Remove pallet::without_storage_info from bridge GRANDPA pallet (#1478)

* remove pallet::without_storage_info from bridge GRANDPA pallet

* StoredBridgedHeader

* spelling

* fix benchmarks

* MAX_BRIDGED_AUTHORITIES: 256 -> 2048

* Update modules/grandpa/src/storage_types.rs

Co-authored-by: Adrian Catangiu <adrian@parity.io>

* Update modules/grandpa/src/storage_types.rs

Co-authored-by: Adrian Catangiu <adrian@parity.io>

* moved max authorities + header size to chain primitives

* removed unused code

* new -> try_new

* fix benchmarks compilation

Co-authored-by: Adrian Catangiu <adrian@parity.io>

bridges/bin/millau/runtime/src/lib.rs

@@ -426,11 +426,25 @@ parameter_types! {
 	pub const HeadersToKeep: u32 = 7 * bp_rialto::DAYS as u32;
 }
 
+parameter_types! {
+	/// Maximal number of authorities at Rialto.
+	pub const MaxAuthoritiesAtRialto: u32 = bp_rialto::MAX_AUTHORITIES_COUNT;
+	/// Maximal size of SCALE-encoded Rialto header.
+	pub const MaxRialtoHeaderSize: u32 = bp_rialto::MAX_HEADER_SIZE;
+
+	/// Maximal number of authorities at Westend.
+	pub const MaxAuthoritiesAtWestend: u32 = bp_westend::MAX_AUTHORITIES_COUNT;
+	/// Maximal size of SCALE-encoded Westend header.
+	pub const MaxWestendHeaderSize: u32 = bp_westend::MAX_HEADER_SIZE;
+}
+
 pub type RialtoGrandpaInstance = ();
 impl pallet_bridge_grandpa::Config for Runtime {
 	type BridgedChain = bp_rialto::Rialto;
 	type MaxRequests = MaxRequests;
 	type HeadersToKeep = HeadersToKeep;
+	type MaxBridgedAuthorities = MaxAuthoritiesAtRialto;
+	type MaxBridgedHeaderSize = MaxRialtoHeaderSize;
 
 	type WeightInfo = pallet_bridge_grandpa::weights::BridgeWeight<Runtime>;
 }
@@ -440,6 +454,8 @@ impl pallet_bridge_grandpa::Config<WestendGrandpaInstance> for Runtime {
 	type BridgedChain = bp_westend::Westend;
 	type MaxRequests = MaxRequests;
 	type HeadersToKeep = HeadersToKeep;
+	type MaxBridgedAuthorities = MaxAuthoritiesAtWestend;
+	type MaxBridgedHeaderSize = MaxWestendHeaderSize;
 
 	type WeightInfo = pallet_bridge_grandpa::weights::BridgeWeight<Runtime>;
 }

bridges/bin/rialto-parachain/runtime/src/lib.rs

@@ -531,6 +531,11 @@ parameter_types! {
 	/// Assuming the worst case of every header being finalized, we will keep headers at least for a
 	/// week.
 	pub const HeadersToKeep: u32 = 7 * bp_millau::DAYS as u32;
+
+	/// Maximal number of authorities at Millau.
+	pub const MaxAuthoritiesAtMillau: u32 = bp_millau::MAX_AUTHORITIES_COUNT;
+	/// Maximal size of SCALE-encoded Millau header.
+	pub const MaxMillauHeaderSize: u32 = bp_millau::MAX_HEADER_SIZE;
 }
 
 pub type MillauGrandpaInstance = ();
@@ -538,6 +543,8 @@ impl pallet_bridge_grandpa::Config for Runtime {
 	type BridgedChain = bp_millau::Millau;
 	type MaxRequests = MaxRequests;
 	type HeadersToKeep = HeadersToKeep;
+	type MaxBridgedAuthorities = MaxAuthoritiesAtMillau;
+	type MaxBridgedHeaderSize = MaxMillauHeaderSize;
 	type WeightInfo = pallet_bridge_grandpa::weights::BridgeWeight<Runtime>;
 }
 

bridges/bin/rialto/runtime/src/lib.rs

@@ -417,6 +417,11 @@ parameter_types! {
 	/// Assuming the worst case of every header being finalized, we will keep headers at least for a
 	/// week.
 	pub const HeadersToKeep: u32 = 7 * bp_rialto::DAYS as u32;
+
+	/// Maximal number of authorities at Millau.
+	pub const MaxAuthoritiesAtMillau: u32 = bp_millau::MAX_AUTHORITIES_COUNT;
+	/// Maximal size of SCALE-encoded Millau header.
+	pub const MaxMillauHeaderSize: u32 = bp_millau::MAX_HEADER_SIZE;
 }
 
 pub type MillauGrandpaInstance = ();
@@ -424,6 +429,8 @@ impl pallet_bridge_grandpa::Config for Runtime {
 	type BridgedChain = bp_millau::Millau;
 	type MaxRequests = MaxRequests;
 	type HeadersToKeep = HeadersToKeep;
+	type MaxBridgedAuthorities = MaxAuthoritiesAtMillau;
+	type MaxBridgedHeaderSize = MaxMillauHeaderSize;
 	type WeightInfo = pallet_bridge_grandpa::weights::BridgeWeight<Runtime>;
 }
 

bridges/modules/grandpa/src/lib.rs

@@ -36,6 +36,8 @@
 // Runtime-generated enums
 #![allow(clippy::large_enum_variant)]
 
+use storage_types::{StoredAuthoritySet, StoredBridgedHeader};
+
 use bp_header_chain::{justification::GrandpaJustification, InitializationData};
 use bp_runtime::{BlockNumberOf, Chain, HashOf, HasherOf, HeaderOf, OwnedBridgeModule};
 use finality_grandpa::voter_set::VoterSet;
@@ -48,6 +50,7 @@ use sp_std::{boxed::Box, convert::TryInto};
 mod extension;
 #[cfg(test)]
 mod mock;
+mod storage_types;
 
 /// Module, containing weights for this pallet.
 pub mod weights;
@@ -102,12 +105,24 @@ pub mod pallet {
 		#[pallet::constant]
 		type HeadersToKeep: Get<u32>;
 
+		/// Max number of authorities at the bridged chain.
+		#[pallet::constant]
+		type MaxBridgedAuthorities: Get<u32>;
+		/// Maximal size (in bytes) of the SCALE-encoded bridged chain header.
+		///
+		/// This constant must be selected with care. The pallet requires mandatory headers to be
+		/// submitted to be able to proceed. Mandatory headers contain public keys of all GRANDPA
+		/// authorities. E.g. for 1024 authorities, the size of encoded keys will be at least 32 KB.
+		/// The same header may also contain other digest items as well, so some reserve here
+		/// is required.
+		#[pallet::constant]
+		type MaxBridgedHeaderSize: Get<u32>;
+
 		/// Weights gathered through benchmarking.
 		type WeightInfo: WeightInfo;
 	}
 
 	#[pallet::pallet]
-	#[pallet::without_storage_info]
 	pub struct Pallet<T, I = ()>(PhantomData<(T, I)>);
 
 	#[pallet::hooks]
@@ -180,12 +195,14 @@ pub mod pallet {
 
 			let authority_set = <CurrentAuthoritySet<T, I>>::get();
 			let set_id = authority_set.set_id;
-			verify_justification::<T, I>(&justification, hash, *number, authority_set)?;
+			verify_justification::<T, I>(&justification, hash, *number, authority_set.into())?;
 
 			let is_authorities_change_enacted =
 				try_enact_authority_change::<T, I>(&finality_target, set_id)?;
+			let finality_target =
+				StoredBridgedHeader::<T, I>::try_from_bridged_header(*finality_target)?;
 			<RequestCount<T, I>>::mutate(|count| *count += 1);
-			insert_header::<T, I>(*finality_target, hash);
+			insert_header::<T, I>(finality_target, hash);
 			log::info!(
 				target: LOG_TARGET,
 				"Successfully imported finalized header with hash {:?}!",
@@ -221,7 +238,7 @@ pub mod pallet {
 
 			let init_allowed = !<BestFinalized<T, I>>::exists();
 			ensure!(init_allowed, <Error<T, I>>::AlreadyInitialized);
-			initialize_bridge::<T, I>(init_data.clone());
+			initialize_bridge::<T, I>(init_data.clone())?;
 
 			log::info!(
 				target: LOG_TARGET,
@@ -286,12 +303,12 @@ pub mod pallet {
 	/// Headers which have been imported into the pallet.
 	#[pallet::storage]
 	pub type ImportedHeaders<T: Config<I>, I: 'static = ()> =
-		StorageMap<_, Identity, BridgedBlockHash<T, I>, BridgedHeader<T, I>>;
+		StorageMap<_, Identity, BridgedBlockHash<T, I>, StoredBridgedHeader<T, I>>;
 
 	/// The current GRANDPA Authority set.
 	#[pallet::storage]
 	pub(super) type CurrentAuthoritySet<T: Config<I>, I: 'static = ()> =
-		StorageValue<_, bp_header_chain::AuthoritySet, ValueQuery>;
+		StorageValue<_, StoredAuthoritySet<T, I>, ValueQuery>;
 
 	/// Optional pallet owner.
 	///
@@ -333,7 +350,7 @@ pub mod pallet {
 			}
 
 			if let Some(init_data) = self.init_data.clone() {
-				initialize_bridge::<T, I>(init_data);
+				initialize_bridge::<T, I>(init_data).expect("genesis config is correct; qed");
 			} else {
 				// Since the bridge hasn't been initialized we shouldn't allow anyone to perform
 				// transactions.
@@ -364,6 +381,10 @@ pub mod pallet {
 		AlreadyInitialized,
 		/// The storage proof doesn't contains storage root. So it is invalid for given header.
 		StorageRootMismatch,
+		/// Too many authorities in the set.
+		TooManyAuthoritiesInSet,
+		/// Too large header.
+		TooLargeHeader,
 		/// Error generated by the `OwnedBridgeModule` trait.
 		BridgeModule(bp_runtime::OwnedBridgeModuleError),
 	}
@@ -392,8 +413,11 @@ pub mod pallet {
 			ensure!(change.delay == Zero::zero(), <Error<T, I>>::UnsupportedScheduledChange);
 
 			// TODO [#788]: Stop manually increasing the `set_id` here.
-			let next_authorities = bp_header_chain::AuthoritySet {
+			let next_authorities = StoredAuthoritySet::<T, I> {
-				authorities: change.next_authorities,
+				authorities: change
+					.next_authorities
+					.try_into()
+					.map_err(|_| Error::<T, I>::TooManyAuthoritiesInSet)?,
 				set_id: current_set_id + 1,
 			};
 
@@ -454,7 +478,7 @@ pub mod pallet {
 	/// Note this function solely takes care of updating the storage and pruning old entries,
 	/// but does not verify the validity of such import.
 	pub(crate) fn insert_header<T: Config<I>, I: 'static>(
-		header: BridgedHeader<T, I>,
+		header: StoredBridgedHeader<T, I>,
 		hash: BridgedBlockHash<T, I>,
 	) {
 		let index = <ImportedHashesPointer<T, I>>::get();
@@ -475,19 +499,23 @@ pub mod pallet {
 	/// were called by a trusted origin.
 	pub(crate) fn initialize_bridge<T: Config<I>, I: 'static>(
 		init_params: super::InitializationData<BridgedHeader<T, I>>,
-	) {
+	) -> Result<(), Error<T, I>> {
 		let super::InitializationData { header, authority_list, set_id, operating_mode } =
 			init_params;
+		let authority_set = StoredAuthoritySet::<T, I>::try_new(authority_list, set_id)
+			.map_err(|_| Error::TooManyAuthoritiesInSet)?;
+		let header = StoredBridgedHeader::<T, I>::try_from_bridged_header(*header)?;
 
 		let initial_hash = header.hash();
 		<InitialHash<T, I>>::put(initial_hash);
 		<ImportedHashesPointer<T, I>>::put(0);
-		insert_header::<T, I>(*header, initial_hash);
+		insert_header::<T, I>(header, initial_hash);
 
-		let authority_set = bp_header_chain::AuthoritySet::new(authority_list, set_id);
 		<CurrentAuthoritySet<T, I>>::put(authority_set);
 
 		<PalletOperatingMode<T, I>>::put(operating_mode);
+
+		Ok(())
 	}
 
 	#[cfg(feature = "runtime-benchmarks")]
@@ -496,7 +524,7 @@ pub mod pallet {
 	) {
 		let start_number = *init_params.header.number();
 		let end_number = start_number + T::HeadersToKeep::get().into();
-		initialize_bridge::<T, I>(init_params);
+		initialize_bridge::<T, I>(init_params).expect("benchmarks are correct");
 
 		let mut number = start_number;
 		while number < end_number {
@@ -509,7 +537,11 @@ pub mod pallet {
 				Default::default(),
 			);
 			let hash = header.hash();
-			insert_header::<T, I>(header, hash);
+			insert_header::<T, I>(
+				StoredBridgedHeader::try_from_bridged_header(header)
+					.expect("only used from benchmarks; benchmarks are correct; qed"),
+				hash,
+			);
 		}
 	}
 }
@@ -521,7 +553,7 @@ impl<T: Config<I>, I: 'static> Pallet<T, I> {
 	/// if the pallet has not been initialized yet.
 	pub fn best_finalized() -> Option<BridgedHeader<T, I>> {
 		let (_, hash) = <BestFinalized<T, I>>::get()?;
-		<ImportedHeaders<T, I>>::get(hash)
+		<ImportedHeaders<T, I>>::get(hash).map(|h| h.0)
 	}
 
 	/// Check if a particular header is known to the bridge pallet.
@@ -591,13 +623,17 @@ pub fn initialize_for_benchmarks<T: Config<I>, I: 'static>(header: BridgedHeader
 		                                          * benchmarks */
 		set_id: 0,
 		operating_mode: bp_runtime::BasicOperatingMode::Normal,
-	});
+	})
+	.expect("only used from benchmarks; benchmarks are correct; qed");
 }
 
 #[cfg(test)]
 mod tests {
 	use super::*;
-	use crate::mock::{run_test, test_header, Origin, TestHeader, TestNumber, TestRuntime};
+	use crate::mock::{
+		run_test, test_header, Origin, TestHeader, TestNumber, TestRuntime,
+		MAX_BRIDGED_AUTHORITIES, MAX_HEADER_SIZE,
+	};
 	use bp_runtime::BasicOperatingMode;
 	use bp_test_utils::{
 		authority_list, generate_owned_bridge_module_tests, make_default_justification,
@@ -673,6 +709,22 @@ mod tests {
 		Digest { logs: vec![DigestItem::Consensus(GRANDPA_ENGINE_ID, consensus_log.encode())] }
 	}
 
+	fn many_authorities_log() -> Digest {
+		let consensus_log =
+			ConsensusLog::<TestNumber>::ScheduledChange(sp_finality_grandpa::ScheduledChange {
+				next_authorities: std::iter::repeat((ALICE.into(), 1))
+					.take(MAX_BRIDGED_AUTHORITIES as usize + 1)
+					.collect(),
+				delay: 0,
+			});
+
+		Digest { logs: vec![DigestItem::Consensus(GRANDPA_ENGINE_ID, consensus_log.encode())] }
+	}
+
+	fn large_digest() -> Digest {
+		Digest { logs: vec![DigestItem::Other(vec![42; MAX_HEADER_SIZE as _])] }
+	}
+
 	#[test]
 	fn init_root_or_owner_origin_can_initialize_pallet() {
 		run_test(|| {
@@ -715,6 +767,45 @@ mod tests {
 		})
 	}
 
+	#[test]
+	fn init_fails_if_there_are_too_many_authorities_in_the_set() {
+		run_test(|| {
+			let genesis = test_header(0);
+			let init_data = InitializationData {
+				header: Box::new(genesis),
+				authority_list: std::iter::repeat(authority_list().remove(0))
+					.take(MAX_BRIDGED_AUTHORITIES as usize + 1)
+					.collect(),
+				set_id: 1,
+				operating_mode: BasicOperatingMode::Normal,
+			};
+
+			assert_noop!(
+				Pallet::<TestRuntime>::initialize(Origin::root(), init_data),
+				Error::<TestRuntime>::TooManyAuthoritiesInSet,
+			);
+		});
+	}
+
+	#[test]
+	fn init_fails_if_header_is_too_large() {
+		run_test(|| {
+			let mut genesis = test_header(0);
+			genesis.digest = large_digest();
+			let init_data = InitializationData {
+				header: Box::new(genesis),
+				authority_list: authority_list(),
+				set_id: 1,
+				operating_mode: BasicOperatingMode::Normal,
+			};
+
+			assert_noop!(
+				Pallet::<TestRuntime>::initialize(Origin::root(), init_data),
+				Error::<TestRuntime>::TooLargeHeader,
+			);
+		});
+	}
+
 	#[test]
 	fn pallet_rejects_transactions_if_halted() {
 		run_test(|| {
@@ -880,7 +971,8 @@ mod tests {
 			// Make sure that the authority set actually changed upon importing our header
 			assert_eq!(
 				<CurrentAuthoritySet<TestRuntime>>::get(),
-				bp_header_chain::AuthoritySet::new(next_authorities, next_set_id),
+				StoredAuthoritySet::<TestRuntime, ()>::try_new(next_authorities, next_set_id)
+					.unwrap(),
 			);
 		})
 	}
@@ -935,6 +1027,56 @@ mod tests {
 		})
 	}
 
+	#[test]
+	fn importing_header_rejects_header_with_too_many_authorities() {
+		run_test(|| {
+			initialize_substrate_bridge();
+
+			// Need to update the header digest to indicate that our header signals an authority set
+			// change. However, the change doesn't happen until the next block.
+			let mut header = test_header(2);
+			header.digest = many_authorities_log();
+
+			// Create a valid justification for the header
+			let justification = make_default_justification(&header);
+
+			// Should not be allowed to import this header
+			assert_err!(
+				Pallet::<TestRuntime>::submit_finality_proof(
+					Origin::signed(1),
+					Box::new(header),
+					justification
+				),
+				<Error<TestRuntime>>::TooManyAuthoritiesInSet
+			);
+		});
+	}
+
+	#[test]
+	fn importing_header_rejects_header_if_it_is_too_large() {
+		run_test(|| {
+			initialize_substrate_bridge();
+
+			// Need to update the header digest to indicate that our header signals an authority set
+			// change. However, the change doesn't happen until the next block.
+			let mut header = test_header(2);
+			header.digest = large_digest();
+
+			// Create a valid justification for the header
+			let justification = make_default_justification(&header);
+
+			// Should not be allowed to import this header
+			assert_err!(
+				Pallet::<TestRuntime>::submit_finality_proof(
+					Origin::signed(1),
+					Box::new(header),
+					justification
+				),
+				<Error<TestRuntime>>::TooLargeHeader
+			);
+		});
+	}
+
 	#[test]
 	fn parse_finalized_storage_proof_rejects_proof_on_unknown_header() {
 		run_test(|| {
@@ -959,7 +1101,10 @@ mod tests {
 
 			let hash = header.hash();
 			<BestFinalized<TestRuntime>>::put((2, hash));
-			<ImportedHeaders<TestRuntime>>::insert(hash, header);
+			<ImportedHeaders<TestRuntime>>::insert(
+				hash,
+				StoredBridgedHeader::try_from_bridged_header(header).unwrap(),
+			);
 
 			assert_ok!(
 				Pallet::<TestRuntime>::parse_finalized_storage_proof(hash, storage_proof, |_| (),),

bridges/modules/grandpa/src/mock.rs

@@ -33,6 +33,9 @@ pub type TestNumber = crate::BridgedBlockNumber<TestRuntime, ()>;
 type Block = frame_system::mocking::MockBlock<TestRuntime>;
 type UncheckedExtrinsic = frame_system::mocking::MockUncheckedExtrinsic<TestRuntime>;
 
+pub const MAX_BRIDGED_AUTHORITIES: u32 = 2048;
+pub const MAX_HEADER_SIZE: u32 = 65536;
+
 use crate as grandpa;
 
 construct_runtime! {
@@ -91,6 +94,8 @@ impl grandpa::Config for TestRuntime {
 	type BridgedChain = TestBridgedChain;
 	type MaxRequests = MaxRequests;
 	type HeadersToKeep = HeadersToKeep;
+	type MaxBridgedAuthorities = frame_support::traits::ConstU32<MAX_BRIDGED_AUTHORITIES>;
+	type MaxBridgedHeaderSize = frame_support::traits::ConstU32<MAX_HEADER_SIZE>;
 	type WeightInfo = ();
 }
 

bridges/modules/grandpa/src/storage_types.rs

@@ -0,0 +1,106 @@
+// Copyright 2022 Parity Technologies (UK) Ltd.
+// This file is part of Parity Bridges Common.
+
+// Parity Bridges Common is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity Bridges Common is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity Bridges Common.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Wrappers for public types that are implementing `MaxEncodedLen`
+
+use crate::{BridgedHeader, Config, Error};
+
+use bp_header_chain::AuthoritySet;
+use codec::{Decode, Encode, MaxEncodedLen};
+use frame_support::{traits::Get, BoundedVec, RuntimeDebugNoBound};
+use scale_info::{Type, TypeInfo};
+use sp_finality_grandpa::{AuthorityId, AuthorityList, AuthorityWeight, SetId};
+
+/// A bounded list of Grandpa authorities with associated weights.
+pub type StoredAuthorityList<MaxBridgedAuthorities> =
+	BoundedVec<(AuthorityId, AuthorityWeight), MaxBridgedAuthorities>;
+
+/// A bounded GRANDPA Authority List and ID.
+#[derive(Clone, Decode, Encode, Eq, TypeInfo, MaxEncodedLen, RuntimeDebugNoBound)]
+#[scale_info(skip_type_params(T, I))]
+pub struct StoredAuthoritySet<T: Config<I>, I: 'static> {
+	/// List of GRANDPA authorities for the current round.
+	pub authorities: StoredAuthorityList<<T as Config<I>>::MaxBridgedAuthorities>,
+	/// Monotonic identifier of the current GRANDPA authority set.
+	pub set_id: SetId,
+}
+
+impl<T: Config<I>, I: 'static> StoredAuthoritySet<T, I> {
+	/// Try to create a new bounded GRANDPA Authority Set from unbounded list.
+	///
+	/// Returns error if number of authorities in the provided list is too large.
+	pub fn try_new(authorities: AuthorityList, set_id: SetId) -> Result<Self, ()> {
+		Ok(Self { authorities: TryFrom::try_from(authorities)?, set_id })
+	}
+}
+
+impl<T: Config<I>, I: 'static> PartialEq for StoredAuthoritySet<T, I> {
+	fn eq(&self, other: &Self) -> bool {
+		self.set_id == other.set_id && self.authorities == other.authorities
+	}
+}
+
+impl<T: Config<I>, I: 'static> Default for StoredAuthoritySet<T, I> {
+	fn default() -> Self {
+		StoredAuthoritySet { authorities: BoundedVec::default(), set_id: 0 }
+	}
+}
+
+impl<T: Config<I>, I: 'static> From<StoredAuthoritySet<T, I>> for AuthoritySet {
+	fn from(t: StoredAuthoritySet<T, I>) -> Self {
+		AuthoritySet { authorities: t.authorities.into(), set_id: t.set_id }
+	}
+}
+
+/// A bounded chain header.
+#[derive(Clone, Decode, Encode, Eq, PartialEq, RuntimeDebugNoBound)]
+pub struct StoredBridgedHeader<T: Config<I>, I: 'static>(pub BridgedHeader<T, I>);
+
+impl<T: Config<I>, I: 'static> StoredBridgedHeader<T, I> {
+	/// Construct `StoredBridgedHeader` from the `BridgedHeader` with all required checks.
+	pub fn try_from_bridged_header(header: BridgedHeader<T, I>) -> Result<Self, Error<T, I>> {
+		// this conversion is heavy (since we do encoding here), so we may want to optimize it later
+		// (e.g. by introducing custom Encode implementation, and turning `StoredBridgedHeader` into
+		// `enum StoredBridgedHeader { Decoded(BridgedHeader), Encoded(Vec<u8>) }`)
+		if header.encoded_size() > T::MaxBridgedHeaderSize::get() as usize {
+			Err(Error::TooLargeHeader)
+		} else {
+			Ok(StoredBridgedHeader(header))
+		}
+	}
+}
+
+impl<T: Config<I>, I: 'static> sp_std::ops::Deref for StoredBridgedHeader<T, I> {
+	type Target = BridgedHeader<T, I>;
+
+	fn deref(&self) -> &Self::Target {
+		&self.0
+	}
+}
+
+impl<T: Config<I>, I: 'static> TypeInfo for StoredBridgedHeader<T, I> {
+	type Identity = Self;
+
+	fn type_info() -> Type {
+		BridgedHeader::<T, I>::type_info()
+	}
+}
+
+impl<T: Config<I>, I: 'static> MaxEncodedLen for StoredBridgedHeader<T, I> {
+	fn max_encoded_len() -> usize {
+		T::MaxBridgedHeaderSize::get() as usize
+	}
+}

bridges/modules/parachains/src/mock.rs

@@ -95,6 +95,8 @@ impl pallet_bridge_grandpa::Config<pallet_bridge_grandpa::Instance1> for TestRun
 	type BridgedChain = TestBridgedChain;
 	type MaxRequests = MaxRequests;
 	type HeadersToKeep = HeadersToKeep;
+	type MaxBridgedAuthorities = frame_support::traits::ConstU32<5>;
+	type MaxBridgedHeaderSize = frame_support::traits::ConstU32<512>;
 	type WeightInfo = ();
 }
 
@@ -102,6 +104,8 @@ impl pallet_bridge_grandpa::Config<pallet_bridge_grandpa::Instance2> for TestRun
 	type BridgedChain = TestBridgedChain;
 	type MaxRequests = MaxRequests;
 	type HeadersToKeep = HeadersToKeep;
+	type MaxBridgedAuthorities = frame_support::traits::ConstU32<5>;
+	type MaxBridgedHeaderSize = frame_support::traits::ConstU32<512>;
 	type WeightInfo = ();
 }
 

bridges/primitives/chain-millau/src/lib.rs

@@ -109,6 +109,12 @@ pub const PAY_INBOUND_DISPATCH_FEE_WEIGHT: Weight = 700_000_000;
 /// conditions.
 pub const SESSION_LENGTH: BlockNumber = 5 * time_units::MINUTES;
 
+/// Maximal number of GRANDPA authorities at Millau.
+pub const MAX_AUTHORITIES_COUNT: u32 = 5;
+
+/// Maximal SCALE-encoded header size (in bytes) at Millau.
+pub const MAX_HEADER_SIZE: u32 = 512;
+
 /// Re-export `time_units` to make usage easier.
 pub use time_units::*;
 

bridges/primitives/chain-rialto/src/lib.rs

@@ -100,6 +100,12 @@ pub const PAY_INBOUND_DISPATCH_FEE_WEIGHT: Weight = 700_000_000;
 /// conditions.
 pub const SESSION_LENGTH: BlockNumber = 4;
 
+/// Maximal number of GRANDPA authorities at Rialto.
+pub const MAX_AUTHORITIES_COUNT: u32 = 5;
+
+/// Maximal SCALE-encoded header size (in bytes) at Rialto.
+pub const MAX_HEADER_SIZE: u32 = 512;
+
 /// Re-export `time_units` to make usage easier.
 pub use time_units::*;
 

bridges/primitives/chain-westend/src/lib.rs

@@ -58,6 +58,18 @@ pub const WITH_WESTEND_BRIDGE_PARAS_PALLET_NAME: &str = "BridgeWestendParachains
 /// conditions.
 pub const SESSION_LENGTH: BlockNumber = 10 * time_units::MINUTES;
 
+/// Maximal number of GRANDPA authorities at Westend.
+///
+/// Corresponds to the `MaxAuthorities` constant value from the Westend runtime configuration.
+pub const MAX_AUTHORITIES_COUNT: u32 = 100_000;
+
+/// Maximal SCALE-encoded header size (in bytes) at Westend.
+///
+/// Let's assume that the largest header is header that enacts new authorities set with
+/// `MAX_AUTHORITES_COUNT`. Every authority means 32-byte key and 8-byte weight. Let's also have
+/// some fixed reserve for other things (digest, block hash and number, ...) as well.
+pub const MAX_HEADER_SIZE: u32 = 4096 + MAX_AUTHORITIES_COUNT * 40;
+
 /// Identifier of Westmint parachain at the Westend relay chain.
 pub const WESTMINT_PARACHAIN_ID: u32 = 2000;
 

bridges/primitives/header-chain/src/lib.rs

@@ -71,47 +71,6 @@ pub struct InitializationData<H: HeaderT> {
 	pub operating_mode: BasicOperatingMode,
 }
 
-/// base trait for verifying transaction inclusion proofs.
-pub trait InclusionProofVerifier {
-	/// Transaction type.
-	type Transaction: Parameter;
-	/// Transaction inclusion proof type.
-	type TransactionInclusionProof: Parameter;
-
-	/// Verify that transaction is a part of given block.
-	///
-	/// Returns Some(transaction) if proof is valid and None otherwise.
-	fn verify_transaction_inclusion_proof(
-		proof: &Self::TransactionInclusionProof,
-	) -> Option<Self::Transaction>;
-}
-
-/// A trait for pallets which want to keep track of finalized headers from a bridged chain.
-pub trait HeaderChain<H, E> {
-	/// Get the best finalized header known to the header chain.
-	fn best_finalized() -> Option<H>;
-
-	/// Get the best authority set known to the header chain.
-	fn authority_set() -> AuthoritySet;
-
-	/// Write a header finalized by GRANDPA to the underlying pallet storage.
-	fn append_header(header: H) -> Result<(), E>;
-}
-
-impl<H: Default, E> HeaderChain<H, E> for () {
-	fn best_finalized() -> Option<H> {
-		None
-	}
-
-	fn authority_set() -> AuthoritySet {
-		AuthoritySet::default()
-	}
-
-	fn append_header(_header: H) -> Result<(), E> {
-		Ok(())
-	}
-}
-
 /// Abstract finality proof that is justifying block finality.
 pub trait FinalityProof<Number>: Clone + Send + Sync + Debug {
 	/// Return number of header that this proof is generated for.

bridges/primitives/runtime/src/chain.rs

@@ -15,7 +15,7 @@
 // along with Parity Bridges Common.  If not, see <http://www.gnu.org/licenses/>.
 
 use crate::HeaderIdProvider;
-use codec::{Decode, Encode};
+use codec::{Decode, Encode, MaxEncodedLen};
 use frame_support::{weights::Weight, Parameter};
 use num_traits::{AsPrimitive, Bounded, CheckedSub, Saturating, SaturatingAdd, Zero};
 use sp_runtime::{
@@ -111,6 +111,7 @@ pub trait Chain: Send + Sync + 'static {
 		+ AsPrimitive<usize>
 		+ Default
 		+ Saturating
+		+ MaxEncodedLen
 		// original `sp_runtime::traits::Header::BlockNumber` doesn't have this trait, but
 		// `sp_runtime::generic::Era` requires block number -> `u64` conversion.
 		+ Into<u64>;
@@ -130,7 +131,8 @@ pub trait Chain: Send + Sync + 'static {
 		+ SimpleBitOps
 		+ AsRef<[u8]>
 		+ AsMut<[u8]>
-		+ MaybeMallocSizeOf;
+		+ MaybeMallocSizeOf
+		+ MaxEncodedLen;
 
 	/// A type that fulfills the abstract idea of what a Substrate hasher (a type
 	/// that produces hashes) is.
@@ -148,7 +150,13 @@ pub trait Chain: Send + Sync + 'static {
 		+ MaybeSerializeDeserialize;
 
 	/// The user account identifier type for the runtime.
-	type AccountId: Parameter + Member + MaybeSerializeDeserialize + Debug + MaybeDisplay + Ord;
+	type AccountId: Parameter
+		+ Member
+		+ MaybeSerializeDeserialize
+		+ Debug
+		+ MaybeDisplay
+		+ Ord
+		+ MaxEncodedLen;
 	/// Balance of an account in native tokens.
 	///
 	/// The chain may support multiple tokens, but this particular type is for token that is used
@@ -165,7 +173,8 @@ pub trait Chain: Send + Sync + 'static {
 		+ PartialOrd
 		+ SaturatingAdd
 		+ Zero
-		+ TryFrom<sp_core::U256>;
+		+ TryFrom<sp_core::U256>
+		+ MaxEncodedLen;
 	/// Index of a transaction used by the chain.
 	type Index: Parameter
 		+ Member
@@ -175,7 +184,8 @@ pub trait Chain: Send + Sync + 'static {
 		+ MaybeDisplay
 		+ MaybeSerializeDeserialize
 		+ AtLeast32Bit
-		+ Copy;
+		+ Copy
+		+ MaxEncodedLen;
 	/// Signature type, used on this chain.
 	type Signature: Parameter + Verify;