Adding a nounce before hashing as covert channel

[Werner Koch]

On Fri, 13 Dec 2024 12:43, andrewg said:

> would equally be possible to create a collision in an unsalted
> signature by manipulating the first N bits of the message. But while

But these first N bits of the message may allow to detect a
modification.  A non-deterministic salt allows to hide the modification.

I have not a problem with a _deterministic_ salt but I do have one with
adding a new covert channel.  And of course with the stupid way on how
this was added to the specs.  Extra data belongs into a signature
subpacket and if you really want it at the begin of the subpacket area,
well, specify it this way.

The whole point here is to willy-nilly make it impossible to support the
new signing packet.


Shalom-Salam,

   Werner


-- 
The pioneers of a warless world are the youth that
refuse military service.             - A. Einstein
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