when GRANDPA pallet is halted, relay shall not submit finality transa…

…ctions (paritytech#1288)

bridges/modules/grandpa/src/lib.rs

@@ -1151,6 +1151,11 @@ mod tests {
 
 	#[test]
 	fn storage_keys_computed_properly() {
+		assert_eq!(
+			IsHalted::<TestRuntime>::storage_value_final_key().to_vec(),
+			bp_header_chain::storage_keys::is_halted_key("Grandpa").0,
+		);
+
 		assert_eq!(
 			BestFinalized::<TestRuntime>::storage_value_final_key().to_vec(),
 			bp_header_chain::storage_keys::best_finalized_hash_key("Grandpa").0,

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

@@ -16,17 +16,30 @@
 
 //! Storage keys of bridge GRANDPA pallet.
 
-/// Name of the `BestFinalized` storage map.
-pub const BEST_FINALIZED_MAP_NAME: &str = "BestFinalized";
+/// Name of the `IsHalted` storage value.
+pub const IS_HALTED_VALUE_NAME: &str = "IsHalted";
+/// Name of the `BestFinalized` storage value.
+pub const BEST_FINALIZED_VALUE_NAME: &str = "BestFinalized";
 
 use sp_core::storage::StorageKey;
 
+/// Storage key of the `IsHalted` flag in the runtime storage.
+pub fn is_halted_key(pallet_prefix: &str) -> StorageKey {
+	StorageKey(
+		bp_runtime::storage_value_final_key(
+			pallet_prefix.as_bytes(),
+			IS_HALTED_VALUE_NAME.as_bytes(),
+		)
+		.to_vec(),
+	)
+}
+
 /// Storage key of the best finalized header hash value in the runtime storage.
 pub fn best_finalized_hash_key(pallet_prefix: &str) -> StorageKey {
 	StorageKey(
 		bp_runtime::storage_value_final_key(
 			pallet_prefix.as_bytes(),
-			BEST_FINALIZED_MAP_NAME.as_bytes(),
+			BEST_FINALIZED_VALUE_NAME.as_bytes(),
 		)
 		.to_vec(),
 	)
@@ -37,6 +50,19 @@ mod tests {
 	use super::*;
 	use hex_literal::hex;
 
+	#[test]
+	fn is_halted_key_computed_properly() {
+		// If this test fails, then something has been changed in module storage that is breaking
+		// compatibility with previous pallet.
+		let storage_key = is_halted_key("BridgeGrandpa").0;
+		assert_eq!(
+			storage_key,
+			hex!("0b06f475eddb98cf933a12262e0388de9611a984bbd04e2fd39f97bbc006115f").to_vec(),
+			"Unexpected storage key: {}",
+			hex::encode(&storage_key),
+		);
+	}
+
 	#[test]
 	fn best_finalized_hash_key_computed_properly() {
 		// If this test fails, then something has been changed in module storage that is breaking

bridges/relays/client-substrate/src/error.rs

@@ -51,6 +51,9 @@ pub enum Error {
 	/// The client we're connected to is not synced, so we can't rely on its state.
 	#[error("Substrate client is not synced {0}.")]
 	ClientNotSynced(Health),
+	/// The bridge pallet is halted and all transactions will be rejected.
+	#[error("Bridge pallet is halted.")]
+	BridgePalletIsHalted,
 	/// An error has happened when we have tried to parse storage proof.
 	#[error("Error when parsing storage proof: {0:?}.")]
 	StorageProofError(bp_runtime::StorageProofError),

bridges/relays/lib-substrate-relay/src/finality_pipeline.rs

@@ -27,8 +27,8 @@ use bp_header_chain::justification::GrandpaJustification;
 use finality_relay::FinalitySyncPipeline;
 use pallet_bridge_grandpa::{Call as BridgeGrandpaCall, Config as BridgeGrandpaConfig};
 use relay_substrate_client::{
-	transaction_stall_timeout, AccountIdOf, AccountKeyPairOf, BlockNumberOf, CallOf, Chain, Client,
-	HashOf, HeaderOf, SyncHeader, TransactionSignScheme,
+	transaction_stall_timeout, AccountIdOf, AccountKeyPairOf, BlockNumberOf, CallOf, Chain,
+	ChainWithGrandpa, Client, HashOf, HeaderOf, SyncHeader, TransactionSignScheme,
 };
 use relay_utils::metrics::MetricsParams;
 use sp_core::Pair;
@@ -44,7 +44,7 @@ pub(crate) const RECENT_FINALITY_PROOFS_LIMIT: usize = 4096;
 #[async_trait]
 pub trait SubstrateFinalitySyncPipeline: 'static + Clone + Debug + Send + Sync {
 	/// Headers of this chain are submitted to the `TargetChain`.
-	type SourceChain: Chain;
+	type SourceChain: ChainWithGrandpa;
 	/// Headers of the `SourceChain` are submitted to this chain.
 	type TargetChain: Chain;
 

bridges/relays/lib-substrate-relay/src/finality_target.rs

@@ -26,12 +26,12 @@ use crate::{
 };
 
 use async_trait::async_trait;
-use bp_header_chain::justification::GrandpaJustification;
+use bp_header_chain::{justification::GrandpaJustification, storage_keys::is_halted_key};
 use codec::Encode;
 use finality_relay::TargetClient;
 use relay_substrate_client::{
-	AccountIdOf, AccountKeyPairOf, BlockNumberOf, Chain, Client, Error, HashOf, HeaderOf,
-	SignParam, SyncHeader, TransactionEra, TransactionSignScheme, UnsignedTransaction,
+	AccountIdOf, AccountKeyPairOf, BlockNumberOf, Chain, ChainWithGrandpa, Client, Error, HashOf,
+	HeaderOf, SignParam, SyncHeader, TransactionEra, TransactionSignScheme, UnsignedTransaction,
 };
 use relay_utils::relay_loop::Client as RelayClient;
 use sp_core::{Bytes, Pair};
@@ -50,6 +50,19 @@ impl<P: SubstrateFinalitySyncPipeline> SubstrateFinalityTarget<P> {
 	) -> Self {
 		SubstrateFinalityTarget { client, transaction_params }
 	}
+
+	/// Ensure that the GRANDPA pallet at target chain is active.
+	async fn ensure_pallet_active(&self) -> Result<(), Error> {
+		let is_halted = self
+			.client
+			.storage_value(is_halted_key(P::SourceChain::WITH_CHAIN_GRANDPA_PALLET_NAME), None)
+			.await?;
+		if is_halted.unwrap_or(false) {
+			Err(Error::BridgePalletIsHalted)
+		} else {
+			Ok(())
+		}
+	}
 }
 
 impl<P: SubstrateFinalitySyncPipeline> Clone for SubstrateFinalityTarget<P> {
@@ -83,6 +96,8 @@ where
 		// we can't continue to relay finality if target node is out of sync, because
 		// it may have already received (some of) headers that we're going to relay
 		self.client.ensure_synced().await?;
+		// we can't relay finality if GRANDPA pallet at target chain is halted
+		self.ensure_pallet_active().await?;
 
 		Ok(crate::messages_source::read_client_state::<
 			P::TargetChain,

bridges/relays/lib-substrate-relay/src/messages_lane.rs

@@ -34,8 +34,8 @@ use frame_support::weights::{GetDispatchInfo, Weight};
 use messages_relay::{message_lane::MessageLane, relay_strategy::RelayStrategy};
 use pallet_bridge_messages::{Call as BridgeMessagesCall, Config as BridgeMessagesConfig};
 use relay_substrate_client::{
-	AccountKeyPairOf, BalanceOf, BlockNumberOf, CallOf, Chain, ChainWithMessages, Client, HashOf,
-	TransactionSignScheme,
+	transaction_stall_timeout, AccountKeyPairOf, BalanceOf, BlockNumberOf, CallOf, Chain,
+	ChainWithMessages, Client, HashOf, TransactionSignScheme,
 };
 use relay_utils::metrics::MetricsParams;
 use sp_core::Pair;
@@ -173,7 +173,7 @@ where
 			Max messages in single transaction: {}\n\t\
 			Max messages size in single transaction: {}\n\t\
 			Max messages weight in single transaction: {}\n\t\
-			Tx mortality: {:?}/{:?}\n\t\
+			Tx mortality: {:?} (~{}m)/{:?} (~{}m)\n\t\
 			Stall timeout: {:?}",
 		P::SourceChain::NAME,
 		P::TargetChain::NAME,
@@ -183,7 +183,17 @@ where
 		max_messages_size_in_single_batch,
 		max_messages_weight_in_single_batch,
 		params.source_transaction_params.mortality,
+		transaction_stall_timeout(
+			params.source_transaction_params.mortality,
+			P::SourceChain::AVERAGE_BLOCK_INTERVAL,
+			STALL_TIMEOUT,
+		).as_secs_f64() / 60.0f64,
 		params.target_transaction_params.mortality,
+		transaction_stall_timeout(
+			params.target_transaction_params.mortality,
+			P::TargetChain::AVERAGE_BLOCK_INTERVAL,
+			STALL_TIMEOUT,
+		).as_secs_f64() / 60.0f64,
 		stall_timeout,
 	);