xref: /openbmc/linux/net/netfilter/Kconfig (revision 25985edc)
1menu "Core Netfilter Configuration"
2	depends on NET && INET && NETFILTER
3
4config NETFILTER_NETLINK
5	tristate
6
7config NETFILTER_NETLINK_QUEUE
8	tristate "Netfilter NFQUEUE over NFNETLINK interface"
9	depends on NETFILTER_ADVANCED
10	select NETFILTER_NETLINK
11	help
12	  If this option is enabled, the kernel will include support
13	  for queueing packets via NFNETLINK.
14
15config NETFILTER_NETLINK_LOG
16	tristate "Netfilter LOG over NFNETLINK interface"
17	default m if NETFILTER_ADVANCED=n
18	select NETFILTER_NETLINK
19	help
20	  If this option is enabled, the kernel will include support
21	  for logging packets via NFNETLINK.
22
23	  This obsoletes the existing ipt_ULOG and ebg_ulog mechanisms,
24	  and is also scheduled to replace the old syslog-based ipt_LOG
25	  and ip6t_LOG modules.
26
27config NF_CONNTRACK
28	tristate "Netfilter connection tracking support"
29	default m if NETFILTER_ADVANCED=n
30	help
31	  Connection tracking keeps a record of what packets have passed
32	  through your machine, in order to figure out how they are related
33	  into connections.
34
35	  This is required to do Masquerading or other kinds of Network
36	  Address Translation.  It can also be used to enhance packet
37	  filtering (see `Connection state match support' below).
38
39	  To compile it as a module, choose M here.  If unsure, say N.
40
41if NF_CONNTRACK
42
43config NF_CONNTRACK_MARK
44	bool  'Connection mark tracking support'
45	depends on NETFILTER_ADVANCED
46	help
47	  This option enables support for connection marks, used by the
48	  `CONNMARK' target and `connmark' match. Similar to the mark value
49	  of packets, but this mark value is kept in the conntrack session
50	  instead of the individual packets.
51
52config NF_CONNTRACK_SECMARK
53	bool  'Connection tracking security mark support'
54	depends on NETWORK_SECMARK
55	default m if NETFILTER_ADVANCED=n
56	help
57	  This option enables security markings to be applied to
58	  connections.  Typically they are copied to connections from
59	  packets using the CONNSECMARK target and copied back from
60	  connections to packets with the same target, with the packets
61	  being originally labeled via SECMARK.
62
63	  If unsure, say 'N'.
64
65config NF_CONNTRACK_ZONES
66	bool  'Connection tracking zones'
67	depends on NETFILTER_ADVANCED
68	depends on NETFILTER_XT_TARGET_CT
69	help
70	  This option enables support for connection tracking zones.
71	  Normally, each connection needs to have a unique system wide
72	  identity. Connection tracking zones allow to have multiple
73	  connections using the same identity, as long as they are
74	  contained in different zones.
75
76	  If unsure, say `N'.
77
78config NF_CONNTRACK_EVENTS
79	bool "Connection tracking events"
80	depends on NETFILTER_ADVANCED
81	help
82	  If this option is enabled, the connection tracking code will
83	  provide a notifier chain that can be used by other kernel code
84	  to get notified about changes in the connection tracking state.
85
86	  If unsure, say `N'.
87
88config NF_CONNTRACK_TIMESTAMP
89	bool  'Connection tracking timestamping'
90	depends on NETFILTER_ADVANCED
91	help
92	  This option enables support for connection tracking timestamping.
93	  This allows you to store the flow start-time and to obtain
94	  the flow-stop time (once it has been destroyed) via Connection
95	  tracking events.
96
97	  If unsure, say `N'.
98
99config NF_CT_PROTO_DCCP
100	tristate 'DCCP protocol connection tracking support (EXPERIMENTAL)'
101	depends on EXPERIMENTAL
102	depends on NETFILTER_ADVANCED
103	default IP_DCCP
104	help
105	  With this option enabled, the layer 3 independent connection
106	  tracking code will be able to do state tracking on DCCP connections.
107
108	  If unsure, say 'N'.
109
110config NF_CT_PROTO_GRE
111	tristate
112
113config NF_CT_PROTO_SCTP
114	tristate 'SCTP protocol connection tracking support (EXPERIMENTAL)'
115	depends on EXPERIMENTAL
116	depends on NETFILTER_ADVANCED
117	default IP_SCTP
118	help
119	  With this option enabled, the layer 3 independent connection
120	  tracking code will be able to do state tracking on SCTP connections.
121
122	  If you want to compile it as a module, say M here and read
123	  <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.
124
125config NF_CT_PROTO_UDPLITE
126	tristate 'UDP-Lite protocol connection tracking support'
127	depends on NETFILTER_ADVANCED
128	help
129	  With this option enabled, the layer 3 independent connection
130	  tracking code will be able to do state tracking on UDP-Lite
131	  connections.
132
133	  To compile it as a module, choose M here.  If unsure, say N.
134
135config NF_CONNTRACK_AMANDA
136	tristate "Amanda backup protocol support"
137	depends on NETFILTER_ADVANCED
138	select TEXTSEARCH
139	select TEXTSEARCH_KMP
140	help
141	  If you are running the Amanda backup package <http://www.amanda.org/>
142	  on this machine or machines that will be MASQUERADED through this
143	  machine, then you may want to enable this feature.  This allows the
144	  connection tracking and natting code to allow the sub-channels that
145	  Amanda requires for communication of the backup data, messages and
146	  index.
147
148	  To compile it as a module, choose M here.  If unsure, say N.
149
150config NF_CONNTRACK_FTP
151	tristate "FTP protocol support"
152	default m if NETFILTER_ADVANCED=n
153	help
154	  Tracking FTP connections is problematic: special helpers are
155	  required for tracking them, and doing masquerading and other forms
156	  of Network Address Translation on them.
157
158	  This is FTP support on Layer 3 independent connection tracking.
159	  Layer 3 independent connection tracking is experimental scheme
160	  which generalize ip_conntrack to support other layer 3 protocols.
161
162	  To compile it as a module, choose M here.  If unsure, say N.
163
164config NF_CONNTRACK_H323
165	tristate "H.323 protocol support"
166	depends on (IPV6 || IPV6=n)
167	depends on NETFILTER_ADVANCED
168	help
169	  H.323 is a VoIP signalling protocol from ITU-T. As one of the most
170	  important VoIP protocols, it is widely used by voice hardware and
171	  software including voice gateways, IP phones, Netmeeting, OpenPhone,
172	  Gnomemeeting, etc.
173
174	  With this module you can support H.323 on a connection tracking/NAT
175	  firewall.
176
177	  This module supports RAS, Fast Start, H.245 Tunnelling, Call
178	  Forwarding, RTP/RTCP and T.120 based audio, video, fax, chat,
179	  whiteboard, file transfer, etc. For more information, please
180	  visit http://nath323.sourceforge.net/.
181
182	  To compile it as a module, choose M here.  If unsure, say N.
183
184config NF_CONNTRACK_IRC
185	tristate "IRC protocol support"
186	default m if NETFILTER_ADVANCED=n
187	help
188	  There is a commonly-used extension to IRC called
189	  Direct Client-to-Client Protocol (DCC).  This enables users to send
190	  files to each other, and also chat to each other without the need
191	  of a server.  DCC Sending is used anywhere you send files over IRC,
192	  and DCC Chat is most commonly used by Eggdrop bots.  If you are
193	  using NAT, this extension will enable you to send files and initiate
194	  chats.  Note that you do NOT need this extension to get files or
195	  have others initiate chats, or everything else in IRC.
196
197	  To compile it as a module, choose M here.  If unsure, say N.
198
199config NF_CONNTRACK_BROADCAST
200	tristate
201
202config NF_CONNTRACK_NETBIOS_NS
203	tristate "NetBIOS name service protocol support"
204	depends on NETFILTER_ADVANCED
205	select NF_CONNTRACK_BROADCAST
206	help
207	  NetBIOS name service requests are sent as broadcast messages from an
208	  unprivileged port and responded to with unicast messages to the
209	  same port. This make them hard to firewall properly because connection
210	  tracking doesn't deal with broadcasts. This helper tracks locally
211	  originating NetBIOS name service requests and the corresponding
212	  responses. It relies on correct IP address configuration, specifically
213	  netmask and broadcast address. When properly configured, the output
214	  of "ip address show" should look similar to this:
215
216	  $ ip -4 address show eth0
217	  4: eth0: <BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 1000
218	      inet 172.16.2.252/24 brd 172.16.2.255 scope global eth0
219
220	  To compile it as a module, choose M here.  If unsure, say N.
221
222config NF_CONNTRACK_SNMP
223	tristate "SNMP service protocol support"
224	depends on NETFILTER_ADVANCED
225	select NF_CONNTRACK_BROADCAST
226	help
227	  SNMP service requests are sent as broadcast messages from an
228	  unprivileged port and responded to with unicast messages to the
229	  same port. This make them hard to firewall properly because connection
230	  tracking doesn't deal with broadcasts. This helper tracks locally
231	  originating SNMP service requests and the corresponding
232	  responses. It relies on correct IP address configuration, specifically
233	  netmask and broadcast address.
234
235	  To compile it as a module, choose M here.  If unsure, say N.
236
237config NF_CONNTRACK_PPTP
238	tristate "PPtP protocol support"
239	depends on NETFILTER_ADVANCED
240	select NF_CT_PROTO_GRE
241	help
242	  This module adds support for PPTP (Point to Point Tunnelling
243	  Protocol, RFC2637) connection tracking and NAT.
244
245	  If you are running PPTP sessions over a stateful firewall or NAT
246	  box, you may want to enable this feature.
247
248	  Please note that not all PPTP modes of operation are supported yet.
249	  Specifically these limitations exist:
250	    - Blindly assumes that control connections are always established
251	      in PNS->PAC direction. This is a violation of RFC2637.
252	    - Only supports a single call within each session
253
254	  To compile it as a module, choose M here.  If unsure, say N.
255
256config NF_CONNTRACK_SANE
257	tristate "SANE protocol support (EXPERIMENTAL)"
258	depends on EXPERIMENTAL
259	depends on NETFILTER_ADVANCED
260	help
261	  SANE is a protocol for remote access to scanners as implemented
262	  by the 'saned' daemon. Like FTP, it uses separate control and
263	  data connections.
264
265	  With this module you can support SANE on a connection tracking
266	  firewall.
267
268	  To compile it as a module, choose M here.  If unsure, say N.
269
270config NF_CONNTRACK_SIP
271	tristate "SIP protocol support"
272	default m if NETFILTER_ADVANCED=n
273	help
274	  SIP is an application-layer control protocol that can establish,
275	  modify, and terminate multimedia sessions (conferences) such as
276	  Internet telephony calls. With the ip_conntrack_sip and
277	  the nf_nat_sip modules you can support the protocol on a connection
278	  tracking/NATing firewall.
279
280	  To compile it as a module, choose M here.  If unsure, say N.
281
282config NF_CONNTRACK_TFTP
283	tristate "TFTP protocol support"
284	depends on NETFILTER_ADVANCED
285	help
286	  TFTP connection tracking helper, this is required depending
287	  on how restrictive your ruleset is.
288	  If you are using a tftp client behind -j SNAT or -j MASQUERADING
289	  you will need this.
290
291	  To compile it as a module, choose M here.  If unsure, say N.
292
293config NF_CT_NETLINK
294	tristate 'Connection tracking netlink interface'
295	select NETFILTER_NETLINK
296	default m if NETFILTER_ADVANCED=n
297	help
298	  This option enables support for a netlink-based userspace interface
299
300endif # NF_CONNTRACK
301
302# transparent proxy support
303config NETFILTER_TPROXY
304	tristate "Transparent proxying support (EXPERIMENTAL)"
305	depends on EXPERIMENTAL
306	depends on IP_NF_MANGLE
307	depends on NETFILTER_ADVANCED
308	help
309	  This option enables transparent proxying support, that is,
310	  support for handling non-locally bound IPv4 TCP and UDP sockets.
311	  For it to work you will have to configure certain iptables rules
312	  and use policy routing. For more information on how to set it up
313	  see Documentation/networking/tproxy.txt.
314
315	  To compile it as a module, choose M here.  If unsure, say N.
316
317config NETFILTER_XTABLES
318	tristate "Netfilter Xtables support (required for ip_tables)"
319	default m if NETFILTER_ADVANCED=n
320	help
321	  This is required if you intend to use any of ip_tables,
322	  ip6_tables or arp_tables.
323
324if NETFILTER_XTABLES
325
326comment "Xtables combined modules"
327
328config NETFILTER_XT_MARK
329	tristate 'nfmark target and match support'
330	default m if NETFILTER_ADVANCED=n
331	---help---
332	This option adds the "MARK" target and "mark" match.
333
334	Netfilter mark matching allows you to match packets based on the
335	"nfmark" value in the packet.
336	The target allows you to create rules in the "mangle" table which alter
337	the netfilter mark (nfmark) field associated with the packet.
338
339	Prior to routing, the nfmark can influence the routing method (see
340	"Use netfilter MARK value as routing key") and can also be used by
341	other subsystems to change their behavior.
342
343config NETFILTER_XT_CONNMARK
344	tristate 'ctmark target and match support'
345	depends on NF_CONNTRACK
346	depends on NETFILTER_ADVANCED
347	select NF_CONNTRACK_MARK
348	---help---
349	This option adds the "CONNMARK" target and "connmark" match.
350
351	Netfilter allows you to store a mark value per connection (a.k.a.
352	ctmark), similarly to the packet mark (nfmark). Using this
353	target and match, you can set and match on this mark.
354
355config NETFILTER_XT_SET
356	tristate 'set target and match support'
357	depends on IP_SET
358	depends on NETFILTER_ADVANCED
359	help
360	  This option adds the "SET" target and "set" match.
361
362	  Using this target and match, you can add/delete and match
363	  elements in the sets created by ipset(8).
364
365	  To compile it as a module, choose M here.  If unsure, say N.
366
367# alphabetically ordered list of targets
368
369comment "Xtables targets"
370
371config NETFILTER_XT_TARGET_AUDIT
372	tristate "AUDIT target support"
373	depends on AUDIT
374	depends on NETFILTER_ADVANCED
375	---help---
376	  This option adds a 'AUDIT' target, which can be used to create
377	  audit records for packets dropped/accepted.
378
379	  To compileit as a module, choose M here. If unsure, say N.
380
381config NETFILTER_XT_TARGET_CHECKSUM
382	tristate "CHECKSUM target support"
383	depends on IP_NF_MANGLE || IP6_NF_MANGLE
384	depends on NETFILTER_ADVANCED
385	---help---
386	  This option adds a `CHECKSUM' target, which can be used in the iptables mangle
387	  table.
388
389	  You can use this target to compute and fill in the checksum in
390	  a packet that lacks a checksum.  This is particularly useful,
391	  if you need to work around old applications such as dhcp clients,
392	  that do not work well with checksum offloads, but don't want to disable
393	  checksum offload in your device.
394
395	  To compile it as a module, choose M here.  If unsure, say N.
396
397config NETFILTER_XT_TARGET_CLASSIFY
398	tristate '"CLASSIFY" target support'
399	depends on NETFILTER_ADVANCED
400	help
401	  This option adds a `CLASSIFY' target, which enables the user to set
402	  the priority of a packet. Some qdiscs can use this value for
403	  classification, among these are:
404
405  	  atm, cbq, dsmark, pfifo_fast, htb, prio
406
407	  To compile it as a module, choose M here.  If unsure, say N.
408
409config NETFILTER_XT_TARGET_CONNMARK
410	tristate  '"CONNMARK" target support'
411	depends on NF_CONNTRACK
412	depends on NETFILTER_ADVANCED
413	select NETFILTER_XT_CONNMARK
414	---help---
415	This is a backwards-compat option for the user's convenience
416	(e.g. when running oldconfig). It selects
417	CONFIG_NETFILTER_XT_CONNMARK (combined connmark/CONNMARK module).
418
419config NETFILTER_XT_TARGET_CONNSECMARK
420	tristate '"CONNSECMARK" target support'
421	depends on NF_CONNTRACK && NF_CONNTRACK_SECMARK
422	default m if NETFILTER_ADVANCED=n
423	help
424	  The CONNSECMARK target copies security markings from packets
425	  to connections, and restores security markings from connections
426	  to packets (if the packets are not already marked).  This would
427	  normally be used in conjunction with the SECMARK target.
428
429	  To compile it as a module, choose M here.  If unsure, say N.
430
431config NETFILTER_XT_TARGET_CT
432	tristate '"CT" target support'
433	depends on NF_CONNTRACK
434	depends on IP_NF_RAW || IP6_NF_RAW
435	depends on NETFILTER_ADVANCED
436	help
437	  This options adds a `CT' target, which allows to specify initial
438	  connection tracking parameters like events to be delivered and
439	  the helper to be used.
440
441	  To compile it as a module, choose M here.  If unsure, say N.
442
443config NETFILTER_XT_TARGET_DSCP
444	tristate '"DSCP" and "TOS" target support'
445	depends on IP_NF_MANGLE || IP6_NF_MANGLE
446	depends on NETFILTER_ADVANCED
447	help
448	  This option adds a `DSCP' target, which allows you to manipulate
449	  the IPv4/IPv6 header DSCP field (differentiated services codepoint).
450
451	  The DSCP field can have any value between 0x0 and 0x3f inclusive.
452
453	  It also adds the "TOS" target, which allows you to create rules in
454	  the "mangle" table which alter the Type Of Service field of an IPv4
455	  or the Priority field of an IPv6 packet, prior to routing.
456
457	  To compile it as a module, choose M here.  If unsure, say N.
458
459config NETFILTER_XT_TARGET_HL
460	tristate '"HL" hoplimit target support'
461	depends on IP_NF_MANGLE || IP6_NF_MANGLE
462	depends on NETFILTER_ADVANCED
463	---help---
464	This option adds the "HL" (for IPv6) and "TTL" (for IPv4)
465	targets, which enable the user to change the
466	hoplimit/time-to-live value of the IP header.
467
468	While it is safe to decrement the hoplimit/TTL value, the
469	modules also allow to increment and set the hoplimit value of
470	the header to arbitrary values. This is EXTREMELY DANGEROUS
471	since you can easily create immortal packets that loop
472	forever on the network.
473
474config NETFILTER_XT_TARGET_IDLETIMER
475	tristate  "IDLETIMER target support"
476	depends on NETFILTER_ADVANCED
477	help
478
479	  This option adds the `IDLETIMER' target.  Each matching packet
480	  resets the timer associated with label specified when the rule is
481	  added.  When the timer expires, it triggers a sysfs notification.
482	  The remaining time for expiration can be read via sysfs.
483
484	  To compile it as a module, choose M here.  If unsure, say N.
485
486config NETFILTER_XT_TARGET_LED
487	tristate '"LED" target support'
488	depends on LEDS_CLASS && LEDS_TRIGGERS
489	depends on NETFILTER_ADVANCED
490	help
491	  This option adds a `LED' target, which allows you to blink LEDs in
492	  response to particular packets passing through your machine.
493
494	  This can be used to turn a spare LED into a network activity LED,
495	  which only flashes in response to FTP transfers, for example.  Or
496	  you could have an LED which lights up for a minute or two every time
497	  somebody connects to your machine via SSH.
498
499	  You will need support for the "led" class to make this work.
500
501	  To create an LED trigger for incoming SSH traffic:
502	    iptables -A INPUT -p tcp --dport 22 -j LED --led-trigger-id ssh --led-delay 1000
503
504	  Then attach the new trigger to an LED on your system:
505	    echo netfilter-ssh > /sys/class/leds/<ledname>/trigger
506
507	  For more information on the LEDs available on your system, see
508	  Documentation/leds-class.txt
509
510config NETFILTER_XT_TARGET_MARK
511	tristate '"MARK" target support'
512	depends on NETFILTER_ADVANCED
513	select NETFILTER_XT_MARK
514	---help---
515	This is a backwards-compat option for the user's convenience
516	(e.g. when running oldconfig). It selects
517	CONFIG_NETFILTER_XT_MARK (combined mark/MARK module).
518
519config NETFILTER_XT_TARGET_NFLOG
520	tristate '"NFLOG" target support'
521	default m if NETFILTER_ADVANCED=n
522	select NETFILTER_NETLINK_LOG
523	help
524	  This option enables the NFLOG target, which allows to LOG
525	  messages through nfnetlink_log.
526
527	  To compile it as a module, choose M here.  If unsure, say N.
528
529config NETFILTER_XT_TARGET_NFQUEUE
530	tristate '"NFQUEUE" target Support'
531	depends on NETFILTER_ADVANCED
532	select NETFILTER_NETLINK_QUEUE
533	help
534	  This target replaced the old obsolete QUEUE target.
535
536	  As opposed to QUEUE, it supports 65535 different queues,
537	  not just one.
538
539	  To compile it as a module, choose M here.  If unsure, say N.
540
541config NETFILTER_XT_TARGET_NOTRACK
542	tristate  '"NOTRACK" target support'
543	depends on IP_NF_RAW || IP6_NF_RAW
544	depends on NF_CONNTRACK
545	depends on NETFILTER_ADVANCED
546	help
547	  The NOTRACK target allows a select rule to specify
548	  which packets *not* to enter the conntrack/NAT
549	  subsystem with all the consequences (no ICMP error tracking,
550	  no protocol helpers for the selected packets).
551
552	  If you want to compile it as a module, say M here and read
553	  <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.
554
555config NETFILTER_XT_TARGET_RATEEST
556	tristate '"RATEEST" target support'
557	depends on NETFILTER_ADVANCED
558	help
559	  This option adds a `RATEEST' target, which allows to measure
560	  rates similar to TC estimators. The `rateest' match can be
561	  used to match on the measured rates.
562
563	  To compile it as a module, choose M here.  If unsure, say N.
564
565config NETFILTER_XT_TARGET_TEE
566	tristate '"TEE" - packet cloning to alternate destination'
567	depends on NETFILTER_ADVANCED
568	depends on (IPV6 || IPV6=n)
569	depends on !NF_CONNTRACK || NF_CONNTRACK
570	---help---
571	This option adds a "TEE" target with which a packet can be cloned and
572	this clone be rerouted to another nexthop.
573
574config NETFILTER_XT_TARGET_TPROXY
575	tristate '"TPROXY" target support (EXPERIMENTAL)'
576	depends on EXPERIMENTAL
577	depends on NETFILTER_TPROXY
578	depends on NETFILTER_XTABLES
579	depends on NETFILTER_ADVANCED
580	select NF_DEFRAG_IPV4
581	select NF_DEFRAG_IPV6 if IP6_NF_IPTABLES
582	help
583	  This option adds a `TPROXY' target, which is somewhat similar to
584	  REDIRECT.  It can only be used in the mangle table and is useful
585	  to redirect traffic to a transparent proxy.  It does _not_ depend
586	  on Netfilter connection tracking and NAT, unlike REDIRECT.
587
588	  To compile it as a module, choose M here.  If unsure, say N.
589
590config NETFILTER_XT_TARGET_TRACE
591	tristate  '"TRACE" target support'
592	depends on IP_NF_RAW || IP6_NF_RAW
593	depends on NETFILTER_ADVANCED
594	help
595	  The TRACE target allows you to mark packets so that the kernel
596	  will log every rule which match the packets as those traverse
597	  the tables, chains, rules.
598
599	  If you want to compile it as a module, say M here and read
600	  <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.
601
602config NETFILTER_XT_TARGET_SECMARK
603	tristate '"SECMARK" target support'
604	depends on NETWORK_SECMARK
605	default m if NETFILTER_ADVANCED=n
606	help
607	  The SECMARK target allows security marking of network
608	  packets, for use with security subsystems.
609
610	  To compile it as a module, choose M here.  If unsure, say N.
611
612config NETFILTER_XT_TARGET_TCPMSS
613	tristate '"TCPMSS" target support'
614	depends on (IPV6 || IPV6=n)
615	default m if NETFILTER_ADVANCED=n
616	---help---
617	  This option adds a `TCPMSS' target, which allows you to alter the
618	  MSS value of TCP SYN packets, to control the maximum size for that
619	  connection (usually limiting it to your outgoing interface's MTU
620	  minus 40).
621
622	  This is used to overcome criminally braindead ISPs or servers which
623	  block ICMP Fragmentation Needed packets.  The symptoms of this
624	  problem are that everything works fine from your Linux
625	  firewall/router, but machines behind it can never exchange large
626	  packets:
627	        1) Web browsers connect, then hang with no data received.
628	        2) Small mail works fine, but large emails hang.
629	        3) ssh works fine, but scp hangs after initial handshaking.
630
631	  Workaround: activate this option and add a rule to your firewall
632	  configuration like:
633
634	  iptables -A FORWARD -p tcp --tcp-flags SYN,RST SYN \
635	                 -j TCPMSS --clamp-mss-to-pmtu
636
637	  To compile it as a module, choose M here.  If unsure, say N.
638
639config NETFILTER_XT_TARGET_TCPOPTSTRIP
640	tristate '"TCPOPTSTRIP" target support (EXPERIMENTAL)'
641	depends on EXPERIMENTAL
642	depends on IP_NF_MANGLE || IP6_NF_MANGLE
643	depends on NETFILTER_ADVANCED
644	help
645	  This option adds a "TCPOPTSTRIP" target, which allows you to strip
646	  TCP options from TCP packets.
647
648# alphabetically ordered list of matches
649
650comment "Xtables matches"
651
652config NETFILTER_XT_MATCH_ADDRTYPE
653	tristate '"addrtype" address type match support'
654	depends on NETFILTER_ADVANCED
655	depends on (IPV6 || IPV6=n)
656	---help---
657	  This option allows you to match what routing thinks of an address,
658	  eg. UNICAST, LOCAL, BROADCAST, ...
659
660	  If you want to compile it as a module, say M here and read
661	  <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.
662
663config NETFILTER_XT_MATCH_CLUSTER
664	tristate '"cluster" match support'
665	depends on NF_CONNTRACK
666	depends on NETFILTER_ADVANCED
667	---help---
668	  This option allows you to build work-load-sharing clusters of
669	  network servers/stateful firewalls without having a dedicated
670	  load-balancing router/server/switch. Basically, this match returns
671	  true when the packet must be handled by this cluster node. Thus,
672	  all nodes see all packets and this match decides which node handles
673	  what packets. The work-load sharing algorithm is based on source
674	  address hashing.
675
676	  If you say Y or M here, try `iptables -m cluster --help` for
677	  more information.
678
679config NETFILTER_XT_MATCH_COMMENT
680	tristate  '"comment" match support'
681	depends on NETFILTER_ADVANCED
682	help
683	  This option adds a `comment' dummy-match, which allows you to put
684	  comments in your iptables ruleset.
685
686	  If you want to compile it as a module, say M here and read
687	  <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.
688
689config NETFILTER_XT_MATCH_CONNBYTES
690	tristate  '"connbytes" per-connection counter match support'
691	depends on NF_CONNTRACK
692	depends on NETFILTER_ADVANCED
693	help
694	  This option adds a `connbytes' match, which allows you to match the
695	  number of bytes and/or packets for each direction within a connection.
696
697	  If you want to compile it as a module, say M here and read
698	  <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.
699
700config NETFILTER_XT_MATCH_CONNLIMIT
701	tristate '"connlimit" match support"'
702	depends on NF_CONNTRACK
703	depends on NETFILTER_ADVANCED
704	---help---
705	  This match allows you to match against the number of parallel
706	  connections to a server per client IP address (or address block).
707
708config NETFILTER_XT_MATCH_CONNMARK
709	tristate  '"connmark" connection mark match support'
710	depends on NF_CONNTRACK
711	depends on NETFILTER_ADVANCED
712	select NETFILTER_XT_CONNMARK
713	---help---
714	This is a backwards-compat option for the user's convenience
715	(e.g. when running oldconfig). It selects
716	CONFIG_NETFILTER_XT_CONNMARK (combined connmark/CONNMARK module).
717
718config NETFILTER_XT_MATCH_CONNTRACK
719	tristate '"conntrack" connection tracking match support'
720	depends on NF_CONNTRACK
721	default m if NETFILTER_ADVANCED=n
722	help
723	  This is a general conntrack match module, a superset of the state match.
724
725	  It allows matching on additional conntrack information, which is
726	  useful in complex configurations, such as NAT gateways with multiple
727	  internet links or tunnels.
728
729	  To compile it as a module, choose M here.  If unsure, say N.
730
731config NETFILTER_XT_MATCH_CPU
732	tristate '"cpu" match support'
733	depends on NETFILTER_ADVANCED
734	help
735	  CPU matching allows you to match packets based on the CPU
736	  currently handling the packet.
737
738	  To compile it as a module, choose M here.  If unsure, say N.
739
740config NETFILTER_XT_MATCH_DCCP
741	tristate '"dccp" protocol match support'
742	depends on NETFILTER_ADVANCED
743	default IP_DCCP
744	help
745	  With this option enabled, you will be able to use the iptables
746	  `dccp' match in order to match on DCCP source/destination ports
747	  and DCCP flags.
748
749	  If you want to compile it as a module, say M here and read
750	  <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.
751
752config NETFILTER_XT_MATCH_DEVGROUP
753	tristate '"devgroup" match support'
754	depends on NETFILTER_ADVANCED
755	help
756	  This options adds a `devgroup' match, which allows to match on the
757	  device group a network device is assigned to.
758
759	  To compile it as a module, choose M here.  If unsure, say N.
760
761config NETFILTER_XT_MATCH_DSCP
762	tristate '"dscp" and "tos" match support'
763	depends on NETFILTER_ADVANCED
764	help
765	  This option adds a `DSCP' match, which allows you to match against
766	  the IPv4/IPv6 header DSCP field (differentiated services codepoint).
767
768	  The DSCP field can have any value between 0x0 and 0x3f inclusive.
769
770	  It will also add a "tos" match, which allows you to match packets
771	  based on the Type Of Service fields of the IPv4 packet (which share
772	  the same bits as DSCP).
773
774	  To compile it as a module, choose M here.  If unsure, say N.
775
776config NETFILTER_XT_MATCH_ESP
777	tristate '"esp" match support'
778	depends on NETFILTER_ADVANCED
779	help
780	  This match extension allows you to match a range of SPIs
781	  inside ESP header of IPSec packets.
782
783	  To compile it as a module, choose M here.  If unsure, say N.
784
785config NETFILTER_XT_MATCH_HASHLIMIT
786	tristate '"hashlimit" match support'
787	depends on (IP6_NF_IPTABLES || IP6_NF_IPTABLES=n)
788	depends on NETFILTER_ADVANCED
789	help
790	  This option adds a `hashlimit' match.
791
792	  As opposed to `limit', this match dynamically creates a hash table
793	  of limit buckets, based on your selection of source/destination
794	  addresses and/or ports.
795
796	  It enables you to express policies like `10kpps for any given
797	  destination address' or `500pps from any given source address'
798	  with a single rule.
799
800config NETFILTER_XT_MATCH_HELPER
801	tristate '"helper" match support'
802	depends on NF_CONNTRACK
803	depends on NETFILTER_ADVANCED
804	help
805	  Helper matching allows you to match packets in dynamic connections
806	  tracked by a conntrack-helper, ie. ip_conntrack_ftp
807
808	  To compile it as a module, choose M here.  If unsure, say Y.
809
810config NETFILTER_XT_MATCH_HL
811	tristate '"hl" hoplimit/TTL match support'
812	depends on NETFILTER_ADVANCED
813	---help---
814	HL matching allows you to match packets based on the hoplimit
815	in the IPv6 header, or the time-to-live field in the IPv4
816	header of the packet.
817
818config NETFILTER_XT_MATCH_IPRANGE
819	tristate '"iprange" address range match support'
820	depends on NETFILTER_ADVANCED
821	---help---
822	This option adds a "iprange" match, which allows you to match based on
823	an IP address range. (Normal iptables only matches on single addresses
824	with an optional mask.)
825
826	If unsure, say M.
827
828config NETFILTER_XT_MATCH_IPVS
829	tristate '"ipvs" match support'
830	depends on IP_VS
831	depends on NETFILTER_ADVANCED
832	depends on NF_CONNTRACK
833	help
834	  This option allows you to match against IPVS properties of a packet.
835
836	  If unsure, say N.
837
838config NETFILTER_XT_MATCH_LENGTH
839	tristate '"length" match support'
840	depends on NETFILTER_ADVANCED
841	help
842	  This option allows you to match the length of a packet against a
843	  specific value or range of values.
844
845	  To compile it as a module, choose M here.  If unsure, say N.
846
847config NETFILTER_XT_MATCH_LIMIT
848	tristate '"limit" match support'
849	depends on NETFILTER_ADVANCED
850	help
851	  limit matching allows you to control the rate at which a rule can be
852	  matched: mainly useful in combination with the LOG target ("LOG
853	  target support", below) and to avoid some Denial of Service attacks.
854
855	  To compile it as a module, choose M here.  If unsure, say N.
856
857config NETFILTER_XT_MATCH_MAC
858	tristate '"mac" address match support'
859	depends on NETFILTER_ADVANCED
860	help
861	  MAC matching allows you to match packets based on the source
862	  Ethernet address of the packet.
863
864	  To compile it as a module, choose M here.  If unsure, say N.
865
866config NETFILTER_XT_MATCH_MARK
867	tristate '"mark" match support'
868	depends on NETFILTER_ADVANCED
869	select NETFILTER_XT_MARK
870	---help---
871	This is a backwards-compat option for the user's convenience
872	(e.g. when running oldconfig). It selects
873	CONFIG_NETFILTER_XT_MARK (combined mark/MARK module).
874
875config NETFILTER_XT_MATCH_MULTIPORT
876	tristate '"multiport" Multiple port match support'
877	depends on NETFILTER_ADVANCED
878	help
879	  Multiport matching allows you to match TCP or UDP packets based on
880	  a series of source or destination ports: normally a rule can only
881	  match a single range of ports.
882
883	  To compile it as a module, choose M here.  If unsure, say N.
884
885config NETFILTER_XT_MATCH_OSF
886	tristate '"osf" Passive OS fingerprint match'
887	depends on NETFILTER_ADVANCED && NETFILTER_NETLINK
888	help
889	  This option selects the Passive OS Fingerprinting match module
890	  that allows to passively match the remote operating system by
891	  analyzing incoming TCP SYN packets.
892
893	  Rules and loading software can be downloaded from
894	  http://www.ioremap.net/projects/osf
895
896	  To compile it as a module, choose M here.  If unsure, say N.
897
898config NETFILTER_XT_MATCH_OWNER
899	tristate '"owner" match support'
900	depends on NETFILTER_ADVANCED
901	---help---
902	Socket owner matching allows you to match locally-generated packets
903	based on who created the socket: the user or group. It is also
904	possible to check whether a socket actually exists.
905
906config NETFILTER_XT_MATCH_POLICY
907	tristate 'IPsec "policy" match support'
908	depends on XFRM
909	default m if NETFILTER_ADVANCED=n
910	help
911	  Policy matching allows you to match packets based on the
912	  IPsec policy that was used during decapsulation/will
913	  be used during encapsulation.
914
915	  To compile it as a module, choose M here.  If unsure, say N.
916
917config NETFILTER_XT_MATCH_PHYSDEV
918	tristate '"physdev" match support'
919	depends on BRIDGE && BRIDGE_NETFILTER
920	depends on NETFILTER_ADVANCED
921	help
922	  Physdev packet matching matches against the physical bridge ports
923	  the IP packet arrived on or will leave by.
924
925	  To compile it as a module, choose M here.  If unsure, say N.
926
927config NETFILTER_XT_MATCH_PKTTYPE
928	tristate '"pkttype" packet type match support'
929	depends on NETFILTER_ADVANCED
930	help
931	  Packet type matching allows you to match a packet by
932	  its "class", eg. BROADCAST, MULTICAST, ...
933
934	  Typical usage:
935	  iptables -A INPUT -m pkttype --pkt-type broadcast -j LOG
936
937	  To compile it as a module, choose M here.  If unsure, say N.
938
939config NETFILTER_XT_MATCH_QUOTA
940	tristate '"quota" match support'
941	depends on NETFILTER_ADVANCED
942	help
943	  This option adds a `quota' match, which allows to match on a
944	  byte counter.
945
946	  If you want to compile it as a module, say M here and read
947	  <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.
948
949config NETFILTER_XT_MATCH_RATEEST
950	tristate '"rateest" match support'
951	depends on NETFILTER_ADVANCED
952	select NETFILTER_XT_TARGET_RATEEST
953	help
954	  This option adds a `rateest' match, which allows to match on the
955	  rate estimated by the RATEEST target.
956
957	  To compile it as a module, choose M here.  If unsure, say N.
958
959config NETFILTER_XT_MATCH_REALM
960	tristate  '"realm" match support'
961	depends on NETFILTER_ADVANCED
962	select IP_ROUTE_CLASSID
963	help
964	  This option adds a `realm' match, which allows you to use the realm
965	  key from the routing subsystem inside iptables.
966
967	  This match pretty much resembles the CONFIG_NET_CLS_ROUTE4 option
968	  in tc world.
969
970	  If you want to compile it as a module, say M here and read
971	  <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.
972
973config NETFILTER_XT_MATCH_RECENT
974	tristate '"recent" match support'
975	depends on NETFILTER_ADVANCED
976	---help---
977	This match is used for creating one or many lists of recently
978	used addresses and then matching against that/those list(s).
979
980	Short options are available by using 'iptables -m recent -h'
981	Official Website: <http://snowman.net/projects/ipt_recent/>
982
983config NETFILTER_XT_MATCH_SCTP
984	tristate  '"sctp" protocol match support (EXPERIMENTAL)'
985	depends on EXPERIMENTAL
986	depends on NETFILTER_ADVANCED
987	default IP_SCTP
988	help
989	  With this option enabled, you will be able to use the
990	  `sctp' match in order to match on SCTP source/destination ports
991	  and SCTP chunk types.
992
993	  If you want to compile it as a module, say M here and read
994	  <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.
995
996config NETFILTER_XT_MATCH_SOCKET
997	tristate '"socket" match support (EXPERIMENTAL)'
998	depends on EXPERIMENTAL
999	depends on NETFILTER_TPROXY
1000	depends on NETFILTER_XTABLES
1001	depends on NETFILTER_ADVANCED
1002	depends on !NF_CONNTRACK || NF_CONNTRACK
1003	select NF_DEFRAG_IPV4
1004	select NF_DEFRAG_IPV6 if IP6_NF_IPTABLES
1005	help
1006	  This option adds a `socket' match, which can be used to match
1007	  packets for which a TCP or UDP socket lookup finds a valid socket.
1008	  It can be used in combination with the MARK target and policy
1009	  routing to implement full featured non-locally bound sockets.
1010
1011	  To compile it as a module, choose M here.  If unsure, say N.
1012
1013config NETFILTER_XT_MATCH_STATE
1014	tristate '"state" match support'
1015	depends on NF_CONNTRACK
1016	default m if NETFILTER_ADVANCED=n
1017	help
1018	  Connection state matching allows you to match packets based on their
1019	  relationship to a tracked connection (ie. previous packets).  This
1020	  is a powerful tool for packet classification.
1021
1022	  To compile it as a module, choose M here.  If unsure, say N.
1023
1024config NETFILTER_XT_MATCH_STATISTIC
1025	tristate '"statistic" match support'
1026	depends on NETFILTER_ADVANCED
1027	help
1028	  This option adds a `statistic' match, which allows you to match
1029	  on packets periodically or randomly with a given percentage.
1030
1031	  To compile it as a module, choose M here.  If unsure, say N.
1032
1033config NETFILTER_XT_MATCH_STRING
1034	tristate  '"string" match support'
1035	depends on NETFILTER_ADVANCED
1036	select TEXTSEARCH
1037	select TEXTSEARCH_KMP
1038	select TEXTSEARCH_BM
1039	select TEXTSEARCH_FSM
1040	help
1041	  This option adds a `string' match, which allows you to look for
1042	  pattern matchings in packets.
1043
1044	  To compile it as a module, choose M here.  If unsure, say N.
1045
1046config NETFILTER_XT_MATCH_TCPMSS
1047	tristate '"tcpmss" match support'
1048	depends on NETFILTER_ADVANCED
1049	help
1050	  This option adds a `tcpmss' match, which allows you to examine the
1051	  MSS value of TCP SYN packets, which control the maximum packet size
1052	  for that connection.
1053
1054	  To compile it as a module, choose M here.  If unsure, say N.
1055
1056config NETFILTER_XT_MATCH_TIME
1057	tristate '"time" match support'
1058	depends on NETFILTER_ADVANCED
1059	---help---
1060	  This option adds a "time" match, which allows you to match based on
1061	  the packet arrival time (at the machine which netfilter is running)
1062	  on) or departure time/date (for locally generated packets).
1063
1064	  If you say Y here, try `iptables -m time --help` for
1065	  more information.
1066
1067	  If you want to compile it as a module, say M here.
1068	  If unsure, say N.
1069
1070config NETFILTER_XT_MATCH_U32
1071	tristate '"u32" match support'
1072	depends on NETFILTER_ADVANCED
1073	---help---
1074	  u32 allows you to extract quantities of up to 4 bytes from a packet,
1075	  AND them with specified masks, shift them by specified amounts and
1076	  test whether the results are in any of a set of specified ranges.
1077	  The specification of what to extract is general enough to skip over
1078	  headers with lengths stored in the packet, as in IP or TCP header
1079	  lengths.
1080
1081	  Details and examples are in the kernel module source.
1082
1083endif # NETFILTER_XTABLES
1084
1085endmenu
1086
1087source "net/netfilter/ipset/Kconfig"
1088
1089source "net/netfilter/ipvs/Kconfig"
1090