XCM: Tools for uniquely referencing messages

Cargo.toml

@@ -210,6 +210,7 @@ runtime-metrics = [ "polkadot-cli/runtime-metrics" ]
 pyroscope = ["polkadot-cli/pyroscope"]
 jemalloc-allocator = ["polkadot-node-core-pvf-worker/jemalloc-allocator", "polkadot-overseer/jemalloc-allocator"]
 
+
 # Configuration for building a .deb package - for use with `cargo-deb`
 [package.metadata.deb]
 name = "polkadot"

runtime/kusama/src/xcm_config.rs

@@ -36,13 +36,13 @@ use runtime_common::{
 use sp_core::ConstU32;
 use xcm::latest::prelude::*;
 use xcm_builder::{
-	AccountId32Aliases, AllowExplicitUnpaidExecutionFrom, AllowKnownQueryResponses,
+	AccountId32Aliases, AllowExplicitUnpaidExecutionFrom, AllowKnownQueryResponses, AllowSetTopic,
 	AllowSubscriptionsFrom, AllowTopLevelPaidExecutionFrom, ChildParachainAsNative,
 	ChildParachainConvertsVia, ChildSystemParachainAsSuperuser,
 	CurrencyAdapter as XcmCurrencyAdapter, FixedWeightBounds, IsChildSystemParachain, IsConcrete,
 	MintLocation, OriginToPluralityVoice, SignedAccountId32AsNative, SignedToAccountId32,
 	SovereignSignedViaLocation, TakeWeightCredit, UsingComponents, WeightInfoBounds,
-	WithComputedOrigin,
+	WithComputedOrigin, WithUniqueTopic,
 };
 use xcm_executor::traits::WithOriginFilter;
 
@@ -115,14 +115,14 @@ parameter_types! {
 
 /// The XCM router. When we want to send an XCM message, we use this type. It amalgamates all of our
 /// individual routers.
-pub type XcmRouter = (
+pub type XcmRouter = WithUniqueTopic<(
 	// Only one router so far - use DMP to communicate with child parachains.
 	ChildParachainRouter<
 		Runtime,
 		XcmPallet,
 		ExponentialPrice<FeeAssetId, BaseDeliveryFee, TransactionByteFee, Dmp>,
 	>,
-);
+)>;
 
 parameter_types! {
 	pub const Ksm: MultiAssetFilter = Wild(AllOf { fun: WildFungible, id: Concrete(TokenLocation::get()) });
@@ -142,7 +142,7 @@ match_types! {
 }
 
 /// The barriers one of which must be passed for an XCM message to be executed.
-pub type Barrier = (
+pub type Barrier = AllowSetTopic<(
 	// Weight that is paid for may be consumed.
 	TakeWeightCredit,
 	// Expected responses are OK.
@@ -159,7 +159,7 @@ pub type Barrier = (
 		UniversalLocation,
 		ConstU32<8>,
 	>,
-);
+)>;
 
 /// A call filter for the XCM Transact instruction. This is a temporary measure until we properly
 /// account for proof size weights.

runtime/parachains/src/ump.rs

@@ -92,11 +92,6 @@ pub type OverweightIndex = u64;
 /// and will be forwarded to the XCM Executor.
 pub struct XcmSink<XcmExecutor, Config>(PhantomData<(XcmExecutor, Config)>);
 
-/// Returns a [`MessageId`] for the given upward message payload.
-fn upward_message_id(data: &[u8]) -> MessageId {
-	sp_io::hashing::blake2_256(data)
-}
-
 impl<XcmExecutor: xcm::latest::ExecuteXcm<C::RuntimeCall>, C: Config> UmpSink
 	for XcmSink<XcmExecutor, C>
 {
@@ -111,7 +106,8 @@ impl<XcmExecutor: xcm::latest::ExecuteXcm<C::RuntimeCall>, C: Config> UmpSink
 			VersionedXcm,
 		};
 
-		let id = upward_message_id(data);
+		// The fallback message id.
+		let hash = sp_io::hashing::blake2_256(data);
 		let maybe_msg_and_weight = VersionedXcm::<C::RuntimeCall>::decode_all_with_depth_limit(
 			xcm::MAX_XCM_DECODE_DEPTH,
 			&mut data,
@@ -128,16 +124,23 @@ impl<XcmExecutor: xcm::latest::ExecuteXcm<C::RuntimeCall>, C: Config> UmpSink
 		});
 		match maybe_msg_and_weight {
 			Err(_) => {
-				Pallet::<C>::deposit_event(Event::InvalidFormat(id));
+				Pallet::<C>::deposit_event(Event::InvalidFormat(hash));
 				Ok(Weight::zero())
 			},
 			Ok((Err(()), weight_used)) => {
-				Pallet::<C>::deposit_event(Event::UnsupportedVersion(id));
+				Pallet::<C>::deposit_event(Event::UnsupportedVersion(hash));
 				Ok(weight_used)
 			},
 			Ok((Ok(xcm_message), weight_used)) => {
 				let xcm_junction = Junction::Parachain(origin.into());
-				let outcome = XcmExecutor::execute_xcm(xcm_junction, xcm_message, id, max_weight);
+				let mut id = hash;
+				let outcome = XcmExecutor::prepare_and_execute(
+					xcm_junction,
+					xcm_message,
+					&mut id,
+					max_weight,
+					Weight::zero(),
+				);
 				match outcome {
 					Outcome::Error(XcmError::WeightLimitReached(required)) => Err((id, required)),
 					outcome => {

runtime/parachains/src/ump/benchmarking.rs

@@ -113,6 +113,7 @@ frame_benchmarking::benchmarks! {
 		// and take the decoding weight into account by adding it to the extrinsic execution weight
 		// in the process_upward_message function.
 		let msg = create_message_overweight::<T>();
+		let hash = msg.using_encoded(sp_io::hashing::blake2_256);
 
 		// This just makes sure that 0 is not a valid index and we can use it later on.
 		let _ = Ump::<T>::service_overweight(RawOrigin::Root.into(), 0, Weight::from_parts(1000, 1000));
@@ -122,8 +123,8 @@ frame_benchmarking::benchmarks! {
 		queue_upward_msg::<T>(&host_conf, para, msg.clone());
 		Ump::<T>::process_pending_upward_messages();
 		assert_last_event_type::<T>(
-			Event::OverweightEnqueued(para, upward_message_id(&msg), 0, Weight::zero()).into()
-			);
+			Event::OverweightEnqueued(para, hash, 0, Weight::zero()).into()
+		);
 	}: _(RawOrigin::Root, 0, Weight::MAX)
 	verify {
 		assert_last_event_type::<T>(Event::OverweightServiced(0, Weight::zero()).into());

runtime/parachains/src/ump/tests.rs

@@ -334,7 +334,7 @@ fn overweight_queue_works() {
 		assert_last_event(
 			Event::OverweightEnqueued(
 				para_a,
-				upward_message_id(&a_msg_3[..]),
+				sp_io::hashing::blake2_256(&a_msg_3[..]),
 				0,
 				Weight::from_parts(500, 500),
 			)

runtime/rococo/src/xcm_config.rs

@@ -35,12 +35,12 @@ use runtime_common::{
 use sp_core::ConstU32;
 use xcm::latest::prelude::*;
 use xcm_builder::{
-	AccountId32Aliases, AllowExplicitUnpaidExecutionFrom, AllowKnownQueryResponses,
+	AccountId32Aliases, AllowExplicitUnpaidExecutionFrom, AllowKnownQueryResponses, AllowSetTopic,
 	AllowSubscriptionsFrom, AllowTopLevelPaidExecutionFrom, BackingToPlurality,
 	ChildParachainAsNative, ChildParachainConvertsVia, ChildSystemParachainAsSuperuser,
 	CurrencyAdapter as XcmCurrencyAdapter, FixedWeightBounds, IsChildSystemParachain, IsConcrete,
 	MintLocation, SignedAccountId32AsNative, SignedToAccountId32, SovereignSignedViaLocation,
-	TakeWeightCredit, UsingComponents, WeightInfoBounds, WithComputedOrigin,
+	TakeWeightCredit, UsingComponents, WeightInfoBounds, WithComputedOrigin, WithUniqueTopic,
 };
 use xcm_executor::{traits::WithOriginFilter, XcmExecutor};
 
@@ -95,14 +95,14 @@ parameter_types! {
 
 /// The XCM router. When we want to send an XCM message, we use this type. It amalgamates all of our
 /// individual routers.
-pub type XcmRouter = (
+pub type XcmRouter = WithUniqueTopic<(
 	// Only one router so far - use DMP to communicate with child parachains.
 	ChildParachainRouter<
 		Runtime,
 		XcmPallet,
 		ExponentialPrice<FeeAssetId, BaseDeliveryFee, TransactionByteFee, Dmp>,
 	>,
-);
+)>;
 
 parameter_types! {
 	pub const Roc: MultiAssetFilter = Wild(AllOf { fun: WildFungible, id: Concrete(TokenLocation::get()) });
@@ -137,7 +137,7 @@ match_types! {
 }
 
 /// The barriers one of which must be passed for an XCM message to be executed.
-pub type Barrier = (
+pub type Barrier = AllowSetTopic<(
 	// Weight that is paid for may be consumed.
 	TakeWeightCredit,
 	// Expected responses are OK.
@@ -154,7 +154,7 @@ pub type Barrier = (
 		UniversalLocation,
 		ConstU32<8>,
 	>,
-);
+)>;
 
 /// A call filter for the XCM Transact instruction. This is a temporary measure until we
 /// properly account for proof size weights.

runtime/westend/src/xcm_config.rs

@@ -34,12 +34,12 @@ use sp_core::ConstU32;
 use westend_runtime_constants::currency::CENTS;
 use xcm::latest::prelude::*;
 use xcm_builder::{
-	AccountId32Aliases, AllowExplicitUnpaidExecutionFrom, AllowKnownQueryResponses,
+	AccountId32Aliases, AllowExplicitUnpaidExecutionFrom, AllowKnownQueryResponses, AllowSetTopic,
 	AllowSubscriptionsFrom, AllowTopLevelPaidExecutionFrom, ChildParachainAsNative,
 	ChildParachainConvertsVia, ChildSystemParachainAsSuperuser,
 	CurrencyAdapter as XcmCurrencyAdapter, IsChildSystemParachain, IsConcrete, MintLocation,
 	SignedAccountId32AsNative, SignedToAccountId32, SovereignSignedViaLocation, TakeWeightCredit,
-	UsingComponents, WeightInfoBounds, WithComputedOrigin,
+	UsingComponents, WeightInfoBounds, WithComputedOrigin, WithUniqueTopic,
 };
 use xcm_executor::{traits::WithOriginFilter, XcmExecutor};
 
@@ -80,14 +80,14 @@ type LocalOriginConverter = (
 
 /// The XCM router. When we want to send an XCM message, we use this type. It amalgamates all of our
 /// individual routers.
-pub type XcmRouter = (
+pub type XcmRouter = WithUniqueTopic<(
 	// Only one router so far - use DMP to communicate with child parachains.
 	ChildParachainRouter<
 		Runtime,
 		XcmPallet,
 		ExponentialPrice<FeeAssetId, BaseDeliveryFee, TransactionByteFee, Dmp>,
 	>,
-);
+)>;
 
 parameter_types! {
 	pub const Westmint: MultiLocation = Parachain(1000).into_location();
@@ -108,7 +108,7 @@ pub type TrustedTeleporters =
 	(xcm_builder::Case<WndForWestmint>, xcm_builder::Case<WndForCollectives>);
 
 /// The barriers one of which must be passed for an XCM message to be executed.
-pub type Barrier = (
+pub type Barrier = AllowSetTopic<(
 	// Weight that is paid for may be consumed.
 	TakeWeightCredit,
 	// Expected responses are OK.
@@ -125,7 +125,7 @@ pub type Barrier = (
 		UniversalLocation,
 		ConstU32<8>,
 	>,
-);
+)>;
 
 /// A call filter for the XCM Transact instruction. This is a temporary measure until we
 /// properly account for proof size weights.