git.delta.rocks / unique-network / refs/commits / 1f6cb5bfa45d

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, DispatchError};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(Ok::<_, DispatchError>(67						T::EvmSponsorshipHandler::get_sponsor(68							&origin_sub,69							&(*target, input.clone()),70						),71					))72				})73				// FIXME: it may fail with DispatchError in case of depth limit74				.ok()?75			}76			_ => None,77		}78	}79}80pub struct OnChargeTransaction<T: Config>(PhantomData<*const T>);81impl<T> pallet_evm::OnChargeEVMTransaction<T> for OnChargeTransaction<T>82where83	T: Config,84	T: pallet_evm::Config,85{86	type LiquidityInfo = Option<ChargeEvmLiquidityInfo<T>>;8788	fn withdraw_fee(89		who: &T::CrossAccountId,90		reason: WithdrawReason,91		fee: U256,92	) -> core::result::Result<Self::LiquidityInfo, pallet_evm::Error<T>> {93		let who_pays_fee = if let WithdrawReason::Call { target, input } = &reason {94			T::EvmSponsorshipHandler::get_sponsor(who, &(*target, input.clone()))95				.unwrap_or(who.clone())96		} else {97			who.clone()98		};99100		let negative_imbalance = EVMCurrencyAdapter::<<T as Config>::Currency, ()>::withdraw_fee(101			&who_pays_fee,102			reason,103			fee,104		)?;105106		Ok(negative_imbalance.map(|i| ChargeEvmLiquidityInfo {107			who: who_pays_fee.as_eth().clone(),108			negative_imbalance: i,109		}))110	}111112	fn correct_and_deposit_fee(113		who: &T::CrossAccountId,114		corrected_fee: U256,115		already_withdrawn: Self::LiquidityInfo,116	) {117		<EVMCurrencyAdapter<<T as Config>::Currency, ()> as pallet_evm::OnChargeEVMTransaction<T>>::correct_and_deposit_fee(118			&already_withdrawn.as_ref().map(|e| T::CrossAccountId::from_eth(e.who)).unwrap_or(who.clone()),119			corrected_fee,120			already_withdrawn.map(|e| e.negative_imbalance),121		)122	}123124	fn pay_priority_fee(tip: U256) {125		<EVMCurrencyAdapter<<T as Config>::Currency, ()> as pallet_evm::OnChargeEVMTransaction<T>>::pay_priority_fee(tip)126	}127}128129/// Implements sponsoring for evm calls performed from pallet-evm (via api.tx.ethereum.transact/api.tx.evm.call)130pub struct BridgeSponsorshipHandler<T>(PhantomData<T>);131impl<T, C> SponsorshipHandler<T::AccountId, C> for BridgeSponsorshipHandler<T>132where133	T: Config + pallet_evm::Config,134	C: IsSubType<pallet_evm::Call<T>>,135{136	fn get_sponsor(who: &T::AccountId, call: &C) -> Option<T::AccountId> {137		match call.is_sub_type()? {138			pallet_evm::Call::call {139				source,140				target,141				input,142				..143			} => {144				let _ = T::CallOrigin::ensure_address_origin(145					source,146					<frame_system::RawOrigin<T::AccountId>>::Signed(who.clone()).into(),147				)148				.ok()?;149				let who = T::CrossAccountId::from_sub(who.clone());150				// Effects from EvmSponsorshipHandler are applied in OnChargeEvmTransaction by pallet_evm::runner151				// TODO: Should we implement simulation mode (test, but do not apply effects) in `up-sponsorship`?152				let sponsor = frame_support::storage::with_transaction(|| {153					TransactionOutcome::Rollback(Ok::<_, DispatchError>(154						T::EvmSponsorshipHandler::get_sponsor(&who, &(*target, input.clone())),155					))156				})157				// FIXME: it may fail with DispatchError in case of depth limit158				.ok()??;159				Some(sponsor.as_sub().clone())160			}161			_ => None,162		}163	}164}