Bitcoin Core  0.19.99
P2P Digital Currency
hash.cpp
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1 // Copyright (c) 2013-2018 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 #include <crypto/common.h>
7 #include <crypto/hmac_sha512.h>
8 
9 
10 inline uint32_t ROTL32(uint32_t x, int8_t r)
11 {
12  return (x << r) | (x >> (32 - r));
13 }
14 
15 unsigned int MurmurHash3(unsigned int nHashSeed, const std::vector<unsigned char>& vDataToHash)
16 {
17  // The following is MurmurHash3 (x86_32), see http://code.google.com/p/smhasher/source/browse/trunk/MurmurHash3.cpp
18  uint32_t h1 = nHashSeed;
19  const uint32_t c1 = 0xcc9e2d51;
20  const uint32_t c2 = 0x1b873593;
21 
22  const int nblocks = vDataToHash.size() / 4;
23 
24  //----------
25  // body
26  const uint8_t* blocks = vDataToHash.data();
27 
28  for (int i = 0; i < nblocks; ++i) {
29  uint32_t k1 = ReadLE32(blocks + i*4);
30 
31  k1 *= c1;
32  k1 = ROTL32(k1, 15);
33  k1 *= c2;
34 
35  h1 ^= k1;
36  h1 = ROTL32(h1, 13);
37  h1 = h1 * 5 + 0xe6546b64;
38  }
39 
40  //----------
41  // tail
42  const uint8_t* tail = vDataToHash.data() + nblocks * 4;
43 
44  uint32_t k1 = 0;
45 
46  switch (vDataToHash.size() & 3) {
47  case 3:
48  k1 ^= tail[2] << 16;
49  case 2:
50  k1 ^= tail[1] << 8;
51  case 1:
52  k1 ^= tail[0];
53  k1 *= c1;
54  k1 = ROTL32(k1, 15);
55  k1 *= c2;
56  h1 ^= k1;
57  }
58 
59  //----------
60  // finalization
61  h1 ^= vDataToHash.size();
62  h1 ^= h1 >> 16;
63  h1 *= 0x85ebca6b;
64  h1 ^= h1 >> 13;
65  h1 *= 0xc2b2ae35;
66  h1 ^= h1 >> 16;
67 
68  return h1;
69 }
70 
71 void BIP32Hash(const ChainCode &chainCode, unsigned int nChild, unsigned char header, const unsigned char data[32], unsigned char output[64])
72 {
73  unsigned char num[4];
74  num[0] = (nChild >> 24) & 0xFF;
75  num[1] = (nChild >> 16) & 0xFF;
76  num[2] = (nChild >> 8) & 0xFF;
77  num[3] = (nChild >> 0) & 0xFF;
78  CHMAC_SHA512(chainCode.begin(), chainCode.size()).Write(&header, 1).Write(data, 32).Write(num, 4).Finalize(output);
79 }
void Finalize(unsigned char hash[OUTPUT_SIZE])
Definition: hmac_sha512.cpp:29
CHMAC_SHA512 & Write(const unsigned char *data, size_t len)
Definition: hmac_sha512.h:24
unsigned char * begin()
Definition: uint256.h:54
unsigned int MurmurHash3(unsigned int nHashSeed, const std::vector< unsigned char > &vDataToHash)
Definition: hash.cpp:15
void BIP32Hash(const ChainCode &chainCode, unsigned int nChild, unsigned char header, const unsigned char data[32], unsigned char output[64])
Definition: hash.cpp:71
static const unsigned char k1[32]
unsigned int size() const
Definition: uint256.h:74
static uint32_t ReadLE32(const unsigned char *ptr)
Definition: common.h:24
256-bit opaque blob.
Definition: uint256.h:120
uint32_t ROTL32(uint32_t x, int8_t r)
Definition: hash.cpp:10
A hasher class for HMAC-SHA-512.
Definition: hmac_sha512.h:14