setkey takes a series of operations from standard input (if invoked with -c) or the file named filename -f filename (if invoked with.)
PF_KEY
socket.
-xx
prints the unformatted timestamps.
PF_KEY
socket, including messages sent from other processes to the kernel.
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.
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.
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:
esp
esp-old
ah
ah-old
ipcomp
tcp
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.
transport
, tunnel
,
or
any
.
The default value is
any
.
zero-pad
random-pad
seq-pad
nocyclic-seq
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.
address
address/prefixlen
address[port]
address/prefixlen[port]
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.
/etc/protocols
as
upperspec,
or
icmp6
,
ip4
,
or
any
.
any
stands for
``any protocol''.
You can also use the protocol number.
You can specify a type and/or a code of ICMPv6 when the
upper-layer protocol is ICMPv6.
The specification can be placed after
icmp6
.
A type is separated from a code by single comma.
A code must always be specified.
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
;
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, and ICMP may not be suitable
to use with IPsec.
You have to consider carefully what to use.
- -P direction [priority specification]
discard
-
- -P direction [priority specification]
none
-
- Xo -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 policies.
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:
low
(-1073741824)
,
def
(0)
,
or
high
(1073741824)
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 10.0.11.0/24[any] 10.0.11.33/32[any] any -P out ipsec
esp/tunnel/192.168.0.1[4500]-192.168.1.2[30000]/require ;
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.
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: 96bit ICV
(draft-ietf-ipsec-ciph-sha-256-00)
256 ah-old: 128bit ICV (no document)
hmac-sha384 384 ah: 96bit ICV (no document)
384 ah-old: 128bit ICV (no document)
hmac-sha512 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)
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 draft-ietf-ipsec-ciph-aes-ctr-03
camellia-cbc 128/192/256 rfc4312
Note that the first 128 bits of a key for
aes-ctr
will be used as AES key, and the remaining 32 bits will be used as nonce.
These compression algorithms can be used as calgo in -C calgo of the protocol parameter:
algorithm
deflate rfc2394
In kernel mode, setkey manages and shows policies and SAs exactly as they are stored in the kernel.
In RFC mode, setkey
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 ;
add 10.1.10.34 10.1.10.36 tcp 0x1000 -A tcp-md5 "TCP-MD5 BGP secret" ;
add 10.0.11.41 10.0.11.33 esp 0x10001
-ctx 1 1 "system_u:system_r:unconfined_t:SystemLow-SystemHigh"
-E des-cbc 0x3ffe05014819ffff;
spdadd 10.0.11.41 10.0.11.33 any
-ctx 1 1 "system_u:system_r:unconfined_t:SystemLow-SystemHigh"
-P out ipsec esp/transport//require ;
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).