home *** CD-ROM | disk | FTP | other *** search
<?xml version="1.0" encoding="ISO-8859-1"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head><!-- XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX This file is generated from xml source: DO NOT EDIT XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX --> <title>mod_ldap - Apache HTTP Server</title> <link href="../style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" /> <link href="../style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" /> <link href="../style/css/manual-print.css" rel="stylesheet" media="print" type="text/css" /> <link href="../images/favicon.ico" rel="shortcut icon" /></head> <body> <div id="page-header"> <p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/directives.html">Directives</a> | <a href="../faq/">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p> <p class="apache">Apache HTTP Server Version 2.0</p> <img alt="" src="../images/feather.gif" /></div> <div class="up"><a href="./"><img title="<-" alt="<-" src="../images/left.gif" /></a></div> <div id="path"> <a href="http://www.apache.org/">Apache</a> > <a href="http://httpd.apache.org/">HTTP Server</a> > <a href="http://httpd.apache.org/docs-project/">Documentation</a> > <a href="../">Version 2.0</a> > <a href="./">Modules</a></div> <div id="page-content"> <div id="preamble"><h1>Apache Module mod_ldap</h1> <div class="toplang"> <p><span>Available Languages: </span><a href="../en/mod/mod_ldap.html" title="English"> en </a></p> </div> <table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>LDAP connection pooling and result caching services for use by other LDAP modules</td></tr> <tr><th><a href="module-dict.html#Status">Status:</a></th><td>Experimental</td></tr> <tr><th><a href="module-dict.html#ModuleIdentifier">ModuleáIdentifier:</a></th><td>ldap_module</td></tr> <tr><th><a href="module-dict.html#SourceFile">SourceáFile:</a></th><td>util_ldap.c</td></tr> <tr><th><a href="module-dict.html#Compatibility">Compatibility:</a></th><td>Available in version 2.0.41 and later</td></tr></table> <h3>Summary</h3> <p>This module was created to improve the performance of websites relying on backend connections to LDAP servers. In addition to the functions provided by the standard LDAP libraries, this module adds an LDAP connection pool and an LDAP shared memory cache.</p> <p>To enable this module, LDAP support must be compiled into apr-util. This is achieved by adding the <code>--with-ldap</code> flag to the <code>./configure</code> script when building Apache.</p> <p>SSL support requires that <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> be linked with one of the following LDAP SDKs: <a href="http://www.openldap.org/"> OpenLDAP SDK</a> (both 1.x and 2.x), <a href="http://developer.novell.com/ndk/cldap.htm"> Novell LDAP SDK</a> or the <a href="http://www.iplanet.com/downloads/developer/"> iPlanet(Netscape)</a> SDK.</p> </div> <div id="quickview"><h3 class="directives">Directives</h3> <ul id="toc"> <li><img alt="" src="../images/down.gif" /> <a href="#ldapcacheentries">LDAPCacheEntries</a></li> <li><img alt="" src="../images/down.gif" /> <a href="#ldapcachettl">LDAPCacheTTL</a></li> <li><img alt="" src="../images/down.gif" /> <a href="#ldapopcacheentries">LDAPOpCacheEntries</a></li> <li><img alt="" src="../images/down.gif" /> <a href="#ldapopcachettl">LDAPOpCacheTTL</a></li> <li><img alt="" src="../images/down.gif" /> <a href="#ldapsharedcachefile">LDAPSharedCacheFile</a></li> <li><img alt="" src="../images/down.gif" /> <a href="#ldapsharedcachesize">LDAPSharedCacheSize</a></li> <li><img alt="" src="../images/down.gif" /> <a href="#ldaptrustedca">LDAPTrustedCA</a></li> <li><img alt="" src="../images/down.gif" /> <a href="#ldaptrustedcatype">LDAPTrustedCAType</a></li> </ul> <h3>Topics</h3> <ul id="topics"> <li><img alt="" src="../images/down.gif" /> <a href="#exampleconfig">Example Configuration</a></li> <li><img alt="" src="../images/down.gif" /> <a href="#pool">LDAP Connection Pool</a></li> <li><img alt="" src="../images/down.gif" /> <a href="#cache">LDAP Cache</a></li> <li><img alt="" src="../images/down.gif" /> <a href="#usingssltls">Using SSL</a></li> </ul></div> <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> <div class="section"> <h2><a name="exampleconfig" id="exampleconfig">Example Configuration</a></h2> <p>The following is an example configuration that uses <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> to increase the performance of HTTP Basic authentication provided by <code class="module"><a href="../mod/mod_auth_ldap.html">mod_auth_ldap</a></code>.</p> <div class="example"><p><code> # Enable the LDAP connection pool and shared<br /> # memory cache. Enable the LDAP cache status<br /> # handler. Requires that mod_ldap and mod_auth_ldap<br /> # be loaded. Change the "yourdomain.example.com" to<br /> # match your domain.<br /> <br /> LDAPSharedCacheSize 200000<br /> LDAPCacheEntries 1024<br /> LDAPCacheTTL 600<br /> LDAPOpCacheEntries 1024<br /> LDAPOpCacheTTL 600<br /> <br /> <Location /ldap-status><br /> <span class="indent"> SetHandler ldap-status<br /> Order deny,allow<br /> Deny from all<br /> Allow from yourdomain.example.com<br /> AuthLDAPEnabled on<br /> AuthLDAPURL ldap://127.0.0.1/dc=example,dc=com?uid?one<br /> AuthLDAPAuthoritative on<br /> require valid-user<br /> </span> </Location> </code></p></div> </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> <div class="section"> <h2><a name="pool" id="pool">LDAP Connection Pool</a></h2> <p>LDAP connections are pooled from request to request. This allows the LDAP server to remain connected and bound ready for the next request, without the need to unbind/connect/rebind. The performance advantages are similar to the effect of HTTP keepalives.</p> <p>On a busy server it is possible that many requests will try and access the same LDAP server connection simultaneously. Where an LDAP connection is in use, Apache will create a new connection alongside the original one. This ensures that the connection pool does not become a bottleneck.</p> <p>There is no need to manually enable connection pooling in the Apache configuration. Any module using this module for access to LDAP services will share the connection pool.</p> </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> <div class="section"> <h2><a name="cache" id="cache">LDAP Cache</a></h2> <p>For improved performance, <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> uses an aggressive caching strategy to minimize the number of times that the LDAP server must be contacted. Caching can easily double or triple the throughput of Apache when it is serving pages protected with mod_auth_ldap. In addition, the load on the LDAP server will be significantly decreased.</p> <p><code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> supports two types of LDAP caching during the search/bind phase with a <em>search/bind cache</em> and during the compare phase with two <em>operation caches</em>. Each LDAP URL that is used by the server has its own set of these three caches.</p> <h3><a name="search-bind" id="search-bind">The Search/Bind Cache</a></h3> <p>The process of doing a search and then a bind is the most time-consuming aspect of LDAP operation, especially if the directory is large. The search/bind cache is used to cache all searches that resulted in successful binds. Negative results (<em>i.e.</em>, unsuccessful searches, or searches that did not result in a successful bind) are not cached. The rationale behind this decision is that connections with invalid credentials are only a tiny percentage of the total number of connections, so by not caching invalid credentials, the size of the cache is reduced.</p> <p><code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> stores the username, the DN retrieved, the password used to bind, and the time of the bind in the cache. Whenever a new connection is initiated with the same username, <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> compares the password of the new connection with the password in the cache. If the passwords match, and if the cached entry is not too old, <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> bypasses the search/bind phase.</p> <p>The search and bind cache is controlled with the <code class="directive"><a href="#ldapcacheentries">LDAPCacheEntries</a></code> and <code class="directive"><a href="#ldapcachettl">LDAPCacheTTL</a></code> directives.</p> <h3><a name="opcaches" id="opcaches">Operation Caches</a></h3> <p>During attribute and distinguished name comparison functions, <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> uses two operation caches to cache the compare operations. The first compare cache is used to cache the results of compares done to test for LDAP group membership. The second compare cache is used to cache the results of comparisons done between distinguished names.</p> <p>The behavior of both of these caches is controlled with the <code class="directive"><a href="#ldapopcacheentries">LDAPOpCacheEntries</a></code> and <code class="directive"><a href="#ldapopcachettl">LDAPOpCacheTTL</a></code> directives.</p> <h3><a name="monitoring" id="monitoring">Monitoring the Cache</a></h3> <p><code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> has a content handler that allows administrators to monitor the cache performance. The name of the content handler is <code>ldap-status</code>, so the following directives could be used to access the <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> cache information:</p> <div class="example"><p><code> <Location /server/cache-info><br /> <span class="indent"> SetHandler ldap-status<br /> </span> </Location> </code></p></div> <p>By fetching the URL <code>http://servername/cache-info</code>, the administrator can get a status report of every cache that is used by <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> cache. Note that if Apache does not support shared memory, then each <code>httpd</code> instance has its own cache, so reloading the URL will result in different information each time, depending on which <code>httpd</code> instance processes the request.</p> </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> <div class="section"> <h2><a name="usingssltls" id="usingssltls">Using SSL</a></h2> <p>The ability to create an SSL connections to an LDAP server is defined by the directives <code class="directive"><a href="#
ldaptrustedca"> LDAPTrustedCA</a></code> and <code class="directive"><a href="#
ldaptrustedcatype"> LDAPTrustedCAType</a></code>. These directives specify the certificate file or database and the certificate type. Whenever the LDAP url includes <em>ldaps://</em>, <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> will establish a secure connection to the LDAP server.</p> <div class="example"><p><code> # Establish an SSL LDAP connection. Requires that <br /> # mod_ldap and mod_auth_ldap be loaded. Change the <br /> # "yourdomain.example.com" to match your domain.<br /> <br /> LDAPTrustedCA /certs/certfile.der<br /> LDAPTrustedCAType DER_FILE<br /> <br /> <Location /ldap-status><br /> <span class="indent"> SetHandler ldap-status<br /> Order deny,allow<br /> Deny from all<br /> Allow from yourdomain.example.com<br /> AuthLDAPEnabled on<br /> AuthLDAPURL ldaps://127.0.0.1/dc=example,dc=com?uid?one<br /> AuthLDAPAuthoritative on<br /> require valid-user<br /> </span> </Location> </code></p></div> <p>If <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> is linked against the Netscape/iPlanet LDAP 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 <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> needs to be told where it can find a database containing the known CAs. This database is in the same format as Netscape Communicator's <code>cert7.db</code> database. The easiest way to get this file is to start up a fresh copy of Netscape, and grab the resulting <code>$HOME/.netscape/cert7.db</code> file.</p> </div> <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> <div class="directive-section"><h2><a name="LDAPCacheEntries" id="LDAPCacheEntries">LDAPCacheEntries</a> <a name="ldapcacheentries" id="ldapcacheentries">Directive</a></h2> <table class="directive"> <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Maximum number of entries in the primary LDAP cache</td></tr> <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LDAPCacheEntries <var>number</var></code></td></tr> <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LDAPCacheEntries 1024</code></td></tr> <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr> <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ldap</td></tr> </table> <p>Specifies the maximum size of the primary LDAP cache. This cache contains successful search/binds. Set it to 0 to turn off search/bind caching. The default size is 1024 cached searches.</p> </div> <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> <div class="directive-section"><h2><a name="LDAPCacheTTL" id="LDAPCacheTTL">LDAPCacheTTL</a> <a name="ldapcachettl" id="ldapcachettl">Directive</a></h2> <table class="directive"> <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Time that cached items remain valid</td></tr> <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LDAPCacheTTL <var>seconds</var></code></td></tr> <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LDAPCacheTTL 600</code></td></tr> <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr> <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ldap</td></tr> </table> <p>Specifies the time (in seconds) that an item in the search/bind cache remains valid. The default is 600 seconds (10 minutes).</p> </div> <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> <div class="directive-section"><h2><a name="LDAPOpCacheEntries" id="LDAPOpCacheEntries">LDAPOpCacheEntries</a> <a name="ldapopcacheentries" id="ldapopcacheentries">Directive</a></h2> <table class="directive"> <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Number of entries used to cache LDAP compare operations</td></tr> <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LDAPOpCacheEntries <var>number</var></code></td></tr> <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LDAPOpCacheEntries 1024</code></td></tr> <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr> <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ldap</td></tr> </table> <p>This specifies the number of entries <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> will use to cache LDAP compare operations. The default is 1024 entries. Setting it to 0 disables operation caching.</p> </div> <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> <div class="directive-section"><h2><a name="LDAPOpCacheTTL" id="LDAPOpCacheTTL">LDAPOpCacheTTL</a> <a name="ldapopcachettl" id="ldapopcachettl">Directive</a></h2> <table class="directive"> <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Time that entries in the operation cache remain valid</td></tr> <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LDAPOpCacheTTL <var>seconds</var></code></td></tr> <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LDAPOpCacheTTL 600</code></td></tr> <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr> <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ldap</td></tr> </table> <p>Specifies the time (in seconds) that entries in the operation cache remain valid. The default is 600 seconds.</p> </div> <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> <div class="directive-section"><h2><a name="LDAPSharedCacheFile" id="LDAPSharedCacheFile">LDAPSharedCacheFile</a> <a name="ldapsharedcachefile" id="ldapsharedcachefile">Directive</a></h2> <table class="directive"> <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Sets the shared memory cache file</td></tr> <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LDAPSharedCacheFile <var>directory-path/filename</var></code></td></tr> <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr> <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ldap</td></tr> </table> <p>Specifies the directory path and file name of the shared memory cache file. If not set, anonymous shared memory will be used if the platform supports it.</p> </div> <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> <div class="directive-section"><h2><a name="LDAPSharedCacheSize" id="LDAPSharedCacheSize">LDAPSharedCacheSize</a> <a name="ldapsharedcachesize" id="ldapsharedcachesize">Directive</a></h2> <table class="directive"> <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Size in bytes of the shared-memory cache</td></tr> <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LDAPSharedCacheSize <var>bytes</var></code></td></tr> <tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>LDAPSharedCacheSize 102400</code></td></tr> <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr> <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ldap</td></tr> </table> <p>Specifies the number of bytes to allocate for the shared memory cache. The default is 100kb. If set to 0, shared memory caching will not be used.</p> </div> <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> <div class="directive-section"><h2><a name="LDAPTrustedCA" id="LDAPTrustedCA">LDAPTrustedCA</a> <a name="ldaptrustedca" id="ldaptrustedca">Directive</a></h2> <table class="directive"> <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Sets the file containing the trusted Certificate Authority certificate or database</td></tr> <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LDAPTrustedCA <var>directory-path/filename</var></code></td></tr> <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr> <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ldap</td></tr> </table> <p>It specifies the directory path and file name of the trusted CA <code class="module"><a href="../mod/mod_ldap.html">mod_ldap</a></code> should use when establishing an SSL connection to an LDAP server. If using the Netscape/iPlanet Directory SDK, the file name should be <code>cert7.db</code>.</p> </div> <div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> <div class="directive-section"><h2><a name="LDAPTrustedCAType" id="LDAPTrustedCAType">LDAPTrustedCAType</a> <a name="ldaptrustedcatype" id="ldaptrustedcatype">Directive</a></h2> <table class="directive"> <tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Specifies the type of the Certificate Authority file</td></tr> <tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>LDAPTrustedCAType <var>type</var></code></td></tr> <tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr> <tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Experimental</td></tr> <tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ldap</td></tr> </table> <p>The following types are supported:<br /> DER_FILE - file in binary DER format<br /> BASE64_FILE - file in Base64 format<br /> CERT7_DB_PATH - Netscape certificate database file ")</p> </div> </div> <div class="bottomlang"> <p><span>Available Languages: </span><a href="../en/mod/mod_ldap.html" title="English"> en </a></p> </div><div id="footer"> <p class="apache">Copyright 1999-2004 The Apache Software Foundation.<br />Licensed under the <a href="http://www.apache.org/licenses/LICENSE-2.0">Apache License, Version 2.0</a>.</p> <p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/directives.html">Directives</a> | <a href="../faq/">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p></div> </body></html> 
