otp(n)							RFC 2289 A One-Time Password System						    otp(n)

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NAME

       otp - One-Time Passwords

SYNOPSIS

       package require Tcl  8.2

       package require otp  ?1.0.0?

       ::otp::otp-md4 ?-hex? ?-words? -seed seed -count count data

       ::otp::otp-md5 ?-hex? ?-words? -seed seed -count count data

       ::otp::otp-sha1 ?-hex? ?-words? -seed seed -count count data

       ::otp::otp-rmd160 ?-hex? ?-words? -seed seed -count count data

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DESCRIPTION

       This  package  is  an  implementation  in Tcl of the One-Time Password system as described in RFC 2289 (1). This system uses message-digest
       algorithms to sequentially hash a passphrase to create single-use passwords. The resulting data is then provided  to  the  user	as  either
       hexadecimal  digits  or encoded using a dictionary of 2048 words. This system is used by OpenBSD for secure login and can be used as a SASL
       mechanism for authenticating users.

       In this implementation we provide support for four algorithms that are included in the tcllib distribution: MD5 (2),  MD4  (3),	RIPE-MD160
       (4) and SHA-1 (5).

COMMANDS

       ::otp::otp-md4 ?-hex? ?-words? -seed seed -count count data

       ::otp::otp-md5 ?-hex? ?-words? -seed seed -count count data

       ::otp::otp-sha1 ?-hex? ?-words? -seed seed -count count data

       ::otp::otp-rmd160 ?-hex? ?-words? -seed seed -count count data

EXAMPLES

       % otp::otp-md5 -count 99 -seed host67821 "My Secret Pass Phrase"
       (binary gibberish)
       % otp::otp-md5 -words -count 99 -seed host67821 "My Secret Pass Phrase"
       SOON ARAB BURG LIMB FILE WAD
       % otp::otp-md5 -hex -count 99 -seed host67821 "My Secret Pass Phrase"
       e249b58257c80087

REFERENCES

       [1]    Haller, N. et al., "A One-Time Password System", RFC 2289, February 1998.  http://www.rfc-editor.org/rfc/rfc2289.txt

       [2]    Rivest,  R.,  "The  MD5  Message-Digest  Algorithm",  RFC  1321,	MIT  and RSA Data Security, Inc, April 1992.  (http://www.rfc-edi-
	      tor.org/rfc/rfc1321.txt)

       [3]    Rivest, R., "The MD4 Message Digest Algorithm", RFC 1320, MIT, April 1992. (http://www.rfc-editor.org/rfc/rfc1320.txt)

       [4]    H. Dobbertin, A. Bosselaers, B. Preneel,	"RIPEMD-160,  a  strengthened  version	of  RIPEMD"  http://www.esat.kuleuven.ac.be/~cosi-
	      cart/pdf/AB-9601/AB-9601.pdf

       [5]    "Secure	Hash   Standard",   National   Institute   of	Standards  and	Technology,  U.S.  Department  Of  Commerce,  April  1995.
	      (http://www.itl.nist.gov/fipspubs/fip180-1.htm)

BUGS, IDEAS, FEEDBACK
       This document, and the package it describes, will undoubtedly contain bugs and other problems.  Please report such in the category  otp	of
       the  Tcllib  SF	Trackers [http://sourceforge.net/tracker/?group_id=12883].  Please also report any ideas for enhancements you may have for
       either package and/or documentation.

SEE ALSO

       SASL, md4, md5, ripemd160, sha1

KEYWORDS

       hashing, message-digest, password, rfc 2289, security

CATEGORY

       Hashes, checksums, and encryption

COPYRIGHT

       Copyright (c) 2006, Pat Thoyts <patthoyts@users.sourceforge.net>

otp								       1.0.0								    otp(n)