[PoS] Stake Modifier V2

src/chain.h

@@ -7,6 +7,7 @@
 #ifndef BITCOIN_CHAIN_H
 #define BITCOIN_CHAIN_H
 
+#include "chainparams.h"
 #include "pow.h"
 #include "primitives/block.h"
 #include "tinyformat.h"
@@ -155,6 +156,7 @@ class CBlockIndex
         BLOCK_STAKE_MODIFIER = (1 << 2), // regenerated stake modifier
     };
 
+
     // proof-of-stake specific fields
     uint256 GetBlockTrust() const;
     uint64_t nStakeModifier;             // hash modifier for proof-of-stake
@@ -164,6 +166,7 @@ class CBlockIndex
     uint256 hashProofOfStake;
     int64_t nMint;
     int64_t nMoneySupply;
+    uint256 nStakeModifierV2;
 
     //! block header
     int nVersion;
@@ -199,6 +202,7 @@ class CBlockIndex
         nMoneySupply = 0;
         nFlags = 0;
         nStakeModifier = 0;
+        nStakeModifierV2 = uint256();
         nStakeModifierChecksum = 0;
         prevoutStake.SetNull();
         nStakeTime = 0;
@@ -233,22 +237,10 @@ class CBlockIndex
         if(block.nVersion > 3)
             nAccumulatorCheckpoint = block.nAccumulatorCheckpoint;
 
-        //Proof of Stake
-        bnChainTrust = uint256();
-        nMint = 0;
-        nMoneySupply = 0;
-        nFlags = 0;
-        nStakeModifier = 0;
-        nStakeModifierChecksum = 0;
-        hashProofOfStake = uint256();
-
         if (block.IsProofOfStake()) {
             SetProofOfStake();
             prevoutStake = block.vtx[1].vin[0].prevout;
             nStakeTime = block.nTime;
-        } else {
-            prevoutStake.SetNull();
-            nStakeTime = 0;
         }
     }
 
@@ -477,7 +469,14 @@ class CDiskBlockIndex : public CBlockIndex
         READWRITE(nMint);
         READWRITE(nMoneySupply);
         READWRITE(nFlags);
-        READWRITE(nStakeModifier);
+
+        // v1/v2 modifier selection.
+        if (!Params().IsStakeModifierV2(nHeight)) {
+            READWRITE(nStakeModifier);
+        } else {
+            READWRITE(nStakeModifierV2);
+        }
+
         if (IsProofOfStake()) {
             READWRITE(prevoutStake);
             READWRITE(nStakeTime);

src/chainparams.cpp

@@ -14,6 +14,7 @@
 #include <assert.h>
 
 #include <boost/assign/list_of.hpp>
+#include <limits>
 
 
 struct SeedSpec6 {
@@ -116,6 +117,17 @@ libzerocoin::ZerocoinParams* CChainParams::Zerocoin_Params(bool useModulusV1) co
     return &ZCParamsDec;
 }
 
+bool CChainParams::HasStakeMinAgeOrDepth(const int contextHeight, const uint32_t contextTime,
+        const int utxoFromBlockHeight, const uint32_t utxoFromBlockTime) const
+{
+    // before stake modifier V2, the age required was 60 * 60 (1 hour) / not required on regtest
+    if (!IsStakeModifierV2(contextHeight))
+        return (NetworkID() == CBaseChainParams::REGTEST || (utxoFromBlockTime + 3600 <= contextTime));
+
+    // after stake modifier V2, we require the utxo to be nStakeMinDepth deep in the chain
+    return (contextHeight - utxoFromBlockHeight >= nStakeMinDepth);
+}
+
 class CMainParams : public CChainParams
 {
 public:
@@ -141,10 +153,11 @@ class CMainParams : public CChainParams
         nRejectBlockOutdatedMajority = 10260; // 95%
         nToCheckBlockUpgradeMajority = 10800; // Approximate expected amount of blocks in 7 days (1440*7.5)
         nMinerThreads = 0;
-        nTargetTimespan = 1 * 60; // PIVX: 1 minute
-        nTargetSpacing = 1 * 60;  // PIVX: 1 minute
+        nTargetSpacing = 1 * 60;        // 1 minute
         nMaturity = 100;
-        nStakeMinAge = 60 * 60;   // PIVX: 1 hour
+        nStakeMinDepth = 600;
+        nFutureTimeDriftPoW = 7200;
+        nFutureTimeDriftPoS = 180;
         nMasternodeCountDrift = 20;
         nMaxMoneyOut = 21000000 * COIN;
 
@@ -165,7 +178,7 @@ class CMainParams : public CChainParams
         nBlockDoubleAccumulated = 1050010;
         nEnforceNewSporkKey = 1525158000; //!> Sporks signed after (GMT): Tuesday, May 1, 2018 7:00:00 AM GMT must use the new spork key
         nRejectOldSporkKey = 1527811200; //!> Fully reject old spork key after (GMT): Friday, June 1, 2018 12:00:00 AM
-
+        nBlockStakeModifierlV2 = 1967000;
         // Public coin spend enforcement
         nPublicZCSpends = 1880000;
 
@@ -256,6 +269,7 @@ class CMainParams : public CChainParams
     {
         return data;
     }
+
 };
 static CMainParams mainParams;
 
@@ -279,12 +293,12 @@ class CTestNetParams : public CMainParams
         nRejectBlockOutdatedMajority = 5472; // 95%
         nToCheckBlockUpgradeMajority = 5760; // 4 days
         nMinerThreads = 0;
-        nTargetTimespan = 1 * 60; // PIVX: 1 day
         nTargetSpacing = 1 * 60;  // PIVX: 1 minute
         nLastPOWBlock = 200;
         nPivxBadBlockTime = 1489001494; // Skip nBit validation of Block 259201 per PR #915
         nPivxBadBlocknBits = 0x1e0a20bd; // Skip nBit validation of Block 201 per PR #915
         nMaturity = 15;
+        nStakeMinDepth = 100;
         nMasternodeCountDrift = 4;
         nModifierUpdateBlock = 51197; //approx Mon, 17 Apr 2017 04:00:00 GMT
         nMaxMoneyOut = 43199500 * COIN;
@@ -299,7 +313,7 @@ class CTestNetParams : public CMainParams
         nBlockZerocoinV2 = 444020; //!> The block that zerocoin v2 becomes active
         nEnforceNewSporkKey = 1521604800; //!> Sporks signed after Wednesday, March 21, 2018 4:00:00 AM GMT must use the new spork key
         nRejectOldSporkKey = 1522454400; //!> Reject old spork key after Saturday, March 31, 2018 12:00:00 AM GMT
-
+        nBlockStakeModifierlV2 = 1214000;
         // Public coin spend enforcement
         nPublicZCSpends = 1106100;
 
@@ -377,12 +391,11 @@ class CRegTestParams : public CTestNetParams
         nRejectBlockOutdatedMajority = 950;
         nToCheckBlockUpgradeMajority = 1000;
         nMinerThreads = 1;
-        nTargetTimespan = 24 * 60 * 60; // PIVX: 1 day
         nTargetSpacing = 1 * 60;        // PIVX: 1 minutes
         bnProofOfWorkLimit = ~uint256(0) >> 1;
         nLastPOWBlock = 250;
         nMaturity = 100;
-        nStakeMinAge = 0;
+        nStakeMinDepth = 0;
         nMasternodeCountDrift = 4;
         nModifierUpdateBlock = 0; //approx Mon, 17 Apr 2017 04:00:00 GMT
         nMaxMoneyOut = 43199500 * COIN;
@@ -393,7 +406,7 @@ class CRegTestParams : public CTestNetParams
         nBlockRecalculateAccumulators = 999999999; //Trigger a recalculation of accumulators
         nBlockFirstFraudulent = 999999999; //First block that bad serials emerged
         nBlockLastGoodCheckpoint = 999999999; //Last valid accumulator checkpoint
-
+        nBlockStakeModifierlV2 = std::numeric_limits<int>::max(); // max integer value (never switch on regtest)
         // Public coin spend enforcement
         nPublicZCSpends = 350;
 
@@ -470,7 +483,6 @@ class CUnitTestParams : public CMainParams, public CModifiableParams
 };
 static CUnitTestParams unitTestParams;
 
-
 static CChainParams* pCurrentParams = 0;
 
 CModifiableParams* ModifiableParams()

src/chainparams.h

@@ -56,7 +56,6 @@ class CChainParams
     int RejectBlockOutdatedMajority() const { return nRejectBlockOutdatedMajority; }
     int ToCheckBlockUpgradeMajority() const { return nToCheckBlockUpgradeMajority; }
     int MaxReorganizationDepth() const { return nMaxReorganizationDepth; }
-    int StakeMinAge() const { return nStakeMinAge; }
 
     /** Used if GenerateBitcoins is called with a negative number of threads */
     int DefaultMinerThreads() const { return nMinerThreads; }
@@ -73,10 +72,19 @@ class CChainParams
     bool SkipProofOfWorkCheck() const { return fSkipProofOfWorkCheck; }
     /** Make standard checks */
     bool RequireStandard() const { return fRequireStandard; }
-    int64_t TargetTimespan() const { return nTargetTimespan; }
     int64_t TargetSpacing() const { return nTargetSpacing; }
-    int64_t Interval() const { return nTargetTimespan / nTargetSpacing; }
+
+    /** returns the coinbase maturity **/
     int COINBASE_MATURITY() const { return nMaturity; }
+
+    /** returns the coinstake maturity (min depth required) **/
+    int COINSTAKE_MIN_DEPTH() const { return nStakeMinDepth; }
+    bool HasStakeMinAgeOrDepth(const int contextHeight, const uint32_t contextTime, const int utxoFromBlockHeight, const uint32_t utxoFromBlockTime) const;
+
+    /** returns the max future time (and drift in seconds) allowed for a block in the future **/
+    int FutureBlockTimeDrift(const bool isPoS) const { return isPoS ? nFutureTimeDriftPoS : nFutureTimeDriftPoW; }
+    uint32_t MaxFutureBlockTime(uint32_t time, const bool isPoS) const { return time + FutureBlockTimeDrift(isPoS); }
+
     CAmount MaxMoneyOut() const { return nMaxMoneyOut; }
     /** The masternode count that we will allow the see-saw reward payments to be off by */
     int MasternodeCountDrift() const { return nMasternodeCountDrift; }
@@ -131,6 +139,7 @@ class CChainParams
     int Zerocoin_StartTime() const { return nZerocoinStartTime; }
     int Block_Enforce_Invalid() const { return nBlockEnforceInvalidUTXO; }
     int Zerocoin_Block_V2_Start() const { return nBlockZerocoinV2; }
+    bool IsStakeModifierV2(const int nHeight) const { return nHeight >= nBlockStakeModifierlV2; }
 
     // fake serial attack
     int Zerocoin_Block_EndFakeSerial() const { return nFakeSerialBlockheightEnd; }
@@ -150,19 +159,21 @@ class CChainParams
     std::vector<unsigned char> vAlertPubKey;
     int nDefaultPort;
     uint256 bnProofOfWorkLimit;
-    int nStakeMinAge;
     int nMaxReorganizationDepth;
     int nSubsidyHalvingInterval;
     int nEnforceBlockUpgradeMajority;
     int nRejectBlockOutdatedMajority;
     int nToCheckBlockUpgradeMajority;
-    int64_t nTargetTimespan;
     int64_t nTargetSpacing;
     int nLastPOWBlock;
     int64_t nPivxBadBlockTime;
     unsigned int nPivxBadBlocknBits;
     int nMasternodeCountDrift;
     int nMaturity;
+    int nStakeMinDepth;
+    int nFutureTimeDriftPoW;
+    int nFutureTimeDriftPoS;
+
     int nModifierUpdateBlock;
     CAmount nMaxMoneyOut;
     int nMinerThreads;
@@ -211,6 +222,7 @@ class CChainParams
     int nBlockZerocoinV2;
     int nBlockDoubleAccumulated;
     int nPublicZCSpends;
+    int nBlockStakeModifierlV2;
 
     // fake serial attack
     int nFakeSerialBlockheightEnd = 0;