So I did some digging and Certicom claims nothing against RFC 6090. They do claim 2 patents against the draft, but I doubt either of them check out. One is on point validation by substitution into a curve, the other on ECDSA for smart cards. If its a big worry Tor should get a lawyer to check this out, but I'm not that worried: Patents filled in the 2000s seem a bit late to the party anyway. Sincerely, Watson Ladd On Tue, Nov 1, 2011 at 2:05 PM, Zooko O'Whielacronx <zooko@zooko.com> wrote:

A few pointers. On the happy "yay we can use it freely" side, we have:

* RFC 6090

Pure gold! A catalog of ECC techniques which were published so long ago that they cannot still be under patent. It includes digital signatures and Diffie-Hellman.

* DJB's page stating that certain patents don't apply to Curve25519 (which you mentioned): http://cr.yp.to/ecdh/patents.html

* Jack Lloyd's statement that he avoided techniques newer than about 1990 in Botan: https://bugzilla.redhat.com/show_bug.cgi?id=615372#c19

On the sad "no we can't use it" side, we have:

* Fedora's insistence on removing all elliptic curve cryptography from their Linux distribution and refusing to answer questions about why: https://bugzilla.redhat.com/show_bug.cgi?id=615372

Regards,

Zooko _______________________________________________ tor-dev mailing list tor-dev@lists.torproject.org https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev

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