Transactions verification update

CheckBlock(): allow coinbase timestamp drift, add nonce checking for proof-of-stake.

diff --git a/src/kernel.cpp b/src/kernel.cpp
index a0d1bdb..bd1cdf3 100644 (file)
--- a/src/kernel.cpp
+++ b/src/kernel.cpp
@@ -369,13 +369,6 @@ bool CheckProofOfStake(const CTransaction& tx, unsigned int nBits, uint256& hash
     return true;
 }
 
-// Check whether the coinstake timestamp meets protocol
-bool CheckCoinStakeTimestamp(int64 nTimeBlock, int64 nTimeTx)
-{
-    // v0.3 protocol
-    return (nTimeBlock == nTimeTx);
-}
-
 // Get stake modifier checksum
 unsigned int GetStakeModifierChecksum(const CBlockIndex* pindex)
 {

diff --git a/src/kernel.h b/src/kernel.h
index dc2fbb0..00c7163 100644 (file)
--- a/src/kernel.h
+++ b/src/kernel.h
@@ -24,9 +24,6 @@ bool CheckStakeKernelHash(unsigned int nBits, const CBlock& blockFrom, unsigned
 // Sets hashProofOfStake on success return
 bool CheckProofOfStake(const CTransaction& tx, unsigned int nBits, uint256& hashProofOfStake, uint256& targetProofOfStake);
 
-// Check whether the coinstake timestamp meets protocol
-bool CheckCoinStakeTimestamp(int64 nTimeBlock, int64 nTimeTx);
-
 // Get stake modifier checksum
 unsigned int GetStakeModifierChecksum(const CBlockIndex* pindex);
 

diff --git a/src/main.cpp b/src/main.cpp
index e14b73e..090dd4b 100644 (file)
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -996,7 +996,7 @@ CBigNum inline GetProofOfStakeLimit(int nHeight, unsigned int nTime)
 }
 
 // miner's coin base reward based on nBits
-int64 GetProofOfWorkReward(unsigned int nBits)
+int64 GetProofOfWorkReward(unsigned int nBits, int64 nFees)
 {
     CBigNum bnSubsidyLimit = MAX_MINT_PROOF_OF_WORK;
 
@@ -1031,7 +1031,7 @@ int64 GetProofOfWorkReward(unsigned int nBits)
     if (fDebug && GetBoolArg("-printcreation"))
         printf("GetProofOfWorkReward() : create=%s nBits=0x%08x nSubsidy=%"PRI64d"\n", FormatMoney(nSubsidy).c_str(), nBits, nSubsidy);
 
-    return min(nSubsidy, MAX_MINT_PROOF_OF_WORK);
+    return min(nSubsidy, MAX_MINT_PROOF_OF_WORK) + nFees;
 }
 
 // miner's coin stake reward based on nBits and coin age spent (coin-days)
@@ -1638,6 +1638,8 @@ bool CBlock::ConnectBlock(CTxDB& txdb, CBlockIndex* pindex, bool fJustCheck)
     if (!CheckBlock(!fJustCheck, !fJustCheck, false))
         return false;
 
+    bool fProtocol048 = fTestNet || VALIDATION_SWITCH_TIME < nTime;
+
     // Do not allow blocks that contain transactions which 'overwrite' older transactions,
     // unless those are already completely spent.
     // If such overwrites are allowed, coinbases and transactions depending upon those
@@ -1721,15 +1723,26 @@ bool CBlock::ConnectBlock(CTxDB& txdb, CBlockIndex* pindex, bool fJustCheck)
         mapQueuedChanges[hashTx] = CTxIndex(posThisTx, tx.vout.size());
     }
 
-    // ppcoin: track money supply and mint amount info
+    if (IsProofOfWork())
+    {
+        int64 nBlockReward = GetProofOfWorkReward(nBits, fProtocol048 ? nFees : 0);
+
+        // Check coinbase reward
+        if (vtx[0].GetValueOut() > nBlockReward)
+            return error("CheckBlock() : coinbase reward exceeded (actual=%"PRI64d" vs calculated=%"PRI64d")",
+                   vtx[0].GetValueOut(),
+                   nBlockReward);
+    }
+
+    // track money supply and mint amount info
     pindex->nMint = nValueOut - nValueIn + nFees;
     pindex->nMoneySupply = (pindex->pprev? pindex->pprev->nMoneySupply : 0) + nValueOut - nValueIn;
     if (!txdb.WriteBlockIndex(CDiskBlockIndex(pindex)))
         return error("Connect() : WriteBlockIndex for pindex failed");
 
-    // ppcoin: fees are not collected by miners as in bitcoin
-    // ppcoin: fees are destroyed to compensate the entire network
-    if (fDebug && GetBoolArg("-printcreation"))
+    // fees are not collected by proof-of-stake miners
+    // fees are destroyed to compensate the entire network
+    if (fProtocol048 && fDebug && IsProofOfStake() && GetBoolArg("-printcreation"))
         printf("ConnectBlock() : destroy=%s nFees=%"PRI64d"\n", FormatMoney(nFees).c_str(), nFees);
 
     if (fJustCheck)
@@ -2155,6 +2168,8 @@ bool CBlock::CheckBlock(bool fCheckPOW, bool fCheckMerkleRoot, bool fCheckSig) c
     if (vtx.empty() || vtx.size() > MAX_BLOCK_SIZE || ::GetSerializeSize(*this, SER_NETWORK, PROTOCOL_VERSION) > MAX_BLOCK_SIZE)
         return DoS(100, error("CheckBlock() : size limits failed"));
 
+    bool fProtocol048 = fTestNet || VALIDATION_SWITCH_TIME < nTime;
+
     // Check proof of work matches claimed amount
     if (fCheckPOW && IsProofOfWork() && !CheckProofOfWork(GetHash(), nBits))
         return DoS(50, error("CheckBlock() : proof of work failed"));
@@ -2166,16 +2181,38 @@ bool CBlock::CheckBlock(bool fCheckPOW, bool fCheckMerkleRoot, bool fCheckSig) c
     // First transaction must be coinbase, the rest must not be
     if (vtx.empty() || !vtx[0].IsCoinBase())
         return DoS(100, error("CheckBlock() : first tx is not coinbase"));
+
+    if (!fProtocol048)
+    {
+        // Check coinbase timestamp
+        if (GetBlockTime() < (int64)vtx[0].nTime)
+            return DoS(100, error("CheckBlock() : coinbase timestamp violation"));
+    }
+    else
+    {
+        // Check coinbase timestamp
+        if (GetBlockTime() < PastDrift((int64)vtx[0].nTime))
+            return DoS(50, error("CheckBlock() : coinbase timestamp is too late"));
+    }
+
     for (unsigned int i = 1; i < vtx.size(); i++)
+    {
         if (vtx[i].IsCoinBase())
             return DoS(100, error("CheckBlock() : more than one coinbase"));
 
-    // Check coinbase timestamp
-    if (GetBlockTime() > FutureDrift((int64)vtx[0].nTime))
-        return DoS(50, error("CheckBlock() : coinbase timestamp is too early"));
+        // Check transaction timestamp
+        if (GetBlockTime() < (int64)vtx[i].nTime)
+            return DoS(50, error("CheckBlock() : block timestamp earlier than transaction timestamp"));
+    }
 
     if (IsProofOfStake())
     {
+        if (fProtocol048)
+        {
+            if (nNonce != 0)
+                return DoS(100, error("CheckBlock() : non-zero nonce in proof-of-stake block"));
+        }
+
         // Coinbase output should be empty if proof-of-stake block
         if (vtx[0].vout.size() != 1 || !vtx[0].vout[0].IsEmpty())
             return DoS(100, error("CheckBlock() : coinbase output not empty for proof-of-stake block"));
@@ -2188,7 +2225,7 @@ bool CBlock::CheckBlock(bool fCheckPOW, bool fCheckMerkleRoot, bool fCheckSig) c
                 return DoS(100, error("CheckBlock() : more than one coinstake"));
 
         // Check coinstake timestamp
-        if (!CheckCoinStakeTimestamp(GetBlockTime(), (int64)vtx[1].nTime))
+        if (GetBlockTime() != (int64)vtx[1].nTime)
             return DoS(50, error("CheckBlock() : coinstake timestamp violation nTimeBlock=%"PRI64d" nTimeTx=%u", GetBlockTime(), vtx[1].nTime));
 
         // NovaCoin: check proof-of-stake block signature
@@ -2197,13 +2234,6 @@ bool CBlock::CheckBlock(bool fCheckPOW, bool fCheckMerkleRoot, bool fCheckSig) c
     }
     else
     {
-        int64 nReward = GetProofOfWorkReward(nBits);
-        // Check coinbase reward
-        if (vtx[0].GetValueOut() > nReward)
-            return DoS(50, error("CheckBlock() : coinbase reward exceeded (actual=%"PRI64d" vs calculated=%"PRI64d")",
-                   vtx[0].GetValueOut(),
-                   nReward));
-
         // Should we check proof-of-work block signature or not?
         //
         // * Always skip on TestNet
@@ -2225,10 +2255,6 @@ bool CBlock::CheckBlock(bool fCheckPOW, bool fCheckMerkleRoot, bool fCheckSig) c
     {
         if (!tx.CheckTransaction())
             return DoS(tx.nDoS, error("CheckBlock() : CheckTransaction failed"));
-
-        // ppcoin: check transaction timestamp
-        if (GetBlockTime() < (int64)tx.nTime)
-            return DoS(50, error("CheckBlock() : block timestamp earlier than transaction timestamp"));
     }
 
     // Check for duplicate txids. This is caught by ConnectInputs(),

diff --git a/src/main.h b/src/main.h
index 6b30019..84f93f7 100644 (file)
--- a/src/main.h
+++ b/src/main.h
@@ -113,7 +113,7 @@ bool LoadExternalBlockFile(FILE* fileIn);
 
 bool CheckProofOfWork(uint256 hash, unsigned int nBits);
 unsigned int GetNextTargetRequired(const CBlockIndex* pindexLast, bool fProofOfStake);
-int64 GetProofOfWorkReward(unsigned int nBits);
+int64 GetProofOfWorkReward(unsigned int nBits, int64 nFees=0);
 int64 GetProofOfStakeReward(int64 nCoinAge, unsigned int nBits, unsigned int nTime, bool bCoinYearOnly=false);
 unsigned int ComputeMinWork(unsigned int nBase, int64 nTime);
 unsigned int ComputeMinStake(unsigned int nBase, int64 nTime, unsigned int nBlockTime);

diff --git a/src/miner.cpp b/src/miner.cpp
index 0038474..9926765 100644 (file)
--- a/src/miner.cpp
+++ b/src/miner.cpp
@@ -355,7 +355,10 @@ CBlock* CreateNewBlock(CWallet* pwallet, bool fProofOfStake)
             printf("CreateNewBlock(): total size %"PRI64u"\n", nBlockSize);
 
         if (!fProofOfStake)
-            pblock->vtx[0].vout[0].nValue = GetProofOfWorkReward(pblock->nBits);
+        {
+            bool fProtocol048 = fTestNet || VALIDATION_SWITCH_TIME < pblock->nTime;
+            pblock->vtx[0].vout[0].nValue = GetProofOfWorkReward(pblock->nBits, fProtocol048 ? nFees : 0);
+        }
 
         // Fill in header
         pblock->hashPrevBlock  = pindexPrev->GetBlockHash();