<summary>
-<p>This document supplements the <module>mod_rewrite</module>
-<a href="../mod/mod_rewrite.html">reference documentation</a>. It describes
-how you can use <module>mod_rewrite</module> to control access to
-various resources, and other related techniques.
-This includes many examples of common uses of <module>mod_rewrite</module>,
-including detailed descriptions of how each works.</p>
-
-<note type="warning">Note that many of these examples won't work unchanged in your
-particular server configuration, so it's important that you understand
-them, rather than merely cutting and pasting the examples into your
-configuration.</note>
+<note type="warning">This document has been deprecated. Its content has
+been reorganized into the
+<a href="avoid.html">When not to use mod_rewrite</a> document, since
+the recipes here are better accomplished using other Apache httpd
+features. This page will be removed in a future version of this
+documentation.</note>
+
+<ul>
+<li><strong>Forbidding image hotlinking</strong> - See
+ <a href="avoid.html#blocked-inline-images">When not to use mod_rewrite</a></li>
+<li><strong>Blocking of robots</strong> - See
+ <a href="avoid.html#blocking-of-robots">When not to use mod_rewrite</a></li>
+<li><strong>Denying hosts in a reject list</strong> - See
+ <a href="avoid.html#host-deny">When not to use mod_rewrite</a></li>
+</ul>
</summary>
-<seealso><a href="../mod/mod_rewrite.html">Module documentation</a></seealso>
-<seealso><a href="intro.html">mod_rewrite introduction</a></seealso>
-<seealso><a href="remapping.html">Redirection and remapping</a></seealso>
-<!-- <seealso><a href="access.html">Controlling access</a></seealso> -->
-<seealso><a href="vhosts.html">Virtual hosts</a></seealso>
-<seealso><a href="proxy.html">Proxying</a></seealso>
-<seealso><a href="rewritemap.html">Using RewriteMap</a></seealso>
-<seealso><a href="advanced.html">Advanced techniques</a></seealso>
-<seealso><a href="avoid.html">When not to use mod_rewrite</a></seealso>
-
- <section id="blocked-inline-images">
-
- <title>Forbidding Image "Hotlinking"</title>
-
- <dl>
- <dt>Description:</dt>
-
- <dd>
- <p>The following technique forbids the practice of other sites
- including your images inline in their pages. This practice is
- often referred to as "hotlinking", and results in
- your bandwidth being used to serve content for someone else's
- site.</p>
- </dd>
-
- <dt>Solution:</dt>
-
- <dd>
- <p>This technique relies on the value of the
- <code>HTTP_REFERER</code> variable, which is optional. As
- such, it's possible for some people to circumvent this
- limitation. However, most users will experience the failed
- request, which should, over time, result in the image being
- removed from that other site.</p>
- <p>There are several ways that you can handle this
- situation.</p>
-
- <p>In this first example, we simply deny the request, if it didn't
- initiate from a page on our site. For the purpose of this example,
- we assume that our site is <code>www.example.com</code>.</p>
-
-<!-- TODO: Add discussion here of why we have !^$ in there. -->
-
-<highlight language="config">
-RewriteCond "%{HTTP_REFERER}" "!^$"
-RewriteCond "%{HTTP_REFERER}" "!www.example.com" [NC]
-RewriteRule "\.(gif|jpg|png)$" "-" [F,NC]
-</highlight>
-
- <p>In this second example, instead of failing the request, we display
- an alternate image instead.</p>
-
-<highlight language="config">
-RewriteCond "%{HTTP_REFERER}" "!^$"
-RewriteCond "%{HTTP_REFERER}" "!www.example.com" [NC]
-RewriteRule "\.(gif|jpg|png)$" "/images/go-away.png" [R,NC]
-</highlight>
-
- <p>In the third example, we redirect the request to an image on some
- other site.</p>
-
-<highlight language="config">
-RewriteCond "%{HTTP_REFERER}" "!^$"
-RewriteCond "%{HTTP_REFERER}" "!www.example.com" [NC]
-RewriteRule "\.(gif|jpg|png)$" "http://other.example.com/image.gif" [R,NC]
-</highlight>
-
- <p>Of these techniques, the last two tend to be the most effective
- in getting people to stop hotlinking your images, because they will
- simply not see the image that they expected to see.</p>
-
- </dd>
-
- <dt>Discussion:</dt>
-
- <dd>
- <p>If all you wish to do is deny access to the resource, rather
- than redirecting that request elsewhere, this can be
- accomplished without the use of <module>mod_rewrite</module>:</p>
-
- <highlight language="config">
-SetEnvIf Referer example\.com localreferer
-<FilesMatch "\.(jpg|png|gif)$">
- Require env localreferer
-</FilesMatch>
- </highlight>
- </dd>
- </dl>
-
- </section>
-
- <section id="blocking-of-robots">
-
- <title>Blocking of Robots</title>
-
- <dl>
- <dt>Description:</dt>
-
- <dd>
- <p>
- In this recipe, we discuss how to block persistent requests from
- a particular robot, or user agent.</p>
-
- <p>The standard for robot exclusion defines a file,
- <code>/robots.txt</code> that specifies those portions of your
- website where you wish to exclude robots. However, some robots
- do not honor these files.
- </p>
-
- <p>Note that there are methods of accomplishing this which do
- not use <module>mod_rewrite</module>. Note also that any technique that relies on
- the clients <code>USER_AGENT</code> string can be circumvented
- very easily, since that string can be changed.</p>
- </dd>
-
- <dt>Solution:</dt>
-
- <dd>
- <p>We use a ruleset that specifies the directory to be
- protected, and the client <code>USER_AGENT</code> that
- identifies the malicious or persistent robot.</p>
-
- <p>In this example, we are blocking a robot called
- <code>NameOfBadRobot</code> from a location
- <code>/secret/files</code>. You may also specify an IP address
- range, if you are trying to block that user agent only from the
- particular source.</p>
-
-<highlight language="config">
-RewriteCond "%{HTTP_USER_AGENT}" "^NameOfBadRobot"
-RewriteCond "%{REMOTE_ADDR}" "=123\.45\.67\.[8-9]"
-RewriteRule "^/secret/files/" "-" [F]
-</highlight>
- </dd>
-
- <dt>Discussion:</dt>
-
- <dd>
- <p>
- Rather than using <module>mod_rewrite</module> for this, you can accomplish the
- same end using alternate means, as illustrated here:
- </p>
- <highlight language="config">
-SetEnvIfNoCase User-Agent ^NameOfBadRobot goaway
-<Location "/secret/files">
- <RequireAll>
- Require all granted
- Require not env goaway
- </RequireAll>
-</Location>
- </highlight>
- <p>
- As noted above, this technique is trivial to circumvent, by simply
- modifying the <code>USER_AGENT</code> request header. If you
- are experiencing a sustained attack, you should consider blocking
- it at a higher level, such as at your firewall.
- </p>
-
- </dd>
-
- </dl>
-
- </section>
-
-<section id="host-deny">
-
- <title>Denying Hosts in a Reject List</title>
-
- <dl>
- <dt>Description:</dt>
-
- <dd>
- <p>We wish to maintain a list of hosts, rather like
- <code>hosts.deny</code>, and have those hosts blocked from
- accessing our server.</p>
- </dd>
-
- <dt>Solution:</dt>
-
- <dd>
-<highlight language="config">
-RewriteEngine on
-RewriteMap hosts-deny "txt:/path/to/hosts.deny"
-RewriteCond "${hosts-deny:%{REMOTE_ADDR}|NOT-FOUND}" "!=NOT-FOUND" [OR]
-RewriteCond "${hosts-deny:%{REMOTE_HOST}|NOT-FOUND}" "!=NOT-FOUND"
-RewriteRule "^" "-" [F]
-</highlight>
-
-<example>
-##<br />
-## hosts.deny<br />
-##<br />
-## ATTENTION! This is a map, not a list, even when we treat it as such.<br />
-## mod_rewrite parses it for key/value pairs, so at least a<br />
-## dummy value "-" must be present for each entry.<br />
-##<br />
-<br />
-193.102.180.41 -<br />
-bsdti1.sdm.de -<br />
-192.76.162.40 -<br />
-</example>
- </dd>
-
- <dt>Discussion:</dt>
- <dd>
- <p>
- The second RewriteCond assumes that you have HostNameLookups turned
- on, so that client IP addresses will be resolved. If that's not the
- case, you should drop the second RewriteCond, and drop the
- <code>[OR]</code> flag from the first RewriteCond.
- </p>
- </dd>
- </dl>
-
-</section>
-
-<section id="referer-deflector">
-
- <title>Referer-based Deflector</title>
-
- <dl>
- <dt>Description:</dt>
-
- <dd>
- <p>Redirect requests based on the Referer from which the request
- came, with different targets per Referer.</p>
- </dd>
-
- <dt>Solution:</dt>
-
- <dd>
- <p>The following ruleset uses a map file to associate each Referer
- with a redirection target.</p>
-
-<highlight language="config">
-RewriteMap deflector "txt:/path/to/deflector.map"
-
-RewriteCond "%{HTTP_REFERER}" !=""
-RewriteCond "${deflector:%{HTTP_REFERER}}" =-
-RewriteRule "^" "%{HTTP_REFERER}" [R,L]
-
-RewriteCond "%{HTTP_REFERER}" !=""
-RewriteCond "${deflector:%{HTTP_REFERER}|NOT-FOUND}" "!=NOT-FOUND"
-RewriteRule "^" "${deflector:%{HTTP_REFERER}}" [R,L]
-</highlight>
-
- <p>The map file lists redirection targets for each referer, or, if
- we just wish to redirect back to where they came from, a "-" is
- placed in the map:</p>
-
-<highlight language="config">
-##
-## deflector.map
-##
-
-http://badguys.example.com/bad/index.html -
-http://badguys.example.com/bad/index2.html -
-http://badguys.example.com/bad/index3.html http://somewhere.example.com/
-</highlight>
-
- </dd>
- </dl>
-
-</section>
</manualpage>
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