[TLS] Re: Composite ML-DSA

Hal Murray <halmurray+tls@sonic.net> Sat, 18 April 2026 23:12 UTC

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To: Peter Gutmann <pgut001=40cs.auckland.ac.nz@dmarc.ietf.org>
From: Hal Murray <halmurray+tls@sonic.net>
In-Reply-To: Message from Peter Gutmann <pgut001=40cs.auckland.ac.nz@dmarc.ietf.org> of "Sat, 18 Apr 2026 15:52:13 -0000." <MEAPR01MB3654FFF6F710C76C95313D81EE212@MEAPR01MB3654.ausprd01.prod.outlook.com>
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Subject: [TLS] Re: Composite ML-DSA
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Peter Gutmann said:
> Calling Apples and Oranges one thing just because you add the word
> "composite" in front and define an OID for it doesn't make them so,
> they're still two completely different things with separate keys,
> separate algorithms, separate implementations of the algorithms. 

Right.  But if you put the apple and orange in a box, then you only need 
one shipping label.

Using a composite with a single OID means that the top level code doesn't 
need to change.  Things like here is the filename for the key(s) still 
work.  Yes, the implementation has to open the box.  40 lines of code to 
split the key into 2 parts and call the 2 implementations doesn't seem 
unreasonable.


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