Introduce block time protocol V2 (15 second windows)

- Port and adapt PIVX commits on time protocol V2 (PR dashpay#1002)
- Port PIVX commits on nTime offset warnings (PR dashpay#1138)
- Adjust chain parameters
- Add several copyright notices

Author: ckti

src/chain.cpp

@@ -124,6 +124,38 @@ unsigned int CBlockIndex::GetStakeEntropyBit() const
     return ((UintToArith256(GetBlockHash()).GetLow64()) & 1);
 }
 
+int CBlockIndex::FutureBlockTimeDrift(const int nHeight, const Consensus::Params& params) const
+{
+    if (params.IsTimeProtocolV2(nHeight))
+        // PoS (TimeV2): 14 seconds
+        return params.nTimeSlotLength - 1;
+
+    // PoS (TimeV1): 3 minutes
+    // PoW: 2 hours
+    return (nHeight >= params.nPosStartHeight) ? MAX_FUTURE_BLOCK_TIME_POS : MAX_FUTURE_BLOCK_TIME_POW;
+}
+
+int64_t CBlockIndex::MaxFutureBlockTime(int64_t nAdjustedTime, const Consensus::Params& params) const
+{
+    return nAdjustedTime + FutureBlockTimeDrift(nHeight+1, params);
+}
+
+int64_t CBlockIndex::MinPastBlockTime(const Consensus::Params& params) const
+{
+    // Time Protocol v1: pindexPrev->MedianTimePast + 1
+    if (!params.IsTimeProtocolV2(nHeight+1))
+        return GetMedianTimePast();
+
+    // on the transition from Time Protocol v1 to v2
+    // pindexPrev->nTime might be in the future (up to the allowed drift)
+    // so we allow the nBlockTimeProtocolV2 to be at most (180-14) seconds earlier than previous block
+    if (nHeight + 1 == params.nBlockTimeProtocolV2)
+        return GetBlockTime() - FutureBlockTimeDrift(nHeight, params) + FutureBlockTimeDrift(nHeight + 1, params);
+
+    // Time Protocol v2: pindexPrev->nTime
+    return GetBlockTime();
+}
+
 arith_uint256 GetBlockProof(const CBlockIndex& block)
 {
     arith_uint256 bnTarget;

src/chain.h

@@ -1,5 +1,9 @@
 // Copyright (c) 2009-2010 Satoshi Nakamoto
 // Copyright (c) 2009-2015 The Bitcoin Core developers
+// Copyright (c) 2011-2013 The PPCoin developers
+// Copyright (c) 2013-2014 The NovaCoin Developers
+// Copyright (c) 2014-2018 The BlackCoin Developers
+// Copyright (c) 2015-2019 The PIVX developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
@@ -18,15 +22,16 @@
  * Maximum amount of time that a block timestamp is allowed to exceed the
  * current network-adjusted time before the block will be accepted.
  */
-static const int64_t MAX_FUTURE_BLOCK_TIME = 2 * 60 * 60;
+static const int64_t MAX_FUTURE_BLOCK_TIME_POW = 2 * 60 * 60;
+static const int64_t MAX_FUTURE_BLOCK_TIME_POS = 3 * 60;
 
 /**
  * Timestamp window used as a grace period by code that compares external
  * timestamps (such as timestamps passed to RPCs, or wallet key creation times)
  * to block timestamps. This should be set at least as high as
- * MAX_FUTURE_BLOCK_TIME.
+ * MAX_FUTURE_BLOCK_TIME_POW.
  */
-static const int64_t TIMESTAMP_WINDOW = MAX_FUTURE_BLOCK_TIME;
+static const int64_t TIMESTAMP_WINDOW = MAX_FUTURE_BLOCK_TIME_POW;
 
 class CBlockFileInfo
 {
@@ -362,6 +367,12 @@ class CBlockIndex
         return pbegin[(pend - pbegin)/2];
     }
 
+    int FutureBlockTimeDrift(const int nHeight, const Consensus::Params& params) const;
+
+    int64_t MaxFutureBlockTime(int64_t nAdjustedTime, const Consensus::Params& params) const;
+
+    int64_t MinPastBlockTime(const Consensus::Params& params) const;
+
     bool IsProofOfWork() const
     {
         return !(nFlags & BLOCK_PROOF_OF_STAKE);

src/chainparams.cpp

@@ -360,6 +360,7 @@ class CMainParams : public CChainParams {
         consensus.nGovernanceMinQuorum = 10;
         consensus.nGovernanceFilterElements = 20000;
         consensus.nMasternodeMinimumConfirmations = 15;
+        consensus.V16DeploymentHeight = std::numeric_limits<int64_t>::max();
         consensus.BIP34Height = 1;
         consensus.BIP34Hash = uint256S("000001364c4ed20f1b240810b5aa91fee23ae9b64b6e746b594b611cf6d8c87b");
         consensus.BIP65Height = consensus.V16DeploymentHeight;
@@ -378,12 +379,17 @@ class CMainParams : public CChainParams {
         // Wagerr specific parameters
         // Proof of Stake parameters
         consensus.nPosStartHeight = 201;
-        consensus.nPivxProtocolV2StartHeight = std::numeric_limits<int>::max();
+        consensus.nBlockTimeProtocolV2 = consensus.V16DeploymentHeight;
         consensus.posLimit = uint256S("000000ffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"); // ~uint256(0) >> 24
+        consensus.posLimit_V2 = uint256S("00000fffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"); // ~uint256(0) >> 20
+        consensus.nTimeSlotLength = 15;
         consensus.nPosTargetSpacing = 1 * 60; // 1 minute
+        consensus.nPosTargetTimespan = 40 * 60; // 40 minutes
+        consensus.nPosTargetTimespan_V2 = 2 * consensus.nTimeSlotLength * 60; // 30 minutes
         consensus.nStakeMinDepth = 600;
+        consensus.nStakeMinAge = 60 * 60; // 1 hour
         consensus.nBlockStakeModifierV1A = 1000;
-        consensus.nBlockStakeModifierV2 = std::numeric_limits<int>::max();
+        consensus.nBlockStakeModifierV2 = consensus.V16DeploymentHeight;
         // ATP parameters
         consensus.ATPStartHeight = std::numeric_limits<int64_t>::max();
         consensus.WgrAddrPrefix = "wgr";
@@ -547,7 +553,7 @@ class CTestNetParams : public CChainParams {
         consensus.nGovernanceMinQuorum = 1;
         consensus.nGovernanceFilterElements = 500;
         consensus.nMasternodeMinimumConfirmations = 1;
-        consensus.V16DeploymentHeight = 1600000;
+        consensus.V16DeploymentHeight = std::numeric_limits<int>::max();
         consensus.BIP34Height = 1;
         consensus.BIP34Hash = uint256S("0000065432f43b3efb23bd0f63fe33d00d02a5f36233fe1b982c08274d58ef12");
         consensus.BIP65Height = consensus.V16DeploymentHeight;
@@ -566,10 +572,15 @@ class CTestNetParams : public CChainParams {
         // Wagerr specific parameters
         // Proof of Stake parameters
         consensus.nPosStartHeight = 201;
-        consensus.nPivxProtocolV2StartHeight = std::numeric_limits<int>::max();
+        consensus.nBlockTimeProtocolV2 = consensus.V16DeploymentHeight;
         consensus.posLimit = uint256S("000000ffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"); // ~uint256(0) >> 24
+        consensus.posLimit_V2 = uint256S("00000fffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"); // ~uint256(0) >> 20
+        consensus.nTimeSlotLength = 15;
         consensus.nPosTargetSpacing = 1 * 60; // 1 minute
+        consensus.nPosTargetTimespan = 40 * 60; // 40 minutes
+        consensus.nPosTargetTimespan_V2 = 2 * consensus.nTimeSlotLength * 60; // 30 minutes
         consensus.nStakeMinDepth = 100;
+        consensus.nStakeMinAge = 60 * 60; // 1 hour
         consensus.nBlockStakeModifierV1A = 51197;
         consensus.nBlockStakeModifierV2 = std::numeric_limits<int>::max();
         // ATP parameters
@@ -737,12 +748,17 @@ class CDevNetParams : public CChainParams {
         // Wagerr specific parameters
         // Proof of Stake parameters
         consensus.nPosStartHeight = 201;
-        consensus.nPivxProtocolV2StartHeight = 2000;
+        consensus.nBlockTimeProtocolV2 = consensus.V16DeploymentHeight;
         consensus.posLimit = uint256S("7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"); // ~uint256(0) >> 1
+        consensus.posLimit_V2 = uint256S("7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"); // ~uint256(0) >> 1
+        consensus.nTimeSlotLength = 15;
         consensus.nPosTargetSpacing = 1 * 60; // 1 minute
+        consensus.nPosTargetTimespan = 40 * 60; // 40 minutes
+        consensus.nPosTargetTimespan_V2 = 2 * consensus.nTimeSlotLength * 60; // 30 minutes
         consensus.nStakeMinDepth = 100;
+        consensus.nStakeMinAge = 60 * 60; // 1 hour
         consensus.nBlockStakeModifierV1A = 1000;
-        consensus.nBlockStakeModifierV2 = consensus.nPivxProtocolV2StartHeight;
+        consensus.nBlockStakeModifierV2 = consensus.V16DeploymentHeight;
         // ATP parameters
         consensus.ATPStartHeight = std::numeric_limits<int64_t>::max();
         consensus.WgrAddrPrefix = "wgrtest";
@@ -887,6 +903,7 @@ class CRegTestParams : public CChainParams {
         consensus.nGovernanceMinQuorum = 1;
         consensus.nGovernanceFilterElements = 100;
         consensus.nMasternodeMinimumConfirmations = 1;
+        consensus.V16DeploymentHeight = 300;
         consensus.BIP34Height = 100000000; // BIP34 has not activated on regtest (far in the future so block v1 are not rejected in tests)
         consensus.BIP34Hash = uint256();
         consensus.BIP65Height = 1351; // BIP65 activated on regtest (Used in rpc activation tests)
@@ -905,12 +922,16 @@ class CRegTestParams : public CChainParams {
         // Wagerr specific parameters
         // Proof of Stake parameters
         consensus.nPosStartHeight = 201;
-        consensus.nPivxProtocolV2StartHeight = 2000;
+        consensus.nBlockTimeProtocolV2 = consensus.V16DeploymentHeight;
         consensus.posLimit = uint256S("7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"); // ~uint256(0) >> 1
+        consensus.posLimit_V2 = uint256S("7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"); // ~uint256(0) >> 1
+        consensus.nTimeSlotLength = 15;
         consensus.nPosTargetSpacing = 1 * 60; // 1 minute
+        consensus.nPosTargetTimespan = 40 * 60; // 40 minutes
+        consensus.nPosTargetTimespan_V2 = 2 * consensus.nTimeSlotLength * 60; // 30 minutes
         consensus.nStakeMinDepth = 100;
         consensus.nBlockStakeModifierV1A = 1000;
-        consensus.nBlockStakeModifierV2 = consensus.nPivxProtocolV2StartHeight;
+        consensus.nBlockStakeModifierV2 = consensus.V16DeploymentHeight;
         // ATP parameters
         consensus.ATPStartHeight = std::numeric_limits<int64_t>::max();
         consensus.WgrAddrPrefix = "wgrreg";

src/consensus/params.h

@@ -190,13 +190,21 @@ struct Params {
 
     /** Proof of stake parameters */
     int64_t nPosStartHeight;
-    int64_t nPivxProtocolV2StartHeight;
     uint256 posLimit;
+    uint256 posLimit_V2;
     int64_t nPosTargetSpacing;
+    int64_t nPosTargetTimespan;
+    int64_t nPosTargetTimespan_V2;
     int32_t nStakeMinDepth;
+    int32_t nStakeMinAge;
     int64_t nBlockStakeModifierV1A;
     int64_t nBlockStakeModifierV2;
 
+    /** Time Protocol V2 **/
+    int nBlockTimeProtocolV2;
+    bool IsTimeProtocolV2(const int nHeight) const { return nHeight >= nBlockTimeProtocolV2; }
+    int nTimeSlotLength;
+
     /** ATP parameters */
     int64_t ATPStartHeight;
     std::string WgrAddrPrefix;

src/miner.cpp

@@ -1,5 +1,9 @@
 // Copyright (c) 2009-2010 Satoshi Nakamoto
 // Copyright (c) 2009-2015 The Bitcoin Core developers
+// Copyright (c) 2011-2013 The PPCoin developers
+// Copyright (c) 2013-2014 The NovaCoin Developers
+// Copyright (c) 2014-2018 The BlackCoin Developers
+// Copyright (c) 2015-2019 The PIVX developers
 // Copyright (c) 2014-2021 The Dash Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
@@ -61,7 +65,12 @@ uint64_t nLastBlockSize = 0;
 int64_t UpdateTime(CBlockHeader* pblock, const Consensus::Params& consensusParams, const CBlockIndex* pindexPrev)
 {
     int64_t nOldTime = pblock->nTime;
-    int64_t nNewTime = std::max(pindexPrev->GetMedianTimePast()+1, GetAdjustedTime());
+    int64_t nNewTime;
+    if (consensusParams.IsTimeProtocolV2(pindexPrev->nHeight + 1)) {
+        nNewTime = GetTimeSlot(GetAdjustedTime());
+    } else {
+        nNewTime = std::max(pindexPrev->GetMedianTimePast()+1, GetAdjustedTime());
+    }
 
     if (nOldTime < nNewTime)
         pblock->nTime = nNewTime;
@@ -139,7 +148,7 @@ bool BlockAssembler::SplitCoinstakeVouts(std::shared_ptr<CMutableTransaction> co
 }
 
 std::unique_ptr<CBlockTemplate> BlockAssembler::CreateNewBlock(const CScript& scriptPubKeyIn,
-                                    std::shared_ptr<CMutableTransaction> pCoinstakeTx, std::shared_ptr<CStakeInput> coinstakeInput, unsigned int nTxNewTime)
+                                    std::shared_ptr<CMutableTransaction> pCoinstakeTx, std::shared_ptr<CStakeInput> coinstakeInput, uint64_t nTxNewTime)
 {
     CBasicKeyStore tempKeystore;
 #ifdef ENABLE_WALLET

src/miner.h

@@ -162,7 +162,7 @@ class BlockAssembler
 
     /** Construct a new block template with coinbase to scriptPubKeyIn */
     std::unique_ptr<CBlockTemplate> CreateNewBlock(const CScript& scriptPubKeyIn,
-            std::shared_ptr<CMutableTransaction> pCoinstakeTx = nullptr, std::shared_ptr<CStakeInput> coinstakeInput = nullptr, unsigned int nTxNewTime = 0);
+            std::shared_ptr<CMutableTransaction> pCoinstakeTx = nullptr, std::shared_ptr<CStakeInput> coinstakeInput = nullptr, uint64_t nTxNewTime = 0);
 
 private:
     // utility functions

src/net.cpp

@@ -2338,6 +2338,32 @@ int CConnman::GetExtraOutboundCount()
     return std::max(nOutbound - nMaxOutbound, 0);
 }
 
+void CConnman::CheckOffsetDisconnectedPeers(const CNetAddr& ip)
+{
+    int nConnections = 0;
+    {
+        LOCK(cs_vNodes);
+        for (CNode* pnode : vNodes) {
+            if (pnode->fSuccessfullyConnected)
+                nConnections++;
+            if (nConnections == 2)
+                return;
+        }
+    }
+
+    // Not enough connections. Insert peer.
+    static std::set<CNetAddr> setOffsetDisconnectedPeers;
+    setOffsetDisconnectedPeers.insert(ip);
+    if (setOffsetDisconnectedPeers.size() >= 16) {
+        // clear the set
+        setOffsetDisconnectedPeers.clear();
+        // Trigger the warning
+        std::string strMessage = _("Warning: Peers are being disconnected due time differences. Please check that your computer's date and time are correct! If your clock is wrong Wagerr Core will not work properly.");
+        LogPrintf("*** %s\n", strMessage);
+        uiInterface.ThreadSafeMessageBox(strMessage, "", CClientUIInterface::MSG_ERROR);
+    }
+}
+
 void CConnman::ThreadOpenConnections(const std::vector<std::string> connect)
 {
     // Connect to specific addresses

src/net.h

@@ -414,6 +414,8 @@ friend class CNode;
     // not yet fully disconnected.
     int GetExtraOutboundCount();
 
+    void CheckOffsetDisconnectedPeers(const CNetAddr& ip);
+
     bool AddNode(const std::string& node);
     bool RemoveAddedNode(const std::string& node);
     std::vector<AddedNodeInfo> GetAddedNodeInfo();

src/net_processing.cpp

@@ -2319,6 +2319,13 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
 
         int64_t nTimeOffset = nTime - GetTime();
         pfrom->nTimeOffset = nTimeOffset;
+        const int nTimeSlotLength = Params().GetConsensus().nTimeSlotLength;
+        if (abs64(nTimeOffset) > 2 * nTimeSlotLength) {
+            LogPrintf("timeOffset (%d seconds) too large. Disconnecting node %s\n",
+                    nTimeOffset, pfrom->addr.ToString().c_str());
+            pfrom->fDisconnect = true;
+            connman->CheckOffsetDisconnectedPeers(pfrom->addr);
+        }
         AddTimeData(pfrom->addr, nTimeOffset);
 
         // Feeler connections exist only to verify if address is online.

src/pos/kernel.cpp

@@ -1,5 +1,7 @@
-// Copyright (c) 2012-2013 The PPCoin developers
-// Copyright (c) 2015-2018 The PIVX developers
+// Copyright (c) 2011-2013 The PPCoin developers
+// Copyright (c) 2013-2014 The NovaCoin Developers
+// Copyright (c) 2014-2018 The BlackCoin Developers
+// Copyright (c) 2015-2019 The PIVX developers
 // Copyright (c) 2018-2019 The Ion developers
 // Distributed under the MIT/X11 software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
@@ -229,7 +231,7 @@ bool ComputeNextStakeModifier(const CBlockIndex* pindexPrev, uint64_t& nStakeMod
 
 // The stake modifier used to hash for a stake kernel is chosen as the stake
 // modifier about a selection interval later than the coin generating the kernel
-bool GetKernelStakeModifier(uint256 hashBlockFrom, uint64_t& nStakeModifier, int& nStakeModifierHeight, int64_t& nStakeModifierTime, bool fPrintProofOfStake)
+bool GetKernelStakeModifier(const uint256& hashBlockFrom, uint64_t& nStakeModifier, int& nStakeModifierHeight, int64_t& nStakeModifierTime, bool fPrintProofOfStake)
 {
     nStakeModifier = 0;
     if (!mapBlockIndex.count(hashBlockFrom))
@@ -316,7 +318,7 @@ bool HasStakeMinAgeOrDepth(const int contextHeight, const uint32_t contextTime,
 {
     // before stake modifier V2, the age required was 60 * 60 (1 hour) / not required on regtest
     if (contextHeight < Params().GetConsensus().nBlockStakeModifierV2)
-        return (Params().NetworkIDString() == CBaseChainParams::REGTEST || (utxoFromBlockTime + 3600 <= contextTime));
+        return (Params().NetworkIDString() == CBaseChainParams::REGTEST || (utxoFromBlockTime + Params().GetConsensus().nStakeMinAge <= contextTime));
 
     // after stake modifier V2, we require the utxo to be nStakeMinDepth deep in the chain
     return (contextHeight - utxoFromBlockHeight >= Params().GetConsensus().nStakeMinDepth);
@@ -349,7 +351,7 @@ bool ContextualCheckZerocoinStake(int nPreviousBlockHeight, CStakeInput* stake)
 }
 
 // Check kernel hash target and coinstake signature
-bool initStakeInput(const CBlock block, std::unique_ptr<CStake>& ionStake, std::unique_ptr<CZStake>& zStake, int nPreviousBlockHeight) {
+bool initStakeInput(const CBlock& block, std::unique_ptr<CStake>& ionStake, std::unique_ptr<CZStake>& zStake, int nPreviousBlockHeight) {
     const CTransaction tx = *block.vtx[1];
     if (!tx.IsCoinStake())
         return error("%s : called on non-coinstake %s", __func__, tx.GetHash().GetHex());
@@ -390,7 +392,7 @@ bool initStakeInput(const CBlock block, std::unique_ptr<CStake>& ionStake, std::
 }
 
 // Check kernel hash target and coinstake signature
-bool CheckProofOfStake(const CBlock block, uint256& hashProofOfStake, const CBlockIndex* pindex)
+bool CheckProofOfStake(const CBlock& block, uint256& hashProofOfStake, const CBlockIndex* pindex)
 {
     std::unique_ptr<CStake> ionStake;
     std::unique_ptr<CZStake> zStake;
@@ -432,13 +434,6 @@ bool CheckProofOfStake(const CBlock block, uint256& hashProofOfStake, const CBlo
     return true;
 }
 
-// Check whether the coinstake timestamp meets protocol
-bool CheckCoinStakeTimestamp(int64_t nTimeBlock, int64_t nTimeTx)
-{
-    // v0.3 protocol
-    return (nTimeBlock == nTimeTx);
-}
-
 // Get stake modifier checksum
 unsigned int GetStakeModifierChecksum(const CBlockIndex* pindex)
 {
@@ -465,6 +460,13 @@ bool CheckStakeModifierCheckpoints(int nHeight, unsigned int nStakeModifierCheck
     return true;
 }
 
+// Timestamp for time protocol V2: slot duration 15 seconds
+int64_t GetTimeSlot(const int64_t nTime)
+{
+    const int slotLen = Params().GetConsensus().nTimeSlotLength;
+    return (nTime / slotLen) * slotLen;
+}
+
 bool SetPOSParameters(const CBlock& block, CValidationState& state, CBlockIndex* pindexNew) {
     AssertLockHeld(cs_main);