NAME¶
ripemd160 - 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
computation 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 argument 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 command.
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 commands.
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.kuleuven.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 Trackers [
http://core.tcl.tk/tcllib/reportlist]. 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>