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Updated: Wednesday, July 27, 2022
 
 

ssh-add (1)

Name

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

Synopsis

ssh-add [-cDdKkLlqvXx] [-E fingerprint_hash] [-S provider] [-t life]
[file ...]
ssh-add -s pkcs11
ssh-add -e pkcs11
ssh-add -T pubkey ...

Description

SSH-ADD(1)                BSD General Commands Manual               SSH-ADD(1)

NAME
     ssh-add -- adds private key identities to the OpenSSH authentication
     agent

SYNOPSIS
     ssh-add [-cDdKkLlqvXx] [-E fingerprint_hash] [-S provider] [-t life]
             [file ...]
     ssh-add -s pkcs11
     ssh-add -e pkcs11
     ssh-add -T pubkey ...

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_ecdsa_sk,
     ~/.ssh/id_ed25519, and ~/.ssh/id_ed25519_sk.  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 environ-
     ment 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 certifi-
             cates to be removed from the agent.  If no public key is found at
             a given path, ssh-add will append .pub and retry.  If the argu-
             ment list consists of ``-'' then ssh-add will read public keys to
             be removed from standard input.

     -E fingerprint_hash
             Specifies the hash algorithm used when displaying key finger-
             prints.  Valid options are: ``md5'' and ``sha256''.  The default
             is ``sha256''.  If OpenSSL is running in FIPS-140 mode, the only
             supported option is ``sha256''.

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

     -K      Load resident keys from a FIDO authenticator.

     -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 repre-
             sented by the agent.

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

     -q      Be quiet after a successful operation.

     -S provider
             Specifies a path to a library that will be used when adding FIDO
             authenticator-hosted keys, overriding the default of using the
             internal USB HID support.

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

     -T pubkey ...
             Tests whether the private keys that correspond to the specified
             pubkey files are usable by performing sign and verify operations
             on each.

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

     -v      Verbose mode.  Causes ssh-add to print debugging messages about
             its progress.  This is helpful in debugging problems.  Multiple
             -v options increase the verbosity.  The maximum is 3.

     -X      Unlock the agent.

     -x      Lock the agent with a password.

ENVIRONMENT
     DISPLAY, SSH_ASKPASS and SSH_ASKPASS_REQUIRE
             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.

             SSH_ASKPASS_REQUIRE allows further control over the use of an
             askpass program.  If this variable is set to ``never'' then
             ssh-add will never attempt to use one.  If it is set to
             ``prefer'', then ssh-add will prefer to use the askpass program
             instead of the TTY when requesting passwords.  Finally, if the
             variable is set to ``force'', then the askpass program will be
             used for all passphrase input regardless of whether DISPLAY is
             set.

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

     SSH_SK_PROVIDER
             Specifies a path to a library that will be used when loading any
             FIDO authenticator-hosted keys, overriding the default of using
             the built-in USB HID support.

FILES
     ~/.ssh/id_dsa
     ~/.ssh/id_ecdsa
     ~/.ssh/id_ecdsa_sk
     ~/.ssh/id_ed25519
     ~/.ssh/id_ed25519_sk
     ~/.ssh/id_rsa
             Contains the DSA, ECDSA, authenticator-hosted ECDSA, Ed25519,
             authenticator-hosted Ed25519 or 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.


ATTRIBUTES
     See attributes(7) for descriptions of the following attributes:

     +---------------+--------------------------+
     |ATTRIBUTE TYPE |     ATTRIBUTE VALUE      |
     +---------------+--------------------------+
     |Availability   | network/ssh              |
     +---------------+--------------------------+
     |Stability      | Pass-through uncommitted |
     +---------------+--------------------------+

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 cre-
     ated OpenSSH.  Markus Friedl contributed the support for SSH protocol
     versions 1.5 and 2.0.



NOTES
     Source code for open source software components in Oracle Solaris can be
     found at https://www.oracle.com/downloads/opensource/solaris-source-code-
     downloads.html.

     This software was built from source available at https://github.com/ora-
     cle/solaris-userland.  The original community source was downloaded from
     https://mirrors.sonic.net/pub/OpenBSD/OpenSSH/porta-
     ble/openssh-8.4p1.tar.gz.

     Further information about this software can be found on the open source
     community website at https://www.openssh.com/.

BSD                              July 14, 2020                             BSD