====== pam_require ======

This is a simple PAM account module. It is meant to be used together
with other modules! It allows you to require a special user or group
to access a service.

It's available at http://www.splitbrain.org/go/pam_require

===== Installation =====

You need the pam-devel files to compile it. In Debian do:
  
  # apt-get install libpam0g-dev

Compiling and installing __should__ be straight forward:

  $> ./configure
  $> make    
  $> su
  #> make install 

  
===== Usage =====

The module is an account module only! It has no usage as auth,
password or session module! 

**Please Note:** The Syntax has changed from Version 0.1

It accepts usernames or groupnames as parameter. Groupnames have to
be given with a leading @. Just have a look at the examples below:

This requires the user to be in a group called "dialin":

  account    required   pam_unix.so
  account    required   pam_require.so @dialin

This only allows user "joe" to login:
  
  account    required   pam_unix.so
  account    required   pam_require.so joe

Here either "joe" or members of the "dialin" group may login:

  account    required   pam_unix.so
  account    required   pam_require.so joe @dialin

Since version 0.3 you may let in everybody __except__ the named group
or user. This example keeps out members of the lusers group:

  account    required   pam_unix.so
  account    required   pam_require.so !@lusers

Since version 0.4 you can define users and groups with spaces, just use
colons instead of the spaces. You should always avoid using spaces in
usernames and groups but sometimes it is necessary (most times some kind of
interaction with Microsoft products is involved). The example lets in "Joe
Schmoe" and members of the "Windows Users" group.

  account    required   pam_unix.so
  account    required   pam_require.so Joe:Schmoe @Windows:Users

===== Bugs / Known Issues =====

Be careful with the negation (!). All parameters are logically OR'ed together
so if one statement is true access is granted. A simple example to explain -
Imagine this line:

  account    required   pam_unix.so
  account    required   pam_required.so !@lusers !@schmocks

This would let in all users in group schmocks that are not in group lusers.
To keep out both groups use two lines like this:

  account    required   pam_unix.so
  account    required   pam_required.so !@lusers
  account    required   pam_required.so !@schmocks

The module discards all standard parameter which are: debug, no_warn,
use_first_pass, try_first_pass, use_mapped_pass and expose_account. This means
two things: First these parameter doesn't change anything in pam_require's
behavior and second you can't have users with these names.

===== Thanks =====

To Jennifer Vesperman for her very helpful article "Writing PAM Modules"
at http://linux.oreillynet.com/pub/a/linux/2002/05/02/pam_modules.html

To Jens Chr. Bachem <j.bachem@travco.de> for the negation patch.

To Svein Olav Bjerkeset <svein.bjerkeset@vegvesen.no> for some hints what to
change for compiling on Solaris.

To Scipio <scipio@freemail.hu> for pointing out some errors in my code.

To Jon Severinsson <jon@severinsson.net> for adding the missing
primary group membership test

To Alexander E. Patrakov <patrakov@ums.usu.ru> for adding control files
to build Debian package

===== Feedback =====

I'm always open to suggestions or hints that help me make my C better.
I'm completely new to the whole autoconf/automake stuff so any tips on
this are greatly appreciated.

Just contact me at <andi@splitbrain.org> or visit pam_require in
the DokuWiki at http://www.splitbrain.org/dokuwiki/sw:pam_require

===== License =====

  pam_require - A simple PAM account module
  Copyright (C) 2003-2004 Andreas Gohr <a.gohr@web.de>
  
  This program is free software; you can redistribute it and/or
  modify it under the terms of the GNU General Public License
  as published by the Free Software Foundation; either version 2
  of the License, or (at your option) any later version.
  
  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.
  
  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.