Limiting access to one directory when on subdomain

Howdy, I need to do the following:

• allow access to sub.domain.com/directory from www.domain.com (linking to an asset)
• prevent access to sub.domain.com/* (Return a 404 page when开发者_开发知识库 user hits subdomain directly

Is this possible using htaccess and, if so, any pointers on how to accomplish it?

Thanks

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Using .htaccess you might want to look up htaccess and regex tutorials as they are of great help.

Stop sites from hotlinking is what I assume you are referring to therefore: you need to enable mod_rewrite and add this to the .htaccess file in the domain's root directory (with a little of what you learn):

RewriteEngine On
RewriteCond %{HTTP_REFERER} !^http://(.+\.)?domain\.com/ [NC]
RewriteCond %{HTTP_REFERER} !^$
RewriteRule .*\.(jpe?g|gif|bmp|png)$ http://www.domain.com/noHotlink.gif

This should point you in the right direction towards how to do it.