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      <h3>Apache HTTP Server Version 1.3</h3>
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    <h1 align="CENTER">Module mod_auth</h1>

    <p>This module provides for user authentication using text
    files.</p>

    <p><a href="module-dict.html#Status"
    rel="Help"><strong>Status:</strong></a> Base<br />
     <a href="module-dict.html#SourceFile"
    rel="Help"><strong>Source File:</strong></a> mod_auth.c<br />
     <a href="module-dict.html#ModuleIdentifier"
    rel="Help"><strong>Module Identifier:</strong></a>
    auth_module</p>

    <h2>Summary</h2>

    <p>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 <a href="mod_auth_dbm.html">mod_auth_dbm</a> and <a
    href="mod_auth_db.html">mod_auth_db</a>. HTTP Digest
    Authentication is provided by <a
    href="mod_auth_digest.html">mod_auth_digest</a>.</p>

    <p><b>Note that these credential-based security mechanisms are
    only as strong as your Web server's security. As a rule, they
    are <i>not</i> as strong as the operating system's own security
    system.</b></p>

    <h2>Directives</h2>

    <ul>
      <li><a href="#authgroupfile">AuthGroupFile</a></li>

      <li><a href="#authuserfile">AuthUserFile</a></li>

      <li><a href="#authauthoritative">AuthAuthoritative</a></li>
    </ul>

    <p>See also: <a href="core.html#require">require</a>, <a
    href="core.html#satisfy">satisfy</a>, and <a
    href="#require">mod_auth require keywords</a>.</p>
    <hr />

    <h2><a id="require" name="require"><code>mod_auth</code>
    Require Keywords</a></h2>

    <p>The <code>mod_auth</code> module supports the following
    keywords that can be given to the <a
    href="core.html#require">Require</a> directive:</p>

    <dl compact="compact">
      <dt><code>user <i>username</i> [...]</code></dt>

      <dd>The supplied username and password must be in the <a
      href="#authuserfile">AuthUserFile</a> database, and the
      username must also be one of those listed on the Require
      directive.</dd>

      <dt><code>group <i>groupname</i> [...]</code></dt>

      <dd>The supplied username and password must be in the <a
      href="#authuserfile">AuthUserFile</a> database, and the
      username must also be a member of one of the named groups in
      the <a href="#authgroupfile">AuthGroupFile</a> database.</dd>

      <dt><code>valid-user</code></dt>

      <dd>The supplied username and password must be in the <a
      href="#authuserfile">AuthUserFile</a> database. Any valid
      username from that file will be allowed.</dd>

      <dt><code>file-owner</code></dt>

      <dd>[Available after Apache 1.3.20] The supplied username and
      password must be in the <a
      href="#authuserfile">AuthUserFile</a> database, and the
      username must also match the system's name for the owner of
      the file being requested. That is, if the operating system
      say the requested file is owned by <code>jones</code>, then
      the username used to access it through the Web must be
      <code>jones</code> as well.</dd>

      <dt><code>file-group</code></dt>

      <dd>[Available after Apache 1.3.20] The supplied username and
      password must be in the <a
      href="#authuserfile">AuthUserFile</a> database, the name of
      the group that owns the file must be in the <a
      href="#authgroupfile">AuthGroupFile</a> database, and the
      username must be a member of that group. For example, if the
      operating system says the requested file is owned by group
      <code>accounts</code>, the group <code>accounts</code> must
      be in the AuthGroupFile database and the username used in the
      request must be a member of that group.</dd>
    </dl>
    <hr />

    <h2><a id="example" name="example">Example of <code>Require
    file-owner</code></a></h2>

    <p>Consider a multi-user system running the Apache Web server,
    with each user having his or her own files in
    <code>~/public_html/private</code>. Assuming that there is a
    single AuthUserFile database that lists all of their usernames,
    and that their Web usernames match the ones that actually own
    the files on the server, then the following stanza would allow
    only the user himself access to his own files. User
    <code>jones</code> would not be allowed to access files in
    <code>/home/smith/public_html/private</code> unless they were
    owned by <code>jones</code> instead of <code>smith</code>.</p>
<pre>
    &lt;Directory /home/*/public_html/private&gt;
        AuthType Basic
        AuthName MyPrivateFile
        AuthUserFile /usr/local/apache/etc/.htpasswd-allusers
        Satisfy All
        Require file-owner
    &lt;/Directory&gt;
</pre>
    <hr />

    <h2><a id="authgroupfile"
    name="authgroupfile">AuthGroupFile</a> directive</h2>
    <a href="directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> AuthGroupFile
    <em>file-path</em><br />
     <a href="directive-dict.html#Context"
    rel="Help"><strong>Context:</strong></a> directory,
    .htaccess<br />
     <a href="directive-dict.html#Override"
    rel="Help"><strong>Override:</strong></a> AuthConfig<br />
     <a href="directive-dict.html#Status"
    rel="Help"><strong>Status:</strong></a> Base<br />
     <a href="directive-dict.html#Module"
    rel="Help"><strong>Module:</strong></a> mod_auth 

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

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

    <blockquote>
      <code>mygroup: bob joe anne</code>
    </blockquote>
    Note that searching large text files is <em>very</em>
    inefficient; <a
    href="mod_auth_dbm.html#authdbmgroupfile">AuthDBMGroupFile</a>
    should be used instead. 

    <p>Security: make sure that the AuthGroupFile is stored outside
    the document tree of the web-server; do <em>not</em> put it in
    the directory that it protects. Otherwise, clients will be able
    to download the AuthGroupFile.</p>

    <p>See also <a href="core.html#authname">AuthName</a>, <a
    href="core.html#authtype">AuthType</a> and <a
    href="#authuserfile">AuthUserFile</a>.</p>
    <hr />

    <h2><a id="authuserfile" name="authuserfile">AuthUserFile</a>
    directive</h2>
    <a href="directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> AuthUserFile
    <em>file-path</em><br />
     <a href="directive-dict.html#Context"
    rel="Help"><strong>Context:</strong></a> directory,
    .htaccess<br />
     <a href="directive-dict.html#Override"
    rel="Help"><strong>Override:</strong></a> AuthConfig<br />
     <a href="directive-dict.html#Status"
    rel="Help"><strong>Status:</strong></a> Base<br />
     <a href="directive-dict.html#Module"
    rel="Help"><strong>Module:</strong></a> mod_auth 

    <p>The AuthUserFile directive sets the name of a textual file
    containing the list of users and passwords for user
    authentication. <em>File-path</em> is the path to the user
    file. If it is not absolute (<em>i.e.</em>, if it doesn't begin
    with a slash), it is treated as relative to the ServerRoot.</p>

    <p>Each line of the user file contains a username followed by a
    colon, followed by the <code>crypt()</code> encrypted password.
    The behavior of multiple occurrences of the same user is
    undefined.</p>

    <p>The utility <a href="../programs/htpasswd.html">htpasswd</a>
    which is installed as part of the binary distribution, or which
    can be found in <code>src/support</code>, is used to maintain
    this password file. See the <code>man</code> page for more
    details. In short</p>

    <blockquote>
      <code>htpasswd -c Filename username</code><br />
       Create a password file 'Filename' with 'username' as the
      initial ID. It will prompt for the password. <code>htpasswd
      Filename username2</code><br />
       Adds or modifies in password file 'Filename' the 'username'.
    </blockquote>

    <p>Note that searching large text files is <em>very</em>
    inefficient; <a
    href="mod_auth_dbm.html#authdbmuserfile">AuthDBMUserFile</a>
    should be used instead.</p>

    <dl>
      <dt><b>Security:</b></dt>

      <dd>Make sure that the AuthUserFile is stored outside the
      document tree of the web-server; do <em>not</em> put it in
      the directory that it protects. Otherwise, clients may be
      able to download the AuthUserFile.</dd>

      <dd>Also be aware that null usernames are permitted, and null
      passwords as well (through Apache 1.3.20). If your
      AuthUserFile includes a line containing only a colon (':'), a
      '<code>Require valid-user</code>' will allow access if both
      the username and password in the credentials are
      omitted.</dd>
    </dl>
    See also <a href="core.html#authname">AuthName</a>, <a
    href="core.html#authtype">AuthType</a> and <a
    href="#authgroupfile">AuthGroupFile</a>. 
    <hr />

    <h2><a id="authauthoritative"
    name="authauthoritative">AuthAuthoritative</a> directive</h2>
    <a href="directive-dict.html#Syntax"
    rel="Help"><strong>Syntax:</strong></a> AuthAuthoritative
    on|off<br />
     <a href="directive-dict.html#Default"
    rel="Help"><strong>Default:</strong></a>
    <code>AuthAuthoritative on</code><br />
     <a href="directive-dict.html#Context"
    rel="Help"><strong>Context:</strong></a> directory,
    .htaccess<br />
     <a href="directive-dict.html#Override"
    rel="Help"><strong>Override:</strong></a> AuthConfig<br />
     <a href="directive-dict.html#Status"
    rel="Help"><strong>Status:</strong></a> Base<br />
     <a href="directive-dict.html#Module"
    rel="Help"><strong>Module:</strong></a> mod_auth 

    <p>Setting the AuthAuthoritative directive explicitly to
    <strong>'off'</strong> allows for both authentication and
    authorization to be passed on to lower level modules (as
    defined in the <code>Configuration</code> and
    <code>modules.c</code> files) if there is <strong>no
    userID</strong> or <strong>rule</strong> 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.</p>

    <p>So if a userID appears in the database of more than one
    module; or if a valid <code>Require</code> 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.</p>

    <p>A common use for this is in conjunction with one of the
    database modules; such as <a
    href="mod_auth_db.html"><code>mod_auth_db.c</code></a>, <a
    href="mod_auth_dbm.html"><code>mod_auth_dbm.c</code></a>,
    <code>mod_auth_msql.c</code>, and <a
    href="mod_auth_anon.html"><code>mod_auth_anon.c</code></a>.
    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.</p>

    <p><a href="directive-dict.html#Default"
    rel="Help"><strong>Default:</strong></a> 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 behavior.</p>

    <p>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 is stored outside the
    document tree of the web-server; do <em>not</em> put it in the
    directory that it protects. Otherwise, clients will be able to
    download the AuthUserFile.</p>

    <p>See also <a href="core.html#authname">AuthName</a>, <a
    href="core.html#authtype">AuthType</a> and <a
    href="#authgroupfile">AuthGroupFile</a>.</p>

    <p>    <hr />

    <h3 align="CENTER">Apache HTTP Server Version 1.3</h3>
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