linux-kernel - Re: [PATCH v12 06/10] crypto: Add supplementary info param to asymmetric key signature verification

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <aXYmhZdVtvilYMHg@kernel.org>
Date: Sun, 25 Jan 2026 16:19:49 +0200
From: Jarkko Sakkinen <jarkko@...nel.org>
To: Eric Biggers <ebiggers@...nel.org>
Cc: David Howells <dhowells@...hat.com>, Lukas Wunner <lukas@...ner.de>,
	Ignat Korchagin <ignat@...udflare.com>,
	Herbert Xu <herbert@...dor.apana.org.au>,
	Luis Chamberlain <mcgrof@...nel.org>,
	Petr Pavlu <petr.pavlu@...e.com>,
	Daniel Gomez <da.gomez@...nel.org>,
	Sami Tolvanen <samitolvanen@...gle.com>,
	"Jason A . Donenfeld" <Jason@...c4.com>,
	Ard Biesheuvel <ardb@...nel.org>,
	Stephan Mueller <smueller@...onox.de>, linux-crypto@...r.kernel.org,
	keyrings@...r.kernel.org, linux-modules@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	"David S. Miller" <davem@...emloft.net>
Subject: Re: [PATCH v12 06/10] crypto: Add supplementary info param to
 asymmetric key signature verification

On Tue, Jan 20, 2026 at 02:03:21PM -0800, Eric Biggers wrote:
> On Thu, Jan 15, 2026 at 09:50:48PM +0000, David Howells wrote:
> > Add a supplementary information parameter to the asymmetric key signature
> > verification API, in particular crypto_sig_verify() and sig_alg::verify.
> > This takes the form of a printable string containing of key=val elements.
> 
> As I'm sure you're aware, C has native support for function parameters.
> No need to serialize to a string on the caller side and then deserialize
> in the callee.
> 
> This is yet another example of a case where trying to fit different
> algorithms into a generic API doesn't work well.
> 
> We should just have a library API for each signature algorithm, with
> each algorithm taking the parameters it needs.

This would be a great idea IMHO. I'm looking into renewing my TPM2
asymmetric keys patch set some day, and e.g., for that such primitives
would be more ergonomic fit.

> 
> - Eric

BR, Jarkko