Re: [9fans] In case anyone worries about block hash collision in venti

[erik quanstrom <quanstro@quanstro.net>]

> Sorry, this is all bunk.  You shouldn't be worried about
> an accidental collision.  You should be worried about
> an intentional collision.  Especially if your filesystem
> stores data that is under the attackers control such as
> email messages, web page caches, etc.  So what you need
> to analyze isn't how often an accidental collision happens
> but how hard it is to create an intentional collision.
> All the popular hash algorithms have been losing ground to
> attackers lately.

can you make this a little more concrete?  i'm having trouble
understanding how a email that an attacker controls is
a problem.  assuming the attacker can predict the headers
add well enough, this implies that the attacker, given access to
your venti, can retrieve an email said attacker sent.  where's
the problem?  i don't see it yet.

- erik