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

Peter Gutmann <pgut001@cs.auckland.ac.nz> Sat, 29 May 2021 09:22 UTC

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From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: Neil Madden <neil.e.madden@gmail.com>
CC: Justin Richer <jricher@mit.edu>, IRTF CFRG <Cfrg@irtf.org>
Thread-Topic: [CFRG] RSA PSS Salt Length for HTTP Message Signatures
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Date: Sat, 29 May 2021 09:21:54 +0000
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Archived-At: <https://mailarchive.ietf.org/arch/msg/cfrg/d7stivLpDI1tji_nahb5ucqt31g>
Subject: Re: [CFRG] RSA PSS Salt Length for HTTP Message Signatures
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Neil Madden <neil.e.madden@gmail.com> writes:

>By this do you mean *constant-time* memcmp? Otherwise that seems something
>quite easy to get wrong.

You're doing a memcmp() on known, public data, there's nothing to leak so no
need for a constant-time memcmp().

Peter.

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