// SPDX-License-Identifier: MPL-2.0
//! Test vectors of serialized Prio inputs, enabling backward compatibility testing.
use crate::{field::FieldPrio2, vdaf::prio2::client::ClientError};
use serde::{Deserialize, Serialize};
use std::fmt::Debug;
/// Errors propagated by functions in this module.
#[derive(Debug, thiserror::Error)]
pub(crate) enum TestVectorError {
/// Error from Prio client
#[error("Prio client error {0}")]
Client(#[from] ClientError),
}
/// A test vector of serialized Priov2 inputs, along with a reference sum. The field is always
/// [`FieldPrio2`].
#[derive(Debug, Eq, PartialEq, Serialize, Deserialize)]
pub(crate) struct Priov2TestVector {
/// Dimension (number of buckets) of the inputs
pub dimension: usize,
/// Decrypted shares of Priov2 format inputs for the "first" a.k.a. "PHA"
/// server. The inner `Vec`s are encrypted bytes.
#[serde(
serialize_with = "base64::serialize_bytes",
deserialize_with = "base64::deserialize_bytes"
)]
pub server_1_decrypted_shares: Vec<Vec<u8>>,
/// Decrypted share of Priov2 format inputs for the non-"first" a.k.a.
/// "facilitator" server.
#[serde(
serialize_with = "base64::serialize_bytes",
deserialize_with = "base64::deserialize_bytes"
)]
pub server_2_decrypted_shares: Vec<Vec<u8>>,
/// The sum over the inputs.
#[serde(
serialize_with = "base64::serialize_field",
deserialize_with = "base64::deserialize_field"
)]
pub reference_sum: Vec<FieldPrio2>,
}
mod base64 {
//! Custom serialization module used for some members of struct
//! `Priov2TestVector` so that byte slices are serialized as base64 strings
//! instead of an array of an array of integers when serializing to JSON.
//
// Thank you, Alice!
https://users.rust-lang.org/t/serialize-a-vec-u8-to-json-as-base64/57781/2
use crate::{
codec::ParameterizedDecode,
field::{encode_fieldvec, FieldElement, FieldPrio2},
vdaf::{Share, ShareDecodingParameter},
};
use assert_matches::assert_matches;
use base64::{engine::Engine, prelude::BASE64_STANDARD};
use serde::{
de::Error as _, ser::Error as _, Deserialize, Deserializer, Serialize, Serializer,
};
pub fn serialize_bytes<S: Serializer>(v: &[Vec<u8>], s: S) -> Result<S::Ok, S::Error> {
let base64_vec = v
.iter()
.map(|bytes| BASE64_STANDARD.encode(bytes))
.collect();
<Vec<String>>::serialize(&base64_vec, s)
}
pub fn deserialize_bytes<'de, D: Deserializer<'de>>(d: D) -> Result<Vec<Vec<u8>>, D::Error> {
<Vec<String>>::deserialize(d)?
.iter()
.map(|s| {
BASE64_STANDARD
.decode(s.as_bytes())
.map_err(D::Error::custom)
})
.collect()
}
pub fn serialize_field<S: Serializer>(v: &[FieldPrio2], s: S) -> Result<S::Ok, S::Error> {
let mut bytes = Vec::new();
encode_fieldvec(v, &mut bytes).map_err(S::Error::custom)?;
String::serialize(&BASE64_STANDARD.encode(&bytes), s)
}
pub fn deserialize_field<'de, D: Deserializer<'de>>(d: D) -> Result<Vec<FieldPrio2>, D::Error> {
let bytes = BASE64_STANDARD
.decode(String::deserialize(d)?.as_bytes())
.map_err(D::Error::custom)?;
let decoding_parameter =
ShareDecodingParameter::<32>::Leader(bytes.len() / FieldPrio2::ENCODED_SIZE);
let share = Share::<FieldPrio2, 32>::get_decoded_with_param(&decoding_parameter, &bytes)
.map_err(D::Error::custom)?;
assert_matches!(share, Share::Leader(vec) => Ok(vec))
}
}
