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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>
<Directory /home/*/public_html/private>
AuthType Basic
AuthName MyPrivateFile
AuthUserFile /usr/local/apache/etc/.htpasswd-allusers
Satisfy All
Require file-owner
</Directory>
</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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