The OATH Toolkit provide components for building one-time password
authentication systems. It contains shared libraries, command line tools and a
PAM module. Supported technologies include the event-based HOTP algorithm
(RFC4226) and the time-based TOTP algorithm (RFC6238). OATH stands for Open
AuTHentication, which is the organization that specify the algorithms. For
managing secret key files, the Portable Symmetric Key Container (PSKC) format
described in RFC6030 is supported.