setkey - Unix, Linux Command
NAME
setkey
- manually manipulate the IPsec SA/SP database
SYNOPSIS
setkey
[-knrv]
file ...
setkey
[-knrv]
-c
setkey
[-krv]
-f filename
setkey
[-aklPrv]
-D
setkey
[-Pvp]
-F
setkey
[-H]
-x
setkey
[-?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 standard input
(
if invoked with
-c
)
or the file named
filename
(
if invoked with
-f filename
).
Tag | Description |
(no flag)
| |
Dump the SAD entries or SPD entries contained in the specified
file.
|
-?
|
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
.Nx ,
synonym for
-H .
On other systems, synonym for
-? .
|
-k
|
Use semantics used in kernel.
Available only in Linux.
See also
-r .
|
-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.
Tag | Description |
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:
Tag | Description |
src
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
|
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
|
tcp
|
TCP-MD5 based on rfc2385
|
Tag | Description |
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.
|
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 checks dont take place.
|
-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:
|
Tag | Description |
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.
|
Tag | Description |
-f nocyclic-seq
| |
Dont 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.
|
-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.
|
Tag | Description |
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).
|
context-name
| |
The string representation of the label that is interpreted by the LSM.
|
Tag | Description |
algorithm
| |
|
-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.
Tag | Description |
src_range
dst_range
| |
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:
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.
|
upperspec
| |
Upper-layer protocol to be used.
You can use one of the words in
/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 doesnt 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.
|
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).
|
context-name
| |
The string representation of the label that is interpreted by the LSM.
|
Tag | Description |
policy
| |
policy
is in one of the following three formats:
|
-P direction [priority specification] discard
-P direction [priority specification] none
| 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 Gt]= 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:
|
Tag | Description |
{priority,prio} offset
| |
offset
is an integer in the range from -2147483647 to 214783648.
|
{priority,prio} base {+,-} offset
| |
base
is either
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 its 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 ;
|
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.
Algorithms
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: 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
|
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
|
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
Tag | Description |
|
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 ;
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 ;
|
SEE ALSO
racoon(8),
sysctl(8)
.Rs
Changed manual key configuration for IPsec
.Re
HISTORY
The
setkey
command first appeared in the 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 numbers does not work, as the gateway does not
reassemble packets
(it cannot inspect upper-layer headers).
|