[Refactoring] Move ContextualCheckZerocoinStake() to kernel.cpp

Warrows · Warrows · commit 2621b7f3f7da · 2019-06-17T23:49:53.000+02:00
And call it in CheckProofOfStake() which is called by AcceptBlock()
instead of calling it directly from AcceptBlock().
diff --git a/src/kernel.cpp b/src/kernel.cpp
@@ -350,8 +350,33 @@ bool Stake(CStakeInput* stakeInput, unsigned int nBits, unsigned int nTimeBlockF
     return fSuccess;
 }
 
+bool ContextualCheckZerocoinStake(int nPreviousBlockHeight, CStakeInput* stake)
+{
+    if (nPreviousBlockHeight < Params().Zerocoin_Block_V2_Start())
+        return error("%s: zPIV stake block is less than allowed start height", __func__);
+
+    if (CZPivStake* zPIV = dynamic_cast<CZPivStake*>(stake)) {
+        CBlockIndex* pindexFrom = zPIV->GetIndexFrom();
+        if (!pindexFrom)
+            return error("%s: failed to get index associated with zPIV stake checksum", __func__);
+
+        if (chainActive.Height() - pindexFrom->nHeight < Params().Zerocoin_RequiredStakeDepth())
+            return error("%s: zPIV stake does not have required confirmation depth. Current height %d,  stakeInput height %d.", __func__, chainActive.Height(), pindexFrom->nHeight);
+
+        //The checksum needs to be the exact checksum from 200 blocks ago
+        uint256 nCheckpoint200 = chainActive[nPreviousBlockHeight - Params().Zerocoin_RequiredStakeDepth()]->nAccumulatorCheckpoint;
+        uint32_t nChecksum200 = ParseChecksum(nCheckpoint200, libzerocoin::AmountToZerocoinDenomination(zPIV->GetValue()));
+        if (nChecksum200 != zPIV->GetChecksum())
+            return error("%s: accumulator checksum is different than the block 200 blocks previous. stake=%d block200=%d", __func__, zPIV->GetChecksum(), nChecksum200);
+    } else {
+        return error("%s: dynamic_cast of stake ptr failed", __func__);
+    }
+
+    return true;
+}
+
 // Check kernel hash target and coinstake signature
-bool CheckProofOfStake(const CBlock block, uint256& hashProofOfStake, std::unique_ptr<CStakeInput>& stake)
+bool CheckProofOfStake(const CBlock block, uint256& hashProofOfStake, std::unique_ptr<CStakeInput>& stake, int nPreviousBlockHeight)
 {
     const CTransaction tx = block.vtx[1];
     if (!tx.IsCoinStake())
@@ -367,6 +392,9 @@ bool CheckProofOfStake(const CBlock block, uint256& hashProofOfStake, std::uniqu
             return error("%s: spend is using the wrong SpendType (%d)", __func__, (int)spend.getSpendType());
 
         stake = std::unique_ptr<CStakeInput>(new CZPivStake(spend));
+
+        if (!ContextualCheckZerocoinStake(nPreviousBlockHeight, stake.get()))
+            return error("%s: staked zPIV fails context checks", __func__);
     } else {
         // First try finding the previous transaction in database
         uint256 hashBlock;
diff --git a/src/kernel.h b/src/kernel.h
@@ -43,4 +43,6 @@ bool CheckStakeModifierCheckpoints(int nHeight, unsigned int nStakeModifierCheck
 // Get time weight using supplied timestamps
 int64_t GetWeight(int64_t nIntervalBeginning, int64_t nIntervalEnd);
 
+bool ContextualCheckZerocoinStake(int nPreviousBlockHeight, CStakeInput* stake);
+
 #endif // BITCOIN_KERNEL_H
diff --git a/src/main.cpp b/src/main.cpp
@@ -4691,31 +4691,6 @@ bool AcceptBlockHeader(const CBlock& block, CValidationState& state, CBlockIndex
     return true;
 }
 
-bool ContextualCheckZerocoinStake(int nHeight, CStakeInput* stake)
-{
-    if (nHeight < Params().Zerocoin_Block_V2_Start())
-        return error("%s: zPIV stake block is less than allowed start height", __func__);
-
-    if (CZPivStake* zPIV = dynamic_cast<CZPivStake*>(stake)) {
-        CBlockIndex* pindexFrom = zPIV->GetIndexFrom();
-        if (!pindexFrom)
-            return error("%s: failed to get index associated with zPIV stake checksum", __func__);
-
-        if (chainActive.Height() - pindexFrom->nHeight < Params().Zerocoin_RequiredStakeDepth())
-            return error("%s: zPIV stake does not have required confirmation depth. Current height %d,  stakeInput height %d.", __func__, chainActive.Height(), pindexFrom->nHeight);
-
-        //The checksum needs to be the exact checksum from 200 blocks ago
-        uint256 nCheckpoint200 = chainActive[nHeight - Params().Zerocoin_RequiredStakeDepth()]->nAccumulatorCheckpoint;
-        uint32_t nChecksum200 = ParseChecksum(nCheckpoint200, libzerocoin::AmountToZerocoinDenomination(zPIV->GetValue()));
-        if (nChecksum200 != zPIV->GetChecksum())
-            return error("%s: accumulator checksum is different than the block 200 blocks previous. stake=%d block200=%d", __func__, zPIV->GetChecksum(), nChecksum200);
-    } else {
-        return error("%s: dynamic_cast of stake ptr failed", __func__);
-    }
-
-    return true;
-}
-
 bool AcceptBlock(CBlock& block, CValidationState& state, CBlockIndex** ppindex, CDiskBlockPos* dbp, bool fAlreadyCheckedBlock)
 {
     AssertLockHeld(cs_main);
@@ -4754,15 +4729,12 @@ bool AcceptBlock(CBlock& block, CValidationState& state, CBlockIndex** ppindex,
         uint256 hashProofOfStake = 0;
         unique_ptr<CStakeInput> stake;
 
-        if (!CheckProofOfStake(block, hashProofOfStake, stake))
+        if (!CheckProofOfStake(block, hashProofOfStake, stake, pindexPrev->nHeight))
             return state.DoS(100, error("%s: proof of stake check failed", __func__));
 
         if (!stake)
             return error("%s: null stake ptr", __func__);
 
-        if (stake->IsZPIV() && !ContextualCheckZerocoinStake(pindexPrev->nHeight, stake.get()))
-            return state.DoS(100, error("%s: staked zPIV fails context checks", __func__));
-
         uint256 hash = block.GetHash();
         if(!mapProofOfStake.count(hash)) // add to mapProofOfStake
             mapProofOfStake.insert(make_pair(hash, hashProofOfStake));
