Line data    Source code

       1             : /**
       2             :  * @file       CoinSpend.cpp
       3             :  *
       4             :  * @brief      CoinSpend class for the Zerocoin library.
       5             :  *
       6             :  * @author     Ian Miers, Christina Garman and Matthew Green
       7             :  * @date       June 2013
       8             :  *
       9             :  * @copyright  Copyright 2013 Ian Miers, Christina Garman and Matthew Green
      10             :  * @license    This project is released under the MIT license.
      11             :  **/
      12             : // Copyright (c) 2017-2021 The PIVX Core developers
      13             : 
      14             : #include "CoinSpend.h"
      15             : #include <iostream>
      16             : #include <sstream>
      17             : 
      18             : namespace libzerocoin
      19             : {
      20             : 
      21           0 : const uint256 CoinSpend::signatureHash() const
      22             : {
      23           0 :     CHashWriter h(0, 0);
      24           0 :     h << serialCommitmentToCoinValue << accCommitmentToCoinValue << commitmentPoK << accumulatorPoK << ptxHash
      25           0 :       << coinSerialNumber << accChecksum << denomination;
      26             : 
      27           0 :     if (version >= PUBKEY_VERSION)
      28           0 :         h << spendType;
      29             : 
      30           0 :     return h.GetHash();
      31             : }
      32             : 
      33           0 : std::string CoinSpend::ToString() const
      34             : {
      35           0 :     std::stringstream ss;
      36           0 :     ss << "CoinSpend:\n version=" << (int)version << " signatureHash=" << signatureHash().GetHex() << " spendtype=" << spendType << "\n";
      37           0 :     return ss.str();
      38             : }
      39             : 
      40           0 : bool CoinSpend::HasValidSerial(ZerocoinParams* params) const
      41             : {
      42           0 :     return IsValidSerial(params, coinSerialNumber);
      43             : }
      44             : 
      45             : //Additional verification layer that requires the spend be signed by the private key associated with the serial
      46           0 : bool CoinSpend::HasValidSignature() const
      47             : {
      48           0 :     const int coinVersion = getCoinVersion();
      49             :     //No private key for V1
      50           0 :     if (coinVersion < PUBKEY_VERSION)
      51             :         return true;
      52             : 
      53           0 :     try {
      54             :         //V2 serial requires that the signature hash be signed by the public key associated with the serial
      55           0 :         arith_uint256 hashedPubkey = UintToArith256(Hash(pubkey.begin(), pubkey.end())) >> V2_BITSHIFT;
      56           0 :         if (hashedPubkey != GetAdjustedSerial(coinSerialNumber).getuint256()) {
      57             :             //cout << "CoinSpend::HasValidSignature() hashedpubkey is not equal to the serial!\n";
      58           0 :             return false;
      59             :         }
      60           0 :     } catch (const std::range_error& e) {
      61             :         //std::cout << "HasValidSignature() error: " << e.what() << std::endl;
      62           0 :         throw InvalidSerialException("Serial longer than 256 bits");
      63             :     }
      64             : 
      65           0 :     return pubkey.Verify(signatureHash(), vchSig);
      66             : }
      67             : 
      68           0 : CBigNum CoinSpend::CalculateValidSerial(ZerocoinParams* params)
      69             : {
      70           0 :     CBigNum bnSerial = coinSerialNumber;
      71           0 :     bnSerial = bnSerial % params->coinCommitmentGroup.groupOrder;
      72           0 :     return bnSerial;
      73             : }
      74             : 
      75           0 : std::vector<unsigned char> CoinSpend::ParseSerial(CDataStream& s) {
      76           0 :     unsigned int nSize = ReadCompactSize(s);
      77           0 :     s.movePos(nSize);
      78           0 :     nSize = ReadCompactSize(s);
      79           0 :     s.movePos(nSize);
      80           0 :     CBigNum coinSerialNumber;
      81           0 :     s >> coinSerialNumber;
      82           0 :     return coinSerialNumber.getvch();
      83             : }
      84             : 
      85           0 : void CoinSpend::setPubKey(CPubKey pkey, bool fUpdateSerial) {
      86           0 :     this->pubkey = pkey;
      87           0 :     if (fUpdateSerial) {
      88           0 :         this->coinSerialNumber = libzerocoin::ExtractSerialFromPubKey(this->pubkey);
      89             :     }
      90           0 : }
      91             : 
      92             : } /* namespace libzerocoin */