Tiramisu: Black-Box Simulation Extractable NIZKs in the Updatable CRS Model

• We propose a framework on lifting any non-blackbox simulation extractable SNARK to blackbox simulation SANRK in the updatable SRS model.
• This is useful when we want to model the schemes in the universal composable framework.
• We used the traditional technique of encrypting the witness to enable extraction without the need for the prover’s source code.
• However, since we are in the updatable setting, we had to come up with an encryption scheme that enables secret and public key upgradability.

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