On Thu, May 23, 2019 at 6:54 PM Wim Lewis wiml@hhhh.org wrote:
On Thursday, May 23, 2019 1:41:47 PM PDT, Niels Möller wrote:
...
For the details, it's good to have a specific reference to follow. There'a also been a feature request to convert points to and from ANSI x9.62, possibly related? Maybe converting to and from octest strings according to some specification is more useful as an advertised interface, than x coordinate + sign (not ruling out having both).
Related, one sharp edge with SEC.1 is, the the private key has the same length as order of the curve. That means, for example, a secp160 private key is 21 bytes instead of 20 bytes.
I've seen bug reports because of the difference.
The private key length was supposed to change to order of base point in a future version of SEC, but I did not see the change in SEC-2.
Also, I have a copy of x9.62 if you need something copied. I don't have a copy of P1363, though.
Jeff