Re: [openpgp] [RFC4880bis PATCH] WIP: bind wire format representations to specific pubkey algorithms

Florian Weimer <fw@deneb.enyo.de> Sat, 05 June 2021 16:03 UTC

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From: Florian Weimer <fw@deneb.enyo.de>
To: Daniel Kahn Gillmor <dkg@fifthhorseman.net>
Cc: IETF OpenPGP WG <openpgp@ietf.org>
References: <20210602230847.3593022-1-dkg@fifthhorseman.net>
Date: Sat, 05 Jun 2021 18:03:14 +0200
In-Reply-To: <20210602230847.3593022-1-dkg@fifthhorseman.net> (Daniel Kahn Gillmor's message of "Wed, 2 Jun 2021 19:08:47 -0400")
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Subject: Re: [openpgp] [RFC4880bis PATCH] WIP: bind wire format representations to specific pubkey algorithms
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* Daniel Kahn Gillmor:

> The OpenPGP standard is in a bit of a mess when it comes to wire
> formats for public key algorithms.
>
> There are not infrequent reports of interoperability problems (most
> recently https://dev.gnupg.org/T5464), and difficulties for
> implementers in understanding what is expected.

I think this issue also affects RSA data because the way OpenPGP
specifies the operations, they are octet strings of a specific length,
not integers, and may including leading zero bytes.