Encrypt with one cipher and decrypt with a different cipher?
I've checked out the source code (well, more or less, it's not that well designed, the main crypto class is 1600 lines) and as Richie guessed, the algorithm is stored together with the ciphertext.

Pretty gruesome stuff, but it does do EAX mode for text strings to my surprise. It probably only uses it for text strings originating from the password vault code though.

File encryption is performed in CBC mode. It does (ZIP) compress and stream files using CBC mode. It uses a static IV but this is offset by a random header that is included into the encryption.

This is a homegrown project with little documentation or comments in the code and a  slightly erratic class design.



Thanks go out to Tron to supply us the link to the format defition on the Paranoiaworks website.