--- /dev/null
+<?xml version="1.0" encoding="ISO-8859-1"?>
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
+<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head><!--
+ XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
+ This file is generated from xml source: DO NOT EDIT
+ XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
+ -->
+<title>Authentication, Authorization and Access Control - Apache HTTP Server</title>
+<link href="../style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" />
+<link href="../style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" />
+<link href="../style/css/manual-print.css" rel="stylesheet" media="print" type="text/css" />
+<link href="../images/favicon.ico" rel="shortcut icon" /></head>
+<body id="manual-page"><div id="page-header">
+<p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/directives.html">Directives</a> | <a href="../faq/">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p>
+<p class="apache">Apache HTTP Server Version 2.0</p>
+<img alt="" src="../images/feather.gif" /></div>
+<div class="up"><a href="./"><img title="<-" alt="<-" src="../images/left.gif" /></a></div>
+<div id="path">
+<a href="http://www.apache.org/">Apache</a> > <a href="http://httpd.apache.org/">HTTP Server</a> > <a href="http://httpd.apache.org/docs/">Documentation</a> > <a href="../">Version 2.0</a> > <a href="./">How-To / Tutorials</a></div><div id="page-content"><div id="preamble"><h1>Authentication, Authorization and Access Control</h1>
+<div class="toplang">
+<p><span>Available Languages: </span><a href="../en/howto/auth.html" title="English"> en </a> |
+<a href="../es/howto/auth.html" hreflang="es" rel="alternate" title="Español"> es </a> |
+<a href="../ja/howto/auth.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> |
+<a href="../ko/howto/auth.html" hreflang="ko" rel="alternate" title="Korean"> ko </a></p>
+</div>
+
+ <p>Authentication is any process by which you verify that
+ someone is who they claim they are. Authorization is any
+ process by which someone is allowed to be where they want to
+ go, or to have information that they want to have.</p>
+</div>
+<div id="quickview"><ul id="toc"><li><img alt="" src="../images/down.gif" /> <a href="#related">Related Modules and Directives</a></li>
+<li><img alt="" src="../images/down.gif" /> <a href="#introduction">Introduction</a></li>
+<li><img alt="" src="../images/down.gif" /> <a href="#theprerequisites">The Prerequisites</a></li>
+<li><img alt="" src="../images/down.gif" /> <a href="#gettingitworking">Getting it working</a></li>
+<li><img alt="" src="../images/down.gif" /> <a href="#lettingmorethanonepersonin">Letting more than one
+person in</a></li>
+<li><img alt="" src="../images/down.gif" /> <a href="#possibleproblems">Possible problems</a></li>
+<li><img alt="" src="../images/down.gif" /> <a href="#whatotherneatstuffcanido">What other neat stuff can I
+do?</a></li>
+<li><img alt="" src="../images/down.gif" /> <a href="#moreinformation">More information</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="related" id="related">Related Modules and Directives</a></h2>
+ <table class="related"><tr><th>Related Modules</th><th>Related Directives</th></tr><tr><td><ul><li><code class="module"><a href="../mod/mod_auth.html">mod_auth</a></code></li><li><code class="module"><a href="../mod/mod_access.html">mod_access</a></code></li></ul></td><td><ul><li><code class="directive"><a href="../mod/mod_access.html#allow">Allow</a></code></li><li><code class="directive"><a href="../mod/mod_auth.html#authgroupfile">AuthGroupFile</a></code></li><li><code class="directive"><a href="../mod/core.html#authname">AuthName</a></code></li><li><code class="directive"><a href="../mod/core.html#authtype">AuthType</a></code></li><li><code class="directive"><a href="../mod/mod_auth.html#authuserfile">AuthUserFile</a></code></li><li><code class="directive"><a href="../mod/mod_access.html#deny">Deny</a></code></li><li><code class="directive"><a href="../mod/core.html#options">Options</a></code></li><li><code class="directive"><a href="../mod/core.html#require">Require</a></code></li></ul></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="introduction" id="introduction">Introduction</a></h2>
+ <p>If you have information on your web site that is sensitive
+ or intended for only a small group of people, the techniques in
+ this article will help you make sure that the people that see
+ those pages are the people that you wanted to see them.</p>
+
+ <p>This article covers the "standard" way of protecting parts
+ of your web site that most of you are going to use.</p>
+</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
+<div class="section">
+<h2><a name="theprerequisites" id="theprerequisites">The Prerequisites</a></h2>
+ <p>The directives discussed in this article will need to go
+ either in your main server configuration file (typically in a
+ <code class="directive"><a href="../mod/core.html#directory"><Directory></a></code> section), or
+ in per-directory configuration files (<code>.htaccess</code> files).</p>
+
+ <p>If you plan to use <code>.htaccess</code> files, you will
+ need to have a server configuration that permits putting
+ authentication directives in these files. This is done with the
+ <code class="directive"><a href="../mod/core.html#allowoverride">AllowOverride</a></code> directive, which
+ specifies which directives, if any, may be put in per-directory
+ configuration files.</p>
+
+ <p>Since we're talking here about authentication, you will need
+ an <code class="directive"><a href="../mod/core.html#allowoverride">AllowOverride</a></code> directive like the
+ following:</p>
+
+ <div class="example"><p><code>
+ AllowOverride AuthConfig
+ </code></p></div>
+
+ <p>Or, if you are just going to put the directives directly in
+ your main server configuration file, you will of course need to
+ have write permission to that file.</p>
+
+ <p>And you'll need to know a little bit about the directory
+ structure of your server, in order to know where some files are
+ kept. This should not be terribly difficult, and I'll try to
+ make this clear when we come to that point.</p>
+</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
+<div class="section">
+<h2><a name="gettingitworking" id="gettingitworking">Getting it working</a></h2>
+ <p>Here's the basics of password protecting a directory on your
+ server.</p>
+
+ <p>You'll need to create a password file. This file should be
+ placed somewhere not accessible from the web. This is so that
+ folks cannot download the password file. For example, if your
+ documents are served out of <code>/usr/local/apache/htdocs</code> you
+ might want to put the password file(s) in
+ <code>/usr/local/apache/passwd</code>.</p>
+
+ <p>To create the file, use the <code class="program"><a href="../programs/htpasswd.html">htpasswd</a></code> utility that
+ came with Apache. This will be located in the <code>bin</code> directory
+ of wherever you installed Apache. To create the file, type:</p>
+
+ <div class="example"><p><code>
+ htpasswd -c /usr/local/apache/passwd/passwords rbowen
+ </code></p></div>
+
+ <p><code class="program"><a href="../programs/htpasswd.html">htpasswd</a></code> will ask you for the password, and
+ then ask you to type it again to confirm it:</p>
+
+ <div class="example"><p><code>
+ # htpasswd -c /usr/local/apache/passwd/passwords rbowen<br />
+ New password: mypassword<br />
+ Re-type new password: mypassword<br />
+ Adding password for user rbowen
+ </code></p></div>
+
+ <p>If <code class="program"><a href="../programs/htpasswd.html">htpasswd</a></code> is not in your path, of course
+ you'll have to type the full path to the file to get it to run.
+ On my server, it's located at
+ <code>/usr/local/apache/bin/htpasswd</code></p>
+
+ <p>Next, you'll need to configure the server to request a
+ password and tell the server which users are allowed access.
+ You can do this either by editing the <code>httpd.conf</code>
+ file or using an <code>.htaccess</code> file. For example, if
+ you wish to protect the directory
+ <code>/usr/local/apache/htdocs/secret</code>, you can use the
+ following directives, either placed in the file
+ <code>/usr/local/apache/htdocs/secret/.htaccess</code>, or
+ placed in <code>httpd.conf</code> inside a <Directory
+ /usr/local/apache/apache/htdocs/secret> section.</p>
+
+ <div class="example"><p><code>
+ AuthType Basic<br />
+ AuthName "Restricted Files"<br />
+ AuthUserFile /usr/local/apache/passwd/passwords<br />
+ Require user rbowen
+ </code></p></div>
+
+ <p>Let's examine each of those directives individually. The <code class="directive"><a href="../mod/core.html#authtype">AuthType</a></code> directive selects
+ that method that is used to authenticate the user. The most
+ common method is <code>Basic</code>, and this is the method
+ implemented by <code class="module"><a href="../mod/mod_auth.html">mod_auth</a></code>. It is important to be aware,
+ however, that Basic authentication sends the password from the client to
+ the browser unencrypted. This method should therefore not be used for
+ highly sensitive data. Apache supports one other authentication method:
+ <code>AuthType Digest</code>. This method is implemented by <code class="module"><a href="../mod/mod_auth_digest.html">mod_auth_digest</a></code> and is much more secure. Only the most recent
+ versions of clients are known to support Digest authentication.</p>
+
+ <p>The <code class="directive"><a href="../mod/core.html#authname">AuthName</a></code> directive sets
+ the <dfn>Realm</dfn> to be used in the authentication. The realm serves
+ two major functions. First, the client often presents this information to
+ the user as part of the password dialog box. Second, it is used by the
+ client to determine what password to send for a given authenticated
+ area.</p>
+
+ <p>So, for example, once a client has authenticated in the
+ <code>"Restricted Files"</code> area, it will automatically
+ retry the same password for any area on the same server that is
+ marked with the <code>"Restricted Files"</code> Realm.
+ Therefore, you can prevent a user from being prompted more than
+ once for a password by letting multiple restricted areas share
+ the same realm. Of course, for security reasons, the client
+ will always need to ask again for the password whenever the
+ hostname of the server changes.</p>
+
+ <p>The <code class="directive"><a href="../mod/mod_auth.html#authuserfile">AuthUserFile</a></code>
+ directive sets the path to the password file that we just
+ created with <code class="program"><a href="../programs/htpasswd.html">htpasswd</a></code>. If you have a large number
+ of users, it can be quite slow to search through a plain text
+ file to authenticate the user on each request. Apache also has
+ the ability to store user information in fast database files.
+ The <code class="module"><a href="../mod/mod_auth_dbm.html">mod_auth_dbm</a></code> module provides the <code class="directive"><a href="../mod/mod_auth_dbm.html#authdbmuserfile">AuthDBMUserFile</a></code> directive. These
+ files can be created and manipulated with the <code class="program"><a href="../programs/dbmmanage.html">dbmmanage</a></code> program. Many
+ other types of authentication options are available from third
+ party modules in the <a href="http://modules.apache.org/">Apache Modules
+ Database</a>.</p>
+
+ <p>Finally, the <code class="directive"><a href="../mod/core.html#require">Require</a></code>
+ directive provides the authorization part of the process by
+ setting the user that is allowed to access this region of the
+ server. In the next section, we discuss various ways to use the
+ <code class="directive"><a href="../mod/core.html#require">Require</a></code> directive.</p>
+</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
+<div class="section">
+<h2><a name="lettingmorethanonepersonin" id="lettingmorethanonepersonin">Letting more than one
+person in</a></h2>
+ <p>The directives above only let one person (specifically
+ someone with a username of <code>rbowen</code>) into the
+ directory. In most cases, you'll want to let more than one
+ person in. This is where the <code class="directive"><a href="../mod/mod_auth.html#authgroupfile">AuthGroupFile</a></code> comes in.</p>
+
+ <p>If you want to let more than one person in, you'll need to
+ create a group file that associates group names with a list of
+ users in that group. The format of this file is pretty simple,
+ and you can create it with your favorite editor. The contents
+ of the file will look like this:</p>
+
+ <div class="example"><p><code>
+ GroupName: rbowen dpitts sungo rshersey
+ </code></p></div>
+
+ <p>That's just a list of the members of the group in a long
+ line separated by spaces.</p>
+
+ <p>To add a user to your already existing password file,
+ type:</p>
+
+ <div class="example"><p><code>
+ htpasswd /usr/local/apache/passwd/passwords dpitts
+ </code></p></div>
+
+ <p>You'll get the same response as before, but it will be
+ appended to the existing file, rather than creating a new file.
+ (It's the <code>-c</code> that makes it create a new password
+ file).</p>
+
+ <p>Now, you need to modify your <code>.htaccess</code> file to
+ look like the following:</p>
+
+ <div class="example"><p><code>
+ AuthType Basic<br />
+ AuthName "By Invitation Only"<br />
+ AuthUserFile /usr/local/apache/passwd/passwords<br />
+ AuthGroupFile /usr/local/apache/passwd/groups<br />
+ Require group GroupName
+ </code></p></div>
+
+ <p>Now, anyone that is listed in the group <code>GroupName</code>,
+ and has an entry in the <code>password</code> file, will be let in, if
+ they type the correct password.</p>
+
+ <p>There's another way to let multiple users in that is less
+ specific. Rather than creating a group file, you can just use
+ the following directive:</p>
+
+ <div class="example"><p><code>
+ Require valid-user
+ </code></p></div>
+
+ <p>Using that rather than the <code>Require user rbowen</code>
+ line will allow anyone in that is listed in the password file,
+ and who correctly enters their password. You can even emulate
+ the group behavior here, by just keeping a separate password
+ file for each group. The advantage of this approach is that
+ Apache only has to check one file, rather than two. The
+ disadvantage is that you have to maintain a bunch of password
+ files, and remember to reference the right one in the
+ <code class="directive"><a href="../mod/mod_auth.html#authuserfile">AuthUserFile</a></code> directive.</p>
+</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
+<div class="section">
+<h2><a name="possibleproblems" id="possibleproblems">Possible problems</a></h2>
+ <p>Because of the way that Basic authentication is specified,
+ your username and password must be verified every time you
+ request a document from the server. This is even if you're
+ reloading the same page, and for every image on the page (if
+ they come from a protected directory). As you can imagine, this
+ slows things down a little. The amount that it slows things
+ down is proportional to the size of the password file, because
+ it has to open up that file, and go down the list of users
+ until it gets to your name. And it has to do this every time a
+ page is loaded.</p>
+
+ <p>A consequence of this is that there's a practical limit to
+ how many users you can put in one password file. This limit
+ will vary depending on the performance of your particular
+ server machine, but you can expect to see slowdowns once you
+ get above a few hundred entries, and may wish to consider a
+ different authentication method at that time.</p>
+</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
+<div class="section">
+<h2><a name="whatotherneatstuffcanido" id="whatotherneatstuffcanido">What other neat stuff can I
+do?</a></h2>
+ <p>Authentication by username and password is only part of the
+ story. Frequently you want to let people in based on something
+ other than who they are. Something such as where they are
+ coming from.</p>
+
+ <p>The <code class="directive"><a href="../mod/mod_access.html#allow">Allow</a></code> and
+ <code class="directive"><a href="../mod/mod_access.html#deny">Deny</a></code> directives let
+ you allow and deny access based on the host name, or host
+ address, of the machine requesting a document. The
+ <code class="directive"><a href="../mod/mod_access.html#order">Order</a></code> directive goes
+ hand-in-hand with these two, and tells Apache in which order to
+ apply the filters.</p>
+
+ <p>The usage of these directives is:</p>
+
+ <div class="example"><p><code>
+ Allow from <var>address</var>
+ </code></p></div>
+
+ <p>where <var>address</var> is an IP address (or a partial IP
+ address) or a fully qualified domain name (or a partial domain
+ name); you may provide multiple addresses or domain names, if
+ desired.</p>
+
+ <p>For example, if you have someone spamming your message
+ board, and you want to keep them out, you could do the
+ following:</p>
+
+ <div class="example"><p><code>
+ Deny from 10.252.46.165
+ </code></p></div>
+
+ <p>Visitors coming from that address will not be able to see
+ the content covered by this directive. If, instead, you have a
+ machine name, rather than an IP address, you can use that.</p>
+
+ <div class="example"><p><code>
+ Deny from <var>host.example.com</var>
+ </code></p></div>
+
+ <p>And, if you'd like to block access from an entire domain,
+ you can specify just part of an address or domain name:</p>
+
+ <div class="example"><p><code>
+ Deny from <var>192.168.205</var><br />
+ Deny from <var>phishers.example.com</var> <var>moreidiots.example</var><br />
+ Deny from ke
+ </code></p></div>
+
+ <p>Using <code class="directive"><a href="../mod/mod_access.html#order">Order</a></code> will let you be
+ sure that you are actually restricting things to the group that you want
+ to let in, by combining a <code class="directive"><a href="../mod/mod_access.html#deny">Deny</a></code>
+ and an <code class="directive"><a href="../mod/mod_access.html#allow">Allow</a></code> directive:</p>
+
+ <div class="example"><p><code>
+ Order deny,allow<br />
+ Deny from all<br />
+ Allow from <var>dev.example.com</var>
+ </code></p></div>
+
+ <p>Listing just the <code class="directive"><a href="../mod/mod_access.html#allow">Allow</a></code>
+ directive would not do what you want, because it will let folks from that
+ host in, in addition to letting everyone in. What you want is to let
+ <em>only</em> those folks in.</p>
+</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
+<div class="section">
+<h2><a name="moreinformation" id="moreinformation">More information</a></h2>
+ <p>You should also read the documentation for <code class="module"><a href="../mod/mod_auth.html">mod_auth</a></code>
+ and <code class="module"><a href="../mod/mod_access.html">mod_access</a></code> which contain some more information
+ about how this all works.</p>
+</div></div>
+<div class="bottomlang">
+<p><span>Available Languages: </span><a href="../en/howto/auth.html" title="English"> en </a> |
+<a href="../es/howto/auth.html" hreflang="es" rel="alternate" title="Español"> es </a> |
+<a href="../ja/howto/auth.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> |
+<a href="../ko/howto/auth.html" hreflang="ko" rel="alternate" title="Korean"> ko </a></p>
+</div><div id="footer">
+<p class="apache">Copyright 2009 The Apache Software Foundation.<br />Licensed under the <a href="http://www.apache.org/licenses/LICENSE-2.0">Apache License, Version 2.0</a>.</p>
+<p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/directives.html">Directives</a> | <a href="../faq/">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p></div>
+</body></html>
\ No newline at end of file
Code Review / bottlenecks.git / blobdiff