git.delta.rocks / unique-network / refs/commits / dc76967d4780

1// Copyright 2019-2022 Unique Network (Gibraltar) Ltd.2// This file is part of Unique Network.34// Unique Network is free software: you can redistribute it and/or modify5// it under the terms of the GNU General Public License as published by6// the Free Software Foundation, either version 3 of the License, or7// (at your option) any later version.89// Unique Network is distributed in the hope that it will be useful,10// but WITHOUT ANY WARRANTY; without even the implied warranty of11// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the12// GNU General Public License for more details.1314// You should have received a copy of the GNU General Public License15// along with Unique Network. If not, see <http://www.gnu.org/licenses/>.1617#![cfg_attr(not(feature = "std"), no_std)]1819#[cfg(not(feature = "std"))]20extern crate alloc;21#[cfg(not(feature = "std"))]22use alloc::format;23use frame_support::dispatch::Weight;2425use core::marker::PhantomData;26use sp_std::cell::RefCell;2728use codec::Decode;29use frame_support::pallet_prelude::DispatchError;30use frame_support::traits::PalletInfo;31use frame_support::{ensure, sp_runtime::ModuleError};32use up_data_structs::budget;33use pallet_evm::{34	ExitError, ExitRevert, ExitSucceed, GasWeightMapping, PrecompileFailure, PrecompileOutput,35	PrecompileResult, PrecompileHandle,36};37use sp_core::H160;38// #[cfg(feature = "runtime-benchmarks")]39// pub mod benchmarking;4041use evm_coder::{42	abi::{AbiReader, AbiWrite, AbiWriter},43	execution,44	types::{Msg, value},45};4647pub use pallet::*;4849#[frame_support::pallet]50pub mod pallet {51	use super::*;5253	use frame_system::ensure_signed;54	pub use frame_support::dispatch::DispatchResult;55	use frame_system::pallet_prelude::*;5657	/// DispatchError is opaque, but we need to somehow extract correct error in case of OutOfGas failure58	/// So we have this pallet, which defines OutOfGas error, and knews its own id to check if DispatchError59	/// is thrown because of it60	///61	/// These errors shouldn't end in extrinsic results, as they only used in evm execution path62	#[pallet::error]63	pub enum Error<T> {64		OutOfGas,65		OutOfFund,66	}6768	#[pallet::config]69	pub trait Config: frame_system::Config + pallet_evm::Config {}7071	#[pallet::pallet]72	pub struct Pallet<T>(_);7374	#[pallet::call]75	impl<T: Config> Pallet<T> {76		#[pallet::call_index(0)]77		#[pallet::weight(0)]78		pub fn empty_call(origin: OriginFor<T>) -> DispatchResult {79			let _sender = ensure_signed(origin)?;80			Ok(())81		}82	}83}8485// From instabul hardfork configuration: https://github.com/rust-blockchain/evm/blob/fd4fd6acc0ca3208d6770fdb3ba407c94cdf97c6/runtime/src/lib.rs#L28486pub const G_SLOAD_WORD: u64 = 800;87pub const G_SSTORE_WORD: u64 = 20000;8889pub struct GasCallsBudget<'r, T: Config> {90	recorder: &'r SubstrateRecorder<T>,91	gas_per_call: u64,92}93impl<T: Config> budget::Budget for GasCallsBudget<'_, T> {94	fn consume_custom(&self, calls: u32) -> bool {95		let (gas, overflown) = (calls as u64).overflowing_add(self.gas_per_call);96		if overflown {97			return false;98		}99		self.recorder.consume_gas(gas).is_ok()100	}101}102103#[derive(Default)]104pub struct SubstrateRecorder<T: Config> {105	initial_gas: u64,106	gas_limit: RefCell<u64>,107	_phantom: PhantomData<*const T>,108}109110impl<T: Config> SubstrateRecorder<T> {111	pub fn new(gas_limit: u64) -> Self {112		Self {113			initial_gas: gas_limit,114			gas_limit: RefCell::new(gas_limit),115			_phantom: PhantomData,116		}117	}118119	pub fn gas_left(&self) -> u64 {120		*self.gas_limit.borrow()121	}122	pub fn gas_calls_budget(&self, gas_per_call: u64) -> GasCallsBudget<T> {123		GasCallsBudget {124			recorder: self,125			gas_per_call,126		}127	}128	pub fn weight_calls_budget(&self, weight_per_call: Weight) -> GasCallsBudget<T> {129		GasCallsBudget {130			recorder: self,131			gas_per_call: T::GasWeightMapping::weight_to_gas(weight_per_call),132		}133	}134	pub fn consume_sload_sub(&self) -> DispatchResult {135		self.consume_gas_sub(G_SLOAD_WORD)136	}137	pub fn consume_sstores_sub(&self, amount: usize) -> DispatchResult {138		self.consume_gas_sub(G_SSTORE_WORD.saturating_mul(amount as u64))139	}140	pub fn consume_sstore_sub(&self) -> DispatchResult {141		self.consume_gas_sub(G_SSTORE_WORD)142	}143	pub fn consume_gas_sub(&self, gas: u64) -> DispatchResult {144		ensure!(gas != u64::MAX, Error::<T>::OutOfGas);145		let mut gas_limit = self.gas_limit.borrow_mut();146		ensure!(gas <= *gas_limit, Error::<T>::OutOfGas);147		*gas_limit -= gas;148		Ok(())149	}150151	pub fn consume_sload(&self) -> execution::Result<()> {152		self.consume_gas(G_SLOAD_WORD)153	}154	pub fn consume_sstore(&self) -> execution::Result<()> {155		self.consume_gas(G_SSTORE_WORD)156	}157	pub fn consume_gas(&self, gas: u64) -> execution::Result<()> {158		if gas == u64::MAX {159			return Err(execution::Error::Error(ExitError::OutOfGas));160		}161		let mut gas_limit = self.gas_limit.borrow_mut();162		if gas > *gas_limit {163			return Err(execution::Error::Error(ExitError::OutOfGas));164		}165		*gas_limit -= gas;166		Ok(())167	}168	pub fn return_gas(&self, gas: u64) {169		let mut gas_limit = self.gas_limit.borrow_mut();170		*gas_limit += gas;171	}172173	pub fn evm_to_precompile_output(174		self,175		handle: &mut impl PrecompileHandle,176		result: execution::Result<Option<AbiWriter>>,177	) -> Option<PrecompileResult> {178		use evm_coder::execution::Error;179		// We ignore error here, as it should not occur, as we have our own bookkeeping of gas180		let _ = handle.record_cost(self.initial_gas - self.gas_left());181		Some(match result {182			Ok(Some(v)) => Ok(PrecompileOutput {183				exit_status: ExitSucceed::Returned,184				output: v.finish(),185			}),186			Ok(None) => return None,187			Err(Error::Revert(e)) => {188				let mut writer = AbiWriter::new_call(evm_coder::fn_selector!(Error(string)));189				(&e as &str).abi_write(&mut writer);190191				Err(PrecompileFailure::Revert {192					exit_status: ExitRevert::Reverted,193					output: writer.finish(),194				})195			}196			Err(Error::Fatal(f)) => Err(f.into()),197			Err(Error::Error(e)) => Err(e.into()),198		})199	}200}201202pub fn dispatch_to_evm<T: Config>(err: DispatchError) -> execution::Error {203	use evm_coder::execution::Error as ExError;204	match err {205		DispatchError::Module(ModuleError { index, error, .. })206			if index207				== T::PalletInfo::index::<Pallet<T>>()208					.expect("evm-coder-substrate is a pallet, which should be added to runtime")209					as u8 =>210		{211			let mut read = &error as &[u8];212			match Error::<T>::decode(&mut read) {213				Ok(Error::<T>::OutOfGas) => ExError::Error(ExitError::OutOfGas),214				Ok(Error::<T>::OutOfFund) => ExError::Error(ExitError::OutOfFund),215				_ => unreachable!("this pallet only defines two possible errors"),216			}217		}218		DispatchError::Module(ModuleError {219			message: Some(msg), ..220		}) => ExError::Revert(msg.into()),221		DispatchError::Module(ModuleError { index, error, .. }) => {222			ExError::Revert(format!("error {:?} in pallet {}", error, index))223		}224		e => ExError::Revert(format!("substrate error: {:?}", e)),225	}226}227228pub trait WithRecorder<T: Config> {229	fn recorder(&self) -> &SubstrateRecorder<T>;230	fn into_recorder(self) -> SubstrateRecorder<T>;231}232233/// Helper to simplify implementing bridge between evm-coder definitions and pallet-evm234pub fn call<235	T: Config,236	C: evm_coder::Call + evm_coder::Weighted,237	E: evm_coder::Callable<C> + WithRecorder<T>,238	H: PrecompileHandle,239>(240	handle: &mut H,241	mut e: E,242) -> Option<PrecompileResult> {243	let result = call_internal(244		handle.context().caller,245		&mut e,246		handle.context().apparent_value,247		handle.input(),248	);249	e.into_recorder().evm_to_precompile_output(handle, result)250}251252fn call_internal<253	T: Config,254	C: evm_coder::Call + evm_coder::Weighted,255	E: evm_coder::Callable<C> + WithRecorder<T>,256>(257	caller: H160,258	e: &mut E,259	value: value,260	input: &[u8],261) -> execution::Result<Option<AbiWriter>> {262	let (selector, mut reader) = AbiReader::new_call(input)?;263	let call = C::parse(selector, &mut reader)?;264	if call.is_none() {265		let selector = u32::from_be_bytes(selector);266		return Err(format!("unrecognized selector: 0x{selector:0<8x}").into());267	}268	let call = call.unwrap();269270	let dispatch_info = call.weight();271	e.recorder()272		.consume_gas(T::GasWeightMapping::weight_to_gas(dispatch_info.weight))?;273274	match e.call(Msg {275		call,276		caller,277		value,278	}) {279		Ok(v) => {280			let unspent = v.post_info.calc_unspent(&dispatch_info);281			e.recorder()282				.return_gas(T::GasWeightMapping::weight_to_gas(unspent));283			Ok(Some(v.data))284		}285		Err(v) => {286			let unspent = v.post_info.calc_unspent(&dispatch_info);287			e.recorder()288				.return_gas(T::GasWeightMapping::weight_to_gas(unspent));289			Err(v.data)290		}291	}292}