NAME
ssh-add —
adds private key identities to the
authentication agent
SYNOPSIS
ssh-add |
[-cDdkLlqvXx] [-E
fingerprint_hash] [-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, and
~/.ssh/id_ed25519. 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-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. -Efingerprint_hash- Specifies the hash algorithm used when displaying key fingerprints. Valid options are: “md5” and “sha256”. The default is “sha256”.
-epkcs11- 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.
-q- Be quiet after a successful operation.
-spkcs11- Add keys provided by the PKCS#11 shared library pkcs11.
-Tpubkey ...- Tests whether the private keys that correspond to the specified pubkey files are usable by performing sign and verify operations on each.
-tlife- 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).
-v- Verbose mode. Causes
ssh-addto print debugging messages about its progress. This is helpful in debugging problems. Multiple-voptions increase the verbosity. The maximum is 3. -X- Unlock the agent.
-x- Lock the agent with a password.
ENVIRONMENT
DISPLAY and SSH_ASKPASS- If
ssh-addneeds a passphrase, it will read the passphrase from the current terminal if it was run from a terminal. Ifssh-adddoes not have a terminal associated with it butDISPLAYandSSH_ASKPASSare set, it will execute the program specified bySSH_ASKPASS(by default “ssh-askpass”) and open an X11 window to read the passphrase. This is particularly useful when callingssh-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.) SSH_AUTH_SOCK- Identifies the path of a UNIX-domain socket used to communicate with the agent.
FILES
- ~/.ssh/id_dsa
- Contains the DSA authentication identity of the user.
- ~/.ssh/id_ecdsa
- Contains the ECDSA authentication identity of the user.
- ~/.ssh/id_ed25519
- Contains the Ed25519 authentication identity of the user.
- ~/.ssh/id_rsa
- Contains the 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.