From 32559ccad1e0519ce1decc4b90df021fe215a811 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?P=C3=A9ter=20Szil=C3=A1gyi?= <peterke@gmail.com>
Date: Thu, 2 Jun 2016 15:54:07 +0300
Subject: [PATCH] eth: don't accept transactions until we sync up with the
 network

---
 eth/handler.go       | 14 ++++++++++----
 eth/protocol_test.go |  1 +
 eth/sync.go          |  2 ++
 3 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/eth/handler.go b/eth/handler.go
index 58869a2ee..1e4dc1289 100644
--- a/eth/handler.go
+++ b/eth/handler.go
@@ -59,7 +59,9 @@ type blockFetcherFn func([]common.Hash) error
 type ProtocolManager struct {
 	networkId int
 
-	fastSync   uint32
+	fastSync uint32 // Flag whether fast sync is enabled (gets disabled if we already have blocks)
+	synced   uint32 // Flag whether we're considered synchronised (enables transaction processing)
+
 	txpool     txPool
 	blockchain *core.BlockChain
 	chaindb    ethdb.Database
@@ -161,7 +163,11 @@ func NewProtocolManager(config *core.ChainConfig, fastSync bool, networkId int,
 	heighter := func() uint64 {
 		return blockchain.CurrentBlock().NumberU64()
 	}
-	manager.fetcher = fetcher.New(blockchain.GetBlock, validator, manager.BroadcastBlock, heighter, manager.insertChain, manager.removePeer)
+	inserter := func(blocks types.Blocks) (int, error) {
+		atomic.StoreUint32(&manager.synced, 1) // Mark initial sync done on any fetcher import
+		return manager.insertChain(blocks)
+	}
+	manager.fetcher = fetcher.New(blockchain.GetBlock, validator, manager.BroadcastBlock, heighter, inserter, manager.removePeer)
 
 	if blockchain.Genesis().Hash().Hex() == defaultGenesisHash && networkId == 1 {
 		glog.V(logger.Debug).Infoln("Bad Block Reporting is enabled")
@@ -698,8 +704,8 @@ func (pm *ProtocolManager) handleMsg(p *peer) error {
 		}
 
 	case msg.Code == TxMsg:
-		// Transactions arrived, make sure we have a valid chain to handle them
-		if atomic.LoadUint32(&pm.fastSync) == 1 {
+		// Transactions arrived, make sure we have a valid and fresh chain to handle them
+		if atomic.LoadUint32(&pm.synced) == 0 {
 			break
 		}
 		// Transactions can be processed, parse all of them and deliver to the pool
diff --git a/eth/protocol_test.go b/eth/protocol_test.go
index 0a82e2e79..f860d0a35 100644
--- a/eth/protocol_test.go
+++ b/eth/protocol_test.go
@@ -97,6 +97,7 @@ func TestRecvTransactions63(t *testing.T) { testRecvTransactions(t, 63) }
 func testRecvTransactions(t *testing.T, protocol int) {
 	txAdded := make(chan []*types.Transaction)
 	pm := newTestProtocolManagerMust(t, false, 0, nil, txAdded)
+	pm.synced = 1 // mark synced to accept transactions
 	p, _ := newTestPeer("peer", protocol, pm, true)
 	defer pm.Stop()
 	defer p.close()
diff --git a/eth/sync.go b/eth/sync.go
index 4b16c1322..52f7e90e7 100644
--- a/eth/sync.go
+++ b/eth/sync.go
@@ -174,6 +174,8 @@ func (pm *ProtocolManager) synchronise(peer *peer) {
 	if err := pm.downloader.Synchronise(peer.id, peer.Head(), peer.Td(), mode); err != nil {
 		return
 	}
+	atomic.StoreUint32(&pm.synced, 1) // Mark initial sync done
+
 	// If fast sync was enabled, and we synced up, disable it
 	if atomic.LoadUint32(&pm.fastSync) == 1 {
 		// Disable fast sync if we indeed have something in our chain