Zero Knowledge Proofs, ZKPs, is a method that allows a prover to proof a statement to a verifier without having to reveal it.

The following repository defines a:

Visual ZKP proof generator

Main script (Python): main.py
Sequence verification generator (Python): verification_hash.py
A Polygon smart contract (https://polygon.technology/) with the NFT verification logic /verification

main.py

ZKP visual proof generator given two sequences of uint[5] created by two different users. The outputs of the script are:

A 5 by 5 image with pixels correspond to sha256(sequence) mod 255.
Noise is added to each user's sequence before the hash creation.

The script can be triggered by runnning:

docker build . -t zkp

docker run -v $(pwd)/image:/hash_mechanism/image -it zkp bash

The previous command will exec you into the created Docker container.

python main.py '{"user1": [6, 7, 9, 10, 12], "user2": [1, 2, 3, 8, 7]}'

{}: Dictionary of users' sequences

It will save the proof.png at current_directory/image in the host computer.

verification_hash.py

Cryptographic verification sequence generator given the original image and the noise used by main.py (central oracle able to generate the global proof).

The script can be triggered by runnning:

docker build . -t zkp

docker run -v $(pwd)/image:/hash_mechanism/image -it zkp bash

The previous command will exec you into the created Docker container.

python verification_hash.py '[6, 7, 9, 10, 12]' 1

[]: Sequence

Int: Noise of the user

/verification

NFT ERC721 verification smart contract on Polygon.

Main two functionalities of the smart contract are:

creation and minting of an NFT with its corresponding uint[5][5] values per pixel.
verification of a given sequence over a token.

Smart contract support libraries:

npm install -g truffle
npm install @openzeppelin/contracts

For local development mnemonic seed phrase: .env

LOCAL DEVELOPMENT WITH GANACHE

Install Ganache for local development: npm install -g ganache-cli

ganache-cli

Truffle migrate (Deploys smart contract on local test network)

truffle migrate --config=truffle-config.polygon.js --network=development

Truffle local console

truffle console --config=truffle-config.polygon.js --network=development

Steps in console for test:

let instance = await VerifierNFT.at("YOUR_CONTRACT_ADDRESS_HERE")

Mint NFT:

await instance.mint("YOUR_WALLET_ADDRESS", "YOUR_METADATA_URI", uint[5][5] sequences)

Verify sequence on a given NFT id:

await instance.verify(sequenceToVerify, tokenID)

TokenID points to the NFT with the global proof.

Reference tutorial to deploy on testnet instead of local net: https://blog.paulmcaviney.ca/how-to-mint-an-nft-on-polygon

MUMBAI POLYGON TESTNET DEVELOPMENT

Define .secret with wallet secret key to create the contract and do NOT commit the information online, as the key could be stolen.
Define Polygon scan token under truffle-config.json
To obtain tokens for deployment on the Mumbai Polygon testnet please go to:

https://faucet.polygon.technology/
truffle compile
Deployment on the Mumbai testnet: truffle migrate --network polygon
Console to mint and verify over deployed contract on Mumbai testnet: truffle console --network polygon

Steps to test: