This is a pure Rust implementation of the PLONK proving system over BLS12-381

documentation page or run make doc or make doc-internal

PLONK

__

This library contains a modularised implementation of KZG10 as the default polynomial commitment scheme.

Usage

use dusk_plonk::prelude::*;
use rand_core::OsRng;

// Implement a circuit that checks:
// 1) a + b = c where C is a PI
// 2) a <= 2^6
// 3) b <= 2^5
// 4) a * b = d where D is a PI
// 5) JubJub::GENERATOR * e(JubJubScalar) = f where F is a Public Input
#[derive(Debug, Default)]
pub struct TestCircuit {
    a: BlsScalar,
    b: BlsScalar,
    c: BlsScalar,
    d: BlsScalar,
    e: JubJubScalar,
    f: JubJubAffine,
}

impl Circuit for TestCircuit {
    const CIRCUIT_ID: [u8; 32] = [0xff; 32];
    fn gadget(
        &mut self,
        composer: &mut StandardComposer,
    ) -> Result<(), Error> {
        let a = composer.add_input(self.a);
        let b = composer.add_input(self.b);
        // Make first constraint a + b = c
        composer.poly_gate(
            a,
            b,
            composer.zero_var(),
            BlsScalar::zero(),
            BlsScalar::one(),
            BlsScalar::one(),
            BlsScalar::zero(),
            BlsScalar::zero(),
            Some(-self.c),
        );
        // Check that a and b are in range
        composer.range_gate(a, 1 << 6);
        composer.range_gate(b, 1 << 5);
        // Make second constraint a * b = d
        composer.poly_gate(
            a,
            b,
            composer.zero_var(),
            BlsScalar::one(),
            BlsScalar::zero(),
            BlsScalar::zero(),
            BlsScalar::one(),
            BlsScalar::zero(),
            Some(-self.d),
        );

        let e = composer.add_input(self.e.into());
        let scalar_mul_result = composer
            .fixed_base_scalar_mul(e, dusk_jubjub::GENERATOR_EXTENDED);
        // Apply the constrain
        composer.assert_equal_public_point(scalar_mul_result, self.f);
        Ok(())
    }
    fn padded_circuit_size(&self) -> usize {
        1 << 11
    }
}

// Now let's use the Circuit we've just implemented!

let pp = PublicParameters::setup(1 << 12, &mut OsRng).unwrap();
// Initialize the circuit
let mut circuit = TestCircuit::default();
// Compile the circuit
let (pk, vd) = circuit.compile(&pp).unwrap();
// Prover POV
let proof = {
    let mut circuit = TestCircuit {
        a: BlsScalar::from(20u64),
        b: BlsScalar::from(5u64),
        c: BlsScalar::from(25u64),
        d: BlsScalar::from(100u64),
        e: JubJubScalar::from(2u64),
        f: JubJubAffine::from(
            dusk_jubjub::GENERATOR_EXTENDED * JubJubScalar::from(2u64),
        ),
    };
    circuit.gen_proof(&pp, &pk, b"Test").unwrap()
};
// Verifier POV
let public_inputs: Vec<PublicInputValue> = vec![
    BlsScalar::from(25u64).into(),
    BlsScalar::from(100u64).into(),
    JubJubAffine::from(
        dusk_jubjub::GENERATOR_EXTENDED * JubJubScalar::from(2u64),
    )
    .into(),
];
circuit::verify_proof(
    &pp,
    &vd.key(),
    &proof,
    &public_inputs,
    &vd.pi_pos(),
    b"Test",
).unwrap();

Features

This crate includes a variety of features which will briefly be explained below:

  • alloc: Enables the usage of an allocator and with it the capability of performing Proof constructions and verifications. Without this feature it IS NOT possible to prove or verify anything. Its absence only makes dusk-plonk export certain fixed-size data structures such as Proof which can be useful in no_std envoirments where we don't have allocators either.
  • std: Enables std usage as well as rayon parallelisation in some proving and verifying ops. It also uses the std versions of the elliptic curve deps, which utilises the parallel feature from dusk-bls12-381. By default, this is the feature that comes enabled with the crate.
  • trace: Enables the Circuit debugger tooling. This is essentially the capability of using the StandardComposer::check_circuit_satisfied function. The function will output information about each circuit gate until one of the gates does not satisfy the equation, or there are no more gates. If there is an unsatisfied gate equation, the function will panic and return the gate number.
  • trace-print: Goes a step further than trace and prints each gate component data, giving a clear overview of all the values which make up the circuit that we're constructing. The recommended method is to derive the std output, and the std error, and then place them in text file which can be used to efficiently analyse the gates.
  • canon: Enables canonical serialisation for particular data structures, which is very useful in integrating this library within the rest of the Dusk stack - especially for storage purposes.

Documentation

There are two main types of documentation in this repository:

  • Crate documentation. This provides info about all of the functions that the library provides, as well as the documentation regarding the data structures that it exports. To check this, please feel free to go to the documentation page or run make doc or make doc-internal.

  • Notes. This is a specific subset of documentation which explains the key mathematical concepts of PLONK and how they work with mathematical demonstrations. To check it, run make doc and open the resulting docs, which will be located under /target with your browser.

Performance

Benchmarks taken on Intel(R) Core(TM) i9-9900X CPU @ 3.50GHz For a circuit-size of 2^16 constraints/gates:

  • Proving time: 5.46s
  • Verification time: 9.34ms. (This time will not vary depending on the circuit-size.)

Acknowledgements

  • Reference implementation AztecProtocol/Barretenberg
  • FFT Module and KZG10 Module were taken and modified from zexe/zcash and scipr-lab, respectively.

Licensing

This code is licensed under Mozilla Public License Version 2.0 (MPL-2.0). Please see LICENSE for further info.

About

Implementation designed by the dusk team.

Contributing

  • If you want to contribute to this repository/project please, check CONTRIBUTING.md
  • If you want to report a bug or request a new feature addition, please open an issue on this repository.
Issues

Collection of the latest Issues

xevisalle

xevisalle

area:cryptography
0

Describe what you want implemented We need to rebase this repository to Plonk, as it currently includes the PlonkUp implementation that has been copied to the /plonkup repo.

Describe "Why" this is needed To separate both implementations, and being able to benchmark the pairs plonk+poseidon and plonkup+zelbet.

moCello

moCello

team:Core
0

Describe what you want implemented Eliminate expect in append_output_witness by propagating an error if q_o is 0.

Describe "Why" this is needed A malicious user can crash a plonk server by submitting a wrong proof.

Describe alternatives you've considered Set a constant when q_o happens to be zero. Changing the signature is preferable because it will reflect what happens internally: any proof request where q_o is zero is invalid.

Additional context First mentioned by @vlopes11 here

ZER0

ZER0

fix:bug
0

Describe the bug Code coverage fails because it takes the wrong commit for master, see: https://github.com/dusk-network/plonk/pull/668

The current master at that point in time was: https://github.com/dusk-network/plonk/commit/d8ef7908db1f4995883e5e64db8d68e9cc343483 (just pushed)

But the code coverage reports: https://github.com/dusk-network/plonk/commit/8d01a94eb604121ad84d77797cbf7e5af625af40 (pushed 20 days ago)

This bug leads to code coverage failures even with small changes, making the code coverage totally unreliable and unpredictable. To Reproduce See the description.

Expected behaviour Code Coverage should take the proper commit.

Logs/Screenshot N/A

Platform N/A

Additional context N/A

moCello

moCello

team:Core
0

Describe what you want implemented The polynomial z_2 in round 3 needs a permutation challenge theta to be computed. This seems to not be implemented yet.

Describe "Why" this is needed So that the implementation matches the paper.

Describe alternatives you've considered none

Additional context NA

moCello

moCello

good first issue
0

Describe what you want implemented Remove the bit_iterator macro.

Describe "Why" this is needed As far as I can see we only invoke the macro once to create BitIterator8 so I don't see the need to have a macro for it. Creating BitIterator8 directly is much clearer.

Describe alternatives you've considered Leave as is.

Additional context NA

moCello

moCello

area:documentation
0

Describe what kind of specification you want to have created Under the documentation module, add articles that help understand PlonK, e.g.:

  • Zero Knowledge Proofs
  • Finite fields of elliptic curve points
  • Elliptic curve pairings
  • PLONK basics
    • circuit/gates
    • polynomials
    • statement & proof systems
  • Kate commitments
vlopes11

vlopes11

status:minor
0

Describe what you want implemented Every constraint appended to a composer must also push its Constraint instance to an internal vector of constraints.

This will deprecate the multiple selectors that are stored individually as well as self.n that can be trivially replaced by self.constraints.len()

After this is implemented, we should split the sparse store of public inputs by a single vector that will contain the constraint positions that are included with a public input. The value of the public input should not be evaluated because they can be 0 - the criteria is to include a public input index whenever the constraint is constructed with Constraint::public. This sparse public input indexes will be used for the composition of VerifierData. The Constraint should keep the dense public inputs set normally, using zeroes when required.

Describe "Why" this is needed The selectors count must always be equal. This is handled manually in the code and is the source of potential problems. One example is the inclusion of the plonkup that was far harder than necessary because we needed to update every different part of the codebase that added at least one selector.

Also, this will greatly facilitate future API improvements regarding the wired witnesses and circuit description.

Describe alternatives you've considered N/A

Additional context N/A

ZER0

ZER0

team:Core
0

Currently there is a lot of code repetition and complexity under proof_system/widget modules, it should be definitely possible to reduce and improve the ergonomics of the code.

ChihChengLiang

ChihChengLiang

fix:bug
0

What's wrong

The variable k in the check_circuit_satisfied should check if constraints related to q_fixed_group_add and q_variable_group_add selectors are satisfied, but the check is unimplemented now.

How can we fix it

Add qfixed and qvar checks to the variable k

CPerezz

CPerezz

area:end-user-utility
0

Associated trait-constants are a problem when we need to return from functions things like & impl Circuit. Since the trait is not object safe anc we cannot make use of dynamic dispatch which is a big issue that we-ve faced a couple of times so far.

So the plan for the next release, is to change the impl for the CIRCUIT and break the API replacing the CIRCUIT_ID const by a simple associated function that allows object safety and therefore dynamic dispatch.

DreamWuGit

DreamWuGit

status:minor
1

from what I see code , both in pre process and prove stage, lots of polynomials need to be committed,, such as : " let q_m_poly_commit = commit_key.commit(&q_m_poly).unwrap_or_default(); let q_l_poly_commit = commit_key.commit(&q_l_poly).unwrap_or_default(); let q_r_poly_commit = commit_key.commit(&q_r_poly).unwrap_or_default(); let q_o_poly_commit = commit_key.commit(&q_o_poly).unwrap_or_default(); let q_c_poly_commit = commit_key.commit(&q_c_poly).unwrap_or_default(); let q_4_poly_commit = commit_key.commit(&q_4_poly).unwrap_or_default(); let q_arith_poly_commit = commit_key.commit(&q_arith_poly).unwrap_or_default(); let q_range_poly_commit = commit_key.commit(&q_range_poly).unwrap_or_default(); let q_logic_poly_commit = commit_key.commit(&q_logic_poly).unwrap_or_default(); "

these polys are independent, do it in multi threads in parallel will improve the performance regarding this type operation, this is what I think intuitively ! anybody take a look at such idea ? is there something I'm missing ?

thanks Dream

CPerezz

CPerezz

status:minor
0

We usually store multiple Evaluations inside the same structure (ProverKey is an example of that). It's really sub-optimal to store the same EvaluationDomain across all of the Evaluations of the structure.

Therefore, we should consider how viable and logical is the removal.

CPerezz

CPerezz

need:help
0

All true rust types know their size and alignment, which dyn Trait types accomplish using their vtable.

In consequence, one could build a TinyBox<T: Sized> type that allocated when size_of_val(&T) > size_of::<usize>() but otherwise stored T internally, and then TinyBox<dyn Trait> could actually work correctly by using size_of_val(&self), which only accesses the vtable, not the actual self data pointer.

We could then make TinyBox work even without alloc, simply by making its non-alloc form panic when size_of_val(&T) > size_of::<usize>().

At this point, if one has a no_std compatable Error trait then one could rebuild the entire trait infrastructure of std::io on top of this trait. This gives you Result<T,dyn Error> which works even without alloc for small enums, OS ernos, etc., but not large complex error types with backtrace allocations, etc.

I've zero time to implement this, but if anyone gets interested then I'm happy to give some pointers.

cc https://github.com/rust-lang/project-error-handling/issues/20

Originally posted by @burdges in https://github.com/dusk-network/plonk/issues/343#issuecomment-777661334

CPerezz

CPerezz

area:end-user-utility
1

After we started to release new versions of this crate. The examples folder was removed since we weren't able to keep it up to date due to the refactors we were performing.

I think it's a good source of knowledge for the newcomers to the repo and also allows the users to see how to interact with the library on the "recommended way".

CPerezz

CPerezz

area:constraint_system
0

We have places in our code where the Variable type holds a value that can be mapped securely to a JubJubScalar. See for example: https://github.com/dusk-network/plonk/blob/master/src/constraint_system/ecc/scalar_mul/variable_base/mod.rs#L11-L34

Therefore it's important to be sure when we can or cannot use one of these variables for ECC ops purposes.

There is one thing which is actually not doable (directly using PLONK) which is the fact of transforming a BlsScalar into a JubJubScalar after hashing in order to use the result of the hash as the JubJubScalar used to perform the scalar mul.

To do so, we will need to refactor the Variable struct to differenciate between Bls and JubJub and also, implement a gate (without a commitment requirement) that will perform this operation returning a different variant of the enum.

The possible conversions are:

  • Variable::JubJub -> Variable::Bls: (No cost or gates involved (FREE))
  • Variable::Bls -> Variable::JubJub: We need to perform what has been now included inside of this PR also replacing the hardcoded constant by a constant in this crate.
kevaundray

kevaundray

status:minor
0

To simplify the API for public/private variables; Add a gate for each public variable constraining it to a witness, then use the witness in the gates instead of a public variable slot for each gate.

CPerezz

CPerezz

area:cryptography
0
CPerezz

CPerezz

team:Core
1

In the current Composer API that we publicly expose, we have a lot of gate-functions that require the user to input +6 or +7 fields.

As mentioned by @ZER0 and @vlopes11 this is quite confusing, specially if you're not familiar with the library.

Therefore, it would be nice to discuss which would be a good approach (if there is) to solve this problem.

CPerezz

CPerezz

good first issue
0

It would be nice to avoid having the Vec inside of the Polynomial struct as pub and instead having it private and implement Iter and IntoIter traits for it.

Versions

Find the latest versions by id

v0.9.1 - Jan 05, 2022

[0.9.1] - 05-01-22

Added

  • Add support for rendering LaTeX in the docs #630
  • Add append_public_witness to TurboComposer. #654

v0.8.2 - Sep 17, 2021

[0.8.2] - 17-09-21

Added

  • Add From extended point to PublicInputValue #573

Fixed

  • Fix the document references and typos #533
  • Fix if condition to match #545

v0.8.1 - Jun 07, 2021

[0.8.1] - 07-06-21

Added

  • Add zero_var to composer #526
  • Add add_affine_to_circuit_descriptionto composer #534

Removed

  • Remove external_doc and nightly feature #536

v0.8.0 - May 03, 2021

[0.8.0] - 03-05-21

Added

  • Add alloc feature to the crate #345
  • Add rayon behind std feature to boost proving performance #512
  • Add rayon behind std feature to boost verifying performance #514
  • Add alternative getters for OpeningKey & CommitKey in PublicParameters #510

Changed

Removed

  • Remove trimming step from Circuit::Verify_proof #510

v0.7.0 - Apr 06, 2021

[0.7.0] - 06-04-21

Added

  • Implement VerifierData structure. #466

Fixed

  • Fix circuit debuggger compilation issues. #488
  • Fix import paths for lib components. #489

v0.6.1 - Mar 12, 2021

[0.6.1] - 12-03-21

Changed

  • Change PublicParameters::trim visibility to pub. #460
  • Change StandardComposer::construct_dense_pi_vec visibility to pub.#461

v0.6.0 - Mar 11, 2021

[0.6.0] - 11-03-21

Added

  • Implement dusk_bytes::Serializable for all possible structures that need serde. #352
  • Introduced a new type that unifies the Public Inputs PublicInputValue. #416
  • Impl padded_circuit_size for VerifierKey #351
  • Impl a generic method that can verify Proofs of any Circuit. #396

Removed

  • Remove Canon impl for Proof. #450
  • Remove serde support completely from the repo. #353
  • Removed previous implementations attached to PublicInputValues. #416
  • Deprecated anyhow and thiserror. #343
  • Remove serialisation module and use single serialization fn's. #347
  • Remove uncessary match branch for var_c #414
  • Remove legacy fns and move to test modules the only-for-testing ones. #434

Changed

  • Constrained as much as possible the visibility of fns, structs and it's fields #438]
  • Store the sparse repr of the PI and positions in a BTreeMap #427
  • Transcript Init and trim size are associated constants of the Circuit trait #351
  • Replace collections::HashMap by hashbrown::HashMap. #424
  • Circuit trait now only requires padded_circuit_size for trimming. #351
  • Remove verify_proof & build_pi from Circuit. #396
  • Update API naming conventions to be standard across the crate. #354
  • Updated the native errors to all originate from the same enum. #343

v0.5.1 - Feb 02, 2021

[0.5.1] - 02-02-21

Changed

  • Implement Clone for PublicParameters #383

v0.5.0 - Jan 27, 2021

[0.5.0] - 27-01-21

Changed

  • Upgrade canonical to v0.5 (#371)
  • Upgrade dusk-bls12_381 to v0.6
  • Upgrade dusk-jubjub to v0.8

v0.4.0 - Jan 26, 2021

[0.4.0] - 26-01-21

Fixed

  • Heavy data structures from unchecked #332

Changed

  • Refactored to/from_bytes criteria for some structs (#333)
  • API breaking - Implement to/from unchecked bytes for public parameters (#332)

v0.3.6 - Dec 21, 2020

[0.3.6] - 17-12-20

Added

  • To/From bytes impl for PublicInput.

Changed

  • Changed compute_permutation_poly to simpler version.

v0.3.5 - Nov 25, 2020

[0.3.5] - 25-11-20

Changed

  • Changed Proof & ProofEvaluations byte conversion fn signatures.

Added

  • Implemented Canon for Proof.

v0.3.4 - Nov 09, 2020

[0.3.4] - 02-11-20

Changed

  • dusk-jubjub update to v0.5.0 with API renaming
  • dusk-bls12_381 update to v0.3.0 with API renaming

v0.3.3 - Nov 03, 2020

[0.3.3] - 02-11-20

Added

  • canon feature to manage Canon derivations usage in ecc libs.

Changed

  • dusk-jubjub update to v0.4.0
  • dusk-bls12_381 update to v0.2.0

v0.3.2 - Nov 02, 2020

[0.3.2] - 29-10-20

Changed

  • dusk-bls12_381 update to v0.1.5
  • dusk-jubjub update to v0.3.10
  • Fixes #311 - big_mul and big_mul_gate documentation nit.

v0.3.1 - Oct 05, 2020

[0.3.1] - 05-10-20

Added

  • Method to change the trim_params_size for the Circuit trait.

v0.3.0 - Oct 05, 2020

[0.3.0] - 05-10-20

Changed

  • Circuit trait API & usability improvements (#313)

v0.2.11 - Sep 29, 2020

[0.2.11] - 29-09-20

Changed

  • Now Circuit inputs are set in the circuit structure as Option<T>.
  • Make PublicInput::value() fn public.
  • Make pi_builder return Result<T>
  • Refactored examples for the Circuit trait impl according to the new changes.

Removed

  • Removed CircuitInputs from the crate.

v0.2.10 - Sep 23, 2020

[0.2.10] - 23-09-20

Added

  • Added CircuitBuilder trait and a example for it.

v0.2.9 - Sep 13, 2020

[0.2.9] - 11-09-20

Added

  • Added ProverKey & Verifierkey to the public API as exported types.

Changed

  • Use dusk-bls12_381 v0.1.4.
  • Use dusk-jubjub v0.3.8.

v0.2.8 - Aug 26, 2020

[0.2.8] - 25-08-20

Added

  • Add a variable_base_scalar_mul method using a variable base curve add gate.

Changed

  • ecc::scalar_mul now named fixed_base_scalar_mul

v0.2.7 - Aug 13, 2020

Added

  • Anyhow & thiserror for error handling support.
  • Serialisation methods for the crate public structures & serde support.

Removed

  • failure for error support since has been deprecated.

Changed

  • add_witness_to_circuit_description requires now just to send a Scalar and returns a constant & constrained witness Variable.
  • Update add_witness_to_circuit_description fn sig (#282, #284)
  • dusk-jubjub version updated to 0.3.6

v0.2.6 - Aug 11, 2020

[0.2.6] - 03-08-20

Changed

  • Make public inputs vector publicly accessible

v0.2.5 - Aug 11, 2020

[0.2.5] - 31-07-20

Changed

  • ECC Point from ecc:scalar_mul should have its attributes exposed.

v0.2.4 - Jul 30, 2020

  • Changed dusk-jubjub tov0.3.5 to fix Fr rnd gen

v0.2.3 - Jul 29, 2020

[0.2.2] - 29-07-20

Changed

  • Changed dusk-jubjub version to v0.3.4 to update dhke protocol.

v0.2.2 - Jul 25, 2020

[0.2.2] - 25-07-20

Added

  • Method to create constrained witness values. @CPerezz

Changed

  • Visibility of the Proof::verify() fn to pub(crate). @CPerezz
  • Changed dusk-jubjub version to v0.3.3 since v0.3.2 was yanked.

v0.2.1 - Jul 24, 2020

[0.2.1] - 24-07-20 [yanked]

Added

  • Method to create constrained witness values. @CPerezz

Changed

  • Visibility of the Proof::verify() fn to pub(crate). @CPerezz

v0.2.0 - Jul 20, 2020

[0.2.0] - 20-07-20

Added

  • Prover and Verifier abstraction @kevaundray
  • Error handling and custom errors @CPerezz
  • Add prelude file @CPerezz
  • Add identity separation challenge to each identity. @kevaundray
  • Decouple Prover and Verifier Key @kevaundray
  • Remove Preprocessed circuit @kevaundray
  • Implement ECC gate @kevaundray
  • Add math-related docs @Bounce23
  • Add identity separation challenge to each identity @kevaundray

Changed

  • Widget splitting to modularize the codebase @kevaundray

Fixed

  • Bug in "front-end" assertions in logic_constraint gates @CPerezz
  • Broken links in the docs @CPerezz

Removed

  • Serde support for the time being.

v0.1.0 - Apr 25, 2020

[0.1.0] - 25-04-20

Added

  • PLONK algorithm implementation.
  • Example folders.
  • Doc notes with kateX.
  • KZG10 polynomial commitment scheme implementation.
  • fft module with Polynomial ops implemented.
  • Proof system module.

Changed

Fixed

Removed

Information - Updated May 23, 2022

Stars: 242
Forks: 61
Issues: 29

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