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SETKEY(8)                   System Manager's Manual                  SETKEY(8)

     setkey - manually manipulate the IPsec SA/SP database

     setkey [-knrv] file ...
     setkey [-knrv] -c
     setkey [-krv] -f filename
     setkey [-aklPrv] -D
     setkey [-Pvp] -F
     setkey [-H] -x
     setkey [-?V]

     setkey adds, updates, dumps, or flushes Security Association Database
     (SAD) entries as well as Security Policy Database (SPD) entries in the

     setkey takes a series of operations from standard input (if invoked with
     -c) or the file named filename (if invoked with -f filename).

     (no flag)
             Dump the SAD entries or SPD entries contained in the specified

     -?      Print short help.

     -a      setkey usually does not display dead SAD entries with -D.  If -a
             is also specified, the dead SAD entries will be displayed as
             well.  A dead SAD entry is one that has expired but remains in
             the system because it is referenced by some SPD entries.

     -D      Dump the SAD entries.  If -P is also specified, the SPD entries
             are dumped.  If -p is specified, the ports are displayed.

     -F      Flush the SAD entries.  If -P is also specified, the SPD entries
             are flushed.

     -H      Add hexadecimal dump in -x mode.

     -h      On NetBSD, synonym for -H.  On other systems, synonym for -?.

     -k      Use semantics used in kernel.  Available only in Linux.  See also

     -l      Loop forever with short output on -D.

     -n      No action.  The program will check validity of the input, but no
             changes to the SPD will be made.

     -r      Use semantics described in IPsec RFCs.  This mode is default.
             For details see section RFC vs Linux kernel semantics.  Available
             only in Linux.  See also -k.

     -x      Loop forever and dump all the messages transmitted to the PF_KEY
             socket.  -xx prints the unformatted timestamps.

     -V      Print version string.

     -v      Be verbose.  The program will dump messages exchanged on the
             PF_KEY socket, including messages sent from other processes to
             the kernel.

   Configuration syntax
     With -c or -f on the command line, setkey accepts the following
     configuration syntax.  Lines starting with hash signs (`#') are treated
     as comment lines.

     add [-46n] src dst protocol spi [extensions] algorithm ...;
             Add an SAD entry.  add can fail for multiple reasons, including
             when the key length does not match the specified algorithm.

     getspi [-46n] src dst protocol spi [extensions];
             Add a larval SAD entry.  If spi is not zero, tell the kernel use
             the SPI as-is.  Otherwise, the kernel picks a random SPI.

     update [-46n] src dst protocol spi [extensions] algorithm ...;
             Update an existing SAD entry.  It must be used together with add
             or getspi in a series of operations because the API requires that
             a process updating an SAD entry is the same as one created the
             SAD entry.

     get [-46n] src dst protocol spi;
             Show an SAD entry.

     delete [-46n] src dst protocol spi;
             Remove an SAD entry.

     deleteall [-46n] src dst protocol;
             Remove all SAD entries that match the specification.

     flush [protocol];
             Clear all SAD entries matched by the options.  -F on the command
             line achieves the same functionality.

     dump [protocol];
             Dumps all SAD entries matched by the options.  -D on the command
             line achieves the same functionality.

     spdadd [-46n] src_range dst_range upperspec label policy;
             Add an SPD entry.

     spdadd tagged tag policy;
             Add an SPD entry based on a PF tag.  tag must be a string
             surrounded by double quotes.

     spdupdate [-46n] src_range dst_range upperspec label policy;
             Updates an SPD entry.

     spdupdate tagged tag policy;
             Update an SPD entry based on a PF tag.  tag must be a string
             surrounded by double quotes.

     spddelete [-46n] src_range dst_range upperspec -P direction;
             Delete an SPD entry.

             Clear all SPD entries.  -FP on the command line achieves the same

             Dumps all SPD entries.  -DP on the command line achieves the same

     Meta-arguments are as follows:

     dst     Source/destination of the secure communication is specified as an
             IPv4/v6 address, and an optional port number between square
             brackets.  setkey can resolve a FQDN into numeric addresses.  If
             the FQDN resolves into multiple addresses, setkey will install
             multiple SAD/SPD entries into the kernel by trying all possible
             combinations.  -4, -6, and -n restrict the address resolution of
             FQDN in certain ways.  -4 and -6 restrict results into IPv4/v6
             addresses only, respectively.  -n avoids FQDN resolution and
             requires addresses to be numeric addresses.

             protocol is one of following:
             esp         ESP based on rfc2406
             esp-old     ESP based on rfc1827
             esp-udp     UDP encapsulated ESP for NAT traversal (rfc3948)
             ah          AH based on rfc2402
             ah-old      AH based on rfc1826
             ipcomp      IPComp
             tcp         TCP-MD5 based on rfc2385

     spi     Security Parameter Index (SPI) for the SAD and the SPD.  spi must
             be a decimal number, or a hexadecimal number with a "0x" prefix.
             SPI values between 0 and 255 are reserved for future use by IANA
             and cannot be used.  TCP-MD5 associations must use 0x1000 and
             therefore only have per-host granularity at this time.

             take some of the following:
             -m mode     Specify a security protocol mode for use.  mode is
                         one of following: transport, tunnel, or any.  The
                         default value is any.
             -r size     Specify window size of bytes for replay prevention.
                         size must be decimal number in 32-bit word.  If size
                         is zero or not specified, replay checks don't take
             -u id       Specify the identifier of the policy entry in the
                         SPD.  See policy.
             -f pad_option
                         defines the content of the ESP padding.  pad_option
                         is one of following:
                         zero-pad    All the paddings are zero.
                         random-pad  A series of randomized values are used.
                         seq-pad     A series of sequential increasing numbers
                                     started from 1 are used.
             -f nocyclic-seq
                         Don't allow cyclic sequence numbers.
             -lh time
             -ls time    Specify hard/soft life time duration of the SA
                         measured in seconds.
             -bh bytes
             -bs bytes   Specify hard/soft life time duration of the SA
                         measured in bytes transported.
             -esp_frag bytes
                         Specify esp fragment size for NAT-T (only valid for
                         NAT-T SAs).
             -ctx doi algorithm context-name
                         Specify an access control label.  The access control
                         label is interpreted by the LSM (e.g., SELinux).
                         Ultimately, it enables MAC on network communications.
                         doi         The domain of interpretation, which is
                                     used by the IKE daemon to identify the
                                     domain in which negotiation takes place.
                         algorithm   Indicates the LSM for which the label is
                                     generated (e.g., SELinux).
                                     The string representation of the label
                                     that is interpreted by the LSM.

             -E ealgo key
                         Specify an encryption algorithm ealgo for ESP.
             -E ealgo key -A aalgo key
                         Specify an encryption algorithm ealgo, as well as a
                         payload authentication algorithm aalgo, for ESP.
             -A aalgo key
                         Specify an authentication algorithm for AH.
             -C calgo [-R]
                         Specify a compression algorithm for IPComp.  If -R is
                         specified, the spi field value will be used as the
                         IPComp CPI (compression parameter index) on wire as-
                         is.  If -R is not specified, the kernel will use
                         well-known CPI on wire, and spi field will be used
                         only as an index for kernel internal usage.

             key must be a double-quoted character string, or a series of
             hexadecimal digits preceded by "0x".

             Possible values for ealgo, aalgo, and calgo are specified in the
             Algorithms sections.

             These select the communications that should be secured by IPsec.
             They can be an IPv4/v6 address or an IPv4/v6 address range, and
             may be accompanied by a TCP/UDP port specification.  This takes
             the following form:


             prefixlen and port must be decimal numbers.  The square brackets
             around port are really necessary, they are not man page meta-
             characters.  For FQDN resolution, the rules applicable to src and
             dst apply here as well.

             Upper-layer protocol to be used.  You can use one of the words in
             /etc/protocols as upperspec, or icmp6, ip4, gre, or any.  any
             stands for "any protocol".  You can also use the protocol number.
             Additional specification can be placed after the protocol name
             for some protocols.  You can specify a type and/or a code of ICMP
             or ICMPv6.  The type is separated from a code by single comma and
             the code must always be specified.  GRE key can be specified in
             dotted-quad format or as plain number.  When a zero is specified,
             the kernel deals with it as a wildcard.  Note that the kernel can
             not distinguish a wildcard from an ICPMv6 type of zero.

             For example, the following means that the policy doesn't require
             IPsec for any inbound Neighbor Solicitation.
                   spdadd ::/0 ::/0 icmp6 135,0 -P in none;

             A second example of requiring transport mode encryption of
             specific GRE tunnel:
                   spdadd gre 1234 ipsec

             Note: upperspec does not work against forwarding case at this
             moment, as it requires extra reassembly at the forwarding node
             (not implemented at this moment).  There are many protocols in
             /etc/protocols, but all protocols except of TCP, UDP, GRE, and
             ICMP may not be suitable to use with IPsec.  You have to consider
             carefully what to use.

     label   label is the access control label for the policy.  This label is
             interpreted by the LSM (e.g., SELinux).  Ultimately, it enables
             MAC on network communications.  When a policy contains an access
             control label, SAs negotiated with this policy will contain the
             label.  Its format:
             -ctx doi algorithm context-name
                         doi         The domain of interpretation, which is
                                     used by the IKE daemon to identify the
                                     domain in which negotiation takes place.
                         algorithm   Indicates the LSM for which the label is
                                     generated (e.g., SELinux).
                                     The string representation of the label
                                     that is interpreted by the LSM.

     policy  policy is in one of the following three formats:
             -P direction [priority specification] discard
             -P direction [priority specification] none
             -P direction [priority specification] ipsec
             protocol/mode/src-dst/level [...]

             You must specify the direction of its policy as direction.
             Either out, in, or fwd can be used.

             priority specification is used to control the placement of the
             policy within the SPD.  Policy position is determined by a signed
             integer where higher priorities indicate the policy is placed
             closer to the beginning of the list and lower priorities indicate
             the policy is placed closer to the end of the list.  Policies
             with equal priorities are added at the end of groups of such

             Priority can only be specified when setkey has been compiled
             against kernel headers that support policy priorities (Linux >=
             2.6.6).  If the kernel does not support priorities, a warning
             message will be printed the first time a priority specification
             is used.  Policy priority takes one of the following formats:

             {priority,prio} offset
                      offset is an integer in the range from -2147483647 to

             {priority,prio} base {+,-} offset
                      base is either low (-1073741824), def (0), or high

                      offset is an unsigned integer.  It can be up to
                      1073741824 for positive offsets, and up to 1073741823
                      for negative offsets.

             discard means the packet matching indexes will be discarded.
             none means that IPsec operation will not take place onto the
             packet.  ipsec means that IPsec operation will take place onto
             the packet.

             The protocol/mode/src-dst/level part specifies the rule how to
             process the packet.  Either ah, esp, or ipcomp must be used as
             protocol.  mode is either transport or tunnel.  If mode is
             tunnel, you must specify the end-point addresses of the SA as src
             and dst with `-' between these addresses, which is used to
             specify the SA to use.  If mode is transport, both src and dst
             can be omitted.  level is to be one of the following: default,
             use, require, or unique.  If the SA is not available in every
             level, the kernel will ask the key exchange daemon to establish a
             suitable SA.  default means the kernel consults the system wide
             default for the protocol you specified, e.g. the esp_trans_deflev
             sysctl variable, when the kernel processes the packet.  use means
             that the kernel uses an SA if it's available, otherwise the
             kernel keeps normal operation.  require means SA is required
             whenever the kernel sends a packet matched with the policy.
             unique is the same as require; in addition, it allows the policy
             to match the unique out-bound SA.  You just specify the policy
             level unique, racoon(8) will configure the SA for the policy.  If
             you configure the SA by manual keying for that policy, you can
             put a decimal number as the policy identifier after unique
             separated by a colon `:' like: unique:number in order to bind
             this policy to the SA.  number must be between 1 and 32767.  It
             corresponds to extensions -u of the manual SA configuration.
             When you want to use SA bundle, you can define multiple rules.
             For example, if an IP header was followed by an AH header
             followed by an ESP header followed by an upper layer protocol
             header, the rule would be:
                   esp/transport//require ah/transport//require;
             The rule order is very important.

             When NAT-T is enabled in the kernel, policy matching for ESP over
             UDP packets may be done on endpoint addresses and port (this
             depends on the system.  System that do not perform the port check
             cannot support multiple endpoints behind the same NAT).  When
             using ESP over UDP, you can specify port numbers in the endpoint
             addresses to get the correct matching.  Here is an example:

                 spdadd[any][any] any -P out ipsec
                     esp/tunnel/[4500]-[30000]/require ;

             These ports must be left unspecified (which defaults to 0) for
             anything other than ESP over UDP.  They can be displayed in SPD
             dump using setkey -DPp.

             Note that discard and none are not in the syntax described in
             ipsec_set_policy(3).  There are a few differences in the syntax.
             See ipsec_set_policy(3) for detail.

     The following list shows the supported algorithms.  protocol and
     algorithm are almost orthogonal.  These authentication algorithms can be
     used as aalgo in -A aalgo of the protocol parameter:

           algorithm       keylen (bits)
           hmac-md5        128             ah: rfc2403
                           128             ah-old: rfc2085
           hmac-sha1       160             ah: rfc2404
                           160             ah-old: 128bit ICV (no document)
           keyed-md5       128             ah: 96bit ICV (no document)
                           128             ah-old: rfc1828
           keyed-sha1      160             ah: 96bit ICV (no document)
                           160             ah-old: 128bit ICV (no document)
           null            0 to 2048       for debugging
           hmac-sha256     256             ah: 128bit ICV (RFC4868)
                           256             ah-old: 128bit ICV (no document)
           hmac-sha384     384             ah: 192bit ICV (RFC4868)
                           384             ah-old: 128bit ICV (no document)
           hmac-sha512     512             ah: 256bit ICV (RFC4868)
                           512             ah-old: 128bit ICV (no document)
           hmac-ripemd160  160             ah: 96bit ICV (RFC2857)
                                           ah-old: 128bit ICV (no document)
           aes-xcbc-mac    128             ah: 96bit ICV (RFC3566)
                           128             ah-old: 128bit ICV (no document)
           tcp-md5         8 to 640        tcp: rfc2385

     These encryption algorithms can be used as ealgo in -E ealgo of the
     protocol parameter:

           algorithm       keylen (bits)
           des-cbc         64              esp-old: rfc1829, esp: rfc2405
           3des-cbc        192             rfc2451
           null            0 to 2048       rfc2410
           blowfish-cbc    40 to 448       rfc2451
           cast128-cbc     40 to 128       rfc2451
           des-deriv       64              ipsec-ciph-des-derived-01
           3des-deriv      192             no document
           rijndael-cbc    128/192/256     rfc3602
           twofish-cbc     0 to 256        draft-ietf-ipsec-ciph-aes-cbc-01
           aes-ctr         160/224/288     rfc3686
           camellia-cbc    128/192/256     rfc4312
           aes-gcm-16      160/224/288     rfc4106
           aes-gmac        160/224/288     rfc4543

     Note that the first 128/192/256 bits of a key for aes-ctr, aes-gcm-16 or
     aes-gmac will be used as AES key, and the remaining 32 bits will be used
     as nonce.  Also note that aes-gmac does not encrypt the payload, it only
     provides authentication.

     These compression algorithms can be used as calgo in -C calgo of the
     protocol parameter:

           deflate         rfc2394

   RFC vs Linux kernel semantics
     The Linux kernel uses the fwd policy instead of the in policy for packets
     what are forwarded through that particular box.

     In kernel mode, setkey manages and shows policies and SAs exactly as they
     are stored in the kernel.

     In RFC mode, setkey

     creates fwd policies for every in policy inserted

     (not implemented yet) filters out all fwd policies

     The setkey utility exits 0 on success, and >0 if an error occurs.

         add 3ffe:501:4819::1 3ffe:501:481d::1 esp 123457
                 -E des-cbc 0x3ffe05014819ffff ;

         add -6 myhost.example.com yourhost.example.com ah 123456
                 -A hmac-sha1 "AH SA configuration!" ;

         add esp 0x10001
                 -E des-cbc 0x3ffe05014819ffff
                 -A hmac-md5 "authentication!!" ;

         get 3ffe:501:4819::1 3ffe:501:481d::1 ah 123456 ;

         flush ;

         dump esp ;

         spdadd[21][any] any
                 -P out ipsec esp/tunnel/ ;

         add tcp 0x1000 -A tcp-md5 "TCP-MD5 BGP secret" ;

         add esp 0x10001
                 -ctx 1 1 "system_u:system_r:unconfined_t:SystemLow-SystemHigh"
                 -E des-cbc 0x3ffe05014819ffff;

         spdadd any
                 -ctx 1 1 "system_u:system_r:unconfined_t:SystemLow-SystemHigh"
                 -P out ipsec esp/transport//require ;

     ipsec_set_policy(3), racoon(8), sysctl(8)

     Changed manual key configuration for IPsec,
     http://www.kame.net/newsletter/19991007/, October 1999.

     The setkey command first appeared in the WIDE Hydrangea IPv6 protocol
     stack kit.  The command was completely re-designed in June 1998.

     setkey should report and handle syntax errors better.

     For IPsec gateway configuration, src_range and dst_range with TCP/UDP
     port numbers does not work, as the gateway does not reassemble packets
     (it cannot inspect upper-layer headers).

NetBSD 9.99                      July 23, 2019                     NetBSD 9.99