totp_embed

This is a fork of original totp-lite with some changes on API and added support for no_std.

fn totp1_tests() {
    let secret: &[u8] = b"12345678901234567890";
    assert_eq!(20, secret.len());
    let pairs = vec![
        (94287082, 59),
        (07081804, 1111111109),
        (14050471, 1111111111),
        (89005924, 1234567890),
        (69279037, 2000000000),
        (65353130, 20000000000),
    ];
    
    pairs.into_iter().for_each(|(expected, time)| {
        assert_eq!(expected, totp::<Sha1>(secret, time));
    });
}

See totp-lite for more details.

License: MIT

lib.rs:

A simple, correct TOTP library.

Time-based One-time Passwords are a useful way to authenticate a client, since a valid password expires long before it could ever be guessed by an attacker. This library provides an implementation of TOTP that matches its specification RFC6238, along with a simple interface.

Usage

The totp function is likely what you need. It uses the default time step of 30 seconds and produces 8 digits of output:

use std::time::{SystemTime, UNIX_EPOCH};
use totp_embed::{totp, Sha512};

// Negotiated between you and the authenticating service.
let password: &[u8] = b"secret";

// The number of seconds since the Unix Epoch.
let seconds: u64 = SystemTime::now().duration_since(UNIX_EPOCH).unwrap().as_secs();

// Specify the desired Hash algorithm via a type parameter.
// `Sha1` and `Sha256` are also available.
let result: u64 = totp::<Sha512>(password, seconds);

For full control over how the algorithm is configured, consider totp_custom.

Resources

• RFC6238: TOTP
• RFC6238 Errata