I took a look at the new cipher used in iTunes 4.7, and spent some time reducing it. The algorithm appears to have a similar structure to a 10-round Twofish variant with fixed S-boxes, optimized via precomputed tables. I have not fully analyzed what the permutation matrix and polynomial are, though.
There are a couple of strange changes. E.g., they had put the IV mixing between the pre-whitening and post-whitening, but this turned out to effectively cancel out and be equivalent to an altered version with a more traditional CBC structure. I'm including the current working implementation, along with some test vectors, if anyone else wants to take a look at it. --------------------------------------------------------------------- The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to [EMAIL PROTECTED]
