crypto.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.

// tag::description[]
//! Cryptographic utilities.
// end::description[]

use crate::{sr25519, ed25519};
use sp_std::hash::Hash;
use sp_std::vec::Vec;
use sp_std::str;
#[cfg(feature = "std")]
use sp_std::convert::TryInto;
use sp_std::convert::TryFrom;
#[cfg(feature = "std")]
use parking_lot::Mutex;
#[cfg(feature = "std")]
use rand::{RngCore, rngs::OsRng};
use codec::{Encode, Decode};
#[cfg(feature = "std")]
use regex::Regex;
#[cfg(feature = "std")]
use base58::{FromBase58, ToBase58};
#[cfg(feature = "std")]
use crate::hexdisplay::HexDisplay;
#[doc(hidden)]
pub use sp_std::ops::Deref;
use sp_runtime_interface::pass_by::PassByInner;
/// Trait to zeroize a memory buffer.
pub use zeroize::Zeroize;
/// Trait for accessing reference to `SecretString`.
pub use secrecy::ExposeSecret;
/// A store for sensitive data.
#[cfg(feature = "std")]
pub use secrecy::SecretString;

/// The root phrase for our publicly known keys.
pub const DEV_PHRASE: &str = "bottom drive obey lake curtain smoke basket hold race lonely fit walk";

/// The address of the associated root phrase for our publicly known keys.
pub const DEV_ADDRESS: &str = "5DfhGyQdFobKM8NsWvEeAKk5EQQgYe9AydgJ7rMB6E1EqRzV";

/// The infallible type.
#[derive(crate::RuntimeDebug)]
pub enum Infallible {}

/// The length of the junction identifier. Note that this is also referred to as the
/// `CHAIN_CODE_LENGTH` in the context of Schnorrkel.
#[cfg(feature = "full_crypto")]
pub const JUNCTION_ID_LEN: usize = 32;

/// Similar to `From`, except that the onus is on the part of the caller to ensure
/// that data passed in makes sense. Basically, you're not guaranteed to get anything
/// sensible out.
pub trait UncheckedFrom<T> {
	/// Convert from an instance of `T` to Self. This is not guaranteed to be
	/// whatever counts as a valid instance of `T` and it's up to the caller to
	/// ensure that it makes sense.
	fn unchecked_from(t: T) -> Self;
}

/// The counterpart to `UncheckedFrom`.
pub trait UncheckedInto<T> {
	/// The counterpart to `unchecked_from`.
	fn unchecked_into(self) -> T;
}

impl<S, T: UncheckedFrom<S>> UncheckedInto<T> for S {
	fn unchecked_into(self) -> T {
		T::unchecked_from(self)
	}
}

/// An error with the interpretation of a secret.
#[derive(Debug, Clone, PartialEq, Eq)]
#[cfg(feature = "full_crypto")]
pub enum SecretStringError {
	/// The overall format was invalid (e.g. the seed phrase contained symbols).
	InvalidFormat,
	/// The seed phrase provided is not a valid BIP39 phrase.
	InvalidPhrase,
	/// The supplied password was invalid.
	InvalidPassword,
	/// The seed is invalid (bad content).
	InvalidSeed,
	/// The seed has an invalid length.
	InvalidSeedLength,
	/// The derivation path was invalid (e.g. contains soft junctions when they are not supported).
	InvalidPath,
}

/// A since derivation junction description. It is the single parameter used when creating
/// a new secret key from an existing secret key and, in the case of `SoftRaw` and `SoftIndex`
/// a new public key from an existing public key.
#[derive(Copy, Clone, Eq, PartialEq, Hash, Debug, Encode, Decode)]
#[cfg(feature = "full_crypto")]
pub enum DeriveJunction {
	/// Soft (vanilla) derivation. Public keys have a correspondent derivation.
	Soft([u8; JUNCTION_ID_LEN]),
	/// Hard ("hardened") derivation. Public keys do not have a correspondent derivation.
	Hard([u8; JUNCTION_ID_LEN]),
}

#[cfg(feature = "full_crypto")]
impl DeriveJunction {
	/// Consume self to return a soft derive junction with the same chain code.
	pub fn soften(self) -> Self { DeriveJunction::Soft(self.unwrap_inner()) }

	/// Consume self to return a hard derive junction with the same chain code.
	pub fn harden(self) -> Self { DeriveJunction::Hard(self.unwrap_inner()) }

	/// Create a new soft (vanilla) DeriveJunction from a given, encodable, value.
	///
	/// If you need a hard junction, use `hard()`.
	pub fn soft<T: Encode>(index: T) -> Self {
		let mut cc: [u8; JUNCTION_ID_LEN] = Default::default();
		index.using_encoded(|data| if data.len() > JUNCTION_ID_LEN {
			let hash_result = blake2_rfc::blake2b::blake2b(JUNCTION_ID_LEN, &[], data);
			let hash = hash_result.as_bytes();
			cc.copy_from_slice(hash);
		} else {
			cc[0..data.len()].copy_from_slice(data);
		});
		DeriveJunction::Soft(cc)
	}

	/// Create a new hard (hardened) DeriveJunction from a given, encodable, value.
	///
	/// If you need a soft junction, use `soft()`.
	pub fn hard<T: Encode>(index: T) -> Self {
		Self::soft(index).harden()
	}

	/// Consume self to return the chain code.
	pub fn unwrap_inner(self) -> [u8; JUNCTION_ID_LEN] {
		match self {
			DeriveJunction::Hard(c) | DeriveJunction::Soft(c) => c,
		}
	}

	/// Get a reference to the inner junction id.
	pub fn inner(&self) -> &[u8; JUNCTION_ID_LEN] {
		match self {
			DeriveJunction::Hard(ref c) | DeriveJunction::Soft(ref c) => c,
		}
	}

	/// Return `true` if the junction is soft.
	pub fn is_soft(&self) -> bool {
		match *self {
			DeriveJunction::Soft(_) => true,
			_ => false,
		}
	}

	/// Return `true` if the junction is hard.
	pub fn is_hard(&self) -> bool {
		match *self {
			DeriveJunction::Hard(_) => true,
			_ => false,
		}
	}
}

#[cfg(feature = "full_crypto")]
impl<T: AsRef<str>> From<T> for DeriveJunction {
	fn from(j: T) -> DeriveJunction {
		let j = j.as_ref();
		let (code, hard) = if j.starts_with("/") {
			(&j[1..], true)
		} else {
			(j, false)
		};

		let res = if let Ok(n) = str::parse::<u64>(code) {
			// number
			DeriveJunction::soft(n)
		} else {
			// something else
			DeriveJunction::soft(code)
		};

		if hard {
			res.harden()
		} else {
			res