1// Copyright 2015-2017 Brian Smith.
2//
3// Permission to use, copy, modify, and/or distribute this software for any
4// purpose with or without fee is hereby granted, provided that the above
5// copyright notice and this permission notice appear in all copies.
6//
7// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHORS DISCLAIM ALL WARRANTIES
8// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
9// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
10// SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
11// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
12// OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
13// CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
14
15use crate::{cpu, ec, error, rand};
16
17/// A key agreement algorithm.
18macro_rules! suite_b_curve {
19 ( $NAME:ident, $bits:expr, $private_key_ops:expr, $id:expr,
20 $check_private_key_bytes:ident, $generate_private_key:ident,
21 $public_from_private:ident) => {
22 /// Public keys are encoding in uncompressed form using the
23 /// Octet-String-to-Elliptic-Curve-Point algorithm in
24 /// [SEC 1: Elliptic Curve Cryptography, Version 2.0]. Public keys are
25 /// validated during key agreement according to
26 /// [NIST Special Publication 800-56A, revision 2] and Appendix B.3 of
27 /// the NSA's [Suite B Implementer's Guide to NIST SP 800-56A].
28 ///
29 /// [SEC 1: Elliptic Curve Cryptography, Version 2.0]:
30 /// http://www.secg.org/sec1-v2.pdf
31 /// [NIST Special Publication 800-56A, revision 2]:
32 /// http://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-56Ar2.pdf
33 /// [Suite B Implementer's Guide to NIST SP 800-56A]:
34 /// https://github.com/briansmith/ring/blob/main/doc/ecdh.pdf
35 pub static $NAME: ec::Curve = ec::Curve {
36 public_key_len: 1 + (2 * (($bits + 7) / 8)),
37 elem_scalar_seed_len: ($bits + 7) / 8,
38 id: $id,
39 check_private_key_bytes: $check_private_key_bytes,
40 generate_private_key: $generate_private_key,
41 public_from_private: $public_from_private,
42 };
43
44 fn $check_private_key_bytes(
45 bytes: &[u8],
46 cpu: cpu::Features,
47 ) -> Result<(), error::Unspecified> {
48 debug_assert_eq!(bytes.len(), $bits / 8);
49 ec::suite_b::private_key::check_scalar_big_endian_bytes($private_key_ops, bytes, cpu)
50 }
51
52 fn $generate_private_key(
53 rng: &dyn rand::SecureRandom,
54 out: &mut [u8],
55 cpu: cpu::Features,
56 ) -> Result<(), error::Unspecified> {
57 ec::suite_b::private_key::generate_private_scalar_bytes($private_key_ops, rng, out, cpu)
58 }
59
60 fn $public_from_private(
61 public_out: &mut [u8],
62 private_key: &ec::Seed,
63 cpu: cpu::Features,
64 ) -> Result<(), error::Unspecified> {
65 ec::suite_b::private_key::public_from_private(
66 $private_key_ops,
67 public_out,
68 private_key,
69 cpu,
70 )
71 }
72 };
73}
74
75suite_b_curve!(
76 P256,
77 256,
78 &ec::suite_b::ops::p256::PRIVATE_KEY_OPS,
79 ec::CurveID::P256,
80 p256_check_private_key_bytes,
81 p256_generate_private_key,
82 p256_public_from_private
83);
84
85suite_b_curve!(
86 P384,
87 384,
88 &ec::suite_b::ops::p384::PRIVATE_KEY_OPS,
89 ec::CurveID::P384,
90 p384_check_private_key_bytes,
91 p384_generate_private_key,
92 p384_public_from_private
93);
94