Merge branch 'master' of github.com:ethcore/parity into docker

.gitmodules

@@ -1,4 +1,4 @@
 [submodule "ethcore/res/ethereum/tests"]
 	path = ethcore/res/ethereum/tests
-	url = git@github.com:ethereum/tests
+	url = https://github.com/ethereum/tests.git
-	branch = develop
+	branch = develop

.travis.yml

@@ -42,7 +42,7 @@ after_success: |
   ./kcov-master/tmp/usr/local/bin/kcov --exclude-pattern /.cargo,/root/.multirust target/kcov target/debug/deps/ethcore-* &&
   ./kcov-master/tmp/usr/local/bin/kcov --exclude-pattern /.cargo,/root/.multirust target/kcov target/debug/deps/ethsync-* &&
   ./kcov-master/tmp/usr/local/bin/kcov --exclude-pattern /.cargo,/root/.multirust target/kcov target/debug/deps/ethcore_rpc-* &&
-  ./kcov-master/tmp/usr/local/bin/kcov --coveralls-id=${COVERALLS_TOKEN} --exclude-pattern /.cargo,/root/.multirust target/kcov target/debug/parity-* &&
+  ./kcov-master/tmp/usr/local/bin/kcov --coveralls-id=${TRAVIS_JOB_ID} --exclude-pattern /.cargo,/root/.multirust target/kcov target/debug/parity-* &&
   [ $TRAVIS_BRANCH = master ] &&
   [ $TRAVIS_PULL_REQUEST = false ] &&
   [ $TRAVIS_RUST_VERSION = nightly ] &&

README.md

@@ -2,20 +2,22 @@
 
 [![Build Status][travis-image]][travis-url] [![Coverage Status][coveralls-image]][coveralls-url] [![Join the chat at https://gitter.im/trogdoro/xiki][gitter-image]][gitter-url]
 
-[travis-image]: https://travis-ci.com/ethcore/parity.svg?token=DMFvZu71iaTbUYx9UypX&branch=master
+[travis-image]: https://travis-ci.org/ethcore/parity.svg?branch=master
-[travis-url]: https://travis-ci.com/ethcore/parity
+[travis-url]: https://travis-ci.org/ethcore/parity
-[coveralls-image]: https://coveralls.io/repos/github/ethcore/parity/badge.svg?branch=master&t=Fk0OuQ
+[coveralls-image]: https://coveralls.io/repos/github/ethcore/parity/badge.svg?branch=master
-[coveralls-url]: https://coveralls.io/r/ethcore/parity?branch=master
+[coveralls-url]: https://coveralls.io/github/ethcore/parity?branch=master
 [gitter-image]: https://badges.gitter.im/Join%20Chat.svg
 [gitter-url]: https://gitter.im/ethcore/parity?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge
 
+[Documentation](http://ethcore.github.io/parity/ethcore/index.html)
+
 ### Building from source
 
-##### Ubuntu 14.04
+##### Ubuntu 14.04, 15.04, 15.10
 
 ```bash
 # install rocksdb
-add-apt-repository "deb http://ppa.launchpad.net/giskou/librocksdb/ubuntu trusty main"
+add-apt-repository ppa:ethcore/ethcore
 apt-get update
 apt-get install -y --force-yes librocksdb
 
@@ -32,7 +34,7 @@ cd parity
 cargo build --release
 ```
 
-##### Linux
+##### Other Linux
 
 ```bash
 # install rocksdb
@@ -72,3 +74,4 @@ git clone https://github.com/ethcore/parity
 cd parity
 cargo build --release
 ```
+

ethcore/res/ethereum/frontier.json

@@ -29,7 +29,8 @@
 	"nodes": [
 		"enode://a979fb575495b8d6db44f750317d0f4622bf4c2aa3365d6af7c284339968eef29b69ad0dce72a4d8db5ebb4968de0e3bec910127f134779fbcb0cb6d3331163c@52.16.188.185:30303",
 		"enode://de471bccee3d042261d52e9bff31458daecc406142b401d4cd848f677479f73104b9fdeb090af9583d3391b7f10cb2ba9e26865dd5fca4fcdc0fb1e3b723c786@54.94.239.50:30303",
-		"enode://1118980bf48b0a3640bdba04e0fe78b1add18e1cd99bf22d53daac1fd9972ad650df52176e7c7d89d1114cfef2bc23a2959aa54998a46afcf7d91809f0855082@52.74.57.123:30303"
+		"enode://1118980bf48b0a3640bdba04e0fe78b1add18e1cd99bf22d53daac1fd9972ad650df52176e7c7d89d1114cfef2bc23a2959aa54998a46afcf7d91809f0855082@52.74.57.123:30303",
+		"enode://859bbe6926fc161d218f62bd2efe0b4f6980205c00a5b928ccee39c94c440b73a054ece5db36beddd71963fbd296af61ec72a591f72a2299f9a046bd6d6ce1a9@parity-node-zero.ethcore.io:30303"
 	],
 	"accounts": {
 		"0000000000000000000000000000000000000001": { "builtin": { "name": "ecrecover", "linear": { "base": 3000, "word": 0 } } },

ethcore/src/block_queue.rs

@@ -30,8 +30,6 @@ use client::BlockStatus;
 /// Block queue status
 #[derive(Debug)]
 pub struct BlockQueueInfo {
-	/// Indicates that queue is full
-	pub full: bool,
 	/// Number of queued blocks pending verification
 	pub unverified_queue_size: usize,
 	/// Number of verified queued blocks pending import
@@ -46,6 +44,16 @@ impl BlockQueueInfo {
 
 	/// The size of the unverified and verifying queues.
 	pub fn incomplete_queue_size(&self) -> usize { self.unverified_queue_size + self.verifying_queue_size }
+
+	/// Indicates that queue is full
+	pub fn is_full(&self) -> bool {
+		self.unverified_queue_size + self.verified_queue_size + self.verifying_queue_size > MAX_UNVERIFIED_QUEUE_SIZE
+	}
+
+	/// Indicates that queue is empty
+	pub fn is_empty(&self) -> bool {
+		self.unverified_queue_size + self.verified_queue_size + self.verifying_queue_size == 0
+	}
 }
 
 /// A queue of blocks. Sits between network or other I/O and the BlockChain.
@@ -205,6 +213,8 @@ impl BlockQueue {
 		let mut verification = self.verification.lock().unwrap();
 		verification.unverified.clear();
 		verification.verifying.clear();
+		verification.verified.clear();
+		self.processing.write().unwrap().clear();
 	}
 
 	/// Wait for queue to be empty
@@ -285,7 +295,6 @@ impl BlockQueue {
 		for h in hashes {
 			processing.remove(&h);
 		}
-		//TODO: reward peers
 	}
 
 	/// Removes up to `max` verified blocks from the queue
@@ -308,7 +317,6 @@ impl BlockQueue {
 	pub fn queue_info(&self) -> BlockQueueInfo {
 		let verification = self.verification.lock().unwrap();
 		BlockQueueInfo {
-			full: verification.unverified.len() + verification.verifying.len() + verification.verified.len() >= MAX_UNVERIFIED_QUEUE_SIZE,
 			verified_queue_size: verification.verified.len(),
 			unverified_queue_size: verification.unverified.len(),
 			verifying_queue_size: verification.verifying.len(),
@@ -393,4 +401,14 @@ mod tests {
 			panic!("error importing block that has already been drained ({:?})", e);
 		}
 	}
+
+	#[test]
+	fn returns_empty_once_finished() {
+		let mut queue = get_test_queue();
+		queue.import_block(get_good_dummy_block()).expect("error importing block that is valid by definition");
+		queue.flush();
+		queue.drain(1);
+
+		assert!(queue.queue_info().is_empty());
+	}
 }

ethcore/src/client.rs

@@ -27,7 +27,7 @@ use spec::Spec;
 use engine::Engine;
 use views::HeaderView;
 use block_queue::{BlockQueue, BlockQueueInfo};
-use service::NetSyncMessage;
+use service::{NetSyncMessage, SyncMessage};
 use env_info::LastHashes;
 use verification::*;
 use block::*;
@@ -67,7 +67,6 @@ impl fmt::Display for BlockChainInfo {
 	}
 }
 
-
 /// Blockchain database client. Owns and manages a blockchain and a block queue.
 pub trait BlockChainClient : Sync + Send {
 	/// Get raw block header data by block header hash.
@@ -155,8 +154,7 @@ impl ClientReport {
 pub struct Client {
 	chain: Arc<RwLock<BlockChain>>,
 	engine: Arc<Box<Engine>>,
-	state_db: Arc<DB>,
+	state_db: Mutex<JournalDB>,
-	state_journal: Mutex<JournalDB>,
 	block_queue: RwLock<BlockQueue>,
 	report: RwLock<ClientReport>,
 	import_lock: Mutex<()>
@@ -209,8 +207,7 @@ impl Client {
 		Ok(Arc::new(Client {
 			chain: chain,
 			engine: engine.clone(),
-			state_db: db.clone(),
+			state_db: Mutex::new(state_db),
-			state_journal: Mutex::new(JournalDB::new_with_arc(db)),
 			block_queue: RwLock::new(BlockQueue::new(engine, message_channel)),
 			report: RwLock::new(Default::default()),
 			import_lock: Mutex::new(()),
@@ -223,7 +220,7 @@ impl Client {
 	}
 
 	/// This is triggered by a message coming from a block queue when the block is ready for insertion
-	pub fn import_verified_blocks(&self, _io: &IoChannel<NetSyncMessage>) -> usize {
+	pub fn import_verified_blocks(&self, io: &IoChannel<NetSyncMessage>) -> usize {
 		let mut ret = 0;
 		let mut bad = HashSet::new();
 		let _import_lock = self.import_lock.lock();
@@ -265,7 +262,7 @@ impl Client {
 				}
 			}
 
-			let db = self.state_journal.lock().unwrap().clone();
+			let db = self.state_db.lock().unwrap().clone();
 			let result = match enact_verified(&block, self.engine.deref().deref(), db, &parent, &last_hashes) {
 				Ok(b) => b,
 				Err(e) => {
@@ -295,6 +292,10 @@ impl Client {
 			self.report.write().unwrap().accrue_block(&block);
 			trace!(target: "client", "Imported #{} ({})", header.number(), header.hash());
 			ret += 1;
+
+			if self.block_queue.read().unwrap().queue_info().is_empty() {
+				io.send(NetworkIoMessage::User(SyncMessage::BlockVerified)).unwrap();
+			}
 		}
 		self.block_queue.write().unwrap().mark_as_good(&good_blocks);
 		ret
@@ -302,7 +303,7 @@ impl Client {
 
 	/// Get a copy of the best block's state.
 	pub fn state(&self) -> State {
-		State::from_existing(JournalDB::new_with_arc(self.state_db.clone()), HeaderView::new(&self.best_block_header()).state_root(), self.engine.account_start_nonce())
+		State::from_existing(self.state_db.lock().unwrap().clone(), HeaderView::new(&self.best_block_header()).state_root(), self.engine.account_start_nonce())
 	}
 
 	/// Get info on the cache.

install-deps.sh

@@ -570,7 +570,7 @@ function run_installer()
 		sudo apt-add-repository -y ppa:ethcore/ethcore
 		sudo apt-get -f -y install
 		sudo apt-get update -qq
-		sudo apt-get install -qq -y librocksdb
+		sudo apt-get install -qq -y librocksdb-dev
 	}
 
 	function linux_rocksdb_installer()
@@ -628,8 +628,8 @@ function run_installer()
 
 		if [[ $isMultirustNightly == false ]]; then
 			info "Installing rust nightly..."
-			sudo multirust update nightly
+			multirust update nightly
-			sudo multirust default nightly
+			multirust default nightly
 			echo
 		fi
 	}

parity/main.rs

@@ -33,6 +33,7 @@ extern crate fdlimit;
 #[cfg(feature = "rpc")]
 extern crate ethcore_rpc as rpc;
 
+use std::net::{SocketAddr};
 use std::env;
 use rlog::{LogLevelFilter};
 use env_logger::LogBuilder;
@@ -56,11 +57,15 @@ Options:
   -j --jsonrpc             Enable the JSON-RPC API sever.
   --jsonrpc-url URL        Specify URL for JSON-RPC API server [default: 127.0.0.1:8545].
 
+  --listen-address URL     Specify the IP/port on which to listen for peers [default: 0.0.0.0:30304].
+  --public-address URL     Specify the IP/port on which peers may connect [default: 0.0.0.0:30304].
+  --address URL            Equivalent to --listen-address URL --public-address URL.
+
   --cache-pref-size BYTES  Specify the prefered size of the blockchain cache in bytes [default: 16384].
   --cache-max-size BYTES   Specify the maximum size of the blockchain cache in bytes [default: 262144].
 
   -h --help                Show this screen.
-", flag_cache_pref_size: usize, flag_cache_max_size: usize);
+", flag_cache_pref_size: usize, flag_cache_max_size: usize, flag_address: Option<String>);
 
 fn setup_log(init: &str) {
 	let mut builder = LogBuilder::new();
@@ -105,6 +110,16 @@ fn main() {
 	};
 	let mut net_settings = NetworkConfiguration::new();
 	net_settings.boot_nodes = init_nodes;
+	match args.flag_address {
+		None => {
+			net_settings.listen_address = SocketAddr::from_str(args.flag_listen_address.as_ref()).expect("Invalid listen address given with --listen-address");
+			net_settings.public_address = SocketAddr::from_str(args.flag_public_address.as_ref()).expect("Invalid public address given with --public-address");
+		}
+		Some(ref a) => {
+			net_settings.public_address = SocketAddr::from_str(a.as_ref()).expect("Invalid listen/public address given with --address");
+			net_settings.listen_address = net_settings.public_address.clone();
+		}
+	}
 	let mut service = ClientService::start(spec, net_settings).unwrap();
 	let client = service.client().clone();
 	client.configure_cache(args.flag_cache_pref_size, args.flag_cache_max_size);

sync/Cargo.toml

@@ -14,4 +14,4 @@ clippy = "0.0.37"
 log = "0.3"
 env_logger = "0.3"
 time = "0.1.34"
-
+rand = "0.3.13"

sync/src/chain.rs

@@ -62,6 +62,9 @@ const MAX_NODE_DATA_TO_SEND: usize = 1024;
 const MAX_RECEIPTS_TO_SEND: usize = 1024;
 const MAX_HEADERS_TO_REQUEST: usize = 512;
 const MAX_BODIES_TO_REQUEST: usize = 256;
+const MIN_PEERS_PROPAGATION: usize = 4;
+const MAX_PEERS_PROPAGATION: usize = 128;
+const MAX_PEER_LAG_PROPAGATION: BlockNumber = 20;
 
 const STATUS_PACKET: u8 = 0x00;
 const NEW_BLOCK_HASHES_PACKET: u8 = 0x01;
@@ -134,7 +137,7 @@ pub struct SyncStatus {
 	pub num_active_peers: usize,
 }
 
-#[derive(PartialEq, Eq, Debug)]
+#[derive(PartialEq, Eq, Debug, Clone)]
 /// Peer data type requested
 enum PeerAsking {
 	Nothing,
@@ -142,6 +145,7 @@ enum PeerAsking {
 	BlockBodies,
 }
 
+#[derive(Clone)]
 /// Syncing peer information
 struct PeerInfo {
 	/// eth protocol version
@@ -430,12 +434,11 @@ impl ChainSync {
 		let block_rlp = try!(r.at(0));
 		let header_rlp = try!(block_rlp.at(0));
 		let h = header_rlp.as_raw().sha3();
-
 		trace!(target: "sync", "{} -> NewBlock ({})", peer_id, h);
-		let header_view = HeaderView::new(header_rlp.as_raw());
+		let header: BlockHeader = try!(header_rlp.as_val());
  		let mut unknown = false;
 		// TODO: Decompose block and add to self.headers and self.bodies instead
-		if header_view.number() == From::from(self.current_base_block() + 1) {
+		if header.number == From::from(self.current_base_block() + 1) {
 			match io.chain().import_block(block_rlp.as_raw().to_vec()) {
 				Err(ImportError::AlreadyInChain) => {
 					trace!(target: "sync", "New block already in chain {:?}", h);
@@ -468,7 +471,7 @@ impl ChainSync {
 				trace!(target: "sync", "Received block {:?}  with no known parent. Peer needs syncing...", h);
 				{
 					let peer = self.peers.get_mut(&peer_id).expect("ChainSync: unknown peer");
-					peer.latest = header_view.sha3();
+					peer.latest = header.hash();
 				}
 				self.sync_peer(io, peer_id, true);
 			}
@@ -593,7 +596,7 @@ impl ChainSync {
 	fn request_blocks(&mut self, io: &mut SyncIo, peer_id: PeerId) {
 		self.clear_peer_download(peer_id);
 
-		if io.chain().queue_info().full {
+		if io.chain().queue_info().is_full() {
 			self.pause_sync();
 			return;
 		}
@@ -636,6 +639,7 @@ impl ChainSync {
 				if start == 0 {
 					self.have_common_block = true; //reached genesis
 					self.last_imported_hash = Some(chain_info.genesis_hash);
+					self.last_imported_block = Some(0);
 				}
 			}
 			if self.have_common_block {
@@ -1030,10 +1034,6 @@ impl ChainSync {
 		})
 	}
 
-	/// Maintain other peers. Send out any new blocks and transactions
-	pub fn _maintain_sync(&mut self, _io: &mut SyncIo) {
-	}
-
 	pub fn maintain_peers(&self, io: &mut SyncIo) {
 		let tick = time::precise_time_s();
 		for (peer_id, peer) in &self.peers {
@@ -1042,13 +1042,125 @@ impl ChainSync {
 			}
 		}
 	}
-	/// Maintain other peers. Send out any new blocks and transactions
+
-	pub fn maintain_sync(&mut self, io: &mut SyncIo) {
+	fn check_resume(&mut self, io: &mut SyncIo) {
-		if !io.chain().queue_info().full && self.state == SyncState::Waiting {
+		if !io.chain().queue_info().is_full() && self.state == SyncState::Waiting {
 			self.state = SyncState::Idle;
 			self.continue_sync(io);
 		}
 	}
+
+	/// creates rlp to send for the tree defined by 'from' and 'to' hashes
+	fn create_new_hashes_rlp(chain: &BlockChainClient, from: &H256, to: &H256) -> Option<Bytes> {
+		match chain.tree_route(from, to) {
+			Some(route) => {
+				match route.blocks.len() {
+					0 => None,
+					_ => {
+						let mut rlp_stream = RlpStream::new_list(route.blocks.len());
+						for block_hash in route.blocks {
+							let mut hash_rlp = RlpStream::new_list(2);
+							let difficulty = chain.block_total_difficulty(&block_hash).expect("Mallformed block without a difficulty on the chain!");
+							hash_rlp.append(&block_hash);
+							hash_rlp.append(&difficulty);
+							rlp_stream.append_raw(&hash_rlp.out(), 1);
+						}
+						Some(rlp_stream.out())
+					}
+				}
+			},
+			None => None
+		}
+	}
+
+	/// creates latest block rlp for the given client
+	fn create_latest_block_rlp(chain: &BlockChainClient) -> Bytes {
+		let mut rlp_stream = RlpStream::new_list(2);
+		rlp_stream.append_raw(&chain.block(&chain.chain_info().best_block_hash).expect("Creating latest block when there is none"), 1);
+		rlp_stream.append(&chain.chain_info().total_difficulty);
+		rlp_stream.out()
+	}
+
+	/// returns peer ids that have less blocks than our chain
+	fn get_lagging_peers(&self, io: &SyncIo) -> Vec<PeerId> {
+		let chain = io.chain();
+		let chain_info = chain.chain_info();
+		let latest_hash = chain_info.best_block_hash;
+		let latest_number = chain_info.best_block_number;
+		self.peers.iter().filter(|&(_, peer_info)|
+			match io.chain().block_status(&peer_info.latest)
+			{
+				BlockStatus::InChain => {
+					let peer_number = HeaderView::new(&io.chain().block_header(&peer_info.latest).unwrap()).number();
+					peer_info.latest != latest_hash && latest_number > peer_number && latest_number - peer_number < MAX_PEER_LAG_PROPAGATION
+				},
+				_ => false
+			})
+			.map(|(peer_id, _)| peer_id)
+			.cloned().collect::<Vec<PeerId>>()
+	}
+
+	/// propagades latest block to lagging peers
+	fn propagade_blocks(&mut self, io: &mut SyncIo) -> usize {
+		let updated_peers = {
+			let lagging_peers = self.get_lagging_peers(io);
+
+			// sqrt(x)/x scaled to max u32
+			let fraction = (self.peers.len() as f64).powf(-0.5).mul(u32::max_value() as f64).round() as u32;
+			let lucky_peers = match lagging_peers.len() {
+				0 ... MIN_PEERS_PROPAGATION => lagging_peers,
+				_ => lagging_peers.iter().filter(|_| ::rand::random::<u32>() < fraction).cloned().collect::<Vec<PeerId>>()
+			};
+
+			// taking at max of MAX_PEERS_PROPAGATION
+			lucky_peers.iter().take(min(lucky_peers.len(), MAX_PEERS_PROPAGATION)).cloned().collect::<Vec<PeerId>>()
+		};
+
+		let mut sent = 0;
+		let local_best = io.chain().chain_info().best_block_hash;
+		for peer_id in updated_peers {
+			let rlp = ChainSync::create_latest_block_rlp(io.chain());
+			self.send_request(io, peer_id, PeerAsking::Nothing, NEW_BLOCK_PACKET, rlp);
+			self.peers.get_mut(&peer_id).expect("ChainSync: unknown peer").latest = local_best.clone();
+			sent = sent + 1;
+		}
+		sent
+	}
+
+	/// propagades new known hashes to all peers
+	fn propagade_new_hashes(&mut self, io: &mut SyncIo) -> usize {
+		let updated_peers = self.get_lagging_peers(io);
+		let mut sent = 0;
+		let local_best = io.chain().chain_info().best_block_hash;
+		for peer_id in updated_peers {
+			sent = sent + match ChainSync::create_new_hashes_rlp(io.chain(), &self.peers.get(&peer_id).expect("ChainSync: unknown peer").latest, &local_best) {
+				Some(rlp) => {
+					{
+						let peer = self.peers.get_mut(&peer_id).expect("ChainSync: unknown peer");
+						peer.latest = local_best.clone();
+					}
+					self.send_request(io, peer_id, PeerAsking::Nothing, NEW_BLOCK_HASHES_PACKET, rlp);
+					1
+				},
+				None => 0
+			}
+		}
+		sent
+	}
+
+	/// Maintain other peers. Send out any new blocks and transactions
+	pub fn maintain_sync(&mut self, io: &mut SyncIo) {
+		self.check_resume(io);
+
+		let peers = self.propagade_new_hashes(io);
+		trace!(target: "sync", "Sent new hashes to peers: {:?}", peers);
+	}
+
+	/// should be called once chain has new block, triggers the latest block propagation
+	pub fn chain_blocks_verified(&mut self, io: &mut SyncIo) {
+		let peers = self.propagade_blocks(io);
+		trace!(target: "sync", "Sent latest block to peers: {:?}", peers);
+	}
 }
 
 #[cfg(test)]
@@ -1056,6 +1168,48 @@ mod tests {
 	use tests::helpers::*;
 	use super::*;
 	use util::*;
+	use super::{PeerInfo, PeerAsking};
+	use ethcore::header::*;
+	use ethcore::client::*;
+
+	fn get_dummy_block(order: u32, parent_hash: H256) -> Bytes {
+		let mut header = Header::new();
+		header.gas_limit = x!(0);
+		header.difficulty = x!(order * 100);
+		header.timestamp = (order * 10) as u64;
+		header.number = order as u64;
+		header.parent_hash = parent_hash;
+		header.state_root = H256::zero();
+
+		let mut rlp = RlpStream::new_list(3);
+		rlp.append(&header);
+		rlp.append_raw(&rlp::EMPTY_LIST_RLP, 1);
+		rlp.append_raw(&rlp::EMPTY_LIST_RLP, 1);
+		rlp.out()
+	}
+
+	fn get_dummy_blocks(order: u32, parent_hash: H256) -> Bytes {
+		let mut rlp = RlpStream::new_list(1);
+		rlp.append_raw(&get_dummy_block(order, parent_hash), 1);
+		let difficulty: U256 = x!(100 * order);
+		rlp.append(&difficulty);
+		rlp.out()
+	}
+
+	fn get_dummy_hashes() -> Bytes {
+		let mut rlp = RlpStream::new_list(5);
+		for _ in 0..5 {
+			let mut hash_d_rlp = RlpStream::new_list(2);
+			let hash: H256 = H256::from(0u64);
+			let diff: U256 = U256::from(1u64);
+			hash_d_rlp.append(&hash);
+			hash_d_rlp.append(&diff);
+
+			rlp.append_raw(&hash_d_rlp.out(), 1);
+		}
+
+		rlp.out()
+	}
 
 	#[test]
 	fn return_receipts_empty() {
@@ -1124,4 +1278,204 @@ mod tests {
 		sync.on_packet(&mut io, 1usize, super::GET_NODE_DATA_PACKET, &node_request);
 		assert_eq!(1, io.queue.len());
 	}
+
+	fn dummy_sync_with_peer(peer_latest_hash: H256) -> ChainSync {
+		let mut sync = ChainSync::new();
+		sync.peers.insert(0,
+		  	PeerInfo {
+				protocol_version: 0,
+				genesis: H256::zero(),
+				network_id: U256::zero(),
+				latest: peer_latest_hash,
+				difficulty: U256::zero(),
+				asking: PeerAsking::Nothing,
+				asking_blocks: Vec::<BlockNumber>::new(),
+				ask_time: 0f64,
+	  		});
+		sync
+	}
+
+	#[test]
+	fn finds_lagging_peers() {
+		let mut client = TestBlockChainClient::new();
+		client.add_blocks(100, false);
+		let mut queue = VecDeque::new();
+		let sync = dummy_sync_with_peer(client.block_hash_delta_minus(10));
+		let io = TestIo::new(&mut client, &mut queue, None);
+
+		let lagging_peers = sync.get_lagging_peers(&io);
+
+		assert_eq!(1, lagging_peers.len())
+	}
+
+	#[test]
+	fn calculates_tree_for_lagging_peer() {
+		let mut client = TestBlockChainClient::new();
+		client.add_blocks(15, false);
+
+		let start = client.block_hash_delta_minus(4);
+		let end = client.block_hash_delta_minus(2);
+
+		// wrong way end -> start, should be None
+		let rlp = ChainSync::create_new_hashes_rlp(&client, &end, &start);
+		assert!(rlp.is_none());
+
+		let rlp = ChainSync::create_new_hashes_rlp(&client, &start, &end).unwrap();
+		// size of three rlp encoded hash-difficulty
+		assert_eq!(107, rlp.len());
+	}
+
+	#[test]
+	fn sends_new_hashes_to_lagging_peer() {
+		let mut client = TestBlockChainClient::new();
+		client.add_blocks(100, false);
+		let mut queue = VecDeque::new();
+		let mut sync = dummy_sync_with_peer(client.block_hash_delta_minus(5));
+		let mut io = TestIo::new(&mut client, &mut queue, None);
+
+		let peer_count = sync.propagade_new_hashes(&mut io);
+
+		// 1 message should be send
+		assert_eq!(1, io.queue.len());
+		// 1 peer should be updated
+		assert_eq!(1, peer_count);
+		// NEW_BLOCK_HASHES_PACKET
+		assert_eq!(0x01, io.queue[0].packet_id);
+	}
+
+	#[test]
+	fn sends_latest_block_to_lagging_peer() {
+		let mut client = TestBlockChainClient::new();
+		client.add_blocks(100, false);
+		let mut queue = VecDeque::new();
+		let mut sync = dummy_sync_with_peer(client.block_hash_delta_minus(5));
+		let mut io = TestIo::new(&mut client, &mut queue, None);
+
+		let peer_count = sync.propagade_blocks(&mut io);
+
+		// 1 message should be send
+		assert_eq!(1, io.queue.len());
+		// 1 peer should be updated
+		assert_eq!(1, peer_count);
+		// NEW_BLOCK_PACKET
+		assert_eq!(0x07, io.queue[0].packet_id);
+	}
+
+	#[test]
+	fn handles_peer_new_block_mallformed() {
+		let mut client = TestBlockChainClient::new();
+		client.add_blocks(10, false);
+
+		let block_data = get_dummy_block(11, client.chain_info().best_block_hash);
+
+		let mut queue = VecDeque::new();
+		let mut sync = dummy_sync_with_peer(client.block_hash_delta_minus(5));
+		let mut io = TestIo::new(&mut client, &mut queue, None);
+
+		let block = UntrustedRlp::new(&block_data);
+
+		let result = sync.on_peer_new_block(&mut io, 0, &block);
+
+		assert!(result.is_err());
+	}
+
+	#[test]
+	fn handles_peer_new_block() {
+		let mut client = TestBlockChainClient::new();
+		client.add_blocks(10, false);
+
+		let block_data = get_dummy_blocks(11, client.chain_info().best_block_hash);
+
+		let mut queue = VecDeque::new();
+		let mut sync = dummy_sync_with_peer(client.block_hash_delta_minus(5));
+		let mut io = TestIo::new(&mut client, &mut queue, None);
+
+		let block = UntrustedRlp::new(&block_data);
+
+		let result = sync.on_peer_new_block(&mut io, 0, &block);
+
+		assert!(result.is_ok());
+	}
+
+	#[test]
+	fn handles_peer_new_block_empty() {
+		let mut client = TestBlockChainClient::new();
+		client.add_blocks(10, false);
+		let mut queue = VecDeque::new();
+		let mut sync = dummy_sync_with_peer(client.block_hash_delta_minus(5));
+		let mut io = TestIo::new(&mut client, &mut queue, None);
+
+		let empty_data = vec![];
+		let block = UntrustedRlp::new(&empty_data);
+
+		let result = sync.on_peer_new_block(&mut io, 0, &block);
+
+		assert!(result.is_err());
+	}
+
+	#[test]
+	fn handles_peer_new_hashes() {
+		let mut client = TestBlockChainClient::new();
+		client.add_blocks(10, false);
+		let mut queue = VecDeque::new();
+		let mut sync = dummy_sync_with_peer(client.block_hash_delta_minus(5));
+		let mut io = TestIo::new(&mut client, &mut queue, None);
+
+		let hashes_data = get_dummy_hashes();
+		let hashes_rlp = UntrustedRlp::new(&hashes_data);
+
+		let result = sync.on_peer_new_hashes(&mut io, 0, &hashes_rlp);
+
+		assert!(result.is_ok());
+	}
+
+	#[test]
+	fn handles_peer_new_hashes_empty() {
+		let mut client = TestBlockChainClient::new();
+		client.add_blocks(10, false);
+		let mut queue = VecDeque::new();
+		let mut sync = dummy_sync_with_peer(client.block_hash_delta_minus(5));
+		let mut io = TestIo::new(&mut client, &mut queue, None);
+
+		let empty_hashes_data = vec![];
+		let hashes_rlp = UntrustedRlp::new(&empty_hashes_data);
+
+		let result = sync.on_peer_new_hashes(&mut io, 0, &hashes_rlp);
+
+		assert!(result.is_ok());
+	}
+
+	// idea is that what we produce when propagading latest hashes should be accepted in
+	// on_peer_new_hashes in our code as well
+	#[test]
+	fn hashes_rlp_mutually_acceptable() {
+		let mut client = TestBlockChainClient::new();
+		client.add_blocks(100, false);
+		let mut queue = VecDeque::new();
+		let mut sync = dummy_sync_with_peer(client.block_hash_delta_minus(5));
+		let mut io = TestIo::new(&mut client, &mut queue, None);
+
+		sync.propagade_new_hashes(&mut io);
+
+		let data = &io.queue[0].data.clone();
+		let result = sync.on_peer_new_hashes(&mut io, 0, &UntrustedRlp::new(&data));
+		assert!(result.is_ok());
+	}
+
+	// idea is that what we produce when propagading latest block should be accepted in
+	// on_peer_new_block  in our code as well
+	#[test]
+	fn block_rlp_mutually_acceptable() {
+		let mut client = TestBlockChainClient::new();
+		client.add_blocks(100, false);
+		let mut queue = VecDeque::new();
+		let mut sync = dummy_sync_with_peer(client.block_hash_delta_minus(5));
+		let mut io = TestIo::new(&mut client, &mut queue, None);
+
+		sync.propagade_blocks(&mut io);
+
+		let data = &io.queue[0].data.clone();
+		let result = sync.on_peer_new_block(&mut io, 0, &UntrustedRlp::new(&data));
+		assert!(result.is_ok());
+	}
 }

sync/src/lib.rs

@@ -50,6 +50,7 @@ extern crate ethcore_util as util;
 extern crate ethcore;
 extern crate env_logger;
 extern crate time;
+extern crate rand;
 
 use std::ops::*;
 use std::sync::*;
@@ -125,4 +126,10 @@ impl NetworkProtocolHandler<SyncMessage> for EthSync {
 		self.sync.write().unwrap().maintain_peers(&mut NetSyncIo::new(io, self.chain.deref()));
 		self.sync.write().unwrap().maintain_sync(&mut NetSyncIo::new(io, self.chain.deref()));
 	}
+
+	fn message(&self, io: &NetworkContext<SyncMessage>, message: &SyncMessage) {
+		if let SyncMessage::BlockVerified = *message {
+			self.sync.write().unwrap().chain_blocks_verified(&mut NetSyncIo::new(io, self.chain.deref()));
+		}
+	}
 }

sync/src/tests/chain.rs

@@ -104,4 +104,48 @@ fn restart() {
 fn status_empty() {
 	let net = TestNet::new(2);
 	assert_eq!(net.peer(0).sync.status().state, SyncState::NotSynced);
+}
+
+#[test]
+fn status_packet() {
+	let mut net = TestNet::new(2);
+	net.peer_mut(0).chain.add_blocks(1000, false);
+	net.peer_mut(1).chain.add_blocks(1, false);
+
+	net.start();
+
+	net.sync_step_peer(0);
+
+	assert_eq!(1, net.peer(0).queue.len());
+	assert_eq!(0x00, net.peer(0).queue[0].packet_id);
+}
+
+#[test]
+fn propagade_hashes() {
+	let mut net = TestNet::new(3);
+	net.peer_mut(1).chain.add_blocks(1000, false);
+	net.peer_mut(2).chain.add_blocks(1000, false);
+	net.sync();
+
+	net.peer_mut(0).chain.add_blocks(10, false);
+	net.sync_step_peer(0);
+
+	// 2 peers to sync
+	assert_eq!(2, net.peer(0).queue.len());
+	// NEW_BLOCK_HASHES_PACKET
+	assert_eq!(0x01, net.peer(0).queue[0].packet_id);
+}
+
+#[test]
+fn propagade_blocks() {
+	let mut net = TestNet::new(2);
+	net.peer_mut(1).chain.add_blocks(10, false);
+	net.sync();
+
+	net.peer_mut(0).chain.add_blocks(10, false);
+	net.trigger_block_verified(0);
+
+	assert!(!net.peer(0).queue.is_empty());
+	// NEW_BLOCK_PACKET
+	assert_eq!(0x07, net.peer(0).queue[0].packet_id);
 }

sync/src/tests/helpers.rs

@@ -69,16 +69,21 @@ impl TestBlockChainClient {
 			self.import_block(rlp.as_raw().to_vec()).unwrap();
 		}
 	}
+
+	pub fn block_hash_delta_minus(&mut self, delta: usize) -> H256 {
+		let blocks_read = self.numbers.read().unwrap();
+		let index = blocks_read.len() - delta;
+		blocks_read[&index].clone()
+	}
 }
 
 impl BlockChainClient for TestBlockChainClient {
 	fn block_total_difficulty(&self, _h: &H256) -> Option<U256> {
-		unimplemented!();
+		Some(U256::zero())
 	}
 
 	fn block_header(&self, h: &H256) -> Option<Bytes> {
 		self.blocks.read().unwrap().get(h).map(|r| Rlp::new(r).at(0).as_raw().to_vec())
-
 	}
 
 	fn block_body(&self, h: &H256) -> Option<Bytes> {
@@ -125,11 +130,33 @@ impl BlockChainClient for TestBlockChainClient {
 		}
 	}
 
-	fn tree_route(&self, _from: &H256, _to: &H256) -> Option<TreeRoute> {
+	// works only if blocks are one after another 1 -> 2 -> 3
+	fn tree_route(&self, from: &H256, to: &H256) -> Option<TreeRoute> {
 		Some(TreeRoute {
-			blocks: Vec::new(),
 			ancestor: H256::new(),
-			index: 0
+			index: 0,
+			blocks: {
+				let numbers_read = self.numbers.read().unwrap();
+				let mut adding = false;
+
+				let mut blocks = Vec::new();
+				for (_, hash) in numbers_read.iter().sort_by(|tuple1, tuple2| tuple1.0.cmp(tuple2.0)) {
+					if hash == to {
+						if adding {
+							blocks.push(hash.clone());
+						}
+						adding = false;
+						break;
+					}
+					if hash == from {
+						adding = true;
+					}
+					if adding {
+						blocks.push(hash.clone());
+					}
+				}
+				if adding { Vec::new() } else { blocks }
+			}
 		})
 	}
 
@@ -202,7 +229,6 @@ impl BlockChainClient for TestBlockChainClient {
 
 	fn queue_info(&self) -> BlockQueueInfo {
 		BlockQueueInfo {
-			full: false,
 			verified_queue_size: 0,
 			unverified_queue_size: 0,
 			verifying_queue_size: 0,
@@ -334,6 +360,11 @@ impl TestNet {
 		}
 	}
 
+	pub fn sync_step_peer(&mut self, peer_num: usize) {
+		let mut peer = self.peer_mut(peer_num);
+		peer.sync.maintain_sync(&mut TestIo::new(&mut peer.chain, &mut peer.queue, None));
+	}
+
 	pub fn restart_peer(&mut self, i: usize) {
 		let peer = self.peer_mut(i);
 		peer.sync.restart(&mut TestIo::new(&mut peer.chain, &mut peer.queue, None));
@@ -362,4 +393,9 @@ impl TestNet {
 	pub fn done(&self) -> bool {
 		self.peers.iter().all(|p| p.queue.is_empty())
 	}
+
+	pub fn trigger_block_verified(&mut self, peer_id: usize) {
+		let mut peer = self.peer_mut(peer_id);
+		peer.sync.chain_blocks_verified(&mut TestIo::new(&mut peer.chain, &mut peer.queue, None));
+	}
 }

util/src/journaldb.rs

@@ -92,7 +92,6 @@ impl JournalDB {
 
 	/// Commit all recent insert operations and historical removals from the old era
 	/// to the backing database.
-	#[allow(cyclomatic_complexity)]
 	pub fn commit(&mut self, now: u64, id: &H256, end: Option<(u64, H256)>) -> Result<u32, UtilError> {
 		// journal format: 
 		// [era, 0] => [ id, [insert_0, ...], [remove_0, ...] ]
@@ -105,6 +104,17 @@ impl JournalDB {
 		// for each end_era that we journaled that we are no passing by, 
 		// we remove all of its removes assuming it is canonical and all
 		// of its inserts otherwise.
+		//
+		// We also keep reference counters for each key inserted in the journal to handle 
+		// the following cases where key K must not be deleted from the DB when processing removals :
+		// Given H is the journal size in eras, 0 <= C <= H.
+		// Key K is removed in era A(N) and re-inserted in canonical era B(N + C).
+		// Key K is removed in era A(N) and re-inserted in non-canonical era B`(N + C).
+		// Key K is added in non-canonical era A'(N) canonical B(N + C).
+		//
+		// The counter is encreased each time a key is inserted in the journal in the commit. The list of insertions
+		// is saved with the era record. When the era becomes end_era and goes out of journal the counter is decreased
+		// and the key is safe to delete.
 
 		// record new commit's details.
 		let batch = WriteBatch::new();
@@ -125,6 +135,7 @@ impl JournalDB {
 
 			let mut r = RlpStream::new_list(3);
 			let inserts: Vec<H256> = self.overlay.keys().iter().filter(|&(_, &c)| c > 0).map(|(key, _)| key.clone()).collect();
+			// Increase counter for each inserted key no matter if the block is canonical or not. 
 			for i in &inserts {
 				*counters.entry(i.clone()).or_insert(0) += 1;
 			}
@@ -139,6 +150,8 @@ impl JournalDB {
 		if let Some((end_era, canon_id)) = end {
 			let mut index = 0usize;
 			let mut last;
+			let mut to_remove: Vec<H256> = Vec::new();
+			let mut canon_inserts: Vec<H256> = Vec::new();
 			while let Some(rlp_data) = try!(self.backing.get({
 				let mut r = RlpStream::new_list(2);
 				r.append(&end_era);
@@ -146,39 +159,33 @@ impl JournalDB {
 				last = r.drain();
 				&last
 			})) {
-				let to_add;
 				let rlp = Rlp::new(&rlp_data);
-				{
+				let inserts: Vec<H256> = rlp.val_at(1);
-					to_add = rlp.val_at(1);
+				JournalDB::decrease_counters(&inserts, &mut counters);
-					for i in &to_add {
+				// Collect keys to be removed. These are removed keys for canonical block, inserted for non-canonical
-						let delete_counter = {
+				if canon_id == rlp.val_at(0) {
-							if let Some(mut cnt) = counters.get_mut(i) {
+					to_remove.extend(rlp.at(2).iter().map(|r| r.as_val::<H256>()));
-								*cnt -= 1;
+					canon_inserts = inserts;
-								*cnt == 0 
-							}
-							else { false }
-								 
-						};
-						if delete_counter { 
-							counters.remove(i); 
-						}
-					}
 				}
-				let to_remove: Vec<H256> = if canon_id == rlp.val_at(0) {rlp.val_at(2)} else {to_add};
+				else {
-				for i in &to_remove {
+					to_remove.extend(inserts);
-					if !counters.contains_key(i) {
-						batch.delete(&i).expect("Low-level database error. Some issue with your hard disk?");
-					}
 				}
-
 				try!(batch.delete(&last));
-				trace!("JournalDB: delete journal for time #{}.{}, (canon was {}): {} entries", end_era, index, canon_id, to_remove.len());
 				index += 1;
 			}
 
+			let canon_inserts = canon_inserts.drain(..).collect::<HashSet<_>>();
+			// Purge removed keys if they are not referenced and not re-inserted in the canon commit
+			let mut deletes = 0;
+			for h in to_remove.iter().filter(|h| !counters.contains_key(h) && !canon_inserts.contains(h)) {
+				try!(batch.delete(&h));
+				deletes += 1;
+			}
 			try!(batch.put(&LAST_ERA_KEY, &encode(&end_era)));
+			trace!("JournalDB: delete journal for time #{}.{}, (canon was {}): {} entries", end_era, index, canon_id, deletes);
 		}
 
+		// Commit overlay insertions
 		let mut ret = 0u32;
 		let mut deletes = 0usize;
 		for i in self.overlay.drain().into_iter() {
@@ -200,6 +207,21 @@ impl JournalDB {
 		Ok(ret)
 	}
 
+
+	// Decrease counters for given keys. Deletes obsolete counters
+	fn decrease_counters(keys: &[H256], counters: &mut HashMap<H256, i32>) {
+		for i in keys.iter() {
+			let delete_counter = {
+				let cnt = counters.get_mut(i).expect("Missing key counter");
+				*cnt -= 1;
+				*cnt == 0
+			};
+			if delete_counter {
+				counters.remove(i);
+			}
+		}
+	}
+
 	fn payload(&self, key: &H256) -> Option<Bytes> {
 		self.backing.get(&key.bytes()).expect("Low-level database error. Some issue with your hard disk?").map(|v| v.to_vec())
 	}
@@ -387,4 +409,21 @@ mod tests {
 		jdb.commit(3, &b"2".sha3(), Some((0, b"2".sha3()))).unwrap();
 		assert!(jdb.exists(&foo));
 	}
+
+	#[test]
+	fn fork_same_key() {
+		// history is 1
+		let mut jdb = JournalDB::new_temp();
+		jdb.commit(0, &b"0".sha3(), None).unwrap();
+
+		let foo = jdb.insert(b"foo");
+		jdb.commit(1, &b"1a".sha3(), Some((0, b"0".sha3()))).unwrap();
+
+		jdb.insert(b"foo");
+		jdb.commit(1, &b"1b".sha3(), Some((0, b"0".sha3()))).unwrap();
+		assert!(jdb.exists(&foo));
+
+		jdb.commit(2, &b"2a".sha3(), Some((1, b"1a".sha3()))).unwrap();
+		assert!(jdb.exists(&foo));
+	}
 }

util/src/network/host.rs

@@ -599,6 +599,9 @@ impl<Message> Host<Message> where Message: Send + Sync + Clone {
 
 	fn start_session(&self, token: StreamToken, io: &IoContext<NetworkIoMessage<Message>>) {
 		let mut connections = self.connections.write().unwrap();
+		if connections.get(token).is_none() {
+			return; // handshake expired
+		}
 		connections.replace_with(token, |c| {
 			match Arc::try_unwrap(c).ok().unwrap().into_inner().unwrap() {
 				ConnectionEntry::Handshake(h) => {