Add support for pallet-xcm precompile (#35)

* add pallet-xcm precompile

* update interface docs

* update comment for Unlimited weight

* add comment in record_cost

* mock cleanup

* remove custom address from solidity interface

* start converter implementation (PoC)

* use size_of in AssetIdInfo

* fmt

* refactor converter

* fmt

* add Erc20PalletMatcher and adapt mock

* remove unused import

* minor fixes

* add new functions

* refactor ForeignAssetMatcher

* rust fmt

* add more tests and handle db reads costs

* fix tests

* use proper origin in mock

* update solidity interface docs

* remove TODO comment

Cargo.toml

@@ -52,6 +52,8 @@ flume = "0.11.0"
 jsonrpsee = { version = "0.20.3" }
 hex-literal = "0.4.1"
 
+# Moonkit
+pallet-foreign-asset-creator = { path = "pallets/foreign-asset-creator", default-features = false }
 
 # Substrate (wasm)
 frame-benchmarking = { git = "https://github.com/paritytech/polkadot-sdk", branch = "release-polkadot-v1.7.0", default-features = false }

precompiles/assets-erc20/Cargo.toml

@@ -27,6 +27,9 @@ sp-std = { workspace = true }
 fp-evm = { workspace = true }
 pallet-evm = { workspace = true, features = [ "forbid-evm-reentrancy" ] }
 
+# Moonkit
+xcm-primitives = { workspace = true }
+
 [dev-dependencies]
 hex-literal = { workspace = true }
 libsecp256k1 = { workspace = true }
@@ -57,4 +60,5 @@ std = [
 	"sp-io/std",
 	"sp-runtime/std",
 	"sp-std/std",
+	"xcm-primitives/std",
 ]

precompiles/assets-erc20/src/lib.rs

@@ -38,6 +38,7 @@ use sp_std::{
 	convert::{TryFrom, TryInto},
 	marker::PhantomData,
 };
+use xcm_primitives::AccountIdAssetIdConversion;
 
 mod eip2612;
 use eip2612::Eip2612;
@@ -59,16 +60,6 @@ pub type BalanceOf<Runtime, Instance = ()> = <Runtime as pallet_assets::Config<I
 /// Alias for the Asset Id type for the provided Runtime and Instance.
 pub type AssetIdOf<Runtime, Instance = ()> = <Runtime as pallet_assets::Config<Instance>>::AssetId;
 
-/// This trait ensure we can convert AccountIds to AssetIds
-/// We will require Runtime to have this trait implemented
-pub trait AccountIdAssetIdConversion<Account, AssetId> {
-	// Get assetId and prefix from account
-	fn account_to_asset_id(account: Account) -> Option<(Vec<u8>, AssetId)>;
-
-	// Get AccountId from AssetId and prefix
-	fn asset_id_to_account(prefix: &[u8], asset_id: AssetId) -> Account;
-}
-
 /// The following distribution has been decided for the precompiles
 /// 0-1023: Ethereum Mainnet Precompiles
 /// 1024-2047 Precompiles that are not in Ethereum Mainnet but are neither Moonbeam specific

precompiles/assets-erc20/src/mock.rs

@@ -36,6 +36,7 @@ use sp_runtime::{
 	traits::{BlakeTwo256, ConstU32, IdentityLookup},
 	BuildStorage,
 };
+use xcm_primitives::AccountIdAssetIdConversion;
 
 pub type AccountId = MockAccount;
 pub type AssetId = u128;

precompiles/pallet-xcm/Cargo.toml

@@ -0,0 +1,76 @@
+[package]
+name = "pallet-evm-precompile-xcm"
+authors = { workspace = true }
+description = "A Precompile to make pallet-xcm accessible to pallet-evm"
+edition = "2021"
+version = "0.1.0"
+
+[dependencies]
+log = { workspace = true }
+num_enum = { workspace = true }
+
+# Moonbeam
+precompile-utils = { workspace = true }
+xcm-primitives = { workspace = true }
+
+# Substrate
+frame-support = { workspace = true }
+frame-system = { workspace = true }
+sp-core = { workspace = true }
+sp-runtime = { workspace = true }
+sp-std = { workspace = true }
+sp-weights = { workspace = true }
+
+# Frontier
+evm = { workspace = true, features = [ "with-codec" ] }
+fp-evm = { workspace = true }
+pallet-evm = { workspace = true, features = [ "forbid-evm-reentrancy" ] }
+
+# Polkadot
+xcm = { workspace = true }
+pallet-xcm = { workspace = true }
+
+# Cumulus
+cumulus-primitives-core = { workspace = true }
+
+[dev-dependencies]
+derive_more = { workspace = true }
+
+# Moonbeam
+precompile-utils = { workspace = true, features = [ "testing", "codec-xcm" ] }
+xcm-primitives = { workspace = true }
+
+# Substrate
+pallet-assets = { workspace = true, features = [ "std" ] }
+pallet-balances = { workspace = true, features = [ "std", "insecure_zero_ed" ] }
+pallet-foreign-asset-creator = { workspace = true, features = [ "std" ] }
+pallet-timestamp = { workspace = true }
+parity-scale-codec = { workspace = true, features = [ "max-encoded-len" ] }
+scale-info = { workspace = true, features = [ "derive" ] }
+sp-io = { workspace = true }
+
+# Polkadot
+xcm-builder = { workspace = true }
+xcm-executor = { workspace = true }
+
+[features]
+default = [ "std" ]
+std = [
+	"cumulus-primitives-core/std",
+	"frame-support/std",
+	"frame-system/std",
+	"pallet-evm/std",
+    "pallet-xcm/std",
+	"precompile-utils/std",
+	"sp-core/std",
+	"sp-std/std",
+	"xcm/std",
+	"xcm-builder/std",
+	"xcm-executor/std",
+	"xcm-primitives/std",
+]
+runtime-benchmarks = [
+	"frame-support/runtime-benchmarks",
+	"frame-system/runtime-benchmarks",
+	"xcm-builder/runtime-benchmarks",
+]

precompiles/pallet-xcm/XcmInterface.sol

@@ -0,0 +1,96 @@
+// SPDX-License-Identifier: GPL-3.0-only
+pragma solidity >=0.8.3;
+
+/// @author The Moonbeam Team
+/// @title XCM precompile Interface
+/// @dev The interface that Solidity contracts use to interact with the substrate pallet-xcm.
+interface XCM {
+    // A location is defined by its number of parents and the encoded junctions (interior)
+    struct Location {
+        uint8 parents;
+        bytes[] interior;
+    }
+
+    // Support for Weights V2
+    struct Weight {
+        uint64 refTime;
+        uint64 proofSize;
+    }
+
+    // A way to represent fungible assets in XCM using Location format
+    struct AssetLocationInfo {
+        Location location;
+        uint256 amount;
+    }
+
+    // A way to represent fungible assets in XCM using address format
+    struct AssetAddressInfo {
+        address asset;
+        uint256 amount;
+    }
+
+    /// @dev Function to send assets via XCM using transfer_assets() pallet-xcm extrinsic.
+    /// @custom:selector 59df8416
+    /// @param dest The destination chain.
+    /// @param beneficiary The actual account that will receive the tokens on dest.
+    /// @param assets The combination (array) of assets to send.
+    /// @param feeAssetItem The index of the asset that will be used to pay for fees.
+    /// @param weight The weight to be used for the whole XCM operation.
+    /// (uint64::MAX in refTime means Unlimited weight) 
+    function transferAssetsLocation(
+        Location memory dest,
+        Location memory beneficiary,
+        AssetLocationInfo[] memory assets,
+        uint32 feeAssetItem,
+        Weight memory weight
+    ) external;
+
+    /// @dev Function to send assets via XCM to a 20 byte-like parachain 
+    /// using transfer_assets() pallet-xcm extrinsic.
+    /// @custom:selector b489262e
+    /// @param paraId The para-id of the destination chain.
+    /// @param beneficiary The actual account that will receive the tokens on paraId destination.
+    /// @param assets The combination (array) of assets to send.
+    /// @param feeAssetItem The index of the asset that will be used to pay for fees.
+    /// @param weight The weight to be used for the whole XCM operation.
+    /// (uint64::MAX in refTime means Unlimited weight)
+    function transferAssetsToPara20(
+        uint32 paraId,
+        address beneficiary,
+        AssetAddressInfo[] memory assets,
+        uint32 feeAssetItem,
+        Weight memory weight
+    ) external;
+
+    /// @dev Function to send assets via XCM to a 32 byte-like parachain 
+    /// using transfer_assets() pallet-xcm extrinsic.
+    /// @custom:selector 4461e6f5
+    /// @param paraId The para-id of the destination chain.
+    /// @param beneficiary The actual account that will receive the tokens on paraId destination.
+    /// @param assets The combination (array) of assets to send.
+    /// @param feeAssetItem The index of the asset that will be used to pay for fees.
+    /// @param weight The weight to be used for the whole XCM operation.
+    /// (uint64::MAX in refTime means Unlimited weight)
+    function transferAssetsToPara32(
+        uint32 paraId,
+        bytes32 beneficiary,
+        AssetAddressInfo[] memory assets,
+        uint32 feeAssetItem,
+        Weight memory weight
+    ) external;
+
+    /// @dev Function to send assets via XCM to the relay chain 
+    /// using transfer_assets() pallet-xcm extrinsic.
+    /// @custom:selector d7c89659
+    /// @param beneficiary The actual account that will receive the tokens on the relay chain.
+    /// @param assets The combination (array) of assets to send.
+    /// @param feeAssetItem The index of the asset that will be used to pay for fees.
+    /// @param weight The weight to be used for the whole XCM operation.
+    /// (uint64::MAX in refTime means Unlimited weight)
+    function transferAssetsToRelay(
+        bytes32 beneficiary,
+        AssetAddressInfo[] memory assets,
+        uint32 feeAssetItem,
+        Weight memory weight
+    ) external;
+}