[pallet-revive] Add chain ID to config an runtime API (#5807)

This PR adds the EVM chain ID to Config as well as a corresponding
runtime API so contracts can query it.

Related issue: https://github.com/paritytech/revive/issues/44

---------

Signed-off-by: xermicus <cyrill@parity.io>
Co-authored-by: command-bot <>

prdoc/pr_5807.prdoc

+title: "[pallet-revive] last call return data API"
+
+doc:
+  - audience: Runtime Dev
+    description: |
+      This PR adds the EVM chain ID to Config as well as a corresponding runtime API so contracts can query it.
+
+      Related issue: https://github.com/paritytech/revive/issues/44
+
+crates:
+  - name: pallet-revive
+    bump: major
+  - name: pallet-revive-fixtures
+    bump: patch
+  - name: pallet-revive-uapi
+    bump: minor

substrate/bin/node/runtime/src/lib.rs

@@ -49,8 +49,8 @@ use frame_support::{
 			imbalance::ResolveAssetTo, nonfungibles_v2::Inspect, pay::PayAssetFromAccount,
 			GetSalary, PayFromAccount,
 		},
-		AsEnsureOriginWithArg, ConstBool, ConstU128, ConstU16, ConstU32, Contains, Currency,
-		EitherOfDiverse, EnsureOriginWithArg, EqualPrivilegeOnly, Imbalance, InsideBoth,
+		AsEnsureOriginWithArg, ConstBool, ConstU128, ConstU16, ConstU32, ConstU64, Contains,
+		Currency, EitherOfDiverse, EnsureOriginWithArg, EqualPrivilegeOnly, Imbalance, InsideBoth,
 		InstanceFilter, KeyOwnerProofSystem, LinearStoragePrice, LockIdentifier, Nothing,
 		OnUnbalanced, VariantCountOf, WithdrawReasons,
 	},
@@ -1419,6 +1419,7 @@ impl pallet_revive::Config for Runtime {
 	type CodeHashLockupDepositPercent = CodeHashLockupDepositPercent;
 	type Debug = ();
 	type Xcm = ();
+	type ChainId = ConstU64<420_420_420>;
 }
 
 impl pallet_sudo::Config for Runtime {

substrate/frame/revive/fixtures/contracts/chain_id.rs

+// This file is part of Substrate.
+
+// Copyright (C) Parity Technologies (UK) Ltd.
+// SPDX-License-Identifier: Apache-2.0
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#![no_std]
+#![no_main]
+
+extern crate common;
+
+use uapi::{HostFn, HostFnImpl as api, ReturnFlags};
+
+#[no_mangle]
+#[polkavm_derive::polkavm_export]
+pub extern "C" fn deploy() {
+	call()
+}
+
+#[no_mangle]
+#[polkavm_derive::polkavm_export]
+pub extern "C" fn call() {
+	let mut buf = [0; 32];
+	api::chain_id(&mut buf);
+	api::return_value(ReturnFlags::empty(), &buf);
+}

substrate/frame/revive/src/lib.rs

@@ -60,7 +60,7 @@ use frame_support::{
 	ensure,
 	traits::{
 		fungible::{Inspect, Mutate, MutateHold},
-		ConstU32, Contains, EnsureOrigin, Get, Time,
+		ConstU32, ConstU64, Contains, EnsureOrigin, Get, Time,
 	},
 	weights::{Weight, WeightMeter},
 	BoundedVec, RuntimeDebugNoBound,
@@ -293,6 +293,13 @@ pub mod pallet {
 		/// This value is usually higher than [`Self::RuntimeMemory`] to account for the fact
 		/// that validators have to hold all storage items in PvF memory.
 		type PVFMemory: Get<u32>;
+
+		/// The [EIP-155](https://eips.ethereum.org/EIPS/eip-155) chain ID.
+		///
+		/// This is a unique identifier assigned to each blockchain network,
+		/// preventing replay attacks.
+		#[pallet::constant]
+		type ChainId: Get<u64>;
 	}
 
 	/// Container for different types that implement [`DefaultConfig`]` of this pallet.
@@ -365,6 +372,7 @@ pub mod pallet {
 			type Xcm = ();
 			type RuntimeMemory = ConstU32<{ 128 * 1024 * 1024 }>;
 			type PVFMemory = ConstU32<{ 512 * 1024 * 1024 }>;
+			type ChainId = ConstU64<{ 0 }>;
 		}
 	}
 
@@ -919,7 +927,7 @@ pub mod pallet {
 				let contract = if let Some(contract) = contract {
 					contract
 				} else {
-					return Err(<Error<T>>::ContractNotFound.into())
+					return Err(<Error<T>>::ContractNotFound.into());
 				};
 				<ExecStack<T, WasmBlob<T>>>::increment_refcount(code_hash)?;
 				<ExecStack<T, WasmBlob<T>>>::decrement_refcount(contract.code_hash);

substrate/frame/revive/src/tests.rs

@@ -412,6 +412,7 @@ parameter_types! {
 	pub static DepositPerByte: BalanceOf<Test> = 1;
 	pub const DepositPerItem: BalanceOf<Test> = 2;
 	pub static CodeHashLockupDepositPercent: Perbill = Perbill::from_percent(0);
+	pub static ChainId: u64 = 384;
 }
 
 impl Convert<Weight, BalanceOf<Self>> for Test {
@@ -496,6 +497,7 @@ impl Config for Test {
 	type InstantiateOrigin = EnsureAccount<Self, InstantiateAccount>;
 	type CodeHashLockupDepositPercent = CodeHashLockupDepositPercent;
 	type Debug = TestDebug;
+	type ChainId = ChainId;
 }
 
 pub struct ExtBuilder {
@@ -4310,4 +4312,17 @@ mod run_tests {
 			assert_ok!(builder::call(addr).build());
 		});
 	}
+
+	#[test]
+	fn chain_id_works() {
+		let (code, _) = compile_module("chain_id").unwrap();
+
+		ExtBuilder::default().existential_deposit(100).build().execute_with(|| {
+			let _ = <Test as Config>::Currency::set_balance(&ALICE, 1_000_000);
+
+			let chain_id = U256::from(<Test as Config>::ChainId::get());
+			let received = builder::bare_instantiate(Code::Upload(code)).build_and_unwrap_result();
+			assert_eq!(received.result.data, chain_id.encode());
+		});
+	}
 }

substrate/frame/revive/src/wasm/runtime.rs

@@ -468,22 +468,28 @@ impl<T: Config> Token<T> for RuntimeCosts {
 			Terminate(locked_dependencies) => T::WeightInfo::seal_terminate(locked_dependencies),
 			DepositEvent { num_topic, len } => T::WeightInfo::seal_deposit_event(num_topic, len),
 			DebugMessage(len) => T::WeightInfo::seal_debug_message(len),
-			SetStorage { new_bytes, old_bytes } =>
-				cost_storage!(write, seal_set_storage, new_bytes, old_bytes),
+			SetStorage { new_bytes, old_bytes } => {
+				cost_storage!(write, seal_set_storage, new_bytes, old_bytes)
+			},
 			ClearStorage(len) => cost_storage!(write, seal_clear_storage, len),
 			ContainsStorage(len) => cost_storage!(read, seal_contains_storage, len),
 			GetStorage(len) => cost_storage!(read, seal_get_storage, len),
 			TakeStorage(len) => cost_storage!(write, seal_take_storage, len),
-			SetTransientStorage { new_bytes, old_bytes } =>
-				cost_storage!(write_transient, seal_set_transient_storage, new_bytes, old_bytes),
-			ClearTransientStorage(len) =>
-				cost_storage!(write_transient, seal_clear_transient_storage, len),
-			ContainsTransientStorage(len) =>
-				cost_storage!(read_transient, seal_contains_transient_storage, len),
-			GetTransientStorage(len) =>
-				cost_storage!(read_transient, seal_get_transient_storage, len),
-			TakeTransientStorage(len) =>
-				cost_storage!(write_transient, seal_take_transient_storage, len),
+			SetTransientStorage { new_bytes, old_bytes } => {
+				cost_storage!(write_transient, seal_set_transient_storage, new_bytes, old_bytes)
+			},
+			ClearTransientStorage(len) => {
+				cost_storage!(write_transient, seal_clear_transient_storage, len)
+			},
+			ContainsTransientStorage(len) => {
+				cost_storage!(read_transient, seal_contains_transient_storage, len)
+			},
+			GetTransientStorage(len) => {
+				cost_storage!(read_transient, seal_get_transient_storage, len)
+			},
+			TakeTransientStorage(len) => {
+				cost_storage!(write_transient, seal_take_transient_storage, len)
+			},
 			Transfer => T::WeightInfo::seal_transfer(),
 			CallBase => T::WeightInfo::seal_call(0, 0),
 			DelegateCallBase => T::WeightInfo::seal_delegate_call(),
@@ -571,7 +577,7 @@ impl<'a, E: Ext, M: PolkaVmInstance<E::T>> Runtime<'a, E, M> {
 			Ok(Step) => None,
 			Ok(Ecalli(idx)) => {
 				let Some(syscall_symbol) = module.imports().get(idx) else {
-					return Some(Err(<Error<E::T>>::InvalidSyscall.into()))
+					return Some(Err(<Error<E::T>>::InvalidSyscall.into()));
 				};
 				match self.handle_ecall(instance, syscall_symbol.as_bytes(), api_version) {
 					Ok(None) => None,
@@ -679,7 +685,7 @@ impl<'a, E: Ext, M: ?Sized + Memory<E::T>> Runtime<'a, E, M> {
 		create_token: impl FnOnce(u32) -> Option<RuntimeCosts>,
 	) -> Result<(), DispatchError> {
 		if allow_skip && out_ptr == SENTINEL {
-			return Ok(())
+			return Ok(());
 		}
 
 		let len = memory.read_u32(out_len_ptr)?;
@@ -703,7 +709,7 @@ impl<'a, E: Ext, M: ?Sized + Memory<E::T>> Runtime<'a, E, M> {
 		create_token: impl FnOnce(u32) -> Option<RuntimeCosts>,
 	) -> Result<(), DispatchError> {
 		if allow_skip && out_ptr == SENTINEL {
-			return Ok(())
+			return Ok(());
 		}
 
 		let buf_len = buf.len() as u32;
@@ -820,7 +826,7 @@ impl<'a, E: Ext, M: ?Sized + Memory<E::T>> Runtime<'a, E, M> {
 		let max_size = self.ext.max_value_size();
 		let charged = self.charge_gas(costs(value_len, self.ext.max_value_size()))?;
 		if value_len > max_size {
-			return Err(Error::<E::T>::ValueTooLarge.into())
+			return Err(Error::<E::T>::ValueTooLarge.into());
 		}
 		let key = self.decode_key(memory, key_ptr, key_len)?;
 		let value = Some(memory.read(value_ptr, value_len)?);
@@ -1022,7 +1028,7 @@ impl<'a, E: Ext, M: ?Sized + Memory<E::T>> Runtime<'a, E, M> {
 			},
 			CallType::DelegateCall { code_hash_ptr } => {
 				if flags.intersects(CallFlags::ALLOW_REENTRY | CallFlags::READ_ONLY) {
-					return Err(Error::<E::T>::InvalidCallFlags.into())
+					return Err(Error::<E::T>::InvalidCallFlags.into());
 				}
 
 				let code_hash = memory.read_h256(code_hash_ptr)?;
@@ -1037,7 +1043,7 @@ impl<'a, E: Ext, M: ?Sized + Memory<E::T>> Runtime<'a, E, M> {
 				return Err(TrapReason::Return(ReturnData {
 					flags: return_value.flags.bits(),
 					data: return_value.data,
-				}))
+				}));
 			}
 		}
 
@@ -1536,6 +1542,19 @@ pub mod env {
 		)?)
 	}
 
+	/// Returns the chain ID.
+	/// See [`pallet_revive_uapi::HostFn::chain_id`].
+	#[api_version(0)]
+	fn chain_id(&mut self, memory: &mut M, out_ptr: u32) -> Result<(), TrapReason> {
+		Ok(self.write_fixed_sandbox_output(
+			memory,
+			out_ptr,
+			&as_bytes(U256::from(<E::T as Config>::ChainId::get())),
+			false,
+			|_| Some(RuntimeCosts::CopyToContract(32)),
+		)?)
+	}
+
 	/// Stores the value transferred along with this call/instantiate into the supplied buffer.
 	/// See [`pallet_revive_uapi::HostFn::value_transferred`].
 	#[api_version(0)]

substrate/frame/revive/uapi/src/host.rs

@@ -71,6 +71,9 @@ pub trait HostFn: private::Sealed {
 	/// - `output`: A reference to the output data buffer to write the balance.
 	fn balance_of(addr: &[u8; 20], output: &mut [u8; 32]);
 
+	/// Returns the [EIP-155](https://eips.ethereum.org/EIPS/eip-155) chain ID.
+	fn chain_id(output: &mut [u8; 32]);
+
 	/// Stores the current block number of the current contract into the supplied buffer.
 	///
 	/// # Parameters

substrate/frame/revive/uapi/src/host/riscv32.rs

@@ -83,6 +83,7 @@ mod sys {
 		pub fn weight_left(out_ptr: *mut u8, out_len_ptr: *mut u32);
 		pub fn balance(out_ptr: *mut u8);
 		pub fn balance_of(addr_ptr: *const u8, out_ptr: *mut u8);
+		pub fn chain_id(out_ptr: *mut u8);
 		pub fn value_transferred(out_ptr: *mut u8);
 		pub fn now(out_ptr: *mut u8);
 		pub fn minimum_balance(out_ptr: *mut u8);
@@ -447,7 +448,7 @@ impl HostFn for HostFnImpl {
 	}
 
 	impl_wrapper_for! {
-		[u8; 32] => block_number, balance, value_transferred, now, minimum_balance;
+		[u8; 32] => block_number, balance, value_transferred, now, minimum_balance, chain_id;
 		[u8; 20] => address, caller;
 	}