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diff --git a/vendor/elliptic-curve/src/ops.rs b/vendor/elliptic-curve/src/ops.rs
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+++ 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, Sub, SubAssign};
+
+use crypto_bigint::{ArrayEncoding, ByteArray, Integer};
+
+#[cfg(feature = "arithmetic")]
+use {group::Group, subtle::CtOption};
+
+#[cfg(feature = "digest")]
+use digest::FixedOutput;
+
+/// 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;
+}
+
+#[cfg(feature = "arithmetic")]
+impl<F: ff::Field> Invert for F {
+    type Output = CtOption<F>;
+
+    fn invert(&self) -> CtOption<F> {
+        ff::Field::invert(self)
+    }
+}
+
+/// 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)
+#[cfg(feature = "arithmetic")]
+#[cfg_attr(docsrs, doc(cfg(feature = "arithmetic")))]
+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)
+    }
+}
+
+/// Modular reduction.
+pub trait Reduce<UInt: Integer + ArrayEncoding>: Sized {
+    /// Perform a modular reduction, returning a field element.
+    fn from_uint_reduced(n: UInt) -> Self;
+
+    /// Interpret the given byte array as a big endian integer and perform
+    /// a modular reduction.
+    fn from_be_bytes_reduced(bytes: ByteArray<UInt>) -> Self {
+        Self::from_uint_reduced(UInt::from_be_byte_array(bytes))
+    }
+
+    /// Interpret the given byte array as a little endian integer and perform a
+    /// modular reduction.
+    fn from_le_bytes_reduced(bytes: ByteArray<UInt>) -> Self {
+        Self::from_uint_reduced(UInt::from_le_byte_array(bytes))
+    }
+
+    /// Interpret a digest as a big endian integer and perform a modular
+    /// reduction.
+    #[cfg(feature = "digest")]
+    #[cfg_attr(docsrs, doc(cfg(feature = "digest")))]
+    fn from_be_digest_reduced<D>(digest: D) -> Self
+    where
+        D: FixedOutput<OutputSize = UInt::ByteSize>,
+    {
+        Self::from_be_bytes_reduced(digest.finalize_fixed())
+    }
+
+    /// Interpret a digest as a little endian integer and perform a modular
+    /// reduction.
+    #[cfg(feature = "digest")]
+    #[cfg_attr(docsrs, doc(cfg(feature = "digest")))]
+    fn from_le_digest_reduced<D>(digest: D) -> Self
+    where
+        D: FixedOutput<OutputSize = UInt::ByteSize>,
+    {
+        Self::from_le_bytes_reduced(digest.finalize_fixed())
+    }
+}
+
+/// 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 + ArrayEncoding>: Sized {
+    /// Perform a modular reduction, returning a field element.
+    fn from_uint_reduced_nonzero(n: UInt) -> Self;
+}