Struct curve25519_dalek::edwards::EdwardsPoint [−][src]
An EdwardsPoint
represents a point on the Edwards form of Curve25519.
Implementations
impl EdwardsPoint
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pub fn to_montgomery(&self) -> MontgomeryPoint
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Convert this EdwardsPoint
on the Edwards model to the
corresponding MontgomeryPoint
on the Montgomery model.
This function has one exceptional case; the identity point of the Edwards curve is sent to the 2-torsion point \((0,0)\) on the Montgomery curve.
Note that this is a one-way conversion, since the Montgomery model does not retain sign information.
pub fn compress(&self) -> CompressedEdwardsY
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Compress this point to CompressedEdwardsY
format.
impl EdwardsPoint
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pub fn vartime_double_scalar_mul_basepoint(
a: &Scalar,
A: &EdwardsPoint,
b: &Scalar
) -> EdwardsPoint
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a: &Scalar,
A: &EdwardsPoint,
b: &Scalar
) -> EdwardsPoint
Compute \(aA + bB\) in variable time, where \(B\) is the Ed25519 basepoint.
impl EdwardsPoint
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pub fn mul_by_cofactor(&self) -> EdwardsPoint
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Multiply by the cofactor: return \([8]P\).
pub fn is_small_order(&self) -> bool
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Determine if this point is of small order.
Return
true
ifself
is in the torsion subgroup \( \mathcal E[8] \);false
ifself
is not in the torsion subgroup \( \mathcal E[8] \).
Example
use curve25519_dalek::constants; // Generator of the prime-order subgroup let P = constants::ED25519_BASEPOINT_POINT; // Generator of the torsion subgroup let Q = constants::EIGHT_TORSION[1]; // P has large order assert_eq!(P.is_small_order(), false); // Q has small order assert_eq!(Q.is_small_order(), true);
pub fn is_torsion_free(&self) -> bool
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Determine if this point is “torsion-free”, i.e., is contained in the prime-order subgroup.
Return
true
ifself
has zero torsion component and is in the prime-order subgroup;false
ifself
has a nonzero torsion component and is not in the prime-order subgroup.
Example
use curve25519_dalek::constants; // Generator of the prime-order subgroup let P = constants::ED25519_BASEPOINT_POINT; // Generator of the torsion subgroup let Q = constants::EIGHT_TORSION[1]; // P is torsion-free assert_eq!(P.is_torsion_free(), true); // P + Q is not torsion-free assert_eq!((P+Q).is_torsion_free(), false);
Trait Implementations
impl<'a, 'b> Add<&'b EdwardsPoint> for &'a EdwardsPoint
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impl<'b> Add<&'b EdwardsPoint> for EdwardsPoint
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impl<'a> Add<EdwardsPoint> for &'a EdwardsPoint
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impl Add<EdwardsPoint> for EdwardsPoint
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impl<'b> AddAssign<&'b EdwardsPoint> for EdwardsPoint
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impl AddAssign<EdwardsPoint> for EdwardsPoint
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impl Clone for EdwardsPoint
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impl ConditionallySelectable for EdwardsPoint
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impl ConstantTimeEq for EdwardsPoint
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impl Copy for EdwardsPoint
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impl Debug for EdwardsPoint
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impl Default for EdwardsPoint
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impl Eq for EdwardsPoint
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impl Identity for EdwardsPoint
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impl<'b> Mul<&'b EdwardsPoint> for Scalar
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impl<'a, 'b> Mul<&'b EdwardsPoint> for &'a Scalar
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impl<'b> Mul<&'b Scalar> for EdwardsPoint
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impl<'a, 'b> Mul<&'b Scalar> for &'a EdwardsPoint
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impl<'a> Mul<EdwardsPoint> for &'a Scalar
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impl Mul<EdwardsPoint> for Scalar
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impl<'a> Mul<Scalar> for &'a EdwardsPoint
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impl Mul<Scalar> for EdwardsPoint
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impl<'b> MulAssign<&'b Scalar> for EdwardsPoint
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impl MulAssign<Scalar> for EdwardsPoint
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impl MultiscalarMul for EdwardsPoint
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impl<'a> Neg for &'a EdwardsPoint
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impl Neg for EdwardsPoint
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impl PartialEq<EdwardsPoint> for EdwardsPoint
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impl<'a, 'b> Sub<&'b EdwardsPoint> for &'a EdwardsPoint
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impl<'b> Sub<&'b EdwardsPoint> for EdwardsPoint
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impl<'a> Sub<EdwardsPoint> for &'a EdwardsPoint
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impl Sub<EdwardsPoint> for EdwardsPoint
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impl<'b> SubAssign<&'b EdwardsPoint> for EdwardsPoint
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impl SubAssign<EdwardsPoint> for EdwardsPoint
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impl<T> Sum<T> for EdwardsPoint where
T: Borrow<EdwardsPoint>,
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T: Borrow<EdwardsPoint>,
impl VartimeMultiscalarMul for EdwardsPoint
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Auto Trait Implementations
impl RefUnwindSafe for EdwardsPoint
impl Send for EdwardsPoint
impl Sync for EdwardsPoint
impl Unpin for EdwardsPoint
impl UnwindSafe for EdwardsPoint
Blanket Implementations
impl<T> Any for T where
T: 'static + ?Sized,
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T: 'static + ?Sized,
impl<T> Borrow<T> for T where
T: ?Sized,
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T: ?Sized,
impl<T> BorrowMut<T> for T where
T: ?Sized,
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T: ?Sized,
impl<T> ConditionallyNegatable for T where
T: ConditionallySelectable,
&'a T: for<'a> Neg,
<&'a T as Neg>::Output == T,
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T: ConditionallySelectable,
&'a T: for<'a> Neg,
<&'a T as Neg>::Output == T,
impl<T> From<T> for T
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impl<T, U> Into<U> for T where
U: From<T>,
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U: From<T>,
impl<T> IsIdentity for T where
T: ConstantTimeEq + Identity,
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T: ConstantTimeEq + Identity,
impl<T> Same<T> for T
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type Output = T
Should always be Self
impl<T> ToOwned for T where
T: Clone,
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T: Clone,
impl<T, U> TryFrom<U> for T where
U: Into<T>,
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U: Into<T>,
impl<T, U> TryInto<U> for T where
U: TryFrom<T>,
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U: TryFrom<T>,