1 menu "Core Netfilter Configuration"
2 depends on NET && INET && NETFILTER
4 config NETFILTER_NETLINK
7 config NETFILTER_NETLINK_ACCT
8 tristate "Netfilter NFACCT over NFNETLINK interface"
9 depends on NETFILTER_ADVANCED
10 select NETFILTER_NETLINK
12 If this option is enabled, the kernel will include support
13 for extended accounting via NFNETLINK.
15 config NETFILTER_NETLINK_QUEUE
16 tristate "Netfilter NFQUEUE over NFNETLINK interface"
17 depends on NETFILTER_ADVANCED
18 select NETFILTER_NETLINK
20 If this option is enabled, the kernel will include support
21 for queueing packets via NFNETLINK.
23 config NETFILTER_NETLINK_LOG
24 tristate "Netfilter LOG over NFNETLINK interface"
25 default m if NETFILTER_ADVANCED=n
26 select NETFILTER_NETLINK
28 If this option is enabled, the kernel will include support
29 for logging packets via NFNETLINK.
31 This obsoletes the existing ipt_ULOG and ebg_ulog mechanisms,
32 and is also scheduled to replace the old syslog-based ipt_LOG
36 tristate "Netfilter connection tracking support"
37 default m if NETFILTER_ADVANCED=n
39 Connection tracking keeps a record of what packets have passed
40 through your machine, in order to figure out how they are related
43 This is required to do Masquerading or other kinds of Network
44 Address Translation. It can also be used to enhance packet
45 filtering (see `Connection state match support' below).
47 To compile it as a module, choose M here. If unsure, say N.
51 config NF_CONNTRACK_MARK
52 bool 'Connection mark tracking support'
53 depends on NETFILTER_ADVANCED
55 This option enables support for connection marks, used by the
56 `CONNMARK' target and `connmark' match. Similar to the mark value
57 of packets, but this mark value is kept in the conntrack session
58 instead of the individual packets.
60 config NF_CONNTRACK_SECMARK
61 bool 'Connection tracking security mark support'
62 depends on NETWORK_SECMARK
63 default m if NETFILTER_ADVANCED=n
65 This option enables security markings to be applied to
66 connections. Typically they are copied to connections from
67 packets using the CONNSECMARK target and copied back from
68 connections to packets with the same target, with the packets
69 being originally labeled via SECMARK.
73 config NF_CONNTRACK_ZONES
74 bool 'Connection tracking zones'
75 depends on NETFILTER_ADVANCED
76 depends on NETFILTER_XT_TARGET_CT
78 This option enables support for connection tracking zones.
79 Normally, each connection needs to have a unique system wide
80 identity. Connection tracking zones allow to have multiple
81 connections using the same identity, as long as they are
82 contained in different zones.
86 config NF_CONNTRACK_PROCFS
87 bool "Supply CT list in procfs (OBSOLETE)"
91 This option enables for the list of known conntrack entries
92 to be shown in procfs under net/netfilter/nf_conntrack. This
93 is considered obsolete in favor of using the conntrack(8)
94 tool which uses Netlink.
96 config NF_CONNTRACK_EVENTS
97 bool "Connection tracking events"
98 depends on NETFILTER_ADVANCED
100 If this option is enabled, the connection tracking code will
101 provide a notifier chain that can be used by other kernel code
102 to get notified about changes in the connection tracking state.
106 config NF_CONNTRACK_TIMEOUT
107 bool 'Connection tracking timeout'
108 depends on NETFILTER_ADVANCED
110 This option enables support for connection tracking timeout
111 extension. This allows you to attach timeout policies to flow
116 config NF_CONNTRACK_TIMESTAMP
117 bool 'Connection tracking timestamping'
118 depends on NETFILTER_ADVANCED
120 This option enables support for connection tracking timestamping.
121 This allows you to store the flow start-time and to obtain
122 the flow-stop time (once it has been destroyed) via Connection
127 config NF_CT_PROTO_DCCP
128 tristate 'DCCP protocol connection tracking support (EXPERIMENTAL)'
129 depends on EXPERIMENTAL
130 depends on NETFILTER_ADVANCED
133 With this option enabled, the layer 3 independent connection
134 tracking code will be able to do state tracking on DCCP connections.
138 config NF_CT_PROTO_GRE
141 config NF_CT_PROTO_SCTP
142 tristate 'SCTP protocol connection tracking support (EXPERIMENTAL)'
143 depends on EXPERIMENTAL
144 depends on NETFILTER_ADVANCED
147 With this option enabled, the layer 3 independent connection
148 tracking code will be able to do state tracking on SCTP connections.
150 If you want to compile it as a module, say M here and read
151 <file:Documentation/kbuild/modules.txt>. If unsure, say `N'.
153 config NF_CT_PROTO_UDPLITE
154 tristate 'UDP-Lite protocol connection tracking support'
155 depends on NETFILTER_ADVANCED
157 With this option enabled, the layer 3 independent connection
158 tracking code will be able to do state tracking on UDP-Lite
161 To compile it as a module, choose M here. If unsure, say N.
163 config NF_CONNTRACK_AMANDA
164 tristate "Amanda backup protocol support"
165 depends on NETFILTER_ADVANCED
167 select TEXTSEARCH_KMP
169 If you are running the Amanda backup package <http://www.amanda.org/>
170 on this machine or machines that will be MASQUERADED through this
171 machine, then you may want to enable this feature. This allows the
172 connection tracking and natting code to allow the sub-channels that
173 Amanda requires for communication of the backup data, messages and
176 To compile it as a module, choose M here. If unsure, say N.
178 config NF_CONNTRACK_FTP
179 tristate "FTP protocol support"
180 default m if NETFILTER_ADVANCED=n
182 Tracking FTP connections is problematic: special helpers are
183 required for tracking them, and doing masquerading and other forms
184 of Network Address Translation on them.
186 This is FTP support on Layer 3 independent connection tracking.
187 Layer 3 independent connection tracking is experimental scheme
188 which generalize ip_conntrack to support other layer 3 protocols.
190 To compile it as a module, choose M here. If unsure, say N.
192 config NF_CONNTRACK_H323
193 tristate "H.323 protocol support"
194 depends on (IPV6 || IPV6=n)
195 depends on NETFILTER_ADVANCED
197 H.323 is a VoIP signalling protocol from ITU-T. As one of the most
198 important VoIP protocols, it is widely used by voice hardware and
199 software including voice gateways, IP phones, Netmeeting, OpenPhone,
202 With this module you can support H.323 on a connection tracking/NAT
205 This module supports RAS, Fast Start, H.245 Tunnelling, Call
206 Forwarding, RTP/RTCP and T.120 based audio, video, fax, chat,
207 whiteboard, file transfer, etc. For more information, please
208 visit http://nath323.sourceforge.net/.
210 To compile it as a module, choose M here. If unsure, say N.
212 config NF_CONNTRACK_IRC
213 tristate "IRC protocol support"
214 default m if NETFILTER_ADVANCED=n
216 There is a commonly-used extension to IRC called
217 Direct Client-to-Client Protocol (DCC). This enables users to send
218 files to each other, and also chat to each other without the need
219 of a server. DCC Sending is used anywhere you send files over IRC,
220 and DCC Chat is most commonly used by Eggdrop bots. If you are
221 using NAT, this extension will enable you to send files and initiate
222 chats. Note that you do NOT need this extension to get files or
223 have others initiate chats, or everything else in IRC.
225 To compile it as a module, choose M here. If unsure, say N.
227 config NF_CONNTRACK_BROADCAST
230 config NF_CONNTRACK_NETBIOS_NS
231 tristate "NetBIOS name service protocol support"
232 select NF_CONNTRACK_BROADCAST
234 NetBIOS name service requests are sent as broadcast messages from an
235 unprivileged port and responded to with unicast messages to the
236 same port. This make them hard to firewall properly because connection
237 tracking doesn't deal with broadcasts. This helper tracks locally
238 originating NetBIOS name service requests and the corresponding
239 responses. It relies on correct IP address configuration, specifically
240 netmask and broadcast address. When properly configured, the output
241 of "ip address show" should look similar to this:
243 $ ip -4 address show eth0
244 4: eth0: <BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 1000
245 inet 172.16.2.252/24 brd 172.16.2.255 scope global eth0
247 To compile it as a module, choose M here. If unsure, say N.
249 config NF_CONNTRACK_SNMP
250 tristate "SNMP service protocol support"
251 depends on NETFILTER_ADVANCED
252 select NF_CONNTRACK_BROADCAST
254 SNMP service requests are sent as broadcast messages from an
255 unprivileged port and responded to with unicast messages to the
256 same port. This make them hard to firewall properly because connection
257 tracking doesn't deal with broadcasts. This helper tracks locally
258 originating SNMP service requests and the corresponding
259 responses. It relies on correct IP address configuration, specifically
260 netmask and broadcast address.
262 To compile it as a module, choose M here. If unsure, say N.
264 config NF_CONNTRACK_PPTP
265 tristate "PPtP protocol support"
266 depends on NETFILTER_ADVANCED
267 select NF_CT_PROTO_GRE
269 This module adds support for PPTP (Point to Point Tunnelling
270 Protocol, RFC2637) connection tracking and NAT.
272 If you are running PPTP sessions over a stateful firewall or NAT
273 box, you may want to enable this feature.
275 Please note that not all PPTP modes of operation are supported yet.
276 Specifically these limitations exist:
277 - Blindly assumes that control connections are always established
278 in PNS->PAC direction. This is a violation of RFC2637.
279 - Only supports a single call within each session
281 To compile it as a module, choose M here. If unsure, say N.
283 config NF_CONNTRACK_SANE
284 tristate "SANE protocol support (EXPERIMENTAL)"
285 depends on EXPERIMENTAL
286 depends on NETFILTER_ADVANCED
288 SANE is a protocol for remote access to scanners as implemented
289 by the 'saned' daemon. Like FTP, it uses separate control and
292 With this module you can support SANE on a connection tracking
295 To compile it as a module, choose M here. If unsure, say N.
297 config NF_CONNTRACK_SIP
298 tristate "SIP protocol support"
299 default m if NETFILTER_ADVANCED=n
301 SIP is an application-layer control protocol that can establish,
302 modify, and terminate multimedia sessions (conferences) such as
303 Internet telephony calls. With the ip_conntrack_sip and
304 the nf_nat_sip modules you can support the protocol on a connection
305 tracking/NATing firewall.
307 To compile it as a module, choose M here. If unsure, say N.
309 config NF_CONNTRACK_TFTP
310 tristate "TFTP protocol support"
311 depends on NETFILTER_ADVANCED
313 TFTP connection tracking helper, this is required depending
314 on how restrictive your ruleset is.
315 If you are using a tftp client behind -j SNAT or -j MASQUERADING
318 To compile it as a module, choose M here. If unsure, say N.
321 tristate 'Connection tracking netlink interface'
322 select NETFILTER_NETLINK
323 default m if NETFILTER_ADVANCED=n
325 This option enables support for a netlink-based userspace interface
327 config NF_CT_NETLINK_TIMEOUT
328 tristate 'Connection tracking timeout tuning via Netlink'
329 select NETFILTER_NETLINK
330 depends on NETFILTER_ADVANCED
332 This option enables support for connection tracking timeout
333 fine-grain tuning. This allows you to attach specific timeout
334 policies to flows, instead of using the global timeout policy.
338 config NF_CT_NETLINK_HELPER
339 tristate 'Connection tracking helpers in user-space via Netlink'
340 select NETFILTER_NETLINK
341 depends on NF_CT_NETLINK
342 depends on NETFILTER_NETLINK_QUEUE
343 depends on NETFILTER_NETLINK_QUEUE_CT
344 depends on NETFILTER_ADVANCED
346 This option enables the user-space connection tracking helpers
351 config NETFILTER_NETLINK_QUEUE_CT
352 bool "NFQUEUE integration with Connection Tracking"
354 depends on NETFILTER_NETLINK_QUEUE
356 If this option is enabled, NFQUEUE can include Connection Tracking
357 information together with the packet is the enqueued via NFNETLINK.
361 # transparent proxy support
362 config NETFILTER_TPROXY
363 tristate "Transparent proxying support (EXPERIMENTAL)"
364 depends on EXPERIMENTAL
365 depends on IP_NF_MANGLE
366 depends on NETFILTER_ADVANCED
368 This option enables transparent proxying support, that is,
369 support for handling non-locally bound IPv4 TCP and UDP sockets.
370 For it to work you will have to configure certain iptables rules
371 and use policy routing. For more information on how to set it up
372 see Documentation/networking/tproxy.txt.
374 To compile it as a module, choose M here. If unsure, say N.
376 config NETFILTER_XTABLES
377 tristate "Netfilter Xtables support (required for ip_tables)"
378 default m if NETFILTER_ADVANCED=n
380 This is required if you intend to use any of ip_tables,
381 ip6_tables or arp_tables.
385 comment "Xtables combined modules"
387 config NETFILTER_XT_MARK
388 tristate 'nfmark target and match support'
389 default m if NETFILTER_ADVANCED=n
391 This option adds the "MARK" target and "mark" match.
393 Netfilter mark matching allows you to match packets based on the
394 "nfmark" value in the packet.
395 The target allows you to create rules in the "mangle" table which alter
396 the netfilter mark (nfmark) field associated with the packet.
398 Prior to routing, the nfmark can influence the routing method (see
399 "Use netfilter MARK value as routing key") and can also be used by
400 other subsystems to change their behavior.
402 config NETFILTER_XT_CONNMARK
403 tristate 'ctmark target and match support'
404 depends on NF_CONNTRACK
405 depends on NETFILTER_ADVANCED
406 select NF_CONNTRACK_MARK
408 This option adds the "CONNMARK" target and "connmark" match.
410 Netfilter allows you to store a mark value per connection (a.k.a.
411 ctmark), similarly to the packet mark (nfmark). Using this
412 target and match, you can set and match on this mark.
414 config NETFILTER_XT_SET
415 tristate 'set target and match support'
417 depends on NETFILTER_ADVANCED
419 This option adds the "SET" target and "set" match.
421 Using this target and match, you can add/delete and match
422 elements in the sets created by ipset(8).
424 To compile it as a module, choose M here. If unsure, say N.
426 # alphabetically ordered list of targets
428 comment "Xtables targets"
430 config NETFILTER_XT_TARGET_AUDIT
431 tristate "AUDIT target support"
433 depends on NETFILTER_ADVANCED
435 This option adds a 'AUDIT' target, which can be used to create
436 audit records for packets dropped/accepted.
438 To compileit as a module, choose M here. If unsure, say N.
440 config NETFILTER_XT_TARGET_CHECKSUM
441 tristate "CHECKSUM target support"
442 depends on IP_NF_MANGLE || IP6_NF_MANGLE
443 depends on NETFILTER_ADVANCED
445 This option adds a `CHECKSUM' target, which can be used in the iptables mangle
448 You can use this target to compute and fill in the checksum in
449 a packet that lacks a checksum. This is particularly useful,
450 if you need to work around old applications such as dhcp clients,
451 that do not work well with checksum offloads, but don't want to disable
452 checksum offload in your device.
454 To compile it as a module, choose M here. If unsure, say N.
456 config NETFILTER_XT_TARGET_CLASSIFY
457 tristate '"CLASSIFY" target support'
458 depends on NETFILTER_ADVANCED
460 This option adds a `CLASSIFY' target, which enables the user to set
461 the priority of a packet. Some qdiscs can use this value for
462 classification, among these are:
464 atm, cbq, dsmark, pfifo_fast, htb, prio
466 To compile it as a module, choose M here. If unsure, say N.
468 config NETFILTER_XT_TARGET_CONNMARK
469 tristate '"CONNMARK" target support'
470 depends on NF_CONNTRACK
471 depends on NETFILTER_ADVANCED
472 select NETFILTER_XT_CONNMARK
474 This is a backwards-compat option for the user's convenience
475 (e.g. when running oldconfig). It selects
476 CONFIG_NETFILTER_XT_CONNMARK (combined connmark/CONNMARK module).
478 config NETFILTER_XT_TARGET_CONNSECMARK
479 tristate '"CONNSECMARK" target support'
480 depends on NF_CONNTRACK && NF_CONNTRACK_SECMARK
481 default m if NETFILTER_ADVANCED=n
483 The CONNSECMARK target copies security markings from packets
484 to connections, and restores security markings from connections
485 to packets (if the packets are not already marked). This would
486 normally be used in conjunction with the SECMARK target.
488 To compile it as a module, choose M here. If unsure, say N.
490 config NETFILTER_XT_TARGET_CT
491 tristate '"CT" target support'
492 depends on NF_CONNTRACK
493 depends on IP_NF_RAW || IP6_NF_RAW
494 depends on NETFILTER_ADVANCED
496 This options adds a `CT' target, which allows to specify initial
497 connection tracking parameters like events to be delivered and
498 the helper to be used.
500 To compile it as a module, choose M here. If unsure, say N.
502 config NETFILTER_XT_TARGET_DSCP
503 tristate '"DSCP" and "TOS" target support'
504 depends on IP_NF_MANGLE || IP6_NF_MANGLE
505 depends on NETFILTER_ADVANCED
507 This option adds a `DSCP' target, which allows you to manipulate
508 the IPv4/IPv6 header DSCP field (differentiated services codepoint).
510 The DSCP field can have any value between 0x0 and 0x3f inclusive.
512 It also adds the "TOS" target, which allows you to create rules in
513 the "mangle" table which alter the Type Of Service field of an IPv4
514 or the Priority field of an IPv6 packet, prior to routing.
516 To compile it as a module, choose M here. If unsure, say N.
518 config NETFILTER_XT_TARGET_HL
519 tristate '"HL" hoplimit target support'
520 depends on IP_NF_MANGLE || IP6_NF_MANGLE
521 depends on NETFILTER_ADVANCED
523 This option adds the "HL" (for IPv6) and "TTL" (for IPv4)
524 targets, which enable the user to change the
525 hoplimit/time-to-live value of the IP header.
527 While it is safe to decrement the hoplimit/TTL value, the
528 modules also allow to increment and set the hoplimit value of
529 the header to arbitrary values. This is EXTREMELY DANGEROUS
530 since you can easily create immortal packets that loop
531 forever on the network.
533 config NETFILTER_XT_TARGET_HMARK
534 tristate '"HMARK" target support'
535 depends on (IP6_NF_IPTABLES || IP6_NF_IPTABLES=n)
536 depends on NETFILTER_ADVANCED
538 This option adds the "HMARK" target.
540 The target allows you to create rules in the "raw" and "mangle" tables
541 which set the skbuff mark by means of hash calculation within a given
542 range. The nfmark can influence the routing method (see "Use netfilter
543 MARK value as routing key") and can also be used by other subsystems to
544 change their behaviour.
546 To compile it as a module, choose M here. If unsure, say N.
548 config NETFILTER_XT_TARGET_IDLETIMER
549 tristate "IDLETIMER target support"
550 depends on NETFILTER_ADVANCED
553 This option adds the `IDLETIMER' target. Each matching packet
554 resets the timer associated with label specified when the rule is
555 added. When the timer expires, it triggers a sysfs notification.
556 The remaining time for expiration can be read via sysfs.
558 To compile it as a module, choose M here. If unsure, say N.
560 config NETFILTER_XT_TARGET_LED
561 tristate '"LED" target support'
562 depends on LEDS_CLASS && LEDS_TRIGGERS
563 depends on NETFILTER_ADVANCED
565 This option adds a `LED' target, which allows you to blink LEDs in
566 response to particular packets passing through your machine.
568 This can be used to turn a spare LED into a network activity LED,
569 which only flashes in response to FTP transfers, for example. Or
570 you could have an LED which lights up for a minute or two every time
571 somebody connects to your machine via SSH.
573 You will need support for the "led" class to make this work.
575 To create an LED trigger for incoming SSH traffic:
576 iptables -A INPUT -p tcp --dport 22 -j LED --led-trigger-id ssh --led-delay 1000
578 Then attach the new trigger to an LED on your system:
579 echo netfilter-ssh > /sys/class/leds/<ledname>/trigger
581 For more information on the LEDs available on your system, see
582 Documentation/leds/leds-class.txt
584 config NETFILTER_XT_TARGET_LOG
585 tristate "LOG target support"
586 default m if NETFILTER_ADVANCED=n
588 This option adds a `LOG' target, which allows you to create rules in
589 any iptables table which records the packet header to the syslog.
591 To compile it as a module, choose M here. If unsure, say N.
593 config NETFILTER_XT_TARGET_MARK
594 tristate '"MARK" target support'
595 depends on NETFILTER_ADVANCED
596 select NETFILTER_XT_MARK
598 This is a backwards-compat option for the user's convenience
599 (e.g. when running oldconfig). It selects
600 CONFIG_NETFILTER_XT_MARK (combined mark/MARK module).
602 config NETFILTER_XT_TARGET_NFLOG
603 tristate '"NFLOG" target support'
604 default m if NETFILTER_ADVANCED=n
605 select NETFILTER_NETLINK_LOG
607 This option enables the NFLOG target, which allows to LOG
608 messages through nfnetlink_log.
610 To compile it as a module, choose M here. If unsure, say N.
612 config NETFILTER_XT_TARGET_NFQUEUE
613 tristate '"NFQUEUE" target Support'
614 depends on NETFILTER_ADVANCED
615 select NETFILTER_NETLINK_QUEUE
617 This target replaced the old obsolete QUEUE target.
619 As opposed to QUEUE, it supports 65535 different queues,
622 To compile it as a module, choose M here. If unsure, say N.
624 config NETFILTER_XT_TARGET_NOTRACK
625 tristate '"NOTRACK" target support'
626 depends on IP_NF_RAW || IP6_NF_RAW
627 depends on NF_CONNTRACK
629 The NOTRACK target allows a select rule to specify
630 which packets *not* to enter the conntrack/NAT
631 subsystem with all the consequences (no ICMP error tracking,
632 no protocol helpers for the selected packets).
634 If you want to compile it as a module, say M here and read
635 <file:Documentation/kbuild/modules.txt>. If unsure, say `N'.
637 config NETFILTER_XT_TARGET_RATEEST
638 tristate '"RATEEST" target support'
639 depends on NETFILTER_ADVANCED
641 This option adds a `RATEEST' target, which allows to measure
642 rates similar to TC estimators. The `rateest' match can be
643 used to match on the measured rates.
645 To compile it as a module, choose M here. If unsure, say N.
647 config NETFILTER_XT_TARGET_TEE
648 tristate '"TEE" - packet cloning to alternate destination'
649 depends on NETFILTER_ADVANCED
650 depends on (IPV6 || IPV6=n)
651 depends on !NF_CONNTRACK || NF_CONNTRACK
653 This option adds a "TEE" target with which a packet can be cloned and
654 this clone be rerouted to another nexthop.
656 config NETFILTER_XT_TARGET_TPROXY
657 tristate '"TPROXY" target support (EXPERIMENTAL)'
658 depends on EXPERIMENTAL
659 depends on NETFILTER_TPROXY
660 depends on NETFILTER_XTABLES
661 depends on NETFILTER_ADVANCED
662 select NF_DEFRAG_IPV4
663 select NF_DEFRAG_IPV6 if IP6_NF_IPTABLES
665 This option adds a `TPROXY' target, which is somewhat similar to
666 REDIRECT. It can only be used in the mangle table and is useful
667 to redirect traffic to a transparent proxy. It does _not_ depend
668 on Netfilter connection tracking and NAT, unlike REDIRECT.
670 To compile it as a module, choose M here. If unsure, say N.
672 config NETFILTER_XT_TARGET_TRACE
673 tristate '"TRACE" target support'
674 depends on IP_NF_RAW || IP6_NF_RAW
675 depends on NETFILTER_ADVANCED
677 The TRACE target allows you to mark packets so that the kernel
678 will log every rule which match the packets as those traverse
679 the tables, chains, rules.
681 If you want to compile it as a module, say M here and read
682 <file:Documentation/kbuild/modules.txt>. If unsure, say `N'.
684 config NETFILTER_XT_TARGET_SECMARK
685 tristate '"SECMARK" target support'
686 depends on NETWORK_SECMARK
687 default m if NETFILTER_ADVANCED=n
689 The SECMARK target allows security marking of network
690 packets, for use with security subsystems.
692 To compile it as a module, choose M here. If unsure, say N.
694 config NETFILTER_XT_TARGET_TCPMSS
695 tristate '"TCPMSS" target support'
696 depends on (IPV6 || IPV6=n)
697 default m if NETFILTER_ADVANCED=n
699 This option adds a `TCPMSS' target, which allows you to alter the
700 MSS value of TCP SYN packets, to control the maximum size for that
701 connection (usually limiting it to your outgoing interface's MTU
704 This is used to overcome criminally braindead ISPs or servers which
705 block ICMP Fragmentation Needed packets. The symptoms of this
706 problem are that everything works fine from your Linux
707 firewall/router, but machines behind it can never exchange large
709 1) Web browsers connect, then hang with no data received.
710 2) Small mail works fine, but large emails hang.
711 3) ssh works fine, but scp hangs after initial handshaking.
713 Workaround: activate this option and add a rule to your firewall
716 iptables -A FORWARD -p tcp --tcp-flags SYN,RST SYN \
717 -j TCPMSS --clamp-mss-to-pmtu
719 To compile it as a module, choose M here. If unsure, say N.
721 config NETFILTER_XT_TARGET_TCPOPTSTRIP
722 tristate '"TCPOPTSTRIP" target support (EXPERIMENTAL)'
723 depends on EXPERIMENTAL
724 depends on IP_NF_MANGLE || IP6_NF_MANGLE
725 depends on NETFILTER_ADVANCED
727 This option adds a "TCPOPTSTRIP" target, which allows you to strip
728 TCP options from TCP packets.
730 # alphabetically ordered list of matches
732 comment "Xtables matches"
734 config NETFILTER_XT_MATCH_ADDRTYPE
735 tristate '"addrtype" address type match support'
736 depends on NETFILTER_ADVANCED
738 This option allows you to match what routing thinks of an address,
739 eg. UNICAST, LOCAL, BROADCAST, ...
741 If you want to compile it as a module, say M here and read
742 <file:Documentation/kbuild/modules.txt>. If unsure, say `N'.
744 config NETFILTER_XT_MATCH_CLUSTER
745 tristate '"cluster" match support'
746 depends on NF_CONNTRACK
747 depends on NETFILTER_ADVANCED
749 This option allows you to build work-load-sharing clusters of
750 network servers/stateful firewalls without having a dedicated
751 load-balancing router/server/switch. Basically, this match returns
752 true when the packet must be handled by this cluster node. Thus,
753 all nodes see all packets and this match decides which node handles
754 what packets. The work-load sharing algorithm is based on source
757 If you say Y or M here, try `iptables -m cluster --help` for
760 config NETFILTER_XT_MATCH_COMMENT
761 tristate '"comment" match support'
762 depends on NETFILTER_ADVANCED
764 This option adds a `comment' dummy-match, which allows you to put
765 comments in your iptables ruleset.
767 If you want to compile it as a module, say M here and read
768 <file:Documentation/kbuild/modules.txt>. If unsure, say `N'.
770 config NETFILTER_XT_MATCH_CONNBYTES
771 tristate '"connbytes" per-connection counter match support'
772 depends on NF_CONNTRACK
773 depends on NETFILTER_ADVANCED
775 This option adds a `connbytes' match, which allows you to match the
776 number of bytes and/or packets for each direction within a connection.
778 If you want to compile it as a module, say M here and read
779 <file:Documentation/kbuild/modules.txt>. If unsure, say `N'.
781 config NETFILTER_XT_MATCH_CONNLIMIT
782 tristate '"connlimit" match support"'
783 depends on NF_CONNTRACK
784 depends on NETFILTER_ADVANCED
786 This match allows you to match against the number of parallel
787 connections to a server per client IP address (or address block).
789 config NETFILTER_XT_MATCH_CONNMARK
790 tristate '"connmark" connection mark match support'
791 depends on NF_CONNTRACK
792 depends on NETFILTER_ADVANCED
793 select NETFILTER_XT_CONNMARK
795 This is a backwards-compat option for the user's convenience
796 (e.g. when running oldconfig). It selects
797 CONFIG_NETFILTER_XT_CONNMARK (combined connmark/CONNMARK module).
799 config NETFILTER_XT_MATCH_CONNTRACK
800 tristate '"conntrack" connection tracking match support'
801 depends on NF_CONNTRACK
802 default m if NETFILTER_ADVANCED=n
804 This is a general conntrack match module, a superset of the state match.
806 It allows matching on additional conntrack information, which is
807 useful in complex configurations, such as NAT gateways with multiple
808 internet links or tunnels.
810 To compile it as a module, choose M here. If unsure, say N.
812 config NETFILTER_XT_MATCH_CPU
813 tristate '"cpu" match support'
814 depends on NETFILTER_ADVANCED
816 CPU matching allows you to match packets based on the CPU
817 currently handling the packet.
819 To compile it as a module, choose M here. If unsure, say N.
821 config NETFILTER_XT_MATCH_DCCP
822 tristate '"dccp" protocol match support'
823 depends on NETFILTER_ADVANCED
826 With this option enabled, you will be able to use the iptables
827 `dccp' match in order to match on DCCP source/destination ports
830 If you want to compile it as a module, say M here and read
831 <file:Documentation/kbuild/modules.txt>. If unsure, say `N'.
833 config NETFILTER_XT_MATCH_DEVGROUP
834 tristate '"devgroup" match support'
835 depends on NETFILTER_ADVANCED
837 This options adds a `devgroup' match, which allows to match on the
838 device group a network device is assigned to.
840 To compile it as a module, choose M here. If unsure, say N.
842 config NETFILTER_XT_MATCH_DSCP
843 tristate '"dscp" and "tos" match support'
844 depends on NETFILTER_ADVANCED
846 This option adds a `DSCP' match, which allows you to match against
847 the IPv4/IPv6 header DSCP field (differentiated services codepoint).
849 The DSCP field can have any value between 0x0 and 0x3f inclusive.
851 It will also add a "tos" match, which allows you to match packets
852 based on the Type Of Service fields of the IPv4 packet (which share
853 the same bits as DSCP).
855 To compile it as a module, choose M here. If unsure, say N.
857 config NETFILTER_XT_MATCH_ECN
858 tristate '"ecn" match support'
859 depends on NETFILTER_ADVANCED
861 This option adds an "ECN" match, which allows you to match against
862 the IPv4 and TCP header ECN fields.
864 To compile it as a module, choose M here. If unsure, say N.
866 config NETFILTER_XT_MATCH_ESP
867 tristate '"esp" match support'
868 depends on NETFILTER_ADVANCED
870 This match extension allows you to match a range of SPIs
871 inside ESP header of IPSec packets.
873 To compile it as a module, choose M here. If unsure, say N.
875 config NETFILTER_XT_MATCH_HASHLIMIT
876 tristate '"hashlimit" match support'
877 depends on (IP6_NF_IPTABLES || IP6_NF_IPTABLES=n)
878 depends on NETFILTER_ADVANCED
880 This option adds a `hashlimit' match.
882 As opposed to `limit', this match dynamically creates a hash table
883 of limit buckets, based on your selection of source/destination
884 addresses and/or ports.
886 It enables you to express policies like `10kpps for any given
887 destination address' or `500pps from any given source address'
890 config NETFILTER_XT_MATCH_HELPER
891 tristate '"helper" match support'
892 depends on NF_CONNTRACK
893 depends on NETFILTER_ADVANCED
895 Helper matching allows you to match packets in dynamic connections
896 tracked by a conntrack-helper, ie. ip_conntrack_ftp
898 To compile it as a module, choose M here. If unsure, say Y.
900 config NETFILTER_XT_MATCH_HL
901 tristate '"hl" hoplimit/TTL match support'
902 depends on NETFILTER_ADVANCED
904 HL matching allows you to match packets based on the hoplimit
905 in the IPv6 header, or the time-to-live field in the IPv4
906 header of the packet.
908 config NETFILTER_XT_MATCH_IPRANGE
909 tristate '"iprange" address range match support'
910 depends on NETFILTER_ADVANCED
912 This option adds a "iprange" match, which allows you to match based on
913 an IP address range. (Normal iptables only matches on single addresses
914 with an optional mask.)
918 config NETFILTER_XT_MATCH_IPVS
919 tristate '"ipvs" match support'
921 depends on NETFILTER_ADVANCED
922 depends on NF_CONNTRACK
924 This option allows you to match against IPVS properties of a packet.
928 config NETFILTER_XT_MATCH_LENGTH
929 tristate '"length" match support'
930 depends on NETFILTER_ADVANCED
932 This option allows you to match the length of a packet against a
933 specific value or range of values.
935 To compile it as a module, choose M here. If unsure, say N.
937 config NETFILTER_XT_MATCH_LIMIT
938 tristate '"limit" match support'
939 depends on NETFILTER_ADVANCED
941 limit matching allows you to control the rate at which a rule can be
942 matched: mainly useful in combination with the LOG target ("LOG
943 target support", below) and to avoid some Denial of Service attacks.
945 To compile it as a module, choose M here. If unsure, say N.
947 config NETFILTER_XT_MATCH_MAC
948 tristate '"mac" address match support'
949 depends on NETFILTER_ADVANCED
951 MAC matching allows you to match packets based on the source
952 Ethernet address of the packet.
954 To compile it as a module, choose M here. If unsure, say N.
956 config NETFILTER_XT_MATCH_MARK
957 tristate '"mark" match support'
958 depends on NETFILTER_ADVANCED
959 select NETFILTER_XT_MARK
961 This is a backwards-compat option for the user's convenience
962 (e.g. when running oldconfig). It selects
963 CONFIG_NETFILTER_XT_MARK (combined mark/MARK module).
965 config NETFILTER_XT_MATCH_MULTIPORT
966 tristate '"multiport" Multiple port match support'
967 depends on NETFILTER_ADVANCED
969 Multiport matching allows you to match TCP or UDP packets based on
970 a series of source or destination ports: normally a rule can only
971 match a single range of ports.
973 To compile it as a module, choose M here. If unsure, say N.
975 config NETFILTER_XT_MATCH_NFACCT
976 tristate '"nfacct" match support'
977 depends on NETFILTER_ADVANCED
978 select NETFILTER_NETLINK_ACCT
980 This option allows you to use the extended accounting through
983 To compile it as a module, choose M here. If unsure, say N.
985 config NETFILTER_XT_MATCH_OSF
986 tristate '"osf" Passive OS fingerprint match'
987 depends on NETFILTER_ADVANCED && NETFILTER_NETLINK
989 This option selects the Passive OS Fingerprinting match module
990 that allows to passively match the remote operating system by
991 analyzing incoming TCP SYN packets.
993 Rules and loading software can be downloaded from
994 http://www.ioremap.net/projects/osf
996 To compile it as a module, choose M here. If unsure, say N.
998 config NETFILTER_XT_MATCH_OWNER
999 tristate '"owner" match support'
1000 depends on NETFILTER_ADVANCED
1002 Socket owner matching allows you to match locally-generated packets
1003 based on who created the socket: the user or group. It is also
1004 possible to check whether a socket actually exists.
1006 config NETFILTER_XT_MATCH_POLICY
1007 tristate 'IPsec "policy" match support'
1009 default m if NETFILTER_ADVANCED=n
1011 Policy matching allows you to match packets based on the
1012 IPsec policy that was used during decapsulation/will
1013 be used during encapsulation.
1015 To compile it as a module, choose M here. If unsure, say N.
1017 config NETFILTER_XT_MATCH_PHYSDEV
1018 tristate '"physdev" match support'
1019 depends on BRIDGE && BRIDGE_NETFILTER
1020 depends on NETFILTER_ADVANCED
1022 Physdev packet matching matches against the physical bridge ports
1023 the IP packet arrived on or will leave by.
1025 To compile it as a module, choose M here. If unsure, say N.
1027 config NETFILTER_XT_MATCH_PKTTYPE
1028 tristate '"pkttype" packet type match support'
1029 depends on NETFILTER_ADVANCED
1031 Packet type matching allows you to match a packet by
1032 its "class", eg. BROADCAST, MULTICAST, ...
1035 iptables -A INPUT -m pkttype --pkt-type broadcast -j LOG
1037 To compile it as a module, choose M here. If unsure, say N.
1039 config NETFILTER_XT_MATCH_QUOTA
1040 tristate '"quota" match support'
1041 depends on NETFILTER_ADVANCED
1043 This option adds a `quota' match, which allows to match on a
1046 If you want to compile it as a module, say M here and read
1047 <file:Documentation/kbuild/modules.txt>. If unsure, say `N'.
1049 config NETFILTER_XT_MATCH_RATEEST
1050 tristate '"rateest" match support'
1051 depends on NETFILTER_ADVANCED
1052 select NETFILTER_XT_TARGET_RATEEST
1054 This option adds a `rateest' match, which allows to match on the
1055 rate estimated by the RATEEST target.
1057 To compile it as a module, choose M here. If unsure, say N.
1059 config NETFILTER_XT_MATCH_REALM
1060 tristate '"realm" match support'
1061 depends on NETFILTER_ADVANCED
1062 select IP_ROUTE_CLASSID
1064 This option adds a `realm' match, which allows you to use the realm
1065 key from the routing subsystem inside iptables.
1067 This match pretty much resembles the CONFIG_NET_CLS_ROUTE4 option
1070 If you want to compile it as a module, say M here and read
1071 <file:Documentation/kbuild/modules.txt>. If unsure, say `N'.
1073 config NETFILTER_XT_MATCH_RECENT
1074 tristate '"recent" match support'
1075 depends on NETFILTER_ADVANCED
1077 This match is used for creating one or many lists of recently
1078 used addresses and then matching against that/those list(s).
1080 Short options are available by using 'iptables -m recent -h'
1081 Official Website: <http://snowman.net/projects/ipt_recent/>
1083 config NETFILTER_XT_MATCH_SCTP
1084 tristate '"sctp" protocol match support (EXPERIMENTAL)'
1085 depends on EXPERIMENTAL
1086 depends on NETFILTER_ADVANCED
1089 With this option enabled, you will be able to use the
1090 `sctp' match in order to match on SCTP source/destination ports
1091 and SCTP chunk types.
1093 If you want to compile it as a module, say M here and read
1094 <file:Documentation/kbuild/modules.txt>. If unsure, say `N'.
1096 config NETFILTER_XT_MATCH_SOCKET
1097 tristate '"socket" match support (EXPERIMENTAL)'
1098 depends on EXPERIMENTAL
1099 depends on NETFILTER_TPROXY
1100 depends on NETFILTER_XTABLES
1101 depends on NETFILTER_ADVANCED
1102 depends on !NF_CONNTRACK || NF_CONNTRACK
1103 select NF_DEFRAG_IPV4
1104 select NF_DEFRAG_IPV6 if IP6_NF_IPTABLES
1106 This option adds a `socket' match, which can be used to match
1107 packets for which a TCP or UDP socket lookup finds a valid socket.
1108 It can be used in combination with the MARK target and policy
1109 routing to implement full featured non-locally bound sockets.
1111 To compile it as a module, choose M here. If unsure, say N.
1113 config NETFILTER_XT_MATCH_STATE
1114 tristate '"state" match support'
1115 depends on NF_CONNTRACK
1116 default m if NETFILTER_ADVANCED=n
1118 Connection state matching allows you to match packets based on their
1119 relationship to a tracked connection (ie. previous packets). This
1120 is a powerful tool for packet classification.
1122 To compile it as a module, choose M here. If unsure, say N.
1124 config NETFILTER_XT_MATCH_STATISTIC
1125 tristate '"statistic" match support'
1126 depends on NETFILTER_ADVANCED
1128 This option adds a `statistic' match, which allows you to match
1129 on packets periodically or randomly with a given percentage.
1131 To compile it as a module, choose M here. If unsure, say N.
1133 config NETFILTER_XT_MATCH_STRING
1134 tristate '"string" match support'
1135 depends on NETFILTER_ADVANCED
1137 select TEXTSEARCH_KMP
1138 select TEXTSEARCH_BM
1139 select TEXTSEARCH_FSM
1141 This option adds a `string' match, which allows you to look for
1142 pattern matchings in packets.
1144 To compile it as a module, choose M here. If unsure, say N.
1146 config NETFILTER_XT_MATCH_TCPMSS
1147 tristate '"tcpmss" match support'
1148 depends on NETFILTER_ADVANCED
1150 This option adds a `tcpmss' match, which allows you to examine the
1151 MSS value of TCP SYN packets, which control the maximum packet size
1152 for that connection.
1154 To compile it as a module, choose M here. If unsure, say N.
1156 config NETFILTER_XT_MATCH_TIME
1157 tristate '"time" match support'
1158 depends on NETFILTER_ADVANCED
1160 This option adds a "time" match, which allows you to match based on
1161 the packet arrival time (at the machine which netfilter is running)
1162 on) or departure time/date (for locally generated packets).
1164 If you say Y here, try `iptables -m time --help` for
1167 If you want to compile it as a module, say M here.
1170 config NETFILTER_XT_MATCH_U32
1171 tristate '"u32" match support'
1172 depends on NETFILTER_ADVANCED
1174 u32 allows you to extract quantities of up to 4 bytes from a packet,
1175 AND them with specified masks, shift them by specified amounts and
1176 test whether the results are in any of a set of specified ranges.
1177 The specification of what to extract is general enough to skip over
1178 headers with lengths stored in the packet, as in IP or TCP header
1181 Details and examples are in the kernel module source.
1183 endif # NETFILTER_XTABLES
1187 source "net/netfilter/ipset/Kconfig"
1189 source "net/netfilter/ipvs/Kconfig"