nova-snark 0.74.0

High-speed recursive arguments from folding schemes
Documentation 
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//! This module defines a collection of traits that define the behavior of a polynomial evaluation engine
//! A vector of size N is treated as a multilinear polynomial in \log{N} variables,
//! and a commitment provided by the commitment engine is treated as a multilinear polynomial commitment
use crate::{
  errors::NovaError,
  traits::{commitment::CommitmentEngineTrait, Engine},
};
use serde::{Deserialize, Serialize};

/// A trait that ties different pieces of the commitment evaluation together.
///
/// This trait is designed for use within a higher-level protocol transcript.
/// Before calling [`Self::prove`] or [`Self::verify`], the caller must bind the
/// complete evaluation instance (the commitment, evaluation point, and claimed
/// evaluation) to the transcript. Prover and verifier callers must use the same
/// domain separation and absorption order.
///
/// Standalone users are responsible for establishing this transcript context
/// before invoking either method. Implementations may rely on this context
/// rather than absorbing the evaluation instance again.
pub trait EvaluationEngineTrait<E: Engine>: Clone + Send + Sync {
  /// A type that holds the prover key
  type ProverKey: Clone + Send + Sync + Serialize + for<'de> Deserialize<'de>;

  /// A type that holds the verifier key
  type VerifierKey: Clone + Send + Sync + Serialize + for<'de> Deserialize<'de>;

  /// A type that holds the evaluation argument
  type EvaluationArgument: Clone + Send + Sync + Serialize + for<'de> Deserialize<'de>;

  /// A method to perform any additional setup needed to produce proofs of evaluations
  fn setup(
    ck: &<<E as Engine>::CE as CommitmentEngineTrait<E>>::CommitmentKey,
  ) -> Result<(Self::ProverKey, Self::VerifierKey), NovaError>;

  /// A method to prove the evaluation of a multilinear polynomial
  fn prove(
    ck: &<<E as Engine>::CE as CommitmentEngineTrait<E>>::CommitmentKey,
    pk: &Self::ProverKey,
    transcript: &mut E::TE,
    comm: &<<E as Engine>::CE as CommitmentEngineTrait<E>>::Commitment,
    poly: &[E::Scalar],
    point: &[E::Scalar],
    eval: &E::Scalar,
  ) -> Result<Self::EvaluationArgument, NovaError>;

  /// A method to verify the purported evaluation of a multilinear polynomials
  fn verify(
    vk: &Self::VerifierKey,
    transcript: &mut E::TE,
    comm: &<<E as Engine>::CE as CommitmentEngineTrait<E>>::Commitment,
    point: &[E::Scalar],
    eval: &E::Scalar,
    arg: &Self::EvaluationArgument,
  ) -> Result<(), NovaError>;
}