mod_auth - Apache HTTP Server

Apache HTTP Server Version 2.0

Apache > HTTP Server > Documentation > Version 2.0 > Modules

# Apache Module mod_auth

Available Languages: en | ja

Description: | User authentication using text files
Status: | Base
Module Identifier: | auth_module
Source File: | mod_auth.c
Compatibility: | Available only in versions prior to 2.1

### Summary

This module allows the use of HTTP Basic Authentication to restrict access by looking up users in plain text password and group files. Similar functionality and greater scalability is provided by `mod_auth_dbm`. HTTP Digest Authentication is provided by `mod_auth_digest`.

### Directives

### See also

- `Require`
- `Satisfy`
- `AuthName`
- `AuthType`

## AuthAuthoritative Directive

Description: | Sets whether authorization and authentication are passed to lower level modules
Syntax: | `AuthAuthoritative On|Off`
Default: | `AuthAuthoritative On`
Context: | directory, .htaccess
Override: | AuthConfig
Status: | Base
Module: | mod_auth

Setting the `AuthAuthoritative` directive explicitly to `Off` allows for both authentication and authorization to be passed on to lower level modules (as defined in the `modules.c` files) 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 "Authentication Required" reply.

So if a userID appears in the database of more than one module; or 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 `AuthAuthoritative` setting.

A common use for this is in conjunction with one of the database modules; such as `mod_auth_dbm`, `mod_auth_msql`, and `mod_auth_anon`. These modules supply the bulk of the user credential checking; but a few (administrator) related accesses fall through to a lower level with a well protected `AuthUserFile`.

By default control is not passed on and an unknown userID or rule will result in an "Authentication 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 such as mSQL. Make sure that the `AuthUserFile` and the `AuthGroupFile` are stored outside the document tree of the web-server; do not put them in the directory that they protect. Otherwise, clients will be able to download the `AuthUserFile` and the `AuthGroupFile`.

## 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: | Base
Module: | mod_auth

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, 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` provides a much better performance.

### 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 may be able to download the `AuthGroupFile`.

## AuthUserFile Directive

Description: | Sets the name of a text file containing the list of users and passwords for authentication
Syntax: | `AuthUserFile file-path`
Context: | directory, .htaccess
Override: | AuthConfig
Status: | Base
Module: | mod_auth

The `AuthUserFile` directive sets the name of a textual file containing the list of users and passwords for user authentication. File-path is the path to the user 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 user file contains a username followed by a colon, followed by the encrypted password. If the same user ID is defined multiple times, `mod_auth` will use the first occurrence to verify the password.

The utility htpasswd which is installed as part of the binary distribution, or which can be found in `src/support`, is used to maintain this password file. See the man page for more details. In short:

Create a password file `Filename` with `username` as the initial ID. It will prompt for the password:

`htpasswd -c Filename username`

Add or modify `username2` in the password file `Filename`:

`htpasswd Filename username2`

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

### Security

Make sure that the `AuthUserFile` is stored outside the document tree of the web-server. Do not put it in the directory that it protects. Otherwise, clients may be able to download the `AuthUserFile`.

Available Languages: en | ja