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<h1 align="CENTER">Module mod_auth_ldap</h1>
<p>This is an authentication module that allows Apache to
authenticate HTTP clients using user entries in an LDAP
directory.</p>
rel="Help"><strong>Status:</strong></a> Extension<br />
<a href="module-dict.html#SourceFile"
<a href="module-dict.html#ModuleIdentifier"
rel="Help"><strong>Module Identifier:</strong></a>
ldap_module<br />
<a href="module-dict.html#Compatibility"
rel="Help"><strong>Compatibility:</strong></a> Available in
Apache 2.0 and later.</p>
<h2>Summary</h2>
<p>mod_auth_ldap supports the following features:</p>
<ul>
<li>Known to support the <a
and 2.x), and the <a
href="http://www.iplanet.com/downloads/developer/">iPlanet
(Netscape)</a> SDK.</li>
<li>Complex authorization policies can be implemented by
representing the policy with LDAP filters.</li>
<li>Support for Microsoft FrontPage allows FrontPage users to
control access to their webs, while retaining LDAP for user
authentication.</li>
<li>Uses extensive caching of LDAP operations via <a
<li>Support for LDAP over SSL (requires the Netscape SDK) or
TLS (requires the OpenLDAP 2.x SDK).</li>
</ul>
<h2>Directives</h2>
<ul>
<li><a
href="#AuthLDAPAuthoritative">AuthLDAPAuthoritative</a></li>
<li><a href="#AuthLDAPBindDN">AuthLDAPBindDN</a></li>
<li><a
href="#AuthLDAPBindPassword">AuthLDAPBindPassword</a></li>
<li><a
href="#AuthLDAPCompareDNOnServer">AuthLDAPCompareDNOnServer</a></li>
<li><a
href="#AuthLDAPDereferenceAliases">AuthLDAPDereferenceAliases</a></li>
<li><a href="#AuthLDAPEnabled">AuthLDAPEnabled</a></li>
<li><a
href="#AuthLDAPFrontPageHack">AuthLDAPFrontPageHack</a></li>
<li><a
href="#AuthLDAPGroupAttribute">AuthLDAPGroupAttribute</a></li>
<li><a
href="#AuthLDAPGroupAttributeIsDN">AuthLDAPGroupAttributeIsDN</a></li>
<li><a
href="#AuthLDAPRemoteUserIsDN">AuthLDAPRemoteUserIsDN</a></li>
<li><a href="#AuthLDAPStartTLS">AuthLDAPStartTLS</a></li>
<li><a href="#AuthLDAPUrl">AuthLDAPUrl</a></li>
</ul>
<h2>Contents</h2>
<ul>
<li>
<a href="#operation">Operation</a>
<ul>
<li><a href="#authenphase">The Authentication
Phase</a></li>
<li><a href="#authorphase">The Authorization
Phase</a></li>
</ul>
</li>
<li>
<a href="#requiredirectives">The require Directives</a>
<ul>
<li><a href="#reqvaliduser">require valid-user</a></li>
<li><a href="#requser">require user</a></li>
<li><a href="#reqgroup">require group</a></li>
<li><a href="#reqdn">require dn</a></li>
</ul>
</li>
<li><a href="#examples">Examples</a></li>
<li><a href="#usingtls">Using TLS</a></li>
<li><a href="#usingssl">Using SSL</a></li>
<li>
<a href="#frontpage">Using Microsoft FrontPage with
mod_auth_ldap</a>
<ul>
<li><a href="#howitworks">How It Works</a></li>
<li><a href="#fpcaveats">Caveats</a></li>
</ul>
</li>
</ul>
<h2><a id="operation" name="operation">Operation</a></h2>
<p>There are two phases in granting access to a user. The first
phase is authentication, in which mod_auth_ldap verifies that
the user's credentials are valid. This also called the
authorization, in which mod_auth_ldap determines if the
authenticated user is allowed access to the resource in
question. This is also known as the <em><b>compare</b></em>
phase.</p>
<h3><a id="authenphase" name="authenphase">The Authentication
Phase</a></h3>
<p>During the authentication phase, mod_auth_ldap searches for
an entry in the directory that matches the username that the
HTTP client passes. If a single unique match is found, then
mod_auth_ldap attempts to bind to the directory server using
the DN of the entry plus the password provided by the HTTP
client. Because it does a search, then a bind, it is often
<ol>
<li>Generate a search filter by combining the attribute and
filter provided in the <a
href="#AuthLDAPURL"><tt>AuthLDAPURL</tt></a> directive with
the username passed by the HTTP client.</li>
<li>Search the directory using the generated filter. If the
search does not return exactly one entry, deny or decline
access.</li>
<li>Fetch the distinguished name of the entry retrieved from
the search and attempt to bind to the LDAP server using the
DN and the password passed by the HTTP client. If the bind is
unsuccessful, deny or decline access.</li>
</ol>
phase</p>
<table border="0" bgcolor="#ffffff">
<tr valign="top">
<td colspan="1" align="left"><a
href="#AuthLDAPURL">AuthLDAPURL</a> </td>
<td colspan="1" align="left">Specifies the LDAP server, the
base DN, the attribute to use in the search, as well as the
extra search filter to use.</td>
</tr>
<tr valign="top">
<td colspan="1" align="left"><a
href="#AuthLDAPBindDN">AuthLDAPBindDN</a> </td>
<td colspan="1" align="left">An optional DN to bind with
during the search phase.</td>
</tr>
<tr valign="top">
<td colspan="1" align="left"><a
href="#AuthLDAPBindPassword">AuthLDAPBindPassword</a> </td>
<td colspan="1" align="left">An optional password to bind
with during the search phase.</td>
</tr>
</table>
<h3><a id="authorphase" name="authorphase">The Authorization
Phase</a></h3>
<p>During the authorization phase, mod_auth_ldap attempts to
determine if the user is authorized to access the resource.
Many of these checks require mod_auth_ldap to do a compare
operation on the LDAP server. This is why this phase is often
referred to as the compare phase. mod_auth_ldap accepts the
following <a href="#requiredirectives"><tt>require</tt>
directives</a> to determine if the credentials are
acceptable:</p>
<ul>
<li>Grant access if there is a <a href="#requser"><tt>require
valid-user</tt></a> directive.</li>
<li>Grant access if there is a <a
href="#reqgroup"><tt>require user</tt></a> directive, and the
username in the directive matches the username passed by the
client.</li>
<li>Grant access if there is a <a href="#reqdn"><tt>require
dn</tt></a> directive, and the DN in the directive matches
the DN fetched from the LDAP directory.</li>
<li>Grant access if there is a <a
href="#reqgroup"><tt>require group</tt></a> directive, and
the DN fetched from the LDAP directory (or the username
passed by the client) occurs in the LDAP group.</li>
<li>otherwise, deny or decline access</li>
</ul>
<p>mod_auth_ldap uses the following directives during the
compare phase:</p>
<table border="0" bgcolor="#ffffff">
<tr>
<td><a href="#AuthLDAPURL"><tt>AuthLDAPURL</tt></a> </td>
<td colspan="1" align="left">The attribute specified in the
URL is used in compare operations for the <tt>require
user</tt> operation.</td>
</tr>
<tr>
<td><a
href="#AuthLDAPCompareDNOnServer"><tt>AuthLDAPCompareDNOnServer</tt></a>
</td>
<td colspan="1" align="left">Determines the behavior of the
<tt>require dn</tt> directive.</td>
</tr>
<tr>
<td><a
href="#AuthLDAPGroupAttribute"><tt>AuthLDAPGroupAttribute</tt></a>
</td>
<td colspan="1" align="left">Determines the attribute to
use for comparisons in the <tt>require group</tt>
directive.</td>
</tr>
<tr>
<td><a
href="#AuthLDAPGroupAttributeIsDN"><tt>AuthLDAPGroupAttributeIsDN</tt></a>
</td>
<td colspan="1" align="left">Specifies whether to use the
user DN or the username when doing comparisons for the
<tt>require group</tt> directive.</td>
</tr>
</table>
<h2><a id="requiredirectives" name="requiredirectives">The
require Directives</a></h2>
<p>Apache's <tt>require</tt> directives are used during the
authorization phase to ensure that a user is allowed to access
a resource.</p>
<h3><a id="reqvaliduser" name="reqvaliduser">require
valid-user</a></h3>
<p>If this directive exists, mod_auth_ldap grants access to any
phase.</p>
<h3><a id="requser" name="requser">require user</a></h3>
<p>The <tt>require user</tt> directive specifies what usernames
can access the resource. Once mod_auth_ldap has retrieved a
unique DN from the directory, it does an LDAP compare operation
using the username specified in the <tt>require user</tt> to
see if that username is part of the just-fetched LDAP entry.
Multiple users can be granted access by putting multiple
usernames on the line, separated with spaces. If a username has
a space in it, then it must be the only user on the line. In
this case, multiple users can be granted access by using
multiple <tt>require user</tt> directives, with one user per
line. For example, with a <tt>AuthLDAPURL</tt> of
searches), the following require directives could be used to
restrict access:</p>
<pre>
require user Barbara Jenson
require user Fred User
require user Joe Manager
</pre>
<p>Because of the way that mod_auth_ldap handles this
directive, Barbara Jenson could sign on as <i>Barbara
Jenson</i>, <i>Babs Jenson</i> or any other <tt>cn</tt> that
she has in her LDAP entry. Only the single <tt>require
user</tt> line is needed to support all values of the attribute
in the user's entry.</p>
<p>If the <tt>uid</tt> attribute was used instead of the
<tt>cn</tt> attribute in the URL above, the above three lines
could be condensed to</p>
<pre>
require user bjenson fuser jmanager
</pre>
<h3><a id="reqgroup" name="reqgroup">require group</a></h3>
<p>This directive specifies an LDAP group whose members are
allowed access. It takes the distinguished name of the LDAP
group. For example, assume that the following entry existed in
the LDAP directory:</p>
<pre>
dn: cn=Administrators, o=Airius
objectClass: groupOfUniqueNames
uniqueMember: cn=Barbara Jenson, o=Airius
uniqueMember: cn=Fred User, o=Airius
</pre>
<p>The following directive would grant access to both Fred and
Barbara:</p>
<pre>
require group cn=Administrators, o=Airius
</pre>
<p>Behavior of this directive is modified by the <a
href="#AuthLDAPGroupAttribute"><tt>AuthLDAPGroupAttribute</tt></a>
and <a
href="#AuthLDAPGroupAttributeIsDN"><tt>AuthLDAPGroupAttributeIsDN</tt></a>
directives.</p>
<h3><a id="reqdn" name="reqdn">require dn</a></h3>
<p>The <tt>require dn</tt> directive allows the administrator
to grant access based on distinguished names. It specifies a DN
that must match for access to be granted. If the distinguished
name that was retrieved from the directory server matches the
distinguished name in the <tt>require dn</tt>, then
authorization is granted.</p>
<p>The following directive would grant access to a specific
DN:</p>
<pre>
require dn cn=Barbara Jenson, o=Airius
</pre>
<p>Behavior of this directive is modified by the <a
href="#AuthLDAPCompareDNOnServer"><tt>AuthLDAPCompareDNOnServer</tt></a>
directive.</p>
<h2><a id="examples" name="examples">Examples</a></h2>
<ul>
<li>
Grant access to anyone who exists in the LDAP directory,
using their UID for searches.
<pre>
require valid-user
</pre>
</li>
<li>
The next example is the same as above; but with the fields
that have useful defaults omitted. Also, note the use of a
redundant LDAP server.
<pre>
require valid-user
</pre>
</li>
<li>
The next example is similar to the previous one, but is
uses the common name instead of the UID. Note that this
could be problematical if multiple people in the directory
share the same <tt>cn</tt>, because a search on <tt>cn</tt>
<em><b>must</b></em> return exactly one entry. That's why
this approach is not recommended: it's a better idea to
choose an attribute that is guaranteed unique in your
directory, such as <tt>uid</tt>.
<pre>
AuthLDAPURL ldap://ldap.airius.com/ou=People, o=Airius?cn
require valid-user
</pre>
</li>
<li>
Grant access to anybody in the Administrators group. The
users must authenticate using their UID.
<pre>
AuthLDAPURL ldap://ldap.airius.com/o=Airius?uid
require group cn=Administrators, o=Airius
</pre>
</li>
<li>
The next example assumes that everyone at Airius who
carries an alphanumeric pager will have an LDAP attribute
of <tt>qpagePagerID</tt>. The example will grant access
only to people (authenticated via their UID) who have
alphanumeric pagers:
<pre>
AuthLDAPURL ldap://ldap.airius.com/o=Airius?uid??(qpagePagerID=*)
require valid-user
</pre>
</li>
<li>
<p>The next example demonstrates the power of using filters
to accomplish complicated administrative requirements.
Without filters, it would have been necessary to create a
new LDAP group and ensure that the group's members remain
synchronized with the pager users. This becomes trivial
with filters. The goal is to grant access to anyone who has
a filter, plus grant access to Joe Manager, who doesn't
have a pager, but does need to access the same
resource:</p>
<pre>
AuthLDAPURL ldap://ldap.airius.com/o=Airius?uid??(|(qpagePagerID=*)(uid=jmanager))
require valid-user
</pre>
<p>This last may look confusing at first, so it helps to
evaluate what the search filter will look like based on who
connects, as shown below. The text in blue is the part that
is filled in using the attribute specified in the URL. The
text in red is the part that is filled in using the filter
specified in the URL. The text in green is filled in using
the information that is retrieved from the HTTP client. If
Fred User connects as <i>fuser</i>, the filter would look
like</p>
<p><tt>(&<font
color="red">(|(qpagePagerID=*)(uid=jmanager))</font>(<font
color="blue">uid</font>=<font
color="green">fuser</font>))</tt></p>
<p>The above search will only succeed if <i>fuser</i> has a
pager. When Joe Manager connects as <i>jmanager</i>, the
filter looks like</p>
<p><tt>(&<font
color="red">(|(qpagePagerID=*)(uid=jmanager))</font>(<font
color="blue">uid</font>=<font
color="green">jmanager</font>))</tt></p>
<p>The above search will succeed whether <i>jmanager</i>
has a pager or not.</p>
</li>
</ul>
<h2><a id="usingtls" name="usingtls">Using TLS</a></h2>
<p>To use TLS, simply set the <tt>AuthLDAPStartTLS</tt> to on.
Nothing else needs to be done (other than ensure that your LDAP
server is configured for TLS).</p>
<h2><a id="usingssl" name="usingssl">Using SSL</a></h2>
SDK, it will not talk to any SSL server unless that server has
a certificate signed by a known Certificate Authority. As part
of the configuration mod_auth_ldap needs to be told where it
can find a database containing the known CAs. This database is
database. The easiest way to get this file is to start up a
fresh copy of Netscape, and grab the resulting
<p>To specify a secure LDAP server, use <i>ldaps://</i> in the
<tt>AuthLDAPURL</tt> directive, instead of <i>ldap://</i>.</p>
<h2><a id="frontpage" name="frontpage">Using Microsoft
FrontPage with mod_auth_ldap</a></h2>
authentication. Unfortunately, it is not possible to just
change to LDAP authentication by adding the proper directives,
because it will break the <em><b>Permissions</b></em> forms in
the FrontPage client, which attempt to modify the standard
text-based authorization files.</p>
<p>Once a FrontPage web has been created, adding LDAP
authentication to it is a matter of adding the following
directives to <em><b>every</b></em> <tt>.htaccess</tt> file
that gets created in the web</p>
<pre>
AuthLDAPURL the url
AuthLDAPAuthoritative off
AuthLDAPFrontPageHack on
</pre>
<p><tt>AuthLDAPAuthoritative</tt> must be off to allow
mod_auth_ldap to decline group authentication so that Apache
will fall back to file authentication for checking group
membership. This allows the FrontPage-managed group file to be
used.</p>
<h3><a id="howitworks" name="howitworks">How It Works</a></h3>
<p>FrontPage restricts access to a web by adding the
<tt>require valid-user</tt> directive to the <tt>.htaccess</tt>
files. If <tt>AuthLDAPFrontPageHack</tt> is not on, the
<tt>require valid-user</tt> directive will succeed for any user
who is valid <em><b>as far as LDAP is concerned</b></em>. This
means that anybody who has an entry in the LDAP directory is
considered a valid user, whereas FrontPage considers only those
people in the local user file to be valid. The purpose of the
hack is to force Apache to consult the local user file (which
is managed by FrontPage) - instead of LDAP - when handling the
<tt>require valid-user</tt> directive.</p>
<p>Once directives have been added as specified above,
FrontPage users will be able to perform all management
operations from the FrontPage client.</p>
<h3><a id="fpcaveats" name="fpcaveats">Caveats</a></h3>
<ul>
<li>When choosing the LDAP URL, the attribute to use for
authentication should be something that will also be valid
for putting into a <i>mod_auth</i> user file. The user ID is
ideal for this.</li>
<li>When adding users via FrontPage, FrontPage administrators
should choose usernames that already exist in the LDAP
directory (for obvious reasons). Also, the password that the
administrator enters into the form is ignored, since Apache
will actually be authenticating against the password in the
LDAP database, and not against the password in the local user
file. This could cause confusion for web administrators.</li>
<li>Apache must be compiled with <i>mod_auth</i> in order to
use FrontPage support. This is because Apache will still use
the <i>mod_auth</i> group file for determine the extent of a
user's access to the FrontPage web.</li>
<li>The directives must be put in the <tt>.htaccess</tt>
files. Attempting to put them inside
<tt><Location></tt> or <tt><Directory></tt>
directives won't work. This is because mod_auth_ldap has to
be able to grab the <tt>AuthUserFile</tt> directive that is
found in FrontPage <tt>.htaccess</tt> files so that it knows
where to look for the valid user list. If the mod_auth_ldap
directives aren't in the same <tt>.htaccess</tt> file as the
FrontPage directives, then the hack won't work, because
mod_auth_ldap will never get a chance to process the
<tt>.htaccess</tt> file, and won't be able to find the
FrontPage-managed user file.</li>
</ul>
<hr />
<h2><a id="AuthLDAPAuthoritative"
name="AuthLDAPAuthoritative">AuthLDAPAuthoritative
directive</a></h2>
rel="Help"><strong>Syntax:</strong></a> AuthLDAPAuthoritative
on|off<br />
<a href="directive-dict.html#Default"
rel="Help"><strong>Default:</strong></a>
<code>AuthLDAPAuthoritative 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> Extension<br />
<a href="directive-dict.html#Module"
rel="Help"><strong>Module:</strong></a> mod_auth_ldap</p>
<p>Set to <i>off</i> if this module should let other
authentication modules attempt to authenticate the user, should
authentication with this module fail. Control is only passed on
to lower modules if there is no DN or rule that matches the
supplied user name (as passed by the client).</p>
<hr />
<h2><a id="AuthLDAPBindDN" name="AuthLDAPBindDN">AuthLDAPBindDN
directive</a></h2>
rel="Help"><strong>Syntax:</strong></a> AuthLDAPBindDN
<em>distinguished-name</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> Extension<br />
<a href="directive-dict.html#Module"
rel="Help"><strong>Module:</strong></a> mod_auth_ldap</p>
<p>An optional DN used to bind to the server when searching for
entries. If not provided, mod_auth_ldap will use an anonymous
bind.</p>
<hr />
<h2><a id="AuthLDAPBindPassword"
name="AuthLDAPBindPassword">AuthLDAPBindPassword
directive</a></h2>
rel="Help"><strong>Syntax:</strong></a> AuthLDAPBindPassword
<em>password</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> Extension<br />
<a href="directive-dict.html#Module"
rel="Help"><strong>Module:</strong></a> mod_auth_ldap</p>
<p>A bind password to use in conjunction with the bind DN. Note
that the bind password is probably sensitive data, and should
be properly protected. You should only use the <a
href="#AuthLDAPBindDN"><tt>AuthLDAPBindDN</tt></a> and <a
href="#AuthLDAPBindPassword"><tt>AuthLDAPBindPassword</tt></a>
if you absolutely need them to search the directory.</p>
<hr />
<h2><a id="AuthLDAPCompareDNOnServer"
name="AuthLDAPCompareDNOnServer">AuthLDAPCompareDNOnServer
directive</a></h2>
rel="Help"><strong>Syntax:</strong></a>
AuthLDAPCompareDNOnServer on|off<br />
<a href="directive-dict.html#Default"
rel="Help"><strong>Default:</strong></a>
<code>AuthLDAPCompareDNOnServer 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> Extension<br />
<a href="directive-dict.html#Module"
rel="Help"><strong>Module:</strong></a> mod_auth_ldap</p>
<p>When set, mod_auth_ldap will use the LDAP server to compare
the DNs. This is the only foolproof way to compare DNs.
mod_auth_ldap will search the directory for the DN specified
with the <a href="#reqdn"><tt>require dn</tt></a> directive,
then, retrieve the DN and compare it with the DN retrieved from
the user entry. If this directive is not set, mod_auth_ldap
simply does a string comparison. It is possible to get false
negatives with this approach, but it is much faster. Note the
mod_ldap cache can speed up DN comparison in most
situations.</p>
<hr />
<h2><a id="AuthLDAPDereferenceAliases"
name="AuthLDAPDereferenceAliases">AuthLDAPDereferenceAliases
directive</a></h2>
rel="Help"><strong>Syntax:</strong></a>
AuthLDAPDereferenceAliases never|searching|finding|always<br />
<a href="directive-dict.html#Default"
rel="Help"><strong>Default:</strong></a>
<code>AuthLDAPDereferenceAliases Always</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> Extension<br />
<a href="directive-dict.html#Module"
rel="Help"><strong>Module:</strong></a> mod_auth_ldap</p>
<p>This directive specifies when mod_auth_ldap will
de-reference aliases during LDAP operations. The default is
<i>always</i>.</p>
<hr />
<h2><a id="AuthLDAPEnabled"
name="AuthLDAPEnabled">AuthLDAPEnabled directive</a></h2>
rel="Help"><strong>Syntax:</strong></a> AuthLDAPEnabled
on|off<br />
<a href="directive-dict.html#Default"
rel="Help"><strong>Default:</strong></a> <code>AuthLDAPEnabled
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> Extension<br />
<a href="directive-dict.html#Module"
rel="Help"><strong>Module:</strong></a> mod_auth_ldap</p>
<p>Set to <i>off</i> to disable mod_auth_ldap in certain
directories. This is useful if you have mod_auth_ldap enabled
at or near the top of your tree, but want to disable it
completely in certain locations.</p>
<hr />
<h2><a id="AuthLDAPFrontPageHack"
name="AuthLDAPFrontPageHack">AuthLDAPFrontPageHack
directive</a></h2>
rel="Help"><strong>Syntax:</strong></a> AuthLDAPFrontPageHack
on|off<br />
<a href="directive-dict.html#Default"
rel="Help"><strong>Default:</strong></a>
<code>AuthLDAPFronPageHack off</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> Extension<br />
<a href="directive-dict.html#Module"
rel="Help"><strong>Module:</strong></a> mod_auth_ldap</p>
<p>See the section on <a href="#frontpage">using Microsoft
FrontPage</a> with mod_auth_ldap.</p>
<hr />
<h2><a id="AuthLDAPGroupAttribute"
name="AuthLDAPGroupAttribute">AuthLDAPGroupAttribute
directive</a></h2>
rel="Help"><strong>Syntax:</strong></a> AuthLDAPGroupAttribute
<em>attribute</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> Extension<br />
<a href="directive-dict.html#Module"
rel="Help"><strong>Module:</strong></a> mod_auth_ldap</p>
<p>This directive specifies which LDAP attributes are used to
check for group membership. Multiple attributes can be used by
specifying this directive multiple times. If not specified,
then mod_auth_ldap uses the <tt>member</tt> and
<tt>uniquemember</tt> attributes.</p>
<hr />
<h2><a id="AuthLDAPGroupAttributeIsDN"
name="AuthLDAPGroupAttributeIsDN">AuthLDAPGroupAttributeIsDN
directive</a></h2>
rel="Help"><strong>Syntax:</strong></a>
AuthLDAPGroupAttributeIsDN on|off<br />
<a href="directive-dict.html#Default"
rel="Help"><strong>Default:</strong></a>
<code>AuthLDAPGroupAttributeIsDN 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> Extension<br />
<a href="directive-dict.html#Module"
rel="Help"><strong>Module:</strong></a> mod_auth_ldap</p>
<p>When set, this directive says to use the distinguished name
of the client username when checking for group membership.
Otherwise, the username will be used. For example, assume that
the client sent the username <i>bjenson</i>, which corresponds
to the LDAP DN <i>cn=Babs Jenson, o=Airius</i>. If this
directive is set, mod_auth_ldap will check if the group has
<i>cn=Babs Jenson, o=Airius</i> as a member. If this directive
is not set, then mod_auth_ldap will check if the group has
<i>bjenson</i> as a member.</p>
<hr />
<h2><a id="AuthLDAPRemoteUserIsDN"
name="AuthLDAPRemoteUserIsDN">AuthLDAPRemoteUserIsDN
directive</a></h2>
rel="Help"><strong>Syntax:</strong></a> AuthLDAPRemoteUserIsDN
on|off<br />
<a href="directive-dict.html#Default"
rel="Help"><strong>Default:</strong></a> <code>AuthLDAPUserIsDN
off</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> Extension<br />
<a href="directive-dict.html#Module"
rel="Help"><strong>Module:</strong></a> mod_auth_ldap</p>
<p>If this directive is set to on, the value of the
<i>REMOTE_USER</i> environment variable will be set to the full
distinguished name of the authenticated user, rather than just
the username that was passed by the client. It is turned off by
default.</p>
<hr />
<h2><a id="AuthLDAPStartTLS"
name="AuthLDAPStartTLS">AuthLDAPStartTLS directive</a></h2>
rel="Help"><strong>Syntax:</strong></a> AuthLDAPStartTLS
on|off<br />
<a href="directive-dict.html#Default"
rel="Help"><strong>Default:</strong></a> <code>AuthLDAPStartTLS
off</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> Extension<br />
<a href="directive-dict.html#Module"
rel="Help"><strong>Module:</strong></a> mod_auth_ldap</p>
<p>If this directive is set to on, mod_auth_ldap will start a
secure TLS session after connecting to the LDAP server. This
requires your LDAP server to support TLS.</p>
<hr />
<h2><a id="AuthLDAPUrl" name="AuthLDAPUrl">AuthLDAPUrl
directive</a></h2>
rel="Help"><strong>Syntax:</strong></a> AuthLDAPUrl
<em>url</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> Extension<br />
<a href="directive-dict.html#Module"
rel="Help"><strong>Module:</strong></a> mod_auth_ldap</p>
<p>An RFC 2255 URL which specifies the LDAP search parameters
to use. The syntax of the URL is</p>
<pre>
</pre>
<table border="0" bgcolor="#ffffff">
<tr valign="top">
<td colspan="1" align="left">ldap</td>
<td colspan="1" align="left">For regular ldap, use the
string <i>ldap</i>. For secure LDAP, use <i>ldaps</i>
instead. Secure LDAP is only available if Apache was linked
to an LDAP library with SSL support.</td>
</tr>
<tr valign="top">
<td colspan="1" align="left">host:port</td>
<td colspan="1" align="left">
<i>localhost:389</i> for <i>ldap</i>, and
<i>localhost:636</i> for <i>ldaps</i>). To specify
multiple, redundant LDAP servers, just list all servers,
separated by spaces. mod_auth_ldap will try connecting to
each server in turn, until it makes a successful
connection.</p>
<p>Once a connection has been made to a server, that
connection remains active for the life of the
<i>httpd</i> process, or until the LDAP server goes
down.</p>
<p>If the LDAP server goes down and breaks an existing
connection, mod_auth_ldap will attempt to re-connect,
starting with the primary server, and trying each
redundant server in turn. Note that this is different
than a true round-robin search.</p>
</td>
</tr>
<tr valign="top">
<td colspan="1" align="left">basedn</td>
<td colspan="1" align="left">The DN of the branch of the
directory where all searches should start from. At the very
least, this must be the top of your directory tree, but
could also specify a subtree in the directory.</td>
</tr>
<tr valign="top">
<td colspan="1" align="left">attribute</td>
<td colspan="1" align="left">The attribute to search for.
Although RFC 2255 allows a comma-separated list of
attributes, only the first attribute will be used, no
matter how many are provided. If no attributes are
provided, the default is to use <tt>uid</tt>. It's a good
idea to choose an attribute that will be unique across all
entries in the subtree you will be using.</td>
</tr>
<tr valign="top">
<td colspan="1" align="left">scope</td>
<td colspan="1" align="left">The scope of the search. Can
be either <i>one</i> or <i>sub</i>. Note that a scope of
<i>base</i> is also supported by RFC 2255, but is not
supported by this module. If the scope is not provided, or
if <i>base</i> scope is specified, the default is to use a
scope of <i>sub</i>.</td>
</tr>
<tr valign="top">
<td colspan="1" align="left">filter</td>
<td colspan="1" align="left">A valid LDAP search filter. If
not provided, defaults to <tt>(objectClass=*)</tt>, which
will search for all objects in the tree. Filters are
limited to approximately 8000 characters (the definition of
<i>MAX_STRING_LEN</i> in the Apache source code). This
should be than sufficient for any application.</td>
</tr>
</table>
<p>When doing searches, the attribute, filter and username
passed by the HTTP client are combined to create a search
filter that looks like
<tt>(&(<i>filter</i>)(<i>attribute</i>=<i>username</i>))</tt>.</p>
<p>For example, consider an URL of
a client attempts to connect using a username of <i>Babs
Jenson</i>, the resulting search filter will be
<tt>(&(posixid=*)(cn=Babs Jenson))</tt>.</p>
<p>See above for examples of <a
href="#AuthLDAPURL"><tt>AuthLDAPURL</tt></a> URLs.</p>
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