XTR cryptosystem

Werner Koch wk at gnupg.org
Mon Feb 24 14:35:02 CET 2003

On Mon, 24 Feb 2003 12:03:23 +0100, ecesena at libero it said:

> I'm studying XTR cryptosystem (www.ecstr.com) for my thesis and I'd like to implement XTR support for GPG as an "exercise".

XTR is patented and as such useless.  Quite some time ago, I contacted
Lenstra and the Citibank to ask about the licensing conditions and
whether they consider to give a perpetual royality free license like
some other companies did with their crypto algorithms (e.g. CAST5) -
the answer was no.

> Then I'll implement the code in xtrelgamal.c... 
> but then?

Register them in cipher/pubkey.c.  You also need to assign an OpenPGP
identifier: 101 - 110 is reserved for experimental use; use one in
this range.



More information about the Gnupg-devel mailing list