package mec

  1. Overview
  2. Docs
package mec
Legend:
Library
Module
Module type
Parameter
Class
Class type

by^2 = x3 + ax^2 + x with b * (a^2 - 4) != 0

include Mec_curve_sig.Ec_sig.MontgomeryT
include Mec_curve_sig.Ec_sig.BASE
exception Not_on_curve of Stdlib.Bytes.t
type t

Represents an element on the curve. In the case of a curve with a cofactor, the element is not necessarily in the prime subgroup.

val size_in_bytes : int

The size of a point representation, in bytes

module Scalar : Ff_sig.PRIME
module Base : Ff_sig.PRIME
val check_bytes : Stdlib.Bytes.t -> bool

Check if a point, represented as a byte array, is on the curve *

val of_bytes_opt : Stdlib.Bytes.t -> t option

Attempt to construct a point from a byte array

val of_bytes_exn : Stdlib.Bytes.t -> t

Attempt to construct a point from a byte array. Raise Not_on_curve if the point is not on the curve

val to_bytes : t -> Stdlib.Bytes.t

Return a representation in bytes

val zero : t

Zero of the elliptic curve

val one : t

A fixed generator of the elliptic curve

val is_zero : t -> bool

Return true if the given element is zero

val random : ?state:Stdlib.Random.State.t -> unit -> t

Generate a random element

val add : t -> t -> t

Return the addition of two element

val double : t -> t

Double the element

val negate : t -> t

Return the opposite of the element

val eq : t -> t -> bool

Return true if the two elements are algebraically the same

val mul : t -> Scalar.t -> t

Multiply an element by a scalar

val a : Base.t
val b : Base.t
val cofactor : Z.t
val is_on_curve : x:Base.t -> y:Base.t -> bool

is_on_curve ~x ~y returns true if the coordinates (x, y) represents a point on the curve. It does not check the point is in the prime subgroup.

val is_in_prime_subgroup : x:Base.t -> y:Base.t -> bool

is_in_prime_subgroup ~x ~y returns true if the coordinates (x, y) represents a point in the prime subgroup. The coordinates must be a point on the curve

val get_x_coordinate : t -> Base.t
val get_y_coordinate : t -> Base.t
val to_twisted_curve_parameters : unit -> (Base.t * Base.t * Z.t * (Base.t * Base.t)) option
val to_twisted : t -> (Base.t * Base.t) option
val to_weierstrass_curve_parameters : unit -> (Base.t * Base.t * Z.t * (Base.t * Base.t)) option
val to_weierstrass : t -> (Base.t * Base.t) option
val from_coordinates_opt : x:Base.t -> y:Base.t -> t option

Build a point from the affine coordinates. If the point is not on the curve and in the subgroup, returns None

val from_coordinates_exn : x:Base.t -> y:Base.t -> t

Build a point from the affine coordinates. If the point is not on the curve and in the subgroup, raise Not_on_curve.

val of_compressed_bytes_exn : Stdlib.Bytes.t -> t

Build a point from a compressed representation. It supposes the base field leaves at least a free bit in the last byte to encode the sign. Raise Not_on_curve if the bytes do not represent a point on the curve and in the prime subgroup.

val of_compressed_bytes_opt : Stdlib.Bytes.t -> t option

Same than of_compressed_bytes_exn but returns an option instead of raising an exception

val to_compressed_bytes : t -> Stdlib.Bytes.t

Return the compressed representation of the point

OCaml

Innovation. Community. Security.

GitHub Discord Twitter Peertube RSS
About
Changelog Releases Industrial Users Academic Users Why OCaml
Ecosystem
Packages Community Events OCaml Planet Jobs
Resources
Install OCaml Get Started Platform Tools Language Manual Standard Library API Books Exercises Papers OCaml Playground Logo
Policies
Carbon Footprint Governance Privacy Code of Conduct