NAME

     ssh-add — adds private key identities to the authentication agent

SYNOPSIS

     ssh-add [-cDdkLlXx] [-E fingerprint_hash] [-t life] [file ...]
     ssh-add -s pkcs11
     ssh-add -e pkcs11

DESCRIPTION

     ssh-add adds private key identities to the authentication agent, ssh-agent(1).  When run
     without arguments, it adds the files ~/.ssh/id_rsa, ~/.ssh/id_dsa, ~/.ssh/id_ecdsa,
     ~/.ssh/id_ed25519 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.

     The options are as follows:

     -c      Indicates that added identities should be subject to confirmation before being used
             for authentication.  Confirmation is performed by ssh-askpass(1).  Successful
             confirmation is signaled by a zero exit status from ssh-askpass(1), 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 and their
             corresponding certificates will be removed.  Otherwise, the argument list will be
             interpreted as a list of paths to public key files to specify keys and certificates
             to be removed from the agent.  If no public key is found at a given path, ssh-add
             will append .pub and retry.

     -E fingerprint_hash
             Specifies the hash algorithm used when displaying key fingerprints.  Valid options
             are: “md5” and “sha256”.  The default is “sha256”.

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

     -k      When loading keys into or deleting keys from the agent, process plain private keys
             only and skip certificates.

     -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 (by default “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_ecdsa
             Contains the protocol version 2 ECDSA authentication identity of the user.

     ~/.ssh/id_ed25519
             Contains the protocol version 2 Ed25519 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.

EXIT STATUS

     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-askpass(1), ssh-keygen(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.