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On Tue, Jul 22, 2003 at 11:42:26PM -0700, Fred Van Andel wrote: |
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> As for the security of MD5, there is no published instance of anyone |
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> finding 2 different datasets that produce an identical hash value. MD5 |
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> is a 128 bit hash algorithm so in theory it would be be required to |
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> calculate approximately 1.2 * sqrt(2^128) different hashes in order to |
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> have a 50% chance of a single collision. That would require > 350 |
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> billion gigabytes just to store the hashes. I believe MD5 to be secure |
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> enough for this application. |
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I'd be VERY careful with this. |
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http://www.rsasecurity.com/rsalabs/faq/3-6-6.html |
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I've seen much more recent research into it myself, along with a way of |
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making it SIGNIFICENTLY more difficult to break. |
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|
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Namely, store the correct filesize along with the MD5 sum in a |
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verifiable fashion. Having file containing a list of tarballs and their |
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sizes, then providing a GPG signature for that file makes solves the |
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issue to a level such that even all the computers in the world in 10 |
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years could not beat it [famous last words, after seeing the |
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crypto-attack on RSA keys using a massive NFS setup]. |
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-- |
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Robin Hugh Johnson |
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E-Mail : robbat2@××××××××××××××.net |
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Home Page : http://www.orbis-terrarum.net/?l=people.robbat2 |
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ICQ# : 30269588 or 41961639 |
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GnuPG FP : 11AC BA4F 4778 E3F6 E4ED F38E B27B 944E 3488 4E85 |
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