[Hero]

Hi
This is one of the question that is asked too much.But I should say that attacking
to a rar or any other compressing ways theoricaly has no way except Bruteforce or
dictionary attack(If it developed well such as rar and zip).
Because algorithm is too simple,You add a signature in for example start of file and then
encrypt all the file.When you want to decrypt it,after decoding some blocks of file if the
signature was wrong that means you enter the password wrong and in this way there
is no need for saving password in file and attacking to it is similar to attacking an encryption
algorithm(It is a way that can be used,I didn't know rar or zip algorithms but they should
be similar).

sincerely yours