Apache Module mod_authz_groupfile

Description:	Group authorization using plaintext files
Status:	Extension
Module Identifier:	authz_groupfile_module
Source File:	mod_authz_groupfile.c
Compatibility:	Available in Apache 2.0.44 and later

Summary

This module provides authorization capabilities so that authenticated users can be allowed or denied access to portions of the web site by group membership. Similar functionality is provided by mod_authz_dbm.

AuthGroupFile Directive

Description:	Sets the name of a text file containing the list of user groups for authentication
Syntax:	`AuthGroupFile file-path`
Context:	directory, .htaccess
Override:	AuthConfig
Status:	Extension
Module:	mod_authz_groupfile

The AuthGroupFile directive sets the name of a textual file containing the list of user groups for user authentication. File-path is the path to the group file. If it is not absolute (i.e., if it doesn't begin with a slash), it is treated as relative to the ServerRoot.

Each line of the group file contains a groupname followed by a colon, followed by the member usernames separated by spaces. Example:

mygroup: bob joe anne

Note that searching large text files is very inefficient; AuthDBMGroupFile should be used instead.

Security

Make sure that the AuthGroupFile is stored outside the document tree of the web-server; do not put it in the directory that it protects. Otherwise, clients will be able to download the AuthGroupFile.

AuthzGroupFileAuthoritative Directive

Description:	Sets whether authorization will be passed on to lower level modules
Syntax:	`AuthzGroupFileAuthoritative on\|off`
Default:	`AuthzGroupFileAuthoritative on`
Context:	directory, .htaccess
Override:	AuthConfig
Status:	Extension
Module:	mod_authz_groupfile

Setting the AuthzGroupFileAuthoritative directive explicitly to 'off' allows for authorization to be passed on to lower level modules (as defined in the Configuration and modules.c file if there is no userID or rule matching the supplied userID. If there is a userID and/or rule specified; the usual password and access checks will be applied and a failure will give an Authorization Required reply.

So if a valid Require directive applies to more than one module; then the first module will verify the credentials; and no access is passed on; regardless of the AuthzGroupFileAuthoritative setting.

By default, control is not passed on and an unknown userID or rule will result in an Authorization Required reply. Not setting it thus keeps the system secure and forces an NCSA compliant behaviour.

Security: Do consider the implications of allowing a user to allow fall-through in his .htaccess file; and verify that this is really what you want; Generally it is easier to just secure a single .htpasswd file, than it is to secure a database which might have more access interfaces.