net/netfilter/Kconfig

   1 menu "Core Netfilter Configuration"
   2         depends on NET && INET && NETFILTER
   3
   4 config NETFILTER_NETLINK
   5         tristate
   6
   7 config NETFILTER_NETLINK_ACCT
   8 tristate "Netfilter NFACCT 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 extended accounting via NFNETLINK.
  14
  15 config NETFILTER_NETLINK_QUEUE
  16         tristate "Netfilter NFQUEUE over NFNETLINK interface"
  17         depends on NETFILTER_ADVANCED
  18         select NETFILTER_NETLINK
  19         help
  20           If this option is enabled, the kernel will include support
  21           for queueing packets via NFNETLINK.
  22
  23 config NETFILTER_NETLINK_LOG
  24         tristate "Netfilter LOG over NFNETLINK interface"
  25         default m if NETFILTER_ADVANCED=n
  26         select NETFILTER_NETLINK
  27         help
  28           If this option is enabled, the kernel will include support
  29           for logging packets via NFNETLINK.
  30
  31           This obsoletes the existing ipt_ULOG and ebg_ulog mechanisms,
  32           and is also scheduled to replace the old syslog-based ipt_LOG
  33           and ip6t_LOG modules.
  34
  35 config NF_CONNTRACK
  36         tristate "Netfilter connection tracking support"
  37         default m if NETFILTER_ADVANCED=n
  38         help
  39           Connection tracking keeps a record of what packets have passed
  40           through your machine, in order to figure out how they are related
  41           into connections.
  42
  43           This is required to do Masquerading or other kinds of Network
  44           Address Translation.  It can also be used to enhance packet
  45           filtering (see `Connection state match support' below).
  46
  47           To compile it as a module, choose M here.  If unsure, say N.
  48
  49 if NF_CONNTRACK
  50
  51 config NF_CONNTRACK_MARK
  52         bool  'Connection mark tracking support'
  53         depends on NETFILTER_ADVANCED
  54         help
  55           This option enables support for connection marks, used by the
  56           `CONNMARK' target and `connmark' match. Similar to the mark value
  57           of packets, but this mark value is kept in the conntrack session
  58           instead of the individual packets.
  59
  60 config NF_CONNTRACK_SECMARK
  61         bool  'Connection tracking security mark support'
  62         depends on NETWORK_SECMARK
  63         default m if NETFILTER_ADVANCED=n
  64         help
  65           This option enables security markings to be applied to
  66           connections.  Typically they are copied to connections from
  67           packets using the CONNSECMARK target and copied back from
  68           connections to packets with the same target, with the packets
  69           being originally labeled via SECMARK.
  70
  71           If unsure, say 'N'.
  72
  73 config NF_CONNTRACK_ZONES
  74         bool  'Connection tracking zones'
  75         depends on NETFILTER_ADVANCED
  76         depends on NETFILTER_XT_TARGET_CT
  77         help
  78           This option enables support for connection tracking zones.
  79           Normally, each connection needs to have a unique system wide
  80           identity. Connection tracking zones allow to have multiple
  81           connections using the same identity, as long as they are
  82           contained in different zones.
  83
  84           If unsure, say `N'.
  85
  86 config NF_CONNTRACK_PROCFS
  87         bool "Supply CT list in procfs (OBSOLETE)"
  88         default y
  89         depends on PROC_FS
  90         ---help---
  91         This option enables for the list of known conntrack entries
  92         to be shown in procfs under net/netfilter/nf_conntrack. This
  93         is considered obsolete in favor of using the conntrack(8)
  94         tool which uses Netlink.
  95
  96 config NF_CONNTRACK_EVENTS
  97         bool "Connection tracking events"
  98         depends on NETFILTER_ADVANCED
  99         help
 100           If this option is enabled, the connection tracking code will
 101           provide a notifier chain that can be used by other kernel code
 102           to get notified about changes in the connection tracking state.
 103
 104           If unsure, say `N'.
 105
 106 config NF_CONNTRACK_TIMEOUT
 107         bool  'Connection tracking timeout'
 108         depends on NETFILTER_ADVANCED
 109         help
 110           This option enables support for connection tracking timeout
 111           extension. This allows you to attach timeout policies to flow
 112           via the CT target.
 113
 114           If unsure, say `N'.
 115
 116 config NF_CONNTRACK_TIMESTAMP
 117         bool  'Connection tracking timestamping'
 118         depends on NETFILTER_ADVANCED
 119         help
 120           This option enables support for connection tracking timestamping.
 121           This allows you to store the flow start-time and to obtain
 122           the flow-stop time (once it has been destroyed) via Connection
 123           tracking events.
 124
 125           If unsure, say `N'.
 126
 127 config NF_CONNTRACK_LABELS
 128         bool
 129         help
 130           This option enables support for assigning user-defined flag bits
 131           to connection tracking entries.  It selected by the connlabel match.
 132
 133 config NF_CT_PROTO_DCCP
 134         tristate 'DCCP protocol connection tracking support (EXPERIMENTAL)'
 135         depends on EXPERIMENTAL
 136         depends on NETFILTER_ADVANCED
 137         default IP_DCCP
 138         help
 139           With this option enabled, the layer 3 independent connection
 140           tracking code will be able to do state tracking on DCCP connections.
 141
 142           If unsure, say 'N'.
 143
 144 config NF_CT_PROTO_GRE
 145         tristate
 146
 147 config NF_CT_PROTO_SCTP
 148         tristate 'SCTP protocol connection tracking support (EXPERIMENTAL)'
 149         depends on EXPERIMENTAL
 150         depends on NETFILTER_ADVANCED
 151         default IP_SCTP
 152         help
 153           With this option enabled, the layer 3 independent connection
 154           tracking code will be able to do state tracking on SCTP connections.
 155
 156           If you want to compile it as a module, say M here and read
 157           <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.
 158
 159 config NF_CT_PROTO_UDPLITE
 160         tristate 'UDP-Lite protocol connection tracking support'
 161         depends on NETFILTER_ADVANCED
 162         help
 163           With this option enabled, the layer 3 independent connection
 164           tracking code will be able to do state tracking on UDP-Lite
 165           connections.
 166
 167           To compile it as a module, choose M here.  If unsure, say N.
 168
 169 config NF_CONNTRACK_AMANDA
 170         tristate "Amanda backup protocol support"
 171         depends on NETFILTER_ADVANCED
 172         select TEXTSEARCH
 173         select TEXTSEARCH_KMP
 174         help
 175           If you are running the Amanda backup package <http://www.amanda.org/>
 176           on this machine or machines that will be MASQUERADED through this
 177           machine, then you may want to enable this feature.  This allows the
 178           connection tracking and natting code to allow the sub-channels that
 179           Amanda requires for communication of the backup data, messages and
 180           index.
 181
 182           To compile it as a module, choose M here.  If unsure, say N.
 183
 184 config NF_CONNTRACK_FTP
 185         tristate "FTP protocol support"
 186         default m if NETFILTER_ADVANCED=n
 187         help
 188           Tracking FTP connections is problematic: special helpers are
 189           required for tracking them, and doing masquerading and other forms
 190           of Network Address Translation on them.
 191
 192           This is FTP support on Layer 3 independent connection tracking.
 193           Layer 3 independent connection tracking is experimental scheme
 194           which generalize ip_conntrack to support other layer 3 protocols.
 195
 196           To compile it as a module, choose M here.  If unsure, say N.
 197
 198 config NF_CONNTRACK_H323
 199         tristate "H.323 protocol support"
 200         depends on (IPV6 || IPV6=n)
 201         depends on NETFILTER_ADVANCED
 202         help
 203           H.323 is a VoIP signalling protocol from ITU-T. As one of the most
 204           important VoIP protocols, it is widely used by voice hardware and
 205           software including voice gateways, IP phones, Netmeeting, OpenPhone,
 206           Gnomemeeting, etc.
 207
 208           With this module you can support H.323 on a connection tracking/NAT
 209           firewall.
 210
 211           This module supports RAS, Fast Start, H.245 Tunnelling, Call
 212           Forwarding, RTP/RTCP and T.120 based audio, video, fax, chat,
 213           whiteboard, file transfer, etc. For more information, please
 214           visit http://nath323.sourceforge.net/.
 215
 216           To compile it as a module, choose M here.  If unsure, say N.
 217
 218 config NF_CONNTRACK_IRC
 219         tristate "IRC protocol support"
 220         default m if NETFILTER_ADVANCED=n
 221         help
 222           There is a commonly-used extension to IRC called
 223           Direct Client-to-Client Protocol (DCC).  This enables users to send
 224           files to each other, and also chat to each other without the need
 225           of a server.  DCC Sending is used anywhere you send files over IRC,
 226           and DCC Chat is most commonly used by Eggdrop bots.  If you are
 227           using NAT, this extension will enable you to send files and initiate
 228           chats.  Note that you do NOT need this extension to get files or
 229           have others initiate chats, or everything else in IRC.
 230
 231           To compile it as a module, choose M here.  If unsure, say N.
 232
 233 config NF_CONNTRACK_BROADCAST
 234         tristate
 235
 236 config NF_CONNTRACK_NETBIOS_NS
 237         tristate "NetBIOS name service protocol support"
 238         select NF_CONNTRACK_BROADCAST
 239         help
 240           NetBIOS name service requests are sent as broadcast messages from an
 241           unprivileged port and responded to with unicast messages to the
 242           same port. This make them hard to firewall properly because connection
 243           tracking doesn't deal with broadcasts. This helper tracks locally
 244           originating NetBIOS name service requests and the corresponding
 245           responses. It relies on correct IP address configuration, specifically
 246           netmask and broadcast address. When properly configured, the output
 247           of "ip address show" should look similar to this:
 248
 249           $ ip -4 address show eth0
 250           4: eth0: <BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 1000
 251               inet 172.16.2.252/24 brd 172.16.2.255 scope global eth0
 252
 253           To compile it as a module, choose M here.  If unsure, say N.
 254
 255 config NF_CONNTRACK_SNMP
 256         tristate "SNMP service protocol support"
 257         depends on NETFILTER_ADVANCED
 258         select NF_CONNTRACK_BROADCAST
 259         help
 260           SNMP service requests are sent as broadcast messages from an
 261           unprivileged port and responded to with unicast messages to the
 262           same port. This make them hard to firewall properly because connection
 263           tracking doesn't deal with broadcasts. This helper tracks locally
 264           originating SNMP service requests and the corresponding
 265           responses. It relies on correct IP address configuration, specifically
 266           netmask and broadcast address.
 267
 268           To compile it as a module, choose M here.  If unsure, say N.
 269
 270 config NF_CONNTRACK_PPTP
 271         tristate "PPtP protocol support"
 272         depends on NETFILTER_ADVANCED
 273         select NF_CT_PROTO_GRE
 274         help
 275           This module adds support for PPTP (Point to Point Tunnelling
 276           Protocol, RFC2637) connection tracking and NAT.
 277
 278           If you are running PPTP sessions over a stateful firewall or NAT
 279           box, you may want to enable this feature.
 280
 281           Please note that not all PPTP modes of operation are supported yet.
 282           Specifically these limitations exist:
 283             - Blindly assumes that control connections are always established
 284               in PNS->PAC direction. This is a violation of RFC2637.
 285             - Only supports a single call within each session
 286
 287           To compile it as a module, choose M here.  If unsure, say N.
 288
 289 config NF_CONNTRACK_SANE
 290         tristate "SANE protocol support (EXPERIMENTAL)"
 291         depends on EXPERIMENTAL
 292         depends on NETFILTER_ADVANCED
 293         help
 294           SANE is a protocol for remote access to scanners as implemented
 295           by the 'saned' daemon. Like FTP, it uses separate control and
 296           data connections.
 297
 298           With this module you can support SANE on a connection tracking
 299           firewall.
 300
 301           To compile it as a module, choose M here.  If unsure, say N.
 302
 303 config NF_CONNTRACK_SIP
 304         tristate "SIP protocol support"
 305         default m if NETFILTER_ADVANCED=n
 306         help
 307           SIP is an application-layer control protocol that can establish,
 308           modify, and terminate multimedia sessions (conferences) such as
 309           Internet telephony calls. With the ip_conntrack_sip and
 310           the nf_nat_sip modules you can support the protocol on a connection
 311           tracking/NATing firewall.
 312
 313           To compile it as a module, choose M here.  If unsure, say N.
 314
 315 config NF_CONNTRACK_TFTP
 316         tristate "TFTP protocol support"
 317         depends on NETFILTER_ADVANCED
 318         help
 319           TFTP connection tracking helper, this is required depending
 320           on how restrictive your ruleset is.
 321           If you are using a tftp client behind -j SNAT or -j MASQUERADING
 322           you will need this.
 323
 324           To compile it as a module, choose M here.  If unsure, say N.
 325
 326 config NF_CT_NETLINK
 327         tristate 'Connection tracking netlink interface'
 328         select NETFILTER_NETLINK
 329         default m if NETFILTER_ADVANCED=n
 330         help
 331           This option enables support for a netlink-based userspace interface
 332
 333 config NF_CT_NETLINK_TIMEOUT
 334         tristate  'Connection tracking timeout tuning via Netlink'
 335         select NETFILTER_NETLINK
 336         depends on NETFILTER_ADVANCED
 337         help
 338           This option enables support for connection tracking timeout
 339           fine-grain tuning. This allows you to attach specific timeout
 340           policies to flows, instead of using the global timeout policy.
 341
 342           If unsure, say `N'.
 343
 344 config NF_CT_NETLINK_HELPER
 345         tristate 'Connection tracking helpers in user-space via Netlink'
 346         select NETFILTER_NETLINK
 347         depends on NF_CT_NETLINK
 348         depends on NETFILTER_NETLINK_QUEUE
 349         depends on NETFILTER_NETLINK_QUEUE_CT
 350         depends on NETFILTER_ADVANCED
 351         help
 352           This option enables the user-space connection tracking helpers
 353           infrastructure.
 354
 355           If unsure, say `N'.
 356
 357 config NETFILTER_NETLINK_QUEUE_CT
 358         bool "NFQUEUE integration with Connection Tracking"
 359         default n
 360         depends on NETFILTER_NETLINK_QUEUE
 361         help
 362           If this option is enabled, NFQUEUE can include Connection Tracking
 363           information together with the packet is the enqueued via NFNETLINK.
 364
 365 config NF_NAT
 366         tristate
 367
 368 config NF_NAT_NEEDED
 369         bool
 370         depends on NF_NAT
 371         default y
 372
 373 config NF_NAT_PROTO_DCCP
 374         tristate
 375         depends on NF_NAT && NF_CT_PROTO_DCCP
 376         default NF_NAT && NF_CT_PROTO_DCCP
 377
 378 config NF_NAT_PROTO_UDPLITE
 379         tristate
 380         depends on NF_NAT && NF_CT_PROTO_UDPLITE
 381         default NF_NAT && NF_CT_PROTO_UDPLITE
 382
 383 config NF_NAT_PROTO_SCTP
 384         tristate
 385         default NF_NAT && NF_CT_PROTO_SCTP
 386         depends on NF_NAT && NF_CT_PROTO_SCTP
 387         select LIBCRC32C
 388
 389 config NF_NAT_AMANDA
 390         tristate
 391         depends on NF_CONNTRACK && NF_NAT
 392         default NF_NAT && NF_CONNTRACK_AMANDA
 393
 394 config NF_NAT_FTP
 395         tristate
 396         depends on NF_CONNTRACK && NF_NAT
 397         default NF_NAT && NF_CONNTRACK_FTP
 398
 399 config NF_NAT_IRC
 400         tristate
 401         depends on NF_CONNTRACK && NF_NAT
 402         default NF_NAT && NF_CONNTRACK_IRC
 403
 404 config NF_NAT_SIP
 405         tristate
 406         depends on NF_CONNTRACK && NF_NAT
 407         default NF_NAT && NF_CONNTRACK_SIP
 408
 409 config NF_NAT_TFTP
 410         tristate
 411         depends on NF_CONNTRACK && NF_NAT
 412         default NF_NAT && NF_CONNTRACK_TFTP
 413
 414 endif # NF_CONNTRACK
 415
 416 # transparent proxy support
 417 config NETFILTER_TPROXY
 418         tristate "Transparent proxying support (EXPERIMENTAL)"
 419         depends on EXPERIMENTAL
 420         depends on IP_NF_MANGLE
 421         depends on NETFILTER_ADVANCED
 422         help
 423           This option enables transparent proxying support, that is,
 424           support for handling non-locally bound IPv4 TCP and UDP sockets.
 425           For it to work you will have to configure certain iptables rules
 426           and use policy routing. For more information on how to set it up
 427           see Documentation/networking/tproxy.txt.
 428
 429           To compile it as a module, choose M here.  If unsure, say N.
 430
 431 config NETFILTER_XTABLES
 432         tristate "Netfilter Xtables support (required for ip_tables)"
 433         default m if NETFILTER_ADVANCED=n
 434         help
 435           This is required if you intend to use any of ip_tables,
 436           ip6_tables or arp_tables.
 437
 438 if NETFILTER_XTABLES
 439
 440 comment "Xtables combined modules"
 441
 442 config NETFILTER_XT_MARK
 443         tristate 'nfmark target and match support'
 444         default m if NETFILTER_ADVANCED=n
 445         ---help---
 446         This option adds the "MARK" target and "mark" match.
 447
 448         Netfilter mark matching allows you to match packets based on the
 449         "nfmark" value in the packet.
 450         The target allows you to create rules in the "mangle" table which alter
 451         the netfilter mark (nfmark) field associated with the packet.
 452
 453         Prior to routing, the nfmark can influence the routing method (see
 454         "Use netfilter MARK value as routing key") and can also be used by
 455         other subsystems to change their behavior.
 456
 457 config NETFILTER_XT_CONNMARK
 458         tristate 'ctmark target and match support'
 459         depends on NF_CONNTRACK
 460         depends on NETFILTER_ADVANCED
 461         select NF_CONNTRACK_MARK
 462         ---help---
 463         This option adds the "CONNMARK" target and "connmark" match.
 464
 465         Netfilter allows you to store a mark value per connection (a.k.a.
 466         ctmark), similarly to the packet mark (nfmark). Using this
 467         target and match, you can set and match on this mark.
 468
 469 config NETFILTER_XT_SET
 470         tristate 'set target and match support'
 471         depends on IP_SET
 472         depends on NETFILTER_ADVANCED
 473         help
 474           This option adds the "SET" target and "set" match.
 475
 476           Using this target and match, you can add/delete and match
 477           elements in the sets created by ipset(8).
 478
 479           To compile it as a module, choose M here.  If unsure, say N.
 480
 481 # alphabetically ordered list of targets
 482
 483 comment "Xtables targets"
 484
 485 config NETFILTER_XT_TARGET_AUDIT
 486         tristate "AUDIT target support"
 487         depends on AUDIT
 488         depends on NETFILTER_ADVANCED
 489         ---help---
 490           This option adds a 'AUDIT' target, which can be used to create
 491           audit records for packets dropped/accepted.
 492
 493           To compileit as a module, choose M here. If unsure, say N.
 494
 495 config NETFILTER_XT_TARGET_CHECKSUM
 496         tristate "CHECKSUM target support"
 497         depends on IP_NF_MANGLE || IP6_NF_MANGLE
 498         depends on NETFILTER_ADVANCED
 499         ---help---
 500           This option adds a `CHECKSUM' target, which can be used in the iptables mangle
 501           table.
 502
 503           You can use this target to compute and fill in the checksum in
 504           a packet that lacks a checksum.  This is particularly useful,
 505           if you need to work around old applications such as dhcp clients,
 506           that do not work well with checksum offloads, but don't want to disable
 507           checksum offload in your device.
 508
 509           To compile it as a module, choose M here.  If unsure, say N.
 510
 511 config NETFILTER_XT_TARGET_CLASSIFY
 512         tristate '"CLASSIFY" target support'
 513         depends on NETFILTER_ADVANCED
 514         help
 515           This option adds a `CLASSIFY' target, which enables the user to set
 516           the priority of a packet. Some qdiscs can use this value for
 517           classification, among these are:
 518
 519           atm, cbq, dsmark, pfifo_fast, htb, prio
 520
 521           To compile it as a module, choose M here.  If unsure, say N.
 522
 523 config NETFILTER_XT_TARGET_CONNMARK
 524         tristate  '"CONNMARK" target 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
 533 config NETFILTER_XT_TARGET_CONNSECMARK
 534         tristate '"CONNSECMARK" target support'
 535         depends on NF_CONNTRACK && NF_CONNTRACK_SECMARK
 536         default m if NETFILTER_ADVANCED=n
 537         help
 538           The CONNSECMARK target copies security markings from packets
 539           to connections, and restores security markings from connections
 540           to packets (if the packets are not already marked).  This would
 541           normally be used in conjunction with the SECMARK target.
 542
 543           To compile it as a module, choose M here.  If unsure, say N.
 544
 545 config NETFILTER_XT_TARGET_CT
 546         tristate '"CT" target support'
 547         depends on NF_CONNTRACK
 548         depends on IP_NF_RAW || IP6_NF_RAW
 549         depends on NETFILTER_ADVANCED
 550         help
 551           This options adds a `CT' target, which allows to specify initial
 552           connection tracking parameters like events to be delivered and
 553           the helper to be used.
 554
 555           To compile it as a module, choose M here.  If unsure, say N.
 556
 557 config NETFILTER_XT_TARGET_DSCP
 558         tristate '"DSCP" and "TOS" target support'
 559         depends on IP_NF_MANGLE || IP6_NF_MANGLE
 560         depends on NETFILTER_ADVANCED
 561         help
 562           This option adds a `DSCP' target, which allows you to manipulate
 563           the IPv4/IPv6 header DSCP field (differentiated services codepoint).
 564
 565           The DSCP field can have any value between 0x0 and 0x3f inclusive.
 566
 567           It also adds the "TOS" target, which allows you to create rules in
 568           the "mangle" table which alter the Type Of Service field of an IPv4
 569           or the Priority field of an IPv6 packet, prior to routing.
 570
 571           To compile it as a module, choose M here.  If unsure, say N.
 572
 573 config NETFILTER_XT_TARGET_HL
 574         tristate '"HL" hoplimit target support'
 575         depends on IP_NF_MANGLE || IP6_NF_MANGLE
 576         depends on NETFILTER_ADVANCED
 577         ---help---
 578         This option adds the "HL" (for IPv6) and "TTL" (for IPv4)
 579         targets, which enable the user to change the
 580         hoplimit/time-to-live value of the IP header.
 581
 582         While it is safe to decrement the hoplimit/TTL value, the
 583         modules also allow to increment and set the hoplimit value of
 584         the header to arbitrary values. This is EXTREMELY DANGEROUS
 585         since you can easily create immortal packets that loop
 586         forever on the network.
 587
 588 config NETFILTER_XT_TARGET_HMARK
 589         tristate '"HMARK" target support'
 590         depends on (IP6_NF_IPTABLES || IP6_NF_IPTABLES=n)
 591         depends on NETFILTER_ADVANCED
 592         ---help---
 593         This option adds the "HMARK" target.
 594
 595         The target allows you to create rules in the "raw" and "mangle" tables
 596         which set the skbuff mark by means of hash calculation within a given
 597         range. The nfmark can influence the routing method (see "Use netfilter
 598         MARK value as routing key") and can also be used by other subsystems to
 599         change their behaviour.
 600
 601         To compile it as a module, choose M here. If unsure, say N.
 602
 603 config NETFILTER_XT_TARGET_IDLETIMER
 604         tristate  "IDLETIMER target support"
 605         depends on NETFILTER_ADVANCED
 606         help
 607
 608           This option adds the `IDLETIMER' target.  Each matching packet
 609           resets the timer associated with label specified when the rule is
 610           added.  When the timer expires, it triggers a sysfs notification.
 611           The remaining time for expiration can be read via sysfs.
 612
 613           To compile it as a module, choose M here.  If unsure, say N.
 614
 615 config NETFILTER_XT_TARGET_LED
 616         tristate '"LED" target support'
 617         depends on LEDS_CLASS && LEDS_TRIGGERS
 618         depends on NETFILTER_ADVANCED
 619         help
 620           This option adds a `LED' target, which allows you to blink LEDs in
 621           response to particular packets passing through your machine.
 622
 623           This can be used to turn a spare LED into a network activity LED,
 624           which only flashes in response to FTP transfers, for example.  Or
 625           you could have an LED which lights up for a minute or two every time
 626           somebody connects to your machine via SSH.
 627
 628           You will need support for the "led" class to make this work.
 629
 630           To create an LED trigger for incoming SSH traffic:
 631             iptables -A INPUT -p tcp --dport 22 -j LED --led-trigger-id ssh --led-delay 1000
 632
 633           Then attach the new trigger to an LED on your system:
 634             echo netfilter-ssh > /sys/class/leds/<ledname>/trigger
 635
 636           For more information on the LEDs available on your system, see
 637           Documentation/leds/leds-class.txt
 638
 639 config NETFILTER_XT_TARGET_LOG
 640         tristate "LOG target support"
 641         default m if NETFILTER_ADVANCED=n
 642         help
 643           This option adds a `LOG' target, which allows you to create rules in
 644           any iptables table which records the packet header to the syslog.
 645
 646           To compile it as a module, choose M here.  If unsure, say N.
 647
 648 config NETFILTER_XT_TARGET_MARK
 649         tristate '"MARK" target support'
 650         depends on NETFILTER_ADVANCED
 651         select NETFILTER_XT_MARK
 652         ---help---
 653         This is a backwards-compat option for the user's convenience
 654         (e.g. when running oldconfig). It selects
 655         CONFIG_NETFILTER_XT_MARK (combined mark/MARK module).
 656
 657 config NETFILTER_XT_TARGET_NETMAP
 658         tristate '"NETMAP" target support'
 659         depends on NF_NAT
 660         ---help---
 661         NETMAP is an implementation of static 1:1 NAT mapping of network
 662         addresses. It maps the network address part, while keeping the host
 663         address part intact.
 664
 665         To compile it as a module, choose M here. If unsure, say N.
 666
 667 config NETFILTER_XT_TARGET_NFLOG
 668         tristate '"NFLOG" target support'
 669         default m if NETFILTER_ADVANCED=n
 670         select NETFILTER_NETLINK_LOG
 671         help
 672           This option enables the NFLOG target, which allows to LOG
 673           messages through nfnetlink_log.
 674
 675           To compile it as a module, choose M here.  If unsure, say N.
 676
 677 config NETFILTER_XT_TARGET_NFQUEUE
 678         tristate '"NFQUEUE" target Support'
 679         depends on NETFILTER_ADVANCED
 680         select NETFILTER_NETLINK_QUEUE
 681         help
 682           This target replaced the old obsolete QUEUE target.
 683
 684           As opposed to QUEUE, it supports 65535 different queues,
 685           not just one.
 686
 687           To compile it as a module, choose M here.  If unsure, say N.
 688
 689 config NETFILTER_XT_TARGET_NOTRACK
 690         tristate  '"NOTRACK" target support (DEPRECATED)'
 691         depends on NF_CONNTRACK
 692         depends on IP_NF_RAW || IP6_NF_RAW
 693         depends on NETFILTER_ADVANCED
 694         select NETFILTER_XT_TARGET_CT
 695
 696 config NETFILTER_XT_TARGET_RATEEST
 697         tristate '"RATEEST" target support'
 698         depends on NETFILTER_ADVANCED
 699         help
 700           This option adds a `RATEEST' target, which allows to measure
 701           rates similar to TC estimators. The `rateest' match can be
 702           used to match on the measured rates.
 703
 704           To compile it as a module, choose M here.  If unsure, say N.
 705
 706 config NETFILTER_XT_TARGET_REDIRECT
 707         tristate "REDIRECT target support"
 708         depends on NF_NAT
 709         ---help---
 710         REDIRECT is a special case of NAT: all incoming connections are
 711         mapped onto the incoming interface's address, causing the packets to
 712         come to the local machine instead of passing through. This is
 713         useful for transparent proxies.
 714
 715         To compile it as a module, choose M here. If unsure, say N.
 716
 717 config NETFILTER_XT_TARGET_TEE
 718         tristate '"TEE" - packet cloning to alternate destination'
 719         depends on NETFILTER_ADVANCED
 720         depends on (IPV6 || IPV6=n)
 721         depends on !NF_CONNTRACK || NF_CONNTRACK
 722         ---help---
 723         This option adds a "TEE" target with which a packet can be cloned and
 724         this clone be rerouted to another nexthop.
 725
 726 config NETFILTER_XT_TARGET_TPROXY
 727         tristate '"TPROXY" target support (EXPERIMENTAL)'
 728         depends on EXPERIMENTAL
 729         depends on NETFILTER_TPROXY
 730         depends on NETFILTER_XTABLES
 731         depends on NETFILTER_ADVANCED
 732         select NF_DEFRAG_IPV4
 733         select NF_DEFRAG_IPV6 if IP6_NF_IPTABLES
 734         help
 735           This option adds a `TPROXY' target, which is somewhat similar to
 736           REDIRECT.  It can only be used in the mangle table and is useful
 737           to redirect traffic to a transparent proxy.  It does _not_ depend
 738           on Netfilter connection tracking and NAT, unlike REDIRECT.
 739
 740           To compile it as a module, choose M here.  If unsure, say N.
 741
 742 config NETFILTER_XT_TARGET_TRACE
 743         tristate  '"TRACE" target support'
 744         depends on IP_NF_RAW || IP6_NF_RAW
 745         depends on NETFILTER_ADVANCED
 746         help
 747           The TRACE target allows you to mark packets so that the kernel
 748           will log every rule which match the packets as those traverse
 749           the tables, chains, rules.
 750
 751           If you want to compile it as a module, say M here and read
 752           <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.
 753
 754 config NETFILTER_XT_TARGET_SECMARK
 755         tristate '"SECMARK" target support'
 756         depends on NETWORK_SECMARK
 757         default m if NETFILTER_ADVANCED=n
 758         help
 759           The SECMARK target allows security marking of network
 760           packets, for use with security subsystems.
 761
 762           To compile it as a module, choose M here.  If unsure, say N.
 763
 764 config NETFILTER_XT_TARGET_TCPMSS
 765         tristate '"TCPMSS" target support'
 766         depends on (IPV6 || IPV6=n)
 767         default m if NETFILTER_ADVANCED=n
 768         ---help---
 769           This option adds a `TCPMSS' target, which allows you to alter the
 770           MSS value of TCP SYN packets, to control the maximum size for that
 771           connection (usually limiting it to your outgoing interface's MTU
 772           minus 40).
 773
 774           This is used to overcome criminally braindead ISPs or servers which
 775           block ICMP Fragmentation Needed packets.  The symptoms of this
 776           problem are that everything works fine from your Linux
 777           firewall/router, but machines behind it can never exchange large
 778           packets:
 779                 1) Web browsers connect, then hang with no data received.
 780                 2) Small mail works fine, but large emails hang.
 781                 3) ssh works fine, but scp hangs after initial handshaking.
 782
 783           Workaround: activate this option and add a rule to your firewall
 784           configuration like:
 785
 786           iptables -A FORWARD -p tcp --tcp-flags SYN,RST SYN \
 787                          -j TCPMSS --clamp-mss-to-pmtu
 788
 789           To compile it as a module, choose M here.  If unsure, say N.
 790
 791 config NETFILTER_XT_TARGET_TCPOPTSTRIP
 792         tristate '"TCPOPTSTRIP" target support (EXPERIMENTAL)'
 793         depends on EXPERIMENTAL
 794         depends on IP_NF_MANGLE || IP6_NF_MANGLE
 795         depends on NETFILTER_ADVANCED
 796         help
 797           This option adds a "TCPOPTSTRIP" target, which allows you to strip
 798           TCP options from TCP packets.
 799
 800 # alphabetically ordered list of matches
 801
 802 comment "Xtables matches"
 803
 804 config NETFILTER_XT_MATCH_ADDRTYPE
 805         tristate '"addrtype" address type match support'
 806         depends on NETFILTER_ADVANCED
 807         ---help---
 808           This option allows you to match what routing thinks of an address,
 809           eg. UNICAST, LOCAL, BROADCAST, ...
 810
 811           If you want to compile it as a module, say M here and read
 812           <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.
 813
 814 config NETFILTER_XT_MATCH_BPF
 815         tristate '"bpf" match support'
 816         depends on NETFILTER_ADVANCED
 817         help
 818           BPF matching applies a linux socket filter to each packet and
 819           accepts those for which the filter returns non-zero.
 820
 821           To compile it as a module, choose M here.  If unsure, say N.
 822
 823 config NETFILTER_XT_MATCH_CLUSTER
 824         tristate '"cluster" match support'
 825         depends on NF_CONNTRACK
 826         depends on NETFILTER_ADVANCED
 827         ---help---
 828           This option allows you to build work-load-sharing clusters of
 829           network servers/stateful firewalls without having a dedicated
 830           load-balancing router/server/switch. Basically, this match returns
 831           true when the packet must be handled by this cluster node. Thus,
 832           all nodes see all packets and this match decides which node handles
 833           what packets. The work-load sharing algorithm is based on source
 834           address hashing.
 835
 836           If you say Y or M here, try `iptables -m cluster --help` for
 837           more information.
 838
 839 config NETFILTER_XT_MATCH_COMMENT
 840         tristate  '"comment" match support'
 841         depends on NETFILTER_ADVANCED
 842         help
 843           This option adds a `comment' dummy-match, which allows you to put
 844           comments in your iptables ruleset.
 845
 846           If you want to compile it as a module, say M here and read
 847           <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.
 848
 849 config NETFILTER_XT_MATCH_CONNBYTES
 850         tristate  '"connbytes" per-connection counter match support'
 851         depends on NF_CONNTRACK
 852         depends on NETFILTER_ADVANCED
 853         help
 854           This option adds a `connbytes' match, which allows you to match the
 855           number of bytes and/or packets for each direction within a connection.
 856
 857           If you want to compile it as a module, say M here and read
 858           <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.
 859
 860 config NETFILTER_XT_MATCH_CONNLABEL
 861         tristate '"connlabel" match support'
 862         select NF_CONNTRACK_LABELS
 863         depends on NF_CONNTRACK
 864         depends on NETFILTER_ADVANCED
 865         ---help---
 866           This match allows you to test and assign userspace-defined labels names
 867           to a connection.  The kernel only stores bit values - mapping
 868           names to bits is done by userspace.
 869
 870           Unlike connmark, more than 32 flag bits may be assigned to a
 871           connection simultaneously.
 872
 873 config NETFILTER_XT_MATCH_CONNLIMIT
 874         tristate '"connlimit" match support"'
 875         depends on NF_CONNTRACK
 876         depends on NETFILTER_ADVANCED
 877         ---help---
 878           This match allows you to match against the number of parallel
 879           connections to a server per client IP address (or address block).
 880
 881 config NETFILTER_XT_MATCH_CONNMARK
 882         tristate  '"connmark" connection mark match support'
 883         depends on NF_CONNTRACK
 884         depends on NETFILTER_ADVANCED
 885         select NETFILTER_XT_CONNMARK
 886         ---help---
 887         This is a backwards-compat option for the user's convenience
 888         (e.g. when running oldconfig). It selects
 889         CONFIG_NETFILTER_XT_CONNMARK (combined connmark/CONNMARK module).
 890
 891 config NETFILTER_XT_MATCH_CONNTRACK
 892         tristate '"conntrack" connection tracking match support'
 893         depends on NF_CONNTRACK
 894         default m if NETFILTER_ADVANCED=n
 895         help
 896           This is a general conntrack match module, a superset of the state match.
 897
 898           It allows matching on additional conntrack information, which is
 899           useful in complex configurations, such as NAT gateways with multiple
 900           internet links or tunnels.
 901
 902           To compile it as a module, choose M here.  If unsure, say N.
 903
 904 config NETFILTER_XT_MATCH_CPU
 905         tristate '"cpu" match support'
 906         depends on NETFILTER_ADVANCED
 907         help
 908           CPU matching allows you to match packets based on the CPU
 909           currently handling the packet.
 910
 911           To compile it as a module, choose M here.  If unsure, say N.
 912
 913 config NETFILTER_XT_MATCH_DCCP
 914         tristate '"dccp" protocol match support'
 915         depends on NETFILTER_ADVANCED
 916         default IP_DCCP
 917         help
 918           With this option enabled, you will be able to use the iptables
 919           `dccp' match in order to match on DCCP source/destination ports
 920           and DCCP flags.
 921
 922           If you want to compile it as a module, say M here and read
 923           <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.
 924
 925 config NETFILTER_XT_MATCH_DEVGROUP
 926         tristate '"devgroup" match support'
 927         depends on NETFILTER_ADVANCED
 928         help
 929           This options adds a `devgroup' match, which allows to match on the
 930           device group a network device is assigned to.
 931
 932           To compile it as a module, choose M here.  If unsure, say N.
 933
 934 config NETFILTER_XT_MATCH_DSCP
 935         tristate '"dscp" and "tos" match support'
 936         depends on NETFILTER_ADVANCED
 937         help
 938           This option adds a `DSCP' match, which allows you to match against
 939           the IPv4/IPv6 header DSCP field (differentiated services codepoint).
 940
 941           The DSCP field can have any value between 0x0 and 0x3f inclusive.
 942
 943           It will also add a "tos" match, which allows you to match packets
 944           based on the Type Of Service fields of the IPv4 packet (which share
 945           the same bits as DSCP).
 946
 947           To compile it as a module, choose M here.  If unsure, say N.
 948
 949 config NETFILTER_XT_MATCH_ECN
 950         tristate '"ecn" match support'
 951         depends on NETFILTER_ADVANCED
 952         ---help---
 953         This option adds an "ECN" match, which allows you to match against
 954         the IPv4 and TCP header ECN fields.
 955
 956         To compile it as a module, choose M here. If unsure, say N.
 957
 958 config NETFILTER_XT_MATCH_ESP
 959         tristate '"esp" match support'
 960         depends on NETFILTER_ADVANCED
 961         help
 962           This match extension allows you to match a range of SPIs
 963           inside ESP header of IPSec packets.
 964
 965           To compile it as a module, choose M here.  If unsure, say N.
 966
 967 config NETFILTER_XT_MATCH_HASHLIMIT
 968         tristate '"hashlimit" match support'
 969         depends on (IP6_NF_IPTABLES || IP6_NF_IPTABLES=n)
 970         depends on NETFILTER_ADVANCED
 971         help
 972           This option adds a `hashlimit' match.
 973
 974           As opposed to `limit', this match dynamically creates a hash table
 975           of limit buckets, based on your selection of source/destination
 976           addresses and/or ports.
 977
 978           It enables you to express policies like `10kpps for any given
 979           destination address' or `500pps from any given source address'
 980           with a single rule.
 981
 982 config NETFILTER_XT_MATCH_HELPER
 983         tristate '"helper" match support'
 984         depends on NF_CONNTRACK
 985         depends on NETFILTER_ADVANCED
 986         help
 987           Helper matching allows you to match packets in dynamic connections
 988           tracked by a conntrack-helper, ie. ip_conntrack_ftp
 989
 990           To compile it as a module, choose M here.  If unsure, say Y.
 991
 992 config NETFILTER_XT_MATCH_HL
 993         tristate '"hl" hoplimit/TTL match support'
 994         depends on NETFILTER_ADVANCED
 995         ---help---
 996         HL matching allows you to match packets based on the hoplimit
 997         in the IPv6 header, or the time-to-live field in the IPv4
 998         header of the packet.
 999
1000 config NETFILTER_XT_MATCH_IPRANGE
1001         tristate '"iprange" address range match support'
1002         depends on NETFILTER_ADVANCED
1003         ---help---
1004         This option adds a "iprange" match, which allows you to match based on
1005         an IP address range. (Normal iptables only matches on single addresses
1006         with an optional mask.)
1007
1008         If unsure, say M.
1009
1010 config NETFILTER_XT_MATCH_IPVS
1011         tristate '"ipvs" match support'
1012         depends on IP_VS
1013         depends on NETFILTER_ADVANCED
1014         depends on NF_CONNTRACK
1015         help
1016           This option allows you to match against IPVS properties of a packet.
1017
1018           If unsure, say N.
1019
1020 config NETFILTER_XT_MATCH_LENGTH
1021         tristate '"length" match support'
1022         depends on NETFILTER_ADVANCED
1023         help
1024           This option allows you to match the length of a packet against a
1025           specific value or range of values.
1026
1027           To compile it as a module, choose M here.  If unsure, say N.
1028
1029 config NETFILTER_XT_MATCH_LIMIT
1030         tristate '"limit" match support'
1031         depends on NETFILTER_ADVANCED
1032         help
1033           limit matching allows you to control the rate at which a rule can be
1034           matched: mainly useful in combination with the LOG target ("LOG
1035           target support", below) and to avoid some Denial of Service attacks.
1036
1037           To compile it as a module, choose M here.  If unsure, say N.
1038
1039 config NETFILTER_XT_MATCH_MAC
1040         tristate '"mac" address match support'
1041         depends on NETFILTER_ADVANCED
1042         help
1043           MAC matching allows you to match packets based on the source
1044           Ethernet address of the packet.
1045
1046           To compile it as a module, choose M here.  If unsure, say N.
1047
1048 config NETFILTER_XT_MATCH_MARK
1049         tristate '"mark" match support'
1050         depends on NETFILTER_ADVANCED
1051         select NETFILTER_XT_MARK
1052         ---help---
1053         This is a backwards-compat option for the user's convenience
1054         (e.g. when running oldconfig). It selects
1055         CONFIG_NETFILTER_XT_MARK (combined mark/MARK module).
1056
1057 config NETFILTER_XT_MATCH_MULTIPORT
1058         tristate '"multiport" Multiple port match support'
1059         depends on NETFILTER_ADVANCED
1060         help
1061           Multiport matching allows you to match TCP or UDP packets based on
1062           a series of source or destination ports: normally a rule can only
1063           match a single range of ports.
1064
1065           To compile it as a module, choose M here.  If unsure, say N.
1066
1067 config NETFILTER_XT_MATCH_NFACCT
1068         tristate '"nfacct" match support'
1069         depends on NETFILTER_ADVANCED
1070         select NETFILTER_NETLINK_ACCT
1071         help
1072           This option allows you to use the extended accounting through
1073           nfnetlink_acct.
1074
1075           To compile it as a module, choose M here.  If unsure, say N.
1076
1077 config NETFILTER_XT_MATCH_OSF
1078         tristate '"osf" Passive OS fingerprint match'
1079         depends on NETFILTER_ADVANCED && NETFILTER_NETLINK
1080         help
1081           This option selects the Passive OS Fingerprinting match module
1082           that allows to passively match the remote operating system by
1083           analyzing incoming TCP SYN packets.
1084
1085           Rules and loading software can be downloaded from
1086           http://www.ioremap.net/projects/osf
1087
1088           To compile it as a module, choose M here.  If unsure, say N.
1089
1090 config NETFILTER_XT_MATCH_OWNER
1091         tristate '"owner" match support'
1092         depends on NETFILTER_ADVANCED
1093         ---help---
1094         Socket owner matching allows you to match locally-generated packets
1095         based on who created the socket: the user or group. It is also
1096         possible to check whether a socket actually exists.
1097
1098 config NETFILTER_XT_MATCH_POLICY
1099         tristate 'IPsec "policy" match support'
1100         depends on XFRM
1101         default m if NETFILTER_ADVANCED=n
1102         help
1103           Policy matching allows you to match packets based on the
1104           IPsec policy that was used during decapsulation/will
1105           be used during encapsulation.
1106
1107           To compile it as a module, choose M here.  If unsure, say N.
1108
1109 config NETFILTER_XT_MATCH_PHYSDEV
1110         tristate '"physdev" match support'
1111         depends on BRIDGE && BRIDGE_NETFILTER
1112         depends on NETFILTER_ADVANCED
1113         help
1114           Physdev packet matching matches against the physical bridge ports
1115           the IP packet arrived on or will leave by.
1116
1117           To compile it as a module, choose M here.  If unsure, say N.
1118
1119 config NETFILTER_XT_MATCH_PKTTYPE
1120         tristate '"pkttype" packet type match support'
1121         depends on NETFILTER_ADVANCED
1122         help
1123           Packet type matching allows you to match a packet by
1124           its "class", eg. BROADCAST, MULTICAST, ...
1125
1126           Typical usage:
1127           iptables -A INPUT -m pkttype --pkt-type broadcast -j LOG
1128
1129           To compile it as a module, choose M here.  If unsure, say N.
1130
1131 config NETFILTER_XT_MATCH_QUOTA
1132         tristate '"quota" match support'
1133         depends on NETFILTER_ADVANCED
1134         help
1135           This option adds a `quota' match, which allows to match on a
1136           byte counter.
1137
1138           If you want to compile it as a module, say M here and read
1139           <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.
1140
1141 config NETFILTER_XT_MATCH_RATEEST
1142         tristate '"rateest" match support'
1143         depends on NETFILTER_ADVANCED
1144         select NETFILTER_XT_TARGET_RATEEST
1145         help
1146           This option adds a `rateest' match, which allows to match on the
1147           rate estimated by the RATEEST target.
1148
1149           To compile it as a module, choose M here.  If unsure, say N.
1150
1151 config NETFILTER_XT_MATCH_REALM
1152         tristate  '"realm" match support'
1153         depends on NETFILTER_ADVANCED
1154         select IP_ROUTE_CLASSID
1155         help
1156           This option adds a `realm' match, which allows you to use the realm
1157           key from the routing subsystem inside iptables.
1158
1159           This match pretty much resembles the CONFIG_NET_CLS_ROUTE4 option
1160           in tc world.
1161
1162           If you want to compile it as a module, say M here and read
1163           <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.
1164
1165 config NETFILTER_XT_MATCH_RECENT
1166         tristate '"recent" match support'
1167         depends on NETFILTER_ADVANCED
1168         ---help---
1169         This match is used for creating one or many lists of recently
1170         used addresses and then matching against that/those list(s).
1171
1172         Short options are available by using 'iptables -m recent -h'
1173         Official Website: <http://snowman.net/projects/ipt_recent/>
1174
1175 config NETFILTER_XT_MATCH_SCTP
1176         tristate  '"sctp" protocol match support (EXPERIMENTAL)'
1177         depends on EXPERIMENTAL
1178         depends on NETFILTER_ADVANCED
1179         default IP_SCTP
1180         help
1181           With this option enabled, you will be able to use the
1182           `sctp' match in order to match on SCTP source/destination ports
1183           and SCTP chunk types.
1184
1185           If you want to compile it as a module, say M here and read
1186           <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.
1187
1188 config NETFILTER_XT_MATCH_SOCKET
1189         tristate '"socket" match support (EXPERIMENTAL)'
1190         depends on EXPERIMENTAL
1191         depends on NETFILTER_TPROXY
1192         depends on NETFILTER_XTABLES
1193         depends on NETFILTER_ADVANCED
1194         depends on !NF_CONNTRACK || NF_CONNTRACK
1195         select NF_DEFRAG_IPV4
1196         select NF_DEFRAG_IPV6 if IP6_NF_IPTABLES
1197         help
1198           This option adds a `socket' match, which can be used to match
1199           packets for which a TCP or UDP socket lookup finds a valid socket.
1200           It can be used in combination with the MARK target and policy
1201           routing to implement full featured non-locally bound sockets.
1202
1203           To compile it as a module, choose M here.  If unsure, say N.
1204
1205 config NETFILTER_XT_MATCH_STATE
1206         tristate '"state" match support'
1207         depends on NF_CONNTRACK
1208         default m if NETFILTER_ADVANCED=n
1209         help
1210           Connection state matching allows you to match packets based on their
1211           relationship to a tracked connection (ie. previous packets).  This
1212           is a powerful tool for packet classification.
1213
1214           To compile it as a module, choose M here.  If unsure, say N.
1215
1216 config NETFILTER_XT_MATCH_STATISTIC
1217         tristate '"statistic" match support'
1218         depends on NETFILTER_ADVANCED
1219         help
1220           This option adds a `statistic' match, which allows you to match
1221           on packets periodically or randomly with a given percentage.
1222
1223           To compile it as a module, choose M here.  If unsure, say N.
1224
1225 config NETFILTER_XT_MATCH_STRING
1226         tristate  '"string" match support'
1227         depends on NETFILTER_ADVANCED
1228         select TEXTSEARCH
1229         select TEXTSEARCH_KMP
1230         select TEXTSEARCH_BM
1231         select TEXTSEARCH_FSM
1232         help
1233           This option adds a `string' match, which allows you to look for
1234           pattern matchings in packets.
1235
1236           To compile it as a module, choose M here.  If unsure, say N.
1237
1238 config NETFILTER_XT_MATCH_TCPMSS
1239         tristate '"tcpmss" match support'
1240         depends on NETFILTER_ADVANCED
1241         help
1242           This option adds a `tcpmss' match, which allows you to examine the
1243           MSS value of TCP SYN packets, which control the maximum packet size
1244           for that connection.
1245
1246           To compile it as a module, choose M here.  If unsure, say N.
1247
1248 config NETFILTER_XT_MATCH_TIME
1249         tristate '"time" match support'
1250         depends on NETFILTER_ADVANCED
1251         ---help---
1252           This option adds a "time" match, which allows you to match based on
1253           the packet arrival time (at the machine which netfilter is running)
1254           on) or departure time/date (for locally generated packets).
1255
1256           If you say Y here, try `iptables -m time --help` for
1257           more information.
1258
1259           If you want to compile it as a module, say M here.
1260           If unsure, say N.
1261
1262 config NETFILTER_XT_MATCH_U32
1263         tristate '"u32" match support'
1264         depends on NETFILTER_ADVANCED
1265         ---help---
1266           u32 allows you to extract quantities of up to 4 bytes from a packet,
1267           AND them with specified masks, shift them by specified amounts and
1268           test whether the results are in any of a set of specified ranges.
1269           The specification of what to extract is general enough to skip over
1270           headers with lengths stored in the packet, as in IP or TCP header
1271           lengths.
1272
1273           Details and examples are in the kernel module source.
1274
1275 endif # NETFILTER_XTABLES
1276
1277 endmenu
1278
1279 source "net/netfilter/ipset/Kconfig"
1280
1281 source "net/netfilter/ipvs/Kconfig"