AreInputsStandard: Return specific reject reasons

luke-jr · luke-jr · commit c59e7166253e · 2017-08-21T20:40:25.000Z
diff --git a/src/policy/policy.cpp b/src/policy/policy.cpp
@@ -160,7 +160,7 @@ bool IsStandardTx(const CTransaction& tx, std::string& reason, const bool witnes
     return true;
 }
 
-bool AreInputsStandard(const CTransaction& tx, const CCoinsViewCache& mapInputs)
+bool AreInputsStandard(const CTransaction& tx, const CCoinsViewCache& mapInputs, const std::string& reason_prefix, std::string& out_reason)
 {
     if (tx.IsCoinBase())
         return true; // Coinbases don't use vin normally
@@ -173,19 +173,26 @@ bool AreInputsStandard(const CTransaction& tx, const CCoinsViewCache& mapInputs)
         txnouttype whichType;
         // get the scriptPubKey corresponding to this input:
         const CScript& prevScript = prev.scriptPubKey;
-        if (!Solver(prevScript, whichType, vSolutions))
+        if (!Solver(prevScript, whichType, vSolutions)) {
+            out_reason = reason_prefix + "script-unknown";
             return false;
+        }
 
         if (whichType == TX_SCRIPTHASH)
         {
             std::vector<std::vector<unsigned char> > stack;
             // convert the scriptSig into a stack, so we can inspect the redeemScript
-            if (!EvalScript(stack, tx.vin[i].scriptSig, SCRIPT_VERIFY_NONE, BaseSignatureChecker(), SIGVERSION_BASE))
+            if (!EvalScript(stack, tx.vin[i].scriptSig, SCRIPT_VERIFY_NONE, BaseSignatureChecker(), SIGVERSION_BASE)) {
+                out_reason = reason_prefix + "scriptsig-failure";
                 return false;
-            if (stack.empty())
+            }
+            if (stack.empty()) {
+                out_reason = reason_prefix + "scriptcheck-missing";
                 return false;
+            }
             CScript subscript(stack.back().begin(), stack.back().end());
             if (subscript.GetSigOpCount(true) > MAX_P2SH_SIGOPS) {
+                out_reason = reason_prefix + "scriptcheck-sigops";
                 return false;
             }
         }
diff --git a/src/policy/policy.h b/src/policy/policy.h
@@ -89,7 +89,13 @@ bool IsStandardTx(const CTransaction& tx, std::string& reason, const bool witnes
      * @param[in] mapInputs    Map of previous transactions that have outputs we're spending
      * @return True if all inputs (scriptSigs) use only standard transaction forms
      */
-bool AreInputsStandard(const CTransaction& tx, const CCoinsViewCache& mapInputs);
+bool AreInputsStandard(const CTransaction& tx, const CCoinsViewCache& mapInputs, const std::string& reason_prefix, std::string& out_reason);
+
+inline bool AreInputsStandard(const CTransaction& tx, const CCoinsViewCache& mapInputs) {
+    std::string reason;
+    return AreInputsStandard(tx, mapInputs, reason, reason);
+}
+
     /**
      * Check if the transaction is over standard P2WSH resources limit:
      * 3600bytes witnessScript size, 80bytes per witness stack element, 100 witness stack elements
diff --git a/src/validation.cpp b/src/validation.cpp
@@ -572,8 +572,9 @@ static bool AcceptToMemoryPoolWorker(const CChainParams& chainparams, CTxMemPool
         }
 
         // Check for non-standard pay-to-script-hash in inputs
-        if (fRequireStandard && !AreInputsStandard(tx, view))
-            return state.Invalid(false, REJECT_NONSTANDARD, "bad-txns-nonstandard-inputs");
+        if (fRequireStandard && !AreInputsStandard(tx, view, "bad-txns-input-", reason)) {
+            return state.Invalid(false, REJECT_NONSTANDARD, reason);
+        }
 
         // Check for non-standard witness in P2WSH
         if (tx.HasWitness() && fRequireStandard && !IsWitnessStandard(tx, view))
