in reply to Crypt::RC5 128-bit?

1) If I use the same key and same number of rounds, should the output ciphertext from the 32-bit RC5 = ciphertext from the 128-bit RC5?

No. Even if it would come out the same after a single round, the 128-bit version probably goes through a lot more rounds than the 32-bit version.

Does anybody know of any 128-bit implementations in Perl for RC5?

Not sure on this. The Crypt::RC5 module has a few places in it that look like you could just do an s/32/128/g and s/31/127/g, but I would hesitate to try without having my copy of Applied Crypto nearby.

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I wanted to explore how Perl's closures can be manipulated, and ended up creating an object system by accident.
-- Schemer

:(){ :|:&};:

Note: All code is untested, unless otherwise stated