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Message-ID: <b1f3b34ec40b86fe74c128cdcd549a294da122f7.camel@kernel.org>
Subject: Re: [PATCH v4 12/13] tpm: add the null key name as a sysfs export
From:   Jarkko Sakkinen <jarkko@kernel.org>
To:     James Bottomley <James.Bottomley@HansenPartnership.com>,
        linux-integrity@vger.kernel.org
Cc:     keyrings@vger.kernel.org, Ard Biesheuvel <ardb@kernel.org>
Date:   Sun, 23 Apr 2023 08:38:30 +0300
In-Reply-To: <20230403214003.32093-13-James.Bottomley@HansenPartnership.com>
References: <20230403214003.32093-1-James.Bottomley@HansenPartnership.com>
         <20230403214003.32093-13-James.Bottomley@HansenPartnership.com>
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On Mon, 2023-04-03 at 17:40 -0400, James Bottomley wrote:
> This is the last component of encrypted tpm2 session handling that
> allows us to verify from userspace that the key derived from the NULL
> seed genuinely belongs to the TPM and has not been spoofed.

How would you do this in practice with the help of this file?

The current description does not make a case to have this file, unless
it is supported by an usage example to do what you claim above.

BR, Jarkko