Xcm in Rialto<>Millau bridge (paritytech#1379)

* add XCM pallet to Millau runtime

* some progress

* messages are delivered (no fee)

* temp

* flush

* flush

* some progress

* progress

* Trap(42) is dispatched successfully

* fix spelling

* no more manual sending

* parametrize weight credit for tests

* actually charge fees

* enable send-using-messages-pallet to keep our test deployments alive + send valid XCM sometimes

* fix benchmarks build

* fix tests

bridges/bin/millau/node/src/chain_spec.rs

@@ -217,6 +217,7 @@ fn testnet_genesis(
 			owner: Some(get_account_id_from_seed::<sr25519::Public>("RialtoMessagesOwner")),
 			..Default::default()
 		},
+		xcm_pallet: Default::default(),
 	}
 }
 

bridges/bin/millau/runtime/Cargo.toml

@@ -11,6 +11,7 @@ license = "GPL-3.0-or-later WITH Classpath-exception-2.0"
 hex-literal = "0.3"
 codec = { package = "parity-scale-codec", version = "3.0.0", default-features = false, features = ["derive"] }
 libsecp256k1 = { version = "0.7", optional = true, default-features = false, features = ["hmac"] }
+log = { version = "0.4.14", default-features = false }
 scale-info = { version = "2.1.1", default-features = false, features = ["derive"] }
 serde = { version = "1.0", optional = true, features = ["derive"] }
 
@@ -53,6 +54,7 @@ sp-consensus-aura = { git = "https://github.com/paritytech/substrate", branch =
 sp-core = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 sp-finality-grandpa = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 sp-inherents = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
+sp-io = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 sp-mmr-primitives = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 sp-offchain = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 sp-runtime = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
@@ -62,8 +64,16 @@ sp-transaction-pool = { git = "https://github.com/paritytech/substrate", branch
 sp-trie = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 sp-version = { git = "https://github.com/paritytech/substrate", branch = "master", default-features = false }
 
+# Polkadot Dependencies
+
+pallet-xcm = { git = "https://github.com/paritytech/polkadot", branch = "gav-xcm-v3", default-features = false }
+xcm = { git = "https://github.com/paritytech/polkadot", branch = "gav-xcm-v3", default-features = false }
+xcm-builder = { git = "https://github.com/paritytech/polkadot", branch = "gav-xcm-v3", default-features = false }
+xcm-executor = { git = "https://github.com/paritytech/polkadot", branch = "gav-xcm-v3", default-features = false }
+
 [dev-dependencies]
 bridge-runtime-common = { path = "../../runtime-common", features = ["integrity-test"] }
+env_logger = "0.8"
 static_assertions = "1.1"
 
 [build-dependencies]
@@ -85,6 +95,7 @@ std = [
 	"frame-support/std",
 	"frame-system-rpc-runtime-api/std",
 	"frame-system/std",
+	"log/std",
 	"pallet-aura/std",
 	"pallet-balances/std",
 	"pallet-beefy/std",
@@ -100,6 +111,7 @@ std = [
 	"pallet-timestamp/std",
 	"pallet-transaction-payment-rpc-runtime-api/std",
 	"pallet-transaction-payment/std",
+	"pallet-xcm/std",
 	"scale-info/std",
 	"serde",
 	"sp-api/std",
@@ -108,13 +120,17 @@ std = [
 	"sp-core/std",
 	"sp-finality-grandpa/std",
 	"sp-inherents/std",
+	"sp-io/std",
 	"sp-offchain/std",
 	"sp-runtime/std",
 	"sp-session/std",
 	"sp-std/std",
 	"sp-transaction-pool/std",
 	"sp-trie/std",
 	"sp-version/std",
+	"xcm/std",
+	"xcm-builder/std",
+	"xcm-executor/std",
 ]
 runtime-benchmarks = [
 	"bridge-runtime-common/runtime-benchmarks",
@@ -123,5 +139,7 @@ runtime-benchmarks = [
 	"frame-system/runtime-benchmarks",
 	"libsecp256k1",
 	"pallet-bridge-messages/runtime-benchmarks",
+	"pallet-xcm/runtime-benchmarks",
 	"sp-runtime/runtime-benchmarks",
+	"xcm-builder/runtime-benchmarks",
 ]

bridges/bin/millau/runtime/src/lib.rs

@@ -29,6 +29,7 @@
 include!(concat!(env!("OUT_DIR"), "/wasm_binary.rs"));
 
 pub mod rialto_messages;
+pub mod xcm_config;
 
 use crate::rialto_messages::{ToRialtoMessagePayload, WithRialtoMessageBridge};
 
@@ -451,13 +452,7 @@ impl pallet_bridge_messages::Config<WithRialtoMessagesInstance> for Runtime {
 
 	type TargetHeaderChain = crate::rialto_messages::Rialto;
 	type LaneMessageVerifier = crate::rialto_messages::ToRialtoMessageVerifier;
-	type MessageDeliveryAndDispatchPayment =
-		pallet_bridge_messages::instant_payments::InstantCurrencyPayments<
-			Runtime,
-			WithRialtoMessagesInstance,
-			pallet_balances::Pallet<Runtime>,
-			GetDeliveryConfirmationTransactionFee,
-		>;
+	type MessageDeliveryAndDispatchPayment = ();
 	type OnMessageAccepted = ();
 	type OnDeliveryConfirmed = ();
 
@@ -499,6 +494,9 @@ construct_runtime!(
 
 		// Westend bridge modules.
 		BridgeWestendGrandpa: pallet_bridge_grandpa::<Instance1>::{Pallet, Call, Config<T>, Storage},
+
+		// Pallet for sending XCM.
+		XcmPallet: pallet_xcm::{Pallet, Call, Storage, Event<T>, Origin, Config} = 99,
 	}
 );
 
@@ -750,6 +748,7 @@ impl_runtime_apis! {
 				Runtime,
 				WithRialtoMessagesInstance,
 				WithRialtoMessageBridge,
+				xcm_config::OutboundXcmWeigher,
 			>(lane, begin, end)
 		}
 	}

bridges/bin/millau/runtime/src/rialto_messages.rs

@@ -16,7 +16,7 @@
 
 //! Everything required to serve Millau <-> Rialto messages.
 
-use crate::Runtime;
+use crate::{Call, OriginCaller, Runtime};
 
 use bp_messages::{
 	source_chain::{SenderOrigin, TargetHeaderChain},
@@ -40,6 +40,10 @@ pub const INITIAL_RIALTO_TO_MILLAU_CONVERSION_RATE: FixedU128 =
 	FixedU128::from_inner(FixedU128::DIV);
 /// Initial value of `RialtoFeeMultiplier` parameter.
 pub const INITIAL_RIALTO_FEE_MULTIPLIER: FixedU128 = FixedU128::from_inner(FixedU128::DIV);
+/// Weight of 2 XCM instructions is for simple `Trap(42)` program, coming through bridge
+/// (it is prepended with `UniversalOrigin` instruction). It is used just for simplest manual
+/// tests, confirming that we don't break encoding somewhere between.
+pub const BASE_XCM_WEIGHT_TWICE: Weight = 2 * crate::xcm_config::BASE_XCM_WEIGHT;
 
 parameter_types! {
 	/// Rialto to Millau conversion rate. Initially we treat both tokens as equal.
@@ -56,7 +60,7 @@ pub type ToRialtoMessageVerifier =
 	messages::source::FromThisChainMessageVerifier<WithRialtoMessageBridge>;
 
 /// Message payload for Rialto -> Millau messages.
-pub type FromRialtoMessagePayload = messages::target::FromBridgedChainMessagePayload;
+pub type FromRialtoMessagePayload = messages::target::FromBridgedChainMessagePayload<Call>;
 
 /// Messages proof for Rialto -> Millau messages.
 pub type FromRialtoMessagesProof = messages::target::FromBridgedChainMessagesProof<bp_rialto::Hash>;
@@ -68,9 +72,11 @@ pub type ToRialtoMessagesDeliveryProof =
 /// Call-dispatch based message dispatch for Rialto -> Millau messages.
 pub type FromRialtoMessageDispatch = messages::target::FromBridgedChainMessageDispatch<
 	WithRialtoMessageBridge,
-	crate::Runtime,
-	pallet_balances::Pallet<Runtime>,
-	(),
+	xcm_executor::XcmExecutor<crate::xcm_config::XcmConfig>,
+	crate::xcm_config::XcmWeigher,
+	// 2 XCM instructions is for simple `Trap(42)` program, coming through bridge
+	// (it is prepended with `UniversalOrigin` instruction)
+	frame_support::traits::ConstU64<BASE_XCM_WEIGHT_TWICE>,
 >;
 
 /// Millau <-> Rialto message bridge.
@@ -115,7 +121,23 @@ impl messages::ThisChainWithMessages for Millau {
 	type Call = crate::Call;
 
 	fn is_message_accepted(send_origin: &Self::Origin, lane: &LaneId) -> bool {
-		(*lane == [0, 0, 0, 0] || *lane == [0, 0, 0, 1]) && send_origin.linked_account().is_some()
+		let here_location =
+			xcm::v3::MultiLocation::from(crate::xcm_config::UniversalLocation::get());
+		match send_origin.caller {
+			OriginCaller::XcmPallet(pallet_xcm::Origin::Xcm(ref location))
+				if *location == here_location =>
+			{
+				log::trace!(target: "runtime::bridge", "Verifying message sent using XCM pallet to Rialto");
+			},
+			_ => {
+				// keep in mind that in this case all messages are free (in term of fees)
+				// => it's just to keep testing bridge on our test deployments until we'll have a
+				// better option
+				log::trace!(target: "runtime::bridge", "Verifying message sent using messages pallet to Rialto");
+			},
+		}
+
+		*lane == [0, 0, 0, 0] || *lane == [0, 0, 0, 1]
 	}
 
 	fn maximal_pending_messages_at_outbound_lane() -> MessageNonce {
@@ -262,14 +284,8 @@ impl SourceHeaderChain<bp_rialto::Balance> for Rialto {
 
 impl SenderOrigin<crate::AccountId> for crate::Origin {
 	fn linked_account(&self) -> Option<crate::AccountId> {
-		match self.caller {
-			crate::OriginCaller::system(frame_system::RawOrigin::Signed(ref submitter)) =>
-				Some(submitter.clone()),
-			crate::OriginCaller::system(frame_system::RawOrigin::Root) |
-			crate::OriginCaller::system(frame_system::RawOrigin::None) =>
-				crate::RootAccountForPayments::get(),
-			_ => None,
-		}
+		// XCM deals wit fees in our deployments
+		None
 	}
 }