1.\" $NetBSD: pam.8,v 1.3 2005/03/14 10:44:02 wiz Exp $ 2.\" 3.\" Copyright (c) 2005 The NetBSD Foundation, Inc. 4.\" All rights reserved. 5.\" 6.\" This code is derived from software contributed to The NetBSD Foundation 7.\" by Jason R. Thorpe. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 3. All advertising materials mentioning features or use of this software 18.\" must display the following acknowledgement: 19.\" This product includes software developed by the NetBSD 20.\" Foundation, Inc. and its contributors. 21.\" 4. Neither the name of The NetBSD Foundation nor the names of its 22.\" contributors may be used to endorse or promote products derived 23.\" from this software without specific prior written permission. 24.\" 25.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 26.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 27.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 29.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35.\" POSSIBILITY OF SUCH DAMAGE. 36.\" 37.Dd February 28, 2005 38.Dt PAM 8 39.Os 40.Sh NAME 41.Nm pam 42.Nd Pluggable Authentication Modules framework 43.Sh DESCRIPTION 44The Pluggable Authentication Modules 45.Pq PAM 46framework is a system of libraries that perform authentication tasks for 47services and applications. 48Applications that use the PAM API may have their authentication behavior 49configured by the system administrator though the use of the service's 50PAM configuration file. 51.Pp 52PAM modules provide four classes of functionality: 53.Bl -tag -width password 54.It account 55Account verification services such as password expiration and access control. 56.It auth 57Authentication services. 58This usually takes the form of a challenge-response conversation. 59However, PAM can also support, with appropriate hardware support, biometric 60devices, smart-cards, and so forth. 61.It password 62Password 63.Pq or, more generally, authentication token 64change and update services. 65.It session 66Session management services. 67These are tasks that are performed before access to a service is granted 68and after access to a service is withdrawn. 69These may include updating activity logs or setting up and tearing down 70credential forwarding agents. 71.El 72.Pp 73A primary feature of PAM is the notion of 74.Dq stacking 75different modules together to form a processing chain for the task. 76This allows fairly precise control over how a particular authentication 77task is performed, and under what conditions. 78PAM module configurations may also inherit stacks from other module 79configurations, providing some degree of centralized administration. 80.Sh SEE ALSO 81.Xr login 1 , 82.Xr passwd 1 , 83.Xr su 1 , 84.Xr pam 3 , 85.Xr pam.conf 5 , 86.Xr pam_chroot 8 , 87.Xr pam_deny 8 , 88.Xr pam_echo 8 , 89.Xr pam_exec 8 , 90.Xr pam_ftpusers 8 , 91.Xr pam_group 8 , 92.Xr pam_guest 8 , 93.Xr pam_krb5 8 , 94.Xr pam_ksu 8 , 95.Xr pam_lastlog 8 , 96.Xr pam_login_access 8 , 97.Xr pam_nologin 8 , 98.Xr pam_permit 8 , 99.Xr pam_radius 8 , 100.Xr pam_rhosts 8 , 101.Xr pam_rootok 8 , 102.Xr pam_securetty 8 , 103.Xr pam_self 8 , 104.Xr pam_skey 8 , 105.Xr pam_ssh 8 , 106.Xr pam_unix 8 107.Sh HISTORY 108The Pluggable Authentication Module framework was originally developed 109by SunSoft, described in DCE/OSF-RFC 86.0, and first deployed in Solaris 2.6. 110It was later incorporated into the X/Open Single Sign-On Service 111.Pq XSSO 112Pluggable Authentication Modules specifiation. 113.Pp 114The Pluggable Authentication Module framework first appeared in 115.Nx 3.0 . 116