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use crate::{
backend::{self, BackendPoint, TimeSensitive},
hash::HashInto,
marker::*,
op, Scalar,
};
use core::{
marker::PhantomData,
ops::{AddAssign, SubAssign},
};
use rand_core::RngCore;
/// A point on the secp256k1 elliptic curve.
///
/// A `Point<T,S,Z>` marked with `Z = NonZero` is any two integers modulo `p` `(x,y)` that satisfy:
///
/// `y^2 = 3*x + 7 mod p`
///
/// where `p = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFC2F`.
/// For every valid x-coordinate, there will be exactly two valid y-coordinates which will be the negation modulo p of each other.
///
/// If the point is marked `Z = Zero` then it may also be _point at infinity_ which is the [_identity element_] of the group.
///
/// ## Markers
///
/// A `Point<T,S,Z>` has three types parameters.
///
/// - `T`: A [`PointType`] used to reason about what the point can do and to specialize point operations.
/// - `S`: A [`Secrecy`] to determine whether operations on this point should be done in constant-time or not. By default points are [`Public`] so operations run in variable time.
/// - `Z`: A [`ZeroChoice`] to keep track of whether the point might be zero (the point at infinity) or is guaranteed to be non-zero.
///
/// ## Serialization
///
/// Only points that are normalized (i.e. `T` ≠ `NonNormal`) can be serialized. A Point that is
/// `EvenY` points serialize to and from their 32-byte x-only representation.
/// `Normal` points serialize to and from the standard 33-byte representation specified in
/// [_Standards for Efficient Cryptography_] (the same as [`Point::to_bytes`]). Points that are
/// are zero (see [`is_zero`]) will serialize to `[0u8;33]`.
///
///
/// [_Standards for Efficient Cryptography_]: https://www.secg.org/sec1-v2.pdf
/// [`Point::to_bytes`]: crate::Point::to_bytes
/// [`PointType`]: crate::marker::PointType
/// [`Secrecy`]: crate::marker::Secrecy
/// [`ZeroChoice`]: crate::marker::ZeroChoice
/// [`Public`]: crate::marker::Public
/// [`is_zero`]: crate::Point::is_zero
/// [_identity element_]: https://en.wikipedia.org/wiki/Identity_element
pub struct Point<T = Normal, S = Public, Z = NonZero>(
pub(crate) backend::Point,
pub(crate) T,
PhantomData<(Z, S)>,
);
/// The default for `Point`<_,_,Zero>` is [`Point::zero`].
impl<T: Default, S> Default for Point<T, S, Zero> {
fn default() -> Self {
Point::zero()
}
}
/// The default for `Point`<_,_,Zero>` is [`Point::generator`].
impl<T: Default + PointType, S> Default for Point<T, S, NonZero> {
fn default() -> Self {
Point::generator()
}
}
impl<Z, S, T: Clone> Clone for Point<T, S, Z> {
fn clone(&self) -> Self {
Point::from_inner(self.0, self.1.clone())
}
}
impl<T, S, Z> AsRef<backend::Point> for Point<T, S, Z> {
fn as_ref(&self) -> &backend::Point {
&self.0
}
}
impl<T: Copy, S, Z> Copy for Point<T, S, Z> {}
impl Point<Normal, Public, NonZero> {
/// Samples a point uniformly from the group.
///
/// # Examples
///
/// Generate a random point from `thread_rng`.
/// ```
/// # use secp256kfun::Point;
/// let random_point = Point::random(&mut rand::thread_rng());
pub fn random(rng: &mut impl RngCore) -> Self {
let mut bytes = [0u8; 33];
rng.fill_bytes(&mut bytes[..]);
bytes[0] &= 0x01;
bytes[0] |= 0x02;
Self::from_bytes(bytes).unwrap_or_else(|| Self::random(rng))
}
/// Creates a Point from a 65-byte uncompressed encoding specified in
/// [_Standards for Efficient Cryptography_]. The first byte must be
/// `0x04`. The remaining 64 bytes must encode a valid x and y coordinate
/// on the curve. If the conditions are not met then it will return `None`.
///
/// [_Standards for Efficient Cryptography_]: https://www.secg.org/sec1-v2.pdf
pub fn from_bytes_uncompressed(bytes: [u8; 65]) -> Option<Self> {
if bytes[0] != 0x04 {
return None;
}
let mut x = [0u8; 32];
let mut y = [0u8; 32];
x.copy_from_slice(&bytes[1..33]);
y.copy_from_slice(&bytes[33..65]);
backend::Point::norm_from_coordinates(x, y).map(|p| Point::from_inner(p, Normal))
}
}
impl<Z: ZeroChoice, S> Point<Normal, S, Z> {
/// Creates a Point the compressed encoding specified in [_Standards for
/// Efficient Cryptography_]. This is the typical encoding used in
/// Bitcoin. The first byte must be `0x02` or `0x03` to indicate that the
/// y-coordinate is even or odd respectively. The remaining 32 bytes must
/// encode an x-coordinate on the curve. If these conditions are not then
/// it will return `None`.
///
/// # Examples
/// ```
/// use secp256kfun::{marker::*, Point, G};
/// let bytes = [
/// 2, 121, 190, 102, 126, 249, 220, 187, 172, 85, 160, 98, 149, 206, 135, 11, 7, 2, 155, 252,
/// 219, 45, 206, 40, 217, 89, 242, 129, 91, 22, 248, 23, 152,
/// ];
/// let point = Point::<_, Public, NonZero>::from_bytes(bytes).unwrap();
/// assert_eq!(point, *G);
/// ```
///
/// [_Standards for Efficient Cryptography_]: https://www.secg.org/sec1-v2.pdf
pub fn from_bytes(bytes: [u8; 33]) -> Option<Self> {
if Z::is_zero() && bytes == [0u8; 33] {
return Some(Point::from_inner(backend::Point::zero(), Normal));
}
let y_odd = match bytes[0] {
2 => false,
3 => true,
_ => return None,
};
let mut x_bytes = [0u8; 32];
x_bytes.copy_from_slice(&bytes[1..]);
backend::Point::norm_from_bytes_y_oddness(x_bytes, y_odd)
.map(|p| Point::from_inner(p, Normal))
}
/// Convenience method for calling [`from_bytes`] wth a slice.
/// Returns None if [`from_bytes`] would or if `slice` is not 33 bytes long.
///
/// [`from_bytes`]: Self::from_bytes
pub fn from_slice(slice: &[u8]) -> Option<Self> {
if slice.len() != 33 {
return None;
}
let mut bytes = [0u8; 33];
bytes.copy_from_slice(slice);
Self::from_bytes(bytes)
}
}
impl<T, S> Point<T, S, NonZero> {
/// Converts this point into the point with the same x-coordinate but with
/// an even y-coordinate. Returns a Point marked `EvenY` with a `bool`
/// indicating whether the point had to be negated to make its y-coordinate
/// even.
///
/// # Examples
/// ```
/// use secp256kfun::{marker::*, Point};
/// let point = Point::random(&mut rand::thread_rng());
/// let (point_with_even_y, was_odd) = point.clone().into_point_with_even_y();
/// ```
pub fn into_point_with_even_y(self) -> (Point<EvenY, S, NonZero>, bool)
where
T: PointType,
{
let normalized = self.normalize();
let needs_negation = !normalized.is_y_even();
let negated = normalized.conditional_negate(needs_negation);
(Point::from_inner(negated.0, EvenY), needs_negation)
}
/// Returns the generator point [`G`] defined in [_Standards for Efficient Cryptography_].
///
/// This is sometimes more useful than just using `secp256kfun::G` since it allows the compiler
/// to infer types.
///
/// ## Examples
///
/// ```
/// use secp256kfun::{marker::*, Point, G};
/// assert_eq!(Point::<Normal, Public, _>::generator(), *G);
/// ```
///
/// [_Standards for Efficient Cryptography_]: https://www.secg.org/sec1-v2.pdf
/// [`G`]: crate::G
pub fn generator() -> Self
where
T: Default,
{
Self::from_inner(backend::G_POINT, T::default())
}
}
impl Point<EvenY, Public, NonZero> {
/// Multiplies `base` by `scalar` and returns the resulting point. If the
/// resulting point does not have an even y-coordinate then the scalar and
/// point are negated so the point has an even y-coordinate and the scalar
/// matches it.
///
/// # Examples
///
/// ```
/// use secp256kfun::{marker::*, Point, Scalar, G};
/// let mut secret_key = Scalar::random(&mut rand::thread_rng());
/// let public_key = Point::even_y_from_scalar_mul(G, &mut secret_key);
/// assert!(public_key.is_y_even());
/// ```
pub fn even_y_from_scalar_mul(
base: &Point<impl PointType, impl Secrecy>,
scalar: &mut Scalar<impl Secrecy>,
) -> Self {
let point = crate::op::scalar_mul_point(*scalar, base);
let (point, needs_negation) = point.into_point_with_even_y();
scalar.conditional_negate(needs_negation);
point
}
}
impl<T, S, Z> Point<T, S, Z> {
/// Returns true if this point the [`identity element`] of the group A.K.A. the point at infinity.
///
/// [`identity_element`]: https://en.wikipedia.org/wiki/Identity_element
///
/// # Examples
/// ```
/// # use secp256kfun::{ Point, g};
/// let point = Point::random(&mut rand::thread_rng());
/// assert!(!point.is_zero());
/// assert!(g!(0 * point).is_zero());
/// ```
pub fn is_zero(&self) -> bool {
backend::BackendPoint::is_zero(&self.0)
}
pub(crate) const fn from_inner(backend_point: backend::Point, point_type: T) -> Self {
Point(backend_point, point_type, PhantomData)
}
/// Negates a point based on a condition.
/// If `cond` is true the value returned is the negation of the point, otherwise it will be the point.
#[must_use]
pub fn conditional_negate(&self, cond: bool) -> Point<T::NegationType, S, Z>
where
T: PointType,
{
op::point_conditional_negate(*self, cond)
}
/// Set the [`Secrecy`] of the point.
pub fn set_secrecy<SNew>(self) -> Point<T, SNew, Z> {
Point::from_inner(self.0, self.1)
}
/// Set the [`Secrecy`] of the point to [`Public`].
///
/// Note that points are by default `Public`.
///
/// [`Secrecy`]: crate::marker::Secrecy
/// [`Public`]: crate::marker::Public
pub fn public(self) -> Point<T, Public, Z> {
Point::from_inner(self.0, self.1)
}
/// Set the [`Secrecy`] of the point to [`Secret`].
///
/// [`Secrecy`]: crate::marker::Secrecy
/// [`Public`]: crate::marker::Public
pub fn secret(self) -> Point<T, Secret, Z> {
Point::from_inner(self.0, self.1)
}
/// Normalize a point.
///
/// This is usually only useful to do if the `Point` is marked as [`NonNormal`].
/// Otherwise it will be no-op and just set the [`PointType`] to [`Normal`].
///
/// [`NonNormal`]: crate::marker::NonNormal
/// [`PointType`]: crate::marker::PointType
/// [`Normal`]: crate::marker::Normal
pub fn normalize(self) -> Point<Normal, S, Z>
where
T: PointType,
{
op::point_normalize(self)
}
/// Mark the point as being [`NonNormal`].
///
/// This is sometimes helpful when you have an accumulater variable where although the first
/// value of the point is normalized the subsequent values will not be so to satisfy the
/// compiler you have to set it to `NonNormal` before you start.
///
/// [`NonNormal`]: crate::marker::NonNormal
pub fn non_normal(self) -> Point<NonNormal, S, Z> {
Point::from_inner(self.0, NonNormal)
}
/// Mark the point as possibly being `Zero` (even though it isn't).
///
/// This is useful in accumulator variables where although the initial value is non-zero, every
/// sum addition after that might make it zero so it's necessary to start off with `Zero` marked
/// point.
pub fn mark_zero(self) -> Point<T, S, Zero> {
Point::from_inner(self.0, self.1)
}
}
impl<Z, T> Point<T, Public, Z> {
/// Checks if this point's x-coordiante is the equal to the scalar mod the
/// curve order. This is only useful for ECDSA implementations.
pub fn x_eq_scalar<Z2>(&self, scalar: &Scalar<Public, Z2>) -> bool {
crate::backend::VariableTime::point_x_eq_scalar(&self.0, &scalar.0)
}
}
impl<T: PointType, S, Z> core::ops::Neg for Point<T, S, Z> {
type Output = Point<T::NegationType, S, Z>;
fn neg(self) -> Self::Output {
op::point_negate(self)
}
}
impl<T: PointType, S, Z> core::ops::Neg for &Point<T, S, Z> {
type Output = Point<T::NegationType, S, Z>;
fn neg(self) -> Self::Output {
op::point_negate(self)
}
}
impl<T1, S1, Z1, T2, S2, Z2> PartialEq<Point<T2, S2, Z2>> for Point<T1, S1, Z1>
where
T1: PointType,
T2: PointType,
{
fn eq(&self, rhs: &Point<T2, S2, Z2>) -> bool {
op::point_eq(self, rhs)
}
}
impl<T: PointType, S, Z> Eq for Point<T, S, Z> {}
impl core::hash::Hash for Point<Normal, Public, NonZero> {
fn hash<H: core::hash::Hasher>(&self, state: &mut H) {
self.to_bytes().hash(state)
}
}
impl core::hash::Hash for Point<EvenY, Public, NonZero> {
fn hash<H: core::hash::Hasher>(&self, state: &mut H) {
self.to_xonly_bytes().hash(state)
}
}
impl<T1: Normalized, Z1, T2: Normalized, Z2> PartialOrd<Point<T2, Public, Z2>>
for Point<T1, Public, Z1>
{
fn partial_cmp(&self, other: &Point<T2, Public, Z2>) -> Option<core::cmp::Ordering> {
Some(self.to_bytes().cmp(&other.to_bytes()))
}
}
impl<T1: Normalized, Z1> Ord for Point<T1, Public, Z1> {
fn cmp(&self, other: &Point<T1, Public, Z1>) -> core::cmp::Ordering {
self.to_bytes().cmp(&other.to_bytes())
}
}
impl<S, Z, T: Normalized> Point<T, S, Z> {
/// Converts the point to its compressed encoding as specified by [_Standards for Efficient Cryptography_].
///
/// # Example
/// Round trip serialization with [`from_bytes`]
/// ```
/// use secp256kfun::{marker::*, Point};
/// let point = Point::random(&mut rand::thread_rng());
/// let bytes = point.to_bytes();
/// assert!(bytes[0] == 0x02 || bytes[0] == 0x03);
/// assert_eq!(
/// Point::<_, Public, NonZero>::from_bytes(bytes).unwrap(),
/// point
/// );
/// ```
///
/// [_Standards for Efficient Cryptography_]: https://www.secg.org/sec1-v2.pdf
/// [`from_bytes`]: crate::Point::from_bytes
pub fn to_bytes(&self) -> [u8; 33] {
if self.is_zero() {
[0u8; 33]
} else {
let (x, y) = backend::BackendPoint::norm_to_coordinates(&self.0);
coords_to_bytes(x, y)
}
}
}
impl<S> Point<EvenY, S, NonZero> {
/// Creates a point with `EvenY` from 32 byte x-coordinate
pub fn from_xonly_bytes(bytes: [u8; 32]) -> Option<Self> {
backend::Point::norm_from_bytes_y_oddness(bytes, false)
.map(|point| Point::from_inner(point, EvenY))
}
}
impl<T, S> Point<T, S, Zero> {
/// Convert a point that is marked as `Zero` to `NonZero`.
///
/// If the point *was* actually zero ([`is_zero`] returns true) it returns `None`.
///
/// [`is_zero`]: Point::is_zero
pub fn non_zero(self) -> Option<Point<T, S, NonZero>> {
if self.is_zero() {
None
} else {
Some(Point::from_inner(self.0, self.1))
}
}
/// Returns the [`identity element`] of the group A.K.A. the point at infinity.
///
/// # Example
/// ```
/// use secp256kfun::{g, marker::*, s, Point, G};
/// let zero = Point::<Normal, Public, _>::zero();
/// assert!(zero.is_zero());
/// assert_eq!(g!(zero + G), *G);
/// assert_eq!(zero, g!(0 * G))
/// ```
/// [`identity_element`]: https://en.wikipedia.org/wiki/Identity_element
pub fn zero() -> Self
where
T: Default,
{
Self::from_inner(backend::Point::zero(), T::default())
}
}
impl<S, T: Normalized> Point<T, S, NonZero> {
/// Returns the x and y coordinates of the point as two 32-byte arrays containing their big endian encoding.
///
/// # Example
///
/// ```
/// # use secp256kfun::Point;
/// let point = Point::random(&mut rand::thread_rng());
/// let (x_coord, y_coord) = point.coordinates();
pub fn coordinates(&self) -> ([u8; 32], [u8; 32]) {
backend::BackendPoint::norm_to_coordinates(&self.0)
}
/// Returns whether the point has an even y-coordinate
pub fn is_y_even(&self) -> bool {
op::point_is_y_even(self)
}
/// Serializes a point with `EvenY` to its 32-byte x-coordinate
pub fn to_xonly_bytes(&self) -> [u8; 32] {
self.coordinates().0
}
/// Encodes a point as its compressed encoding as specified by [_Standards for Efficient Cryptography_].
///
/// # Example
///
/// ```
/// use secp256kfun::{marker::*, Point};
/// let point = Point::random(&mut rand::thread_rng());
/// let bytes = point.to_bytes_uncompressed();
/// assert_eq!(Point::from_bytes_uncompressed(bytes).unwrap(), point);
/// ```
/// [_Standards for Efficient Cryptography_]: https://www.secg.org/sec1-v2.pdf
pub fn to_bytes_uncompressed(&self) -> [u8; 65] {
let mut bytes = [0u8; 65];
let (x, y) = backend::BackendPoint::norm_to_coordinates(&self.0);
bytes[0] = 0x04;
bytes[1..33].copy_from_slice(x.as_ref());
bytes[33..65].copy_from_slice(y.as_ref());
bytes
}
}
impl<S, Z> HashInto for Point<Normal, S, Z> {
fn hash_into(self, hash: &mut impl digest::Digest) {
hash.update(self.to_bytes().as_ref())
}
}
impl<S> HashInto for Point<EvenY, S, NonZero> {
fn hash_into(self, hash: &mut impl digest::Digest) {
hash.update(self.to_xonly_bytes().as_ref())
}
}
impl<T: Default, S, Z> subtle::ConditionallySelectable for Point<T, S, Z>
where
Self: Copy,
{
fn conditional_select(a: &Self, b: &Self, choice: subtle::Choice) -> Self {
Point::from_inner(
backend::Point::conditional_select(&a.0, &b.0, choice),
T::default(),
)
}
}
fn coords_to_bytes(x: [u8; 32], y: [u8; 32]) -> [u8; 33] {
let mut bytes = [0u8; 33];
bytes[0] = y[31] & 0x01;
bytes[0] |= 0x02;
bytes[1..].copy_from_slice(&x[..]);
bytes
}
crate::impl_debug! {
fn to_bytes<T, S,Z>(point: &Point<T, S, Z>) -> Result<[u8;33], &str> {
let mut p = point.0;
backend::VariableTime::point_normalize(&mut p);
let p: Point<Normal, S, Z> = Point::from_inner(p, Normal);
Ok(p.to_bytes())
}
}
crate::impl_display_serialize! {
fn to_bytes<S, Z>(point: &Point<Normal, S, Z>) -> [u8;33] {
point.to_bytes()
}
}
crate::impl_display_serialize! {
fn to_bytes<S>(point: &Point<EvenY, S, NonZero>) -> [u8;32] {
point.to_xonly_bytes()
}
}
crate::impl_fromstr_deserialize! {
name => "secp256k1 x-coordinate",
fn from_bytes<S>(bytes: [u8;32]) -> Option<Point<EvenY, S, NonZero>> {
Point::from_xonly_bytes(bytes)
}
}
crate::impl_fromstr_deserialize! {
name => "secp256k1 point",
fn from_bytes<S,Z: ZeroChoice>(bytes: [u8;33]) -> Option<Point<Normal,S, Z>> {
Point::from_bytes(bytes)
}
}
impl<TR, SL, SR, ZR> AddAssign<Point<TR, SR, ZR>> for Point<NonNormal, SL, Zero> {
fn add_assign(&mut self, rhs: Point<TR, SR, ZR>) {
*self = crate::op::point_add(*self, &rhs).set_secrecy::<SL>()
}
}
impl<TR, SL, SR, ZR> AddAssign<&Point<TR, SR, ZR>> for Point<NonNormal, SL, Zero> {
fn add_assign(&mut self, rhs: &Point<TR, SR, ZR>) {
*self = crate::op::point_add(*self, rhs).set_secrecy::<SL>()
}
}
impl<TR, SL, SR, ZR> SubAssign<&Point<TR, SR, ZR>> for Point<NonNormal, SL, Zero> {
fn sub_assign(&mut self, rhs: &Point<TR, SR, ZR>) {
*self = crate::op::point_sub(*self, rhs).set_secrecy::<SL>()
}
}
impl<TR, SL, SR, ZR> SubAssign<Point<TR, SR, ZR>> for Point<NonNormal, SL, Zero> {
fn sub_assign(&mut self, rhs: Point<TR, SR, ZR>) {
*self = crate::op::point_sub(*self, &rhs).set_secrecy::<SL>()
}
}
impl<S: Secrecy> core::iter::Sum for Point<NonNormal, S, Zero> {
fn sum<I: Iterator<Item = Self>>(mut iter: I) -> Self {
let mut sum = iter.next().unwrap_or(Point::zero());
for point in iter {
sum += point;
}
sum
}
}
#[cfg(test)]
mod test {
use super::*;
use crate::{g, G};
use proptest::prelude::*;
#[cfg(target_arch = "wasm32")]
use wasm_bindgen_test::wasm_bindgen_test as test;
macro_rules! expression_eq {
([$($lhs:tt)*] == [$($rhs:tt)*]) => {{
use core::borrow::Borrow;
assert_eq!(g!($($lhs)*).borrow(),g!($($rhs)*).borrow(), stringify!($($lhs)* == $($rhs)*))
}};
([$($lhs:tt)*] != [$($rhs:tt)*]) => {{
use core::borrow::Borrow;
assert_ne!(g!($($lhs)*).borrow(),g!($($rhs)*).borrow(), stringify!($($lhs)* != $($rhs)*))
}};
}
macro_rules! operations_test {
(@binary $P:expr, $Q:expr) => {{
let p = $P;
let q = $Q;
let i = Point::<Normal, Public, _>::zero();
expression_eq!([p] == [q]);
expression_eq!([q] == [p]);
expression_eq!([1 * p] == [q]);
expression_eq!([-1 * p] == [-q]);
expression_eq!([p - q] == [i]);
expression_eq!([i + p] == [q]);
if !p.is_zero() {
expression_eq!([p] != [i]);
expression_eq!([p + p] != [p]);
}
expression_eq!([-(p + p)] == [-q + -q]);
expression_eq!([p + p] == [2 * q]);
expression_eq!([p + q] == [2 * q]);
expression_eq!([q + p] == [2 * q]);
expression_eq!([p + p + p] == [3 * q]);
expression_eq!([-p - p - p] == [-3 * q]);
expression_eq!([42 * p + 1337 * p] == [1379 * q]);
expression_eq!([42 * p - 1337 * p] == [-1295 * q]);
let add_100_times = {
let p = p.clone().mark_zero().non_normal();
let i = g!(p - p);
assert_eq!(i, Point::<NonNormal, Secret,_>::zero());
(0..100).fold(i, |acc, _| g!(acc + p))
};
expression_eq!([add_100_times] == [100 * q]);
let undo = { (0..100).fold(add_100_times.clone(), |acc, _| g!(acc - p)) };
expression_eq!([undo] == [add_100_times - 100 * q]);
expression_eq!([undo] == [i]);
}};
($P:expr) => {{
let p = $P;
let i = Point::<Normal, Public, _>::zero();
expression_eq!([p] == [p]);
expression_eq!([p + i] == [p]);
expression_eq!([i - p] == [-p]);
expression_eq!([p - i] == [p]);
expression_eq!([0 * p] == [i]);
let q = p.clone().normalize().public();
operations_test!(@binary p,q);
let q = p.clone().non_normal().public();
operations_test!(@binary p,q);
let q = p.clone().normalize().secret();
operations_test!(@binary p,q);
let q = p.clone().non_normal().secret();
operations_test!(@binary p,q);
}}
}
proptest! {
#[test]
fn operations_even_y(P in any::<Point<EvenY>>()) {
operations_test!(&P);
}
#[test]
fn operations_normal(P in any::<Point<Normal>>()) {
operations_test!(&P);
}
#[test]
fn operations_jacobian(P in any::<Point<NonNormal>>()) {
operations_test!(&P);
}
#[test]
fn operations_normal_secret(P in any::<Point<Normal, Secret>>()) {
operations_test!(&P);
}
#[test]
fn operations_jacobian_secret(P in any::<Point<NonNormal, Secret>>()) {
operations_test!(&P);
}
#[test]
fn operations_normal_public_zero(P in any::<Point<Normal, Public, Zero>>()) {
operations_test!(&P);
}
#[test]
fn operations_normal_secret_zero(P in any::<Point<Normal, Secret, Zero>>()) {
operations_test!(&P);
}
#[test]
fn operations_jacobian_public_zero(P in any::<Point<NonNormal, Public, Zero>>()) {
operations_test!(&P);
}
#[test]
fn operations_jacobian_secret_zero(P in any::<Point<NonNormal, Secret, Zero>>()) {
operations_test!(&P);
}
#[cfg(feature = "serde")]
#[test]
fn point_even_y_json_deserialization_roundtrip(point in any::<Point<Normal, Public, Zero>>()) {
let string = serde_json::to_string(&point).unwrap();
let deser_point: Point<Normal, Public, Zero> = serde_json::from_str(&string).unwrap();
assert_eq!(point, deser_point);
}
}
#[test]
fn g_to_and_from_bytes() {
use core::str::FromStr;
assert_eq!(
(*G).normalize().to_bytes_uncompressed(),
crate::hex::decode_array("0479BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798483ADA7726A3C4655DA4FBFC0E1108A8FD17B448A68554199C47D08FFB10D4B8").unwrap(),
"G.to_bytes_uncompressed()"
);
assert_eq!(
Point::from_bytes_uncompressed((*G).normalize().to_bytes_uncompressed()).unwrap(),
*G
);
assert_eq!(
(*G).normalize().to_bytes(),
crate::hex::decode_array(
"0279BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798"
)
.unwrap(),
"G.to_bytes()"
);
assert_eq!(
&Point::<_, Public>::from_bytes(
crate::hex::decode_array(
"0279BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798"
)
.unwrap()
)
.unwrap(),
G
);
assert_eq!(
&Point::<_, Public>::from_bytes(
crate::hex::decode_array(
"0279BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798"
)
.unwrap()
)
.unwrap(),
&Point::<Normal, Secret>::from_str(
"0279BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798"
)
.unwrap(),
);
let neg_g = -G;
assert_eq!(
neg_g.to_bytes_uncompressed(),
// raku -e 'say (-0x483ADA7726A3C4655DA4FBFC0E1108A8FD17B448A68554199C47D08FFB10D4B8 mod 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFC2F).base(16).comb().batch(8).map(*.join).join(" ")'
crate::hex::decode_array(
"0479BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798B7C52588D95C3B9AA25B0403F1EEF75702E84BB7597AABE663B82F6F04EF2777"
).unwrap(),
"-G.to_bytes_uncompressed()"
);
assert_eq!(
neg_g.to_bytes(),
crate::hex::decode_array(
"0379BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798"
)
.unwrap(),
"-G.to_bytes()"
);
}
#[test]
fn zero_to_and_from_bytes() {
let zero = Point::<_, Public, _>::zero();
assert_eq!(Point::<_, _, Zero>::from_bytes(zero.to_bytes()), Some(zero));
}
#[test]
fn zero_cases() {
use crate::s;
let i = Point::<Normal, Public, _>::zero();
let forty_two = s!(42);
let forty_two_pub = s!(42).public();
assert!(i.is_zero());
assert!((-i).is_zero());
expression_eq!([i] == [i]);
expression_eq!([i] == [-i]);
expression_eq!([i + i] == [i]);
expression_eq!([i - i] == [i]);
// see: https://github.com/LLFourn/secp256kfun/issues/13
expression_eq!([forty_two * i] == [i]);
expression_eq!([forty_two_pub * i] == [i]);
expression_eq!([forty_two * G + forty_two * i] == [forty_two * G]);
expression_eq!([forty_two_pub * G + forty_two_pub * i] == [forty_two_pub * G]);
}
#[cfg(feature = "alloc")]
#[test]
fn fmt_debug() {
let random_point = Point::random(&mut rand::thread_rng());
assert!(format!("{random_point:?}").starts_with("Point<Normal,Public,NonZero>"));
let mult_point = g!({ Scalar::random(&mut rand::thread_rng()) } * G);
assert!(format!("{mult_point:?}").starts_with("Point<NonNormal,Public,NonZero>"));
}
#[test]
fn assign_tests() {
let a_orig = Point::random(&mut rand::thread_rng())
.mark_zero()
.non_normal();
let mut a = a_orig;
let b = Point::random(&mut rand::thread_rng());
a += b;
assert_eq!(a, op::point_add(a_orig, b));
a -= b;
assert_eq!(a, a_orig);
}
}