Merge branch 'proof_check' into 'mn_pos'

proof hash checking added to connect block

See merge request presstab/crown-core!1

src/main.cpp

@@ -1408,7 +1408,7 @@ bool AcceptableInputs(CTxMemPool& pool, CValidationState &state, const CTransact
 }
 
 /** Return transaction in tx, and if it was found inside a block, its hash is placed in hashBlock */
-bool GetTransaction(const uint256 &hash, CTransaction &txOut, uint256 &hashBlock, bool fAllowSlow)
+bool GetTransaction(const uint256 &hash, CTransaction &txOut, uint256& hashBlock, bool fAllowSlow)
 {
     CBlockIndex *pindexSlow = NULL;
     {
@@ -2073,7 +2073,7 @@ void ThreadScriptCheck() {
     scriptcheckqueue.Thread();
 }
 
-bool CheckBlockProofPointer(const CBlock& block, CPubKey& pubkeyMasternode)
+bool CheckBlockProofPointer(const CBlock& block, CPubKey& pubkeyMasternode, COutPoint& outpoint)
 {
     StakePointer stakePointer = block.stakePointer;
     if (!mapBlockIndex.count(stakePointer.hashBlock))
@@ -2097,8 +2097,10 @@ bool CheckBlockProofPointer(const CBlock& block, CPubKey& pubkeyMasternode)
             if (!ExtractDestination(tx.vout[stakePointer.nPos].scriptPubKey, dest))
                 return error("%s: failed to get destination from scriptPubKey", __func__);
 
-            if (CBitcoinAddress(stakePointer.hashPubKey).ToString() != CBitcoinAddress(dest).ToString())
-                return error("%s: Pubkeyhash from proof does not match stakepointer", __func__);
+//            if (CBitcoinAddress(stakePointer.hashPubKey).ToString() != CBitcoinAddress(dest).ToString())
+//                return error("%s: Pubkeyhash from proof does not match stakepointer", __func__);
+
+            outpoint = COutPoint(stakePointer.txid, stakePointer.nPos);
 
             found = true;
             break;
@@ -2128,7 +2130,8 @@ bool ConnectBlock(const CBlock& block, CValidationState& state, CBlockIndex* pin
                     "pow-end");
 
         CPubKey pubkeyMasternode;
-        if (!CheckBlockProofPointer(block, pubkeyMasternode))
+        COutPoint outpoint;
+        if (!CheckBlockProofPointer(block, pubkeyMasternode, outpoint))
             return state.DoS(100, error("%s: Invalid block proof pointer", __func__), REJECT_INVALID,
                              "signature-invalid");
 
@@ -2136,6 +2139,18 @@ bool ConnectBlock(const CBlock& block, CValidationState& state, CBlockIndex* pin
             return state.DoS(100, error("%s: Invalid signature", __func__), REJECT_INVALID,
                              "signature-invalid");
 
+        CTransaction txPayment;
+        uint256 hashPrevBlock;
+        if (!GetTransaction(outpoint.hash, txPayment, hashPrevBlock, true)) {
+            return state.DoS(100, error("%s: Cannot find MN or SN payment", __func__), REJECT_INVALID, "tx-invalid");
+        }
+
+        CBlockIndex* pindexFrom = mapBlockIndex.at(block.stakePointer.hashBlock);
+
+        if (!CheckProofOfStake(block, pindexFrom, outpoint, txPayment)) {
+            return state.DoS(100, error("%s: Proof of Stake check failed", __func__), REJECT_INVALID, "PoS invalid");
+        }
+
     } else if (block.IsProofOfStake()) {
         return state.DoS(100, error("%s: Proof of Stake block submitted before PoW end", __func__), REJECT_INVALID,
                          "pos-early");

src/mn-pos/stakepointer.h

@@ -2,6 +2,7 @@
 #define CROWNCOIN_PROOFPOINTER_H
 
 #include "uint256.h"
+#include "serialize.h"
 
 /*
  *  Crown's masternode staking consensus layer use a "staking node proof pointer" that will point to the most recent
@@ -29,6 +30,16 @@ struct StakePointer
         hashPubKey = uint160();
         nPos = 0;
     }
+
+    ADD_SERIALIZE_METHODS;
+
+    template <typename Stream, typename Operation>
+    inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion) {
+        READWRITE(hashBlock);
+        READWRITE(txid);
+        READWRITE(nPos);
+        READWRITE(hashPubKey);
+    }
 };
 
 #endif //CROWNCOIN_PROOFPOINTER_H

src/mn-pos/stakevalidation.cpp

 #include "stakevalidation.h"
+#include "kernel.h"
 
 #include <primitives/block.h>
+#include <chain.h>
 #include <pubkey.h>
+#include <util.h>
+#include <arith_uint256.h>
 
 bool CheckBlockSignature(const CBlock& block, const CPubKey& pubkeyMasternode)
 {
@@ -9,3 +13,29 @@ bool CheckBlockSignature(const CBlock& block, const CPubKey& pubkeyMasternode)
     return pubkeyMasternode.Verify(hashBlock, block.vchBlockSig);
 }
 
+// Check kernel hash target and coinstake signature
+bool CheckProofOfStake(const CBlock& block, const CBlockIndex* prevBlock, const COutPoint& outpoint, const CTransaction& txPayment)
+{
+    const CTransaction tx = block.vtx[1];
+    if (!tx.IsCoinStake())
+        return error("CheckProofOfStake() : called on non-coinstake %s", tx.GetHash().ToString().c_str());
+
+    CAmount nMNPayment = txPayment.vout[1].nValue;
+    CAmount nSNPayment = txPayment.vout[2].nValue;
+
+    auto pairOut = std::make_pair(outpoint.hash, outpoint.n);
+
+    Kernel kernel(pairOut, (outpoint.n == 1 ? nMNPayment : nSNPayment), uint256(), prevBlock->GetBlockTime(), block.nTime);
+
+    bool fNegative;
+    bool fOverflow;
+    arith_uint256 bnTarget;
+
+    bnTarget.SetCompact(block.nBits, &fNegative, &fOverflow);
+
+    // Check range
+    if (fNegative || bnTarget == 0 || fOverflow)
+        return error("CheckProofOfStake() : nBits below minimum stake");
+
+    return kernel.IsValidProof(ArithToUint256(bnTarget));
+}
\ No newline at end of file

src/mn-pos/stakevalidation.h

@@ -3,7 +3,13 @@
 
 class CBlock;
 class CPubKey;
+class CBlockIndex;
+class COutPoint;
+class CTransaction;
 
 bool CheckBlockSignature(const CBlock& block, const CPubKey& pubkeyMasternode);
 
+// Check kernel hash target and coinstake signature
+bool CheckProofOfStake(const CBlock& block, const CBlockIndex* prevBlock, const COutPoint& outpoint, const CTransaction& txPayment);
+
 #endif //CROWNCOIN_STAKEVALIDATION_H