diff options
Diffstat (limited to 'crypto/secp256k1/libsecp256k1/src/testrand_impl.h')
-rw-r--r-- | crypto/secp256k1/libsecp256k1/src/testrand_impl.h | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/crypto/secp256k1/libsecp256k1/src/testrand_impl.h b/crypto/secp256k1/libsecp256k1/src/testrand_impl.h new file mode 100644 index 000000000..7c3554266 --- /dev/null +++ b/crypto/secp256k1/libsecp256k1/src/testrand_impl.h @@ -0,0 +1,60 @@ +/********************************************************************** + * Copyright (c) 2013, 2014 Pieter Wuille * + * Distributed under the MIT software license, see the accompanying * + * file COPYING or http://www.opensource.org/licenses/mit-license.php.* + **********************************************************************/ + +#ifndef _SECP256K1_TESTRAND_IMPL_H_ +#define _SECP256K1_TESTRAND_IMPL_H_ + +#include <stdint.h> +#include <string.h> + +#include "testrand.h" +#include "hash.h" + +static secp256k1_rfc6979_hmac_sha256_t secp256k1_test_rng; +static uint32_t secp256k1_test_rng_precomputed[8]; +static int secp256k1_test_rng_precomputed_used = 8; + +SECP256K1_INLINE static void secp256k1_rand_seed(const unsigned char *seed16) { + secp256k1_rfc6979_hmac_sha256_initialize(&secp256k1_test_rng, seed16, 16); +} + +SECP256K1_INLINE static uint32_t secp256k1_rand32(void) { + if (secp256k1_test_rng_precomputed_used == 8) { + secp256k1_rfc6979_hmac_sha256_generate(&secp256k1_test_rng, (unsigned char*)(&secp256k1_test_rng_precomputed[0]), sizeof(secp256k1_test_rng_precomputed)); + secp256k1_test_rng_precomputed_used = 0; + } + return secp256k1_test_rng_precomputed[secp256k1_test_rng_precomputed_used++]; +} + +static void secp256k1_rand256(unsigned char *b32) { + secp256k1_rfc6979_hmac_sha256_generate(&secp256k1_test_rng, b32, 32); +} + +static void secp256k1_rand256_test(unsigned char *b32) { + int bits=0; + uint64_t ent = 0; + int entleft = 0; + memset(b32, 0, 32); + while (bits < 256) { + int now; + uint32_t val; + if (entleft < 12) { + ent |= ((uint64_t)secp256k1_rand32()) << entleft; + entleft += 32; + } + now = 1 + ((ent % 64)*((ent >> 6) % 32)+16)/31; + val = 1 & (ent >> 11); + ent >>= 12; + entleft -= 12; + while (now > 0 && bits < 256) { + b32[bits / 8] |= val << (bits % 8); + now--; + bits++; + } + } +} + +#endif |