1#![cfg_attr(not(feature = "std"), no_std)]23use core::marker::PhantomData;4use fp_evm::WithdrawReason;5use frame_support::traits::{Currency, IsSubType};6pub use pallet::*;7use pallet_evm::{EVMCurrencyAdapter, EnsureAddressOrigin};8use sp_core::{H160, U256};9use sp_runtime::TransactionOutcome;10use up_sponsorship::SponsorshipHandler;11use up_evm_mapping::EvmBackwardsAddressMapping;12use pallet_evm::AddressMapping;1314#[frame_support::pallet]15pub mod pallet {16 use super::*;1718 use frame_support::traits::Currency;19 use sp_std::vec::Vec;2021 #[pallet::config]22 pub trait Config: frame_system::Config {23 type EvmSponsorshipHandler: SponsorshipHandler<H160, (H160, Vec<u8>)>;24 type Currency: Currency<Self::AccountId>;25 type EvmBackwardsAddressMapping: EvmBackwardsAddressMapping<Self::AccountId>;26 type EvmAddressMapping: AddressMapping<Self::AccountId>;27 }2829 #[pallet::pallet]30 #[pallet::generate_store(pub(super) trait Store)]31 pub struct Pallet<T>(_);32}3334type NegativeImbalanceOf<C, T> =35 <C as Currency<<T as frame_system::Config>::AccountId>>::NegativeImbalance;3637pub struct ChargeEvmLiquidityInfo<T>38where39 T: Config,40 T: pallet_evm::Config,41{42 who: H160,43 negative_imbalance: NegativeImbalanceOf<<T as Config>::Currency, T>,44}4546pub struct TransactionValidityHack<T: Config>(PhantomData<*const T>);47impl<T: Config> fp_evm::TransactionValidityHack for TransactionValidityHack<T> {48 fn who_pays_fee(origin: H160, reason: &WithdrawReason) -> Option<H160> {49 match reason {50 WithdrawReason::Call { target, input } => {51 52 frame_support::storage::with_transaction(|| {53 TransactionOutcome::Rollback(T::EvmSponsorshipHandler::get_sponsor(54 &origin,55 &(*target, input.clone()),56 ))57 })58 }59 _ => None,60 }61 }62}63pub struct OnChargeTransaction<T: Config>(PhantomData<*const T>);64impl<T> pallet_evm::OnChargeEVMTransaction<T> for OnChargeTransaction<T>65where66 T: Config,67 T: pallet_evm::Config,68{69 type LiquidityInfo = Option<ChargeEvmLiquidityInfo<T>>;7071 fn withdraw_fee(72 who: &H160,73 reason: WithdrawReason,74 fee: U256,75 ) -> core::result::Result<Self::LiquidityInfo, pallet_evm::Error<T>> {76 let mut who_pays_fee = *who;77 if let WithdrawReason::Call { target, input } = &reason {78 who_pays_fee = T::EvmSponsorshipHandler::get_sponsor(who, &(*target, input.clone()))79 .unwrap_or(who_pays_fee);80 }81 let negative_imbalance = EVMCurrencyAdapter::<<T as Config>::Currency, ()>::withdraw_fee(82 &who_pays_fee,83 reason,84 fee,85 )?;86 Ok(negative_imbalance.map(|i| ChargeEvmLiquidityInfo {87 who: who_pays_fee,88 negative_imbalance: i,89 }))90 }9192 fn correct_and_deposit_fee(93 who: &H160,94 corrected_fee: U256,95 already_withdrawn: Self::LiquidityInfo,96 ) {97 <EVMCurrencyAdapter<<T as Config>::Currency, ()> as pallet_evm::OnChargeEVMTransaction<T>>::correct_and_deposit_fee(98 &already_withdrawn.as_ref().map(|e| e.who).unwrap_or(*who),99 corrected_fee,100 already_withdrawn.map(|e| e.negative_imbalance),101 )102 }103104 fn pay_priority_fee(tip: U256) {105 <EVMCurrencyAdapter<<T as Config>::Currency, ()> as pallet_evm::OnChargeEVMTransaction<T>>::pay_priority_fee(tip)106 }107}108109110pub struct BridgeSponsorshipHandler<T>(PhantomData<T>);111impl<T, C> SponsorshipHandler<T::AccountId, C> for BridgeSponsorshipHandler<T>112where113 T: Config + pallet_evm::Config,114 C: IsSubType<pallet_evm::Call<T>>,115{116 fn get_sponsor(who: &T::AccountId, call: &C) -> Option<T::AccountId> {117 match call.is_sub_type()? {118 pallet_evm::Call::call {119 source,120 target,121 input,122 ..123 } => {124 let _ = T::CallOrigin::ensure_address_origin(125 source,126 <frame_system::RawOrigin<T::AccountId>>::Signed(who.clone()).into(),127 )128 .ok()?;129 let who = T::EvmBackwardsAddressMapping::from_account_id(who.clone());130 131 132 let sponsor = frame_support::storage::with_transaction(|| {133 TransactionOutcome::Rollback(T::EvmSponsorshipHandler::get_sponsor(134 &who,135 &(*target, input.clone()),136 ))137 })?;138 let sponsor = T::EvmAddressMapping::into_account_id(sponsor);139 Some(sponsor)140 }141 _ => None,142 }143 }144}