Struct libreauth::oath::HOTP

pub struct HOTP { /* fields omitted */ }

Generates, manipulates and checks HOTP codes.

Methods

impl HOTP

pub fn generate(&self) -> String

Generate the HOTP value.

Examples

let key_ascii = "12345678901234567890".to_owned();
let mut hotp = libreauth::oath::HOTPBuilder::new()
    .ascii_key(&key_ascii)
    .finalize()
    .unwrap();

let code = hotp.generate();
assert_eq!(code, "755224");
let code = hotp.increment_counter().generate();
assert_eq!(code, "287082");

pub fn increment_counter(&mut self) -> &mut HOTP

Increments the internal counter.

pub fn is_valid(&self, code: &str) -> bool

Checks if the given code is valid. This implementation uses the double HMAC verification in order to prevent a timing side channel attack.

Examples

let key_ascii = "12345678901234567890".to_owned();
let user_code = "755224".to_owned();
let valid = libreauth::oath::HOTPBuilder::new()
    .ascii_key(&key_ascii)
    .finalize()
    .unwrap()
    .is_valid(&user_code);
assert!(valid);

pub fn key_uri_format<'a>(
    &'a self,
    issuer: &'a str,
    account_name: &'a str
) -> KeyUriBuilder<'a>

Creates the Key Uri Format according to the Google authenticator specification. This value can be used to generete QR codes which allow easy scanning by the end user. The returned KeyUriBuilder allows for additional customizations.

WARNING: The finalized value contains the secret key of the authentication process and should only be displayed to the corresponding user!

Example

let key_ascii = "12345678901234567890".to_owned();
let mut hotp = libreauth::oath::HOTPBuilder::new()
    .ascii_key(&key_ascii)
    .finalize()
    .unwrap();

let uri = hotp
    .key_uri_format("Provider1", "alice@example.com")
    .finalize();

assert_eq!(
    uri,
    "otpauth://hotp/Provider1:alice@example.com?secret=GEZDGNBVGY3TQOJQGEZDGNBVGY3TQOJQ&issuer=Provider1&counter=0"
);