Static ring::agreement::ECDH_P256

pub static ECDH_P256: Algorithm = agreement::Algorithm{i:
                         ec::AgreementAlgorithmImpl{public_key_len:
                                                        1 + 2 * 256 + 7 / 8,
                                                    elem_and_scalar_len:
                                                        256 + 7 / 8,
                                                    nid: 415,
                                                    generate_private_key:
                                                        p256_generate_private_key,
                                                    public_from_private:
                                                        p256_public_from_private,
                                                    ecdh: p256_ecdh,},}

ECDH using the NSA Suite B P-256 (secp256r1) curve.

Public keys are encoding in uncompressed form using the Octet-String-to-Elliptic-Curve-Point algorithm in SEC 1: Elliptic Curve Cryptography, Version 2.0. Public keys are validated during key agreement according to NIST Special Publication 800-56A, revision 2 and Appendix B.3 of the NSA's Suite B Implementer's Guide to NIST SP 800-56A.