[PATCH v6 2/3] tpm: vtpm_proxy: Implement request_locality function.
Stefan Berger
stefanb at linux.vnet.ibm.com
Sun Jun 4 20:09:38 UTC 2017
On 06/04/2017 12:27 PM, Jarkko Sakkinen wrote:
> On Sun, Jun 04, 2017 at 06:43:32PM +0300, Jarkko Sakkinen wrote:
>> On Thu, Jun 01, 2017 at 08:34:31PM -0400, Stefan Berger wrote:
>>> On 05/24/2017 08:09 PM, Jarkko Sakkinen wrote:
>>>> On Wed, May 24, 2017 at 07:03:27PM -0400, Stefan Berger wrote:
>>>>> On 05/24/2017 06:21 PM, Jarkko Sakkinen wrote:
>>>>>> On Wed, May 24, 2017 at 05:39:40PM -0400, Stefan Berger wrote:
>>>>>>> Implement the request_locality function. To set the locality on the
>>>>>>> backend we define vendor-specific TPM 1.2 and TPM 2 ordinals and send
>>>>>>> a command to the backend to set the locality for the next commands.
>>>>>>>
>>>>>>> To avoid recursing into requesting the locality, we set the
>>>>>>> TPM_TRANSMIT_RAW flag when calling tpm_transmit_cmd. To avoid recursing
>>>>>>> into TPM 2 space related commands, we set the space parameter to NULL.
>>>>>>>
>>>>>>> Signed-off-by: Stefan Berger <stefanb at linux.vnet.ibm.com>
>>>>>>> ---
>>>>>>> drivers/char/tpm/tpm-interface.c | 1 +
>>>>>>> drivers/char/tpm/tpm_vtpm_proxy.c | 36 ++++++++++++++++++++++++++++++++++++
>>>>>>> include/uapi/linux/vtpm_proxy.h | 4 ++++
>>>>>>> 3 files changed, 41 insertions(+)
>>>>>>>
>>>>>>> diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
>>>>>>> index 2eacda2..876d45f 100644
>>>>>>> --- a/drivers/char/tpm/tpm-interface.c
>>>>>>> +++ b/drivers/char/tpm/tpm-interface.c
>>>>>>> @@ -537,6 +537,7 @@ ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_space *space,
>>>>>>> return 0;
>>>>>>> }
>>>>>>> +EXPORT_SYMBOL_GPL(tpm_transmit_cmd);
>>>>>>> #define TPM_DIGEST_SIZE 20
>>>>>>> #define TPM_RET_CODE_IDX 6
>>>>>>> diff --git a/drivers/char/tpm/tpm_vtpm_proxy.c b/drivers/char/tpm/tpm_vtpm_proxy.c
>>>>>>> index 751059d..66024bf 100644
>>>>>>> --- a/drivers/char/tpm/tpm_vtpm_proxy.c
>>>>>>> +++ b/drivers/char/tpm/tpm_vtpm_proxy.c
>>>>>>> @@ -371,6 +371,41 @@ static bool vtpm_proxy_tpm_req_canceled(struct tpm_chip *chip, u8 status)
>>>>>>> return ret;
>>>>>>> }
>>>>>>> +static int vtpm_proxy_request_locality(struct tpm_chip *chip, int locality)
>>>>>>> +{
>>>>>>> + struct tpm_buf buf;
>>>>>>> + int rc;
>>>>>>> + const struct tpm_output_header *header;
>>>>>>> +
>>>>>>> + if (chip->flags & TPM_CHIP_FLAG_TPM2)
>>>>>>> + rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS,
>>>>>>> + TPM2_CC_SET_LOCALITY);
>>>>>> I would always go with this branch.
>>>>>>
>>>>>>> + else
>>>>>>> + rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND,
>>>>>>> + TPM_ORD_SET_LOCALITY);
>>>>>>> + if (rc)
>>>>>>> + return rc;
>>>>>>> + tpm_buf_append_u8(&buf, locality);
>>>>>>> +
>>>>>>> + rc = tpm_transmit_cmd(chip, NULL, buf.data, tpm_buf_length(&buf), 0,
>>>>>>> + TPM_TRANSMIT_UNLOCKED | TPM_TRANSMIT_RAW,
>>>>>>> + "attempting to set locality");
>>>>>>> + if (rc < 0) {
>>>>>>> + locality = rc;
>>>>>>> + goto out;
>>>>>>> + }
>>>>>>> +
>>>>>>> + header = (const struct tpm_output_header *)buf.data;
>>>>>>> + rc = be32_to_cpu(header->return_code);
>>>>>>> + if (rc)
>>>>>>> + locality = -1;
>>>>>>> +
>>>>>>> +out:
>>>>>>> + tpm_buf_destroy(&buf);
>>>>>>> +
>>>>>>> + return locality;
>>>>>>> +}
>>>>>>> +
>>>>>>> static const struct tpm_class_ops vtpm_proxy_tpm_ops = {
>>>>>>> .flags = TPM_OPS_AUTO_STARTUP,
>>>>>>> .recv = vtpm_proxy_tpm_op_recv,
>>>>>>> @@ -380,6 +415,7 @@ static const struct tpm_class_ops vtpm_proxy_tpm_ops = {
>>>>>>> .req_complete_mask = VTPM_PROXY_REQ_COMPLETE_FLAG,
>>>>>>> .req_complete_val = VTPM_PROXY_REQ_COMPLETE_FLAG,
>>>>>>> .req_canceled = vtpm_proxy_tpm_req_canceled,
>>>>>>> + .request_locality = vtpm_proxy_request_locality,
>>>>>>> };
>>>>>>> /*
>>>>>>> diff --git a/include/uapi/linux/vtpm_proxy.h b/include/uapi/linux/vtpm_proxy.h
>>>>>>> index a69e991..58ac73c 100644
>>>>>>> --- a/include/uapi/linux/vtpm_proxy.h
>>>>>>> +++ b/include/uapi/linux/vtpm_proxy.h
>>>>>>> @@ -46,4 +46,8 @@ struct vtpm_proxy_new_dev {
>>>>>>> #define VTPM_PROXY_IOC_NEW_DEV _IOWR(0xa1, 0x00, struct vtpm_proxy_new_dev)
>>>>>>> +/* vendor specific commands to set locality */
>>>>>>> +#define TPM2_CC_SET_LOCALITY 0x20001000
>>>>>>> +#define TPM_ORD_SET_LOCALITY 0x20001000
>>>>>>> +
>>>>>>> #endif /* _UAPI_LINUX_VTPM_PROXY_H */
>>>>>>> --
>>>>>>> 2.4.3
>>>>>> What practical benefit you get from these two constants? I understand
>>>>>> the value range but not so much the redundant code.
>>>>> If you want to change this, please go ahead and give it a sinle name.
>>>>> For the code branches above I think that we should at least send a TPM 1.2
>>>>> formatted command in case of TPM 1.2 and a TPM 2 formatted one in case of
>>>>> TPM 2. It seems just 'proper.'
>>>>>
>>>>> Stefan
>>>> Agreed. I will make these changes no need to send new series.
>>> I pushed an update to the test suite, which may help the cause to accept
>>> this series.
>>>
>>> https://github.com/stefanberger/linux-vtpm-tests
>>>
>>> Patch 3/3 should probably not return -EFAULT in case of the user trying to
>>> send the SetLocality command via /dev/tpm%d but rather -EPIPE to get the
>>> logging of the error suppressed, even though that doesn't seem to be the
>>> right error code.
>>>
>>>
>>> Stefan
>>>
>>>> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen at linux.intel.com>
>>>>
>>>> /Jarkko
>>>>
>> On hold as there are more high priority bug fixes in the queue.
>>
>> /Jarkko
> Patches are now applied to master (bleeding edge) brach. After they are
> tested they can be put also to the next branch.
Thanks. Pulled and tested.
Tested-by: Stefan Berger <stefanb at linux.vnet.ibm.com>
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