crates/stark/src/oods.rs:31:18: attempt to subtract with overflow

[tdelabro]

          I changed my `cpu_air_params.json` to `"fri_step_list": [0, 4, 4, 4, 4]"` and it now crashes later in the verification:

At crates/stark/src/oods.rs:31:18 which is:

pub fn verify_oods<Layout: LayoutTrait>(
    oods: &[Felt],
    interaction_elements: &Layout::InteractionElements,
    public_input: &PublicInput,
    constraint_coefficients: &[Felt],
    oods_point: &Felt,
    trace_domain_size: &Felt,
    trace_generator: &Felt,
) -> Result<(), OodsVerifyError> {
    let composition_from_trace = Layout::eval_composition_polynomial(
        interaction_elements,
        public_input,
        &oods[0..oods.len() - 2], // < here
        constraint_coefficients,
        oods_point,
        trace_domain_size,
        trace_generator,
    )?;
    ...
}

Originally posted by @tdelabro in #54 (comment)

[tdelabro]

Could it be that my annotations look like that:

		"V->P: /cpu air/STARK/Out Of Domain Sampling/OODS values: Evaluation point: Field Element(0x6554169f2c8b8fa0f8b0c2f65af48039f64ad47f2fd90caaa2bb808f600f829)",
		"P->V[96:128]: /cpu air/STARK/Out Of Domain Sampling/OODS values: 0: Field Element(0x40536e9e9158351e084b9ec5f9831c96969e4efd8f0b56f8532f377d2988483)",
		"P->V[128:160]: /cpu air/STARK/Out Of Domain Sampling/OODS values: 1: Field Element(0x369e29b182cf9accf1868d724708ba83a462c4c8fa425d0c9d5c956a43ec75a)",
		"P->V[160:192]: /cpu air/STARK/Out Of Domain Sampling/OODS values: 2: Field Element(0x2e553a9831fa0df8fa5d1029d152a7dcda95c310aa6bd5a9fe5b650abce5078)",
		"P->V[192:224]: /cpu air/STARK/Out Of Domain Sampling/OODS values: 3: Field Element(0x1f179c246f2d0347d1cad76a75781ef805854f85b3fe933c5179a0131a6b0d6)",

while your code expect the odds prefix to be "STARK/Out Of Domain Sampling/OODS values"
see proof_parser/src/annotations/annotation_kind.rs

            Annotation::OodsValues => PrefixAndKind {
                prefix: "STARK/Out Of Domain Sampling/OODS values".to_string(),
                kinds: AnnotationKinds::FieldElements,
            },

[tdelabro]

Yup, I think something is wrong in the parsing because I printed my oods:

    let x = stark_proof.unsent_commitment.oods_values;
    panic!("{:?}", x);

and got []

[Okm165]

do u have latest stone built?
i am asking this Q latest stone is annotating oods values like this
https://github.com/iosis-tech/swiftness/blob/main/examples/proofs/recursive/cairo0_stone5_example_proof.json#L16
your annotations way looks old

[tdelabro]

I think I build it from source: https://github.com/starkware-libs/stone-prover
From a non-released commit:

cpu_air_prover -version
cpu_air_prover version INVALID_NAME-INVALID_PROOF_HASH-INVALID_COMMIT

Which version do you recommend I use?

[Okm165]

Oh It is not version issue latest Stone v3 is fine
What u are missing is the correct proof params especially "verifier_friendly_channel_updates" : true
Take a look at the proof params in the repo guide: https://github.com/iosis-tech/swiftness/blob/main/examples/proofs/cpu_air_params.json

[tdelabro]

Mine is currently:

{
    "field": "PrimeField0",
    "stark": {
        "fri": {
            "fri_step_list": [
                0,
                4,
                4,
                4,
                4
            ],
            "last_layer_degree_bound": 32,
            "n_queries": 18,
            "proof_of_work_bits": 30
        },
        "log_n_cosets": 4
    },
    "use_extension_field": false
}

What else should I change?

[Okm165]

Just copy json from my link and adjust fri layers for ur case

[tdelabro]

Is this the only configuration verifiable with swiftness? Or is there some room for configuration here?

[tdelabro]

I tryied different mixed fri but always get the same error:

Caused by:
    0: OodsVerifyError Error
    1: oods invalid 709992957254620831002252392826336286100946637269575755219814514419612025930 - 1868104729289279686881179178362914385993703678119283254310630101746102206724

(actual values may vary)

Last I used is:

{
    "field": "PrimeField0",
    "channel_hash": "poseidon3",
    "commitment_hash": "blake256_masked248_lsb",
    "n_verifier_friendly_commitment_layers": 10,
    "pow_hash": "blake256",
    "statement": {
        "page_hash": "pedersen"
    },
    "stark": {
        "fri": {
            "fri_step_list": [
                0,
                4,
                4,
                4,
                2
            ],
            "last_layer_degree_bound": 128,
            "n_queries": 18,
            "proof_of_work_bits": 24
        },
        "log_n_cosets": 2
    },

    "use_extension_field": false,
    "verifier_friendly_channel_updates": true,
    "verifier_friendly_commitment_hash": "poseidon3"
}

[tdelabro]

should n_verifier_friendly_commitment_layers be equal to the sum of fri_step_list?

I tried it (setting it to 14 while keeping the last config I showed) and it failed

[Okm165]

this command should verify proof with above configuration (i saw u use starknet layout in the prev proof)
cargo run --release --bin swiftness --features starknet,blake2s_248_lsb,stone6 --no-default-features -- --proof your_proof.json

[Okm165]

Given the correctly generated proof the verifier fails to verify with error Error: PublicInputError(MaxSteps)
This is due to this check failing https://github.com/iosis-tech/swiftness/blob/main/crates/air/src/layout/starknet/mod.rs#L525

More context:
This is due to verifier expects certain public memory fingerprint.
When we generate the proofs straight from Cairo1 the rust cairo-vm in proof_mode
has different memory fingerprint then python-vm in proof_mode

I created this #56 that just removes the vm specific final_pc check u can use it for now

Your proof is verified succesfully on branch https://github.com/iosis-tech/swiftness/tree/fix/final_pc
cd cli && cargo run --release --bin swiftness --features starknet,blake2s_248_lsb,stone6 --no-default-features -- --proof proof.json

[Okm165]

cargo run --release --bin swiftness --features starknet,blake2s_248_lsb,stone6 --no-default-features -- --proof proof.json 
    Finished `release` profile [optimized] target(s) in 0.04s
     Running `target/release/swiftness --proof proof.json`
(0x4ce57f0e77c4eb88291d6f5eebc334d2709efc403421dced632f24f48455b43, 0x2c97a976cb90de9489adf4a4b79a1e5661ad9ab3ac6a254f88f5b795ee6412)