xcm_config.rs

// Copyright (C) Parity Technologies (UK) Ltd.
// SPDX-License-Identifier: Apache-2.0

// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// 	http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

use super::{
	AccountId, AllPalletsWithSystem, Balances, ParachainInfo, ParachainSystem, PolkadotXcm,
	Runtime, RuntimeCall, RuntimeEvent, RuntimeOrigin, WeightToFee, XcmpQueue,
};
use frame_support::{
	match_types, parameter_types,
	traits::{ConstU32, EitherOfDiverse, Everything, Nothing},
	weights::Weight,
};
use frame_system::EnsureRoot;
use pallet_xcm::{EnsureXcm, IsMajorityOfBody, XcmPassthrough};
use polkadot_parachain_primitives::primitives::Sibling;
use xcm::latest::prelude::*;
use xcm_builder::{
	AccountId32Aliases, AllowExplicitUnpaidExecutionFrom, AllowKnownQueryResponses,
	AllowSubscriptionsFrom, AllowTopLevelPaidExecutionFrom, CurrencyAdapter,
	DenyReserveTransferToRelayChain, DenyThenTry, EnsureXcmOrigin, FixedWeightBounds, IsConcrete,
	NativeAsset, ParentAsSuperuser, ParentIsPreset, RelayChainAsNative, SiblingParachainAsNative,
	SiblingParachainConvertsVia, SignedAccountId32AsNative, SignedToAccountId32,
	SovereignSignedViaLocation, TakeWeightCredit, TrailingSetTopicAsId, UsingComponents,
	WithComputedOrigin, WithUniqueTopic,
};
use xcm_executor::XcmExecutor;

parameter_types! {
	pub const RelayLocation: MultiLocation = MultiLocation::parent();
	pub const RelayNetwork: Option<NetworkId> = None;
	pub RelayChainOrigin: RuntimeOrigin = cumulus_pallet_xcm::Origin::Relay.into();
	pub UniversalLocation: InteriorMultiLocation = Parachain(ParachainInfo::parachain_id().into()).into();
	pub const ExecutiveBody: BodyId = BodyId::Executive;
	pub CheckingAccount: AccountId = PolkadotXcm::check_account();
}

/// We allow root and the Relay Chain council to execute privileged collator selection operations.
pub type CollatorSelectionUpdateOrigin = EitherOfDiverse<
	EnsureRoot<AccountId>,
	EnsureXcm<IsMajorityOfBody<RelayLocation, ExecutiveBody>>,
>;

/// Type for specifying how a `MultiLocation` can be converted into an `AccountId`. This is used
/// when determining ownership of accounts for asset transacting and when attempting to use XCM
/// `Transact` in order to determine the dispatch Origin.
pub type LocationToAccountId = (
	// The parent (Relay-chain) origin converts to the parent `AccountId`.
	ParentIsPreset<AccountId>,
	// Sibling parachain origins convert to AccountId via the `ParaId::into`.
	SiblingParachainConvertsVia<Sibling, AccountId>,
	// Straight up local `AccountId32` origins just alias directly to `AccountId`.
	AccountId32Aliases<RelayNetwork, AccountId>,
);

/// Means for transacting the native currency on this chain.
pub type CurrencyTransactor = CurrencyAdapter<
	// Use this currency:
	Balances,
	// Use this currency when it is a fungible asset matching the given location or name:
	IsConcrete<RelayLocation>,
	// Convert an XCM MultiLocation into a local account id:
	LocationToAccountId,
	// Our chain's account ID type (we can't get away without mentioning it explicitly):
	AccountId,
	// We don't track any teleports of `Balances`.
	(),
>;

/// This is the type we use to convert an (incoming) XCM origin into a local `Origin` instance,
/// ready for dispatching a transaction with Xcm's `Transact`. There is an `OriginKind` which can
/// biases the kind of local `Origin` it will become.
pub type XcmOriginToTransactDispatchOrigin = (
	// Sovereign account converter; this attempts to derive an `AccountId` from the origin location
	// using `LocationToAccountId` and then turn that into the usual `Signed` origin. Useful for
	// foreign chains who want to have a local sovereign account on this chain which they control.
	SovereignSignedViaLocation<LocationToAccountId, RuntimeOrigin>,
	// Native converter for Relay-chain (Parent) location; will convert to a `Relay` origin when
	// recognised.
	RelayChainAsNative<RelayChainOrigin, RuntimeOrigin>,
	// Native converter for sibling Parachains; will convert to a `SiblingPara` origin when
	// recognised.
	SiblingParachainAsNative<cumulus_pallet_xcm::Origin, RuntimeOrigin>,
	// Superuser converter for the Relay-chain (Parent) location. This will allow it to issue a
	// transaction from the Root origin.
	ParentAsSuperuser<RuntimeOrigin>,
	// Native signed account converter; this just converts an `AccountId32` origin into a normal
	// `RuntimeOrigin::Signed` origin of the same 32-byte value.
	SignedAccountId32AsNative<RelayNetwork, RuntimeOrigin>,
	// Xcm origins can be represented natively under the Xcm pallet's Xcm origin.
	XcmPassthrough<RuntimeOrigin>,
);

parameter_types! {
	// One XCM operation is 1_000_000_000 weight - almost certainly a conservative estimate.
	pub UnitWeightCost: Weight = Weight::from_parts(1_000_000_000, 64 * 1024);
	pub const MaxInstructions: u32 = 100;
}

match_types! {
	pub type ParentOrParentsPlurality: impl Contains<MultiLocation> = {
		MultiLocation { parents: 1, interior: Here } |
		MultiLocation { parents: 1, interior: X1(Plurality { .. }) }
	};
	pub type ParentOrSiblings: impl Contains<MultiLocation> = {
		MultiLocation { parents: 1, interior: Here } |
		MultiLocation { parents: 1, interior: X1(_) }
	};
}

pub type Barrier = TrailingSetTopicAsId<
	DenyThenTry<
		DenyReserveTransferToRelayChain,
		(
			TakeWeightCredit,
			// Expected responses are OK.
			AllowKnownQueryResponses<PolkadotXcm>,
			// Allow XCMs with some computed origins to pass through.
			WithComputedOrigin<
				(
					// If the message is one that immediately attemps to pay for execution, then
					// allow it.
					AllowTopLevelPaidExecutionFrom<Everything>,
					// Parent and its pluralities (i.e. governance bodies) get free execution.
					AllowExplicitUnpaidExecutionFrom<ParentOrParentsPlurality>,
					// Subscriptions for version tracking are OK.
					AllowSubscriptionsFrom<ParentOrSiblings>,
				),
				UniversalLocation,
				ConstU32<8>,
			>,
		),
	>,
>;

pub struct XcmConfig;
impl xcm_executor::Config for XcmConfig {
	type RuntimeCall = RuntimeCall;
	type XcmSender = XcmRouter;
	type AssetTransactor = CurrencyTransactor;
	type OriginConverter = XcmOriginToTransactDispatchOrigin;
	type IsReserve = NativeAsset;
	type IsTeleporter = NativeAsset;
	type UniversalLocation = UniversalLocation;
	type Barrier = Barrier;
	type Weigher = FixedWeightBounds<UnitWeightCost, RuntimeCall, MaxInstructions>;
	type Trader = UsingComponents<WeightToFee, RelayLocation, AccountId, Balances, ()>;
	type ResponseHandler = PolkadotXcm;
	type AssetTrap = PolkadotXcm;
	type AssetClaims = PolkadotXcm;
	type SubscriptionService = PolkadotXcm;
	type PalletInstancesInfo = AllPalletsWithSystem;
	type MaxAssetsIntoHolding = ConstU32<8>;
	type AssetLocker = ();
	type AssetExchanger = ();
	type FeeManager = ();
	type MessageExporter = ();
	type UniversalAliases = Nothing;
	type CallDispatcher = RuntimeCall;
	type SafeCallFilter = Everything;
	type Aliasers = Nothing;
}

/// Converts a local signed origin into an XCM multilocation.
/// Forms the basis for local origins sending/executing XCMs.
pub type LocalOriginToLocation = SignedToAccountId32<RuntimeOrigin, AccountId, RelayNetwork>;

/// The means for routing XCM messages which are not for local execution into the right message
/// queues.
pub type XcmRouter = WithUniqueTopic<(
	// Two routers - use UMP to communicate with the relay chain:
	cumulus_primitives_utility::ParentAsUmp<ParachainSystem, PolkadotXcm, ()>,
	// ..and XCMP to communicate with the sibling chains.
	XcmpQueue,
)>;

#[cfg(feature = "runtime-benchmarks")]
parameter_types! {
	pub ReachableDest: Option<MultiLocation> = Some(Parent.into());
}

impl pallet_xcm::Config for Runtime {
	type RuntimeEvent = RuntimeEvent;
	// We want to disallow users sending (arbitrary) XCMs from this chain.
	type SendXcmOrigin = EnsureXcmOrigin<RuntimeOrigin, ()>;
	type XcmRouter = XcmRouter;
	// We support local origins dispatching XCM executions in principle...
	type ExecuteXcmOrigin = EnsureXcmOrigin<RuntimeOrigin, LocalOriginToLocation>;
	// ... but disallow generic XCM execution. As a result only teleports and reserve transfers are
	// allowed.
	type XcmExecuteFilter = Nothing;
	type XcmExecutor = XcmExecutor<XcmConfig>;
	type XcmTeleportFilter = Everything;
	type XcmReserveTransferFilter = Everything;
	type Weigher = FixedWeightBounds<UnitWeightCost, RuntimeCall, MaxInstructions>;
	type UniversalLocation = UniversalLocation;
	type RuntimeOrigin = RuntimeOrigin;
	type RuntimeCall = RuntimeCall;
	const VERSION_DISCOVERY_QUEUE_SIZE: u32 = 100;
	type AdvertisedXcmVersion = pallet_xcm::CurrentXcmVersion;
	type Currency = Balances;
	type CurrencyMatcher = ();
	type TrustedLockers = ();
	type SovereignAccountOf = LocationToAccountId;
	type MaxLockers = ConstU32<8>;
	// FIXME: Replace with benchmarked weight info
	type WeightInfo = pallet_xcm::TestWeightInfo;
	#[cfg(feature = "runtime-benchmarks")]
	type ReachableDest = ReachableDest;
	type AdminOrigin = EnsureRoot<AccountId>;
	type MaxRemoteLockConsumers = ConstU32<0>;
	type RemoteLockConsumerIdentifier = ();
}

impl cumulus_pallet_xcm::Config for Runtime {
	type RuntimeEvent = RuntimeEvent;
	type XcmExecutor = XcmExecutor<XcmConfig>;
}

impl cumulus_pallet_xcmp_queue::Config for Runtime {
	type RuntimeEvent = RuntimeEvent;
	type XcmExecutor = XcmExecutor<XcmConfig>;
	type ChannelInfo = ParachainSystem;
	type VersionWrapper = PolkadotXcm;
	type ExecuteOverweightOrigin = EnsureRoot<AccountId>;
	type ControllerOrigin = EitherOfDiverse<
		EnsureRoot<AccountId>,
		EnsureXcm<IsMajorityOfBody<RelayLocation, ExecutiveBody>>,
	>;
	type ControllerOriginConverter = XcmOriginToTransactDispatchOrigin;
	type WeightInfo = cumulus_pallet_xcmp_queue::weights::SubstrateWeight<Runtime>;
	type PriceForSiblingDelivery = ();
}

impl cumulus_pallet_dmp_queue::Config for Runtime {
	type RuntimeEvent = RuntimeEvent;
	type XcmExecutor = XcmExecutor<XcmConfig>;
	type ExecuteOverweightOrigin = EnsureRoot<AccountId>;
}