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Posted to cvs@httpd.apache.org by sl...@apache.org on 2002/08/24 20:26:20 UTC
cvs commit: httpd-2.0/docs/manual sections.xml sections.html.en
slive 2002/08/24 11:26:20
Modified: docs/manual sections.html.en
Added: docs/manual sections.xml
Log:
Convert to xml and do a MAJOR revision and expansion of the
sections (<directory>, <location>, etc) docs.
Further review by config-merging experts would be appreciated.
Reviewed by: Rich Bowen, Andre Malo
Revision Changes Path
1.15 +376 -128 httpd-2.0/docs/manual/sections.html.en
Index: sections.html.en
===================================================================
RCS file: /home/cvs/httpd-2.0/docs/manual/sections.html.en,v
retrieving revision 1.14
retrieving revision 1.15
diff -u -d -b -u -r1.14 -r1.15
--- sections.html.en 25 Jul 2002 21:46:38 -0000 1.14
+++ sections.html.en 24 Aug 2002 18:26:19 -0000 1.15
@@ -1,151 +1,399 @@
-<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
- "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
+<html><head><META http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><!--
+ XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
+ This file is generated from xml source: DO NOT EDIT
+ XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
+ --><title>Configuration Sections - Apache HTTP Server</title><link href="./style/manual.css" type="text/css" rel="stylesheet"></head><body><blockquote><div align="center"><img src="./images/sub.gif" alt="[APACHE DOCUMENTATION]"><h3>Apache HTTP Server Version 2.0</h3></div><h1 align="center">Configuration Sections</h1> <p>Directives in the <a href="configuring.html">configuration files</a> may apply to the
+entire server, or they may be restricted to apply only to particular
+directories, files, hosts, or URLs. This document describes how to
+use configuration section containers or <code>.htaccess</code> files
+to change the scope of other configuration directives.</p>
+<ul><li><a href="#types">Types of Configuration Section Containers</a></li><li><a href="#file-and-web">Filesystem and Webspace</a><ul><li><a href="#filesystem">Filesystem Containers</a></li><li><a href="#webspace">Webspace Containers</a></li><li><a href="#wildcards">Wildcards and Regular Expressions</a></li><li><a href="#whichwhen">What to use When</a></li></ul></li><li><a href="#virtualhost">Virtual Hosts</a></li><li><a href="#proxy">Proxy</a></li><li><a href="#whatwhere">What Directives are Allowed?</a></li><li><a href="#mergin">How the sections are merged</a><ul><li><a href="#merge-examples">Some Examples</a></li></ul></li></ul><hr><h2><a name="types">Types of Configuration Section Containers</a></h2>
-<html xmlns="http://www.w3.org/1999/xhtml">
- <head>
- <meta name="generator" content="HTML Tidy, see www.w3.org" />
+<table border="1"><tr><td valign="top"><strong>Related Modules</strong><br><br><code><a href="./mod/core.html">core</a></code><br><code><a href="./mod/mod_proxy.html">mod_proxy</a></code><br></td><td valign="top"><strong>Related Directives</strong><br><br><a href="./mod/core.html#directory" class="directive"><code class="directive"><Directory></code></a><br><a href="./mod/core.html#directorymatch" class="directive"><code class="directive"><DirectoryMatch></code></a><br><a href="./mod/core.html#files" class="directive"><code class="directive"><Files></code></a><br><a href="./mod/core.html#filesmatch" class="directive"><code class="directive"><FilesMatch></code></a><br><a href="./mod/core.html#ifdefine" class="directive"><code class="directive"><IfDefine></code></a><br><a href="./mod/core.html#ifmodule" class="directive"><code class="directive"><IfModule></code></a><br><a href="./mod/core.html#location" class="directive"><code class="directive"><Location></code></a><br><a href="./mod/core.html#locationmatch" class="directive"><code class="directive"><LocationMatch></code></a><br><a href="./mod/proxy.html#proxy" class="directive"><code class="directive"><Proxy></code></a><br><a href="./mod/core.html#virtualhost" class="directive"><code class="directive"><VirtualHost></code></a><br></td></tr></table>
- <title>How Directory, Location and Files sections work</title>
- </head>
- <!-- Background white, links blue (unvisited), navy (visited), red (active) -->
+<p>There are two basic types of containers. Most containers are
+evaluated for each request. The enclosed directives are applied only
+for those requests that match the containers. The <a href="./mod/core.html#ifdefine" class="directive"><code class="directive"><IfDefine></code></a> and <a href="./mod/core.html#ifmodule" class="directive"><code class="directive"><IfModule></code></a> containers, on the
+other hand, are evaluated only at server startup and restart. If
+their conditions are true at startup, then the enclosed directives
+will apply to all requests. If the conditions are not true, the
+enclosed directives will be ignored.</p>
- <body bgcolor="#FFFFFF" text="#000000" link="#0000FF"
- vlink="#000080" alink="#FF0000">
- <!--#include virtual="header.html" -->
+<p>The <a href="./mod/core.html#ifdefine" class="directive"><code class="directive"><IfDefine></code></a> directive
+encloses directives that will only be applied if an appropriate
+parameter is defined on the <code>httpd</code> command line. For example,
+with the following configuration, all requests will be redirected
+to another site only if the server is started using
+<code>httpd -DClosedForNow</code>:</p>
- <h1 align="center">How Directory, Location and Files sections
- work</h1>
+<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
+<IfDefine ClosedForNow><br>
+Redirect / http://otherserver.example.com/<br>
+</IfDefine>
+</code></td></tr></table></blockquote>
- <p>The sections <a
- href="mod/core.html#directory"><code><Directory></code></a>,
- <a
- href="mod/core.html#location"><code><Location></code></a>
- and <a
- href="mod/core.html#files"><code><Files></code></a> can
- contain directives which only apply to specified directories,
- URLs or files respectively. Also htaccess files can be used
- inside a directory to apply directives to that directory. This
- document explains how these different sections differ and how
- they relate to each other when Apache decides which directives
- apply for a particular directory or request URL.</p>
+<p>The <a href="./mod/core.html#ifmodule" class="directive"><code class="directive"><IfModule></code></a>
+directive is very similar, except it encloses directives that will
+only be applied if a particular module is available in the server.
+The module must either be statically compiled in the server, or it
+must be dynamically compiled and its <a href="./mod/mod_so.html#loadmodule" class="directive"><code class="directive">LoadModule</code></a> line must be earlier in the
+configuration file. This directive should only be used if you need
+your configuration file to work whether or not certain modules are
+installed. It should not be used to enclose directives that you want
+to work all the time, because it can suppress useful error messages
+about missing modules.</p>
- <h2>Directives allowed in the sections</h2>
+<p>In the following example, the <a href="./mod/mod_mime_magic.html#mimemagicfiles" class="directive"><code class="directive">MimeMagicFiles</code></a> directive will be
+applied only if <code><a href="./mod/mod_mime_magic.html">mod_mime_magic</a></code> is available.</p>
- <p>Everything that is syntactically allowed in
- <code><Directory></code> is also allowed in
- <code><Location></code> (except a
- sub-<code><Files></code> section). Semantically, however
- some things, most notably <code>AllowOverride</code> and the
- two options <code>FollowSymLinks</code> and
- <code>SymLinksIfOwnerMatch</code>, make no sense in
- <code><Location></code>,
- <code><LocationMatch></code> or
- <code><DirectoryMatch></code>. The same for
- <code><Files></code> -- syntactically everything is fine,
- but semantically some things are different.</p>
+<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
+<IfModule mod_mime_magic.c><br>
+MimeMagicFile conf/magic<br>
+</IfModule>
+</code></td></tr></table></blockquote>
- <h2>How the sections are merged</h2>
+<p>Both <a href="./mod/core.html#ifdefine" class="directive"><code class="directive"><IfDefine></code></a>
+and <a href="./mod/core.html#ifmodule" class="directive"><code class="directive"><IfModule></code></a>
+can apply negative conditions by preceding their test with "!".
+Also, these sections can be nested to achieve more complex
+restrictions.</p>
+<h2><a name="file-and-web">Filesystem and Webspace</a></h2>
- <p>The order of merging is:</p>
+<p>The most commonly used configuration section containers are the
+ones that change the configuration of particular places in the
+filesystem or webspace. First, it is important to understand the
+difference between the two. The filesystem is the view of your disks
+as seen by your operating system. For example, in a default install,
+Apache resides at <code>/usr/local/apache2</code> in the Unix
+filesystem or <code>"c:/Program Files/Apache Group/Apache2"</code> in
+the Windows filesystem. (Note that forward slashes should always be
+used as the path separator in Apache, even for Windows.) In contrast,
+the webspace is the view of your site as delivered by the web server
+and seen by the client. So the path <code>/dir/</code> in the
+webspace corresponds to the path
+<code>/usr/local/apache2/htdocs/dir/</code> in the filesystem of a
+default Apache install on Unix. The webspace need not map directly to
+the filesystem, since webpages may be generated dynamically
+from databases or other locations.</p>
- <ol>
- <li><code><Directory></code> (except regular
- expressions) and .htaccess done simultaneously (with
- .htaccess, if allowed, overriding
- <code><Directory></code>)</li>
+<h3><a name="filesystem">Filesystem Containers</a></h3>
- <li><code><DirectoryMatch></code>, and
- <code><Directory></code> with regular expressions</li>
+<p>The <a href="./mod/core.html#directory" class="directive"><code class="directive"><Directory></code></a>
+and <a href="./mod/core.html#files" class="directive"><code class="directive"><Files></code></a>
+directives, along with their regex counterparts, apply directives to
+parts of the filesystem. Directives enclosed in a <a href="./mod/core.html#directory" class="directive"><code class="directive"><Directory></code></a> section apply to
+the named filesystem directory and all subdirectories of that
+directory. The same effect can be obtained using <a href="howto/htaccess.html">.htaccess files</a>. For example, in the
+following configuration, directory indexes will be enabled for the
+<code>/var/web/dir1</code> directory and all subdirectories.</p>
- <li><code><Files></code> and
- <code><FilesMatch></code> done simultaneously</li>
+<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
+<Directory /var/web/dir1><br>
+Options +Indexes<br>
+</Directory>
+</code></td></tr></table></blockquote>
- <li><code><Location></code> and
- <code><LocationMatch></code> done simultaneously</li>
- </ol>
+<p>Directives enclosed in a <a href="./mod/core.html#files" class="directive"><code class="directive"><Files></code></a> section apply to any file with
+the specified name, regardless of what directory it lies in.
+So for example, the following configuration directives will,
+when placed in the main section of the configuration file,
+deny access to any file named <code>private.html</code> regardless
+of where it is found.</p>
- <p>Apart from <code><Directory></code>, each group is
- processed in the order that they appear in the configuration
- files. <code><Directory></code> (group 1 above) is
- processed in the order shortest directory component to longest.
- If multiple <code><Directory></code> sections apply to
- the same directory they are processed in the configuration
- file order. Configurations included
- via the <code>Include</code> directive will be treated as if
- they were inside the including file at the location of the
- <code>Include</code> directive.</p>
+<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
+<Files private.html><br>
+Order allow,deny<br>
+Deny from all<br>
+</Files>
+</code></td></tr></table></blockquote>
- <p>Sections inside <code><VirtualHost></code> sections
- are applied <em>after</em> the corresponding sections outside
- the virtual host definition. This allows virtual hosts to
- override the main server configuration.</p>
+<p>To address files found in a particular part of the filesystem, the
+<a href="./mod/core.html#files" class="directive"><code class="directive"><Files></code></a> and
+<a href="./mod/core.html#directory" class="directive"><code class="directive"><Directory></code></a> sections
+can be combined. For example, the following configuration will deny
+access to <code>/var/web/dir1/private.html</code>,
+<code>/var/web/dir1/subdir2/private.html</code>,
+<code>/var/web/dir1/subdir3/private.html</code>, and any other instance
+of <code>private.html</code> found under the <code>/var/web/dir1/</code>
+directory.</p>
- <p>Later sections override earlier ones.</p>
+<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
+<Directory /var/web/dir1><br>
+<Files private.html><br>
+Order allow,deny<br>
+Deny from all<br>
+</Files><br>
+</Directory>
+</code></td></tr></table></blockquote>
- <h2>Notes about using sections</h2>
- <p>The general guidelines are:</p>
+<h3><a name="webspace">Webspace Containers</a></h3>
- <ul>
- <li>If you are attempting to match objects at the filesystem
- level then you must use <code><Directory></code> and/or
- <code><Files></code>.</li>
+<p>The <a href="./mod/core.html#location" class="directive"><code class="directive"><Location></code></a>
+directive and its regex counterpart, on the other hand, change the
+configuration for content in the webspace. For example, the following
+configuration prevents access to any URL-path that begins in /private.
+In particular, it will apply to requests for
+<code>http://yoursite.example.com/private</code>,
+<code>http://yoursite.example.com/private123</code>, and
+<code>http://yoursite.example.com/private/dir/file.html</code> as well
+as any other requests starting with the <code>/private</code> string.</p>
- <li>If you are attempting to match objects at the URL level
- then you must use <code><Location></code></li>
- </ul>
+<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
+<Location /private><br>
+Order Allow,Deny<br>
+Deny from all<br>
+</Location>
+</code></td></tr></table></blockquote>
- <p>But a notable exception is:</p>
+<p>The <a href="./mod/core.html#location" class="directive"><code class="directive"><Location></code></a>
+directive need not have anything to do with the filesystem.
+For example, the following example shows how to map a particular
+URL to an internal Apache handler provided by <code><a href="./mod/mod_status.html">mod_status</a></code>.
+No file called <code>server-status</code> needs to exist in the
+filesystem.</p>
- <ul>
- <li>proxy control is done via <code><Directory></code>.
- This is a legacy mistake because the proxy existed prior to
- <code><Location></code>. A future version of the config
- language should probably switch this to
- <code><Location></code>.</li>
- </ul>
+<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
+<Location /server-status><br>
+SetHandler server-status<br>
+</Location>
+</code></td></tr></table></blockquote>
- <p>Note about .htaccess parsing:</p>
- <ul>
- <li>Modifying .htaccess parsing during Location doesn't do
- anything because .htaccess parsing has already occurred.</li>
- </ul>
+<h3><a name="wildcards">Wildcards and Regular Expressions</a></h3>
- <p><code><Location></code> and symbolic links:</p>
+<p>The <a href="./mod/core.html#directory" class="directive"><code class="directive"><Directory></code></a>,
+<a href="./mod/core.html#files" class="directive"><code class="directive"><Files></code></a>, and
+<a href="./mod/core.html#location" class="directive"><code class="directive"><Location></code></a>
+directives can each use the shell-style wildcard characters "?" to
+match any single character, "*" to match any set of characters, and
+character classes like [a-zA-Z] to match particular characters. This
+is useful to apply the same configuration to a group of filesystem or
+webspace locations. If even more flexible matching is required, each
+container has a regular-expression (regex) counterpart <a href="./mod/core.html#directorymatch" class="directive"><code class="directive"><DirectoryMatch></code></a>, <a href="./mod/core.html#filesmatch" class="directive"><code class="directive"><FilesMatch></code></a>, and <a href="./mod/core.html#locationmatch" class="directive"><code class="directive"><LocationMatch></code></a> that allow
+perl-compatible<a href="glossary.html#regex">regular expressions</a>
+to be used in choosing the matches. But see the section below on
+configuration merging to find out how using regex sections will change
+how directives are applied.</p>
- <ul>
- <li>It is not possible to use "<code>Options
- FollowSymLinks</code>" or "<code>Options
- SymLinksIfOwnerMatch</code>" inside a
- <code><Location></code>,
- <code><LocationMatch></code> or
- <code><DirectoryMatch></code> section (the options are
- simply ignored). Using the options in question is only
- possible inside a <code><Directory></code> section (or
- a <code>.htaccess</code> file).</li>
- </ul>
+<p>A non-regex wildcard section that changes the configuration of
+all user directories could look as follows:</p>
- <p><code><Files></code> and <code>Options</code>:</p>
+<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
+<Directory /home/*/public_html><br>
+Options Indexes<br>
+</Directory>
+</code></td></tr></table></blockquote>
- <ul>
- <li>Apache won't check for it, but using an
- <code>Options</code> directive inside a
- <code><Files></code> section has no effect.</li>
- </ul>
+<p>Using regex sections, we can deny access to many types of image files
+at once:</p>
+<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
+<FilesMatch \.(?i:gif|jpe?g|png)$><br>
+Order allow,deny<br>
+Deny from all<br>
+</FilesMatch>
+</code></td></tr></table></blockquote>
- <p>Another note:</p>
- <ul>
- <li>There is actually a
+
+<h3><a name="whichwhen">What to use When</a></h3>
+
+<p>Choosing between filesystem containers and webspace containers is
+actually quite easy. When applying directives to objects that reside
+in the filesystem always use <a href="./mod/core.html#directory" class="directive"><code class="directive"><Directory></code></a> or <a href="./mod/core.html#files" class="directive"><code class="directive"><Files></code></a>. When applying directives to objects
+that do not reside in the filesystem (such as a webpage generated from
+a database), use <a href="./mod/core.html#location" class="directive"><code class="directive"><Location></code></a>.</p>
+
+<p>It is important to never use <a href="./mod/core.html#location" class="directive"><code class="directive"><Location></code></a> when trying to restrict
+access to objects in the filesystem. This is because many
+different webspace locations (URLs) could map to the same filesystem
+location, allowing your restrictions to be circumvented.
+For example, consider the following configuration:</p>
+
+<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
+<Location /dir/><br>
+Order allow,deny<br>
+Deny from all<br>
+</Location>
+</code></td></tr></table></blockquote>
+
+<p>This works fine if the request is for
+<code>http://yoursite.example.com/dir/</code>. But what if you are on
+a case-insensitive filesystem? Then your restriction could be easily
+circumvented by requesting
+<code>http://yoursite.example.com/DIR/</code>. The <a href="./mod/core.html#directory" class="directive"><code class="directive"><Directory></code></a> directive, in
+contrast, will apply to any content served from that location,
+regardless of how it is called. (An exception is filesystem links.
+The same directory can be placed in more than one part of the
+filesystem using symbolic links. The <a href="./mod/core.html#directory" class="directive"><code class="directive"><Directory></code></a> directive will follow the symbolic
+link without resetting the pathname. Therefore, for the highest level
+of security, symbolic links should be disabled with the appropriate
+<a href="./mod/core.html#options" class="directive"><code class="directive">Options</code></a> directive.)</p>
+
+<p>If you are, perhaps, thinking that none of this applies to you
+because you use a case-sensitive filesystem, remember that there are
+many other ways to map multiple webspace locations to the same
+filesystem location. Therefore you should always use the filesystem
+containers when you can. There is, however, one exception to this
+rule. Putting configuration restrictions in a <code><Location
+/></code> section is perfectly safe because this section will apply
+to all requests regardless of the specific URL.</p>
+
+
+<h2><a name="virtualhost">Virtual Hosts</a></h2>
+
+<p>The <a href="./mod/core.html#virtualhost" class="directive"><code class="directive"><VirtualHost></code></a>
+container encloses directives that apply to specific hosts.
+This is useful when serving multiple hosts from the same machine
+with a different configuration for each. For more information,
+see the <a href="vhosts/">Virtual Host Documentation</a>.</p>
+<h2><a name="proxy">Proxy</a></h2>
+
+<p>The <a href="./mod/proxy.html#proxy" class="directive"><code class="directive"><Proxy></code></a>
+container applies enclosed configuration directives only
+to sites accessed through <code><a href="./mod/mod_proxy.html">mod_proxy</a></code>'s proxy server
+that match the specified URL. For example, the following configuration
+will prevent the proxy server from being used to access the
+<code>cnn.com</code> website.</p>
+
+<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
+<Proxy http://cnn.com/*><br>
+Order allow,deny<br>
+Deny from all<br>
+</Proxy>
+</code></td></tr></table></blockquote>
+<h2><a name="whatwhere">What Directives are Allowed?</a></h2>
+
+<p>To find out what directives are allowed in what types of
+configuration sections, check the <a href="mod/directive-dict.html#Context">Context</a> of the directive.
+Everything that is allowed in
+<a href="./mod/core.html#directory" class="directive"><code class="directive"><Directory></code></a>
+sections is also syntactically allowed in
+<a href="./mod/core.html#directorymatch" class="directive"><code class="directive"><DirectoryMatch></code></a>,
+<a href="./mod/core.html#files" class="directive"><code class="directive"><Files></code></a>,
+<a href="./mod/core.html#filesmatch" class="directive"><code class="directive"><FilesMatch></code></a>,
+<a href="./mod/core.html#location" class="directive"><code class="directive"><Location></code></a>,
+<a href="./mod/core.html#locationmatch" class="directive"><code class="directive"><LocationMatch></code></a>,
+and
+<a href="./mod/proxy.html#proxy" class="directive"><code class="directive"><Proxy></code></a>
+sections. There are some exceptions, however.</p>
+
+<ul>
+<li>The <a href="./mod/core.html#allowoverride" class="directive"><code class="directive">AllowOverride</code></a> directive
+works only in <a href="./mod/core.html#directory" class="directive"><code class="directive"><Directory></code></a>
+sections.</li>
+
+<li>The <code>FollowSymLinks</code> and
+<code>SymLinksIfOwnerMatch</code> <a href="./mod/core.html#options" class="directive"><code class="directive">Options</code></a> work only in <a href="./mod/core.html#directory" class="directive"><code class="directive"><Directory></code></a> sections or
+<code>.htaccess</code> files.</li>
+
+<li>The <a href="./mod/core.html#options" class="directive"><code class="directive">Options</code></a> directive cannot
+be used in <a href="./mod/core.html#files" class="directive"><code class="directive"><Files></code></a>
+and <a href="./mod/core.html#filesmatch" class="directive"><code class="directive"><FilesMatch></code></a>
+sections.</li>
+</ul>
+<h2><a name="mergin">How the sections are merged</a></h2>
+
+<p>The configuration sections are applied in a very particular order.
+Since this can have important effects on how configuration directives
+are interpreted, it is important to understand how this works.</p>
+
+ <p>The order of merging is:</p>
+
+ <ol>
+ <li> <a href="./mod/core.html#directory" class="directive"><code class="directive"><Directory></code></a> (except regular expressions)
+ and .htaccess done simultaneously (with .htaccess, if allowed,
+ overriding <a href="./mod/core.html#directory" class="directive"><code class="directive"><Directory></code></a>)</li>
+
+ <li><a href="./mod/core.html#directorymatch" class="directive"><code class="directive"><DirectoryMatch></code></a>
+ (and <code><Directory ~></code>)</li>
+
+ <li><a href="./mod/core.html#files" class="directive"><code class="directive"><Files></code></a> and <a href="./mod/core.html#filesmatch" class="directive"><code class="directive"><FilesMatch></code></a> done
+ simultaneously</li>
+
+ <li><a href="./mod/core.html#location" class="directive"><code class="directive"><Location></code></a>
+ and <a href="./mod/core.html#locationmatch" class="directive"><code class="directive"><LocationMatch></code></a> done simultaneously</li>
+ </ol>
+
+ <p>Apart from <a href="./mod/core.html#directory" class="directive"><code class="directive"><Directory></code></a>, each group is processed in
+ the order that they appear in the configuration files. <a href="./mod/core.html#directory" class="directive"><code class="directive"><Directory></code></a> (group 1 above)
+ is processed in the order shortest directory component to longest.
+ So for example, <code><Directory /var/web/dir></code> will
+ be processed before <code><Directory
+ /var/web/dir/subdir></code>. If multiple <a href="./mod/core.html#directory" class="directive"><code class="directive"><Directory></code></a> sections apply
+ to the same directory they are processed in the configuration file
+ order. Configurations included via the <a href="./mod/core.html#include" class="directive"><code class="directive">Include</code></a> directive will be treated as if
+ they were inside the including file at the location of the
+ <a href="./mod/core.html#include" class="directive"><code class="directive">Include</code></a> directive.</p>
+
+ <p>Sections inside <a href="./mod/core.html#virtualhost" class="directive"><code class="directive"><VirtualHost></code></a> sections
+ are applied <em>after</em> the corresponding sections outside
+ the virtual host definition. This allows virtual hosts to
+ override the main server configuration.</p>
+
+ <p>Later sections override earlier ones.</p>
+
+<blockquote><table><tr><td bgcolor="#e0e5f5"><p align="center"><strong>Technical Note</strong></p>
+ There is actually a
<code><Location></code>/<code><LocationMatch></code>
sequence performed just before the name translation phase
(where <code>Aliases</code> and <code>DocumentRoots</code>
are used to map URLs to filenames). The results of this
sequence are completely thrown away after the translation has
- completed.</li>
- </ul>
- <!--#include virtual="footer.html" -->
- </body>
-</html>
+ completed.
+</td></tr></table></blockquote>
+
+<h3><a name="merge-examples">Some Examples</a></h3>
+<p>Below is an artificial example to show the order of
+merging. Assuming they all apply to the request, the directives in
+this example will be applied in the order A > B > C > D >
+E.</p>
+
+<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
+<Location /><br>
+E<br>
+</Location><br>
+<br>
+<Files f.html><br>
+D<br>
+</Files><br>
+<br>
+<VirtualHost *><br>
+<Directory /a/b><br>
+B<br>
+</Directory><br>
+</VirtualHost><br>
+<br>
+<DirectoryMatch "^.*b$"><br>
+C<br>
+</DirectoryMatch><br>
+<br>
+<Directory /a/b><br>
+A<br>
+</Directory><br>
+<br>
+</code></td></tr></table></blockquote>
+
+<p>For a more concrete example, consider the following. Regardless of
+any access restrictions placed in <a href="./mod/core.html#directory" class="directive"><code class="directive"><Directory></code></a> sections, the <a href="./mod/core.html#location" class="directive"><code class="directive"><Location></code></a> section will be
+evaluated last and will allow unrestricted access to the server. In
+other words, order of merging is important, so be careful!</p>
+
+<blockquote><table cellpadding="10"><tr><td bgcolor="#eeeeee"><code>
+<Location /><br>
+Order deny,allow<br>
+Allow from all<br>
+</Location><br>
+<br>
+# Woops! This <Directory> section will have no effect<br>
+<Directory /><br>
+Order allow,deny<br>
+Allow from all<br>
+Deny from badguy.example.com<br>
+</Directory>
+</code></td></tr></table></blockquote>
+
+
+
+<hr></blockquote><h3 align="center">Apache HTTP Server Version 2.0</h3><a href="./"><img src="./images/index.gif" alt="Index"></a><a href="./"><img src="./images/home.gif" alt="Home"></a></body></html>
\ No newline at end of file
1.1 httpd-2.0/docs/manual/sections.xml
Index: sections.xml
===================================================================
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE manualpage SYSTEM "./style/manualpage.dtd">
<?xml-stylesheet type="text/xsl" href="./style/manual.en.xsl"?>
<manualpage>
<relativepath href="."/>
<title>Configuration Sections</title>
<summary> <p>Directives in the <a
href="configuring.html">configuration files</a> may apply to the
entire server, or they may be restricted to apply only to particular
directories, files, hosts, or URLs. This document describes how to
use configuration section containers or <code>.htaccess</code> files
to change the scope of other configuration directives.</p>
</summary>
<section id="types"><title>Types of Configuration Section Containers</title>
<related>
<modulelist>
<module>core</module>
<module>mod_proxy</module>
</modulelist>
<directivelist>
<directive type="section" module="core">Directory</directive>
<directive type="section" module="core">DirectoryMatch</directive>
<directive type="section" module="core">Files</directive>
<directive type="section" module="core">FilesMatch</directive>
<directive type="section" module="core">IfDefine</directive>
<directive type="section" module="core">IfModule</directive>
<directive type="section" module="core">Location</directive>
<directive type="section" module="core">LocationMatch</directive>
<directive type="section" module="proxy">Proxy</directive>
<directive type="section" module="core">VirtualHost</directive>
</directivelist>
</related>
<p>There are two basic types of containers. Most containers are
evaluated for each request. The enclosed directives are applied only
for those requests that match the containers. The <directive
type="section" module="core">IfDefine</directive> and <directive
type="section" module="core">IfModule</directive> containers, on the
other hand, are evaluated only at server startup and restart. If
their conditions are true at startup, then the enclosed directives
will apply to all requests. If the conditions are not true, the
enclosed directives will be ignored.</p>
<p>The <directive type="section" module="core">IfDefine</directive> directive
encloses directives that will only be applied if an appropriate
parameter is defined on the <code>httpd</code> command line. For example,
with the following configuration, all requests will be redirected
to another site only if the server is started using
<code>httpd -DClosedForNow</code>:</p>
<example>
<IfDefine ClosedForNow><br />
Redirect / http://otherserver.example.com/<br />
</IfDefine>
</example>
<p>The <directive type="section" module="core">IfModule</directive>
directive is very similar, except it encloses directives that will
only be applied if a particular module is available in the server.
The module must either be statically compiled in the server, or it
must be dynamically compiled and its <directive
module="mod_so">LoadModule</directive> line must be earlier in the
configuration file. This directive should only be used if you need
your configuration file to work whether or not certain modules are
installed. It should not be used to enclose directives that you want
to work all the time, because it can suppress useful error messages
about missing modules.</p>
<p>In the following example, the <directive
module="mod_mime_magic">MimeMagicFiles</directive> directive will be
applied only if <module>mod_mime_magic</module> is available.</p>
<example>
<IfModule mod_mime_magic.c><br />
MimeMagicFile conf/magic<br />
</IfModule>
</example>
<p>Both <directive type="section" module="core">IfDefine</directive>
and <directive type="section" module="core">IfModule</directive>
can apply negative conditions by preceding their test with "!".
Also, these sections can be nested to achieve more complex
restrictions.</p>
</section>
<section id="file-and-web"><title>Filesystem and Webspace</title>
<p>The most commonly used configuration section containers are the
ones that change the configuration of particular places in the
filesystem or webspace. First, it is important to understand the
difference between the two. The filesystem is the view of your disks
as seen by your operating system. For example, in a default install,
Apache resides at <code>/usr/local/apache2</code> in the Unix
filesystem or <code>"c:/Program Files/Apache Group/Apache2"</code> in
the Windows filesystem. (Note that forward slashes should always be
used as the path separator in Apache, even for Windows.) In contrast,
the webspace is the view of your site as delivered by the web server
and seen by the client. So the path <code>/dir/</code> in the
webspace corresponds to the path
<code>/usr/local/apache2/htdocs/dir/</code> in the filesystem of a
default Apache install on Unix. The webspace need not map directly to
the filesystem, since webpages may be generated dynamically
from databases or other locations.</p>
<section id="filesystem"><title>Filesystem Containers</title>
<p>The <directive type="section" module="core">Directory</directive>
and <directive type="section" module="core">Files</directive>
directives, along with their regex counterparts, apply directives to
parts of the filesystem. Directives enclosed in a <directive
type="section" module="core">Directory</directive> section apply to
the named filesystem directory and all subdirectories of that
directory. The same effect can be obtained using <a
href="howto/htaccess.html">.htaccess files</a>. For example, in the
following configuration, directory indexes will be enabled for the
<code>/var/web/dir1</code> directory and all subdirectories.</p>
<example>
<Directory /var/web/dir1><br />
Options +Indexes<br />
</Directory>
</example>
<p>Directives enclosed in a <directive type="section"
module="core">Files</directive> section apply to any file with
the specified name, regardless of what directory it lies in.
So for example, the following configuration directives will,
when placed in the main section of the configuration file,
deny access to any file named <code>private.html</code> regardless
of where it is found.</p>
<example>
<Files private.html><br />
Order allow,deny<br />
Deny from all<br />
</Files>
</example>
<p>To address files found in a particular part of the filesystem, the
<directive type="section" module="core">Files</directive> and
<directive type="section" module="core">Directory</directive> sections
can be combined. For example, the following configuration will deny
access to <code>/var/web/dir1/private.html</code>,
<code>/var/web/dir1/subdir2/private.html</code>,
<code>/var/web/dir1/subdir3/private.html</code>, and any other instance
of <code>private.html</code> found under the <code>/var/web/dir1/</code>
directory.</p>
<example>
<Directory /var/web/dir1><br />
<Files private.html><br />
Order allow,deny<br />
Deny from all<br />
</Files><br />
</Directory>
</example>
</section>
<section id="webspace"><title>Webspace Containers</title>
<p>The <directive type="section" module="core">Location</directive>
directive and its regex counterpart, on the other hand, change the
configuration for content in the webspace. For example, the following
configuration prevents access to any URL-path that begins in /private.
In particular, it will apply to requests for
<code>http://yoursite.example.com/private</code>,
<code>http://yoursite.example.com/private123</code>, and
<code>http://yoursite.example.com/private/dir/file.html</code> as well
as any other requests starting with the <code>/private</code> string.</p>
<example>
<Location /private><br />
Order Allow,Deny<br />
Deny from all<br />
</Location>
</example>
<p>The <directive type="section" module="core">Location</directive>
directive need not have anything to do with the filesystem.
For example, the following example shows how to map a particular
URL to an internal Apache handler provided by <module>mod_status</module>.
No file called <code>server-status</code> needs to exist in the
filesystem.</p>
<example>
<Location /server-status><br />
SetHandler server-status<br />
</Location>
</example>
</section>
<section id="wildcards"><title>Wildcards and Regular Expressions</title>
<p>The <directive type="section" module="core">Directory</directive>,
<directive type="section" module="core">Files</directive>, and
<directive type="section" module="core">Location</directive>
directives can each use the shell-style wildcard characters "?" to
match any single character, "*" to match any set of characters, and
character classes like [a-zA-Z] to match particular characters. This
is useful to apply the same configuration to a group of filesystem or
webspace locations. If even more flexible matching is required, each
container has a regular-expression (regex) counterpart <directive
type="section" module="core">DirectoryMatch</directive>, <directive
type="section" module="core">FilesMatch</directive>, and <directive
type="section" module="core">LocationMatch</directive> that allow
perl-compatible<a href="glossary.html#regex">regular expressions</a>
to be used in choosing the matches. But see the section below on
configuration merging to find out how using regex sections will change
how directives are applied.</p>
<p>A non-regex wildcard section that changes the configuration of
all user directories could look as follows:</p>
<example>
<Directory /home/*/public_html><br />
Options Indexes<br />
</Directory>
</example>
<p>Using regex sections, we can deny access to many types of image files
at once:</p>
<example>
<FilesMatch \.(?i:gif|jpe?g|png)$><br />
Order allow,deny<br />
Deny from all<br />
</FilesMatch>
</example>
</section>
<section id="whichwhen"><title>What to use When</title>
<p>Choosing between filesystem containers and webspace containers is
actually quite easy. When applying directives to objects that reside
in the filesystem always use <directive type="section"
module="core">Directory</directive> or <directive type="section"
module="core">Files</directive>. When applying directives to objects
that do not reside in the filesystem (such as a webpage generated from
a database), use <directive type="section"
module="core">Location</directive>.</p>
<p>It is important to never use <directive type="section"
module="core">Location</directive> when trying to restrict
access to objects in the filesystem. This is because many
different webspace locations (URLs) could map to the same filesystem
location, allowing your restrictions to be circumvented.
For example, consider the following configuration:</p>
<example>
<Location /dir/><br />
Order allow,deny<br />
Deny from all<br />
</Location>
</example>
<p>This works fine if the request is for
<code>http://yoursite.example.com/dir/</code>. But what if you are on
a case-insensitive filesystem? Then your restriction could be easily
circumvented by requesting
<code>http://yoursite.example.com/DIR/</code>. The <directive
type="section" module="core">Directory</directive> directive, in
contrast, will apply to any content served from that location,
regardless of how it is called. (An exception is filesystem links.
The same directory can be placed in more than one part of the
filesystem using symbolic links. The <directive type="section"
module="core">Directory</directive> directive will follow the symbolic
link without resetting the pathname. Therefore, for the highest level
of security, symbolic links should be disabled with the appropriate
<directive module="core">Options</directive> directive.)</p>
<p>If you are, perhaps, thinking that none of this applies to you
because you use a case-sensitive filesystem, remember that there are
many other ways to map multiple webspace locations to the same
filesystem location. Therefore you should always use the filesystem
containers when you can. There is, however, one exception to this
rule. Putting configuration restrictions in a <code><Location
/></code> section is perfectly safe because this section will apply
to all requests regardless of the specific URL.</p>
</section>
</section>
<section id="virtualhost"><title>Virtual Hosts</title>
<p>The <directive type="section" module="core">VirtualHost</directive>
container encloses directives that apply to specific hosts.
This is useful when serving multiple hosts from the same machine
with a different configuration for each. For more information,
see the <a href="vhosts/">Virtual Host Documentation</a>.</p>
</section>
<section id="proxy"><title>Proxy</title>
<p>The <directive type="section" module="proxy">Proxy</directive>
container applies enclosed configuration directives only
to sites accessed through <module>mod_proxy</module>'s proxy server
that match the specified URL. For example, the following configuration
will prevent the proxy server from being used to access the
<code>cnn.com</code> website.</p>
<example>
<Proxy http://cnn.com/*><br />
Order allow,deny<br />
Deny from all<br />
</Proxy>
</example>
</section>
<section id="whatwhere"><title>What Directives are Allowed?</title>
<p>To find out what directives are allowed in what types of
configuration sections, check the <a
href="mod/directive-dict.html#Context">Context</a> of the directive.
Everything that is allowed in
<directive type="section" module="core">Directory</directive>
sections is also syntactically allowed in
<directive type="section" module="core">DirectoryMatch</directive>,
<directive type="section" module="core">Files</directive>,
<directive type="section" module="core">FilesMatch</directive>,
<directive type="section" module="core">Location</directive>,
<directive type="section" module="core">LocationMatch</directive>,
and
<directive type="section" module="proxy">Proxy</directive>
sections. There are some exceptions, however.</p>
<ul>
<li>The <directive module="core">AllowOverride</directive> directive
works only in <directive type="section" module="core">Directory</directive>
sections.</li>
<li>The <code>FollowSymLinks</code> and
<code>SymLinksIfOwnerMatch</code> <directive
module="core">Options</directive> work only in <directive
type="section" module="core">Directory</directive> sections or
<code>.htaccess</code> files.</li>
<li>The <directive module="core">Options</directive> directive cannot
be used in <directive type="section" module="core">Files</directive>
and <directive type="section" module="core">FilesMatch</directive>
sections.</li>
</ul>
</section>
<section id="mergin"><title>How the sections are merged</title>
<p>The configuration sections are applied in a very particular order.
Since this can have important effects on how configuration directives
are interpreted, it is important to understand how this works.</p>
<p>The order of merging is:</p>
<ol>
<li> <directive type="section"
module="core">Directory</directive> (except regular expressions)
and .htaccess done simultaneously (with .htaccess, if allowed,
overriding <directive type="section"
module="core">Directory</directive>)</li>
<li><directive type="section" module="core">DirectoryMatch</directive>
(and <code><Directory ~></code>)</li>
<li><directive type="section"
module="core">Files</directive> and <directive
type="section" module="core">FilesMatch</directive> done
simultaneously</li>
<li><directive type="section" module="core">Location</directive>
and <directive type="section"
module="core">LocationMatch</directive> done simultaneously</li>
</ol>
<p>Apart from <directive type="section"
module="core">Directory</directive>, each group is processed in
the order that they appear in the configuration files. <directive
type="section" module="core">Directory</directive> (group 1 above)
is processed in the order shortest directory component to longest.
So for example, <code><Directory /var/web/dir></code> will
be processed before <code><Directory
/var/web/dir/subdir></code>. If multiple <directive
type="section" module="core">Directory</directive> sections apply
to the same directory they are processed in the configuration file
order. Configurations included via the <directive
module="core">Include</directive> directive will be treated as if
they were inside the including file at the location of the
<directive module="core">Include</directive> directive.</p>
<p>Sections inside <directive type="section"
module="core">VirtualHost</directive> sections
are applied <em>after</em> the corresponding sections outside
the virtual host definition. This allows virtual hosts to
override the main server configuration.</p>
<p>Later sections override earlier ones.</p>
<note><title>Technical Note</title>
There is actually a
<code><Location></code>/<code><LocationMatch></code>
sequence performed just before the name translation phase
(where <code>Aliases</code> and <code>DocumentRoots</code>
are used to map URLs to filenames). The results of this
sequence are completely thrown away after the translation has
completed.
</note>
<section id="merge-examples"><title>Some Examples</title>
<p>Below is an artificial example to show the order of
merging. Assuming they all apply to the request, the directives in
this example will be applied in the order A > B > C > D >
E.</p>
<example>
<Location /><br />
E<br />
</Location><br />
<br />
<Files f.html><br />
D<br />
</Files><br />
<br />
<VirtualHost *><br />
<Directory /a/b><br />
B<br />
</Directory><br />
</VirtualHost><br />
<br />
<DirectoryMatch "^.*b$"><br />
C<br />
</DirectoryMatch><br />
<br />
<Directory /a/b><br />
A<br />
</Directory><br />
<br />
</example>
<p>For a more concrete example, consider the following. Regardless of
any access restrictions placed in <directive module="core"
type="section">Directory</directive> sections, the <directive
module="core" type="section">Location</directive> section will be
evaluated last and will allow unrestricted access to the server. In
other words, order of merging is important, so be careful!</p>
<example>
<Location /><br />
Order deny,allow<br />
Allow from all<br />
</Location><br />
<br />
# Woops! This <Directory> section will have no effect<br />
<Directory /><br />
Order allow,deny<br />
Allow from all<br />
Deny from badguy.example.com<br />
</Directory>
</example>
</section>
</section>
</manualpage>