SYNOPSIS
     ssh-agent [-c | -s] [-k] [command [args ...]]

DESCRIPTION
     ssh-agent is a program to hold private keys used for  public
key authenti-
     cation (RSA, DSA).  The idea is that ssh-agent is started in
the begin-
     ning of an X-session or a login session, and all other  win-
dows or pro-
     grams  are  started  as  clients  to  the ssh-agent program.
Through use of
     environment variables the agent can be located and automati-
cally used for
     authentication  when  logging  in  to  other  machines using
ssh(1).

     The options are as follows:

     -c      Generate C-shell commands on stdout. This is the de-
fault if SHELL
             looks like it's a csh style of shell.

     -s       Generate  Bourne  shell commands on stdout. This is
the default if
             SHELL does not look like it's a csh style of  shell.

     -k       Kill  the current agent (given by the SSH_AGENT_PID
environment
             variable).

     If a commandline is given, this is executed as a  subprocess
of the agent.
     When the command dies, so does the agent.

     The  agent  initially  does not have any private keys.  Keys
are added using
     ssh-add(1).  When  executed  without  arguments,  ssh-add(1)
adds the
     $HOME/.ssh/identity file.  If the identity has a passphrase,
ssh-add(1)
     asks for the passphrase (using a small  X11  application  if
running under
     X11,  or  from  the terminal if running without X).  It then
sends the iden-
     tity to the agent.  Several identities can be stored in  the
agent; the
     agent  can  automatically use any of these identities.  ssh-
add -l displays
     the identities currently held by the agent.

     The idea is that the agent is run in the  user's  local  PC,

are export-
     ed,  or  you  let  the agent print the needed shell commands
(either sh(1) or
     csh(1) syntax can be generated) which can be evalled in  the
calling
     shell.  Later ssh(1) look at these variables and use them to
establish a
     connection to the agent.

     A    unix-domain    socket     is     created     (/tmp/ssh-
XXXXXXXX/agent.<pid>), and the
     name  of this socket is stored in the SSH_AUTH_SOCK environ-
ment 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.

     The SSH_AGENT_PID environment  variable  holds  the  agent's
PID.

     The  agent exits automatically when the command given on the
command line
     terminates.

FILES


     $HOME/.ssh/identity
             Contains the RSA authentication identity of the  us-
er.  This file
             should  not  be readable by anyone but the user.  It
is possible to
             specify a passphrase when generating the  key;  that
passphrase
             will  be  used  to  encrypt the private part of this
file.  This file
             is not used by ssh-agent but is  normally  added  to
the agent using
             ssh-add(1) at login time.

     $HOME/.ssh/id_dsa
             Contains  the DSA authentication identity of the us-
er.
             (/tmp/ssh-XXXXXXXX/agent.<pid>), Unix-domain sockets
used to con-
             tain  the  connection  to  the authentication agent.
These sockets
             should only be readable by the owner.   The  sockets
should get au-
             tomatically removed when the agent exits.

AUTHOR
         patented components are chosen from external  libraries.

     o   has been updated to support ssh protocol 1.5.

     o    contains  added  support for kerberos(8) authentication
and ticket
         passing.

     o   supports one-time password authentication with  skey(1).

SEE ALSO
     ssh(1),  ssh-add(1),  ssh-keygen(1),  sshd(8),  crypto(3)

BSD      Experimental                  September     25,     1999
2