MWEB: Consensus params

src/chainparams.cpp

@@ -91,6 +91,11 @@ public:
         consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nStartHeight = 2161152; // End November 2021
         consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nTimeoutHeight = 2370816; // 364 days later
 
+        // Deployment of MWEB (LIP-0002, LIP-0003, and LIP-0004)
+        consensus.vDeployments[Consensus::DEPLOYMENT_MWEB].bit = 4;
+        consensus.vDeployments[Consensus::DEPLOYMENT_MWEB].nStartHeight = 2217600; // End Feb 2022
+        consensus.vDeployments[Consensus::DEPLOYMENT_MWEB].nTimeoutHeight = 2427264; // 364 days later
+
         consensus.nMinimumChainWork = uint256S("0x000000000000000000000000000000000000000000000702edaa57d42a9fd9e2");
         consensus.defaultAssumeValid = uint256S("0x62e2e3d21343a00994d38a63524867507dbeee6850e8fbf02e9c47a3ccf82f24"); // 2186382
 
@@ -205,6 +210,11 @@ public:
         consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nStartTime = 1619222400; // April 24th, 2021
         consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nTimeout = 1628640000; // August 11th, 2021
 
+        // Deployment of MWEB (LIP-0002, LIP-0003, and LIP-0004)
+        consensus.vDeployments[Consensus::DEPLOYMENT_MWEB].bit = 4;
+        consensus.vDeployments[Consensus::DEPLOYMENT_MWEB].nStartHeight = 2209536; // Jan/Feb 2022
+        consensus.vDeployments[Consensus::DEPLOYMENT_MWEB].nTimeoutHeight = 2419200; // 364 days later
+
         consensus.nMinimumChainWork = uint256S("0x000000000000000000000000000000000000000000000000004260a1758f04aa");
         consensus.defaultAssumeValid = uint256S("0x4a280c0e150e3b74ebe19618e6394548c8a39d5549fd9941b9c431c73822fbd5"); // 1737876
 
@@ -296,6 +306,11 @@ public:
         consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nStartTime = Consensus::BIP9Deployment::ALWAYS_ACTIVE;
         consensus.vDeployments[Consensus::DEPLOYMENT_TAPROOT].nTimeout = Consensus::BIP9Deployment::NO_TIMEOUT;
 
+        // Deployment of MWEB (LIP-0002 and LIP-0003)
+        consensus.vDeployments[Consensus::DEPLOYMENT_MWEB].bit = 4;
+        consensus.vDeployments[Consensus::DEPLOYMENT_MWEB].nStartTime = 1601450001; // September 30, 2020
+        consensus.vDeployments[Consensus::DEPLOYMENT_MWEB].nTimeout = Consensus::BIP9Deployment::NO_TIMEOUT;
+
         consensus.nMinimumChainWork = uint256{};
         consensus.defaultAssumeValid = uint256{};
 

src/consensus/params.h

@@ -15,6 +15,7 @@ enum DeploymentPos
 {
     DEPLOYMENT_TESTDUMMY,
     DEPLOYMENT_TAPROOT, // Deployment of Schnorr/Taproot (BIPs 340-342)
+    DEPLOYMENT_MWEB, // Deployment of MWEB (LIPs 0002-0004)
     // NOTE: Also add new deployments to VersionBitsDeploymentInfo in versionbits.cpp
     MAX_VERSION_BITS_DEPLOYMENTS
 };

src/rpc/blockchain.cpp

@@ -1362,6 +1362,7 @@ RPCHelpMan getblockchaininfo()
     BuriedForkDescPushBack(softforks, "segwit", consensusParams.SegwitHeight);
     VBSoftForkDescPushBack(softforks, "testdummy", consensusParams, Consensus::DEPLOYMENT_TESTDUMMY);
     VBSoftForkDescPushBack(softforks, "taproot", consensusParams, Consensus::DEPLOYMENT_TAPROOT);
+    VBSoftForkDescPushBack(softforks, "mweb", consensusParams, Consensus::DEPLOYMENT_MWEB);
     obj.pushKV("softforks",             softforks);
 
     obj.pushKV("warnings", GetWarnings(false).original);

src/validation.cpp

@@ -3414,6 +3414,12 @@ bool IsWitnessEnabled(const CBlockIndex* pindexPrev, const Consensus::Params& pa
     return (height >= params.SegwitHeight);
 }
 
+bool IsMWEBEnabled(const CBlockIndex* pindexPrev, const Consensus::Params& params)
+{
+    LOCK(cs_main);
+    return (VersionBitsState(pindexPrev, params, Consensus::DEPLOYMENT_MWEB, versionbitscache) == ThresholdState::ACTIVE);
+}
+
 void UpdateUncommittedBlockStructures(CBlock& block, const CBlockIndex* pindexPrev, const Consensus::Params& consensusParams)
 {
     int commitpos = GetWitnessCommitmentIndex(block);

src/validation.h

@@ -306,6 +306,9 @@ bool TestBlockValidity(BlockValidationState& state, const CChainParams& chainpar
  *  Note that transaction witness validation rules are always enforced when P2SH is enforced. */
 bool IsWitnessEnabled(const CBlockIndex* pindexPrev, const Consensus::Params& params);
 
+/** Check whether MWEB (LIPs 002-004) has activated. */
+bool IsMWEBEnabled(const CBlockIndex* pindexPrev, const Consensus::Params& params);
+
 /** Update uncommitted block structures (currently: only the witness reserved value). This is safe for submitted blocks. */
 void UpdateUncommittedBlockStructures(CBlock& block, const CBlockIndex* pindexPrev, const Consensus::Params& consensusParams);
 

src/versionbits.cpp

@@ -38,7 +38,7 @@ ThresholdState AbstractThresholdConditionChecker::GetStateFor(const CBlockIndex*
             cache[pindexPrev] = ThresholdState::DEFINED;
             break;
         }
-        if (fHeightBased ? (pindexPrev->nHeight + 1) < nHeightStart : pindexPrev->GetMedianTimePast() < nTimeStart) {
+        if (fHeightBased ? ((pindexPrev->nHeight + 1) < nHeightStart) : (pindexPrev->GetMedianTimePast() < nTimeStart)) {
             // Optimization: don't recompute down further, as we know every earlier block will be before the start time
             cache[pindexPrev] = ThresholdState::DEFINED;
             break;
@@ -76,7 +76,7 @@ ThresholdState AbstractThresholdConditionChecker::GetStateFor(const CBlockIndex*
                 }
                 if (count >= nThreshold) {
                     stateNext = ThresholdState::LOCKED_IN;
-                } else if (fHeightBased ? (pindexPrev->nHeight + 1) >= nHeightTimeout : pindexPrev->GetMedianTimePast() >= nTimeTimeout) {
+                } else if (fHeightBased ? ((pindexPrev->nHeight + 1) >= nHeightTimeout) : (pindexPrev->GetMedianTimePast() >= nTimeTimeout)) {
                     stateNext = fHeightBased ? ThresholdState::LOCKED_IN : ThresholdState::FAILED;
                 }
                 break;

src/versionbitsinfo.cpp

@@ -15,4 +15,8 @@ const struct VBDeploymentInfo VersionBitsDeploymentInfo[Consensus::MAX_VERSION_B
         /*.name =*/ "taproot",
         /*.gbt_force =*/ true,
     },
+    {
+        /*.name =*/ "mweb",
+        /*.gbt_force =*/ true,
+    },
 };