adds private key identities to the
ssh-add adds private key identities to the
ssh-agent(1). When run without arguments, it adds the files
~/.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,
asks for the passphrase from the user. The passphrase is read from the
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:
- 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.
- Deletes all identities from the agent.
- Instead of adding identities, removes identities from the agent. If
ssh-addhas 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-addwill append .pub and retry.
- Specifies the hash algorithm used when displaying key fingerprints. Valid options are: “md5” and “sha256”. The default is “sha256”.
- Remove keys provided by the PKCS#11 shared library pkcs11.
- When loading keys into or deleting keys from the agent, process plain private keys only and skip certificates.
- Lists public key parameters of all identities currently represented by the agent.
- Lists fingerprints of all identities currently represented by the agent.
- Add keys provided by the PKCS#11 shared library pkcs11.
- 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).
- Unlock the agent.
- Lock the agent with a password.
DISPLAY and SSH_ASKPASS
ssh-addneeds a passphrase, it will read the passphrase from the current terminal if it was run from a terminal. If
ssh-adddoes not have a terminal associated with it but
SSH_ASKPASSare 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-addfrom 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.)
- Identifies the path of a UNIX-domain socket used to communicate with the agent.
- Contains the protocol version 1 RSA authentication identity of the user.
- Contains the protocol version 2 DSA authentication identity of the user.
- Contains the protocol version 2 ECDSA authentication identity of the user.
- Contains the protocol version 2 Ed25519 authentication identity of the user.
- Contains the protocol version 2 RSA authentication identity of the user.
Identity files should not be readable by anyone but the user. Note
ssh-add ignores identity files if they are
accessible by others.
Exit status is 0 on success, 1 if the specified command fails, and
ssh-add is unable to contact the authentication
ssh(1), ssh-agent(1), ssh-askpass(1), ssh-keygen(1), sshd(8)
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.