lib.rs

// This file is part of Substrate.

// Copyright (C) 2017-2020 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 sp_std::ops::Deref;

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

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

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

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

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

use codec::{Encode, Decode};

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

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

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

/// 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,
}

/// 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]) {
		Externalities::clear_prefix(*self, prefix)
	}

	/// 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()
	}

	/// "Commit" all existing operations and get the resulting storage change root.
	/// `parent_hash` is a SCALE encoded hash.
	///
	/// The hashing algorithm is defined by the `Block`.
	///
	/// Returns `Some(Vec<u8>)` which holds the SCALE encoded hash or `None` when
	/// changes trie is disabled.
	fn changes_root(&mut self, parent_hash: &[u8]) -> Option<Vec<u8>> {
		self.storage_changes_root(parent_hash)
			.expect("Invalid `parent_hash` given to `changes_root`.")
	}

	/// Get the next key in storage after the given one in lexicographic order.
	fn next_key(&mut self, key: &[u8]) -> Option<Vec<u8>> {
		self.next_storage_key(&key)
	}

	/// Start a new nested transaction.
	///
	/// This allows to either commit or roll back all changes that are made after this call.
	/// For every transaction there must be a matching call to either `rollback_transaction`
	/// or `commit_transaction`. This is also effective for all values manipulated using the
	/// `DefaultChildStorage` API.
	///
	/// # Warning
	///
	/// This is a low level API that is potentially dangerous as it can easily result
	/// in unbalanced transactions. For example, FRAME users should use high level storage
	/// abstractions.
	fn start_transaction(&mut self) {
		self.storage_start_transaction();
	}

	/// Rollback the last transaction started by `start_transaction`.
	///
	/// Any changes made during that transaction are discarded.
	///
	/// # Panics
	///
	/// Will panic if there is no open transaction.
	fn rollback_transaction(&mut self) {
		self.storage_rollback_transaction()
			.expect("No open transaction that can be rolled back.");
	}

	/// Commit the last transaction started by `start_transaction`.
	///
	/// Any changes made during that transaction are committed.
	///
	/// # Panics
	///
	/// Will panic if there is no open transaction.
	fn commit_transaction(&mut self) {
		self.storage_commit_transaction()
			.expect("No open transaction that can be committed.");