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The OATH Toolkit contains a shared library, command line tool and a PAM module that makes it possible to build one-time password authentication systems
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latest commit e48acdb8a9
Simon Josefsson jas4711 authored


Copyright (C) 2009-2011 Simon Josefsson.  Licensed under the GPLv3+.

The OATH Toolkit makes it easy to build one-time password
authentication systems.  It contains a shared library, a command line
tool 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.

The components included in the package is:

  * liboath: A shared and static C library for OATH handling.

  * oathtool: A command line tool for generating and validating OTPs.

  * pam_oath: A PAM module for pluggable login authentication for OATH.

See each sub-directory for more information.

For updates on the project please visit our web page:

For e-mail discussions related the OATH Toolkit, please send e-mail to after subscribing to the mailing list
through this web page:

Note that the OATH Toolkit project used to be called "HOTP Toolkit",
and there are still references to the old project name.

For any copyright year range specified as YYYY-ZZZZ in this package
note that the range specifies every single year in that closed interval.
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