Re: [Curdle] State of draft-ietf-curdle-ssh-kex-sha2?
Peter Gutmann <[email protected]> Tue, 14 Jul 2020 04:10:18 +0000
| Newsgroups | gmane.ietf.secsh |
|---|---|
| Message-ID | <[email protected]> |
Mouse <[email protected]> writes: >As an implementor, it is highly unlikely I will support anything elliptic >curve in the foreseeable future. I support it but it's disabled by default because I can't think of a commonly- used cryptosystem more riddled with side-channels than (EC)DSA, and most of them end up leaking the private key (that's ECDSA, not 25519 which is too novel/nonstandard to be usable with anything I work with). In fact a recent paper on yet another set of side-channel attacks (either "Minerva: The Curse of ECDSA Nonces" or "Big Numbers - Big Troubles") mentions that this is merely the latest set of side-channels that need patching, and more are expected in the future. And that's after several years of patching ECDSA side-channels already. At least with RSA you can just blind and be mostly done with it, you don't have to deal with a mechanism where there's a linear relation between the signing nonce and the private key, with everything around that tied up in side-channels. Peter.