doc: fix broken references

[mirror_ubuntu-jammy-kernel.git] / net / netfilter / Kconfig

menu "Core Netfilter Configuration"
        depends on NET && INET && NETFILTER

config NETFILTER_NETLINK
        tristate

config NETFILTER_NETLINK_QUEUE
        tristate "Netfilter NFQUEUE over NFNETLINK interface"
        depends on NETFILTER_ADVANCED
        select NETFILTER_NETLINK
        help
          If this option is enabled, the kernel will include support
          for queueing packets via NFNETLINK.
          
config NETFILTER_NETLINK_LOG
        tristate "Netfilter LOG over NFNETLINK interface"
        default m if NETFILTER_ADVANCED=n
        select NETFILTER_NETLINK
        help
          If this option is enabled, the kernel will include support
          for logging packets via NFNETLINK.

          This obsoletes the existing ipt_ULOG and ebg_ulog mechanisms,
          and is also scheduled to replace the old syslog-based ipt_LOG
          and ip6t_LOG modules.

config NF_CONNTRACK
        tristate "Netfilter connection tracking support"
        default m if NETFILTER_ADVANCED=n
        help
          Connection tracking keeps a record of what packets have passed
          through your machine, in order to figure out how they are related
          into connections.

          This is required to do Masquerading or other kinds of Network
          Address Translation.  It can also be used to enhance packet
          filtering (see `Connection state match support' below).

          To compile it as a module, choose M here.  If unsure, say N.

if NF_CONNTRACK

config NF_CONNTRACK_MARK
        bool  'Connection mark tracking support'
        depends on NETFILTER_ADVANCED
        help
          This option enables support for connection marks, used by the
          `CONNMARK' target and `connmark' match. Similar to the mark value
          of packets, but this mark value is kept in the conntrack session
          instead of the individual packets.

config NF_CONNTRACK_SECMARK
        bool  'Connection tracking security mark support'
        depends on NETWORK_SECMARK
        default m if NETFILTER_ADVANCED=n
        help
          This option enables security markings to be applied to
          connections.  Typically they are copied to connections from
          packets using the CONNSECMARK target and copied back from
          connections to packets with the same target, with the packets
          being originally labeled via SECMARK.

          If unsure, say 'N'.

config NF_CONNTRACK_ZONES
        bool  'Connection tracking zones'
        depends on NETFILTER_ADVANCED
        depends on NETFILTER_XT_TARGET_CT
        help
          This option enables support for connection tracking zones.
          Normally, each connection needs to have a unique system wide
          identity. Connection tracking zones allow to have multiple
          connections using the same identity, as long as they are
          contained in different zones.

          If unsure, say `N'.

config NF_CONNTRACK_EVENTS
        bool "Connection tracking events"
        depends on NETFILTER_ADVANCED
        help
          If this option is enabled, the connection tracking code will
          provide a notifier chain that can be used by other kernel code
          to get notified about changes in the connection tracking state.

          If unsure, say `N'.

config NF_CONNTRACK_TIMESTAMP
        bool  'Connection tracking timestamping'
        depends on NETFILTER_ADVANCED
        help
          This option enables support for connection tracking timestamping.
          This allows you to store the flow start-time and to obtain
          the flow-stop time (once it has been destroyed) via Connection
          tracking events.

          If unsure, say `N'.

config NF_CT_PROTO_DCCP
        tristate 'DCCP protocol connection tracking support (EXPERIMENTAL)'
        depends on EXPERIMENTAL
        depends on NETFILTER_ADVANCED
        default IP_DCCP
        help
          With this option enabled, the layer 3 independent connection
          tracking code will be able to do state tracking on DCCP connections.

          If unsure, say 'N'.

config NF_CT_PROTO_GRE
        tristate

config NF_CT_PROTO_SCTP
        tristate 'SCTP protocol connection tracking support (EXPERIMENTAL)'
        depends on EXPERIMENTAL
        depends on NETFILTER_ADVANCED
        default IP_SCTP
        help
          With this option enabled, the layer 3 independent connection
          tracking code will be able to do state tracking on SCTP connections.

          If you want to compile it as a module, say M here and read
          <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.

config NF_CT_PROTO_UDPLITE
        tristate 'UDP-Lite protocol connection tracking support'
        depends on NETFILTER_ADVANCED
        help
          With this option enabled, the layer 3 independent connection
          tracking code will be able to do state tracking on UDP-Lite
          connections.

          To compile it as a module, choose M here.  If unsure, say N.

config NF_CONNTRACK_AMANDA
        tristate "Amanda backup protocol support"
        depends on NETFILTER_ADVANCED
        select TEXTSEARCH
        select TEXTSEARCH_KMP
        help
          If you are running the Amanda backup package <http://www.amanda.org/>
          on this machine or machines that will be MASQUERADED through this
          machine, then you may want to enable this feature.  This allows the
          connection tracking and natting code to allow the sub-channels that
          Amanda requires for communication of the backup data, messages and
          index.

          To compile it as a module, choose M here.  If unsure, say N.

config NF_CONNTRACK_FTP
        tristate "FTP protocol support"
        default m if NETFILTER_ADVANCED=n
        help
          Tracking FTP connections is problematic: special helpers are
          required for tracking them, and doing masquerading and other forms
          of Network Address Translation on them.

          This is FTP support on Layer 3 independent connection tracking.
          Layer 3 independent connection tracking is experimental scheme
          which generalize ip_conntrack to support other layer 3 protocols.

          To compile it as a module, choose M here.  If unsure, say N.

config NF_CONNTRACK_H323
        tristate "H.323 protocol support"
        depends on (IPV6 || IPV6=n)
        depends on NETFILTER_ADVANCED
        help
          H.323 is a VoIP signalling protocol from ITU-T. As one of the most
          important VoIP protocols, it is widely used by voice hardware and
          software including voice gateways, IP phones, Netmeeting, OpenPhone,
          Gnomemeeting, etc.

          With this module you can support H.323 on a connection tracking/NAT
          firewall.

          This module supports RAS, Fast Start, H.245 Tunnelling, Call
          Forwarding, RTP/RTCP and T.120 based audio, video, fax, chat,
          whiteboard, file transfer, etc. For more information, please
          visit http://nath323.sourceforge.net/.

          To compile it as a module, choose M here.  If unsure, say N.

config NF_CONNTRACK_IRC
        tristate "IRC protocol support"
        default m if NETFILTER_ADVANCED=n
        help
          There is a commonly-used extension to IRC called
          Direct Client-to-Client Protocol (DCC).  This enables users to send
          files to each other, and also chat to each other without the need
          of a server.  DCC Sending is used anywhere you send files over IRC,
          and DCC Chat is most commonly used by Eggdrop bots.  If you are
          using NAT, this extension will enable you to send files and initiate
          chats.  Note that you do NOT need this extension to get files or
          have others initiate chats, or everything else in IRC.

          To compile it as a module, choose M here.  If unsure, say N.

config NF_CONNTRACK_BROADCAST
        tristate

config NF_CONNTRACK_NETBIOS_NS
        tristate "NetBIOS name service protocol support"
        depends on NETFILTER_ADVANCED
        select NF_CONNTRACK_BROADCAST
        help
          NetBIOS name service requests are sent as broadcast messages from an
          unprivileged port and responded to with unicast messages to the
          same port. This make them hard to firewall properly because connection
          tracking doesn't deal with broadcasts. This helper tracks locally
          originating NetBIOS name service requests and the corresponding
          responses. It relies on correct IP address configuration, specifically
          netmask and broadcast address. When properly configured, the output
          of "ip address show" should look similar to this:

          $ ip -4 address show eth0
          4: eth0: <BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 1000
              inet 172.16.2.252/24 brd 172.16.2.255 scope global eth0

          To compile it as a module, choose M here.  If unsure, say N.

config NF_CONNTRACK_SNMP
        tristate "SNMP service protocol support"
        depends on NETFILTER_ADVANCED
        select NF_CONNTRACK_BROADCAST
        help
          SNMP service requests are sent as broadcast messages from an
          unprivileged port and responded to with unicast messages to the
          same port. This make them hard to firewall properly because connection
          tracking doesn't deal with broadcasts. This helper tracks locally
          originating SNMP service requests and the corresponding
          responses. It relies on correct IP address configuration, specifically
          netmask and broadcast address.

          To compile it as a module, choose M here.  If unsure, say N.

config NF_CONNTRACK_PPTP
        tristate "PPtP protocol support"
        depends on NETFILTER_ADVANCED
        select NF_CT_PROTO_GRE
        help
          This module adds support for PPTP (Point to Point Tunnelling
          Protocol, RFC2637) connection tracking and NAT.

          If you are running PPTP sessions over a stateful firewall or NAT
          box, you may want to enable this feature.

          Please note that not all PPTP modes of operation are supported yet.
          Specifically these limitations exist:
            - Blindly assumes that control connections are always established
              in PNS->PAC direction. This is a violation of RFC2637.
            - Only supports a single call within each session

          To compile it as a module, choose M here.  If unsure, say N.

config NF_CONNTRACK_SANE
        tristate "SANE protocol support (EXPERIMENTAL)"
        depends on EXPERIMENTAL
        depends on NETFILTER_ADVANCED
        help
          SANE is a protocol for remote access to scanners as implemented
          by the 'saned' daemon. Like FTP, it uses separate control and
          data connections.

          With this module you can support SANE on a connection tracking
          firewall.

          To compile it as a module, choose M here.  If unsure, say N.

config NF_CONNTRACK_SIP
        tristate "SIP protocol support"
        default m if NETFILTER_ADVANCED=n
        help
          SIP is an application-layer control protocol that can establish,
          modify, and terminate multimedia sessions (conferences) such as
          Internet telephony calls. With the ip_conntrack_sip and
          the nf_nat_sip modules you can support the protocol on a connection
          tracking/NATing firewall.

          To compile it as a module, choose M here.  If unsure, say N.

config NF_CONNTRACK_TFTP
        tristate "TFTP protocol support"
        depends on NETFILTER_ADVANCED
        help
          TFTP connection tracking helper, this is required depending
          on how restrictive your ruleset is.
          If you are using a tftp client behind -j SNAT or -j MASQUERADING
          you will need this.

          To compile it as a module, choose M here.  If unsure, say N.

config NF_CT_NETLINK
        tristate 'Connection tracking netlink interface'
        select NETFILTER_NETLINK
        default m if NETFILTER_ADVANCED=n
        help
          This option enables support for a netlink-based userspace interface

endif # NF_CONNTRACK

# transparent proxy support
config NETFILTER_TPROXY
        tristate "Transparent proxying support (EXPERIMENTAL)"
        depends on EXPERIMENTAL
        depends on IP_NF_MANGLE
        depends on NETFILTER_ADVANCED
        help
          This option enables transparent proxying support, that is,
          support for handling non-locally bound IPv4 TCP and UDP sockets.
          For it to work you will have to configure certain iptables rules
          and use policy routing. For more information on how to set it up
          see Documentation/networking/tproxy.txt.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XTABLES
        tristate "Netfilter Xtables support (required for ip_tables)"
        default m if NETFILTER_ADVANCED=n
        help
          This is required if you intend to use any of ip_tables,
          ip6_tables or arp_tables.

if NETFILTER_XTABLES

comment "Xtables combined modules"

config NETFILTER_XT_MARK
        tristate 'nfmark target and match support'
        default m if NETFILTER_ADVANCED=n
        ---help---
        This option adds the "MARK" target and "mark" match.

        Netfilter mark matching allows you to match packets based on the
        "nfmark" value in the packet.
        The target allows you to create rules in the "mangle" table which alter
        the netfilter mark (nfmark) field associated with the packet.

        Prior to routing, the nfmark can influence the routing method (see
        "Use netfilter MARK value as routing key") and can also be used by
        other subsystems to change their behavior.

config NETFILTER_XT_CONNMARK
        tristate 'ctmark target and match support'
        depends on NF_CONNTRACK
        depends on NETFILTER_ADVANCED
        select NF_CONNTRACK_MARK
        ---help---
        This option adds the "CONNMARK" target and "connmark" match.

        Netfilter allows you to store a mark value per connection (a.k.a.
        ctmark), similarly to the packet mark (nfmark). Using this
        target and match, you can set and match on this mark.

config NETFILTER_XT_SET
        tristate 'set target and match support'
        depends on IP_SET
        depends on NETFILTER_ADVANCED
        help
          This option adds the "SET" target and "set" match.

          Using this target and match, you can add/delete and match
          elements in the sets created by ipset(8).

          To compile it as a module, choose M here.  If unsure, say N.

# alphabetically ordered list of targets

comment "Xtables targets"

config NETFILTER_XT_TARGET_AUDIT
        tristate "AUDIT target support"
        depends on AUDIT
        depends on NETFILTER_ADVANCED
        ---help---
          This option adds a 'AUDIT' target, which can be used to create
          audit records for packets dropped/accepted.

          To compileit as a module, choose M here. If unsure, say N.

config NETFILTER_XT_TARGET_CHECKSUM
        tristate "CHECKSUM target support"
        depends on IP_NF_MANGLE || IP6_NF_MANGLE
        depends on NETFILTER_ADVANCED
        ---help---
          This option adds a `CHECKSUM' target, which can be used in the iptables mangle
          table.

          You can use this target to compute and fill in the checksum in
          a packet that lacks a checksum.  This is particularly useful,
          if you need to work around old applications such as dhcp clients,
          that do not work well with checksum offloads, but don't want to disable
          checksum offload in your device.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_TARGET_CLASSIFY
        tristate '"CLASSIFY" target support'
        depends on NETFILTER_ADVANCED
        help
          This option adds a `CLASSIFY' target, which enables the user to set
          the priority of a packet. Some qdiscs can use this value for
          classification, among these are:

          atm, cbq, dsmark, pfifo_fast, htb, prio

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_TARGET_CONNMARK
        tristate  '"CONNMARK" target support'
        depends on NF_CONNTRACK
        depends on NETFILTER_ADVANCED
        select NETFILTER_XT_CONNMARK
        ---help---
        This is a backwards-compat option for the user's convenience
        (e.g. when running oldconfig). It selects
        CONFIG_NETFILTER_XT_CONNMARK (combined connmark/CONNMARK module).

config NETFILTER_XT_TARGET_CONNSECMARK
        tristate '"CONNSECMARK" target support'
        depends on NF_CONNTRACK && NF_CONNTRACK_SECMARK
        default m if NETFILTER_ADVANCED=n
        help
          The CONNSECMARK target copies security markings from packets
          to connections, and restores security markings from connections
          to packets (if the packets are not already marked).  This would
          normally be used in conjunction with the SECMARK target.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_TARGET_CT
        tristate '"CT" target support'
        depends on NF_CONNTRACK
        depends on IP_NF_RAW || IP6_NF_RAW
        depends on NETFILTER_ADVANCED
        help
          This options adds a `CT' target, which allows to specify initial
          connection tracking parameters like events to be delivered and
          the helper to be used.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_TARGET_DSCP
        tristate '"DSCP" and "TOS" target support'
        depends on IP_NF_MANGLE || IP6_NF_MANGLE
        depends on NETFILTER_ADVANCED
        help
          This option adds a `DSCP' target, which allows you to manipulate
          the IPv4/IPv6 header DSCP field (differentiated services codepoint).

          The DSCP field can have any value between 0x0 and 0x3f inclusive.

          It also adds the "TOS" target, which allows you to create rules in
          the "mangle" table which alter the Type Of Service field of an IPv4
          or the Priority field of an IPv6 packet, prior to routing.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_TARGET_HL
        tristate '"HL" hoplimit target support'
        depends on IP_NF_MANGLE || IP6_NF_MANGLE
        depends on NETFILTER_ADVANCED
        ---help---
        This option adds the "HL" (for IPv6) and "TTL" (for IPv4)
        targets, which enable the user to change the
        hoplimit/time-to-live value of the IP header.

        While it is safe to decrement the hoplimit/TTL value, the
        modules also allow to increment and set the hoplimit value of
        the header to arbitrary values. This is EXTREMELY DANGEROUS
        since you can easily create immortal packets that loop
        forever on the network.

config NETFILTER_XT_TARGET_IDLETIMER
        tristate  "IDLETIMER target support"
        depends on NETFILTER_ADVANCED
        help

          This option adds the `IDLETIMER' target.  Each matching packet
          resets the timer associated with label specified when the rule is
          added.  When the timer expires, it triggers a sysfs notification.
          The remaining time for expiration can be read via sysfs.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_TARGET_LED
        tristate '"LED" target support'
        depends on LEDS_CLASS && LEDS_TRIGGERS
        depends on NETFILTER_ADVANCED
        help
          This option adds a `LED' target, which allows you to blink LEDs in
          response to particular packets passing through your machine.

          This can be used to turn a spare LED into a network activity LED,
          which only flashes in response to FTP transfers, for example.  Or
          you could have an LED which lights up for a minute or two every time
          somebody connects to your machine via SSH.

          You will need support for the "led" class to make this work.

          To create an LED trigger for incoming SSH traffic:
            iptables -A INPUT -p tcp --dport 22 -j LED --led-trigger-id ssh --led-delay 1000

          Then attach the new trigger to an LED on your system:
            echo netfilter-ssh > /sys/class/leds/<ledname>/trigger

          For more information on the LEDs available on your system, see
          Documentation/leds/leds-class.txt

config NETFILTER_XT_TARGET_MARK
        tristate '"MARK" target support'
        depends on NETFILTER_ADVANCED
        select NETFILTER_XT_MARK
        ---help---
        This is a backwards-compat option for the user's convenience
        (e.g. when running oldconfig). It selects
        CONFIG_NETFILTER_XT_MARK (combined mark/MARK module).

config NETFILTER_XT_TARGET_NFLOG
        tristate '"NFLOG" target support'
        default m if NETFILTER_ADVANCED=n
        select NETFILTER_NETLINK_LOG
        help
          This option enables the NFLOG target, which allows to LOG
          messages through nfnetlink_log.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_TARGET_NFQUEUE
        tristate '"NFQUEUE" target Support'
        depends on NETFILTER_ADVANCED
        select NETFILTER_NETLINK_QUEUE
        help
          This target replaced the old obsolete QUEUE target.

          As opposed to QUEUE, it supports 65535 different queues,
          not just one.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_TARGET_NOTRACK
        tristate  '"NOTRACK" target support'
        depends on IP_NF_RAW || IP6_NF_RAW
        depends on NF_CONNTRACK
        depends on NETFILTER_ADVANCED
        help
          The NOTRACK target allows a select rule to specify
          which packets *not* to enter the conntrack/NAT
          subsystem with all the consequences (no ICMP error tracking,
          no protocol helpers for the selected packets).

          If you want to compile it as a module, say M here and read
          <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.

config NETFILTER_XT_TARGET_RATEEST
        tristate '"RATEEST" target support'
        depends on NETFILTER_ADVANCED
        help
          This option adds a `RATEEST' target, which allows to measure
          rates similar to TC estimators. The `rateest' match can be
          used to match on the measured rates.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_TARGET_TEE
        tristate '"TEE" - packet cloning to alternate destination'
        depends on NETFILTER_ADVANCED
        depends on (IPV6 || IPV6=n)
        depends on !NF_CONNTRACK || NF_CONNTRACK
        ---help---
        This option adds a "TEE" target with which a packet can be cloned and
        this clone be rerouted to another nexthop.

config NETFILTER_XT_TARGET_TPROXY
        tristate '"TPROXY" target support (EXPERIMENTAL)'
        depends on EXPERIMENTAL
        depends on NETFILTER_TPROXY
        depends on NETFILTER_XTABLES
        depends on NETFILTER_ADVANCED
        select NF_DEFRAG_IPV4
        select NF_DEFRAG_IPV6 if IP6_NF_IPTABLES
        help
          This option adds a `TPROXY' target, which is somewhat similar to
          REDIRECT.  It can only be used in the mangle table and is useful
          to redirect traffic to a transparent proxy.  It does _not_ depend
          on Netfilter connection tracking and NAT, unlike REDIRECT.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_TARGET_TRACE
        tristate  '"TRACE" target support'
        depends on IP_NF_RAW || IP6_NF_RAW
        depends on NETFILTER_ADVANCED
        help
          The TRACE target allows you to mark packets so that the kernel
          will log every rule which match the packets as those traverse
          the tables, chains, rules.

          If you want to compile it as a module, say M here and read
          <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.

config NETFILTER_XT_TARGET_SECMARK
        tristate '"SECMARK" target support'
        depends on NETWORK_SECMARK
        default m if NETFILTER_ADVANCED=n
        help
          The SECMARK target allows security marking of network
          packets, for use with security subsystems.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_TARGET_TCPMSS
        tristate '"TCPMSS" target support'
        depends on (IPV6 || IPV6=n)
        default m if NETFILTER_ADVANCED=n
        ---help---
          This option adds a `TCPMSS' target, which allows you to alter the
          MSS value of TCP SYN packets, to control the maximum size for that
          connection (usually limiting it to your outgoing interface's MTU
          minus 40).

          This is used to overcome criminally braindead ISPs or servers which
          block ICMP Fragmentation Needed packets.  The symptoms of this
          problem are that everything works fine from your Linux
          firewall/router, but machines behind it can never exchange large
          packets:
                1) Web browsers connect, then hang with no data received.
                2) Small mail works fine, but large emails hang.
                3) ssh works fine, but scp hangs after initial handshaking.

          Workaround: activate this option and add a rule to your firewall
          configuration like:

          iptables -A FORWARD -p tcp --tcp-flags SYN,RST SYN \
                         -j TCPMSS --clamp-mss-to-pmtu

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_TARGET_TCPOPTSTRIP
        tristate '"TCPOPTSTRIP" target support (EXPERIMENTAL)'
        depends on EXPERIMENTAL
        depends on IP_NF_MANGLE || IP6_NF_MANGLE
        depends on NETFILTER_ADVANCED
        help
          This option adds a "TCPOPTSTRIP" target, which allows you to strip
          TCP options from TCP packets.

# alphabetically ordered list of matches

comment "Xtables matches"

config NETFILTER_XT_MATCH_ADDRTYPE
        tristate '"addrtype" address type match support'
        depends on NETFILTER_ADVANCED
        ---help---
          This option allows you to match what routing thinks of an address,
          eg. UNICAST, LOCAL, BROADCAST, ...

          If you want to compile it as a module, say M here and read
          <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.

config NETFILTER_XT_MATCH_CLUSTER
        tristate '"cluster" match support'
        depends on NF_CONNTRACK
        depends on NETFILTER_ADVANCED
        ---help---
          This option allows you to build work-load-sharing clusters of
          network servers/stateful firewalls without having a dedicated
          load-balancing router/server/switch. Basically, this match returns
          true when the packet must be handled by this cluster node. Thus,
          all nodes see all packets and this match decides which node handles
          what packets. The work-load sharing algorithm is based on source
          address hashing.

          If you say Y or M here, try `iptables -m cluster --help` for
          more information.

config NETFILTER_XT_MATCH_COMMENT
        tristate  '"comment" match support'
        depends on NETFILTER_ADVANCED
        help
          This option adds a `comment' dummy-match, which allows you to put
          comments in your iptables ruleset.

          If you want to compile it as a module, say M here and read
          <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.

config NETFILTER_XT_MATCH_CONNBYTES
        tristate  '"connbytes" per-connection counter match support'
        depends on NF_CONNTRACK
        depends on NETFILTER_ADVANCED
        help
          This option adds a `connbytes' match, which allows you to match the
          number of bytes and/or packets for each direction within a connection.

          If you want to compile it as a module, say M here and read
          <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.

config NETFILTER_XT_MATCH_CONNLIMIT
        tristate '"connlimit" match support"'
        depends on NF_CONNTRACK
        depends on NETFILTER_ADVANCED
        ---help---
          This match allows you to match against the number of parallel
          connections to a server per client IP address (or address block).

config NETFILTER_XT_MATCH_CONNMARK
        tristate  '"connmark" connection mark match support'
        depends on NF_CONNTRACK
        depends on NETFILTER_ADVANCED
        select NETFILTER_XT_CONNMARK
        ---help---
        This is a backwards-compat option for the user's convenience
        (e.g. when running oldconfig). It selects
        CONFIG_NETFILTER_XT_CONNMARK (combined connmark/CONNMARK module).

config NETFILTER_XT_MATCH_CONNTRACK
        tristate '"conntrack" connection tracking match support'
        depends on NF_CONNTRACK
        default m if NETFILTER_ADVANCED=n
        help
          This is a general conntrack match module, a superset of the state match.

          It allows matching on additional conntrack information, which is
          useful in complex configurations, such as NAT gateways with multiple
          internet links or tunnels.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_MATCH_CPU
        tristate '"cpu" match support'
        depends on NETFILTER_ADVANCED
        help
          CPU matching allows you to match packets based on the CPU
          currently handling the packet.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_MATCH_DCCP
        tristate '"dccp" protocol match support'
        depends on NETFILTER_ADVANCED
        default IP_DCCP
        help
          With this option enabled, you will be able to use the iptables
          `dccp' match in order to match on DCCP source/destination ports
          and DCCP flags.

          If you want to compile it as a module, say M here and read
          <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.

config NETFILTER_XT_MATCH_DEVGROUP
        tristate '"devgroup" match support'
        depends on NETFILTER_ADVANCED
        help
          This options adds a `devgroup' match, which allows to match on the
          device group a network device is assigned to.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_MATCH_DSCP
        tristate '"dscp" and "tos" match support'
        depends on NETFILTER_ADVANCED
        help
          This option adds a `DSCP' match, which allows you to match against
          the IPv4/IPv6 header DSCP field (differentiated services codepoint).

          The DSCP field can have any value between 0x0 and 0x3f inclusive.

          It will also add a "tos" match, which allows you to match packets
          based on the Type Of Service fields of the IPv4 packet (which share
          the same bits as DSCP).

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_MATCH_ESP
        tristate '"esp" match support'
        depends on NETFILTER_ADVANCED
        help
          This match extension allows you to match a range of SPIs
          inside ESP header of IPSec packets.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_MATCH_HASHLIMIT
        tristate '"hashlimit" match support'
        depends on (IP6_NF_IPTABLES || IP6_NF_IPTABLES=n)
        depends on NETFILTER_ADVANCED
        help
          This option adds a `hashlimit' match.

          As opposed to `limit', this match dynamically creates a hash table
          of limit buckets, based on your selection of source/destination
          addresses and/or ports.

          It enables you to express policies like `10kpps for any given
          destination address' or `500pps from any given source address'
          with a single rule.

config NETFILTER_XT_MATCH_HELPER
        tristate '"helper" match support'
        depends on NF_CONNTRACK
        depends on NETFILTER_ADVANCED
        help
          Helper matching allows you to match packets in dynamic connections
          tracked by a conntrack-helper, ie. ip_conntrack_ftp

          To compile it as a module, choose M here.  If unsure, say Y.

config NETFILTER_XT_MATCH_HL
        tristate '"hl" hoplimit/TTL match support'
        depends on NETFILTER_ADVANCED
        ---help---
        HL matching allows you to match packets based on the hoplimit
        in the IPv6 header, or the time-to-live field in the IPv4
        header of the packet.

config NETFILTER_XT_MATCH_IPRANGE
        tristate '"iprange" address range match support'
        depends on NETFILTER_ADVANCED
        ---help---
        This option adds a "iprange" match, which allows you to match based on
        an IP address range. (Normal iptables only matches on single addresses
        with an optional mask.)

        If unsure, say M.

config NETFILTER_XT_MATCH_IPVS
        tristate '"ipvs" match support'
        depends on IP_VS
        depends on NETFILTER_ADVANCED
        depends on NF_CONNTRACK
        help
          This option allows you to match against IPVS properties of a packet.

          If unsure, say N.

config NETFILTER_XT_MATCH_LENGTH
        tristate '"length" match support'
        depends on NETFILTER_ADVANCED
        help
          This option allows you to match the length of a packet against a
          specific value or range of values.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_MATCH_LIMIT
        tristate '"limit" match support'
        depends on NETFILTER_ADVANCED
        help
          limit matching allows you to control the rate at which a rule can be
          matched: mainly useful in combination with the LOG target ("LOG
          target support", below) and to avoid some Denial of Service attacks.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_MATCH_MAC
        tristate '"mac" address match support'
        depends on NETFILTER_ADVANCED
        help
          MAC matching allows you to match packets based on the source
          Ethernet address of the packet.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_MATCH_MARK
        tristate '"mark" match support'
        depends on NETFILTER_ADVANCED
        select NETFILTER_XT_MARK
        ---help---
        This is a backwards-compat option for the user's convenience
        (e.g. when running oldconfig). It selects
        CONFIG_NETFILTER_XT_MARK (combined mark/MARK module).

config NETFILTER_XT_MATCH_MULTIPORT
        tristate '"multiport" Multiple port match support'
        depends on NETFILTER_ADVANCED
        help
          Multiport matching allows you to match TCP or UDP packets based on
          a series of source or destination ports: normally a rule can only
          match a single range of ports.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_MATCH_OSF
        tristate '"osf" Passive OS fingerprint match'
        depends on NETFILTER_ADVANCED && NETFILTER_NETLINK
        help
          This option selects the Passive OS Fingerprinting match module
          that allows to passively match the remote operating system by
          analyzing incoming TCP SYN packets.

          Rules and loading software can be downloaded from
          http://www.ioremap.net/projects/osf

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_MATCH_OWNER
        tristate '"owner" match support'
        depends on NETFILTER_ADVANCED
        ---help---
        Socket owner matching allows you to match locally-generated packets
        based on who created the socket: the user or group. It is also
        possible to check whether a socket actually exists.

config NETFILTER_XT_MATCH_POLICY
        tristate 'IPsec "policy" match support'
        depends on XFRM
        default m if NETFILTER_ADVANCED=n
        help
          Policy matching allows you to match packets based on the
          IPsec policy that was used during decapsulation/will
          be used during encapsulation.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_MATCH_PHYSDEV
        tristate '"physdev" match support'
        depends on BRIDGE && BRIDGE_NETFILTER
        depends on NETFILTER_ADVANCED
        help
          Physdev packet matching matches against the physical bridge ports
          the IP packet arrived on or will leave by.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_MATCH_PKTTYPE
        tristate '"pkttype" packet type match support'
        depends on NETFILTER_ADVANCED
        help
          Packet type matching allows you to match a packet by
          its "class", eg. BROADCAST, MULTICAST, ...

          Typical usage:
          iptables -A INPUT -m pkttype --pkt-type broadcast -j LOG

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_MATCH_QUOTA
        tristate '"quota" match support'
        depends on NETFILTER_ADVANCED
        help
          This option adds a `quota' match, which allows to match on a
          byte counter.

          If you want to compile it as a module, say M here and read
          <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.

config NETFILTER_XT_MATCH_RATEEST
        tristate '"rateest" match support'
        depends on NETFILTER_ADVANCED
        select NETFILTER_XT_TARGET_RATEEST
        help
          This option adds a `rateest' match, which allows to match on the
          rate estimated by the RATEEST target.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_MATCH_REALM
        tristate  '"realm" match support'
        depends on NETFILTER_ADVANCED
        select IP_ROUTE_CLASSID
        help
          This option adds a `realm' match, which allows you to use the realm
          key from the routing subsystem inside iptables.

          This match pretty much resembles the CONFIG_NET_CLS_ROUTE4 option 
          in tc world.

          If you want to compile it as a module, say M here and read
          <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.

config NETFILTER_XT_MATCH_RECENT
        tristate '"recent" match support'
        depends on NETFILTER_ADVANCED
        ---help---
        This match is used for creating one or many lists of recently
        used addresses and then matching against that/those list(s).

        Short options are available by using 'iptables -m recent -h'
        Official Website: <http://snowman.net/projects/ipt_recent/>

config NETFILTER_XT_MATCH_SCTP
        tristate  '"sctp" protocol match support (EXPERIMENTAL)'
        depends on EXPERIMENTAL
        depends on NETFILTER_ADVANCED
        default IP_SCTP
        help
          With this option enabled, you will be able to use the 
          `sctp' match in order to match on SCTP source/destination ports
          and SCTP chunk types.

          If you want to compile it as a module, say M here and read
          <file:Documentation/kbuild/modules.txt>.  If unsure, say `N'.

config NETFILTER_XT_MATCH_SOCKET
        tristate '"socket" match support (EXPERIMENTAL)'
        depends on EXPERIMENTAL
        depends on NETFILTER_TPROXY
        depends on NETFILTER_XTABLES
        depends on NETFILTER_ADVANCED
        depends on !NF_CONNTRACK || NF_CONNTRACK
        select NF_DEFRAG_IPV4
        select NF_DEFRAG_IPV6 if IP6_NF_IPTABLES
        help
          This option adds a `socket' match, which can be used to match
          packets for which a TCP or UDP socket lookup finds a valid socket.
          It can be used in combination with the MARK target and policy
          routing to implement full featured non-locally bound sockets.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_MATCH_STATE
        tristate '"state" match support'
        depends on NF_CONNTRACK
        default m if NETFILTER_ADVANCED=n
        help
          Connection state matching allows you to match packets based on their
          relationship to a tracked connection (ie. previous packets).  This
          is a powerful tool for packet classification.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_MATCH_STATISTIC
        tristate '"statistic" match support'
        depends on NETFILTER_ADVANCED
        help
          This option adds a `statistic' match, which allows you to match
          on packets periodically or randomly with a given percentage.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_MATCH_STRING
        tristate  '"string" match support'
        depends on NETFILTER_ADVANCED
        select TEXTSEARCH
        select TEXTSEARCH_KMP
        select TEXTSEARCH_BM
        select TEXTSEARCH_FSM
        help
          This option adds a `string' match, which allows you to look for
          pattern matchings in packets.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_MATCH_TCPMSS
        tristate '"tcpmss" match support'
        depends on NETFILTER_ADVANCED
        help
          This option adds a `tcpmss' match, which allows you to examine the
          MSS value of TCP SYN packets, which control the maximum packet size
          for that connection.

          To compile it as a module, choose M here.  If unsure, say N.

config NETFILTER_XT_MATCH_TIME
        tristate '"time" match support'
        depends on NETFILTER_ADVANCED
        ---help---
          This option adds a "time" match, which allows you to match based on
          the packet arrival time (at the machine which netfilter is running)
          on) or departure time/date (for locally generated packets).

          If you say Y here, try `iptables -m time --help` for
          more information.

          If you want to compile it as a module, say M here.
          If unsure, say N.

config NETFILTER_XT_MATCH_U32
        tristate '"u32" match support'
        depends on NETFILTER_ADVANCED
        ---help---
          u32 allows you to extract quantities of up to 4 bytes from a packet,
          AND them with specified masks, shift them by specified amounts and
          test whether the results are in any of a set of specified ranges.
          The specification of what to extract is general enough to skip over
          headers with lengths stored in the packet, as in IP or TCP header
          lengths.

          Details and examples are in the kernel module source.

endif # NETFILTER_XTABLES

endmenu

source "net/netfilter/ipset/Kconfig"

source "net/netfilter/ipvs/Kconfig"