]>
git.ipfire.org Git - people/mfischer/ipfire-2.x.git/blob - src/initscripts/system/firewall
2 ###############################################################################
4 # IPFire.org - A linux based firewall #
5 # Copyright (C) 2007-2022 IPFire Team <info@ipfire.org> #
7 # This program is free software: you can redistribute it and/or modify #
8 # it under the terms of the GNU General Public License as published by #
9 # the Free Software Foundation, either version 3 of the License, or #
10 # (at your option) any later version. #
12 # This program is distributed in the hope that it will be useful, #
13 # but WITHOUT ANY WARRANTY; without even the implied warranty of #
14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the #
15 # GNU General Public License for more details. #
17 # You should have received a copy of the GNU General Public License #
18 # along with this program. If not, see <http://www.gnu.org/licenses/>. #
20 ###############################################################################
25 eval $
(/usr
/local
/bin
/readhash
/var
/ipfire
/ppp
/settings
)
26 eval $
(/usr
/local
/bin
/readhash
/var
/ipfire
/ethernet
/settings
)
27 eval $
(/usr
/local
/bin
/readhash
/var
/ipfire
/optionsfw
/settings
)
28 IFACE
=`/bin/cat /var/ipfire/red/iface 2> /dev/null | /usr/bin/tr -d '\012'`
29 if [ -z $IFACE ]; then
33 if [ -f /var
/ipfire
/red
/device
]; then
34 DEVICE
=`/bin/cat /var/ipfire/red/device 2> /dev/null | /usr/bin/tr -d '\012'`
39 IPS_REPEAT_MARK
="0x80000000"
40 IPS_REPEAT_MASK
="0x80000000"
41 IPS_BYPASS_MARK
="0x40000000"
42 IPS_BYPASS_MASK
="0x40000000"
44 IPSET_DB_DIR
="/var/lib/location/ipset"
47 /sbin
/iptables
--wait "$@"
51 # Flush all rules and delete all custom chains
62 iptables
-P INPUT DROP
63 iptables
-P FORWARD DROP
64 iptables
-P OUTPUT ACCEPT
66 # Enable TRACE logging to syslog
68 sysctl
-q -w net.netfilter.nf_log
.2=nf_log_ipv4
70 # IPS Bypass Chain which stores the BYPASS bit in connection tracking
72 iptables
-A IPSBYPASS
-j CONNMARK
--save-mark --mask "$(( ~IPS_REPEAT_MASK & 0xffffffff ))"
74 # Jump into bypass chain when the BYPASS bit is set
75 for chain
in INPUT FORWARD OUTPUT
; do
76 iptables
-A "${chain}" -m mark \
77 --mark "$(( IPS_REPEAT_MARK | IPS_BYPASS_MARK ))/$(( IPS_REPEAT_MASK | IPS_BYPASS_MASK ))" -j IPSBYPASS
80 # Empty LOG_DROP and LOG_REJECT chains
82 iptables
-A LOG_DROP
-m limit
--limit 10/second
-j LOG
83 iptables
-A LOG_DROP
-j DROP
84 iptables
-N LOG_REJECT
85 iptables
-A LOG_REJECT
-m limit
--limit 10/second
-j LOG
86 iptables
-A LOG_REJECT
-j REJECT
88 # This chain will log, then DROPs packets with certain bad combinations
89 # of flags might indicate a port-scan attempt (xmas, null, etc.)
91 if [ "$DROPPORTSCAN" == "on" ]; then
92 iptables
-A PSCAN
-p tcp
-m limit
--limit 10/second
-j LOG
--log-prefix "DROP_TCP Scan " -m comment
--comment "DROP_TCP PScan"
93 iptables
-A PSCAN
-p udp
-m limit
--limit 10/second
-j LOG
--log-prefix "DROP_UDP Scan " -m comment
--comment "DROP_UDP PScan"
94 iptables
-A PSCAN
-p icmp
-m limit
--limit 10/second
-j LOG
--log-prefix "DROP_ICMP Scan " -m comment
--comment "DROP_ICMP PScan"
95 iptables
-A PSCAN
-f -m limit
--limit 10/second
-j LOG
--log-prefix "DROP_FRAG Scan " -m comment
--comment "DROP_FRAG PScan"
97 iptables
-A PSCAN
-j DROP
-m comment
--comment "DROP_PScan"
99 # New tcp packets without SYN set - could well be an obscure type of port scan
100 # that's not covered above, may just be a broken Windows machine
101 iptables
-N NEWNOTSYN
102 if [ "$DROPNEWNOTSYN" == "on" ]; then
103 iptables
-A NEWNOTSYN
-m limit
--limit 10/second
-j LOG
--log-prefix "DROP_NEWNOTSYN "
105 iptables
-A NEWNOTSYN
-j DROP
-m comment
--comment "DROP_NEWNOTSYN"
107 # Log and subsequently drop spoofed packets or "martians", arriving from sources
108 # on interfaces where we don't expect them
109 iptables
-N SPOOFED_MARTIAN
110 if [ "$DROPSPOOFEDMARTIAN" == "on" ]; then
111 iptables
-A SPOOFED_MARTIAN
-m limit
--limit 10/second
-j LOG
--log-prefix "DROP_SPOOFED_MARTIAN "
113 iptables
-A SPOOFED_MARTIAN
-j DROP
-m comment
--comment "DROP_SPOOFED_MARTIAN"
115 # Chain to contain all the rules relating to bad TCP flags
118 # Don't check loopback
119 iptables
-A BADTCP
-i lo
-j RETURN
121 # Disallow packets frequently used by port-scanners
122 # NMAP FIN/URG/PSH (XMAS scan)
123 iptables
-A BADTCP
-p tcp
--tcp-flags ALL FIN
,URG
,PSH
-j PSCAN
124 # SYN/RST/ACK/FIN/URG
125 iptables
-A BADTCP
-p tcp
--tcp-flags ALL SYN
,RST
,ACK
,FIN
,URG
-j PSCAN
127 iptables
-A BADTCP
-p tcp
--tcp-flags ALL ALL
-j PSCAN
129 iptables
-A BADTCP
-p tcp
--tcp-flags ALL FIN
-j PSCAN
130 # SYN/RST (also catches xmas variants that set SYN+RST+...)
131 iptables
-A BADTCP
-p tcp
--tcp-flags SYN
,RST SYN
,RST
-j PSCAN
132 # SYN/FIN (QueSO or nmap OS probe)
133 iptables
-A BADTCP
-p tcp
--tcp-flags SYN
,FIN SYN
,FIN
-j PSCAN
135 iptables
-A BADTCP
-p tcp
--tcp-flags ALL NONE
-j PSCAN
136 # NEW TCP without SYN
137 iptables
-A BADTCP
-p tcp
! --syn -m conntrack
--ctstate NEW
-j NEWNOTSYN
139 iptables
-A INPUT
-p tcp
-j BADTCP
140 iptables
-A FORWARD
-p tcp
-j BADTCP
142 # Connection tracking chains
143 iptables
-N CTINVALID
144 if [ "$LOGDROPCTINVALID" == "on" ]; then
145 iptables
-A CTINVALID
-m limit
--limit 10/second
-j LOG
--log-prefix "DROP_CTINVALID "
147 iptables
-A CTINVALID
-j DROP
-m comment
--comment "DROP_CTINVALID"
149 iptables
-N CONNTRACK
150 iptables
-A CONNTRACK
-m conntrack
--ctstate ESTABLISHED
-j ACCEPT
151 iptables
-A CONNTRACK
-m conntrack
--ctstate INVALID
-j CTINVALID
152 iptables
-A CONNTRACK
-p icmp
-m conntrack
--ctstate RELATED
-j ACCEPT
154 # Restore any connection marks
155 iptables
-t mangle
-A PREROUTING
-j CONNMARK
--restore-mark
157 # Fix for braindead ISPs
158 iptables
-A FORWARD
-p tcp
--tcp-flags SYN
,RST SYN
-j TCPMSS
--clamp-mss-to-pmtu
160 # CUSTOM chains, can be used by the users themselves
161 iptables
-N CUSTOMINPUT
162 iptables
-A INPUT
-j CUSTOMINPUT
163 iptables
-N CUSTOMFORWARD
164 iptables
-A FORWARD
-j CUSTOMFORWARD
165 iptables
-N CUSTOMOUTPUT
166 iptables
-A OUTPUT
-j CUSTOMOUTPUT
167 iptables
-t nat
-N CUSTOMPREROUTING
168 iptables
-t nat
-A PREROUTING
-j CUSTOMPREROUTING
169 iptables
-t nat
-N CUSTOMPOSTROUTING
170 iptables
-t nat
-A POSTROUTING
-j CUSTOMPOSTROUTING
172 # Log and drop any traffic from and to networks known as being hostile, posing
173 # a technical threat to our users (i. e. listed at Spamhaus DROP et al.)
175 if [ "$DROPHOSTILE" == "on" ]; then
176 # Call ipset and load the list which contains the hostile networks.
177 ipset restore
< $IPSET_DB_DIR/CC_XD.ipset4
179 iptables
-A HOSTILE
-m limit
--limit 10/second
-j LOG
--log-prefix "DROP_HOSTILE "
180 iptables
-A INPUT
-i $IFACE -m set --match-set CC_XD src
-j HOSTILE
181 iptables
-A FORWARD
-i $IFACE -m set --match-set CC_XD src
-j HOSTILE
182 iptables
-A FORWARD
-o $IFACE -m set --match-set CC_XD dst
-j HOSTILE
183 iptables
-A OUTPUT
-o $IFACE -m set --match-set CC_XD src
-j HOSTILE
185 iptables
-A HOSTILE
-j DROP
-m comment
--comment "DROP_HOSTILE"
187 # IPS (Guardian) chains
189 iptables
-A INPUT
-j GUARDIAN
190 iptables
-A FORWARD
-j GUARDIAN
192 # Block non-established IPsec networks
193 iptables
-N IPSECBLOCK
194 iptables
-A FORWARD
-m policy
--dir out
--pol none
-j IPSECBLOCK
195 iptables
-A OUTPUT
-m policy
--dir out
--pol none
-j IPSECBLOCK
197 # Block OpenVPN transfer networks
198 iptables
-N OVPNBLOCK
199 iptables
-A INPUT
-i tun
+ -j OVPNBLOCK
200 iptables
-A FORWARD
-i tun
+ -j OVPNBLOCK
201 iptables
-A FORWARD
-o tun
+ -j OVPNBLOCK
203 # IPS (Suricata) chains
204 iptables
-N IPS_INPUT
205 iptables
-N IPS_FORWARD
206 iptables
-N IPS_OUTPUT
208 for chain
in INPUT FORWARD OUTPUT
; do
209 iptables
-A "${chain}" -m mark
--mark "0x0/$(( IPS_REPEAT_MASK | IPS_BYPASS_MASK ))" -j "IPS_${chain}"
212 # OpenVPN transfer network translation
213 iptables
-t nat
-N OVPNNAT
214 iptables
-t nat
-A POSTROUTING
-j OVPNNAT
216 # IPTV chains for IGMPPROXY
217 iptables
-N IPTVINPUT
218 iptables
-A INPUT
-j IPTVINPUT
219 iptables
-N IPTVFORWARD
220 iptables
-A FORWARD
-j IPTVFORWARD
222 # Allow to ping the firewall.
223 iptables
-N ICMPINPUT
224 iptables
-A INPUT
-j ICMPINPUT
225 iptables
-A ICMPINPUT
-p icmp
--icmp-type 8 -j ACCEPT
227 # Accept everything on loopback
229 iptables
-A LOOPBACK
-i lo
-j ACCEPT
230 iptables
-A LOOPBACK
-o lo
-j ACCEPT
232 # Filter all packets with loopback addresses on non-loopback interfaces (spoofed)
233 iptables
-A LOOPBACK
-s 127.0.0.0/8 -j SPOOFED_MARTIAN
234 iptables
-A LOOPBACK
-d 127.0.0.0/8 -j SPOOFED_MARTIAN
236 for i
in INPUT FORWARD OUTPUT
; do
237 iptables
-A ${i} -j LOOPBACK
241 iptables
-N CAPTIVE_PORTAL
242 iptables
-N CAPTIVE_PORTAL_CLIENTS
243 for i
in INPUT FORWARD
; do
244 iptables
-A ${i} -j CAPTIVE_PORTAL
247 # Accept everything connected
248 for i
in INPUT FORWARD OUTPUT
; do
249 iptables
-A ${i} -j CONNTRACK
253 iptables
-N DHCPINPUT
254 iptables
-A DHCPINPUT
-p udp
--sport 68 --dport 67 -j ACCEPT
255 iptables
-A DHCPINPUT
-p tcp
--sport 68 --dport 67 -j ACCEPT
257 iptables
-N DHCPOUTPUT
258 iptables
-A DHCPOUTPUT
-p udp
--sport 67 --dport 68 -j ACCEPT
259 iptables
-A DHCPOUTPUT
-p tcp
--sport 67 --dport 68 -j ACCEPT
261 # Allow DHCP on GREEN
262 iptables
-N DHCPGREENINPUT
263 iptables
-N DHCPGREENOUTPUT
264 if [ -n "${GREEN_DEV}" ]; then
265 iptables
-A INPUT
-i "${GREEN_DEV}" -j DHCPGREENINPUT
266 iptables
-A OUTPUT
-o "${GREEN_DEV}" -j DHCPGREENOUTPUT
269 # Allow DHCP on BLUE to be turned on/off
270 iptables
-N DHCPBLUEINPUT
271 iptables
-N DHCPBLUEOUTPUT
272 if [ -n "${BLUE_DEV}" ]; then
273 iptables
-A INPUT
-i "${BLUE_DEV}" -j DHCPBLUEINPUT
274 iptables
-A OUTPUT
-o "${BLUE_DEV}" -j DHCPBLUEOUTPUT
278 iptables
-N TOR_INPUT
279 iptables
-A INPUT
-j TOR_INPUT
282 iptables
-N LOCATIONBLOCK
283 iptables
-A INPUT
-j LOCATIONBLOCK
284 iptables
-A FORWARD
-j LOCATIONBLOCK
286 # trafic from ipsecX/TUN/TAP interfaces, before "-i GREEN_DEV" accept everything
287 iptables
-N IPSECINPUT
288 iptables
-N IPSECFORWARD
289 iptables
-N IPSECOUTPUT
290 iptables
-A INPUT
-j IPSECINPUT
291 iptables
-A FORWARD
-j IPSECFORWARD
292 iptables
-A OUTPUT
-j IPSECOUTPUT
293 iptables
-t nat
-N IPSECNAT
294 iptables
-t nat
-A POSTROUTING
-j IPSECNAT
296 # localhost and ethernet.
297 # Always allow accessing the web GUI from GREEN.
299 iptables
-A INPUT
-j GUIINPUT
300 if [ -n "${GREEN_DEV}" ]; then
301 iptables
-A GUIINPUT
-i "${GREEN_DEV}" -p tcp
--dport 444 -j ACCEPT
305 iptables
-N WIRELESSINPUT
306 iptables
-A INPUT
-m conntrack
--ctstate NEW
-j WIRELESSINPUT
307 iptables
-N WIRELESSFORWARD
308 iptables
-A FORWARD
-m conntrack
--ctstate NEW
-j WIRELESSFORWARD
311 iptables
-N OVPNINPUT
312 iptables
-A INPUT
-j OVPNINPUT
315 iptables
-N TOR_OUTPUT
316 iptables
-A OUTPUT
-j TOR_OUTPUT
318 # Jump into the actual firewall ruleset.
320 iptables
-A INPUT
-j INPUTFW
322 iptables
-N OUTGOINGFW
323 iptables
-A OUTPUT
-j OUTGOINGFW
325 iptables
-N FORWARDFW
326 iptables
-A FORWARD
-j FORWARDFW
329 iptables
-t nat
-N NAT_SOURCE
330 iptables
-t nat
-A POSTROUTING
-j NAT_SOURCE
333 iptables
-t nat
-N CAPTIVE_PORTAL
334 iptables
-t nat
-A PREROUTING
-j CAPTIVE_PORTAL
336 # Custom prerouting chains (for transparent proxy)
337 iptables
-t nat
-N SQUID
338 iptables
-t nat
-A PREROUTING
-j SQUID
341 iptables
-t nat
-N NAT_DESTINATION
342 iptables
-t nat
-A PREROUTING
-j NAT_DESTINATION
343 iptables
-t nat
-A OUTPUT
-j NAT_DESTINATION
345 iptables
-t mangle
-N NAT_DESTINATION
346 iptables
-t mangle
-A PREROUTING
-j NAT_DESTINATION
348 iptables
-t nat
-N NAT_DESTINATION_FIX
349 iptables
-t nat
-A POSTROUTING
-j NAT_DESTINATION_FIX
351 if [ -n "${GREEN_ADDRESS}" ]; then
352 iptables
-t nat
-A NAT_DESTINATION_FIX \
353 -m mark
--mark "0x01000000/${NAT_MASK}" -j SNAT
--to-source "${GREEN_ADDRESS}"
356 if [ -n "${BLUE_ADDRESS}" ]; then
357 iptables
-t nat
-A NAT_DESTINATION_FIX \
358 -m mark
--mark "0x02000000/${NAT_MASK}" -j SNAT
--to-source "${BLUE_ADDRESS}"
361 if [ -n "${ORANGE_ADDRESS}" ]; then
362 iptables
-t nat
-A NAT_DESTINATION_FIX \
363 -m mark
--mark "0x04000000/${NAT_MASK}" -j SNAT
--to-source "${ORANGE_ADDRESS}"
366 # RED chain, used for the red interface
368 iptables
-A INPUT
-j REDINPUT
369 iptables
-N REDFORWARD
370 iptables
-A FORWARD
-j REDFORWARD
371 iptables
-t nat
-N REDNAT
372 iptables
-t nat
-A POSTROUTING
-j REDNAT
374 # Populate IPsec chains
375 /usr
/lib
/firewall
/ipsec-policy
377 # Apply OpenVPN firewall rules
378 /usr
/local
/bin
/openvpnctrl
--firewall-rules
381 /usr
/local
/bin
/wirelessctrl
384 /usr
/local
/bin
/captivectrl
388 iptables
-A INPUT
-j POLICYIN
389 iptables
-N POLICYFWD
390 iptables
-A FORWARD
-j POLICYFWD
391 iptables
-N POLICYOUT
392 iptables
-A OUTPUT
-j POLICYOUT
394 # Initialize firewall policies.
395 /usr
/sbin
/firewall-policy
397 # Install firewall rules for the red interface.
400 # If red has not been brought up yet, we will
401 # add the blocking rules for MASQUERADE
402 if [ ! -e "/var/ipfire/red/active" ]; then
409 iptables
-F REDFORWARD
410 iptables
-t nat
-F REDNAT
412 # Prohibit spoofing our own IP address on RED
413 if [ -f /var
/ipfire
/red
/active
]; then
414 REDIP
="$( cat /var/ipfire/red/local-ipaddress )";
416 if [ "$IFACE" != "" ]; then
417 iptables
-A REDINPUT
-s $REDIP -i $IFACE -j SPOOFED_MARTIAN
418 elif [ "$DEVICE" != "" ]; then
419 iptables
-A REDINPUT
-s $REDIP -i $DEVICE -j SPOOFED_MARTIAN
423 # PPPoE / PPTP Device
424 if [ "$IFACE" != "" ]; then
426 if [ "$DEVICE" != "" ]; then
427 iptables
-A REDINPUT
-i $DEVICE -j ACCEPT
429 if [ "$RED_TYPE" == "PPTP" -o "$RED_TYPE" == "PPPOE" ]; then
430 if [ "$RED_DEV" != "" ]; then
431 iptables
-A REDINPUT
-i $RED_DEV -j ACCEPT
437 if [ "$DEVICE" != "" -a "$TYPE" == "PPTP" -a "$METHOD" == "DHCP" ]; then
438 iptables
-A REDINPUT
-p tcp
--source-port 67 --destination-port 68 -i $DEVICE -j ACCEPT
439 iptables
-A REDINPUT
-p udp
--source-port 67 --destination-port 68 -i $DEVICE -j ACCEPT
442 if [ "$IFACE" != "" -a -f /var
/ipfire
/red
/active
]; then
444 if [ "$RED_DEV" != "" -a "$RED_TYPE" == "DHCP" ]; then
445 iptables
-A REDINPUT
-p tcp
--source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
446 iptables
-A REDINPUT
-p udp
--source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
448 if [ "$METHOD" == "DHCP" -a "$PROTOCOL" == "RFC1483" ]; then
449 iptables
-A REDINPUT
-p tcp
--source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
450 iptables
-A REDINPUT
-p udp
--source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
453 # Outgoing masquerading (don't masqerade IPsec)
454 iptables
-t nat
-A REDNAT
-m policy
--pol ipsec
--dir=out
-o "${IFACE}" -j RETURN
456 if [ "${IFACE}" = "${GREEN_DEV}" ]; then
457 iptables
-t nat
-A REDNAT
-i "${GREEN_DEV}" -o "${IFACE}" -j RETURN
460 local NO_MASQ_NETWORKS
462 if [ "${MASQUERADE_GREEN}" = "off" ]; then
463 NO_MASQ_NETWORKS
="${NO_MASQ_NETWORKS} ${GREEN_NETADDRESS}/${GREEN_NETMASK}"
466 if [ "${MASQUERADE_BLUE}" = "off" ]; then
467 NO_MASQ_NETWORKS
="${NO_MASQ_NETWORKS} ${BLUE_NETADDRESS}/${BLUE_NETMASK}"
470 if [ "${MASQUERADE_ORANGE}" = "off" ]; then
471 NO_MASQ_NETWORKS
="${NO_MASQ_NETWORKS} ${ORANGE_NETADDRESS}/${ORANGE_NETMASK}"
475 for network
in ${NO_MASQ_NETWORKS}; do
476 iptables
-t nat
-A REDNAT
-s "${network}" -o "${IFACE}" -j RETURN
479 # Masquerade everything else
480 iptables
-t nat
-A REDNAT
-o $IFACE -j MASQUERADE
484 /usr
/local
/bin
/firewallctrl
487 iptables_red_down
() {
488 # Prohibit packets to reach the masquerading rule
489 # while the WAN interface is down - this is required to
490 # circumvent udp related NAT issues
491 # http://forum.ipfire.org/index.php?topic=11127.0
492 if [ -n "${IFACE}" ]; then
493 iptables
-F REDFORWARD
494 iptables
-A REDFORWARD
-o "${IFACE}" -j DROP
498 /usr
/local
/bin
/firewallctrl
501 # See how we were called.
504 boot_mesg
"Setting up firewall"
509 boot_mesg
"Reloading firewall"
514 boot_mesg
"Disabling firewall access to RED"
522 echo "Usage: $0 {start|reload|restart}"