From e4ba9f6b0402cf7a2ad0d74f617c434a26c6e124 Mon Sep 17 00:00:00 2001
From: Suhas Daftuar <sdaftuar@gmail.com>
Date: Thu, 7 Apr 2016 14:33:08 -0400
Subject: [PATCH] Version 2 transactions remain non-standard until CSV
 activates

Before activation, such transactions might not be mined, so don't
allow into the mempool.
---
 src/main.cpp | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/main.cpp b/src/main.cpp
index a9f104c88b..f5c7e11d6e 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1025,6 +1025,14 @@ bool AcceptToMemoryPoolWorker(CTxMemPool& pool, CValidationState& state, const C
     if (fRequireStandard && !IsStandardTx(tx, reason))
         return state.DoS(0, false, REJECT_NONSTANDARD, reason);
 
+    // Don't relay version 2 transactions until CSV is active, and we can be
+    // sure that such transactions will be mined (unless we're on
+    // -testnet/-regtest).
+    const CChainParams& chainparams = Params();
+    if (fRequireStandard && tx.nVersion >= 2 && VersionBitsTipState(chainparams.GetConsensus(), Consensus::DEPLOYMENT_CSV) != THRESHOLD_ACTIVE) {
+        return state.DoS(0, false, REJECT_NONSTANDARD, "premature-version2-tx");
+    }
+
     // Only accept nLockTime-using transactions that can be mined in the next
     // block; we don't want our mempool filled up with transactions that can't
     // be mined yet.