From 6284afdb41a18b2094d346b5fe75553ef975d55c Mon Sep 17 00:00:00 2001
From: Dmitry Vdovin <voidxnull@gmail.com>
Date: Sun, 21 Jan 2024 02:45:52 +0400
Subject: [PATCH] Implement read/write for ProvingKey and VerifyingKey

---
 fawkes-crypto/src/backend/plonk/setup.rs | 53 ++++++++++++++++++++++--
 1 file changed, 49 insertions(+), 4 deletions(-)

diff --git a/fawkes-crypto/src/backend/plonk/setup.rs b/fawkes-crypto/src/backend/plonk/setup.rs
index c70b742..70d3311 100644
--- a/fawkes-crypto/src/backend/plonk/setup.rs
+++ b/fawkes-crypto/src/backend/plonk/setup.rs
@@ -1,6 +1,16 @@
 use super::{*, engines::Bn256};
-use halo2_curves::pairing::Engine as PairingEngine;
-use crate::backend::plonk::engines::Engine;
+use halo2_curves::{
+    CurveAffine,
+    ff::FromUniformBytes,
+    group::prime::PrimeCurveAffine,
+    pairing::Engine as PairingEngine,
+};
+use halo2_proofs::SerdeFormat;
+use crate::{
+    circuit::cs::BuildCS,
+    engines::bn256::Fr,
+    backend::plonk::engines::Engine
+};
 use halo2_proofs::plonk::{
     keygen_pk,
     keygen_vk,
@@ -12,19 +22,54 @@ use std::{
     rc::Rc,
     cell::{RefCell}
 };
-
-use crate::{circuit::cs::BuildCS, engines::bn256::Fr};
+use std::io::{Read, Write};
 
 #[derive(Clone, Debug)]
 pub struct ProvingKey<E: Engine>(
     pub HaloProvingKey<<E::BE as PairingEngine>::G1Affine>
 );
 
+impl<E: Engine> ProvingKey<E>
+where
+    <<E as Engine>::BE as PairingEngine>::G1Affine: SerdeObject,
+    <<<E as Engine>::BE as PairingEngine>::G1Affine as PrimeCurveAffine>::Scalar: SerdeObject + FromUniformBytes<64>,
+{
+    pub fn write<W: std::io::Write>(&self, writer: &mut W) -> std::io::Result<()> {
+        let mut w = brotli::CompressorWriter::new(writer, 4096, 9, 22);
+        self.0.write(&mut w, SerdeFormat::Processed)
+    }
+
+    pub fn read<R>(reader: &mut R) -> std::io::Result<Self>
+    where
+        R: std::io::Read,
+    {
+        let mut r = brotli::Decompressor::new(reader, 4096);
+        Ok(Self(HaloProvingKey::<<E::BE as PairingEngine>::G1Affine>::read::<_, HaloCS<BuildCS<E::Fr>>>(&mut r, SerdeFormat::Processed)?))
+    }
+}
+
 #[derive(Clone, Debug)]
 pub struct VerifyingKey<E: Engine>(
     pub HaloVerifyingKey<<E::BE as PairingEngine>::G1Affine>
 );
 
+impl<E: Engine> VerifyingKey<E>
+where
+    <<E as Engine>::BE as PairingEngine>::G1Affine: SerdeObject,
+    <<<E as Engine>::BE as PairingEngine>::G1Affine as PrimeCurveAffine>::Scalar: SerdeObject + FromUniformBytes<64>,
+{
+    pub fn write<W: std::io::Write>(&self, writer: &mut W) -> std::io::Result<()> {
+        self.0.write(writer, SerdeFormat::Processed)
+    }
+
+    pub fn read<R>(reader: &mut R) -> std::io::Result<Self>
+        where
+            R: std::io::Read,
+    {
+        Ok(Self(HaloVerifyingKey::<<E::BE as PairingEngine>::G1Affine>::read::<_, HaloCS<BuildCS<E::Fr>>>(reader, SerdeFormat::Processed)?))
+    }
+}
+
 pub fn setup<
     'a,
     Pub: Signal<BuildCS<Fr>>,