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Diffstat (limited to 'src/testrand_impl.h')
-rw-r--r-- | src/testrand_impl.h | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/src/testrand_impl.h b/src/testrand_impl.h new file mode 100644 index 0000000000..677c4b9a0e --- /dev/null +++ b/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" + +static uint32_t secp256k1_Rz = 11, secp256k1_Rw = 11; + +SECP256K1_INLINE static void secp256k1_rand_seed(uint64_t v) { + secp256k1_Rz = v >> 32; + secp256k1_Rw = v; + + if (secp256k1_Rz == 0 || secp256k1_Rz == 0x9068ffffU) { + secp256k1_Rz = 111; + } + if (secp256k1_Rw == 0 || secp256k1_Rw == 0x464fffffU) { + secp256k1_Rw = 111; + } +} + +SECP256K1_INLINE static uint32_t secp256k1_rand32(void) { + secp256k1_Rz = 36969 * (secp256k1_Rz & 0xFFFF) + (secp256k1_Rz >> 16); + secp256k1_Rw = 18000 * (secp256k1_Rw & 0xFFFF) + (secp256k1_Rw >> 16); + return (secp256k1_Rw << 16) + (secp256k1_Rw >> 16) + secp256k1_Rz; +} + +static void secp256k1_rand256(unsigned char *b32) { + for (int i=0; i<8; i++) { + uint32_t r = secp256k1_rand32(); + b32[i*4 + 0] = (r >> 0) & 0xFF; + b32[i*4 + 1] = (r >> 8) & 0xFF; + b32[i*4 + 2] = (r >> 16) & 0xFF; + b32[i*4 + 3] = (r >> 24) & 0xFF; + } +} + +static void secp256k1_rand256_test(unsigned char *b32) { + int bits=0; + memset(b32, 0, 32); + while (bits < 256) { + uint32_t ent = secp256k1_rand32(); + int now = 1 + ((ent % 64)*((ent >> 6) % 32)+16)/31; + uint32_t val = 1 & (ent >> 11); + while (now > 0 && bits < 256) { + b32[bits / 8] |= val << (bits % 8); + now--; + bits++; + } + } +} + +#endif |