From 33208fb5575d76a19163e830617eaaf32dbacda8 Mon Sep 17 00:00:00 2001
From: Matt Corallo <matt@bluematt.me>
Date: Sat, 30 Jul 2011 23:01:45 +0200
Subject: [PATCH] Check for duplicate txins in CheckTransaction.

---
 src/main.cpp | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/src/main.cpp b/src/main.cpp
index b57974f577..dccc1727f0 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -314,6 +314,15 @@ bool CTransaction::CheckTransaction() const
             return error("CTransaction::CheckTransaction() : txout total out of range");
     }
 
+    // Check for duplicate inputs
+    set<COutPoint> vInOutPoints;
+    BOOST_FOREACH(const CTxIn& txin, vin)
+    {
+        if (vInOutPoints.count(txin.prevout))
+            return false;
+        vInOutPoints.insert(txin.prevout);
+    }
+
     if (IsCoinBase())
     {
         if (vin[0].scriptSig.size() < 2 || vin[0].scriptSig.size() > 100)