randomness-solidity

This repository contains the Solidity-based smart contracts library that facilitates Randamu's on-chain randomness requests.

By leveraging this library, smart contract developers can leverage on verifiable randomness on-chain that is tamper-proof and bias resistant.

This library is designed with modularity and simplicity in mind, allowing developers to extend and integrate it into their existing projects easily.

Smart Contract Addresses

Contract	Address	Network
SignatureSender Proxy	0x1c86A81D3CDD897aFdcA62a9b7219a39Aef7910B	Filecoin Calibration Testnet
SignatureSender Implementation	0x1790de5a9fBA748DCAf05e3a1755Cf1DD6b9B0F8	Filecoin Calibration Testnet
RandomnessSender Proxy	0x9c789bc7F2B5c6619Be1572A39F2C3d6f33001dC	Filecoin Calibration Testnet
RandomnessSender Implementation	0xF684f13850932bC7B51bd6bFF9236FB19E55F2B1	Filecoin Calibration Testnet
SignatureSchemeAddressProvider	0xD2b5084E68230D609AEaAe5E4cF7df9ebDd6375A	Filecoin Calibration Testnet
MockBN254SignatureScheme	0xE5aedc08Cf2B5650Cd84CE6DcaDC3763bAa8770B	Filecoin Calibration Testnet
MockRandomnessReceiver	0x6e7B9Ccb146f6547172E5cef237BBc222EC4D676	Filecoin Calibration Testnet

Using the Solidity Interfaces

Installation

Hardhat (npm)

$ npm install randomness-solidity

Foundry

$ forge install randa-mu/randomness-solidity

Importing

To use this library in your project, import the required files into your contract and use the proxy contract address for RandomnessSender in the constructor as the randomnessSender address parameter:

// Import the abstract RandomnessReceiverBase contract for creating randomness requests and handling randomness callbacks
import {RandomnessReceiverBase} from "../RandomnessReceiverBase.sol";

Example Usage

// SPDX-License-Identifier: MIT
pragma solidity 0.8.24;

import {RandomnessReceiverBase} from "../RandomnessReceiverBase.sol";

contract MockRandomnessReceiver is RandomnessReceiverBase {
    bytes32 public randomness;
    uint256 public requestId;

    constructor(address randomnessSender) RandomnessReceiverBase(randomnessSender) {}

    /**
     * @dev Requests randomness.
     *
     * This function calls the `requestRandomness` method to request a random value.
     * The `requestId` is updated with the ID returned from the randomness request.
     */
    function rollDice() external {
        requestId = requestRandomness();
    }

    /**
     * @dev Callback function that is called when randomness is received.
     * @param requestID The ID of the randomness request that was made.
     * @param _randomness The random value received.
     *
     * This function verifies that the received `requestID` matches the one that
     * was previously stored. If they match, it updates the `randomness` state variable
     * with the newly received random value.
     *
     * Reverts if the `requestID` does not match the stored `requestId`, ensuring that
     * the randomness is received in response to a valid request.
     */
    function onRandomnessReceived(uint256 requestID, bytes32 _randomness) internal override {
        require(requestId == requestID, "Request ID mismatch");
        randomness = _randomness;
    }
}

How It Works

• Randomness Request: The requestRandomness function allows the receiver smart contract to request randomness via the RandomnessSender contract.
• Callback Handling: The inherited onRandomnessReceived function allows the smart contract developer implement custom logic to handle the received randomness from Randamu's threshold network.

Licensing

This library is licensed under the MIT License which can be accessed here.

Contributing

Contributions are welcome! If you find a bug, have a feature request, or want to improve the code, feel free to open an issue or submit a pull request.