Quick start

This document explains the basic steps of using the high-level API of TFHE-rs.

Workflow explanation

These are the steps to use the TFHE-rs high-level API:

1. Import the TFHE-rs prelude

2. Client-side: configure and generate keys

3. Client-side: encrypt data

4. Server-side: set the server key

5. Server-side: compute over encrypted data

6. Client-side: decrypt data

This example demonstrates the basic workflow combining the client and server parts:

use tfhe::{ConfigBuilder, generate_keys, set_server_key, FheUint8};
use tfhe::prelude::*;

fn main() {
    let config = ConfigBuilder::default().build();

    // Client-side
    let (client_key, server_key) = generate_keys(config);

    let clear_a = 27u8;
    let clear_b = 128u8;

    let a = FheUint8::encrypt(clear_a, &client_key);
    let b = FheUint8::encrypt(clear_b, &client_key);

    //Server-side
    set_server_key(server_key);
    let result = a + b;

    //Client-side
    let decrypted_result: u8 = result.decrypt(&client_key);

    let clear_result = clear_a + clear_b;

    assert_eq!(decrypted_result, clear_result);
}

The default configuration for x86 Unix machines is as follows:

tfhe = { version = "0.7.2", features = ["integer", "x86_64-unix"]}

Refer to the installation documentation for configuration options of different platforms.Learn more about homomorphic types features in the configuration documentation.

Step1: Importing

TFHE-rs uses traits to implement consistent APIs and generic functions. To use traits, they must be in scope.

The prelude pattern provides a convenient way to globally import all important TFHE-rs traits at once. This approach saves time and avoids confusion.

use tfhe::prelude::*;