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firewall: Always initialise DROP_HOSTILE chain, even if it's unused
[people/pmueller/ipfire-2.x.git] / src / initscripts / system / firewall
1 #!/bin/sh
2
3 . /etc/sysconfig/rc
4 . ${rc_functions}
5
6 eval $(/usr/local/bin/readhash /var/ipfire/ppp/settings)
7 eval $(/usr/local/bin/readhash /var/ipfire/ethernet/settings)
8 eval $(/usr/local/bin/readhash /var/ipfire/optionsfw/settings)
9 IFACE=`/bin/cat /var/ipfire/red/iface 2> /dev/null | /usr/bin/tr -d '\012'`
10
11 if [ -f /var/ipfire/red/device ]; then
12 DEVICE=`/bin/cat /var/ipfire/red/device 2> /dev/null | /usr/bin/tr -d '\012'`
13 fi
14
15 NAT_MASK="0x0f000000"
16
17 IPS_REPEAT_MARK="0x80000000"
18 IPS_REPEAT_MASK="0x80000000"
19 IPS_BYPASS_MARK="0x40000000"
20 IPS_BYPASS_MASK="0x40000000"
21
22 function iptables() {
23 /sbin/iptables --wait "$@"
24 }
25
26 iptables_init() {
27 # Flush all rules and delete all custom chains
28 iptables -F
29 iptables -t nat -F
30 iptables -t mangle -F
31 iptables -t raw -F
32 iptables -X
33 iptables -t nat -X
34 iptables -t mangle -X
35 iptables -t raw -X
36
37 # Set up policies
38 iptables -P INPUT DROP
39 iptables -P FORWARD DROP
40 iptables -P OUTPUT ACCEPT
41
42 # Enable TRACE logging to syslog
43 modprobe nf_log_ipv4
44 sysctl -q -w net.netfilter.nf_log.2=nf_log_ipv4
45
46 # IPS Bypass Chain which stores the BYPASS bit in connection tracking
47 iptables -N IPSBYPASS
48 iptables -A IPSBYPASS -j CONNMARK --save-mark --mask "$(( ~IPS_REPEAT_MASK & 0xffffffff ))"
49
50 # Jump into bypass chain when the BYPASS bit is set
51 for chain in INPUT FORWARD OUTPUT; do
52 iptables -A "${chain}" -m mark \
53 --mark "$(( IPS_REPEAT_MARK | IPS_BYPASS_MARK ))/$(( IPS_REPEAT_MASK | IPS_BYPASS_MASK ))" -j IPSBYPASS
54 done
55
56 # Empty LOG_DROP and LOG_REJECT chains
57 iptables -N LOG_DROP
58 iptables -A LOG_DROP -m limit --limit 10/second -j LOG
59 iptables -A LOG_DROP -j DROP
60 iptables -N LOG_REJECT
61 iptables -A LOG_REJECT -m limit --limit 10/second -j LOG
62 iptables -A LOG_REJECT -j REJECT
63
64 # This chain will log, then DROPs packets with certain bad combinations
65 # of flags might indicate a port-scan attempt (xmas, null, etc.)
66 iptables -N PSCAN
67 if [ "$DROPPORTSCAN" == "on" ]; then
68 iptables -A PSCAN -p tcp -m limit --limit 10/second -j LOG --log-prefix "DROP_TCP Scan " -m comment --comment "DROP_TCP PScan"
69 iptables -A PSCAN -p udp -m limit --limit 10/second -j LOG --log-prefix "DROP_UDP Scan " -m comment --comment "DROP_UDP PScan"
70 iptables -A PSCAN -p icmp -m limit --limit 10/second -j LOG --log-prefix "DROP_ICMP Scan " -m comment --comment "DROP_ICMP PScan"
71 iptables -A PSCAN -f -m limit --limit 10/second -j LOG --log-prefix "DROP_FRAG Scan " -m comment --comment "DROP_FRAG PScan"
72 fi
73 iptables -A PSCAN -j DROP -m comment --comment "DROP_PScan"
74
75 # New tcp packets without SYN set - could well be an obscure type of port scan
76 # that's not covered above, may just be a broken Windows machine
77 iptables -N NEWNOTSYN
78 if [ "$DROPNEWNOTSYN" == "on" ]; then
79 iptables -A NEWNOTSYN -m limit --limit 10/second -j LOG --log-prefix "DROP_NEWNOTSYN "
80 fi
81 iptables -A NEWNOTSYN -j DROP -m comment --comment "DROP_NEWNOTSYN"
82
83 # Log and subsequently drop spoofed packets or "martians", arriving from sources
84 # on interfaces where we don't expect them
85 iptables -N SPOOFED_MARTIAN
86 if [ "$DROPSPOOFEDMARTIAN" == "on" ]; then
87 iptables -A SPOOFED_MARTIAN -m limit --limit 10/second -j LOG --log-prefix "DROP_SPOOFED_MARTIAN "
88 fi
89 iptables -A SPOOFED_MARTIAN -j DROP -m comment --comment "DROP_SPOOFED_MARTIAN"
90
91 # Chain to contain all the rules relating to bad TCP flags
92 iptables -N BADTCP
93
94 # Don't check loopback
95 iptables -A BADTCP -i lo -j RETURN
96
97 # Disallow packets frequently used by port-scanners
98 # NMAP FIN/URG/PSH (XMAS scan)
99 iptables -A BADTCP -p tcp --tcp-flags ALL FIN,URG,PSH -j PSCAN
100 # SYN/RST/ACK/FIN/URG
101 iptables -A BADTCP -p tcp --tcp-flags ALL SYN,RST,ACK,FIN,URG -j PSCAN
102 # ALL/ALL
103 iptables -A BADTCP -p tcp --tcp-flags ALL ALL -j PSCAN
104 # FIN Stealth
105 iptables -A BADTCP -p tcp --tcp-flags ALL FIN -j PSCAN
106 # SYN/RST (also catches xmas variants that set SYN+RST+...)
107 iptables -A BADTCP -p tcp --tcp-flags SYN,RST SYN,RST -j PSCAN
108 # SYN/FIN (QueSO or nmap OS probe)
109 iptables -A BADTCP -p tcp --tcp-flags SYN,FIN SYN,FIN -j PSCAN
110 # Null
111 iptables -A BADTCP -p tcp --tcp-flags ALL NONE -j PSCAN
112 # NEW TCP without SYN
113 iptables -A BADTCP -p tcp ! --syn -m conntrack --ctstate NEW -j NEWNOTSYN
114
115 iptables -A INPUT -p tcp -j BADTCP
116 iptables -A FORWARD -p tcp -j BADTCP
117
118 # Connection tracking chains
119 iptables -N CONNTRACK
120 iptables -A CONNTRACK -m conntrack --ctstate ESTABLISHED -j ACCEPT
121 iptables -A CONNTRACK -m conntrack --ctstate INVALID -j LOG_DROP
122 iptables -A CONNTRACK -p icmp -m conntrack --ctstate RELATED -j ACCEPT
123
124 # Restore any connection marks
125 iptables -t mangle -A PREROUTING -j CONNMARK --restore-mark
126
127 # Fix for braindead ISPs
128 iptables -A FORWARD -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu
129
130 # CUSTOM chains, can be used by the users themselves
131 iptables -N CUSTOMINPUT
132 iptables -A INPUT -j CUSTOMINPUT
133 iptables -N CUSTOMFORWARD
134 iptables -A FORWARD -j CUSTOMFORWARD
135 iptables -N CUSTOMOUTPUT
136 iptables -A OUTPUT -j CUSTOMOUTPUT
137 iptables -t nat -N CUSTOMPREROUTING
138 iptables -t nat -A PREROUTING -j CUSTOMPREROUTING
139 iptables -t nat -N CUSTOMPOSTROUTING
140 iptables -t nat -A POSTROUTING -j CUSTOMPOSTROUTING
141
142 # Log and drop any traffic from and to networks known as being hostile, posing
143 # a technical threat to our users (i. e. listed at Spamhaus DROP et al.)
144 iptables -N DROP_HOSTILE
145 if [ "$DROPHOSTILE" == "on" ]; then
146 iptables -A DROP_HOSTILE -m limit --limit 10/second -j LOG --log-prefix "DROP_HOSTILE "
147
148 iptables -A INPUT -i $IFACE -m geoip --src-cc XD -j DROP_HOSTILE
149 iptables -A FORWARD -i $IFACE -m geoip --src-cc XD -j DROP_HOSTILE
150 iptables -A FORWARD -o $IFACE -m geoip --dst-cc XD -j DROP_HOSTILE
151 iptables -A OUTPUT -o $IFACE -m geoip --src-cc XD -j DROP_HOSTILE
152
153 iptables -A DROP_HOSTILE -j DROP -m comment --comment "DROP_HOSTILE"
154 fi
155
156 # P2PBLOCK
157 iptables -N P2PBLOCK
158 iptables -A INPUT -j P2PBLOCK
159 iptables -A FORWARD -j P2PBLOCK
160 iptables -A OUTPUT -j P2PBLOCK
161
162 # IPS (Guardian) chains
163 iptables -N GUARDIAN
164 iptables -A INPUT -j GUARDIAN
165 iptables -A FORWARD -j GUARDIAN
166
167 # Block non-established IPsec networks
168 iptables -N IPSECBLOCK
169 iptables -A FORWARD -m policy --dir out --pol none -j IPSECBLOCK
170 iptables -A OUTPUT -m policy --dir out --pol none -j IPSECBLOCK
171
172 # Block OpenVPN transfer networks
173 iptables -N OVPNBLOCK
174 iptables -A INPUT -i tun+ -j OVPNBLOCK
175 iptables -A FORWARD -i tun+ -j OVPNBLOCK
176 iptables -A FORWARD -o tun+ -j OVPNBLOCK
177
178 # IPS (Suricata) chains
179 iptables -N IPS_INPUT
180 iptables -N IPS_FORWARD
181 iptables -N IPS_OUTPUT
182
183 for chain in INPUT FORWARD OUTPUT; do
184 iptables -A "${chain}" -m mark --mark "0x0/$(( IPS_REPEAT_MASK | IPS_BYPASS_MASK ))" -j "IPS_${chain}"
185 done
186
187 # OpenVPN transfer network translation
188 iptables -t nat -N OVPNNAT
189 iptables -t nat -A POSTROUTING -j OVPNNAT
190
191 # IPTV chains for IGMPPROXY
192 iptables -N IPTVINPUT
193 iptables -A INPUT -j IPTVINPUT
194 iptables -N IPTVFORWARD
195 iptables -A FORWARD -j IPTVFORWARD
196
197 # Allow to ping the firewall.
198 iptables -N ICMPINPUT
199 iptables -A INPUT -j ICMPINPUT
200 iptables -A ICMPINPUT -p icmp --icmp-type 8 -j ACCEPT
201
202 # Accept everything on loopback if source/destination is loopback space...
203 iptables -N LOOPBACK
204 iptables -A LOOPBACK -i lo -s 127.0.0.0/8 -j ACCEPT
205 iptables -A LOOPBACK -o lo -d 127.0.0.0/8 -j ACCEPT
206
207 # ... and drop everything else on the loopback interface, since no other traffic should appear there
208 iptables -A LOOPBACK -i lo -j SPOOFED_MARTIAN
209 iptables -A LOOPBACK -o lo -j SPOOFED_MARTIAN
210
211 # Filter all packets with loopback addresses on non-loopback interfaces (spoofed)
212 iptables -A LOOPBACK -s 127.0.0.0/8 -j SPOOFED_MARTIAN
213 iptables -A LOOPBACK -d 127.0.0.0/8 -j SPOOFED_MARTIAN
214
215 for i in INPUT FORWARD OUTPUT; do
216 iptables -A ${i} -j LOOPBACK
217 done
218
219 # Captive portal
220 iptables -N CAPTIVE_PORTAL
221 iptables -N CAPTIVE_PORTAL_CLIENTS
222 for i in INPUT FORWARD; do
223 iptables -A ${i} -j CAPTIVE_PORTAL
224 done
225
226 # Accept everything connected
227 for i in INPUT FORWARD OUTPUT; do
228 iptables -A ${i} -j CONNTRACK
229 done
230
231 # Allow DHCP
232 iptables -N DHCPINPUT
233 iptables -A DHCPINPUT -p udp --sport 68 --dport 67 -j ACCEPT
234 iptables -A DHCPINPUT -p tcp --sport 68 --dport 67 -j ACCEPT
235
236 iptables -N DHCPOUTPUT
237 iptables -A DHCPOUTPUT -p udp --sport 67 --dport 68 -j ACCEPT
238 iptables -A DHCPOUTPUT -p tcp --sport 67 --dport 68 -j ACCEPT
239
240 # Allow DHCP on GREEN
241 iptables -N DHCPGREENINPUT
242 iptables -N DHCPGREENOUTPUT
243 if [ -n "${GREEN_DEV}" ]; then
244 iptables -A INPUT -i "${GREEN_DEV}" -j DHCPGREENINPUT
245 iptables -A OUTPUT -o "${GREEN_DEV}" -j DHCPGREENOUTPUT
246 fi
247
248 # Allow DHCP on BLUE to be turned on/off
249 iptables -N DHCPBLUEINPUT
250 iptables -N DHCPBLUEOUTPUT
251 if [ -n "${BLUE_DEV}" ]; then
252 iptables -A INPUT -i "${BLUE_DEV}" -j DHCPBLUEINPUT
253 iptables -A OUTPUT -o "${BLUE_DEV}" -j DHCPBLUEOUTPUT
254 fi
255
256 # Tor (inbound)
257 iptables -N TOR_INPUT
258 iptables -A INPUT -j TOR_INPUT
259
260 # Location Block
261 iptables -N LOCATIONBLOCK
262 iptables -A INPUT -j LOCATIONBLOCK
263 iptables -A FORWARD -j LOCATIONBLOCK
264
265 # trafic from ipsecX/TUN/TAP interfaces, before "-i GREEN_DEV" accept everything
266 iptables -N IPSECINPUT
267 iptables -N IPSECFORWARD
268 iptables -N IPSECOUTPUT
269 iptables -A INPUT -j IPSECINPUT
270 iptables -A FORWARD -j IPSECFORWARD
271 iptables -A OUTPUT -j IPSECOUTPUT
272 iptables -t nat -N IPSECNAT
273 iptables -t nat -A POSTROUTING -j IPSECNAT
274
275 # localhost and ethernet.
276 # Always allow accessing the web GUI from GREEN.
277 iptables -N GUIINPUT
278 iptables -A INPUT -j GUIINPUT
279 if [ -n "${GREEN_DEV}" ]; then
280 iptables -A GUIINPUT -i "${GREEN_DEV}" -p tcp --dport 444 -j ACCEPT
281 fi
282
283 # WIRELESS chains
284 iptables -N WIRELESSINPUT
285 iptables -A INPUT -m conntrack --ctstate NEW -j WIRELESSINPUT
286 iptables -N WIRELESSFORWARD
287 iptables -A FORWARD -m conntrack --ctstate NEW -j WIRELESSFORWARD
288
289 # OpenVPN
290 iptables -N OVPNINPUT
291 iptables -A INPUT -j OVPNINPUT
292
293 # Tor (outbound)
294 iptables -N TOR_OUTPUT
295 iptables -A OUTPUT -j TOR_OUTPUT
296
297 # Jump into the actual firewall ruleset.
298 iptables -N INPUTFW
299 iptables -A INPUT -j INPUTFW
300
301 iptables -N OUTGOINGFW
302 iptables -A OUTPUT -j OUTGOINGFW
303
304 iptables -N FORWARDFW
305 iptables -A FORWARD -j FORWARDFW
306
307 # SNAT rules
308 iptables -t nat -N NAT_SOURCE
309 iptables -t nat -A POSTROUTING -j NAT_SOURCE
310
311 # Captive Portal
312 iptables -t nat -N CAPTIVE_PORTAL
313 iptables -t nat -A PREROUTING -j CAPTIVE_PORTAL
314
315 # Custom prerouting chains (for transparent proxy)
316 iptables -t nat -N SQUID
317 iptables -t nat -A PREROUTING -j SQUID
318
319 # DNAT rules
320 iptables -t nat -N NAT_DESTINATION
321 iptables -t nat -A PREROUTING -j NAT_DESTINATION
322 iptables -t nat -A OUTPUT -j NAT_DESTINATION
323
324 iptables -t mangle -N NAT_DESTINATION
325 iptables -t mangle -A PREROUTING -j NAT_DESTINATION
326
327 iptables -t nat -N NAT_DESTINATION_FIX
328 iptables -t nat -A POSTROUTING -j NAT_DESTINATION_FIX
329
330 if [ -n "${GREEN_ADDRESS}" ]; then
331 iptables -t nat -A NAT_DESTINATION_FIX \
332 -m mark --mark "0x01000000/${NAT_MASK}" -j SNAT --to-source "${GREEN_ADDRESS}"
333 fi
334
335 if [ -n "${BLUE_ADDRESS}" ]; then
336 iptables -t nat -A NAT_DESTINATION_FIX \
337 -m mark --mark "0x02000000/${NAT_MASK}" -j SNAT --to-source "${BLUE_ADDRESS}"
338 fi
339
340 if [ -n "${ORANGE_ADDRESS}" ]; then
341 iptables -t nat -A NAT_DESTINATION_FIX \
342 -m mark --mark "0x04000000/${NAT_MASK}" -j SNAT --to-source "${ORANGE_ADDRESS}"
343 fi
344
345 # RED chain, used for the red interface
346 iptables -N REDINPUT
347 iptables -A INPUT -j REDINPUT
348 iptables -N REDFORWARD
349 iptables -A FORWARD -j REDFORWARD
350 iptables -t nat -N REDNAT
351 iptables -t nat -A POSTROUTING -j REDNAT
352
353 # Populate IPsec chains
354 /usr/lib/firewall/ipsec-policy
355
356 # Apply OpenVPN firewall rules
357 /usr/local/bin/openvpnctrl --firewall-rules
358
359 # run wirelessctrl
360 /usr/local/bin/wirelessctrl
361
362 # run captivectrl
363 /usr/local/bin/captivectrl
364
365 # POLICY CHAIN
366 iptables -N POLICYIN
367 iptables -A INPUT -j POLICYIN
368 iptables -N POLICYFWD
369 iptables -A FORWARD -j POLICYFWD
370 iptables -N POLICYOUT
371 iptables -A OUTPUT -j POLICYOUT
372
373 # Initialize firewall policies.
374 /usr/sbin/firewall-policy
375
376 # Install firewall rules for the red interface.
377 iptables_red_up
378
379 # If red has not been brought up yet, we will
380 # add the blocking rules for MASQUERADE
381 if [ ! -e "/var/ipfire/red/active" ]; then
382 iptables_red_down
383 fi
384 }
385
386 iptables_red_up() {
387 iptables -F REDINPUT
388 iptables -F REDFORWARD
389 iptables -t nat -F REDNAT
390
391 # Prohibit spoofing our own IP address on RED
392 if [ -f /var/ipfire/red/active ]; then
393 REDIP="$( cat /var/ipfire/red/local-ipaddress )";
394
395 if [ "$IFACE" != "" ]; then
396 iptables -A REDINPUT -s $REDIP -i $IFACE -j SPOOFED_MARTIAN
397 elif [ "$DEVICE" != "" ]; then
398 iptables -A REDINPUT -s $REDIP -i $DEVICE -j SPOOFED_MARTIAN
399 fi
400 fi
401
402 # PPPoE / PPTP Device
403 if [ "$IFACE" != "" ]; then
404 # PPPoE / PPTP
405 if [ "$DEVICE" != "" ]; then
406 iptables -A REDINPUT -i $DEVICE -j ACCEPT
407 fi
408 if [ "$RED_TYPE" == "PPTP" -o "$RED_TYPE" == "PPPOE" ]; then
409 if [ "$RED_DEV" != "" ]; then
410 iptables -A REDINPUT -i $RED_DEV -j ACCEPT
411 fi
412 fi
413 fi
414
415 # PPTP over DHCP
416 if [ "$DEVICE" != "" -a "$TYPE" == "PPTP" -a "$METHOD" == "DHCP" ]; then
417 iptables -A REDINPUT -p tcp --source-port 67 --destination-port 68 -i $DEVICE -j ACCEPT
418 iptables -A REDINPUT -p udp --source-port 67 --destination-port 68 -i $DEVICE -j ACCEPT
419 fi
420
421 if [ "$IFACE" != "" -a -f /var/ipfire/red/active ]; then
422 # DHCP
423 if [ "$RED_DEV" != "" -a "$RED_TYPE" == "DHCP" ]; then
424 iptables -A REDINPUT -p tcp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
425 iptables -A REDINPUT -p udp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
426 fi
427 if [ "$METHOD" == "DHCP" -a "$PROTOCOL" == "RFC1483" ]; then
428 iptables -A REDINPUT -p tcp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
429 iptables -A REDINPUT -p udp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
430 fi
431
432 # Outgoing masquerading (don't masqerade IPsec)
433 iptables -t nat -A REDNAT -m policy --pol ipsec --dir=out -o "${IFACE}" -j RETURN
434
435 if [ "${IFACE}" = "${GREEN_DEV}" ]; then
436 iptables -t nat -A REDNAT -i "${GREEN_DEV}" -o "${IFACE}" -j RETURN
437 fi
438
439 local NO_MASQ_NETWORKS
440
441 if [ "${MASQUERADE_GREEN}" = "off" ]; then
442 NO_MASQ_NETWORKS="${NO_MASQ_NETWORKS} ${GREEN_NETADDRESS}/${GREEN_NETMASK}"
443 fi
444
445 if [ "${MASQUERADE_BLUE}" = "off" ]; then
446 NO_MASQ_NETWORKS="${NO_MASQ_NETWORKS} ${BLUE_NETADDRESS}/${BLUE_NETMASK}"
447 fi
448
449 if [ "${MASQUERADE_ORANGE}" = "off" ]; then
450 NO_MASQ_NETWORKS="${NO_MASQ_NETWORKS} ${ORANGE_NETADDRESS}/${ORANGE_NETMASK}"
451 fi
452
453 local network
454 for network in ${NO_MASQ_NETWORKS}; do
455 iptables -t nat -A REDNAT -s "${network}" -o "${IFACE}" -j RETURN
456 done
457
458 # Masquerade everything else
459 iptables -t nat -A REDNAT -o $IFACE -j MASQUERADE
460 fi
461
462 # Reload all rules.
463 /usr/local/bin/firewallctrl
464 }
465
466 iptables_red_down() {
467 # Prohibit packets to reach the masquerading rule
468 # while the WAN interface is down - this is required to
469 # circumvent udp related NAT issues
470 # http://forum.ipfire.org/index.php?topic=11127.0
471 if [ -n "${IFACE}" ]; then
472 iptables -F REDFORWARD
473 iptables -A REDFORWARD -o "${IFACE}" -j DROP
474 fi
475
476 # Reload all rules.
477 /usr/local/bin/firewallctrl
478 }
479
480 # See how we were called.
481 case "$1" in
482 start)
483 boot_mesg "Setting up firewall"
484 iptables_init
485 evaluate_retval
486 ;;
487 reload|up)
488 boot_mesg "Reloading firewall"
489 iptables_red_up
490 evaluate_retval
491 ;;
492 down)
493 boot_mesg "Disabling firewall access to RED"
494 iptables_red_down
495 evaluate_retval
496 ;;
497 restart)
498 $0 start
499 ;;
500 *)
501 echo "Usage: $0 {start|reload|restart}"
502 exit 1
503 ;;
504 esac
505
506 exit 0