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       ipsec_spi - list IPSEC Security Associations


       ipsec spi


       Note that eroute is only supported on the classic KLIPS stack. It is
       not supported on any other stack and will be completely removed in
       future versions. A replacement command still needs to be designed


       /proc/net/ipsec_spi is a read-only file that lists the current IPSEC
       Security Associations. A Security Association (SA) is a transform
       through which packet contents are to be processed before being
       forwarded. A transform can be an IPv4-in-IPv4 or IPv6-in-IPv6
       encapsulation, an IPSEC Authentication Header (authentication with no
       encryption), or an IPSEC Encapsulation Security Payload (encryption,
       possibly including authentication).

       When a packet is passed from a higher networking layer through an IPSEC
       virtual interface, a search in the extended routing table (see
       ipsec_eroute(5)) yields a IP protocol number , a Security Parameters
       Index (SPI) and an effective destination address When an IPSEC packet
       arrives from the network, its ostensible destination, an SPI and an IP
       protocol specified by its outermost IPSEC header are used. The
       destination/SPI/protocol combination is used to select a relevant SA.
       (See ipsec_spigrp(5) for discussion of how multiple transforms are

       An spi , proto, daddr and address_family arguments specify an SAID.
       Proto is an ASCII string, "ah", "esp", "comp" or "tun", specifying the
       IP protocol.  Spi is a number, preceded by ´.´ indicating hexadecimal
       and IPv4 or by ´:´ indicating hexadecimal and IPv6, where each
       hexadecimal digit represents 4 bits, between 0x100 and 0xffffffff;
       values from 0x0 to 0xff are reserved.  Daddr is a dotted-decimal IPv4
       destination address or a coloned hex IPv6 destination address.

       An SAID combines the three parameters above, such as: "tun.101@"
       for IPv4 or "tun:101@3049:1::1" for IPv6

       A table entry consists of:


           <transform name (proto,encalg,authalg)>:

           direction (dir=)

           source address (src=)

           source and destination addresses and masks for inner header policy
           check addresses (policy=), as dotted-quads or coloned hex,
           separated by ´->´, for IPv4-in-IPv4 or IPv6-in-IPv6 SAs only

           initialisation vector length and value (iv_bits=, iv=) if non-zero

           out-of-order window size, number of out-of-order errors, sequence
           number, recently received packet bitmask, maximum difference
           between sequence numbers (ooowin=, ooo_errs=, seq=, bit=,
           max_seq_diff=) if SA is AH or ESP and if individual items are

           extra flags (flags=) if any are set

           authenticator length in bits (alen=) if non-zero

           authentication key length in bits (aklen=) if non-zero

           authentication errors (auth_errs=) if non-zero

           encryption key length in bits (eklen=) if non-zero

           encryption size errors (encr_size_errs=) if non-zero

           encryption padding error warnings (encr_pad_errs=) if non-zero

           lifetimes legend, c=Current status, s=Soft limit when exceeded will
           initiate rekeying, h=Hard limit will cause termination of SA

           number of connections to which the SA is allocated (c), that will
           cause a rekey (s), that will cause an expiry (h) (alloc=), if any
           value is non-zero

           number of bytes processesd by this SA (c), that will cause a rekey
           (s), that will cause an expiry (h) (bytes=), if any value is

           time since the SA was added (c), until rekey (s), until expiry (h),
           in seconds (add=)

           time since the SA was first used (c), until rekey (s), until expiry
           (h), in seconds (used=), if any value is non-zero

           number of packets processesd by this SA (c), that will cause a
           rekey (s), that will cause an expiry (h) (packets=), if any value
           is non-zero

           time since the last packet was processed, in seconds (idle=), if SA
           has been used

           average compression ratio (ratio=)


       tun.12a@ IPIP: dir=out src=




       is an outbound IPv4-in-IPv4 (protocol 4) tunnel-mode SA set up between
       machines and with an SPI of 12a in
       hexadecimal that has passed about 14 kilobytes of traffic in 14 packets
       since it was created, 269 seconds ago, first used 149 seconds ago and
       has been idle for 23 seconds.

       esp:9a35fc02@3049:1::1 ESP_3DES_HMAC_MD5:

        dir=in src=9a35fc02@3049:1::2

        ooowin=32 seq=7149 bit=0xffffffff

        alen=128 aklen=128 eklen=192




       is an inbound Encapsulating Security Payload (protocol 50) SA on
       machine 3049:1::1 with an SPI of 9a35fc02 that uses 3DES as the
       encryption cipher, HMAC MD5 as the authentication algorithm, an
       out-of-order window of 32 packets, a present sequence number of 7149,
       every one of the last 32 sequence numbers was received, the
       authenticator length and keys is 128 bits, the encryption key is 192
       bits (actually 168 for 3DES since 1 of 8 bits is a parity bit), has
       passed 1.2 Mbytes of data in 7149 packets, was added 4593 seconds ago,
       first used 3858 seconds ago and has been idle for 23 seconds.


       /proc/net/ipsec_spi, /usr/local/bin/ipsec


       ipsec(8), ipsec_manual(8), ipsec_tncfg(5), ipsec_eroute(5),
       ipsec_spigrp(5), ipsec_klipsdebug(5), ipsec_spi(8), ipsec_version(5),


       Written for the Linux FreeS/WAN project <> by
       Richard Guy Briggs.


       The add and use times are awkward, displayed in seconds since machine
       start. It would be better to display them in seconds before now for
       human readability.

[FIXME: source]                   02/25/2010