为啥 apache2 试图执行我的 CSS 和图像文件？

Posted 2023-03-24

【中文标题】为啥 apache2 试图执行我的 CSS 和图像文件？

【英文标题】：Why is apache2 trying to execute my CSS and image files?为什么 apache2 试图执行我的 CSS 和图像文件？

【发布时间】：2021-09-27 01:11:53

【问题描述】：

我为此苦苦挣扎了两天，在网上搜索线索和答案，发现适用于 Mac 和 CGI​​ 脚本的内容很少。当我收到 500 错误时，可能有很多问题，但我认为它可能就像 apache2 试图执行我的非可执行文件一样简单，即 .css、.js、.png 等。我的配置文件（删除注释行）是这样的：

ServerRoot "/usr"

Listen 80

LoadModule authz_host_module libexec/apache2/mod_authz_host.so
LoadModule setenvif_module libexec/apache2/mod_setenvif.so
LoadModule mime_module libexec/apache2/mod_mime.so
LoadModule autoindex_module libexec/apache2/mod_autoindex.so
LoadModule cgi_module libexec/apache2/mod_cgi.so
LoadModule negotiation_module libexec/apache2/mod_negotiation.so
LoadModule userdir_module libexec/apache2/mod_userdir.so
LoadModule alias_module libexec/apache2/mod_alias.so

User _www
Group _www

ServerAdmin [e-mail]
DocumentRoot "/var/www"

<Directory />
        Options FollowSymLinks ExecCGI
        AllowOverride None
  </Directory>

<IfModule alias_module>
   ScriptAlias /cgi/ "/var/www/mywebsite/cgi/"
   AddHandler cgi-script .pl .cgi
      SetHandler cgi-script
</IfModule>

        <Directory /var/www/mywebsite/>
                Options +Indexes +FollowSymLinks -MultiViews 
                AllowOverride None
                Order allow,deny
                AddHandler cgi-script .cgi .pl
                allow from all
        </Directory>

        <Directory /var/www/mywebsite/*>
           AllowOverride AuthConfig
        </Directory>

        <Directory "/var/www/mywebsite/cgi/">
                AllowOverride None
                Options +ExecCGI -MultiViews +SymLinksIfOwnerMatch
                AddHandler cgi-script .cgi .pl
                Order allow,deny
                Allow from all
        </Directory>
        
<IfModule dir_module>
    DirectoryIndex index.html index.htm index.php
</IfModule>

ErrorLog "/private/var/log/apache2/error_log"
LogLevel warn

<IfModule log_config_module>
    LogFormat "%h %l %u %t \"%r\" %>s %b \"%Refereri\" \"%User-Agenti\"" combined
    LogFormat "%h %l %u %t \"%r\" %>s %b" common

    <IfModule logio_module>
      LogFormat "%h %l %u %t \"%r\" %>s %b \"%Refereri\" \"%User-Agenti\" %I %O" combinedio
    </IfModule>
    CustomLog "/private/var/log/apache2/access_log" common
</IfModule>

DefaultType text/plain

<IfModule mime_module>
    TypesConfig /private/etc/apache2/mime.types
    AddType application/x-compress .Z
    AddType application/x-gzip .gz .tgz
</IfModule>

TraceEnable off

当我尝试加载我的页面时，Perl 脚本运行，但是嵌入到它提供给浏览器的 HTML 中的链接都出现 http 500 错误（或者如果我从基本目录中删除了“ExecCGI”，则会出现 403 错误选项）。

这是页面加载后日志文件显示的内容：

[Mon Jul 19 17:37:59 2021] [error] [client ::1] (8)Exec format error: exec of '/var/www/css/MW.css' failed, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:37:59 2021] [error] [client ::1] Premature end of script headers: MW.css, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:37:59 2021] [error] [client ::1] (13)Permission denied: exec of '/var/www/css/new.gif' failed, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:37:59 2021] [error] [client ::1] Premature end of script headers: new.gif, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:37:59 2021] [error] [client ::1] (13)Permission denied: exec of '/var/www/css/MW_lang_LA.png' failed, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:37:59 2021] [error] [client ::1] Premature end of script headers: MW_lang_LA.png, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:37:59 2021] [error] [client ::1] (13)Permission denied: exec of '/var/www/css/MW_lang_US.png' failed, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:37:59 2021] [error] [client ::1] Premature end of script headers: MW_lang_US.png, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:37:59 2021] [error] [client ::1] (13)Permission denied: exec of '/var/www/css/MW.js' failed, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:37:59 2021] [error] [client ::1] Premature end of script headers: MW.js, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:37:59 2021] [error] [client ::1] (13)Permission denied: exec of '/var/www/css/MW_lang_TH.png' failed, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:37:59 2021] [error] [client ::1] Premature end of script headers: MW_lang_TH.png, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:37:59 2021] [error] [client ::1] (13)Permission denied: exec of '/var/www/css/MW_lang_VT.png' failed, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:37:59 2021] [error] [client ::1] Premature end of script headers: MW_lang_VT.png, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:37:59 2021] [error] [client ::1] (13)Permission denied: exec of '/var/www/css/MW_lang_SP.png' failed, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:37:59 2021] [error] [client ::1] Premature end of script headers: MW_lang_SP.png, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:38:01 2021] [error] [client ::1] (8)Exec format error: exec of '/var/www/css/MW.css' failed, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:38:01 2021] [error] [client ::1] Premature end of script headers: MW.css, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:38:01 2021] [error] [client ::1] (13)Permission denied: exec of '/var/www/css/MW_lang_US.png' failed, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:38:01 2021] [error] [client ::1] Premature end of script headers: MW_lang_US.png, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:38:01 2021] [error] [client ::1] (13)Permission denied: exec of '/var/www/css/MW_lang_TH.png' failed, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:38:01 2021] [error] [client ::1] Premature end of script headers: MW_lang_TH.png, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:38:01 2021] [error] [client ::1] (13)Permission denied: exec of '/var/www/css/MW.js' failed, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:38:01 2021] [error] [client ::1] Premature end of script headers: MW.js, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:38:01 2021] [error] [client ::1] (13)Permission denied: exec of '/var/www/css/MW_lang_LA.png' failed, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:38:01 2021] [error] [client ::1] Premature end of script headers: MW_lang_LA.png, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:38:01 2021] [error] [client ::1] (13)Permission denied: exec of '/var/www/css/MW_lang_SP.png' failed, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:38:01 2021] [error] [client ::1] Premature end of script headers: MW_lang_SP.png, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:38:01 2021] [error] [client ::1] (13)Permission denied: exec of '/var/www/css/MW_lang_VT.png' failed, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:38:01 2021] [error] [client ::1] Premature end of script headers: MW_lang_VT.png, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:38:01 2021] [error] [client ::1] (13)Permission denied: exec of '/var/www/css/new.gif' failed, referer: http://localhost/mywebsite/cgi/MW.pl
[Mon Jul 19 17:38:01 2021] [error] [client ::1] Premature end of script headers: new.gif, referer: http://localhost/mywebsite/cgi/MW.pl

如图所示，即使是图像文件也被视为需要执行的脚本！自然会遇到语法错误。

更多信息：

Mac OS X：10.8.3 Apache 服务器版本：Apache/2.2.22 (Unix) Apache 服务器构建时间：2012 年 12 月 9 日 18:57:18 火狐：48.0.2 image/css/js 文件的文件权限都设置为 chmod 644

Apache 仅在本地托管网站——这不是互联网虚拟主机。这应该是供离线使用和开发目的。

为什么 apache2 会这样做？配置有什么问题？

【参考方案1】：

嗯，这看起来有点狡猾。

<Directory />
    Options FollowSymLinks ExecCGI
    AllowOverride None
</Directory>

首先，这会将您的整个文件系统（/ 下的所有内容）视为 Web 服务器的一部分。其次，您为 Apache 服务的每个文件都打开了 ExecCGI - 这会导致您的问题。

您还将实际的 CGI 目录 (/var/www/mywebsite/cgi/) 定义为 CGI 目录两次。

【讨论】：

感谢您的帮助。我现在已经完全删除了 /var/www/mywebsite/cgi 目录定义，只留下了对该 cgi 目录的 ScriptAlias 引用，并且我删除了四个“狡猾”的行，而且奇怪的是，结果根本看不到任何变化。还有什么我可以做的吗？

我现在实际上已经从配置中删除了“ExecCGI”的每个实例，只在 ScriptAlias 行下留下了“AddHandler cgi-script .pl .cgi”——这似乎足以保留perl 脚本正在运行。

终于发现了问题所在，把答案贴出来留给后人。谢谢你鼓励我多尝试一些东西——几乎放弃了。

【参考方案2】：

反复试验（猜测和检查）终于让我找到了答案。这是配置文件中有问题的一行。我现在没有删除该行，而是用一条注释对其进行了评论，以提醒我永远不要再使用该行！

AddHandler cgi-script .pl .cgi

# ENABLING THE FOLLOWING LINE WILL MAKE _EVERY_ FILE EXECUTE!!!
#      SetHandler cgi-script      

SetHandler cgi-script 纯属毒药。我永远不会猜到——它看起来如此无害和天真，甚至是必要的。

没有这条线，一切都会再次按预期工作。图像、css 和 js 文件的 http 响应 200 现在看起来非常漂亮！

【讨论】：

根据httpd.apache.org/docs/2.2/handler.html，SetHandler 通常应该设置在Directory 或Location 块内，但你的是/曾经是***的，所以也许这就是它应用的原因到所有文件？我没想到会有这种行为，所以很好地追踪它！