| Message ID | 20180316174528.21018-1-nayna@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi On Fri, Mar 16, 2018 at 11:15:28PM +0530, Nayna Jain wrote: > For selftest being run in the background, the TCG 2.0 Specification > provides the command TPM2_GetTestResult to check the status of selftest > completion. > > When the partial selftest command is sent just after TPM initialization, > it is observed that it returns RC_COMMAND_CODE error, which as per TPM 2.0 When does it return RC_COMMAND_COMMAND return code? Who is observing this? Please, do not use passive form. > Specification, indicates "the response code that is returned if the TPM is > unmarshalling a value that it expects to be a TPM_CC and the input value is > not in the table." This doesn't indicate the exact status of selftest > command on TPM. But, it can be verified by sending the TPM2_GetTestResult. Where did you draw the conclusion that it doesn not indicate the exact status? What does RC_COMMAND_CODE anyway indicate then? Just trying to understand. Also, please check the grammar in last two sentences (the second one should probably be a subordinate clause). > This patch implements the TPM2_GetTestResult command and uses it to check > the selftest status, before sending the full selftest command after partial > selftest returns RC_COMMAND_CODE. Isn't that command implemented inside the TPM? You are implementing tpm2_get_selftest_result(). > With this change, dmesg shows the TPM selftest completed at 1.243864 > compared with the previous 1.939667 time. These numbers mean *absolutely nothing* to me as they are not connected to *anything*. > > Signed-off-by: Nayna Jain <nayna@linux.vnet.ibm.com> > Tested-by: Mimi Zohar <zohar@linux.vnet.ibm.com> (on Pi with TPM 2.0) > Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> > --- > drivers/char/tpm/tpm.h | 2 ++ > drivers/char/tpm/tpm2-cmd.c | 59 +++++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 61 insertions(+) > > diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h > index 82ae7b722161..d95eeb7c002a 100644 > --- a/drivers/char/tpm/tpm.h > +++ b/drivers/char/tpm/tpm.h > @@ -107,6 +107,7 @@ enum tpm2_return_codes { > TPM2_RC_FAILURE = 0x0101, > TPM2_RC_DISABLED = 0x0120, > TPM2_RC_COMMAND_CODE = 0x0143, > + TPM2_RC_NEEDS_TEST = 0x0153, > TPM2_RC_TESTING = 0x090A, /* RC_WARN */ > TPM2_RC_REFERENCE_H0 = 0x0910, > }; > @@ -135,6 +136,7 @@ enum tpm2_command_codes { > TPM2_CC_FLUSH_CONTEXT = 0x0165, > TPM2_CC_GET_CAPABILITY = 0x017A, > TPM2_CC_GET_RANDOM = 0x017B, > + TPM2_CC_GET_TEST_RESULT = 0x017C, > TPM2_CC_PCR_READ = 0x017E, > TPM2_CC_PCR_EXTEND = 0x0182, > TPM2_CC_LAST = 0x018F, > diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c > index 89a5397b18d2..494f6dfbc65d 100644 > --- a/drivers/char/tpm/tpm2-cmd.c > +++ b/drivers/char/tpm/tpm2-cmd.c > @@ -823,6 +823,50 @@ unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal) > EXPORT_SYMBOL_GPL(tpm2_calc_ordinal_duration); > > /** > + * tpm2_get_selftest_result() - get the status of self tests > + * > + * @chip: TPM chip to use > + * > + * Return: If error return rc, else return the result of the self tests. > + * TPM_RC_NEEDS_TESTING: No self tests are done. Needs testing. > + * TPM_RC_TESTING: Self tests are in progress. > + * TPM_RC_SUCCESS: Self tests completed successfully. > + * TPM_RC_FAILURE: Self tests completed failure. > + * > + * This function can be used to check the status of self tests on the TPM. > + */ > +static int tpm2_get_selftest_result(struct tpm_chip *chip) > +{ > + struct tpm_buf buf; > + int rc; > + int test_result; > + uint16_t data_size; > + int len; > + const struct tpm_output_header *header; > + > + rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_TEST_RESULT); > + if (rc) > + return rc; > + > + len = tpm_transmit(chip, NULL, buf.data, PAGE_SIZE, 0); > + if (len < 0) > + return len; > + > + header = (struct tpm_output_header *)buf.data; > + > + rc = be32_to_cpu(header->return_code); > + if (rc) > + return rc; > + > + data_size = be16_to_cpup((__be16 *)&buf.data[TPM_HEADER_SIZE]); > + > + test_result = be32_to_cpup((__be32 *) > + (&buf.data[TPM_HEADER_SIZE + 2 + data_size])); > + > + return test_result; > +} > + > +/** > * tpm2_do_selftest() - ensure that all self tests have passed > * > * @chip: TPM chip to use > @@ -851,10 +895,25 @@ static int tpm2_do_selftest(struct tpm_chip *chip) > "attempting the self test"); > tpm_buf_destroy(&buf); > > + dev_dbg(&chip->dev, "tpm selftest command returned %04x\n", rc); > if (rc == TPM2_RC_TESTING) > rc = TPM2_RC_SUCCESS; > if (rc == TPM2_RC_INITIALIZE || rc == TPM2_RC_SUCCESS) > return rc; > + > + if (rc == TPM2_RC_COMMAND_CODE) { > + > + dev_info(&chip->dev, "Check TPM Test Results\n"); > + rc = tpm2_get_selftest_result(chip); > + > + dev_info(&chip->dev, "tpm self test result is %04x\n", > + rc); > + if (rc == TPM2_RC_TESTING) > + rc = TPM2_RC_SUCCESS; > + if (rc == TPM2_RC_INITIALIZE || rc == TPM2_RC_SUCCESS > + || TPM2_RC_FAILURE) > + return rc; > + } > } > > return rc; > -- > 2.13.6 > The log messages do not have consistent wording and they are prefixed with "tpm" for no reason. I would advice to just remove them. You could probably measure the durations with ftrace by using the function_graph tracer... /Jarkko -- To unsubscribe from this list: send the line "unsubscribe linux-security-module" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h index 82ae7b722161..d95eeb7c002a 100644 --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -107,6 +107,7 @@ enum tpm2_return_codes { TPM2_RC_FAILURE = 0x0101, TPM2_RC_DISABLED = 0x0120, TPM2_RC_COMMAND_CODE = 0x0143, + TPM2_RC_NEEDS_TEST = 0x0153, TPM2_RC_TESTING = 0x090A, /* RC_WARN */ TPM2_RC_REFERENCE_H0 = 0x0910, }; @@ -135,6 +136,7 @@ enum tpm2_command_codes { TPM2_CC_FLUSH_CONTEXT = 0x0165, TPM2_CC_GET_CAPABILITY = 0x017A, TPM2_CC_GET_RANDOM = 0x017B, + TPM2_CC_GET_TEST_RESULT = 0x017C, TPM2_CC_PCR_READ = 0x017E, TPM2_CC_PCR_EXTEND = 0x0182, TPM2_CC_LAST = 0x018F, diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c index 89a5397b18d2..494f6dfbc65d 100644 --- a/drivers/char/tpm/tpm2-cmd.c +++ b/drivers/char/tpm/tpm2-cmd.c @@ -823,6 +823,50 @@ unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal) EXPORT_SYMBOL_GPL(tpm2_calc_ordinal_duration); /** + * tpm2_get_selftest_result() - get the status of self tests + * + * @chip: TPM chip to use + * + * Return: If error return rc, else return the result of the self tests. + * TPM_RC_NEEDS_TESTING: No self tests are done. Needs testing. + * TPM_RC_TESTING: Self tests are in progress. + * TPM_RC_SUCCESS: Self tests completed successfully. + * TPM_RC_FAILURE: Self tests completed failure. + * + * This function can be used to check the status of self tests on the TPM. + */ +static int tpm2_get_selftest_result(struct tpm_chip *chip) +{ + struct tpm_buf buf; + int rc; + int test_result; + uint16_t data_size; + int len; + const struct tpm_output_header *header; + + rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_TEST_RESULT); + if (rc) + return rc; + + len = tpm_transmit(chip, NULL, buf.data, PAGE_SIZE, 0); + if (len < 0) + return len; + + header = (struct tpm_output_header *)buf.data; + + rc = be32_to_cpu(header->return_code); + if (rc) + return rc; + + data_size = be16_to_cpup((__be16 *)&buf.data[TPM_HEADER_SIZE]); + + test_result = be32_to_cpup((__be32 *) + (&buf.data[TPM_HEADER_SIZE + 2 + data_size])); + + return test_result; +} + +/** * tpm2_do_selftest() - ensure that all self tests have passed * * @chip: TPM chip to use @@ -851,10 +895,25 @@ static int tpm2_do_selftest(struct tpm_chip *chip) "attempting the self test"); tpm_buf_destroy(&buf); + dev_dbg(&chip->dev, "tpm selftest command returned %04x\n", rc); if (rc == TPM2_RC_TESTING) rc = TPM2_RC_SUCCESS; if (rc == TPM2_RC_INITIALIZE || rc == TPM2_RC_SUCCESS) return rc; + + if (rc == TPM2_RC_COMMAND_CODE) { + + dev_info(&chip->dev, "Check TPM Test Results\n"); + rc = tpm2_get_selftest_result(chip); + + dev_info(&chip->dev, "tpm self test result is %04x\n", + rc); + if (rc == TPM2_RC_TESTING) + rc = TPM2_RC_SUCCESS; + if (rc == TPM2_RC_INITIALIZE || rc == TPM2_RC_SUCCESS + || TPM2_RC_FAILURE) + return rc; + } } return rc;