1 menu "Core Netfilter Configuration"
2 depends on NET && INET && NETFILTER
4 config NETFILTER_NETLINK
5 tristate "Netfilter netlink interface"
7 If this option is enabled, the kernel will include support
8 for the new netfilter netlink interface.
10 config NETFILTER_NETLINK_QUEUE
11 tristate "Netfilter NFQUEUE over NFNETLINK interface"
12 depends on NETFILTER_NETLINK
14 If this option is enabled, the kernel will include support
15 for queueing packets via NFNETLINK.
17 config NETFILTER_NETLINK_LOG
18 tristate "Netfilter LOG over NFNETLINK interface"
19 depends on NETFILTER_NETLINK
21 If this option is enabled, the kernel will include support
22 for logging packets via NFNETLINK.
24 This obsoletes the existing ipt_ULOG and ebg_ulog mechanisms,
25 and is also scheduled to replace the old syslog-based ipt_LOG
28 # Rename this to NF_CONNTRACK in a 2.6.25
29 config NF_CONNTRACK_ENABLED
30 tristate "Netfilter connection tracking support"
32 Connection tracking keeps a record of what packets have passed
33 through your machine, in order to figure out how they are related
36 This is required to do Masquerading or other kinds of Network
37 Address Translation (except for Fast NAT). It can also be used to
38 enhance packet filtering (see `Connection state match support'
41 To compile it as a module, choose M here. If unsure, say N.
45 default NF_CONNTRACK_ENABLED
48 bool "Connection tracking flow accounting"
49 depends on NF_CONNTRACK
51 If this option is enabled, the connection tracking code will
52 keep per-flow packet and byte counters.
54 Those counters can be used for flow-based accounting or the
59 config NF_CONNTRACK_MARK
60 bool 'Connection mark tracking support'
61 depends on NF_CONNTRACK
63 This option enables support for connection marks, used by the
64 `CONNMARK' target and `connmark' match. Similar to the mark value
65 of packets, but this mark value is kept in the conntrack session
66 instead of the individual packets.
68 config NF_CONNTRACK_SECMARK
69 bool 'Connection tracking security mark support'
70 depends on NF_CONNTRACK && NETWORK_SECMARK
72 This option enables security markings to be applied to
73 connections. Typically they are copied to connections from
74 packets using the CONNSECMARK target and copied back from
75 connections to packets with the same target, with the packets
76 being originally labeled via SECMARK.
80 config NF_CONNTRACK_EVENTS
81 bool "Connection tracking events (EXPERIMENTAL)"
82 depends on EXPERIMENTAL && NF_CONNTRACK
84 If this option is enabled, the connection tracking code will
85 provide a notifier chain that can be used by other kernel code
86 to get notified about changes in the connection tracking state.
90 config NF_CT_PROTO_GRE
92 depends on NF_CONNTRACK
94 config NF_CT_PROTO_SCTP
95 tristate 'SCTP protocol connection tracking support (EXPERIMENTAL)'
96 depends on EXPERIMENTAL && NF_CONNTRACK
99 With this option enabled, the layer 3 independent connection
100 tracking code will be able to do state tracking on SCTP connections.
102 If you want to compile it as a module, say M here and read
103 <file:Documentation/kbuild/modules.txt>. If unsure, say `N'.
105 config NF_CT_PROTO_UDPLITE
106 tristate 'UDP-Lite protocol connection tracking support (EXPERIMENTAL)'
107 depends on EXPERIMENTAL && NF_CONNTRACK
109 With this option enabled, the layer 3 independent connection
110 tracking code will be able to do state tracking on UDP-Lite
113 To compile it as a module, choose M here. If unsure, say N.
115 config NF_CONNTRACK_AMANDA
116 tristate "Amanda backup protocol support"
117 depends on NF_CONNTRACK
119 select TEXTSEARCH_KMP
121 If you are running the Amanda backup package <http://www.amanda.org/>
122 on this machine or machines that will be MASQUERADED through this
123 machine, then you may want to enable this feature. This allows the
124 connection tracking and natting code to allow the sub-channels that
125 Amanda requires for communication of the backup data, messages and
128 To compile it as a module, choose M here. If unsure, say N.
130 config NF_CONNTRACK_FTP
131 tristate "FTP protocol support"
132 depends on NF_CONNTRACK
134 Tracking FTP connections is problematic: special helpers are
135 required for tracking them, and doing masquerading and other forms
136 of Network Address Translation on them.
138 This is FTP support on Layer 3 independent connection tracking.
139 Layer 3 independent connection tracking is experimental scheme
140 which generalize ip_conntrack to support other layer 3 protocols.
142 To compile it as a module, choose M here. If unsure, say N.
144 config NF_CONNTRACK_H323
145 tristate "H.323 protocol support (EXPERIMENTAL)"
146 depends on EXPERIMENTAL && NF_CONNTRACK && (IPV6 || IPV6=n)
148 H.323 is a VoIP signalling protocol from ITU-T. As one of the most
149 important VoIP protocols, it is widely used by voice hardware and
150 software including voice gateways, IP phones, Netmeeting, OpenPhone,
153 With this module you can support H.323 on a connection tracking/NAT
156 This module supports RAS, Fast Start, H.245 Tunnelling, Call
157 Forwarding, RTP/RTCP and T.120 based audio, video, fax, chat,
158 whiteboard, file transfer, etc. For more information, please
159 visit http://nath323.sourceforge.net/.
161 To compile it as a module, choose M here. If unsure, say N.
163 config NF_CONNTRACK_IRC
164 tristate "IRC protocol support"
165 depends on NF_CONNTRACK
167 There is a commonly-used extension to IRC called
168 Direct Client-to-Client Protocol (DCC). This enables users to send
169 files to each other, and also chat to each other without the need
170 of a server. DCC Sending is used anywhere you send files over IRC,
171 and DCC Chat is most commonly used by Eggdrop bots. If you are
172 using NAT, this extension will enable you to send files and initiate
173 chats. Note that you do NOT need this extension to get files or
174 have others initiate chats, or everything else in IRC.
176 To compile it as a module, choose M here. If unsure, say N.
178 config NF_CONNTRACK_NETBIOS_NS
179 tristate "NetBIOS name service protocol support (EXPERIMENTAL)"
180 depends on EXPERIMENTAL && NF_CONNTRACK
182 NetBIOS name service requests are sent as broadcast messages from an
183 unprivileged port and responded to with unicast messages to the
184 same port. This make them hard to firewall properly because connection
185 tracking doesn't deal with broadcasts. This helper tracks locally
186 originating NetBIOS name service requests and the corresponding
187 responses. It relies on correct IP address configuration, specifically
188 netmask and broadcast address. When properly configured, the output
189 of "ip address show" should look similar to this:
191 $ ip -4 address show eth0
192 4: eth0: <BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 1000
193 inet 172.16.2.252/24 brd 172.16.2.255 scope global eth0
195 To compile it as a module, choose M here. If unsure, say N.
197 config NF_CONNTRACK_PPTP
198 tristate "PPtP protocol support"
199 depends on NF_CONNTRACK
200 select NF_CT_PROTO_GRE
202 This module adds support for PPTP (Point to Point Tunnelling
203 Protocol, RFC2637) connection tracking and NAT.
205 If you are running PPTP sessions over a stateful firewall or NAT
206 box, you may want to enable this feature.
208 Please note that not all PPTP modes of operation are supported yet.
209 Specifically these limitations exist:
210 - Blindly assumes that control connections are always established
211 in PNS->PAC direction. This is a violation of RFC2637.
212 - Only supports a single call within each session
214 To compile it as a module, choose M here. If unsure, say N.
216 config NF_CONNTRACK_SANE
217 tristate "SANE protocol support (EXPERIMENTAL)"
218 depends on EXPERIMENTAL && NF_CONNTRACK
220 SANE is a protocol for remote access to scanners as implemented
221 by the 'saned' daemon. Like FTP, it uses separate control and
224 With this module you can support SANE on a connection tracking
227 To compile it as a module, choose M here. If unsure, say N.
229 config NF_CONNTRACK_SIP
230 tristate "SIP protocol support (EXPERIMENTAL)"
231 depends on EXPERIMENTAL && NF_CONNTRACK
233 SIP is an application-layer control protocol that can establish,
234 modify, and terminate multimedia sessions (conferences) such as
235 Internet telephony calls. With the ip_conntrack_sip and
236 the nf_nat_sip modules you can support the protocol on a connection
237 tracking/NATing firewall.
239 To compile it as a module, choose M here. If unsure, say N.
241 config NF_CONNTRACK_TFTP
242 tristate "TFTP protocol support"
243 depends on NF_CONNTRACK
245 TFTP connection tracking helper, this is required depending
246 on how restrictive your ruleset is.
247 If you are using a tftp client behind -j SNAT or -j MASQUERADING
250 To compile it as a module, choose M here. If unsure, say N.
253 tristate 'Connection tracking netlink interface (EXPERIMENTAL)'
254 depends on EXPERIMENTAL && NF_CONNTRACK && NETFILTER_NETLINK
255 depends on NF_CONNTRACK!=y || NETFILTER_NETLINK!=m
256 depends on NF_NAT=n || NF_NAT
258 This option enables support for a netlink-based userspace interface
260 config NETFILTER_XTABLES
261 tristate "Netfilter Xtables support (required for ip_tables)"
263 This is required if you intend to use any of ip_tables,
264 ip6_tables or arp_tables.
266 # alphabetically ordered list of targets
268 config NETFILTER_XT_TARGET_CLASSIFY
269 tristate '"CLASSIFY" target support'
270 depends on NETFILTER_XTABLES
272 This option adds a `CLASSIFY' target, which enables the user to set
273 the priority of a packet. Some qdiscs can use this value for
274 classification, among these are:
276 atm, cbq, dsmark, pfifo_fast, htb, prio
278 To compile it as a module, choose M here. If unsure, say N.
280 config NETFILTER_XT_TARGET_CONNMARK
281 tristate '"CONNMARK" target support'
282 depends on NETFILTER_XTABLES
283 depends on IP_NF_MANGLE || IP6_NF_MANGLE
284 depends on NF_CONNTRACK
285 select NF_CONNTRACK_MARK
287 This option adds a `CONNMARK' target, which allows one to manipulate
288 the connection mark value. Similar to the MARK target, but
289 affects the connection mark value rather than the packet mark value.
291 If you want to compile it as a module, say M here and read
292 <file:Documentation/kbuild/modules.txt>. The module will be called
293 ipt_CONNMARK.ko. If unsure, say `N'.
295 config NETFILTER_XT_TARGET_DSCP
296 tristate '"DSCP" target support'
297 depends on NETFILTER_XTABLES
298 depends on IP_NF_MANGLE || IP6_NF_MANGLE
300 This option adds a `DSCP' target, which allows you to manipulate
301 the IPv4/IPv6 header DSCP field (differentiated services codepoint).
303 The DSCP field can have any value between 0x0 and 0x3f inclusive.
305 To compile it as a module, choose M here. If unsure, say N.
307 config NETFILTER_XT_TARGET_MARK
308 tristate '"MARK" target support'
309 depends on NETFILTER_XTABLES
311 This option adds a `MARK' target, which allows you to create rules
312 in the `mangle' table which alter the netfilter mark (nfmark) field
313 associated with the packet prior to routing. This can change
314 the routing method (see `Use netfilter MARK value as routing
315 key') and can also be used by other subsystems to change their
318 To compile it as a module, choose M here. If unsure, say N.
320 config NETFILTER_XT_TARGET_NFQUEUE
321 tristate '"NFQUEUE" target Support'
322 depends on NETFILTER_XTABLES
324 This target replaced the old obsolete QUEUE target.
326 As opposed to QUEUE, it supports 65535 different queues,
329 To compile it as a module, choose M here. If unsure, say N.
331 config NETFILTER_XT_TARGET_NFLOG
332 tristate '"NFLOG" target support'
333 depends on NETFILTER_XTABLES
335 This option enables the NFLOG target, which allows to LOG
336 messages through the netfilter logging API, which can use
337 either the old LOG target, the old ULOG target or nfnetlink_log
340 To compile it as a module, choose M here. If unsure, say N.
342 config NETFILTER_XT_TARGET_NOTRACK
343 tristate '"NOTRACK" target support'
344 depends on NETFILTER_XTABLES
345 depends on IP_NF_RAW || IP6_NF_RAW
346 depends on NF_CONNTRACK
348 The NOTRACK target allows a select rule to specify
349 which packets *not* to enter the conntrack/NAT
350 subsystem with all the consequences (no ICMP error tracking,
351 no protocol helpers for the selected packets).
353 If you want to compile it as a module, say M here and read
354 <file:Documentation/kbuild/modules.txt>. If unsure, say `N'.
356 config NETFILTER_XT_TARGET_TRACE
357 tristate '"TRACE" target support'
358 depends on NETFILTER_XTABLES
359 depends on IP_NF_RAW || IP6_NF_RAW
361 The TRACE target allows you to mark packets so that the kernel
362 will log every rule which match the packets as those traverse
363 the tables, chains, rules.
365 If you want to compile it as a module, say M here and read
366 <file:Documentation/kbuild/modules.txt>. If unsure, say `N'.
368 config NETFILTER_XT_TARGET_SECMARK
369 tristate '"SECMARK" target support'
370 depends on NETFILTER_XTABLES && NETWORK_SECMARK
372 The SECMARK target allows security marking of network
373 packets, for use with security subsystems.
375 To compile it as a module, choose M here. If unsure, say N.
377 config NETFILTER_XT_TARGET_CONNSECMARK
378 tristate '"CONNSECMARK" target support'
379 depends on NETFILTER_XTABLES && NF_CONNTRACK && NF_CONNTRACK_SECMARK
381 The CONNSECMARK target copies security markings from packets
382 to connections, and restores security markings from connections
383 to packets (if the packets are not already marked). This would
384 normally be used in conjunction with the SECMARK target.
386 To compile it as a module, choose M here. If unsure, say N.
388 config NETFILTER_XT_TARGET_TCPMSS
389 tristate '"TCPMSS" target support'
390 depends on NETFILTER_XTABLES && (IPV6 || IPV6=n)
392 This option adds a `TCPMSS' target, which allows you to alter the
393 MSS value of TCP SYN packets, to control the maximum size for that
394 connection (usually limiting it to your outgoing interface's MTU
397 This is used to overcome criminally braindead ISPs or servers which
398 block ICMP Fragmentation Needed packets. The symptoms of this
399 problem are that everything works fine from your Linux
400 firewall/router, but machines behind it can never exchange large
402 1) Web browsers connect, then hang with no data received.
403 2) Small mail works fine, but large emails hang.
404 3) ssh works fine, but scp hangs after initial handshaking.
406 Workaround: activate this option and add a rule to your firewall
409 iptables -A FORWARD -p tcp --tcp-flags SYN,RST SYN \
410 -j TCPMSS --clamp-mss-to-pmtu
412 To compile it as a module, choose M here. If unsure, say N.
414 config NETFILTER_XT_TARGET_TCPOPTSTRIP
415 tristate '"TCPOPTSTRIP" target support (EXPERIMENTAL)'
416 depends on EXPERIMENTAL && NETFILTER_XTABLES
417 depends on IP_NF_MANGLE || IP6_NF_MANGLE
419 This option adds a "TCPOPTSTRIP" target, which allows you to strip
420 TCP options from TCP packets.
422 config NETFILTER_XT_MATCH_COMMENT
423 tristate '"comment" match support'
424 depends on NETFILTER_XTABLES
426 This option adds a `comment' dummy-match, which allows you to put
427 comments in your iptables ruleset.
429 If you want to compile it as a module, say M here and read
430 <file:Documentation/kbuild/modules.txt>. If unsure, say `N'.
432 config NETFILTER_XT_MATCH_CONNBYTES
433 tristate '"connbytes" per-connection counter match support'
434 depends on NETFILTER_XTABLES
435 depends on NF_CONNTRACK
438 This option adds a `connbytes' match, which allows you to match the
439 number of bytes and/or packets for each direction within a connection.
441 If you want to compile it as a module, say M here and read
442 <file:Documentation/kbuild/modules.txt>. If unsure, say `N'.
444 config NETFILTER_XT_MATCH_CONNLIMIT
445 tristate '"connlimit" match support"'
446 depends on NETFILTER_XTABLES
447 depends on NF_CONNTRACK
449 This match allows you to match against the number of parallel
450 connections to a server per client IP address (or address block).
452 config NETFILTER_XT_MATCH_CONNMARK
453 tristate '"connmark" connection mark match support'
454 depends on NETFILTER_XTABLES
455 depends on NF_CONNTRACK
456 select NF_CONNTRACK_MARK
458 This option adds a `connmark' match, which allows you to match the
459 connection mark value previously set for the session by `CONNMARK'.
461 If you want to compile it as a module, say M here and read
462 <file:Documentation/kbuild/modules.txt>. The module will be called
463 ipt_connmark.ko. If unsure, say `N'.
465 config NETFILTER_XT_MATCH_CONNTRACK
466 tristate '"conntrack" connection tracking match support'
467 depends on NETFILTER_XTABLES
468 depends on NF_CONNTRACK
470 This is a general conntrack match module, a superset of the state match.
472 It allows matching on additional conntrack information, which is
473 useful in complex configurations, such as NAT gateways with multiple
474 internet links or tunnels.
476 To compile it as a module, choose M here. If unsure, say N.
478 config NETFILTER_XT_MATCH_DCCP
479 tristate '"dccp" protocol match support'
480 depends on NETFILTER_XTABLES
482 With this option enabled, you will be able to use the iptables
483 `dccp' match in order to match on DCCP source/destination ports
486 If you want to compile it as a module, say M here and read
487 <file:Documentation/kbuild/modules.txt>. If unsure, say `N'.
489 config NETFILTER_XT_MATCH_DSCP
490 tristate '"dscp" and "tos" match support'
491 depends on NETFILTER_XTABLES
493 This option adds a `DSCP' match, which allows you to match against
494 the IPv4/IPv6 header DSCP field (differentiated services codepoint).
496 The DSCP field can have any value between 0x0 and 0x3f inclusive.
498 It will also add a "tos" match, which allows you to match packets
499 based on the Type Of Service fields of the IPv4 packet (which share
500 the same bits as DSCP).
502 To compile it as a module, choose M here. If unsure, say N.
504 config NETFILTER_XT_MATCH_ESP
505 tristate '"esp" match support'
506 depends on NETFILTER_XTABLES
508 This match extension allows you to match a range of SPIs
509 inside ESP header of IPSec packets.
511 To compile it as a module, choose M here. If unsure, say N.
513 config NETFILTER_XT_MATCH_HELPER
514 tristate '"helper" match support'
515 depends on NETFILTER_XTABLES
516 depends on NF_CONNTRACK
518 Helper matching allows you to match packets in dynamic connections
519 tracked by a conntrack-helper, ie. ip_conntrack_ftp
521 To compile it as a module, choose M here. If unsure, say Y.
523 config NETFILTER_XT_MATCH_LENGTH
524 tristate '"length" match support'
525 depends on NETFILTER_XTABLES
527 This option allows you to match the length of a packet against a
528 specific value or range of values.
530 To compile it as a module, choose M here. If unsure, say N.
532 config NETFILTER_XT_MATCH_LIMIT
533 tristate '"limit" match support'
534 depends on NETFILTER_XTABLES
536 limit matching allows you to control the rate at which a rule can be
537 matched: mainly useful in combination with the LOG target ("LOG
538 target support", below) and to avoid some Denial of Service attacks.
540 To compile it as a module, choose M here. If unsure, say N.
542 config NETFILTER_XT_MATCH_MAC
543 tristate '"mac" address match support'
544 depends on NETFILTER_XTABLES
546 MAC matching allows you to match packets based on the source
547 Ethernet address of the packet.
549 To compile it as a module, choose M here. If unsure, say N.
551 config NETFILTER_XT_MATCH_MARK
552 tristate '"mark" match support'
553 depends on NETFILTER_XTABLES
555 Netfilter mark matching allows you to match packets based on the
556 `nfmark' value in the packet. This can be set by the MARK target
559 To compile it as a module, choose M here. If unsure, say N.
561 config NETFILTER_XT_MATCH_OWNER
562 tristate '"owner" match support'
563 depends on NETFILTER_XTABLES
565 Socket owner matching allows you to match locally-generated packets
566 based on who created the socket: the user or group. It is also
567 possible to check whether a socket actually exists.
569 config NETFILTER_XT_MATCH_POLICY
570 tristate 'IPsec "policy" match support'
571 depends on NETFILTER_XTABLES && XFRM
573 Policy matching allows you to match packets based on the
574 IPsec policy that was used during decapsulation/will
575 be used during encapsulation.
577 To compile it as a module, choose M here. If unsure, say N.
579 config NETFILTER_XT_MATCH_MULTIPORT
580 tristate '"multiport" Multiple port match support'
581 depends on NETFILTER_XTABLES
583 Multiport matching allows you to match TCP or UDP packets based on
584 a series of source or destination ports: normally a rule can only
585 match a single range of ports.
587 To compile it as a module, choose M here. If unsure, say N.
589 config NETFILTER_XT_MATCH_PHYSDEV
590 tristate '"physdev" match support'
591 depends on NETFILTER_XTABLES && BRIDGE && BRIDGE_NETFILTER
593 Physdev packet matching matches against the physical bridge ports
594 the IP packet arrived on or will leave by.
596 To compile it as a module, choose M here. If unsure, say N.
598 config NETFILTER_XT_MATCH_PKTTYPE
599 tristate '"pkttype" packet type match support'
600 depends on NETFILTER_XTABLES
602 Packet type matching allows you to match a packet by
603 its "class", eg. BROADCAST, MULTICAST, ...
606 iptables -A INPUT -m pkttype --pkt-type broadcast -j LOG
608 To compile it as a module, choose M here. If unsure, say N.
610 config NETFILTER_XT_MATCH_QUOTA
611 tristate '"quota" match support'
612 depends on NETFILTER_XTABLES
614 This option adds a `quota' match, which allows to match on a
617 If you want to compile it as a module, say M here and read
618 <file:Documentation/kbuild/modules.txt>. If unsure, say `N'.
620 config NETFILTER_XT_MATCH_REALM
621 tristate '"realm" match support'
622 depends on NETFILTER_XTABLES
625 This option adds a `realm' match, which allows you to use the realm
626 key from the routing subsystem inside iptables.
628 This match pretty much resembles the CONFIG_NET_CLS_ROUTE4 option
631 If you want to compile it as a module, say M here and read
632 <file:Documentation/kbuild/modules.txt>. If unsure, say `N'.
634 config NETFILTER_XT_MATCH_SCTP
635 tristate '"sctp" protocol match support (EXPERIMENTAL)'
636 depends on NETFILTER_XTABLES && EXPERIMENTAL
638 With this option enabled, you will be able to use the
639 `sctp' match in order to match on SCTP source/destination ports
640 and SCTP chunk types.
642 If you want to compile it as a module, say M here and read
643 <file:Documentation/kbuild/modules.txt>. If unsure, say `N'.
645 config NETFILTER_XT_MATCH_STATE
646 tristate '"state" match support'
647 depends on NETFILTER_XTABLES
648 depends on NF_CONNTRACK
650 Connection state matching allows you to match packets based on their
651 relationship to a tracked connection (ie. previous packets). This
652 is a powerful tool for packet classification.
654 To compile it as a module, choose M here. If unsure, say N.
656 config NETFILTER_XT_MATCH_STATISTIC
657 tristate '"statistic" match support'
658 depends on NETFILTER_XTABLES
660 This option adds a `statistic' match, which allows you to match
661 on packets periodically or randomly with a given percentage.
663 To compile it as a module, choose M here. If unsure, say N.
665 config NETFILTER_XT_MATCH_STRING
666 tristate '"string" match support'
667 depends on NETFILTER_XTABLES
669 select TEXTSEARCH_KMP
671 select TEXTSEARCH_FSM
673 This option adds a `string' match, which allows you to look for
674 pattern matchings in packets.
676 To compile it as a module, choose M here. If unsure, say N.
678 config NETFILTER_XT_MATCH_TCPMSS
679 tristate '"tcpmss" match support'
680 depends on NETFILTER_XTABLES
682 This option adds a `tcpmss' match, which allows you to examine the
683 MSS value of TCP SYN packets, which control the maximum packet size
686 To compile it as a module, choose M here. If unsure, say N.
688 config NETFILTER_XT_MATCH_TIME
689 tristate '"time" match support'
690 depends on NETFILTER_XTABLES
692 This option adds a "time" match, which allows you to match based on
693 the packet arrival time (at the machine which netfilter is running)
694 on) or departure time/date (for locally generated packets).
696 If you say Y here, try `iptables -m time --help` for
699 If you want to compile it as a module, say M here.
702 config NETFILTER_XT_MATCH_U32
703 tristate '"u32" match support'
704 depends on NETFILTER_XTABLES
706 u32 allows you to extract quantities of up to 4 bytes from a packet,
707 AND them with specified masks, shift them by specified amounts and
708 test whether the results are in any of a set of specified ranges.
709 The specification of what to extract is general enough to skip over
710 headers with lengths stored in the packet, as in IP or TCP header
713 Details and examples are in the kernel module source.
715 config NETFILTER_XT_MATCH_HASHLIMIT
716 tristate '"hashlimit" match support'
717 depends on NETFILTER_XTABLES && (IP6_NF_IPTABLES || IP6_NF_IPTABLES=n)
719 This option adds a `hashlimit' match.
721 As opposed to `limit', this match dynamically creates a hash table
722 of limit buckets, based on your selection of source/destination
723 addresses and/or ports.
725 It enables you to express policies like `10kpps for any given
726 destination address' or `500pps from any given source address'