Re: NIST publishes new DSA draft

[[e-mail] ("Hal Finney")]

James Couzens writes:
> I had thought it a bit strange that someone writing so comprehensively
> about something related to digital signatures and to then make the
> statement as you did at the end of the paragraph I quoted.  Did you have
> some other intended meaning, such as broken by draft explicit
> prohibition or otherwise declared deprecated in a future draft?

Yes, sorry, my language was not as precise as it might have been.
I said we should be ready in case SHA-1 were broken, but as you note
it has been officially "broken" for over a year.  However that is just
a theoretical break and no actual examples of SHA-1 message collisions
have yet been published.  So at this point SHA-1 is in a bit of a limbo
state, theoretically broken but still in widespread use.

If the attack should get worse so that SHA-1 collisions could be found
in a practical amount of time, then we would have a much more urgent
need to switch to another hash.  That is what I really meant when I
said we should be ready if SHA-1 should be broken.

Hal Finney