[openpgp] Ed25519
Werner Koch <wk@gnupg.org> Thu, 14 November 2013 17:55 UTC
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From: Werner Koch <wk@gnupg.org>
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Date: Thu, 14 Nov 2013 18:47:02 +0100
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Subject: [openpgp] Ed25519
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Hi, a few weeks ago I already mentioned that I would like to implement Ed25519 in GnuPG. Meanwhile I did that but I am not sure whether we really want this hack. Ed25519 is based on Curve25519 but uses a different signature algorithm than EdDSA. That algorithm avoids a lot of pitfalls using plain ECDSA. The paper [1] explains this in detail. I implemented that by switching to this algorithm for a certain OID. It does not look right to do so. Thus I wonder whether we better assign a new id for EdDSA. I have not yet seen the specs for Curve3617 but I assume that it uses a similar scheme for signing. Thus Ed25519 and a signing algorithm for Curve3617 may share the same algorithm id. Or well, for an even more compact key format we could also directly assign an algorithm id for Ed25519. A separate algorithm id would also allow to use the compressed key format instead of packing it into the 0x04 uncompressed format as specified by rfc-6637. A problem I see in writing an I-D is that there is no formal specification of Ed25519, just the paper. I am not sure whether is acceptable for an RFC. The next free algorithm id would be 22. Shalom-Salam, Werner [1] See http://ed25519.cr.yp.to/ -- Die Gedanken sind frei. Ausnahmen regelt ein Bundesgesetz.
- [openpgp] Ed25519 Werner Koch