bitcoin/
bip32.rs

1// SPDX-License-Identifier: CC0-1.0
2
3//! BIP32 implementation.
4//!
5//! Implementation of BIP32 hierarchical deterministic wallets, as defined
6//! at <https://github.com/bitcoin/bips/blob/master/bip-0032.mediawiki>.
7//!
8
9use core::ops::Index;
10use core::str::FromStr;
11use core::{fmt, slice};
12
13use hashes::{hash160, hash_newtype, sha512, Hash, HashEngine, Hmac, HmacEngine};
14use internals::{impl_array_newtype, write_err};
15use io::Write;
16use secp256k1::{Secp256k1, XOnlyPublicKey};
17
18use crate::crypto::key::{CompressedPublicKey, Keypair, PrivateKey};
19use crate::internal_macros::impl_bytes_newtype;
20use crate::network::NetworkKind;
21use crate::prelude::*;
22
23/// Version bytes for extended public keys on the Bitcoin network.
24const VERSION_BYTES_MAINNET_PUBLIC: [u8; 4] = [0x04, 0x88, 0xB2, 0x1E];
25/// Version bytes for extended private keys on the Bitcoin network.
26const VERSION_BYTES_MAINNET_PRIVATE: [u8; 4] = [0x04, 0x88, 0xAD, 0xE4];
27/// Version bytes for extended public keys on any of the testnet networks.
28const VERSION_BYTES_TESTNETS_PUBLIC: [u8; 4] = [0x04, 0x35, 0x87, 0xCF];
29/// Version bytes for extended private keys on any of the testnet networks.
30const VERSION_BYTES_TESTNETS_PRIVATE: [u8; 4] = [0x04, 0x35, 0x83, 0x94];
31
32/// The old name for xpub, extended public key.
33#[deprecated(since = "0.31.0", note = "use xpub instead")]
34pub type ExtendedPubKey = Xpub;
35
36/// The old name for xpub, extended public key (with a released typo in it).
37#[deprecated(since = "0.31.0", note = "use xpub instead")]
38pub type ExtendendPubKey = Xpub;
39
40/// The old name for xpriv, extended public key.
41#[deprecated(since = "0.31.0", note = "use xpriv instead")]
42pub type ExtendedPrivKey = Xpriv;
43
44/// The old name for xpriv, extended public key (with a released typo in it).
45#[deprecated(since = "0.31.0", note = "use xpriv instead")]
46pub type ExtendendPrivKey = Xpriv;
47
48/// A chain code
49#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
50pub struct ChainCode([u8; 32]);
51impl_array_newtype!(ChainCode, u8, 32);
52impl_bytes_newtype!(ChainCode, 32);
53
54impl ChainCode {
55    fn from_hmac(hmac: Hmac<sha512::Hash>) -> Self {
56        hmac[32..].try_into().expect("half of hmac is guaranteed to be 32 bytes")
57    }
58}
59
60/// A fingerprint
61#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Default)]
62pub struct Fingerprint([u8; 4]);
63impl_array_newtype!(Fingerprint, u8, 4);
64impl_bytes_newtype!(Fingerprint, 4);
65
66hash_newtype! {
67    /// Extended key identifier as defined in BIP-32.
68    pub struct XKeyIdentifier(hash160::Hash);
69}
70
71/// Extended private key
72#[derive(Copy, Clone, PartialEq, Eq)]
73#[cfg_attr(feature = "std", derive(Debug))]
74pub struct Xpriv {
75    /// The network this key is to be used on
76    pub network: NetworkKind,
77    /// How many derivations this key is from the master (which is 0)
78    pub depth: u8,
79    /// Fingerprint of the parent key (0 for master)
80    pub parent_fingerprint: Fingerprint,
81    /// Child number of the key used to derive from parent (0 for master)
82    pub child_number: ChildNumber,
83    /// Private key
84    pub private_key: secp256k1::SecretKey,
85    /// Chain code
86    pub chain_code: ChainCode,
87}
88#[cfg(feature = "serde")]
89crate::serde_utils::serde_string_impl!(Xpriv, "a BIP-32 extended private key");
90
91#[cfg(not(feature = "std"))]
92impl fmt::Debug for Xpriv {
93    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
94        f.debug_struct("Xpriv")
95            .field("network", &self.network)
96            .field("depth", &self.depth)
97            .field("parent_fingerprint", &self.parent_fingerprint)
98            .field("child_number", &self.child_number)
99            .field("chain_code", &self.chain_code)
100            .field("private_key", &"[SecretKey]")
101            .finish()
102    }
103}
104
105/// Extended public key
106#[derive(Copy, Clone, PartialEq, Eq, Debug, PartialOrd, Ord, Hash)]
107pub struct Xpub {
108    /// The network kind this key is to be used on
109    pub network: NetworkKind,
110    /// How many derivations this key is from the master (which is 0)
111    pub depth: u8,
112    /// Fingerprint of the parent key
113    pub parent_fingerprint: Fingerprint,
114    /// Child number of the key used to derive from parent (0 for master)
115    pub child_number: ChildNumber,
116    /// Public key
117    pub public_key: secp256k1::PublicKey,
118    /// Chain code
119    pub chain_code: ChainCode,
120}
121#[cfg(feature = "serde")]
122crate::serde_utils::serde_string_impl!(Xpub, "a BIP-32 extended public key");
123
124/// A child number for a derived key
125#[derive(Copy, Clone, PartialEq, Eq, Debug, PartialOrd, Ord, Hash)]
126pub enum ChildNumber {
127    /// Non-hardened key
128    Normal {
129        /// Key index, within [0, 2^31 - 1]
130        index: u32,
131    },
132    /// Hardened key
133    Hardened {
134        /// Key index, within [0, 2^31 - 1]
135        index: u32,
136    },
137}
138
139impl ChildNumber {
140    /// Create a [`Normal`] from an index, returns an error if the index is not within
141    /// [0, 2^31 - 1].
142    ///
143    /// [`Normal`]: #variant.Normal
144    pub fn from_normal_idx(index: u32) -> Result<Self, Error> {
145        if index & (1 << 31) == 0 {
146            Ok(ChildNumber::Normal { index })
147        } else {
148            Err(Error::InvalidChildNumber(index))
149        }
150    }
151
152    /// Create a [`Hardened`] from an index, returns an error if the index is not within
153    /// [0, 2^31 - 1].
154    ///
155    /// [`Hardened`]: #variant.Hardened
156    pub fn from_hardened_idx(index: u32) -> Result<Self, Error> {
157        if index & (1 << 31) == 0 {
158            Ok(ChildNumber::Hardened { index })
159        } else {
160            Err(Error::InvalidChildNumber(index))
161        }
162    }
163
164    /// Returns `true` if the child number is a [`Normal`] value.
165    ///
166    /// [`Normal`]: #variant.Normal
167    pub fn is_normal(&self) -> bool { !self.is_hardened() }
168
169    /// Returns `true` if the child number is a [`Hardened`] value.
170    ///
171    /// [`Hardened`]: #variant.Hardened
172    pub fn is_hardened(&self) -> bool {
173        match self {
174            ChildNumber::Hardened { .. } => true,
175            ChildNumber::Normal { .. } => false,
176        }
177    }
178
179    /// Returns the child number that is a single increment from this one.
180    pub fn increment(self) -> Result<ChildNumber, Error> {
181        match self {
182            ChildNumber::Normal { index: idx } => ChildNumber::from_normal_idx(idx + 1),
183            ChildNumber::Hardened { index: idx } => ChildNumber::from_hardened_idx(idx + 1),
184        }
185    }
186}
187
188impl From<u32> for ChildNumber {
189    fn from(number: u32) -> Self {
190        if number & (1 << 31) != 0 {
191            ChildNumber::Hardened { index: number ^ (1 << 31) }
192        } else {
193            ChildNumber::Normal { index: number }
194        }
195    }
196}
197
198impl From<ChildNumber> for u32 {
199    fn from(cnum: ChildNumber) -> Self {
200        match cnum {
201            ChildNumber::Normal { index } => index,
202            ChildNumber::Hardened { index } => index | (1 << 31),
203        }
204    }
205}
206
207impl fmt::Display for ChildNumber {
208    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
209        match *self {
210            ChildNumber::Hardened { index } => {
211                fmt::Display::fmt(&index, f)?;
212                let alt = f.alternate();
213                f.write_str(if alt { "h" } else { "'" })
214            }
215            ChildNumber::Normal { index } => fmt::Display::fmt(&index, f),
216        }
217    }
218}
219
220impl FromStr for ChildNumber {
221    type Err = Error;
222
223    fn from_str(inp: &str) -> Result<ChildNumber, Error> {
224        let is_hardened = inp.chars().last().map_or(false, |l| l == '\'' || l == 'h');
225        Ok(if is_hardened {
226            ChildNumber::from_hardened_idx(
227                inp[0..inp.len() - 1].parse().map_err(|_| Error::InvalidChildNumberFormat)?,
228            )?
229        } else {
230            ChildNumber::from_normal_idx(inp.parse().map_err(|_| Error::InvalidChildNumberFormat)?)?
231        })
232    }
233}
234
235impl AsRef<[ChildNumber]> for ChildNumber {
236    fn as_ref(&self) -> &[ChildNumber] { slice::from_ref(self) }
237}
238
239#[cfg(feature = "serde")]
240impl<'de> serde::Deserialize<'de> for ChildNumber {
241    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
242    where
243        D: serde::Deserializer<'de>,
244    {
245        u32::deserialize(deserializer).map(ChildNumber::from)
246    }
247}
248
249#[cfg(feature = "serde")]
250impl serde::Serialize for ChildNumber {
251    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
252    where
253        S: serde::Serializer,
254    {
255        u32::from(*self).serialize(serializer)
256    }
257}
258
259/// Trait that allows possibly failable conversion from a type into a
260/// derivation path
261pub trait IntoDerivationPath {
262    /// Converts a given type into a [`DerivationPath`] with possible error
263    fn into_derivation_path(self) -> Result<DerivationPath, Error>;
264}
265
266/// A BIP-32 derivation path.
267#[derive(Clone, PartialEq, Eq, Ord, PartialOrd, Hash)]
268pub struct DerivationPath(Vec<ChildNumber>);
269
270#[cfg(feature = "serde")]
271crate::serde_utils::serde_string_impl!(DerivationPath, "a BIP-32 derivation path");
272
273impl<I> Index<I> for DerivationPath
274where
275    Vec<ChildNumber>: Index<I>,
276{
277    type Output = <Vec<ChildNumber> as Index<I>>::Output;
278
279    #[inline]
280    fn index(&self, index: I) -> &Self::Output { &self.0[index] }
281}
282
283impl Default for DerivationPath {
284    fn default() -> DerivationPath { DerivationPath::master() }
285}
286
287impl<T> IntoDerivationPath for T
288where
289    T: Into<DerivationPath>,
290{
291    fn into_derivation_path(self) -> Result<DerivationPath, Error> { Ok(self.into()) }
292}
293
294impl IntoDerivationPath for String {
295    fn into_derivation_path(self) -> Result<DerivationPath, Error> { self.parse() }
296}
297
298impl<'a> IntoDerivationPath for &'a str {
299    fn into_derivation_path(self) -> Result<DerivationPath, Error> { self.parse() }
300}
301
302impl From<Vec<ChildNumber>> for DerivationPath {
303    fn from(numbers: Vec<ChildNumber>) -> Self { DerivationPath(numbers) }
304}
305
306impl From<DerivationPath> for Vec<ChildNumber> {
307    fn from(path: DerivationPath) -> Self { path.0 }
308}
309
310impl<'a> From<&'a [ChildNumber]> for DerivationPath {
311    fn from(numbers: &'a [ChildNumber]) -> Self { DerivationPath(numbers.to_vec()) }
312}
313
314impl core::iter::FromIterator<ChildNumber> for DerivationPath {
315    fn from_iter<T>(iter: T) -> Self
316    where
317        T: IntoIterator<Item = ChildNumber>,
318    {
319        DerivationPath(Vec::from_iter(iter))
320    }
321}
322
323impl<'a> core::iter::IntoIterator for &'a DerivationPath {
324    type Item = &'a ChildNumber;
325    type IntoIter = slice::Iter<'a, ChildNumber>;
326    fn into_iter(self) -> Self::IntoIter { self.0.iter() }
327}
328
329impl AsRef<[ChildNumber]> for DerivationPath {
330    fn as_ref(&self) -> &[ChildNumber] { &self.0 }
331}
332
333impl FromStr for DerivationPath {
334    type Err = Error;
335
336    fn from_str(path: &str) -> Result<DerivationPath, Error> {
337        if path.is_empty() || path == "m" || path == "m/" {
338            return Ok(vec![].into());
339        }
340
341        let path = path.strip_prefix("m/").unwrap_or(path);
342
343        let parts = path.split('/');
344        let ret: Result<Vec<ChildNumber>, Error> = parts.map(str::parse).collect();
345        Ok(DerivationPath(ret?))
346    }
347}
348
349/// An iterator over children of a [DerivationPath].
350///
351/// It is returned by the methods [DerivationPath::children_from],
352/// [DerivationPath::normal_children] and [DerivationPath::hardened_children].
353pub struct DerivationPathIterator<'a> {
354    base: &'a DerivationPath,
355    next_child: Option<ChildNumber>,
356}
357
358impl<'a> DerivationPathIterator<'a> {
359    /// Start a new [DerivationPathIterator] at the given child.
360    pub fn start_from(path: &'a DerivationPath, start: ChildNumber) -> DerivationPathIterator<'a> {
361        DerivationPathIterator { base: path, next_child: Some(start) }
362    }
363}
364
365impl<'a> Iterator for DerivationPathIterator<'a> {
366    type Item = DerivationPath;
367
368    fn next(&mut self) -> Option<Self::Item> {
369        let ret = self.next_child?;
370        self.next_child = ret.increment().ok();
371        Some(self.base.child(ret))
372    }
373}
374
375impl DerivationPath {
376    /// Returns length of the derivation path
377    pub fn len(&self) -> usize { self.0.len() }
378
379    /// Returns `true` if the derivation path is empty
380    pub fn is_empty(&self) -> bool { self.0.is_empty() }
381
382    /// Returns derivation path for a master key (i.e. empty derivation path)
383    pub fn master() -> DerivationPath { DerivationPath(vec![]) }
384
385    /// Returns whether derivation path represents master key (i.e. it's length
386    /// is empty). True for `m` path.
387    pub fn is_master(&self) -> bool { self.0.is_empty() }
388
389    /// Create a new [DerivationPath] that is a child of this one.
390    pub fn child(&self, cn: ChildNumber) -> DerivationPath {
391        let mut path = self.0.clone();
392        path.push(cn);
393        DerivationPath(path)
394    }
395
396    /// Convert into a [DerivationPath] that is a child of this one.
397    pub fn into_child(self, cn: ChildNumber) -> DerivationPath {
398        let mut path = self.0;
399        path.push(cn);
400        DerivationPath(path)
401    }
402
403    /// Get an [Iterator] over the children of this [DerivationPath]
404    /// starting with the given [ChildNumber].
405    pub fn children_from(&self, cn: ChildNumber) -> DerivationPathIterator {
406        DerivationPathIterator::start_from(self, cn)
407    }
408
409    /// Get an [Iterator] over the unhardened children of this [DerivationPath].
410    pub fn normal_children(&self) -> DerivationPathIterator {
411        DerivationPathIterator::start_from(self, ChildNumber::Normal { index: 0 })
412    }
413
414    /// Get an [Iterator] over the hardened children of this [DerivationPath].
415    pub fn hardened_children(&self) -> DerivationPathIterator {
416        DerivationPathIterator::start_from(self, ChildNumber::Hardened { index: 0 })
417    }
418
419    /// Concatenate `self` with `path` and return the resulting new path.
420    ///
421    /// ```
422    /// use bitcoin::bip32::{DerivationPath, ChildNumber};
423    /// use std::str::FromStr;
424    ///
425    /// let base = DerivationPath::from_str("m/42").unwrap();
426    ///
427    /// let deriv_1 = base.extend(DerivationPath::from_str("0/1").unwrap());
428    /// let deriv_2 = base.extend(&[
429    ///     ChildNumber::from_normal_idx(0).unwrap(),
430    ///     ChildNumber::from_normal_idx(1).unwrap()
431    /// ]);
432    ///
433    /// assert_eq!(deriv_1, deriv_2);
434    /// ```
435    pub fn extend<T: AsRef<[ChildNumber]>>(&self, path: T) -> DerivationPath {
436        let mut new_path = self.clone();
437        new_path.0.extend_from_slice(path.as_ref());
438        new_path
439    }
440
441    /// Returns the derivation path as a vector of u32 integers.
442    /// Unhardened elements are copied as is.
443    /// 0x80000000 is added to the hardened elements.
444    ///
445    /// ```
446    /// use bitcoin::bip32::DerivationPath;
447    /// use std::str::FromStr;
448    ///
449    /// let path = DerivationPath::from_str("m/84'/0'/0'/0/1").unwrap();
450    /// const HARDENED: u32 = 0x80000000;
451    /// assert_eq!(path.to_u32_vec(), vec![84 + HARDENED, HARDENED, HARDENED, 0, 1]);
452    /// ```
453    pub fn to_u32_vec(&self) -> Vec<u32> { self.into_iter().map(|&el| el.into()).collect() }
454}
455
456impl fmt::Display for DerivationPath {
457    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
458        let mut iter = self.0.iter();
459        if let Some(first_element) = iter.next() {
460            write!(f, "{}", first_element)?;
461        }
462        for cn in iter {
463            f.write_str("/")?;
464            write!(f, "{}", cn)?;
465        }
466        Ok(())
467    }
468}
469
470impl fmt::Debug for DerivationPath {
471    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { fmt::Display::fmt(&self, f) }
472}
473
474/// Full information on the used extended public key: fingerprint of the
475/// master extended public key and a derivation path from it.
476pub type KeySource = (Fingerprint, DerivationPath);
477
478/// A BIP32 error
479#[derive(Debug, Clone, PartialEq, Eq)]
480#[non_exhaustive]
481pub enum Error {
482    /// A pk->pk derivation was attempted on a hardened key
483    CannotDeriveFromHardenedKey,
484    /// A secp256k1 error occurred
485    Secp256k1(secp256k1::Error),
486    /// A child number was provided that was out of range
487    InvalidChildNumber(u32),
488    /// Invalid childnumber format.
489    InvalidChildNumberFormat,
490    /// Invalid derivation path format.
491    InvalidDerivationPathFormat,
492    /// Unknown version magic bytes
493    UnknownVersion([u8; 4]),
494    /// Encoded extended key data has wrong length
495    WrongExtendedKeyLength(usize),
496    /// Base58 encoding error
497    Base58(base58::Error),
498    /// Hexadecimal decoding error
499    Hex(hex::HexToArrayError),
500    /// `PublicKey` hex should be 66 or 130 digits long.
501    InvalidPublicKeyHexLength(usize),
502    /// Base58 decoded data was an invalid length.
503    InvalidBase58PayloadLength(InvalidBase58PayloadLengthError),
504}
505
506internals::impl_from_infallible!(Error);
507
508impl fmt::Display for Error {
509    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
510        use Error::*;
511
512        match *self {
513            CannotDeriveFromHardenedKey =>
514                f.write_str("cannot derive hardened key from public key"),
515            Secp256k1(ref e) => write_err!(f, "secp256k1 error"; e),
516            InvalidChildNumber(ref n) =>
517                write!(f, "child number {} is invalid (not within [0, 2^31 - 1])", n),
518            InvalidChildNumberFormat => f.write_str("invalid child number format"),
519            InvalidDerivationPathFormat => f.write_str("invalid derivation path format"),
520            UnknownVersion(ref bytes) => write!(f, "unknown version magic bytes: {:?}", bytes),
521            WrongExtendedKeyLength(ref len) =>
522                write!(f, "encoded extended key data has wrong length {}", len),
523            Base58(ref e) => write_err!(f, "base58 encoding error"; e),
524            Hex(ref e) => write_err!(f, "Hexadecimal decoding error"; e),
525            InvalidPublicKeyHexLength(got) =>
526                write!(f, "PublicKey hex should be 66 or 130 digits long, got: {}", got),
527            InvalidBase58PayloadLength(ref e) => write_err!(f, "base58 payload"; e),
528        }
529    }
530}
531
532#[cfg(feature = "std")]
533impl std::error::Error for Error {
534    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
535        use Error::*;
536
537        match *self {
538            Secp256k1(ref e) => Some(e),
539            Base58(ref e) => Some(e),
540            Hex(ref e) => Some(e),
541            InvalidBase58PayloadLength(ref e) => Some(e),
542            CannotDeriveFromHardenedKey
543            | InvalidChildNumber(_)
544            | InvalidChildNumberFormat
545            | InvalidDerivationPathFormat
546            | UnknownVersion(_)
547            | WrongExtendedKeyLength(_)
548            | InvalidPublicKeyHexLength(_) => None,
549        }
550    }
551}
552
553impl From<secp256k1::Error> for Error {
554    fn from(e: secp256k1::Error) -> Error { Error::Secp256k1(e) }
555}
556
557impl From<base58::Error> for Error {
558    fn from(err: base58::Error) -> Self { Error::Base58(err) }
559}
560
561impl From<InvalidBase58PayloadLengthError> for Error {
562    fn from(e: InvalidBase58PayloadLengthError) -> Error { Self::InvalidBase58PayloadLength(e) }
563}
564
565impl Xpriv {
566    /// Construct a new master key from a seed value
567    pub fn new_master(network: impl Into<NetworkKind>, seed: &[u8]) -> Result<Xpriv, Error> {
568        let mut hmac_engine: HmacEngine<sha512::Hash> = HmacEngine::new(b"Bitcoin seed");
569        hmac_engine.input(seed);
570        let hmac_result: Hmac<sha512::Hash> = Hmac::from_engine(hmac_engine);
571
572        Ok(Xpriv {
573            network: network.into(),
574            depth: 0,
575            parent_fingerprint: Default::default(),
576            child_number: ChildNumber::from_normal_idx(0)?,
577            private_key: secp256k1::SecretKey::from_slice(&hmac_result[..32])?,
578            chain_code: ChainCode::from_hmac(hmac_result),
579        })
580    }
581
582    /// Constructs ECDSA compressed private key matching internal secret key representation.
583    pub fn to_priv(self) -> PrivateKey {
584        PrivateKey { compressed: true, network: self.network, inner: self.private_key }
585    }
586
587    /// Constructs BIP340 keypair for Schnorr signatures and Taproot use matching the internal
588    /// secret key representation.
589    pub fn to_keypair<C: secp256k1::Signing>(self, secp: &Secp256k1<C>) -> Keypair {
590        Keypair::from_seckey_slice(secp, &self.private_key[..])
591            .expect("BIP32 internal private key representation is broken")
592    }
593
594    /// Attempts to derive an extended private key from a path.
595    ///
596    /// The `path` argument can be both of type `DerivationPath` or `Vec<ChildNumber>`.
597    pub fn derive_priv<C: secp256k1::Signing, P: AsRef<[ChildNumber]>>(
598        &self,
599        secp: &Secp256k1<C>,
600        path: &P,
601    ) -> Result<Xpriv, Error> {
602        let mut sk: Xpriv = *self;
603        for cnum in path.as_ref() {
604            sk = sk.ckd_priv(secp, *cnum)?;
605        }
606        Ok(sk)
607    }
608
609    /// Private->Private child key derivation
610    fn ckd_priv<C: secp256k1::Signing>(
611        &self,
612        secp: &Secp256k1<C>,
613        i: ChildNumber,
614    ) -> Result<Xpriv, Error> {
615        let mut hmac_engine: HmacEngine<sha512::Hash> = HmacEngine::new(&self.chain_code[..]);
616        match i {
617            ChildNumber::Normal { .. } => {
618                // Non-hardened key: compute public data and use that
619                hmac_engine.input(
620                    &secp256k1::PublicKey::from_secret_key(secp, &self.private_key).serialize()[..],
621                );
622            }
623            ChildNumber::Hardened { .. } => {
624                // Hardened key: use only secret data to prevent public derivation
625                hmac_engine.input(&[0u8]);
626                hmac_engine.input(&self.private_key[..]);
627            }
628        }
629
630        hmac_engine.input(&u32::from(i).to_be_bytes());
631        let hmac_result: Hmac<sha512::Hash> = Hmac::from_engine(hmac_engine);
632        let sk = secp256k1::SecretKey::from_slice(&hmac_result[..32])
633            .expect("statistically impossible to hit");
634        let tweaked =
635            sk.add_tweak(&self.private_key.into()).expect("statistically impossible to hit");
636
637        Ok(Xpriv {
638            network: self.network,
639            depth: self.depth + 1,
640            parent_fingerprint: self.fingerprint(secp),
641            child_number: i,
642            private_key: tweaked,
643            chain_code: ChainCode::from_hmac(hmac_result),
644        })
645    }
646
647    /// Decoding extended private key from binary data according to BIP 32
648    pub fn decode(data: &[u8]) -> Result<Xpriv, Error> {
649        if data.len() != 78 {
650            return Err(Error::WrongExtendedKeyLength(data.len()));
651        }
652
653        let network = if data.starts_with(&VERSION_BYTES_MAINNET_PRIVATE) {
654            NetworkKind::Main
655        } else if data.starts_with(&VERSION_BYTES_TESTNETS_PRIVATE) {
656            NetworkKind::Test
657        } else {
658            let (b0, b1, b2, b3) = (data[0], data[1], data[2], data[3]);
659            return Err(Error::UnknownVersion([b0, b1, b2, b3]));
660        };
661
662        Ok(Xpriv {
663            network,
664            depth: data[4],
665            parent_fingerprint: data[5..9]
666                .try_into()
667                .expect("9 - 5 == 4, which is the Fingerprint length"),
668            child_number: u32::from_be_bytes(data[9..13].try_into().expect("4 byte slice")).into(),
669            chain_code: data[13..45]
670                .try_into()
671                .expect("45 - 13 == 32, which is the ChainCode length"),
672            private_key: secp256k1::SecretKey::from_slice(&data[46..78])?,
673        })
674    }
675
676    /// Extended private key binary encoding according to BIP 32
677    pub fn encode(&self) -> [u8; 78] {
678        let mut ret = [0; 78];
679        ret[0..4].copy_from_slice(&match self.network {
680            NetworkKind::Main => VERSION_BYTES_MAINNET_PRIVATE,
681            NetworkKind::Test => VERSION_BYTES_TESTNETS_PRIVATE,
682        });
683        ret[4] = self.depth;
684        ret[5..9].copy_from_slice(&self.parent_fingerprint[..]);
685        ret[9..13].copy_from_slice(&u32::from(self.child_number).to_be_bytes());
686        ret[13..45].copy_from_slice(&self.chain_code[..]);
687        ret[45] = 0;
688        ret[46..78].copy_from_slice(&self.private_key[..]);
689        ret
690    }
691
692    /// Returns the HASH160 of the public key belonging to the xpriv
693    pub fn identifier<C: secp256k1::Signing>(&self, secp: &Secp256k1<C>) -> XKeyIdentifier {
694        Xpub::from_priv(secp, self).identifier()
695    }
696
697    /// Returns the first four bytes of the identifier
698    pub fn fingerprint<C: secp256k1::Signing>(&self, secp: &Secp256k1<C>) -> Fingerprint {
699        self.identifier(secp)[0..4].try_into().expect("4 is the fingerprint length")
700    }
701}
702
703impl Xpub {
704    /// Derives a public key from a private key
705    pub fn from_priv<C: secp256k1::Signing>(secp: &Secp256k1<C>, sk: &Xpriv) -> Xpub {
706        Xpub {
707            network: sk.network,
708            depth: sk.depth,
709            parent_fingerprint: sk.parent_fingerprint,
710            child_number: sk.child_number,
711            public_key: secp256k1::PublicKey::from_secret_key(secp, &sk.private_key),
712            chain_code: sk.chain_code,
713        }
714    }
715
716    /// Constructs ECDSA compressed public key matching internal public key representation.
717    pub fn to_pub(self) -> CompressedPublicKey { CompressedPublicKey(self.public_key) }
718
719    /// Constructs BIP340 x-only public key for BIP-340 signatures and Taproot use matching
720    /// the internal public key representation.
721    pub fn to_x_only_pub(self) -> XOnlyPublicKey { XOnlyPublicKey::from(self.public_key) }
722
723    /// Attempts to derive an extended public key from a path.
724    ///
725    /// The `path` argument can be any type implementing `AsRef<ChildNumber>`, such as `DerivationPath`, for instance.
726    pub fn derive_pub<C: secp256k1::Verification, P: AsRef<[ChildNumber]>>(
727        &self,
728        secp: &Secp256k1<C>,
729        path: &P,
730    ) -> Result<Xpub, Error> {
731        let mut pk: Xpub = *self;
732        for cnum in path.as_ref() {
733            pk = pk.ckd_pub(secp, *cnum)?
734        }
735        Ok(pk)
736    }
737
738    /// Compute the scalar tweak added to this key to get a child key
739    pub fn ckd_pub_tweak(
740        &self,
741        i: ChildNumber,
742    ) -> Result<(secp256k1::SecretKey, ChainCode), Error> {
743        match i {
744            ChildNumber::Hardened { .. } => Err(Error::CannotDeriveFromHardenedKey),
745            ChildNumber::Normal { index: n } => {
746                let mut hmac_engine: HmacEngine<sha512::Hash> =
747                    HmacEngine::new(&self.chain_code[..]);
748                hmac_engine.input(&self.public_key.serialize()[..]);
749                hmac_engine.input(&n.to_be_bytes());
750
751                let hmac_result: Hmac<sha512::Hash> = Hmac::from_engine(hmac_engine);
752
753                let private_key = secp256k1::SecretKey::from_slice(&hmac_result[..32])?;
754                let chain_code = ChainCode::from_hmac(hmac_result);
755                Ok((private_key, chain_code))
756            }
757        }
758    }
759
760    /// Public->Public child key derivation
761    pub fn ckd_pub<C: secp256k1::Verification>(
762        &self,
763        secp: &Secp256k1<C>,
764        i: ChildNumber,
765    ) -> Result<Xpub, Error> {
766        let (sk, chain_code) = self.ckd_pub_tweak(i)?;
767        let tweaked = self.public_key.add_exp_tweak(secp, &sk.into())?;
768
769        Ok(Xpub {
770            network: self.network,
771            depth: self.depth + 1,
772            parent_fingerprint: self.fingerprint(),
773            child_number: i,
774            public_key: tweaked,
775            chain_code,
776        })
777    }
778
779    /// Decoding extended public key from binary data according to BIP 32
780    pub fn decode(data: &[u8]) -> Result<Xpub, Error> {
781        if data.len() != 78 {
782            return Err(Error::WrongExtendedKeyLength(data.len()));
783        }
784
785        let network = if data.starts_with(&VERSION_BYTES_MAINNET_PUBLIC) {
786            NetworkKind::Main
787        } else if data.starts_with(&VERSION_BYTES_TESTNETS_PUBLIC) {
788            NetworkKind::Test
789        } else {
790            let (b0, b1, b2, b3) = (data[0], data[1], data[2], data[3]);
791            return Err(Error::UnknownVersion([b0, b1, b2, b3]));
792        };
793
794        Ok(Xpub {
795            network,
796            depth: data[4],
797            parent_fingerprint: data[5..9]
798                .try_into()
799                .expect("9 - 5 == 4, which is the Fingerprint length"),
800            child_number: u32::from_be_bytes(data[9..13].try_into().expect("4 byte slice")).into(),
801            chain_code: data[13..45]
802                .try_into()
803                .expect("45 - 13 == 32, which is the ChainCode length"),
804            public_key: secp256k1::PublicKey::from_slice(&data[45..78])?,
805        })
806    }
807
808    /// Extended public key binary encoding according to BIP 32
809    pub fn encode(&self) -> [u8; 78] {
810        let mut ret = [0; 78];
811        ret[0..4].copy_from_slice(&match self.network {
812            NetworkKind::Main => VERSION_BYTES_MAINNET_PUBLIC,
813            NetworkKind::Test => VERSION_BYTES_TESTNETS_PUBLIC,
814        });
815        ret[4] = self.depth;
816        ret[5..9].copy_from_slice(&self.parent_fingerprint[..]);
817        ret[9..13].copy_from_slice(&u32::from(self.child_number).to_be_bytes());
818        ret[13..45].copy_from_slice(&self.chain_code[..]);
819        ret[45..78].copy_from_slice(&self.public_key.serialize()[..]);
820        ret
821    }
822
823    /// Returns the HASH160 of the chaincode
824    pub fn identifier(&self) -> XKeyIdentifier {
825        let mut engine = XKeyIdentifier::engine();
826        engine.write_all(&self.public_key.serialize()).expect("engines don't error");
827        XKeyIdentifier::from_engine(engine)
828    }
829
830    /// Returns the first four bytes of the identifier
831    pub fn fingerprint(&self) -> Fingerprint {
832        self.identifier()[0..4].try_into().expect("4 is the fingerprint length")
833    }
834}
835
836impl fmt::Display for Xpriv {
837    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
838        base58::encode_check_to_fmt(fmt, &self.encode()[..])
839    }
840}
841
842impl FromStr for Xpriv {
843    type Err = Error;
844
845    fn from_str(inp: &str) -> Result<Xpriv, Error> {
846        let data = base58::decode_check(inp)?;
847
848        if data.len() != 78 {
849            return Err(InvalidBase58PayloadLengthError { length: data.len() }.into());
850        }
851
852        Xpriv::decode(&data)
853    }
854}
855
856impl fmt::Display for Xpub {
857    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
858        base58::encode_check_to_fmt(fmt, &self.encode()[..])
859    }
860}
861
862impl FromStr for Xpub {
863    type Err = Error;
864
865    fn from_str(inp: &str) -> Result<Xpub, Error> {
866        let data = base58::decode_check(inp)?;
867
868        if data.len() != 78 {
869            return Err(InvalidBase58PayloadLengthError { length: data.len() }.into());
870        }
871
872        Xpub::decode(&data)
873    }
874}
875
876impl From<Xpub> for XKeyIdentifier {
877    fn from(key: Xpub) -> XKeyIdentifier { key.identifier() }
878}
879
880impl From<&Xpub> for XKeyIdentifier {
881    fn from(key: &Xpub) -> XKeyIdentifier { key.identifier() }
882}
883
884/// Decoded base58 data was an invalid length.
885#[derive(Debug, Clone, PartialEq, Eq)]
886pub struct InvalidBase58PayloadLengthError {
887    /// The base58 payload length we got after decoding xpriv/xpub string.
888    pub(crate) length: usize,
889}
890
891impl InvalidBase58PayloadLengthError {
892    /// Returns the invalid payload length.
893    pub fn invalid_base58_payload_length(&self) -> usize { self.length }
894}
895
896impl fmt::Display for InvalidBase58PayloadLengthError {
897    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
898        write!(
899            f,
900            "decoded base58 xpriv/xpub data was an invalid length: {} (expected 78)",
901            self.length
902        )
903    }
904}
905
906#[cfg(feature = "std")]
907impl std::error::Error for InvalidBase58PayloadLengthError {}
908
909#[cfg(test)]
910mod tests {
911    use hex::test_hex_unwrap as hex;
912
913    use super::ChildNumber::{Hardened, Normal};
914    use super::*;
915
916    #[test]
917    fn test_parse_derivation_path() {
918        assert_eq!(DerivationPath::from_str("n/0'/0"), Err(Error::InvalidChildNumberFormat));
919        assert_eq!(DerivationPath::from_str("4/m/5"), Err(Error::InvalidChildNumberFormat));
920        assert_eq!(DerivationPath::from_str("//3/0'"), Err(Error::InvalidChildNumberFormat));
921        assert_eq!(DerivationPath::from_str("0h/0x"), Err(Error::InvalidChildNumberFormat));
922        assert_eq!(
923            DerivationPath::from_str("2147483648"),
924            Err(Error::InvalidChildNumber(2147483648))
925        );
926
927        assert_eq!(DerivationPath::master(), DerivationPath::from_str("").unwrap());
928        assert_eq!(DerivationPath::master(), DerivationPath::default());
929
930        // Acceptable forms for a master path.
931        assert_eq!(DerivationPath::from_str("m").unwrap(), DerivationPath(vec![]));
932        assert_eq!(DerivationPath::from_str("m/").unwrap(), DerivationPath(vec![]));
933        assert_eq!(DerivationPath::from_str("").unwrap(), DerivationPath(vec![]));
934
935        assert_eq!(
936            DerivationPath::from_str("0'"),
937            Ok(vec![ChildNumber::from_hardened_idx(0).unwrap()].into())
938        );
939        assert_eq!(
940            DerivationPath::from_str("0'/1"),
941            Ok(vec![
942                ChildNumber::from_hardened_idx(0).unwrap(),
943                ChildNumber::from_normal_idx(1).unwrap()
944            ]
945            .into())
946        );
947        assert_eq!(
948            DerivationPath::from_str("0h/1/2'"),
949            Ok(vec![
950                ChildNumber::from_hardened_idx(0).unwrap(),
951                ChildNumber::from_normal_idx(1).unwrap(),
952                ChildNumber::from_hardened_idx(2).unwrap(),
953            ]
954            .into())
955        );
956        assert_eq!(
957            DerivationPath::from_str("0'/1/2h/2"),
958            Ok(vec![
959                ChildNumber::from_hardened_idx(0).unwrap(),
960                ChildNumber::from_normal_idx(1).unwrap(),
961                ChildNumber::from_hardened_idx(2).unwrap(),
962                ChildNumber::from_normal_idx(2).unwrap(),
963            ]
964            .into())
965        );
966        let want = DerivationPath::from(vec![
967            ChildNumber::from_hardened_idx(0).unwrap(),
968            ChildNumber::from_normal_idx(1).unwrap(),
969            ChildNumber::from_hardened_idx(2).unwrap(),
970            ChildNumber::from_normal_idx(2).unwrap(),
971            ChildNumber::from_normal_idx(1000000000).unwrap(),
972        ]);
973        assert_eq!(DerivationPath::from_str("0'/1/2'/2/1000000000").unwrap(), want);
974        assert_eq!(DerivationPath::from_str("m/0'/1/2'/2/1000000000").unwrap(), want);
975
976        let s = "0'/50/3'/5/545456";
977        assert_eq!(DerivationPath::from_str(s), s.into_derivation_path());
978        assert_eq!(DerivationPath::from_str(s), s.to_string().into_derivation_path());
979
980        let s = "m/0'/50/3'/5/545456";
981        assert_eq!(DerivationPath::from_str(s), s.into_derivation_path());
982        assert_eq!(DerivationPath::from_str(s), s.to_string().into_derivation_path());
983    }
984
985    #[test]
986    fn test_derivation_path_conversion_index() {
987        let path = DerivationPath::from_str("0h/1/2'").unwrap();
988        let numbers: Vec<ChildNumber> = path.clone().into();
989        let path2: DerivationPath = numbers.into();
990        assert_eq!(path, path2);
991        assert_eq!(
992            &path[..2],
993            &[ChildNumber::from_hardened_idx(0).unwrap(), ChildNumber::from_normal_idx(1).unwrap()]
994        );
995        let indexed: DerivationPath = path[..2].into();
996        assert_eq!(indexed, DerivationPath::from_str("0h/1").unwrap());
997        assert_eq!(indexed.child(ChildNumber::from_hardened_idx(2).unwrap()), path);
998    }
999
1000    fn test_path<C: secp256k1::Signing + secp256k1::Verification>(
1001        secp: &Secp256k1<C>,
1002        network: NetworkKind,
1003        seed: &[u8],
1004        path: DerivationPath,
1005        expected_sk: &str,
1006        expected_pk: &str,
1007    ) {
1008        let mut sk = Xpriv::new_master(network, seed).unwrap();
1009        let mut pk = Xpub::from_priv(secp, &sk);
1010
1011        // Check derivation convenience method for Xpriv
1012        assert_eq!(&sk.derive_priv(secp, &path).unwrap().to_string()[..], expected_sk);
1013
1014        // Check derivation convenience method for Xpub, should error
1015        // appropriately if any ChildNumber is hardened
1016        if path.0.iter().any(|cnum| cnum.is_hardened()) {
1017            assert_eq!(pk.derive_pub(secp, &path), Err(Error::CannotDeriveFromHardenedKey));
1018        } else {
1019            assert_eq!(&pk.derive_pub(secp, &path).unwrap().to_string()[..], expected_pk);
1020        }
1021
1022        // Derive keys, checking hardened and non-hardened derivation one-by-one
1023        for &num in path.0.iter() {
1024            sk = sk.ckd_priv(secp, num).unwrap();
1025            match num {
1026                Normal { .. } => {
1027                    let pk2 = pk.ckd_pub(secp, num).unwrap();
1028                    pk = Xpub::from_priv(secp, &sk);
1029                    assert_eq!(pk, pk2);
1030                }
1031                Hardened { .. } => {
1032                    assert_eq!(pk.ckd_pub(secp, num), Err(Error::CannotDeriveFromHardenedKey));
1033                    pk = Xpub::from_priv(secp, &sk);
1034                }
1035            }
1036        }
1037
1038        // Check result against expected base58
1039        assert_eq!(&sk.to_string()[..], expected_sk);
1040        assert_eq!(&pk.to_string()[..], expected_pk);
1041        // Check decoded base58 against result
1042        let decoded_sk = Xpriv::from_str(expected_sk);
1043        let decoded_pk = Xpub::from_str(expected_pk);
1044        assert_eq!(Ok(sk), decoded_sk);
1045        assert_eq!(Ok(pk), decoded_pk);
1046    }
1047
1048    #[test]
1049    fn test_increment() {
1050        let idx = 9345497; // randomly generated, I promise
1051        let cn = ChildNumber::from_normal_idx(idx).unwrap();
1052        assert_eq!(cn.increment().ok(), Some(ChildNumber::from_normal_idx(idx + 1).unwrap()));
1053        let cn = ChildNumber::from_hardened_idx(idx).unwrap();
1054        assert_eq!(cn.increment().ok(), Some(ChildNumber::from_hardened_idx(idx + 1).unwrap()));
1055
1056        let max = (1 << 31) - 1;
1057        let cn = ChildNumber::from_normal_idx(max).unwrap();
1058        assert_eq!(cn.increment().err(), Some(Error::InvalidChildNumber(1 << 31)));
1059        let cn = ChildNumber::from_hardened_idx(max).unwrap();
1060        assert_eq!(cn.increment().err(), Some(Error::InvalidChildNumber(1 << 31)));
1061
1062        let cn = ChildNumber::from_normal_idx(350).unwrap();
1063        let path = DerivationPath::from_str("42'").unwrap();
1064        let mut iter = path.children_from(cn);
1065        assert_eq!(iter.next(), Some("42'/350".parse().unwrap()));
1066        assert_eq!(iter.next(), Some("42'/351".parse().unwrap()));
1067
1068        let path = DerivationPath::from_str("42'/350'").unwrap();
1069        let mut iter = path.normal_children();
1070        assert_eq!(iter.next(), Some("42'/350'/0".parse().unwrap()));
1071        assert_eq!(iter.next(), Some("42'/350'/1".parse().unwrap()));
1072
1073        let path = DerivationPath::from_str("42'/350'").unwrap();
1074        let mut iter = path.hardened_children();
1075        assert_eq!(iter.next(), Some("42'/350'/0'".parse().unwrap()));
1076        assert_eq!(iter.next(), Some("42'/350'/1'".parse().unwrap()));
1077
1078        let cn = ChildNumber::from_hardened_idx(42350).unwrap();
1079        let path = DerivationPath::from_str("42'").unwrap();
1080        let mut iter = path.children_from(cn);
1081        assert_eq!(iter.next(), Some("42'/42350'".parse().unwrap()));
1082        assert_eq!(iter.next(), Some("42'/42351'".parse().unwrap()));
1083
1084        let cn = ChildNumber::from_hardened_idx(max).unwrap();
1085        let path = DerivationPath::from_str("42'").unwrap();
1086        let mut iter = path.children_from(cn);
1087        assert!(iter.next().is_some());
1088        assert!(iter.next().is_none());
1089    }
1090
1091    #[test]
1092    fn test_vector_1() {
1093        let secp = Secp256k1::new();
1094        let seed = hex!("000102030405060708090a0b0c0d0e0f");
1095
1096        // m
1097        test_path(&secp, NetworkKind::Main, &seed, "m".parse().unwrap(),
1098                  "xprv9s21ZrQH143K3QTDL4LXw2F7HEK3wJUD2nW2nRk4stbPy6cq3jPPqjiChkVvvNKmPGJxWUtg6LnF5kejMRNNU3TGtRBeJgk33yuGBxrMPHi",
1099                  "xpub661MyMwAqRbcFtXgS5sYJABqqG9YLmC4Q1Rdap9gSE8NqtwybGhePY2gZ29ESFjqJoCu1Rupje8YtGqsefD265TMg7usUDFdp6W1EGMcet8");
1100
1101        // m/0h
1102        test_path(&secp, NetworkKind::Main, &seed, "m/0h".parse().unwrap(),
1103                  "xprv9uHRZZhk6KAJC1avXpDAp4MDc3sQKNxDiPvvkX8Br5ngLNv1TxvUxt4cV1rGL5hj6KCesnDYUhd7oWgT11eZG7XnxHrnYeSvkzY7d2bhkJ7",
1104                  "xpub68Gmy5EdvgibQVfPdqkBBCHxA5htiqg55crXYuXoQRKfDBFA1WEjWgP6LHhwBZeNK1VTsfTFUHCdrfp1bgwQ9xv5ski8PX9rL2dZXvgGDnw");
1105
1106        // m/0h/1
1107        test_path(&secp, NetworkKind::Main, &seed, "m/0h/1".parse().unwrap(),
1108                   "xprv9wTYmMFdV23N2TdNG573QoEsfRrWKQgWeibmLntzniatZvR9BmLnvSxqu53Kw1UmYPxLgboyZQaXwTCg8MSY3H2EU4pWcQDnRnrVA1xe8fs",
1109                   "xpub6ASuArnXKPbfEwhqN6e3mwBcDTgzisQN1wXN9BJcM47sSikHjJf3UFHKkNAWbWMiGj7Wf5uMash7SyYq527Hqck2AxYysAA7xmALppuCkwQ");
1110
1111        // m/0h/1/2h
1112        test_path(&secp, NetworkKind::Main, &seed, "m/0h/1/2h".parse().unwrap(),
1113                  "xprv9z4pot5VBttmtdRTWfWQmoH1taj2axGVzFqSb8C9xaxKymcFzXBDptWmT7FwuEzG3ryjH4ktypQSAewRiNMjANTtpgP4mLTj34bhnZX7UiM",
1114                  "xpub6D4BDPcP2GT577Vvch3R8wDkScZWzQzMMUm3PWbmWvVJrZwQY4VUNgqFJPMM3No2dFDFGTsxxpG5uJh7n7epu4trkrX7x7DogT5Uv6fcLW5");
1115
1116        // m/0h/1/2h/2
1117        test_path(&secp, NetworkKind::Main, &seed, "m/0h/1/2h/2".parse().unwrap(),
1118                  "xprvA2JDeKCSNNZky6uBCviVfJSKyQ1mDYahRjijr5idH2WwLsEd4Hsb2Tyh8RfQMuPh7f7RtyzTtdrbdqqsunu5Mm3wDvUAKRHSC34sJ7in334",
1119                  "xpub6FHa3pjLCk84BayeJxFW2SP4XRrFd1JYnxeLeU8EqN3vDfZmbqBqaGJAyiLjTAwm6ZLRQUMv1ZACTj37sR62cfN7fe5JnJ7dh8zL4fiyLHV");
1120
1121        // m/0h/1/2h/2/1000000000
1122        test_path(&secp, NetworkKind::Main, &seed, "m/0h/1/2h/2/1000000000".parse().unwrap(),
1123                  "xprvA41z7zogVVwxVSgdKUHDy1SKmdb533PjDz7J6N6mV6uS3ze1ai8FHa8kmHScGpWmj4WggLyQjgPie1rFSruoUihUZREPSL39UNdE3BBDu76",
1124                  "xpub6H1LXWLaKsWFhvm6RVpEL9P4KfRZSW7abD2ttkWP3SSQvnyA8FSVqNTEcYFgJS2UaFcxupHiYkro49S8yGasTvXEYBVPamhGW6cFJodrTHy");
1125    }
1126
1127    #[test]
1128    fn test_vector_2() {
1129        let secp = Secp256k1::new();
1130        let seed = hex!("fffcf9f6f3f0edeae7e4e1dedbd8d5d2cfccc9c6c3c0bdbab7b4b1aeaba8a5a29f9c999693908d8a8784817e7b7875726f6c696663605d5a5754514e4b484542");
1131
1132        // m
1133        test_path(&secp, NetworkKind::Main, &seed, "m".parse().unwrap(),
1134                  "xprv9s21ZrQH143K31xYSDQpPDxsXRTUcvj2iNHm5NUtrGiGG5e2DtALGdso3pGz6ssrdK4PFmM8NSpSBHNqPqm55Qn3LqFtT2emdEXVYsCzC2U",
1135                  "xpub661MyMwAqRbcFW31YEwpkMuc5THy2PSt5bDMsktWQcFF8syAmRUapSCGu8ED9W6oDMSgv6Zz8idoc4a6mr8BDzTJY47LJhkJ8UB7WEGuduB");
1136
1137        // m/0
1138        test_path(&secp, NetworkKind::Main, &seed, "m/0".parse().unwrap(),
1139                  "xprv9vHkqa6EV4sPZHYqZznhT2NPtPCjKuDKGY38FBWLvgaDx45zo9WQRUT3dKYnjwih2yJD9mkrocEZXo1ex8G81dwSM1fwqWpWkeS3v86pgKt",
1140                  "xpub69H7F5d8KSRgmmdJg2KhpAK8SR3DjMwAdkxj3ZuxV27CprR9LgpeyGmXUbC6wb7ERfvrnKZjXoUmmDznezpbZb7ap6r1D3tgFxHmwMkQTPH");
1141
1142        // m/0/2147483647h
1143        test_path(&secp, NetworkKind::Main, &seed, "m/0/2147483647h".parse().unwrap(),
1144                  "xprv9wSp6B7kry3Vj9m1zSnLvN3xH8RdsPP1Mh7fAaR7aRLcQMKTR2vidYEeEg2mUCTAwCd6vnxVrcjfy2kRgVsFawNzmjuHc2YmYRmagcEPdU9",
1145                  "xpub6ASAVgeehLbnwdqV6UKMHVzgqAG8Gr6riv3Fxxpj8ksbH9ebxaEyBLZ85ySDhKiLDBrQSARLq1uNRts8RuJiHjaDMBU4Zn9h8LZNnBC5y4a");
1146
1147        // m/0/2147483647h/1
1148        test_path(&secp, NetworkKind::Main, &seed, "m/0/2147483647h/1".parse().unwrap(),
1149                  "xprv9zFnWC6h2cLgpmSA46vutJzBcfJ8yaJGg8cX1e5StJh45BBciYTRXSd25UEPVuesF9yog62tGAQtHjXajPPdbRCHuWS6T8XA2ECKADdw4Ef",
1150                  "xpub6DF8uhdarytz3FWdA8TvFSvvAh8dP3283MY7p2V4SeE2wyWmG5mg5EwVvmdMVCQcoNJxGoWaU9DCWh89LojfZ537wTfunKau47EL2dhHKon");
1151
1152        // m/0/2147483647h/1/2147483646h
1153        test_path(&secp, NetworkKind::Main, &seed, "m/0/2147483647h/1/2147483646h".parse().unwrap(),
1154                  "xprvA1RpRA33e1JQ7ifknakTFpgNXPmW2YvmhqLQYMmrj4xJXXWYpDPS3xz7iAxn8L39njGVyuoseXzU6rcxFLJ8HFsTjSyQbLYnMpCqE2VbFWc",
1155                  "xpub6ERApfZwUNrhLCkDtcHTcxd75RbzS1ed54G1LkBUHQVHQKqhMkhgbmJbZRkrgZw4koxb5JaHWkY4ALHY2grBGRjaDMzQLcgJvLJuZZvRcEL");
1156
1157        // m/0/2147483647h/1/2147483646h/2
1158        test_path(&secp, NetworkKind::Main, &seed, "m/0/2147483647h/1/2147483646h/2".parse().unwrap(),
1159                  "xprvA2nrNbFZABcdryreWet9Ea4LvTJcGsqrMzxHx98MMrotbir7yrKCEXw7nadnHM8Dq38EGfSh6dqA9QWTyefMLEcBYJUuekgW4BYPJcr9E7j",
1160                  "xpub6FnCn6nSzZAw5Tw7cgR9bi15UV96gLZhjDstkXXxvCLsUXBGXPdSnLFbdpq8p9HmGsApME5hQTZ3emM2rnY5agb9rXpVGyy3bdW6EEgAtqt");
1161    }
1162
1163    #[test]
1164    fn test_vector_3() {
1165        let secp = Secp256k1::new();
1166        let seed = hex!("4b381541583be4423346c643850da4b320e46a87ae3d2a4e6da11eba819cd4acba45d239319ac14f863b8d5ab5a0d0c64d2e8a1e7d1457df2e5a3c51c73235be");
1167
1168        // m
1169        test_path(&secp, NetworkKind::Main, &seed, "m".parse().unwrap(),
1170                  "xprv9s21ZrQH143K25QhxbucbDDuQ4naNntJRi4KUfWT7xo4EKsHt2QJDu7KXp1A3u7Bi1j8ph3EGsZ9Xvz9dGuVrtHHs7pXeTzjuxBrCmmhgC6",
1171                  "xpub661MyMwAqRbcEZVB4dScxMAdx6d4nFc9nvyvH3v4gJL378CSRZiYmhRoP7mBy6gSPSCYk6SzXPTf3ND1cZAceL7SfJ1Z3GC8vBgp2epUt13");
1172
1173        // m/0h
1174        test_path(&secp, NetworkKind::Main, &seed, "m/0h".parse().unwrap(),
1175                  "xprv9uPDJpEQgRQfDcW7BkF7eTya6RPxXeJCqCJGHuCJ4GiRVLzkTXBAJMu2qaMWPrS7AANYqdq6vcBcBUdJCVVFceUvJFjaPdGZ2y9WACViL4L",
1176                  "xpub68NZiKmJWnxxS6aaHmn81bvJeTESw724CRDs6HbuccFQN9Ku14VQrADWgqbhhTHBaohPX4CjNLf9fq9MYo6oDaPPLPxSb7gwQN3ih19Zm4Y");
1177    }
1178
1179    #[test]
1180    #[cfg(feature = "serde")]
1181    pub fn encode_decode_childnumber() {
1182        serde_round_trip!(ChildNumber::from_normal_idx(0).unwrap());
1183        serde_round_trip!(ChildNumber::from_normal_idx(1).unwrap());
1184        serde_round_trip!(ChildNumber::from_normal_idx((1 << 31) - 1).unwrap());
1185        serde_round_trip!(ChildNumber::from_hardened_idx(0).unwrap());
1186        serde_round_trip!(ChildNumber::from_hardened_idx(1).unwrap());
1187        serde_round_trip!(ChildNumber::from_hardened_idx((1 << 31) - 1).unwrap());
1188    }
1189
1190    #[test]
1191    #[cfg(feature = "serde")]
1192    pub fn encode_fingerprint_chaincode() {
1193        use serde_json;
1194        let fp = Fingerprint::from([1u8, 2, 3, 42]);
1195        #[rustfmt::skip]
1196        let cc = ChainCode::from(
1197            [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]
1198        );
1199
1200        serde_round_trip!(fp);
1201        serde_round_trip!(cc);
1202
1203        assert_eq!("\"0102032a\"", serde_json::to_string(&fp).unwrap());
1204        assert_eq!(
1205            "\"0102030405060708090001020304050607080900010203040506070809000102\"",
1206            serde_json::to_string(&cc).unwrap()
1207        );
1208        assert_eq!("0102032a", fp.to_string());
1209        assert_eq!(
1210            "0102030405060708090001020304050607080900010203040506070809000102",
1211            cc.to_string()
1212        );
1213    }
1214
1215    #[test]
1216    fn fmt_child_number() {
1217        assert_eq!("000005h", &format!("{:#06}", ChildNumber::from_hardened_idx(5).unwrap()));
1218        assert_eq!("5h", &format!("{:#}", ChildNumber::from_hardened_idx(5).unwrap()));
1219        assert_eq!("000005'", &format!("{:06}", ChildNumber::from_hardened_idx(5).unwrap()));
1220        assert_eq!("5'", &format!("{}", ChildNumber::from_hardened_idx(5).unwrap()));
1221        assert_eq!("42", &format!("{}", ChildNumber::from_normal_idx(42).unwrap()));
1222        assert_eq!("000042", &format!("{:06}", ChildNumber::from_normal_idx(42).unwrap()));
1223    }
1224
1225    #[test]
1226    #[should_panic(expected = "Secp256k1(InvalidSecretKey)")]
1227    fn schnorr_broken_privkey_zeros() {
1228        /* this is how we generate key:
1229        let mut sk = secp256k1::key::ONE_KEY;
1230
1231        let zeros = [0u8; 32];
1232        unsafe {
1233            sk.as_mut_ptr().copy_from(zeros.as_ptr(), 32);
1234        }
1235
1236        let xpriv = Xpriv {
1237            network: NetworkKind::Main,
1238            depth: 0,
1239            parent_fingerprint: Default::default(),
1240            child_number: ChildNumber::Normal { index: 0 },
1241            private_key: sk,
1242            chain_code: ChainCode::from([0u8; 32])
1243        };
1244
1245        println!("{}", xpriv);
1246         */
1247
1248        // Xpriv having secret key set to all zeros
1249        let xpriv_str = "xprv9s21ZrQH143K24Mfq5zL5MhWK9hUhhGbd45hLXo2Pq2oqzMMo63oStZzF93Y5wvzdUayhgkkFoicQZcP3y52uPPxFnfoLZB21Teqt1VvEHx";
1250        Xpriv::from_str(xpriv_str).unwrap();
1251    }
1252
1253    #[test]
1254    #[should_panic(expected = "Secp256k1(InvalidSecretKey)")]
1255    fn schnorr_broken_privkey_ffs() {
1256        // Xpriv having secret key set to all 0xFF's
1257        let xpriv_str = "xprv9s21ZrQH143K24Mfq5zL5MhWK9hUhhGbd45hLXo2Pq2oqzMMo63oStZzFAzHGBP2UuGCqWLTAPLcMtD9y5gkZ6Eq3Rjuahrv17fENZ3QzxW";
1258        Xpriv::from_str(xpriv_str).unwrap();
1259    }
1260}
bitcoin/bip32.rs

bitcoin/
bip32.rs
