Add benchmarks for OPRF functions (under a bench feature)

src/lib.rs

@@ -383,7 +383,7 @@
 //! match `client_shared_secret`. Otherwise, on failure, the `finish` algorithm outputs the error `InvalidLoginError`.
 //!
 
-#![deny(missing_docs)]
+#![cfg_attr(not(feature = "bench"), deny(missing_docs))]
 #![deny(unsafe_code)]
 
 // Error types
@@ -401,7 +401,11 @@ pub mod map_to_curve;
 pub mod key_exchange;
 pub mod keypair;
 
+#[cfg(feature = "bench")]
+pub mod oprf;
+#[cfg(not(feature = "bench"))]
 mod oprf;
+
 pub mod slow_hash;
 
 #[cfg(test)]

src/oprf.rs

@@ -8,9 +8,9 @@ use generic_array::{typenum::U32, GenericArray};
 use hkdf::Hkdf;
 use rand_core::{CryptoRng, RngCore};
 
-pub(crate) struct OprfClientBytes<Grp: Group> {
-    pub(crate) alpha: Grp,
-    pub(crate) blinding_factor: Grp::Scalar,
+pub struct OprfClientBytes<Grp: Group> {
+    pub alpha: Grp,
+    pub blinding_factor: Grp::Scalar,
 }
 
 /// Computes the first step for the multiplicative blinding version of DH-OPRF. This
@@ -53,6 +53,36 @@ pub(crate) fn generate_oprf3<G: Group>(
     Ok(prk)
 }
 
+// Benchmarking shims
+#[cfg(feature = "bench")]
+#[inline]
+pub fn generate_oprf1_shim<R: RngCore + CryptoRng, G: GroupWithMapToCurve>(
+    input: &[u8],
+    pepper: Option<&[u8]>,
+    blinding_factor_rng: &mut R,
+) -> Result<OprfClientBytes<G>, InternalPakeError> {
+    generate_oprf1(input, pepper, blinding_factor_rng)
+}
+
+#[cfg(feature = "bench")]
+#[inline]
+pub fn generate_oprf2_shim<G: Group>(
+    point: G,
+    oprf_key: &G::Scalar,
+) -> Result<G, InternalPakeError> {
+    generate_oprf2(point, oprf_key)
+}
+
+#[cfg(feature = "bench")]
+#[inline]
+pub fn generate_oprf3_shim<G: Group>(
+    input: &[u8],
+    point: G,
+    blinding_factor: &G::Scalar,
+) -> Result<GenericArray<u8, U32>, InternalPakeError> {
+    generate_oprf3(input, point, blinding_factor)
+}
+
 // Tests
 // =====