Files
bpfire/src/initscripts/init.d/firewall
Michael Tremer d22294fa7e firewall: Fix outgoing OpenVPN N2N tunnel packets.
Don't throw away packets from the firewall that pass through
an OpenVPN N2N tunnel.
2014-04-12 16:17:20 +02:00

379 lines
11 KiB
Bash

#!/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
iptables -A INPUT -i tun+ -j OVPNBLOCK
iptables -A FORWARD -i tun+ -j OVPNBLOCK
iptables -A FORWARD -o tun+ -j OVPNBLOCK
# 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 $GREEN_DEV -m conntrack --ctstate NEW -j ACCEPT ! -p icmp
# allow DHCP on BLUE to be turned on/off
iptables -N DHCPBLUEINPUT
iptables -A INPUT -j DHCPBLUEINPUT
# WIRELESS chains
iptables -N WIRELESSINPUT
iptables -A INPUT -m conntrack --ctstate NEW -j WIRELESSINPUT
iptables -N WIRELESSFORWARD
iptables -A FORWARD -m conntrack --ctstate NEW -j WIRELESSFORWARD
# OpenVPN
iptables -N OVPNINPUT
iptables -A INPUT -j OVPNINPUT
# TOR
iptables -N TOR_INPUT
iptables -A INPUT -j TOR_INPUT
# Jump into the actual firewall ruleset.
iptables -N INPUTFW
iptables -A INPUT -j INPUTFW
iptables -N OUTGOINGFW
iptables -A OUTPUT -j OUTGOINGFW
iptables -N FORWARDFW
iptables -A FORWARD -j FORWARDFW
# SNAT rules
iptables -t nat -N NAT_SOURCE
iptables -t nat -A POSTROUTING -j NAT_SOURCE
# Custom prerouting chains (for transparent proxy)
iptables -t nat -N SQUID
iptables -t nat -A PREROUTING -j SQUID
# DNAT rules
iptables -t nat -N NAT_DESTINATION
iptables -t nat -A PREROUTING -j NAT_DESTINATION
iptables -t nat -A OUTPUT -j NAT_DESTINATION
iptables -t mangle -N NAT_DESTINATION
iptables -t mangle -A PREROUTING -j NAT_DESTINATION
iptables -t nat -N NAT_DESTINATION_FIX
iptables -t nat -A POSTROUTING -j NAT_DESTINATION_FIX
iptables -t nat -A NAT_DESTINATION_FIX \
-m mark --mark 1 -j SNAT --to-source "${GREEN_ADDRESS}"
if [ -n "${BLUE_ADDRESS}" ]; then
iptables -t nat -A NAT_DESTINATION_FIX \
-m mark --mark 2 -j SNAT --to-source "${BLUE_ADDRESS}"
fi
if [ -n "${ORANGE_ADDRESS}" ]; then
iptables -t nat -A NAT_DESTINATION_FIX \
-m mark --mark 3 -j SNAT --to-source "${ORANGE_ADDRESS}"
fi
# 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
# 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
# Filter logging of incoming broadcasts.
iptables -N BROADCAST_FILTER
iptables -A INPUT -j BROADCAST_FILTER
iptables -A BROADCAST_FILTER -i "${GREEN_DEV}" -d "${GREEN_BROADCAST}" -j DROP
if [ -n "${BLUE_DEV}" -a -n "${BLUE_BROADCAST}" ]; then
iptables -A BROADCAST_FILTER -i "${BLUE_DEV}" -d "${BLUE_BROADCAST}" -j DROP
fi
if [ -n "${ORANGE_DEV}" -a -n "${ORANGE_BROADCAST}" ]; then
iptables -A BROADCAST_FILTER -i "${ORANGE_DEV}" -d "${ORANGE_BROADCAST}" -j DROP
fi
# 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
# Initialize firewall policies.
/usr/sbin/firewall-policy
# Install firewall rules for the red interface.
iptables_red
}
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 $IFACE -j RETURN
if [ "$IFACE" != "$GREEN_DEV" ]; then
iptables -t nat -A REDNAT -o $IFACE -j MASQUERADE
fi
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