( 12661, 0x5d84115du )
(143990, 0x9c592c78u )
(149000, 0x48f2bdc4u )
+ (160000, 0x789df0f0u )
;
// Hard checkpoints of stake modifiers to ensure they are deterministic (testNet)
bnTargetPerCoinDay.SetCompact(nBits);
int64_t nValueIn = pcoin.first->vout[pcoin.second].nValue;
- // Search backward in time from the given timestamp
+ // Search backward in time from the given timestamp
// Search nSearchInterval seconds back up to nMaxStakeSearchInterval
// Stopping search in case of shutting down or cache invalidation
for (unsigned int n=0; n<nCurrentSearchInterval && fCoinsDataActual && !fShutdown; n++)
return false;
}
+// Precompute hashing state for static part of kernel
+void GetKernelMidstate(uint64_t nStakeModifier, uint32_t nBlockTime, uint32_t nTxOffset, uint32_t nInputTxTime, uint32_t nOut, SHA256_CTX &ctx)
+{
+ // Build static part of kernel
+ CDataStream ssKernel(SER_GETHASH, 0);
+ ssKernel << nStakeModifier;
+ ssKernel << nBlockTime << nTxOffset << nInputTxTime << nOut;
+ CDataStream::const_iterator it = ssKernel.begin();
+
+ // Init sha256 context and update it
+ // with first 24 bytes of kernel
+ SHA256_Init(&ctx);
+ SHA256_Update(&ctx, (unsigned char*)&it[0], 8 + 16);
+}
+
+// Scan given midstate for solution
+bool ScanMidstateForward(SHA256_CTX &ctx, uint32_t nBits, uint32_t nInputTxTime, int64_t nValueIn, std::pair<uint32_t, uint32_t> &SearchInterval, std::pair<uint256, uint32_t> &solution)
+{
+ CBigNum bnTargetPerCoinDay;
+ bnTargetPerCoinDay.SetCompact(nBits);
+
+ // Get maximum possible target to filter out the majority of obviously insufficient hashes
+ CBigNum bnMaxTargetPerCoinDay = bnTargetPerCoinDay * CBigNum(nValueIn) * nStakeMaxAge / COIN / (24 * 60 * 60);
+ uint256 maxTarget = bnMaxTargetPerCoinDay.getuint256();
+
+ SHA256_CTX ctxCopy = ctx;
+
+ // Search forward in time from the given timestamp
+ // Stopping search in case of shutting down
+ for (uint32_t nTimeTx=SearchInterval.first; nTimeTx<SearchInterval.second && !fShutdown; nTimeTx++)
+ {
+ // Complete first hashing iteration
+ uint256 hash1;
+ SHA256_Update(&ctxCopy, (unsigned char*)&nTimeTx, 4);
+ SHA256_Final((unsigned char*)&hash1, &ctxCopy);
+
+ // Restore context
+ ctxCopy = ctx;
+
+ // Finally, calculate kernel hash
+ uint256 hashProofOfStake;
+ SHA256((unsigned char*)&hash1, sizeof(hashProofOfStake), (unsigned char*)&hashProofOfStake);
+
+ // Skip if hash doesn't satisfy the maximum target
+ if (hashProofOfStake > maxTarget)
+ continue;
+
+ CBigNum bnCoinDayWeight = CBigNum(nValueIn) * GetWeight((int64_t)nInputTxTime, (int64_t)nTimeTx) / COIN / (24 * 60 * 60);
+ CBigNum bnTargetProofOfStake = bnCoinDayWeight * bnTargetPerCoinDay;
+
+ if (bnTargetProofOfStake >= CBigNum(hashProofOfStake))
+ {
+ solution.first = hashProofOfStake;
+ solution.second = nTimeTx;
+
+ return true;
+ }
+ }
+
+ return false;
+}
+
// Check kernel hash target and coinstake signature
bool CheckProofOfStake(const CTransaction& tx, unsigned int nBits, uint256& hashProofOfStake, uint256& targetProofOfStake)
{