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/Cargo.lock

@@ -5461,6 +5461,7 @@ dependencies = [
  "polkadot-primitives",
  "sp-core",
  "sp-keyring",
+ "sp-runtime",
  "thiserror",
  "tracing",
 ]

polkadot/node/network/bridge/src/lib.rs

@@ -1306,7 +1306,8 @@ mod tests {
 			// peer A gets reported for sending a collation message.
 
 			let collator_protocol_message = protocol_v1::CollatorProtocolMessage::Declare(
-				Sr25519Keyring::Alice.public().into()
+				Sr25519Keyring::Alice.public().into(),
+				Default::default(),
 			);
 
 			let message = protocol_v1::CollationProtocol::CollatorProtocol(
@@ -1572,7 +1573,8 @@ mod tests {
 
 			{
 				let collator_protocol_message = protocol_v1::CollatorProtocolMessage::Declare(
-					Sr25519Keyring::Alice.public().into()
+					Sr25519Keyring::Alice.public().into(),
+					Default::default(),
 				);
 
 				let message = protocol_v1::CollationProtocol::CollatorProtocol(

polkadot/node/network/collator-protocol/Cargo.toml

@@ -5,17 +5,20 @@ authors = ["Parity Technologies <admin@parity.io>"]
 edition = "2018"
 
 [dependencies]
+always-assert = "0.1.2"
 futures = "0.3.12"
-tracing = "0.1.25"
-thiserror = "1.0.23"
 futures-timer = "3"
+thiserror = "1.0.23"
+tracing = "0.1.25"
+
+sp-core = { package = "sp-core", git = "https://github.com/paritytech/substrate", branch = "master" }
+sp-runtime = { package = "sp-runtime", git = "https://github.com/paritytech/substrate", branch = "master" }
 
 polkadot-primitives = { path = "../../../primitives" }
 polkadot-node-network-protocol = { path = "../../network/protocol" }
 polkadot-node-primitives = { path = "../../primitives" }
 polkadot-node-subsystem-util = { path = "../../subsystem-util" }
 polkadot-subsystem = { package = "polkadot-node-subsystem", path = "../../subsystem" }
-always-assert = "0.1.2"
 
 [dev-dependencies]
 log = "0.4.13"

polkadot/node/network/collator-protocol/src/collator_side.rs

@@ -19,11 +19,11 @@ use std::collections::{HashMap, HashSet};
 use super::{LOG_TARGET,  Result};
 
 use futures::{select, FutureExt, channel::oneshot};
+use sp_core::Pair;
 
 use polkadot_primitives::v1::{
-	CandidateHash, CandidateReceipt, CollatorId, CompressedPoV, CoreIndex,
-	CoreState, Hash, Id as ParaId,
-	PoV, ValidatorId
+	CandidateHash, CandidateReceipt, CollatorPair, CompressedPoV, CoreIndex, CoreState, Hash,
+	Id as ParaId, PoV, ValidatorId
 };
 use polkadot_subsystem::{
 	jaeger, PerLeafSpan,
@@ -209,10 +209,12 @@ struct Collation {
 	status: CollationStatus,
 }
 
-#[derive(Default)]
 struct State {
-	/// Our id.
-	our_id: CollatorId,
+	/// Our network peer id.
+	local_peer_id: PeerId,
+
+	/// Our collator pair.
+	collator_pair: CollatorPair,
 
 	/// The para this collator is collating on.
 	/// Starts as `None` and is updated with every `CollateOn` message.
@@ -250,6 +252,25 @@ struct State {
 }
 
 impl State {
+	/// Creates a new `State` instance with the given parameters and setting all remaining
+	/// state fields to their default values (i.e. empty).
+	fn new(local_peer_id: PeerId, collator_pair: CollatorPair, metrics: Metrics) -> State {
+		State {
+			local_peer_id,
+			collator_pair,
+			metrics,
+			collating_on: Default::default(),
+			peer_views: Default::default(),
+			view: Default::default(),
+			span_per_relay_parent: Default::default(),
+			collations: Default::default(),
+			collation_result_senders: Default::default(),
+			our_validators_groups: Default::default(),
+			declared_at: Default::default(),
+			connection_requests: Default::default(),
+		}
+	}
+
 	/// Returns `true` if the given `peer` is interested in the leaf that is represented by `relay_parent`.
 	fn peer_interested_in_leaf(&self, peer: &PeerId, relay_parent: &Hash) -> bool {
 		self.peer_views.get(peer).map(|v| v.contains(relay_parent)).unwrap_or(false)
@@ -407,7 +428,12 @@ async fn declare(
 	state: &mut State,
 	peer: PeerId,
 ) {
-	let wire_message = protocol_v1::CollatorProtocolMessage::Declare(state.our_id.clone());
+	let declare_signature_payload = protocol_v1::declare_signature_payload(&state.local_peer_id);
+
+	let wire_message = protocol_v1::CollatorProtocolMessage::Declare(
+		state.collator_pair.public(),
+		state.collator_pair.sign(&declare_signature_payload),
+	);
 
 	ctx.send_message(AllMessages::NetworkBridge(
 		NetworkBridgeMessage::SendCollationMessage(
@@ -490,7 +516,10 @@ async fn advertise_collation(
 		},
 	}
 
-	let wire_message = protocol_v1::CollatorProtocolMessage::AdvertiseCollation(relay_parent, collating_on);
+	let wire_message = protocol_v1::CollatorProtocolMessage::AdvertiseCollation(
+		relay_parent,
+		collating_on,
+	);
 
 	ctx.send_message(AllMessages::NetworkBridge(
 		NetworkBridgeMessage::SendCollationMessage(
@@ -676,7 +705,7 @@ async fn handle_incoming_peer_message(
 	use protocol_v1::CollatorProtocolMessage::*;
 
 	match msg {
-		Declare(_) => {
+		Declare(_, _) => {
 			tracing::warn!(
 				target: LOG_TARGET,
 				?origin,
@@ -861,20 +890,17 @@ async fn handle_our_view_change(
 }
 
 /// The collator protocol collator side main loop.
-#[tracing::instrument(skip(ctx, metrics), fields(subsystem = LOG_TARGET))]
+#[tracing::instrument(skip(ctx, collator_pair, metrics), fields(subsystem = LOG_TARGET))]
 pub(crate) async fn run(
 	mut ctx: impl SubsystemContext<Message = CollatorProtocolMessage>,
-	our_id: CollatorId,
+	local_peer_id: PeerId,
+	collator_pair: CollatorPair,
 	metrics: Metrics,
 ) -> Result<()> {
 	use FromOverseer::*;
 	use OverseerSignal::*;
 
-	let mut state = State {
-		metrics,
-		our_id,
-		..Default::default()
-	};
+	let mut state = State::new(local_peer_id, collator_pair, metrics);
 
 	loop {
 		select! {
@@ -907,27 +933,31 @@ pub(crate) async fn run(
 mod tests {
 	use super::*;
 
-	use std::{time::Duration, sync::Arc};
+	use std::{sync::Arc, time::Duration};
 
 	use assert_matches::assert_matches;
-	use futures::{executor, future, Future, channel::mpsc};
+	use futures::{channel::mpsc, executor, future, Future};
 
 	use sp_core::{crypto::Pair, Decode};
 	use sp_keyring::Sr25519Keyring;
+	use sp_runtime::traits::AppVerify;
 
-	use polkadot_primitives::v1::{
-		BlockData, CandidateDescriptor, CollatorPair, ScheduledCore,
-		ValidatorIndex, GroupRotationInfo, AuthorityDiscoveryId,
-		SessionIndex, SessionInfo,
-	};
-	use polkadot_subsystem::{ActiveLeavesUpdate, messages::{RuntimeApiMessage, RuntimeApiRequest}, jaeger};
-	use polkadot_node_subsystem_util::TimeoutExt;
-	use polkadot_subsystem_testhelpers as test_helpers;
 	use polkadot_node_network_protocol::{
 		our_view,
 		view,
 		request_response::request::IncomingRequest,
 	};
+	use polkadot_node_subsystem_util::TimeoutExt;
+	use polkadot_primitives::v1::{
+		AuthorityDiscoveryId, BlockData, CandidateDescriptor, CollatorPair, GroupRotationInfo,
+		ScheduledCore, SessionIndex, SessionInfo, ValidatorIndex,
+	};
+	use polkadot_subsystem::{
+		jaeger,
+		messages::{RuntimeApiMessage, RuntimeApiRequest},
+		ActiveLeavesUpdate,
+	};
+	use polkadot_subsystem_testhelpers as test_helpers;
 
 	#[derive(Default)]
 	struct TestCandidateBuilder {
@@ -961,7 +991,8 @@ mod tests {
 		validator_groups: (Vec<Vec<ValidatorIndex>>, GroupRotationInfo),
 		relay_parent: Hash,
 		availability_core: CoreState,
-		our_collator_pair: CollatorPair,
+		local_peer_id: PeerId,
+		collator_pair: CollatorPair,
 		session_index: SessionIndex,
 	}
 
@@ -1008,7 +1039,8 @@ mod tests {
 
 			let relay_parent = Hash::random();
 
-			let our_collator_pair = CollatorPair::generate().0;
+			let local_peer_id = PeerId::random();
+			let collator_pair = CollatorPair::generate().0;
 
 			Self {
 				para_id,
@@ -1019,7 +1051,8 @@ mod tests {
 				validator_groups,
 				relay_parent,
 				availability_core,
-				our_collator_pair,
+				local_peer_id,
+				collator_pair,
 				session_index: 1,
 			}
 		}
@@ -1094,7 +1127,8 @@ mod tests {
 	}
 
 	fn test_harness<T: Future<Output = ()>>(
-		collator_id: CollatorId,
+		local_peer_id: PeerId,
+		collator_pair: CollatorPair,
 		test: impl FnOnce(TestHarness) -> T,
 	) {
 		let _ = env_logger::builder()
@@ -1113,7 +1147,7 @@ mod tests {
 
 		let (context, virtual_overseer) = test_helpers::make_subsystem_context(pool.clone());
 
-		let subsystem = run(context, collator_id, Metrics::default());
+		let subsystem = run(context, local_peer_id, collator_pair, Metrics::default());
 
 		let test_fut = test(TestHarness { virtual_overseer });
 
@@ -1355,8 +1389,12 @@ mod tests {
 				assert_eq!(to[0], *peer);
 				assert_matches!(
 					wire_message,
-					protocol_v1::CollatorProtocolMessage::Declare(collator_id) => {
-						assert_eq!(collator_id, test_state.our_collator_pair.public());
+					protocol_v1::CollatorProtocolMessage::Declare(collator_id, signature) => {
+						assert!(signature.verify(
+							&*protocol_v1::declare_signature_payload(&test_state.local_peer_id),
+							&collator_id),
+						);
+						assert_eq!(collator_id, test_state.collator_pair.public());
 					}
 				);
 			}
@@ -1406,8 +1444,10 @@ mod tests {
 	#[test]
 	fn advertise_and_send_collation() {
 		let mut test_state = TestState::default();
+		let local_peer_id = test_state.local_peer_id.clone();
+		let collator_pair = test_state.collator_pair.clone();
 
-		test_harness(test_state.our_collator_pair.public(), |test_harness| async move {
+		test_harness(local_peer_id, collator_pair, |test_harness| async move {
 			let mut virtual_overseer = test_harness.virtual_overseer;
 
 			setup_system(&mut virtual_overseer, &test_state).await;
@@ -1520,8 +1560,10 @@ mod tests {
 	#[test]
 	fn collators_are_registered_correctly_at_validators() {
 		let test_state = TestState::default();
+		let local_peer_id = test_state.local_peer_id.clone();
+		let collator_pair = test_state.collator_pair.clone();
 
-		test_harness(test_state.our_collator_pair.public(), |test_harness| async move {
+		test_harness(local_peer_id, collator_pair, |test_harness| async move {
 			let mut virtual_overseer = test_harness.virtual_overseer;
 
 			let peer = test_state.validator_peer_id[0].clone();
@@ -1542,8 +1584,10 @@ mod tests {
 	#[test]
 	fn collations_are_only_advertised_to_validators_with_correct_view() {
 		let test_state = TestState::default();
+		let local_peer_id = test_state.local_peer_id.clone();
+		let collator_pair = test_state.collator_pair.clone();
 
-		test_harness(test_state.our_collator_pair.public(), |test_harness| async move {
+		test_harness(local_peer_id, collator_pair, |test_harness| async move {
 			let mut virtual_overseer = test_harness.virtual_overseer;
 
 			let peer = test_state.current_group_validator_peer_ids()[0].clone();
@@ -1583,8 +1627,10 @@ mod tests {
 	#[test]
 	fn collate_on_two_different_relay_chain_blocks() {
 		let mut test_state = TestState::default();
+		let local_peer_id = test_state.local_peer_id.clone();
+		let collator_pair = test_state.collator_pair.clone();
 
-		test_harness(test_state.our_collator_pair.public(), |test_harness| async move {
+		test_harness(local_peer_id, collator_pair, |test_harness| async move {
 			let mut virtual_overseer = test_harness.virtual_overseer;
 
 			let peer = test_state.current_group_validator_peer_ids()[0].clone();
@@ -1628,8 +1674,10 @@ mod tests {
 	#[test]
 	fn validator_reconnect_does_not_advertise_a_second_time() {
 		let test_state = TestState::default();
+		let local_peer_id = test_state.local_peer_id.clone();
+		let collator_pair = test_state.collator_pair.clone();
 
-		test_harness(test_state.our_collator_pair.public(), |test_harness| async move {
+		test_harness(local_peer_id, collator_pair, |test_harness| async move {
 			let mut virtual_overseer = test_harness.virtual_overseer;
 
 			let peer = test_state.current_group_validator_peer_ids()[0].clone();

polkadot/node/network/collator-protocol/src/lib.rs

@@ -25,20 +25,13 @@ use std::time::Duration;
 use futures::{channel::oneshot, FutureExt, TryFutureExt};
 use thiserror::Error;
 
+use polkadot_node_network_protocol::{PeerId, UnifiedReputationChange as Rep};
+use polkadot_node_subsystem_util::{self as util, metrics::prometheus};
+use polkadot_primitives::v1::CollatorPair;
 use polkadot_subsystem::{
-	Subsystem, SubsystemContext, SubsystemError, SpawnedSubsystem,
 	errors::RuntimeApiError,
-	messages::{
-		AllMessages, CollatorProtocolMessage, NetworkBridgeMessage,
-	},
-};
-use polkadot_node_network_protocol::{
-	PeerId, UnifiedReputationChange as Rep,
-};
-use polkadot_primitives::v1::CollatorId;
-use polkadot_node_subsystem_util::{
-	self as util,
-	metrics::prometheus,
+	messages::{AllMessages, CollatorProtocolMessage, NetworkBridgeMessage},
+	SpawnedSubsystem, Subsystem, SubsystemContext, SubsystemError,
 };
 
 mod collator_side;
@@ -77,7 +70,7 @@ pub enum ProtocolSide {
 	/// Validators operate on the relay chain.
 	Validator(CollatorEvictionPolicy, validator_side::Metrics),
 	/// Collators operate on a parachain.
-	Collator(CollatorId, collator_side::Metrics),
+	Collator(PeerId, CollatorPair, collator_side::Metrics),
 }
 
 /// The collator protocol subsystem.
@@ -107,9 +100,10 @@ impl CollatorProtocolSubsystem {
 				policy,
 				metrics,
 			).await,
-			ProtocolSide::Collator(id, metrics) => collator_side::run(
+			ProtocolSide::Collator(local_peer_id, collator_pair, metrics) => collator_side::run(
 				ctx,
-				id,
+				local_peer_id,
+				collator_pair,
 				metrics,
 			).await,
 		}.map_err(|e| {

polkadot/node/network/collator-protocol/src/validator_side.rs

@@ -16,34 +16,35 @@
 
 use std::{collections::{HashMap, HashSet}, sync::Arc, task::Poll};
 use std::time::{Duration, Instant};
-
-use futures::{FutureExt, channel::oneshot, future::{Fuse, FusedFuture, BoxFuture, Either}};
-use futures::StreamExt;
-use futures_timer::Delay;
 use always_assert::never;
+use futures::{
+	channel::oneshot, future::{BoxFuture, Either, Fuse, FusedFuture}, FutureExt, StreamExt,
+};
+use futures_timer::Delay;
 
-use polkadot_primitives::v1::{
-	Id as ParaId, CandidateReceipt, CollatorId, Hash, PoV,
-};
-use polkadot_subsystem::{
-	jaeger, PerLeafSpan,
-	FromOverseer, OverseerSignal, SubsystemContext,
-	messages::{
-		AllMessages, CandidateSelectionMessage, CollatorProtocolMessage, NetworkBridgeMessage,
-		NetworkBridgeEvent, IfDisconnected,
-	},
-};
 use polkadot_node_network_protocol::{
-	OurView, PeerId, UnifiedReputationChange as Rep, View,
+	request_response as req_res, v1 as protocol_v1,
 	peer_set::PeerSet,
-	request_response::{OutgoingRequest, Requests, request::{Recipient, RequestError}}, v1 as protocol_v1
+	request_response::{
+		request::{Recipient, RequestError},
+		v1::{CollationFetchingRequest, CollationFetchingResponse},
+		OutgoingRequest, Requests,
+	},
+	OurView, PeerId, UnifiedReputationChange as Rep, View,
 };
-use polkadot_node_network_protocol::request_response::v1::{CollationFetchingRequest, CollationFetchingResponse};
-use polkadot_node_network_protocol::request_response as req_res;
+use polkadot_node_primitives::{SignedFullStatement, Statement};
 use polkadot_node_subsystem_util::metrics::{self, prometheus};
-use polkadot_node_primitives::{Statement, SignedFullStatement};
+use polkadot_primitives::v1::{CandidateReceipt, CollatorId, Hash, Id as ParaId, PoV};
+use polkadot_subsystem::{
+	jaeger,
+	messages::{
+		AllMessages, CandidateSelectionMessage, CollatorProtocolMessage, IfDisconnected,
+		NetworkBridgeEvent, NetworkBridgeMessage,
+	},
+	FromOverseer, OverseerSignal, PerLeafSpan, SubsystemContext,
+};
 
-use super::{modify_reputation, LOG_TARGET, Result};
+use super::{modify_reputation, Result, LOG_TARGET};
 
 const COST_UNEXPECTED_MESSAGE: Rep = Rep::CostMinor("An unexpected message");
 /// Message could not be decoded properly.
@@ -51,6 +52,7 @@ const COST_CORRUPTED_MESSAGE: Rep = Rep::CostMinor("Message was corrupt");
 /// Network errors that originated at the remote host should have same cost as timeout.
 const COST_NETWORK_ERROR: Rep = Rep::CostMinor("Some network error");
 const COST_REQUEST_TIMED_OUT: Rep = Rep::CostMinor("A collation request has timed out");
+const COST_INVALID_SIGNATURE: Rep = Rep::Malicious("Invalid network message signature");
 const COST_REPORT_BAD: Rep = Rep::Malicious("A collator was reported by another subsystem");
 const BENEFIT_NOTIFY_GOOD: Rep = Rep::BenefitMinor("A collator was noted good by another subsystem");
 
@@ -422,13 +424,19 @@ where
 	Context: SubsystemContext<Message = CollatorProtocolMessage>
 {
 	use protocol_v1::CollatorProtocolMessage::*;
+	use sp_runtime::traits::AppVerify;
 
 	if let Some(d) = state.peer_data.get_mut(&origin) {
 		d.note_active();
 	}
 
 	match msg {
-		Declare(id) => {
+		Declare(id, signature) => {
+			if !signature.verify(&*protocol_v1::declare_signature_payload(&origin), &id) {
+				modify_reputation(ctx, origin, COST_INVALID_SIGNATURE).await;
+				return;
+			}
+
 			tracing::debug!(
 				target: LOG_TARGET,
 				peer_id = ?origin,
@@ -1015,7 +1023,6 @@ mod tests {
 				)
 			).await;
 
-
 			let peer_b = PeerId::random();
 
 			overseer_send(
@@ -1023,7 +1030,10 @@ mod tests {
 				CollatorProtocolMessage::NetworkBridgeUpdateV1(
 					NetworkBridgeEvent::PeerMessage(
 						peer_b.clone(),
-						protocol_v1::CollatorProtocolMessage::Declare(pair.public()),
+						protocol_v1::CollatorProtocolMessage::Declare(
+							pair.public(),
+							pair.sign(&protocol_v1::declare_signature_payload(&peer_b)),
+						)
 					)
 				)
 			).await;
@@ -1083,6 +1093,7 @@ mod tests {
 						peer_b.clone(),
 						protocol_v1::CollatorProtocolMessage::Declare(
 							test_state.collators[0].public(),
+							test_state.collators[0].sign(&protocol_v1::declare_signature_payload(&peer_b)),
 						),
 					)
 				)
@@ -1095,6 +1106,7 @@ mod tests {
 						peer_c.clone(),
 						protocol_v1::CollatorProtocolMessage::Declare(
 							test_state.collators[1].public(),
+							test_state.collators[1].sign(&protocol_v1::declare_signature_payload(&peer_c)),
 						),
 					)
 				)
@@ -1132,6 +1144,44 @@ mod tests {
 		});
 	}
 
+	// Test that we verify the signatures on `Declare` and `AdvertiseCollation` messages.
+	#[test]
+	fn collator_authentication_verification_works() {
+		let test_state = TestState::default();
+
+		test_harness(|test_harness| async move {
+			let TestHarness {
+				mut virtual_overseer,
+			} = test_harness;
+
+			let peer_b = PeerId::random();
+
+			// the peer sends a declare message but sign the wrong payload
+			overseer_send(
+				&mut virtual_overseer,
+				CollatorProtocolMessage::NetworkBridgeUpdateV1(NetworkBridgeEvent::PeerMessage(
+					peer_b.clone(),
+					protocol_v1::CollatorProtocolMessage::Declare(
+						test_state.collators[0].public(),
+						test_state.collators[0].sign(&[42]),
+					),
+				)),
+			)
+			.await;
+
+			// it should be reported for sending a message with an invalid signature
+			assert_matches!(
+				overseer_recv(&mut virtual_overseer).await,
+				AllMessages::NetworkBridge(
+					NetworkBridgeMessage::ReportPeer(peer, rep),
+				) => {
+					assert_eq!(peer, peer_b);
+					assert_eq!(rep, COST_INVALID_SIGNATURE);
+				}
+			);
+		});
+	}
+
 	// A test scenario that takes the following steps
 	//  - Two collators connect, declare themselves and advertise a collation relevant to
 	//    our view.
@@ -1167,6 +1217,7 @@ mod tests {
 						peer_b.clone(),
 						protocol_v1::CollatorProtocolMessage::Declare(
 							test_state.collators[0].public(),
+							test_state.collators[0].sign(&protocol_v1::declare_signature_payload(&peer_b)),
 						)
 					)
 				)
@@ -1179,6 +1230,7 @@ mod tests {
 						peer_c.clone(),
 						protocol_v1::CollatorProtocolMessage::Declare(
 							test_state.collators[1].public(),
+							test_state.collators[1].sign(&protocol_v1::declare_signature_payload(&peer_c)),
 						)
 					)
 				)
@@ -1366,7 +1418,10 @@ mod tests {
 				CollatorProtocolMessage::NetworkBridgeUpdateV1(
 					NetworkBridgeEvent::PeerMessage(
 						peer_b.clone(),
-						protocol_v1::CollatorProtocolMessage::Declare(pair.public()),
+						protocol_v1::CollatorProtocolMessage::Declare(
+							pair.public(),
+							pair.sign(&protocol_v1::declare_signature_payload(&peer_b)),
+						)
 					)
 				)
 			).await;
@@ -1455,7 +1510,10 @@ mod tests {
 				CollatorProtocolMessage::NetworkBridgeUpdateV1(
 					NetworkBridgeEvent::PeerMessage(
 						peer_b.clone(),
-						protocol_v1::CollatorProtocolMessage::Declare(pair.public()),
+						protocol_v1::CollatorProtocolMessage::Declare(
+							pair.public(),
+							pair.sign(&protocol_v1::declare_signature_payload(&peer_b)),
+						)
 					)
 				)
 			).await;

polkadot/node/network/protocol/src/lib.rs

@@ -288,15 +288,21 @@ impl View {
 
 /// v1 protocol types.
 pub mod v1 {
-	use polkadot_primitives::v1::{AvailableData, CandidateHash, CandidateIndex, CollatorId, CompressedPoV, ErasureChunk, Hash, Id as ParaId, SignedAvailabilityBitfield, ValidatorIndex};
-	use polkadot_node_primitives::{
-		SignedFullStatement,
-		approval::{IndirectAssignmentCert, IndirectSignedApprovalVote},
-	};
-	use parity_scale_codec::{Encode, Decode};
-	use super::RequestId;
 	use std::convert::TryFrom;
 
+	use parity_scale_codec::{Decode, Encode};
+
+	use super::RequestId;
+	use polkadot_node_primitives::{
+		approval::{IndirectAssignmentCert, IndirectSignedApprovalVote},
+		SignedFullStatement,
+	};
+	use polkadot_primitives::v1::{
+		AvailableData, CandidateHash, CandidateIndex, CollatorId, CompressedPoV,
+		CollatorSignature, ErasureChunk, Hash, Id as ParaId, SignedAvailabilityBitfield,
+		ValidatorIndex,
+	};
+
 	/// Network messages used by the availability recovery subsystem.
 	#[derive(Debug, Clone, Encode, Decode, PartialEq, Eq)]
 	pub enum AvailabilityRecoveryMessage {
@@ -357,11 +363,12 @@ pub mod v1 {
 	/// Network messages used by the collator protocol subsystem
 	#[derive(Debug, Clone, Encode, Decode, PartialEq, Eq)]
 	pub enum CollatorProtocolMessage {
-		/// Declare the intent to advertise collations under a collator ID.
+		/// Declare the intent to advertise collations under a collator ID, attaching a
+		/// signature of the `PeerId` of the node using the given collator ID key.
 		#[codec(index = 0)]
-		Declare(CollatorId),
-		/// Advertise a collation to a validator. Can only be sent once the peer has declared
-		/// that they are a collator with given ID.
+		Declare(CollatorId, CollatorSignature),
+		/// Advertise a collation to a validator. Can only be sent once the peer has
+		/// declared that they are a collator with given ID.
 		#[codec(index = 1)]
 		AdvertiseCollation(Hash, ParaId),
 		/// A collation sent to a validator was seconded.
@@ -404,4 +411,14 @@ pub mod v1 {
 	}
 
 	impl_try_from!(CollationProtocol, CollatorProtocol, CollatorProtocolMessage);
+
+	/// Get the payload that should be signed and included in a `Declare` message.
+	///
+	/// The payload is the local peer id of the node, which serves to prove that it
+	/// controls the collator key it is declaring an intention to collate under.
+	pub fn declare_signature_payload(peer_id: &sc_network::PeerId) -> Vec<u8> {
+		let mut payload = peer_id.to_bytes();
+		payload.extend_from_slice(b"COLL");
+		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?

polkadot/node/test/service/src/lib.rs

@@ -24,7 +24,7 @@ pub use chain_spec::*;
 use futures::future::Future;
 use polkadot_overseer::OverseerHandler;
 use polkadot_primitives::v1::{
-	Id as ParaId, HeadData, ValidationCode, Balance, CollatorPair, CollatorId,
+	Id as ParaId, HeadData, ValidationCode, Balance, CollatorPair,
 };
 use polkadot_runtime_common::BlockHashCount;
 use polkadot_service::{
@@ -250,12 +250,19 @@ pub fn run_collator_node(
 	key: Sr25519Keyring,
 	storage_update_func: impl Fn(),
 	boot_nodes: Vec<MultiaddrWithPeerId>,
-	collator_id: CollatorId,
+	collator_pair: CollatorPair,
 ) -> PolkadotTestNode {
 	let config = node_config(storage_update_func, task_executor, key, boot_nodes, false);
 	let multiaddr = config.network.listen_addresses[0].clone();
-	let NewFull { task_manager, client, network, rpc_handlers, overseer_handler, .. } =
-		new_full(config, IsCollator::Yes(collator_id)).expect("could not create Polkadot test service");
+	let NewFull {
+		task_manager,
+		client,
+		network,
+		rpc_handlers,
+		overseer_handler,
+		..
+	} = new_full(config, IsCollator::Yes(collator_pair))
+		.expect("could not create Polkadot test service");
 
 	let overseer_handler = overseer_handler.expect("test node must have an overseer handler");
 	let peer_id = network.local_peer_id().clone();

polkadot/parachain/test-parachains/adder/collator/src/main.rs

@@ -60,7 +60,7 @@ fn main() -> Result<()> {
 
 						let full_node = polkadot_service::build_full(
 							config,
-							polkadot_service::IsCollator::Yes(collator.collator_id()),
+							polkadot_service::IsCollator::Yes(collator.collator_key()),
 							None,
 							None,
 							None,

polkadot/parachain/test-parachains/adder/collator/tests/integration.rs

@@ -60,7 +60,7 @@ async fn collating_using_adder_collator(task_executor: sc_service::TaskExecutor)
 		Charlie,
 		|| {},
 		vec![alice.addr.clone(), bob.addr.clone()],
-		collator.collator_id(),
+		collator.collator_key(),
 	);
 
 	charlie.register_collator(

polkadot/roadmap/implementers-guide/src/types/network.md

@@ -102,10 +102,11 @@ enum StatementDistributionV1Message {
 
 ```rust
 enum CollatorProtocolV1Message {
-	/// Declare the intent to advertise collations under a collator ID.
-	Declare(CollatorId),
-	/// Advertise a collation to a validator. Can only be sent once the peer has declared
-	/// that they are a collator with given ID.
+	/// Declare the intent to advertise collations under a collator ID, attaching a
+	/// signature of the `PeerId` of the node using the given collator ID key.
+	Declare(CollatorId, CollatorSignature),
+	/// Advertise a collation to a validator. Can only be sent once the peer has
+	/// declared that they are a collator with given ID.
 	AdvertiseCollation(Hash, ParaId),
 	/// Request the advertised collation at that relay-parent.
 	RequestCollation(RequestId, Hash, ParaId),