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-rw-r--r--sshd_config.597
1 files changed, 67 insertions, 30 deletions
diff --git a/sshd_config.5 b/sshd_config.5
index cfa480697..3abac6c10 100644
--- a/sshd_config.5
+++ b/sshd_config.5
@@ -33,8 +33,8 @@
33.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 33.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35.\" 35.\"
36.\" $OpenBSD: sshd_config.5,v 1.156 2013/02/06 00:20:42 dtucker Exp $ 36.\" $OpenBSD: sshd_config.5,v 1.162 2013/07/19 07:37:48 markus Exp $
37.Dd $Mdocdate: February 6 2013 $ 37.Dd $Mdocdate: July 19 2013 $
38.Dt SSHD_CONFIG 5 38.Dt SSHD_CONFIG 5
39.Os 39.Os
40.Sh NAME 40.Sh NAME
@@ -117,9 +117,7 @@ The allow/deny directives are processed in the following order:
117and finally 117and finally
118.Cm AllowGroups . 118.Cm AllowGroups .
119.Pp 119.Pp
120See 120See PATTERNS in
121.Sx PATTERNS
122in
123.Xr ssh_config 5 121.Xr ssh_config 5
124for more information on patterns. 122for more information on patterns.
125.It Cm AllowTcpForwarding 123.It Cm AllowTcpForwarding
@@ -159,9 +157,7 @@ The allow/deny directives are processed in the following order:
159and finally 157and finally
160.Cm AllowGroups . 158.Cm AllowGroups .
161.Pp 159.Pp
162See 160See PATTERNS in
163.Sx PATTERNS
164in
165.Xr ssh_config 5 161.Xr ssh_config 5
166for more information on patterns. 162for more information on patterns.
167.It Cm AuthenticationMethods 163.It Cm AuthenticationMethods
@@ -180,6 +176,20 @@ Only methods that are next in one or more lists are offered at each stage,
180so for this example, it would not be possible to attempt password or 176so for this example, it would not be possible to attempt password or
181keyboard-interactive authentication before public key. 177keyboard-interactive authentication before public key.
182.Pp 178.Pp
179For keyboard interactive authentication it is also possible to
180restrict authentication to a specific device by appending a
181colon followed by the device identifier
182.Dq bsdauth ,
183.Dq pam ,
184or
185.Dq skey ,
186depending on the server configuration.
187For example,
188.Dq keyboard-interactive:bsdauth
189would restrict keyboard interactive authentication to the
190.Dq bsdauth
191device.
192.Pp
183This option is only available for SSH protocol 2 and will yield a fatal 193This option is only available for SSH protocol 2 and will yield a fatal
184error if enabled if protocol 1 is also enabled. 194error if enabled if protocol 1 is also enabled.
185Note that each authentication method listed should also be explicitly enabled 195Note that each authentication method listed should also be explicitly enabled
@@ -188,11 +198,10 @@ The default is not to require multiple authentication; successful completion
188of a single authentication method is sufficient. 198of a single authentication method is sufficient.
189.It Cm AuthorizedKeysCommand 199.It Cm AuthorizedKeysCommand
190Specifies a program to be used to look up the user's public keys. 200Specifies a program to be used to look up the user's public keys.
191The program will be invoked with a single argument of the username 201The program must be owned by root and not writable by group or others.
202It will be invoked with a single argument of the username
192being authenticated, and should produce on standard output zero or 203being authenticated, and should produce on standard output zero or
193more lines of authorized_keys output (see 204more lines of authorized_keys output (see AUTHORIZED_KEYS in
194.Sx AUTHORIZED_KEYS
195in
196.Xr sshd 8 ) . 205.Xr sshd 8 ) .
197If a key supplied by AuthorizedKeysCommand does not successfully authenticate 206If a key supplied by AuthorizedKeysCommand does not successfully authenticate
198and authorize the user then public key authentication continues using the usual 207and authorize the user then public key authentication continues using the usual
@@ -207,7 +216,7 @@ than running authorized keys commands.
207Specifies the file that contains the public keys that can be used 216Specifies the file that contains the public keys that can be used
208for user authentication. 217for user authentication.
209The format is described in the 218The format is described in the
210.Sx AUTHORIZED_KEYS FILE FORMAT 219AUTHORIZED_KEYS FILE FORMAT
211section of 220section of
212.Xr sshd 8 . 221.Xr sshd 8 .
213.Cm AuthorizedKeysFile 222.Cm AuthorizedKeysFile
@@ -231,9 +240,7 @@ When using certificates signed by a key listed in
231this file lists names, one of which must appear in the certificate for it 240this file lists names, one of which must appear in the certificate for it
232to be accepted for authentication. 241to be accepted for authentication.
233Names are listed one per line preceded by key options (as described 242Names are listed one per line preceded by key options (as described
234in 243in AUTHORIZED_KEYS FILE FORMAT in
235.Sx AUTHORIZED_KEYS FILE FORMAT
236in
237.Xr sshd 8 ) . 244.Xr sshd 8 ) .
238Empty lines and comments starting with 245Empty lines and comments starting with
239.Ql # 246.Ql #
@@ -411,9 +418,7 @@ The allow/deny directives are processed in the following order:
411and finally 418and finally
412.Cm AllowGroups . 419.Cm AllowGroups .
413.Pp 420.Pp
414See 421See PATTERNS in
415.Sx PATTERNS
416in
417.Xr ssh_config 5 422.Xr ssh_config 5
418for more information on patterns. 423for more information on patterns.
419.It Cm DenyUsers 424.It Cm DenyUsers
@@ -432,9 +437,7 @@ The allow/deny directives are processed in the following order:
432and finally 437and finally
433.Cm AllowGroups . 438.Cm AllowGroups .
434.Pp 439.Pp
435See 440See PATTERNS in
436.Sx PATTERNS
437in
438.Xr ssh_config 5 441.Xr ssh_config 5
439for more information on patterns. 442for more information on patterns.
440.It Cm ForceCommand 443.It Cm ForceCommand
@@ -543,6 +546,18 @@ keys are used for version 1 and
543or 546or
544.Dq rsa 547.Dq rsa
545are used for version 2 of the SSH protocol. 548are used for version 2 of the SSH protocol.
549It is also possible to specify public host key files instead.
550In this case operations on the private key will be delegated
551to an
552.Xr ssh-agent 1 .
553.It Cm HostKeyAgent
554Identifies the UNIX-domain socket used to communicate
555with an agent that has access to the private host keys.
556If
557.Dq SSH_AUTH_SOCK
558is specified, the location of the socket will be read from the
559.Ev SSH_AUTH_SOCK
560environment variable.
546.It Cm IgnoreRhosts 561.It Cm IgnoreRhosts
547Specifies that 562Specifies that
548.Pa .rhosts 563.Pa .rhosts
@@ -746,8 +761,7 @@ and
746.Cm Address . 761.Cm Address .
747The match patterns may consist of single entries or comma-separated 762The match patterns may consist of single entries or comma-separated
748lists and may use the wildcard and negation operators described in the 763lists and may use the wildcard and negation operators described in the
749.Sx PATTERNS 764PATTERNS section of
750section of
751.Xr ssh_config 5 . 765.Xr ssh_config 5 .
752.Pp 766.Pp
753The patterns in an 767The patterns in an
@@ -799,6 +813,7 @@ Available keywords are
799.Cm PermitRootLogin , 813.Cm PermitRootLogin ,
800.Cm PermitTunnel , 814.Cm PermitTunnel ,
801.Cm PubkeyAuthentication , 815.Cm PubkeyAuthentication ,
816.Cm RekeyLimit ,
802.Cm RhostsRSAAuthentication , 817.Cm RhostsRSAAuthentication ,
803.Cm RSAAuthentication , 818.Cm RSAAuthentication ,
804.Cm X11DisplayOffset , 819.Cm X11DisplayOffset ,
@@ -993,6 +1008,32 @@ Specifies whether public key authentication is allowed.
993The default is 1008The default is
994.Dq yes . 1009.Dq yes .
995Note that this option applies to protocol version 2 only. 1010Note that this option applies to protocol version 2 only.
1011.It Cm RekeyLimit
1012Specifies the maximum amount of data that may be transmitted before the
1013session key is renegotiated, optionally followed a maximum amount of
1014time that may pass before the session key is renegotiated.
1015The first argument is specified in bytes and may have a suffix of
1016.Sq K ,
1017.Sq M ,
1018or
1019.Sq G
1020to indicate Kilobytes, Megabytes, or Gigabytes, respectively.
1021The default is between
1022.Sq 1G
1023and
1024.Sq 4G ,
1025depending on the cipher.
1026The optional second value is specified in seconds and may use any of the
1027units documented in the
1028.Sx TIME FORMATS
1029section.
1030The default value for
1031.Cm RekeyLimit
1032is
1033.Dq default none ,
1034which means that rekeying is performed after the cipher's default amount
1035of data has been sent or received and no time based rekeying is done.
1036This option applies to protocol version 2 only.
996.It Cm RevokedKeys 1037.It Cm RevokedKeys
997Specifies revoked public keys. 1038Specifies revoked public keys.
998Keys listed in this file will be refused for public key authentication. 1039Keys listed in this file will be refused for public key authentication.
@@ -1001,9 +1042,7 @@ be refused for all users.
1001Keys may be specified as a text file, listing one public key per line, or as 1042Keys may be specified as a text file, listing one public key per line, or as
1002an OpenSSH Key Revocation List (KRL) as generated by 1043an OpenSSH Key Revocation List (KRL) as generated by
1003.Xr ssh-keygen 1 . 1044.Xr ssh-keygen 1 .
1004For more information on KRLs, see the 1045For more information on KRLs, see the KEY REVOCATION LISTS section in
1005.Sx KEY REVOCATION LISTS
1006section in
1007.Xr ssh-keygen 1 . 1046.Xr ssh-keygen 1 .
1008.It Cm RhostsRSAAuthentication 1047.It Cm RhostsRSAAuthentication
1009Specifies whether rhosts or /etc/hosts.equiv authentication together 1048Specifies whether rhosts or /etc/hosts.equiv authentication together
@@ -1092,9 +1131,7 @@ listed in the certificate's principals list.
1092Note that certificates that lack a list of principals will not be permitted 1131Note that certificates that lack a list of principals will not be permitted
1093for authentication using 1132for authentication using
1094.Cm TrustedUserCAKeys . 1133.Cm TrustedUserCAKeys .
1095For more details on certificates, see the 1134For more details on certificates, see the CERTIFICATES section in
1096.Sx CERTIFICATES
1097section in
1098.Xr ssh-keygen 1 . 1135.Xr ssh-keygen 1 .
1099.It Cm UseDNS 1136.It Cm UseDNS
1100Specifies whether 1137Specifies whether