1 files changed, 34 insertions, 6 deletions

diff --git a/src/script/interpreter.cpp b/src/script/interpreter.cpp
index 182f4a3327..e0d193fa38 100644
--- a/src/script/interpreter.cpp
+++ b/src/script/interpreter.cpp
@@ -250,6 +250,34 @@ bool static CheckMinimalPush(const valtype& data, opcodetype opcode) {
     return true;
 }
 
+int FindAndDelete(CScript& script, const CScript& b)
+{
+    int nFound = 0;
+    if (b.empty())
+        return nFound;
+    CScript result;
+    CScript::const_iterator pc = script.begin(), pc2 = script.begin(), end = script.end();
+    opcodetype opcode;
+    do
+    {
+        result.insert(result.end(), pc2, pc);
+        while (static_cast<size_t>(end - pc) >= b.size() && std::equal(b.begin(), b.end(), pc))
+        {
+            pc = pc + b.size();
+            ++nFound;
+        }
+        pc2 = pc;
+    }
+    while (script.GetOp(pc, opcode));
+
+    if (nFound > 0) {
+        result.insert(result.end(), pc2, end);
+        script = std::move(result);
+    }
+
+    return nFound;
+}
+
 bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript& script, unsigned int flags, const BaseSignatureChecker& checker, SigVersion sigversion, ScriptError* serror)
 {
     static const CScriptNum bnZero(0);
@@ -891,7 +919,7 @@ bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript&
 
                     // Drop the signature in pre-segwit scripts but not segwit scripts
                     if (sigversion == SigVersion::BASE) {
-                        scriptCode.FindAndDelete(CScript(vchSig));
+                        FindAndDelete(scriptCode, CScript(vchSig));
                     }
 
                     if (!CheckSignatureEncoding(vchSig, flags, serror) || !CheckPubKeyEncoding(vchPubKey, flags, sigversion, serror)) {
@@ -955,7 +983,7 @@ bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript&
                     {
                         valtype& vchSig = stacktop(-isig-k);
                         if (sigversion == SigVersion::BASE) {
-                            scriptCode.FindAndDelete(CScript(vchSig));
+                            FindAndDelete(scriptCode, CScript(vchSig));
                         }
                     }
 
@@ -1361,7 +1389,7 @@ static bool VerifyWitnessProgram(const CScriptWitness& witness, int witversion,
     CScript scriptPubKey;
 
     if (witversion == 0) {
-        if (program.size() == 32) {
+        if (program.size() == WITNESS_V0_SCRIPTHASH_SIZE) {
             // Version 0 segregated witness program: SHA256(CScript) inside the program, CScript + inputs in witness
             if (witness.stack.size() == 0) {
                 return set_error(serror, SCRIPT_ERR_WITNESS_PROGRAM_WITNESS_EMPTY);
@@ -1373,7 +1401,7 @@ static bool VerifyWitnessProgram(const CScriptWitness& witness, int witversion,
             if (memcmp(hashScriptPubKey.begin(), program.data(), 32)) {
                 return set_error(serror, SCRIPT_ERR_WITNESS_PROGRAM_MISMATCH);
             }
-        } else if (program.size() == 20) {
+        } else if (program.size() == WITNESS_V0_KEYHASH_SIZE) {
             // Special case for pay-to-pubkeyhash; signature + pubkey in witness
             if (witness.stack.size() != 2) {
                 return set_error(serror, SCRIPT_ERR_WITNESS_PROGRAM_MISMATCH); // 2 items in witness
@@ -1530,10 +1558,10 @@ bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, const C
 size_t static WitnessSigOps(int witversion, const std::vector<unsigned char>& witprogram, const CScriptWitness& witness, int flags)
 {
     if (witversion == 0) {
-        if (witprogram.size() == 20)
+        if (witprogram.size() == WITNESS_V0_KEYHASH_SIZE)
             return 1;
 
-        if (witprogram.size() == 32 && witness.stack.size() > 0) {
+        if (witprogram.size() == WITNESS_V0_SCRIPTHASH_SIZE && witness.stack.size() > 0) {
             CScript subscript(witness.stack.back().begin(), witness.stack.back().end());
             return subscript.GetSigOpCount(true);
         }