Crypto.PubKey.ECC.P256

A P256 scalar

A P256 point

Get the base point for the P256 Curve

Add a point to another point

Negate a point

Multiply a point by a scalar

warning: variable time

Similar to pointMul, serializing the x coordinate as binary. When scalar is multiple of point order the result is all zero.

multiply the point p with n2 and add a lifted to curve value @n1

n1 * G + n2 * p

warning: variable time

Check if a Point is valid

Check if a Point is the point at infinity

Lift to curve a scalar

Using the curve generator as base point compute:

scalar * G

Return the x coordinate as a Scalar if the point is not at infinity

Convert a point to (x,y) Integers

Convert from (x,y) Integers to a point

Convert a point to a binary representation

Convert from binary to a valid point

Convert from binary to a point, possibly invalid

Generate a randomly generated new scalar

The scalar representing 0

The scalar representing the curve order

Check if the scalar is 0

Bring a scalar below the order of the curve

scalarFromInteger and scalarFromBinary take any 256 bits, so a scalar can arrive above the order; the arithmetic below wants it brought down first. Twice the order is more than 256 bits hold, so this is a single subtraction, taken or not through a mask rather than a branch.

Perform addition between two scalars

a + b

Perform subtraction between two scalars

a - b

Perform multiplication between two scalars

a * b

Give the inverse of the scalar

1 / a

warning: variable time

Give the inverse of the scalar using safe exponentiation

1 / a

Compare 2 Scalar

convert a scalar from binary

convert a scalar to binary

Convert from an Integer to a P256 Scalar

Convert from a P256 Scalar to an Integer