Struct k256::Secp256k1

pub struct Secp256k1;

secp256k1 (K-256) elliptic curve.

Specified in Certicom’s SECG in “SEC 2: Recommended Elliptic Curve Domain Parameters”:

https://www.secg.org/sec2-v2.pdf

The curve’s equation is y² = x³ + 7 over a ~256-bit prime field.

It’s primarily notable for usage in Bitcoin and other cryptocurrencies, particularly in conjunction with the Elliptic Curve Digital Signature Algorithm (ECDSA).

Trait Implementations

impl AffineArithmetic for Secp256k1

type AffinePoint = AffinePoint

Elliptic curve point in affine coordinates.

impl AffineXCoordinate<Secp256k1> for AffinePoint

fn x(&self) -> FieldBytes

Get the affine x-coordinate as a serialized field element.

impl AssociatedOid for Secp256k1

const OID: ObjectIdentifier = pkcs8::ObjectIdentifier::new_unwrap("1.3.132.0.10")

The OID associated with this type.

impl Clone for Secp256k1

fn clone(&self) -> Secp256k1

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Curve for Secp256k1

type UInt = UInt<{_: usize}>

256-bit field modulus

const ORDER: U256 = ORDER

Curve order

impl Debug for Secp256k1

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

Formats the value using the given formatter.

impl DecompactPoint<Secp256k1> for AffinePoint

Decompaction using Taproot conventions as described in BIP 340.

fn decompact(x_bytes: &FieldBytes) -> CtOption<Self>

Attempt to decompact an elliptic curve point

impl DecompressPoint<Secp256k1> for AffinePoint

fn decompress(x_bytes: &FieldBytes, y_is_odd: Choice) -> CtOption<Self>

Attempt to decompress an elliptic curve point.

impl Default for Secp256k1

fn default() -> Secp256k1

Returns the “default value” for a type.

impl DigestPrimitive for Secp256k1

Available on crate features ecdsa-core and sha256 only.

type Digest = CoreWrapper<CtVariableCoreWrapper<Sha256VarCore, UInt<UInt<UInt<UInt<UInt<UInt<UTerm, B1>, B0>, B0>, B0>, B0>, B0>>>

Preferred digest to use when computing ECDSA signatures for this elliptic curve. This should be a member of the SHA-2 family.

impl FromEncodedPoint<Secp256k1> for AffinePoint

fn from_encoded_point(encoded_point: &EncodedPoint) -> CtOption<Self>

Attempts to parse the given EncodedPoint as an SEC1-encoded AffinePoint.

Returns

None value if encoded_point is not on the secp256k1 curve.

impl FromEncodedPoint<Secp256k1> for ProjectivePoint

fn from_encoded_point(p: &EncodedPoint) -> CtOption<Self>

Deserialize the type this trait is impl’d on from an EncodedPoint.

impl Ord for Secp256k1

fn cmp(&self, other: &Secp256k1) -> Ordering

This method returns an Ordering between self and other.

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

Compares and returns the maximum of two values.

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

Compares and returns the minimum of two values.

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

Restrict a value to a certain interval.

impl PartialEq<Secp256k1> for Secp256k1

fn eq(&self, other: &Secp256k1) -> bool

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=.

impl PartialOrd<Secp256k1> for Secp256k1

fn partial_cmp(&self, other: &Secp256k1) -> Option<Ordering>

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

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

This method tests less than (for self and other) and is used by the < operator.

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

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

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

This method tests greater than (for self and other) and is used by the > operator.

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

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

impl PointCompression for Secp256k1

const COMPRESS_POINTS: bool = true

secp256k1 points are typically compressed.

impl PrimeCurveArithmetic for Secp256k1

type CurveGroup = ProjectivePoint

Prime order elliptic curve group.

impl ProjectiveArithmetic for Secp256k1

type ProjectivePoint = ProjectivePoint

Elliptic curve point in projective coordinates.

impl ScalarArithmetic for Secp256k1

type Scalar = Scalar

Scalar field type.

impl SignPrimitive<Secp256k1> for Scalar

Available on crate feature ecdsa-core only.

fn try_sign_prehashed<K>(
    &self,
    ephemeral_scalar: K,
    z: FieldBytes
) -> Result<(Signature, Option<RecoveryId>), Error> where
    K: Borrow<Scalar> + Invert<Output = CtOption<Scalar>>, 

Try to sign the prehashed message.

fn try_sign_prehashed_rfc6979<D>(
    &self,
    z: GenericArray<u8, <<C as Curve>::UInt as ArrayEncoding>::ByteSize>,
    ad: &[u8]
) -> Result<(Signature<C>, Option<RecoveryId>), Error> where
    Self: From<ScalarCore<C>>,
    D: Digest<OutputSize = <<C as Curve>::UInt as ArrayEncoding>::ByteSize> + BlockSizeUser + FixedOutput + FixedOutputReset,
    <C as Curve>::UInt: for<'a> From<&'a Self>, 

Try to sign the given message digest deterministically using the method described in RFC6979 for computing ECDSA ephemeral scalar k.

fn try_sign_digest_rfc6979<D>(
    &self,
    msg_digest: D,
    ad: &[u8]
) -> Result<(Signature<C>, Option<RecoveryId>), Error> where
    Self: From<ScalarCore<C>>,
    D: Digest<OutputSize = <<C as Curve>::UInt as ArrayEncoding>::ByteSize> + BlockSizeUser + FixedOutput + FixedOutputReset,
    <C as Curve>::UInt: for<'a> From<&'a Self>, 

Try to sign the given digest instance using the method described in RFC6979.

impl ToEncodedPoint<Secp256k1> for AffinePoint

fn to_encoded_point(&self, compress: bool) -> EncodedPoint

Serialize this value as a SEC1 EncodedPoint, optionally applying point compression.

impl ToEncodedPoint<Secp256k1> for ProjectivePoint

fn to_encoded_point(&self, compress: bool) -> EncodedPoint

Serialize this value as a SEC1 EncodedPoint, optionally applying point compression.

impl ToEncodedPoint<Secp256k1> for VerifyingKey

Available on crate feature ecdsa-core only.

fn to_encoded_point(&self, compress: bool) -> EncodedPoint

Serialize this value as a SEC1 EncodedPoint, optionally applying point compression.

impl VerifyPrimitive<Secp256k1> for AffinePoint

Available on crate feature ecdsa-core only.

fn verify_prehashed(
    &self,
    z: FieldBytes,
    signature: &Signature
) -> Result<(), Error>

Verify the prehashed message against the provided signature

fn verify_digest<D>(
    &self,
    msg_digest: D,
    sig: &Signature<C>
) -> Result<(), Error> where
    D: FixedOutput<OutputSize = <<C as Curve>::UInt as ArrayEncoding>::ByteSize>, 

Verify message digest against the provided signature.

impl Copy for Secp256k1

impl Eq for Secp256k1

impl PrimeCurve for Secp256k1

impl StructuralEq for Secp256k1

impl StructuralPartialEq for Secp256k1