Erlang implementation of the HOTP algoritm (RFC-4226)
The RFC-4226 describes HOTP:
An HMAC-Based One-Time Password Algoritm
ehotp implements the algorithm described in the RFC-4226 plus a supporting framework for building an authentication system based on One-Time Passwords (OTPs).
The basic idea is to authenticate a user with a personal PIN code + an OTP that the user has generated.
Clone it and run: make.
erl -pa ./ebin -s ehotp