mirror of
https://github.com/apache/httpd.git
synced 2025-04-18 22:24:07 +03:00
01055edef2
git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1907148 13f79535-47bb-0310-9956-ffa450edef68
749 lines
42 KiB
XML
749 lines
42 KiB
XML
<?xml version="1.0" encoding="UTF-8"?>
|
|
<!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>
|
|
<meta content="text/html; charset=UTF-8" http-equiv="Content-Type" />
|
|
<!--
|
|
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
|
|
This file is generated from xml source: DO NOT EDIT
|
|
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
|
|
-->
|
|
<title>Expressions in Apache HTTP Server - Apache HTTP Server Version 2.5</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 rel="stylesheet" type="text/css" href="./style/css/prettify.css" />
|
|
<script src="./style/scripts/prettify.min.js" type="text/javascript">
|
|
</script>
|
|
|
|
<link href="./images/favicon.ico" rel="shortcut icon" /></head>
|
|
<body id="manual-page"><div id="page-header">
|
|
<p class="menu"><a href="./mod/">Modules</a> | <a href="./mod/quickreference.html">Directives</a> | <a href="http://wiki.apache.org/httpd/FAQ">FAQ</a> | <a href="./glossary.html">Glossary</a> | <a href="./sitemap.html">Sitemap</a></p>
|
|
<p class="apache">Apache HTTP Server Version 2.5</p>
|
|
<img alt="" src="./images/feather.png" /></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/">Documentation</a> > <a href="./">Version 2.5</a></div><div id="page-content"><div id="preamble"><h1>Expressions in Apache HTTP Server</h1>
|
|
<div class="toplang">
|
|
<p><span>Available Languages: </span><a href="./en/expr.html" title="English"> en </a> |
|
|
<a href="./fr/expr.html" hreflang="fr" rel="alternate" title="Français"> fr </a></p>
|
|
</div>
|
|
|
|
<p>Historically, there are several syntax variants for expressions
|
|
used to express a condition in the different modules of the Apache
|
|
HTTP Server. There is some ongoing effort to only use a single
|
|
variant, called <em>ap_expr</em>, for all configuration directives.
|
|
This document describes the <em>ap_expr</em> expression parser.
|
|
</p>
|
|
<p>The <em>ap_expr</em> expression is intended to replace most other
|
|
expression variants in HTTPD. For example, the deprecated <code class="directive"><a href="./mod/mod_ssl.html#sslrequire">SSLRequire</a></code> expressions can be replaced
|
|
by <a href="mod/mod_authz_core.html#reqexpr">Require expr</a>. </p>
|
|
</div>
|
|
<div id="quickview"><ul id="toc"><li><img alt="" src="./images/down.gif" /> <a href="#grammar">Grammar in Backus-Naur Form notation</a></li>
|
|
<li><img alt="" src="./images/down.gif" /> <a href="#vars">Variables</a></li>
|
|
<li><img alt="" src="./images/down.gif" /> <a href="#binop">Binary operators</a></li>
|
|
<li><img alt="" src="./images/down.gif" /> <a href="#unnop">Unary operators</a></li>
|
|
<li><img alt="" src="./images/down.gif" /> <a href="#functions">Functions</a></li>
|
|
<li><img alt="" src="./images/down.gif" /> <a href="#other">Other</a></li>
|
|
<li><img alt="" src="./images/down.gif" /> <a href="#sslrequire">Comparison with SSLRequire</a></li>
|
|
<li><img alt="" src="./images/down.gif" /> <a href="#compatibility">Version History</a></li>
|
|
<li><img alt="" src="./images/down.gif" /> <a href="#examples">Example expressions</a></li>
|
|
</ul><h3>See also</h3><ul class="seealso"><li><code class="directive"><a href="./mod/core.html#if"><If></a></code></li><li><code class="directive"><a href="./mod/core.html#elseif"><ElseIf></a></code></li><li><code class="directive"><a href="./mod/core.html#else"><Else></a></code></li><li><code class="directive"><a href="./mod/core.html#errordocument">ErrorDocument</a></code></li><li><code class="directive"><a href="./mod/mod_alias.html#alias">Alias</a></code></li><li><code class="directive"><a href="./mod/mod_alias.html#scriptalias">ScriptAlias</a></code></li><li><code class="directive"><a href="./mod/mod_alias.html#redirect">Redirect</a></code></li><li><code class="directive"><a href="./mod/mod_auth_basic.html#authbasicfake">AuthBasicFake</a></code></li><li><code class="directive"><a href="./mod/mod_auth_form.html#authformloginrequiredlocation">AuthFormLoginRequiredLocation</a></code></li><li><code class="directive"><a href="./mod/mod_auth_form.html#authformloginsuccesslocation">AuthFormLoginSuccessLocation</a></code></li><li><code class="directive"><a href="./mod/mod_auth_form.html#authformlogoutlocation">AuthFormLogoutLocation</a></code></li><li><code class="directive"><a href="./mod/mod_authn_core.html#authname">AuthName</a></code></li><li><code class="directive"><a href="./mod/mod_authn_core.html#authtype">AuthType</a></code></li><li><code class="directive"><a href="./mod/mod_rewrite.html#rewritecond">RewriteCond</a></code></li><li><code class="directive"><a href="./mod/mod_setenvif.html#setenvifexpr">SetEnvIfExpr</a></code></li><li><code class="directive"><a href="./mod/mod_headers.html#header">Header</a></code></li><li><code class="directive"><a href="./mod/mod_headers.html#requestheader">RequestHeader</a></code></li><li><code class="directive"><a href="./mod/mod_filter.html#filterprovider">FilterProvider</a></code></li><li><code class="directive"><a href="./mod/mod_crypto.html#cryptokey">CryptoKey</a></code></li><li><code class="directive"><a href="./mod/mod_crypto.html#cryptoiv">CryptoIV</a></code></li><li><a href="mod/mod_authz_core.html#reqexpr">Require expr</a></li><li><a href="mod/mod_authnz_ldap.html#requser">Require ldap-user</a></li><li><a href="mod/mod_authnz_ldap.html#reqgroup">Require ldap-group</a></li><li><a href="mod/mod_authnz_ldap.html#reqdn">Require ldap-dn</a></li><li><a href="mod/mod_authnz_ldap.html#reqattribute">Require ldap-attribute</a></li><li><a href="mod/mod_authnz_ldap.html#reqfilter">Require ldap-filter</a></li><li><a href="mod/mod_authnz_ldap.html#reqsearch">Require ldap-search</a></li><li><a href="mod/mod_authz_dbd.html#reqgroup">Require dbd-group</a></li><li><a href="mod/mod_authz_dbm.html#reqgroup">Require dbm-group</a></li><li><a href="mod/mod_authz_groupfile.html#reqgroup">Require group</a></li><li><a href="mod/mod_authz_host.html#reqhost">Require host</a></li><li><code class="directive"><a href="./mod/mod_ssl.html#sslrequire">SSLRequire</a></code></li><li><code class="directive"><a href="./mod/mod_log_debug.html#logmessage">LogMessage</a></code></li><li><code class="module"><a href="./mod/mod_include.html">mod_include</a></code></li><li><a href="#comments_section">Comments</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="grammar" id="grammar">Grammar in Backus-Naur Form notation</a> <a title="Permanent link" href="#grammar" class="permalink">¶</a></h2>
|
|
|
|
<p><a href="http://en.wikipedia.org/wiki/Backus%E2%80%93Naur_Form">Backus-Naur
|
|
Form</a> (BNF) is a notation technique for context-free grammars,
|
|
often used to describe the syntax of languages used in computing.
|
|
In most cases, expressions are used to express boolean values.
|
|
For these, the starting point in the BNF is <code>cond</code>.
|
|
Directives like <code class="directive"><a href="./mod/core.html#errordocument">ErrorDocument</a></code>,
|
|
<code class="directive"><a href="./mod/mod_authz_core.html#require">Require</a></code>,
|
|
<code class="directive"><a href="./mod/mod_authn_core.html#authname">AuthName</a></code>,
|
|
<code class="directive"><a href="./mod/mod_alias.html#redirect">Redirect</a></code>,
|
|
<code class="directive"><a href="./mod/mod_headers.html#header">Header</a></code>,
|
|
<code class="directive"><a href="./mod/mod_crypto.html#cryptokey">CryptoKey</a></code> or
|
|
<code class="directive"><a href="./mod/mod_log_debug.html#logmessage">LogMessage</a></code> accept expressions
|
|
that evaluate to a string value. For those, the starting point in
|
|
the BNF is <code>string</code>.
|
|
</p>
|
|
<blockquote>
|
|
<pre>expr ::= cond
|
|
| string
|
|
|
|
string ::= substring
|
|
| string substring
|
|
|
|
cond ::= "<strong>true</strong>"
|
|
| "<strong>false</strong>"
|
|
| "<strong>!</strong>" cond
|
|
| cond "<strong>&&</strong>" cond
|
|
| cond "<strong>||</strong>" cond
|
|
| comp
|
|
| "<strong>(</strong>" cond "<strong>)</strong>"
|
|
|
|
comp ::= stringcomp
|
|
| integercomp
|
|
| unaryop word
|
|
| word binaryop word
|
|
| word "<strong>in</strong>" listfunc
|
|
| word "<strong>=~</strong>" regex
|
|
| word "<strong>!~</strong>" regex
|
|
| word "<strong>in</strong>" "<strong>{</strong>" list "<strong>}</strong>"
|
|
|
|
|
|
stringcomp ::= word "<strong>==</strong>" word
|
|
| word "<strong>!=</strong>" word
|
|
| word "<strong><</strong>" word
|
|
| word "<strong><=</strong>" word
|
|
| word "<strong>></strong>" word
|
|
| word "<strong>>=</strong>" word
|
|
|
|
integercomp ::= word "<strong>-eq</strong>" word | word "<strong>eq</strong>" word
|
|
| word "<strong>-ne</strong>" word | word "<strong>ne</strong>" word
|
|
| word "<strong>-lt</strong>" word | word "<strong>lt</strong>" word
|
|
| word "<strong>-le</strong>" word | word "<strong>le</strong>" word
|
|
| word "<strong>-gt</strong>" word | word "<strong>gt</strong>" word
|
|
| word "<strong>-ge</strong>" word | word "<strong>ge</strong>" word
|
|
|
|
word ::= digits
|
|
| "<strong>'</strong>" string "<strong>'</strong>"
|
|
| '<strong>"</strong>' string '<strong>"</strong>'
|
|
| word "<strong>.</strong>" word
|
|
| variable
|
|
| sub
|
|
| join
|
|
| function
|
|
| "<strong>(</strong>" word "<strong>)</strong>"
|
|
|
|
list ::= split
|
|
| listfunc
|
|
| "<strong>{</strong>" words "<strong>}</strong>"
|
|
| "<strong>(</strong>" list "<strong>)</strong>"
|
|
|
|
substring ::= cstring
|
|
| variable
|
|
|
|
variable ::= "<strong>%{</strong>" varname "<strong>}</strong>"
|
|
| "<strong>%{</strong>" funcname "<strong>:</strong>" funcargs "<strong>}</strong>"
|
|
| "<strong>%{:</strong>" word "<strong>:}</strong>"
|
|
| "<strong>%{:</strong>" cond "<strong>:}</strong>"
|
|
| rebackref
|
|
|
|
sub ::= "<strong>sub</strong>" ["<strong>(</strong>"] regsub "<strong>,</strong>" word ["<strong>)</strong>"]
|
|
|
|
join ::= "<strong>join</strong>" ["<strong>(</strong>"] list ["<strong>)</strong>"]
|
|
| "<strong>join</strong>" ["<strong>(</strong>"] list "<strong>,</strong>" word ["<strong>)</strong>"]
|
|
|
|
split ::= "<strong>split</strong>" ["<strong>(</strong>"] regany "<strong>,</strong>" list ["<strong>)</strong>"]
|
|
| "<strong>split</strong>" ["<strong>(</strong>"] regany "<strong>,</strong>" word ["<strong>)</strong>"]
|
|
|
|
function ::= funcname "<strong>(</strong>" words "<strong>)</strong>"
|
|
|
|
listfunc ::= listfuncname "<strong>(</strong>" words "<strong>)</strong>"
|
|
|
|
words ::= word
|
|
| word "<strong>,</strong>" list
|
|
|
|
regex ::= "<strong>/</strong>" regpattern "<strong>/</strong>" [regflags]
|
|
| "<strong>m</strong>" regsep regpattern regsep [regflags]
|
|
|
|
regsub ::= "<strong>s</strong>" regsep regpattern regsep string regsep [regflags]
|
|
|
|
regany ::= regex | regsub
|
|
|
|
regsep ::= "/" | "#" | "$" | "%" | "^" | "|" | "?" | "!" | "'" | '"' | "," | ";" | ":" | "." | "_" | "-"
|
|
|
|
regflags ::= 1*("i" | "s" | "m" | "g")
|
|
regpattern ::= cstring ; except enclosing <em>regsep</em>
|
|
|
|
rebackref ::= "<strong>$</strong>" DIGIT
|
|
|
|
digits ::= 1*(DIGIT)
|
|
cstring ::= 0*(TEXT)
|
|
|
|
TEXT ::= <any OCTET except CTLs>
|
|
DIGIT ::= <any US-ASCII digit "0".."9"></pre>
|
|
</blockquote>
|
|
|
|
</div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div>
|
|
<div class="section">
|
|
<h2><a name="vars" id="vars">Variables</a> <a title="Permanent link" href="#vars" class="permalink">¶</a></h2>
|
|
|
|
|
|
<p>The expression parser provides a number of variables of the form
|
|
<code>%{HTTP_HOST}</code>. Note that the value of a variable may depend
|
|
on the phase of the request processing in which it is evaluated. For
|
|
example, an expression used in an <code class="directive"><If ></code>
|
|
directive is evaluated before authentication is done. Therefore,
|
|
<code>%{REMOTE_USER}</code> will not be set in this case.</p>
|
|
|
|
<p>The following variables provide the values of the named HTTP request
|
|
headers. The values of other headers can be obtained with the
|
|
<code>req</code> <a href="#functions">function</a>. Using these
|
|
variables may cause the header name to be added to the Vary
|
|
header of the HTTP response, except where otherwise noted for the
|
|
directive accepting the expression. The <code>req_novary</code>
|
|
<a href="#functions">function</a> may be used to circumvent this
|
|
behavior.</p>
|
|
|
|
<table class="bordered"><tr class="header"><th>Name</th></tr>
|
|
<tr><td><code>HTTP_ACCEPT</code></td></tr>
|
|
<tr class="odd"><td><code>HTTP_COOKIE</code></td></tr>
|
|
<tr><td><code>HTTP_FORWARDED</code></td></tr>
|
|
<tr class="odd"><td><code>HTTP_HOST</code></td></tr>
|
|
<tr><td><code>HTTP_PROXY_CONNECTION</code></td></tr>
|
|
<tr class="odd"><td><code>HTTP_REFERER</code></td></tr>
|
|
<tr><td><code>HTTP_USER_AGENT</code></td></tr>
|
|
</table>
|
|
|
|
<p>Other request related variables</p>
|
|
|
|
<table class="bordered"><tr class="header"><th>Name</th><th>Description</th></tr>
|
|
<tr><td><code>REQUEST_METHOD</code></td>
|
|
<td>The HTTP method of the incoming request (e.g.
|
|
<code>GET</code>)</td></tr>
|
|
<tr class="odd"><td><code>REQUEST_SCHEME</code></td>
|
|
<td>The scheme part of the request's URI</td></tr>
|
|
<tr><td><code>REQUEST_URI</code></td>
|
|
<td>The path part of the request's URI</td></tr>
|
|
<tr class="odd"><td><code>DOCUMENT_URI</code></td>
|
|
<td>Same as <code>REQUEST_URI</code></td></tr>
|
|
<tr><td><code>REQUEST_FILENAME</code></td>
|
|
<td>The full local filesystem path to the file or script matching the
|
|
request, if this has already been determined by the server at the
|
|
time <code>REQUEST_FILENAME</code> is referenced. Otherwise, such
|
|
as when used in virtual host context, the same value as
|
|
<code>REQUEST_URI</code> </td></tr>
|
|
<tr class="odd"><td><code>SCRIPT_FILENAME</code></td>
|
|
<td>Same as <code>REQUEST_FILENAME</code></td></tr>
|
|
<tr><td><code>LAST_MODIFIED</code></td>
|
|
<td>The date and time of last modification of the file in the format
|
|
<code>20101231235959</code>, if this has already been determined by
|
|
the server at the time <code>LAST_MODIFIED</code> is referenced.
|
|
</td></tr>
|
|
<tr class="odd"><td><code>SCRIPT_USER</code></td>
|
|
<td>The user name of the owner of the script.</td></tr>
|
|
<tr><td><code>SCRIPT_GROUP</code></td>
|
|
<td>The group name of the group of the script.</td></tr>
|
|
<tr class="odd"><td><code>PATH_INFO</code></td>
|
|
<td>The trailing path name information, see
|
|
<code class="directive"><a href="./mod/core.html#acceptpathinfo">AcceptPathInfo</a></code></td></tr>
|
|
<tr><td><code>QUERY_STRING</code></td>
|
|
<td>The query string of the current request</td></tr>
|
|
<tr class="odd"><td><code>IS_SUBREQ</code></td>
|
|
<td>"<code>true</code>" if the current request is a subrequest,
|
|
"<code>false</code>" otherwise</td></tr>
|
|
<tr><td><code>THE_REQUEST</code></td>
|
|
<td>The complete request line (e.g.,
|
|
"<code>GET /index.html HTTP/1.1</code>")</td></tr>
|
|
<tr class="odd"><td><code>REMOTE_ADDR</code></td>
|
|
<td>The IP address of the remote host</td></tr>
|
|
<tr><td><code>REMOTE_PORT</code></td>
|
|
<td>The port of the remote host (2.4.26 and later)</td></tr>
|
|
<tr class="odd"><td><code>REMOTE_HOST</code></td>
|
|
<td>The host name of the remote host</td></tr>
|
|
<tr><td><code>REMOTE_USER</code></td>
|
|
<td>The name of the authenticated user, if any (not available during <code class="directive"><If></code>)</td></tr>
|
|
<tr class="odd"><td><code>REMOTE_IDENT</code></td>
|
|
<td>The user name set by <code class="module"><a href="./mod/mod_ident.html">mod_ident</a></code></td></tr>
|
|
<tr><td><code>SERVER_NAME</code></td>
|
|
<td>The <code class="directive"><a href="./mod/core.html#servername">ServerName</a></code> of
|
|
the current vhost</td></tr>
|
|
<tr class="odd"><td><code>SERVER_PORT</code></td>
|
|
<td>The server port of the current vhost, see
|
|
<code class="directive"><a href="./mod/core.html#servername">ServerName</a></code></td></tr>
|
|
<tr><td><code>SERVER_ADMIN</code></td>
|
|
<td>The <code class="directive"><a href="./mod/core.html#serveradmin">ServerAdmin</a></code> of
|
|
the current vhost</td></tr>
|
|
<tr class="odd"><td><code>SERVER_PROTOCOL</code></td>
|
|
<td>The protocol used by the request (e.g. HTTP/1.1). In some types of
|
|
internal subrequests, this variable has the value
|
|
<code>INCLUDED</code>.</td></tr>
|
|
<tr><td><code>SERVER_PROTOCOL_VERSION</code></td>
|
|
<td>A number that encodes the HTTP version of the request:
|
|
<code>1000 * major + minor</code>. For example, <code>1001</code>
|
|
corresponds to HTTP/1.1 and <code>9</code> corresponds
|
|
to HTTP/0.9</td></tr>
|
|
<tr class="odd"><td><code>SERVER_PROTOCOL_VERSION_MAJOR</code></td>
|
|
<td>The major version part of the HTTP version of the request,
|
|
e.g. <code>1</code> for HTTP/1.0</td></tr>
|
|
<tr><td><code>SERVER_PROTOCOL_VERSION_MINOR</code></td>
|
|
<td>The minor version part of the HTTP version of the request,
|
|
e.g. <code>0</code> for HTTP/1.0</td></tr>
|
|
<tr class="odd"><td><code>DOCUMENT_ROOT</code></td>
|
|
<td>The <code class="directive"><a href="./mod/core.html#documentroot">DocumentRoot</a></code> of
|
|
the current vhost</td></tr>
|
|
<tr><td><code>AUTH_TYPE</code></td>
|
|
<td>The configured <code class="directive"><a href="./mod/mod_authn_core.html#authtype">AuthType</a></code> (e.g.
|
|
"<code>basic</code>")</td></tr>
|
|
<tr class="odd"><td><code>CONTENT_TYPE</code></td>
|
|
<td>The content type of the response (not available during <code class="directive"><If></code>)</td></tr>
|
|
<tr><td><code>HANDLER</code></td>
|
|
<td>The name of the <a href="handler.html">handler</a> creating
|
|
the response</td></tr>
|
|
<tr class="odd"><td><code>HTTP2</code></td>
|
|
<td>"<code>on</code>" if the request uses http/2,
|
|
"<code>off</code>" otherwise</td></tr>
|
|
<tr><td><code>HTTPS</code></td>
|
|
<td>"<code>on</code>" if the request uses https,
|
|
"<code>off</code>" otherwise</td></tr>
|
|
<tr class="odd"><td><code>IPV6</code></td>
|
|
<td>"<code>on</code>" if the connection uses IPv6,
|
|
"<code>off</code>" otherwise</td></tr>
|
|
<tr><td><code>REQUEST_STATUS</code></td>
|
|
<td>The HTTP error status of the request (not available during <code class="directive"><If></code>)</td></tr>
|
|
<tr class="odd"><td><code>REQUEST_LOG_ID</code></td>
|
|
<td>The error log id of the request (see
|
|
<code class="directive"><a href="./mod/core.html#errorlogformat">ErrorLogFormat</a></code>)</td></tr>
|
|
<tr><td><code>CONN_LOG_ID</code></td>
|
|
<td>The error log id of the connection (see
|
|
<code class="directive"><a href="./mod/core.html#errorlogformat">ErrorLogFormat</a></code>)</td></tr>
|
|
<tr class="odd"><td><code>CONN_REMOTE_ADDR</code></td>
|
|
<td>The peer IP address of the connection (see the
|
|
<code class="module"><a href="./mod/mod_remoteip.html">mod_remoteip</a></code> module)</td></tr>
|
|
<tr><td><code>CONTEXT_PREFIX</code></td>
|
|
<td /></tr>
|
|
<tr class="odd"><td><code>CONTEXT_DOCUMENT_ROOT</code></td>
|
|
<td /></tr>
|
|
</table>
|
|
|
|
<p>Misc variables</p>
|
|
|
|
<table class="bordered"><tr class="header"><th>Name</th><th>Description</th></tr>
|
|
<tr><td><code>TIME_YEAR</code></td>
|
|
<td>The current year (e.g. <code>2010</code>)</td></tr>
|
|
<tr class="odd"><td><code>TIME_MON</code></td>
|
|
<td>The current month (<code>01</code>, ..., <code>12</code>)</td></tr>
|
|
<tr><td><code>TIME_DAY</code></td>
|
|
<td>The current day of the month (<code>01</code>, ...)</td></tr>
|
|
<tr class="odd"><td><code>TIME_HOUR</code></td>
|
|
<td>The hour part of the current time
|
|
(<code>00</code>, ..., <code>23</code>)</td></tr>
|
|
<tr><td><code>TIME_MIN</code></td>
|
|
<td>The minute part of the current time </td></tr>
|
|
<tr class="odd"><td><code>TIME_SEC</code></td>
|
|
<td>The second part of the current time </td></tr>
|
|
<tr><td><code>TIME_WDAY</code></td>
|
|
<td>The day of the week (starting with <code>0</code>
|
|
for Sunday)</td></tr>
|
|
<tr class="odd"><td><code>TIME</code></td>
|
|
<td>The date and time in the format
|
|
<code>20101231235959</code></td></tr>
|
|
<tr><td><code>SERVER_SOFTWARE</code></td>
|
|
<td>The server version string</td></tr>
|
|
<tr class="odd"><td><code>API_VERSION</code></td>
|
|
<td>The date of the API version (module magic number)</td></tr>
|
|
</table>
|
|
|
|
<p>Some modules register additional variables, see e.g.
|
|
<code class="module"><a href="./mod/mod_ssl.html">mod_ssl</a></code>.</p>
|
|
|
|
<p>Any variable can be embedded in a <em>string</em>, both in quoted
|
|
strings from boolean expressions but also in string expressions,
|
|
resulting in the concatenation of the constant and dynamic parts as
|
|
expected.</p>
|
|
|
|
<p>There exists another form of variables (temporaries) expressed like
|
|
<code>%{:<em>word</em>:}</code> and which allow embedding of the more
|
|
powerful <em>word</em> syntax (and constructs) in both type of expressions,
|
|
without colliding with the constant part of such strings. They are mainly
|
|
useful in string expressions though, since the <em>word</em> is directly
|
|
available in boolean expressions already. By using this form of variables,
|
|
one can evaluate regexes, substitutions, join and/or split strings and
|
|
lists in the scope of string expressions, hence construct complex strings
|
|
dynamically.</p>
|
|
|
|
</div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div>
|
|
<div class="section">
|
|
<h2><a name="binop" id="binop">Binary operators</a> <a title="Permanent link" href="#binop" class="permalink">¶</a></h2>
|
|
|
|
|
|
<p>With the exception of some built-in comparison operators, binary
|
|
operators have the form "<code>-[a-zA-Z][a-zA-Z0-9_]+</code>", i.e. a
|
|
minus and at least two characters. The name is not case sensitive.
|
|
Modules may register additional binary operators.</p>
|
|
|
|
<h3><a name="comp" id="comp">Comparison operators</a></h3>
|
|
|
|
|
|
<table class="bordered"><tr class="header"><th>Name</th><th>Alternative</th> <th>Description</th></tr>
|
|
<tr><td><code>==</code></td>
|
|
<td><code>=</code></td>
|
|
<td>String equality</td></tr>
|
|
<tr class="odd"><td><code>!=</code></td>
|
|
<td />
|
|
<td>String inequality</td></tr>
|
|
<tr><td><code><</code></td>
|
|
<td />
|
|
<td>String less than</td></tr>
|
|
<tr class="odd"><td><code><=</code></td>
|
|
<td />
|
|
<td>String less than or equal</td></tr>
|
|
<tr><td><code>></code></td>
|
|
<td />
|
|
<td>String greater than</td></tr>
|
|
<tr class="odd"><td><code>>=</code></td>
|
|
<td />
|
|
<td>String greater than or equal</td></tr>
|
|
<tr><td><code>=~</code></td>
|
|
<td />
|
|
<td>String matches the regular expression</td></tr>
|
|
<tr class="odd"><td><code>!~</code></td>
|
|
<td />
|
|
<td>String does not match the regular expression</td></tr>
|
|
<tr><td><code>-eq</code></td>
|
|
<td><code>eq</code></td>
|
|
<td>Integer equality</td></tr>
|
|
<tr class="odd"><td><code>-ne</code></td>
|
|
<td><code>ne</code></td>
|
|
<td>Integer inequality</td></tr>
|
|
<tr><td><code>-lt</code></td>
|
|
<td><code>lt</code></td>
|
|
<td>Integer less than</td></tr>
|
|
<tr class="odd"><td><code>-le</code></td>
|
|
<td><code>le</code></td>
|
|
<td>Integer less than or equal</td></tr>
|
|
<tr><td><code>-gt</code></td>
|
|
<td><code>gt</code></td>
|
|
<td>Integer greater than</td></tr>
|
|
<tr class="odd"><td><code>-ge</code></td>
|
|
<td><code>ge</code></td>
|
|
<td>Integer greater than or equal</td></tr>
|
|
</table>
|
|
|
|
|
|
<h3><a name="binaryother" id="binaryother">Other binary operators</a></h3>
|
|
|
|
|
|
<table class="bordered"><tr class="header"><th>Name</th><th>Description</th></tr>
|
|
<tr><td><code>-ipmatch</code></td>
|
|
<td>IP address matches address/netmask</td></tr>
|
|
<tr class="odd"><td><code>-strmatch</code></td>
|
|
<td>left string matches pattern given by right string (containing
|
|
wildcards *, ?, [])</td></tr>
|
|
<tr><td><code>-strcmatch</code></td>
|
|
<td>same as <code>-strmatch</code>, but case insensitive</td></tr>
|
|
<tr class="odd"><td><code>-fnmatch</code></td>
|
|
<td>same as <code>-strmatch</code>, but slashes are not matched by
|
|
wildcards</td></tr>
|
|
</table>
|
|
|
|
|
|
</div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div>
|
|
<div class="section">
|
|
<h2><a name="unnop" id="unnop">Unary operators</a> <a title="Permanent link" href="#unnop" class="permalink">¶</a></h2>
|
|
|
|
|
|
<p>Unary operators take one argument and have the form
|
|
"<code>-[a-zA-Z]</code>", i.e. a minus and one character.
|
|
The name <em>is</em> case sensitive.
|
|
Modules may register additional unary operators.</p>
|
|
|
|
<table class="bordered"><tr class="header"><th>Name</th><th>Description</th><th>Restricted</th></tr>
|
|
<tr><td><code>-d</code></td>
|
|
<td>The argument is treated as a filename.
|
|
True if the file exists and is a directory</td><td>yes</td></tr>
|
|
<tr class="odd"><td><code>-e</code></td>
|
|
<td>The argument is treated as a filename.
|
|
True if the file (or dir or special) exists</td><td>yes</td></tr>
|
|
<tr><td><code>-f</code></td>
|
|
<td>The argument is treated as a filename.
|
|
True if the file exists and is regular file</td><td>yes</td></tr>
|
|
<tr class="odd"><td><code>-s</code></td>
|
|
<td>The argument is treated as a filename.
|
|
True if the file exists and is not empty</td><td>yes</td></tr>
|
|
<tr><td><code>-L</code></td>
|
|
<td>The argument is treated as a filename.
|
|
True if the file exists and is symlink</td><td>yes</td></tr>
|
|
<tr class="odd"><td><code>-h</code></td>
|
|
<td>The argument is treated as a filename.
|
|
True if the file exists and is symlink
|
|
(same as <code>-L</code>)</td><td>yes</td></tr>
|
|
<tr><td><code>-F</code></td>
|
|
<td>True if string is a valid file, accessible via all the server's
|
|
currently-configured access controls for that path. This uses an
|
|
internal subrequest to do the check, so use it with care - it can
|
|
impact your server's performance!</td><td /></tr>
|
|
<tr class="odd"><td><code>-U</code></td>
|
|
<td>True if string is a valid URL, accessible via all the server's
|
|
currently-configured access controls for that path. This uses an
|
|
internal subrequest to do the check, so use it with care - it can
|
|
impact your server's performance!</td><td /></tr>
|
|
<tr><td><code>-A</code></td>
|
|
<td>Alias for <code>-U</code></td><td /></tr>
|
|
<tr class="odd"><td><code>-n</code></td>
|
|
<td>True if string is not empty</td><td /></tr>
|
|
<tr><td><code>-z</code></td>
|
|
<td>True if string is empty</td><td /></tr>
|
|
<tr class="odd"><td><code>-T</code></td>
|
|
<td>False if string is empty, "<code>0</code>", "<code>off</code>",
|
|
"<code>false</code>", or "<code>no</code>" (case insensitive).
|
|
True otherwise.</td><td /></tr>
|
|
<tr><td><code>-R</code></td>
|
|
<td>Same as "<code>%{REMOTE_ADDR} -ipmatch ...</code>", but more
|
|
efficient
|
|
</td><td /></tr>
|
|
</table>
|
|
|
|
<p>The operators marked as "restricted" are not available in some modules
|
|
like <code class="module"><a href="./mod/mod_include.html">mod_include</a></code>.</p>
|
|
</div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div>
|
|
<div class="section">
|
|
<h2><a name="functions" id="functions">Functions</a> <a title="Permanent link" href="#functions" class="permalink">¶</a></h2>
|
|
|
|
|
|
<p>Normal string-valued functions take one string as argument and return
|
|
a string. Functions names are not case sensitive.
|
|
Modules may register additional functions.</p>
|
|
|
|
<table class="bordered"><tr class="header"><th>Name</th><th>Description</th><th>Special notes</th></tr>
|
|
<tr><td><code>req</code>, <code>http</code></td>
|
|
<td>Get HTTP request header; header names may be added to the Vary
|
|
header, see below</td><td /></tr>
|
|
<tr class="odd"><td><code>req_novary</code></td>
|
|
<td>Same as <code>req</code>, but header names will not be added to the
|
|
Vary header</td><td /></tr>
|
|
<tr><td><code>resp</code></td>
|
|
<td>Get HTTP response header (most response headers will not yet be set
|
|
during <code class="directive"><If></code>)</td><td /></tr>
|
|
<tr class="odd"><td><code>reqenv</code></td>
|
|
<td>Lookup request environment variable (as a shortcut,
|
|
<code>v</code> can also be used to access variables).
|
|
</td>
|
|
<td>ordering</td></tr>
|
|
<tr><td><code>osenv</code></td>
|
|
<td>Lookup operating system environment variable</td><td /></tr>
|
|
<tr class="odd"><td><code>note</code></td>
|
|
<td>Lookup request note</td><td>ordering</td></tr>
|
|
<tr><td><code>env</code></td>
|
|
<td>Return first match of <code>note</code>, <code>reqenv</code>,
|
|
<code>osenv</code></td><td>ordering</td></tr>
|
|
<tr class="odd"><td><code>tolower</code></td>
|
|
<td>Convert string to lower case</td><td /></tr>
|
|
<tr><td><code>toupper</code></td>
|
|
<td>Convert string to upper case</td><td /></tr>
|
|
<tr class="odd"><td><code>escape</code></td>
|
|
<td>Escape special characters in %hex encoding</td><td /></tr>
|
|
<tr><td><code>unescape</code></td>
|
|
<td>Unescape %hex encoded string, leaving encoded slashes alone;
|
|
return empty string if %00 is found</td><td /></tr>
|
|
<tr class="odd"><td><code>base64</code></td>
|
|
<td>Encode the string using base64 encoding</td><td /></tr>
|
|
<tr><td><code>unbase64</code></td>
|
|
<td>Decode base64 encoded string, return truncated string if 0x00 is
|
|
found</td><td /></tr>
|
|
<tr class="odd"><td><code>md5</code></td>
|
|
<td>Hash the string using MD5, then encode the hash with hexadecimal
|
|
encoding</td><td /></tr>
|
|
<tr><td><code>sha1</code></td>
|
|
<td>Hash the string using SHA1, then encode the hash with hexadecimal
|
|
encoding</td><td /></tr>
|
|
<tr class="odd"><td><code>file</code></td>
|
|
<td>Read contents from a file (including line endings, when present)
|
|
</td><td>restricted</td></tr>
|
|
<tr><td><code>filemod</code></td>
|
|
<td>Return last modification time of a file (or 0 if file does not exist
|
|
or is not regular file)</td><td>restricted</td></tr>
|
|
<tr class="odd"><td><code>filesize</code></td>
|
|
<td>Return size of a file (or 0 if file does not exist or is not
|
|
regular file)</td><td>restricted</td></tr>
|
|
<tr><td><code>ldap</code></td>
|
|
<td>Escape characters as required by LDAP distinguished name escaping
|
|
(RFC4514) and LDAP filter escaping (RFC4515).<br />
|
|
(Available in httpd 2.4.53 and later)</td><td /></tr>
|
|
<tr class="odd"><td><code>replace</code></td>
|
|
<td>replace(string, "from", "to") replaces all occurrences of "from"
|
|
in the string with "to". The first parameter must not be a literal string.
|
|
</td><td /></tr>
|
|
</table>
|
|
|
|
<p>The functions marked as "restricted" in the final column are not
|
|
available in some modules like <code class="module"><a href="./mod/mod_include.html">mod_include</a></code>.</p>
|
|
|
|
<p>The functions marked as "ordering" in the final column require some
|
|
consideration for the ordering of different components of the server,
|
|
especially when the function is used within the
|
|
<<code class="directive"><a href="./mod/core.html#if">If</a></code>> directive which is
|
|
evaluated relatively early.</p>
|
|
<div class="note">
|
|
<h3>Environment variable ordering</h3>
|
|
When environment variables are looked up within an
|
|
<<code class="directive"><a href="./mod/core.html#if">If</a></code>> condition, it's important
|
|
to consider how extremely early in request processing that this
|
|
resolution occurs. As a guideline, any directive defined outside of virtual host
|
|
context (directory, location, htaccess) is not likely to have yet had a
|
|
chance to execute. <code class="directive"><a href="./mod/mod_setenvif.html#setenvif">SetEnvIf</a></code>
|
|
in virtual host scope is one directive that runs prior to this resolution
|
|
<br />
|
|
<br />
|
|
When <code>reqenv</code> is used outside of <<code class="directive"><a href="./mod/core.html#if">If</a></code>>, the resolution will generally occur later, but the
|
|
exact timing depends on the directive the expression has been used within.
|
|
</div>
|
|
|
|
<p>When the functions <code>req</code> or <code>http</code> are used,
|
|
the header name will automatically be added to the Vary header of the
|
|
HTTP response, except where otherwise noted for the directive accepting
|
|
the expression. The <code>req_novary</code> function can be used to
|
|
prevent names from being added to the Vary header.</p>
|
|
|
|
<p>In addition to string-valued functions, there are also
|
|
list-valued functions which take one string as argument and return a
|
|
list, i.e. a list of strings. The list can be used with the
|
|
special <code>-in</code> operator. Functions names are not case
|
|
sensitive. Modules may register additional functions.</p>
|
|
|
|
<p>There are no built-in list-valued functions. <code class="module"><a href="./mod/mod_ssl.html">mod_ssl</a></code>
|
|
provides <code>PeerExtList</code>. See the description of
|
|
<code class="directive"><a href="./mod/mod_ssl.html#sslrequire">SSLRequire</a></code> for details
|
|
(but <code>PeerExtList</code> is also usable outside
|
|
of <code class="directive"><a href="./mod/mod_ssl.html#sslrequire">SSLRequire</a></code>).</p>
|
|
|
|
</div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div>
|
|
<div class="section">
|
|
<h2><a name="other" id="other">Other</a> <a title="Permanent link" href="#other" class="permalink">¶</a></h2>
|
|
|
|
|
|
<table class="bordered"><tr class="header"><th>Name</th><th>Alternative</th> <th>Description</th></tr>
|
|
<tr><td><code>-in</code></td>
|
|
<td><code>in</code></td>
|
|
<td>string contained in list</td></tr>
|
|
<tr class="odd"><td><code>/regexp/</code></td>
|
|
<td><code>m#regexp#</code></td>
|
|
<td>Regular expression (the second form allows different
|
|
delimiters than /)</td></tr>
|
|
<tr><td><code>/regexp/i</code></td>
|
|
<td><code>m#regexp#i</code></td>
|
|
<td>Case insensitive regular expression</td></tr>
|
|
<tr class="odd"><td><code>$0 ... $9</code></td>
|
|
<td />
|
|
<td>Regular expression backreferences</td></tr>
|
|
</table>
|
|
|
|
<h3><a name="rebackref" id="rebackref">Regular expression backreferences</a></h3>
|
|
|
|
<p>The strings <code>$0</code> ... <code>$9</code> allow to reference
|
|
the capture groups from a previously executed, successfully
|
|
matching regular expressions. They can normally only be used in the
|
|
same expression as the matching regex, but some modules allow special
|
|
uses.</p>
|
|
|
|
|
|
</div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div>
|
|
<div class="section">
|
|
<h2><a name="sslrequire" id="sslrequire">Comparison with SSLRequire</a> <a title="Permanent link" href="#sslrequire" class="permalink">¶</a></h2>
|
|
|
|
<p>The <em>ap_expr</em> syntax is mostly a superset of the syntax of the
|
|
deprecated <code class="directive"><a href="./mod/mod_ssl.html#sslrequire">SSLRequire</a></code> directive.
|
|
The differences are described in <code class="directive"><a href="./mod/mod_ssl.html#sslrequire">SSLRequire</a></code>'s documentation.</p>
|
|
</div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div>
|
|
<div class="section">
|
|
<h2><a name="compatibility" id="compatibility">Version History</a> <a title="Permanent link" href="#compatibility" class="permalink">¶</a></h2>
|
|
|
|
<p>The <code>req_novary</code> <a href="#functions">function</a>
|
|
is available for versions 2.4.4 and later.</p>
|
|
<p>The <code>SERVER_PROTOCOL_VERSION</code>,
|
|
<code>SERVER_PROTOCOL_VERSION_MAJOR</code> and
|
|
<code>SERVER_PROTOCOL_VERSION_MINOR</code>
|
|
<a href="#vars">variables</a>
|
|
are available for versions 2.5.0 and later.</p>
|
|
</div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div>
|
|
<div class="section">
|
|
<h2><a name="examples" id="examples">Example expressions</a> <a title="Permanent link" href="#examples" class="permalink">¶</a></h2>
|
|
|
|
|
|
<p>The following examples show how expressions might be used to
|
|
evaluate requests:</p>
|
|
|
|
|
|
<pre class="prettyprint lang-config"># Compare the host name to example.com and redirect to www.example.com if it matches
|
|
<If "%{HTTP_HOST} == 'example.com'">
|
|
Redirect permanent "/" "http://www.example.com/"
|
|
</If>
|
|
|
|
# Force text/plain if requesting a file with the query string contains 'forcetext'
|
|
<If "%{QUERY_STRING} =~ /forcetext/">
|
|
ForceType text/plain
|
|
</If>
|
|
|
|
# Only allow access to this content during business hours
|
|
<Directory "/foo/bar/business">
|
|
Require expr %{TIME_HOUR} -gt 9 && %{TIME_HOUR} -lt 17
|
|
</Directory>
|
|
|
|
# Check a HTTP header for a list of values
|
|
<If "%{HTTP:X-example-header} in { 'foo', 'bar', 'baz' }">
|
|
Header set matched true
|
|
</If>
|
|
|
|
# Check an environment variable for a regular expression, negated.
|
|
<If "! reqenv('REDIRECT_FOO') =~ /bar/">
|
|
Header set matched true
|
|
</If>
|
|
|
|
# Check result of URI mapping by running in Directory context with -f
|
|
<Directory "/var/www">
|
|
AddEncoding x-gzip gz
|
|
<If "-f '%{REQUEST_FILENAME}.unzipme' && ! %{HTTP:Accept-Encoding} =~ /gzip/">
|
|
SetOutputFilter INFLATE
|
|
</If>
|
|
</Directory>
|
|
|
|
# Check against the client IP
|
|
<If "-R '192.168.1.0/24'">
|
|
Header set matched true
|
|
</If>
|
|
|
|
# Function examples in boolean context
|
|
<If "md5('foo') == 'acbd18db4cc2f85cedef654fccc4a4d8'">
|
|
Header set checksum-matched true
|
|
</If>
|
|
|
|
Require expr replace(%{REQUEST_METHOD}, 'E', 'O') == 'GET'"
|
|
|
|
# Function example in string context
|
|
Header set foo-checksum "expr=%{md5:foo}"
|
|
|
|
# This delays the evaluation of the condition clause compared to <If>
|
|
Header always set CustomHeader my-value "expr=%{REQUEST_URI} =~ m#^/special_path\.php$#"
|
|
|
|
# Add a header to forward client's certificate SAN to some backend
|
|
RequestHeader set X-Client-SAN "expr=%{:join PeerExtList('subjectAltName'):}"
|
|
|
|
# Require that the remote IP be in the client's certificate SAN
|
|
Require expr %{REMOTE_ADDR} -in split s/.*?IP Address:([^,]+)/$1/, PeerExtList('subjectAltName')
|
|
# or alternatively:
|
|
Require expr "IP Address:%{REMOTE_ADDR}" -in split/, /, join PeerExtList('subjectAltName')
|
|
|
|
# Conditional logging
|
|
CustomLog logs/access-errors.log common "expr=%{REQUEST_STATUS} >= 400"
|
|
CustomLog logs/access-errors-specific.log common "expr=%{REQUEST_STATUS} -in {'405','410'}"</pre>
|
|
|
|
</div></div>
|
|
<div class="bottomlang">
|
|
<p><span>Available Languages: </span><a href="./en/expr.html" title="English"> en </a> |
|
|
<a href="./fr/expr.html" hreflang="fr" rel="alternate" title="Français"> fr </a></p>
|
|
</div><div class="top"><a href="#page-header"><img src="./images/up.gif" alt="top" /></a></div><div class="section"><h2><a id="comments_section" name="comments_section">Comments</a></h2><div class="warning"><strong>Notice:</strong><br />This is not a Q&A section. Comments placed here should be pointed towards suggestions on improving the documentation or server, and may be removed by our moderators if they are either implemented or considered invalid/off-topic. Questions on how to manage the Apache HTTP Server should be directed at either our IRC channel, #httpd, on Libera.chat, or sent to our <a href="https://httpd.apache.org/lists.html">mailing lists</a>.</div>
|
|
<script type="text/javascript"><!--//--><![CDATA[//><!--
|
|
var comments_shortname = 'httpd';
|
|
var comments_identifier = 'http://httpd.apache.org/docs/trunk/expr.html';
|
|
(function(w, d) {
|
|
if (w.location.hostname.toLowerCase() == "httpd.apache.org") {
|
|
d.write('<div id="comments_thread"><\/div>');
|
|
var s = d.createElement('script');
|
|
s.type = 'text/javascript';
|
|
s.async = true;
|
|
s.src = 'https://comments.apache.org/show_comments.lua?site=' + comments_shortname + '&page=' + comments_identifier;
|
|
(d.getElementsByTagName('head')[0] || d.getElementsByTagName('body')[0]).appendChild(s);
|
|
}
|
|
else {
|
|
d.write('<div id="comments_thread">Comments are disabled for this page at the moment.<\/div>');
|
|
}
|
|
})(window, document);
|
|
//--><!]]></script></div><div id="footer">
|
|
<p class="apache">Copyright 2023 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/quickreference.html">Directives</a> | <a href="http://wiki.apache.org/httpd/FAQ">FAQ</a> | <a href="./glossary.html">Glossary</a> | <a href="./sitemap.html">Sitemap</a></p></div><script type="text/javascript"><!--//--><![CDATA[//><!--
|
|
if (typeof(prettyPrint) !== 'undefined') {
|
|
prettyPrint();
|
|
}
|
|
//--><!]]></script>
|
|
</body></html> |