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-rw-r--r--ssh_config.5153
1 files changed, 116 insertions, 37 deletions
diff --git a/ssh_config.5 b/ssh_config.5
index 9033185b1..5c41189fa 100644
--- a/ssh_config.5
+++ b/ssh_config.5
@@ -34,7 +34,7 @@
34.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 34.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 35.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36.\" 36.\"
37.\" $OpenBSD: ssh_config.5,v 1.61 2005/07/08 12:53:10 jmc Exp $ 37.\" $OpenBSD: ssh_config.5,v 1.76 2006/01/20 11:21:45 jmc Exp $
38.Dd September 25, 1999 38.Dd September 25, 1999
39.Dt SSH_CONFIG 5 39.Dt SSH_CONFIG 5
40.Os 40.Os
@@ -263,8 +263,10 @@ with
263set to 263set to
264.Dq no 264.Dq no
265(the default). 265(the default).
266These sessions will reuse the master instance's network connection rather 266These sessions will try to reuse the master instance's network connection
267than initiating new ones. 267rather than initiating new ones, but will fall back to connecting normally
268if the control socket does not exist, or is not listening.
269.Pp
268Setting this to 270Setting this to
269.Dq ask 271.Dq ask
270will cause 272will cause
@@ -283,7 +285,7 @@ will continue without connecting to a master instance.
283X11 and 285X11 and
284.Xr ssh-agent 1 286.Xr ssh-agent 1
285forwarding is supported over these multiplexed connections, however the 287forwarding is supported over these multiplexed connections, however the
286display and agent fowarded will be the one belonging to the master 288display and agent forwarded will be the one belonging to the master
287connection i.e. it is not possible to forward multiple displays or agents. 289connection i.e. it is not possible to forward multiple displays or agents.
288.Pp 290.Pp
289Two additional options allow for opportunistic multiplexing: try to use a 291Two additional options allow for opportunistic multiplexing: try to use a
@@ -316,11 +318,33 @@ used for opportunistic connection sharing include
316all three of these escape sequences. 318all three of these escape sequences.
317This ensures that shared connections are uniquely identified. 319This ensures that shared connections are uniquely identified.
318.It Cm DynamicForward 320.It Cm DynamicForward
319Specifies that a TCP/IP port on the local machine be forwarded 321Specifies that a TCP port on the local machine be forwarded
320over the secure channel, and the application 322over the secure channel, and the application
321protocol is then used to determine where to connect to from the 323protocol is then used to determine where to connect to from the
322remote machine. 324remote machine.
323The argument must be a port number. 325.Pp
326The argument must be
327.Sm off
328.Oo Ar bind_address : Oc Ar port .
329.Sm on
330IPv6 addresses can be specified by enclosing addresses in square brackets or
331by using an alternative syntax:
332.Oo Ar bind_address Ns / Oc Ns Ar port .
333By default, the local port is bound in accordance with the
334.Cm GatewayPorts
335setting.
336However, an explicit
337.Ar bind_address
338may be used to bind the connection to a specific address.
339The
340.Ar bind_address
341of
342.Dq localhost
343indicates that the listening port be bound for local use only, while an
344empty address or
345.Sq *
346indicates that the port should be available from all interfaces.
347.Pp
324Currently the SOCKS4 and SOCKS5 protocols are supported, and 348Currently the SOCKS4 and SOCKS5 protocols are supported, and
325.Nm ssh 349.Nm ssh
326will act as a SOCKS server. 350will act as a SOCKS server.
@@ -503,23 +527,6 @@ Default is the name given on the command line.
503Numeric IP addresses are also permitted (both on the command line and in 527Numeric IP addresses are also permitted (both on the command line and in
504.Cm HostName 528.Cm HostName
505specifications). 529specifications).
506.It Cm IdentityFile
507Specifies a file from which the user's RSA or DSA authentication identity
508is read.
509The default is
510.Pa ~/.ssh/identity
511for protocol version 1, and
512.Pa ~/.ssh/id_rsa
513and
514.Pa ~/.ssh/id_dsa
515for protocol version 2.
516Additionally, any identities represented by the authentication agent
517will be used for authentication.
518The file name may use the tilde
519syntax to refer to a user's home directory.
520It is possible to have
521multiple identity files specified in configuration files; all these
522identities will be tried in sequence.
523.It Cm IdentitiesOnly 530.It Cm IdentitiesOnly
524Specifies that 531Specifies that
525.Nm ssh 532.Nm ssh
@@ -533,17 +540,42 @@ The argument to this keyword must be
533.Dq yes 540.Dq yes
534or 541or
535.Dq no . 542.Dq no .
536This option is intented for situations where 543This option is intended for situations where
537.Nm ssh-agent 544.Nm ssh-agent
538offers many different identities. 545offers many different identities.
539The default is 546The default is
540.Dq no . 547.Dq no .
548.It Cm IdentityFile
549Specifies a file from which the user's RSA or DSA authentication identity
550is read.
551The default is
552.Pa ~/.ssh/identity
553for protocol version 1, and
554.Pa ~/.ssh/id_rsa
555and
556.Pa ~/.ssh/id_dsa
557for protocol version 2.
558Additionally, any identities represented by the authentication agent
559will be used for authentication.
560The file name may use the tilde
561syntax to refer to a user's home directory.
562It is possible to have
563multiple identity files specified in configuration files; all these
564identities will be tried in sequence.
541.It Cm KbdInteractiveDevices 565.It Cm KbdInteractiveDevices
542Specifies the list of methods to use in keyboard-interactive authentication. 566Specifies the list of methods to use in keyboard-interactive authentication.
543Multiple method names must be comma-separated. 567Multiple method names must be comma-separated.
544The default is to use the server specified list. 568The default is to use the server specified list.
569.It Cm LocalCommand
570Specifies a command to execute on the local machine after successfully
571connecting to the server.
572The command string extends to the end of the line, and is executed with
573.Pa /bin/sh .
574This directive is ignored unless
575.Cm PermitLocalCommand
576has been enabled.
545.It Cm LocalForward 577.It Cm LocalForward
546Specifies that a TCP/IP port on the local machine be forwarded over 578Specifies that a TCP port on the local machine be forwarded over
547the secure channel to the specified host and port from the remote machine. 579the secure channel to the specified host and port from the remote machine.
548The first argument must be 580The first argument must be
549.Sm off 581.Sm off
@@ -611,6 +643,19 @@ or
611.Dq no . 643.Dq no .
612The default is 644The default is
613.Dq yes . 645.Dq yes .
646.It Cm PermitLocalCommand
647Allow local command execution via the
648.Ic LocalCommand
649option or using the
650.Ic !\& Ns Ar command
651escape sequence in
652.Xr ssh 1 .
653The argument must be
654.Dq yes
655or
656.Dq no .
657The default is
658.Dq no .
614.It Cm Port 659.It Cm Port
615Specifies the port number to connect on the remote host. 660Specifies the port number to connect on the remote host.
616Default is 22. 661Default is 22.
@@ -683,8 +728,23 @@ or
683The default is 728The default is
684.Dq yes . 729.Dq yes .
685This option applies to protocol version 2 only. 730This option applies to protocol version 2 only.
731.It Cm RekeyLimit
732Specifies the maximum amount of data that may be transmitted before the
733session key is renegotiated.
734The argument is the number of bytes, with an optional suffix of
735.Sq K ,
736.Sq M ,
737or
738.Sq G
739to indicate Kilobytes, Megabytes, or Gigabytes, respectively.
740The default is between
741.Dq 1G
742and
743.Dq 4G ,
744depending on the cipher.
745This option applies to protocol version 2 only.
686.It Cm RemoteForward 746.It Cm RemoteForward
687Specifies that a TCP/IP port on the remote machine be forwarded over 747Specifies that a TCP port on the remote machine be forwarded over
688the secure channel to the specified host and port from the local machine. 748the secure channel to the specified host and port from the local machine.
689The first argument must be 749The first argument must be
690.Sm off 750.Sm off
@@ -761,17 +821,8 @@ across multiple
761.Cm SendEnv 821.Cm SendEnv
762directives. 822directives.
763The default is not to send any environment variables. 823The default is not to send any environment variables.
764.It Cm ServerAliveInterval
765Sets a timeout interval in seconds after which if no data has been received
766from the server,
767.Nm ssh
768will send a message through the encrypted
769channel to request a response from the server.
770The default
771is 0, indicating that these messages will not be sent to the server.
772This option applies to protocol version 2 only.
773.It Cm ServerAliveCountMax 824.It Cm ServerAliveCountMax
774Sets the number of server alive messages (see above) which may be 825Sets the number of server alive messages (see below) which may be
775sent without 826sent without
776.Nm ssh 827.Nm ssh
777receiving any messages back from the server. 828receiving any messages back from the server.
@@ -793,10 +844,19 @@ server depend on knowing when a connection has become inactive.
793The default value is 3. 844The default value is 3.
794If, for example, 845If, for example,
795.Cm ServerAliveInterval 846.Cm ServerAliveInterval
796(above) is set to 15, and 847(see below) is set to 15, and
797.Cm ServerAliveCountMax 848.Cm ServerAliveCountMax
798is left at the default, if the server becomes unresponsive ssh 849is left at the default, if the server becomes unresponsive ssh
799will disconnect after approximately 45 seconds. 850will disconnect after approximately 45 seconds.
851.It Cm ServerAliveInterval
852Sets a timeout interval in seconds after which if no data has been received
853from the server,
854.Nm ssh
855will send a message through the encrypted
856channel to request a response from the server.
857The default
858is 0, indicating that these messages will not be sent to the server.
859This option applies to protocol version 2 only.
800.It Cm SmartcardDevice 860.It Cm SmartcardDevice
801Specifies which smartcard device to use. 861Specifies which smartcard device to use.
802The argument to this keyword is the device 862The argument to this keyword is the device
@@ -856,6 +916,25 @@ This is important in scripts, and many users want it too.
856.Pp 916.Pp
857To disable TCP keepalive messages, the value should be set to 917To disable TCP keepalive messages, the value should be set to
858.Dq no . 918.Dq no .
919.It Cm Tunnel
920Request starting
921.Xr tun 4
922device forwarding between the client and the server.
923This option also allows requesting layer 2 (ethernet)
924instead of layer 3 (point-to-point) tunneling from the server.
925The argument must be
926.Dq yes ,
927.Dq point-to-point ,
928.Dq ethernet
929or
930.Dq no .
931The default is
932.Dq no .
933.It Cm TunnelDevice
934Force a specified
935.Xr tun 4
936device on the client.
937Without this option, the next available device will be used.
859.It Cm UsePrivilegedPort 938.It Cm UsePrivilegedPort
860Specifies whether to use a privileged port for outgoing connections. 939Specifies whether to use a privileged port for outgoing connections.
861The argument must be 940The argument must be