YubiServe is a lightweight Validation Server supporting both OATH/HOTP
and Yubico Yubikey implementations, written in Python that uses an
SQLite database or, optionally, a MySQL database. It has an integrated
threaded webserver, with HTTPS/SSL support, compatible with the
Yubico validation protocol 2.0 including HMAC SHA-1 signatures to
provide for authentication of the server.