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1 | 1 | //! Workaround for `ark_ff` lacking Serde support. |
2 | 2 | //! See <https://github.com/arkworks-rs/algebra/pull/506> |
3 | 3 |
|
4 | | -use ark_serialize::{CanonicalDeserialize, CanonicalSerialize}; |
5 | 4 | use serde::{de::Error as _, ser::Error as _, Deserialize as _, Deserializer, Serializer}; |
6 | 5 |
|
7 | | -pub fn serialize<T, S>(obj: &T, serializer: S) -> Result<S::Ok, S::Error> |
8 | | -where |
9 | | - T: CanonicalSerialize, |
10 | | - S: Serializer, |
11 | | -{ |
12 | | - // Convert to bytes |
13 | | - let mut buf = Vec::with_capacity(obj.compressed_size()); |
14 | | - obj.serialize_compressed(&mut buf) |
15 | | - .map_err(|e| S::Error::custom(format!("Failed to serialize: {e}")))?; |
16 | | - |
17 | | - // Write bytes |
18 | | - if serializer.is_human_readable() { |
19 | | - // ark_serialize doesn't have human-readable serialization. And Serde |
20 | | - // doesn't have good defaults for [u8]. So we manually implement hexadecimal |
21 | | - // serialization. |
22 | | - let hex = hex::encode(buf); |
23 | | - serializer.serialize_str(&hex) |
24 | | - } else { |
25 | | - serializer.serialize_bytes(&buf) |
| 6 | +/// Serialize using ark_serialize |
| 7 | +pub mod canonical { |
| 8 | + use ark_serialize::{CanonicalDeserialize, CanonicalSerialize}; |
| 9 | + |
| 10 | + use super::*; |
| 11 | + |
| 12 | + pub fn serialize<T, S>(obj: &T, serializer: S) -> Result<S::Ok, S::Error> |
| 13 | + where |
| 14 | + T: CanonicalSerialize, |
| 15 | + S: Serializer, |
| 16 | + { |
| 17 | + let mut buf = Vec::with_capacity(obj.compressed_size()); |
| 18 | + obj.serialize_compressed(&mut buf) |
| 19 | + .map_err(|e| S::Error::custom(format!("Failed to serialize: {e}")))?; |
| 20 | + super::bytes::serialize(&buf, serializer) |
| 21 | + } |
| 22 | + |
| 23 | + pub fn deserialize<'de, T, D>(deserializer: D) -> Result<T, D::Error> |
| 24 | + where |
| 25 | + T: CanonicalDeserialize, |
| 26 | + D: Deserializer<'de>, |
| 27 | + { |
| 28 | + let bytes = super::bytes::deserialize(deserializer)?; |
| 29 | + let mut reader = &*bytes; |
| 30 | + let obj = T::deserialize_compressed(&mut reader) |
| 31 | + .map_err(|e| D::Error::custom(format!("while deserializing: {e}")))?; |
| 32 | + if !reader.is_empty() { |
| 33 | + return Err(D::Error::custom("while deserializing: trailing bytes")); |
| 34 | + } |
| 35 | + |
| 36 | + Ok(obj) |
26 | 37 | } |
27 | 38 | } |
28 | 39 |
|
29 | | -pub fn deserialize<'de, T, D>(deserializer: D) -> Result<T, D::Error> |
30 | | -where |
31 | | - T: CanonicalDeserialize, |
32 | | - D: Deserializer<'de>, |
33 | | -{ |
34 | | - // Read bytes |
35 | | - let bytes = if deserializer.is_human_readable() { |
36 | | - let hex = String::deserialize(deserializer)?; |
37 | | - hex::decode(hex).map_err(|e| D::Error::custom(format!("while deserializing bytes: {e}")))? |
38 | | - } else { |
39 | | - <Vec<u8>>::deserialize(deserializer)? |
| 40 | +pub mod bytes { |
| 41 | + use super::*; |
| 42 | + |
| 43 | + pub fn serialize<S>(value: &[u8], serializer: S) -> Result<S::Ok, S::Error> |
| 44 | + where |
| 45 | + S: Serializer, |
| 46 | + { |
| 47 | + if serializer.is_human_readable() { |
| 48 | + let hex = hex::encode(value); |
| 49 | + serializer.serialize_str(&hex) |
| 50 | + } else { |
| 51 | + serializer.serialize_bytes(value) |
| 52 | + } |
| 53 | + } |
| 54 | + |
| 55 | + pub fn deserialize<'de, D>(deserializer: D) -> Result<Vec<u8>, D::Error> |
| 56 | + where |
| 57 | + D: Deserializer<'de>, |
| 58 | + { |
| 59 | + if deserializer.is_human_readable() { |
| 60 | + let hex = String::deserialize(deserializer)?; |
| 61 | + hex::decode(hex) |
| 62 | + .map_err(|e| D::Error::custom(format!("while deserializing bytes: {e}"))) |
| 63 | + } else { |
| 64 | + <Vec<u8>>::deserialize(deserializer) |
| 65 | + } |
| 66 | + } |
| 67 | +} |
| 68 | + |
| 69 | +pub mod bigint { |
| 70 | + use std::iter::repeat; |
| 71 | + |
| 72 | + use ark_ff::BigInteger; |
| 73 | + use zerocopy::IntoBytes; |
| 74 | + |
| 75 | + use super::*; |
| 76 | + |
| 77 | + pub fn serialize<T, S>(obj: &T, serializer: S) -> Result<S::Ok, S::Error> |
| 78 | + where |
| 79 | + T: BigInteger, |
| 80 | + S: Serializer, |
| 81 | + { |
| 82 | + // Encode as big endian bytes without leading zeros. |
| 83 | + let value = obj.to_bytes_be(); |
| 84 | + let leading_zeros = value.iter().take_while(|&&b| b == 0).count(); |
| 85 | + let value = &value[leading_zeros..]; |
| 86 | + bytes::serialize(value, serializer) |
| 87 | + } |
| 88 | + |
| 89 | + pub fn deserialize<'de, T, D>(deserializer: D) -> Result<T, D::Error> |
| 90 | + where |
| 91 | + T: BigInteger, |
| 92 | + D: Deserializer<'de>, |
| 93 | + { |
| 94 | + let bytes = super::bytes::deserialize(deserializer)?; |
| 95 | + if bytes[0] == 0 { |
| 96 | + return Err(D::Error::custom("Bigint has leading zeros.")); |
| 97 | + } |
| 98 | + if bytes.len() > T::NUM_LIMBS * 8 { |
| 99 | + return Err(D::Error::custom("Value exceeds target size.")); |
| 100 | + } |
| 101 | + let le_bytes = bytes.into_iter().rev().chain(repeat(0_u8)); |
| 102 | + |
| 103 | + let mut result = T::default(); |
| 104 | + #[cfg(target_endian = "little")] |
| 105 | + let bytes = result.as_mut().as_mut_bytes(); |
| 106 | + for (dst, src) in bytes.iter_mut().zip(le_bytes) { |
| 107 | + *dst = src; |
| 108 | + } |
| 109 | + Ok(result) |
| 110 | + } |
| 111 | +} |
| 112 | + |
| 113 | +pub mod field { |
| 114 | + use ark_ff::{Field, PrimeField}; |
| 115 | + use serde::{ser::SerializeSeq, Deserialize, Serialize}; |
| 116 | + |
| 117 | + use super::*; |
| 118 | + |
| 119 | + struct Wrapper<F: Field>(F); |
| 120 | + |
| 121 | + impl<F: Field> Serialize for Wrapper<F> { |
| 122 | + fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error> |
| 123 | + where |
| 124 | + S: Serializer, |
| 125 | + { |
| 126 | + serialize(&self.0, serializer) |
| 127 | + } |
| 128 | + } |
| 129 | + |
| 130 | + impl<'de, F: Field> Deserialize<'de> for Wrapper<F> { |
| 131 | + fn deserialize<D>(deserializer: D) -> Result<Self, D::Error> |
| 132 | + where |
| 133 | + D: Deserializer<'de>, |
| 134 | + { |
| 135 | + deserialize(deserializer).map(Wrapper) |
| 136 | + } |
| 137 | + } |
| 138 | + |
| 139 | + pub fn serialize<T, S>(obj: &T, serializer: S) -> Result<S::Ok, S::Error> |
| 140 | + where |
| 141 | + T: Field, |
| 142 | + S: Serializer, |
| 143 | + { |
| 144 | + if T::extension_degree() == 1 { |
| 145 | + // For prime fields encode the element directly |
| 146 | + let base = obj.to_base_prime_field_elements().next().unwrap(); |
| 147 | + super::bigint::serialize(&base.into_bigint(), serializer) |
| 148 | + } else { |
| 149 | + // For extension fields encode a sequence of base field elements. |
| 150 | + let mut seq = serializer.serialize_seq(Some(T::extension_degree() as usize))?; |
| 151 | + for coeff in obj.to_base_prime_field_elements() { |
| 152 | + seq.serialize_element(&Wrapper(coeff))?; |
| 153 | + } |
| 154 | + seq.end() |
| 155 | + } |
| 156 | + } |
| 157 | + |
| 158 | + pub fn deserialize<'de, T, D>(deserializer: D) -> Result<T, D::Error> |
| 159 | + where |
| 160 | + T: Field, |
| 161 | + D: Deserializer<'de>, |
| 162 | + { |
| 163 | + if T::extension_degree() == 1 { |
| 164 | + let bigint = super::bigint::deserialize(deserializer)?; |
| 165 | + let base = T::BasePrimeField::from_bigint(bigint) |
| 166 | + .ok_or_else(|| D::Error::custom("Prime field element not reduced."))?; |
| 167 | + Ok(T::from_base_prime_field(base)) |
| 168 | + } else { |
| 169 | + let coeffs = <Vec<Wrapper<T::BasePrimeField>>>::deserialize(deserializer)?; |
| 170 | + let num_coeffs = coeffs.len(); |
| 171 | + let coeffs = coeffs.into_iter().map(|c| c.0); |
| 172 | + T::from_base_prime_field_elems(coeffs).ok_or_else(|| { |
| 173 | + D::Error::custom(format!( |
| 174 | + "Incorrect number of elements {num_coeffs} for extension degree {}", |
| 175 | + T::extension_degree() |
| 176 | + )) |
| 177 | + }) |
| 178 | + } |
| 179 | + } |
| 180 | +} |
| 181 | + |
| 182 | +#[cfg(test)] |
| 183 | +mod tests { |
| 184 | + use ark_ff::{BigInteger, Field, PrimeField, UniformRand}; |
| 185 | + use serde::{Deserialize, Serialize}; |
| 186 | + |
| 187 | + use crate::{ |
| 188 | + crypto::fields::{Field256, Field64, Field64_3}, |
| 189 | + utils::test_serde, |
40 | 190 | }; |
41 | 191 |
|
42 | | - // Convert to object |
43 | | - let mut reader = &*bytes; |
44 | | - let obj = T::deserialize_compressed(&mut reader) |
45 | | - .map_err(|e| D::Error::custom(format!("while deserializing: {e}")))?; |
46 | | - if !reader.is_empty() { |
47 | | - return Err(D::Error::custom("while deserializing: trailing bytes")); |
| 192 | + #[test] |
| 193 | + fn test_bigint() { |
| 194 | + #[derive(Serialize, Deserialize, Debug, PartialEq, Eq)] |
| 195 | + struct Wrapper<T: BigInteger>(#[serde(with = "crate::ark_serde::bigint")] T); |
| 196 | + |
| 197 | + test_serde(&Wrapper(Field256::MODULUS)); |
| 198 | + test_serde(&Wrapper(Field64::MODULUS)); |
48 | 199 | } |
49 | 200 |
|
50 | | - Ok(obj) |
| 201 | + #[test] |
| 202 | + fn test_field() { |
| 203 | + #[derive(Serialize, Deserialize, Debug, PartialEq, Eq)] |
| 204 | + struct Wrapper<T: Field>(#[serde(with = "crate::ark_serde::field")] T); |
| 205 | + |
| 206 | + let mut rng = ark_std::rand::thread_rng(); |
| 207 | + |
| 208 | + test_serde(&Wrapper(Field256::rand(&mut rng))); |
| 209 | + test_serde(&Wrapper(Field64::rand(&mut rng))); |
| 210 | + test_serde(&Wrapper(Field64_3::rand(&mut rng))); |
| 211 | + } |
51 | 212 | } |
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