[SLOF] [PATCH 11/16] Measure the static core root of trust for measurements

[Stefan Berger]

On 11/12/2015 12:57 AM, Nikunj A Dadhania wrote:
> Stefan Berger <stefanb at linux.vnet.ibm.com> writes:
>
>> This patch adds support for measuring the static core root of trust
>> (S-CRTM) and logging the measurements.
>>
>> Signed-off-by: Stefan Berger <stefanb at linux.vnet.ibm.com>
>> ---
>>   board-qemu/slof/vio-vtpm-cdriver.fs |  2 ++
>>   lib/libtpm/tcgbios.c                | 37 +++++++++++++++++++++++++++++++++++++
>>   lib/libtpm/tcgbios.h                |  1 +
>>   lib/libtpm/tcgbios_int.h            |  2 ++
>>   lib/libtpm/tpm.code                 | 10 ++++++++++
>>   lib/libtpm/tpm.in                   |  1 +
>>   slof/fs/tpm/tpm-static.fs           | 11 +++++++++++
>>   7 files changed, 64 insertions(+)
>>
>> diff --git a/board-qemu/slof/vio-vtpm-cdriver.fs b/board-qemu/slof/vio-vtpm-cdriver.fs
>> index 2fc1657..0b4ba41 100644
>> --- a/board-qemu/slof/vio-vtpm-cdriver.fs
>> +++ b/board-qemu/slof/vio-vtpm-cdriver.fs
>> @@ -72,3 +72,5 @@ vtpm-init
>>
>>   \ setup the log
>>   include vtpm-sml.fs
>> +
>> +vtpm-measure-scrtm
>> diff --git a/lib/libtpm/tcgbios.c b/lib/libtpm/tcgbios.c
>> index 40557d6..adec313 100644
>> --- a/lib/libtpm/tcgbios.c
>> +++ b/lib/libtpm/tcgbios.c
>> @@ -1383,3 +1383,40 @@ bool tpm_is_working(void)
>>   {
>>   	return has_working_tpm();
>>   }
>> +
>> +uint32_t tpm_measure_scrtm(void)
>> +{
>> +	uint32_t rc;
>> +
>> +	extern long print_version, print_version_end;
>> +	extern long _slof_data, _slof_data_end;
>> +
>> +	char *version_start = (char *)&print_version;
>> +	uint32_t version_length = (long)&print_version_end - (long)&print_version;
>> +
>> +	char *slof_start = (char *)&_slof_data;
>> +	uint32_t slof_length = (long)&_slof_data_end - (long)&_slof_data;
>> +
>> +	const char *scrtm = "S-CRTM Contents";
>> +
>> +	dprintf("Measure S-CRTM Version: addr = %p, length = %d\n",
>> +		version_start, version_length);
>> +
>> +	rc = tpm_add_measurement_to_log(
>> +		0, EV_S_CRTM_VERSION,
>> +		version_start, version_length,
>> +		(uint8_t *)version_start, version_length);
>> +
>> +	if (rc)
>> +		return rc;
>> +
>> +	dprintf("Measure S-CRTM Content: start = %p, length = %d\n",
>> +		&slof_start, slof_length);
>> +
>> +	rc = tpm_add_measurement_to_log(
>> +		0, EV_S_CRTM_CONTENTS,
>> +		scrtm, strlen(scrtm),
>> +		(uint8_t *)slof_start, slof_length);
>> +
>> +	return rc;
>> +}
>> diff --git a/lib/libtpm/tcgbios.h b/lib/libtpm/tcgbios.h
>> index 902ea1f..9f07caf 100644
>> --- a/lib/libtpm/tcgbios.h
>> +++ b/lib/libtpm/tcgbios.h
>> @@ -24,6 +24,7 @@ enum ipltype {
>>
>>   uint32_t tpm_start(void);
>>   uint32_t tpm_unassert_pp(void);
>> +uint32_t tpm_measure_scrtm(void);
>>   void tpm_set_log_parameters(void *address, unsigned int size);
>>   uint32_t tpm_get_logsize(void);
>>   uint32_t tpm_ipl(enum ipltype bootcd, const uint8_t *addr, uint32_t length);
>> diff --git a/lib/libtpm/tcgbios_int.h b/lib/libtpm/tcgbios_int.h
>> index 420049f..bedc2f1 100644
>> --- a/lib/libtpm/tcgbios_int.h
>> +++ b/lib/libtpm/tcgbios_int.h
>> @@ -57,6 +57,8 @@
>>   #define EV_SEPARATOR             4
>>   #define EV_ACTION                5
>>   #define EV_EVENT_TAG             6
>> +#define EV_S_CRTM_CONTENTS       7
>> +#define EV_S_CRTM_VERSION        8
>>   #define EV_COMPACT_HASH         12
>>   #define EV_IPL                  13
>>   #define EV_IPL_PARTITION_DATA   14
>> diff --git a/lib/libtpm/tpm.code b/lib/libtpm/tpm.code
>> index 66250d5..34b9cbc 100644
>> --- a/lib/libtpm/tpm.code
>> +++ b/lib/libtpm/tpm.code
>> @@ -122,3 +122,13 @@ PRIM(tpm_X2d_is_X2d_working)
>>   	PUSH;
>>   	TOS.n = tpm_is_working();
>>   MIRP
>> +
>> +/************************************************/
>> +/* Have the S-CRTM measured                     */
>> +/* SLOF:   tpm-measure-scrtm  ( -- errcode )    */
>> +/* LIBTPM: errcode = tpm_measure_scrtm          */
>> +/************************************************/
>> +PRIM(tpm_X2d_measure_X2d_scrtm)
>> +	PUSH;
>> +	TOS.n = tpm_measure_scrtm();
>> +MIRP
>> diff --git a/lib/libtpm/tpm.in b/lib/libtpm/tpm.in
>> index f2cc81e..48c0d75 100644
>> --- a/lib/libtpm/tpm.in
>> +++ b/lib/libtpm/tpm.in
>> @@ -23,3 +23,4 @@ cod(tpm-add-bcv)
>>   cod(tpm-process-opcode)
>>   cod(tpm-get-state)
>>   cod(tpm-is-working)
>> +cod(tpm-measure-scrtm)
>> diff --git a/slof/fs/tpm/tpm-static.fs b/slof/fs/tpm/tpm-static.fs
>> index bc5138a..1bc37c9 100644
>> --- a/slof/fs/tpm/tpm-static.fs
>> +++ b/slof/fs/tpm/tpm-static.fs
>> @@ -33,6 +33,17 @@ false VALUE vtpm-debug?
>>       THEN
>>   ;
>>
>> +: vtpm-measure-scrtm
>> +    vtpm-available? IF
>> +        tpm-measure-scrtm                        ( -- errcode )
> Or at least print a warning on the error.

I'll modify several other functions as well to display an error if the 
return code is != 0 rather than only when debugging is enabled.


>
>> +        vtpm-debug? IF
>> +            ." VTPM: Error code from tpm-measure-scrtm: " . cr
>> +        ELSE
>> +            drop
>> +        THEN
>> +    THEN
>> +;
>> +

Regards,
     Stefan