| 1 | /* SPDX-License-Identifier: GPL-2.0 OR MIT */ |
|---|---|
| 2 | /* |
| 3 | * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved. |
| 4 | */ |
| 5 | |
| 6 | #ifndef CURVE25519_H |
| 7 | #define CURVE25519_H |
| 8 | |
| 9 | #include <linux/types.h> |
| 10 | #include <linux/random.h> |
| 11 | |
| 12 | enum curve25519_lengths { |
| 13 | CURVE25519_KEY_SIZE = 32 |
| 14 | }; |
| 15 | |
| 16 | void curve25519_generic(u8 out[at_least CURVE25519_KEY_SIZE], |
| 17 | const u8 scalar[at_least CURVE25519_KEY_SIZE], |
| 18 | const u8 point[at_least CURVE25519_KEY_SIZE]); |
| 19 | |
| 20 | bool __must_check |
| 21 | curve25519(u8 mypublic[at_least CURVE25519_KEY_SIZE], |
| 22 | const u8 secret[at_least CURVE25519_KEY_SIZE], |
| 23 | const u8 basepoint[at_least CURVE25519_KEY_SIZE]); |
| 24 | |
| 25 | bool __must_check |
| 26 | curve25519_generate_public(u8 pub[at_least CURVE25519_KEY_SIZE], |
| 27 | const u8 secret[at_least CURVE25519_KEY_SIZE]); |
| 28 | |
| 29 | static inline void |
| 30 | curve25519_clamp_secret(u8 secret[at_least CURVE25519_KEY_SIZE]) |
| 31 | { |
| 32 | secret[0] &= 248; |
| 33 | secret[31] = (secret[31] & 127) | 64; |
| 34 | } |
| 35 | |
| 36 | static inline void |
| 37 | curve25519_generate_secret(u8 secret[at_least CURVE25519_KEY_SIZE]) |
| 38 | { |
| 39 | get_random_bytes_wait(buf: secret, nbytes: CURVE25519_KEY_SIZE); |
| 40 | curve25519_clamp_secret(secret); |
| 41 | } |
| 42 | |
| 43 | #endif /* CURVE25519_H */ |
| 44 |