From ba5da0946c3abaa93d1161ca512c3c326cda3736 Mon Sep 17 00:00:00 2001 From: Mounir IDRASSI Date: Fri, 8 Feb 2019 01:48:12 +0100 Subject: Windows: Add implementation of ChaCha20 based random generator. Use it for driver need of random bytes (currently only wipe bytes but more to come later). --- src/Crypto/chachaRng.h | 63 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 63 insertions(+) create mode 100644 src/Crypto/chachaRng.h (limited to 'src/Crypto/chachaRng.h') diff --git a/src/Crypto/chachaRng.h b/src/Crypto/chachaRng.h new file mode 100644 index 00000000..a2cb4ce8 --- /dev/null +++ b/src/Crypto/chachaRng.h @@ -0,0 +1,63 @@ +/* $OpenBSD: arc4random.c,v 1.54 2015/09/13 08:31:47 guenther Exp $ */ + +/* + * Copyright (c) 1996, David Mazieres + * Copyright (c) 2008, Damien Miller + * Copyright (c) 2013, Markus Friedl + * Copyright (c) 2014, Theo de Raadt + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +/* + * ChaCha based random number generator for OpenBSD. + */ + +/* + * Adapted for VeraCrypt + */ + +#ifndef HEADER_Crypto_ChaChaRng +#define HEADER_Crypto_ChaChaRng + +#include "chacha256.h" + +#define CHACHA20RNG_KEYSZ 32 +#define CHACHA20RNG_IVSZ 8 +#define CHACHA20RNG_BLOCKSZ 64 +#define CHACHA20RNG_RSBUFSZ (16*CHACHA20RNG_BLOCKSZ) + +#ifdef __cplusplus +extern "C" { +#endif + +typedef void (*GetRandSeedFn)(unsigned char* pbRandSeed, size_t cbRandSeed); + +typedef struct +{ + ChaCha256Ctx m_chachaCtx; /* ChaCha20 context */ + unsigned char m_rs_buf[CHACHA20RNG_RSBUFSZ]; /* keystream blocks */ + size_t m_rs_have; /* valid bytes at end of rs_buf */ + size_t m_rs_count; /* bytes till reseed */ + GetRandSeedFn m_getRandSeedCallback; +} ChaCha20RngCtx; + +/* key length must be equal to 40 bytes (CHACHA20RNG_KEYSZ + CHACHA20RNG_IVSZ) */ +void ChaCha20RngInit (ChaCha20RngCtx* pCtx, const unsigned char* key, GetRandSeedFn rngCallback, size_t InitialBytesToSkip); +void ChaCha20RngGetBytes (ChaCha20RngCtx* pCtx, unsigned char* buffer, size_t bufferLen); + +#ifdef __cplusplus +} +#endif + +#endif -- cgit v1.2.3