Allow for precompiles to have arbitrary addresses, potentially more than one.

frame/ethereum/src/mock.rs

@@ -169,6 +169,7 @@ impl pallet_evm::Config for Test {
 	type OnChargeTransaction = ();
 	type OnCreate = ();
 	type FindAuthor = FindAuthorTruncated;
+	type PrecompileModifierOrigin = frame_system::EnsureRoot<Self::AccountId>;
 }
 
 parameter_types! {

frame/evm/Cargo.toml

@@ -20,6 +20,7 @@ log = { version = "0.4.17", default-features = false }
 rlp = { workspace = true }
 scale-codec = { package = "parity-scale-codec", workspace = true }
 scale-info = { workspace = true }
+serde = { workspace = true, default-features = false }
 # Substrate
 frame-benchmarking = { workspace = true, optional = true }
 frame-support = { workspace = true }
@@ -40,6 +41,7 @@ pallet-evm-precompile-simple = { workspace = true }
 [features]
 default = ["std"]
 std = [
+	"serde/std",
 	"environmental?/std",
 	"evm/std",
 	"evm/with-serde",

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

@@ -159,6 +159,7 @@ impl pallet_evm::Config for Test {
 	type OnChargeTransaction = ();
 	type OnCreate = ();
 	type FindAuthor = FindAuthorTruncated;
+	type PrecompileModifierOrigin = frame_system::EnsureRoot<Self::AccountId>;
 }
 
 pub(crate) struct MockHandle {

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

@@ -73,8 +73,14 @@ pub fn new_test_ext() -> sp_io::TestExternalities {
 	}
 	.assimilate_storage(&mut t)
 	.expect("Pallet balances storage can be assimilated");
-	GenesisBuild::<Test>::assimilate_storage(&pallet_evm::GenesisConfig { accounts }, &mut t)
-		.unwrap();
+	GenesisBuild::<Test>::assimilate_storage(
+		&pallet_evm::GenesisConfig {
+			accounts,
+			precompiles: vec![],
+		},
+		&mut t,
+	)
+	.unwrap();
 	t.into()
 }
 

frame/evm/src/lib.rs

@@ -74,6 +74,8 @@ use frame_support::{
 };
 use frame_system::RawOrigin;
 use impl_trait_for_tuples::impl_for_tuples;
+use scale_codec::{Decode, Encode};
+use scale_info::TypeInfo;
 use sp_core::{Hasher, H160, H256, U256};
 use sp_runtime::{
 	traits::{BadOrigin, Saturating, UniqueSaturatedInto, Zero},
@@ -155,6 +157,9 @@ pub mod pallet {
 		/// Find author for the current block.
 		type FindAuthor: FindAuthor<H160>;
 
+		/// Origin allowed to modify Precompiles
+		type PrecompileModifierOrigin: EnsureOrigin<Self::RuntimeOrigin>;
+
 		/// EVM config used in the module.
 		fn config() -> &'static EvmConfig {
 			&LONDON_CONFIG
@@ -404,6 +409,37 @@ pub mod pallet {
 				pays_fee: Pays::No,
 			})
 		}
+
+		/// Add a precompile to storage
+		#[pallet::call_index(4)]
+		#[pallet::weight(T::DbWeight::get().reads_writes(0, 1))]
+		pub fn add_precompile(
+			origin: OriginFor<T>,
+			address: H160,
+			label: PrecompileLabel,
+		) -> DispatchResult {
+			T::PrecompileModifierOrigin::ensure_origin(origin)?;
+
+			Self::do_add_precompile(&address, label);
+
+			Ok(())
+		}
+
+		/// Remove a precompile from storage
+		#[pallet::call_index(5)]
+		#[pallet::weight(T::DbWeight::get().reads_writes(0, 1))]
+		pub fn remove_precompile(origin: OriginFor<T>, address: H160) -> DispatchResult {
+			T::PrecompileModifierOrigin::ensure_origin(origin)?;
+
+			ensure!(
+				Precompiles::<T>::contains_key(address),
+				Error::<T>::PrecompileDoesNotExist
+			);
+
+			Self::do_remove_precompile(&address);
+
+			Ok(())
+		}
 	}
 
 	#[pallet::event]
@@ -445,6 +481,8 @@ pub mod pallet {
 		Reentrancy,
 		/// EIP-3607,
 		TransactionMustComeFromEOA,
+		/// Precompile does not exist in storage
+		PrecompileDoesNotExist,
 	}
 
 	impl<T> From<InvalidEvmTransactionError> for Error<T> {
@@ -467,6 +505,7 @@ pub mod pallet {
 	#[cfg_attr(feature = "std", derive(Default))]
 	pub struct GenesisConfig {
 		pub accounts: std::collections::BTreeMap<H160, GenesisAccount>,
+		pub precompiles: Vec<(H160, PrecompileLabel)>,
 	}
 
 	#[pallet::genesis_build]
@@ -497,6 +536,10 @@ pub mod pallet {
 					<AccountStorages<T>>::insert(address, index, value);
 				}
 			}
+
+			for (address, label) in &self.precompiles {
+				Pallet::<T>::do_add_precompile(address, label.clone());
+			}
 		}
 	}
 
@@ -508,6 +551,23 @@ pub mod pallet {
 	#[pallet::getter(fn account_storages)]
 	pub type AccountStorages<T: Config> =
 		StorageDoubleMap<_, Blake2_128Concat, H160, Blake2_128Concat, H256, H256, ValueQuery>;
+
+	/// Allows for precompiles to have arbitrary addresses, potentially more than one.
+	/// `key`: precompile `H160` address
+	/// `value`: precompile label, e.g.: `PrecompileLabel { label: b"Sha3FIPS256".to_vec() }`
+
+	/// Please note that adding a new precompile label here is not enough to guarantee its execution
+	/// It is also required to list new labels on the implementation of `PrecompileSet::execute()`
+	#[pallet::storage]
+	#[pallet::getter(fn precompiles)]
+	pub type Precompiles<T: Config> =
+		StorageMap<_, Blake2_128Concat, H160, PrecompileLabel, ValueQuery>;
+}
+
+#[derive(Decode, Encode, Default, TypeInfo, Clone, PartialEq, Debug)]
+#[cfg_attr(feature = "std", derive(serde::Serialize, serde::Deserialize))]
+pub struct PrecompileLabel {
+	pub label: Vec<u8>,
 }
 
 /// Type alias for currency balance.
@@ -671,6 +731,16 @@ impl<T: Config> GasWeightMapping for FixedGasWeightMapping<T> {
 static LONDON_CONFIG: EvmConfig = EvmConfig::london();
 
 impl<T: Config> Pallet<T> {
+	/// Add a precompile to storage
+	pub fn do_add_precompile(address: &H160, label: PrecompileLabel) {
+		Precompiles::<T>::set(address, label);
+	}
+
+	/// Remove a precompile from storage
+	pub fn do_remove_precompile(address: &H160) {
+		Precompiles::<T>::remove(address);
+	}
+
 	/// Check whether an account is empty.
 	pub fn is_account_empty(address: &H160) -> bool {
 		let (account, _) = Self::account_basic(address);

frame/evm/src/mock.rs

@@ -152,6 +152,7 @@ impl crate::Config for Test {
 	type OnChargeTransaction = ();
 	type OnCreate = ();
 	type FindAuthor = FindAuthorTruncated;
+	type PrecompileModifierOrigin = frame_system::EnsureRoot<Self::AccountId>;
 }
 
 /// Exemple PrecompileSet with only Identity precompile.

frame/evm/src/tests.rs

@@ -67,6 +67,8 @@ pub fn new_test_ext() -> sp_io::TestExternalities {
 		},
 	);
 
+	let precompiles = vec![];
+
 	pallet_balances::GenesisConfig::<Test> {
 		// Create the block author account with some balance.
 		balances: vec![(
@@ -76,7 +78,14 @@ pub fn new_test_ext() -> sp_io::TestExternalities {
 	}
 	.assimilate_storage(&mut t)
 	.expect("Pallet balances storage can be assimilated");
-	GenesisBuild::<Test>::assimilate_storage(&crate::GenesisConfig { accounts }, &mut t).unwrap();
+	GenesisBuild::<Test>::assimilate_storage(
+		&crate::GenesisConfig {
+			accounts,
+			precompiles,
+		},
+		&mut t,
+	)
+	.unwrap();
 	t.into()
 }
 
@@ -611,3 +620,28 @@ fn eip3607_transaction_from_precompile_should_fail() {
 		}
 	});
 }
+
+#[test]
+fn precompile_storage_works() {
+	new_test_ext().execute_with(|| {
+		let origin = RuntimeOrigin::root();
+		let address = H160::from_low_u64_be(1);
+
+		let mut read_precompile = EVM::precompiles(address);
+		assert_eq!(read_precompile, PrecompileLabel::default());
+
+		let label = PrecompileLabel {
+			label: b"ECRecover".to_vec(),
+		};
+
+		assert_ok!(EVM::add_precompile(origin.clone(), address, label.clone()));
+
+		read_precompile = EVM::precompiles(address);
+		assert_eq!(read_precompile, label);
+
+		assert_ok!(EVM::remove_precompile(origin, address));
+
+		read_precompile = EVM::precompiles(address);
+		assert_eq!(read_precompile, PrecompileLabel::default());
+	});
+}

template/node/Cargo.toml

@@ -77,6 +77,7 @@ fp-dynamic-fee = { workspace = true, features = ["default"] }
 fp-evm = { workspace = true, features = ["default"] }
 fp-rpc = { workspace = true, features = ["default"] }
 frontier-template-runtime = { workspace = true, features = ["default"] }
+pallet-evm = { workspace = true }
 
 [build-dependencies]
 substrate-build-script-utils = { workspace = true }

template/node/src/chain_spec.rs

@@ -13,6 +13,8 @@ use frontier_template_runtime::{
 	AccountId, EnableManualSeal, GenesisConfig, Signature, WASM_BINARY,
 };
 
+use pallet_evm::PrecompileLabel;
+
 // The URL for the telemetry server.
 // const STAGING_TELEMETRY_URL: &str = "wss://telemetry.polkadot.io/submit/";
 
@@ -250,6 +252,52 @@ fn testnet_genesis(
 				);
 				map
 			},
+			precompiles: vec![
+				// Ethereum precompiles :
+				(
+					H160::from_low_u64_be(1),
+					PrecompileLabel {
+						label: b"ECRecover".to_vec(),
+					},
+				),
+				(
+					H160::from_low_u64_be(2),
+					PrecompileLabel {
+						label: b"Sha256".to_vec(),
+					},
+				),
+				(
+					H160::from_low_u64_be(3),
+					PrecompileLabel {
+						label: b"Ripemd160".to_vec(),
+					},
+				),
+				(
+					H160::from_low_u64_be(4),
+					PrecompileLabel {
+						label: b"Identity".to_vec(),
+					},
+				),
+				(
+					H160::from_low_u64_be(5),
+					PrecompileLabel {
+						label: b"Modexp".to_vec(),
+					},
+				),
+				// Non-Frontier specific nor Ethereum precompiles :
+				(
+					H160::from_low_u64_be(1024),
+					PrecompileLabel {
+						label: b"Sha3FIPS256".to_vec(),
+					},
+				),
+				(
+					H160::from_low_u64_be(1025),
+					PrecompileLabel {
+						label: b"Sha3FIPS256".to_vec(),
+					},
+				),
+			],
 		},
 		ethereum: Default::default(),
 		dynamic_fee: Default::default(),

template/runtime/src/lib.rs

@@ -343,6 +343,7 @@ impl pallet_evm::Config for Runtime {
 	type OnChargeTransaction = ();
 	type OnCreate = ();
 	type FindAuthor = FindAuthorTruncated<Aura>;
+	type PrecompileModifierOrigin = frame_system::EnsureRoot<Self::AccountId>;
 }
 
 parameter_types! {