1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2021 The FreeBSD Foundation 5 * 6 * This software was developed by Ararat River Consulting, LLC under 7 * sponsorship from the FreeBSD Foundation. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 */ 30 31 #ifndef __CRYPTO_CURVE25519_H__ 32 #define __CRYPTO_CURVE25519_H__ 33 34 #include <sys/libkern.h> 35 36 #define CURVE25519_KEY_SIZE 32 37 38 bool curve25519(uint8_t *public, const uint8_t *secret, 39 const uint8_t *basepoint); 40 bool curve25519_generate_public(uint8_t *public, 41 const uint8_t *secret); 42 43 static __inline void 44 curve25519_clamp_secret(uint8_t *secret) 45 { 46 secret[0] &= 248; 47 secret[31] &= 127; 48 secret[31] |= 64; 49 } 50 51 static __inline void 52 curve25519_generate_secret(uint8_t *secret) 53 { 54 arc4random_buf(secret, CURVE25519_KEY_SIZE); 55 curve25519_clamp_secret(secret); 56 } 57 58 #endif /* __CRYPTO_CURVE25519_H__ */ 59