解決SELinux對網站目錄權限控制的不當的問題

前言：本文主要介紹了因為SELinux對網站目錄權限控制的不當而引起網站無法正常操作和訪問的問題。

正文開始：今天下午閒著沒有事做於是突然興起想嘗試安裝下Drupal。以前用Wordpress做博客久了，總想著嘗嘗新。

按照Installtion Guide提示的安裝步驟進行操作如下：

wget http://drupal.org/files/projects/drupal-7.12.tar.gz 
tar -zxvf drupal-7.12.tar.gz 
mv drupal-7.12 /var/www/html/home_start
cd /var/www/html/home_start
cp sites/default/default.settings.php sites/default/settings.php 
chmod a+w sites/default/settings.php 
chmod a+w sites/default 
mysqladmin -u username -p create databasename #用正確的字符串代替username和databasename

一切准備就緒！就等著進網站目錄進行下一步配置了！

不幸的是，在浏覽器中打開網站的目錄後就遭遇了httpd的403拒絕訪問提示。

這很顯然，根據以往的經驗可以判斷是目錄權限存在問題。

為了驗證這一說法，我們可以檢查httpd的錯誤日志。默認情況下日志就存在在/var/log/httpd/目錄中。

[root@localhost ~]# grep Permission /var/log/httpd/error_log 
[Tue Apr 10 09:07:04 2012] [error] [client 127.0.0.1] (13)Permission denied: access to /start denied 
[Tue Apr 10 09:07:50 2012] [error] [client 127.0.0.1] (13)Permission denied: access to /start/ denied 
[Tue Apr 10 09:08:07 2012] [error] [client 127.0.0.1] (13)Permission denied: access to /start/ denied 
[Tue Apr 10 09:10:06 2012] [error] [client 127.0.0.1] (13)Permission denied: access to /start/ denied 
[Tue Apr 10 09:11:08 2012] [error] [client 127.0.0.1] (13)Permission denied: access to /start/ denied 
[Tue Apr 10 09:11:17 2012] [error] [client 127.0.0.1] (13)Permission denied: access to /start denied 
[Tue Apr 10 09:11:34 2012] [error] [client ::1] (13)Permission denied: access to /start denied 
[Tue Apr 10 09:13:35 2012] [error] [client ::1] (13)Permission denied: access to /start denied 
[Tue Apr 10 09:13:51 2012] [error] [client ::1] (13)Permission denied: access to /start/site/default/ denied 
[Tue Apr 10 09:13:57 2012] [error] [client ::1] (13)Permission denied: access to /start/sites denied 
[Tue Apr 10 09:14:51 2012] [error] [client ::1] (13)Permission denied: access to /start/install.php denied 
[Tue Apr 10 09:18:57 2012] [error] [client ::1] (13)Permission denied: access to /start/install.php denied 
[Tue Apr 10 09:19:01 2012] [error] [client ::1] (13)Permission denied: access to /start/ denied 
[Tue Apr 10 09:22:03 2012] [error] [client ::1] (13)Permission denied: access to /start denied 
[Tue Apr 10 09:22:21 2012] [error] [client ::1] (13)Permission denied: access to /start denied 
[Tue Apr 10 09:22:24 2012] [error] [client ::1] (13)Permission denied: access to /start denied 
[Tue Apr 10 09:22:27 2012] [error] [client 127.0.0.1] (13)Permission denied: access to /start denied 
[Tue Apr 10 09:27:02 2012] [error] [client 127.0.0.1] (13)Permission denied: access to /start denied 
[Tue Apr 10 09:27:05 2012] [error] [client 127.0.0.1] (13)Permission denied: access to /start denied 
[Tue Apr 10 09:27:07 2012] [error] [client 127.0.0.1] (13)Permission denied: access to /start denied 
[Tue Apr 10 12:09:58 2012] [error] [client 127.0.0.1] (13)Permission denied: access to /home_start denied 
[Tue Apr 10 12:42:38 2012] [error] [client 127.0.0.1] (13)Permission denied: access to /home_start denied 
[Tue Apr 10 12:42:40 2012] [error] [client 127.0.0.1] (13)Permission denied: access to /home_start denied 
[Tue Apr 10 12:44:15 2012] [error] [client 127.0.0.1] (13)Permission denied: access to /home_start denied 
[Tue Apr 10 12:44:20 2012] [error] [client 127.0.0.1] (13)Permission denied: access to /home_start denied 
[Tue Apr 10 20:53:21 2012] [error] [client ::1] (13)Permission denied: access to /home_start denied 
[Tue Apr 10 21:07:21 2012] [error] [client ::1] (13)Permission denied: access to /home_start denied 
[Tue Apr 10 21:14:48 2012] [error] [client ::1] (13)Permission denied: access to /home_start denied 
[root@localhost ~]#  

再檢查網站目錄和文件的權限。為方便起見直接用-lZ選項。用於顯示詳細信息和SELinux權限信息

[root@localhost html]# ls -lZ 
-rw-r--r--. root root unconfined_u:object_r:httpd_sys_content_t:s0 archive.html 
drwxr-xr-x. root root unconfined_u:object_r:httpd_sys_content_t:s0 blog 
drwxr-xr-x. root root unconfined_u:object_r:httpd_sys_content_t:s0 blog_backup 
-rw-r--r--. root root unconfined_u:object_r:httpd_sys_content_t:s0 blog.htm 
-rw-r--r--. root root unconfined_u:object_r:httpd_sys_content_t:s0 blog.html 
drwxr-xr-x. root root unconfined_u:object_r:httpd_sys_content_t:s0 css 
drwxr-xr-x. root root unconfined_u:object_r:httpd_sys_content_t:s0 home_page 
drwxr-xr-x. root root unconfined_u:object_r:admin_home_t:s0 home_start #問題行
drwxr-xr-x. root root unconfined_u:object_r:httpd_sys_content_t:s0 images 
-rw-r--r--. root root unconfined_u:object_r:httpd_sys_content_t:s0 index.htm 
-rw-r--r--. root root unconfined_u:object_r:httpd_sys_content_t:s0 index.html 
-rw-r--r--. root root unconfined_u:object_r:httpd_sys_content_t:s0 info_php.php 
drwxr-xr-x. root root unconfined_u:object_r:httpd_sys_content_t:s0 js 
-rw-r--r--. root root unconfined_u:object_r:httpd_sys_content_t:s0 log 
drwxr-xr-x. root root unconfined_u:object_r:admin_home_t:s0 php #以前的遺留問題
drwxr-xr-x. root root unconfined_u:object_r:httpd_sys_content_t:s0 phpMyAdmin-3.4.10.1-all-languages 
drwxr-xr-x. root root unconfined_u:object_r:httpd_sys_content_t:s0 PSDs 
-rw-r--r--. root root unconfined_u:object_r:httpd_sys_content_t:s0 readme.txt 
-rw-r--r--. root root unconfined_u:object_r:httpd_sys_content_t:s0 style.htm 
-rw-r--r--. root root unconfined_u:object_r:httpd_sys_content_t:s0 style.html 
drwxr-xr-x. root root unconfined_u:object_r:httpd_sys_content_t:s0 wiki 

顯然上面顯示的結果中的09、16兩行的權限與其他網站目錄不同。

再查看selinx的工作狀態，判斷是不是SELinux引起的。

[root@localhost httpd]# sestatus  
SELinux status:                 enabled 
SELinuxfs mount:                /selinux 
Current mode:                   enforcing 
Mode from config file:          enforcing 
Policy version:                 24 
Policy from config file:        targeted 

這就是導致網站權限不正確的原因。

我猜測可能是在selinux啟用時對目錄或文件進行操作導致的。因為最近我對SELinux進行了升級（以前沒有遇到）。

所以使用chcon更改SELinux權限以及顯示結果如下：

setenforce 0 #必須暫時停止SELinux，否則可能導致操作失敗。 
chcon -t httpd_sys_content_t -R /var/www/html/home_start/ #R參數是遞歸操作的意思

經過修改就會發現SELinux的對應權限已經和其他目錄相同了！都是httpd_sys_content_t。

[root@localhost html]# setenforce --help 
usage:  setenforce [ Enforcing | Permissive | 1 | 0 ] 
[root@localhost html]# setenforce 0 
[root@localhost html]# cd 
[root@localhost ~]# ls /var/www/html/ -Z 
……
drwxr-xr-x. root root unconfined_u:object_r:admin_home_t:s0 home_start 
……
[root@localhost ~]# chcon -t httpd_sys_content_t -R /var/www/html/home_start/ 
[root@localhost ~]# ls /var/www/html/home_start/ -Z 
……
-rw-r--r--. root root unconfined_u:object_r:httpd_sys_content_t:s0 authorize.php 
……

然後，再次打開浏覽器輸入地址，驗證能否訪問，如果可以訪問就可以進行下一步配置了！

最後，還是那句話，遇到問題一定要仔細分析，盡可能的通過自己的努力和分析發現問題所在，這樣才能體會到解決問題的快樂！