Re: MessageDigest Length

From	"Robert Kochem" <robert.kochem@THRWHITE.remove-dii-this>
Subject	Re: MessageDigest Length
Message-ID	<f7k1llped7o1.13us8sed7f2um$.dlg@40tude.net> (permalink)
Newsgroups	comp.lang.java.security
References	<dcaa8c53-2b2d-4495-83f6-81e3442f4d8f@i29g2000prf.googlegroups.com>
Date	2011-04-27 16:07 +0000
Organization	TDS.net

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  To: comp.lang.java.security
sean@onset.com.au schrieb:

> Does anyone know if there is a way of setting the length of the hashed
> value returned from a message digest?

Sorry, but this does not make sense to me. Each digest algorithm has a
specified output length, e.g. MD5 128-Bit, SHA-1 160bit ...
Truncating this output may result in collisions and extending the output is
also not destined.

If you want a deterministic variable length output generated by a given
input you should look for a PRNG (Pseudo Random Number Generator) using
it's seed as input value.

Robert

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MessageDigest Length "sean" <sean@THRWHITE.remove-dii-this> - 2011-04-27 16:07 +0000
  Re: MessageDigest Length "Robert Kochem" <robert.kochem@THRWHITE.remove-dii-this> - 2011-04-27 16:07 +0000
    Re: MessageDigest Length "Roedy Green" <roedy.green@THRWHITE.remove-dii-this> - 2011-04-27 16:07 +0000
  Re: MessageDigest Length "Roedy Green" <roedy.green@THRWHITE.remove-dii-this> - 2011-04-27 16:07 +0000
  Re: MessageDigest Length "Maarten Bodewes" <maarten.bodewes@THRWHITE.remove-dii-this> - 2011-04-27 16:08 +0000
    Re: MessageDigest Length "Roedy Green" <roedy.green@THRWHITE.remove-dii-this> - 2011-04-27 16:08 +0000
      Re: MessageDigest Length "Maarten Bodewes" <maarten.bodewes@THRWHITE.remove-dii-this> - 2011-04-27 16:08 +0000
        Re: MessageDigest Length "Roedy Green" <roedy.green@THRWHITE.remove-dii-this> - 2011-04-27 16:08 +0000
        Re: MessageDigest Length "Roedy Green" <roedy.green@THRWHITE.remove-dii-this> - 2011-04-27 16:08 +0000
        Re: MessageDigest Length "rmoldskr+usenet" <rmoldskr+usenet@THRWHITE.remove-dii-this> - 2011-04-27 16:08 +0000

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