1 files changed, 57 insertions, 0 deletions
diff --git a/src/consensus/tx_check.cpp b/src/consensus/tx_check.cpp
new file mode 100644
index 0000000000..23ed3ecb53
--- /dev/null
+++ b/src/consensus/tx_check.cpp
@@ -0,0 +1,57 @@
+// Copyright (c) 2017-2018 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <consensus/tx_check.h>
+
+#include <primitives/transaction.h>
+#include <consensus/validation.h>
+
+bool CheckTransaction(const CTransaction& tx, CValidationState &state, bool fCheckDuplicateInputs)
+{
+    // Basic checks that don't depend on any context
+    if (tx.vin.empty())
+        return state.Invalid(ValidationInvalidReason::CONSENSUS, false, REJECT_INVALID, "bad-txns-vin-empty");
+    if (tx.vout.empty())
+        return state.Invalid(ValidationInvalidReason::CONSENSUS, false, REJECT_INVALID, "bad-txns-vout-empty");
+    // Size limits (this doesn't take the witness into account, as that hasn't been checked for malleability)
+    if (::GetSerializeSize(tx, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS) * WITNESS_SCALE_FACTOR > MAX_BLOCK_WEIGHT)
+        return state.Invalid(ValidationInvalidReason::CONSENSUS, false, REJECT_INVALID, "bad-txns-oversize");
+
+    // Check for negative or overflow output values
+    CAmount nValueOut = 0;
+    for (const auto& txout : tx.vout)
+    {
+        if (txout.nValue < 0)
+            return state.Invalid(ValidationInvalidReason::CONSENSUS, false, REJECT_INVALID, "bad-txns-vout-negative");
+        if (txout.nValue > MAX_MONEY)
+            return state.Invalid(ValidationInvalidReason::CONSENSUS, false, REJECT_INVALID, "bad-txns-vout-toolarge");
+        nValueOut += txout.nValue;
+        if (!MoneyRange(nValueOut))
+            return state.Invalid(ValidationInvalidReason::CONSENSUS, false, REJECT_INVALID, "bad-txns-txouttotal-toolarge");
+    }
+
+    // Check for duplicate inputs - note that this check is slow so we skip it in CheckBlock
+    if (fCheckDuplicateInputs) {
+        std::set<COutPoint> vInOutPoints;
+        for (const auto& txin : tx.vin)
+        {
+            if (!vInOutPoints.insert(txin.prevout).second)
+                return state.Invalid(ValidationInvalidReason::CONSENSUS, false, REJECT_INVALID, "bad-txns-inputs-duplicate");
+        }
+    }
+
+    if (tx.IsCoinBase())
+    {
+        if (tx.vin[0].scriptSig.size() < 2 || tx.vin[0].scriptSig.size() > 100)
+            return state.Invalid(ValidationInvalidReason::CONSENSUS, false, REJECT_INVALID, "bad-cb-length");
+    }
+    else
+    {
+        for (const auto& txin : tx.vin)
+            if (txin.prevout.IsNull())
+                return state.Invalid(ValidationInvalidReason::CONSENSUS, false, REJECT_INVALID, "bad-txns-prevout-null");
+    }
+
+    return true;
+}