SSH-ADD(1) BSD General Commands Manual SSH-ADD(1)
ssh-add - adds RSA or DSA identities to the authentication agent
ssh-add [-cDdLlXx] [-t life] [file ...]
ssh-add -s reader
ssh-add -e reader
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 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 the SSH_ASKPASS program mentioned below. Successful confirma-
tion is signaled by a zero exit status from the SSH_ASKPASS pro-
gram, rather than text entered into the requester.
-D Deletes all identities from the agent.
-d Instead of adding the identity, removes the identity from the
Remove key in smartcard reader.
-L Lists public key parameters of all identities currently repre-
sented by the agent.
-l Lists fingerprints of all identities currently represented by the
Add key in smartcard reader.
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).
-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.)
Identifies the path of a unix-domain socket used to communicate
with the agent.
The reseeding of the OpenSSL random generator is usually done
from /dev/urandom. If the SSH_USE_STRONG_RNG environment vari-
able is set to value other than 0 the OpenSSL random generator is
reseeded from /dev/random. The number of bytes read is defined
by the SSH_USE_STRONG_RNG value. Minimum is 6 bytes. This set-
ting is not recommended on the computers without the hardware
random generator because insufficient entropy causes the connec-
tion to be blocked until enough entropy is available.
Contains the protocol version 1 RSA authentication identity of
Contains the protocol version 2 DSA authentication identity of
Contains the protocol version 2 RSA authentication identity of
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-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 cre-
ated OpenSSH. Markus Friedl contributed the support for SSH protocol
versions 1.5 and 2.0.
BSD September 25, 1999 BSD