lib.rs

/// Return type of private helper functions.
struct InternalOutput<T: Config, O> {
	/// The gas meter that was used to execute the call.
	gas_meter: GasMeter<T>,
	/// The storage deposit used by the call.
	storage_deposit: StorageDeposit<BalanceOf<T>>,
	/// The result of the call.
	result: Result<O, ExecError>,
}

impl<T: Config> Pallet<T> {
	/// Perform a call to a specified contract.
	///
	/// This function is similar to [`Self::call`], but doesn't perform any address lookups
	/// and better suitable for calling directly from Rust.
	///
	/// # Note
	///
	/// `debug` should only ever be set to `true` when executing as an RPC because
	/// it adds allocations and could be abused to drive the runtime into an OOM panic.
	/// If set to `true` it returns additional human readable debugging information.
	///
	/// It returns the execution result and the amount of used weight.
	pub fn bare_call(
		origin: T::AccountId,
		dest: T::AccountId,
		value: BalanceOf<T>,
		gas_limit: Weight,
		storage_deposit_limit: Option<BalanceOf<T>>,
		data: Vec<u8>,
		debug: bool,
		determinism: Determinism,
	) -> ContractExecResult<BalanceOf<T>> {
		let mut debug_message = if debug { Some(DebugBufferVec::<T>::default()) } else { None };
		let output = Self::internal_call(
			origin,
			dest,
			value,
			gas_limit,
			storage_deposit_limit,
			data,
			debug_message.as_mut(),
			determinism,
		);
		ContractExecResult {
			result: output.result.map_err(|r| r.error),
			gas_consumed: output.gas_meter.gas_consumed(),
			gas_required: output.gas_meter.gas_required(),
			storage_deposit: output.storage_deposit,
			debug_message: debug_message.unwrap_or_default().to_vec(),
		}
	}

	/// Instantiate a new contract.
	///
	/// This function is similar to [`Self::instantiate`], but doesn't perform any address lookups
	/// and better suitable for calling directly from Rust.
	///
	/// It returns the execution result, account id and the amount of used weight.
	///
	/// # Note
	///
	/// `debug` should only ever be set to `true` when executing as an RPC because
	/// it adds allocations and could be abused to drive the runtime into an OOM panic.
	/// If set to `true` it returns additional human readable debugging information.
	pub fn bare_instantiate(
		origin: T::AccountId,
		value: BalanceOf<T>,
		gas_limit: Weight,
		storage_deposit_limit: Option<BalanceOf<T>>,
		code: Code<CodeHash<T>>,
		data: Vec<u8>,
		salt: Vec<u8>,
		debug: bool,
	) -> ContractInstantiateResult<T::AccountId, BalanceOf<T>> {
		let mut debug_message = if debug { Some(DebugBufferVec::<T>::default()) } else { None };
		let output = Self::internal_instantiate(
			origin,
			value,
			gas_limit,
			storage_deposit_limit,
			code,
			data,
			salt,
			debug_message.as_mut(),
		);
		ContractInstantiateResult {
			result: output
				.result
				.map(|(account_id, result)| InstantiateReturnValue { result, account_id })
				.map_err(|e| e.error),
			gas_consumed: output.gas_meter.gas_consumed(),
			gas_required: output.gas_meter.gas_required(),
			storage_deposit: output.storage_deposit,
			debug_message: debug_message.unwrap_or_default().to_vec(),
		}
	}

	/// Upload new code without instantiating a contract from it.
	///
	/// This function is similar to [`Self::upload_code`], but doesn't perform any address lookups
	/// and better suitable for calling directly from Rust.
	pub fn bare_upload_code(
		origin: T::AccountId,
		code: Vec<u8>,
		storage_deposit_limit: Option<BalanceOf<T>>,
		determinism: Determinism,
	) -> CodeUploadResult<CodeHash<T>, BalanceOf<T>> {
		let schedule = T::Schedule::get();
		let module = PrefabWasmModule::from_code(
			code,
			&schedule,
			origin,
			determinism,
			TryInstantiate::Instantiate,
		)
		.map_err(|(err, _)| err)?;
		let deposit = module.open_deposit();
		if let Some(storage_deposit_limit) = storage_deposit_limit {
			ensure!(storage_deposit_limit >= deposit, <Error<T>>::StorageDepositLimitExhausted);
		}
		let result = CodeUploadReturnValue { code_hash: *module.code_hash(), deposit };
		module.store()?;
		Ok(result)
	}

	/// Query storage of a specified contract under a specified key.
	pub fn get_storage(address: T::AccountId, key: Vec<u8>) -> GetStorageResult {
		let contract_info =
			ContractInfoOf::<T>::get(&address).ok_or(ContractAccessError::DoesntExist)?;

		let maybe_value = Storage::<T>::read(
			&contract_info.trie_id,
			&StorageKey::<T>::try_from(key).map_err(|_| ContractAccessError::KeyDecodingFailed)?,
		);
		Ok(maybe_value)
	}

	/// Determine the address of a contract.
	///
	/// This is the address generation function used by contract instantiation. See
	/// [`DefaultAddressGenerator`] for the default implementation.
	pub fn contract_address(
		deploying_address: &T::AccountId,
		code_hash: &CodeHash<T>,
		input_data: &[u8],
		salt: &[u8],
	) -> T::AccountId {
		T::AddressGenerator::generate_address(deploying_address, code_hash, input_data, salt)
	}

	/// Returns the code hash of the contract specified by `account` ID.
	pub fn code_hash(account: &AccountIdOf<T>) -> Option<CodeHash<T>> {
		Storage::<T>::code_hash(account)
	}

	/// Store code for benchmarks which does not check nor instrument the code.
	#[cfg(feature = "runtime-benchmarks")]
	fn store_code_raw(
		code: Vec<u8>,
		owner: T::AccountId,
	) -> frame_support::dispatch::DispatchResult {
		let schedule = T::Schedule::get();
		PrefabWasmModule::store_code_unchecked(code, &schedule, owner)?;
		Ok(())
	}

	/// This exists so that benchmarks can determine the weight of running an instrumentation.
	#[cfg(feature = "runtime-benchmarks")]
	fn reinstrument_module(
		module: &mut PrefabWasmModule<T>,
		schedule: &Schedule<T>,
	) -> frame_support::dispatch::DispatchResult {
		self::wasm::reinstrument(module, schedule).map(|_| ())
	}

	/// Internal function that does the actual call.
	///
	/// Called by dispatchables and public functions.
	fn internal_call(
		origin: T::AccountId,
		dest: T::AccountId,
		value: BalanceOf<T>,
		gas_limit: Weight,
		storage_deposit_limit: Option<BalanceOf<T>>,
		data: Vec<u8>,
		debug_message: Option<&mut DebugBufferVec<T>>,
		determinism: Determinism,
	) -> InternalCallOutput<T> {
		let mut gas_meter = GasMeter::new(gas_limit);
		let mut storage_meter = match StorageMeter::new(&origin, storage_deposit_limit, value) {
			Ok(meter) => meter,
			Err(err) =>
				return InternalCallOutput {
					result: Err(err.into()),
					gas_meter,
					storage_deposit: Default::default(),
				},
		};
		let schedule = T::Schedule::get();
		let result = ExecStack::<T, PrefabWasmModule<T>>::run_call(
			origin.clone(),
			dest,
			&mut gas_meter,
			&mut storage_meter,
			&schedule,
			value,
			data,
			debug_message,
			determinism,
		);
		InternalCallOutput {
			result,
			gas_meter,
			storage_deposit: storage_meter.into_deposit(&origin),
		}
	}

	/// Internal function that does the actual instantiation.
	///
	/// Called by dispatchables and public functions.
	fn internal_instantiate(
		origin: T::AccountId,
		value: BalanceOf<T>,
		gas_limit: Weight,
		storage_deposit_limit: Option<BalanceOf<T>>,
		code: Code<CodeHash<T>>,
		data: Vec<u8>,
		salt: Vec<u8>,
		mut debug_message: Option<&mut DebugBufferVec<T>>,
	) -> InternalInstantiateOutput<T> {
		let mut storage_deposit = Default::default();
		let mut gas_meter = GasMeter::new(gas_limit);
		let try_exec = || {
			let schedule = T::Schedule::get();
			let (extra_deposit, executable) = match code {
				Code::Upload(binary) => {
					let executable = PrefabWasmModule::from_code(
						binary,
						&schedule,
						origin.clone(),
						Determinism::Deterministic,
						TryInstantiate::Skip,
					)
					.map_err(|(err, msg)| {
						debug_message.as_mut().map(|buffer| buffer.try_extend(&mut msg.bytes()));
						err
					})?;
					// The open deposit will be charged during execution when the
					// uploaded module does not already exist. This deposit is not part of the
					// storage meter because it is not transferred to the contract but
					// reserved on the uploading account.
					(executable.open_deposit(), executable)
				},
				Code::Existing(hash) => (
					Default::default(),
					PrefabWasmModule::from_storage(hash, &schedule, &mut gas_meter)?,
				),
			};
			let mut storage_meter = StorageMeter::new(
				&origin,
				storage_deposit_limit,
				value.saturating_add(extra_deposit),
			)?;
			let result = ExecStack::<T, PrefabWasmModule<T>>::run_instantiate(
				origin.clone(),
				executable,
				&mut gas_meter,
				&mut storage_meter,
				&schedule,
				value,
				data,
				&salt,
				debug_message,
			);
			storage_deposit = storage_meter
				.into_deposit(&origin)
				.saturating_add(&StorageDeposit::Charge(extra_deposit));
			result
		};
		InternalInstantiateOutput { result: try_exec(), gas_meter, storage_deposit }
	}

	/// Deposit a pallet contracts event. Handles the conversion to the overarching event type.
	fn deposit_event(topics: Vec<T::Hash>, event: Event<T>) {
		<frame_system::Pallet<T>>::deposit_event_indexed(
			&topics,
			<T as Config>::RuntimeEvent::from(event).into(),
		)
	}

	/// Return the existential deposit of [`Config::Currency`].
	fn min_balance() -> BalanceOf<T> {
		<T::Currency as Inspect<AccountIdOf<T>>>::minimum_balance()
	}

	/// Convert gas_limit from 1D Weight to a 2D Weight.
	///
	/// Used by backwards compatible extrinsics. We cannot just set the proof_size weight limit to
	/// zero or an old `Call` will just fail with OutOfGas.
	fn compat_weight_limit(gas_limit: OldWeight) -> Weight {
		Weight::from_parts(gas_limit.0, u64::from(T::MaxCodeLen::get()) * 2)
	}
}

sp_api::decl_runtime_apis! {
	/// The API used to dry-run contract interactions.
	#[api_version(2)]
	pub trait ContractsApi<AccountId, Balance, BlockNumber, Hash> where
		AccountId: Codec,
		Balance: Codec,
		BlockNumber: Codec,
		Hash: Codec,
	{
		/// Perform a call from a specified account to a given contract.
		///
		/// See [`crate::Pallet::bare_call`].
		fn call(
			origin: AccountId,
			dest: AccountId,
			value: Balance,
			gas_limit: Option<Weight>,
			storage_deposit_limit: Option<Balance>,
			input_data: Vec<u8>,
		) -> ContractExecResult<Balance>;

		/// Instantiate a new contract.
		///
		/// See `[crate::Pallet::bare_instantiate]`.
		fn instantiate(
			origin: AccountId,
			value: Balance,
			gas_limit: Option<Weight>,
			storage_deposit_limit: Option<Balance>,
			code: Code<Hash>,
			data: Vec<u8>,
			salt: Vec<u8>,
		) -> ContractInstantiateResult<AccountId, Balance>;


		/// Upload new code without instantiating a contract from it.
		///
		/// See [`crate::Pallet::bare_upload_code`].
		fn upload_code(
			origin: AccountId,
			code: Vec<u8>,
			storage_deposit_limit: Option<Balance>,
			determinism: Determinism,
		) -> CodeUploadResult<Hash, Balance>;

		/// Query a given storage key in a given contract.
		///
		/// Returns `Ok(Some(Vec<u8>))` if the storage value exists under the given key in the
		/// specified account and `Ok(None)` if it doesn't. If the account specified by the address
		/// doesn't exist, or doesn't have a contract then `Err` is returned.
		fn get_storage(
			address: AccountId,
			key: Vec<u8>,
		) -> GetStorageResult;
	}
}