What are the best practices for handling permissions and access control when using mod_rewrite in PHP?

When using mod_rewrite in PHP, it is important to handle permissions and access control properly to ensure the security of your application. One best practice is to restrict access to certain directories or files by using RewriteCond directives to check for specific conditions before allowing the rewrite to occur.

RewriteEngine On

# Check if the request is for a specific directory
RewriteCond %{REQUEST_URI} ^/admin/
# Check if the user is authenticated
RewriteCond %{HTTP_COOKIE} !^.*authenticated=true.*$
# Redirect to a login page if not authenticated
RewriteRule ^(.*)$ /login.php [L]

# Allow access to other directories or files
RewriteRule ^(.*)$ index.php [L]