367 lines
14 KiB
Rust

use std::marker::PhantomData;
use plonky2::hash::hash_types::RichField;
use plonky2::iop::target::{BoolTarget, Target};
use plonky2::iop::witness::{PartialWitness, WitnessWrite};
use plonky2::plonk::circuit_builder::CircuitBuilder;
use plonky2::plonk::circuit_data::{VerifierCircuitData, VerifierCircuitTarget, VerifierOnlyCircuitData};
use plonky2::plonk::config::{AlgebraicHasher, GenericConfig};
use plonky2::plonk::proof::{ProofWithPublicInputs, ProofWithPublicInputsTarget};
use plonky2_field::extension::Extendable;
use plonky2_poseidon2::poseidon2_hash::poseidon2::Poseidon2;
use crate::{error::CircuitError,Result};
use crate::circuit_helper::Plonky2Circuit;
use crate::recursion::dummy_gen::DummyProofGen;
use crate::recursion::utils::bucket_count;
/// recursion node circuit
/// N: number of leaf proofs
/// T: total number of sampling proofs
#[derive(Clone, Debug)]
pub struct NodeCircuit<
F: RichField + Extendable<D> + Poseidon2,
const D: usize,
C: GenericConfig<D, F = F>,
H: AlgebraicHasher<F>,
const N: usize,
const T: usize,
> where
<C as GenericConfig<D>>::Hasher: AlgebraicHasher<F>
{
leaf_verifier_data: VerifierCircuitData<F, C, D>,
phantom_data: PhantomData<H>
}
/// recursion node targets
/// leaf_proofs: leaf proofs
/// node_verifier_data: node verifier data, note: leaf verifier data is constant
/// condition: for switching between leaf and node verifier data
/// index: index of the node
/// flags: boolean target for each flag/signal for switching between real and dummy leaf proof
#[derive(Clone, Debug)]
pub struct NodeTargets<
const D: usize,
>{
pub inner_proofs: Vec<ProofWithPublicInputsTarget<D>>,
pub inner_verifier_data: VerifierCircuitTarget,
pub condition: BoolTarget,
pub index: Target,
pub flags: Vec<BoolTarget>,
}
#[derive(Clone, Debug)]
pub struct NodeInput<
F: RichField + Extendable<D> + Poseidon2,
const D: usize,
C: GenericConfig<D, F = F>,
>{
pub inner_proofs: Vec<ProofWithPublicInputs<F, C, D>>,
pub verifier_only_data: VerifierOnlyCircuitData<C, D>,
pub condition: bool,
pub flags: Vec<bool>,
pub index: usize
}
impl<
F: RichField + Extendable<D> + Poseidon2,
const D: usize,
C: GenericConfig<D, F = F>,
H: AlgebraicHasher<F>,
const N: usize,
const T: usize,
> NodeCircuit<F,D,C,H, N,T> where
<C as GenericConfig<D>>::Hasher: AlgebraicHasher<F>
{
pub fn new(
leaf_verifier_data: VerifierCircuitData<F, C, D>,
) -> Self {
assert!(N.is_power_of_two(), "M is NOT a power of two");
Self{
leaf_verifier_data,
phantom_data:PhantomData::default(),
}
}
}
impl<
F: RichField + Extendable<D> + Poseidon2,
const D: usize,
C: GenericConfig<D, F = F>,
H: AlgebraicHasher<F>,
const N: usize,
const T: usize,
> Plonky2Circuit<F, C, D> for NodeCircuit<F, D, C, H, N, T> where
<C as GenericConfig<D>>::Hasher: AlgebraicHasher<F>
{
type Targets = NodeTargets<D>;
type Input = NodeInput<F, D, C>;
fn add_targets(&self, builder: &mut CircuitBuilder<F, D>, register_pi: bool) -> Result<Self::Targets> {
let inner_common = self.leaf_verifier_data.common.clone();
let zero_target = builder.zero();
// assert public input is of size 8 + 1 (index) + B (flag buckets)
let n_bucket: usize = bucket_count(T);
assert_eq!(inner_common.num_public_inputs, 9+n_bucket);
// the proof virtual targets - M proofs
let mut vir_proofs = vec![];
let mut pub_input = vec![];
let mut inner_flag_buckets = vec![];
let mut inner_indexes = vec![];
for _i in 0..N {
let vir_proof = builder.add_virtual_proof_with_pis(&inner_common);
let inner_pub_input = vir_proof.public_inputs.clone();
vir_proofs.push(vir_proof);
pub_input.extend_from_slice(&inner_pub_input[0..4]);
inner_indexes.push(inner_pub_input[8]);
inner_flag_buckets.push(inner_pub_input[9..(9+n_bucket)].to_vec());
}
// hash the public input & make it public
let hash_inner_pub_input = builder.hash_n_to_hash_no_pad::<H>(pub_input);
if register_pi{
builder.register_public_inputs(&hash_inner_pub_input.elements);
}
// virtual target for the verifier data
let node_verifier_data = builder.add_virtual_verifier_data(inner_common.config.fri_config.cap_height);
// virtual target for the verifier data
let const_leaf_verifier_data = builder.constant_verifier_data(&self.leaf_verifier_data.verifier_only);
// virtual constant target for dummy verifier data
let const_dummy_vd = builder.constant_verifier_data(
&DummyProofGen::<F,D,C>::gen_dummy_verifier_data(&inner_common)
);
// register only the node verifier data hash as public input.
let mut vd_pub_input = vec![];
vd_pub_input.extend_from_slice(&node_verifier_data.circuit_digest.elements);
for i in 0..builder.config.fri_config.num_cap_elements() {
vd_pub_input.extend_from_slice(&node_verifier_data.constants_sigmas_cap.0[i].elements);
}
let vd_hash = builder.hash_n_to_hash_no_pad::<H>(vd_pub_input);
if register_pi {
builder.register_public_inputs(&vd_hash.elements);
}
// condition for switching between node and leaf
let condition = builder.add_virtual_bool_target_safe();
// flag buckets targets
let mut flag_buckets: Vec<Target> = (0..n_bucket).map(|_i| zero_target.clone()).collect();
// index: 0 <= index < T where T = total number of proofs
let index = builder.add_virtual_public_input();
let flags: Vec<BoolTarget> = (0..N).map(|_i| builder.add_virtual_bool_target_safe()).collect();
// condition: true -> node, false -> leaf
let node_or_leaf_vd = builder.select_verifier_data(condition.clone(), &node_verifier_data, &const_leaf_verifier_data);
// verify the proofs in-circuit - M proofs
for i in 0..N {
// flag: true -> real, false -> dummy
let selected_vd = builder.select_verifier_data(flags[i].clone(), &node_or_leaf_vd, &const_dummy_vd);
builder.verify_proof::<C>(&vir_proofs[i], &selected_vd, &inner_common);
}
// Check flag buckets for dummy inner proofs:
// For each inner proof, if its corresponding flag `flags[i]` is false,
// then enforce that every bucket in inner_flag_buckets[i] is zero.
for i in 0..N {
let not_flag_i = builder.not(flags[i]);
let not_flag_val = not_flag_i.target;
for j in 0..n_bucket {
// Enforce: inner_flag_buckets[i][j] * (not_flag_val) = 0.
// If flag is false then not_flag_val = 1, forcing inner_flag_buckets[i][j] to be zero
let product = builder.mul(inner_flag_buckets[i][j], not_flag_val);
builder.connect(product, zero_target.clone());
}
}
// check inner proof indexes are correct
let m_const = builder.constant(F::from_canonical_u64(N as u64));
let mut expected_inner_index = builder.mul(index, m_const);
for i in 0..N {
if i > 0 {
let i_const = builder.constant(F::from_canonical_u64(i as u64));
expected_inner_index = builder.add(expected_inner_index, i_const);
}
builder.connect(expected_inner_index, inner_indexes[i]);
}
// add flag buckets
for i in 0..flag_buckets.len(){
for j in 0..inner_flag_buckets.len() {
flag_buckets[i] = builder.add(flag_buckets[i], inner_flag_buckets[j][i]);
}
}
// make flag buckets public
builder.register_public_inputs(&flag_buckets);
// Make sure we have every gate
for g in &inner_common.gates {
builder.add_gate_to_gate_set(g.clone());
}
// return targets
let t = NodeTargets {
inner_proofs: vir_proofs,
inner_verifier_data: node_verifier_data,
condition,
index,
flags,
};
Ok(t)
}
fn assign_targets(&self, pw: &mut PartialWitness<F>, targets: &Self::Targets, input: &Self::Input) -> Result<()> {
// assert size of proofs vec
assert_eq!(input.inner_proofs.len(), N);
assert_eq!(input.flags.len(), N);
assert!(input.index <= T, "given index is not valid");
// assign the proofs
for i in 0..N {
pw.set_proof_with_pis_target(&targets.inner_proofs[i], &input.inner_proofs[i])
.map_err(|e| {
CircuitError::ProofTargetAssignmentError("inner-proof".to_string(), e.to_string())
})?;
}
// assign the verifier data
pw.set_verifier_data_target(&targets.inner_verifier_data, &input.verifier_only_data)
.map_err(|e| {
CircuitError::VerifierDataTargetAssignmentError(e.to_string())
})?;
// assign the condition - for switching between leaf & node
pw.set_bool_target(targets.condition, input.condition)
.map_err(|e| CircuitError::BoolTargetAssignmentError("condition".to_string(), e.to_string()))?;
// Assign the global index.
pw.set_target(targets.index, F::from_canonical_u64(input.index as u64))
.map_err(|e| CircuitError::TargetAssignmentError(format!("index {}", input.index),e.to_string()))?;
// Assign the flags - switch between real & fake proof
for i in 0..N {
pw.set_bool_target(targets.flags[i], input.flags[i])
.map_err(|e| CircuitError::TargetAssignmentError(format!("flag {}", input.flags[i]), e.to_string()))?;
}
Ok(())
}
}
#[cfg(test)]
mod tests {
use super::*;
use plonky2::plonk::config::PoseidonGoldilocksConfig;
use plonky2::plonk::circuit_builder::CircuitBuilder;
use plonky2::plonk::config::GenericConfig;
use plonky2_field::types::{Field, PrimeField64};
use plonky2::plonk::circuit_data::{CircuitConfig, CircuitData};
use plonky2_poseidon2::poseidon2_hash::poseidon2::{Poseidon2, Poseidon2Hash};
use crate::recursion::leaf::BUCKET_SIZE;
// For our tests, we define:
const D: usize = 2;
type C = PoseidonGoldilocksConfig;
type F = <C as GenericConfig<D>>::F;
type H = Poseidon2Hash;
/// A helper to build a minimal leaf circuit (with 9+B public inputs)
/// and return the circuit data and targets
fn dummy_leaf<const B: usize>() -> (CircuitData<F, C, D>, Vec<Target>) {
let config = CircuitConfig::standard_recursion_config();
let mut builder = CircuitBuilder::<F, D>::new(config);
let mut pub_input = vec![];
for i in 0..9+B {
pub_input.push(builder.add_virtual_public_input());
}
let data = builder.build::<C>();
(data, pub_input)
}
/// A helper to generate test leaf proofs with given data, targets, and indices.
fn dummy_leaf_proofs<const B: usize>(data: CircuitData<F, C, D>, pub_input: Vec<Target>, indices: Vec<usize>) -> Vec<ProofWithPublicInputs<F, C, D>> {
let mut proofs = vec![];
for k in 0..indices.len() {
let mut pw = PartialWitness::new();
for i in 0..8 {
pw.set_target(pub_input[i], F::ZERO).expect("assign error");
}
pw.set_target(pub_input[8], F::from_canonical_u64(indices[k] as u64)).expect("assign error");
let f_buckets = fill_buckets(indices[k], BUCKET_SIZE, B);
for i in 0..f_buckets.len() {
pw.set_target(pub_input[9 + i], f_buckets[i]).expect("assign error");
}
// Run all the generators. (This method is typically called in the proving process.)
proofs.push(data.prove(pw).expect("prove failed"));
}
proofs
}
/// helper: returns the flag buckets with the single bit at given `index` set to true `1`
fn fill_buckets(index: usize, bucket_size: usize, num_buckets: usize) -> Vec<F>{
assert!(index < bucket_size * num_buckets, "Index out of range");
let q = index / bucket_size; // bucket index
let r = index % bucket_size; // bucket bit
let mut buckets = vec![F::ZERO; num_buckets];
// Set the selected bucket to 2^r.
buckets[q] = F::from_canonical_u64(1 << r);
buckets
}
/// End-to-End test for the entire node circuit.
#[test]
fn test_full_node_circuit() -> anyhow::Result<()> {
const N: usize = 2;
const B: usize = 4; // bucket size
const T: usize = 128;
let (leaf_data, leaf_pi) = dummy_leaf::<B>();
let leaf_vd = leaf_data.verifier_data();
let indices = vec![0,1];
let leaf_proofs = dummy_leaf_proofs::<B>(leaf_data,leaf_pi,indices);
let node = NodeCircuit::<F, D, C, H, N, T>::new(leaf_vd.clone());
// Build the node circuit.
let (targets, circuit_data) = node.build_with_standard_config()?;
let verifier_data = circuit_data.verifier_data();
let prover_data = circuit_data.prover_data();
// node input
let input = NodeInput {
inner_proofs: leaf_proofs,
verifier_only_data: leaf_vd.verifier_only.clone(),
condition: false,
flags: vec![true, true],
index: 0,
};
let proof = node.prove(&targets, &input, &prover_data)?;
// Verify the proof.
assert!(verifier_data.verify(proof.clone()).is_ok(), "Proof verification failed");
println!("Public inputs: {:?}", proof.public_inputs);
// the flag buckets appeared at positions 8..12.
let flag_buckets: Vec<u64> = proof.public_inputs[9..(9+B)]
.iter()
.map(|f| f.to_canonical_u64())
.collect();
// With index = 45, we expect bucket 1 = 2^13 = 8192, and the rest 0.
let expected = vec![3, 0, 0, 0];
assert_eq!(flag_buckets, expected, "Flag bucket values mismatch");
Ok(())
}
}