Re: [CFRG] RSA PSS Salt Length for HTTP Message Signatures

"Salz, Rich" <rsalz@akamai.com> Fri, 28 May 2021 21:23 UTC

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From: "Salz, Rich" <rsalz@akamai.com>
To: Justin Richer <jricher@mit.edu>
CC: Benjamin Kaduk <kaduk@mit.edu>, Brian Smith <brian@briansmith.org>, "IRTF CFRG" <cfrg@irtf.org>, Russ Housley <housley@vigilsec.com>
Thread-Topic: [CFRG] RSA PSS Salt Length for HTTP Message Signatures
Thread-Index: AQHXUnAvqLkAEgqnB0OGVKflJ0MxYKr2neCAgAGtcgCAAAJXAIAAonEAgABetoCAACx0AA==
Date: Fri, 28 May 2021 21:23:24 +0000
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References: <1EED8807-C5C5-461F-BE60-34C44791849E@mit.edu> <1BF68544-CB14-4A60-88BB-4E80E2D9A094@vigilsec.com> <CAFewVt54d6NGEYOX6Tx=gMf+p9NqTVkb9VkRxr+VZL5eDSmhmA@mail.gmail.com> <20210527232354.GY32395@kduck.mit.edu> <67015DB5-A45F-41C7-A236-C54DEB30DD8F@akamai.com> <EB0D5FEF-C96A-4206-95C5-A2AD9C6A7193@mit.edu>
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Subject: Re: [CFRG] RSA PSS Salt Length for HTTP Message Signatures
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> but something to note: We aren’t :just: defining RSA-PSS, we’re also defining a flavor of RSA 1.5, a flavor of HMAC, and a flavor of ECDSA, each with fixed parameters including sizes and curves and the like. Which means that our own version of PSS is going to be a very strict and narrow selection tied to a single identifier, and if there’s enough of a draw from any community to define another set of parameters, it can be registered with a new label. 

That makes a great deal of sense, and mitigates/removes the concerns in the link I posted.

Nice work.