From 4dc668286d8b78a0d2f9d4e66e39bdf1773d4444 Mon Sep 17 00:00:00 2001
From: cryptocode <34946442+cryptocode@users.noreply.github.com>
Date: Mon, 7 Jan 2019 23:52:39 +0100
Subject: [PATCH] Lack of contact timestamping drops peers (#1536)

* Lack of contact timestamping drops peers

* Added test to make sure last_contact is updated
---
 nano/core_test/network.cpp | 33 +++++++++++++++++++++++++++++++++
 nano/node/peers.cpp        | 11 +++++++++++
 2 files changed, 44 insertions(+)

diff --git a/nano/core_test/network.cpp b/nano/core_test/network.cpp
index b6a44572d..0c41cf097 100644
--- a/nano/core_test/network.cpp
+++ b/nano/core_test/network.cpp
@@ -116,6 +116,39 @@ TEST (network, keepalive_ipv4)
 	node1->stop ();
 }
 
+TEST (network, last_contacted)
+{
+	nano::system system (24000, 1);
+	auto list1 (system.nodes[0]->peers.list ());
+	ASSERT_EQ (0, list1.size ());
+	nano::node_init init1;
+	auto node1 (std::make_shared<nano::node> (init1, system.io_ctx, 24001, nano::unique_path (), system.alarm, system.logging, system.work));
+	node1->start ();
+	system.nodes.push_back (node1);
+	node1->send_keepalive (nano::endpoint (boost::asio::ip::address_v4::loopback (), 24000));
+	system.deadline_set (10s);
+
+	// Wait until the handshake is complete
+	while (system.nodes[0]->peers.size () < 1)
+	{
+		ASSERT_NO_ERROR (system.poll ());
+	}
+	ASSERT_EQ (system.nodes[0]->peers.size (), 1);
+
+	// Make sure last_contact gets updated on receiving a non-handshake message
+	auto timestamp_before_keepalive = system.nodes[0]->peers.list_vector (1).front ().last_contact;
+	node1->send_keepalive (nano::endpoint (boost::asio::ip::address_v4::loopback (), 24000));
+	while (system.nodes[0]->stats.count (nano::stat::type::message, nano::stat::detail::keepalive, nano::stat::dir::in) < 2)
+	{
+		ASSERT_NO_ERROR (system.poll ());
+	}
+	ASSERT_EQ (system.nodes[0]->peers.size (), 1);
+	auto timestamp_after_keepalive = system.nodes[0]->peers.list_vector (1).front ().last_contact;
+	ASSERT_GT (timestamp_after_keepalive, timestamp_before_keepalive);
+
+	node1->stop ();
+}
+
 TEST (network, multi_keepalive)
 {
 	nano::system system (24000, 1);
diff --git a/nano/node/peers.cpp b/nano/node/peers.cpp
index 4af128e18..6e70d28bc 100644
--- a/nano/node/peers.cpp
+++ b/nano/node/peers.cpp
@@ -62,6 +62,17 @@ bool nano::peer_container::contacted (nano::endpoint const & endpoint_a, unsigne
 			should_handshake = true;
 		}
 	}
+	else
+	{
+		std::lock_guard<std::mutex> lock (mutex);
+		auto existing (peers.find (endpoint_a));
+		if (existing != peers.end ())
+		{
+			peers.modify (existing, [](nano::peer_information & info) {
+				info.last_contact = std::chrono::steady_clock::now ();
+			});
+		}
+	}
 	return should_handshake;
 }