1 /* SPDX-License-Identifier: GPL-2.0 OR MIT */
2 /*
3  * Copyright (C) 2015-2020 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
4  */
5 
6 #ifndef CURVE25519_H
7 #define CURVE25519_H
8 
9 #include <stdint.h>
10 #include <sys/types.h>
11 
12 enum curve25519_lengths {
13 	CURVE25519_KEY_SIZE = 32
14 };
15 
16 void curve25519(uint8_t mypublic[static CURVE25519_KEY_SIZE], const uint8_t secret[static CURVE25519_KEY_SIZE], const uint8_t basepoint[static CURVE25519_KEY_SIZE]);
17 void curve25519_generate_public(uint8_t pub[static CURVE25519_KEY_SIZE], const uint8_t secret[static CURVE25519_KEY_SIZE]);
18 static inline void curve25519_clamp_secret(uint8_t secret[static CURVE25519_KEY_SIZE])
19 {
20 	secret[0] &= 248;
21 	secret[31] = (secret[31] & 127) | 64;
22 }
23 
24 #endif
25