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NAME

     ssh-add - adds RSA or DSA identities to the authentication agent

SYNOPSIS

     ssh-add [-cDdLlXx] [-t life] [file ...]
     ssh-add -s pkcs11
     ssh-add -e pkcs11

DESCRIPTION

     ssh-add adds RSA or DSA identities to the authentication agent,
     ssh-agent(1).  When run without arguments, it adds the files
     ~/.ssh/id_rsa, ~/.ssh/id_dsa and ~/.ssh/identity.  After loading a
     private key, ssh-add will try to load corresponding certificate
     information from the filename obtained by appending -cert.pub to the name
     of the private key file.  Alternative file names can be given on the
     command line.

     If any file requires a passphrase, ssh-add asks for the passphrase from
     the user.  The passphrase is read from the user’s tty.  ssh-add retries
     the last passphrase if multiple identity files are given.

     The authentication agent must be running and the SSH_AUTH_SOCK
     environment variable must contain the name of its socket for ssh-add to
     work.

     Any keys recorded in the blacklist of known-compromised keys (see
     ssh-vulnkey(1)) will be refused.

     The options are as follows:

     -c      Indicates that added identities should be subject to confirmation
             before being used for authentication.  Confirmation is performed
             by the SSH_ASKPASS program mentioned below.  Successful
             confirmation is signaled by a zero exit status from the
             SSH_ASKPASS program, rather than text entered into the requester.

     -D      Deletes all identities from the agent.

     -d      Instead of adding identities, removes identities from the agent.
             If ssh-add has been run without arguments, the keys for the
             default identities will be removed.  Otherwise, the argument list
             will be interpreted as a list of paths to public key files and
             matching keys will be removed from the agent.  If no public key
             is found at a given path, ssh-add will append .pub and retry.

     -e pkcs11
             Remove keys provided by the PKCS#11 shared library pkcs11.

     -L      Lists public key parameters of all identities currently
             represented by the agent.

     -l      Lists fingerprints of all identities currently represented by the
             agent.

     -s pkcs11
             Add keys provided by the PKCS#11 shared library pkcs11.

     -t life
             Set a maximum lifetime when adding identities to an agent.  The
             lifetime may be specified in seconds or in a time format
             specified in sshd_config(5).

     -X      Unlock the agent.

     -x      Lock the agent with a password.

ENVIRONMENT

     DISPLAY and SSH_ASKPASS
             If ssh-add needs a passphrase, it will read the passphrase from
             the current terminal if it was run from a terminal.  If ssh-add
             does not have a terminal associated with it but DISPLAY and
             SSH_ASKPASS are set, it will execute the program specified by
             SSH_ASKPASS and open an X11 window to read the passphrase.  This
             is particularly useful when calling ssh-add from a .xsession or
             related script.  (Note that on some machines it may be necessary
             to redirect the input from /dev/null to make this work.)

     SSH_AUTH_SOCK
             Identifies the path of a UNIX-domain socket used to communicate
             with the agent.

FILES

     ~/.ssh/identity
             Contains the protocol version 1 RSA authentication identity of
             the user.

     ~/.ssh/id_dsa
             Contains the protocol version 2 DSA authentication identity of
             the user.

     ~/.ssh/id_rsa
             Contains the protocol version 2 RSA authentication identity of
             the user.

     Identity files should not be readable by anyone but the user.  Note that
     ssh-add ignores identity files if they are accessible by others.

DIAGNOSTICS

     Exit status is 0 on success, 1 if the specified command fails, and 2 if
     ssh-add is unable to contact the authentication agent.

SEE ALSO

     ssh(1), ssh-agent(1), ssh-keygen(1), ssh-vulnkey(1), sshd(8)

AUTHORS

     OpenSSH is a derivative of the original and free ssh 1.2.12 release by
     Tatu Ylonen.  Aaron Campbell, Bob Beck, Markus Friedl, Niels Provos, Theo
     de Raadt and Dug Song removed many bugs, re-added newer features and
     created OpenSSH.  Markus Friedl contributed the support for SSH protocol
     versions 1.5 and 2.0.