On Mon, 2018-03-12 at 20:56 +0100, Stephan Mueller wrote: > Am Montag, 12. März 2018, 19:09:18 CET schrieb James Bottomley: > > Hi James, > > > > > On Mon, 2018-03-12 at 19:07 +0200, Tudor Ambarus wrote: > > > > > > Hi, > > > > > > Would you consider using ECDSA in the kernel module signing > > > facility? When compared with RSA, ECDSA has shorter keys, the key > > > generation process is faster, the sign operation is faster, but > > > the verify operation is slower than with RSA. > > > > You missed the keyrings list, which is where the module signing > > utility is discussed. > > > > First question is, have you actually tried? It looks like sign- > > file doesn't do anything RSA specific so if you give it an EC X.509 > > certificate it will produce an ECDSA signature. > > > > I think our kernel internal x509 parsers don't have the EC OIDs, so > > signature verification will fail; but, especially since we have the > > rest of the EC machinery in the crypto subsystem, that looks to be > > simply fixable. > > ECDSA is not implemented currently in the kernel crypto API. an ECDSA signature is produced as a ECDH operation using the DSA algorithm instead of KDFe, so it's trivial with what we have; signature verification involves a separate point addition but we have all the primitives for this in crypto/ecc.c so adding it isn't really difficult, is it? James
