Provided by: openssh-client_8.2p1-4_amd64
ssh-add — adds private key identities to the OpenSSH authentication agent
ssh-add [-cDdKkLlqvXx] [-E fingerprint_hash] [-S provider] [-t life] [file ...] ssh-add -s pkcs11 ssh-add -e pkcs11 ssh-add -T pubkey ...
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 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 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 represented 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 specified 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.
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. 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.
~/.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 is 0 on success, 1 if the specified command fails, and 2 if ssh-add is unable to contact the authentication agent.
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.