From 98c4c9327bb5a0e10a42b493d331a330ad166bf7 Mon Sep 17 00:00:00 2001
From: Arvid Norberg <arvid@libtorrent.org>
Date: Thu, 28 Aug 2014 02:06:21 +0000
Subject: [PATCH] merged change from RC_1_0

---
 ChangeLog                    |  1 +
 src/kademlia/dos_blocker.cpp | 24 +++++++++++++-----------
 2 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 624cef58b..6ad33cd93 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -27,6 +27,7 @@
 	* almost completely changed the storage interface (for custom storage)
 	* added support for hashing pieces in multiple threads
 
+	* make DHT DOS detection more forgiving to bursts
 	* support IPv6 multicast in local service discovery
 	* simplify CAS function in DHT put
 	* support IPv6 traffic class (via the TOS setting)
diff --git a/src/kademlia/dos_blocker.cpp b/src/kademlia/dos_blocker.cpp
index 93f2b71ba..daaf4b47c 100644
--- a/src/kademlia/dos_blocker.cpp
+++ b/src/kademlia/dos_blocker.cpp
@@ -57,40 +57,42 @@ namespace libtorrent { namespace dht
 				break;
 			}
 			if (i->count < min->count) min = i;
+			else if (i->count == min->count
+				&& i->limit < min->limit) min = i;
 		}
 
 		if (match)
 		{
 			++match->count;
-			if (match->count >= 20)
+			if (match->count >= 50)
 			{
 				if (now < match->limit)
 				{
-#ifdef TORRENT_DHT_VERBOSE_LOGGING
-					if (match->count == 20)
+					if (match->count == 50)
 					{
+#ifdef TORRENT_DHT_VERBOSE_LOGGING
 						TORRENT_LOG(dht_tracker) << " BANNING PEER [ ip: "
-							<< addr << " time: " << total_milliseconds((now - match->limit) + seconds(5)) / 1000.f
+							<< addr << " time: " << total_milliseconds((now - match->limit) + seconds(10)) / 1000.f
 							<< " count: " << match->count << " ]";
-					}
 #endif
+						// we've received 50 messages in less than 10 seconds from
+						// this node. Ignore it until it's silent for 5 minutes
+						match->limit = now + minutes(5);
+					}
 		
-					// we've received 20 messages in less than 5 seconds from
-					// this node. Ignore it until it's silent for 5 minutes
-					match->limit = now + minutes(5);
 					return false;
 				}
 
 				// we got 50 messages from this peer, but it was in
-				// more than 5 seconds. Reset the counter and the timer
+				// more than 10 seconds. Reset the counter and the timer
 				match->count = 0;
-				match->limit = now + seconds(5);
+				match->limit = now + seconds(10);
 			}
 		}
 		else
 		{
 			min->count = 1;
-			min->limit = now + seconds(5);
+			min->limit = now + seconds(10);
 			min->src = addr;
 		}
 		return true;