'\" te
.\" To view license terms, attribution, and copyright for OpenSSH, the default path is /var/sadm/pkg/SUNWsshdr/install/copyright. If the Solaris operating environment has been installed anywhere other than the default, modify the given path to access the file at the
.\" installed location.
.\" Portions Copyright (c) 2009, Sun Microsystems, Inc. All Rights Reserved.
.TH SSH-AGENT 1 "Aug 17, 2009"
.SH NAME
ssh-agent \- authentication agent
.SH SYNOPSIS
.LP
.nf
\fBssh-agent\fR [\fB-a\fR \fIbind_address\fR] [\fB-c\fR | \fB-s\fR ] [\fB-d\fR]
     [-t \fIlife\fR] [\fIcommand\fR [\fIargs\fR]...]
.fi

.LP
.nf
\fBssh-agent\fR [\fB-c\fR | \fB-s\fR] \fB-k\fR
.fi

.SH DESCRIPTION
.LP
\fBssh-agent\fR is a program to hold private keys used for public key
authentication (\fBRSA\fR, \fBDSA\fR). \fBssh-agent\fR is often started at the
beginning of a login session. All other windows or programs are started as
clients to the \fBssh-agent\fR program. Through use of environment variables,
the agent can be located and automatically used for authentication when logging
in to other machines using \fBssh\fR(1). See the \fISystem Administration
Guide: Security Services\fR.
.sp
.LP
If a command line is given, this is executed as a subprocess of the agent. When
the command dies, so does the agent.
.sp
.LP
The agent initially does not have any private keys. Keys are added using
\fBssh-add\fR(1), which sends the identity to the agent. Several identities can
be stored in the agent; the agent can automatically use any of these
identities. Use the \fB-l\fR option in \fBssh-add\fR(1) to display the
identities currently held by the agent.
.sp
.LP
The agent is run in the user's local host. Authentication data need not be
stored on any other machine, and authentication passphrases never go over the
network. However, if the connection to the agent is forwarded over \fBSSH\fR
remote logins, the user can use the privileges given by the identities anywhere
in the network in a secure way.
.sp
.LP
There are two main ways to get an agent setup. Either you let the agent start a
new subcommand into which some environment variables are exported, or you let
the agent print the needed shell commands (either \fBsh\fR(1) or \fBcsh\fR(1)
syntax can be generated) which can be evalled in the calling shell. Later, use
\fBssh\fR(1) to look at these variables and use them to establish a connection
to the agent.
.sp
.LP
A unix-domain socket is created (\fB/tmp/ssh-XXXXXXXX/agent.\fIpid\fR\fR) and
the name of this socket is stored in the \fBSSH_AUTH_SOCK\fR environment
variable. The socket is made accessible only to the current user. This method
is easily abused by root or another instance of the same user.
.sp
.LP
The \fBSSH_AGENT_PID\fR environment variable holds the agent's \fBPID\fR.
.sp
.LP
The agent exits automatically when the command given on the command line
terminates.
.SH OPTIONS
.LP
The following options are supported:
.sp
.ne 2
.na
\fB\fB-a\fR \fIbind_address\fR\fR
.ad
.RS 19n
Binds the agent to the unix-domain socket bind_address. The default is
\fB/tmp/ssh-XXXXXXXX/agent.\fIpid\fR\fR.
.RE

.sp
.ne 2
.na
\fB\fB-c\fR\fR
.ad
.RS 19n
Generates C-shell commands on stdout. This is the default if \fBSHELL\fR
indicates that it is a csh style of shell.
.RE

.sp
.ne 2
.na
\fB\fB-d\fR\fR
.ad
.RS 19n
Debug mode. When this option is specified, \fBssh-agent\fR does not fork.
.RE

.sp
.ne 2
.na
\fB\fB-k\fR\fR
.ad
.RS 19n
Kills the current agent (given by the \fBSSH_AGENT_PID\fR environment
variable).
.RE

.sp
.ne 2
.na
\fB\fB-s\fR\fR
.ad
.RS 19n
Generates Bourne shell commands on stdout. This is the default if \fBSHELL\fR
does not indicate that it is a csh style of shell.
.RE

.sp
.ne 2
.na
\fB\fB-t\fR \fIlife\fR\fR
.ad
.RS 19n
Set a default value for the maximum lifetime (\fIlife\fR) of identities added
to the agent. \fIlife\fR can be specified in seconds or in a time format
specified in \fBsshd_config\fR(4). \fIlife\fR specified for an identity with
\fBssh-add\fR(1) overrides this value. Without this option the default maximum
\fIlife\fR is forever.
.RE

.SH EXIT STATUS
.LP
The following exit values are returned:
.sp
.ne 2
.na
\fB\fB0\fR\fR
.ad
.RS 5n
Successful completion.
.RE

.sp
.ne 2
.na
\fB\fB1\fR\fR
.ad
.RS 5n
An error occurred.
.RE

.SH FILES
.ne 2
.na
\fB\fB/tmp/ssh-XXXXXXXX/agent.\fIpid\fR\fR\fR
.ad
.sp .6
.RS 4n
Unix-domain sockets used to contain the connection to the authentication agent.
These sockets should only be readable by the owner. The sockets are removed
when the agent exits.
.RE

.SH ATTRIBUTES
.LP
See \fBattributes\fR(5) for descriptions of the following attributes:
.sp

.sp
.TS
box;
c | c
l | l .
ATTRIBUTE TYPE	ATTRIBUTE VALUE
_
Interface Stability	Committed
.TE

.SH SEE ALSO
.LP
\fBssh\fR(1), \fBssh-add\fR(1), \fBssh-keygen\fR(1), \fBsshd\fR(1M),
\fBsshd_config\fR(4), \fBattributes\fR(5)
.sp
.LP
\fISystem Administration Guide: Security Services\fR