lib.rs

// This file is part of Substrate.

// Copyright (C) Parity Technologies (UK) Ltd.
// SPDX-License-Identifier: Apache-2.0

// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// 	http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

//! # System Pallet
//!
//! The System pallet provides low-level access to core types and cross-cutting utilities. It acts
//! as the base layer for other pallets to interact with the Substrate framework components.
//!
//! - [`Config`]
//!
//! ## Overview
//!
//! The System pallet defines the core data types used in a Substrate runtime. It also provides
//! several utility functions (see [`Pallet`]) for other FRAME pallets.
//!
//! In addition, it manages the storage items for extrinsic data, indices, event records, and digest
//! items, among other things that support the execution of the current block.
//!
//! It also handles low-level tasks like depositing logs, basic set up and take down of temporary
//! storage entries, and access to previous block hashes.
//!
//! ## Interface
//!
//! ### Dispatchable Functions
//!
//! The System pallet provides dispatchable functions that, with the exception of `remark`, manage
//! low-level or privileged functionality of a Substrate-based runtime.
//!
//! - `remark`: Make some on-chain remark.
//! - `set_heap_pages`: Set the number of pages in the WebAssembly environment's heap.
//! - `set_code`: Set the new runtime code.
//! - `set_code_without_checks`: Set the new runtime code without any checks.
//! - `set_storage`: Set some items of storage.
//! - `kill_storage`: Kill some items from storage.
//! - `kill_prefix`: Kill all storage items with a key that starts with the given prefix.
//! - `remark_with_event`: Make some on-chain remark and emit an event.
//! - `do_task`: Do some specified task.
//! - `authorize_upgrade`: Authorize new runtime code.
//! - `authorize_upgrade_without_checks`: Authorize new runtime code and an upgrade sans
//!   verification.
//! - `apply_authorized_upgrade`: Provide new, already-authorized runtime code.
//!
//! #### A Note on Upgrades
//!
//! The pallet provides two primary means of upgrading the runtime, a single-phase means using
//! `set_code` and a two-phase means using `authorize_upgrade` followed by
//! `apply_authorized_upgrade`. The first will directly attempt to apply the provided `code`
//! (application may have to be scheduled, depending on the context and implementation of the
//! `OnSetCode` trait).
//!
//! The `authorize_upgrade` route allows the authorization of a runtime's code hash. Once
//! authorized, anyone may upload the correct runtime to apply the code. This pattern is useful when
//! providing the runtime ahead of time may be unwieldy, for example when a large preimage (the
//! code) would need to be stored on-chain or sent over a message transport protocol such as a
//! bridge.
//!
//! The `*_without_checks` variants do not perform any version checks, so using them runs the risk
//! of applying a downgrade or entirely other chain specification. They will still validate that the
//! `code` meets the authorized hash.
//!
//! ### Public Functions
//!
//! See the [`Pallet`] struct for details of publicly available functions.
//!
//! ### Signed Extensions
//!
//! The System pallet defines the following extensions:
//!
//!   - [`CheckWeight`]: Checks the weight and length of the block and ensure that it does not
//!     exceed the limits.
//!   - [`CheckNonce`]: Checks the nonce of the transaction. Contains a single payload of type
//!     `T::Nonce`.
//!   - [`CheckEra`]: Checks the era of the transaction. Contains a single payload of type `Era`.
//!   - [`CheckGenesis`]: Checks the provided genesis hash of the transaction. Must be a part of the
//!     signed payload of the transaction.
//!   - [`CheckSpecVersion`]: Checks that the runtime version is the same as the one used to sign
//!     the transaction.
//!   - [`CheckTxVersion`]: Checks that the transaction version is the same as the one used to sign
//!     the transaction.
//!
//! Look up the runtime aggregator file (e.g. `node/runtime`) to see the full list of signed
//! extensions included in a chain.

#![cfg_attr(not(feature = "std"), no_std)]

use pallet_prelude::{BlockNumberFor, HeaderFor};
#[cfg(feature = "std")]
use serde::Serialize;
use sp_io::hashing::blake2_256;
#[cfg(feature = "runtime-benchmarks")]
use sp_runtime::traits::TrailingZeroInput;
use sp_runtime::{
	generic,
	traits::{
		self, AtLeast32Bit, BadOrigin, BlockNumberProvider, Bounded, CheckEqual, Dispatchable,
		Hash, Header, Lookup, LookupError, MaybeDisplay, MaybeSerializeDeserialize, Member, One,
		Saturating, SimpleBitOps, StaticLookup, Zero,
	},
	transaction_validity::{
		InvalidTransaction, TransactionLongevity, TransactionSource, TransactionValidity,
		ValidTransaction,
	},
	DispatchError, RuntimeDebug,
};
#[cfg(any(feature = "std", test))]
use sp_std::map;
use sp_std::{fmt::Debug, marker::PhantomData, prelude::*};
use sp_version::RuntimeVersion;

use codec::{Decode, Encode, EncodeLike, FullCodec, MaxEncodedLen};
#[cfg(feature = "std")]
use frame_support::traits::BuildGenesisConfig;
use frame_support::{
	dispatch::{
		extract_actual_pays_fee, extract_actual_weight, DispatchClass, DispatchInfo,
		DispatchResult, DispatchResultWithPostInfo, PerDispatchClass, PostDispatchInfo,
	},
	ensure, impl_ensure_origin_with_arg_ignoring_arg,
	migrations::MultiStepMigrator,
	pallet_prelude::Pays,
	storage::{self, StorageStreamIter},
	traits::{
		ConstU32, Contains, EnsureOrigin, EnsureOriginWithArg, Get, HandleLifetime,
		OnKilledAccount, OnNewAccount, OnRuntimeUpgrade, OriginTrait, PalletInfo, SortedMembers,
		StoredMap, TypedGet,
	},
	Parameter,
};
use scale_info::TypeInfo;
use sp_core::storage::well_known_keys;
use sp_weights::{RuntimeDbWeight, Weight};

#[cfg(any(feature = "std", test))]
use sp_io::TestExternalities;

pub mod limits;
#[cfg(test)]
pub(crate) mod mock;

pub mod offchain;

mod extensions;
#[cfg(feature = "std")]
pub mod mocking;
#[cfg(test)]
mod tests;
pub mod weights;

pub mod migrations;

pub use extensions::{
	check_genesis::CheckGenesis, check_mortality::CheckMortality,
	check_non_zero_sender::CheckNonZeroSender, check_nonce::CheckNonce,
	check_spec_version::CheckSpecVersion, check_tx_version::CheckTxVersion,
	check_weight::CheckWeight,
};
// Backward compatible re-export.
pub use extensions::check_mortality::CheckMortality as CheckEra;
pub use frame_support::dispatch::RawOrigin;
use frame_support::traits::{PostInherents, PostTransactions, PreInherents};
pub use weights::WeightInfo;

const LOG_TARGET: &str = "runtime::system";

/// Compute the trie root of a list of extrinsics.
///
/// The merkle proof is using the same trie as runtime state with
/// `state_version` 0.
pub fn extrinsics_root<H: Hash, E: codec::Encode>(extrinsics: &[E]) -> H::Output {
	extrinsics_data_root::<H>(extrinsics.iter().map(codec::Encode::encode).collect())
}

/// Compute the trie root of a list of extrinsics.
///
/// The merkle proof is using the same trie as runtime state with
/// `state_version` 0.
pub fn extrinsics_data_root<H: Hash>(xts: Vec<Vec<u8>>) -> H::Output {
	H::ordered_trie_root(xts, sp_core::storage::StateVersion::V0)
}

/// An object to track the currently used extrinsic weight in a block.
pub type ConsumedWeight = PerDispatchClass<Weight>;

pub use pallet::*;

/// Do something when we should be setting the code.