Struct salty::CompressedY

[+] Show declaration

pub struct CompressedY(pub [u8; 32]);

[−] Expand description

"Compressed" form of a CurvePoint, whereby the sign of the x-coordinate is stuffed in a spare bit of the y-coordinate

Methods

impl CompressedY[−]

pub fn decompressed(&self) -> Result<CurvePoint>[−]

This is rather tricky: to get the x-coordinate, and not just its sign, need to calculate the square root of u/v := (y**2 - 1)/(dy**2 + 1). Moreover, we want to detect whether our compressed Y actually corresponds to a point on the curve! The original sources are the Tweet NaCl paper, section 5 and the ed25519 paper, also section 5.

impl CompressedY[−]

pub fn as_bytes(&self) -> &[u8; 32]

pub fn to_bytes(&self) -> [u8; 32]

Trait Implementations

impl<'_> From<&'_ [u8; 32]> for CompressedY[+]

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fn from(bytes: &[u8; 32]) -> CompressedY[−]

Performs the conversion.

impl PartialEq<CompressedY> for CompressedY[+]

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fn eq(&self, other: &Self) -> bool[−]

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

[+] Expand attributes

#[must_use] fn ne(&self, other: &Rhs) -> bool[−]

This method tests for !=.

impl Debug for CompressedY[+]

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fn fmt(&self, f: &mut Formatter) -> Result[−]

Formats the value using the given formatter.

impl Copy for CompressedY

impl Clone for CompressedY[+]

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fn clone(&self) -> CompressedY[−]

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)[−]

Performs copy-assignment from source.

impl Default for CompressedY[+]

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fn default() -> CompressedY[−]

Returns the "default value" for a type.

impl ConstantTimeEq for CompressedY[+]

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

Determine if two items are equal.