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Date: Tue, 21 May 2024 09:36:00 +0300
Message-Id: <D1F44P3VLTBN.30LUQ60X5J3DN@kernel.org>
Subject: ASN.1
From: "Jarkko Sakkinen" <jarkko@kernel.org>
To: <rust-for-linux@vger.kernel.org>
X-Mailer: aerc 0.17.0

Hi,

There's one application where it would make a lot of sense to have the
core implementation in Rust, and make it callable from C. It is encoding
and decoding of ASN.1 (DER).

It is essentially hierarchical binary parsing, i.e. exactly kind of
stuff where it is too easy to shoot yourself into foot with C.

So question is how to approach this? How the holding data structure for
holding the deserialized data should represented so that is is also
directly accessible from C?

Maybe not the sexiest application ever, but it is an actual applications
where Rust might weight a lot, also for the C code base ;-)

I'm interested to help with this too as I consume a lot of DER type of
input data... so I know what it should look like to work at all for the
C code. Or do not know at this poinnt, but can verify the sensibility
at minimum :-)

BR, Jarkko