akharawita/poc-zkf-dapp

Getting Started Write circuit with Circom

• Install the Circom install
• Writing circuits in folder circuits compile to circuites/build folder
• Compiling circom ./withdraw_multiplier.circom --r1cs --wasm --sym --c -o build
• Download the "Powers of Tau trusted setup file" select powersOfTau28_hez_final_13.ptau file from here and place it in the circuites folder
• Back to root folder and Run yarn snarkjs plonk setup ./circuits/build/withdraw_multiplier.r1cs ./circuits/powersOfTau28_hez_final_08.ptau ./circuits/build/proving_key.zkeyto generate thegenerate proving key file that we will use to generate the proof using the R1CS and ptau

Export the verifier contract from the proving key

• Run yarn snarkjs zkey export solidityverifier ./circuits/build/proving_key.zkey ./contracts/src/WithdrawVerifier.sol to generate the contracts/src/WithdrawVerifier.sol file

Create the proof

• Run yarn snarkjs plonk fullprove circuits/witness.json circuits/build/withdraw_multiplier_js/withdraw_multiplier.wasm circuits/build/proving_key.zkey circuits/build/proof.json circuits/build/public.json to generate the proof.json and public.json file

** Optional step ** We need a verification key that can be generated from the proving key to verify the proof. Here’s how to get that:

• Run yarn snarkjs zkey export verificationkey circuits/build/proving_key.zkey circuits/build/verification_key.json to generate the verification_key.json file

Verify the proof

We use the this command to verify the proof, passing in the verification_key we exported earlier.

If all is well, you should see that OK has been outputted to your console. This signifies the proof is valid.

• Run yarn snarkjs plonk verify circuits/build/verification_key.json circuits/build/public.json circuits/build/proof.json to verify the proof

Similate a verification call

• Run yarn snarkjs zkey export soliditycalldata circuits/build/public.json circuits/build/proof.json to cut and paste the result directly in the verify function in the WithdrawVerifier.sol contract

And voila! That's all there is to it :)

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Contract Testing

forge install
forge test --match-path ./test/SimpleTornado.t.sol -vvv

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Refs

• https://github.com/iden3/rollup/blob/master/circuits/rollup.circom
• https://hackernoon.com/protect-yourself-from-identity-theft-by-using-zero-knowledge-proof-solidity-and-ethereum
• https://github.com/zkBob/zkbob-contracts
• https://github.com/nalinbhardwaj/snarky-sudoku/blob/main/client/lib/util.ts

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This is a Next.js project bootstrapped with create-next-app.

Getting Started

First, run the development server:

• Copy proving_key.zkey and withdraw_multiplier.wasm to the public/zksnarks folder

npm run dev
# or
yarn dev
# or
pnpm dev
# or
bun dev

Open http://localhost:3000 with your browser to see the result.

You can start editing the page by modifying app/page.tsx. The page auto-updates as you edit the file.

This project uses next/font to automatically optimize and load Inter, a custom Google Font.

Learn More

To learn more about Next.js, take a look at the following resources:

• Next.js Documentation - learn about Next.js features and API.
• Learn Next.js - an interactive Next.js tutorial.

You can check out the Next.js GitHub repository - your feedback and contributions are welcome!

Deploy on Vercel

The easiest way to deploy your Next.js app is to use the Vercel Platform from the creators of Next.js.

Check out our Next.js deployment documentation for more details.