lib.rs

// This file is part of Substrate.

// Copyright (C) 2017-2021 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.

//! I/O host interface for substrate runtime.

#![warn(missing_docs)]
#![cfg_attr(not(feature = "std"), no_std)]
#![cfg_attr(not(feature = "std"), feature(alloc_error_handler))]
#![cfg_attr(
	feature = "std",
	doc = "Substrate runtime standard library as compiled when linked with Rust's standard library."
)]
#![cfg_attr(
	not(feature = "std"),
	doc = "Substrate's runtime standard library as compiled without Rust's standard library."
)]

use sp_std::vec::Vec;

#[cfg(feature = "std")]
use tracing;

#[cfg(feature = "std")]
use sp_core::{
	crypto::Pair,
	hexdisplay::HexDisplay,
	offchain::{OffchainDbExt, OffchainWorkerExt, TransactionPoolExt},
	storage::ChildInfo,
	traits::{RuntimeSpawnExt, TaskExecutorExt},
};
#[cfg(feature = "std")]
use sp_keystore::{KeystoreExt, SyncCryptoStore};

use sp_core::{
	crypto::KeyTypeId,
	ecdsa, ed25519,
	offchain::{
		HttpError, HttpRequestId, HttpRequestStatus, OpaqueNetworkState, StorageKind, Timestamp,
	},
	sr25519,
	storage::StateVersion,
	LogLevel, LogLevelFilter, OpaquePeerId, H256,
};

#[cfg(feature = "std")]
use sp_trie::{LayoutV0, LayoutV1, TrieConfiguration};

use sp_runtime_interface::{
	pass_by::{PassBy, PassByCodec},
	runtime_interface, Pointer,
};

use codec::{Decode, Encode};

#[cfg(feature = "std")]
use sp_externalities::{Externalities, ExternalitiesExt};

#[cfg(feature = "std")]
mod batch_verifier;

#[cfg(feature = "std")]
use batch_verifier::BatchVerifier;

#[cfg(feature = "std")]
const LOG_TARGET: &str = "runtime::io";

/// Error verifying ECDSA signature
#[derive(Encode, Decode)]
pub enum EcdsaVerifyError {
	/// Incorrect value of R or S
	BadRS,
	/// Incorrect value of V
	BadV,
	/// Invalid signature
	BadSignature,
}

/// The outcome of calling `storage_kill`. Returned value is the number of storage items
/// removed from the backend from making the `storage_kill` call.
#[derive(PassByCodec, Encode, Decode)]
pub enum KillStorageResult {
	/// All key to remove were removed, return number of key removed from backend.
	AllRemoved(u32),
	/// Not all key to remove were removed, return number of key removed from backend.
	SomeRemaining(u32),
}

/// Interface for accessing the storage from within the runtime.
#[runtime_interface]
pub trait Storage {
	/// Returns the data for `key` in the storage or `None` if the key can not be found.
	fn get(&self, key: &[u8]) -> Option<Vec<u8>> {
		self.storage(key).map(|s| s.to_vec())
	}

	/// Get `key` from storage, placing the value into `value_out` and return the number of
	/// bytes that the entry in storage has beyond the offset or `None` if the storage entry
	/// doesn't exist at all.
	/// If `value_out` length is smaller than the returned length, only `value_out` length bytes
	/// are copied into `value_out`.
	fn read(&self, key: &[u8], value_out: &mut [u8], value_offset: u32) -> Option<u32> {
		self.storage(key).map(|value| {
			let value_offset = value_offset as usize;
			let data = &value[value_offset.min(value.len())..];
			let written = std::cmp::min(data.len(), value_out.len());
			value_out[..written].copy_from_slice(&data[..written]);
			data.len() as u32
		})
	}

	/// Set `key` to `value` in the storage.
	fn set(&mut self, key: &[u8], value: &[u8]) {
		self.set_storage(key.to_vec(), value.to_vec());
	}

	/// Clear the storage of the given `key` and its value.
	fn clear(&mut self, key: &[u8]) {
		self.clear_storage(key)
	}

	/// Check whether the given `key` exists in storage.
	fn exists(&self, key: &[u8]) -> bool {
		self.exists_storage(key)
	}

	/// Clear the storage of each key-value pair where the key starts with the given `prefix`.
	fn clear_prefix(&mut self, prefix: &[u8]) {
		let _ = Externalities::clear_prefix(*self, prefix, None);
	}

	/// Clear the storage of each key-value pair where the key starts with the given `prefix`.
	///
	/// # Limit
	///
	/// Deletes all keys from the overlay and up to `limit` keys from the backend if
	/// it is set to `Some`. No limit is applied when `limit` is set to `None`.
	///
	/// The limit can be used to partially delete a prefix storage in case it is too large
	/// to delete in one go (block).
	///
	/// It returns a boolean false iff some keys are remaining in
	/// the prefix after the functions returns. Also returns a `u32` with
	/// the number of keys removed from the process.
	///
	/// # Note
	///
	/// Please note that keys that are residing in the overlay for that prefix when
	/// issuing this call are all deleted without counting towards the `limit`. Only keys
	/// written during the current block are part of the overlay. Deleting with a `limit`
	/// mostly makes sense with an empty overlay for that prefix.
	///
	/// Calling this function multiple times per block for the same `prefix` does
	/// not make much sense because it is not cumulative when called inside the same block.
	/// Use this function to distribute the deletion of a single child trie across multiple
	/// blocks.
	#[version(2)]
	fn clear_prefix(&mut self, prefix: &[u8], limit: Option<u32>) -> KillStorageResult {
		let (all_removed, num_removed) = Externalities::clear_prefix(*self, prefix, limit);
		match all_removed {
			true => KillStorageResult::AllRemoved(num_removed),
			false => KillStorageResult::SomeRemaining(num_removed),
		}
	}

	/// Append the encoded `value` to the storage item at `key`.
	///
	/// The storage item needs to implement [`EncodeAppend`](codec::EncodeAppend).
	///
	/// # Warning
	///
	/// If the storage item does not support [`EncodeAppend`](codec::EncodeAppend) or
	/// something else fails at appending, the storage item will be set to `[value]`.
	fn append(&mut self, key: &[u8], value: Vec<u8>) {
		self.storage_append(key.to_vec(), value);
	}

	/// "Commit" all existing operations and compute the resulting storage root.
	///
	/// The hashing algorithm is defined by the `Block`.
	///
	/// Returns a `Vec<u8>` that holds the SCALE encoded hash.
	fn root(&mut self) -> Vec<u8> {
		self.storage_root(StateVersion::V0)
	}

	/// "Commit" all existing operations and compute the resulting storage root.