]>
git.ipfire.org Git - 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 if [ -r "/var/ipfire/tor/settings" ]; then
29 eval $
(/usr
/local
/bin
/readhash
/var
/ipfire
/tor
/settings
)
31 IFACE
=`/bin/cat /var/ipfire/red/iface 2> /dev/null | /usr/bin/tr -d '\012'`
32 if [ -z $IFACE ]; then
36 if [ -f /var
/ipfire
/red
/device
]; then
37 DEVICE
=`/bin/cat /var/ipfire/red/device 2> /dev/null | /usr/bin/tr -d '\012'`
42 IPS_REPEAT_MARK
="0x80000000"
43 IPS_REPEAT_MASK
="0x80000000"
44 IPS_BYPASS_MARK
="0x40000000"
45 IPS_BYPASS_MASK
="0x40000000"
47 IPSET_DB_DIR
="/var/lib/location/ipset"
50 /sbin
/iptables
--wait "$@"
54 # Flush all rules and delete all custom chains
65 iptables
-P INPUT DROP
66 iptables
-P FORWARD DROP
67 iptables
-P OUTPUT ACCEPT
69 # Enable TRACE logging to syslog
71 sysctl
-q -w net.netfilter.nf_log
.2=nf_log_ipv4
73 # IPS Bypass Chain which stores the BYPASS bit in connection tracking
75 iptables
-A IPSBYPASS
-j CONNMARK
--save-mark --mask "$(( ~IPS_REPEAT_MASK & 0xffffffff ))"
77 # Jump into bypass chain when the BYPASS bit is set
78 for chain
in INPUT FORWARD OUTPUT
; do
79 iptables
-A "${chain}" -m mark \
80 --mark "$(( IPS_REPEAT_MARK | IPS_BYPASS_MARK ))/$(( IPS_REPEAT_MASK | IPS_BYPASS_MASK ))" -j IPSBYPASS
83 # Empty LOG_DROP and LOG_REJECT chains
85 iptables
-A LOG_DROP
-m limit
--limit 10/second
-j LOG
86 iptables
-A LOG_DROP
-j DROP
87 iptables
-N LOG_REJECT
88 iptables
-A LOG_REJECT
-m limit
--limit 10/second
-j LOG
89 iptables
-A LOG_REJECT
-j REJECT
91 # This chain will log, then DROPs packets with certain bad combinations
92 # of flags might indicate a port-scan attempt (xmas, null, etc.)
94 if [ "$DROPPORTSCAN" == "on" ]; then
95 iptables
-A PSCAN
-p tcp
-m limit
--limit 10/second
-j LOG
--log-prefix "DROP_TCP Scan " -m comment
--comment "DROP_TCP PScan"
96 iptables
-A PSCAN
-p udp
-m limit
--limit 10/second
-j LOG
--log-prefix "DROP_UDP Scan " -m comment
--comment "DROP_UDP PScan"
97 iptables
-A PSCAN
-p icmp
-m limit
--limit 10/second
-j LOG
--log-prefix "DROP_ICMP Scan " -m comment
--comment "DROP_ICMP PScan"
98 iptables
-A PSCAN
-f -m limit
--limit 10/second
-j LOG
--log-prefix "DROP_FRAG Scan " -m comment
--comment "DROP_FRAG PScan"
100 iptables
-A PSCAN
-j DROP
-m comment
--comment "DROP_PScan"
102 # New tcp packets without SYN set - could well be an obscure type of port scan
103 # that's not covered above, may just be a broken Windows machine
104 iptables
-N NEWNOTSYN
105 if [ "$DROPNEWNOTSYN" == "on" ]; then
106 iptables
-A NEWNOTSYN
-m limit
--limit 10/second
-j LOG
--log-prefix "DROP_NEWNOTSYN "
108 iptables
-A NEWNOTSYN
-j DROP
-m comment
--comment "DROP_NEWNOTSYN"
110 # Log and subsequently drop spoofed packets or "martians", arriving from sources
111 # on interfaces where we don't expect them
112 iptables
-N SPOOFED_MARTIAN
113 if [ "$DROPSPOOFEDMARTIAN" == "on" ]; then
114 iptables
-A SPOOFED_MARTIAN
-m limit
--limit 10/second
-j LOG
--log-prefix "DROP_SPOOFED_MARTIAN "
116 iptables
-A SPOOFED_MARTIAN
-j DROP
-m comment
--comment "DROP_SPOOFED_MARTIAN"
118 # Chain to contain all the rules relating to bad TCP flags
121 # Don't check loopback
122 iptables
-A BADTCP
-i lo
-j RETURN
124 # Disallow packets frequently used by port-scanners
125 # NMAP FIN/URG/PSH (XMAS scan)
126 iptables
-A BADTCP
-p tcp
--tcp-flags ALL FIN
,URG
,PSH
-j PSCAN
127 # SYN/RST/ACK/FIN/URG
128 iptables
-A BADTCP
-p tcp
--tcp-flags ALL SYN
,RST
,ACK
,FIN
,URG
-j PSCAN
130 iptables
-A BADTCP
-p tcp
--tcp-flags ALL ALL
-j PSCAN
132 iptables
-A BADTCP
-p tcp
--tcp-flags ALL FIN
-j PSCAN
133 # SYN/RST (also catches xmas variants that set SYN+RST+...)
134 iptables
-A BADTCP
-p tcp
--tcp-flags SYN
,RST SYN
,RST
-j PSCAN
135 # SYN/FIN (QueSO or nmap OS probe)
136 iptables
-A BADTCP
-p tcp
--tcp-flags SYN
,FIN SYN
,FIN
-j PSCAN
138 iptables
-A BADTCP
-p tcp
--tcp-flags ALL NONE
-j PSCAN
139 # NEW TCP without SYN
140 iptables
-A BADTCP
-p tcp
! --syn -m conntrack
--ctstate NEW
-j NEWNOTSYN
142 iptables
-A INPUT
-p tcp
-j BADTCP
143 iptables
-A FORWARD
-p tcp
-j BADTCP
145 # Connection tracking chains
146 iptables
-N CTINVALID
147 if [ "$LOGDROPCTINVALID" == "on" ]; then
148 iptables
-A CTINVALID
-m limit
--limit 10/second
-j LOG
--log-prefix "DROP_CTINVALID "
150 iptables
-A CTINVALID
-j DROP
-m comment
--comment "DROP_CTINVALID"
152 iptables
-N CONNTRACK
153 iptables
-A CONNTRACK
-m conntrack
--ctstate ESTABLISHED
-j ACCEPT
154 iptables
-A CONNTRACK
-m conntrack
--ctstate INVALID
-j CTINVALID
155 iptables
-A CONNTRACK
-p icmp
-m conntrack
--ctstate RELATED
-j ACCEPT
157 # Restore any connection marks
158 iptables
-t mangle
-A PREROUTING
-j CONNMARK
--restore-mark
160 # Fix for braindead ISPs
161 iptables
-A FORWARD
-p tcp
--tcp-flags SYN
,RST SYN
-j TCPMSS
--clamp-mss-to-pmtu
163 # CUSTOM chains, can be used by the users themselves
164 iptables
-N CUSTOMINPUT
165 iptables
-A INPUT
-j CUSTOMINPUT
166 iptables
-N CUSTOMFORWARD
167 iptables
-A FORWARD
-j CUSTOMFORWARD
168 iptables
-N CUSTOMOUTPUT
169 iptables
-A OUTPUT
-j CUSTOMOUTPUT
170 iptables
-t nat
-N CUSTOMPREROUTING
171 iptables
-t nat
-A PREROUTING
-j CUSTOMPREROUTING
172 iptables
-t nat
-N CUSTOMPOSTROUTING
173 iptables
-t nat
-A POSTROUTING
-j CUSTOMPOSTROUTING
175 # Chains for networks known as being hostile, posing a technical threat to our users
176 # (i. e. listed at Spamhaus DROP et al.)
178 iptables
-A INPUT
-j HOSTILE
179 iptables
-A FORWARD
-j HOSTILE
180 iptables
-A OUTPUT
-j HOSTILE
182 iptables
-N HOSTILE_DROP_IN
183 if [ "$LOGDROPHOSTILEIN" == "on" ]; then
184 iptables
-A HOSTILE_DROP_IN
-m limit
--limit 10/second
-j LOG
--log-prefix "DROP_HOSTILE "
186 iptables
-A HOSTILE_DROP_IN
-j DROP
-m comment
--comment "DROP_HOSTILE"
188 iptables
-N HOSTILE_DROP_OUT
189 if [ "$LOGDROPHOSTILEOUT" == "on" ]; then
190 iptables
-A HOSTILE_DROP_OUT
-m limit
--limit 10/second
-j LOG
--log-prefix "DROP_HOSTILE "
192 iptables
-A HOSTILE_DROP_OUT
-j DROP
-m comment
--comment "DROP_HOSTILE"
195 # IP Address Blocklist chains
196 iptables
-N BLOCKLISTIN
197 iptables
-N BLOCKLISTOUT
198 iptables
-A INPUT
! -p icmp
-j BLOCKLISTIN
199 iptables
-A FORWARD
! -p icmp
-j BLOCKLISTIN
200 iptables
-A FORWARD
! -p icmp
-j BLOCKLISTOUT
201 iptables
-A OUTPUT
! -p icmp
-j BLOCKLISTOUT
203 # IPS (Guardian) chains
205 iptables
-A INPUT
-j GUARDIAN
206 iptables
-A FORWARD
-j GUARDIAN
208 # Block non-established IPsec networks
209 iptables
-N IPSECBLOCK
210 iptables
-A FORWARD
-m policy
--dir out
--pol none
-j IPSECBLOCK
211 iptables
-A OUTPUT
-m policy
--dir out
--pol none
-j IPSECBLOCK
213 # Block OpenVPN transfer networks
214 iptables
-N OVPNBLOCK
215 iptables
-A INPUT
-i tun
+ -j OVPNBLOCK
216 iptables
-A FORWARD
-i tun
+ -j OVPNBLOCK
217 iptables
-A FORWARD
-o tun
+ -j OVPNBLOCK
219 # IPS (Suricata) chains
220 iptables
-N IPS_INPUT
221 iptables
-N IPS_FORWARD
222 iptables
-N IPS_OUTPUT
224 for chain
in INPUT FORWARD OUTPUT
; do
225 iptables
-A "${chain}" -m mark
--mark "0x0/$(( IPS_REPEAT_MASK | IPS_BYPASS_MASK ))" -j "IPS_${chain}"
228 # OpenVPN transfer network translation
229 iptables
-t nat
-N OVPNNAT
230 iptables
-t nat
-A POSTROUTING
-j OVPNNAT
232 # IPTV chains for IGMPPROXY
233 iptables
-N IPTVINPUT
234 iptables
-A INPUT
-j IPTVINPUT
235 iptables
-N IPTVFORWARD
236 iptables
-A FORWARD
-j IPTVFORWARD
238 # Allow to ping the firewall.
239 iptables
-N ICMPINPUT
240 iptables
-A INPUT
-j ICMPINPUT
241 iptables
-A ICMPINPUT
-p icmp
--icmp-type 8 -j ACCEPT
243 # Accept everything on loopback
245 iptables
-A LOOPBACK
-i lo
-j ACCEPT
246 iptables
-A LOOPBACK
-o lo
-j ACCEPT
248 # Filter all packets with loopback addresses on non-loopback interfaces (spoofed)
249 iptables
-A LOOPBACK
-s 127.0.0.0/8 -j SPOOFED_MARTIAN
250 iptables
-A LOOPBACK
-d 127.0.0.0/8 -j SPOOFED_MARTIAN
252 for i
in INPUT FORWARD OUTPUT
; do
253 iptables
-A ${i} -j LOOPBACK
257 iptables
-N CAPTIVE_PORTAL
258 iptables
-N CAPTIVE_PORTAL_CLIENTS
259 for i
in INPUT FORWARD
; do
260 iptables
-A ${i} -j CAPTIVE_PORTAL
263 # Accept everything connected
264 for i
in INPUT FORWARD OUTPUT
; do
265 iptables
-A ${i} -j CONNTRACK
269 iptables
-N DHCPINPUT
270 iptables
-A DHCPINPUT
-p udp
--sport 68 --dport 67 -j ACCEPT
271 iptables
-A DHCPINPUT
-p tcp
--sport 68 --dport 67 -j ACCEPT
273 iptables
-N DHCPOUTPUT
274 iptables
-A DHCPOUTPUT
-p udp
--sport 67 --dport 68 -j ACCEPT
275 iptables
-A DHCPOUTPUT
-p tcp
--sport 67 --dport 68 -j ACCEPT
277 # Allow DHCP on GREEN
278 iptables
-N DHCPGREENINPUT
279 iptables
-N DHCPGREENOUTPUT
280 if [ -n "${GREEN_DEV}" ]; then
281 iptables
-A INPUT
-i "${GREEN_DEV}" -j DHCPGREENINPUT
282 iptables
-A OUTPUT
-o "${GREEN_DEV}" -j DHCPGREENOUTPUT
285 # Allow DHCP on BLUE to be turned on/off
286 iptables
-N DHCPBLUEINPUT
287 iptables
-N DHCPBLUEOUTPUT
288 if [ -n "${BLUE_DEV}" ]; then
289 iptables
-A INPUT
-i "${BLUE_DEV}" -j DHCPBLUEINPUT
290 iptables
-A OUTPUT
-o "${BLUE_DEV}" -j DHCPBLUEOUTPUT
294 iptables
-N TOR_INPUT
295 iptables
-A INPUT
-j TOR_INPUT
298 iptables
-N LOCATIONBLOCK
299 iptables
-A INPUT
-j LOCATIONBLOCK
300 iptables
-A FORWARD
-j LOCATIONBLOCK
302 # trafic from ipsecX/TUN/TAP interfaces, before "-i GREEN_DEV" accept everything
303 iptables
-N IPSECINPUT
304 iptables
-N IPSECFORWARD
305 iptables
-N IPSECOUTPUT
306 iptables
-A INPUT
-j IPSECINPUT
307 iptables
-A FORWARD
-j IPSECFORWARD
308 iptables
-A OUTPUT
-j IPSECOUTPUT
309 iptables
-t nat
-N IPSECNAT
310 iptables
-t nat
-A POSTROUTING
-j IPSECNAT
312 # localhost and ethernet.
313 # Always allow accessing the web GUI from GREEN.
315 iptables
-A INPUT
-j GUIINPUT
316 if [ -n "${GREEN_DEV}" ]; then
317 iptables
-A GUIINPUT
-i "${GREEN_DEV}" -p tcp
--dport 444 -j ACCEPT
321 iptables
-N WIRELESSINPUT
322 iptables
-A INPUT
-m conntrack
--ctstate NEW
-j WIRELESSINPUT
323 iptables
-N WIRELESSFORWARD
324 iptables
-A FORWARD
-m conntrack
--ctstate NEW
-j WIRELESSFORWARD
327 iptables
-N OVPNINPUT
328 iptables
-A INPUT
-j OVPNINPUT
331 iptables
-N TOR_OUTPUT
332 iptables
-A OUTPUT
-j TOR_OUTPUT
334 # Jump into the actual firewall ruleset.
336 iptables
-A INPUT
-j INPUTFW
338 iptables
-N OUTGOINGFW
339 iptables
-A OUTPUT
-j OUTGOINGFW
341 iptables
-N FORWARDFW
342 iptables
-A FORWARD
-j FORWARDFW
345 iptables
-t nat
-N NAT_SOURCE
346 iptables
-t nat
-A POSTROUTING
-j NAT_SOURCE
349 iptables
-t nat
-N CAPTIVE_PORTAL
350 iptables
-t nat
-A PREROUTING
-j CAPTIVE_PORTAL
352 # Custom prerouting chains (for transparent proxy)
353 iptables
-t nat
-N SQUID
354 iptables
-t nat
-A PREROUTING
-j SQUID
357 iptables
-t nat
-N NAT_DESTINATION
358 iptables
-t nat
-A PREROUTING
-j NAT_DESTINATION
359 iptables
-t nat
-A OUTPUT
-j NAT_DESTINATION
361 iptables
-t mangle
-N NAT_DESTINATION
362 iptables
-t mangle
-A PREROUTING
-j NAT_DESTINATION
364 iptables
-t nat
-N NAT_DESTINATION_FIX
365 iptables
-t nat
-A POSTROUTING
-j NAT_DESTINATION_FIX
367 if [ -n "${GREEN_ADDRESS}" ]; then
368 iptables
-t nat
-A NAT_DESTINATION_FIX \
369 -m mark
--mark "0x01000000/${NAT_MASK}" -j SNAT
--to-source "${GREEN_ADDRESS}"
372 if [ -n "${BLUE_ADDRESS}" ]; then
373 iptables
-t nat
-A NAT_DESTINATION_FIX \
374 -m mark
--mark "0x02000000/${NAT_MASK}" -j SNAT
--to-source "${BLUE_ADDRESS}"
377 if [ -n "${ORANGE_ADDRESS}" ]; then
378 iptables
-t nat
-A NAT_DESTINATION_FIX \
379 -m mark
--mark "0x04000000/${NAT_MASK}" -j SNAT
--to-source "${ORANGE_ADDRESS}"
382 # RED chain, used for the red interface
384 iptables
-A INPUT
-j REDINPUT
385 iptables
-N REDFORWARD
386 iptables
-A FORWARD
-j REDFORWARD
387 iptables
-t nat
-N REDNAT
388 iptables
-t nat
-A POSTROUTING
-j REDNAT
390 # Populate IPsec chains
391 /usr
/lib
/firewall
/ipsec-policy
393 # Apply OpenVPN firewall rules
394 /usr
/local
/bin
/openvpnctrl
--firewall-rules
397 /usr
/local
/bin
/wirelessctrl
400 /usr
/local
/bin
/captivectrl
402 # If a Tor relay is enabled apply firewall rules
403 if [ "${TOR_RELAY_ENABLED}" = "on" -a -n "${TOR_RELAY_PORT}" ]; then
404 /usr
/local
/bin
/torctrl restart
1> /dev
/null
409 iptables
-A INPUT
-j POLICYIN
410 iptables
-N POLICYFWD
411 iptables
-A FORWARD
-j POLICYFWD
412 iptables
-N POLICYOUT
413 iptables
-A OUTPUT
-j POLICYOUT
415 # Initialize firewall policies.
416 /usr
/sbin
/firewall-policy
418 # Install firewall rules for the red interface.
421 # If red has not been brought up yet, we will
422 # add the blocking rules for MASQUERADE
423 if [ ! -e "/var/ipfire/red/active" ]; then
430 iptables
-F REDFORWARD
431 iptables
-t nat
-F REDNAT
433 # Prohibit spoofing our own IP address on RED
434 if [ -f /var
/ipfire
/red
/active
]; then
435 REDIP
="$( cat /var/ipfire/red/local-ipaddress )";
437 if [ "$IFACE" != "" ]; then
438 iptables
-A REDINPUT
-s $REDIP -i $IFACE -j SPOOFED_MARTIAN
439 elif [ "$DEVICE" != "" ]; then
440 iptables
-A REDINPUT
-s $REDIP -i $DEVICE -j SPOOFED_MARTIAN
445 if [ "$DEVICE" != "" -a "$TYPE" == "PPTP" -a "$METHOD" == "DHCP" ]; then
446 iptables
-A REDINPUT
-p tcp
--source-port 67 --destination-port 68 -i $DEVICE -j ACCEPT
447 iptables
-A REDINPUT
-p udp
--source-port 67 --destination-port 68 -i $DEVICE -j ACCEPT
450 if [ "$IFACE" != "" -a -f /var
/ipfire
/red
/active
]; then
452 if [ "$RED_DEV" != "" -a "$RED_TYPE" == "DHCP" ]; then
453 iptables
-A REDINPUT
-p tcp
--source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
454 iptables
-A REDINPUT
-p udp
--source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
456 if [ "$METHOD" == "DHCP" -a "$PROTOCOL" == "RFC1483" ]; then
457 iptables
-A REDINPUT
-p tcp
--source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
458 iptables
-A REDINPUT
-p udp
--source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
461 # Outgoing masquerading (don't masqerade IPsec)
462 iptables
-t nat
-A REDNAT
-m policy
--pol ipsec
--dir=out
-o "${IFACE}" -j RETURN
464 if [ "${IFACE}" = "${GREEN_DEV}" ]; then
465 iptables
-t nat
-A REDNAT
-i "${GREEN_DEV}" -o "${IFACE}" -j RETURN
468 local NO_MASQ_NETWORKS
470 if [ "${MASQUERADE_GREEN}" = "off" ]; then
471 NO_MASQ_NETWORKS
="${NO_MASQ_NETWORKS} ${GREEN_NETADDRESS}/${GREEN_NETMASK}"
474 if [ "${MASQUERADE_BLUE}" = "off" ]; then
475 NO_MASQ_NETWORKS
="${NO_MASQ_NETWORKS} ${BLUE_NETADDRESS}/${BLUE_NETMASK}"
478 if [ "${MASQUERADE_ORANGE}" = "off" ]; then
479 NO_MASQ_NETWORKS
="${NO_MASQ_NETWORKS} ${ORANGE_NETADDRESS}/${ORANGE_NETMASK}"
483 for network
in ${NO_MASQ_NETWORKS}; do
484 iptables
-t nat
-A REDNAT
-s "${network}" -o "${IFACE}" -j RETURN
487 # Masquerade everything else
488 iptables
-t nat
-A REDNAT
-o $IFACE -j MASQUERADE
492 /usr
/local
/bin
/firewallctrl
495 iptables_red_down
() {
496 # Prohibit packets to reach the masquerading rule
497 # while the WAN interface is down - this is required to
498 # circumvent udp related NAT issues
499 # http://forum.ipfire.org/index.php?topic=11127.0
500 if [ -n "${IFACE}" ]; then
501 iptables
-F REDFORWARD
502 iptables
-A REDFORWARD
-o "${IFACE}" -j DROP
506 /usr
/local
/bin
/firewallctrl
509 # See how we were called.
512 boot_mesg
"Setting up firewall"
517 boot_mesg
"Reloading firewall"
522 boot_mesg
"Disabling firewall access to RED"
530 echo "Usage: $0 {start|reload|restart}"