RFR CSR for 8213400: Support choosing curve name in keytool keypair generation

[Weijun Wang]

Please take a review at the CSR at

   https://bugs.openjdk.java.net/browse/JDK-8213401

As for implementation, I intend to report an error when -keyalg is not EC but -curvename is provided. If both -curvename and -keysize are provided, I intend to ignore -keysize no matter if they match or not.

Another question: in sun.security.util.CurveDB, we have

    // Return EC parameters for the specified field size. If there are known
    // NIST recommended parameters for the given length, they are returned.
    // Otherwise, if there are multiple matches for the given size, an
    // arbitrary one is returns.
    // If no parameters are known, the method returns null.
    // NOTE that this method returns both prime and binary curves.
    static NamedCurve lookup(int length) {
        return lengthMap.get(length);
    }

FIPS 186-4 has 2 recommendations (K- and B-) for a binary curve field size. Do we have a choice?

In fact, CurveDB.java seems to have a bug when adding the curves:

    add("sect163k1 [NIST K-163]", "1.3.132.0.1", BD,...
    add("sect163r2 [NIST B-163]", "1.3.132.0.15", BD,... // Another default?
    add("sect233k1 [NIST K-233]", "1.3.132.0.26", BD,...
    add("sect233r1 [NIST B-233]", "1.3.132.0.27", B,...

and now 163 is sect163r2 and 233 is sect233k1.

I assume we should always prefer the K- one?

Thanks
Max