src/hash.h

   1 // Copyright (c) 2009-2010 Satoshi Nakamoto
   2 // Copyright (c) 2009-2015 The Bitcoin Core developers
   3 // Distributed under the MIT software license, see the accompanying
   4 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
   5
   6 #ifndef BITCOIN_HASH_H
   7 #define BITCOIN_HASH_H
   8
   9 #include "crypto/ripemd160.h"
  10 #include "crypto/sha256.h"
  11 #include "prevector.h"
  12 #include "serialize.h"
  13 #include "uint256.h"
  14 #include "version.h"
  15
  16 #include <vector>
  17
  18 typedef uint256 ChainCode;
  19
  20 /** A hasher class for Bitcoin's 256-bit hash (double SHA-256). */
  21 class CHash256 {
  22 private:
  23     CSHA256 sha;
  24 public:
  25     static const size_t OUTPUT_SIZE = CSHA256::OUTPUT_SIZE;
  26
  27     void Finalize(unsigned char hash[OUTPUT_SIZE]) {
  28         unsigned char buf[sha.OUTPUT_SIZE];
  29         sha.Finalize(buf);
  30         sha.Reset().Write(buf, sha.OUTPUT_SIZE).Finalize(hash);
  31     }
  32
  33     CHash256& Write(const unsigned char *data, size_t len) {
  34         sha.Write(data, len);
  35         return *this;
  36     }
  37
  38     CHash256& Reset() {
  39         sha.Reset();
  40         return *this;
  41     }
  42 };
  43
  44 /** A hasher class for Bitcoin's 160-bit hash (SHA-256 + RIPEMD-160). */
  45 class CHash160 {
  46 private:
  47     CSHA256 sha;
  48 public:
  49     static const size_t OUTPUT_SIZE = CRIPEMD160::OUTPUT_SIZE;
  50
  51     void Finalize(unsigned char hash[OUTPUT_SIZE]) {
  52         unsigned char buf[sha.OUTPUT_SIZE];
  53         sha.Finalize(buf);
  54         CRIPEMD160().Write(buf, sha.OUTPUT_SIZE).Finalize(hash);
  55     }
  56
  57     CHash160& Write(const unsigned char *data, size_t len) {
  58         sha.Write(data, len);
  59         return *this;
  60     }
  61
  62     CHash160& Reset() {
  63         sha.Reset();
  64         return *this;
  65     }
  66 };
  67
  68 /** Compute the 256-bit hash of an object. */
  69 template<typename T1>
  70 inline uint256 Hash(const T1 pbegin, const T1 pend)
  71 {
  72     static const unsigned char pblank[1] = {};
  73     uint256 result;
  74     CHash256().Write(pbegin == pend ? pblank : (const unsigned char*)&pbegin[0], (pend - pbegin) * sizeof(pbegin[0]))
  75               .Finalize((unsigned char*)&result);
  76     return result;
  77 }
  78
  79 /** Compute the 256-bit hash of the concatenation of two objects. */
  80 template<typename T1, typename T2>
  81 inline uint256 Hash(const T1 p1begin, const T1 p1end,
  82                     const T2 p2begin, const T2 p2end) {
  83     static const unsigned char pblank[1] = {};
  84     uint256 result;
  85     CHash256().Write(p1begin == p1end ? pblank : (const unsigned char*)&p1begin[0], (p1end - p1begin) * sizeof(p1begin[0]))
  86               .Write(p2begin == p2end ? pblank : (const unsigned char*)&p2begin[0], (p2end - p2begin) * sizeof(p2begin[0]))
  87               .Finalize((unsigned char*)&result);
  88     return result;
  89 }
  90
  91 /** Compute the 256-bit hash of the concatenation of three objects. */
  92 template<typename T1, typename T2, typename T3>
  93 inline uint256 Hash(const T1 p1begin, const T1 p1end,
  94                     const T2 p2begin, const T2 p2end,
  95                     const T3 p3begin, const T3 p3end) {
  96     static const unsigned char pblank[1] = {};
  97     uint256 result;
  98     CHash256().Write(p1begin == p1end ? pblank : (const unsigned char*)&p1begin[0], (p1end - p1begin) * sizeof(p1begin[0]))
  99               .Write(p2begin == p2end ? pblank : (const unsigned char*)&p2begin[0], (p2end - p2begin) * sizeof(p2begin[0]))
 100               .Write(p3begin == p3end ? pblank : (const unsigned char*)&p3begin[0], (p3end - p3begin) * sizeof(p3begin[0]))
 101               .Finalize((unsigned char*)&result);
 102     return result;
 103 }
 104
 105 /** Compute the 160-bit hash an object. */
 106 template<typename T1>
 107 inline uint160 Hash160(const T1 pbegin, const T1 pend)
 108 {
 109     static unsigned char pblank[1] = {};
 110     uint160 result;
 111     CHash160().Write(pbegin == pend ? pblank : (const unsigned char*)&pbegin[0], (pend - pbegin) * sizeof(pbegin[0]))
 112               .Finalize((unsigned char*)&result);
 113     return result;
 114 }
 115
 116 /** Compute the 160-bit hash of a vector. */
 117 inline uint160 Hash160(const std::vector<unsigned char>& vch)
 118 {
 119     return Hash160(vch.begin(), vch.end());
 120 }
 121
 122 /** Compute the 160-bit hash of a vector. */
 123 template<unsigned int N>
 124 inline uint160 Hash160(const prevector<N, unsigned char>& vch)
 125 {
 126     return Hash160(vch.begin(), vch.end());
 127 }
 128
 129 /** A writer stream (for serialization) that computes a 256-bit hash. */
 130 class CHashWriter
 131 {
 132 private:
 133     CHash256 ctx;
 134
 135 public:
 136     int nType;
 137     int nVersion;
 138
 139     CHashWriter(int nTypeIn, int nVersionIn) : nType(nTypeIn), nVersion(nVersionIn) {}
 140
 141     CHashWriter& write(const char *pch, size_t size) {
 142         ctx.Write((const unsigned char*)pch, size);
 143         return (*this);
 144     }
 145
 146     // invalidates the object
 147     uint256 GetHash() {
 148         uint256 result;
 149         ctx.Finalize((unsigned char*)&result);
 150         return result;
 151     }
 152
 153     template<typename T>
 154     CHashWriter& operator<<(const T& obj) {
 155         // Serialize to this stream
 156         ::Serialize(*this, obj, nType, nVersion);
 157         return (*this);
 158     }
 159 };
 160
 161 /** Compute the 256-bit hash of an object's serialization. */
 162 template<typename T>
 163 uint256 SerializeHash(const T& obj, int nType=SER_GETHASH, int nVersion=PROTOCOL_VERSION)
 164 {
 165     CHashWriter ss(nType, nVersion);
 166     ss << obj;
 167     return ss.GetHash();
 168 }
 169
 170 unsigned int MurmurHash3(unsigned int nHashSeed, const std::vector<unsigned char>& vDataToHash);
 171
 172 void BIP32Hash(const ChainCode &chainCode, unsigned int nChild, unsigned char header, const unsigned char data[32], unsigned char output[64]);
 173
 174 #endif // BITCOIN_HASH_H