Kconfig 35 KB

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