git.delta.rocks / unique-network / refs/commits / 5f2e50bafc58

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)]1819use core::marker::PhantomData;20use fp_evm::WithdrawReason;21use frame_support::traits::{Currency, IsSubType};22pub use pallet::*;23use pallet_evm::{EVMCurrencyAdapter, EnsureAddressOrigin, account::CrossAccountId};24use sp_core::{H160, U256};25use sp_runtime::TransactionOutcome;26use up_sponsorship::SponsorshipHandler;2728#[frame_support::pallet]29pub mod pallet {30	use super::*;3132	use frame_support::traits::Currency;33	use sp_std::vec::Vec;3435	#[pallet::config]36	pub trait Config: frame_system::Config + pallet_evm::account::Config {37		type EvmSponsorshipHandler: SponsorshipHandler<Self::CrossAccountId, (H160, Vec<u8>)>;38		type Currency: Currency<Self::AccountId>;39	}4041	#[pallet::pallet]42	#[pallet::generate_store(pub(super) trait Store)]43	pub struct Pallet<T>(_);44}4546type NegativeImbalanceOf<C, T> =47	<C as Currency<<T as frame_system::Config>::AccountId>>::NegativeImbalance;4849pub struct ChargeEvmLiquidityInfo<T>50where51	T: Config,52	T: pallet_evm::Config,53{54	who: H160,55	negative_imbalance: NegativeImbalanceOf<<T as Config>::Currency, T>,56}5758pub struct TransactionValidityHack<T: Config>(PhantomData<*const T>);59impl<T: Config> fp_evm::TransactionValidityHack<T::CrossAccountId> for TransactionValidityHack<T> {60	fn who_pays_fee(origin: H160, reason: &WithdrawReason) -> Option<T::CrossAccountId> {61		match reason {62			WithdrawReason::Call { target, input } => {63				// This method is only used for checking, we shouldn't touch storage in it64				frame_support::storage::with_transaction(|| {65					let origin_sub = T::CrossAccountId::from_eth(origin);66					TransactionOutcome::Rollback(T::EvmSponsorshipHandler::get_sponsor(67						&origin_sub,68						&(*target, input.clone()),69					))70				})71			}72			_ => None,73		}74	}75}76pub struct OnChargeTransaction<T: Config>(PhantomData<*const T>);77impl<T> pallet_evm::OnChargeEVMTransaction<T> for OnChargeTransaction<T>78where79	T: Config,80	T: pallet_evm::Config,81{82	type LiquidityInfo = Option<ChargeEvmLiquidityInfo<T>>;8384	fn withdraw_fee(85		who: &T::CrossAccountId,86		reason: WithdrawReason,87		fee: U256,88	) -> core::result::Result<Self::LiquidityInfo, pallet_evm::Error<T>> {89		let who_pays_fee = if let WithdrawReason::Call { target, input } = &reason {90			T::EvmSponsorshipHandler::get_sponsor(who, &(*target, input.clone()))91				.unwrap_or(who.clone())92		} else {93			who.clone()94		};9596		let negative_imbalance = EVMCurrencyAdapter::<<T as Config>::Currency, ()>::withdraw_fee(97			&who_pays_fee,98			reason,99			fee,100		)?;101102		Ok(negative_imbalance.map(|i| ChargeEvmLiquidityInfo {103			who: who_pays_fee.as_eth().clone(),104			negative_imbalance: i,105		}))106	}107108	fn correct_and_deposit_fee(109		who: &T::CrossAccountId,110		corrected_fee: U256,111		already_withdrawn: Self::LiquidityInfo,112	) {113		<EVMCurrencyAdapter<<T as Config>::Currency, ()> as pallet_evm::OnChargeEVMTransaction<T>>::correct_and_deposit_fee(114			&already_withdrawn.as_ref().map(|e| T::CrossAccountId::from_eth(e.who)).unwrap_or(who.clone()),115			corrected_fee,116			already_withdrawn.map(|e| e.negative_imbalance),117		)118	}119120	fn pay_priority_fee(tip: U256) {121		<EVMCurrencyAdapter<<T as Config>::Currency, ()> as pallet_evm::OnChargeEVMTransaction<T>>::pay_priority_fee(tip)122	}123}124125/// Implements sponsoring for evm calls performed from pallet-evm (via api.tx.ethereum.transact/api.tx.evm.call)126pub struct BridgeSponsorshipHandler<T>(PhantomData<T>);127impl<T, C> SponsorshipHandler<T::AccountId, C> for BridgeSponsorshipHandler<T>128where129	T: Config + pallet_evm::Config,130	C: IsSubType<pallet_evm::Call<T>>,131{132	fn get_sponsor(who: &T::AccountId, call: &C) -> Option<T::AccountId> {133		match call.is_sub_type()? {134			pallet_evm::Call::call {135				source,136				target,137				input,138				..139			} => {140				let _ = T::CallOrigin::ensure_address_origin(141					source,142					<frame_system::RawOrigin<T::AccountId>>::Signed(who.clone()).into(),143				)144				.ok()?;145				let who = T::CrossAccountId::from_sub(who.clone());146				// Effects from EvmSponsorshipHandler are applied in OnChargeEvmTransaction by pallet_evm::runner147				// TODO: Should we implement simulation mode (test, but do not apply effects) in `up-sponsorship`?148				let sponsor = frame_support::storage::with_transaction(|| {149					TransactionOutcome::Rollback(T::EvmSponsorshipHandler::get_sponsor(150						&who,151						&(*target, input.clone()),152					))153				})?;154				Some(sponsor.as_sub().clone())155			}156			_ => None,157		}158	}159}