1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2019 Conrad Meyer <cem@FreeBSD.org> 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 * 27 * $FreeBSD$ 28 */ 29 #pragma once 30 31 #include <crypto/chacha20/chacha.h> 32 #include <dev/random/fenestrasX/fx_priv.h> 33 34 #define FX_CHACHA20_KEYSIZE 32 35 36 struct fxrng_basic_rng { 37 struct mtx rng_lk; 38 #define FXRNG_RNG_LOCK(rng) mtx_lock(&(rng)->rng_lk) 39 #define FXRNG_RNG_UNLOCK(rng) mtx_unlock(&(rng)->rng_lk) 40 #define FXRNG_RNG_ASSERT(rng) mtx_assert(&(rng)->rng_lk, MA_OWNED) 41 #define FXRNG_RNG_ASSERT_NOT(rng) mtx_assert(&(rng)->rng_lk, MA_NOTOWNED) 42 /* CTR-mode cipher state, including 128-bit embedded counter. */ 43 struct chacha_ctx rng_prf; 44 }; 45 46 /* 47 * Initialize a basic rng instance (half of a buffered FX BRNG). 48 * Memory should be zero initialized before this routine. 49 */ 50 static inline void 51 fxrng_rng_init(struct fxrng_basic_rng *rng, bool is_root_rng) 52 { 53 if (is_root_rng) 54 mtx_init(&rng->rng_lk, "fx root brng lk", NULL, MTX_DEF); 55 else 56 mtx_init(&rng->rng_lk, "fx pcpu brng lk", NULL, MTX_DEF); 57 } 58 59 static inline void 60 fxrng_rng_setkey(struct fxrng_basic_rng *rng, const void *newkey, size_t len) 61 { 62 ASSERT_DEBUG(len == FX_CHACHA20_KEYSIZE, "chacha20 uses 256 bit keys"); 63 chacha_keysetup(&rng->rng_prf, newkey, len * 8); 64 } 65 66 void fxrng_rng_genrandom_internal(struct fxrng_basic_rng *, void *, size_t, 67 bool return_unlocked); 68 69 void fxrng_rng_reseed(struct fxrng_basic_rng *, bool seeded, const void *, 70 size_t); 71 void fxrng_rng_src_reseed(struct fxrng_basic_rng *, 72 const struct harvest_event *); 73