Bitcoin ABC  0.22.12
P2P Digital Currency
hash.cpp
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1 // Copyright (c) 2013-2016 The Bitcoin Core developers
2 // Distributed under the MIT software license, see the accompanying
3 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
4 
5 #include <hash.h>
6 
7 #include <crypto/hmac_sha512.h>
8 
9 inline uint32_t ROTL32(uint32_t x, int8_t r) {
10  return (x << r) | (x >> (32 - r));
11 }
12 
13 uint32_t MurmurHash3(uint32_t nHashSeed,
14  const std::vector<uint8_t> &vDataToHash) {
15  // The following is MurmurHash3 (x86_32), see
16  // http://code.google.com/p/smhasher/source/browse/trunk/MurmurHash3.cpp
17  uint32_t h1 = nHashSeed;
18  const uint32_t c1 = 0xcc9e2d51;
19  const uint32_t c2 = 0x1b873593;
20 
21  const int nblocks = vDataToHash.size() / 4;
22 
23  //----------
24  // body
25  const uint8_t *blocks = vDataToHash.data();
26 
27  for (int i = 0; i < nblocks; ++i) {
28  uint32_t k1 = ReadLE32(blocks + i * 4);
29 
30  k1 *= c1;
31  k1 = ROTL32(k1, 15);
32  k1 *= c2;
33 
34  h1 ^= k1;
35  h1 = ROTL32(h1, 13);
36  h1 = h1 * 5 + 0xe6546b64;
37  }
38 
39  //----------
40  // tail
41  const uint8_t *tail = vDataToHash.data() + nblocks * 4;
42 
43  uint32_t k1 = 0;
44 
45  switch (vDataToHash.size() & 3) {
46  case 3:
47  k1 ^= tail[2] << 16;
48  // FALLTHROUGH
49  case 2:
50  k1 ^= tail[1] << 8;
51  // FALLTHROUGH
52  case 1:
53  k1 ^= tail[0];
54  k1 *= c1;
55  k1 = ROTL32(k1, 15);
56  k1 *= c2;
57  h1 ^= k1;
58  }
59 
60  //----------
61  // finalization
62  h1 ^= vDataToHash.size();
63  h1 ^= h1 >> 16;
64  h1 *= 0x85ebca6b;
65  h1 ^= h1 >> 13;
66  h1 *= 0xc2b2ae35;
67  h1 ^= h1 >> 16;
68 
69  return h1;
70 }
71 
72 void BIP32Hash(const ChainCode &chainCode, uint32_t nChild, uint8_t header,
73  const uint8_t data[32], uint8_t output[64]) {
74  uint8_t num[4];
75  num[0] = (nChild >> 24) & 0xFF;
76  num[1] = (nChild >> 16) & 0xFF;
77  num[2] = (nChild >> 8) & 0xFF;
78  num[3] = (nChild >> 0) & 0xFF;
79  CHMAC_SHA512(chainCode.begin(), chainCode.size())
80  .Write(&header, 1)
81  .Write(data, 32)
82  .Write(num, 4)
83  .Finalize(output);
84 }
uint32_t MurmurHash3(uint32_t nHashSeed, const std::vector< uint8_t > &vDataToHash)
Definition: hash.cpp:13
void BIP32Hash(const ChainCode &chainCode, uint32_t nChild, uint8_t header, const uint8_t data[32], uint8_t output[64])
Definition: hash.cpp:72
uint8_t * begin()
Definition: uint256.h:76
unsigned int size() const
Definition: uint256.h:84
static uint32_t ReadLE32(const uint8_t *ptr)
Definition: common.h:23
static const uint8_t k1[32]
256-bit opaque blob.
Definition: uint256.h:120
void Finalize(uint8_t hash[OUTPUT_SIZE])
Definition: hmac_sha512.cpp:30
uint32_t ROTL32(uint32_t x, int8_t r)
Definition: hash.cpp:9
CHMAC_SHA512 & Write(const uint8_t *data, size_t len)
Definition: hmac_sha512.h:23
A hasher class for HMAC-SHA-512.
Definition: hmac_sha512.h:14