/zkcard-contracts

Primary LanguageSolidity

Zero-Knowledge Card Game

Introduction

Findora provides a zero-knowledge card protocol via precompiled smart contract for on-chain games. Thanks to the support of Geometry Research, Findora is able to bring this powerful tool to game developers in the web3 space.

Features

  • Define custom cards.

    Developers can define their own number of cards, suites and values.

  • Hide card values.

    The card values are encrypted with the aggregate key and players hide the encrypted values from each other.

  • Zero-knowledge card shuffling.

    The shuffling is done off-chain with fair randomness by every player using zero-knowledge proofs.

  • Zero-knowledge card revealling.

    No sub-group of players can see the card values unless all players agree to reveal the cards.

  • Cheating prevention.

    Each secret off-chain computation is proven in zero-knowledge proof and verified by on-chain smart contract.

Use cases

The protocol allows any on-chain card-like games including

  • Poker games
  • Casino games
  • Board games
  • Turn-based games
  • Card trading games
  • Any game having card models

API list

Developers need only six game APIs to build games on top of Findora platform. Pleae checkout Solidity interface for more details.

function verifyKeyOwnership(bytes params, bytes pubKey, bytes memo, bytes keyProof) external view returns (bool);
function computeAggregateKey(bytes[] pubKeys) external view returns (bytes memory);
function mask(bytes params, bytes sharedKey, bytes encoded) external pure returns (bytes memory);
function verifyShuffle(bytes params, bytes sharedKey, bytes[] curDeck, bytes[] newDeck, bytes shuffleProof) external view returns (bool);
function verifyReveal(bytes params, bytes pubKey, bytes revealToken, bytes masked, bytes revealProof) external view returns (bool);
function reveal(bytes[] revealTokens, bytes masked) external view returns (bytes memory);

Contract address

Above APIs will be provided via precompiled smart contract on game side chain (GSC).

Network Contract Address
GSC Mainnet 0x0000000000000000000000000000000000003000
GSC Testnet 0x0000000000000000000000000000000000003000

Starter kit and examples

Build your games on top of example game contracts to save time and effort. The starter kit includes

Contract Description
GameInstance.sol An example of basic game contract for general card game
OneTimeDrawInstance.sol An example of game contract where players draw all their hands at once, e.g. Texas Hold'em
TexasHoldemController.sol A minimized implementation of Texas Hold'em using OneTimeDrawInstance