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Date: Wed, 24 Apr 2024 20:42:33 -0700
From: Eric Biggers <ebiggers@kernel.org>
To: Fan Wu <wufan@linux.microsoft.com>
Cc: corbet@lwn.net, zohar@linux.ibm.com, jmorris@namei.org,
	serge@hallyn.com, tytso@mit.edu, axboe@kernel.dk, agk@redhat.com,
	snitzer@kernel.org, eparis@redhat.com, paul@paul-moore.com,
	linux-doc@vger.kernel.org, linux-integrity@vger.kernel.org,
	linux-security-module@vger.kernel.org, fsverity@lists.linux.dev,
	linux-block@vger.kernel.org, dm-devel@lists.linux.dev,
	audit@vger.kernel.org, linux-kernel@vger.kernel.org,
	Deven Bowers <deven.desai@linux.microsoft.com>
Subject: Re: [PATCH v17 17/21] ipe: enable support for fs-verity as a trust
 provider
Message-ID: <20240425034233.GB1401@sol.localdomain>
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 <1712969764-31039-18-git-send-email-wufan@linux.microsoft.com>
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On Fri, Apr 12, 2024 at 05:56:00PM -0700, Fan Wu wrote:
> +config IPE_PROP_FS_VERITY
> +	bool "Enable property for fs-verity files"
> +	depends on FS_VERITY && FS_VERITY_BUILTIN_SIGNATURES
> +	help
> +	  This option enables the usage of properties "fsverity_signature"
> +	  and "fsverity_digest". These properties evaluate to TRUE when
> +	  a file is fsverity enabled and has a valid builtin signature
> +	  whose signing cert is in the .fs-verity keyring or its
> +	  digest matches the supplied value in the policy.
> +
> +	  if unsure, answer Y.

Does this really need to depend on FS_VERITY_BUILTIN_SIGNATURES?  That's needed
for fsverity_signature to work, but fsverity_digest would work without it.

I'd prefer if people had the option of only turning on
FS_VERITY_BUILTIN_SIGNATURES if they really need it.

- Eric