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diff --git a/rubbos/app/apache2/manual/misc/known_client_problems.html.en b/rubbos/app/apache2/manual/misc/known_client_problems.html.en deleted file mode 100644 index cfc02954..00000000 --- a/rubbos/app/apache2/manual/misc/known_client_problems.html.en +++ /dev/null @@ -1,408 +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>Known Problems in Clients - 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="./">Miscellaneous Documentation</a></div><div id="page-content"><div id="preamble"><h1>Known Problems in Clients</h1> -<div class="toplang"> -<p><span>Available Languages: </span><a href="../en/misc/known_client_problems.html" title="English"> en </a></p> -</div> - - - <div class="warning"><h3>Warning:</h3> - <p>This document has not been fully updated - to take into account changes made in the 2.0 version of the - Apache HTTP Server. Some of the information may still be - relevant, but please use it with care.</p> - </div> - - <p>Over time the Apache Group has discovered or been notified - of problems with various clients which we have had to work - around, or explain. This document describes these problems and - the workarounds available. It's not arranged in any particular - order. Some familiarity with the standards is assumed, but not - necessary.</p> - - <p>For brevity, <em>Navigator</em> will refer to Netscape's - Navigator product (which in later versions was renamed - "Communicator" and various other names), and <em>MSIE</em> will - refer to Microsoft's Internet Explorer product. All trademarks - and copyrights belong to their respective companies. We welcome - input from the various client authors to correct - inconsistencies in this paper, or to provide us with exact - version numbers where things are broken/fixed.</p> - - <p>For reference, <a href="ftp://ds.internic.net/rfc/rfc1945.txt">RFC1945</a> - defines HTTP/1.0, and <a href="ftp://ds.internic.net/rfc/rfc2068.txt">RFC2068</a> - defines HTTP/1.1. Apache as of version 1.2 is an HTTP/1.1 - server (with an optional HTTP/1.0 proxy).</p> - - <p>Various of these workarounds are triggered by environment - variables. The admin typically controls which are set, and for - which clients, by using <code>mod_browser</code>. Unless - otherwise noted all of these workarounds exist in versions 1.2 - and later.</p> - - </div> -<div id="quickview"><ul id="toc"><li><img alt="" src="../images/down.gif" /> <a href="#trailing-crlf">Trailing CRLF on POSTs</a></li> -<li><img alt="" src="../images/down.gif" /> <a href="#broken-keepalive">Broken KeepAlive</a></li> -<li><img alt="" src="../images/down.gif" /> <a href="#force-response-1.0">Incorrect interpretation of - <code>HTTP/1.1</code> in response</a></li> -<li><img alt="" src="../images/down.gif" /> <a href="#msie4.0b2">Requests use HTTP/1.1 but - responses must be in HTTP/1.0</a></li> -<li><img alt="" src="../images/down.gif" /> <a href="#byte-257">Boundary problems with - header parsing</a></li> -<li><img alt="" src="../images/down.gif" /> <a href="#boundary-string">Multipart responses and - Quoted Boundary Strings</a></li> -<li><img alt="" src="../images/down.gif" /> <a href="#byterange-requests">Byterange Requests</a></li> -<li><img alt="" src="../images/down.gif" /> <a href="#cookie-merge"><code>Set-Cookie</code> header is - unmergeable</a></li> -<li><img alt="" src="../images/down.gif" /> <a href="#gif89-expires"><code>Expires</code> headers - and GIF89A animations</a></li> -<li><img alt="" src="../images/down.gif" /> <a href="#no-content-length"><code>POST</code> without - <code>Content-Length</code></a></li> -<li><img alt="" src="../images/down.gif" /> <a href="#jdk-12-bugs">JDK 1.2 betas lose - parts of responses.</a></li> -<li><img alt="" src="../images/down.gif" /> <a href="#content-type-persistent"><code>Content-Type</code> - change is not noticed after reload</a></li> -<li><img alt="" src="../images/down.gif" /> <a href="#msie-cookie-y2k">MSIE Cookie - problem with expiry date in the year 2000</a></li> -<li><img alt="" src="../images/down.gif" /> <a href="#lynx-negotiate-trans">Lynx incorrectly asking for - transparent content negotiation</a></li> -<li><img alt="" src="../images/down.gif" /> <a href="#ie40-vary">MSIE 4.0 mishandles Vary - response header</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="trailing-crlf" id="trailing-crlf">Trailing CRLF on POSTs</a></h2> - - <p>This is a legacy issue. The CERN webserver required - <code>POST</code> data to have an extra <code>CRLF</code> - following it. Thus many clients send an extra <code>CRLF</code> - that is not included in the <code>Content-Length</code> of the - request. Apache works around this problem by eating any empty - lines which appear before a request.</p> - - </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> -<div class="section"> -<h2><a name="broken-keepalive" id="broken-keepalive">Broken KeepAlive</a></h2> - - <p>Various clients have had broken implementations of - <em>keepalive</em> (persistent connections). In particular the - Windows versions of Navigator 2.0 get very confused when the - server times out an idle connection. The workaround is present - in the default config files:</p> - - <div class="example"><p><code> - BrowserMatch Mozilla/2 nokeepalive - </code></p></div> - - <p>Note that this matches some earlier versions of MSIE, which - began the practice of calling themselves <em>Mozilla</em> in - their user-agent strings just like Navigator.</p> - - <p>MSIE 4.0b2, which claims to support HTTP/1.1, does not - properly support keepalive when it is used on 301 or 302 - (redirect) responses. Unfortunately Apache's - <code>nokeepalive</code> code prior to 1.2.2 would not work - with HTTP/1.1 clients. You must apply <a href="http://www.apache.org/dist/httpd/patches/apply_to_1.2.1/msie_4_0b2_fixes.patch"> - this patch</a> to version 1.2.1. Then add this to your - config:</p> - - <div class="example"><p><code> - BrowserMatch "MSIE 4\.0b2;" nokeepalive - </code></p></div> - - </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> -<div class="section"> -<h2><a name="force-response-1.0" id="force-response-1.0">Incorrect interpretation of - <code>HTTP/1.1</code> in response</a></h2> - - <p>To quote from section 3.1 of RFC1945:</p> - - <div class="note"> - HTTP uses a "<MAJOR>.<MINOR>" numbering scheme to - indicate versions of the protocol. The protocol versioning - policy is intended to allow the sender to indicate the format - of a message and its capacity for understanding further HTTP - communication, rather than the features obtained via that - communication. - </div> - - <p>Since Apache is an HTTP/1.1 server, it indicates so as part of - its response. Many client authors mistakenly treat this part of - the response as an indication of the protocol that the response - is in, and then refuse to accept the response.</p> - - <p>The first major indication of this problem was with AOL's - proxy servers. When Apache 1.2 went into beta it was the first - wide-spread HTTP/1.1 server. After some discussion, AOL fixed - their proxies. In anticipation of similar problems, the - <code>force-response-1.0</code> environment variable was added - to Apache. When present Apache will indicate "HTTP/1.0" in - response to an HTTP/1.0 client, but will not in any other way - change the response.</p> - - <p>The pre-1.1 Java Development Kit (JDK) that is used in many - clients (including Navigator 3.x and MSIE 3.x) exhibits this - problem. As do some of the early pre-releases of the 1.1 JDK. - We think it is fixed in the 1.1 JDK release. In any event the - workaround:</p> - - <div class="example"><p><code> - BrowserMatch Java/1.0 force-response-1.0<br /> - BrowserMatch JDK/1.0 force-response-1.0 - </code></p></div> - - <p>RealPlayer 4.0 from Progressive Networks also exhibits this - problem. However they have fixed it in version 4.01 of the - player, but version 4.01 uses the same <code>User-Agent</code> - as version 4.0. The workaround is still:</p> - - <div class="example"><p><code> - BrowserMatch "RealPlayer 4.0" force-response-1.0 - </code></p></div> - - </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> -<div class="section"> -<h2><a name="msie4.0b2" id="msie4.0b2">Requests use HTTP/1.1 but - responses must be in HTTP/1.0</a></h2> - - <p>MSIE 4.0b2 has this problem. Its Java VM makes requests in - HTTP/1.1 format but the responses must be in HTTP/1.0 format - (in particular, it does not understand <em>chunked</em> - responses). The workaround is to fool Apache into believing the - request came in HTTP/1.0 format.</p> - - <div class="example"><p><code> - BrowserMatch "MSIE 4\.0b2;" downgrade-1.0 - force-response-1.0 - </code></p></div> - - <p>This workaround is available in 1.2.2, and in a <a href="http://www.apache.org/dist/httpd/patches/apply_to_1.2.1/msie_4_0b2_fixes.patch"> - patch</a> against 1.2.1.</p> - - </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> -<div class="section"> -<h2><a name="byte-257" id="byte-257">Boundary problems with - header parsing</a></h2> - - <p>All versions of Navigator from 2.0 through 4.0b2 (and - possibly later) have a problem if the trailing CRLF of the - response header starts at offset 256, 257 or 258 of the - response. A BrowserMatch for this would match on nearly every - hit, so the workaround is enabled automatically on all - responses. The workaround implemented detects when this - condition would occur in a response and adds extra padding to - the header to push the trailing CRLF past offset 258 of the - response.</p> - - </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> -<div class="section"> -<h2><a name="boundary-string" id="boundary-string">Multipart responses and - Quoted Boundary Strings</a></h2> - - <p>On multipart responses some clients will not accept quotes - (") around the boundary string. The MIME standard recommends - that such quotes be used. But the clients were probably written - based on one of the examples in RFC2068, which does not include - quotes. Apache does not include quotes on its boundary strings - to workaround this problem.</p> - - </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> -<div class="section"> -<h2><a name="byterange-requests" id="byterange-requests">Byterange Requests</a></h2> - - <p>A byterange request is used when the client wishes to - retrieve a portion of an object, not necessarily the entire - object. There was a very old draft which included these - byteranges in the URL. Old clients such as Navigator 2.0b1 and - MSIE 3.0 for the MAC exhibit this behaviour, and it will appear - in the servers' access logs as (failed) attempts to retrieve a - URL with a trailing ";xxx-yyy". Apache does not attempt to - implement this at all.</p> - - <p>A subsequent draft of this standard defines a header - <code>Request-Range</code>, and a response type - <code>multipart/x-byteranges</code>. The HTTP/1.1 standard - includes this draft with a few fixes, and it defines the header - <code>Range</code> and type - <code>multipart/byteranges</code>.</p> - - <p>Navigator (versions 2 and 3) sends both <code>Range</code> - and <code>Request-Range</code> headers (with the same value), - but does not accept a <code>multipart/byteranges</code> - response. The response must be - <code>multipart/x-byteranges</code>. As a workaround, if Apache - receives a <code>Request-Range</code> header it considers it - "higher priority" than a <code>Range</code> header and in - response uses <code>multipart/x-byteranges</code>.</p> - - <p>The Adobe Acrobat Reader plugin makes extensive use of - byteranges and prior to version 3.01 supports only the - <code>multipart/x-byterange</code> response. Unfortunately - there is no clue that it is the plugin making the request. If - the plugin is used with Navigator, the above workaround works - fine. But if the plugin is used with MSIE 3 (on Windows) the - workaround won't work because MSIE 3 doesn't give the - <code>Range-Request</code> clue that Navigator does. To - workaround this, Apache special cases "MSIE 3" in the - <code>User-Agent</code> and serves - <code>multipart/x-byteranges</code>. Note that the necessity - for this with MSIE 3 is actually due to the Acrobat plugin, not - due to the browser.</p> - - <p>Netscape Communicator appears to not issue the non-standard - <code>Request-Range</code> header. When an Acrobat plugin prior - to version 3.01 is used with it, it will not properly - understand byteranges. The user must upgrade their Acrobat - reader to 3.01.</p> - - </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> -<div class="section"> -<h2><a name="cookie-merge" id="cookie-merge"><code>Set-Cookie</code> header is - unmergeable</a></h2> - - <p>The HTTP specifications say that it is legal to merge - headers with duplicate names into one (separated by commas). - Some browsers that support Cookies don't like merged headers - and prefer that each <code>Set-Cookie</code> header is sent - separately. When parsing the headers returned by a CGI, Apache - will explicitly avoid merging any <code>Set-Cookie</code> - headers.</p> - - </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> -<div class="section"> -<h2><a name="gif89-expires" id="gif89-expires"><code>Expires</code> headers - and GIF89A animations</a></h2> - - <p>Navigator versions 2 through 4 will erroneously re-request - GIF89A animations on each loop of the animation if the first - response included an <code>Expires</code> header. This happens - regardless of how far in the future the expiry time is set. - There is no workaround supplied with Apache, however there are - hacks for <a href="http://www.arctic.org/~dgaudet/patches/apache-1.2-gif89-expires-hack.patch"> - 1.2</a> and for <a href="http://www.arctic.org/~dgaudet/patches/apache-1.3-gif89-expires-hack.patch"> - 1.3</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="no-content-length" id="no-content-length"><code>POST</code> without - <code>Content-Length</code></a></h2> - - <p>In certain situations Navigator 3.01 through 3.03 appear to - incorrectly issue a POST without the request body. There is no - known workaround. It has been fixed in Navigator 3.04, - Netscapes provides some <a href="http://help.netscape.com/kb/client/971014-42.html">information</a>. - There's also <a href="http://www.arctic.org/~dgaudet/apache/no-content-length/"> - some information</a> about the actual problem.</p> - - </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> -<div class="section"> -<h2><a name="jdk-12-bugs" id="jdk-12-bugs">JDK 1.2 betas lose - parts of responses.</a></h2> - - <p>The http client in the JDK1.2beta2 and beta3 will throw away - the first part of the response body when both the headers and - the first part of the body are sent in the same network packet - AND keep-alive's are being used. If either condition is not met - then it works fine.</p> - - <p>See also Bug-ID's 4124329 and 4125538 at the java developer - connection.</p> - - <p>If you are seeing this bug yourself, you can add the - following BrowserMatch directive to work around it:</p> - - <div class="example"><p><code> - BrowserMatch "Java1\.2beta[23]" nokeepalive - </code></p></div> - - <p>We don't advocate this though since bending over backwards - for beta software is usually not a good idea; ideally it gets - fixed, new betas or a final release comes out, and no one uses - the broken old software anymore. In theory.</p> - - </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> -<div class="section"> -<h2><a name="content-type-persistent" id="content-type-persistent"><code>Content-Type</code> - change is not noticed after reload</a></h2> - - <p>Navigator (all versions?) will cache the - <code>content-type</code> for an object "forever". Using reload - or shift-reload will not cause Navigator to notice a - <code>content-type</code> change. The only work-around is for - the user to flush their caches (memory and disk). By way of an - example, some folks may be using an old <code>mime.types</code> - file which does not map <code>.htm</code> to - <code>text/html</code>, in this case Apache will default to - sending <code>text/plain</code>. If the user requests the page - and it is served as <code>text/plain</code>. After the admin - fixes the server, the user will have to flush their caches - before the object will be shown with the correct - <code>text/html</code> type.</p> - - </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> -<div class="section"> -<h2><a name="msie-cookie-y2k" id="msie-cookie-y2k">MSIE Cookie - problem with expiry date in the year 2000</a></h2> - - <p>MSIE versions 3.00 and 3.02 (without the Y2K patch) do not - handle cookie expiry dates in the year 2000 properly. Years - after 2000 and before 2000 work fine. This is fixed in IE4.01 - service pack 1, and in the Y2K patch for IE3.02. Users should - avoid using expiry dates in the year 2000.</p> - - </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> -<div class="section"> -<h2><a name="lynx-negotiate-trans" id="lynx-negotiate-trans">Lynx incorrectly asking for - transparent content negotiation</a></h2> - - <p>The Lynx browser versions 2.7 and 2.8 send a "negotiate: - trans" header in their requests, which is an indication the - browser supports transparent content negotiation (TCN). However - the browser does not support TCN. As of version 1.3.4, Apache - supports TCN, and this causes problems with these versions of - Lynx. As a workaround future versions of Apache will ignore - this header when sent by the Lynx client.</p> - - </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> -<div class="section"> -<h2><a name="ie40-vary" id="ie40-vary">MSIE 4.0 mishandles Vary - response header</a></h2> - - <p>MSIE 4.0 does not handle a Vary header properly. The Vary - header is generated by mod_rewrite in apache 1.3. The result is - an error from MSIE saying it cannot download the requested - file. There are more details in <a href="http://bugs.apache.org/index/full/4118">PR#4118</a>.</p> - - <p>A workaround is to add the following to your server's - configuration files:</p> - - <div class="example"><p><code> - BrowserMatch "MSIE 4\.0" force-no-vary - </code></p></div> - - <p>(This workaround is only available with releases - <strong>after</strong> 1.3.6 of the Apache Web server.)</p> - - </div></div> -<div class="bottomlang"> -<p><span>Available Languages: </span><a href="../en/misc/known_client_problems.html" title="English"> en </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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