Re: [PATCH v5 12/21] tpm: move pcr extend code to tpm2-cmd.c

[Roberto Sassu <roberto.sassu@huawei.com>]

On 10/4/2018 1:45 PM, Winkler, Tomas wrote:
> 
> 
>> -----Original Message-----
>> From: Jarkko Sakkinen [mailto:jarkko.sakkinen@linux.intel.com]
>> Sent: Thursday, October 04, 2018 14:35
>> To: Winkler, Tomas <tomas.winkler@intel.com>
>> Cc: Jason Gunthorpe <jgg@ziepe.ca>; Nayna Jain
>> <nayna@linux.vnet.ibm.com>; Usyskin, Alexander
>> <alexander.usyskin@intel.com>; Struk, Tadeusz <tadeusz.struk@intel.com>;
>> linux-integrity@vger.kernel.org; linux-security-module@vger.kernel.org;
>> linux-kernel@vger.kernel.org; roberto.sassu@huawei.com
>> Subject: Re: [PATCH v5 12/21] tpm: move pcr extend code to tpm2-cmd.c
>>
>> On Wed, Oct 03, 2018 at 10:24:09PM +0000, Winkler, Tomas wrote:
>>>
>>>
>>>> -----Original Message-----
>>>> From: Jarkko Sakkinen [mailto:jarkko.sakkinen@linux.intel.com]
>>>> Sent: Wednesday, October 03, 2018 15:02
>>>> To: Winkler, Tomas <tomas.winkler@intel.com>
>>>> Cc: Jason Gunthorpe <jgg@ziepe.ca>; Nayna Jain
>>>> <nayna@linux.vnet.ibm.com>; Usyskin, Alexander
>>>> <alexander.usyskin@intel.com>; Struk, Tadeusz
>>>> <tadeusz.struk@intel.com>; linux-integrity@vger.kernel.org;
>>>> linux-security-module@vger.kernel.org;
>>>> linux-kernel@vger.kernel.org; roberto.sassu@huawei.com
>>>> Subject: Re: [PATCH v5 12/21] tpm: move pcr extend code to
>>>> tpm2-cmd.c
>>>>
>>>> On Tue, Oct 02, 2018 at 04:58:25AM +0000, Winkler, Tomas wrote:
>>>>>
>>>>>
>>>>>>
>>>>>> On Sat, Sep 29, 2018 at 01:30:26AM +0300, Tomas Winkler wrote:
>>>>>>> Add tpm2_pcr_extend() function to tpm2-cmd.c with signature
>>>>>>> required by tpm-interface.c. It wraps the original open code
>>>> implementation.
>>>>>>> The original original tpm2_pcr_extend() function is renamed to
>>>>>>> __tpm2_pcr_extend() and made static, it is called only from
>>>>>>> new tpm2_pcr_extend().
>>>>>>>
>>>>>>> Fix warnings in __tpm2_pcr_extend()
>>>>>>> tpm2-cmd.c:251:16: warning: comparison between signed and
>>>>>>> unsigned integer expressions [-Wsign-compare]
>>>>>>> tpm2-cmd.c:252:17: warning: comparison between signed and
>>>>>>> unsigned integer expressions [-Wsign-compare]
>>>>>>>
>>>>>>> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
>>>>>>
>>>>>> We do not want the signature change, especially because as we
>>>>>> are working on getting Roberto's changes in and also because it
>>>>>> has absolutely a zero gain. Who cares if those functions take
>>>>>> different
>>>> parameters? I don't.
>>>>>
>>>>> Yes, we do care this series tries to have a clean cut between 1.x
>>>>> and 2.x
>>>> specs. Please, let's finish one transformation and then move to another.
>>>>> I understand that Roberto will have to rebase anyhow, if this
>>>>> series goes in
>>>> first, if this is hard I can do it myself, it's trivial.
>>>>>
>>>>> Tomas
>>>>
>>>> I'm happy to tune this minor stuff.
>>> What minor stuff?  This patch is just okay, let's change the API in next
>> round.
>>
>> The patch is not okay because it does a completely unnecessary API change.
>   
> There is no API change, in that sense.
> The exported API is in tpm-interface.c int tpm_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash)
> that is used is outside of the tpm reminds the same, only the open coded implementation of tpm2_pcr_extned has moved to
> tpm2-cmd.c, This code is not called out of tpm module.
> Please review the code again.

Hi Tomas

I will update tpm_pcr_extend() by replacing the array of u8 with an
array of tpm2_digest structures, so that the caller can provide multiple
digests with one call. The array of tpm2_digest structures will be
passed to tpm2_pcr_extend(). Please, don't modify the parameters of
tpm2_pcr_extend().

Thanks

Roberto

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