ripemd128(n) RIPEMD Message-Digest Algorithm ripemd128(n) 







ripemd128 - RIPEMD-128 Message-Digest Algorithm








package require Tcl 8.2


package require ripemd128 ?1.0.3?


::ripemd::ripemd128 ?-hex? [ -channel channel
    | -file filename | string ]


::ripemd::hmac128 ?-hex? -key key [
    -channel channel | -file filename | string ]


::ripemd::RIPEMD128Init


::ripemd::RIPEMD128Update token data


::ripemd::RIPEMD128Final token


::ripemd::RIPEHMAC128Init key


::ripemd::RIPEHMAC128Update token data


::ripemd::RIPEHMAC128Final token












This package is an implementation in Tcl of the RIPEMD-128
    message-digest algorithm (1). This algorithm takes an arbitrary quantity of
    data and generates a 128-bit message digest from the input. The RIPEMD-128
    algorithm is based upon the MD4 algorithm (2, 4) but has been
    cryptographically strengthened against weaknesses that have been found in
    MD4 (4). RIPEMD-128 has been designed to be a drop-in replacement for MD4
    and MD5 (5). If security is the major consideration, then RIPEMD-160 or SHA1
    should be considered.


This package will use Trf to accelerate the digest
    computation if available. In the absence of an accelerator package the
    pure-Tcl implementation will be used.









  
::ripemd::ripemd128 ?-hex? [ -channel channel |
    -file filename | string ]

  
Calculate the RIPEMD-128 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 ripemd128 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::hmac128 ?-hex? -key key [ -channel
    channel | -file filename | string ]

  
Calculate an Hashed Message Authentication digest (HMAC) using the
      RIPEMD-128 digest algorithm. HMACs are described in RFC 2104 (6) and
      provide a RIPEMD-128 digest that includes a key. All options other than
      -key are as for the ::ripemd::ripemd128 command.










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 RIPEMD128Init to obtain a token and then call
    RIPEMD128Update as many times as required to add data to the hash. To
    release any resources and obtain the hash value, you then call
    RIPEMD128Final. An equivalent set of functions gives you a keyed
    digest (HMAC).


If you have critcl and have built the tcllibc
    package then the implementation of the hashing function will be performed by
    compiled code. Alternatively if both the Trf and Memchan extensions are
    available then these will be used. Finally the package will revert to a
    pure-Tcl implementation. The programming interface remains the same,
    however.



  
::ripemd::RIPEMD128Init

  
Begins a new RIPEMD-128 hash. Returns a token ID that must be used for the
      remaining functions.

  
::ripemd::RIPEMD128Update token data

  
Add data to the hash identified by token. Calling RIPEMD128Update
      $token "abcd" is equivalent to calling RIPEMD128Update
      $token "ab" followed by RIPEMD128Update $token
      "cb". See EXAMPLES.

  
::ripemd::RIPEMD128Final 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 128 bit RIPEMD-128 digest value.

  
::ripemd::RIPEHMAC128Init key

  
This is equivalent to the ::ripemd::RIPEMD128Init command except
      that it requires the key that will be included in the HMAC.

  
::ripemd::RIPEHMAC128Update token data

  

  
::ripemd::RIPEHMAC128Final token

  
These commands are identical to the RIPEMD128 equivalent commands.










% ripemd::ripemd128 -hex "Tcl does RIPEMD-128"
3cab177bae65205d81e7978f63556c63



% ripemd::hmac128 -hex -key Sekret "Tcl does RIPEMD-128"
b359dc5971a05beea0be7b106b30e389



% set tok [ripemd::RIPEMD128Init]
::ripemd::1
% ripemd::RIPEMD128Update $tok "Tcl "
% ripemd::RIPEMD128Update $tok "does "
% ripemd::RIPEMD128Update $tok "RIPEMD-128"
% ripemd::Hex [ripemd::RIPEMD128Final $tok]
3cab177bae65205d81e7978f63556c63










  
[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]

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

  
[6]

  
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)










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://sourceforge.net/tracker/?group_id=12883]. Please also report any
    ideas for enhancements you may have for either package and/or
  documentation.








md4, md5, ripemd160, sha1








RIPEMD, hashing, md4, message-digest, rfc 1320, rfc 1321, rfc
    2104, security








Hashes, checksums, and encryption








Copyright (c) 2004, Pat Thoyts <patthoyts@users.sourceforge.net>








  

    1.0.3
    ripemd