ssh-add
—
adds RSA or DSA identities to the authentication agent
ssh-add |
[-cDdLlXx ] [-t
life] [file ...] |
ssh-add
adds RSA or DSA identities to the authentication
agent, ssh-agent(1). When run without arguments, it adds the
files ~/.ssh/id_rsa,
~/.ssh/id_dsa and
~/.ssh/identity. 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 the
SSH_ASKPASS
program mentioned below. Successful
confirmation is signaled by a zero exit status from the
SSH_ASKPASS
program, 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 will be removed. Otherwise, the argument list
will be interpreted as a list of paths to public key files and matching
keys will be removed from the agent. If no public key is found at a given
path, ssh-add
will append
.pub and retry.
-e
pkcs11
- Remove key provided by pkcs11.
-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 key provided by 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.
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
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/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_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 is 0 on success, 1 if the specified command fails, and 2 if
ssh-add
is unable to contact the authentication agent.
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.