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SETKEY(8) BSD System Manager's Manual SETKEY(8)
NAME
setkey - manually manipulate the IPsec SA/SP database
SYNOPSIS
setkey [-vrk] file ...
setkey [-vrk] -c
setkey [-vrk] -f filename
setkey [-aPlvrk] -D
setkey [-Pv] -F
setkey [-H] -x
setkey [-h] [-V]
DESCRIPTION
setkey adds, updates, dumps, or flushes Security Association Database
(SAD) entries as well as Security Policy Database (SPD) entries in the
kernel.
setkey takes a series of operations from the 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
file.
-D Dump the SAD entries. If with -P, the SPD entries are dumped.
-F Flush the SAD entries. If with -P, the SPD entries are flushed.
-a setkey usually does not display dead SAD entries with -D. If
with -a, the dead SAD entries will be displayed as well. A dead
SAD entry means that it has been expired but remains in the sys-
tem because it is referenced by some SPD entries.
-H Add hexadecimal dump on -x mode.
-l Loop forever with short output on -D.
-v Be verbose. The program will dump messages exchanged on PF_KEY
socket, including messages sent from other processes to the ker-
nel.
-r Use semantics described in IPSec RFCs. This mode is default. For
details see section RFC(vs) Linux kernel semantics. Available
only in Linux.
-k Use semantics used in kernel. Available only in Linux.
-x Loop forever and dump all the messages transmitted to PF_KEY
socket. -xx makes each timestamps unformatted.
-h Print short help.
-V Print version string.
Configuration syntax
With -c or -f on the command line, setkey accepts the following configu-
ration syntax. Lines starting with hash signs ('#') are treated as com-
ment lines.
add [-46n] src dst protocol spi [extensions] algorithm ... ;
Add an SAD entry. add can fail with multiple reasons, including
when the key length does not match the specified algorithm.
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 policy ;
Add an SPD entry.
spdadd tagged tag policy ;
Add an SPD entry based on PF tag. tag must be a string sur-
rounded by doublequote.
spddelete [-46n] src_range dst_range upperspec -P direction ;
Delete an SPD entry.
spdflush ;
Clear all SPD entries. -FP on the command line achieves the
same functionality.
spddump ;
Dumps all SPD entries. -DP on the command line achieves the
same functionality.
Meta-arguments are as follows:
src
dst Source/destination of the secure communication is specified as
IPv4/v6 address. 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 restricts the address
resolution of FQDN in certain ways. -4 and -6 restrict results
into IPv4/v6 addresses only, respectively. -n avoids FQDN reso-
lution and requires addresses to be numeric addresses.
protocol
protocol is one of following:
esp ESP based on rfc2406
esp-old ESP based on rfc1827
ah AH based on rfc2402
ah-old AH based on rfc1826
ipcomp IPComp
spi Security Parameter Index (SPI) for the SAD and the SPD. spi
must be a decimal number, or a hexadecimal number with "0x" pre-
fix. SPI values between 0 and 255 are reserved for future use
by IANA and they cannot be used.
extensions
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 check don't take
place.
-u id Specify the identifier of the policy entry in SPD.
See policy.
-f pad_option
defines the content of the ESP padding. pad_option
is one of following:
zero-pad All of the padding are zero.
random-pad A series of randomized values are set.
seq-pad A series of sequential increasing num-
bers started from 1 are set.
-f nocyclic-seq
Don't allow cyclic sequence number.
-lh time
-ls time Specify hard/soft life time duration of the SA mea-
sured in seconds.
-bh bytes
-bs bytes Specify hard/soft life time duration of the SA mea-
sured in bytes transported.
algorithm
-E ealgo key
Specify a encryption algorithm ealgo for ESP.
-E ealgo key -A aalgo key
Specify a 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, 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 double-quoted character string, or a series of hex-
adecimal digits preceded by "0x".
Possible values for ealgo, aalgo and calgo are specified in sep-
arate section.
src_range
dst_range
These are selections of the secure communication specified as
IPv4/v6 address or IPv4/v6 address range, and it may accompany
TCP/UDP port specification. This takes the following form:
address
address/prefixlen
address[port]
address/prefixlen[port]
prefixlen and port must be decimal number. The square bracket
around port is really necessary. They are not manpage metachar-
acters. For FQDN resolution, the rules applicable to src and
dst apply here as well.
upperspec
Upper-layer protocol to be used. You can use one of words in
/etc/protocols as upperspec. Or icmp6, ip4, and any can be
specified. any stands for "any protocol". Also you can use the
protocol number. You can specify a type and/or a code of ICMPv6
when Upper-layer protocol is ICMPv6. the specification can be
placed after icmp6. A type is separated with a code by single
comma. A code must be specified anytime. When a zero is speci-
fied, the kernel deals with it as a wildcard. Note that the
kernel can not distinguish a wildcard from that a type of ICMPv6
is zero. For example, the following means the policy doesn't
require IPsec for any inbound Neighbor Solicitation.
spdadd ::/0 ::/0 icmp6 135,0 -P in none;
NOTE: upperspec does not work against forwarding case at this
moment, as it requires extra reassembly at forwarding node (not
implemented at this moment). We have many protocols in
/etc/protocols, but protocols except of TCP, UDP and ICMP may
not be suitable to use with IPsec. You have to consider and be
careful to use them.
policy policy is the one of the following three formats:
-P direction discard
-P direction none
-P direction ipsec
protocol/mode/src-dst/level [...]
You must specify the direction of its policy as direction.
Either out , in or fwd are used. discard means the packet
matching indexes will be discarded. none means that IPsec oper-
ation will not take place onto the packet. ipsec means that
IPsec operation will take place onto the packet. The part of
protocol/mode/src-dst/level specifies the rule how to process
the packet. Either ah, esp or ipcomp is to be set as protocol.
mode is either transport or tunnel. If mode is tunnel, you must
specify the end-points 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 request getting SA to the key exchange daemon. default
means the kernel consults to the system wide default against
protocol you specified, e.g. esp_trans_deflev sysctl variable,
when the kernel processes the packet. use means that the kernel
use a 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 to
require, in addition, it allows the policy to bind with the
unique out-bound SA. You just specify the policy level unique,
racoon(8) will configure the SA for the policy. If you config-
ure the SA by manual keying for that policy, you can put the
decimal number as the policy identifier after unique separated
by colon ':' like the following; 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 AH header followed
by 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.
Note that "discard" and "none" are not in the syntax described
in ipsec_set_policy(3). There are little differences in the
syntax. See ipsec_set_policy(3) for detail.
Algorithms
The following list shows the supported algorithms. protocol and
algorithm are almost orthogonal. Followings are the list of authentica-
tion algorithms that can be used as aalgo in -A aalgo of protocol param-
eter:
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-sha2-256 256 ah: 96bit ICV
(draft-ietf-ipsec-ciph-sha-256-00)
256 ah-old: 128bit ICV (no document)
hmac-sha2-384 384 ah: 96bit ICV (no document)
384 ah-old: 128bit ICV (no document)
hmac-sha2-512 512 ah: 96bit ICV (no document)
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)
Followings are the list of encryption algorithms that can be used as
ealgo in -E ealgo of 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 draft-ietf-ipsec-ciph-aes-ctr-03
Note that the first 128 bits of a key for aes-ctr will be used as AES
key, and remaining 32 bits will be used as nonce.
Followings are the list of compression algorithms that can be used as
calgo in -C calgo of protocol parameter:
algorithm
deflate rfc2394
RFC vs Linux kernel semantics
Linux kernel uses fwd policy instead of 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
RETURN VALUES
The command exits with 0 on success, and non-zero on errors.
EXAMPLES
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 10.0.11.41 10.0.11.33 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 10.0.11.41/32[21] 10.0.11.33/32[any] any
-P out ipsec esp/tunnel/192.168.0.1-192.168.1.2/require ;
SEE ALSO
ipsec_set_policy(3), racoon(8), sysctl(8)
Changed manual key configuration for IPsec, October 1999,
http://www.kame.net/newsletter/19991007/.
HISTORY
The setkey command first appeared in WIDE Hydrangea IPv6 protocol stack
kit. The command was completely re-designed in June 1998.
BUGS
setkey should report and handle syntax errors better.
For IPsec gateway configuration, src_range and dst_range with TCP/UDP
port number do not work, as the gateway does not reassemble packets
(cannot inspect upper-layer headers).
KAME March 19, 2004 KAME
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