From 4dde5a16e6fd9470843d45871ae03bc3e2fd43d4 Mon Sep 17 00:00:00 2001
From: Captain <captain@dero.io>
Date: Fri, 3 Jul 2020 12:43:11 +0000
Subject: [PATCH] P2P memory consuming bug fixed.

---
 p2p/chain_request.go  |  2 +-
 p2p/chain_response.go |  2 +-
 p2p/handshake.go      |  4 +++-
 p2p/peer_pool.go      | 11 +++++++++--
 4 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/p2p/chain_request.go b/p2p/chain_request.go
index 867e7bf..674d520 100644
--- a/p2p/chain_request.go
+++ b/p2p/chain_request.go
@@ -99,7 +99,7 @@ func (connection *Connection) Handle_ChainRequest(buf []byte) {
 		return
 	}
 
-	if len(request.Block_list) != len(request.TopoHeights) {
+	if len(request.Block_list) != len(request.TopoHeights) || len(request.Block_list) > 1024 {
 		rlog.Warnf("Peer chain request has %d block %d topos, therefore invalid", len(request.Block_list), len(request.TopoHeights))
 		connection.Exit()
 		return
diff --git a/p2p/chain_response.go b/p2p/chain_response.go
index 7829be3..7be31e1 100644
--- a/p2p/chain_response.go
+++ b/p2p/chain_response.go
@@ -62,7 +62,7 @@ func (connection *Connection) Handle_ChainResponse(buf []byte) {
 	}
 
 	// we were expecting something else ban
-	if len(response.Block_list) < 1 {
+	if len(response.Block_list) < 1 || len(response.TopBlocks) > 100 {
 		rlog.Warnf("Malformed chain response  %s", err, connection.logid)
 		connection.Exit()
 		return
diff --git a/p2p/handshake.go b/p2p/handshake.go
index e4f3ec6..fdd7b80 100644
--- a/p2p/handshake.go
+++ b/p2p/handshake.go
@@ -181,7 +181,9 @@ func (connection *Connection) Handle_Handshake(buf []byte) {
 	// parse delivered peer list as grey list
 	rlog.Debugf("Peer provides %d peers", len(handshake.PeerList))
 	for i := range handshake.PeerList {
-		Peer_Add(&Peer{Address: handshake.PeerList[i].Addr})
+        if i < 13 {
+		    Peer_Add(&Peer{Address: handshake.PeerList[i].Addr})
+        }
 	}
 
 	atomic.StoreUint32(&connection.State, ACTIVE)
diff --git a/p2p/peer_pool.go b/p2p/peer_pool.go
index 62e1439..e89253d 100644
--- a/p2p/peer_pool.go
+++ b/p2p/peer_pool.go
@@ -118,11 +118,17 @@ func clean_up() {
 	peer_mutex.Lock()
 	defer peer_mutex.Unlock()
 	for k, v := range peer_map {
-		if v.FailCount >= 16 { // roughly 16 tries, 18 hrs before we discard the peer
+		if v.FailCount >= 8 { // roughly 16 tries, 18 hrs before we discard the peer
 			delete(peer_map, k)
 		}
-	}
+        if v.LastConnected == 0 { // if never connected, purge the peer
+            delete(peer_map, k)
+        }
 
+        if uint64(time.Now().UTC().Unix())  > ( v.LastConnected + 42000) { // purge all peers which were not connected in
+             delete(peer_map, k)
+        }
+	}
 }
 
 // check whether an IP is in the map already
@@ -147,6 +153,7 @@ func GetPeerInList(address string) *Peer {
 
 // add connection to  map
 func Peer_Add(p *Peer) {
+    clean_up();
 	peer_mutex.Lock()
 	defer peer_mutex.Unlock()