EncryptMultipleValues

Category: Basic | Difficulty: Beginner | Chapters: Encryption | Concept: Store multiple encrypted values with a single proof

Store multiple encrypted values in one transaction.

Why this example

This example focuses on Store multiple encrypted values with a single proof. It is designed to be self-contained and easy to run locally.

Quick start

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

Dependencies

None

Contract and test

EncryptMultipleValues.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 EncryptMultipleValues
 * @author Gustavo Valverde
 * @notice Store multiple encrypted values in one transaction.
 * @dev Example for fhEVM Examples - Basic Category
 *
 * @custom:category basic
 * @custom:chapter encryption
 * @custom:concept Store multiple encrypted values with a single proof
 * @custom:difficulty beginner
 */
contract EncryptMultipleValues is ZamaEthereumConfig {
    mapping(address user => euint64 first) private firstValues;
    mapping(address user => euint64 second) private secondValues;

    /// @notice Store two encrypted values for the sender.
    /// @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 {
        euint64 first = FHE.fromExternal(encFirst, inputProof);
        euint64 second = FHE.fromExternal(encSecond, inputProof);

        firstValues[msg.sender] = first;
        secondValues[msg.sender] = second;

        FHE.allowThis(first);
        FHE.allowThis(second);
        FHE.allow(first, msg.sender);
        FHE.allow(second, msg.sender);
    }

    /// @notice Retrieve both encrypted values for a user.
    /// @param user Account holding the encrypted values
    /// @return First encrypted value
    /// @return Second encrypted value
    function getValues(address user) external view returns (euint64, euint64) {
        return (firstValues[user], secondValues[user]);
    }
}

EncryptMultipleValues.test.ts

Pitfalls to avoid

No pitfalls are highlighted in the tests for this example.

API Reference

Overview

Store multiple encrypted values in one transaction.

Developer Notes

Example for fhEVM Examples - Basic Category

storeValues

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

Store two encrypted values for the sender.

Parameters

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

getValues

function getValues(address user) external view returns (euint64, euint64)

Retrieve both encrypted values for a user.

Parameters

Name	Type	Description
user	address	Account holding the encrypted values

Return Values

Name	Type	Description
[0]	euint64	First encrypted value
[1]	euint64	Second encrypted value