Update to new gossip system. (#172)

* Integrates new gossip system into Polkadot (#166)

* new gossip validation in network

* integrate new gossip into service

* Fix build

* Fix claims module

* fix warning

* update to latest master again

* update runtime

polkadot/network/src/validation.rs

@@ -20,7 +20,7 @@
 //! each time a validation session begins on a new chain head.
 
 use sr_primitives::traits::ProvideRuntimeApi;
-use substrate_network::{consensus_gossip::ConsensusMessage, Context as NetContext};
+use substrate_network::Context as NetContext;
 use polkadot_validation::{Network as ParachainNetwork, SharedTable, Collators, Statement, GenericStatement};
 use polkadot_primitives::{AccountId, Block, Hash, SessionKey};
 use polkadot_primitives::parachain::{Id as ParaId, Collation, Extrinsic, ParachainHost, BlockData};
@@ -38,6 +38,8 @@ use tokio::runtime::TaskExecutor;
 use parking_lot::Mutex;
 
 use router::Router;
+use gossip::{POLKADOT_ENGINE_ID, GossipMessage, RegisteredMessageValidator, MessageValidationData};
+
 use super::PolkadotProtocol;
 
 /// An executor suitable for dispatching async consensus tasks.
@@ -67,7 +69,7 @@ impl Executor for TaskExecutor {
 /// Basic functionality that a network has to fulfill.
 pub trait NetworkService: Send + Sync + 'static {
 	/// Get a stream of gossip messages for a given hash.
-	fn gossip_messages_for(&self, topic: Hash) -> mpsc::UnboundedReceiver<ConsensusMessage>;
+	fn gossip_messages_for(&self, topic: Hash) -> mpsc::UnboundedReceiver<Vec<u8>>;
 
 	/// Gossip a message on given topic.
 	fn gossip_message(&self, topic: Hash, message: Vec<u8>);
@@ -81,11 +83,11 @@ pub trait NetworkService: Send + Sync + 'static {
 }
 
 impl NetworkService for super::NetworkService {
-	fn gossip_messages_for(&self, topic: Hash) -> mpsc::UnboundedReceiver<ConsensusMessage> {
+	fn gossip_messages_for(&self, topic: Hash) -> mpsc::UnboundedReceiver<Vec<u8>> {
 		let (tx, rx) = std::sync::mpsc::channel();
 
 		self.with_gossip(move |gossip, _| {
-			let inner_rx = gossip.messages_for(topic);
+			let inner_rx = gossip.messages_for(POLKADOT_ENGINE_ID, topic);
 			let _ = tx.send(inner_rx);
 		});
 
@@ -96,14 +98,10 @@ impl NetworkService for super::NetworkService {
 	}
 
 	fn gossip_message(&self, topic: Hash, message: Vec<u8>) {
-		self.gossip_consensus_message(topic, message, false);
+		self.gossip_consensus_message(topic, POLKADOT_ENGINE_ID, message);
 	}
 
-	fn drop_gossip(&self, topic: Hash) {
-		self.with_gossip(move |gossip, _| {
-			gossip.collect_garbage_for_topic(topic);
-		})
-	}
+	fn drop_gossip(&self, _topic: Hash) { }
 
 	fn with_spec<F: Send + 'static>(&self, with: F)
 		where F: FnOnce(&mut PolkadotProtocol, &mut NetContext<Block>)
@@ -115,8 +113,7 @@ impl NetworkService for super::NetworkService {
 // task that processes all gossipped consensus messages,
 // checking signatures
 struct MessageProcessTask<P, E, N: NetworkService, T> {
-	inner_stream: mpsc::UnboundedReceiver<ConsensusMessage>,
-	parent_hash: Hash,
+	inner_stream: mpsc::UnboundedReceiver<Vec<u8>>,
 	table_router: Router<P, E, N, T>,
 }
 
@@ -127,19 +124,12 @@ impl<P, E, N, T> MessageProcessTask<P, E, N, T> where
 	N: NetworkService,
 	T: Clone + Executor + Send + 'static,
 {
-	fn process_message(&self, msg: ConsensusMessage) -> Option<Async<()>> {
-		use polkadot_validation::SignedStatement;
+	fn process_message(&self, msg: Vec<u8>) -> Option<Async<()>> {
+		debug!(target: "validation", "Processing consensus statement for live consensus");
 
-		debug!(target: "validation", "Processing validation statement for live session");
-		if let Some(statement) = SignedStatement::decode(&mut msg.as_slice()) {
-			if ::polkadot_validation::check_statement(
-				&statement.statement,
-				&statement.signature,
-				statement.sender,
-				&self.parent_hash
-			) {
-				self.table_router.import_statement(statement);
-			}
+		// statements are already checked by gossip validator.
+		if let Some(message) = GossipMessage::decode(&mut &msg[..]) {
+			self.table_router.import_statement(message.statement);
 		}
 
 		None
@@ -175,13 +165,20 @@ pub struct ValidationNetwork<P, E, N, T> {
 	network: Arc<N>,
 	api: Arc<P>,
 	executor: T,
+	message_validator: RegisteredMessageValidator,
 	exit: E,
 }
 
 impl<P, E, N, T> ValidationNetwork<P, E, N, T> {
-	/// Create a new validation session networking object.
-	pub fn new(network: Arc<N>, exit: E, api: Arc<P>, executor: T) -> Self {
-		ValidationNetwork { network, exit, api, executor }
+	/// Create a new consensus networking object.
+	pub fn new(
+		network: Arc<N>,
+		exit: E,
+		message_validator: RegisteredMessageValidator,
+		api: Arc<P>,
+		executor: T,
+	) -> Self {
+		ValidationNetwork { network, exit, message_validator, api, executor }
 	}
 }
 
@@ -192,6 +189,7 @@ impl<P, E: Clone, N, T: Clone> Clone for ValidationNetwork<P, E, N, T> {
 			exit: self.exit.clone(),
 			api: self.api.clone(),
 			executor: self.executor.clone(),
+			message_validator: self.message_validator.clone(),
 		}
 	}
 }
@@ -210,6 +208,7 @@ impl<P, E, N, T> ParachainNetwork for ValidationNetwork<P, E, N, T> where
 		&self,
 		table: Arc<SharedTable>,
 		outgoing: polkadot_validation::Outgoing,
+		authorities: &[SessionKey],
 	) -> Self::TableRouter {
 		let parent_hash = table.consensus_parent_hash().clone();
 
@@ -224,6 +223,7 @@ impl<P, E, N, T> ParachainNetwork for ValidationNetwork<P, E, N, T> where
 			parent_hash,
 			knowledge.clone(),
 			self.exit.clone(),
+			self.message_validator.clone(),
 		);
 
 		table_router.broadcast_egress(outgoing);
@@ -234,6 +234,12 @@ impl<P, E, N, T> ParachainNetwork for ValidationNetwork<P, E, N, T> where
 		let executor = self.executor.clone();
 		let exit = self.exit.clone();
 
+		// before requesting messages, note live consensus session.
+		self.message_validator.note_session(
+			parent_hash,
+			MessageValidationData { authorities: authorities.to_vec() },
+		);
+
 		// spin up a task in the background that processes all incoming statements
 		// TODO: propagate statements on a timer?
 		let inner_stream = self.network.gossip_messages_for(attestation_topic);
@@ -245,7 +251,6 @@ impl<P, E, N, T> ParachainNetwork for ValidationNetwork<P, E, N, T> where
 				});
 				let process_task = MessageProcessTask {
 					inner_stream,
-					parent_hash,
 					table_router: table_router_clone,
 				};
 
@@ -276,12 +281,14 @@ impl Future for AwaitingCollation {
 				.poll()
 				.map_err(|_| NetworkDown)
 		}
-		if let Ok(futures::Async::Ready(mut inner)) = self.outer.poll() {
-			let poll_result = inner.poll();
-			self.inner = Some(inner);
-			return poll_result.map_err(|_| NetworkDown)
+		match self.outer.poll() {
+			Ok(futures::Async::Ready(inner)) => {
+				self.inner = Some(inner);
+				self.poll()
+			},
+			Ok(futures::Async::NotReady) => Ok(futures::Async::NotReady),
+			Err(_) => Err(NetworkDown)
 		}
-		Ok(futures::Async::NotReady)
 	}
 }