Support external account provider

frame/ethereum/src/mock.rs

@@ -159,6 +159,7 @@ parameter_types! {
 }
 
 impl pallet_evm::Config for Test {
+	type AccountProvider = pallet_evm::NativeSystemAccountProvider<Self>;
 	type FeeCalculator = FixedGasPrice;
 	type GasWeightMapping = pallet_evm::FixedGasWeightMapping<Self>;
 	type WeightPerGas = WeightPerGas;

frame/evm/precompile/dispatch/src/lib.rs

@@ -54,8 +54,8 @@ impl<T, DispatchValidator, DecodeLimit> Precompile for Dispatch<T, DispatchValid
 where
 	T: pallet_evm::Config,
 	T::RuntimeCall: Dispatchable<PostInfo = PostDispatchInfo> + GetDispatchInfo + Decode,
-	<T::RuntimeCall as Dispatchable>::RuntimeOrigin: From<Option<T::AccountId>>,
-	DispatchValidator: DispatchValidateT<T::AccountId, T::RuntimeCall>,
+	<T::RuntimeCall as Dispatchable>::RuntimeOrigin: From<Option<pallet_evm::AccountIdOf<T>>>,
+	DispatchValidator: DispatchValidateT<pallet_evm::AccountIdOf<T>, T::RuntimeCall>,
 	DecodeLimit: Get<u32>,
 {
 	fn execute(handle: &mut impl PrecompileHandle) -> PrecompileResult {

frame/evm/precompile/dispatch/src/mock.rs

@@ -136,6 +136,7 @@ parameter_types! {
 	pub SuicideQuickClearLimit: u32 = 0;
 }
 impl pallet_evm::Config for Test {
+	type AccountProvider = pallet_evm::NativeSystemAccountProvider<Self>;
 	type FeeCalculator = FixedGasPrice;
 	type GasWeightMapping = pallet_evm::FixedGasWeightMapping<Self>;
 	type WeightPerGas = WeightPerGas;

frame/evm/precompile/storage-cleaner/src/lib.rs

@@ -23,7 +23,9 @@ extern crate alloc;
 
 use alloc::vec::Vec;
 use core::marker::PhantomData;
-use fp_evm::{PrecompileFailure, ACCOUNT_BASIC_PROOF_SIZE, ACCOUNT_STORAGE_PROOF_SIZE};
+use fp_evm::{
+	AccountProvider, PrecompileFailure, ACCOUNT_BASIC_PROOF_SIZE, ACCOUNT_STORAGE_PROOF_SIZE,
+};
 use pallet_evm::AddressMapping;
 use precompile_utils::{prelude::*, EvmResult};
 use sp_core::H160;
@@ -200,7 +202,7 @@ where
 		pallet_evm::Suicided::<Runtime>::remove(address);
 
 		let account_id = Runtime::AddressMapping::into_account_id(address);
-		let _ = frame_system::Pallet::<Runtime>::dec_sufficients(&account_id);
+		Runtime::AccountProvider::remove_account(&account_id);
 	}
 }
 

frame/evm/precompile/storage-cleaner/src/mock.rs

@@ -124,6 +124,7 @@ parameter_types! {
 }
 
 impl pallet_evm::Config for Runtime {
+	type AccountProvider = pallet_evm::NativeSystemAccountProvider<Self>;
 	type FeeCalculator = ();
 	type GasWeightMapping = pallet_evm::FixedGasWeightMapping<Self>;
 	type WeightPerGas = WeightPerGas;

frame/evm/src/lib.rs

@@ -102,9 +102,10 @@ use sp_runtime::{
 use fp_account::AccountId20;
 use fp_evm::GenesisAccount;
 pub use fp_evm::{
-	Account, CallInfo, CreateInfo, ExecutionInfoV2 as ExecutionInfo, FeeCalculator,
-	IsPrecompileResult, LinearCostPrecompile, Log, Precompile, PrecompileFailure, PrecompileHandle,
-	PrecompileOutput, PrecompileResult, PrecompileSet, TransactionValidationError, Vicinity,
+	Account, AccountProvider, CallInfo, CreateInfo, ExecutionInfoV2 as ExecutionInfo,
+	FeeCalculator, IsPrecompileResult, LinearCostPrecompile, Log, Precompile, PrecompileFailure,
+	PrecompileHandle, PrecompileOutput, PrecompileResult, PrecompileSet,
+	TransactionValidationError, Vicinity,
 };
 
 pub use self::{
@@ -125,6 +126,9 @@ pub mod pallet {
 
 	#[pallet::config]
 	pub trait Config: frame_system::Config {
+		/// Account info provider.
+		type AccountProvider: AccountProvider;
+
 		/// Calculator for current gas price.
 		type FeeCalculator: FeeCalculator;
 
@@ -140,12 +144,12 @@ pub mod pallet {
 		/// Allow the origin to call on behalf of given address.
 		type CallOrigin: EnsureAddressOrigin<Self::RuntimeOrigin>;
 		/// Allow the origin to withdraw on behalf of given address.
-		type WithdrawOrigin: EnsureAddressOrigin<Self::RuntimeOrigin, Success = Self::AccountId>;
+		type WithdrawOrigin: EnsureAddressOrigin<Self::RuntimeOrigin, Success = AccountIdOf<Self>>;
 
 		/// Mapping from address to account id.
-		type AddressMapping: AddressMapping<Self::AccountId>;
+		type AddressMapping: AddressMapping<AccountIdOf<Self>>;
 		/// Currency type for withdraw and balance storage.
-		type Currency: Currency<Self::AccountId> + Inspect<Self::AccountId>;
+		type Currency: Currency<AccountIdOf<Self>> + Inspect<AccountIdOf<Self>>;
 
 		/// The overarching event type.
 		type RuntimeEvent: From<Event<Self>> + IsType<<Self as frame_system::Config>::RuntimeEvent>;
@@ -551,7 +555,7 @@ pub mod pallet {
 					MAX_ACCOUNT_NONCE,
 					UniqueSaturatedInto::<usize>::unique_saturated_into(account.nonce),
 				) {
-					frame_system::Pallet::<T>::inc_account_nonce(&account_id);
+					T::AccountProvider::inc_account_nonce(&account_id);
 				}
 
 				let _ = T::Currency::deposit_creating(
@@ -583,13 +587,14 @@ pub mod pallet {
 	pub type Suicided<T: Config> = StorageMap<_, Blake2_128Concat, H160, (), OptionQuery>;
 }
 
+/// Utility alias for easy access to the [`AccountProvider::AccountId`] type from a given config.
+pub type AccountIdOf<T> = <<T as Config>::AccountProvider as AccountProvider>::AccountId;
+
 /// Type alias for currency balance.
-pub type BalanceOf<T> =
-	<<T as Config>::Currency as Currency<<T as frame_system::Config>::AccountId>>::Balance;
+pub type BalanceOf<T> = <<T as Config>::Currency as Currency<AccountIdOf<T>>>::Balance;
 
 /// Type alias for negative imbalance during fees
-type NegativeImbalanceOf<C, T> =
-	<C as Currency<<T as frame_system::Config>::AccountId>>::NegativeImbalance;
+type NegativeImbalanceOf<C, T> = <C as Currency<AccountIdOf<T>>>::NegativeImbalance;
 
 #[derive(
 	Debug,
@@ -827,7 +832,7 @@ impl<T: Config> Pallet<T> {
 			// In theory, we can always have pre-EIP161 contracts, so we
 			// make sure the account nonce is at least one.
 			let account_id = T::AddressMapping::into_account_id(*address);
-			frame_system::Pallet::<T>::inc_account_nonce(&account_id);
+			T::AccountProvider::inc_account_nonce(&account_id);
 		}
 
 		<AccountCodes<T>>::remove(address);
@@ -842,7 +847,7 @@ impl<T: Config> Pallet<T> {
 					<Suicided<T>>::remove(address);
 
 					let account_id = T::AddressMapping::into_account_id(*address);
-					let _ = frame_system::Pallet::<T>::dec_sufficients(&account_id);
+					T::AccountProvider::remove_account(&account_id);
 				}
 				KillStorageResult::SomeRemaining(_) => (),
 			}
@@ -865,7 +870,7 @@ impl<T: Config> Pallet<T> {
 
 		if !<AccountCodes<T>>::contains_key(address) {
 			let account_id = T::AddressMapping::into_account_id(address);
-			let _ = frame_system::Pallet::<T>::inc_sufficients(&account_id);
+			T::AccountProvider::create_account(&account_id);
 		}
 
 		// Update metadata.
@@ -905,7 +910,7 @@ impl<T: Config> Pallet<T> {
 	/// Get the account basic in EVM format.
 	pub fn account_basic(address: &H160) -> (Account, frame_support::weights::Weight) {
 		let account_id = T::AddressMapping::into_account_id(*address);
-		let nonce = frame_system::Pallet::<T>::account_nonce(&account_id);
+		let nonce = T::AccountProvider::account_nonce(&account_id);
 		let balance =
 			T::Currency::reducible_balance(&account_id, Preservation::Preserve, Fortitude::Polite);
 
@@ -961,17 +966,13 @@ pub struct EVMCurrencyAdapter<C, OU>(core::marker::PhantomData<(C, OU)>);
 impl<T, C, OU> OnChargeEVMTransaction<T> for EVMCurrencyAdapter<C, OU>
 where
 	T: Config,
-	C: Currency<<T as frame_system::Config>::AccountId>,
-	C::PositiveImbalance: Imbalance<
-		<C as Currency<<T as frame_system::Config>::AccountId>>::Balance,
-		Opposite = C::NegativeImbalance,
-	>,
-	C::NegativeImbalance: Imbalance<
-		<C as Currency<<T as frame_system::Config>::AccountId>>::Balance,
-		Opposite = C::PositiveImbalance,
-	>,
+	C: Currency<AccountIdOf<T>>,
+	C::PositiveImbalance:
+		Imbalance<<C as Currency<AccountIdOf<T>>>::Balance, Opposite = C::NegativeImbalance>,
+	C::NegativeImbalance:
+		Imbalance<<C as Currency<AccountIdOf<T>>>::Balance, Opposite = C::PositiveImbalance>,
 	OU: OnUnbalanced<NegativeImbalanceOf<C, T>>,
-	U256: UniqueSaturatedInto<<C as Currency<<T as frame_system::Config>::AccountId>>::Balance>,
+	U256: UniqueSaturatedInto<<C as Currency<AccountIdOf<T>>>::Balance>,
 {
 	// Kept type as Option to satisfy bound of Default
 	type LiquidityInfo = Option<NegativeImbalanceOf<C, T>>;
@@ -1061,12 +1062,12 @@ pub struct EVMFungibleAdapter<F, OU>(core::marker::PhantomData<(F, OU)>);
 impl<T, F, OU> OnChargeEVMTransaction<T> for EVMFungibleAdapter<F, OU>
 where
 	T: Config,
-	F: Balanced<T::AccountId>,
-	OU: OnUnbalanced<Credit<T::AccountId, F>>,
-	U256: UniqueSaturatedInto<<F as Inspect<<T as frame_system::Config>::AccountId>>::Balance>,
+	F: Balanced<AccountIdOf<T>>,
+	OU: OnUnbalanced<Credit<AccountIdOf<T>, F>>,
+	U256: UniqueSaturatedInto<<F as Inspect<AccountIdOf<T>>>::Balance>,
 {
 	// Kept type as Option to satisfy bound of Default
-	type LiquidityInfo = Option<Credit<T::AccountId, F>>;
+	type LiquidityInfo = Option<Credit<AccountIdOf<T>, F>>;
 
 	fn withdraw_fee(who: &H160, fee: U256) -> Result<Self::LiquidityInfo, Error<T>> {
 		if fee.is_zero() {
@@ -1099,13 +1100,13 @@ where
 				.saturating_sub(corrected_fee.unique_saturated_into());
 			// refund to the account that paid the fees.
 			let refund_imbalance = F::deposit(&account_id, refund_amount, Precision::BestEffort)
-				.unwrap_or_else(|_| Debt::<T::AccountId, F>::zero());
+				.unwrap_or_else(|_| Debt::<AccountIdOf<T>, F>::zero());
 
 			// merge the imbalance caused by paying the fees and refunding parts of it again.
 			let adjusted_paid = paid
 				.offset(refund_imbalance)
 				.same()
-				.unwrap_or_else(|_| Credit::<T::AccountId, F>::zero());
+				.unwrap_or_else(|_| Credit::<AccountIdOf<T>, F>::zero());
 
 			let (base_fee, tip) = adjusted_paid.split(base_fee.unique_saturated_into());
 			// Handle base fee. Can be either burned, rationed, etc ...
@@ -1128,13 +1129,11 @@ where
 impl<T> OnChargeEVMTransaction<T> for ()
 where
 	T: Config,
-	T::Currency: Balanced<T::AccountId>,
-	U256: UniqueSaturatedInto<
-		<<T as Config>::Currency as Inspect<<T as frame_system::Config>::AccountId>>::Balance,
-	>,
+	T::Currency: Balanced<AccountIdOf<T>>,
+	U256: UniqueSaturatedInto<<<T as Config>::Currency as Inspect<AccountIdOf<T>>>::Balance>,
 {
 	// Kept type as Option to satisfy bound of Default
-	type LiquidityInfo = Option<Credit<T::AccountId, T::Currency>>;
+	type LiquidityInfo = Option<Credit<AccountIdOf<T>, T::Currency>>;
 
 	fn withdraw_fee(who: &H160, fee: U256) -> Result<Self::LiquidityInfo, Error<T>> {
 		EVMFungibleAdapter::<T::Currency, ()>::withdraw_fee(who, fee)
@@ -1175,3 +1174,26 @@ impl<T> OnCreate<T> for Tuple {
 		)*)
 	}
 }
+
+/// Native system account provider that `frame_system` provides.
+pub struct NativeSystemAccountProvider<T>(core::marker::PhantomData<T>);
+
+impl<T: frame_system::Config> AccountProvider for NativeSystemAccountProvider<T> {
+	type AccountId = T::AccountId;
+	type Nonce = T::Nonce;
+
+	fn account_nonce(who: &Self::AccountId) -> Self::Nonce {
+		frame_system::Pallet::<T>::account_nonce(who)
+	}
+
+	fn inc_account_nonce(who: &Self::AccountId) {
+		frame_system::Pallet::<T>::inc_account_nonce(who)
+	}
+
+	fn create_account(who: &Self::AccountId) {
+		let _ = frame_system::Pallet::<T>::inc_sufficients(who);
+	}
+	fn remove_account(who: &Self::AccountId) {
+		let _ = frame_system::Pallet::<T>::dec_sufficients(who);
+	}
+}

frame/evm/src/mock.rs

@@ -134,6 +134,7 @@ parameter_types! {
 	pub SuicideQuickClearLimit: u32 = 0;
 }
 impl crate::Config for Test {
+	type AccountProvider = crate::NativeSystemAccountProvider<Self>;
 	type FeeCalculator = FixedGasPrice;
 	type GasWeightMapping = crate::FixedGasWeightMapping<Self>;
 	type WeightPerGas = WeightPerGas;

frame/evm/src/runner/stack.rs

@@ -47,9 +47,9 @@ use fp_evm::{
 };
 
 use crate::{
-	runner::Runner as RunnerT, AccountCodes, AccountCodesMetadata, AccountStorages, AddressMapping,
-	BalanceOf, BlockHashMapping, Config, Error, Event, FeeCalculator, OnChargeEVMTransaction,
-	OnCreate, Pallet, RunnerError,
+	runner::Runner as RunnerT, AccountCodes, AccountCodesMetadata, AccountProvider,
+	AccountStorages, AddressMapping, BalanceOf, BlockHashMapping, Config, Error, Event,
+	FeeCalculator, OnChargeEVMTransaction, OnCreate, Pallet, RunnerError,
 };
 
 #[cfg(feature = "forbid-evm-reentrancy")]
@@ -840,7 +840,7 @@ where
 
 	fn inc_nonce(&mut self, address: H160) -> Result<(), ExitError> {
 		let account_id = T::AddressMapping::into_account_id(address);
-		frame_system::Pallet::<T>::inc_account_nonce(&account_id);
+		T::AccountProvider::inc_account_nonce(&account_id);
 		Ok(())
 	}
 

precompiles/src/precompile_set.rs

@@ -1085,7 +1085,7 @@ impl<R: pallet_evm::Config, P: PrecompileSetFragment> PrecompileSetBuilder<R, P>
 	}
 
 	/// Return the list of mapped addresses contained in this PrecompileSet.
-	pub fn used_addresses() -> impl Iterator<Item = R::AccountId> {
+	pub fn used_addresses() -> impl Iterator<Item = pallet_evm::AccountIdOf<R>> {
 		Self::used_addresses_h160().map(R::AddressMapping::into_account_id)
 	}
 

precompiles/tests-external/lib.rs

@@ -230,6 +230,7 @@ parameter_types! {
 }
 
 impl pallet_evm::Config for Runtime {
+	type AccountProvider = pallet_evm::NativeSystemAccountProvider<Self>;
 	type FeeCalculator = ();
 	type GasWeightMapping = pallet_evm::FixedGasWeightMapping<Self>;
 	type WeightPerGas = WeightPerGas;

primitives/evm/src/account_provider.rs

@@ -0,0 +1,41 @@
+//! Custom account provider logic.
+
+use sp_runtime::traits::AtLeast32Bit;
+
+/// The account provider interface abstraction layer.
+///
+/// Expose account related logic that `pallet_evm` required to control accounts existence
+/// in the network and their transactions uniqueness. By default, the pallet operates native
+/// system accounts records that `frame_system` provides.
+///
+/// The interface allow any custom account provider logic to be used instead of
+/// just using `frame_system` account provider. The accounts records should store nonce value
+/// for each account at least.
+pub trait AccountProvider {
+	/// The account identifier type.
+	///
+	/// Represent the account itself in accounts records.
+	type AccountId;
+	/// Account nonce type.
+	///
+	/// The number that helps to ensure that each transaction in the network is unique
+	/// for particular account.
+	type Nonce: AtLeast32Bit;
+
+	/// Creates a new account in accounts records.
+	///
+	/// The account associated with new created address EVM.
+	fn create_account(who: &Self::AccountId);
+	/// Removes an account from accounts records.
+	///
+	/// The account associated with removed address from EVM.
+	fn remove_account(who: &Self::AccountId);
+	/// Return current account nonce value.
+	///
+	/// Used to represent account basic information in EVM format.
+	fn account_nonce(who: &Self::AccountId) -> Self::Nonce;
+	/// Increment a particular account's nonce value.
+	///
+	/// Incremented with each new transaction submitted by the account.
+	fn inc_account_nonce(who: &Self::AccountId);
+}

primitives/evm/src/lib.rs

@@ -20,6 +20,7 @@
 
 extern crate alloc;
 
+mod account_provider;
 mod precompile;
 mod validation;
 
@@ -38,6 +39,7 @@ pub use evm::{
 };
 
 pub use self::{
+	account_provider::AccountProvider,
 	precompile::{
 		Context, ExitError, ExitRevert, ExitSucceed, IsPrecompileResult, LinearCostPrecompile,
 		Precompile, PrecompileFailure, PrecompileHandle, PrecompileOutput, PrecompileResult,

template/runtime/src/lib.rs

@@ -348,6 +348,7 @@ parameter_types! {
 }
 
 impl pallet_evm::Config for Runtime {
+	type AccountProvider = pallet_evm::NativeSystemAccountProvider<Self>;
 	type FeeCalculator = BaseFee;
 	type GasWeightMapping = pallet_evm::FixedGasWeightMapping<Self>;
 	type WeightPerGas = WeightPerGas;