ckb-bf-zkvm

A BrainFuck zkVM implementation on CKB, using Halo2.

Features

• Use Halo2(modified version from scroll)
• Use bn254 as pairing
• Use KZG
• Verifier on CKB(RISC-V)
• Implement BrainFuck instructions

Performance and Highlights

• Proof size: ~4K bytes, constant
• Cycles: ~130M, constant
• Verifier parameters: 516 bytes, always fixed
• Verifying key size: ~2K bytes, fixed if the circuit is fixed

The verifier parameters can be hard-coded. A new verifying key is needed only for every new circuit.

How to Build

Install tool (Do it only once):

make install

Build verifier and prover:

make all

Run script on ckb-debugger:

make run-tx

Crates

• ckb_bf_base: shared code between prover and verifier.
• ckb_bf_prover: prover. This is the only crate for std only. Run on native machine.
• ckb_bf_verifier: verifier. Run on CKB in RISC-V
• ckb_bf_vm: Virtual Machine.
• halo2, halo2_gadgets, halo2_proofs, poseidon: halo2 crates.