map<COutPoint, CInPoint> mapNextTx;
map<uint256, CBlockIndex*> mapBlockIndex;
+set<COutPoint> setStakeSeen;
uint256 hashGenesisBlock("0x000000006d52486334316794cc38ffeb7ebf35a7ebd661fd39f5f46b0d001575");
static CBigNum bnProofOfWorkLimit(~uint256(0) >> 32);
const int nInitialBlockThreshold = 120; // Regard blocks up until N-threshold as "initial download"
// Check for negative or overflow output values
int64 nValueOut = 0;
- for (int i = (IsCoinStake()? 1 : 0); i < vout.size(); i++)
+ for (int i = 0; i < vout.size(); i++)
{
const CTxOut& txout = vout[i];
+ if (txout.IsEmpty() && (!IsCoinBase()) && (!IsCoinStake()))
+ return DoS(100, error("CTransaction::CheckTransaction() : txout empty for user transaction"));
if (txout.nValue < 0)
return DoS(100, error("CTransaction::CheckTransaction() : txout.nValue negative"));
if (txout.nValue > MAX_MONEY)
// ppcoin: target change every block
// ppcoin: retarget with exponential moving toward target spacing
CBigNum bnNew;
- bnNew.SetCompact(pindexLast->nBits);
+ bnNew.SetCompact(pindexPrev->nBits);
bnNew *= ((nInterval - 1) * nTargetSpacing + nActualSpacing + nActualSpacing);
bnNew /= ((nInterval + 1) * nTargetSpacing);
// ppcoin: fees are not collected by miners as in bitcoin
// ppcoin: fees are destroyed to compensate the entire network
- if (vtx[0].GetValueOut() > GetProofOfWorkReward(nBits))
+ if (IsProofOfWork() && vtx[0].GetValueOut() > GetProofOfWorkReward(nBits))
return false;
if (fDebug && GetBoolArg("-printcreation"))
printf("ConnectBlock() : destroy=%s nFees=%"PRI64d"\n", FormatMoney(nFees).c_str(), nFees);
// ppcoin: coinstake must meet hash target according to the protocol:
// at least one input must meet the formula
-// hash(nBits + txPrev.block.nTime + txPrev.nTime + nTime) < bnTarget * nCoinDay
+// hash(nBits + txPrev.block.nTime + txPrev.offset + txPrev.nTime + txPrev.vout.n + nTime) < bnTarget * nCoinDay
// this ensures that the chance of getting a coinstake is proportional to the
// amount of coin age one owns.
// The reason this hash is chosen is the following:
-// nBits: encodes all past block timestamps, prevents computing hash in advance
-// txPrev.block.nTime: prevent nodes from guessing a good timestamp to generate
-// transaction for future advantage
-// txPrev.nTime: prevent nodes from meeting target simultaneously
-// block/tx hash should not be used here as they can be generated in vast quatities
-// so as to generate blocks faster, degrading the system back into a proof-of-work
-// situation.
+// nBits: encodes all past block timestamps, making computing hash in advance
+// more difficult
+// txPrev.block.nTime: prevent nodes from guessing a good timestamp to
+// generate transaction for future advantage
+// txPrev.offset: offset of txPrev inside block, to reduce the chance of
+// nodes generating coinstake at the same time
+// txPrev.nTime: reduce the chance of nodes generating coinstake at the same
+// time
+// txPrev.vout.n: output number of txPrev, to reduce the chance of nodes
+// generating coinstake at the same time
+// block/tx hash should not be used here as they can be generated in vast
+// quantities so as to generate blocks faster, degrading the system back into
+// a proof-of-work situation.
//
bool CTransaction::CheckProofOfStake(CTxDB& txdb, unsigned int nBits) const
{
if (!IsCoinStake())
return true;
- BOOST_FOREACH(const CTxIn& txin, vin)
- {
- // First try finding the previous transaction in database
- CTransaction txPrev;
- CTxIndex txindex;
- if (!txPrev.ReadFromDisk(txdb, txin.prevout, txindex))
- continue; // previous transaction not in main chain
- if (nTime < txPrev.nTime)
- return false; // Transaction timestamp violation
+ // Input 0 must match the stake hash target per coin age (nBits)
+ const CTxIn& txin = vin[0];
- // Read block header
- CBlock block;
- if (!block.ReadFromDisk(txindex.pos.nFile, txindex.pos.nBlockPos, false))
- return false; // unable to read block of previous transaction
- if (block.GetBlockTime() + AUTO_CHECKPOINT_TRUST_SPAN > nTime)
- continue; // only count coins from at least one week ago
-
- int64 nValueIn = txPrev.vout[txin.prevout.n].nValue;
- CBigNum bnCoinDay = CBigNum(nValueIn) * (nTime-txPrev.nTime) / COIN / (24 * 60 * 60);
- // Calculate hash
- CDataStream ss(SER_GETHASH, VERSION);
- ss << nBits << block.nTime << txPrev.nTime << nTime;
- if (CBigNum(Hash(ss.begin(), ss.end())) <= bnCoinDay * bnTargetPerCoinDay)
- return true;
- }
+ // First try finding the previous transaction in database
+ CTransaction txPrev;
+ CTxIndex txindex;
+ if (!txPrev.ReadFromDisk(txdb, txin.prevout, txindex))
+ return false; // previous transaction not in main chain
+ if (nTime < txPrev.nTime)
+ return false; // Transaction timestamp violation
- return false;
+ // Read block header
+ CBlock block;
+ if (!block.ReadFromDisk(txindex.pos.nFile, txindex.pos.nBlockPos, false))
+ return false; // unable to read block of previous transaction
+ if (block.GetBlockTime() + AUTO_CHECKPOINT_TRUST_SPAN > nTime)
+ return false; // only count coins from at least one week ago
+
+ int64 nValueIn = txPrev.vout[txin.prevout.n].nValue;
+ CBigNum bnCoinDay = CBigNum(nValueIn) * (nTime-txPrev.nTime) / COIN / (24 * 60 * 60);
+ // Calculate hash
+ CDataStream ss(SER_GETHASH, VERSION);
+ ss << nBits << block.nTime << (txindex.pos.nTxPos - txindex.pos.nBlockPos) << txPrev.nTime << txin.prevout.n << nTime;
+ if (CBigNum(Hash(ss.begin(), ss.end())) <= bnCoinDay * bnTargetPerCoinDay)
+ return true;
+ else
+ return false;
}
// ppcoin: total coin age spent in transaction, in the unit of coin-days.
if (vtx[i].IsCoinStake())
return DoS(100, error("CheckBlock() : coinstake in wrong position"));
+ // ppcoin: coinbase output should be empty if proof-of-stake block
+ if (IsProofOfStake() && !vtx[0].vout[0].IsEmpty())
+ return error("CheckBlock() : coinbase output not empty for proof-of-stake block");
+
// Check coinbase timestamp
if (GetBlockTime() > (int64)vtx[0].nTime + nMaxClockDrift)
return DoS(50, error("CheckBlock() : coinbase timestamp is too early"));
nLastCoinStakeCheckTime++;
txCoinStake.nTime = nLastCoinStakeCheckTime;
}
- if (pwallet->CreateCoinStake(txNew.vout[0].scriptPubKey, pblock->nBits, txCoinStake))
+ if (pwallet->CreateCoinStake(pblock->nBits, txCoinStake))
{
pblock->vtx.push_back(txCoinStake);
+ pblock->vtx[0].vout[0].SetEmpty();
break;
}
}
git://git.novaco.in / novacoin.git / blobdiff