lib.rs

// Copyright 2017-2020 Parity Technologies (UK) Ltd.
// This file is part of Substrate.

// Substrate is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// Substrate is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with Substrate.  If not, see <http://www.gnu.org/licenses/>.

//! 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 sp_core::{
	crypto::Pair,
	traits::{KeystoreExt, CallInWasmExt, TaskExecutorExt},
	offchain::{OffchainExt, TransactionPoolExt},
	hexdisplay::HexDisplay,
	storage::ChildInfo,
};

use sp_core::{
	crypto::KeyTypeId, ed25519, sr25519, 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 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]);
			value.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 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 an `Some(_)` 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)
	}
}

/// Interface for accessing the child storage for default child trie,
/// from within the runtime.
#[runtime_interface]
pub trait DefaultChildStorage {

	/// Get a default child storage value for a given key.
	///
	/// Parameter `storage_key` is the unprefixed location of the root of the child trie in the parent trie.
	/// Result is `None` if the value for `key` in the child storage can not be found.
	fn get(
		&self,
		storage_key: &[u8],
		key: &[u8],
	) -> Option<Vec<u8>> {
		let child_info = ChildInfo::new_default(storage_key);
		self.child_storage(&child_info, key).map(|s| s.to_vec())
	}

	/// Allocation efficient variant of `get`.
	///
	/// Get `key` from child 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,
		storage_key: &[u8],
		key: &[u8],
		value_out: &mut [u8],
		value_offset: u32,
	) -> Option<u32> {
		let child_info = ChildInfo::new_default(storage_key);
		self.child_storage(&child_info, 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]);
				value.len() as u32
			})
	}