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Date:   Wed, 18 May 2022 06:31:33 +0200
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Subject: Re: [PATCH v10 2/7] KEYS: trusted: allow use of kernel RNG for key
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To:     Mimi Zohar <zohar@linux.ibm.com>,
        "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc:     James Bottomley <jejb@linux.ibm.com>,
        Jarkko Sakkinen <jarkko@kernel.org>,
        David Howells <dhowells@redhat.com>, kernel@pengutronix.de,
        Sumit Garg <sumit.garg@linaro.org>,
        Pankaj Gupta <pankaj.gupta@nxp.com>,
        David Gstir <david@sigma-star.at>,
        Michael Walle <michael@walle.cc>,
        John Ernberg <john.ernberg@actia.se>,
        James Morris <jmorris@namei.org>,
        "Serge E. Hallyn" <serge@hallyn.com>,
        =?UTF-8?Q?Horia_Geant=c4=83?= <horia.geanta@nxp.com>,
        Herbert Xu <herbert@gondor.apana.org.au>,
        "David S. Miller" <davem@davemloft.net>,
        Jan Luebbe <j.luebbe@pengutronix.de>,
        Eric Biggers <ebiggers@kernel.org>,
        Richard Weinberger <richard@nod.at>,
        Franck LENORMAND <franck.lenormand@nxp.com>,
        Matthias Schiffer <matthias.schiffer@ew.tq-group.com>,
        keyrings@vger.kernel.org, linux-crypto@vger.kernel.org,
        linux-integrity@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-security-module@vger.kernel.org,
        Pascal Van Leeuwen <pvanleeuwen@verimatrix.com>
References: <20220513145705.2080323-1-a.fatoum@pengutronix.de>
 <20220513145705.2080323-3-a.fatoum@pengutronix.de>
 <1c6a5ce2564c29a06eca255072a379351a5fc026.camel@linux.ibm.com>
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 <dd488736ab86c0e0b2809b4ce30f1827563b52b2.camel@linux.ibm.com>
From:   Ahmad Fatoum <a.fatoum@pengutronix.de>
In-Reply-To: <dd488736ab86c0e0b2809b4ce30f1827563b52b2.camel@linux.ibm.com>
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Hello Mimi,

On 17.05.22 21:49, Mimi Zohar wrote:
> On Tue, 2022-05-17 at 20:30 +0200, Jason A. Donenfeld wrote:
>> Hi Mimi,
>>
>> On Tue, May 17, 2022 at 02:21:08PM -0400, Mimi Zohar wrote:
>>> On Tue, 2022-05-17 at 19:38 +0200, Jason A. Donenfeld wrote:
>> Apologies in advance if I've missed the mark here; I'm not very familiar
>> with this thread or what it's driving at. If the simple question was
>> just "is get_random_bytes_wait() good to use?" the answer is just "yes"
>> and I can disappear and stop confusing things. :)
> 
> My apologies for your having been brought into this discussion without
> having properly reviewed and summarized the previous thread.   As you
> saw there is a long history.
> 
> Jarrko, Ahmad,  "Trusted" keys, by definition, are based on the TPM
> RNG.  If CAAM trusted key support wants to use kernel RNG by default,
> that's fine.  However defining and allowing a boot command line option
> to use kernel RNG instead of the TPM RNG, needs to be configurable.

The use of kernel RNG for TPM Trusted Keys is already opt-in. The default
is trusted.rng=default, which maintains existing behavior. Users who want
to use kernel RNG instead need to explicitly specify trusted.rng=kernel.

What more is needed?

Cheers,
Ahmad


> 
> thanks,
> 
> Mimi
> 
> 


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