: " N

	if  [ "$BLOCKTCPPORTS" ]; then
		for i in $BLOCKTCPPORTS; do
			echo -en "\E[35mTCP\E[37m/\E[32m$i "
			$IPTABLES -A OUTPUT -p tcp --dport $i --syn -j DROP
			if [ "$NATRANGE" ]; then
				for src in $NATRANGE; do
					$IPTABLES -A FORWARD -p tcp -s $src --dport $i --syn -j DROP
				done
			fi
		done
	fi
	if  [ "$BLOCKUDPPORTS" ]; then
		for i in $BLOCKUDPPORTS; do
			echo -en "\E[34mUDP\E[37m/\E[32m$i "
			$IPTABLES -A OUTPUT -p udp --dport $i -j DROP
			if [ "$NATRANGE" ]; then
				for src in $NATRANGE; do
					$IPTABLES -A FORWARD -p udp -s $src --dport $i -j DROP
				done
			fi
		done
	fi
	echo -en "\n"
fi

if [ -s "$BASEDIR/include/ipv4_custom_allowedports" ]; then
	display_c YELLOW "Loading custom allowed port rules..."
	. "$BASEDIR/include/ipv4_custom_allowedports"
fi

if [ "$TCPPORTS" ] || [ "$UDPPORTS" ]; then
	display_c YELLOW "Adding allowed port: " N

	if [ "$TCPPORTS" ]; then
		for i in $TCPPORTS; do
			echo -en "\E[35mTCP\E[37m/\E[32m$i "
			$IPTABLES -A INPUT -p tcp --dport $i -j ACCEPT
		done
	fi
	if [ "$UDPPORTS" ]; then
		for i in $UDPPORTS; do
			echo -en "\E[34mUDP\E[37m/\E[32m$i "
			#$IPTABLES -A INPUT -p udp --dport $i -j ACCEPT
			$IPTABLES -A OUTPUT -p udp --sport 1:65535 --dport $i -j ACCEPT
        		$IPTABLES -A INPUT -p udp --dport $i --sport 1:65535 -j ACCEPT
			$IPTABLES -A INPUT -p udp --sport $i --dport 1:65535 -j ACCEPT
		done
	fi
	reset_color
fi



if [ -s "$BASEDIR/include/ipv4_custom_proto" ]; then
	display_c YELLOW "Loading custom protocol rules..."
	. "$BASEDIR/include/ipv4_custom_proto"
fi

if [ "$ALLOWEDPROTO" ]; then
	display_c YELLOW "Adding allowed protocols: " N
	for i in $ALLOWEDPROTO; do
		echo -n "$i "
		$IPTABLES -A INPUT -p $i -j ACCEPT
		$IPTABLES -A OUTPUT -p $i -j ACCEPT
	done
	reset_color
fi


if [ -s "$BASEDIR/include/ipv4_custom_notrack" ]; then
	display_c YELLOW "Loading custom NOTRACK rules..."
	. "$BASEDIR/include/ipv4_custom_notrack"
fi

if [ $CONNTRACK ]; then
	for i in $DONTTRACK; do
		$IPTABLES -t raw -I PREROUTING -s $i -j NOTRACK
		$IPTABLES -t raw -I PREROUTING -d $i -j NOTRACK
		$IPTABLES -t raw -I OUTPUT -s $i -j NOTRACK
		$IPTABLES -t raw -I OUTPUT -d $i -j NOTRACK
	done
fi


if [ -s "$BASEDIR/include/ipv4_custom_routing" ]; then
	display_c YELLOW "Loading custom routing rules..."
	. "$BASEDIR/include/ipv4_custom_routing"
fi

if [ $ROUTING ]; then
	display_c YELLOW "Adding route: " N
	for i in `grep -v "\#" $ROUTING`; do
		ROUTE=( ${i//:/ } )
		FWINT1=${ROUTE[0]}
		FWINT2=${ROUTE[2]}
		FWIP1=${ROUTE[1]}
		FWIP2=${ROUTE[3]}

		if [ -e "/proc/sys/net/ipv4/conf/$FWINT1/forwarding" ]; then
			echo 1 > /proc/sys/net/ipv4/conf/$FWINT1/forwarding
		fi
		if [ -e "/proc/sys/net/ipv4/conf/$FWINT2/forwarding" ]; then
			echo 1 > /proc/sys/net/ipv4/conf/$FWINT2/forwarding
		fi
		$IPTABLES -A FORWARD -i $FWINT1 -o $FWINT2 \
			-s $FWIP1 -d $FWIP2 -j ACCEPT
		if [ ${ROUTE[4]} == "1" ]; then
			echo -en "\E[35m$FWINT1\E[37m:$FWIP1<->\E[34m$FWINT2\E[37m:$FWIP2 "
 			$IPTABLES -A FORWARD -o $FWINT1 -i $FWINT2 \
				-d $FWIP1 -s $FWIP2 -j ACCEPT
		else
			echo -n "$FWINT1:$FWIP1->$FWINT2:$FWIP2 "
	fi
	done
echo -ne "\n"
fi


if [ -s "$BASEDIR/include/ipv4_custom_portforward" ]; then
	display_c YELLOW "Loading custom port forwarding rules..."
	. "$BASEDIR/include/ipv4_custom_portforward"
fi

if [ $PORTFW ] && [ $NAT ]; then
	display_c YELLOW "Adding port forward for: " N
	for i in `grep -v "\#" $PORTFW`; do
		PORTADD=( ${i//:/ } )
		$IPTABLES -A PREROUTING -t nat -i $NATEXTIF -p ${PORTADD[1]} \
			--dport ${PORTADD[0]} -j DNAT --to \
			${PORTADD[2]}:${PORTADD[3]}
		$IPTABLES -A INPUT -p ${PORTADD[1]} -m state --state NEW \
			--dport ${PORTADD[0]} -i $NATEXTIF -j ACCEPT
		echo -en "\E[32m${PORTADD[0]}\E[37m/\E[35m${PORTADD[1]}\E[37m->${PORTADD[2]}:${PORTADD[3]} "
	done
echo -ne "\n"
fi

if [ $LANDHCPSERVER ]; then
	#$IPTABLES -A INPUT -i $INTIF -s 0.0.0.0 -j ACCEPT
	$IPTABLES  -I INPUT -i $INTIF -p udp --dport 67:68 --sport \
     67:68 -j ACCEPT

fi


if [ -s "$BASEDIR/include/ipv4_custom_nat" ]; then
	display_c YELLOW "Loading custom nat rules..."
	. "$BASEDIR/include/ipv4_custom_nat"
fi

if [ $NAT ]; then
	if [ $NAT_RANGE ]; then
		display_c YELLOW "Adding NAT rule: " N
		for i in $NAT_RANGE; do
			NAT_RULE=( ${i//:/ } )
			case $NAT_RULE[1] in
			SNAT)
				$IPTABLES -A POSTROUTING -t nat -i ${NAT_RULE[2]} -s ${NAT_RULE[3]} -j SNAT \
					-o ${NAT_RULE[4]} --to-source ${NAT_RULE[5]} 
					display_c PURPLE "SNAT:${NAT_RULE[2]}:${NAT_RULE[3]}->${NAT_RULE[4]}:${NAT_RULE[5]} " N
					;;
			MASQ)
				$IPTABLES -A POSTROUTING -t nat -i ${NAT_RULE[2]} -s ${NAT_RULE[3]} \
					-j MASQUERADE -o ${NAT_RULE[4]}
					display_c PURPLE "MASQ:${NAT_RULE[2]}:${NAT_RULE[3]}->${NAT_RULE[4]} " N
					;;
				*) display_c RED "Invalid NAT rule in NAT_RANGE" ;;
			esac
			$IPTABLES -A OUTPUT -p icmp --icmp-type time-exceeded -o ${NAT_RULE[4]} -j ACCEPT
			$IPTABLES -A OUTPUT -p icmp --icmp-type fragmentation-needed -o ${NAT_RULE[4]} -j ACCEPT
		done
		echo -ne "\n"
	fi			
	#=================
    # This section is going away in 1.0
	for i in $NATRANGE; do
		$IPTABLES -A POSTROUTING -t nat -s $i -o $NATEXTIF -j SNAT --to-source $NATEXTIP
	done
	 This is necessary to make sure that PMTU works
	$IPTABLES -A OUTPUT -p icmp --icmp-type time-exceeded -o $NATEXTIF \
			-j ACCEPT
	$IPTABLES -A OUTPUT -p icmp --icmp-type fragmentation-needed \
			-o $NATEXTIF -j ACCEPT
	#=================
fi

$IPTABLES --policy INPUT ACCEPT
$IPTABLES --policy OUTPUT ACCEPT
$IPTABLES --policy FORWARD DROP


if [ -s "$BASEDIR/include/ipv4_custom_blockincoming" ]; then
	display_c YELLOW "Loading custom incoming blocked rules..."
	. "$BASEDIR/include/ipv4_custom_blockincoming"
fi

if [ $BLOCKINCOMING ]; then
		$IPTABLES -A INPUT -p tcp --syn -j DROP
		$IPTABLES -A INPUT -p udp -j DROP
fi


#================[IPv6]================
if [ $IPV6 ]; then
	$IP6TABLES --flush &>/dev/null
	$IP6TABLES -F OUTPUT &>/dev/null
	$IP6TABLES -F PREROUTING &>/dev/null
	$IP6TABLES -F POSTROUTING &>/dev/null
	if [ -s "$BASEDIR/include/ipv6_custom_flush" ]; then
		display_c YELLOW "Loading custom IPv6 flush rules..."
		. "$BASEDIR/include/ipv6_custom_flush"
	fi

	display_c YELLOW "Adding trusted IPv6: " N

	$IP6TABLES -A INPUT -i lo -j ACCEPT
	$IP6TABLES -A OUTPUT -o lo -j ACCEPT

	if [ -s "$BASEDIR/include/ipv6_custom_trust" ]; then
		display_c YELLOW "Loading custom IPv6 trust rules..."
		. "$BASEDIR/include/ipv6_custom_trust"
	fi
	for i in $IPV6TRUSTED; do
		echo -n "$i "
		$IP6TABLES -A INPUT -s $i -j ACCEPT
		$IP6TABLES -A OUTPUT -d $i -j ACCEPT
	done
	reset_color

	if [ -s "$BASEDIR/include/ipv6_custom_mssclamp" ]; then
		display_c YELLOW "Loading custom IPv6 MSS Clamp rules..."
		. "$BASEDIR/include/ipv6_custom_mssclamp"
	fi

	if [ "$CLAMPMSSIPV6" ]; then
		display_c YELLOW "Clamping IPV6 MSS to PMTU..."
		for i in $CLAMPMSSIPV6; do
			$IP6TABLES -A FORWARD -p tcp --tcp-flags SYN,RST SYN \
			-j TCPMSS --clamp-mss-to-pmtu -o $i -m tcpmss \
			--mss 1280:1536
			$IP6TABLES -A OUTPUT -p tcp --tcp-flags SYN,RST SYN \
			-j TCPMSS --clamp-mss-to-pmtu -o $i -m tcpmss \
			--mss 1280:1536
			# This is necessary to make sure that PMTU works
			$IP6TABLES -A OUTPUT -p icmpv6 --icmpv6-type time-exceeded \
			-o $i -j ACCEPT
			$IP6TABLES -A INPUT -p icmpv6 --icmpv6-type time-exceeded \
			-i $i -j ACCEPT
			$IP6TABLES -A OUTPUT -p icmpv6 --icmpv6-type packet-too-big \
			-o $i -j ACCEPT
			$IP6TABLES -A INPUT -p icmpv6 --icmpv6-type packet-too-big \
			-i $i -j ACCEPT
		done
	fi

	if [ -s "$BASEDIR/include/ipv6_custom_blockoutports" ]; then
		display_c YELLOW "Loading custom IPv6 blocked outbound port rules..."
		. "$BASEDIR/include/ipv6_custom_blockoutports"
	fi
	if [ "$BLOCKIPV6TCPPORTS" ] || [ "$BLOCKIPV6UDPPORTS" ]; then
		display_c YELLOW "Blocking outbound port: " N
		if [ "$BLOCKIPV6TCPPORTS" ]; then
			for i in $BLOCKIPV6TCPPORTS; do
				echo -en "\E[35mTCP\E[37m/\E[32m$i "
				$IP6TABLES -A OUTPUT -p tcp --dport $i --syn -j DROP
			done
		fi
		if [ "$BLOCKIPV6UDPPORTS" ]; then
			for i in $BLOCKIPV6UDPPORTS; do
				echo -en "\E[34mUDP\E[37m/\E[32m$i "
				$IP6TABLES -A OUTPUT -p udp --dport $i -j DROP
			done
		fi
		reset_color
	fi

	if [ -s "$BASEDIR/include/ipv6_custom_allowedports" ]; then
		display_c YELLOW "Loading custom IPv6 allowed port rules..."
		. "$BASEDIR/include/ipv6_custom_allowedports"
	fi
	if [ "$IPV6TCP" ] || [ "$IPV6UDP" ]; then
		display_c YELLOW "Adding allowed IPv6 port: " N

		if [ "$IPV6TCP" ]; then
			for i in $IPV6TCP; do
				echo -en "\E[35mTCP\E[37m/\E[32m$i "
				$IP6TABLES -A INPUT -p tcp --dport $i -j ACCEPT
			done
		fi

		if [ "$IPV6UDP" ]; then
			for i in $IPV6UDP; do
				echo -en "\E[34mUDP\E[37m/\E[32m$i "
				$IP6TABLES -A OUTPUT -p udp --sport 1:65535 --dport $i -j ACCEPT
	        		$IP6TABLES -A INPUT -p udp --dport $i --sport 1:65535 -j ACCEPT
        			$IP6TABLES -A INPUT -p udp --sport $i --dport 1:65535 -j ACCEPT
			done
		fi
		reset_color
	fi
	fi

	if [ -s "$BASEDIR/include/ipv6_custom_conntrack" ]; then
		display_c YELLOW "Loading custom IPv6 conntrack rules..."
		. "$BASEDIR/include/ipv6_custom_conntrack"
	fi

	if [ $IPV6ROUTEDCLIENTBLOCK ]; then
		$IP6TABLES -A INPUT -m state --state NEW -j ACCEPT
		$IP6TABLES -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
		$IP6TABLES -A FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT
		$IP6TABLES -A FORWARD -m state --state NEW -j ACCEPT
		$IP6TABLES -A OUTPUT -m state --state RELATED,ESTABLISHED -j ACCEPT 
		$IP6TABLES -A OUTPUT -m state --state NEW -j ACCEPT
		$IP6TABLES -A INPUT -m state --state INVALID -j DROP
		$IP6TABLES -A OUTPUT -m state --state INVALID -j DROP
		$IP6TABLES -A FORWARD -m state --state INVALID -j DROP
		$IP6TABLES -A FORWARD -i $IPV6INT -o $IPV6LAN -p tcp --syn -j DROP
		$IP6TABLES -A INPUT -i $IPV6INT -p tcp --syn -j DROP
		$IP6TABLES -A INPUT -i $IPV6INT -p udp ! --dport 32768:65535 -j DROP
		$IP6TABLES -A FORWARD -i $IPV6INT -o $IPV6LAN -p udp ! --dport 32768:65535 -j DROP
	fi
	


	if [ -s "$BASEDIR/include/ipv6_custom_routing" ]; then
		display_c YELLOW "Loading custom IPv6 routing rules..."
		. "$BASEDIR/include/ipv6_custom_routing"
	fi
	if [ "$IPV6FORWARDRANGE" ]; then
		for i in $IPV6FORWARDRANGE; do
			$IP6TABLES -A FORWARD -s $i -j ACCEPT
			$IP6TABLES -A FORWARD -d $i -j ACCEPT
		done
	fi
	
	if [ -s "$BASEDIR/include/ipv6_custom_blockincoming" ]; then
		display_c YELLOW "Loading custom IPv6 incoming blocked port rules..."
		. "$BASEDIR/include/ipv6_custom_blockincoming"
	fi
	if [ $IPV6BLOCKINCOMING ]; then
		$IP6TABLES -A INPUT -p tcp --syn -j DROP
		$IP6TABLES -A INPUT -p udp -j DROP
	fi

if [ $TWEAKS ]; then
	for i in `grep -v "\#" $TWEAKS`; do
		PROCOPT=( ${i//=/ } )
		echo ${PROCOPT[1]} > /proc/sys/net/${PROCOPT[0]} &>/dev/null
	done
fi

$BASEDIR/postrun