PublicDecryptMultipleValues

Category: Basic | Difficulty: Intermediate | Chapters: Decryption Public, Relayer | Concept: Public decryption flow for multiple encrypted values

Publish multiple encrypted results for public decryption.

Why this example

This example focuses on Public decryption flow for multiple encrypted values. It is designed to be self-contained and easy to run locally.

Quick start

npm install
npm run test:mocked -- test/basic/PublicDecryptMultipleValues.test.ts

Dependencies

None

Contract and test

PublicDecryptMultipleValues.sol

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.27;

import {FHE, euint64, externalEuint64} from "@fhevm/solidity/lib/FHE.sol";
import {ZamaEthereumConfig} from "@fhevm/solidity/config/ZamaConfig.sol";

/**
 * @title PublicDecryptMultipleValues
 * @author Gustavo Valverde
 * @notice Publish multiple encrypted results for public decryption.
 * @dev Example for fhEVM Examples - Basic Category
 *
 * @custom:category basic
 * @custom:chapter decryption-public, relayer
 * @custom:concept Public decryption flow for multiple encrypted values
 * @custom:difficulty intermediate
 */
contract PublicDecryptMultipleValues is ZamaEthereumConfig {
    euint64 private lastFirst;
    euint64 private lastSecond;

    /// @notice Store two encrypted values.
    /// @param encFirst First encrypted value handle
    /// @param encSecond Second encrypted value handle
    /// @param inputProof Proof for the encrypted inputs
    function storeValues(
        externalEuint64 encFirst,
        externalEuint64 encSecond,
        bytes calldata inputProof
    ) external {
        lastFirst = FHE.fromExternal(encFirst, inputProof);
        lastSecond = FHE.fromExternal(encSecond, inputProof);

        FHE.allowThis(lastFirst);
        FHE.allowThis(lastSecond);
        FHE.allow(lastFirst, msg.sender);
        FHE.allow(lastSecond, msg.sender);
    }

    /// @notice Publish both values for public decryption.
    function publishValues() external {
        FHE.makePubliclyDecryptable(lastFirst);
        FHE.makePubliclyDecryptable(lastSecond);
    }

    /// @notice Returns the handles for public decryption.
    /// @return Handle for the first encrypted value
    /// @return Handle for the second encrypted value
    function getValueHandles() external view returns (bytes32, bytes32) {
        return (FHE.toBytes32(lastFirst), FHE.toBytes32(lastSecond));
    }
}

PublicDecryptMultipleValues.test.ts

Pitfalls to avoid

No pitfalls are highlighted in the tests for this example.

API Reference

Overview

Publish multiple encrypted results for public decryption.

Developer Notes

Example for fhEVM Examples - Basic Category

storeValues

function storeValues(externalEuint64 encFirst, externalEuint64 encSecond, bytes inputProof) external

Store two encrypted values.

Parameters

Name	Type	Description
encFirst	externalEuint64	First encrypted value handle
encSecond	externalEuint64	Second encrypted value handle
inputProof	bytes	Proof for the encrypted inputs

publishValues

function publishValues() external

Publish both values for public decryption.

getValueHandles

function getValueHandles() external view returns (bytes32, bytes32)

Returns the handles for public decryption.

Return Values

Name	Type	Description
[0]	bytes32	Handle for the first encrypted value
[1]	bytes32	Handle for the second encrypted value