Thursday, April 1, 2010

htaccess Cheatsheet

SkyHi @ Thursday, April 01, 2010
Here is a simple cheatsheet for the .htaccess file:
Enable Directory Browsing
Options +Indexes
## block a few types of files from showing
IndexIgnore *.wmv *.mp4 *.avi
Disable Directory Browsing
Options All -Indexes
Customize Error Messages
ErrorDocument 403 /forbidden.html
ErrorDocument 404 /notfound.html
ErrorDocument 500 /servererror.html
Get SSI working with HTML/SHTML
AddType text/html .html
AddType text/html .shtml
AddHandler server-parsed .html
AddHandler server-parsed .shtml
# AddHandler server-parsed .htm
Change Default Page (order is followed!)
DirectoryIndex myhome.htm index.htm index.php
Block Users from accessing the site

order deny,allow
deny from
deny from
deny from
allow from all
Allow only LAN users
order deny,allow
deny from all
allow from
Redirect Visitors to New Page/Directory
Redirect oldpage.html
Redirect /olddir
Block site from specific referrers
RewriteEngine on
RewriteCond %{HTTP_REFERER} site-to-block\.com [NC]
RewriteCond %{HTTP_REFERER} site-to-block-2\.com [NC]
RewriteRule .* - [F]
Block Hot Linking/Bandwidth hogging
RewriteEngine on
RewriteCond %{HTTP_REFERER} !^$
RewriteCond %{HTTP_REFERER} !^http://(www\.)?*$ [NC]
RewriteRule \.(gif|jpg)$ - [F]
Want to show a “Stealing is Bad” message too?
Add this below the Hot Link Blocking code:
RewriteRule \.(gif|jpg)$ [R,L]
Stop .htaccess (or any other file) from being viewed

order allow,deny
deny from all
Avoid the 500 Error
# Avoid 500 error by passing charset
AddDefaultCharset utf-8
Grant CGI Access in a directory
Options +ExecCGI
AddHandler cgi-script cgi pl
# To enable all scripts in a directory use the following
# SetHandler cgi-script
Password Protecting Directories
Use the .htaccess Password Generator and follow the brief instructions!
Change Script Extensions
AddType application/x-httpd-php .gne
gne will now be treated as PHP files! Similarly, x-httpd-cgi for CGI files, etc.
Use MD5 Digests
Performance may take a hit but if thats not a problem, this is a nice option to turn on.
ContentDigest On
The CheckSpelling Directive
From Jens Meiert: CheckSpelling corrects simple spelling errors (for example, if someone forgets a letter or if any character is just wrong). Just add CheckSpelling On to your htaccess file.
The ContentDigest Directive
As the Apache core features documentation says: “This directive enables the generation of Content-MD5 headers as defined in RFC1864 respectively RFC2068. The Content-MD5 header provides an end-to-end message integrity check (MIC) of the entity-body. A proxy or client may check this header for detecting accidental modification of the entity-body in transit.
Note that this can cause performance problems on your server since the message digest is computed on every request (the values are not cached). Content-MD5 is only sent for documents served by the core, and not by any module. For example, SSI documents, output from CGI scripts, and byte range responses do not have this header.”
To turn this on, just add ContentDigest On.
Enable Gzip – Save Bandwidth

# Combine the below two lines - I've split it up for presentation
AddOutputFilterByType DEFLATE text/text text/html text/plain text/xml text/css
  application/x-javascript application/javascript
Turn off magic_quotes_gpc
# Only if you use PHP

php_flag magic_quotes_gpc off
Set an Expires header and enable Cache-Control

  ExpiresActive On
  ExpiresDefault "access plus 1 seconds"
  ExpiresByType text/html "access plus 7200 seconds"
  ExpiresByType image/gif "access plus 518400 seconds"
  ExpiresByType image/jpeg "access plus 518400 seconds"
  ExpiresByType image/png "access plus 518400 seconds"
  ExpiresByType text/css "access plus 518400 seconds"
  ExpiresByType text/javascript "access plus 216000 seconds"
  ExpiresByType application/x-javascript "access plus 216000 seconds"

  # Cache specified files for 6 days
  Header set Cache-Control "max-age=518400, public"
  # Cache HTML files for a couple hours
  Header set Cache-Control "max-age=7200, private, must-revalidate"
  # Cache PDFs for a day
  Header set Cache-Control "max-age=86400, public"
  # Cache Javascripts for 2.5 days
  Header set Cache-Control "max-age=216000, private"