Trait oberon::inner_types::elliptic_curve::bigint::subtle::ConstantTimeLess

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pub trait ConstantTimeLess: ConstantTimeEq + ConstantTimeGreater {
    // Provided method
    fn ct_lt(&self, other: &Self) -> Choice { ... }
}

Expand description

A type which can be compared in some manner and be determined to be less than another of the same type.

Provided Methods§

source

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

Determine whether self < other.

The bitwise-NOT of the return value of this function should be usable to determine if self >= other.

A default implementation is provided and implemented for the unsigned integer types.

This function should execute in constant time.

Returns

A Choice with a set bit if self < other, and with no set bits otherwise.

Example

use subtle::ConstantTimeLess;

let x: u8 = 13;
let y: u8 = 42;

let x_lt_y = x.ct_lt(&y);

assert_eq!(x_lt_y.unwrap_u8(), 1);

let y_lt_x = y.ct_lt(&x);

assert_eq!(y_lt_x.unwrap_u8(), 0);

let x_lt_x = x.ct_lt(&x);

assert_eq!(x_lt_x.unwrap_u8(), 0);