[tahoe-dev] [tahoe-lafs] #217: DSA-based mutable files -- small URLs, fast file creation

[tahoe-lafs]

#217: DSA-based mutable files -- small URLs, fast file creation
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 Reporter:  zooko           |           Owner:  zooko     
     Type:  enhancement     |          Status:  assigned  
 Priority:  major           |       Milestone:  eventually
Component:  code-mutable    |         Version:  0.7.0     
 Keywords:  mutable crypto  |   Launchpad_bug:            
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Comment(by swillden):

 Replying to [comment:45 zooko]:
 > That completely solves the weakness that you've identified, right Shawn?

 I may be missing something, but I don't think it does.

 The issue I referred to has to do not with the generation of y, but of the
 multiplication of x by y (mod q), and the subsequent use of xy as the
 signing key.  The problem is that the distribution of xy mod q values is
 not uniform.

 I should mention that it's been years since I studied ECDSA and I don't at
 present understand anything about how the signing key xy is used to
 perform a signing operation.  I'm just noting that your method for
 constructing the signing key results in some signing keys being more
 likely than others.

-- 
Ticket URL: <http://allmydata.org/trac/tahoe/ticket/217#comment:46>
tahoe-lafs <http://allmydata.org>
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