Struct otpshka::HOTP

pub struct HOTP { /* fields omitted */ }

HMAC based OTP algorithm that uses simple counter as input.

Implementations

impl HOTP

pub fn new<T: AsRef<[u8]>>(algorithm: Algorithm, secret: T) -> Self

Initializes algorithm using provided algorithm and secret

• algorithm - Generally acceptable are HMAC based on sha-1, sha-256 and sha-512
• secret - Raw bytes used to derive HMAC key. User is responsible to decode it before passing.

pub fn sign(&self, counter: u64) -> impl AsRef<[u8]> + Clone + Copy

Signs provided counter value using stored HMAC key.

pub fn generate_num(&self, counter: u64, digits: u8) -> u32

Generates password as number from provided counter value with length of digits.

Note that in this case you must handle missing padding yourself.

pub fn generate_to<T: AsMut<[u8]>>(&self, counter: u64, dest: T)

Generates password based on provided counter value and writes it into provided dest.

This always writes dest.as_ref().len().

Recommended buffer length is be within 6..8

pub fn verify(&self, token: &str, counter: u64) -> bool

Checks whether provided token corresponds to counter.