Struct k256::ecdsa::RecoveryId

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

Recovery IDs, a.k.a. “recid”.

This is an integer value 0, 1, 2, or 3 included along with a signature which is used during the recovery process to select the correct public key from the signature.

It consists of two bits of information:

• low bit (0/1): was the y-coordinate of the affine point resulting from the fixed-base multiplication 𝑘×𝑮 odd? This part of the algorithm functions similar to point decompression.
• hi bit (3/4): did the affine x-coordinate of 𝑘×𝑮 overflow the order of the scalar field, requiring a reduction when computing r?

Implementations

impl RecoveryId

pub const MAX: u8 = 3u8

Maximum supported value for the recovery ID (inclusive).

pub const fn new(is_y_odd: bool, is_x_reduced: bool) -> RecoveryId

Create a new RecoveryId from the following 1-bit arguments:

• is_y_odd: is the affine y-coordinate of 𝑘×𝑮 odd?
• is_x_reduced: did the affine x-coordinate of 𝑘×𝑮 overflow the curve order?

pub const fn is_x_reduced(self) -> bool

Did the affine x-coordinate of 𝑘×𝑮 overflow the curve order?

pub const fn is_y_odd(self) -> bool

Is the affine y-coordinate of 𝑘×𝑮 odd?

pub const fn from_byte(byte: u8) -> Option<RecoveryId>

Convert a u8 into a RecoveryId.

pub const fn to_byte(self) -> u8

Convert this RecoveryId into a u8.

impl RecoveryId

pub fn trial_recovery_from_msg<C>( verifying_key: &VerifyingKey<C>, msg: &[u8], signature: &Signature<C>, ) -> Result<RecoveryId, Error>

where C: DigestPrimitive + PrimeCurve + CurveArithmetic, <C as CurveArithmetic>::AffinePoint: DecompressPoint<C> + FromEncodedPoint<C> + ToEncodedPoint<C> + VerifyPrimitive<C>, <C as Curve>::FieldBytesSize: ModulusSize, <<C as Curve>::FieldBytesSize as Add>::Output: ArrayLength<u8>,

Given a public key, message, and signature, use trial recovery to determine if a suitable recovery ID exists, or return an error otherwise.

pub fn trial_recovery_from_digest<C, D>( verifying_key: &VerifyingKey<C>, digest: D, signature: &Signature<C>, ) -> Result<RecoveryId, Error>

where C: PrimeCurve + CurveArithmetic, D: Digest, <C as CurveArithmetic>::AffinePoint: DecompressPoint<C> + FromEncodedPoint<C> + ToEncodedPoint<C> + VerifyPrimitive<C>, <C as Curve>::FieldBytesSize: ModulusSize, <<C as Curve>::FieldBytesSize as Add>::Output: ArrayLength<u8>,

Given a public key, message digest, and signature, use trial recovery to determine if a suitable recovery ID exists, or return an error otherwise.

pub fn trial_recovery_from_prehash<C>( verifying_key: &VerifyingKey<C>, prehash: &[u8], signature: &Signature<C>, ) -> Result<RecoveryId, Error>

where C: PrimeCurve + CurveArithmetic, <C as CurveArithmetic>::AffinePoint: DecompressPoint<C> + FromEncodedPoint<C> + ToEncodedPoint<C> + VerifyPrimitive<C>, <C as Curve>::FieldBytesSize: ModulusSize, <<C as Curve>::FieldBytesSize as Add>::Output: ArrayLength<u8>,

Given a public key, message digest, and signature, use trial recovery to determine if a suitable recovery ID exists, or return an error otherwise.

Trait Implementations

impl Clone for RecoveryId

fn clone(&self) -> RecoveryId

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for RecoveryId

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

Formats the value using the given formatter.

impl Ord for RecoveryId

fn cmp(&self, other: &RecoveryId) -> 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 + PartialOrd,

Restrict a value to a certain interval.

impl PartialEq for RecoveryId

fn eq(&self, other: &RecoveryId) -> 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 !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for RecoveryId

fn partial_cmp(&self, other: &RecoveryId) -> 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 TryFrom<u8> for RecoveryId

type Error = Error

The type returned in the event of a conversion error.

fn try_from(byte: u8) -> Result<RecoveryId, Error>

Performs the conversion.

impl Copy for RecoveryId

impl Eq for RecoveryId

impl StructuralPartialEq for RecoveryId