Struct p256::Scalar

pub struct Scalar(_);

This is supported on feature="arithmetic" only.

An element in the finite field modulo n.

Implementations

impl Scalar

pub const fn zero() -> Scalar

Returns the zero scalar.

pub const fn one() -> Scalar

Returns the multiplicative identity.

pub fn from_secret_key(s: &SecretKey) -> CtOption<Scalar>

Attempts to convert a SecretKey (defined in the more generic elliptic_curve crate) to a Scalar

Returns None if the secret's underlying value does not represent a field element.

pub fn from_bytes_reduced(bytes: &ElementBytes) -> Self

Parses the given byte array as a scalar.

Subtracts the modulus when the byte array is larger than the modulus.

pub fn is_zero(&self) -> Choice

Determine if this Scalar is zero.

Returns

If zero, return Choice(1). Otherwise, return Choice(0).

pub const fn add(&self, rhs: &Self) -> Self

Returns self + rhs mod n

pub const fn double(&self) -> Self

Returns 2*self.

pub const fn subtract(&self, rhs: &Self) -> Self

Returns self - rhs mod n

pub const fn mul(&self, rhs: &Self) -> Self

Returns self * rhs mod n

pub const fn square(&self) -> Self

Returns self * self mod p

pub fn pow_vartime(&self, by: &[u64; 4]) -> Self

Returns self^by, where by is a little-endian integer exponent.

This operation is variable time with respect to the exponent. If the exponent is fixed, this operation is effectively constant time.

pub fn invert(&self) -> CtOption<Self>

Returns the multiplicative inverse of self, if self is non-zero

pub fn is_odd(&self) -> Choice

Is integer representing equivalence class odd

pub fn is_even(&self) -> Choice

Is integer representing equivalence class even

pub fn invert_vartime(&self) -> CtOption<Self>

Faster inversion using Stein's algorithm

Trait Implementations

impl<'_, '_> Add<&'_ Scalar> for &'_ Scalar

type Output = Scalar

The resulting type after applying the + operator.

fn add(self, other: &Scalar) -> Scalar

Performs the + operation.

impl<'_> Add<&'_ Scalar> for Scalar

type Output = Scalar

The resulting type after applying the + operator.

fn add(self, other: &Scalar) -> Scalar

Performs the + operation.

impl AddAssign<Scalar> for Scalar

fn add_assign(&mut self, rhs: Scalar)

Performs the += operation.

impl Borrow<Scalar> for BlindedScalar

fn borrow(&self) -> &Scalar

Immutably borrows from an owned value.

impl Clone for Scalar

fn clone(&self) -> Scalar

Returns a copy of the value.

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

Performs copy-assignment from source.

impl ConditionallySelectable for Scalar

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 ConstantTimeEq for Scalar

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

Determine if two items are equal.

impl Copy for Scalar

impl Debug for Scalar

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

Formats the value using the given formatter.

impl Default for Scalar

fn default() -> Scalar

Returns the "default value" for a type.

impl Eq for Scalar

impl From<Scalar> for ElementBytes

fn from(scalar: Scalar) -> Self

Performs the conversion.

impl From<u64> for Scalar

fn from(k: u64) -> Self

Performs the conversion.

impl FromBytes for Scalar

type Size = U32

Size of the serialized byte array

fn from_bytes(bytes: &ElementBytes) -> CtOption<Self>

Attempts to parse the given byte array as an SEC-1-encoded scalar.

Returns None if the byte array does not contain a big-endian integer in the range [0, p).

impl Generate for Scalar

fn generate(rng: impl CryptoRng + RngCore) -> Self

Generate a random element of this type using the provided [CryptoRng]

impl Invert for Scalar

type Output = Self

Field element type

fn invert(&self) -> CtOption<Self>

Invert a field element.

impl<'_, '_> Mul<&'_ Scalar> for &'_ Scalar

type Output = Scalar

The resulting type after applying the * operator.

fn mul(self, other: &Scalar) -> Scalar

Performs the * operation.

impl<'_> Mul<&'_ Scalar> for Scalar

type Output = Scalar

The resulting type after applying the * operator.

fn mul(self, other: &Scalar) -> Scalar

Performs the * operation.

impl<'_, '_> Mul<&'_ Scalar> for &'_ ProjectivePoint

type Output = ProjectivePoint

The resulting type after applying the * operator.

fn mul(self, other: &Scalar) -> ProjectivePoint

Performs the * operation.

impl<'_> Mul<&'_ Scalar> for ProjectivePoint

type Output = ProjectivePoint

The resulting type after applying the * operator.

fn mul(self, other: &Scalar) -> ProjectivePoint

Performs the * operation.

impl<'_> MulAssign<&'_ Scalar> for ProjectivePoint

fn mul_assign(&mut self, rhs: &Scalar)

Performs the *= operation.

impl MulAssign<Scalar> for Scalar

fn mul_assign(&mut self, rhs: Scalar)

Performs the *= operation.

impl MulAssign<Scalar> for ProjectivePoint

fn mul_assign(&mut self, rhs: Scalar)

Performs the *= operation.

impl Neg for Scalar

type Output = Scalar

The resulting type after applying the - operator.

fn neg(self) -> Scalar

Performs the unary - operation.

impl<'a> Neg for &'a Scalar

type Output = Scalar

The resulting type after applying the - operator.

fn neg(self) -> Scalar

Performs the unary - operation.

impl Ord for Scalar

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

This method returns an [Ordering] between self and other.

#[must_use]fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

#[must_use]fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

#[must_use]fn clamp(self, min: Self, max: Self) -> Self

🔬 This is a nightly-only experimental API. (clamp)

Restrict a value to a certain interval.

impl PartialEq<Scalar> for Scalar

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

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

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

This method tests for !=.

impl PartialOrd<Scalar> for Scalar

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

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

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

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

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

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

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

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

#[must_use]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 SignPrimitive<NistP256> for Scalar

fn try_sign_prehashed<K>(
    &self,
    ephemeral_scalar: &K,
    hashed_msg: &ElementBytes
) -> Result<Signature, Error> where
    K: Borrow<Scalar> + Invert<Output = Scalar>, 

Try to sign the prehashed message.

impl<'_, '_> Sub<&'_ Scalar> for &'_ Scalar

type Output = Scalar

The resulting type after applying the - operator.

fn sub(self, other: &Scalar) -> Scalar

Performs the - operation.

impl<'_> Sub<&'_ Scalar> for Scalar

type Output = Scalar

The resulting type after applying the - operator.

fn sub(self, other: &Scalar) -> Scalar

Performs the - operation.

impl SubAssign<Scalar> for Scalar

fn sub_assign(&mut self, rhs: Scalar)

Performs the -= operation.

impl Zeroize for Scalar

fn zeroize(&mut self)

Zero out this object from memory using Rust intrinsics which ensure the zeroization operation is not "optimized away" by the compiler.