Fee paid on BH

bridges/snowbridge/pallets/inbound-queue/src/lib.rs

@@ -290,8 +290,8 @@ pub mod pallet {
 			let _ = match message {
 				VersionedMessage::V1(MessageV1 {
 					command: Command::RewardRelay { message_id, relay_address },
-					..
-				}) => T::Payer::reward_relay(message_id, relay_address)
+					chain_id,
+				}) => T::Payer::reward_relay(chain_id, message_id, relay_address)
 					.map_err(|e| Error::<T>::PayReward(e)),
 				_ => Ok(()),
 			}?;

bridges/snowbridge/pallets/outbound-queue/Cargo.toml

@@ -33,44 +33,52 @@ bridge-hub-common = { path = "../../../../cumulus/parachains/runtimes/bridge-hub
 snowbridge-core = { path = "../../primitives/core", default-features = false, features = ["serde"] }
 snowbridge-outbound-queue-merkle-tree = { path = "merkle-tree", default-features = false }
 ethabi = { package = "ethabi-decode", version = "1.0.0", default-features = false }
+xcm = { package = "staging-xcm", path = "../../../../polkadot/xcm", default-features = false }
+xcm-executor = { package = "staging-xcm-executor", path = "../../../../polkadot/xcm/xcm-executor", default-features = false }
 
 [dev-dependencies]
 pallet-message-queue = { path = "../../../../substrate/frame/message-queue", default-features = false }
 sp-keyring = { path = "../../../../substrate/primitives/keyring" }
+pallet-balances = { path = "../../../../substrate/frame/balances" }
 
 [features]
 default = ["std"]
 std = [
-	"bridge-hub-common/std",
-	"codec/std",
-	"ethabi/std",
-	"frame-benchmarking/std",
-	"frame-support/std",
-	"frame-system/std",
-	"pallet-message-queue/std",
-	"scale-info/std",
-	"serde/std",
-	"snowbridge-core/std",
-	"snowbridge-outbound-queue-merkle-tree/std",
-	"sp-arithmetic/std",
-	"sp-core/std",
-	"sp-io/std",
-	"sp-runtime/std",
-	"sp-std/std",
+    "bridge-hub-common/std",
+    "codec/std",
+    "ethabi/std",
+    "frame-benchmarking/std",
+    "frame-support/std",
+    "frame-system/std",
+    "pallet-message-queue/std",
+    "scale-info/std",
+    "serde/std",
+    "snowbridge-core/std",
+    "snowbridge-outbound-queue-merkle-tree/std",
+    "sp-arithmetic/std",
+    "sp-core/std",
+    "sp-io/std",
+    "sp-runtime/std",
+    "sp-std/std",
+    "xcm-executor/std",
+    "xcm/std",
 ]
 runtime-benchmarks = [
-	"bridge-hub-common/runtime-benchmarks",
-	"frame-benchmarking",
-	"frame-benchmarking/runtime-benchmarks",
-	"frame-support/runtime-benchmarks",
-	"frame-system/runtime-benchmarks",
-	"pallet-message-queue/runtime-benchmarks",
-	"snowbridge-core/runtime-benchmarks",
-	"sp-runtime/runtime-benchmarks",
+    "bridge-hub-common/runtime-benchmarks",
+    "frame-benchmarking",
+    "frame-benchmarking/runtime-benchmarks",
+    "frame-support/runtime-benchmarks",
+    "frame-system/runtime-benchmarks",
+    "pallet-balances/runtime-benchmarks",
+    "pallet-message-queue/runtime-benchmarks",
+    "snowbridge-core/runtime-benchmarks",
+    "sp-runtime/runtime-benchmarks",
+    "xcm-executor/runtime-benchmarks",
 ]
 try-runtime = [
-	"frame-support/try-runtime",
-	"frame-system/try-runtime",
-	"pallet-message-queue/try-runtime",
-	"sp-runtime/try-runtime",
+    "frame-support/try-runtime",
+    "frame-system/try-runtime",
+    "pallet-balances/try-runtime",
+    "pallet-message-queue/try-runtime",
+    "sp-runtime/try-runtime",
 ]

bridges/snowbridge/pallets/outbound-queue/src/lib.rs

@@ -107,9 +107,13 @@ use bridge_hub_common::{AggregateMessageOrigin, CustomDigestItem};
 use codec::Decode;
 use frame_support::{
 	storage::StorageStreamIter,
-	traits::{tokens::Balance, Contains, Defensive, EnqueueMessage, Get, ProcessMessageError},
+	traits::{
+		fungible::Inspect, tokens::Balance, Contains, Defensive, EnqueueMessage, Get,
+		ProcessMessageError,
+	},
 	weights::{Weight, WeightToFee},
 };
+pub use pallet::*;
 use snowbridge_core::{
 	outbound::{Fee, GasMeter, QueuedMessage, VersionedQueuedMessage, ETHER_DECIMALS},
 	BasicOperatingMode, ChannelId,
@@ -124,16 +128,22 @@ use sp_runtime::{
 use sp_std::prelude::*;
 pub use types::{CommittedMessage, ProcessMessageOriginOf};
 pub use weights::WeightInfo;
+use xcm::prelude::{Junction::*, Location, NetworkId};
+use xcm_executor::traits::ConvertLocation;
 
-pub use pallet::*;
+type BalanceOf<T> =
+	<<T as pallet::Config>::Token as Inspect<<T as frame_system::Config>::AccountId>>::Balance;
 
 #[frame_support::pallet]
 pub mod pallet {
 	use super::*;
-	use frame_support::pallet_prelude::*;
+	use frame_support::{
+		pallet_prelude::*,
+		traits::fungible::{Inspect, Mutate},
+	};
 	use frame_system::pallet_prelude::*;
-	use snowbridge_core::PricingParameters;
-	use sp_arithmetic::FixedU128;
+	use snowbridge_core::{PayRewardError, PricingParameters};
+	use sp_arithmetic::{traits::SaturatedConversion, FixedU128};
 
 	#[pallet::pallet]
 	pub struct Pallet<T>(_);
@@ -173,6 +183,9 @@ pub mod pallet {
 
 		/// Weight information for extrinsics in this pallet
 		type WeightInfo: WeightInfo;
+
+		/// Message relayers are rewarded with this asset
+		type Token: Mutate<Self::AccountId> + Inspect<Self::AccountId>;
 	}
 
 	#[pallet::event]
@@ -437,11 +450,27 @@ pub mod pallet {
 			Ok(())
 		}
 
-		pub(crate) fn unlock_fee(message_id: H256, _relay: H160) -> DispatchResult {
-			let _fee = <LockedFee<T>>::get(message_id);
-			// Todo: mint fee to the sovereign of the beneficiary
-			// let sovereign: AccountId = sovereign_of(_relay);
-			// T::Token::mint_into(sovereign,_fee);
+		pub(crate) fn unlock_fee(
+			chain_id: u64,
+			message_id: H256,
+			relay: H160,
+		) -> Result<(), PayRewardError>
+		where
+			<T as frame_system::Config>::AccountId: From<[u8; 32]>,
+		{
+			let fee: BalanceOf<T> = <LockedFee<T>>::get(message_id).saturated_into();
+
+			let account = snowbridge_core::SovereignIdOf::convert_location(&Location::new(
+				2,
+				[
+					GlobalConsensus(NetworkId::Ethereum { chain_id }),
+					AccountKey20 { network: None, key: relay.into() },
+				],
+			))
+			.ok_or(PayRewardError::AccountIdConversionFailed)?;
+			let sovereign_account: T::AccountId = account.into();
+
+			T::Token::mint_into(&sovereign_account, fee).map_err(|_| PayRewardError::CantMint)?;
 			<LockedFee<T>>::remove(message_id);
 			Ok(())
 		}

bridges/snowbridge/pallets/outbound-queue/src/mock.rs

@@ -16,23 +16,26 @@ use snowbridge_core::{
 };
 use sp_core::{ConstU32, ConstU8, H160, H256};
 use sp_runtime::{
-	traits::{BlakeTwo256, IdentityLookup, Keccak256},
-	AccountId32, BuildStorage, FixedU128,
+	traits::{BlakeTwo256, IdentifyAccount, IdentityLookup, Keccak256, Verify},
+	BuildStorage, FixedU128, MultiSignature,
 };
 use sp_std::marker::PhantomData;
 
 type Block = frame_system::mocking::MockBlock<Test>;
-type AccountId = AccountId32;
 
 frame_support::construct_runtime!(
 	pub enum Test
 	{
 		System: frame_system::{Pallet, Call, Storage, Event<T>},
+		Balances: pallet_balances::{Pallet, Call, Storage, Config<T>, Event<T>},
 		MessageQueue: pallet_message_queue::{Pallet, Call, Storage, Event<T>},
 		OutboundQueue: crate::{Pallet, Storage, Event<T>},
 	}
 );
 
+pub type Signature = MultiSignature;
+pub type AccountId = <<Signature as Verify>::Signer as IdentifyAccount>::AccountId;
+
 #[derive_impl(frame_system::config_preludes::TestDefaultConfig)]
 impl frame_system::Config for Test {
 	type BaseCallFilter = Everything;
@@ -45,10 +48,30 @@ impl frame_system::Config for Test {
 	type Lookup = IdentityLookup<Self::AccountId>;
 	type RuntimeEvent = RuntimeEvent;
 	type PalletInfo = PalletInfo;
+	type AccountData = pallet_balances::AccountData<u128>;
 	type Nonce = u64;
 	type Block = Block;
 }
 
+parameter_types! {
+	pub const ExistentialDeposit: u128 = 1;
+}
+impl pallet_balances::Config for Test {
+	type MaxLocks = ();
+	type MaxReserves = ();
+	type ReserveIdentifier = [u8; 8];
+	type Balance = u128;
+	type RuntimeEvent = RuntimeEvent;
+	type DustRemoval = ();
+	type ExistentialDeposit = ExistentialDeposit;
+	type AccountStore = System;
+	type WeightInfo = ();
+	type FreezeIdentifier = ();
+	type MaxFreezes = ();
+	type RuntimeHoldReason = ();
+	type RuntimeFreezeReason = ();
+}
+
 parameter_types! {
 	pub const HeapSize: u32 = 32 * 1024;
 	pub const MaxStale: u32 = 32;
@@ -93,6 +116,7 @@ impl crate::Config for Test {
 	type Channels = Everything;
 	type WeightToFee = IdentityFee<u128>;
 	type WeightInfo = ();
+	type Token = Balances;
 }
 
 fn setup() {

bridges/snowbridge/pallets/outbound-queue/src/send_message_impl.rs

@@ -119,9 +119,12 @@ impl<T: Config> SendMessageFeeProvider for Pallet<T> {
 	}
 }
 
-impl<T: Config> PayMaster for Pallet<T> {
+impl<T: Config> PayMaster for Pallet<T>
+where
+	<T as frame_system::Config>::AccountId: From<[u8; 32]>,
+{
 	/// The local component of the message processing fees in native currency
-	fn reward_relay(message_id: H256, relay: H160) -> Result<(), PayRewardError> {
-		Self::unlock_fee(message_id, relay).map_err(|_| PayRewardError::Other)
+	fn reward_relay(chain_id: u64, message_id: H256, relay: H160) -> Result<(), PayRewardError> {
+		Self::unlock_fee(chain_id, message_id, relay)
 	}
 }

bridges/snowbridge/primitives/core/src/lib.rs

@@ -168,16 +168,20 @@ pub type AgentIdOf = HashedDescription<H256, (DescribeHere, DescribeFamily<Descr
 #[derive(Clone, Encode, Decode, RuntimeDebug, PalletError, TypeInfo)]
 #[cfg_attr(feature = "std", derive(PartialEq))]
 pub enum PayRewardError {
+	AccountIdConversionFailed,
 	CantMint,
 	Other,
 }
 
 pub trait PayMaster {
-	fn reward_relay(message_id: H256, relay: H160) -> Result<(), PayRewardError>;
+	fn reward_relay(chain_id: u64, message_id: H256, relay: H160) -> Result<(), PayRewardError>;
 }
 
 impl PayMaster for () {
-	fn reward_relay(_: H256, _: H160) -> Result<(), PayRewardError> {
+	fn reward_relay(_: u64, _: H256, _: H160) -> Result<(), PayRewardError> {
 		Ok(())
 	}
 }
+
+pub type SovereignIdOf =
+	HashedDescription<[u8; 32], (DescribeHere, DescribeFamily<DescribeAllTerminal>)>;

cumulus/parachains/runtimes/bridge-hubs/bridge-hub-rococo/src/bridge_to_ethereum_config.rs

@@ -106,6 +106,7 @@ impl snowbridge_pallet_outbound_queue::Config for Runtime {
 	type WeightInfo = crate::weights::snowbridge_pallet_outbound_queue::WeightInfo<Runtime>;
 	type PricingParameters = EthereumSystem;
 	type Channels = EthereumSystem;
+	type Token = Balances;
 }
 
 #[cfg(any(feature = "std", feature = "fast-runtime", feature = "runtime-benchmarks", test))]

cumulus/parachains/runtimes/bridge-hubs/bridge-hub-westend/src/bridge_to_ethereum_config.rs

@@ -108,6 +108,7 @@ impl snowbridge_pallet_outbound_queue::Config for Runtime {
 	type WeightInfo = crate::weights::snowbridge_pallet_outbound_queue::WeightInfo<Runtime>;
 	type PricingParameters = EthereumSystem;
 	type Channels = EthereumSystem;
+	type Token = Balances;
 }
 
 #[cfg(any(feature = "std", feature = "fast-runtime", feature = "runtime-benchmarks", test))]