shuklaayush / halo2-plonky2-verifier

Halo2 gadgets for verifying plonky2/starky proofs (WIP)

Halo2 plonky2 verifier

This repository contains halo2 gadgets to verify plonky2/starky proofs. It uses Axiom's halo2-lib under the hood.

Currently, the code can verify FRI proofs from plonky2, and full proof verification is still WIP.

TODOs:

• FRI verification
• STARK vanishing polynomial evaluation
• PLONK verification
• Benchmarking

Test

To run the mock prover for verification of a Fibonacci STARK:

cargo t -r -- --nocapture test_fibonacci_stark

Acknowledgements

This code is adapted from the original recursive verifier implementation in plonky2.

Succinct's gnark-plonky2-verifier was also used as a reference, and the PoseidonBN254 implementation is adapted from there.

Other references:

• halo2-fri-gadget: Contains gadgets for Winterfell FRI proof verification for proofs generated in a circuit's native field.
• plonky2-circom

Disclaimer

These gadgets have NOT been formally audited. Therefore, they should not be deployed in production.

halo2-plonky2-verifier's Issues

Use `QuantumCell` everywhere

Try to use QuantumCell instead of AssignedValue to prevent unnecessary assignments

Generic field extension chip

Field extension chip using const generics

Lazy reduction in GoldilocksChip

Reduction involves expensive range-checking. Limit reductions, maybe by lazily doing them implicitly only when required

Benchmarking

Add benchmarks for some real circuits, PoseidonBN254 vs PoseidonGL

Cleanup TODOs

PLONK verification

Add verifiers for plonk gates
https://github.com/0xPolygonZero/plonky2/tree/main/plonky2/src/gates

Add a FieldChip trait