#!/bin/sh . /etc/sysconfig/rc . ${rc_functions} eval $(/usr/local/bin/readhash /var/ipfire/ppp/settings) eval $(/usr/local/bin/readhash /var/ipfire/ethernet/settings) eval $(/usr/local/bin/readhash /var/ipfire/optionsfw/settings) IFACE=`/bin/cat /var/ipfire/red/iface 2> /dev/null | /usr/bin/tr -d '\012'` if [ -f /var/ipfire/red/device ]; then DEVICE=`/bin/cat /var/ipfire/red/device 2> /dev/null | /usr/bin/tr -d '\012'` fi function iptables() { /sbin/iptables --wait "$@" } iptables_init() { # Flush all rules and delete all custom chains iptables -F iptables -t nat -F iptables -t mangle -F iptables -X iptables -t nat -X iptables -t mangle -X # Set up policies iptables -P INPUT DROP iptables -P FORWARD DROP iptables -P OUTPUT ACCEPT # Empty LOG_DROP and LOG_REJECT chains iptables -N LOG_DROP iptables -A LOG_DROP -m limit --limit 10/minute -j LOG iptables -A LOG_DROP -j DROP iptables -N LOG_REJECT iptables -A LOG_REJECT -m limit --limit 10/minute -j LOG iptables -A LOG_REJECT -j REJECT # This chain will log, then DROPs packets with certain bad combinations # of flags might indicate a port-scan attempt (xmas, null, etc) iptables -N PSCAN if [ "$DROPPORTSCAN" == "on" ]; then iptables -A PSCAN -p tcp -m limit --limit 10/minute -j LOG --log-prefix "DROP_TCP Scan " -m comment --comment "DROP_TCP PScan" iptables -A PSCAN -p udp -m limit --limit 10/minute -j LOG --log-prefix "DROP_UDP Scan " -m comment --comment "DROP_UDP PScan" iptables -A PSCAN -p icmp -m limit --limit 10/minute -j LOG --log-prefix "DROP_ICMP Scan " -m comment --comment "DROP_ICMP PScan" iptables -A PSCAN -f -m limit --limit 10/minute -j LOG --log-prefix "DROP_FRAG Scan " -m comment --comment "DROP_FRAG PScan" fi iptables -A PSCAN -j DROP -m comment --comment "DROP_PScan" # New tcp packets without SYN set - could well be an obscure type of port scan # that's not covered above, may just be a broken windows machine iptables -N NEWNOTSYN if [ "$DROPNEWNOTSYN" == "on" ]; then iptables -A NEWNOTSYN -m limit --limit 10/minute -j LOG --log-prefix "DROP_NEWNOTSYN " fi iptables -A NEWNOTSYN -j DROP -m comment --comment "DROP_NEWNOTSYN" # Chain to contain all the rules relating to bad TCP flags iptables -N BADTCP # Don't check loopback iptables -A BADTCP -i lo -j RETURN # Disallow packets frequently used by port-scanners # nmap xmas iptables -A BADTCP -p tcp --tcp-flags ALL FIN,URG,PSH -j PSCAN # Null iptables -A BADTCP -p tcp --tcp-flags ALL NONE -j PSCAN # FIN iptables -A BADTCP -p tcp --tcp-flags ALL FIN -j PSCAN # SYN/RST (also catches xmas variants that set SYN+RST+...) iptables -A BADTCP -p tcp --tcp-flags SYN,RST SYN,RST -j PSCAN # SYN/FIN (QueSO or nmap OS probe) iptables -A BADTCP -p tcp --tcp-flags SYN,FIN SYN,FIN -j PSCAN # NEW TCP without SYN iptables -A BADTCP -p tcp ! --syn -m conntrack --ctstate NEW -j NEWNOTSYN iptables -A INPUT -p tcp -j BADTCP iptables -A FORWARD -p tcp -j BADTCP # Connection tracking chain iptables -N CONNTRACK iptables -A CONNTRACK -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT # Fix for braindead ISP's iptables -A FORWARD -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu # CUSTOM chains, can be used by the users themselves iptables -N CUSTOMINPUT iptables -A INPUT -j CUSTOMINPUT iptables -N CUSTOMFORWARD iptables -A FORWARD -j CUSTOMFORWARD iptables -N CUSTOMOUTPUT iptables -A OUTPUT -j CUSTOMOUTPUT iptables -t nat -N CUSTOMPREROUTING iptables -t nat -A PREROUTING -j CUSTOMPREROUTING iptables -t nat -N CUSTOMPOSTROUTING iptables -t nat -A POSTROUTING -j CUSTOMPOSTROUTING # Guardian (IPS) chains iptables -N GUARDIAN iptables -A INPUT -j GUARDIAN iptables -A FORWARD -j GUARDIAN # Block OpenVPN transfer networks iptables -N OVPNBLOCK for i in INPUT FORWARD; do iptables -A ${i} -j OVPNBLOCK done # OpenVPN transfer network translation iptables -t nat -N OVPNNAT iptables -t nat -A POSTROUTING -j OVPNNAT # IPTV chains for IGMPPROXY iptables -N IPTVINPUT iptables -A INPUT -j IPTVINPUT iptables -N IPTVFORWARD iptables -A FORWARD -j IPTVFORWARD # filtering from GUI iptables -N GUIINPUT iptables -A INPUT -j GUIINPUT iptables -A GUIINPUT -p icmp --icmp-type 8 -j ACCEPT # Accept everything on loopback iptables -N LOOPBACK iptables -A LOOPBACK -i lo -j ACCEPT iptables -A LOOPBACK -o lo -j ACCEPT # Filter all packets with loopback addresses on non-loopback interfaces. iptables -A LOOPBACK -s 127.0.0.0/8 -j DROP iptables -A LOOPBACK -d 127.0.0.0/8 -j DROP for i in INPUT FORWARD OUTPUT; do iptables -A ${i} -j LOOPBACK done # Accept everything connected for i in INPUT FORWARD OUTPUT; do iptables -A ${i} -j CONNTRACK done # trafic from ipsecX/TUN/TAP interfaces, before "-i GREEN_DEV" accept everything iptables -N IPSECINPUT iptables -N IPSECFORWARD iptables -N IPSECOUTPUT iptables -A INPUT -j IPSECINPUT iptables -A FORWARD -j IPSECFORWARD iptables -A OUTPUT -j IPSECOUTPUT iptables -t nat -N IPSECNAT iptables -t nat -A POSTROUTING -j IPSECNAT # localhost and ethernet. iptables -A INPUT -i $GREEN_DEV -m conntrack --ctstate NEW -j ACCEPT ! -p icmp # allow DHCP on BLUE to be turned on/off iptables -N DHCPBLUEINPUT iptables -A INPUT -j DHCPBLUEINPUT # WIRELESS chains iptables -N WIRELESSINPUT iptables -A INPUT -m conntrack --ctstate NEW -j WIRELESSINPUT iptables -N WIRELESSFORWARD iptables -A FORWARD -m conntrack --ctstate NEW -j WIRELESSFORWARD # OpenVPN iptables -N OVPNINPUT iptables -A INPUT -j OVPNINPUT # TOR iptables -N TOR_INPUT iptables -A INPUT -j TOR_INPUT # Jump into the actual firewall ruleset. iptables -N INPUTFW iptables -A INPUT -j INPUTFW iptables -N OUTGOINGFW iptables -A OUTPUT -j OUTGOINGFW iptables -N FORWARDFW iptables -A FORWARD -j FORWARDFW # SNAT rules iptables -t nat -N NAT_SOURCE iptables -t nat -A POSTROUTING -j NAT_SOURCE # RED chain, used for the red interface iptables -N REDINPUT iptables -A INPUT -j REDINPUT iptables -N REDFORWARD iptables -A FORWARD -j REDFORWARD iptables -t nat -N REDNAT iptables -t nat -A POSTROUTING -j REDNAT iptables_red # Custom prerouting chains (for transparent proxy) iptables -t nat -N SQUID iptables -t nat -A PREROUTING -j SQUID # DNAT rules iptables -t nat -N NAT_DESTINATION iptables -t nat -A PREROUTING -j NAT_DESTINATION # upnp chain for our upnp daemon iptables -t nat -N UPNPFW iptables -t nat -A PREROUTING -j UPNPFW iptables -N UPNPFW iptables -A FORWARD -m conntrack --ctstate NEW -j UPNPFW # Apply OpenVPN firewall rules /usr/local/bin/openvpnctrl --firewall-rules # run wirelessctrl /usr/local/bin/wirelessctrl # POLICY CHAIN iptables -N POLICYIN iptables -A INPUT -j POLICYIN iptables -N POLICYFWD iptables -A FORWARD -j POLICYFWD iptables -N POLICYOUT iptables -A OUTPUT -j POLICYOUT /usr/sbin/firewall-policy # read new firewall /usr/local/bin/firewallctrl } iptables_red() { iptables -F REDINPUT iptables -F REDFORWARD iptables -t nat -F REDNAT # PPPoE / PPTP Device if [ "$IFACE" != "" ]; then # PPPoE / PPTP if [ "$DEVICE" != "" ]; then iptables -A REDINPUT -i $DEVICE -j ACCEPT fi if [ "$RED_TYPE" == "PPTP" -o "$RED_TYPE" == "PPPOE" ]; then if [ "$RED_DEV" != "" ]; then iptables -A REDINPUT -i $RED_DEV -j ACCEPT fi fi fi # PPTP over DHCP if [ "$DEVICE" != "" -a "$TYPE" == "PPTP" -a "$METHOD" == "DHCP" ]; then iptables -A REDINPUT -p tcp --source-port 67 --destination-port 68 -i $DEVICE -j ACCEPT iptables -A REDINPUT -p udp --source-port 67 --destination-port 68 -i $DEVICE -j ACCEPT fi # Orange pinholes if [ "$ORANGE_DEV" != "" ]; then # This rule enables a host on ORANGE network to connect to the outside # (only if we have a red connection) if [ "$IFACE" != "" ]; then iptables -A REDFORWARD -i $ORANGE_DEV -o $IFACE -j ACCEPT fi fi if [ "$IFACE" != "" -a -f /var/ipfire/red/active ]; then # DHCP if [ "$RED_DEV" != "" -a "$RED_TYPE" == "DHCP" ]; then iptables -A REDINPUT -p tcp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT iptables -A REDINPUT -p udp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT fi if [ "$METHOD" == "DHCP" -a "$PROTOCOL" == "RFC1483" ]; then iptables -A REDINPUT -p tcp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT iptables -A REDINPUT -p udp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT fi # Outgoing masquerading (don't masqerade IPSEC (mark 50)) iptables -t nat -A REDNAT -m mark --mark 50 -o $IFACE -j RETURN iptables -t nat -A REDNAT -o $IFACE -j MASQUERADE fi # Reload all rules. /usr/local/bin/firewallctrl } # See how we were called. case "$1" in start) boot_mesg "Loading firewall modules into the kernel" modprobe iptable_nat || failed=1 for i in $(find /lib/modules/$(uname -r) -name nf_conntrack*); do modprobe $(basename $i | cut -d. -f1) || failed=1 done for i in $(find /lib/modules/$(uname -r) -name nf_nat*); do modprobe $(basename $i | cut -d. -f1) || failed=1 done (exit ${failed}) evaluate_retval if [ -e /var/ipfire/main/disable_nf_sip ]; then rmmod nf_nat_sip rmmod nf_conntrack_sip rmmod nf_nat_h323 rmmod nf_conntrack_h323 fi boot_mesg "Setting up firewall" iptables_init evaluate_retval # run local firewall configuration, if present if [ -x /etc/sysconfig/firewall.local ]; then /etc/sysconfig/firewall.local start fi ;; reload) boot_mesg "Reloading firewall" iptables_red evaluate_retval # run local firewall configuration, if present if [ -x /etc/sysconfig/firewall.local ]; then /etc/sysconfig/firewall.local reload fi ;; restart) # run local firewall configuration, if present if [ -x /etc/sysconfig/firewall.local ]; then /etc/sysconfig/firewall.local stop fi $0 start ;; *) echo "Usage: $0 {start|reload|restart}" exit 1 ;; esac exit 0