Struct Keypair

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

Expand description

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,

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.