Struct EdwardsPoint 

pub struct EdwardsPoint<F: FieldOps> {
    pub x: F,
    pub y: F,
}

An affine point on an Edwards curve, for any characteristic.

Fields

x: F

The x coordinate of a point.

y: F

The y coordinate of a point.

Implementations

impl<F: FieldOps> EdwardsPoint<F>

pub fn new(x: F, y: F) -> Self

Construct an affine Edwards point. No on-curve check.

pub fn identity() -> Self

The group identity.

• Odd char: (0, 1)
• Char 2: (0, 0)

pub fn is_identity(&self) -> bool

Check whether this is the identity element.

impl<F: FieldOps> EdwardsPoint<F>

pub fn negate(&self, _curve: &EdwardsCurve<F>) -> Self

Negate a point.

• Odd char: -(x, y) = (-x, y)
• Char 2: -(x, y) = (y, x)

pub fn add(&self, other: &Self, curve: &EdwardsCurve<F>) -> Self

Add two points on the Edwards curve.

pub fn double(&self, curve: &EdwardsCurve<F>) -> Self

Double a point. Both addition laws are strongly unified, so this just delegates to add.

pub fn scalar_mul(&self, k: &[u64], curve: &EdwardsCurve<F>) -> Self

Scalar multiplication [k]P (constant-time double-and-add).

impl<F: FieldOps> EdwardsPoint<F>

pub fn w_diff_add(w1: &F, w2: &F, w3: &F, curve: &EdwardsCurve<F>) -> F

Differential addition on the w-line (w = x + y, char 2 only).

Given w₁ = w(Q−P), w₂ = w(P), w₃ = w(Q), compute w₅ = w(P+Q).

pub fn w_double(w2: &F, curve: &EdwardsCurve<F>) -> F

w-coordinate doubling (w = x + y, char 2 only).

Given w₂ = w(P), compute w₄ = w(2P).

Trait Implementations

impl<F: Clone + FieldOps> Clone for EdwardsPoint<F>

fn clone(&self) -> EdwardsPoint<F>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<F> ConditionallySelectable for EdwardsPoint<F>

where F: FieldOps + Copy,

fn conditional_select(a: &Self, b: &Self, choice: Choice) -> Self

Select a or b according to choice.

fn conditional_assign(&mut self, other: &Self, choice: Choice)

Conditionally assign other to self, according to choice.

fn conditional_swap(a: &mut Self, b: &mut Self, choice: Choice)

Conditionally swap self and other if choice == 1; otherwise, reassign both unto themselves.

impl<F> ConstantTimeEq for EdwardsPoint<F>

where F: FieldOps + Copy + ConstantTimeEq,

fn ct_eq(&self, other: &Self) -> Choice

Determine if two items are equal.

fn ct_ne(&self, other: &Self) -> Choice

Determine if two items are NOT equal.

impl<F: Debug + FieldOps> Debug for EdwardsPoint<F>

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

Formats the value using the given formatter.

impl<F> Display for EdwardsPoint<F>

where F: FieldOps + Display,

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

Formats the value using the given formatter.

impl<F: FieldOps> PartialEq for EdwardsPoint<F>

fn eq(&self, other: &Self) -> 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<F: FieldOps> PointOps for EdwardsPoint<F>

type BaseField = F

The base field $\mathbb{F}_{p^M}$

type Curve = EdwardsCurve<F>

The elliptic curve we’re working on

fn identity(_curve: &Self::Curve) -> Self

Returns the identity

fn is_identity(&self) -> bool

Returns true if and only if self is the identity

fn negate(&self, curve: &Self::Curve) -> Self

Negate a point

fn scalar_mul(&self, k: &[u64], curve: &Self::Curve) -> Self

Scalar multiplication [k]P (variable-time double-and-add).

impl<F: Copy + FieldOps> Copy for EdwardsPoint<F>

impl<F: FieldOps> Eq for EdwardsPoint<F>