Question

Is it possible to encrypt (and concatenate) two strings in mod rewrite without calling an external program? If not, then which is the fastest multi platform solution for that?

I’m thinking on creating a token from the session id, and a static salt, and check it by file download. So the statics files would be only accessible with the correct session id and token. (sharing the token would not be enough…)

Answer 1

Nope its not possible through mod_rewrite:

Apache Module mod_rewrite

mod_rewrite provides a way to modify incoming URL requests, dynamically, based on regular expression rules. This allows you to map arbitrary URLs onto your internal URL structure in any way you like.

I do not know which programming language you are using:
You can use Blowfish implementation for your language. Since its quite popular I suspect there should be one available.

I’m thinking on creating a token from the session id, and a static salt,:
It looks like you are looking for a One way Hash function rather than an encryption.