Allow Queries and Subscriptions (#700)

* Allow Queries and Subscriptions

* Fixes

* Formatting

cumulus/parachain-template/runtime/src/lib.rs

@@ -49,11 +49,11 @@ use polkadot_runtime_common::{BlockHashCount, RocksDbWeight, SlowAdjustingFeeUpd
 // XCM Imports
 use xcm::latest::prelude::*;
 use xcm_builder::{
-	AccountId32Aliases, AllowTopLevelPaidExecutionFrom, AllowUnpaidExecutionFrom, CurrencyAdapter,
+	AccountId32Aliases, AllowKnownQueryResponses, AllowSubscriptionsFrom,
-	EnsureXcmOrigin, FixedWeightBounds, IsConcrete, LocationInverter, NativeAsset,
+	AllowTopLevelPaidExecutionFrom, AllowUnpaidExecutionFrom, CurrencyAdapter, EnsureXcmOrigin,
-	ParentAsSuperuser, ParentIsDefault, RelayChainAsNative, SiblingParachainAsNative,
+	FixedWeightBounds, IsConcrete, LocationInverter, NativeAsset, ParentAsSuperuser,
-	SiblingParachainConvertsVia, SignedAccountId32AsNative, SovereignSignedViaLocation,
+	ParentIsDefault, RelayChainAsNative, SiblingParachainAsNative, SiblingParachainConvertsVia,
-	TakeWeightCredit, UsingComponents,
+	SignedAccountId32AsNative, SovereignSignedViaLocation, TakeWeightCredit, UsingComponents,
 };
 use xcm_executor::{Config, XcmExecutor};
 
@@ -465,12 +465,22 @@ match_type! {
 		MultiLocation { parents: 1, interior: X1(Plurality { id: BodyId::Executive, .. }) }
 	};
 }
+match_type! {
+	pub type ParentOrSiblings: impl Contains<MultiLocation> = {
+		MultiLocation { parents: 1, interior: Here } |
+		MultiLocation { parents: 1, interior: X1(_) }
+	};
+}
 
 pub type Barrier = (
 	TakeWeightCredit,
 	AllowTopLevelPaidExecutionFrom<Everything>,
 	AllowUnpaidExecutionFrom<ParentOrParentsExecutivePlurality>,
 	// ^^^ Parent and its exec plurality get free execution
+	// Expected responses are OK.
+	AllowKnownQueryResponses<PolkadotXcm>,
+	// Subscriptions for version tracking are OK.
+	AllowSubscriptionsFrom<ParentOrSiblings>,
 );
 
 pub struct XcmConfig;

cumulus/polkadot-parachains/rococo/src/lib.rs

@@ -60,7 +60,10 @@ use parachains_common::{
 	impls::{AssetsFrom, NonZeroIssuance},
 	AssetId,
 };
-use xcm_builder::{AsPrefixedGeneralIndex, ConvertedConcreteAssetId, FungiblesAdapter};
+use xcm_builder::{
+	AllowKnownQueryResponses, AllowSubscriptionsFrom, AsPrefixedGeneralIndex,
+	ConvertedConcreteAssetId, FungiblesAdapter,
+};
 use xcm_executor::traits::JustTry;
 
 // XCM imports
@@ -376,6 +379,10 @@ pub type Barrier = (
 	AllowUnpaidExecutionFrom<ParentOrParentsUnitPlurality>,
 	// ^^^ Parent & its unit plurality gets free execution
 	AllowUnpaidExecutionFrom<Statemint>,
+	// Expected responses are OK.
+	AllowKnownQueryResponses<PolkadotXcm>,
+	// Subscriptions for version tracking are OK.
+	AllowSubscriptionsFrom<Everything>,
 );
 
 parameter_types! {

cumulus/polkadot-parachains/statemine/src/lib.rs

@@ -70,12 +70,12 @@ use polkadot_parachain::primitives::Sibling;
 use polkadot_runtime_common::{BlockHashCount, RocksDbWeight, SlowAdjustingFeeUpdate};
 use xcm::latest::prelude::*;
 use xcm_builder::{
-	AccountId32Aliases, AllowTopLevelPaidExecutionFrom, AllowUnpaidExecutionFrom,
+	AccountId32Aliases, AllowKnownQueryResponses, AllowSubscriptionsFrom,
-	AsPrefixedGeneralIndex, ConvertedConcreteAssetId, CurrencyAdapter, EnsureXcmOrigin,
+	AllowTopLevelPaidExecutionFrom, AllowUnpaidExecutionFrom, AsPrefixedGeneralIndex,
-	FixedWeightBounds, FungiblesAdapter, IsConcrete, LocationInverter, NativeAsset,
+	ConvertedConcreteAssetId, CurrencyAdapter, EnsureXcmOrigin, FixedWeightBounds,
-	ParentAsSuperuser, ParentIsDefault, RelayChainAsNative, SiblingParachainAsNative,
+	FungiblesAdapter, IsConcrete, LocationInverter, NativeAsset, ParentAsSuperuser,
-	SiblingParachainConvertsVia, SignedAccountId32AsNative, SovereignSignedViaLocation,
+	ParentIsDefault, RelayChainAsNative, SiblingParachainAsNative, SiblingParachainConvertsVia,
-	TakeWeightCredit, UsingComponents,
+	SignedAccountId32AsNative, SovereignSignedViaLocation, TakeWeightCredit, UsingComponents,
 };
 use xcm_executor::{traits::JustTry, Config, XcmExecutor};
 
@@ -557,12 +557,22 @@ match_type! {
 		MultiLocation { parents: 1, interior: X1(Plurality { id: BodyId::Executive, .. }) }
 	};
 }
+match_type! {
+	pub type ParentOrSiblings: impl Contains<MultiLocation> = {
+		MultiLocation { parents: 1, interior: Here } |
+		MultiLocation { parents: 1, interior: X1(_) }
+	};
+}
 
 pub type Barrier = (
 	TakeWeightCredit,
 	AllowTopLevelPaidExecutionFrom<Everything>,
 	AllowUnpaidExecutionFrom<ParentOrParentsExecutivePlurality>,
 	// ^^^ Parent and its exec plurality get free execution
+	// Expected responses are OK.
+	AllowKnownQueryResponses<PolkadotXcm>,
+	// Subscriptions for version tracking are OK.
+	AllowSubscriptionsFrom<ParentOrSiblings>,
 );
 
 pub struct XcmConfig;

cumulus/polkadot-parachains/statemint/src/lib.rs

@@ -70,12 +70,12 @@ use polkadot_parachain::primitives::Sibling;
 use polkadot_runtime_common::{BlockHashCount, RocksDbWeight, SlowAdjustingFeeUpdate};
 use xcm::latest::prelude::*;
 use xcm_builder::{
-	AccountId32Aliases, AllowTopLevelPaidExecutionFrom, AllowUnpaidExecutionFrom,
+	AccountId32Aliases, AllowKnownQueryResponses, AllowSubscriptionsFrom,
-	AsPrefixedGeneralIndex, ConvertedConcreteAssetId, CurrencyAdapter, EnsureXcmOrigin,
+	AllowTopLevelPaidExecutionFrom, AllowUnpaidExecutionFrom, AsPrefixedGeneralIndex,
-	FixedWeightBounds, FungiblesAdapter, IsConcrete, LocationInverter, NativeAsset,
+	ConvertedConcreteAssetId, CurrencyAdapter, EnsureXcmOrigin, FixedWeightBounds,
-	ParentAsSuperuser, ParentIsDefault, RelayChainAsNative, SiblingParachainAsNative,
+	FungiblesAdapter, IsConcrete, LocationInverter, NativeAsset, ParentAsSuperuser,
-	SiblingParachainConvertsVia, SignedAccountId32AsNative, SovereignSignedViaLocation,
+	ParentIsDefault, RelayChainAsNative, SiblingParachainAsNative, SiblingParachainConvertsVia,
-	TakeWeightCredit, UsingComponents,
+	SignedAccountId32AsNative, SovereignSignedViaLocation, TakeWeightCredit, UsingComponents,
 };
 use xcm_executor::{traits::JustTry, Config, XcmExecutor};
 
@@ -534,12 +534,22 @@ match_type! {
 		MultiLocation { parents: 1, interior: X1(Plurality { id: BodyId::Executive, .. }) }
 	};
 }
+match_type! {
+	pub type ParentOrSiblings: impl Contains<MultiLocation> = {
+		MultiLocation { parents: 1, interior: Here } |
+		MultiLocation { parents: 1, interior: X1(_) }
+	};
+}
 
 pub type Barrier = (
 	TakeWeightCredit,
 	AllowTopLevelPaidExecutionFrom<Everything>,
 	AllowUnpaidExecutionFrom<ParentOrParentsExecutivePlurality>,
 	// ^^^ Parent and its exec plurality get free execution
+	// Expected responses are OK.
+	AllowKnownQueryResponses<PolkadotXcm>,
+	// Subscriptions for version tracking are OK.
+	AllowSubscriptionsFrom<ParentOrSiblings>,
 );
 
 pub struct XcmConfig;

cumulus/polkadot-parachains/westmint/src/lib.rs

@@ -70,12 +70,13 @@ use polkadot_parachain::primitives::Sibling;
 use polkadot_runtime_common::{BlockHashCount, RocksDbWeight, SlowAdjustingFeeUpdate};
 use xcm::latest::prelude::*;
 use xcm_builder::{
-	AccountId32Aliases, AllowTopLevelPaidExecutionFrom, AllowUnpaidExecutionFrom,
+	AccountId32Aliases, AllowKnownQueryResponses, AllowSubscriptionsFrom,
-	AsPrefixedGeneralIndex, ConvertedConcreteAssetId, CurrencyAdapter, EnsureXcmOrigin,
+	AllowTopLevelPaidExecutionFrom, AllowUnpaidExecutionFrom, AsPrefixedGeneralIndex,
-	FixedWeightBounds, FungiblesAdapter, IsConcrete, LocationInverter, NativeAsset,
+	ConvertedConcreteAssetId, CurrencyAdapter, EnsureXcmOrigin, FixedWeightBounds,
-	ParentAsSuperuser, ParentIsDefault, RelayChainAsNative, SiblingParachainAsNative,
+	FungiblesAdapter, IsConcrete, LocationInverter, NativeAsset, ParentAsSuperuser,
-	SiblingParachainConvertsVia, SignedAccountId32AsNative, SignedToAccountId32,
+	ParentIsDefault, RelayChainAsNative, SiblingParachainAsNative, SiblingParachainConvertsVia,
-	SovereignSignedViaLocation, TakeWeightCredit, UsingComponents,
+	SignedAccountId32AsNative, SignedToAccountId32, SovereignSignedViaLocation, TakeWeightCredit,
+	UsingComponents,
 };
 use xcm_executor::{traits::JustTry, Config, XcmExecutor};
 
@@ -526,6 +527,10 @@ pub type Barrier = (
 	AllowTopLevelPaidExecutionFrom<Everything>,
 	AllowUnpaidExecutionFrom<ParentOrParentsPlurality>,
 	// ^^^ Parent & its plurality gets free execution
+	// Expected responses are OK.
+	AllowKnownQueryResponses<PolkadotXcm>,
+	// Subscriptions for version tracking are OK.
+	AllowSubscriptionsFrom<Everything>,
 );
 
 pub struct XcmConfig;