Python implementation of zk-SNARKs (Zero Knowledge Succint Non-interactive ARgument of Knowledge) using simple Symbolic expression.
Warning
This library is intended to be used as proof of concept, prototyping, and educational purpose only. It is still in active development and not fully tested!
zksnake currently only support Groth16 proving scheme with BN254 and BLS12-381 as supported curves. More proving schemes will be implemented in the future (hopefully).
from zksnake.symbolic import Symbol
from zksnake.r1cs import ConstraintSystem
x = Symbol('x')
y = Symbol('y')
v1 = Symbol('v1')
# prove the solution of y == x**3 + x + 5
# where x as input and y as output
cs = ConstraintSystem(['x'], ['y'])
cs.add_constraint(v1 == x*x)
cs.add_constraint(y - 5 - x == v1*x)
cs.set_public(y)
qap = cs.compile()Alternatively, you can import the constraints from Circom:
from zksnake.r1cs import ConstraintSystem
cs = ConstraintSystem.from_file("circuit.r1cs", "circuit.sym")
qap = cs.compile()Note that some constraints that are complex or expensive (require off-circuit computation) cannot be imported directly and require you to add "hint" function to pre-define the variable value (see Example).
from zksnake.groth16 import Setup
# one time setup
setup = Setup(qap)
prover_key, verifier_key = setup.generate()from zksnake.groth16 import Prover, Verifier
# solve the constraint system
public_witness, private_witness = cs.solve({'x': 3}, {'y': 35})
# proving
prover = Prover(qap, prover_key)
proof = prover.prove(public_witness, private_witness)
# verification
verifier = Verifier(verifier_key)
assert verifier.verify(proof, public_witness)It is difficult to achieve high performance due to the nature of Python and there are still many unoptimized code (ie. using naive implementation) in the current implementation.
Nevertheless, this library tries its best to achieve high performance as possible by utilizing Rust bindings via pyo3 as a backend for all primitives computation based from arkworks-rs/algebra libraries.
Note that running zksnake via pypy is slightly slower than Cpython.
The benchmark was done in Macbook M1 Pro (8 cores).
| Constraints | Compile | Setup | Prove | Verify |
|---|---|---|---|---|
| 1024 | 0.0154s | 0.7227s | 0.1201s | 0.0022s |
| 2048 | 0.0414s | 0.3480s | 0.2009s | 0.0019s |
| 4096 | 0.1341s | 0.5656s | 0.3827s | 0.0030s |
| 8192 | 0.5653s | 1.1019s | 0.7292s | 0.0019s |
| 16384 | 0.9669s | 2.5485s | 1.3710s | 0.0020s |
| 32768 | 2.8420s | 4.9742s | 2.6942s | 0.0020s |
| 65536 | 9.9637s | 8.8074s | 4.8914s | 0.0021s |
Requirements:
- python3 >= 3.9
- rust >= 1.77
Install maturin:
pip install maturin
Setup virtual environment:
python3 -m venv .venv
source .venv/bin/activate
Compile and install the editable module into venv:
maturin develop -r -E dev
Test the script:
python3 -m pytest tests