Sanity-check script sizes in bitcoin-tx

Author: TheBlueMatt

src/bitcoin-tx.cpp

@@ -387,6 +387,10 @@ static void MutateTxAddOutMultiSig(CMutableTransaction& tx, const std::string& s
         scriptPubKey = GetScriptForWitness(scriptPubKey);
     }
     if (bScriptHash) {
+        if (scriptPubKey.size() > MAX_SCRIPT_ELEMENT_SIZE) {
+            throw std::runtime_error(strprintf(
+                        "redeemScript exceeds size limit: %d > %d", scriptPubKey.size(), MAX_SCRIPT_ELEMENT_SIZE));
+        }
         // Get the ID for the script, and then construct a P2SH destination for it.
         scriptPubKey = GetScriptForDestination(CScriptID(scriptPubKey));
     }
@@ -447,10 +451,19 @@ static void MutateTxAddOutScript(CMutableTransaction& tx, const std::string& str
         bScriptHash = (flags.find("S") != std::string::npos);
     }
 
+    if (scriptPubKey.size() > MAX_SCRIPT_SIZE) {
+        throw std::runtime_error(strprintf(
+                    "script exceeds size limit: %d > %d", scriptPubKey.size(), MAX_SCRIPT_SIZE));
+    }
+
     if (bSegWit) {
         scriptPubKey = GetScriptForWitness(scriptPubKey);
     }
     if (bScriptHash) {
+        if (scriptPubKey.size() > MAX_SCRIPT_ELEMENT_SIZE) {
+            throw std::runtime_error(strprintf(
+                        "redeemScript exceeds size limit: %d > %d", scriptPubKey.size(), MAX_SCRIPT_ELEMENT_SIZE));
+        }
         scriptPubKey = GetScriptForDestination(CScriptID(scriptPubKey));
     }