1234567891011121314151617#![cfg_attr(not(feature = "std"), no_std)]1819use core::marker::PhantomData;20use fp_evm::WithdrawReason;21use frame_support::traits::IsSubType;22pub use pallet::*;23use pallet_evm::{EnsureAddressOrigin, account::CrossAccountId};24use sp_core::H160;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}4546pub struct TransactionValidityHack<T: Config>(PhantomData<*const T>);47impl<T: Config> fp_evm::TransactionValidityHack<T::CrossAccountId> for TransactionValidityHack<T> {48 fn who_pays_fee(origin: H160, reason: &WithdrawReason) -> Option<T::CrossAccountId> {49 match reason {50 WithdrawReason::Call { target, input } => {51 let origin_sub = T::CrossAccountId::from_eth(origin);52 T::EvmSponsorshipHandler::get_sponsor(&origin_sub, &(*target, input.clone()))53 }54 _ => None,55 }56 }57}585960pub struct BridgeSponsorshipHandler<T>(PhantomData<T>);61impl<T, C> SponsorshipHandler<T::AccountId, C> for BridgeSponsorshipHandler<T>62where63 T: Config + pallet_evm::Config,64 C: IsSubType<pallet_evm::Call<T>>,65{66 fn get_sponsor(who: &T::AccountId, call: &C) -> Option<T::AccountId> {67 match call.is_sub_type()? {68 pallet_evm::Call::call {69 source,70 target,71 input,72 ..73 } => {74 let _ = T::CallOrigin::ensure_address_origin(75 source,76 <frame_system::RawOrigin<T::AccountId>>::Signed(who.clone()).into(),77 )78 .ok()?;79 let who = T::CrossAccountId::from_sub(who.clone());80 81 82 let sponsor = frame_support::storage::with_transaction(|| {83 TransactionOutcome::Rollback(Ok::<_, DispatchError>(84 T::EvmSponsorshipHandler::get_sponsor(&who, &(*target, input.clone())),85 ))86 })87 88 .ok()??;89 Some(sponsor.as_sub().clone())90 }91 _ => None,92 }93 }94}