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Decryption trouble (Blowfish?).

felix fixanoid

Joined: Oct 21, 2009
Posts: 1
Hi! I'm hoping somebody here knows more about JCE and blowfish than me...

I get a remotely encrypted string: 53616c7465645f5f455ef6aa94807b56335681813d25923fc2790a11e152a9f7ecc72ad8641b84c438e63fdee2561ee6 -- which is supposed to be blowfish encryption in a hex string.
However, when I unhex it, I get another cryptic string:

Here is my unhexer:

Still, if I take that cryptic string and run through blowfish decryption, I get: javax.crypto.IllegalBlockSizeException: Input length must be multiple of 8 when decrypting with padded cipher

Any thoughts? Am I missing something essential? I've done this kind of encryption before tho I always relied on base64 encoded strings instead of hex/dehex....
greg stark
Ranch Hand

Joined: Aug 10, 2006
Posts: 220
You need to be working with byte [] arrays internally, not Strings. You can attempt to do the conversions yourself by modifying your unhexer method, or you can use someone else's class. I often recommend the apache commons codec package for this and similar operations. See the javadocs for the Hex class

Nice to meet you.
I agree. Here's the link:
subject: Decryption trouble (Blowfish?).
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