Supported elliptic curves:
NIST Curves: P-256, P-384, P-521
Unsupported elliptic curves:
NIST Curves: B-283, B-409, B-57 are not supported – patent concerns. Alternate curves not supported: M-221, E-222, Curve1174, Curve25519, E-382, M-383, Curve383187, Curve41417, Ed448-Goldilocks, M-511, and E-521.