1.\" Copyright (c) 2001 Mark R V Murray 2.\" All rights reserved. 3.\" Copyright (c) 2001 Networks Associates Technology, Inc. 4.\" All rights reserved. 5.\" 6.\" This software was developed for the FreeBSD Project by ThinkSec AS and 7.\" NAI Labs, the Security Research Division of Network Associates, Inc. 8.\" under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the 9.\" DARPA CHATS research program. 10.\" 11.\" Redistribution and use in source and binary forms, with or without 12.\" modification, are permitted provided that the following conditions 13.\" are met: 14.\" 1. Redistributions of source code must retain the above copyright 15.\" notice, this list of conditions and the following disclaimer. 16.\" 2. Redistributions in binary form must reproduce the above copyright 17.\" notice, this list of conditions and the following disclaimer in the 18.\" documentation and/or other materials provided with the distribution. 19.\" 3. The name of the author may not be used to endorse or promote 20.\" products derived from this software without specific prior written 21.\" permission. 22.\" 23.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 24.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 27.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33.\" SUCH DAMAGE. 34.\" 35.\" $FreeBSD$ 36.\" 37.Dd November 26, 2001 38.Dt PAM_SSH 8 39.Os 40.Sh NAME 41.Nm pam_ssh 42.Nd SSH PAM module 43.Sh SYNOPSIS 44.Op Ar service-name 45.Ar module-type 46.Ar control-flag 47.Pa pam_ssh 48.Op Ar options 49.Sh DESCRIPTION 50The 51SSH 52authentication service module for PAM, 53.Nm 54provides functionality for two PAM categories: 55authentication 56and session management. 57In terms of the 58.Ar module-type 59parameter, they are the 60.Dq Li auth 61and 62.Dq Li session 63features. 64It also provides null functions for the remaining categories. 65.Ss SSH Authentication Module 66The 67SSH 68authentication component 69provides a function to verify the identity of a user 70.Pq Fn pam_sm_authenticate , 71by prompting the user for a passphrase and verifying that it can 72decrypt the target user's SSH key using that passphrase. 73.Pp 74The following options may be passed to the authentication module: 75.Bl -tag -width ".Cm use_first_pass" 76.It Cm debug 77.Xr syslog 3 78debugging information at 79.Dv LOG_DEBUG 80level. 81.It Cm use_first_pass 82If the authentication module 83is not the first in the stack, 84and a previous module 85obtained the user's password, 86that password is used 87to authenticate the user. 88If this fails, 89the authentication module returns failure 90without prompting the user for a password. 91This option has no effect 92if the authentication module 93is the first in the stack, 94or if no previous modules 95obtained the user's password. 96.It Cm try_first_pass 97This option is similar to the 98.Cm use_first_pass 99option, 100except that if the previously obtained password fails, 101the user is prompted for another password. 102.El 103.Ss SSH Session Management Module 104The 105SSH 106session management component 107provides functions to initiate 108.Pq Fn pam_sm_open_session 109and terminate 110.Pq Fn pam_sm_close_session 111sessions. 112The 113.Fn pam_sm_open_session 114function starts an SSH agent, 115passing it any private keys it decrypted 116during the authentication phase, 117and sets the environment variables 118the agent specifies. 119The 120.Fn pam_sm_close_session 121function kills the previously started SSH agent 122by sending it a 123.Dv SIGTERM . 124.Pp 125The following options may be passed to the session management module: 126.Bl -tag -width ".Cm use_first_pass" 127.It Cm debug 128.Xr syslog 3 129debugging information at 130.Dv LOG_DEBUG 131level. 132.El 133.Sh FILES 134.Bl -tag -width ".Pa $HOME/.ssh2/id_dsa_*" -compact 135.It Pa $HOME/.ssh/identity 136SSH1/OpenSSH RSA key. 137.It Pa $HOME/.ssh/id_dsa 138OpenSSH DSA key. 139.It Pa $HOME/.ssh2/id_rsa_* 140SSH2 RSA keys. 141.It Pa $HOME/.ssh2/id_dsa_* 142SSH2 DSA keys. 143.El 144.Sh SEE ALSO 145.Xr ssh-agent 1 , 146.Xr syslog 3 , 147.Xr pam.conf 5 , 148.Xr pam 8 149