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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 251d847fd..faf93fc90 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
@@ -144,9 +144,7 @@ The allow/deny directives are processed in the following order:
144and finally 144and finally
145.Cm AllowGroups . 145.Cm AllowGroups .
146.Pp 146.Pp
147See 147See PATTERNS in
148.Sx PATTERNS
149in
150.Xr ssh_config 5 148.Xr ssh_config 5
151for more information on patterns. 149for more information on patterns.
152.It Cm AllowTcpForwarding 150.It Cm AllowTcpForwarding
@@ -186,9 +184,7 @@ The allow/deny directives are processed in the following order:
186and finally 184and finally
187.Cm AllowGroups . 185.Cm AllowGroups .
188.Pp 186.Pp
189See 187See PATTERNS in
190.Sx PATTERNS
191in
192.Xr ssh_config 5 188.Xr ssh_config 5
193for more information on patterns. 189for more information on patterns.
194.It Cm AuthenticationMethods 190.It Cm AuthenticationMethods
@@ -207,6 +203,20 @@ Only methods that are next in one or more lists are offered at each stage,
207so for this example, it would not be possible to attempt password or 203so for this example, it would not be possible to attempt password or
208keyboard-interactive authentication before public key. 204keyboard-interactive authentication before public key.
209.Pp 205.Pp
206For keyboard interactive authentication it is also possible to
207restrict authentication to a specific device by appending a
208colon followed by the device identifier
209.Dq bsdauth ,
210.Dq pam ,
211or
212.Dq skey ,
213depending on the server configuration.
214For example,
215.Dq keyboard-interactive:bsdauth
216would restrict keyboard interactive authentication to the
217.Dq bsdauth
218device.
219.Pp
210This option is only available for SSH protocol 2 and will yield a fatal 220This option is only available for SSH protocol 2 and will yield a fatal
211error if enabled if protocol 1 is also enabled. 221error if enabled if protocol 1 is also enabled.
212Note that each authentication method listed should also be explicitly enabled 222Note that each authentication method listed should also be explicitly enabled
@@ -215,11 +225,10 @@ The default is not to require multiple authentication; successful completion
215of a single authentication method is sufficient. 225of a single authentication method is sufficient.
216.It Cm AuthorizedKeysCommand 226.It Cm AuthorizedKeysCommand
217Specifies a program to be used to look up the user's public keys. 227Specifies a program to be used to look up the user's public keys.
218The program will be invoked with a single argument of the username 228The program must be owned by root and not writable by group or others.
229It will be invoked with a single argument of the username
219being authenticated, and should produce on standard output zero or 230being authenticated, and should produce on standard output zero or
220more lines of authorized_keys output (see 231more lines of authorized_keys output (see AUTHORIZED_KEYS in
221.Sx AUTHORIZED_KEYS
222in
223.Xr sshd 8 ) . 232.Xr sshd 8 ) .
224If a key supplied by AuthorizedKeysCommand does not successfully authenticate 233If a key supplied by AuthorizedKeysCommand does not successfully authenticate
225and authorize the user then public key authentication continues using the usual 234and authorize the user then public key authentication continues using the usual
@@ -234,7 +243,7 @@ than running authorized keys commands.
234Specifies the file that contains the public keys that can be used 243Specifies the file that contains the public keys that can be used
235for user authentication. 244for user authentication.
236The format is described in the 245The format is described in the
237.Sx AUTHORIZED_KEYS FILE FORMAT 246AUTHORIZED_KEYS FILE FORMAT
238section of 247section of
239.Xr sshd 8 . 248.Xr sshd 8 .
240.Cm AuthorizedKeysFile 249.Cm AuthorizedKeysFile
@@ -258,9 +267,7 @@ When using certificates signed by a key listed in
258this file lists names, one of which must appear in the certificate for it 267this file lists names, one of which must appear in the certificate for it
259to be accepted for authentication. 268to be accepted for authentication.
260Names are listed one per line preceded by key options (as described 269Names are listed one per line preceded by key options (as described
261in 270in AUTHORIZED_KEYS FILE FORMAT in
262.Sx AUTHORIZED_KEYS FILE FORMAT
263in
264.Xr sshd 8 ) . 271.Xr sshd 8 ) .
265Empty lines and comments starting with 272Empty lines and comments starting with
266.Ql # 273.Ql #
@@ -442,9 +449,7 @@ The allow/deny directives are processed in the following order:
442and finally 449and finally
443.Cm AllowGroups . 450.Cm AllowGroups .
444.Pp 451.Pp
445See 452See PATTERNS in
446.Sx PATTERNS
447in
448.Xr ssh_config 5 453.Xr ssh_config 5
449for more information on patterns. 454for more information on patterns.
450.It Cm DenyUsers 455.It Cm DenyUsers
@@ -463,9 +468,7 @@ The allow/deny directives are processed in the following order:
463and finally 468and finally
464.Cm AllowGroups . 469.Cm AllowGroups .
465.Pp 470.Pp
466See 471See PATTERNS in
467.Sx PATTERNS
468in
469.Xr ssh_config 5 472.Xr ssh_config 5
470for more information on patterns. 473for more information on patterns.
471.It Cm ForceCommand 474.It Cm ForceCommand
@@ -602,6 +605,18 @@ keys are used for version 1 and
602or 605or
603.Dq rsa 606.Dq rsa
604are used for version 2 of the SSH protocol. 607are used for version 2 of the SSH protocol.
608It is also possible to specify public host key files instead.
609In this case operations on the private key will be delegated
610to an
611.Xr ssh-agent 1 .
612.It Cm HostKeyAgent
613Identifies the UNIX-domain socket used to communicate
614with an agent that has access to the private host keys.
615If
616.Dq SSH_AUTH_SOCK
617is specified, the location of the socket will be read from the
618.Ev SSH_AUTH_SOCK
619environment variable.
605.It Cm IgnoreRhosts 620.It Cm IgnoreRhosts
606Specifies that 621Specifies that
607.Pa .rhosts 622.Pa .rhosts
@@ -805,8 +820,7 @@ and
805.Cm Address . 820.Cm Address .
806The match patterns may consist of single entries or comma-separated 821The match patterns may consist of single entries or comma-separated
807lists and may use the wildcard and negation operators described in the 822lists and may use the wildcard and negation operators described in the
808.Sx PATTERNS 823PATTERNS section of
809section of
810.Xr ssh_config 5 . 824.Xr ssh_config 5 .
811.Pp 825.Pp
812The patterns in an 826The patterns in an
@@ -858,6 +872,7 @@ Available keywords are
858.Cm PermitRootLogin , 872.Cm PermitRootLogin ,
859.Cm PermitTunnel , 873.Cm PermitTunnel ,
860.Cm PubkeyAuthentication , 874.Cm PubkeyAuthentication ,
875.Cm RekeyLimit ,
861.Cm RhostsRSAAuthentication , 876.Cm RhostsRSAAuthentication ,
862.Cm RSAAuthentication , 877.Cm RSAAuthentication ,
863.Cm X11DisplayOffset , 878.Cm X11DisplayOffset ,
@@ -1066,6 +1081,32 @@ Specifies whether public key authentication is allowed.
1066The default is 1081The default is
1067.Dq yes . 1082.Dq yes .
1068Note that this option applies to protocol version 2 only. 1083Note that this option applies to protocol version 2 only.
1084.It Cm RekeyLimit
1085Specifies the maximum amount of data that may be transmitted before the
1086session key is renegotiated, optionally followed a maximum amount of
1087time that may pass before the session key is renegotiated.
1088The first argument is specified in bytes and may have a suffix of
1089.Sq K ,
1090.Sq M ,
1091or
1092.Sq G
1093to indicate Kilobytes, Megabytes, or Gigabytes, respectively.
1094The default is between
1095.Sq 1G
1096and
1097.Sq 4G ,
1098depending on the cipher.
1099The optional second value is specified in seconds and may use any of the
1100units documented in the
1101.Sx TIME FORMATS
1102section.
1103The default value for
1104.Cm RekeyLimit
1105is
1106.Dq default none ,
1107which means that rekeying is performed after the cipher's default amount
1108of data has been sent or received and no time based rekeying is done.
1109This option applies to protocol version 2 only.
1069.It Cm RevokedKeys 1110.It Cm RevokedKeys
1070Specifies revoked public keys. 1111Specifies revoked public keys.
1071Keys listed in this file will be refused for public key authentication. 1112Keys listed in this file will be refused for public key authentication.
@@ -1074,9 +1115,7 @@ be refused for all users.
1074Keys may be specified as a text file, listing one public key per line, or as 1115Keys may be specified as a text file, listing one public key per line, or as
1075an OpenSSH Key Revocation List (KRL) as generated by 1116an OpenSSH Key Revocation List (KRL) as generated by
1076.Xr ssh-keygen 1 . 1117.Xr ssh-keygen 1 .
1077For more information on KRLs, see the 1118For more information on KRLs, see the KEY REVOCATION LISTS section in
1078.Sx KEY REVOCATION LISTS
1079section in
1080.Xr ssh-keygen 1 . 1119.Xr ssh-keygen 1 .
1081.It Cm RhostsRSAAuthentication 1120.It Cm RhostsRSAAuthentication
1082Specifies whether rhosts or /etc/hosts.equiv authentication together 1121Specifies whether rhosts or /etc/hosts.equiv authentication together
@@ -1168,9 +1207,7 @@ listed in the certificate's principals list.
1168Note that certificates that lack a list of principals will not be permitted 1207Note that certificates that lack a list of principals will not be permitted
1169for authentication using 1208for authentication using
1170.Cm TrustedUserCAKeys . 1209.Cm TrustedUserCAKeys .
1171For more details on certificates, see the 1210For more details on certificates, see the CERTIFICATES section in
1172.Sx CERTIFICATES
1173section in
1174.Xr ssh-keygen 1 . 1211.Xr ssh-keygen 1 .
1175.It Cm UseDNS 1212.It Cm UseDNS
1176Specifies whether 1213Specifies whether