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 #include <string>
10 
ROTL32(uint32_t x,int8_t r)11 inline uint32_t ROTL32(uint32_t x, int8_t r)
12 {
13     return (x << r) | (x >> (32 - r));
14 }
15 
MurmurHash3(unsigned int nHashSeed,Span<const unsigned char> vDataToHash)16 unsigned int MurmurHash3(unsigned int nHashSeed, Span<const unsigned char> vDataToHash)
17 {
18     // The following is MurmurHash3 (x86_32), see http://code.google.com/p/smhasher/source/browse/trunk/MurmurHash3.cpp
19     uint32_t h1 = nHashSeed;
20     const uint32_t c1 = 0xcc9e2d51;
21     const uint32_t c2 = 0x1b873593;
22 
23     const int nblocks = vDataToHash.size() / 4;
24 
25     //----------
26     // body
27     const uint8_t* blocks = vDataToHash.data();
28 
29     for (int i = 0; i < nblocks; ++i) {
30         uint32_t k1 = ReadLE32(blocks + i*4);
31 
32         k1 *= c1;
33         k1 = ROTL32(k1, 15);
34         k1 *= c2;
35 
36         h1 ^= k1;
37         h1 = ROTL32(h1, 13);
38         h1 = h1 * 5 + 0xe6546b64;
39     }
40 
41     //----------
42     // tail
43     const uint8_t* tail = vDataToHash.data() + nblocks * 4;
44 
45     uint32_t k1 = 0;
46 
47     switch (vDataToHash.size() & 3) {
48         case 3:
49             k1 ^= tail[2] << 16;
50         case 2:
51             k1 ^= tail[1] << 8;
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 
BIP32Hash(const ChainCode & chainCode,unsigned int nChild,unsigned char header,const unsigned char data[32],unsigned char output[64])72 void BIP32Hash(const ChainCode &chainCode, unsigned int nChild, unsigned char header, const unsigned char data[32], unsigned char output[64])
73 {
74     unsigned char 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()).Write(&header, 1).Write(data, 32).Write(num, 4).Finalize(output);
80 }
81 
SHA256Uint256(const uint256 & input)82 uint256 SHA256Uint256(const uint256& input)
83 {
84     uint256 result;
85     CSHA256().Write(input.begin(), 32).Finalize(result.begin());
86     return result;
87 }
88 
TaggedHash(const std::string & tag)89 CHashWriter TaggedHash(const std::string& tag)
90 {
91     CHashWriter writer(SER_GETHASH, 0);
92     uint256 taghash;
93     CSHA256().Write((const unsigned char*)tag.data(), tag.size()).Finalize(taghash.begin());
94     writer << taghash << taghash;
95     return writer;
96 }
97