collator-protocol: add message authentication (#2635)

* collator: authenticate collator protocol messages

* fix tests compilation

* node: verify collator protocol signatures in tests

* collator: fix tests

* implementers-guide: update CollatorProtocol messages

* collator: add test for verification of collator protocol signatures

* node: remove fixmes

* node: remove signature from advertisecollation message

* node: add magic constant to Declare message signature payload

polkadot/node/service/src/lib.rs

@@ -60,7 +60,7 @@ pub use self::client::{AbstractClient, Client, ClientHandle, ExecuteWithClient,
 pub use chain_spec::{PolkadotChainSpec, KusamaChainSpec, WestendChainSpec, RococoChainSpec};
 pub use consensus_common::{Proposal, SelectChain, BlockImport, block_validation::Chain};
 pub use polkadot_parachain::wasm_executor::IsolationStrategy;
-pub use polkadot_primitives::v1::{Block, BlockId, CollatorId, Hash, Id as ParaId};
+pub use polkadot_primitives::v1::{Block, BlockId, CollatorPair, Hash, Id as ParaId};
 pub use sc_client_api::{Backend, ExecutionStrategy, CallExecutor};
 pub use sc_consensus::LongestChain;
 pub use sc_executor::NativeExecutionDispatch;
@@ -502,7 +502,11 @@ where
 		),
 		collator_protocol: {
 			let side = match is_collator {
-				IsCollator::Yes(id) => ProtocolSide::Collator(id, Metrics::register(registry)?),
+				IsCollator::Yes(collator_pair) => ProtocolSide::Collator(
+					network_service.local_peer_id().clone(),
+					collator_pair,
+					Metrics::register(registry)?,
+				),
 				IsCollator::No => ProtocolSide::Validator(Default::default(),Metrics::register(registry)?),
 			};
 			CollatorProtocolSubsystem::new(
@@ -578,14 +582,25 @@ impl<C> NewFull<C> {
 
 /// Is this node a collator?
 #[cfg(feature = "full-node")]
-#[derive(Debug, PartialEq, Eq, Clone)]
+#[derive(Clone)]
 pub enum IsCollator {
 	/// This node is a collator.
-	Yes(CollatorId),
+	Yes(CollatorPair),
 	/// This node is not a collator.
 	No,
 }
 
+#[cfg(feature = "full-node")]
+impl std::fmt::Debug for IsCollator {
+	fn fmt(&self, fmt: &mut std::fmt::Formatter) -> std::fmt::Result {
+		use sp_core::Pair;
+		match self {
+			IsCollator::Yes(pair) => write!(fmt, "Yes({})", pair.public()),
+			IsCollator::No => write!(fmt, "No"),
+		}
+	}
+}
+
 #[cfg(feature = "full-node")]
 impl IsCollator {
 	/// Is this a collator?