Re: [tpmdd-devel] [PATCH RFC 2/2] tpm: refactor tpm2_get_tpm_pt to tpm2_getcap_cmd

[Jarkko Sakkinen]

On Thu, Nov 24, 2016 at 07:12:57PM +0530, Nayna wrote:
> 
> 
> On 11/15/2016 05:18 AM, Jarkko Sakkinen wrote:
> > On Fri, Nov 11, 2016 at 04:02:43PM -0800, Jarkko Sakkinen wrote:
> > > On Fri, Nov 11, 2016 at 09:51:45AM +0530, Nayna wrote:
> > > > 
> > > > 
> > > > On 10/09/2016 03:44 PM, Jarkko Sakkinen wrote:
> > > > > Refactored tpm2_get_tpm_pt to tpm2_getcap_cmd, which means that it 
> > > > > also
> > > > > takes capability ID as input. This is required to access
> > > > > TPM_CAP_HANDLES, which contains metadata needed for swapping transient
> > > > > data.
> > > > > 
> > > > > Signed-off-by: Jarkko Sakkinen 
> > > > > ---
> > > > >drivers/char/tpm/tpm.h  |  6 +++-
> > > > >drivers/char/tpm/tpm2-cmd.c | 64 
> > > > > -
> > > > >drivers/char/tpm/tpm_tis_core.c |  3 +-
> > > > >3 files changed, 38 insertions(+), 35 deletions(-)
> > > > > 
> > > > > diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
> > > > > index 0fab6d5..8176f42 100644
> > > > > --- a/drivers/char/tpm/tpm.h
> > > > > +++ b/drivers/char/tpm/tpm.h
> > > > > @@ -85,6 +85,10 @@ enum tpm2_capabilities {
> > > > >   TPM2_CAP_TPM_PROPERTIES = 6,
> > > > >};
> > > > > 
> > > > > +enum tpm2_properties {
> > > > > + TPM2_PT_FAMILY_INDICATOR= 0x100,
> > > > > +};
> > > > > +
> > > > >enum tpm2_startup_types {
> > > > >   TPM2_SU_CLEAR   = 0x,
> > > > >   TPM2_SU_STATE   = 0x0001,
> > > > > @@ -485,7 +489,7 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
> > > > >int tpm2_unseal_trusted(struct tpm_chip *chip,
> > > > >   struct trusted_key_payload *payload,
> > > > >   struct trusted_key_options *options);
> > > > > -ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,
> > > > > +ssize_t tpm2_getcap_cmd(struct tpm_chip *chip, u32 cap_id, u32 
> > > > > property_id,
> > > > >   u32 *value, const char *desc);
> > > > > 
> > > > >int tpm2_auto_startup(struct tpm_chip *chip);
> > > > > diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
> > > > > index 2900e18..fcf3d86 100644
> > > > > --- a/drivers/char/tpm/tpm2-cmd.c
> > > > > +++ b/drivers/char/tpm/tpm2-cmd.c
> > > > > @@ -111,13 +111,13 @@ struct tpm2_pcr_extend_in {
> > > > >   u8  digest[TPM_DIGEST_SIZE];
> > > > >} __packed;
> > > > > 
> > > > > -struct tpm2_get_tpm_pt_in {
> > > > > +struct tpm2_getcap_in {
> > > > >   __be32  cap_id;
> > > > >   __be32  property_id;
> > > > >   __be32  property_cnt;
> > > > >} __packed;
> > > > > 
> > > > > -struct tpm2_get_tpm_pt_out {
> > > > > +struct tpm2_getcap_out {
> > > > >   u8  more_data;
> > > > >   __be32  subcap_id;
> > > > >   __be32  property_cnt;
> > > > > @@ -140,8 +140,8 @@ union tpm2_cmd_params {
> > > > >   struct  tpm2_pcr_read_inpcrread_in;
> > > > >   struct  tpm2_pcr_read_out   pcrread_out;
> > > > >   struct  tpm2_pcr_extend_in  pcrextend_in;
> > > > > - struct  tpm2_get_tpm_pt_in  get_tpm_pt_in;
> > > > > - struct  tpm2_get_tpm_pt_out get_tpm_pt_out;
> > > > > + struct  tpm2_getcap_in  getcap_in;
> > > > > + struct  tpm2_getcap_out getcap_out;
> > > > >   struct  tpm2_get_random_in  getrandom_in;
> > > > >   struct  tpm2_get_random_out getrandom_out;
> > > > >};
> > > > > @@ -435,16 +435,6 @@ int tpm2_get_random(struct tpm_chip *chip, u8 
> > > > > *out, size_t max)
> > > > >   return total ? total : -EIO;
> > > > >}
> > > > > 
> > > > > -#define TPM2_GET_TPM_PT_IN_SIZE \
> > > > > - (sizeof(struct tpm_input_header) + \
> > > > > -  sizeof(struct tpm2_get_tpm_pt_in))
> > > > > -
> > > > > -static const struct tpm_input_header tpm2_get_tpm_pt_header = {
> > > > > - .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
> > > > > - .length = cpu_to_be32(TPM2_GET_TPM_PT_IN_SIZE),
> > > > > - .ordinal = cpu_to_be32(TPM2_CC_GET_CAPABILITY)
> > > > > -};
> > > > > -
> > > > >/**
> > > > > * Append TPMS_AUTH_COMMAND to the buffer. The buffer must be 
> > > > > allocated with
> > > > > * tpm_buf_alloc().
> > > > > @@ -750,35 +740,43 @@ out:
> > > > >   return rc;
> > > > >}
> > > > > 
> > > > > +#define TPM2_GETCAP_IN_SIZE \
> > > > > + (sizeof(struct tpm_input_header) + sizeof(struct 
> > > > > tpm2_getcap_in))
> > > > > +
> > > > > +static const struct tpm_input_header tpm2_getcap_header = {
> > > > > + .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
> > > > > + .length = cpu_to_be32(TPM2_GETCAP_IN_SIZE),
> > > > > + .ordinal = cpu_to_be32(TPM2_CC_GET_CAPABILITY)
> > > > > +};
> > > > > +
> > > > >/**
> > > > > - * tpm2_get_tpm_pt() - get value of a TPM_CAP_TPM_PROPERTIES type 
> > > > > property
> > > > > - * @chip:TPM chip to use.
> > > > > - * @property_id: property ID.
> > > > 

Re: [tpmdd-devel] [PATCH RFC 2/2] tpm: refactor tpm2_get_tpm_pt to tpm2_getcap_cmd

[Jarkko Sakkinen]

On Tue, Nov 22, 2016 at 02:38:21PM +0530, Nayna wrote:
> 
> 
> On 11/18/2016 09:43 PM, Jarkko Sakkinen wrote:
> > On Fri, Nov 18, 2016 at 05:42:01PM +0530, Nayna wrote:
> > > 
> > > 
> > > On 11/17/2016 11:12 PM, Jarkko Sakkinen wrote:
> > > > On Thu, Nov 17, 2016 at 05:20:36PM +0530, Nayna wrote:
> > > > 
> > > > > I tested this for capability TPM2_CAP_PCRS. It seems TPM2_CAP_PCRS
> > > > > capability always returns full PCR allocation, and more_data as 0, 
> > > > > So, I
> > > > > think the idea of looping over based on more_data may not work for 
> > > > > this
> > > > > capability.
> > > > 
> > > > You can always request one value at a time until there's no more.
> > > > 
> > > > If you request N values, depending on the hardware, the hardware returns
> > > > to you anything from 1 to N values. If you implement a function that
> > > > requests N values in the command, you *must* handle the case where
> > > > moreData is 1 even if the hardware you are testing that never happens.
> > > > 
> > > > That's the reason why I would start with a function that you request one
> > > > property of one capability and optimize it in future if it doesn't scale
> > > > for some workload.
> > > > 
> > > > Do you have a workload where it doesn't scale?
> > > 
> > > Thanks Jarkko for explaining in detail.
> > > 
> > > If I understood correctly, the idea is to request for one property at a
> > > time, and if we need multiple properties, then to request for each of them
> > > in a loop. In case of TPM2_CAP_PCRS, property is always zero. This is how 
> > > I
> > > am calling getcap_cmd for TPM2_CAP_PCRS.
> > > 
> > > tpm2_getcap_cmd(chip, TPM2_CAP_PCRS, 0, _data, "get active pcr 
> > > banks");
> > > 
> > > Output :
> > > 
> > > [   17.081665] tpm: cap id to receive value is 2
> > > [   17.081666] tpm: TPM2_CAP_COMMANDS: more data 1
> > > [   17.081667] tpm: 2
> > > [   17.081668] tpm: tpm2_get_active_banks  ---> cap is TPM2_CAP_PCRS
> > > [   17.171665] tpm: cap id to receive value is 5
> > > [   17.171666] tpm: TPM2_CAP_PCRS: more data 0 ---> more data is zero.
> > > [   17.171666] tpm: TPM2_CAP_PCRS: more data 0
> > > [   17.171667] tpm: count pcr banks is 2 --> count of active pcr banks
> > > information returned
> > > 
> > > more_data is always zero here, so am not sure how to handle more_data in
> > > this case ?
> > > Since property_id is always zero, I am not able to request for one 
> > > property
> > > at a time.
> > > and response_buffer returns the details for both active banks.
> > > 
> > > This is the expected behavior defined in TCG 2.0 Part 3 Commands
> > > Specification (Section 30.2.1):
> > > 
> > > "TPM_CAP_PCRS – Returns the current allocation of PCR in a
> > > TPML_PCR_SELECTION. The property parameter shall be zero. The TPM will
> > > always respond to this command with the full PCR allocation and moreData
> > > will be NO."
> > > 
> > > Please let me know, if I am missing something.
> > 
> > Thanks for pointing that. I think you got it right and I had some wrong
> > assumptions about 'moreData'.
> > 
> > Here's what I propose. Do a non-generic function just for getting CAP_PCRS.
> > You could call it tpm2_get_pcr_allocation() as you don't want or rather
> > need to handle all the bells and whistles in that TPM command.
> > 
> > It makes a lot more sense now than having one-size-for-all function.
> 
> Thanks Jarkko, Yeah, Sure, I will write it as different non-generic call.
> Otherwise, the function works good.
> Also, I am thinking now I can write "multi-bank support for extend" on top
> of master branch itself.  Any issues with that ?

I'm not sure what exactly I should or should not have an issue with.

I can check the patch but won't apply or test it before it is used for
something if that is what you are asking.

/Jarkko

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Re: [tpmdd-devel] [PATCH RFC 2/2] tpm: refactor tpm2_get_tpm_pt to tpm2_getcap_cmd

[Nayna]

On 11/17/2016 11:12 PM, Jarkko Sakkinen wrote:
> On Thu, Nov 17, 2016 at 05:20:36PM +0530, Nayna wrote:
>
>> I tested this for capability TPM2_CAP_PCRS. It seems TPM2_CAP_PCRS
>> capability always returns full PCR allocation, and more_data as 0, So, I
>> think the idea of looping over based on more_data may not work for this
>> capability.
>
> You can always request one value at a time until there's no more.
>
> If you request N values, depending on the hardware, the hardware returns
> to you anything from 1 to N values. If you implement a function that
> requests N values in the command, you *must* handle the case where
> moreData is 1 even if the hardware you are testing that never happens.
>
> That's the reason why I would start with a function that you request one
> property of one capability and optimize it in future if it doesn't scale
> for some workload.
>
> Do you have a workload where it doesn't scale?

Thanks Jarkko for explaining in detail.

If I understood correctly, the idea is to request for one property at a 
time, and if we need multiple properties, then to request for each of 
them in a loop. In case of TPM2_CAP_PCRS, property is always zero. This 
is how I am calling getcap_cmd for TPM2_CAP_PCRS.

tpm2_getcap_cmd(chip, TPM2_CAP_PCRS, 0, _data, "get active pcr 
banks");

Output :

[   17.081665] tpm: cap id to receive value is 2
[   17.081666] tpm: TPM2_CAP_COMMANDS: more data 1
[   17.081667] tpm: 2
[   17.081668] tpm: tpm2_get_active_banks  ---> cap is TPM2_CAP_PCRS
[   17.171665] tpm: cap id to receive value is 5
[   17.171666] tpm: TPM2_CAP_PCRS: more data 0 ---> more data is zero.
[   17.171666] tpm: TPM2_CAP_PCRS: more data 0
[   17.171667] tpm: count pcr banks is 2 --> count of active pcr 
banks information returned

more_data is always zero here, so am not sure how to handle more_data in 
this case ?
Since property_id is always zero, I am not able to request for one 
property at a time.
and response_buffer returns the details for both active banks.

This is the expected behavior defined in TCG 2.0 Part 3 Commands 
Specification (Section 30.2.1):

"TPM_CAP_PCRS – Returns the current allocation of PCR in a 
TPML_PCR_SELECTION. The property parameter shall be zero. The TPM will 
always respond to this command with the full PCR allocation and moreData 
will be NO."

Please let me know, if I am missing something.

Thanks & Regards,
- Nayna


>
> /Jarkko
>


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Re: [tpmdd-devel] [PATCH RFC 2/2] tpm: refactor tpm2_get_tpm_pt to tpm2_getcap_cmd

[Nayna]

On 11/12/2016 05:32 AM, Jarkko Sakkinen wrote:
> On Fri, Nov 11, 2016 at 09:51:45AM +0530, Nayna wrote:
>>
>>
>> On 10/09/2016 03:44 PM, Jarkko Sakkinen wrote:
>>> Refactored tpm2_get_tpm_pt to tpm2_getcap_cmd, which means that it also
>>> takes capability ID as input. This is required to access
>>> TPM_CAP_HANDLES, which contains metadata needed for swapping transient
>>> data.
>>>
>>> Signed-off-by: Jarkko Sakkinen 
>>> ---
>>>drivers/char/tpm/tpm.h  |  6 +++-
>>>drivers/char/tpm/tpm2-cmd.c | 64 
>>> -
>>>drivers/char/tpm/tpm_tis_core.c |  3 +-
>>>3 files changed, 38 insertions(+), 35 deletions(-)
>>>
>>> diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
>>> index 0fab6d5..8176f42 100644
>>> --- a/drivers/char/tpm/tpm.h
>>> +++ b/drivers/char/tpm/tpm.h
>>> @@ -85,6 +85,10 @@ enum tpm2_capabilities {
>>> TPM2_CAP_TPM_PROPERTIES = 6,
>>>};
>>>
>>> +enum tpm2_properties {
>>> +   TPM2_PT_FAMILY_INDICATOR= 0x100,
>>> +};
>>> +
>>>enum tpm2_startup_types {
>>> TPM2_SU_CLEAR   = 0x,
>>> TPM2_SU_STATE   = 0x0001,
>>> @@ -485,7 +489,7 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
>>>int tpm2_unseal_trusted(struct tpm_chip *chip,
>>> struct trusted_key_payload *payload,
>>> struct trusted_key_options *options);
>>> -ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,
>>> +ssize_t tpm2_getcap_cmd(struct tpm_chip *chip, u32 cap_id, u32 property_id,
>>> u32 *value, const char *desc);
>>>
>>>int tpm2_auto_startup(struct tpm_chip *chip);
>>> diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
>>> index 2900e18..fcf3d86 100644
>>> --- a/drivers/char/tpm/tpm2-cmd.c
>>> +++ b/drivers/char/tpm/tpm2-cmd.c
>>> @@ -111,13 +111,13 @@ struct tpm2_pcr_extend_in {
>>> u8  digest[TPM_DIGEST_SIZE];
>>>} __packed;
>>>
>>> -struct tpm2_get_tpm_pt_in {
>>> +struct tpm2_getcap_in {
>>> __be32  cap_id;
>>> __be32  property_id;
>>> __be32  property_cnt;
>>>} __packed;
>>>
>>> -struct tpm2_get_tpm_pt_out {
>>> +struct tpm2_getcap_out {
>>> u8  more_data;
>>> __be32  subcap_id;
>>> __be32  property_cnt;
>>> @@ -140,8 +140,8 @@ union tpm2_cmd_params {
>>> struct  tpm2_pcr_read_inpcrread_in;
>>> struct  tpm2_pcr_read_out   pcrread_out;
>>> struct  tpm2_pcr_extend_in  pcrextend_in;
>>> -   struct  tpm2_get_tpm_pt_in  get_tpm_pt_in;
>>> -   struct  tpm2_get_tpm_pt_out get_tpm_pt_out;
>>> +   struct  tpm2_getcap_in  getcap_in;
>>> +   struct  tpm2_getcap_out getcap_out;
>>> struct  tpm2_get_random_in  getrandom_in;
>>> struct  tpm2_get_random_out getrandom_out;
>>>};
>>> @@ -435,16 +435,6 @@ int tpm2_get_random(struct tpm_chip *chip, u8 *out, 
>>> size_t max)
>>> return total ? total : -EIO;
>>>}
>>>
>>> -#define TPM2_GET_TPM_PT_IN_SIZE \
>>> -   (sizeof(struct tpm_input_header) + \
>>> -sizeof(struct tpm2_get_tpm_pt_in))
>>> -
>>> -static const struct tpm_input_header tpm2_get_tpm_pt_header = {
>>> -   .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
>>> -   .length = cpu_to_be32(TPM2_GET_TPM_PT_IN_SIZE),
>>> -   .ordinal = cpu_to_be32(TPM2_CC_GET_CAPABILITY)
>>> -};
>>> -
>>>/**
>>> * Append TPMS_AUTH_COMMAND to the buffer. The buffer must be allocated 
>>> with
>>> * tpm_buf_alloc().
>>> @@ -750,35 +740,43 @@ out:
>>> return rc;
>>>}
>>>
>>> +#define TPM2_GETCAP_IN_SIZE \
>>> +   (sizeof(struct tpm_input_header) + sizeof(struct tpm2_getcap_in))
>>> +
>>> +static const struct tpm_input_header tpm2_getcap_header = {
>>> +   .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
>>> +   .length = cpu_to_be32(TPM2_GETCAP_IN_SIZE),
>>> +   .ordinal = cpu_to_be32(TPM2_CC_GET_CAPABILITY)
>>> +};
>>> +
>>>/**
>>> - * tpm2_get_tpm_pt() - get value of a TPM_CAP_TPM_PROPERTIES type property
>>> - * @chip:  TPM chip to use.
>>> - * @property_id:   property ID.
>>> - * @value: output variable.
>>> + * tpm2_getcap_cmd() - execute a TPM2_GetCapability command
>>> + * @chip:  TPM chip to use
>>> + * @cap_id:capability ID
>>> + * @property_id:   property ID
>>> + * @value: value of the property
>>> * @desc:passed to tpm_transmit_cmd()
>>> *
>>> - * 0 is returned when the operation is successful. If a negative number is
>>> - * returned it remarks a POSIX error code. If a positive number is returned
>>> - * it remarks a TPM error.
>>> + * Return: same as with tpm_transmit_cmd
>>> */
>>> -ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,  u32 
>>> *value,
>>> -   const char *desc)
>>> +ssize_t tpm2_getcap_cmd(struct tpm_chip *chip, u32 cap_id, u32 property_id,
>>> +   u32 *value, const char *desc)
>>
>> This function currently returns single 

Re: [tpmdd-devel] [PATCH RFC 2/2] tpm: refactor tpm2_get_tpm_pt to tpm2_getcap_cmd

[Jarkko Sakkinen]

On Fri, Nov 11, 2016 at 09:51:45AM +0530, Nayna wrote:
> 
> 
> On 10/09/2016 03:44 PM, Jarkko Sakkinen wrote:
> > Refactored tpm2_get_tpm_pt to tpm2_getcap_cmd, which means that it also
> > takes capability ID as input. This is required to access
> > TPM_CAP_HANDLES, which contains metadata needed for swapping transient
> > data.
> > 
> > Signed-off-by: Jarkko Sakkinen 
> > ---
> >   drivers/char/tpm/tpm.h  |  6 +++-
> >   drivers/char/tpm/tpm2-cmd.c | 64 
> > -
> >   drivers/char/tpm/tpm_tis_core.c |  3 +-
> >   3 files changed, 38 insertions(+), 35 deletions(-)
> > 
> > diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
> > index 0fab6d5..8176f42 100644
> > --- a/drivers/char/tpm/tpm.h
> > +++ b/drivers/char/tpm/tpm.h
> > @@ -85,6 +85,10 @@ enum tpm2_capabilities {
> > TPM2_CAP_TPM_PROPERTIES = 6,
> >   };
> > 
> > +enum tpm2_properties {
> > +   TPM2_PT_FAMILY_INDICATOR= 0x100,
> > +};
> > +
> >   enum tpm2_startup_types {
> > TPM2_SU_CLEAR   = 0x,
> > TPM2_SU_STATE   = 0x0001,
> > @@ -485,7 +489,7 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
> >   int tpm2_unseal_trusted(struct tpm_chip *chip,
> > struct trusted_key_payload *payload,
> > struct trusted_key_options *options);
> > -ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,
> > +ssize_t tpm2_getcap_cmd(struct tpm_chip *chip, u32 cap_id, u32 property_id,
> > u32 *value, const char *desc);
> > 
> >   int tpm2_auto_startup(struct tpm_chip *chip);
> > diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
> > index 2900e18..fcf3d86 100644
> > --- a/drivers/char/tpm/tpm2-cmd.c
> > +++ b/drivers/char/tpm/tpm2-cmd.c
> > @@ -111,13 +111,13 @@ struct tpm2_pcr_extend_in {
> > u8  digest[TPM_DIGEST_SIZE];
> >   } __packed;
> > 
> > -struct tpm2_get_tpm_pt_in {
> > +struct tpm2_getcap_in {
> > __be32  cap_id;
> > __be32  property_id;
> > __be32  property_cnt;
> >   } __packed;
> > 
> > -struct tpm2_get_tpm_pt_out {
> > +struct tpm2_getcap_out {
> > u8  more_data;
> > __be32  subcap_id;
> > __be32  property_cnt;
> > @@ -140,8 +140,8 @@ union tpm2_cmd_params {
> > struct  tpm2_pcr_read_inpcrread_in;
> > struct  tpm2_pcr_read_out   pcrread_out;
> > struct  tpm2_pcr_extend_in  pcrextend_in;
> > -   struct  tpm2_get_tpm_pt_in  get_tpm_pt_in;
> > -   struct  tpm2_get_tpm_pt_out get_tpm_pt_out;
> > +   struct  tpm2_getcap_in  getcap_in;
> > +   struct  tpm2_getcap_out getcap_out;
> > struct  tpm2_get_random_in  getrandom_in;
> > struct  tpm2_get_random_out getrandom_out;
> >   };
> > @@ -435,16 +435,6 @@ int tpm2_get_random(struct tpm_chip *chip, u8 *out, 
> > size_t max)
> > return total ? total : -EIO;
> >   }
> > 
> > -#define TPM2_GET_TPM_PT_IN_SIZE \
> > -   (sizeof(struct tpm_input_header) + \
> > -sizeof(struct tpm2_get_tpm_pt_in))
> > -
> > -static const struct tpm_input_header tpm2_get_tpm_pt_header = {
> > -   .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
> > -   .length = cpu_to_be32(TPM2_GET_TPM_PT_IN_SIZE),
> > -   .ordinal = cpu_to_be32(TPM2_CC_GET_CAPABILITY)
> > -};
> > -
> >   /**
> >* Append TPMS_AUTH_COMMAND to the buffer. The buffer must be allocated 
> > with
> >* tpm_buf_alloc().
> > @@ -750,35 +740,43 @@ out:
> > return rc;
> >   }
> > 
> > +#define TPM2_GETCAP_IN_SIZE \
> > +   (sizeof(struct tpm_input_header) + sizeof(struct tpm2_getcap_in))
> > +
> > +static const struct tpm_input_header tpm2_getcap_header = {
> > +   .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
> > +   .length = cpu_to_be32(TPM2_GETCAP_IN_SIZE),
> > +   .ordinal = cpu_to_be32(TPM2_CC_GET_CAPABILITY)
> > +};
> > +
> >   /**
> > - * tpm2_get_tpm_pt() - get value of a TPM_CAP_TPM_PROPERTIES type property
> > - * @chip:  TPM chip to use.
> > - * @property_id:   property ID.
> > - * @value: output variable.
> > + * tpm2_getcap_cmd() - execute a TPM2_GetCapability command
> > + * @chip:  TPM chip to use
> > + * @cap_id:capability ID
> > + * @property_id:   property ID
> > + * @value: value of the property
> >* @desc: passed to tpm_transmit_cmd()
> >*
> > - * 0 is returned when the operation is successful. If a negative number is
> > - * returned it remarks a POSIX error code. If a positive number is returned
> > - * it remarks a TPM error.
> > + * Return: same as with tpm_transmit_cmd
> >*/
> > -ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,  u32 
> > *value,
> > -   const char *desc)
> > +ssize_t tpm2_getcap_cmd(struct tpm_chip *chip, u32 cap_id, u32 property_id,
> > +   u32 *value, const char *desc)
> 
> This function currently returns single value "u32 *value" as output data.
> 
> Some calling function expect list 

Re: [tpmdd-devel] [PATCH RFC 2/2] tpm: refactor tpm2_get_tpm_pt to tpm2_getcap_cmd

[Nayna]

On 10/09/2016 03:44 PM, Jarkko Sakkinen wrote:
> Refactored tpm2_get_tpm_pt to tpm2_getcap_cmd, which means that it also
> takes capability ID as input. This is required to access
> TPM_CAP_HANDLES, which contains metadata needed for swapping transient
> data.
>
> Signed-off-by: Jarkko Sakkinen 
> ---
>   drivers/char/tpm/tpm.h  |  6 +++-
>   drivers/char/tpm/tpm2-cmd.c | 64 
> -
>   drivers/char/tpm/tpm_tis_core.c |  3 +-
>   3 files changed, 38 insertions(+), 35 deletions(-)
>
> diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
> index 0fab6d5..8176f42 100644
> --- a/drivers/char/tpm/tpm.h
> +++ b/drivers/char/tpm/tpm.h
> @@ -85,6 +85,10 @@ enum tpm2_capabilities {
>   TPM2_CAP_TPM_PROPERTIES = 6,
>   };
>
> +enum tpm2_properties {
> + TPM2_PT_FAMILY_INDICATOR= 0x100,
> +};
> +
>   enum tpm2_startup_types {
>   TPM2_SU_CLEAR   = 0x,
>   TPM2_SU_STATE   = 0x0001,
> @@ -485,7 +489,7 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
>   int tpm2_unseal_trusted(struct tpm_chip *chip,
>   struct trusted_key_payload *payload,
>   struct trusted_key_options *options);
> -ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,
> +ssize_t tpm2_getcap_cmd(struct tpm_chip *chip, u32 cap_id, u32 property_id,
>   u32 *value, const char *desc);
>
>   int tpm2_auto_startup(struct tpm_chip *chip);
> diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
> index 2900e18..fcf3d86 100644
> --- a/drivers/char/tpm/tpm2-cmd.c
> +++ b/drivers/char/tpm/tpm2-cmd.c
> @@ -111,13 +111,13 @@ struct tpm2_pcr_extend_in {
>   u8  digest[TPM_DIGEST_SIZE];
>   } __packed;
>
> -struct tpm2_get_tpm_pt_in {
> +struct tpm2_getcap_in {
>   __be32  cap_id;
>   __be32  property_id;
>   __be32  property_cnt;
>   } __packed;
>
> -struct tpm2_get_tpm_pt_out {
> +struct tpm2_getcap_out {
>   u8  more_data;
>   __be32  subcap_id;
>   __be32  property_cnt;
> @@ -140,8 +140,8 @@ union tpm2_cmd_params {
>   struct  tpm2_pcr_read_inpcrread_in;
>   struct  tpm2_pcr_read_out   pcrread_out;
>   struct  tpm2_pcr_extend_in  pcrextend_in;
> - struct  tpm2_get_tpm_pt_in  get_tpm_pt_in;
> - struct  tpm2_get_tpm_pt_out get_tpm_pt_out;
> + struct  tpm2_getcap_in  getcap_in;
> + struct  tpm2_getcap_out getcap_out;
>   struct  tpm2_get_random_in  getrandom_in;
>   struct  tpm2_get_random_out getrandom_out;
>   };
> @@ -435,16 +435,6 @@ int tpm2_get_random(struct tpm_chip *chip, u8 *out, 
> size_t max)
>   return total ? total : -EIO;
>   }
>
> -#define TPM2_GET_TPM_PT_IN_SIZE \
> - (sizeof(struct tpm_input_header) + \
> -  sizeof(struct tpm2_get_tpm_pt_in))
> -
> -static const struct tpm_input_header tpm2_get_tpm_pt_header = {
> - .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
> - .length = cpu_to_be32(TPM2_GET_TPM_PT_IN_SIZE),
> - .ordinal = cpu_to_be32(TPM2_CC_GET_CAPABILITY)
> -};
> -
>   /**
>* Append TPMS_AUTH_COMMAND to the buffer. The buffer must be allocated with
>* tpm_buf_alloc().
> @@ -750,35 +740,43 @@ out:
>   return rc;
>   }
>
> +#define TPM2_GETCAP_IN_SIZE \
> + (sizeof(struct tpm_input_header) + sizeof(struct tpm2_getcap_in))
> +
> +static const struct tpm_input_header tpm2_getcap_header = {
> + .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS),
> + .length = cpu_to_be32(TPM2_GETCAP_IN_SIZE),
> + .ordinal = cpu_to_be32(TPM2_CC_GET_CAPABILITY)
> +};
> +
>   /**
> - * tpm2_get_tpm_pt() - get value of a TPM_CAP_TPM_PROPERTIES type property
> - * @chip:TPM chip to use.
> - * @property_id: property ID.
> - * @value:   output variable.
> + * tpm2_getcap_cmd() - execute a TPM2_GetCapability command
> + * @chip:TPM chip to use
> + * @cap_id:  capability ID
> + * @property_id: property ID
> + * @value:   value of the property
>* @desc:   passed to tpm_transmit_cmd()
>*
> - * 0 is returned when the operation is successful. If a negative number is
> - * returned it remarks a POSIX error code. If a positive number is returned
> - * it remarks a TPM error.
> + * Return: same as with tpm_transmit_cmd
>*/
> -ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,  u32 *value,
> - const char *desc)
> +ssize_t tpm2_getcap_cmd(struct tpm_chip *chip, u32 cap_id, u32 property_id,
> + u32 *value, const char *desc)

This function currently returns single value "u32 *value" as output data.

Some calling function expect list of values from capabilities output.
For eg., get_active_banks() use TPM_CAP_PCRS capability to retrieve list 
of active banks. And this capability returns array of pcr 
selections(which is a struct representing each active PCR bank)

I was