Message-ID: <ab29dd6f-1301-e012-8898-9c739ca511a3@maciej.szmigiero.name>
Date:   Tue, 11 Jan 2022 21:33:15 +0100
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To:     Roberto Sassu <roberto.sassu@huawei.com>
Cc:     keyrings@vger.kernel.org, linux-crypto@vger.kernel.org,
        linux-integrity@vger.kernel.org, linux-fscrypt@vger.kernel.org,
        linux-kernel@vger.kernel.org, zohar@linux.ibm.com,
        ebiggers@kernel.org, dhowells@redhat.com, dwmw2@infradead.org,
        herbert@gondor.apana.org.au, davem@davemloft.net
References: <20220111180318.591029-1-roberto.sassu@huawei.com>
From:   "Maciej S. Szmigiero" <mail@maciej.szmigiero.name>
Subject: Re: [PATCH 00/14] KEYS: Add support for PGP keys and signatures
In-Reply-To: <20220111180318.591029-1-roberto.sassu@huawei.com>
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On 11.01.2022 19:03, Roberto Sassu wrote:
> Support for PGP keys and signatures was proposed by David long time ago,
> before the decision of using PKCS#7 for kernel modules signatures
> verification was made. After that, there has been not enough interest to
> support PGP too.
> 
> Lately, when discussing a proposal of introducing fsverity signatures in
> Fedora [1], developers expressed their preference on not having a separate
> key for signing, which would complicate the management of the distribution.
> They would be more in favor of using the same PGP key, currently used for
> signing RPM headers, also for file-based signatures (not only fsverity, but
> also IMA ones).

Aren't PGP keys simply RSA / ECC / EdDSA keys with additional metadata?
Can't they be unwrapped from their (complex) PGP format in userspace and
loaded raw into the kernel, in a similar way as they are sometimes used
for SSH authentication?

This will save us from having to add complex parsers (a well-known source
of bugs) into the kernel - I guess there aren't any plans to add an
in-kernel PGP Web of Trust implementation.

Thanks,
Maciej