#/bin/bash # v0.6 # By Brielle Bruns # URL: http://www.sosdg.org/freestuff/firewall # License: GPLv3 BASEDIR=/etc/firewall-sosdg TWEAKS=$BASEDIR/tweaks #BASEDIR=`pwd` . $BASEDIR/options $IPTABLES --flush &>/dev/null $IPTABLES -F OUTPUT &>/dev/null $IPTABLES -F PREROUTING &>/dev/null $IPTABLES -F POSTROUTING &>/dev/null if [ $NAT ]; then $IPTABLES -F -t nat &>/dev/null fi $IPTABLES -F -t raw &>/dev/null $BASEDIR/prerun $IPTABLES -A INPUT -i lo -j ACCEPT $IPTABLES -A OUTPUT -o lo -j ACCEPT echo -n "Adding trusted IP: " 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" echo -n "Adding blocked IPs: " if [ $BLOCKEDIP ]; then for i in `grep -v "\#" $BLOCKEDIP`; do echo -n "$i" $IPTABLES -A INPUT -s $i -j DENY $IPTABLES -A OUTPUT -d $i -j DENY done fi echo -ne "\n" if [ $CLAMPMSS ]; then echo "Clamping MSS to PMTU..." iptables -A FORWARD -p tcp --tcp-flags SYN,RST SYN -j TCPMSS \ --clamp-mss-to-pmtu iptables -A OUTPUT -p tcp --tcp-flags SYN,RST SYN -j TCPMSS \ --clamp-mss-to-pmtu #$IPTABLES -t mangle -o $CLAMPMSS -A FORWARD -p tcp \ # --tcp-flags SYN,RST SYN -m tcpmss --mss 1400:1536 \ # -j TCPMSS --clamp-mss-to-pmtu #$IPTABLES -t mangle -o $CLAMPMSS -A OUTPUT -p tcp \ # --tcp-flags SYN,RST SYN -m tcpmss --mss 1400:1536 \ # -j TCPMSS --clamp-mss-to-pmtu fi echo -en "\n" $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 [ $CONNTRACK ]; then $IPTABLES -A INPUT -i lo -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 INPUT -m state --state INVALID -j DROP $IPTABLES -A OUTPUT -m state --state RELATED,ESTABLISHED -j ACCEPT $IPTABLES -A OUTPUT -m state --state NEW -j ACCEPT fi echo -n "Adding allowed port: " for i in $TCPPORTS; do echo -n "TCP/$i " $IPTABLES -A INPUT -p tcp --dport $i -j ACCEPT done for i in $UDPPORTS; do echo -n "UDP/$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 echo -en "\n" echo -n "Adding allowed protocols: " for i in $ALLOWEDPROTO; do echo -n "$i " $IPTABLES -A INPUT -p $i -j ACCEPT $IPTABLES -A OUTPUT -p $i -j ACCEPT done echo -en "\n" 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 echo -n "Adding route: " if [ $ROUTING ]; then for i in `grep -v "\#" $ROUTING`; do ROUTE=( ${i//:/ } ) FWINT1=${ROUTE[0]} FWINT2=${ROUTE[2]} FWIP1=${ROUTE[1]} FWIP2=${ROUTE[3]} echo 1 > /proc/sys/net/ipv4/conf/$FWINT1/forwarding echo 1 > /proc/sys/net/ipv4/conf/$FWINT2/forwarding $IPTABLES -A FORWARD -i $FWINT1 -o $FWINT2 \ -s $FWIP1 -d $FWIP2 -j ACCEPT if [ ${ROUTE[4]} == "1" ]; then echo -n "$FWINT1:$FWIP1<->$FWINT2:$FWIP2} " $IPTABLES -A FORWARD -o $FWINT1 -i $FWINT2 \ -d $FWIP1 -s $FWIP2 -j ACCEPT else echo -n "$FWINT1:$FWIP1->$FWINT2:$FWIP2} " fi done fi echo -ne "\n" if [ $PORTFW ] && [ $NAT ]; then for i in `grep -v "\#" $PORTFW`; do PORTADD=( ${i//:/ } ) echo "Adding port forward for ext port ${PORTADD[0]}/${PORTADD[1]} to ${PORTADD[2]}:${PORTADD[3]}" $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 done fi if [ $LANDHCPSERVER ]; then $IPTABLES -A INPUT -i $INTIF -s 0.0.0.0 -j ACCEPT fi if [ $NAT ]; then for i in $NATRANGE; do $IPTABLES -A POSTROUTING -t nat -s $i -o $NATEXTIF -j SNAT --to-source $NATEXTIP done fi $IPTABLES --policy INPUT ACCEPT $IPTABLES --policy OUTPUT ACCEPT $IPTABLES --policy FORWARD DROP 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 echo -n "Adding trusted IPv6: " $IP6TABLES -A INPUT -i lo -j ACCEPT $IP6TABLES -A OUTPUT -o lo -j ACCEPT for i in $IPV6TRUSTED; do echo -n "$i " $IP6TABLES -A INPUT -s $i -j ACCEPT $IP6TABLES -A OUTPUT -d $i -j ACCEPT done echo -ne "\n" echo -n "Adding allowed IPv6 port: " for i in $IPV6TCP; do echo -n "TCP/$i " $IP6TABLES -A INPUT -p tcp --dport $i -j ACCEPT done for i in $IPV6UDP; do echo -n "UDP/$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 echo -en "\n" if [ $IPV6ROUTEDCLIENTBLOCK ]; then $IP6TABLES -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT $IP6TABLES -A FORWARD -m state --state ESTABLISHED,RELATED -j ACCEPT $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 [ $IPV6FORWARDRANGE ]; then for i in $IPV6FORWARDRANGE; do $IP6TABLES -A FORWARD -s $i -j ACCEPT $IP6TABLES -A FORWARD -d $i -j ACCEPT done fi if [ $IPV6BLOCKINCOMING ]; then $IP6TABLES -A INPUT -p tcp --syn -j DROP $IP6TABLES -A INPUT -p udp -j DROP fi 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