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diff --git a/rubbos/app/apache2/manual/suexec.html.en b/rubbos/app/apache2/manual/suexec.html.en deleted file mode 100644 index cb50bd9a..00000000 --- a/rubbos/app/apache2/manual/suexec.html.en +++ /dev/null @@ -1,617 +0,0 @@ -<?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>suEXEC Support - 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></div><div id="page-content"><div id="preamble"><h1>suEXEC Support</h1> -<div class="toplang"> -<p><span>Available Languages: </span><a href="./en/suexec.html" title="English"> en </a> | -<a href="./ja/suexec.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> | -<a href="./ko/suexec.html" hreflang="ko" rel="alternate" title="Korean"> ko </a> | -<a href="./tr/suexec.html" hreflang="tr" rel="alternate" title="Türkçe"> tr </a></p> -</div> - - <p>The <strong>suEXEC</strong> feature provides - Apache users the ability - to run <strong>CGI</strong> and <strong>SSI</strong> programs - under user IDs different from the user ID of the calling - web server. Normally, when a CGI or SSI program executes, it - runs as the same user who is running the web server.</p> - - <p>Used properly, this feature can reduce - considerably the security risks involved with allowing users to - develop and run private CGI or SSI programs. However, if suEXEC - is improperly configured, it can cause any number of problems - and possibly create new holes in your computer's security. If - you aren't familiar with managing <em>setuid root</em> programs - and the security issues they present, we highly recommend that - you not consider using suEXEC.</p> - </div> -<div id="quickview"><ul id="toc"><li><img alt="" src="./images/down.gif" /> <a href="#before">Before we begin</a></li> -<li><img alt="" src="./images/down.gif" /> <a href="#model">suEXEC Security Model</a></li> -<li><img alt="" src="./images/down.gif" /> <a href="#install">Configuring & Installing - suEXEC</a></li> -<li><img alt="" src="./images/down.gif" /> <a href="#enable">Enabling & Disabling - suEXEC</a></li> -<li><img alt="" src="./images/down.gif" /> <a href="#usage">Using suEXEC</a></li> -<li><img alt="" src="./images/down.gif" /> <a href="#debug">Debugging suEXEC</a></li> -<li><img alt="" src="./images/down.gif" /> <a href="#jabberwock">Beware the Jabberwock: - Warnings & Examples</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="before" id="before">Before we begin</a></h2> - - <p>Before jumping head-first into this document, - you should be aware of the assumptions made on the part of the - Apache Group and this document.</p> - - <p>First, it is assumed that you are using a UNIX - derivative operating system that is capable of - <strong>setuid</strong> and <strong>setgid</strong> operations. - All command examples are given in this regard. Other platforms, - if they are capable of supporting suEXEC, may differ in their - configuration.</p> - - <p>Second, it is assumed you are familiar with - some basic concepts of your computer's security and its - administration. This involves an understanding of - <strong>setuid/setgid</strong> operations and the various - effects they may have on your system and its level of - security.</p> - - <p>Third, it is assumed that you are using an - <strong>unmodified</strong> version of suEXEC code. All code - for suEXEC has been carefully scrutinized and tested by the - developers as well as numerous beta testers. Every precaution - has been taken to ensure a simple yet solidly safe base of - code. Altering this code can cause unexpected problems and new - security risks. It is <strong>highly</strong> recommended you - not alter the suEXEC code unless you are well versed in the - particulars of security programming and are willing to share - your work with the Apache Group for consideration.</p> - - <p>Fourth, and last, it has been the decision of - the Apache Group to <strong>NOT</strong> make suEXEC part of - the default installation of Apache. To this end, suEXEC - configuration requires of the administrator careful attention - to details. After due consideration has been given to the - various settings for suEXEC, the administrator may install - suEXEC through normal installation methods. The values for - these settings need to be carefully determined and specified by - the administrator to properly maintain system security during - the use of suEXEC functionality. It is through this detailed - process that the Apache Group hopes to limit suEXEC - installation only to those who are careful and determined - enough to use it.</p> - - <p>Still with us? Yes? Good. Let's move on!</p> -</div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div> -<div class="section"> -<h2><a name="model" id="model">suEXEC Security Model</a></h2> - - <p>Before we begin configuring and installing - suEXEC, we will first discuss the security model you are about - to implement. By doing so, you may better understand what - exactly is going on inside suEXEC and what precautions are - taken to ensure your system's security.</p> - - <p><strong>suEXEC</strong> is based on a setuid - "wrapper" program that is called by the main Apache web server. - This wrapper is called when an HTTP request is made for a CGI - or SSI program that the administrator has designated to run as - a userid other than that of the main server. When such a - request is made, Apache provides the suEXEC wrapper with the - program's name and the user and group IDs under which the - program is to execute.</p> - - <p>The wrapper then employs the following process - to determine success or failure -- if any one of these - conditions fail, the program logs the failure and exits with an - error, otherwise it will continue:</p> - - <ol> - <li> - <strong>Is the user executing this wrapper a valid user of - this system?</strong> - - <p class="indent"> - This is to ensure that the user executing the wrapper is - truly a user of the system. - </p> - </li> - - <li> - <strong>Was the wrapper called with the proper number of - arguments?</strong> - - <p class="indent"> - The wrapper will only execute if it is given the proper - number of arguments. The proper argument format is known - to the Apache web server. If the wrapper is not receiving - the proper number of arguments, it is either being - hacked, or there is something wrong with the suEXEC - portion of your Apache binary. - </p> - </li> - - <li> - <strong>Is this valid user allowed to run the - wrapper?</strong> - - <p class="indent"> - Is this user the user allowed to run this wrapper? Only - one user (the Apache user) is allowed to execute this - program. - </p> - </li> - - <li> - <strong>Does the target CGI or SSI program have an unsafe - hierarchical reference?</strong> - - <p class="indent"> - Does the target CGI or SSI program's path contain a leading - '/' or have a '..' backreference? These are not allowed; the - target CGI/SSI program must reside within suEXEC's document - root (see <code>--with-suexec-docroot=<em>DIR</em></code> - below). - </p> - </li> - - <li> - <strong>Is the target user name valid?</strong> - - <p class="indent"> - Does the target user exist? - </p> - </li> - - <li> - <strong>Is the target group name valid?</strong> - - <p class="indent"> - Does the target group exist? - </p> - </li> - - <li> - <strong>Is the target user <em>NOT</em> superuser?</strong> - - - <p class="indent"> - Presently, suEXEC does not allow <code><em>root</em></code> - to execute CGI/SSI programs. - </p> - </li> - - <li> - <strong>Is the target userid <em>ABOVE</em> the minimum ID - number?</strong> - - <p class="indent"> - The minimum user ID number is specified during - configuration. This allows you to set the lowest possible - userid that will be allowed to execute CGI/SSI programs. - This is useful to block out "system" accounts. - </p> - </li> - - <li> - <strong>Is the target group <em>NOT</em> the superuser - group?</strong> - - <p class="indent"> - Presently, suEXEC does not allow the <code><em>root</em></code> - group to execute CGI/SSI programs. - </p> - </li> - - <li> - <strong>Is the target groupid <em>ABOVE</em> the minimum ID - number?</strong> - - <p class="indent"> - The minimum group ID number is specified during - configuration. This allows you to set the lowest possible - groupid that will be allowed to execute CGI/SSI programs. - This is useful to block out "system" groups. - </p> - </li> - - <li> - <strong>Can the wrapper successfully become the target user - and group?</strong> - - <p class="indent"> - Here is where the program becomes the target user and - group via setuid and setgid calls. The group access list - is also initialized with all of the groups of which the - user is a member. - </p> - </li> - - <li> - <strong>Can we change directory to the one in which the target - CGI/SSI program resides?</strong> - - <p class="indent"> - If it doesn't exist, it can't very well contain files. If we - can't change directory to it, it might aswell not exist. - </p> - </li> - - <li> - <strong>Is the directory within the Apache - webspace?</strong> - - <p class="indent"> - If the request is for a regular portion of the server, is - the requested directory within suEXEC's document root? If - the request is for a <code class="directive"><a href="./mod/mod_userdir.html#userdir">UserDir</a></code>, is the requested directory - within the directory configured as suEXEC's userdir (see - <a href="#install">suEXEC's configuration options</a>)? - </p> - </li> - - <li> - <strong>Is the directory <em>NOT</em> writable by anyone - else?</strong> - - <p class="indent"> - We don't want to open up the directory to others; only - the owner user may be able to alter this directories - contents. - </p> - </li> - - <li> - <strong>Does the target CGI/SSI program exist?</strong> - - <p class="indent"> - If it doesn't exists, it can't very well be executed. - </p> - </li> - - <li> - <strong>Is the target CGI/SSI program <em>NOT</em> writable - by anyone else?</strong> - - <p class="indent"> - We don't want to give anyone other than the owner the - ability to change the CGI/SSI program. - </p> - </li> - - <li> - <strong>Is the target CGI/SSI program <em>NOT</em> setuid or - setgid?</strong> - - <p class="indent"> - We do not want to execute programs that will then change - our UID/GID again. - </p> - </li> - - <li> - <strong>Is the target user/group the same as the program's - user/group?</strong> - - <p class="indent"> - Is the user the owner of the file? - </p> - </li> - - <li> - <strong>Can we successfully clean the process environment - to ensure safe operations?</strong> - - <p class="indent"> - suEXEC cleans the process' environment by establishing a - safe execution PATH (defined during configuration), as - well as only passing through those variables whose names - are listed in the safe environment list (also created - during configuration). - </p> - </li> - - <li> - <strong>Can we successfully become the target CGI/SSI program - and execute?</strong> - - <p class="indent"> - Here is where suEXEC ends and the target CGI/SSI program begins. - </p> - </li> - </ol> - - <p>This is the standard operation of the - suEXEC wrapper's security model. It is somewhat stringent and - can impose new limitations and guidelines for CGI/SSI design, - but it was developed carefully step-by-step with security in - mind.</p> - - <p>For more information as to how this security - model can limit your possibilities in regards to server - configuration, as well as what security risks can be avoided - with a proper suEXEC setup, see the <a href="#jabberwock">"Beware the Jabberwock"</a> section of this - document.</p> -</div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div> -<div class="section"> -<h2><a name="install" id="install">Configuring & Installing - suEXEC</a></h2> - - <p>Here's where we begin the fun.</p> - - <p><strong>suEXEC configuration - options</strong><br /> - </p> - - <dl> - <dt><code>--enable-suexec</code></dt> - - <dd>This option enables the suEXEC feature which is never - installed or activated by default. At least one - <code>--with-suexec-xxxxx</code> option has to be provided - together with the <code>--enable-suexec</code> option to let - APACI accept your request for using the suEXEC feature.</dd> - - <dt><code>--with-suexec-bin=<em>PATH</em></code></dt> - - <dd>The path to the <code>suexec</code> binary must be hard-coded - in the server for security reasons. Use this option to override - the default path. <em>e.g.</em> - <code>--with-suexec-bin=/usr/bin/suexec</code></dd> - - <dt><code>--with-suexec-caller=<em>UID</em></code></dt> - - <dd>The <a href="mod/mpm_common.html#user">username</a> under which - Apache normally runs. This is the only user allowed to - execute this program.</dd> - - <dt><code>--with-suexec-userdir=<em>DIR</em></code></dt> - - <dd>Define to be the subdirectory under users' home - directories where suEXEC access should be allowed. All - executables under this directory will be executable by suEXEC - as the user so they should be "safe" programs. If you are - using a "simple" <code class="directive"><a href="./mod/mod_userdir.html#userdir">UserDir</a></code> - directive (ie. one without a "*" in it) this should be set to the same - value. suEXEC will not work properly in cases where the <code class="directive"><a href="./mod/mod_userdir.html#userdir">UserDir</a></code> directive points to - a location that is not the same as the user's home directory - as referenced in the <code>passwd</code> file. Default value is - "<code>public_html</code>".<br /> - If you have virtual hosts with a different <code class="directive"><a href="./mod/mod_userdir.html#userdir">UserDir</a></code> for each, - you will need to define them to all reside in one parent - directory; then name that parent directory here. <strong>If - this is not defined properly, "~userdir" cgi requests will - not work!</strong></dd> - - <dt><code>--with-suexec-docroot=<em>DIR</em></code></dt> - - <dd>Define as the DocumentRoot set for Apache. This will be - the only hierarchy (aside from <code class="directive"><a href="./mod/mod_userdir.html#userdir">UserDir</a></code>s) that can be used for suEXEC behavior. The - default directory is the <code>--datadir</code> value with the suffix - "<code>/htdocs</code>", <em>e.g.</em> if you configure with - "<code>--datadir=/home/apache</code>" the directory - "<code>/home/apache/htdocs</code>" is used as document root for the - suEXEC wrapper.</dd> - - <dt><code>--with-suexec-uidmin=<em>UID</em></code></dt> - - <dd>Define this as the lowest UID allowed to be a target user - for suEXEC. For most systems, 500 or 100 is common. Default - value is 100.</dd> - - <dt><code>--with-suexec-gidmin=<em>GID</em></code></dt> - - <dd>Define this as the lowest GID allowed to be a target - group for suEXEC. For most systems, 100 is common and - therefore used as default value.</dd> - - <dt><code>--with-suexec-logfile=<em>FILE</em></code></dt> - - <dd>This defines the filename to which all suEXEC - transactions and errors are logged (useful for auditing and - debugging purposes). By default the logfile is named - "<code>suexec_log</code>" and located in your standard logfile - directory (<code>--logfiledir</code>).</dd> - - <dt><code>--with-suexec-safepath=<em>PATH</em></code></dt> - - <dd>Define a safe PATH environment to pass to CGI - executables. Default value is - "<code>/usr/local/bin:/usr/bin:/bin</code>".</dd> - </dl> - - <h3>Compiling and installing the suEXEC wrapper</h3> - - - <p>If you have enabled the suEXEC feature with the - <code>--enable-suexec</code> option the <code>suexec</code> binary - (together with Apache itself) is automatically built if you execute - the <code>make</code> command.</p> - - <p>After all components have been built you can execute the - command <code>make install</code> to install them. The binary image - <code>suexec</code> is installed in the directory defined by the - <code>--sbindir</code> option. The default location is - "/usr/local/apache2/bin/suexec".</p> - - <p>Please note that you need <strong><em>root - privileges</em></strong> for the installation step. In order - for the wrapper to set the user ID, it must be installed as - owner <code><em>root</em></code> and must have the setuserid - execution bit set for file modes.</p> - - - <h3>Setting paranoid permissions</h3> - - - <p>Although the suEXEC wrapper will check to ensure that its - caller is the correct user as specified with the - <code>--with-suexec-caller</code> <code class="program"><a href="./programs/configure.html">configure</a></code> - option, there is - always the possibility that a system or library call suEXEC uses - before this check may be exploitable on your system. To counter - this, and because it is best-practise in general, you should use - filesystem permissions to ensure that only the group Apache - runs as may execute suEXEC.</p> - - <p>If for example, your web server is configured to run as:</p> - - <div class="example"><p><code> - User www<br /> - Group webgroup<br /> - </code></p></div> - - <p>and <code class="program"><a href="./programs/suexec.html">suexec</a></code> is installed at - "/usr/local/apache2/bin/suexec", you should run:</p> - - <div class="example"><p><code> - chgrp webgroup /usr/local/apache2/bin/suexec<br /> - chmod 4750 /usr/local/apache2/bin/suexec<br /> - </code></p></div> - - <p>This will ensure that only the group Apache runs as can even - execute the suEXEC wrapper.</p> - -</div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div> -<div class="section"> -<h2><a name="enable" id="enable">Enabling & Disabling - suEXEC</a></h2> - - <p>Upon startup of Apache, it looks for the file - <code class="program"><a href="./programs/suexec.html">suexec</a></code> in the directory defined by the - <code>--sbindir</code> option (default is - "/usr/local/apache/bin/suexec"). If Apache finds a properly - configured suEXEC wrapper, it will print the following message - to the error log:</p> - -<div class="example"><p><code> - [notice] suEXEC mechanism enabled (wrapper: <var>/path/to/suexec</var>) -</code></p></div> - - <p>If you don't see this message at server startup, the server is - most likely not finding the wrapper program where it expects - it, or the executable is not installed <em>setuid root</em>.</p> - - <p>If you want to enable the suEXEC mechanism for the first time - and an Apache server is already running you must kill and - restart Apache. Restarting it with a simple HUP or USR1 signal - will not be enough. </p> - <p>If you want to disable suEXEC you should kill and restart - Apache after you have removed the <code class="program"><a href="./programs/suexec.html">suexec</a></code> file.</p> -</div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div> -<div class="section"> -<h2><a name="usage" id="usage">Using suEXEC</a></h2> - - <p>Requests for CGI programs will call the suEXEC wrapper only if - they are for a virtual host containing a <code class="directive"><a href="./mod/mod_suexec.html#suexecusergroup">SuexecUserGroup</a></code> directive or if - they are processed by <code class="module"><a href="./mod/mod_userdir.html">mod_userdir</a></code>.</p> - - <p><strong>Virtual Hosts:</strong><br /> One way to use the suEXEC - wrapper is through the <code class="directive"><a href="./mod/mod_suexec.html#suexecusergroup">SuexecUserGroup</a></code> directive in - <code class="directive"><a href="./mod/core.html#virtualhost">VirtualHost</a></code> definitions. By - setting this directive to values different from the main server - user ID, all requests for CGI resources will be executed as the - <em>User</em> and <em>Group</em> defined for that <code class="directive"><a href="./mod/core.html#virtualhost"><VirtualHost></a></code>. If this - directive is not specified for a <code class="directive"><a href="./mod/core.html#virtualhost"><VirtualHost></a></code> then the main server userid - is assumed.</p> - - <p><strong>User directories:</strong><br /> Requests that are - processed by <code class="module"><a href="./mod/mod_userdir.html">mod_userdir</a></code> will call the suEXEC - wrapper to execute CGI programs under the userid of the requested - user directory. The only requirement needed for this feature to - work is for CGI execution to be enabled for the user and that the - script must meet the scrutiny of the <a href="#model">security - checks</a> above. See also the - <code>--with-suexec-userdir</code> <a href="#install">compile - time option</a>.</p> </div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div> -<div class="section"> -<h2><a name="debug" id="debug">Debugging suEXEC</a></h2> - - <p>The suEXEC wrapper will write log information - to the file defined with the <code>--with-suexec-logfile</code> - option as indicated above. If you feel you have configured and - installed the wrapper properly, have a look at this log and the - error_log for the server to see where you may have gone astray.</p> - -</div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div> -<div class="section"> -<h2><a name="jabberwock" id="jabberwock">Beware the Jabberwock: - Warnings & Examples</a></h2> - - <p><strong>NOTE!</strong> This section may not be - complete. For the latest revision of this section of the - documentation, see the Apache Group's <a href="http://httpd.apache.org/docs/2.0/suexec.html">Online - Documentation</a> version.</p> - - <p>There are a few points of interest regarding - the wrapper that can cause limitations on server setup. Please - review these before submitting any "bugs" regarding suEXEC.</p> - - <ul> - <li><strong>suEXEC Points Of Interest</strong></li> - - <li> - Hierarchy limitations - - <p class="indent"> - For security and efficiency reasons, all suEXEC requests - must remain within either a top-level document root for - virtual host requests, or one top-level personal document - root for userdir requests. For example, if you have four - VirtualHosts configured, you would need to structure all - of your VHosts' document roots off of one main Apache - document hierarchy to take advantage of suEXEC for - VirtualHosts. (Example forthcoming.) - </p> - </li> - - <li> - suEXEC's PATH environment variable - - <p class="indent"> - This can be a dangerous thing to change. Make certain - every path you include in this define is a - <strong>trusted</strong> directory. You don't want to - open people up to having someone from across the world - running a trojan horse on them. - </p> - </li> - - <li> - Altering the suEXEC code - - <p class="indent"> - Again, this can cause <strong>Big Trouble</strong> if you - try this without knowing what you are doing. Stay away - from it if at all possible. - </p> - </li> - </ul> - -</div></div> -<div class="bottomlang"> -<p><span>Available Languages: </span><a href="./en/suexec.html" title="English"> en </a> | -<a href="./ja/suexec.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> | -<a href="./ko/suexec.html" hreflang="ko" rel="alternate" title="Korean"> ko </a> | -<a href="./tr/suexec.html" hreflang="tr" rel="alternate" title="Türkçe"> tr </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>
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