rust-bitcoin-unsafe-fast/bitcoin/src/bip32.rs

1219 lines
46 KiB
Rust

// SPDX-License-Identifier: CC0-1.0
//! BIP32 implementation.
//!
//! Implementation of BIP32 hierarchical deterministic wallets, as defined
//! at <https://github.com/bitcoin/bips/blob/master/bip-0032.mediawiki>.
//!
use core::default::Default;
use core::ops::Index;
use core::str::FromStr;
use core::{fmt, slice};
use hashes::{hash160, hash_newtype, sha512, Hash, HashEngine, Hmac, HmacEngine};
use internals::{impl_array_newtype, write_err};
use io::Write;
use secp256k1::{self, Secp256k1, XOnlyPublicKey};
#[cfg(feature = "serde")]
use serde;
use crate::base58;
use crate::crypto::key::{self, Keypair, PrivateKey, PublicKey};
use crate::internal_macros::impl_bytes_newtype;
use crate::network::Network;
use crate::prelude::*;
/// Version bytes for extended public keys on the Bitcoin network.
const VERSION_BYTES_MAINNET_PUBLIC: [u8; 4] = [0x04, 0x88, 0xB2, 0x1E];
/// Version bytes for extended private keys on the Bitcoin network.
const VERSION_BYTES_MAINNET_PRIVATE: [u8; 4] = [0x04, 0x88, 0xAD, 0xE4];
/// Version bytes for extended public keys on any of the testnet networks.
const VERSION_BYTES_TESTNETS_PUBLIC: [u8; 4] = [0x04, 0x35, 0x87, 0xCF];
/// Version bytes for extended private keys on any of the testnet networks.
const VERSION_BYTES_TESTNETS_PRIVATE: [u8; 4] = [0x04, 0x35, 0x83, 0x94];
/// A chain code
#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub struct ChainCode([u8; 32]);
impl_array_newtype!(ChainCode, u8, 32);
impl_bytes_newtype!(ChainCode, 32);
impl ChainCode {
fn from_hmac(hmac: Hmac<sha512::Hash>) -> Self {
hmac[32..].try_into().expect("half of hmac is guaranteed to be 32 bytes")
}
}
/// A fingerprint
#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Default)]
pub struct Fingerprint([u8; 4]);
impl_array_newtype!(Fingerprint, u8, 4);
impl_bytes_newtype!(Fingerprint, 4);
hash_newtype! {
/// Extended key identifier as defined in BIP-32.
pub struct XKeyIdentifier(hash160::Hash);
}
/// Extended private key
#[derive(Copy, Clone, PartialEq, Eq)]
#[cfg_attr(feature = "std", derive(Debug))]
pub struct Xpriv {
/// The network this key is to be used on
pub network: Network,
/// How many derivations this key is from the master (which is 0)
pub depth: u8,
/// Fingerprint of the parent key (0 for master)
pub parent_fingerprint: Fingerprint,
/// Child number of the key used to derive from parent (0 for master)
pub child_number: ChildNumber,
/// Private key
pub private_key: secp256k1::SecretKey,
/// Chain code
pub chain_code: ChainCode,
}
#[cfg(feature = "serde")]
crate::serde_utils::serde_string_impl!(Xpriv, "a BIP-32 extended private key");
#[cfg(not(feature = "std"))]
impl fmt::Debug for Xpriv {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.debug_struct("Xpriv")
.field("network", &self.network)
.field("depth", &self.depth)
.field("parent_fingerprint", &self.parent_fingerprint)
.field("child_number", &self.child_number)
.field("chain_code", &self.chain_code)
.field("private_key", &"[SecretKey]")
.finish()
}
}
/// Extended public key
#[derive(Copy, Clone, PartialEq, Eq, Debug, PartialOrd, Ord, Hash)]
pub struct Xpub {
/// The network this key is to be used on
pub network: Network,
/// How many derivations this key is from the master (which is 0)
pub depth: u8,
/// Fingerprint of the parent key
pub parent_fingerprint: Fingerprint,
/// Child number of the key used to derive from parent (0 for master)
pub child_number: ChildNumber,
/// Public key
pub public_key: secp256k1::PublicKey,
/// Chain code
pub chain_code: ChainCode,
}
#[cfg(feature = "serde")]
crate::serde_utils::serde_string_impl!(Xpub, "a BIP-32 extended public key");
/// A child number for a derived key
#[derive(Copy, Clone, PartialEq, Eq, Debug, PartialOrd, Ord, Hash)]
pub enum ChildNumber {
/// Non-hardened key
Normal {
/// Key index, within [0, 2^31 - 1]
index: u32,
},
/// Hardened key
Hardened {
/// Key index, within [0, 2^31 - 1]
index: u32,
},
}
impl ChildNumber {
/// Create a [`Normal`] from an index, returns an error if the index is not within
/// [0, 2^31 - 1].
///
/// [`Normal`]: #variant.Normal
pub fn from_normal_idx(index: u32) -> Result<Self, Error> {
if index & (1 << 31) == 0 {
Ok(ChildNumber::Normal { index })
} else {
Err(Error::InvalidChildNumber(index))
}
}
/// Create a [`Hardened`] from an index, returns an error if the index is not within
/// [0, 2^31 - 1].
///
/// [`Hardened`]: #variant.Hardened
pub fn from_hardened_idx(index: u32) -> Result<Self, Error> {
if index & (1 << 31) == 0 {
Ok(ChildNumber::Hardened { index })
} else {
Err(Error::InvalidChildNumber(index))
}
}
/// Returns `true` if the child number is a [`Normal`] value.
///
/// [`Normal`]: #variant.Normal
pub fn is_normal(&self) -> bool { !self.is_hardened() }
/// Returns `true` if the child number is a [`Hardened`] value.
///
/// [`Hardened`]: #variant.Hardened
pub fn is_hardened(&self) -> bool {
match self {
ChildNumber::Hardened { .. } => true,
ChildNumber::Normal { .. } => false,
}
}
/// Returns the child number that is a single increment from this one.
pub fn increment(self) -> Result<ChildNumber, Error> {
match self {
ChildNumber::Normal { index: idx } => ChildNumber::from_normal_idx(idx + 1),
ChildNumber::Hardened { index: idx } => ChildNumber::from_hardened_idx(idx + 1),
}
}
}
impl From<u32> for ChildNumber {
fn from(number: u32) -> Self {
if number & (1 << 31) != 0 {
ChildNumber::Hardened { index: number ^ (1 << 31) }
} else {
ChildNumber::Normal { index: number }
}
}
}
impl From<ChildNumber> for u32 {
fn from(cnum: ChildNumber) -> Self {
match cnum {
ChildNumber::Normal { index } => index,
ChildNumber::Hardened { index } => index | (1 << 31),
}
}
}
impl fmt::Display for ChildNumber {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match *self {
ChildNumber::Hardened { index } => {
fmt::Display::fmt(&index, f)?;
let alt = f.alternate();
f.write_str(if alt { "h" } else { "'" })
}
ChildNumber::Normal { index } => fmt::Display::fmt(&index, f),
}
}
}
impl FromStr for ChildNumber {
type Err = Error;
fn from_str(inp: &str) -> Result<ChildNumber, Error> {
let is_hardened = inp.chars().last().map_or(false, |l| l == '\'' || l == 'h');
Ok(if is_hardened {
ChildNumber::from_hardened_idx(
inp[0..inp.len() - 1].parse().map_err(|_| Error::InvalidChildNumberFormat)?,
)?
} else {
ChildNumber::from_normal_idx(inp.parse().map_err(|_| Error::InvalidChildNumberFormat)?)?
})
}
}
impl AsRef<[ChildNumber]> for ChildNumber {
fn as_ref(&self) -> &[ChildNumber] { slice::from_ref(self) }
}
#[cfg(feature = "serde")]
impl<'de> serde::Deserialize<'de> for ChildNumber {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: serde::Deserializer<'de>,
{
u32::deserialize(deserializer).map(ChildNumber::from)
}
}
#[cfg(feature = "serde")]
impl serde::Serialize for ChildNumber {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: serde::Serializer,
{
u32::from(*self).serialize(serializer)
}
}
/// Trait that allows possibly failable conversion from a type into a
/// derivation path
pub trait IntoDerivationPath {
/// Convers a given type into a [`DerivationPath`] with possible error
fn into_derivation_path(self) -> Result<DerivationPath, Error>;
}
/// A BIP-32 derivation path.
#[derive(Clone, PartialEq, Eq, Ord, PartialOrd, Hash)]
pub struct DerivationPath(Vec<ChildNumber>);
#[cfg(feature = "serde")]
crate::serde_utils::serde_string_impl!(DerivationPath, "a BIP-32 derivation path");
impl<I> Index<I> for DerivationPath
where
Vec<ChildNumber>: Index<I>,
{
type Output = <Vec<ChildNumber> as Index<I>>::Output;
#[inline]
fn index(&self, index: I) -> &Self::Output { &self.0[index] }
}
impl Default for DerivationPath {
fn default() -> DerivationPath { DerivationPath::master() }
}
impl<T> IntoDerivationPath for T
where
T: Into<DerivationPath>,
{
fn into_derivation_path(self) -> Result<DerivationPath, Error> { Ok(self.into()) }
}
impl IntoDerivationPath for String {
fn into_derivation_path(self) -> Result<DerivationPath, Error> { self.parse() }
}
impl<'a> IntoDerivationPath for &'a str {
fn into_derivation_path(self) -> Result<DerivationPath, Error> { self.parse() }
}
impl From<Vec<ChildNumber>> for DerivationPath {
fn from(numbers: Vec<ChildNumber>) -> Self { DerivationPath(numbers) }
}
impl From<DerivationPath> for Vec<ChildNumber> {
fn from(path: DerivationPath) -> Self { path.0 }
}
impl<'a> From<&'a [ChildNumber]> for DerivationPath {
fn from(numbers: &'a [ChildNumber]) -> Self { DerivationPath(numbers.to_vec()) }
}
impl core::iter::FromIterator<ChildNumber> for DerivationPath {
fn from_iter<T>(iter: T) -> Self
where
T: IntoIterator<Item = ChildNumber>,
{
DerivationPath(Vec::from_iter(iter))
}
}
impl<'a> core::iter::IntoIterator for &'a DerivationPath {
type Item = &'a ChildNumber;
type IntoIter = slice::Iter<'a, ChildNumber>;
fn into_iter(self) -> Self::IntoIter { self.0.iter() }
}
impl AsRef<[ChildNumber]> for DerivationPath {
fn as_ref(&self) -> &[ChildNumber] { &self.0 }
}
impl FromStr for DerivationPath {
type Err = Error;
fn from_str(path: &str) -> Result<DerivationPath, Error> {
let mut parts = path.split('/');
// First parts must be `m`.
if parts.next().unwrap() != "m" {
return Err(Error::InvalidDerivationPathFormat);
}
let ret: Result<Vec<ChildNumber>, Error> = parts.map(str::parse).collect();
Ok(DerivationPath(ret?))
}
}
/// An iterator over children of a [DerivationPath].
///
/// It is returned by the methods [DerivationPath::children_from],
/// [DerivationPath::normal_children] and [DerivationPath::hardened_children].
pub struct DerivationPathIterator<'a> {
base: &'a DerivationPath,
next_child: Option<ChildNumber>,
}
impl<'a> DerivationPathIterator<'a> {
/// Start a new [DerivationPathIterator] at the given child.
pub fn start_from(path: &'a DerivationPath, start: ChildNumber) -> DerivationPathIterator<'a> {
DerivationPathIterator { base: path, next_child: Some(start) }
}
}
impl<'a> Iterator for DerivationPathIterator<'a> {
type Item = DerivationPath;
fn next(&mut self) -> Option<Self::Item> {
let ret = self.next_child?;
self.next_child = ret.increment().ok();
Some(self.base.child(ret))
}
}
impl DerivationPath {
/// Returns length of the derivation path
pub fn len(&self) -> usize { self.0.len() }
/// Returns `true` if the derivation path is empty
pub fn is_empty(&self) -> bool { self.0.is_empty() }
/// Returns derivation path for a master key (i.e. empty derivation path)
pub fn master() -> DerivationPath { DerivationPath(vec![]) }
/// Returns whether derivation path represents master key (i.e. it's length
/// is empty). True for `m` path.
pub fn is_master(&self) -> bool { self.0.is_empty() }
/// Create a new [DerivationPath] that is a child of this one.
pub fn child(&self, cn: ChildNumber) -> DerivationPath {
let mut path = self.0.clone();
path.push(cn);
DerivationPath(path)
}
/// Convert into a [DerivationPath] that is a child of this one.
pub fn into_child(self, cn: ChildNumber) -> DerivationPath {
let mut path = self.0;
path.push(cn);
DerivationPath(path)
}
/// Get an [Iterator] over the children of this [DerivationPath]
/// starting with the given [ChildNumber].
pub fn children_from(&self, cn: ChildNumber) -> DerivationPathIterator {
DerivationPathIterator::start_from(self, cn)
}
/// Get an [Iterator] over the unhardened children of this [DerivationPath].
pub fn normal_children(&self) -> DerivationPathIterator {
DerivationPathIterator::start_from(self, ChildNumber::Normal { index: 0 })
}
/// Get an [Iterator] over the hardened children of this [DerivationPath].
pub fn hardened_children(&self) -> DerivationPathIterator {
DerivationPathIterator::start_from(self, ChildNumber::Hardened { index: 0 })
}
/// Concatenate `self` with `path` and return the resulting new path.
///
/// ```
/// use bitcoin::bip32::{DerivationPath, ChildNumber};
/// use std::str::FromStr;
///
/// let base = DerivationPath::from_str("m/42").unwrap();
///
/// let deriv_1 = base.extend(DerivationPath::from_str("m/0/1").unwrap());
/// let deriv_2 = base.extend(&[
/// ChildNumber::from_normal_idx(0).unwrap(),
/// ChildNumber::from_normal_idx(1).unwrap()
/// ]);
///
/// assert_eq!(deriv_1, deriv_2);
/// ```
pub fn extend<T: AsRef<[ChildNumber]>>(&self, path: T) -> DerivationPath {
let mut new_path = self.clone();
new_path.0.extend_from_slice(path.as_ref());
new_path
}
/// Returns the derivation path as a vector of u32 integers.
/// Unhardened elements are copied as is.
/// 0x80000000 is added to the hardened elements.
///
/// ```
/// use bitcoin::bip32::DerivationPath;
/// use std::str::FromStr;
///
/// let path = DerivationPath::from_str("m/84'/0'/0'/0/1").unwrap();
/// const HARDENED: u32 = 0x80000000;
/// assert_eq!(path.to_u32_vec(), vec![84 + HARDENED, HARDENED, HARDENED, 0, 1]);
/// ```
pub fn to_u32_vec(&self) -> Vec<u32> { self.into_iter().map(|&el| el.into()).collect() }
}
impl fmt::Display for DerivationPath {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.write_str("m")?;
for cn in self.0.iter() {
f.write_str("/")?;
fmt::Display::fmt(cn, f)?;
}
Ok(())
}
}
impl fmt::Debug for DerivationPath {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { fmt::Display::fmt(&self, f) }
}
/// Full information on the used extended public key: fingerprint of the
/// master extended public key and a derivation path from it.
pub type KeySource = (Fingerprint, DerivationPath);
/// A BIP32 error
#[derive(Debug, Clone, PartialEq, Eq)]
#[non_exhaustive]
pub enum Error {
/// A pk->pk derivation was attempted on a hardened key
CannotDeriveFromHardenedKey,
/// A secp256k1 error occurred
Secp256k1(secp256k1::Error),
/// A child number was provided that was out of range
InvalidChildNumber(u32),
/// Invalid childnumber format.
InvalidChildNumberFormat,
/// Invalid derivation path format.
InvalidDerivationPathFormat,
/// Unknown version magic bytes
UnknownVersion([u8; 4]),
/// Encoded extended key data has wrong length
WrongExtendedKeyLength(usize),
/// Base58 encoding error
Base58(base58::Error),
/// Hexadecimal decoding error
Hex(hex::HexToArrayError),
/// `PublicKey` hex should be 66 or 130 digits long.
InvalidPublicKeyHexLength(usize),
}
impl fmt::Display for Error {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
use Error::*;
match *self {
CannotDeriveFromHardenedKey =>
f.write_str("cannot derive hardened key from public key"),
Secp256k1(ref e) => write_err!(f, "secp256k1 error"; e),
InvalidChildNumber(ref n) =>
write!(f, "child number {} is invalid (not within [0, 2^31 - 1])", n),
InvalidChildNumberFormat => f.write_str("invalid child number format"),
InvalidDerivationPathFormat => f.write_str("invalid derivation path format"),
UnknownVersion(ref bytes) => write!(f, "unknown version magic bytes: {:?}", bytes),
WrongExtendedKeyLength(ref len) =>
write!(f, "encoded extended key data has wrong length {}", len),
Base58(ref e) => write_err!(f, "base58 encoding error"; e),
Hex(ref e) => write_err!(f, "Hexadecimal decoding error"; e),
InvalidPublicKeyHexLength(got) =>
write!(f, "PublicKey hex should be 66 or 130 digits long, got: {}", got),
}
}
}
#[cfg(feature = "std")]
impl std::error::Error for Error {
fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
use Error::*;
match *self {
Secp256k1(ref e) => Some(e),
Base58(ref e) => Some(e),
Hex(ref e) => Some(e),
CannotDeriveFromHardenedKey
| InvalidChildNumber(_)
| InvalidChildNumberFormat
| InvalidDerivationPathFormat
| UnknownVersion(_)
| WrongExtendedKeyLength(_)
| InvalidPublicKeyHexLength(_) => None,
}
}
}
impl From<key::Error> for Error {
fn from(err: key::Error) -> Self {
match err {
key::Error::Base58(e) => Error::Base58(e),
key::Error::Secp256k1(e) => Error::Secp256k1(e),
key::Error::InvalidKeyPrefix(_) => Error::Secp256k1(secp256k1::Error::InvalidPublicKey),
key::Error::Hex(e) => Error::Hex(e),
key::Error::InvalidHexLength(got) => Error::InvalidPublicKeyHexLength(got),
}
}
}
impl From<secp256k1::Error> for Error {
fn from(e: secp256k1::Error) -> Error { Error::Secp256k1(e) }
}
impl From<base58::Error> for Error {
fn from(err: base58::Error) -> Self { Error::Base58(err) }
}
impl Xpriv {
/// Construct a new master key from a seed value
pub fn new_master(network: Network, seed: &[u8]) -> Result<Xpriv, Error> {
let mut hmac_engine: HmacEngine<sha512::Hash> = HmacEngine::new(b"Bitcoin seed");
hmac_engine.input(seed);
let hmac_result: Hmac<sha512::Hash> = Hmac::from_engine(hmac_engine);
Ok(Xpriv {
network,
depth: 0,
parent_fingerprint: Default::default(),
child_number: ChildNumber::from_normal_idx(0)?,
private_key: secp256k1::SecretKey::from_slice(&hmac_result[..32])?,
chain_code: ChainCode::from_hmac(hmac_result),
})
}
/// Constructs ECDSA compressed private key matching internal secret key representation.
pub fn to_priv(self) -> PrivateKey {
PrivateKey { compressed: true, network: self.network, inner: self.private_key }
}
/// Constructs BIP340 keypair for Schnorr signatures and Taproot use matching the internal
/// secret key representation.
pub fn to_keypair<C: secp256k1::Signing>(self, secp: &Secp256k1<C>) -> Keypair {
Keypair::from_seckey_slice(secp, &self.private_key[..])
.expect("BIP32 internal private key representation is broken")
}
/// Attempts to derive an extended private key from a path.
///
/// The `path` argument can be both of type `DerivationPath` or `Vec<ChildNumber>`.
pub fn derive_priv<C: secp256k1::Signing, P: AsRef<[ChildNumber]>>(
&self,
secp: &Secp256k1<C>,
path: &P,
) -> Result<Xpriv, Error> {
let mut sk: Xpriv = *self;
for cnum in path.as_ref() {
sk = sk.ckd_priv(secp, *cnum)?;
}
Ok(sk)
}
/// Private->Private child key derivation
fn ckd_priv<C: secp256k1::Signing>(
&self,
secp: &Secp256k1<C>,
i: ChildNumber,
) -> Result<Xpriv, Error> {
let mut hmac_engine: HmacEngine<sha512::Hash> = HmacEngine::new(&self.chain_code[..]);
match i {
ChildNumber::Normal { .. } => {
// Non-hardened key: compute public data and use that
hmac_engine.input(
&secp256k1::PublicKey::from_secret_key(secp, &self.private_key).serialize()[..],
);
}
ChildNumber::Hardened { .. } => {
// Hardened key: use only secret data to prevent public derivation
hmac_engine.input(&[0u8]);
hmac_engine.input(&self.private_key[..]);
}
}
hmac_engine.input(&u32::from(i).to_be_bytes());
let hmac_result: Hmac<sha512::Hash> = Hmac::from_engine(hmac_engine);
let sk = secp256k1::SecretKey::from_slice(&hmac_result[..32])
.expect("statistically impossible to hit");
let tweaked =
sk.add_tweak(&self.private_key.into()).expect("statistically impossible to hit");
Ok(Xpriv {
network: self.network,
depth: self.depth + 1,
parent_fingerprint: self.fingerprint(secp),
child_number: i,
private_key: tweaked,
chain_code: ChainCode::from_hmac(hmac_result),
})
}
/// Decoding extended private key from binary data according to BIP 32
pub fn decode(data: &[u8]) -> Result<Xpriv, Error> {
if data.len() != 78 {
return Err(Error::WrongExtendedKeyLength(data.len()));
}
let network = if data.starts_with(&VERSION_BYTES_MAINNET_PRIVATE) {
Network::Bitcoin
} else if data.starts_with(&VERSION_BYTES_TESTNETS_PRIVATE) {
Network::Testnet
} else {
let (b0, b1, b2, b3) = (data[0], data[1], data[2], data[3]);
return Err(Error::UnknownVersion([b0, b1, b2, b3]));
};
Ok(Xpriv {
network,
depth: data[4],
parent_fingerprint: data[5..9]
.try_into()
.expect("9 - 5 == 4, which is the Fingerprint length"),
child_number: u32::from_be_bytes(data[9..13].try_into().expect("4 byte slice")).into(),
chain_code: data[13..45]
.try_into()
.expect("45 - 13 == 32, which is the ChainCode length"),
private_key: secp256k1::SecretKey::from_slice(&data[46..78])?,
})
}
/// Extended private key binary encoding according to BIP 32
pub fn encode(&self) -> [u8; 78] {
let mut ret = [0; 78];
ret[0..4].copy_from_slice(&match self.network {
Network::Bitcoin => VERSION_BYTES_MAINNET_PRIVATE,
Network::Testnet | Network::Signet | Network::Regtest => VERSION_BYTES_TESTNETS_PRIVATE,
});
ret[4] = self.depth;
ret[5..9].copy_from_slice(&self.parent_fingerprint[..]);
ret[9..13].copy_from_slice(&u32::from(self.child_number).to_be_bytes());
ret[13..45].copy_from_slice(&self.chain_code[..]);
ret[45] = 0;
ret[46..78].copy_from_slice(&self.private_key[..]);
ret
}
/// Returns the HASH160 of the public key belonging to the xpriv
pub fn identifier<C: secp256k1::Signing>(&self, secp: &Secp256k1<C>) -> XKeyIdentifier {
Xpub::from_priv(secp, self).identifier()
}
/// Returns the first four bytes of the identifier
pub fn fingerprint<C: secp256k1::Signing>(&self, secp: &Secp256k1<C>) -> Fingerprint {
self.identifier(secp)[0..4].try_into().expect("4 is the fingerprint length")
}
}
impl Xpub {
/// Derives a public key from a private key
pub fn from_priv<C: secp256k1::Signing>(secp: &Secp256k1<C>, sk: &Xpriv) -> Xpub {
Xpub {
network: sk.network,
depth: sk.depth,
parent_fingerprint: sk.parent_fingerprint,
child_number: sk.child_number,
public_key: secp256k1::PublicKey::from_secret_key(secp, &sk.private_key),
chain_code: sk.chain_code,
}
}
/// Constructs ECDSA compressed public key matching internal public key representation.
pub fn to_pub(self) -> PublicKey { PublicKey { compressed: true, inner: self.public_key } }
/// Constructs BIP340 x-only public key for BIP-340 signatures and Taproot use matching
/// the internal public key representation.
pub fn to_x_only_pub(self) -> XOnlyPublicKey { XOnlyPublicKey::from(self.public_key) }
/// Attempts to derive an extended public key from a path.
///
/// The `path` argument can be any type implementing `AsRef<ChildNumber>`, such as `DerivationPath`, for instance.
pub fn derive_pub<C: secp256k1::Verification, P: AsRef<[ChildNumber]>>(
&self,
secp: &Secp256k1<C>,
path: &P,
) -> Result<Xpub, Error> {
let mut pk: Xpub = *self;
for cnum in path.as_ref() {
pk = pk.ckd_pub(secp, *cnum)?
}
Ok(pk)
}
/// Compute the scalar tweak added to this key to get a child key
pub fn ckd_pub_tweak(
&self,
i: ChildNumber,
) -> Result<(secp256k1::SecretKey, ChainCode), Error> {
match i {
ChildNumber::Hardened { .. } => Err(Error::CannotDeriveFromHardenedKey),
ChildNumber::Normal { index: n } => {
let mut hmac_engine: HmacEngine<sha512::Hash> =
HmacEngine::new(&self.chain_code[..]);
hmac_engine.input(&self.public_key.serialize()[..]);
hmac_engine.input(&n.to_be_bytes());
let hmac_result: Hmac<sha512::Hash> = Hmac::from_engine(hmac_engine);
let private_key = secp256k1::SecretKey::from_slice(&hmac_result[..32])?;
let chain_code = ChainCode::from_hmac(hmac_result);
Ok((private_key, chain_code))
}
}
}
/// Public->Public child key derivation
pub fn ckd_pub<C: secp256k1::Verification>(
&self,
secp: &Secp256k1<C>,
i: ChildNumber,
) -> Result<Xpub, Error> {
let (sk, chain_code) = self.ckd_pub_tweak(i)?;
let tweaked = self.public_key.add_exp_tweak(secp, &sk.into())?;
Ok(Xpub {
network: self.network,
depth: self.depth + 1,
parent_fingerprint: self.fingerprint(),
child_number: i,
public_key: tweaked,
chain_code,
})
}
/// Decoding extended public key from binary data according to BIP 32
pub fn decode(data: &[u8]) -> Result<Xpub, Error> {
if data.len() != 78 {
return Err(Error::WrongExtendedKeyLength(data.len()));
}
let network = if data.starts_with(&VERSION_BYTES_MAINNET_PUBLIC) {
Network::Bitcoin
} else if data.starts_with(&VERSION_BYTES_TESTNETS_PUBLIC) {
Network::Testnet
} else {
let (b0, b1, b2, b3) = (data[0], data[1], data[2], data[3]);
return Err(Error::UnknownVersion([b0, b1, b2, b3]));
};
Ok(Xpub {
network,
depth: data[4],
parent_fingerprint: data[5..9]
.try_into()
.expect("9 - 5 == 4, which is the Fingerprint length"),
child_number: u32::from_be_bytes(data[9..13].try_into().expect("4 byte slice")).into(),
chain_code: data[13..45]
.try_into()
.expect("45 - 13 == 32, which is the ChainCode length"),
public_key: secp256k1::PublicKey::from_slice(&data[45..78])?,
})
}
/// Extended public key binary encoding according to BIP 32
pub fn encode(&self) -> [u8; 78] {
let mut ret = [0; 78];
ret[0..4].copy_from_slice(&match self.network {
Network::Bitcoin => VERSION_BYTES_MAINNET_PUBLIC,
Network::Testnet | Network::Signet | Network::Regtest => VERSION_BYTES_TESTNETS_PUBLIC,
});
ret[4] = self.depth;
ret[5..9].copy_from_slice(&self.parent_fingerprint[..]);
ret[9..13].copy_from_slice(&u32::from(self.child_number).to_be_bytes());
ret[13..45].copy_from_slice(&self.chain_code[..]);
ret[45..78].copy_from_slice(&self.public_key.serialize()[..]);
ret
}
/// Returns the HASH160 of the chaincode
pub fn identifier(&self) -> XKeyIdentifier {
let mut engine = XKeyIdentifier::engine();
engine.write_all(&self.public_key.serialize()).expect("engines don't error");
XKeyIdentifier::from_engine(engine)
}
/// Returns the first four bytes of the identifier
pub fn fingerprint(&self) -> Fingerprint {
self.identifier()[0..4].try_into().expect("4 is the fingerprint length")
}
}
impl fmt::Display for Xpriv {
fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
base58::encode_check_to_fmt(fmt, &self.encode()[..])
}
}
impl FromStr for Xpriv {
type Err = Error;
fn from_str(inp: &str) -> Result<Xpriv, Error> {
let data = base58::decode_check(inp)?;
if data.len() != 78 {
return Err(base58::Error::InvalidLength(data.len()).into());
}
Xpriv::decode(&data)
}
}
impl fmt::Display for Xpub {
fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
base58::encode_check_to_fmt(fmt, &self.encode()[..])
}
}
impl FromStr for Xpub {
type Err = Error;
fn from_str(inp: &str) -> Result<Xpub, Error> {
let data = base58::decode_check(inp)?;
if data.len() != 78 {
return Err(base58::Error::InvalidLength(data.len()).into());
}
Xpub::decode(&data)
}
}
impl From<Xpub> for XKeyIdentifier {
fn from(key: Xpub) -> XKeyIdentifier { key.identifier() }
}
impl From<&Xpub> for XKeyIdentifier {
fn from(key: &Xpub) -> XKeyIdentifier { key.identifier() }
}
#[cfg(test)]
mod tests {
use core::str::FromStr;
use hex::test_hex_unwrap as hex;
use secp256k1::{self, Secp256k1};
use super::ChildNumber::{Hardened, Normal};
use super::*;
use crate::network::Network::{self, Bitcoin};
#[test]
fn test_parse_derivation_path() {
assert_eq!(DerivationPath::from_str("42"), Err(Error::InvalidDerivationPathFormat));
assert_eq!(DerivationPath::from_str("n/0'/0"), Err(Error::InvalidDerivationPathFormat));
assert_eq!(DerivationPath::from_str("4/m/5"), Err(Error::InvalidDerivationPathFormat));
assert_eq!(DerivationPath::from_str("m//3/0'"), Err(Error::InvalidChildNumberFormat));
assert_eq!(DerivationPath::from_str("m/0h/0x"), Err(Error::InvalidChildNumberFormat));
assert_eq!(
DerivationPath::from_str("m/2147483648"),
Err(Error::InvalidChildNumber(2147483648))
);
assert_eq!(DerivationPath::master(), DerivationPath::from_str("m").unwrap());
assert_eq!(DerivationPath::master(), DerivationPath::default());
assert_eq!(DerivationPath::from_str("m"), Ok(vec![].into()));
assert_eq!(
DerivationPath::from_str("m/0'"),
Ok(vec![ChildNumber::from_hardened_idx(0).unwrap()].into())
);
assert_eq!(
DerivationPath::from_str("m/0'/1"),
Ok(vec![
ChildNumber::from_hardened_idx(0).unwrap(),
ChildNumber::from_normal_idx(1).unwrap()
]
.into())
);
assert_eq!(
DerivationPath::from_str("m/0h/1/2'"),
Ok(vec![
ChildNumber::from_hardened_idx(0).unwrap(),
ChildNumber::from_normal_idx(1).unwrap(),
ChildNumber::from_hardened_idx(2).unwrap(),
]
.into())
);
assert_eq!(
DerivationPath::from_str("m/0'/1/2h/2"),
Ok(vec![
ChildNumber::from_hardened_idx(0).unwrap(),
ChildNumber::from_normal_idx(1).unwrap(),
ChildNumber::from_hardened_idx(2).unwrap(),
ChildNumber::from_normal_idx(2).unwrap(),
]
.into())
);
assert_eq!(
DerivationPath::from_str("m/0'/1/2'/2/1000000000"),
Ok(vec![
ChildNumber::from_hardened_idx(0).unwrap(),
ChildNumber::from_normal_idx(1).unwrap(),
ChildNumber::from_hardened_idx(2).unwrap(),
ChildNumber::from_normal_idx(2).unwrap(),
ChildNumber::from_normal_idx(1000000000).unwrap(),
]
.into())
);
let s = "m/0'/50/3'/5/545456";
assert_eq!(DerivationPath::from_str(s), s.into_derivation_path());
assert_eq!(DerivationPath::from_str(s), s.to_string().into_derivation_path());
}
#[test]
fn test_derivation_path_conversion_index() {
let path = DerivationPath::from_str("m/0h/1/2'").unwrap();
let numbers: Vec<ChildNumber> = path.clone().into();
let path2: DerivationPath = numbers.into();
assert_eq!(path, path2);
assert_eq!(
&path[..2],
&[ChildNumber::from_hardened_idx(0).unwrap(), ChildNumber::from_normal_idx(1).unwrap()]
);
let indexed: DerivationPath = path[..2].into();
assert_eq!(indexed, DerivationPath::from_str("m/0h/1").unwrap());
assert_eq!(indexed.child(ChildNumber::from_hardened_idx(2).unwrap()), path);
}
fn test_path<C: secp256k1::Signing + secp256k1::Verification>(
secp: &Secp256k1<C>,
network: Network,
seed: &[u8],
path: DerivationPath,
expected_sk: &str,
expected_pk: &str,
) {
let mut sk = Xpriv::new_master(network, seed).unwrap();
let mut pk = Xpub::from_priv(secp, &sk);
// Check derivation convenience method for Xpriv
assert_eq!(&sk.derive_priv(secp, &path).unwrap().to_string()[..], expected_sk);
// Check derivation convenience method for Xpub, should error
// appropriately if any ChildNumber is hardened
if path.0.iter().any(|cnum| cnum.is_hardened()) {
assert_eq!(pk.derive_pub(secp, &path), Err(Error::CannotDeriveFromHardenedKey));
} else {
assert_eq!(&pk.derive_pub(secp, &path).unwrap().to_string()[..], expected_pk);
}
// Derive keys, checking hardened and non-hardened derivation one-by-one
for &num in path.0.iter() {
sk = sk.ckd_priv(secp, num).unwrap();
match num {
Normal { .. } => {
let pk2 = pk.ckd_pub(secp, num).unwrap();
pk = Xpub::from_priv(secp, &sk);
assert_eq!(pk, pk2);
}
Hardened { .. } => {
assert_eq!(pk.ckd_pub(secp, num), Err(Error::CannotDeriveFromHardenedKey));
pk = Xpub::from_priv(secp, &sk);
}
}
}
// Check result against expected base58
assert_eq!(&sk.to_string()[..], expected_sk);
assert_eq!(&pk.to_string()[..], expected_pk);
// Check decoded base58 against result
let decoded_sk = Xpriv::from_str(expected_sk);
let decoded_pk = Xpub::from_str(expected_pk);
assert_eq!(Ok(sk), decoded_sk);
assert_eq!(Ok(pk), decoded_pk);
}
#[test]
fn test_increment() {
let idx = 9345497; // randomly generated, I promise
let cn = ChildNumber::from_normal_idx(idx).unwrap();
assert_eq!(cn.increment().ok(), Some(ChildNumber::from_normal_idx(idx + 1).unwrap()));
let cn = ChildNumber::from_hardened_idx(idx).unwrap();
assert_eq!(cn.increment().ok(), Some(ChildNumber::from_hardened_idx(idx + 1).unwrap()));
let max = (1 << 31) - 1;
let cn = ChildNumber::from_normal_idx(max).unwrap();
assert_eq!(cn.increment().err(), Some(Error::InvalidChildNumber(1 << 31)));
let cn = ChildNumber::from_hardened_idx(max).unwrap();
assert_eq!(cn.increment().err(), Some(Error::InvalidChildNumber(1 << 31)));
let cn = ChildNumber::from_normal_idx(350).unwrap();
let path = DerivationPath::from_str("m/42'").unwrap();
let mut iter = path.children_from(cn);
assert_eq!(iter.next(), Some("m/42'/350".parse().unwrap()));
assert_eq!(iter.next(), Some("m/42'/351".parse().unwrap()));
let path = DerivationPath::from_str("m/42'/350'").unwrap();
let mut iter = path.normal_children();
assert_eq!(iter.next(), Some("m/42'/350'/0".parse().unwrap()));
assert_eq!(iter.next(), Some("m/42'/350'/1".parse().unwrap()));
let path = DerivationPath::from_str("m/42'/350'").unwrap();
let mut iter = path.hardened_children();
assert_eq!(iter.next(), Some("m/42'/350'/0'".parse().unwrap()));
assert_eq!(iter.next(), Some("m/42'/350'/1'".parse().unwrap()));
let cn = ChildNumber::from_hardened_idx(42350).unwrap();
let path = DerivationPath::from_str("m/42'").unwrap();
let mut iter = path.children_from(cn);
assert_eq!(iter.next(), Some("m/42'/42350'".parse().unwrap()));
assert_eq!(iter.next(), Some("m/42'/42351'".parse().unwrap()));
let cn = ChildNumber::from_hardened_idx(max).unwrap();
let path = DerivationPath::from_str("m/42'").unwrap();
let mut iter = path.children_from(cn);
assert!(iter.next().is_some());
assert!(iter.next().is_none());
}
#[test]
fn test_vector_1() {
let secp = Secp256k1::new();
let seed = hex!("000102030405060708090a0b0c0d0e0f");
// m
test_path(&secp, Bitcoin, &seed, "m".parse().unwrap(),
"xprv9s21ZrQH143K3QTDL4LXw2F7HEK3wJUD2nW2nRk4stbPy6cq3jPPqjiChkVvvNKmPGJxWUtg6LnF5kejMRNNU3TGtRBeJgk33yuGBxrMPHi",
"xpub661MyMwAqRbcFtXgS5sYJABqqG9YLmC4Q1Rdap9gSE8NqtwybGhePY2gZ29ESFjqJoCu1Rupje8YtGqsefD265TMg7usUDFdp6W1EGMcet8");
// m/0h
test_path(&secp, Bitcoin, &seed, "m/0h".parse().unwrap(),
"xprv9uHRZZhk6KAJC1avXpDAp4MDc3sQKNxDiPvvkX8Br5ngLNv1TxvUxt4cV1rGL5hj6KCesnDYUhd7oWgT11eZG7XnxHrnYeSvkzY7d2bhkJ7",
"xpub68Gmy5EdvgibQVfPdqkBBCHxA5htiqg55crXYuXoQRKfDBFA1WEjWgP6LHhwBZeNK1VTsfTFUHCdrfp1bgwQ9xv5ski8PX9rL2dZXvgGDnw");
// m/0h/1
test_path(&secp, Bitcoin, &seed, "m/0h/1".parse().unwrap(),
"xprv9wTYmMFdV23N2TdNG573QoEsfRrWKQgWeibmLntzniatZvR9BmLnvSxqu53Kw1UmYPxLgboyZQaXwTCg8MSY3H2EU4pWcQDnRnrVA1xe8fs",
"xpub6ASuArnXKPbfEwhqN6e3mwBcDTgzisQN1wXN9BJcM47sSikHjJf3UFHKkNAWbWMiGj7Wf5uMash7SyYq527Hqck2AxYysAA7xmALppuCkwQ");
// m/0h/1/2h
test_path(&secp, Bitcoin, &seed, "m/0h/1/2h".parse().unwrap(),
"xprv9z4pot5VBttmtdRTWfWQmoH1taj2axGVzFqSb8C9xaxKymcFzXBDptWmT7FwuEzG3ryjH4ktypQSAewRiNMjANTtpgP4mLTj34bhnZX7UiM",
"xpub6D4BDPcP2GT577Vvch3R8wDkScZWzQzMMUm3PWbmWvVJrZwQY4VUNgqFJPMM3No2dFDFGTsxxpG5uJh7n7epu4trkrX7x7DogT5Uv6fcLW5");
// m/0h/1/2h/2
test_path(&secp, Bitcoin, &seed, "m/0h/1/2h/2".parse().unwrap(),
"xprvA2JDeKCSNNZky6uBCviVfJSKyQ1mDYahRjijr5idH2WwLsEd4Hsb2Tyh8RfQMuPh7f7RtyzTtdrbdqqsunu5Mm3wDvUAKRHSC34sJ7in334",
"xpub6FHa3pjLCk84BayeJxFW2SP4XRrFd1JYnxeLeU8EqN3vDfZmbqBqaGJAyiLjTAwm6ZLRQUMv1ZACTj37sR62cfN7fe5JnJ7dh8zL4fiyLHV");
// m/0h/1/2h/2/1000000000
test_path(&secp, Bitcoin, &seed, "m/0h/1/2h/2/1000000000".parse().unwrap(),
"xprvA41z7zogVVwxVSgdKUHDy1SKmdb533PjDz7J6N6mV6uS3ze1ai8FHa8kmHScGpWmj4WggLyQjgPie1rFSruoUihUZREPSL39UNdE3BBDu76",
"xpub6H1LXWLaKsWFhvm6RVpEL9P4KfRZSW7abD2ttkWP3SSQvnyA8FSVqNTEcYFgJS2UaFcxupHiYkro49S8yGasTvXEYBVPamhGW6cFJodrTHy");
}
#[test]
fn test_vector_2() {
let secp = Secp256k1::new();
let seed = hex!("fffcf9f6f3f0edeae7e4e1dedbd8d5d2cfccc9c6c3c0bdbab7b4b1aeaba8a5a29f9c999693908d8a8784817e7b7875726f6c696663605d5a5754514e4b484542");
// m
test_path(&secp, Bitcoin, &seed, "m".parse().unwrap(),
"xprv9s21ZrQH143K31xYSDQpPDxsXRTUcvj2iNHm5NUtrGiGG5e2DtALGdso3pGz6ssrdK4PFmM8NSpSBHNqPqm55Qn3LqFtT2emdEXVYsCzC2U",
"xpub661MyMwAqRbcFW31YEwpkMuc5THy2PSt5bDMsktWQcFF8syAmRUapSCGu8ED9W6oDMSgv6Zz8idoc4a6mr8BDzTJY47LJhkJ8UB7WEGuduB");
// m/0
test_path(&secp, Bitcoin, &seed, "m/0".parse().unwrap(),
"xprv9vHkqa6EV4sPZHYqZznhT2NPtPCjKuDKGY38FBWLvgaDx45zo9WQRUT3dKYnjwih2yJD9mkrocEZXo1ex8G81dwSM1fwqWpWkeS3v86pgKt",
"xpub69H7F5d8KSRgmmdJg2KhpAK8SR3DjMwAdkxj3ZuxV27CprR9LgpeyGmXUbC6wb7ERfvrnKZjXoUmmDznezpbZb7ap6r1D3tgFxHmwMkQTPH");
// m/0/2147483647h
test_path(&secp, Bitcoin, &seed, "m/0/2147483647h".parse().unwrap(),
"xprv9wSp6B7kry3Vj9m1zSnLvN3xH8RdsPP1Mh7fAaR7aRLcQMKTR2vidYEeEg2mUCTAwCd6vnxVrcjfy2kRgVsFawNzmjuHc2YmYRmagcEPdU9",
"xpub6ASAVgeehLbnwdqV6UKMHVzgqAG8Gr6riv3Fxxpj8ksbH9ebxaEyBLZ85ySDhKiLDBrQSARLq1uNRts8RuJiHjaDMBU4Zn9h8LZNnBC5y4a");
// m/0/2147483647h/1
test_path(&secp, Bitcoin, &seed, "m/0/2147483647h/1".parse().unwrap(),
"xprv9zFnWC6h2cLgpmSA46vutJzBcfJ8yaJGg8cX1e5StJh45BBciYTRXSd25UEPVuesF9yog62tGAQtHjXajPPdbRCHuWS6T8XA2ECKADdw4Ef",
"xpub6DF8uhdarytz3FWdA8TvFSvvAh8dP3283MY7p2V4SeE2wyWmG5mg5EwVvmdMVCQcoNJxGoWaU9DCWh89LojfZ537wTfunKau47EL2dhHKon");
// m/0/2147483647h/1/2147483646h
test_path(&secp, Bitcoin, &seed, "m/0/2147483647h/1/2147483646h".parse().unwrap(),
"xprvA1RpRA33e1JQ7ifknakTFpgNXPmW2YvmhqLQYMmrj4xJXXWYpDPS3xz7iAxn8L39njGVyuoseXzU6rcxFLJ8HFsTjSyQbLYnMpCqE2VbFWc",
"xpub6ERApfZwUNrhLCkDtcHTcxd75RbzS1ed54G1LkBUHQVHQKqhMkhgbmJbZRkrgZw4koxb5JaHWkY4ALHY2grBGRjaDMzQLcgJvLJuZZvRcEL");
// m/0/2147483647h/1/2147483646h/2
test_path(&secp, Bitcoin, &seed, "m/0/2147483647h/1/2147483646h/2".parse().unwrap(),
"xprvA2nrNbFZABcdryreWet9Ea4LvTJcGsqrMzxHx98MMrotbir7yrKCEXw7nadnHM8Dq38EGfSh6dqA9QWTyefMLEcBYJUuekgW4BYPJcr9E7j",
"xpub6FnCn6nSzZAw5Tw7cgR9bi15UV96gLZhjDstkXXxvCLsUXBGXPdSnLFbdpq8p9HmGsApME5hQTZ3emM2rnY5agb9rXpVGyy3bdW6EEgAtqt");
}
#[test]
fn test_vector_3() {
let secp = Secp256k1::new();
let seed = hex!("4b381541583be4423346c643850da4b320e46a87ae3d2a4e6da11eba819cd4acba45d239319ac14f863b8d5ab5a0d0c64d2e8a1e7d1457df2e5a3c51c73235be");
// m
test_path(&secp, Bitcoin, &seed, "m".parse().unwrap(),
"xprv9s21ZrQH143K25QhxbucbDDuQ4naNntJRi4KUfWT7xo4EKsHt2QJDu7KXp1A3u7Bi1j8ph3EGsZ9Xvz9dGuVrtHHs7pXeTzjuxBrCmmhgC6",
"xpub661MyMwAqRbcEZVB4dScxMAdx6d4nFc9nvyvH3v4gJL378CSRZiYmhRoP7mBy6gSPSCYk6SzXPTf3ND1cZAceL7SfJ1Z3GC8vBgp2epUt13");
// m/0h
test_path(&secp, Bitcoin, &seed, "m/0h".parse().unwrap(),
"xprv9uPDJpEQgRQfDcW7BkF7eTya6RPxXeJCqCJGHuCJ4GiRVLzkTXBAJMu2qaMWPrS7AANYqdq6vcBcBUdJCVVFceUvJFjaPdGZ2y9WACViL4L",
"xpub68NZiKmJWnxxS6aaHmn81bvJeTESw724CRDs6HbuccFQN9Ku14VQrADWgqbhhTHBaohPX4CjNLf9fq9MYo6oDaPPLPxSb7gwQN3ih19Zm4Y");
}
#[test]
#[cfg(feature = "serde")]
pub fn encode_decode_childnumber() {
serde_round_trip!(ChildNumber::from_normal_idx(0).unwrap());
serde_round_trip!(ChildNumber::from_normal_idx(1).unwrap());
serde_round_trip!(ChildNumber::from_normal_idx((1 << 31) - 1).unwrap());
serde_round_trip!(ChildNumber::from_hardened_idx(0).unwrap());
serde_round_trip!(ChildNumber::from_hardened_idx(1).unwrap());
serde_round_trip!(ChildNumber::from_hardened_idx((1 << 31) - 1).unwrap());
}
#[test]
#[cfg(feature = "serde")]
pub fn encode_fingerprint_chaincode() {
use serde_json;
let fp = Fingerprint::from([1u8, 2, 3, 42]);
#[rustfmt::skip]
let cc = ChainCode::from(
[1u8,2,3,4,5,6,7,8,9,0,1,2,3,4,5,6,7,8,9,0,1,2,3,4,5,6,7,8,9,0,1,2]
);
serde_round_trip!(fp);
serde_round_trip!(cc);
assert_eq!("\"0102032a\"", serde_json::to_string(&fp).unwrap());
assert_eq!(
"\"0102030405060708090001020304050607080900010203040506070809000102\"",
serde_json::to_string(&cc).unwrap()
);
assert_eq!("0102032a", fp.to_string());
assert_eq!(
"0102030405060708090001020304050607080900010203040506070809000102",
cc.to_string()
);
}
#[test]
fn fmt_child_number() {
assert_eq!("000005h", &format!("{:#06}", ChildNumber::from_hardened_idx(5).unwrap()));
assert_eq!("5h", &format!("{:#}", ChildNumber::from_hardened_idx(5).unwrap()));
assert_eq!("000005'", &format!("{:06}", ChildNumber::from_hardened_idx(5).unwrap()));
assert_eq!("5'", &format!("{}", ChildNumber::from_hardened_idx(5).unwrap()));
assert_eq!("42", &format!("{}", ChildNumber::from_normal_idx(42).unwrap()));
assert_eq!("000042", &format!("{:06}", ChildNumber::from_normal_idx(42).unwrap()));
}
#[test]
#[should_panic(expected = "Secp256k1(InvalidSecretKey)")]
fn schnorr_broken_privkey_zeros() {
/* this is how we generate key:
let mut sk = secp256k1::key::ONE_KEY;
let zeros = [0u8; 32];
unsafe {
sk.as_mut_ptr().copy_from(zeros.as_ptr(), 32);
}
let xpriv = Xpriv {
network: Network::Bitcoin,
depth: 0,
parent_fingerprint: Default::default(),
child_number: ChildNumber::Normal { index: 0 },
private_key: sk,
chain_code: ChainCode::from([0u8; 32])
};
println!("{}", xpriv);
*/
// Xpriv having secret key set to all zeros
let xpriv_str = "xprv9s21ZrQH143K24Mfq5zL5MhWK9hUhhGbd45hLXo2Pq2oqzMMo63oStZzF93Y5wvzdUayhgkkFoicQZcP3y52uPPxFnfoLZB21Teqt1VvEHx";
Xpriv::from_str(xpriv_str).unwrap();
}
#[test]
#[should_panic(expected = "Secp256k1(InvalidSecretKey)")]
fn schnorr_broken_privkey_ffs() {
// Xpriv having secret key set to all 0xFF's
let xpriv_str = "xprv9s21ZrQH143K24Mfq5zL5MhWK9hUhhGbd45hLXo2Pq2oqzMMo63oStZzFAzHGBP2UuGCqWLTAPLcMtD9y5gkZ6Eq3Rjuahrv17fENZ3QzxW";
Xpriv::from_str(xpriv_str).unwrap();
}
}