                       Mod_Authz_Unixgroup version 1.2.0

	Original Author:  Jan Wolter
	        Website:  http://www.unixpapa.com/mod_authz_unixgroup/
	       Requires:  Apache 2.3 or later on a Unix server
	                   (for Apache 2.2 use mod_authz_unixgroup 1.0.x)

Mod_Authz_Unixgroup is a unix group access control modules for Apache.  If
you are having users authenticate with real Unix login ID over the net, using
something like my mod_authnz_external/pwauth combination, and you want to do
access control based on unix group membership, then mod_authz_unixgroup is
exactly what you need.

NOTE: Mod_Authz_Unixgroup 1.2.x and up require libbsd or the equivalent
bsd-standard group function support. See CHANGES or PR#55 for details.

Let's say that you were using this with mod_authnz_external and pwauth.  Your
.htaccess file for a protected directory would probably start with the
following directives:

    AuthType Basic
    AuthName mysite
    AuthBasicProvider external
    AuthExternal pwauth

That would cause mod_auth_basic and mod_authnz_external to do authentication
based on the Unix passwd database.  Mod_Authz_Unixgroup would come into play
if you wanted to further restrict access to specific Unix groups.  You might
append the following directive:

    Require unix-group staff admin

This would allow only access to accounts in the 'staff' or 'admin' unix groups.
You can alternately specify groups by their gid numbers instead of their names.

Or you could use mod_authz_unixgroup together with the standard apache module
mod_authz_owner to do something like:

    Require unix-file-group

This would allow access to the page, only the user was a member of the unix
group that owns the file.

Though it makes the most sense to use this with unix passwd authentication,
it can be used with other databases.  In that case it would grant access if,
(1) the name the user authenticated with exactly matched the name of a real
unix account on the server, and (2) that real unix account was in one of the
required groups.  However, I think this would be a pretty senseless way to
use this module.  I expect that it will really only be used by user of
mod_authnz_external/pwauth.

Some authentication modules, like mod_auth_kerb, use usernames that have
domains appended to them, like "whomever@krb.ncsu.edu".  In such cases,
mod_authz_unixgroup will take the part before the @-sign as the username
and ignore the rest.

Mod_authnz_external is available from:
   https://github.com/phokz/mod-auth-external

Pwauth is available from:
   http://code.google.com/p/pwauth/

It might also be possible to use this with mod_auth_shadow, especially if a
authn/authz version of that is ever released.
