Merge pull request #303 from ethcore/ark

Check block parent on import; Peer timeouts

ethcore/src/block_queue.rs

@@ -9,6 +9,7 @@ use engine::Engine;
 use views::*;
 use header::*;
 use service::*;
+use client::BlockStatus;
 
 /// Block queue status
 #[derive(Debug)]
@@ -41,7 +42,7 @@ pub struct BlockQueue {
 	deleting: Arc<AtomicBool>,
 	ready_signal: Arc<QueueSignal>,
 	empty: Arc<Condvar>,
-	processing: HashSet<H256>
+	processing: RwLock<HashSet<H256>>
 }
 
 struct UnVerifiedBlock {
@@ -106,7 +107,7 @@ impl BlockQueue {
 			verification: verification.clone(),
 			verifiers: verifiers,
 			deleting: deleting.clone(),
-			processing: HashSet::new(),
+			processing: RwLock::new(HashSet::new()),
 			empty: empty.clone(),
 		}
 	}
@@ -196,11 +197,22 @@ impl BlockQueue {
 		}
 	}
 
+	/// Check if the block is currently in the queue
+	pub fn block_status(&self, hash: &H256) -> BlockStatus {
+		if self.processing.read().unwrap().contains(&hash) {
+			return BlockStatus::Queued;
+		}
+		if self.verification.lock().unwrap().bad.contains(&hash) {
+			return BlockStatus::Bad;
+		}
+		BlockStatus::Unknown
+	}
+
 	/// Add a block to the queue.
 	pub fn import_block(&mut self, bytes: Bytes) -> ImportResult {
 		let header = BlockView::new(&bytes).header();
 		let h = header.hash();
-		if self.processing.contains(&h) {
+		if self.processing.read().unwrap().contains(&h) {
 			return Err(ImportError::AlreadyQueued);
 		}
 		{
@@ -217,7 +229,7 @@ impl BlockQueue {
 
 		match verify_block_basic(&header, &bytes, self.engine.deref().deref()) {
 			Ok(()) => {
-				self.processing.insert(h.clone());
+				self.processing.write().unwrap().insert(h.clone());
 				self.verification.lock().unwrap().unverified.push_back(UnVerifiedBlock { header: header, bytes: bytes });
 				self.more_to_verify.notify_all();
 				Ok(h)
@@ -235,10 +247,12 @@ impl BlockQueue {
 		let mut verification_lock = self.verification.lock().unwrap();
 		let mut verification = verification_lock.deref_mut();
 		verification.bad.insert(hash.clone());
+		self.processing.write().unwrap().remove(&hash);
 		let mut new_verified = VecDeque::new();
 		for block in verification.verified.drain(..) {
 			if verification.bad.contains(&block.header.parent_hash) {
 				verification.bad.insert(block.header.hash());
+				self.processing.write().unwrap().remove(&block.header.hash());
 			}
 			else {
 				new_verified.push_back(block);
@@ -247,6 +261,15 @@ impl BlockQueue {
 		verification.verified = new_verified;
 	}
 
+	/// Mark given block as processed
+	pub fn mark_as_good(&mut self, hashes: &[H256]) {
+		let mut processing = self.processing.write().unwrap();
+		for h in hashes {
+			processing.remove(&h);
+		}
+		//TODO: reward peers
+	}
+
 	/// Removes up to `max` verified blocks from the queue
 	pub fn drain(&mut self, max: usize) -> Vec<PreVerifiedBlock> {
 		let mut verification = self.verification.lock().unwrap();
@@ -254,7 +277,6 @@ impl BlockQueue {
 		let mut result = Vec::with_capacity(count);
 		for _ in 0..count {
 			let block = verification.verified.pop_front().unwrap();
-			self.processing.remove(&block.header.hash());
 			result.push(block);
 		}
 		self.ready_signal.reset();
@@ -294,6 +316,7 @@ mod tests {
 	use block_queue::*;
 	use tests::helpers::*;
 	use error::*;
+	use views::*;
 
 	fn get_test_queue() -> BlockQueue {
 		let spec = get_test_spec();
@@ -339,11 +362,14 @@ mod tests {
 	#[test]
 	fn returns_ok_for_drained_duplicates() {
 		let mut queue = get_test_queue();
-		if let Err(e) = queue.import_block(get_good_dummy_block()) {
+		let block = get_good_dummy_block();
+		let hash = BlockView::new(&block).header().hash().clone();
+		if let Err(e) = queue.import_block(block) {
 			panic!("error importing block that is valid by definition({:?})", e);
 		}
 		queue.flush();
 		queue.drain(10);
+		queue.mark_as_good(&[ hash ]);
 
 		if let Err(e) = queue.import_block(get_good_dummy_block()) {
 			panic!("error importing block that has already been drained ({:?})", e);

ethcore/src/client.rs

@@ -17,7 +17,7 @@ use verification::*;
 use block::*;
 
 /// General block status
-#[derive(Debug)]
+#[derive(Debug, Eq, PartialEq)]
 pub enum BlockStatus {
 	/// Part of the blockchain.
 	InChain,
@@ -206,6 +206,7 @@ impl Client {
 		let mut bad = HashSet::new();
 		let _import_lock = self.import_lock.lock();
 		let blocks = self.block_queue.write().unwrap().drain(128);
+		let mut good_blocks = Vec::with_capacity(128);
 		for block in blocks {
 			if bad.contains(&block.header.parent_hash) {
 				self.block_queue.write().unwrap().mark_as_bad(&block.header.hash());
@@ -258,6 +259,8 @@ impl Client {
 				break;
 			}
 
+			good_blocks.push(header.hash().clone());
+
 			self.chain.write().unwrap().insert_block(&block.bytes); //TODO: err here?
 			let ancient = if header.number() >= HISTORY { Some(header.number() - HISTORY) } else { None };
 			match result.drain().commit(header.number(), &header.hash(), ancient.map(|n|(n, self.chain.read().unwrap().block_hash(n).unwrap()))) {
@@ -271,6 +274,7 @@ impl Client {
 			trace!(target: "client", "Imported #{} ({})", header.number(), header.hash());
 			ret += 1;
 		}
+		self.block_queue.write().unwrap().mark_as_good(&good_blocks);
 		ret
 	}
 
@@ -325,7 +329,11 @@ impl BlockChainClient for Client {
 	}
 
 	fn block_status(&self, hash: &H256) -> BlockStatus {
-		if self.chain.read().unwrap().is_known(&hash) { BlockStatus::InChain } else { BlockStatus::Unknown }
+		if self.chain.read().unwrap().is_known(&hash) {
+			BlockStatus::InChain 
+		} else { 
+			self.block_queue.read().unwrap().block_status(hash) 
+		}
 	}
 	
 	fn block_total_difficulty(&self, hash: &H256) -> Option<U256> {
@@ -372,6 +380,9 @@ impl BlockChainClient for Client {
 		if self.chain.read().unwrap().is_known(&header.hash()) {
 			return Err(ImportError::AlreadyInChain);
 		}
+		if self.block_status(&header.parent_hash) == BlockStatus::Unknown {
+			return Err(ImportError::UnknownParent);
+		}
 		self.block_queue.write().unwrap().import_block(bytes)
 	}
 

ethcore/src/error.rs

@@ -130,14 +130,16 @@ pub enum BlockError {
 }
 
 #[derive(Debug)]
-/// TODO [arkpar] Please document me
+/// Import to the block queue result
 pub enum ImportError {
-	/// TODO [arkpar] Please document me
+	/// Bad block detected
 	Bad(Option<Error>),
-	/// TODO [arkpar] Please document me
+	/// Already in the block chain
 	AlreadyInChain,
-	/// TODO [arkpar] Please document me
+	/// Already in the block queue
 	AlreadyQueued,
+	/// Unknown parent
+	UnknownParent,
 }
 
 impl From<Error> for ImportError {

sync/Cargo.toml

@@ -13,4 +13,5 @@ ethcore = { path = ".." }
 clippy = "0.0.37"
 log = "0.3"
 env_logger = "0.3"
+time = "0.1.34"
 

sync/src/chain.rs

@@ -22,6 +22,7 @@ use range_collection::{RangeCollection, ToUsize, FromUsize};
 use ethcore::error::*;
 use ethcore::block::Block;
 use io::SyncIo;
+use time;
 
 impl ToUsize for BlockNumber {
 	fn to_usize(&self) -> usize {
@@ -61,6 +62,8 @@ const RECEIPTS_PACKET: u8 = 0x10;
 
 const NETWORK_ID: U256 = ONE_U256; //TODO: get this from parent
 
+const CONNECTION_TIMEOUT_SEC: f64 = 30f64;
+
 struct Header {
 	/// Header data
 	data: Bytes,
@@ -138,6 +141,8 @@ struct PeerInfo {
 	asking: PeerAsking,
 	/// A set of block numbers being requested
 	asking_blocks: Vec<BlockNumber>,
+	/// Request timestamp
+	ask_time: f64,
 }
 
 /// Blockchain sync handler.
@@ -250,6 +255,7 @@ impl ChainSync {
 			genesis: try!(r.val_at(4)),
 			asking: PeerAsking::Nothing,
 			asking_blocks: Vec::new(),
+			ask_time: 0f64,
 		};
 
 		trace!(target: "sync", "New peer {} (protocol: {}, network: {:?}, difficulty: {:?}, latest:{}, genesis:{})", peer_id, peer.protocol_version, peer.network_id, peer.difficulty, peer.latest, peer.genesis);
@@ -408,6 +414,7 @@ impl ChainSync {
 		trace!(target: "sync", "{} -> NewBlock ({})", peer_id, h);
 		let header_view = HeaderView::new(header_rlp.as_raw());
 		// TODO: Decompose block and add to self.headers and self.bodies instead
+		let mut unknown = false;
 		if header_view.number() == From::from(self.last_imported_block + 1) {
 			match io.chain().import_block(block_rlp.as_raw().to_vec()) {
 				Err(ImportError::AlreadyInChain) => {
@@ -416,6 +423,10 @@ impl ChainSync {
 				Err(ImportError::AlreadyQueued) => {
 					trace!(target: "sync", "New block already queued {:?}", h);
 				},
+				Err(ImportError::UnknownParent) => {
+					unknown = true;
+					trace!(target: "sync", "New block with unknown parent {:?}", h);
+				},
 				Ok(_) => {
 					trace!(target: "sync", "New block queued {:?}", h);
 				},
@@ -426,6 +437,9 @@ impl ChainSync {
 			};
 		} 
 		else {
+			unknown = true;
+		}
+		if unknown {
 			trace!(target: "sync", "New block unknown {:?}", h);
 			//TODO: handle too many unknown blocks
 			let difficulty: U256 = try!(r.val_at(1));
@@ -795,6 +809,7 @@ impl ChainSync {
 			Ok(_) => {
 				let mut peer = self.peers.get_mut(&peer_id).unwrap();
 				peer.asking = asking;
+				peer.ask_time = time::precise_time_s();
 			}
 		}
 	}
@@ -969,6 +984,16 @@ impl ChainSync {
 		})
 	}
 
+	/// Handle peer timeouts
+	pub fn maintain_peers(&self, io: &mut SyncIo) {
+		let tick = time::precise_time_s();
+		for (peer_id, peer) in &self.peers {
+			if peer.asking != PeerAsking::Nothing && (tick - peer.ask_time) > CONNECTION_TIMEOUT_SEC {
+				io.disconnect_peer(*peer_id);
+			}
+		}
+	}
+
 	/// Maintain other peers. Send out any new blocks and transactions
 	pub fn _maintain_sync(&mut self, _io: &mut SyncIo) {
 	}

sync/src/io.rs

@@ -9,6 +9,8 @@ use ethcore::service::SyncMessage;
 pub trait SyncIo {
 	/// Disable a peer
 	fn disable_peer(&mut self, peer_id: PeerId);
+	/// Disconnect peer
+	fn disconnect_peer(&mut self, peer_id: PeerId);
 	/// Respond to current request with a packet. Can be called from an IO handler for incoming packet.
 	fn respond(&mut self, packet_id: PacketId, data: Vec<u8>) -> Result<(), UtilError>;
 	/// Send a packet to a peer.
@@ -42,6 +44,10 @@ impl<'s, 'h> SyncIo for NetSyncIo<'s, 'h> {
 		self.network.disable_peer(peer_id);
 	}
 
+	fn disconnect_peer(&mut self, peer_id: PeerId) {
+		self.network.disconnect_peer(peer_id);
+	}
+
 	fn respond(&mut self, packet_id: PacketId, data: Vec<u8>) -> Result<(), UtilError>{
 		self.network.respond(packet_id, data)
 	}

sync/src/lib.rs

@@ -33,11 +33,13 @@ extern crate log;
 extern crate ethcore_util as util;
 extern crate ethcore;
 extern crate env_logger;
+extern crate time;
 
 use std::ops::*;
 use std::sync::*;
 use ethcore::client::Client;
 use util::network::{NetworkProtocolHandler, NetworkService, NetworkContext, PeerId};
+use util::io::TimerToken;
 use chain::ChainSync;
 use ethcore::service::SyncMessage;
 use io::NetSyncIo;
@@ -87,7 +89,8 @@ impl EthSync {
 }
 
 impl NetworkProtocolHandler<SyncMessage> for EthSync {
-	fn initialize(&self, _io: &NetworkContext<SyncMessage>) {
+	fn initialize(&self, io: &NetworkContext<SyncMessage>) {
+		io.register_timer(0, 1000).expect("Error registering sync timer");
 	}
 
 	fn read(&self, io: &NetworkContext<SyncMessage>, peer: &PeerId, packet_id: u8, data: &[u8]) {
@@ -101,6 +104,10 @@ impl NetworkProtocolHandler<SyncMessage> for EthSync {
 	fn disconnected(&self, io: &NetworkContext<SyncMessage>, peer: &PeerId) {
 		self.sync.write().unwrap().on_peer_aborting(&mut NetSyncIo::new(io, self.chain.deref()), *peer);
 	}
+
+	fn timeout(&self, io: &NetworkContext<SyncMessage>, _timer: TimerToken) {
+		self.sync.write().unwrap().maintain_peers(&mut NetSyncIo::new(io, self.chain.deref()));
+	}
 }
 
 

sync/src/tests.rs

@@ -209,6 +209,9 @@ impl<'p> SyncIo for TestIo<'p> {
 	fn disable_peer(&mut self, _peer_id: PeerId) {
 	}
 
+	fn disconnect_peer(&mut self, _peer_id: PeerId) {
+	}
+
 	fn respond(&mut self, packet_id: PacketId, data: Vec<u8>) -> Result<(), UtilError> {
 		self.queue.push_back(TestPacket {
 			data: data,

util/src/network/connection.rs

@@ -207,6 +207,12 @@ pub struct EncryptedConnection {
 }
 
 impl EncryptedConnection {
+	
+	/// Get socket token 
+	pub fn token(&self) -> StreamToken {
+		self.connection.token
+	}
+
 	/// Create an encrypted connection out of the handshake. Consumes a handshake object.
 	pub fn new(mut handshake: Handshake) -> Result<EncryptedConnection, UtilError> {
 		let shared = try!(crypto::ecdh::agree(handshake.ecdhe.secret(), &handshake.remote_public));

util/src/network/error.rs

@@ -5,17 +5,17 @@ use rlp::*;
 pub enum DisconnectReason
 {
 	DisconnectRequested,
-	//TCPError,
-	//BadProtocol,
+	_TCPError,
+	_BadProtocol,
 	UselessPeer,
-	//TooManyPeers,
-	//DuplicatePeer,
-	//IncompatibleProtocol,
-	//NullIdentity,
-	//ClientQuit,
-	//UnexpectedIdentity,
-	//LocalIdentity,
-	//PingTimeout,
+	_TooManyPeers,
+	_DuplicatePeer,
+	_IncompatibleProtocol,
+	_NullIdentity,
+	_ClientQuit,
+	_UnexpectedIdentity,
+	_LocalIdentity,
+	PingTimeout,
 }
 
 #[derive(Debug)]

util/src/network/host.rs

@@ -19,6 +19,7 @@ use io::*;
 use network::NetworkProtocolHandler;
 use network::node::*;
 use network::stats::NetworkStats;
+use network::error::DisconnectReason;
 
 type Slab<T> = ::slab::Slab<T, usize>;
 
@@ -108,6 +109,8 @@ pub enum NetworkIoMessage<Message> where Message: Send + Sync + Clone {
 		/// Timer delay in milliseconds.
 		delay: u64,
 	},
+	/// Disconnect a peer
+	Disconnect(PeerId),
 	/// User message
 	User(Message),
 }
@@ -181,8 +184,14 @@ impl<'s, Message> NetworkContext<'s, Message> where Message: Send + Sync + Clone
 	}
 
 	/// Disable current protocol capability for given peer. If no capabilities left peer gets disconnected.
-	pub fn disable_peer(&self, _peer: PeerId) {
+	pub fn disable_peer(&self, peer: PeerId) {
 		//TODO: remove capability, disconnect if no capabilities left
+		self.disconnect_peer(peer);
+	}
+
+	/// Disconnect peer. Reconnect can be attempted later.
+	pub fn disconnect_peer(&self, peer: PeerId) {
+		self.io.message(NetworkIoMessage::Disconnect(peer));
 	}
 
 	/// Register a new IO timer. 'IoHandler::timeout' will be called with the token.
@@ -332,6 +341,7 @@ impl<Message> Host<Message> where Message: Send + Sync + Clone {
 	}
 
 	fn maintain_network(&self, io: &IoContext<NetworkIoMessage<Message>>) {
+		self.keep_alive(io);
 		self.connect_peers(io);
 	}
 
@@ -343,6 +353,21 @@ impl<Message> Host<Message> where Message: Send + Sync + Clone {
 		self.connections.read().unwrap().iter().any(|e| match *e.lock().unwrap().deref() { ConnectionEntry::Handshake(ref h) => h.id.eq(&id), _ => false  })
 	}
 
+	fn keep_alive(&self, io: &IoContext<NetworkIoMessage<Message>>) {
+		let mut to_kill = Vec::new();
+		for e in self.connections.write().unwrap().iter_mut() {
+			if let ConnectionEntry::Session(ref mut s) = *e.lock().unwrap().deref_mut() {
+				if !s.keep_alive() {
+					s.disconnect(DisconnectReason::PingTimeout);
+					to_kill.push(s.token());
+				}
+			}
+		}
+		for p in to_kill {
+			self.kill_connection(p, io);
+		}
+	}
+
 	fn connect_peers(&self, io: &IoContext<NetworkIoMessage<Message>>) {
 		struct NodeInfo {
 			id: NodeId,
@@ -684,6 +709,15 @@ impl<Message> IoHandler<NetworkIoMessage<Message>> for Host<Message> where Messa
 				self.timers.write().unwrap().insert(handler_token, ProtocolTimer { protocol: protocol, token: *token });
 				io.register_timer(handler_token, *delay).expect("Error registering timer");
 			},
+			NetworkIoMessage::Disconnect(ref peer) => {
+				if let Some(connection) = self.connections.read().unwrap().get(*peer).cloned() {
+					match *connection.lock().unwrap().deref_mut() {
+						ConnectionEntry::Handshake(_) => {},
+						ConnectionEntry::Session(ref mut s) => { s.disconnect(DisconnectReason::DisconnectRequested); } 
+					}
+				} 
+				self.kill_connection(*peer, io);
+			},
 			NetworkIoMessage::User(ref message) => {
 				for (p, h) in self.handlers.read().unwrap().iter() {
 					h.message(&NetworkContext::new(io, p, None, self.connections.clone()), &message);

util/src/network/service.rs

@@ -21,7 +21,7 @@ impl<Message> NetworkService<Message> where Message: Send + Sync + Clone + 'stat
 		let host = Arc::new(Host::new(config));
 		let stats = host.stats().clone();
 		let host_info = host.client_version();
-		info!("NetworkService::start(): id={:?}", host.client_id());
+		info!("Host ID={:?}", host.client_id());
 		try!(io_service.register_handler(host));
 		Ok(NetworkService {
 			io_service: io_service,

util/src/network/session.rs

@@ -4,10 +4,14 @@ use rlp::*;
 use network::connection::{EncryptedConnection, Packet};
 use network::handshake::Handshake;
 use error::*;
-use io::{IoContext};
+use io::{IoContext, StreamToken};
 use network::error::{NetworkError, DisconnectReason};
 use network::host::*;
 use network::node::NodeId;
+use time;
+
+const PING_TIMEOUT_SEC: u64 = 30;
+const PING_INTERVAL_SEC: u64 = 30;
 
 /// Peer session over encrypted connection.
 /// When created waits for Hello packet exchange and signals ready state.
@@ -19,6 +23,8 @@ pub struct Session {
 	connection: EncryptedConnection,
 	/// Session ready flag. Set after successfull Hello packet exchange
 	had_hello: bool,
+	ping_time_ns: u64,
+	pong_time_ns: Option<u64>,
 }
 
 /// Structure used to report various session events.
@@ -47,6 +53,8 @@ pub struct SessionInfo {
 	pub protocol_version: u32,
 	/// Peer protocol capabilities
 	capabilities: Vec<SessionCapabilityInfo>,
+	/// Peer ping delay in milliseconds
+	pub ping_ms: Option<u64>,
 }
 
 #[derive(Debug, PartialEq, Eq)]
@@ -95,10 +103,13 @@ impl Session {
 				client_version: String::new(),
 				protocol_version: 0,
 				capabilities: Vec::new(),
+				ping_ms: None,
 			},
+			ping_time_ns: 0,
+			pong_time_ns: None,
 		};
 		try!(session.write_hello(host));
-		try!(session.write_ping());
+		try!(session.send_ping());
 		Ok(session)
 	}
 
@@ -141,7 +152,7 @@ impl Session {
 		while protocol != self.info.capabilities[i].protocol {
 			i += 1;
 			if i == self.info.capabilities.len() {
-				debug!(target: "net", "Unkown protocol: {:?}", protocol);
+				debug!(target: "net", "Unknown protocol: {:?}", protocol);
 				return Ok(())
 			}
 		}
@@ -152,6 +163,26 @@ impl Session {
 		self.connection.send_packet(&rlp.out())
 	}
 
+	/// Keep this session alive. Returns false if ping timeout happened
+	pub fn keep_alive(&mut self) -> bool {
+		let timed_out = if let Some(pong) = self.pong_time_ns {
+			pong - self.ping_time_ns > PING_TIMEOUT_SEC * 1000_000_000
+		} else {
+			time::precise_time_ns() - self.ping_time_ns > PING_TIMEOUT_SEC * 1000_000_000
+		};
+
+		if !timed_out && time::precise_time_ns() - self.ping_time_ns > PING_INTERVAL_SEC * 1000_000_000 {
+			if let Err(e) = self.send_ping() {
+				debug!("Error sending ping message: {:?}", e);
+			}
+		}
+		!timed_out
+	}
+
+	pub fn token(&self) -> StreamToken {
+		self.connection.token()
+	}
+
 	fn read_packet(&mut self, packet: Packet, host: &HostInfo) -> Result<SessionData, UtilError> {
 		if packet.data.len() < 2 {
 			return Err(From::from(NetworkError::BadProtocol));
@@ -168,7 +199,12 @@ impl Session {
 			},
 			PACKET_DISCONNECT => Err(From::from(NetworkError::Disconnect(DisconnectReason::DisconnectRequested))),
 			PACKET_PING => {
-				try!(self.write_pong());
+				try!(self.send_pong());
+				Ok(SessionData::None)
+			},
+			PACKET_PONG => {
+				self.pong_time_ns = Some(time::precise_time_ns());
+				self.info.ping_ms = Some((self.pong_time_ns.unwrap() - self.ping_time_ns) / 1000_000);
 				Ok(SessionData::None)
 			},
 			PACKET_GET_PEERS => Ok(SessionData::None), //TODO;
@@ -178,7 +214,7 @@ impl Session {
 				while packet_id < self.info.capabilities[i].id_offset {
 					i += 1;
 					if i == self.info.capabilities.len() {
-						debug!(target: "net", "Unkown packet: {:?}", packet_id);
+						debug!(target: "net", "Unknown packet: {:?}", packet_id);
 						return Ok(SessionData::None)
 					}
 				}
@@ -189,7 +225,7 @@ impl Session {
 				Ok(SessionData::Packet { data: packet.data, protocol: protocol, packet_id: pid } )
 			},
 			_ => {
-				debug!(target: "net", "Unkown packet: {:?}", packet_id);
+				debug!(target: "net", "Unknown packet: {:?}", packet_id);
 				Ok(SessionData::None)
 			}
 		}
@@ -255,15 +291,20 @@ impl Session {
 		Ok(())
 	}
 
-	fn write_ping(&mut self) -> Result<(), UtilError>  {
-		self.send(try!(Session::prepare(PACKET_PING)))
+	/// Senf ping packet
+	pub fn send_ping(&mut self) -> Result<(), UtilError>  {
+		try!(self.send(try!(Session::prepare(PACKET_PING))));
+		self.ping_time_ns = time::precise_time_ns();
+		self.pong_time_ns = None;
+		Ok(())
 	}
 
-	fn write_pong(&mut self) -> Result<(), UtilError>  {
+	fn send_pong(&mut self) -> Result<(), UtilError>  {
 		self.send(try!(Session::prepare(PACKET_PONG)))
 	}
 
-	fn disconnect(&mut self, reason: DisconnectReason) -> NetworkError {
+	/// Disconnect this session
+	pub fn disconnect(&mut self, reason: DisconnectReason) -> NetworkError {
 		let mut rlp = RlpStream::new();
 		rlp.append(&(PACKET_DISCONNECT as u32));
 		rlp.begin_list(1);