2 # IP netfilter configuration
5 menu "IP: Netfilter Configuration"
6 depends on INET && NETFILTER
8 config NF_CONNTRACK_IPV4
9 tristate "IPv4 support for new connection tracking (EXPERIMENTAL)"
10 depends on EXPERIMENTAL && NF_CONNTRACK
12 Connection tracking keeps a record of what packets have passed
13 through your machine, in order to figure out how they are related
16 This is IPv4 support on Layer 3 independent connection tracking.
17 Layer 3 independent connection tracking is experimental scheme
18 which generalize ip_conntrack to support other layer 3 protocols.
20 To compile it as a module, choose M here. If unsure, say N.
22 # connection tracking, helpers and protocols
23 config IP_NF_CONNTRACK
24 tristate "Connection tracking (required for masq/NAT)"
26 Connection tracking keeps a record of what packets have passed
27 through your machine, in order to figure out how they are related
30 This is required to do Masquerading or other kinds of Network
31 Address Translation (except for Fast NAT). It can also be used to
32 enhance packet filtering (see `Connection state match support'
35 To compile it as a module, choose M here. If unsure, say N.
38 bool "Connection tracking flow accounting"
39 depends on IP_NF_CONNTRACK
41 If this option is enabled, the connection tracking code will
42 keep per-flow packet and byte counters.
44 Those counters can be used for flow-based accounting or the
49 config IP_NF_CONNTRACK_MARK
50 bool 'Connection mark tracking support'
51 depends on IP_NF_CONNTRACK
53 This option enables support for connection marks, used by the
54 `CONNMARK' target and `connmark' match. Similar to the mark value
55 of packets, but this mark value is kept in the conntrack session
56 instead of the individual packets.
58 config IP_NF_CONNTRACK_SECMARK
59 bool 'Connection tracking security mark support'
60 depends on IP_NF_CONNTRACK && NETWORK_SECMARK
62 This option enables security markings to be applied to
63 connections. Typically they are copied to connections from
64 packets using the CONNSECMARK target and copied back from
65 connections to packets with the same target, with the packets
66 being originally labeled via SECMARK.
70 config IP_NF_CONNTRACK_EVENTS
71 bool "Connection tracking events (EXPERIMENTAL)"
72 depends on EXPERIMENTAL && IP_NF_CONNTRACK
74 If this option is enabled, the connection tracking code will
75 provide a notifier chain that can be used by other kernel code
76 to get notified about changes in the connection tracking state.
80 config IP_NF_CONNTRACK_NETLINK
81 tristate 'Connection tracking netlink interface (EXPERIMENTAL)'
82 depends on EXPERIMENTAL && IP_NF_CONNTRACK && NETFILTER_NETLINK
83 depends on IP_NF_CONNTRACK!=y || NETFILTER_NETLINK!=m
84 depends on IP_NF_NAT=n || IP_NF_NAT
86 This option enables support for a netlink-based userspace interface
89 config IP_NF_CT_PROTO_SCTP
90 tristate 'SCTP protocol connection tracking support (EXPERIMENTAL)'
91 depends on IP_NF_CONNTRACK && EXPERIMENTAL
93 With this option enabled, the connection tracking code will
94 be able to do state tracking on SCTP connections.
96 If you want to compile it as a module, say M here and read
97 <file:Documentation/modules.txt>. If unsure, say `N'.
100 tristate "FTP protocol support"
101 depends on IP_NF_CONNTRACK
103 Tracking FTP connections is problematic: special helpers are
104 required for tracking them, and doing masquerading and other forms
105 of Network Address Translation on them.
107 To compile it as a module, choose M here. If unsure, say Y.
110 tristate "IRC protocol support"
111 depends on IP_NF_CONNTRACK
113 There is a commonly-used extension to IRC called
114 Direct Client-to-Client Protocol (DCC). This enables users to send
115 files to each other, and also chat to each other without the need
116 of a server. DCC Sending is used anywhere you send files over IRC,
117 and DCC Chat is most commonly used by Eggdrop bots. If you are
118 using NAT, this extension will enable you to send files and initiate
119 chats. Note that you do NOT need this extension to get files or
120 have others initiate chats, or everything else in IRC.
122 To compile it as a module, choose M here. If unsure, say Y.
124 config IP_NF_NETBIOS_NS
125 tristate "NetBIOS name service protocol support (EXPERIMENTAL)"
126 depends on IP_NF_CONNTRACK && EXPERIMENTAL
128 NetBIOS name service requests are sent as broadcast messages from an
129 unprivileged port and responded to with unicast messages to the
130 same port. This make them hard to firewall properly because connection
131 tracking doesn't deal with broadcasts. This helper tracks locally
132 originating NetBIOS name service requests and the corresponding
133 responses. It relies on correct IP address configuration, specifically
134 netmask and broadcast address. When properly configured, the output
135 of "ip address show" should look similar to this:
137 $ ip -4 address show eth0
138 4: eth0: <BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 1000
139 inet 172.16.2.252/24 brd 172.16.2.255 scope global eth0
141 To compile it as a module, choose M here. If unsure, say N.
144 tristate "TFTP protocol support"
145 depends on IP_NF_CONNTRACK
147 TFTP connection tracking helper, this is required depending
148 on how restrictive your ruleset is.
149 If you are using a tftp client behind -j SNAT or -j MASQUERADING
152 To compile it as a module, choose M here. If unsure, say Y.
155 tristate "Amanda backup protocol support"
156 depends on IP_NF_CONNTRACK
158 select TEXTSEARCH_KMP
160 If you are running the Amanda backup package <http://www.amanda.org/>
161 on this machine or machines that will be MASQUERADED through this
162 machine, then you may want to enable this feature. This allows the
163 connection tracking and natting code to allow the sub-channels that
164 Amanda requires for communication of the backup data, messages and
167 To compile it as a module, choose M here. If unsure, say Y.
170 tristate 'PPTP protocol support'
171 depends on IP_NF_CONNTRACK
173 This module adds support for PPTP (Point to Point Tunnelling
174 Protocol, RFC2637) connection tracking and NAT.
176 If you are running PPTP sessions over a stateful firewall or NAT
177 box, you may want to enable this feature.
179 Please note that not all PPTP modes of operation are supported yet.
180 For more info, read top of the file
181 net/ipv4/netfilter/ip_conntrack_pptp.c
183 If you want to compile it as a module, say M here and read
184 Documentation/modules.txt. If unsure, say `N'.
187 tristate 'H.323 protocol support (EXPERIMENTAL)'
188 depends on IP_NF_CONNTRACK && EXPERIMENTAL
190 H.323 is a VoIP signalling protocol from ITU-T. As one of the most
191 important VoIP protocols, it is widely used by voice hardware and
192 software including voice gateways, IP phones, Netmeeting, OpenPhone,
195 With this module you can support H.323 on a connection tracking/NAT
198 This module supports RAS, Fast Start, H.245 Tunnelling, Call
199 Forwarding, RTP/RTCP and T.120 based audio, video, fax, chat,
200 whiteboard, file transfer, etc. For more information, please
201 visit http://nath323.sourceforge.net/.
203 If you want to compile it as a module, say 'M' here and read
204 Documentation/modules.txt. If unsure, say 'N'.
207 tristate "SIP protocol support (EXPERIMENTAL)"
208 depends on IP_NF_CONNTRACK && EXPERIMENTAL
210 SIP is an application-layer control protocol that can establish,
211 modify, and terminate multimedia sessions (conferences) such as
212 Internet telephony calls. With the ip_conntrack_sip and
213 the ip_nat_sip modules you can support the protocol on a connection
214 tracking/NATing firewall.
216 To compile it as a module, choose M here. If unsure, say Y.
219 tristate "IP Userspace queueing via NETLINK (OBSOLETE)"
221 Netfilter has the ability to queue packets to user space: the
222 netlink device can be used to access them using this driver.
224 This option enables the old IPv4-only "ip_queue" implementation
225 which has been obsoleted by the new "nfnetlink_queue" code (see
226 CONFIG_NETFILTER_NETLINK_QUEUE).
228 To compile it as a module, choose M here. If unsure, say N.
230 config IP_NF_IPTABLES
231 tristate "IP tables support (required for filtering/masq/NAT)"
232 depends on NETFILTER_XTABLES
234 iptables is a general, extensible packet identification framework.
235 The packet filtering and full NAT (masquerading, port forwarding,
236 etc) subsystems now use this: say `Y' or `M' here if you want to use
239 To compile it as a module, choose M here. If unsure, say N.
242 config IP_NF_MATCH_IPRANGE
243 tristate "IP range match support"
244 depends on IP_NF_IPTABLES
246 This option makes possible to match IP addresses against IP address
249 To compile it as a module, choose M here. If unsure, say N.
251 config IP_NF_MATCH_TOS
252 tristate "TOS match support"
253 depends on IP_NF_IPTABLES
255 TOS matching allows you to match packets based on the Type Of
256 Service fields of the IP packet.
258 To compile it as a module, choose M here. If unsure, say N.
260 config IP_NF_MATCH_RECENT
261 tristate "recent match support"
262 depends on IP_NF_IPTABLES
264 This match is used for creating one or many lists of recently
265 used addresses and then matching against that/those list(s).
267 Short options are available by using 'iptables -m recent -h'
268 Official Website: <http://snowman.net/projects/ipt_recent/>
270 To compile it as a module, choose M here. If unsure, say N.
272 config IP_NF_MATCH_ECN
273 tristate "ECN match support"
274 depends on IP_NF_IPTABLES
276 This option adds a `ECN' match, which allows you to match against
277 the IPv4 and TCP header ECN fields.
279 To compile it as a module, choose M here. If unsure, say N.
281 config IP_NF_MATCH_AH
282 tristate "AH match support"
283 depends on IP_NF_IPTABLES
285 This match extension allows you to match a range of SPIs
286 inside AH header of IPSec packets.
288 To compile it as a module, choose M here. If unsure, say N.
290 config IP_NF_MATCH_TTL
291 tristate "TTL match support"
292 depends on IP_NF_IPTABLES
294 This adds CONFIG_IP_NF_MATCH_TTL option, which enabled the user
295 to match packets by their TTL value.
297 To compile it as a module, choose M here. If unsure, say N.
299 config IP_NF_MATCH_OWNER
300 tristate "Owner match support"
301 depends on IP_NF_IPTABLES
303 Packet owner matching allows you to match locally-generated packets
304 based on who created them: the user, group, process or session.
306 To compile it as a module, choose M here. If unsure, say N.
308 config IP_NF_MATCH_ADDRTYPE
309 tristate 'address type match support'
310 depends on IP_NF_IPTABLES
312 This option allows you to match what routing thinks of an address,
313 eg. UNICAST, LOCAL, BROADCAST, ...
315 If you want to compile it as a module, say M here and read
316 <file:Documentation/modules.txt>. If unsure, say `N'.
318 config IP_NF_MATCH_HASHLIMIT
319 tristate 'hashlimit match support'
320 depends on IP_NF_IPTABLES
322 This option adds a new iptables `hashlimit' match.
324 As opposed to `limit', this match dynamically creates a hash table
325 of limit buckets, based on your selection of source/destination
326 ip addresses and/or ports.
328 It enables you to express policies like `10kpps for any given
329 destination IP' or `500pps from any given source IP' with a single
332 # `filter', generic and specific targets
334 tristate "Packet filtering"
335 depends on IP_NF_IPTABLES
337 Packet filtering defines a table `filter', which has a series of
338 rules for simple packet filtering at local input, forwarding and
339 local output. See the man page for iptables(8).
341 To compile it as a module, choose M here. If unsure, say N.
343 config IP_NF_TARGET_REJECT
344 tristate "REJECT target support"
345 depends on IP_NF_FILTER
347 The REJECT target allows a filtering rule to specify that an ICMP
348 error should be issued in response to an incoming packet, rather
349 than silently being dropped.
351 To compile it as a module, choose M here. If unsure, say N.
353 config IP_NF_TARGET_LOG
354 tristate "LOG target support"
355 depends on IP_NF_IPTABLES
357 This option adds a `LOG' target, which allows you to create rules in
358 any iptables table which records the packet header to the syslog.
360 To compile it as a module, choose M here. If unsure, say N.
362 config IP_NF_TARGET_ULOG
363 tristate "ULOG target support"
364 depends on IP_NF_IPTABLES
367 This option enables the old IPv4-only "ipt_ULOG" implementation
368 which has been obsoleted by the new "nfnetlink_log" code (see
369 CONFIG_NETFILTER_NETLINK_LOG).
371 This option adds a `ULOG' target, which allows you to create rules in
372 any iptables table. The packet is passed to a userspace logging
373 daemon using netlink multicast sockets; unlike the LOG target
374 which can only be viewed through syslog.
376 The apropriate userspace logging daemon (ulogd) may be obtained from
377 <http://www.gnumonks.org/projects/ulogd/>
379 To compile it as a module, choose M here. If unsure, say N.
381 config IP_NF_TARGET_TCPMSS
382 tristate "TCPMSS target support"
383 depends on IP_NF_IPTABLES
385 This option adds a `TCPMSS' target, which allows you to alter the
386 MSS value of TCP SYN packets, to control the maximum size for that
387 connection (usually limiting it to your outgoing interface's MTU
390 This is used to overcome criminally braindead ISPs or servers which
391 block ICMP Fragmentation Needed packets. The symptoms of this
392 problem are that everything works fine from your Linux
393 firewall/router, but machines behind it can never exchange large
395 1) Web browsers connect, then hang with no data received.
396 2) Small mail works fine, but large emails hang.
397 3) ssh works fine, but scp hangs after initial handshaking.
399 Workaround: activate this option and add a rule to your firewall
402 iptables -A FORWARD -p tcp --tcp-flags SYN,RST SYN \
403 -j TCPMSS --clamp-mss-to-pmtu
405 To compile it as a module, choose M here. If unsure, say N.
407 # NAT + specific targets
410 depends on IP_NF_IPTABLES && IP_NF_CONNTRACK
412 The Full NAT option allows masquerading, port forwarding and other
413 forms of full Network Address Port Translation. It is controlled by
414 the `nat' table in iptables: see the man page for iptables(8).
416 To compile it as a module, choose M here. If unsure, say N.
418 config IP_NF_NAT_NEEDED
420 depends on IP_NF_NAT != n
423 config IP_NF_TARGET_MASQUERADE
424 tristate "MASQUERADE target support"
427 Masquerading is a special case of NAT: all outgoing connections are
428 changed to seem to come from a particular interface's address, and
429 if the interface goes down, those connections are lost. This is
430 only useful for dialup accounts with dynamic IP address (ie. your IP
431 address will be different on next dialup).
433 To compile it as a module, choose M here. If unsure, say N.
435 config IP_NF_TARGET_REDIRECT
436 tristate "REDIRECT target support"
439 REDIRECT is a special case of NAT: all incoming connections are
440 mapped onto the incoming interface's address, causing the packets to
441 come to the local machine instead of passing through. This is
442 useful for transparent proxies.
444 To compile it as a module, choose M here. If unsure, say N.
446 config IP_NF_TARGET_NETMAP
447 tristate "NETMAP target support"
450 NETMAP is an implementation of static 1:1 NAT mapping of network
451 addresses. It maps the network address part, while keeping the host
452 address part intact. It is similar to Fast NAT, except that
453 Netfilter's connection tracking doesn't work well with Fast NAT.
455 To compile it as a module, choose M here. If unsure, say N.
457 config IP_NF_TARGET_SAME
458 tristate "SAME target support"
461 This option adds a `SAME' target, which works like the standard SNAT
462 target, but attempts to give clients the same IP for all connections.
464 To compile it as a module, choose M here. If unsure, say N.
466 config IP_NF_NAT_SNMP_BASIC
467 tristate "Basic SNMP-ALG support (EXPERIMENTAL)"
468 depends on EXPERIMENTAL && IP_NF_NAT
471 This module implements an Application Layer Gateway (ALG) for
472 SNMP payloads. In conjunction with NAT, it allows a network
473 management system to access multiple private networks with
474 conflicting addresses. It works by modifying IP addresses
475 inside SNMP payloads to match IP-layer NAT mapping.
477 This is the "basic" form of SNMP-ALG, as described in RFC 2962
479 To compile it as a module, choose M here. If unsure, say N.
483 depends on IP_NF_IPTABLES!=n && IP_NF_CONNTRACK!=n && IP_NF_NAT!=n
484 default IP_NF_NAT if IP_NF_IRC=y
485 default m if IP_NF_IRC=m
487 # If they want FTP, set to $CONFIG_IP_NF_NAT (m or y),
488 # or $CONFIG_IP_NF_FTP (m or y), whichever is weaker. Argh.
491 depends on IP_NF_IPTABLES!=n && IP_NF_CONNTRACK!=n && IP_NF_NAT!=n
492 default IP_NF_NAT if IP_NF_FTP=y
493 default m if IP_NF_FTP=m
495 config IP_NF_NAT_TFTP
497 depends on IP_NF_IPTABLES!=n && IP_NF_CONNTRACK!=n && IP_NF_NAT!=n
498 default IP_NF_NAT if IP_NF_TFTP=y
499 default m if IP_NF_TFTP=m
501 config IP_NF_NAT_AMANDA
503 depends on IP_NF_IPTABLES!=n && IP_NF_CONNTRACK!=n && IP_NF_NAT!=n
504 default IP_NF_NAT if IP_NF_AMANDA=y
505 default m if IP_NF_AMANDA=m
507 config IP_NF_NAT_PPTP
509 depends on IP_NF_NAT!=n && IP_NF_PPTP!=n
510 default IP_NF_NAT if IP_NF_PPTP=y
511 default m if IP_NF_PPTP=m
513 config IP_NF_NAT_H323
515 depends on IP_NF_IPTABLES!=n && IP_NF_CONNTRACK!=n && IP_NF_NAT!=n
516 default IP_NF_NAT if IP_NF_H323=y
517 default m if IP_NF_H323=m
521 depends on IP_NF_IPTABLES!=n && IP_NF_CONNTRACK!=n && IP_NF_NAT!=n
522 default IP_NF_NAT if IP_NF_SIP=y
523 default m if IP_NF_SIP=m
525 # mangle + specific targets
527 tristate "Packet mangling"
528 depends on IP_NF_IPTABLES
530 This option adds a `mangle' table to iptables: see the man page for
531 iptables(8). This table is used for various packet alterations
532 which can effect how the packet is routed.
534 To compile it as a module, choose M here. If unsure, say N.
536 config IP_NF_TARGET_TOS
537 tristate "TOS target support"
538 depends on IP_NF_MANGLE
540 This option adds a `TOS' target, which allows you to create rules in
541 the `mangle' table which alter the Type Of Service field of an IP
542 packet prior to routing.
544 To compile it as a module, choose M here. If unsure, say N.
546 config IP_NF_TARGET_ECN
547 tristate "ECN target support"
548 depends on IP_NF_MANGLE
550 This option adds a `ECN' target, which can be used in the iptables mangle
553 You can use this target to remove the ECN bits from the IPv4 header of
554 an IP packet. This is particularly useful, if you need to work around
555 existing ECN blackholes on the internet, but don't want to disable
556 ECN support in general.
558 To compile it as a module, choose M here. If unsure, say N.
560 config IP_NF_TARGET_TTL
561 tristate 'TTL target support'
562 depends on IP_NF_MANGLE
564 This option adds a `TTL' target, which enables the user to modify
565 the TTL value of the IP header.
567 While it is safe to decrement/lower the TTL, this target also enables
568 functionality to increment and set the TTL value of the IP header to
569 arbitrary values. This is EXTREMELY DANGEROUS since you can easily
570 create immortal packets that loop forever on the network.
572 To compile it as a module, choose M here. If unsure, say N.
574 config IP_NF_TARGET_CLUSTERIP
575 tristate "CLUSTERIP target support (EXPERIMENTAL)"
576 depends on IP_NF_MANGLE && EXPERIMENTAL
577 depends on (IP_NF_CONNTRACK && IP_NF_CONNTRACK_MARK) || (NF_CONNTRACK_MARK && NF_CONNTRACK_IPV4)
579 The CLUSTERIP target allows you to build load-balancing clusters of
580 network servers without having a dedicated load-balancing
581 router/server/switch.
583 To compile it as a module, choose M here. If unsure, say N.
585 # raw + specific targets
587 tristate 'raw table support (required for NOTRACK/TRACE)'
588 depends on IP_NF_IPTABLES
590 This option adds a `raw' table to iptables. This table is the very
591 first in the netfilter framework and hooks in at the PREROUTING
594 If you want to compile it as a module, say M here and read
595 <file:Documentation/modules.txt>. If unsure, say `N'.
598 config IP_NF_ARPTABLES
599 tristate "ARP tables support"
600 depends on NETFILTER_XTABLES
602 arptables is a general, extensible packet identification framework.
603 The ARP packet filtering and mangling (manipulation)subsystems
604 use this: say Y or M here if you want to use either of those.
606 To compile it as a module, choose M here. If unsure, say N.
608 config IP_NF_ARPFILTER
609 tristate "ARP packet filtering"
610 depends on IP_NF_ARPTABLES
612 ARP packet filtering defines a table `filter', which has a series of
613 rules for simple ARP packet filtering at local input and
614 local output. On a bridge, you can also specify filtering rules
615 for forwarded ARP packets. See the man page for arptables(8).
617 To compile it as a module, choose M here. If unsure, say N.
619 config IP_NF_ARP_MANGLE
620 tristate "ARP payload mangling"
621 depends on IP_NF_ARPTABLES
623 Allows altering the ARP packet payload: source and destination
624 hardware and network addresses.