#![allow(clippy::assertions_on_result_states)]
use curve25519_dalek::scalar::Scalar;
use libspartan::{InputsAssignment, Instance, SNARKGens, VarsAssignment, SNARK};
use merlin::Transcript;
use rand::rngs::OsRng;
#[allow(non_snake_case)]
fn produce_r1cs() -> (
usize,
usize,
usize,
usize,
Instance,
VarsAssignment,
InputsAssignment,
) {
let num_cons = 4;
let num_vars = 4;
let num_inputs = 1;
let num_non_zero_entries = 8;
let mut A: Vec<(usize, usize, [u8; 32])> = Vec::new();
let mut B: Vec<(usize, usize, [u8; 32])> = Vec::new();
let mut C: Vec<(usize, usize, [u8; 32])> = Vec::new();
let one = Scalar::one().to_bytes();
A.push((0, 0, one));
B.push((0, 0, one));
C.push((0, 1, one));
A.push((1, 1, one));
B.push((1, 0, one));
C.push((1, 2, one));
A.push((2, 2, one));
A.push((2, 0, one));
B.push((2, num_vars, one));
C.push((2, 3, one));
A.push((3, 3, one));
A.push((3, num_vars, Scalar::from(5u32).to_bytes()));
B.push((3, num_vars, one));
C.push((3, num_vars + 1, one));
let inst = Instance::new(num_cons, num_vars, num_inputs, &A, &B, &C).unwrap();
let mut csprng: OsRng = OsRng;
let z0 = Scalar::random(&mut csprng);
let z1 = z0 * z0; let z2 = z1 * z0; let z3 = z2 + z0; let i0 = z3 + Scalar::from(5u32);
let mut vars = vec![Scalar::zero().to_bytes(); num_vars];
vars[0] = z0.to_bytes();
vars[1] = z1.to_bytes();
vars[2] = z2.to_bytes();
vars[3] = z3.to_bytes();
let assignment_vars = VarsAssignment::new(&vars).unwrap();
let mut inputs = vec![Scalar::zero().to_bytes(); num_inputs];
inputs[0] = i0.to_bytes();
let assignment_inputs = InputsAssignment::new(&inputs).unwrap();
let res = inst.is_sat(&assignment_vars, &assignment_inputs);
assert!(res.unwrap(), "should be satisfied");
(
num_cons,
num_vars,
num_inputs,
num_non_zero_entries,
inst,
assignment_vars,
assignment_inputs,
)
}
fn main() {
let (
num_cons,
num_vars,
num_inputs,
num_non_zero_entries,
inst,
assignment_vars,
assignment_inputs,
) = produce_r1cs();
let gens = SNARKGens::new(num_cons, num_vars, num_inputs, num_non_zero_entries);
let (comm, decomm) = SNARK::encode(&inst, &gens);
let mut prover_transcript = Transcript::new(b"snark_example");
let proof = SNARK::prove(
&inst,
&comm,
&decomm,
assignment_vars,
&assignment_inputs,
&gens,
&mut prover_transcript,
);
let mut verifier_transcript = Transcript::new(b"snark_example");
assert!(proof
.verify(&comm, &assignment_inputs, &mut verifier_transcript, &gens)
.is_ok());
println!("proof verification successful!");
}