Automatic EVM revert code registration for XC20 (#1001)

* Automatic EVM revert code registration for XC20

* Add negative test

* Fmt fix

* Add EVM module

* Asset benchmarks

* Cleanup xc asset config

* Update asset benchmarks

* Fix tests features

pallets/xc-asset-config/src/lib.rs

@@ -85,21 +85,6 @@ pub mod pallet {
     #[pallet::without_storage_info]
     pub struct Pallet<T>(PhantomData<T>);
 
-    /// Callback definition trait for cross-chain asset registration/deregistration notifications.
-    pub trait XcAssetChanged<T: Config> {
-        /// Will be called by pallet when new asset Id has been registered
-        fn xc_asset_registered(asset_id: T::AssetId);
-
-        /// Will be called by pallet when asset Id has been unregistered
-        fn xc_asset_unregistered(asset_id: T::AssetId);
-    }
-
-    /// Implementation that does nothing
-    impl<T: Config> XcAssetChanged<T> for () {
-        fn xc_asset_registered(_: T::AssetId) {}
-        fn xc_asset_unregistered(_: T::AssetId) {}
-    }
-
     /// Defines conversion between asset Id and cross-chain asset location
     pub trait XcAssetLocation<AssetId> {
         /// Get asset type from assetId
@@ -139,9 +124,6 @@ pub mod pallet {
         /// a AssetLocation
         type AssetId: Member + Parameter + Default + Copy + HasCompact + MaxEncodedLen;
 
-        /// Callback handling for cross-chain asset registration or unregistration.
-        type XcAssetChanged: XcAssetChanged<Self>;
-
         /// The required origin for managing cross-chain asset configuration
         ///
         /// Should most likely be root.
@@ -242,8 +224,6 @@ pub mod pallet {
             AssetIdToLocation::<T>::insert(&asset_id, asset_location.clone());
             AssetLocationToId::<T>::insert(&asset_location, asset_id);
 
-            T::XcAssetChanged::xc_asset_registered(asset_id);
-
             Self::deposit_event(Event::AssetRegistered {
                 asset_location,
                 asset_id,
@@ -354,7 +334,6 @@ pub mod pallet {
             AssetIdToLocation::<T>::remove(&asset_id);
             AssetLocationToId::<T>::remove(&asset_location);
             AssetLocationUnitsPerSecond::<T>::remove(&asset_location);
-            T::XcAssetChanged::xc_asset_unregistered(asset_id);
 
             Self::deposit_event(Event::AssetRemoved {
                 asset_id,

pallets/xc-asset-config/src/mock.rs

@@ -108,7 +108,6 @@ type AssetId = u128;
 impl pallet_xc_asset_config::Config for Test {
     type RuntimeEvent = RuntimeEvent;
     type AssetId = AssetId;
-    type XcAssetChanged = ();
     type ManagerOrigin = frame_system::EnsureRoot<AccountId>;
     type WeightInfo = ();
 }

precompiles/assets-erc20/Cargo.toml

@@ -55,3 +55,4 @@ std = [
 	"sp-runtime/std",
 	"sp-std/std",
 ]
+runtime-benchmarks = []

precompiles/assets-erc20/src/mock.rs

@@ -283,6 +283,8 @@ impl pallet_assets::Config for Runtime {
     type RemoveItemsLimit = ConstU32<0>;
     type AssetIdParameter = AssetId;
     type CallbackHandle = ();
+    #[cfg(feature = "runtime-benchmarks")]
+    type BenchmarkHelper = ();
 }
 
 // Configure a mock runtime to test the pallet.

precompiles/xcm/src/mock.rs

@@ -270,6 +270,8 @@ impl pallet_assets::Config for Runtime {
     type RemoveItemsLimit = ConstU32<0>;
     type AssetIdParameter = AssetId;
     type CallbackHandle = ();
+    #[cfg(feature = "runtime-benchmarks")]
+    type BenchmarkHelper = ();
 }
 
 pub struct AssetIdConverter<AssetId>(PhantomData<AssetId>);

primitives/Cargo.toml

@@ -20,6 +20,7 @@ fp-evm = { workspace = true }
 
 # Substrate dependencies
 frame-support = { workspace = true }
+pallet-assets = { workspace = true }
 sp-core = { workspace = true }
 sp-io = { workspace = true }
 sp-runtime = { workspace = true }
@@ -30,7 +31,11 @@ xcm = { workspace = true }
 xcm-builder = { workspace = true }
 xcm-executor = { workspace = true }
 
-# Astar pallets
+# Frontier dependencies
+pallet-evm = { workspace = true }
+
+# Astar pallets & dependencies
+pallet-evm-precompile-assets-erc20 = { workspace = true }
 pallet-xc-asset-config = { workspace = true }
 
 [features]
@@ -52,5 +57,8 @@ std = [
 	"xcm-executor/std",
 	"pallet-xc-asset-config/std",
 	"fp-evm/std",
+	"pallet-assets/std",
+	"pallet-evm/std",
+	"pallet-evm-precompile-assets-erc20/std",
 ]
-runtime-benchmarks = ["xcm-builder/runtime-benchmarks"]
+runtime-benchmarks = ["xcm-builder/runtime-benchmarks", "pallet-assets/runtime-benchmarks"]

primitives/src/benchmarks.rs

@@ -0,0 +1,30 @@
+// This file is part of Astar.
+
+// Copyright (C) 2019-2023 Stake Technologies Pte.Ltd.
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+// Astar is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Astar is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Astar. If not, see <http://www.gnu.org/licenses/>.
+
+use crate::AssetId;
+
+#[cfg(feature = "runtime-benchmarks")]
+/// Benchmark helper for `pallet-assets`.
+pub struct AssetsBenchmarkHelper;
+impl<AssetIdParameter: From<u128>> pallet_assets::BenchmarkHelper<AssetIdParameter>
+    for AssetsBenchmarkHelper
+{
+    fn create_asset_id_parameter(id: u32) -> AssetIdParameter {
+        AssetId::from(id).into()
+    }
+}

primitives/src/evm.rs

@@ -0,0 +1,56 @@
+// This file is part of Astar.
+
+// Copyright (C) 2019-2023 Stake Technologies Pte.Ltd.
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+// Astar is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Astar is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Astar. If not, see <http://www.gnu.org/licenses/>.
+
+use crate::{AccountId, AssetId};
+
+use frame_support::ensure;
+use sp_std::marker::PhantomData;
+
+use pallet_assets::AssetsCallback;
+use pallet_evm_precompile_assets_erc20::AddressToAssetId;
+
+/// Revert opt code. It's inserted at the precompile addresses, to make them functional in EVM.
+pub const EVM_REVERT_CODE: &[u8] = &[0x60, 0x00, 0x60, 0x00, 0xfd];
+
+/// Handler for automatic revert code registration.
+///
+/// When an asset is created, it automatically becomes available to the EVM via an `ERC20-like` interface.
+/// In order for the precompile to work, dedicated asset address needs to have the revert code registered, otherwise the call will fail.
+///
+/// It is important to note that if the dedicated asset EVM address is already taken, asset creation should fail.
+/// After asset has been destroyed, it is also safe to remove the revert code and free the address for future usage.
+pub struct EvmRevertCodeHandler<A, R>(PhantomData<(A, R)>);
+impl<A, R> AssetsCallback<AssetId, AccountId> for EvmRevertCodeHandler<A, R>
+where
+    A: AddressToAssetId<AssetId>,
+    R: pallet_evm::Config,
+{
+    fn created(id: &AssetId, _: &AccountId) -> Result<(), ()> {
+        let address = A::asset_id_to_address(*id);
+        // In case of collision, we need to cancel the asset creation.
+        ensure!(!pallet_evm::AccountCodes::<R>::contains_key(&address), ());
+        pallet_evm::AccountCodes::<R>::insert(address, EVM_REVERT_CODE.to_vec());
+        Ok(())
+    }
+
+    fn destroyed(id: &AssetId) -> Result<(), ()> {
+        let address = A::asset_id_to_address(*id);
+        pallet_evm::AccountCodes::<R>::remove(address);
+        Ok(())
+    }
+}

primitives/src/lib.rs

@@ -29,10 +29,16 @@ pub mod ethereum_checked;
 /// XVM primitives.
 pub mod xvm;
 
-use sp_runtime::traits::BlakeTwo256;
+/// EVM primitives.
+pub mod evm;
+
+/// Benchmark primitives
+#[cfg(feature = "runtime-benchmarks")]
+pub mod benchmarks;
+
 use sp_runtime::{
     generic,
-    traits::{IdentifyAccount, Verify},
+    traits::{BlakeTwo256, IdentifyAccount, Verify},
 };
 
 /// Alias to 512-bit hash when used in the context of a transaction signature on the chain.

primitives/src/xcm/mod.rs

@@ -33,8 +33,7 @@
 #![cfg_attr(not(feature = "std"), no_std)]
 
 use frame_support::{
-    ensure,
-    traits::{tokens::fungibles, Contains, ContainsPair, Get, ProcessMessageError},
+    traits::{tokens::fungibles, ContainsPair, Get},
     weights::constants::WEIGHT_REF_TIME_PER_SECOND,
 };
 use sp_runtime::traits::{Bounded, Zero};
@@ -43,7 +42,7 @@ use sp_std::{borrow::Borrow, marker::PhantomData, vec::Vec};
 // Polkadot imports
 use xcm::latest::{prelude::*, Weight};
 use xcm_builder::TakeRevenue;
-use xcm_executor::traits::{MatchesFungibles, ShouldExecute, WeightTrader};
+use xcm_executor::traits::{MatchesFungibles, WeightTrader};
 
 use pallet_xc_asset_config::{ExecutionPaymentRate, XcAssetLocation};
 
@@ -271,52 +270,6 @@ impl<
     }
 }
 
-/// Allows execution from `origin` if it is contained in `T` (i.e. `T::Contains(origin)`) taking
-/// payments into account.
-///
-/// Only allows for sequence `DescendOrigin` -> `WithdrawAsset` -> `BuyExecution`
-pub struct AllowPaidExecWithDescendOriginFrom<T>(PhantomData<T>);
-impl<T: Contains<MultiLocation>> ShouldExecute for AllowPaidExecWithDescendOriginFrom<T> {
-    fn should_execute<RuntimeCall>(
-        origin: &MultiLocation,
-        message: &mut [Instruction<RuntimeCall>],
-        max_weight: Weight,
-        _weight_credit: &mut Weight,
-    ) -> Result<(), ProcessMessageError> {
-        log::trace!(
-            target: "xcm::barriers",
-            "AllowPaidExecWithDescendOriginFrom origin: {:?}, message: {:?}, max_weight: {:?}, weight_credit: {:?}",
-            origin, message, max_weight, _weight_credit,
-        );
-        ensure!(T::contains(origin), ProcessMessageError::Unsupported);
-
-        match message
-            .iter_mut()
-            .take(3)
-            .collect::<Vec<_>>()
-            .as_mut_slice()
-        {
-            [DescendOrigin(..), WithdrawAsset(..), BuyExecution {
-                weight_limit: Limited(ref mut limit),
-                ..
-            }] if limit.all_gte(max_weight) => {
-                *limit = max_weight;
-                Ok(())
-            }
-
-            [DescendOrigin(..), WithdrawAsset(..), BuyExecution {
-                weight_limit: ref mut limit @ Unlimited,
-                ..
-            }] => {
-                *limit = Limited(max_weight);
-                Ok(())
-            }
-
-            _ => return Err(ProcessMessageError::Unsupported),
-        }
-    }
-}
-
 // TODO: remove this after uplift to `polkadot-v0.9.44` or beyond, and replace it with code in XCM builder.
 
 use parity_scale_codec::{Compact, Encode};