Adding upstream version 0.70.1+ds1.upstream/0.70.1+ds1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 79 insertions, 0 deletions

diff --git a/vendor/elliptic-curve/src/ops.rs b/vendor/elliptic-curve/src/ops.rs
new file mode 100644
index 0000000..b7e9e3d
--- /dev/null
+++ b/vendor/elliptic-curve/src/ops.rs
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+//! Traits for arithmetic operations on elliptic curve field elements.
+
+pub use core::ops::{Add, AddAssign, Mul, Neg, Shr, ShrAssign, Sub, SubAssign};
+
+use crypto_bigint::Integer;
+use group::Group;
+
+/// Perform an inversion on a field element (i.e. base field element or scalar)
+pub trait Invert {
+    /// Field element type
+    type Output;
+
+    /// Invert a field element.
+    fn invert(&self) -> Self::Output;
+
+    /// Invert a field element in variable time.
+    ///
+    /// ⚠️ WARNING!
+    ///
+    /// This method should not be used with secret values, as its variable-time
+    /// operation can potentially leak secrets through sidechannels.
+    fn invert_vartime(&self) -> Self::Output {
+        // Fall back on constant-time implementation by default.
+        self.invert()
+    }
+}
+
+/// Linear combination.
+///
+/// This trait enables crates to provide an optimized implementation of
+/// linear combinations (e.g. Shamir's Trick), or otherwise provides a default
+/// non-optimized implementation.
+// TODO(tarcieri): replace this with a trait from the `group` crate? (see zkcrypto/group#25)
+pub trait LinearCombination: Group {
+    /// Calculates `x * k + y * l`.
+    fn lincomb(x: &Self, k: &Self::Scalar, y: &Self, l: &Self::Scalar) -> Self {
+        (*x * k) + (*y * l)
+    }
+}
+
+/// Multiplication by the generator.
+///
+/// May use optimizations (e.g. precomputed tables) when available.
+// TODO(tarcieri): replace this with `Group::mul_by_generator``? (see zkcrypto/group#44)
+pub trait MulByGenerator: Group {
+    /// Multiply by the generator of the prime-order subgroup.
+    #[must_use]
+    fn mul_by_generator(scalar: &Self::Scalar) -> Self {
+        Self::generator() * scalar
+    }
+}
+
+/// Modular reduction.
+pub trait Reduce<Uint: Integer>: Sized {
+    /// Bytes used as input to [`Reduce::reduce_bytes`].
+    type Bytes: AsRef<[u8]>;
+
+    /// Perform a modular reduction, returning a field element.
+    fn reduce(n: Uint) -> Self;
+
+    /// Interpret the given bytes as an integer and perform a modular reduction.
+    fn reduce_bytes(bytes: &Self::Bytes) -> Self;
+}
+
+/// Modular reduction to a non-zero output.
+///
+/// This trait is primarily intended for use by curve implementations such
+/// as the `k256` and `p256` crates.
+///
+/// End users should use the [`Reduce`] impl on
+/// [`NonZeroScalar`][`crate::NonZeroScalar`] instead.
+pub trait ReduceNonZero<Uint: Integer>: Reduce<Uint> + Sized {
+    /// Perform a modular reduction, returning a field element.
+    fn reduce_nonzero(n: Uint) -> Self;
+
+    /// Interpret the given bytes as an integer and perform a modular reduction
+    /// to a non-zero output.
+    fn reduce_nonzero_bytes(bytes: &Self::Bytes) -> Self;
+}