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IP6TABLES(8)							  IP6TABLES(8)

NAME
       ip6tables - IPv6 packet filter administration

SYNOPSIS
       ip6tables [-t table] -[AD] chain rule-specification [options]
       ip6tables [-t table] -I chain [rulenum] rule-specification [options]
       ip6tables [-t table] -R chain rulenum rule-specification [options]
       ip6tables [-t table] -D chain rulenum [options]
       ip6tables [-t table] -[LFZ] [chain] [options]
       ip6tables [-t table] -N chain
       ip6tables [-t table] -X [chain]
       ip6tables [-t table] -P chain target [options]
       ip6tables [-t table] -E old-chain-name new-chain-name

DESCRIPTION
       Ip6tables  is  used to set up, maintain, and inspect the tables of IPv6
       packet filter rules in the Linux kernel.	 Several different tables  may
       be  defined.   Each  table contains a number of built-in chains and may
       also contain user-defined chains.

       Each chain is a list of rules which can match a set of  packets.	  Each
       rule specifies what to do with a packet that matches.  This is called a
       `target', which may be a jump to a user-defined chain in the  same  ta‐
       ble.

TARGETS
       A  firewall rule specifies criteria for a packet, and a target.	If the
       packet does not match, the next rule in the chain is the	 examined;  if
       it does match, then the next rule is specified by the value of the tar‐
       get, which can be the name of a user-defined chain or one of  the  spe‐
       cial values ACCEPT, DROP, QUEUE, or RETURN.

       ACCEPT  means to let the packet through.	 DROP means to drop the packet
       on the floor.  QUEUE means to pass the packet to userspace.   (How  the
       packet can be received by a userspace process differs by the particular
       queue handler.  2.4.x and  2.6.x	 kernels  up  to  2.6.13  include  the
       ip_queue	 queue handler.	 Kernels 2.6.14 and later additionally include
       the nfnetlink_queue queue handler.  Packets with a target of QUEUE will
       be  sent	 to queue number '0' in this case. Please also see the NFQUEUE
       target as described  later  in  this  man  page.)   RETURN  means  stop
       traversing  this	 chain	and  resume  at	 the next rule in the previous
       (calling) chain.	 If the end of a built-in chain is reached or  a  rule
       in a built-in chain with target RETURN is matched, the target specified
       by the chain policy determines the fate of the packet.

TABLES
       There are currently two independent tables (which tables are present at
       any  time depends on the kernel configuration options and which modules
       are present), as nat table has not been implemented yet.

       -t, --table table
	      This option specifies the packet matching table which  the  com‐
	      mand  should operate on.	If the kernel is configured with auto‐
	      matic module loading, an attempt will be made to load the appro‐
	      priate module for that table if it is not already there.

	      The tables are as follows:

	      filter:
		  This	is  the default table (if no -t option is passed).  It
		  contains the built-in chains INPUT (for packets coming  into
		  the  box  itself), FORWARD (for packets being routed through
		  the box), and OUTPUT (for locally-generated packets).

	      mangle:
		  This table is used for specialized packet alteration.	 Until
		  kernel  2.4.17  it  had two built-in chains: PREROUTING (for
		  altering incoming packets before routing)  and  OUTPUT  (for
		  altering  locally-generated  packets before routing).	 Since
		  kernel 2.4.18, three other built-in  chains  are  also  sup‐
		  ported: INPUT (for packets coming into the box itself), FOR‐
		  WARD (for altering packets being routed  through  the	 box),
		  and  POSTROUTING  (for altering packets as they are about to
		  go out).

	      raw:
		  This table is used mainly for	 configuring  exemptions  from
		  connection  tracking in combination with the NOTRACK target.
		  It registers at the netfilter hooks with higher priority and
		  is thus called before nf_conntrack, or any other IP6 tables.
		  It provides the following built-in chains:  PREROUTING  (for
		  packets  arriving  via  any  network	interface) OUTPUT (for
		  packets generated by local processes)

OPTIONS
       The options that are recognized by ip6tables can be divided  into  sev‐
       eral different groups.

   COMMANDS
       These options specify the specific action to perform.  Only one of them
       can be specified on the command line unless otherwise specified	below.
       For  all the long versions of the command and option names, you need to
       use only enough letters to ensure that ip6tables can  differentiate  it
       from all other options.

       -A, --append chain rule-specification
	      Append one or more rules to the end of the selected chain.  When
	      the source and/or destination names resolve  to  more  than  one
	      address, a rule will be added for each possible address combina‐
	      tion.

       -D, --delete chain rule-specification
       -D, --delete chain rulenum
	      Delete one or more rules from the selected chain.	 There are two
	      versions	of this command: the rule can be specified as a number
	      in the chain (starting at 1 for the first rule)  or  a  rule  to
	      match.

       -I, --insert
	      Insert one or more rules in the selected chain as the given rule
	      number.  So, if the rule number is 1,  the  rule	or  rules  are
	      inserted	at the head of the chain.  This is also the default if
	      no rule number is specified.

       -R, --replace chain rulenum rule-specification
	      Replace a rule in the selected chain.  If the source and/or des‐
	      tination	names  resolve to multiple addresses, the command will
	      fail.  Rules are numbered starting at 1.

       -L, --list [chain]
	      List all rules in the selected chain.  If no chain is  selected,
	      all  chains  are	listed.	  As  every other iptables command, it
	      applies to the specified table (filter is the default), so  man‐
	      gle rules get listed by
	       ip6tables -t mangle -n -L
	      Please  note  that it is often used with the -n option, in order
	      to avoid long reverse DNS lookups.  It is legal to  specify  the
	      -Z  (zero)  option  as  well, in which case the chain(s) will be
	      atomically listed and zeroed.  The exact output is  affected  by
	      the  other arguments given. The exact rules are suppressed until
	      you use
	       ip6tables -L -v

       -F, --flush [chain]
	      Flush the selected chain (all the chains in the table if none is
	      given).	This  is  equivalent  to deleting all the rules one by
	      one.

       -Z, --zero [chain]
	      Zero the packet and byte counters in all chains.	It is legal to
	      specify  the  -L, --list (list) option as well, to see the coun‐
	      ters immediately before they are cleared. (See above.)

       -N, --new-chain chain
	      Create a new user-defined chain by the given name.   There  must
	      be no target of that name already.

       -X, --delete-chain [chain]
	      Delete the optional user-defined chain specified.	 There must be
	      no references to the chain.  If there are, you  must  delete  or
	      replace the referring rules before the chain can be deleted.  If
	      no argument is given, it	will  attempt  to  delete  every  non-
	      builtin chain in the table.

       -P, --policy chain target
	      Set  the policy for the chain to the given target.  See the sec‐
	      tion TARGETS for the legal targets.   Only  built-in  (non-user-
	      defined)	chains	can  have  policies,  and neither built-in nor
	      user-defined chains can be policy targets.

       -E, --rename-chain old-chain new-chain
	      Rename the user specified chain to the user supplied name.  This
	      is cosmetic, and has no effect on the structure of the table.

       -h     Help.   Give a (currently very brief) description of the command
	      syntax.

   PARAMETERS
       The following parameters make up a rule specification (as used  in  the
       add, delete, insert, replace and append commands).

       -p, --protocol [!] protocol
	      The  protocol of the rule or of the packet to check.  The speci‐
	      fied protocol can be one of tcp, udp, icmpv6, esp,  all,	or  it
	      can be a numeric value, representing one of these protocols or a
	      different one. A	protocol  name	from  /etc/protocols  is  also
	      allowed.	But IPv6 extension headers except esp are not allowed.
	      esp, and ipv6-nonext can be used with Kernel version  2.6.11  or
	      later.   A  "!"  argument	 before the protocol inverts the test.
	      The number zero is equivalent to all.  Protocol all  will	 match
	      with  all	 protocols and is taken as default when this option is
	      omitted.

       -s, --source [!] address[/mask]
	      Source specification.  Address can be either a hostname  (please
	      note that specifying any name to be resolved with a remote query
	      such as DNS is a really bad idea), a network IPv6 address	 (with
	      /mask),  or  a plain IPv6 address.  (the network name isn't sup‐
	      ported now).  The mask can be either a network mask or  a	 plain
	      number,  specifying  the	number	of 1's at the left side of the
	      network  mask.   Thus,  a	 mask	of   64	  is   equivalent   to
	      ffff:ffff:ffff:ffff:0000:0000:0000:0000.	 A "!" argument before
	      the address specification inverts the sense of the address.  The
	      flag --src is an alias for this option.

       -d, --destination [!] address[/mask]
	      Destination  specification.   See	 the  description  of  the  -s
	      (source) flag for a detailed description	of  the	 syntax.   The
	      flag --dst is an alias for this option.

       -j, --jump target
	      This  specifies  the target of the rule; i.e., what to do if the
	      packet matches it.  The  target  can  be	a  user-defined	 chain
	      (other than the one this rule is in), one of the special builtin
	      targets which decide the fate of the packet immediately,	or  an
	      extension	 (see EXTENSIONS below).  If this option is omitted in
	      a rule, then matching the	 rule  will  have  no  effect  on  the
	      packet's fate, but the counters on the rule will be incremented.

       -i, --in-interface [!] name
	      Name  of an interface via which a packet is going to be received
	      (only for packets entering the  INPUT,  FORWARD  and  PREROUTING
	      chains).	 When  the  "!"	 argument is used before the interface
	      name, the sense is inverted.  If the interface name  ends	 in  a
	      "+",  then any interface which begins with this name will match.
	      If this option is omitted, any interface name will match.

       -o, --out-interface [!] name
	      Name of an interface via which a packet is going to be sent (for
	      packets  entering	 the FORWARD and OUTPUT chains).  When the "!"
	      argument is  used	 before	 the  interface	 name,	the  sense  is
	      inverted.	  If the interface name ends in a "+", then any inter‐
	      face which begins with this name will match.  If this option  is
	      omitted, any interface name will match.

       -c, --set-counters  PKTS BYTES
	      This enables the administrator to initialize the packet and byte
	      counters of a rule (during INSERT, APPEND, REPLACE operations).

   OTHER OPTIONS
       The following additional options can be specified:

       -v, --verbose
	      Verbose output.  This option makes the  list  command  show  the
	      interface	 name,	the  rule options (if any), and the TOS masks.
	      The packet and byte counters are also listed,  with  the	suffix
	      'K',  'M' or 'G' for 1000, 1,000,000 and 1,000,000,000 multipli‐
	      ers respectively (but see the -x	flag  to  change  this).   For
	      appending,  insertion,  deletion	and  replacement,  this causes
	      detailed information on the rule or rules to be printed.

       -n, --numeric
	      Numeric output.  IP addresses and port numbers will  be  printed
	      in  numeric format.  By default, the program will try to display
	      them as host names, network names, or services (whenever	appli‐
	      cable).

       -x, --exact
	      Expand  numbers.	Display the exact value of the packet and byte
	      counters, instead of only the rounded number in  K's  (multiples
	      of  1000)	 M's (multiples of 1000K) or G's (multiples of 1000M).
	      This option is only relevant for the -L command.

       --line-numbers
	      When listing rules, add line numbers to the  beginning  of  each
	      rule, corresponding to that rule's position in the chain.

       --modprobe=command
	      When adding or inserting rules into a chain, use command to load
	      any necessary modules (targets, match extensions, etc).

MATCH EXTENSIONS
       ip6tables can use extended packet matching modules.  These  are	loaded
       in  two	ways:  implicitly, when -p or --protocol is specified, or with
       the -m or --match options, followed by the matching module name;	 after
       these,  various	extra command line options become available, depending
       on the specific module.	You can specify multiple extended  match  mod‐
       ules  in	 one  line, and you can use the -h or --help options after the
       module has been specified to receive help specific to that module.

       The following are included in the base package, and most of  these  can
       be preceded by a !  to invert the sense of the match.

   ah
       This  module  matches  the parameters in Authentication header of IPsec
       packets.

       --ahspi [!] spi[:spi]
	      Matches SPI.

       --ahlen [!] length
	      Total length of this header in octets.

       --ahres
	      Matches if the reserved field is filled with zero.

   condition
       This matches if a specific /proc filename is '0' or '1'.

       --condition [!] filename
	      Match on boolean value stored in	/proc/net/ip6t_condition/file‐
	      name file

   dst
       This module matches the parameters in Destination Options header

       --dst-len [!] length
	      Total length of this header in octets.

       --dst-opts type[:length][,type[:length]...]
	      numeric  type  of	 option	 and  the length of the option data in
	      octets.

   esp
       This module matches the SPIs in ESP header of IPsec packets.

       --espspi [!] spi[:spi]

   eui64
       This module matches the EUI-64 part of a stateless autoconfigured  IPv6
       address.	 It compares the EUI-64 derived from the source MAC address in
       Ehternet frame with the lower 64 bits of the IPv6 source	 address.  But
       "Universal/Local"  bit is not compared. This module doesn't match other
       link layer frame, and is only valid in the PREROUTING, INPUT  and  FOR‐
       WARD chains.

   frag
       This module matches the parameters in Fragment header.

       --fragid [!] id[:id]
	      Matches the given Identification or range of it.

       --fraglen [!] length
	      This  option cannot be used with kernel version 2.6.10 or later.
	      The length of Fragment header is static and this option  doesn't
	      make sense.

       --fragres
	      Matches if the reserved fields are filled with zero.

       --fragfirst
	      Matches on the first fragment.

       [--fragmore]
	      Matches if there are more fragments.

       [--fraglast]
	      Matches if this is the last fragement.

   fuzzy
       This  module  matches  a	 rate  limit based on a fuzzy logic controller
       [FLC]

       --lower-limit number
	      Specifies the lower limit (in packets per second).

       --upper-limit number
	      Specifies the upper limit (in packets per second).

   hbh
       This module matches the parameters in Hop-by-Hop Options header

       --hbh-len [!] length
	      Total length of this header in octets.

       --hbh-opts type[:length][,type[:length]...]
	      numeric type of option and the length  of	 the  option  data  in
	      octets.

   hl
       This module matches the Hop Limit field in the IPv6 header.

       --hl-eq [!] value
	      Matches if Hop Limit equals value.

       --hl-lt value
	      Matches if Hop Limit is less than value.

       --hl-gt value
	      Matches if Hop Limit is greater than value.

   icmpv6
       This  extension	is  loaded  if	`--protocol  ipv6-icmp' or `--protocol
       icmpv6' is specified. It provides the following option:

       --icmpv6-type [!] type[/code]|typename
	      This allows specification of the ICMPv6 type,  which  can	 be  a
	      numeric  ICMPv6  type,  type and code, or one of the ICMPv6 type
	      names shown by the command
	       ip6tables -p ipv6-icmp -h

   ipv6header
       This module matches IPv6 extension headers and/or upper layer header.

       --header [!] header[,header...]
	      Matches the packet which EXACTLY includes all specified headers.
	      The  headers  encapsulated  with	ESP  header  are out of scope.
	      header can be hop|hop-by-hop (Hop-by-Hop	Options	 header),  dst
	      (Destination  Options  header),  route  (Routing	header),  frag
	      (Fragment header), auth (Authentication header),	esp  (Encapsu‐
	      lating  Security	Payload	 header),  none (No Next header) which
	      matches 59 in the 'Next Header field' of IPv6 header or any IPv6
	      extension headers, or proto which matches any upper layer proto‐
	      col header. A protocol  name  from  /etc/protocols  and  numeric
	      value also allowed. The number 255 is equivalent to proto.

       [--soft]
	      Matches  if  the	packet	includes  all  specified  headers with
	      --header, AT LEAST.

   length
       This module matches the length of the IPv6 payload in octets, or	 range
       of it.  IPv6 header itself isn't counted.

       --length [!] length[:length]

   limit
       This  module  matches at a limited rate using a token bucket filter.  A
       rule using this extension  will	match  until  this  limit  is  reached
       (unless	the `!' flag is used).	It can be used in combination with the
       LOG target to give limited logging, for example.

       --limit rate
	      Maximum average matching rate: specified as a  number,  with  an
	      optional	`/second',  `/minute',	`/hour', or `/day' suffix; the
	      default is 3/hour.

       --limit-burst number
	      Maximum initial number of packets to  match:  this  number  gets
	      recharged	 by  one  every	 time the limit specified above is not
	      reached, up to this number; the default is 5.

   mac
       --mac-source [!] address
	      Match  source  MAC  address.    It   must	  be   of   the	  form
	      XX:XX:XX:XX:XX:XX.   Note that this only makes sense for packets
	      coming from an Ethernet device and entering the PREROUTING, FOR‐
	      WARD or INPUT chains.

   mark
       This  module  matches the netfilter mark field associated with a packet
       (which can be set using the MARK target below).

       --mark value[/mask]
	      Matches packets with the given unsigned mark value (if a mask is
	      specified, this is logically ANDed with the mask before the com‐
	      parison).

   multiport
       This module matches a set of source or destination  ports.   Up	to  15
       ports  can be specified.	 A port range (port:port) counts as two ports,
       but range isn't supported now. It can only be used in conjunction  with
       -p tcp or -p udp.

       --source-ports [!] port[,port[,port:port...]]
	      Match  if	 the  source port is one of the given ports.  The flag
	      --sports is a convenient alias for this option.

       --destination-ports [!] port[,port[,port:port...]]
	      Match if the destination port is one of the  given  ports.   The
	      flag --dports is a convenient alias for this option.

       --ports [!] port[,port[,port:port...]]
	      Match  if the both the source and destination ports are equal to
	      each other and to one of the given ports.

   nth
       This module matches every `n'th packet

       --every value
	      Match every `value' packet

       [--counter num]
	      Use internal counter number `num'.  Default is `0'.

       [--start num]
	      Initialize the counter at the number `num' insetad of `0'.  Most
	      between `0' and `value'-1.

       [--packet num]
	      Match on `num' packet.  Most be between `0' and `value'-1.

   owner
       This  module  attempts  to  match various characteristics of the packet
       creator, for locally-generated packets.	It is only valid in the OUTPUT
       chain,  and  even this some packets (such as ICMPv6 ping responses) may
       have no owner, and hence never match.  This is regarded	as  experimen‐
       tal.

       --uid-owner userid
	      Matches  if  the	packet was created by a process with the given
	      effective user id.

       --gid-owner groupid
	      Matches if the packet was created by a process  with  the	 given
	      effective group id.

       --pid-owner processid
	      Matches  if  the	packet was created by a process with the given
	      process id.

       --sid-owner sessionid
	      Matches if the packet was created by a process in the given ses‐
	      sion group.

       NOTE: pid, sid and command matching are broken on SMP

   physdev
       This  module  matches  on  the  bridge  port  input  and output devices
       enslaved to a bridge device. This module is a part of  the  infrastruc‐
       ture that enables a transparent bridging IP firewall and is only useful
       for kernel versions above version 2.5.44.

       --physdev-in [!] name
	      Name of a bridge port via which a packet is received  (only  for
	      packets  entering	 the INPUT, FORWARD and PREROUTING chains). If
	      the interface name ends in  a  "+",  then	 any  interface	 which
	      begins  with  this  name will match. If the packet didn't arrive
	      through a bridge device, this packet won't  match	 this  option,
	      unless '!' is used.

       --physdev-out [!] name
	      Name  of	a  bridge  port via which a packet is going to be sent
	      (for  packets  entering  the  FORWARD,  OUTPUT  and  POSTROUTING
	      chains).	 If  the interface name ends in a "+", then any inter‐
	      face which begins with this name will match. Note	 that  in  the
	      nat and mangle OUTPUT chains one cannot match on the bridge out‐
	      put port, however one can in the filter  OUTPUT  chain.  If  the
	      packet  won't leave by a bridge device or it is yet unknown what
	      the output device will be, then  the  packet  won't  match  this
	      option, unless

       [!] --physdev-is-in
	      Matches if the packet has entered through a bridge interface.

       [!] --physdev-is-out
	      Matches if the packet will leave through a bridge interface.

       [!] --physdev-is-bridged
	      Matches  if  the	packet	is  being bridged and therefore is not
	      being routed.  This is only useful in the FORWARD and  POSTROUT‐
	      ING chains.

   policy
       This modules matches the policy used by IPsec for handling a packet.

       --dir in|out
	      Used  to	select whether to match the policy used for decapsula‐
	      tion or the policy that will be used for encapsulation.	in  is
	      valid  in the PREROUTING, INPUT and FORWARD chains, out is valid
	      in the POSTROUTING, OUTPUT and FORWARD chains.

       --pol none|ipsec
	      Matches if the packet is subject to IPsec processing.

       --strict
	      Selects whether to match the exact policy or match if  any  rule
	      of the policy matches the given policy.

       --reqid id
	      Matches the reqid of the policy rule. The reqid can be specified
	      with setkey(8) using unique:id as level.

       --spi spi
	      Matches the SPI of the SA.

       --proto ah|esp|ipcomp
	      Matches the encapsulation protocol.

       --mode tunnel|transport
	      Matches the encapsulation mode.

       --tunnel-src addr[/mask]
	      Matches the source end-point address of a tunnel mode SA.	  Only
	      valid with --mode tunnel.

       --tunnel-dst addr[/mask]
	      Matches  the  destination end-point address of a tunnel mode SA.
	      Only valid with --mode tunnel.

       --next Start the next element in the policy specification. Can only  be
	      used with --strict

   random
       This module randomly matches a certain percentage of all packets.

       --average percent
	      Matches  the given percentage.  If omitted, a probability of 50%
	      is set.

   rt
       Match on IPv6 routing header

       --rt-type [!] type
	      Match the type (numeric).

       --rt-segsleft [!] num[:num]
	      Match the `segments left' field (range).

       --rt-len [!] length
	      Match the length of this header.

       --rt-0-res
	      Match the reserved field, too (type=0)

       --rt-0-addrs ADDR[,ADDR...]
	      Match type=0 addresses (list).

       --rt-0-not-strict
	      List of type=0 addresses is not a strict list.

   tcp
       These extensions are loaded if `--protocol tcp' is specified.  It  pro‐
       vides the following options:

       --source-port [!] port[:port]
	      Source  port  or	port range specification. This can either be a
	      service name or a port number. An inclusive range	 can  also  be
	      specified,  using	 the  format  port:port.  If the first port is
	      omitted, "0" is assumed; if the  last  is	 omitted,  "65535"  is
	      assumed.	If the second port greater then the first they will be
	      swapped.	The flag  --sport  is  a  convenient  alias  for  this
	      option.

       --destination-port [!] port[:port]
	      Destination  port or port range specification.  The flag --dport
	      is a convenient alias for this option.

       --tcp-flags [!] mask comp
	      Match when the TCP flags are as specified.  The  first  argument
	      is  the  flags which we should examine, written as a comma-sepa‐
	      rated list, and the second argument is a comma-separated list of
	      flags which must be set.	Flags are: SYN ACK FIN RST URG PSH ALL
	      NONE.  Hence the command
	       ip6tables -A FORWARD -p tcp --tcp-flags SYN,ACK,FIN,RST SYN
	      will only match packets with the SYN flag set, and the ACK,  FIN
	      and RST flags unset.

       [!] --syn
	      Only  match TCP packets with the SYN bit set and the ACK and RST
	      bits cleared.  Such packets are used to request  TCP  connection
	      initiation;  for	example,  blocking  such  packets coming in an
	      interface will prevent incoming TCP  connections,	 but  outgoing
	      TCP  connections will be unaffected.  It is equivalent to --tcp-
	      flags SYN,RST,ACK SYN.  If the "!" flag  precedes	 the  "--syn",
	      the sense of the option is inverted.

       --tcp-option [!] number
	      Match if TCP option set.

   udp
       These  extensions are loaded if `--protocol udp' is specified.  It pro‐
       vides the following options:

       --source-port [!] port[:port]
	      Source port or port range specification.	See the description of
	      the --source-port option of the TCP extension for details.

       --destination-port [!] port[:port]
	      Destination  port or port range specification.  See the descrip‐
	      tion of the --destination-port option of the TCP	extension  for
	      details.

TARGET EXTENSIONS
       ip6tables  can  use extended target modules: the following are included
       in the standard distribution.

   HL
       This is used to modify the Hop Limit field  in  IPv6  header.  The  Hop
       Limit  field is similar to what is known as TTL value in IPv4.  Setting
       or incrementing the Hop Limit field can potentially be very  dangerous,
       so  it should be avoided at any cost. This target is only valid in man‐
       gle table.

       Don't ever set or increment the value on packets that leave your	 local
       network!

       --hl-set value
	      Set the Hop Limit to `value'.

       --hl-dec value
	      Decrement the Hop Limit `value' times.

       --hl-inc value
	      Increment the Hop Limit `value' times.

   LOG
       Turn  on	 kernel	 logging of matching packets.  When this option is set
       for a rule, the Linux kernel will print some information on all	match‐
       ing  packets  (like  most  IPv6	IPv6-header fields) via the kernel log
       (where it can be read with dmesg or syslogd(8)).	 This is a "non-termi‐
       nating  target", i.e. rule traversal continues at the next rule.	 So if
       you want to LOG the packets you refuse, use two separate rules with the
       same matching criteria, first using target LOG then DROP (or REJECT).

       --log-level level
	      Level of logging (numeric or see syslog.conf(5)).

       --log-prefix prefix
	      Prefix  log messages with the specified prefix; up to 29 letters
	      long, and useful for distinguishing messages in the logs.

       --log-tcp-sequence
	      Log TCP sequence numbers. This is a security risk if the log  is
	      readable by users.

       --log-tcp-options
	      Log options from the TCP packet header.

       --log-ip-options
	      Log options from the IPv6 packet header.

       --log-uid
	      Log the userid of the process which generated the packet.

   MARK
       This  is	 used  to  set	the  netfilter	mark value associated with the
       packet.	It is only valid in the mangle table.

       --set-mark mark

   NFQUEUE
       This target is an extension of the QUEUE target. As opposed  to	QUEUE,
       it  allows  you	to put a packet into any specific queue, identified by
       its 16-bit queue number.

       --queue-num value
	      This specifies the QUEUE number to use. Valud queue numbers  are
	      0 to 65535. The default value is 0.

       It  can	only  be  used	with Kernel versions 2.6.14 or later, since it
       requires
	      the nfnetlink_queue kernel support.

   REJECT
       This is used to send back an error packet in response  to  the  matched
       packet:	otherwise it is equivalent to DROP so it is a terminating TAR‐
       GET, ending rule traversal.  This target is only valid  in  the	INPUT,
       FORWARD	and  OUTPUT  chains,  and  user-defined	 chains which are only
       called from those chains.  The following option controls the nature  of
       the error packet returned:

       --reject-with type
	      The type given can be
	       icmp6-no-route
	       no-route
	       icmp6-adm-prohibited
	       adm-prohibited
	       icmp6-addr-unreachable
	       addr-unreach
	       icmp6-port-unreachable
	       port-unreach
	      which  return the appropriate ICMPv6 error message (port-unreach
	      is the default). Finally, the option tcp-reset can  be  used  on
	      rules  which  only match the TCP protocol: this causes a TCP RST
	      packet to be sent back.  This  is	 mainly	 useful	 for  blocking
	      ident  (113/tcp) probes which frequently occur when sending mail
	      to broken mail hosts (which won't accept your  mail  otherwise).
	      tcp-reset	 can  only be used with kernel versions 2.6.14 or lat‐
	      ter.

   ROUTE
       This is used to explicitly override the core  network  stack's  routing
       decision.  mangle table.

       --oif ifname
	      Route the packet through `ifname' network interface

       --gw IPv6_address
	      Route the packet via this gateway

       --continue
	      Behave like a non-terminating target and continue traversing the
	      rules. Not valid in combination with `--tee'

       --tee  Make a copy of the packet, and route that copy to the given des‐
	      tination.	 For the original, uncopied packet, behave like a non-
	      terminating target and continue traversing the rules.  Not valid
	      in combination with `--continue'

   TRACE
       This  target  has  no options.  It just turns on packet tracing for all
       packets that match this rule.

DIAGNOSTICS
       Various error messages are printed to standard error.  The exit code is
       0 for correct functioning.  Errors which appear to be caused by invalid
       or abused command line parameters cause an exit code of	2,  and	 other
       errors cause an exit code of 1.

BUGS
       Bugs?   What's  this?  ;-)  Well...  the	 counters  are not reliable on
       sparc64.

COMPATIBILITY WITH IPCHAINS
       This ip6tables is very similar to ipchains by Rusty Russell.  The  main
       difference  is  that the chains INPUT and OUTPUT are only traversed for
       packets coming into the local host and originating from the local  host
       respectively.   Hence every packet only passes through one of the three
       chains (except loopback traffic, which involves both INPUT  and	OUTPUT
       chains); previously a forwarded packet would pass through all three.

       The  other main difference is that -i refers to the input interface; -o
       refers to the output interface, and  both  are  available  for  packets
       entering	 the  FORWARD  chain.	There  are  several  other  changes in
       ip6tables.

SEE ALSO
       ip6tables-save(8), ip6tables-restore(8), iptables(8), iptables-save(8),
       iptables-restore(8), libipq(3).

       The packet-filtering-HOWTO details iptables usage for packet filtering,
       the NAT-HOWTO details NAT, the netfilter-extensions-HOWTO  details  the
       extensions  that	 are not in the standard distribution, and the netfil‐
       ter-hacking-HOWTO details the netfilter internals.
       See http://www.netfilter.org/.

AUTHORS
       Rusty Russell wrote iptables, in early consultation with Michael	 Neul‐
       ing.

       Marc  Boucher  made  Rusty  abandon  ipnatctl by lobbying for a generic
       packet selection framework in iptables, then wrote  the	mangle	table,
       the owner match, the mark stuff, and ran around doing cool stuff every‐
       where.

       James Morris wrote the TOS target, and tos match.

       Jozsef Kadlecsik wrote the REJECT target.

       Harald Welte wrote the ULOG and NFQUEUE target, the new libiptc, aswell
       as TTL match+target and libipulog.

       The  Netfilter  Core  Team  is:	Marc Boucher, Martin Josefsson, Jozsef
       Kadlecsik, James Morris, Harald Welte and Rusty Russell.

       ip6tables man page created by Andras Kis-Szabo, based on	 iptables  man
       page written by Herve Eychenne <rv@wallfire.org>.

				 Jan 22, 2006			  IP6TABLES(8)
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