mod_authz_sysgroup is an authorization module for Apache 2.2.x.

Features
    * Thread safe (you can use the worker or similar MPM safely).
    * Uses UNIX system groups (and thus supports anything the system can bind to, e.g. LDAP).
    * Supports both AND and OR group operations.
    * Can handle realm information (e.g. from mod_auth_kerb).



INSTALLATION:

To install, just extract and run:

make
make install



CONFIGURATION:

It works similar to mod_authz_groupfile (which was actually used as a template to create this module).
The main difference in the configuration syntax is a change which allows 'AND' group operations.

Add load the module in httpd.conf:
LoadModule authz_sysgroup_module modules/mod_authz_sysgroup.so

The option 'AuthzSysGroupAuthoritative' may be specified to allow access control to be passed along to
lower modules if the 'require group' fails.  (default is On).

The option 'AuthzSysGroupIgnoreSuffix' may be specified to ignore a suffix before checking anything.
This is intended to be used to strip realm information from something like mod_auth_kerb.

The special require line 'Require valid-system-user' will only check to make sure that the user is a
valid system user, no group membership will be checked.

CONFIGURATION EXAMPLES:

Using mod_auth_kerb (5.4) for authentication.  Allows elves to access the resource, along with any
chickens that are also a member of the ITAR group.  REMOTE_USER will end up in the form of 'username'.

<Location /secret>
    # mod_auth_kerb
    AuthType Kerberos
    AuthName "Kerberos Login"
    KrbAuthRealms EXAMPLE.COM
    KrbLocalUserMapping on

    # mod_authz_sysgroup
    Require group ITAR chickens
    Require group elves
</Location>


Using mod_auth_kerb for authentication.  Allows elves to access the resource, along with any chickens
that are also a member of the ITAR group.  REMOTE_USER will end up in the form of 'username@EXAMPLE.COM'.

<Location /secret>
    # mod_auth_kerb
    AuthType Kerberos
    AuthName "Kerberos Login"
    KrbAuthRealms EXAMPLE.COM

    # mod_authz_sysgroup
    AuthzSysGroupIgnoreSuffix @EXAMPLE.COM
    Require group ITAR chickens
    Require group elves
</Location>


A more complicated example using 2 kerberos realms, the system groups, and another ldap server.
This allows for having the system bound to an MS active directory domain using samba winbind,
and allowing apache to authenticate against that along with another kerberos and ldap authentication
system.  This could also support other combinations as well.  REMOTE_USER will end up in the form
of 'username@AD.EXAMPLE.COM' or 'username@UNIX.EXAMPLE.COM'.

This assumes that the 'cn' attribute in ldap is set to something like 'username@UNIX.EXAMPLE.COM'.
Note that if you do something like this, it is advisable to either make sure that no username
exists in both realms, or to disable automatic account locking from login failures.  This is
because some authentations will fail naturally (when skipping over the 1st realm and going to the 2nd),
and we don't want some users getting their account locked out due to this behavior.

Note that in my own tests, 'KrbServiceName Any' causes a segfault.  If you experience the same
issue, you can use 'KrbVerifyKDC off' instead to workaround the problem.  Of course this is less
secure.

<Location /secret>
    # mod_auth_kerb
    AuthType Kerberos
    AuthName "AD or UNIX"
    KrbAuthRealms AD.EXAMPLE.COM UNIX.EXAMPLE.COM
    KrbServiceName Any

    # mod_authz_sysgroup
    AuthzSysGroupIgnoreSuffix @AD.EXAMPLE.COM
    AuthzSysGroupAuthoritative off
    Require group chickens

    # mod_authnz_ldap
    AuthLDAPURL ldap://127.0.0.1/ou=people,dc=unix,dc=example,dc=com?cn
    AuthzLDAPAuthoritative off
    Require ldap-filter &(employeeType=turkey)
</Location>


A similar configuration as above, but allowing any valid user from AD.EXAMPLE.COM and a subset of
users from UNIX.EXAMPLE.COM.

<Location /secret>
    # mod_auth_kerb
    AuthType Kerberos
    AuthName "AD or UNIX"
    KrbAuthRealms AD.EXAMPLE.COM UNIX.EXAMPLE.COM
    KrbServiceName Any

    # mod_authz_sysgroup
    AuthzSysGroupIgnoreSuffix @AD.EXAMPLE.COM
    AuthzSysGroupAuthoritative off
    Require valid-system-user

    # mod_authnz_ldap
    AuthLDAPURL ldap://127.0.0.1/ou=people,dc=unix,dc=example,dc=com?cn
    AuthzLDAPAuthoritative off
    Require ldap-filter &(employeeType=turkey)
</Location>