crypto.rs

// Copyright 2017-2019 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/>.

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

use sp_std::hash::Hash;
#[cfg(feature = "full_crypto")]
use sp_std::vec::Vec;
#[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};

use zeroize::Zeroize;
#[doc(hidden)]
pub use sp_std::ops::Deref;
use runtime_interface::pass_by::PassByInner;

/// 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)
	}
}

/// A store for sensitive data.
///
/// Calls `Zeroize::zeroize` upon `Drop`.
#[derive(Clone)]
pub struct Protected<T: Zeroize>(T);

impl<T: Zeroize> AsRef<T> for Protected<T> {
	fn as_ref(&self) -> &T {
		&self.0
	}
}

impl<T: Zeroize> sp_std::ops::Deref for Protected<T> {
	type Target = T;

	fn deref(&self) -> &T {
		&self.0
	}
}

#[cfg(feature = "std")]
impl<T: Zeroize> std::fmt::Debug for Protected<T> {
	fn fmt(&self, fmt: &mut std::fmt::Formatter) -> std::fmt::Result {
		write!(fmt, "<protected>")
	}
}

impl<T: Zeroize> From<T> for Protected<T> {
	fn from(t: T) -> Self {
		Protected(t)
	}
}

impl<T: Zeroize> Zeroize for Protected<T> {
	fn zeroize(&mut self) {
		self.0.zeroize()
	}
}

impl<T: Zeroize> Drop for Protected<T> {
	fn drop(&mut self) {
		self.zeroize()
	}
}

/// 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 {