policy: Reject transactions with witness before SegWit activates

lateminer · Jan 22, 2024 · 5facf3c · 5facf3c
1 parent 5f77e59
commit 5facf3c
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Showing 3 changed files with 14 additions and 7 deletions.
diff --git a/src/policy/policy.cpp b/src/policy/policy.cpp
@@ -69,7 +69,7 @@ bool IsDust(const CTxOut& txout, const CFeeRate& dustRelayFeeIn)
     return (txout.nValue < GetDustThreshold(txout, dustRelayFeeIn));
 } 
 
-bool IsStandard(const CScript& scriptPubKey, const std::optional<unsigned>& max_datacarrier_bytes, TxoutType& whichType)
+bool IsStandard(const CScript& scriptPubKey, const std::optional<unsigned>& max_datacarrier_bytes, TxoutType& whichType, const bool witnessEnabled)
 {
     std::vector<std::vector<unsigned char> > vSolutions;
     whichType = Solver(scriptPubKey, vSolutions);
@@ -88,12 +88,13 @@ bool IsStandard(const CScript& scriptPubKey, const std::optional<unsigned>& max_
         if (!max_datacarrier_bytes || scriptPubKey.size() > *max_datacarrier_bytes) {
             return false;
         }
+    } else if (!witnessEnabled && (whichType == TxoutType::WITNESS_V0_SCRIPTHASH || whichType == TxoutType::WITNESS_V0_KEYHASH || whichType == TxoutType::WITNESS_V1_TAPROOT || whichType == TxoutType::WITNESS_UNKNOWN)) {
+        return false;
     }
-
     return true;
 }
 
-bool IsStandardTx(const CTransaction& tx, const std::optional<unsigned>& max_datacarrier_bytes, bool permit_bare_multisig, const CFeeRate& dust_relay_fee, std::string& reason)
+bool IsStandardTx(const CTransaction& tx, const std::optional<unsigned>& max_datacarrier_bytes, bool permit_bare_multisig, const CFeeRate& dust_relay_fee, std::string& reason, const bool witnessEnabled)
 {
     if ((!Params().GetConsensus().IsProtocolV3_1(tx.nTime ? (int64_t)tx.nTime : GetAdjustedTimeSeconds()) && (tx.nVersion > TX_MAX_STANDARD_VERSION-1)) || tx.nVersion > TX_MAX_STANDARD_VERSION || tx.nVersion < 1) {
         reason = "version";
@@ -133,7 +134,7 @@ bool IsStandardTx(const CTransaction& tx, const std::optional<unsigned>& max_dat
     unsigned int nDataOut = 0;
     TxoutType whichType;
     for (const CTxOut& txout : tx.vout) {
-        if (!::IsStandard(txout.scriptPubKey, max_datacarrier_bytes, whichType)) {
+        if (!::IsStandard(txout.scriptPubKey, max_datacarrier_bytes, whichType, witnessEnabled)) {
             reason = "scriptpubkey";
             return false;
         }

diff --git a/src/policy/policy.h b/src/policy/policy.h
@@ -102,7 +102,7 @@ CAmount GetDustThreshold(const CTxOut& txout, const CFeeRate& dustRelayFee);
 
 bool IsDust(const CTxOut& txout, const CFeeRate& dustRelayFee);
 
-bool IsStandard(const CScript& scriptPubKey, const std::optional<unsigned>& max_datacarrier_bytes, TxoutType& whichType);
+bool IsStandard(const CScript& scriptPubKey, const std::optional<unsigned>& max_datacarrier_bytes, TxoutType& whichType, const bool witnessEnabled = false);
 
 
 // Changing the default transaction version requires a two step process: first
@@ -114,7 +114,7 @@ static constexpr decltype(CTransaction::nVersion) TX_MAX_STANDARD_VERSION{2};
 * Check for standard transaction types
 * @return True if all outputs (scriptPubKeys) use only standard transaction forms
 */
-bool IsStandardTx(const CTransaction& tx, const std::optional<unsigned>& max_datacarrier_bytes, bool permit_bare_multisig, const CFeeRate& dust_relay_fee, std::string& reason);
+bool IsStandardTx(const CTransaction& tx, const std::optional<unsigned>& max_datacarrier_bytes, bool permit_bare_multisig, const CFeeRate& dust_relay_fee, std::string& reason, const bool witnessEnabled = false);
 /**
 * Check for standard transaction types
 * @param[in] mapInputs       Map of previous transactions that have outputs we're spending

diff --git a/src/validation.cpp b/src/validation.cpp
@@ -715,9 +715,15 @@ bool MemPoolAccept::PreChecks(ATMPArgs& args, Workspace& ws)
     if (m_pool.m_require_standard && tx.nVersion >= TX_MAX_STANDARD_VERSION && !Params().GetConsensus().IsProtocolV3_1(nTimeTx))
 		return state.Invalid(TxValidationResult::TX_NOT_STANDARD, "premature-version2-tx");
 
+    // Reject transactions with witness before segregated witness activates (override with -prematurewitness)
+    bool witnessEnabled = DeploymentActiveAfter(m_active_chainstate.m_chain.Tip(), m_active_chainstate.m_chainman, Consensus::DEPLOYMENT_SEGWIT);
+    if (!gArgs.GetBoolArg("-prematurewitness", false) && tx.HasWitness() && !witnessEnabled) {
+        return state.Invalid(TxValidationResult::TX_NOT_STANDARD, "no-witness-yet");
+    }
+
     // Rather not work on nonstandard transactions (unless -testnet/-regtest)
     std::string reason;
-    if (m_pool.m_require_standard && !IsStandardTx(tx, m_pool.m_max_datacarrier_bytes, m_pool.m_permit_bare_multisig, m_pool.m_dust_relay_feerate, reason)) {
+    if (m_pool.m_require_standard && !IsStandardTx(tx, m_pool.m_max_datacarrier_bytes, m_pool.m_permit_bare_multisig, m_pool.m_dust_relay_feerate, reason, witnessEnabled)) {
         return state.Invalid(TxValidationResult::TX_NOT_STANDARD, reason);
     }