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diff --git a/APACHE_1_3_42/htdocs/manual/mod/mod_access.html.en b/APACHE_1_3_42/htdocs/manual/mod/mod_access.html.en new file mode 100644 index 0000000000..eeb70dd739 --- /dev/null +++ b/APACHE_1_3_42/htdocs/manual/mod/mod_access.html.en @@ -0,0 +1,374 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" + "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> + +<html xmlns="http://www.w3.org/1999/xhtml"> + <head> + <meta name="generator" content="HTML Tidy, see www.w3.org" /> + + <title>Apache module mod_access</title> + </head> + <!-- Background white, links blue (unvisited), navy (visited), red (active) --> + + <body bgcolor="#FFFFFF" text="#000000" link="#0000FF" + vlink="#000080" alink="#FF0000"> + <!--#include virtual="header.html" --> + + <h1 align="center">Module mod_access</h1> + + <p>This module provides access control based on client + hostname, IP address, or other characteristics of the client + request.</p> + + <p><a href="module-dict.html#Status" + rel="Help"><strong>Status:</strong></a> Base<br /> + <a href="module-dict.html#SourceFile" + rel="Help"><strong>Source File:</strong></a> mod_access.c<br /> + <a href="module-dict.html#ModuleIdentifier" + rel="Help"><strong>Module Identifier:</strong></a> + access_module</p> + + <h2>Summary</h2> + + <p>The directives provided by mod_access are used in <code><a + href="core.html#directory"><Directory></a>, <a + href="core.html#files"><Files></a>,</code> and <code><a + href="core.html#location"><Location></a></code> sections + as well as <code><a + href="core.html#accessfilename">.htaccess</a></code> files to + control access to particular parts of the server. Access can be + controlled based on the client hostname, IP address, or other + characteristics of the client request, as captured in <a + href="../env.html">environment variables</a>. The + <code>Allow</code> and <code>Deny</code> directives are used to + specify which clients are or are not allowed access to the + server, while the <code>Order</code> directive sets the default + access state, and configures how the <code>Allow</code> and + <code>Deny</code> directives interact with each other.</p> + + <p>Both host-based access restrictions and password-based + authentication may be implemented simultaneously. In that case, + the <a href="core.html#satisfy">Satisfy</a> directive is used + to determine how the two sets of restrictions interact.</p> + + <p>In general, access restriction directives apply to all + access methods (<code>GET</code>, <code>PUT</code>, + <code>POST</code>, etc). This is the desired behavior in most + cases. However, it is possible to restrict some methods, while + leaving other methods unrestricted, by enclosing the directives + in a <a href="core.html#limit"><Limit></a> section.</p> + + <h2>Directives</h2> + + <ul> + <li><a href="#allow">Allow</a></li> + + <li><a href="#deny">Deny</a></li> + + <li><a href="#order">Order</a></li> + </ul> + + <p>See also <a href="core.html#satisfy">Satisfy</a> and <a + href="core.html#require">Require</a>.</p> + <hr /> + + <h2><a id="allow" name="allow">Allow</a> <a id="allowfromenv" + name="allowfromenv">directive</a></h2> + + <p> + <a href="directive-dict.html#Syntax" + rel="Help"><strong>Syntax:</strong></a> Allow from + all|<em>host</em>|env=<em>env-variable</em> + [<em>host</em>|env=<em>env-variable</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> Limit<br /> + <a href="directive-dict.html#Status" + rel="Help"><strong>Status:</strong></a> Base<br /> + <a href="directive-dict.html#Module" + rel="Help"><strong>Module:</strong></a> mod_access</p> + + <p>The <code>Allow</code> directive affects which hosts can + access an area of the server. Access can be controlled by + hostname, IP address, IP address range, or other + characteristics of the client request captured in environment + variables.</p> + + <p>The first argument to this directive is always + <code>from</code>. The subsequent arguments can take three + different forms. If <code>Allow from all</code> is specified, + then all hosts are allowed access, subject to the configuration + of the <code>Deny</code> and <code>Order</code> directives as + discussed below. To allow only particular hosts or groups of + hosts to access the server, the <em>host</em> can be specified + in any of the following formats:</p> + + <dl> + <dt>A (partial) domain-name</dt> + + <dd>Example: <code>Allow from apache.org</code><br /> + Hosts whose names match, or end in, this string are allowed + access. Only complete components are matched, so the above + example will match <code>foo.apache.org</code> but it will + not match <code>fooapache.org</code>. This configuration will + cause the server to perform a double reverse DNS lookup on the + client IP address, regardless of the setting of the <a + href="core.html#hostnamelookups">HostnameLookups</a> + directive. It will do a reverse DNS lookup on the IP address to + find the associated hostname, and then do a forward lookup on + the hostname to assure that it matches the original IP address. + Only if the forward and reverse DNS are consistent and the + hostname matches will access be allowed.</dd> + + <dt>A full IP address</dt> + + <dd>Example: <code>Allow from 10.1.2.3</code><br /> + An IP address of a host allowed access</dd> + + <dt>A partial IP address</dt> + + <dd>Example: <code>Allow from 10.1</code><br /> + The first 1 to 3 bytes of an IP address, for subnet + restriction.</dd> + + <dt>A network/netmask pair</dt> + + <dd>Example: <code>Allow from + 10.1.0.0/255.255.0.0</code><br /> + A network a.b.c.d, and a netmask w.x.y.z. For more + fine-grained subnet restriction. (Apache 1.3 and later)</dd> + + <dt>A network/nnn CIDR specification</dt> + + <dd>Example: <code>Allow from 10.1.0.0/16</code><br /> + Similar to the previous case, except the netmask consists of + nnn high-order 1 bits. (Apache 1.3 and later)</dd> + </dl> + + <p>Note that the last three examples above match exactly the + same set of hosts.</p> + + <p>The third format of the arguments to the <code>Allow</code> + directive allows access to the server to be controlled based on + the existence of an <a href="../env.html">environment + variable</a>. When <code>Allow from + env=</code><em>env-variable</em> is specified, then the request + is allowed access if the environment variable + <em>env-variable</em> exists. The server provides the ability + to set environment variables in a flexible way based on + characteristics of the client request using the directives + provided by <a href="mod_setenvif.html">mod_setenvif</a>. + Therefore, this directive can be used to allow access based on + such factors as the clients <code>User-Agent</code> (browser + type), <code>Referer</code>, or other HTTP request header + fields.</p> + + <p>Example:</p> + + <blockquote> +<pre> +SetEnvIf User-Agent ^KnockKnock/2\.0 let_me_in +<Directory /docroot> + Order Deny,Allow + Deny from all + Allow from env=let_me_in +</Directory> +</pre> + </blockquote> + + <p>In this case, browsers with a user-agent string beginning + with <tt>KnockKnock/2.0</tt> will be allowed access, and all + others will be denied.</p> + + <p>See also <a href="#deny">Deny</a>, <a + href="#order">Order</a> and <a + href="mod_setenvif.html#setenvif">SetEnvIf</a>.</p> + <hr /> + + <h2><a id="deny" name="deny">Deny</a> <a id="denyfromenv" + name="denyfromenv">directive</a></h2> + + <p> + <a href="directive-dict.html#Syntax" + rel="Help"><strong>Syntax:</strong></a> Deny from + all|<em>host</em>|env=<em>env-variable</em> + [<em>host</em>|env=<em>env-variable</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> Limit<br /> + <a href="directive-dict.html#Status" + rel="Help"><strong>Status:</strong></a> Base<br /> + <a href="directive-dict.html#Module" + rel="Help"><strong>Module:</strong></a> mod_access</p> + + <p>This directive allows access to the server to be restricted + based on hostname, IP address, or environment variables. The + arguments for the <code>Deny</code> directive are identical to + the arguments for the <a href="#allow">Allow</a> directive.</p> + + <p>See also <a href="#allow">Allow</a>, <a + href="#order">Order</a> and <a + href="mod_setenvif.html#setenvif">SetEnvIf</a>.</p> + <hr /> + + <h2><a id="order" name="order">Order directive</a></h2> + + <p> + <a href="directive-dict.html#Syntax" + rel="Help"><strong>Syntax:</strong></a> Order + <em>ordering</em><br /> + <a href="directive-dict.html#Default" + rel="Help"><strong>Default:</strong></a> <code>Order + Deny,Allow</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> Limit<br /> + <a href="directive-dict.html#Status" + rel="Help"><strong>Status:</strong></a> Base<br /> + <a href="directive-dict.html#Module" + rel="Help"><strong>Module:</strong></a> mod_access</p> + + <p>The <code>Order</code> directive, along with the + <code>Allow</code> and <code>Deny</code> directives, controls a + three-pass access control system. The first pass processes either + all <code>Allow</code> or all <code>Deny</code> directives, as + specified by the <code>Order</code> directive. The second pass + parses the rest of the directives (<code>Deny</code> or + <code>Allow</code>). The third pass applies to all requests which do + not match either of the first two.</p> + + <p>Note that all <code>Allow</code> and <code>Deny</code> directives + are processed, unlike a typical firewall, where only the first match + is used. The last match is effective (also unlike a typical + firewall). Additionally, the order in which lines appear in the + configuration files is not significant -- all <code>Allow</code> + lines are processed as one group, all <code>Deny</code> lines are + considered as another, and the default state is considered by + itself.</p> + + <p><em>Ordering</em> is one of:</p> + + <dl> + <dt><code>Allow,Deny</code></dt> + + <dd>First, all <code>Allow</code> directives are evaluated; at + least one must match, or the request is rejected. Next, all + <code>Deny</code> directives are evaluated. If any matches, the + request is rejected. Last, any requests which do not match an + <code>Allow</code> or a <code>Deny</code> directive are denied by + default.</dd> + + <dt><code>Deny,Allow</code></dt> + + <dd>First, all <code>Deny</code> directives are evaluated; if any + match, the request is denied <strong>unless</strong> it also + matches an <code>Allow</code> directive. Any requests which do not + match any <code>Allow</code> or <code>Deny</code> directives are + permitted.</dd> + + <dt><code>Mutual-failure</code></dt> + + <dd>This order has the same effect as <code>Order + Allow,Deny</code> and is deprecated in its favor.</dd> + </dl> + + <p>Keywords may only be separated by a comma; no whitespace is + allowed between them.</p> + + <table border="1"> + <tr> + <th>Match</th> + <th>Allow,Deny result</th> + <th>Deny,Allow result</th> + </tr><tr> + <th>Match Allow only</th> + <td>Request allowed</td> + <td>Request allowed</td> + </tr><tr> + <th>Match Deny only</th> + <td>Request denied</td> + <td>Request denied</td> + </tr><tr> + <th>No match</th> + <td>Default to second directive: Denied</td> + <td>Default to second directive: Allowed</td> + </tr><tr> + <th>Match both Allow & Deny</th> + <td>Final match controls: Denied</td> + <td>Final match controls: Allowed</td> + </tr> + </table> + + <p>In the following example, all hosts in the apache.org domain + are allowed access; all other hosts are denied access.</p> + + <blockquote> + <code>Order Deny,Allow<br /> + Deny from all<br /> + Allow from apache.org<br /> + </code> + </blockquote> + + <p>In the next example, all hosts in the apache.org domain are + allowed access, except for the hosts which are in the + foo.apache.org subdomain, who are denied access. All hosts not + in the apache.org domain are denied access because the default + state is to <code>Deny</code> access to the server.</p> + + <blockquote> + <code>Order Allow,Deny<br /> + Allow from apache.org<br /> + Deny from foo.apache.org<br /> + </code> + </blockquote> + + <p>On the other hand, if the <code>Order</code> in the last + example is changed to <code>Deny,Allow</code>, all hosts will + be allowed access. This happens because, regardless of the + actual ordering of the directives in the configuration file, + the <code>Allow from apache.org</code> will be evaluated last + and will override the <code>Deny from foo.apache.org</code>. + All hosts not in the <code>apache.org</code> domain will also + be allowed access because the default state is + <code>Allow</code>.</p> + + <p>The presence of an <code>Order</code> directive can affect + access to a part of the server even in the absence of + accompanying <code>Allow</code> and <code>Deny</code> + directives because of its effect on the default access state. + For example,</p> + + <blockquote> + <code><Directory /www><br /> + Order Allow,Deny<br /> + </Directory></code> + </blockquote> + + <p>will Deny all access to the <code>/www</code> directory + because the default access state is set to + <code>Deny</code>.</p> + + <p>The <code>Order</code> directive controls the order of + access directive processing only within each phase of the + server's configuration processing. This implies, for example, + that an <code>Allow</code> or <code>Deny</code> directive + occurring in a <Location> section will always be + evaluated after an <code>Allow</code> or <code>Deny</code> + directive occurring in a <Directory> section or + <code>.htaccess</code> file, regardless of the setting of the + <code>Order</code> directive. For details on the merging of + configuration sections, see the documentation on <a + href="../sections.html">How Directory, Location and Files + sections work</a>.</p> + + <p>See also: <a href="#deny">Deny</a> and <a + href="#allow">Allow</a>. <!--#include virtual="footer.html" --> + </p> + </body> +</html> + |