ripemd160(3tcl) RIPEMD Message-Digest Algorithm ripemd160(3tcl)______________________________________________________________________________NAMEripemd160 - RIPEMD-160 Message-Digest Algorithm
SYNOPSIS
package require Tcl 8.2
package require ripemd160 ?1.0.3?
::ripemd::ripemd160 ?-hex? [ -channel channel | -file filename | string
]
::ripemd::hmac160 ?-hex? -key key [ -channel channel | -file filename |
string ]
::ripemd::RIPEMD160Init
::ripemd::RIPEMD160Update token data
::ripemd::RIPEMD160Final token
::ripemd::RIPEHMAC160Init key
::ripemd::RIPEHMAC160Update token data
::ripemd::RIPEHMAC160Final token
_________________________________________________________________DESCRIPTION
This package is an implementation in Tcl of the RIPEMD-160 message-
digest algorithm (1). This algorithm takes an arbitrary quantity of
data and generates a 160-bit message digest from the input. The
RIPEMD-160 algorithm is based upon the MD4 algorithm (2, 4) but has
been cryptographically strengthened against weaknesses that have been
found in MD4 (4).
This package will use cryptkit or Trf to accelerate the digest computa‐
tion if either package is available. In the absence of an accelerator
package the pure-Tcl implementation will be used.
COMMANDS
::ripemd::ripemd160 ?-hex? [ -channel channel | -file filename | string
]
Calculate the RIPEMD-160 digest of the data given in string.
This is returned as a binary string by default. Giving the -hex
option will return a hexadecimal encoded version of the digest.
The data to be hashed can be specified either as a string argu‐
ment to the ripemd160 command, or as a filename or a pre-opened
channel. If the -filename argument is given then the file is
opened, the data read and hashed and the file is closed. If the
-channel argument is given then data is read from the channel
until the end of file. The channel is not closed.
Only one of -file, -channel or string should be given.
::ripemd::hmac160 ?-hex? -key key [ -channel channel | -file filename |
string ]
Calculate an Hashed Message Authentication digest (HMAC) using
the RIPEMD-160 digest algorithm. HMACs are described in RFC 2104
(5) and provide a RIPEMD-160 digest that includes a key. All
options other than -key are as for the ::ripemd::ripemd160 com‐
mand.
PROGRAMMING INTERFACE
For the programmer, hash functions can be viewed as a bucket into which
one pours data. When you have finished, you extract a value that is
uniquely derived from the data that was poured into the bucket. The
programming interface to the hash operates on a token (equivalent to
the bucket). You call RIPEMD160Init to obtain a token and then call
RIPEMD160Update as many times as required to add data to the hash. To
release any resources and obtain the hash value, you then call
RIPEMD160Final. An equivalent set of functions gives you a keyed digest
(HMAC).
::ripemd::RIPEMD160Init
Begins a new RIPEMD-160 hash. Returns a token ID that must be
used for the remaining functions.
::ripemd::RIPEMD160Update token data
Add data to the hash identified by token. Calling
RIPEMD160Update $token "abcd" is equivalent to calling
RIPEMD160Update $token "ab" followed by RIPEMD160Update $token
"cb". See EXAMPLES.
::ripemd::RIPEMD160Final token
Returns the hash value and releases any resources held by this
token. Once this command completes the token will be invalid.
The result is a binary string of 16 bytes representing the 160
bit RIPEMD-160 digest value.
::ripemd::RIPEHMAC160Init key
This is equivalent to the ::ripemd::RIPEMD160Init command except
that it requires the key that will be included in the HMAC.
::ripemd::RIPEHMAC160Update token data
::ripemd::RIPEHMAC160Final token
These commands are identical to the RIPEMD160 equivalent com‐
mands.
EXAMPLES
% ripemd::ripemd160 -hex "Tcl does RIPEMD-160"
0829dea75a1a7074c702896723fe37763481a0a7
% ripemd::hmac160 -hex -key Sekret "Tcl does RIPEMD-160"
bf0c927231733686731dddb470b64a9c23f7f53b
% set tok [ripemd::RIPEMD160Init]
::ripemd::1
% ripemd::RIPEMD160Update $tok "Tcl "
% ripemd::RIPEMD160Update $tok "does "
% ripemd::RIPEMD160Update $tok "RIPEMD-160"
% ripemd::Hex [ripemd::RIPEMD160Final $tok]
0829dea75a1a7074c702896723fe37763481a0a7
REFERENCES
[1] H. Dobbertin, A. Bosselaers, B. Preneel, "RIPEMD-160, a
strengthened version of RIPEMD" http://www.esat.kuleu‐
ven.ac.be/~cosicart/pdf/AB-9601/AB-9601.pdf
[2] Rivest, R., "The MD4 Message Digest Algorithm", RFC 1320, MIT,
April 1992. (http://www.rfc-editor.org/rfc/rfc1320.txt)
[3] Rivest, R., "The MD4 message digest algorithm", in A.J. Menezes
and S.A. Vanstone, editors, Advances in Cryptology - CRYPTO '90
Proceedings, pages 303-311, Springer-Verlag, 1991.
[4] Dobbertin, H., "Cryptanalysis of MD4", Journal of Cryptology vol
11 (4), pp. 253-271 (1998)
[5] Krawczyk, H., Bellare, M. and Canetti, R. "HMAC: Keyed-Hashing
for Message Authentication", RFC 2104, February 1997.
(http://www.rfc-editor.org/rfc/rfc2104.txt)
BUGS, IDEAS, FEEDBACK
This document, and the package it describes, will undoubtedly contain
bugs and other problems. Please report such in the category ripemd of
the Tcllib SF Trackers [http://source‐
forge.net/tracker/?group_id=12883]. Please also report any ideas for
enhancements you may have for either package and/or documentation.
SEE ALSO
md4, md5, ripemd128, sha1
KEYWORDS
RIPEMD, hashing, md4, message-digest, rfc 1320, rfc 1321, rfc 2104,
security
CATEGORY
Hashes, checksums, and encryption
COPYRIGHT
Copyright (c) 2004, Pat Thoyts <patthoyts@users.sourceforge.net>
ripemd 1.0.3 ripemd160(3tcl)
