PAM_SSH(8) BSD System Manager's Manual PAM_SSH(8)
NAME
pam_ssh -- authentication and session management with SSH private keys
SYNOPSIS
[service-name] module-type control-flag pam_ssh [options]
DESCRIPTION
The SSH authentication service module for PAM, pam_ssh provides functionality for two PAM categories: authentication and session management.
In terms of the module-type parameter, they are the ``auth'' and ``session'' features. It also provides null functions for the remaining
categories.
SSH Authentication Module
The SSH authentication component provides a function to verify the identity of a user (pam_sm_authenticate()), by prompting the user for a
passphrase and verifying that it can decrypt the target user's SSH key using that passphrase.
The following options may be passed to the authentication module:
debug syslog(3) debugging information at LOG_DEBUG level.
use_first_pass If the authentication module is not the first in the stack, and a previous module obtained the user's password, that password
is used to authenticate the user. If this fails, the authentication module returns failure without prompting the user for a
password. This option has no effect if the authentication module is the first in the stack, or if no previous modules
obtained the user's password.
try_first_pass This option is similar to the use_first_pass option, except that if the previously obtained password fails, the user is
prompted for another password.
keyfiles Specify the comma-separated list of files in $HOME/.ssh to check for SSH keys. The default is ``id_dsa,id_rsa,identity''.
nullok Allow empty passphrases.
SSH Session Management Module
The SSH session management component provides functions to initiate (pam_sm_open_session()) and terminate (pam_sm_close_session()) sessions.
The pam_sm_open_session() function starts an SSH agent, passing it any private keys it decrypted during the authentication phase, and sets
the environment variables the agent specifies. The pam_sm_close_session() function kills the previously started SSH agent by sending it a
SIGTERM.
The following options may be passed to the session management module:
debug syslog(3) debugging information at LOG_DEBUG level.
FILES
$HOME/.ssh/identity SSH1/OpenSSH RSA key
$HOME/.ssh/id_dsa OpenSSH DSA key
$HOME/.ssh2/id_rsa_* SSH2 RSA keys
$HOME/.ssh2/id_dsa_* SSH2 DSA keys
SEE ALSO
ssh-agent(1), syslog(3), pam.conf(5), pam(8)
AUTHORS
Andrew J. Korty <ajk@iu.edu> wrote pam_ssh. Dag-Erling Smorgrav wrote the original OpenPAM support code. Mark R V Murray wrote the original
version of this manual page.
BSD
November 26, 2001 BSD
