dynalogin is a distributed two-factor authentication suite that combines a secure UNIX server and API with an Android soft token. Open standards (HOTP, TOTP, and soon OCRA) are used for one-time passwords. A C library is provided for inclusion in existing software and Web sites. OpenID (using SimpleID) is supported for Web applications and single sign on. PAM is supported for easy UNIX and LDAP integration (SASL, RADIUS, and JAAS in development). It works with Google Authenticator or the dynalogin Android application.
pam_supair is a PAM module for use with su(1) that authenticates the user if and only if that user's name (obtained via that user's real id) and su's target user name (obtained via pam_get_user(3)) form a pair that is allowed by the configuration. Multiple pairs can be specified.
The HOTP Toolkit package contains tools that are useful when deploying the one-time password HOTP technology. It contains a shared library, a command-line tool to generate and validate one-time passwords, and a PAM module (pam_hotp) to make system login or SSH use HOTP one-time passwords for authentication.