Add quorumModifierHash to instant send lock vote (#2505)

* Let GetMasternodeRank also return the block hash at the given height

* Add outpointConfirmedBlock to CTxLockVote and verify it

* Match order of parameters with member order

* Rename outpointConfirmedBlock to quorumModifierHash

* Add overload of GetMasternodeRank that does not return the block hash

src/instantx.cpp

@@ -244,11 +244,16 @@ void CInstantSend::Vote(CTxLockCandidate& txLockCandidate, CConnman& connman)
         int nLockInputHeight = nPrevoutHeight + Params().GetConsensus().nInstantSendConfirmationsRequired - 2;
 
         int nRank;
+        uint256 quorumModifierHash;
         int nMinRequiredProtocol = std::max(MIN_INSTANTSEND_PROTO_VERSION, mnpayments.GetMinMasternodePaymentsProto());
-        if (!mnodeman.GetMasternodeRank(activeMasternodeInfo.outpoint, nRank, nLockInputHeight, nMinRequiredProtocol)) {
+        if (!mnodeman.GetMasternodeRank(activeMasternodeInfo.outpoint, nRank, quorumModifierHash, nLockInputHeight, nMinRequiredProtocol)) {
             LogPrint("instantsend", "CInstantSend::Vote -- Can't calculate rank for masternode %s\n", activeMasternodeInfo.outpoint.ToStringShort());
             continue;
         }
+        if (!deterministicMNManager->IsDeterministicMNsSporkActive()) {
+            // not used until spork15 activation
+            quorumModifierHash = uint256();
+        }
 
         int nSignaturesTotal = COutPointLock::SIGNATURES_TOTAL;
         if (nRank > nSignaturesTotal) {
@@ -282,7 +287,7 @@ void CInstantSend::Vote(CTxLockCandidate& txLockCandidate, CConnman& connman)
 
         // we haven't voted for this outpoint yet, let's try to do this now
         // Please note that activeMasternodeInfo.proTxHash is only valid after spork15 activation
-        CTxLockVote vote(txHash, outpointLockPair.first, activeMasternodeInfo.outpoint, activeMasternodeInfo.proTxHash);
+        CTxLockVote vote(txHash, outpointLockPair.first, activeMasternodeInfo.outpoint, quorumModifierHash, activeMasternodeInfo.proTxHash);
 
         if (!vote.Sign()) {
             LogPrintf("CInstantSend::Vote -- Failed to sign consensus vote\n");
@@ -1052,12 +1057,23 @@ bool CTxLockVote::IsValid(CNode* pnode, CConnman& connman) const
     int nLockInputHeight = coin.nHeight + Params().GetConsensus().nInstantSendConfirmationsRequired - 2;
 
     int nRank;
+    uint256 expectedQuorumModifierHash;
     int nMinRequiredProtocol = std::max(MIN_INSTANTSEND_PROTO_VERSION, mnpayments.GetMinMasternodePaymentsProto());
-    if (!mnodeman.GetMasternodeRank(outpointMasternode, nRank, nLockInputHeight, nMinRequiredProtocol)) {
+    if (!mnodeman.GetMasternodeRank(outpointMasternode, nRank, expectedQuorumModifierHash, nLockInputHeight, nMinRequiredProtocol)) {
         //can be caused by past versions trying to vote with an invalid protocol
         LogPrint("instantsend", "CTxLockVote::IsValid -- Can't calculate rank for masternode %s\n", outpointMasternode.ToStringShort());
         return false;
     }
+    if (!quorumModifierHash.IsNull()) {
+        if (quorumModifierHash != expectedQuorumModifierHash) {
+            LogPrint("instantsend", "CTxLockVote::IsValid -- invalid quorumModifierHash %s, expected %s\n", quorumModifierHash.ToString(), expectedQuorumModifierHash.ToString());
+            return false;
+        }
+    } else if (deterministicMNManager->IsDeterministicMNsSporkActive()) {
+        LogPrint("instantsend", "CTxLockVote::IsValid -- missing quorumModifierHash while DIP3 is active\n");
+        return false;
+    }
+
     LogPrint("instantsend", "CTxLockVote::IsValid -- Masternode %s, rank=%d\n", outpointMasternode.ToStringShort(), nRank);
 
     int nSignaturesTotal = COutPointLock::SIGNATURES_TOTAL;

src/instantx.h

@@ -235,6 +235,7 @@ private:
     COutPoint outpoint;
     // TODO remove this member when the legacy masternode code is removed after DIP3 deployment
     COutPoint outpointMasternode;
+    uint256 quorumModifierHash;
     uint256 masternodeProTxHash;
     std::vector<unsigned char> vchMasternodeSignature;
     // local memory only
@@ -246,16 +247,18 @@ public:
         txHash(),
         outpoint(),
         outpointMasternode(),
+        quorumModifierHash(),
         masternodeProTxHash(),
         vchMasternodeSignature(),
         nConfirmedHeight(-1),
         nTimeCreated(GetTime())
         {}
 
-    CTxLockVote(const uint256& txHashIn, const COutPoint& outpointIn, const COutPoint& outpointMasternodeIn, const uint256& masternodeProTxHashIn) :
+    CTxLockVote(const uint256& txHashIn, const COutPoint& outpointIn, const COutPoint& outpointMasternodeIn, const uint256& quorumModifierHashIn, const uint256& masternodeProTxHashIn) :
         txHash(txHashIn),
         outpoint(outpointIn),
         outpointMasternode(outpointMasternodeIn),
+        quorumModifierHash(quorumModifierHashIn),
         masternodeProTxHash(masternodeProTxHashIn),
         vchMasternodeSignature(),
         nConfirmedHeight(-1),
@@ -270,8 +273,9 @@ public:
         READWRITE(outpoint);
         READWRITE(outpointMasternode);
         if (deterministicMNManager->IsDeterministicMNsSporkActive()) {
-            // Starting with spork15 activation, the proTxHash is included. When we bump to >= 70213, we can remove
+            // Starting with spork15 activation, the proTxHash and quorumModifierHash is included. When we bump to >= 70213, we can remove
             // the surrounding if. We might also remove outpointMasternode as well later
+            READWRITE(quorumModifierHash);
             READWRITE(masternodeProTxHash);
         }
         if (!(s.GetType() & SER_GETHASH)) {

src/masternodeman.cpp

@@ -821,6 +821,12 @@ bool CMasternodeMan::GetMasternodeScores(const uint256& nBlockHash, CMasternodeM
 }
 
 bool CMasternodeMan::GetMasternodeRank(const COutPoint& outpoint, int& nRankRet, int nBlockHeight, int nMinProtocol)
+{
+    uint256 tmp;
+    return GetMasternodeRank(outpoint, nRankRet, tmp, nBlockHeight, nMinProtocol);
+}
+
+bool CMasternodeMan::GetMasternodeRank(const COutPoint& outpoint, int& nRankRet, uint256& blockHashRet, int nBlockHeight, int nMinProtocol)
 {
     nRankRet = -1;
 
@@ -828,8 +834,8 @@ bool CMasternodeMan::GetMasternodeRank(const COutPoint& outpoint, int& nRankRet,
         return false;
 
     // make sure we know about this block
-    uint256 nBlockHash = uint256();
+    blockHashRet = uint256();
-    if (!GetBlockHash(nBlockHash, nBlockHeight)) {
+    if (!GetBlockHash(blockHashRet, nBlockHeight)) {
         LogPrintf("CMasternodeMan::%s -- ERROR: GetBlockHash() failed at nBlockHeight %d\n", __func__, nBlockHeight);
         return false;
     }
@@ -837,7 +843,7 @@ bool CMasternodeMan::GetMasternodeRank(const COutPoint& outpoint, int& nRankRet,
     LOCK(cs);
 
     score_pair_vec_t vecMasternodeScores;
-    if (!GetMasternodeScores(nBlockHash, vecMasternodeScores, nMinProtocol))
+    if (!GetMasternodeScores(blockHashRet, vecMasternodeScores, nMinProtocol))
         return false;
 
     int nRank = 0;

src/masternodeman.h

@@ -187,6 +187,7 @@ public:
 
     bool GetMasternodeRanks(rank_pair_vec_t& vecMasternodeRanksRet, int nBlockHeight = -1, int nMinProtocol = 0);
     bool GetMasternodeRank(const COutPoint &outpoint, int& nRankRet, int nBlockHeight = -1, int nMinProtocol = 0);
+    bool GetMasternodeRank(const COutPoint &outpoint, int& nRankRet, uint256& blockHashRet, int nBlockHeight = -1, int nMinProtocol = 0);
 
     void ProcessMasternodeConnections(CConnman& connman);
     std::pair<CService, std::set<uint256> > PopScheduledMnbRequestConnection();