git.delta.rocks / unique-network / refs/commits / d2b5cc3bc7de

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#![doc = include_str!("../README.md")]18#![cfg_attr(not(feature = "std"), no_std)]19#![deny(missing_docs)]2021use core::marker::PhantomData;22use fp_evm::WithdrawReason;23use frame_support::traits::IsSubType;24pub use pallet::*;25use pallet_evm::{EnsureAddressOrigin, account::CrossAccountId};26use sp_core::H160;27use sp_runtime::{TransactionOutcome, DispatchError};28use up_sponsorship::SponsorshipHandler;2930#[frame_support::pallet]31pub mod pallet {32	use super::*;3334	use sp_std::vec::Vec;3536	#[pallet::config]37	pub trait Config: frame_system::Config + pallet_evm::account::Config {38		/// Loosly-coupled handlers for evm call sponsoring39		type EvmSponsorshipHandler: SponsorshipHandler<Self::CrossAccountId, (H160, Vec<u8>)>;40	}4142	#[pallet::pallet]43	#[pallet::generate_store(pub(super) trait Store)]44	pub struct Pallet<T>(_);45}4647/// Implements [`fp_evm::TransactionValidityHack`], which provides sponsor address to pallet-evm48pub struct TransactionValidityHack<T: Config>(PhantomData<*const T>);49impl<T: Config> fp_evm::TransactionValidityHack<T::CrossAccountId> for TransactionValidityHack<T> {50	fn who_pays_fee(origin: H160, reason: &WithdrawReason) -> Option<T::CrossAccountId> {51		match reason {52			WithdrawReason::Call { target, input } => {53				let origin_sub = T::CrossAccountId::from_eth(origin);54				T::EvmSponsorshipHandler::get_sponsor(&origin_sub, &(*target, input.clone()))55			}56			_ => None,57		}58	}59}6061/// Implements sponsoring for evm calls performed from pallet-evm (via api.tx.ethereum.transact/api.tx.evm.call)62pub struct BridgeSponsorshipHandler<T>(PhantomData<T>);63impl<T, C> SponsorshipHandler<T::AccountId, C> for BridgeSponsorshipHandler<T>64where65	T: Config + pallet_evm::Config,66	C: IsSubType<pallet_evm::Call<T>>,67{68	fn get_sponsor(who: &T::AccountId, call: &C) -> Option<T::AccountId> {69		match call.is_sub_type()? {70			pallet_evm::Call::call {71				source,72				target,73				input,74				..75			} => {76				let _ = T::CallOrigin::ensure_address_origin(77					source,78					<frame_system::RawOrigin<T::AccountId>>::Signed(who.clone()).into(),79				)80				.ok()?;81				let who = T::CrossAccountId::from_sub(who.clone());82				// Effects from EvmSponsorshipHandler are applied by pallet_evm::runner83				// TODO: Should we implement simulation mode (test, but do not apply effects) in `up-sponsorship`?84				let sponsor = frame_support::storage::with_transaction(|| {85					TransactionOutcome::Rollback(Ok::<_, DispatchError>(86						T::EvmSponsorshipHandler::get_sponsor(&who, &(*target, input.clone())),87					))88				})89				// FIXME: it may fail with DispatchError in case of depth limit90				.ok()??;91				Some(sponsor.as_sub().clone())92			}93			_ => None,94		}95	}96}