Struct Keypair

pub struct Keypair(/* private fields */);

Opaque data structure that holds a keypair consisting of a secret and a public key.

Serde support

Implements de/serialization with the serde and_global-context features enabled. Serializes the secret bytes only. We treat the byte value as a tuple of 32 u8s for non-human-readable formats. This representation is optimal for for some formats (e.g. bincode) however other formats may be less optimal (e.g. cbor). For human-readable formats we use a hex string.

Examples

Basic usage:

use secp256k1::{rand, Keypair, Secp256k1};

let secp = Secp256k1::new();
let (secret_key, public_key) = secp.generate_keypair(&mut rand::thread_rng());
let keypair = Keypair::from_secret_key(&secp, &secret_key);

Implementations

impl Keypair

pub fn display_secret(&self) -> DisplaySecret

Formats the explicit byte value of the secret key kept inside the type as a little-endian hexadecimal string using the provided formatter.

This is the only method that outputs the actual secret key value, and, thus, should be used with extreme precaution.

Example

use secp256k1::{Keypair, Secp256k1, SecretKey};

let secp = Secp256k1::new();
let key = SecretKey::from_str("0000000000000000000000000000000000000000000000000000000000000001").unwrap();
let key = Keypair::from_secret_key(&secp, &key);
// Here we explicitly display the secret value:
assert_eq!(
    "0000000000000000000000000000000000000000000000000000000000000001",
    format!("{}", key.display_secret())
);
// Also, we can explicitly display with `Debug`:
assert_eq!(
    format!("{:?}", key.display_secret()),
    format!("DisplaySecret(\"{}\")", key.display_secret())
);

impl Keypair

pub fn cmp_fast_unstable(&self, other: &Keypair) -> Ordering

Like cmp::Cmp but faster and with no guarantees across library versions.

The Cmp implementation for FFI types is stable but slow because it first serializes self and other before comparing them. This function provides a faster comparison if you know that your types come from the same library version.

pub fn eq_fast_unstable(&self, other: &Keypair) -> bool

Like cmp::Eq but faster and with no guarantees across library versions.

The Eq implementation for FFI types is stable but slow because it first serializes self and other before comparing them. This function provides a faster equality check if you know that your types come from the same library version.

impl Keypair

pub fn as_ptr(&self) -> *const Keypair

👎Deprecated since 0.25.0: Use Self::as_c_ptr if you need to access the FFI layer

Obtains a raw const pointer suitable for use with FFI functions.

pub fn as_mut_ptr(&mut self) -> *mut Keypair

👎Deprecated since 0.25.0: Use Self::as_mut_c_ptr if you need to access the FFI layer

Obtains a raw mutable pointer suitable for use with FFI functions.

pub fn from_secret_key<C>(secp: &Secp256k1<C>, sk: &SecretKey) -> Keypair

where C: Signing,

Creates a Keypair directly from a Secp256k1 secret key.

pub fn from_seckey_slice<C>( secp: &Secp256k1<C>, data: &[u8], ) -> Result<Keypair, Error>

where C: Signing,

Creates a Keypair directly from a secret key slice.

Errors

Error::InvalidSecretKey if the provided data has an incorrect length, exceeds Secp256k1 field p value or the corresponding public key is not even.

pub fn from_seckey_str<C>( secp: &Secp256k1<C>, s: &str, ) -> Result<Keypair, Error>

where C: Signing,

Creates a Keypair directly from a secret key string.

Errors

Error::InvalidSecretKey if corresponding public key for the provided secret key is not even.

pub fn new<R, C>(secp: &Secp256k1<C>, rng: &mut R) -> Keypair

where R: Rng + ?Sized, C: Signing,

Available on crate feature rand only.

Generates a new random secret key.

Examples

use secp256k1::{rand, Secp256k1, SecretKey, Keypair};

let secp = Secp256k1::new();
let keypair = Keypair::new(&secp, &mut rand::thread_rng());

pub fn secret_bytes(&self) -> [u8; 32]

Returns the secret bytes for this key pair.

pub fn add_xonly_tweak<C>( self, secp: &Secp256k1<C>, tweak: &Scalar, ) -> Result<Keypair, Error>

where C: Verification,

Tweaks a keypair by first converting the public key to an xonly key and tweaking it.

Errors

Returns an error if the resulting key would be invalid.

NB: Will not error if the tweaked public key has an odd value and can’t be used for BIP 340-342 purposes.

Examples

use secp256k1::{Secp256k1, Keypair, Scalar};

let secp = Secp256k1::new();
let tweak = Scalar::random();

let mut keypair = Keypair::new(&secp, &mut rand::thread_rng());
let tweaked = keypair.add_xonly_tweak(&secp, &tweak).expect("Improbable to fail with a randomly generated tweak");

pub fn secret_key(&self) -> SecretKey

Returns the SecretKey for this Keypair.

This is equivalent to using SecretKey::from_keypair.

pub fn public_key(&self) -> PublicKey

Returns the PublicKey for this Keypair.

This is equivalent to using PublicKey::from_keypair.

pub fn x_only_public_key(&self) -> (XOnlyPublicKey, Parity)

Returns the XOnlyPublicKey (and it’s Parity) for this Keypair.

This is equivalent to using XOnlyPublicKey::from_keypair.

pub fn non_secure_erase(&mut self)

Attempts to erase the secret within the underlying array.

Note, however, that the compiler is allowed to freely copy or move the contents of this array to other places in memory. Preventing this behavior is very subtle. For more discussion on this, please see the documentation of the zeroize crate.

Trait Implementations

impl CPtr for Keypair

type Target = Keypair

fn as_c_ptr(&self) -> *const <Keypair as CPtr>::Target

fn as_mut_c_ptr(&mut self) -> *mut <Keypair as CPtr>::Target

impl Clone for Keypair

fn clone(&self) -> Keypair

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Keypair

Available on crate feature std only.

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Keypair

Available on crate feature serde only.

fn deserialize<D>(d: D) -> Result<Keypair, <D as Deserializer<'de>>::Error>

where D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl From<TweakedKeypair> for Keypair

fn from(pair: TweakedKeypair) -> Self

Converts to this type from the input type.

impl FromStr for Keypair

type Err = Error

The associated error which can be returned from parsing.

fn from_str(s: &str) -> Result<Keypair, <Keypair as FromStr>::Err>

Parses a string s to return a value of this type.

impl Hash for Keypair

fn hash<__H>(&self, state: &mut __H)

where __H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for Keypair

fn cmp(&self, other: &Keypair) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for Keypair

fn eq(&self, other: &Keypair) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for Keypair

fn partial_cmp(&self, other: &Keypair) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Serialize for Keypair

Available on crate feature serde only.

fn serialize<S>( &self, s: S, ) -> Result<<S as Serializer>::Ok, <S as Serializer>::Error>

where S: Serializer,

Serialize this value into the given Serde serializer.

impl Copy for Keypair

impl Eq for Keypair

impl StructuralPartialEq for Keypair