May 26, 2018
Perl extension for Apple iTMS internal key descrambling algorithm
This code appears to have only cursory resemblance to Bruce Schneier’s blowfish and twofish algorithms in that it too has a table-based decoder. Derivation from FairKeys code by Jon Lech Johanson at nanocrew.net. If you don’t know what that is, don’t bother looking here further. This is a Pure Perl implementation. I doubt there is any need for xs coding for what would mainly be processing 16 bytes at a time. This code is part of an ongoing effort to clone portions of the Apple iTMS in Perl for portability. See www.hymn-project.org for prior efforts by others.