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-rw-r--r--ssh_config.5162
1 files changed, 121 insertions, 41 deletions
diff --git a/ssh_config.5 b/ssh_config.5
index b232a0203..889def626 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
@@ -270,8 +270,10 @@ with
270set to 270set to
271.Dq no 271.Dq no
272(the default). 272(the default).
273These sessions will reuse the master instance's network connection rather 273These sessions will try to reuse the master instance's network connection
274than initiating new ones. 274rather than initiating new ones, but will fall back to connecting normally
275if the control socket does not exist, or is not listening.
276.Pp
275Setting this to 277Setting this to
276.Dq ask 278.Dq ask
277will cause 279will cause
@@ -290,7 +292,7 @@ will continue without connecting to a master instance.
290X11 and 292X11 and
291.Xr ssh-agent 1 293.Xr ssh-agent 1
292forwarding is supported over these multiplexed connections, however the 294forwarding is supported over these multiplexed connections, however the
293display and agent fowarded will be the one belonging to the master 295display and agent forwarded will be the one belonging to the master
294connection i.e. it is not possible to forward multiple displays or agents. 296connection i.e. it is not possible to forward multiple displays or agents.
295.Pp 297.Pp
296Two additional options allow for opportunistic multiplexing: try to use a 298Two additional options allow for opportunistic multiplexing: try to use a
@@ -323,11 +325,33 @@ used for opportunistic connection sharing include
323all three of these escape sequences. 325all three of these escape sequences.
324This ensures that shared connections are uniquely identified. 326This ensures that shared connections are uniquely identified.
325.It Cm DynamicForward 327.It Cm DynamicForward
326Specifies that a TCP/IP port on the local machine be forwarded 328Specifies that a TCP port on the local machine be forwarded
327over the secure channel, and the application 329over the secure channel, and the application
328protocol is then used to determine where to connect to from the 330protocol is then used to determine where to connect to from the
329remote machine. 331remote machine.
330The argument must be a port number. 332.Pp
333The argument must be
334.Sm off
335.Oo Ar bind_address : Oc Ar port .
336.Sm on
337IPv6 addresses can be specified by enclosing addresses in square brackets or
338by using an alternative syntax:
339.Oo Ar bind_address Ns / Oc Ns Ar port .
340By default, the local port is bound in accordance with the
341.Cm GatewayPorts
342setting.
343However, an explicit
344.Ar bind_address
345may be used to bind the connection to a specific address.
346The
347.Ar bind_address
348of
349.Dq localhost
350indicates that the listening port be bound for local use only, while an
351empty address or
352.Sq *
353indicates that the port should be available from all interfaces.
354.Pp
331Currently the SOCKS4 and SOCKS5 protocols are supported, and 355Currently the SOCKS4 and SOCKS5 protocols are supported, and
332.Nm ssh 356.Nm ssh
333will act as a SOCKS server. 357will act as a SOCKS server.
@@ -501,23 +525,6 @@ Default is the name given on the command line.
501Numeric IP addresses are also permitted (both on the command line and in 525Numeric IP addresses are also permitted (both on the command line and in
502.Cm HostName 526.Cm HostName
503specifications). 527specifications).
504.It Cm IdentityFile
505Specifies a file from which the user's RSA or DSA authentication identity
506is read.
507The default is
508.Pa ~/.ssh/identity
509for protocol version 1, and
510.Pa ~/.ssh/id_rsa
511and
512.Pa ~/.ssh/id_dsa
513for protocol version 2.
514Additionally, any identities represented by the authentication agent
515will be used for authentication.
516The file name may use the tilde
517syntax to refer to a user's home directory.
518It is possible to have
519multiple identity files specified in configuration files; all these
520identities will be tried in sequence.
521.It Cm IdentitiesOnly 528.It Cm IdentitiesOnly
522Specifies that 529Specifies that
523.Nm ssh 530.Nm ssh
@@ -531,17 +538,42 @@ The argument to this keyword must be
531.Dq yes 538.Dq yes
532or 539or
533.Dq no . 540.Dq no .
534This option is intented for situations where 541This option is intended for situations where
535.Nm ssh-agent 542.Nm ssh-agent
536offers many different identities. 543offers many different identities.
537The default is 544The default is
538.Dq no . 545.Dq no .
546.It Cm IdentityFile
547Specifies a file from which the user's RSA or DSA authentication identity
548is read.
549The default is
550.Pa ~/.ssh/identity
551for protocol version 1, and
552.Pa ~/.ssh/id_rsa
553and
554.Pa ~/.ssh/id_dsa
555for protocol version 2.
556Additionally, any identities represented by the authentication agent
557will be used for authentication.
558The file name may use the tilde
559syntax to refer to a user's home directory.
560It is possible to have
561multiple identity files specified in configuration files; all these
562identities will be tried in sequence.
539.It Cm KbdInteractiveDevices 563.It Cm KbdInteractiveDevices
540Specifies the list of methods to use in keyboard-interactive authentication. 564Specifies the list of methods to use in keyboard-interactive authentication.
541Multiple method names must be comma-separated. 565Multiple method names must be comma-separated.
542The default is to use the server specified list. 566The default is to use the server specified list.
567.It Cm LocalCommand
568Specifies a command to execute on the local machine after successfully
569connecting to the server.
570The command string extends to the end of the line, and is executed with
571.Pa /bin/sh .
572This directive is ignored unless
573.Cm PermitLocalCommand
574has been enabled.
543.It Cm LocalForward 575.It Cm LocalForward
544Specifies that a TCP/IP port on the local machine be forwarded over 576Specifies that a TCP port on the local machine be forwarded over
545the secure channel to the specified host and port from the remote machine. 577the secure channel to the specified host and port from the remote machine.
546The first argument must be 578The first argument must be
547.Sm off 579.Sm off
@@ -609,6 +641,19 @@ or
609.Dq no . 641.Dq no .
610The default is 642The default is
611.Dq yes . 643.Dq yes .
644.It Cm PermitLocalCommand
645Allow local command execution via the
646.Ic LocalCommand
647option or using the
648.Ic !\& Ns Ar command
649escape sequence in
650.Xr ssh 1 .
651The argument must be
652.Dq yes
653or
654.Dq no .
655The default is
656.Dq no .
612.It Cm Port 657.It Cm Port
613Specifies the port number to connect on the remote host. 658Specifies the port number to connect on the remote host.
614Default is 22. 659Default is 22.
@@ -681,8 +726,23 @@ or
681The default is 726The default is
682.Dq yes . 727.Dq yes .
683This option applies to protocol version 2 only. 728This option applies to protocol version 2 only.
729.It Cm RekeyLimit
730Specifies the maximum amount of data that may be transmitted before the
731session key is renegotiated.
732The argument is the number of bytes, with an optional suffix of
733.Sq K ,
734.Sq M ,
735or
736.Sq G
737to indicate Kilobytes, Megabytes, or Gigabytes, respectively.
738The default is between
739.Dq 1G
740and
741.Dq 4G ,
742depending on the cipher.
743This option applies to protocol version 2 only.
684.It Cm RemoteForward 744.It Cm RemoteForward
685Specifies that a TCP/IP port on the remote machine be forwarded over 745Specifies that a TCP port on the remote machine be forwarded over
686the secure channel to the specified host and port from the local machine. 746the secure channel to the specified host and port from the local machine.
687The first argument must be 747The first argument must be
688.Sm off 748.Sm off
@@ -759,21 +819,8 @@ across multiple
759.Cm SendEnv 819.Cm SendEnv
760directives. 820directives.
761The default is not to send any environment variables. 821The default is not to send any environment variables.
762.It Cm ServerAliveInterval
763Sets a timeout interval in seconds after which if no data has been received
764from the server,
765.Nm ssh
766will send a message through the encrypted
767channel to request a response from the server.
768The default
769is 0, indicating that these messages will not be sent to the server,
770or 300 if the
771.Cm BatchMode
772option is set.
773.Cm ProtocolKeepAlives
774is a Debian-specific compatibility alias for this option.
775.It Cm ServerAliveCountMax 822.It Cm ServerAliveCountMax
776Sets the number of server alive messages (see above) which may be 823Sets the number of server alive messages (see below) which may be
777sent without 824sent without
778.Nm ssh 825.Nm ssh
779receiving any messages back from the server. 826receiving any messages back from the server.
@@ -795,7 +842,7 @@ server depend on knowing when a connection has become inactive.
795The default value is 3. 842The default value is 3.
796If, for example, 843If, for example,
797.Cm ServerAliveInterval 844.Cm ServerAliveInterval
798(above) is set to 15, and 845(see below) is set to 15, and
799.Cm ServerAliveCountMax 846.Cm ServerAliveCountMax
800is left at the default, if the server becomes unresponsive ssh 847is left at the default, if the server becomes unresponsive ssh
801will disconnect after approximately 45 seconds. 848will disconnect after approximately 45 seconds.
@@ -803,6 +850,20 @@ This option works when using protocol version 2 only; in protocol version
8031 there is no mechanism to request a response from the server to the 8501 there is no mechanism to request a response from the server to the
804server alive messages, so disconnection is the responsibility of the TCP 851server alive messages, so disconnection is the responsibility of the TCP
805stack. 852stack.
853.It Cm ServerAliveInterval
854Sets a timeout interval in seconds after which if no data has been received
855from the server,
856.Nm ssh
857will send a message through the encrypted
858channel to request a response from the server.
859The default
860is 0, indicating that these messages will not be sent to the server,
861or 300 if the
862.Cm BatchMode
863option is set.
864This option applies to protocol version 2 only.
865.Cm ProtocolKeepAlives
866is a Debian-specific compatibility alias for this option.
806.It Cm SetupTimeOut 867.It Cm SetupTimeOut
807Normally, 868Normally,
808.Nm ssh 869.Nm ssh
@@ -885,6 +946,25 @@ This is important in scripts, and many users want it too.
885.Pp 946.Pp
886To disable TCP keepalive messages, the value should be set to 947To disable TCP keepalive messages, the value should be set to
887.Dq no . 948.Dq no .
949.It Cm Tunnel
950Request starting
951.Xr tun 4
952device forwarding between the client and the server.
953This option also allows requesting layer 2 (ethernet)
954instead of layer 3 (point-to-point) tunneling from the server.
955The argument must be
956.Dq yes ,
957.Dq point-to-point ,
958.Dq ethernet
959or
960.Dq no .
961The default is
962.Dq no .
963.It Cm TunnelDevice
964Force a specified
965.Xr tun 4
966device on the client.
967Without this option, the next available device will be used.
888.It Cm UsePrivilegedPort 968.It Cm UsePrivilegedPort
889Specifies whether to use a privileged port for outgoing connections. 969Specifies whether to use a privileged port for outgoing connections.
890The argument must be 970The argument must be