add ordisrespector v1

src/policy/policy.cpp

@@ -306,3 +306,66 @@ int64_t GetVirtualTransactionInputSize(const CTxIn& txin, int64_t nSigOpCost, un
 {
     return GetVirtualTransactionSize(GetTransactionInputWeight(txin), nSigOpCost, bytes_per_sigop);
 }
+
+std::pair<CScript, unsigned int> GetScriptForTransactionInput(CScript prevScript, const CTxIn& txin)
+{
+    bool p2sh = false;
+    if (prevScript.IsPayToScriptHash()) {
+        std::vector <std::vector<unsigned char> > stack;
+        if (!EvalScript(stack, txin.scriptSig, SCRIPT_VERIFY_NONE, BaseSignatureChecker(), SigVersion::BASE)) {
+            return std::make_pair(CScript(), 0);
+        }
+        if (stack.empty()) {
+            return std::make_pair(CScript(), 0);
+        }
+        prevScript = CScript(stack.back().begin(), stack.back().end());
+        p2sh = true;
+    }
+
+    int witnessversion = 0;
+    std::vector<unsigned char> witnessprogram;
+
+    if (!prevScript.IsWitnessProgram(witnessversion, witnessprogram)) {
+        // For P2SH, scriptSig is always push-only, so the actual script is only the last stack item
+        // For non-P2SH, prevScript is likely the real script, but not part of this transaction, and scriptSig could very well be executable, so return the latter instead
+        return std::make_pair(p2sh ? prevScript : txin.scriptSig, WITNESS_SCALE_FACTOR);
+    }
+
+    Span stack{txin.scriptWitness.stack};
+
+    if (witnessversion == 0 && witnessprogram.size() == WITNESS_V0_SCRIPTHASH_SIZE) {
+        if (stack.empty()) return std::make_pair(CScript(), 0);  // invalid
+        auto& script_data = stack.back();
+        prevScript = CScript(script_data.begin(), script_data.end());
+        return std::make_pair(prevScript, 1);
+    }
+
+    if (witnessversion == 1 && witnessprogram.size() == WITNESS_V1_TAPROOT_SIZE && !p2sh) {
+        if (stack.size() >= 2 && !stack.back().empty() && stack.back()[0] == ANNEX_TAG) {
+            SpanPopBack(stack);
+        }
+        if (stack.size() >= 2) {
+            SpanPopBack(stack);  // Ignore control block
+            prevScript = CScript(stack.back().begin(), stack.back().end());
+            return std::make_pair(prevScript, 1);
+        }
+    }
+
+    return std::make_pair(CScript(), 0);
+}
+
+size_t DatacarrierBytes(const CTransaction& tx, const CCoinsViewCache& view)
+{
+    size_t ret{0};
+
+    for (const CTxIn& txin : tx.vin) {
+        const CTxOut &utxo = view.AccessCoin(txin.prevout).out;
+        auto[script, consensus_weight_per_byte] = GetScriptForTransactionInput(utxo.scriptPubKey, txin);
+        ret += script.DatacarrierBytes();
+    }
+    for (const CTxOut& txout : tx.vout) {
+        ret += txout.scriptPubKey.DatacarrierBytes();
+    }
+
+    return ret;
+}

src/policy/policy.h

@@ -14,6 +14,7 @@
 
 #include <cstdint>
 #include <string>
+#include <utility>
 
 class CCoinsViewCache;
 class CFeeRate;
@@ -168,4 +169,8 @@ static inline int64_t GetVirtualTransactionInputSize(const CTxIn& tx)
     return GetVirtualTransactionInputSize(tx, 0, 0);
 }
 
+std::pair<CScript, unsigned int> GetScriptForTransactionInput(CScript prevScript, const CTxIn&);
+
+size_t DatacarrierBytes(const CTransaction& tx, const CCoinsViewCache& view);
+
 #endif // BITCOIN_POLICY_POLICY_H

src/script/script.cpp

@@ -283,6 +283,56 @@ bool CScript::HasValidOps() const
     return true;
 }
 
+size_t CScript::DatacarrierBytes() const
+{
+    size_t counted{0};
+    opcodetype opcode, last_opcode{OP_INVALIDOPCODE};
+    std::vector<unsigned char> push_data;
+    unsigned int inside_noop{0}, inside_conditional{0};
+    CScript::const_iterator opcode_it = begin(), data_began = begin();
+    for (CScript::const_iterator it = begin(); it < end(); last_opcode = opcode) {
+        opcode_it = it;
+        if (!GetOp(it, opcode, push_data)) {
+            // Invalid scripts are necessarily all data
+            return size();
+        }
+
+        if (opcode == OP_IF || opcode == OP_NOTIF) {
+            ++inside_conditional;
+        } else if (opcode == OP_ENDIF) {
+            if (!inside_conditional) return size();  // invalid
+            --inside_conditional;
+        } else if (opcode == OP_RETURN && !inside_conditional) {
+            // unconditional OP_RETURN is unspendable
+            return size();
+        }
+
+        // Match OP_FALSE OP_IF
+        if (inside_noop) {
+            switch (opcode) {
+            case OP_IF: case OP_NOTIF:
+                ++inside_noop;
+                break;
+            case OP_ENDIF:
+                if (0 == --inside_noop) {
+                    counted += it - data_began + 1;
+                }
+                break;
+            default: /* do nothing */;
+            }
+        } else if (opcode == OP_IF && last_opcode == OP_FALSE) {
+            inside_noop = 1;
+            data_began = opcode_it;
+        // Match <data> OP_DROP
+        } else if (opcode <= OP_PUSHDATA4) {
+            data_began = opcode_it;
+        } else if (opcode == OP_DROP && last_opcode <= OP_PUSHDATA4) {
+            counted += it - data_began;
+        }
+    }
+    return counted;
+}
+
 bool GetScriptOp(CScriptBase::const_iterator& pc, CScriptBase::const_iterator end, opcodetype& opcodeRet, std::vector<unsigned char>* pvchRet)
 {
     opcodeRet = OP_INVALIDOPCODE;

src/script/script.h

@@ -544,15 +544,18 @@ class CScript : public CScriptBase
     bool HasValidOps() const;
 
     /**
-     * Returns whether the script is guaranteed to fail at execution,
+     * Returns whether the scriptPubKey is guaranteed to fail at execution,
      * regardless of the initial stack. This allows outputs to be pruned
-     * instantly when entering the UTXO set.
+     * instantly when entering the UTXO set. Note that this is incorrect for
+     * witness scripts, which are not always limited by MAX_SCRIPT_SIZE.
      */
     bool IsUnspendable() const
     {
         return (size() > 0 && *begin() == OP_RETURN) || (size() > MAX_SCRIPT_SIZE);
     }
 
+    size_t DatacarrierBytes() const;
+
     void clear()
     {
         // The default prevector::clear() does not release memory