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Adding i2osp error checking condition

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This commit is contained in:
Kevin Lewi
2021-07-08 19:38:30 -07:00
committed by Kevin Lewi
parent 6062bdb5cd
commit e6b5a5dcf6
9 changed files with 123 additions and 85 deletions
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src/oprf.rs
+32 -23
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@@ -4,7 +4,7 @@
// LICENSE file in the root directory of this source tree.
use crate::{
errors::InternalPakeError, group::Group, hash::Hash, map_to_curve::GroupWithMapToCurve,
errors::ProtocolError, group::Group, hash::Hash, map_to_curve::GroupWithMapToCurve,
serialization::serialize,
};
use digest::Digest;
@@ -32,10 +32,10 @@ static MODE_BASE: u8 = 0x00;
pub(crate) fn blind<R: RngCore + CryptoRng, G: GroupWithMapToCurve, H: Hash>(
input: &[u8],
blinding_factor_rng: &mut R,
) -> Result<(Token<G>, G), InternalPakeError> {
) -> Result<(Token<G>, G), ProtocolError> {
// Choose a random scalar that must be non-zero
let blind = G::random_nonzero_scalar(blinding_factor_rng);
let dst = [STR_VOPRF, &G::get_context_string(MODE_BASE)].concat();
let dst = [STR_VOPRF, &G::get_context_string(MODE_BASE)?].concat();
let mapped_point = G::map_to_curve::<H>(input, &dst)?;
let blind_token = mapped_point * &blind;
Ok((
@@ -59,7 +59,7 @@ pub(crate) fn finalize<G: GroupWithMapToCurve, H: Hash>(
input: &[u8],
blind: &G::Scalar,
evaluated_element: G,
) -> GenericArray<u8, <H as Digest>::OutputSize> {
) -> Result<GenericArray<u8, <H as Digest>::OutputSize>, ProtocolError> {
let unblinded_element = evaluated_element * &G::scalar_invert(blind);
finalize_after_unblind::<G, H>(input, unblinded_element)
}
@@ -67,15 +67,15 @@ pub(crate) fn finalize<G: GroupWithMapToCurve, H: Hash>(
fn finalize_after_unblind<G: GroupWithMapToCurve, H: Hash>(
input: &[u8],
unblinded_element: G,
) -> GenericArray<u8, <H as Digest>::OutputSize> {
let finalize_dst = [STR_VOPRF_FINALIZE, &G::get_context_string(MODE_BASE)].concat();
) -> Result<GenericArray<u8, <H as Digest>::OutputSize>, ProtocolError> {
let finalize_dst = [STR_VOPRF_FINALIZE, &G::get_context_string(MODE_BASE)?].concat();
let hash_input = [
serialize(input, 2),
serialize(&unblinded_element.to_arr().to_vec(), 2),
serialize(&finalize_dst, 2),
serialize(input, 2)?,
serialize(&unblinded_element.to_arr().to_vec(), 2)?,
serialize(&finalize_dst, 2)?,
]
.concat();
<H as Digest>::digest(&hash_input)
Ok(<H as Digest>::digest(&hash_input))
}
////////////////////////
@@ -88,7 +88,7 @@ fn finalize_after_unblind<G: GroupWithMapToCurve, H: Hash>(
pub fn blind_shim<R: RngCore + CryptoRng, G: GroupWithMapToCurve, H: Hash>(
input: &[u8],
blinding_factor_rng: &mut R,
) -> Result<(Token<G>, G), InternalPakeError> {
) -> Result<(Token<G>, G), ProtocolError> {
blind::<R, G, H>(input, blinding_factor_rng)
}
@@ -105,8 +105,8 @@ pub fn evaluate_shim<G: Group>(point: G, oprf_key: &G::Scalar) -> G {
pub fn finalize_shim<G: GroupWithMapToCurve, H: Hash>(
token: &Token<G>,
point: G,
) -> Result<GenericArray<u8, <H as Digest>::OutputSize>, InternalPakeError> {
Ok(finalize::<G, H>(&token.data, &token.blind, point))
) -> Result<GenericArray<u8, <H as Digest>::OutputSize>, ProtocolError> {
finalize::<G, H>(&token.data, &token.blind, point)
}
///////////
@@ -124,30 +124,34 @@ mod tests {
use sha2::Sha512;
fn prf(input: &[u8], oprf_key: &[u8; 32]) -> GenericArray<u8, <Sha512 as Digest>::OutputSize> {
let dst = [STR_VOPRF, &RistrettoPoint::get_context_string(MODE_BASE)].concat();
let dst = [
STR_VOPRF,
&RistrettoPoint::get_context_string(MODE_BASE).unwrap(),
]
.concat();
let point = RistrettoPoint::map_to_curve::<Sha512>(input, &dst).unwrap();
let scalar =
RistrettoPoint::from_scalar_slice(GenericArray::from_slice(&oprf_key[..])).unwrap();
let res = point * scalar;
finalize_after_unblind::<RistrettoPoint, sha2::Sha512>(&input, res)
finalize_after_unblind::<RistrettoPoint, sha2::Sha512>(&input, res).unwrap()
}
#[test]
fn oprf_retrieval() -> Result<(), InternalPakeError> {
fn oprf_retrieval() {
let input = b"hunter2";
let mut rng = OsRng;
let (token, alpha) = blind::<_, RistrettoPoint, Sha512>(&input[..], &mut rng)?;
let (token, alpha) = blind::<_, RistrettoPoint, Sha512>(&input[..], &mut rng).unwrap();
let oprf_key_bytes = arr![
u8; 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
24, 25, 26, 27, 28, 29, 30, 31, 32,
];
let oprf_key = RistrettoPoint::from_scalar_slice(&oprf_key_bytes)?;
let oprf_key = RistrettoPoint::from_scalar_slice(&oprf_key_bytes).unwrap();
let beta = evaluate::<RistrettoPoint>(alpha, &oprf_key);
let res = finalize::<RistrettoPoint, sha2::Sha512>(&token.data, &token.blind, beta);
let res =
finalize::<RistrettoPoint, sha2::Sha512>(&token.data, &token.blind, beta).unwrap();
let res2 = prf(&input[..], &oprf_key.as_bytes());
assert_eq!(res, res2);
Ok(())
}
#[test]
@@ -156,11 +160,16 @@ mod tests {
let mut input = vec![0u8; 64];
rng.fill_bytes(&mut input);
let (token, alpha) = blind::<_, RistrettoPoint, sha2::Sha512>(&input, &mut rng).unwrap();
let res = finalize::<RistrettoPoint, sha2::Sha512>(&token.data, &token.blind, alpha);
let res =
finalize::<RistrettoPoint, sha2::Sha512>(&token.data, &token.blind, alpha).unwrap();
let dst = [STR_VOPRF, &RistrettoPoint::get_context_string(MODE_BASE)].concat();
let dst = [
STR_VOPRF,
&RistrettoPoint::get_context_string(MODE_BASE).unwrap(),
]
.concat();
let point = RistrettoPoint::map_to_curve::<Sha512>(&input, &dst).unwrap();
let res2 = finalize_after_unblind::<RistrettoPoint, sha2::Sha512>(&input, point);
let res2 = finalize_after_unblind::<RistrettoPoint, sha2::Sha512>(&input, point).unwrap();
assert_eq!(res, res2);
}