On Wed, Jan 18, 2017 at 03:44:49AM -0500, Nayna Jain wrote: > This patch implements the TPM 2.0 capability TPM_CAP_PCRS to > retrieve the active PCR banks from the TPM. This is needed > to enable extending all active banks as recommended by TPM 2.0 > TCG Specification. > > Signed-off-by: Nayna Jain <na...@linux.vnet.ibm.com> > --- > drivers/char/tpm/tpm.h | 4 ++++ > drivers/char/tpm/tpm2-cmd.c | 57 > +++++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 61 insertions(+) > > diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h > index 1ae9768..dddd573 100644 > --- a/drivers/char/tpm/tpm.h > +++ b/drivers/char/tpm/tpm.h > @@ -127,6 +127,7 @@ enum tpm2_permanent_handles { > }; > > enum tpm2_capabilities { > + TPM2_CAP_PCRS = 5, > TPM2_CAP_TPM_PROPERTIES = 6, > }; > > @@ -187,6 +188,8 @@ struct tpm_chip { > > const struct attribute_group *groups[3]; > unsigned int groups_cnt; > + > + u16 active_banks[7]; > #ifdef CONFIG_ACPI > acpi_handle acpi_dev_handle; > char ppi_version[TPM_PPI_VERSION_LEN + 1]; > @@ -545,4 +548,5 @@ int tpm2_auto_startup(struct tpm_chip *chip); > void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type); > unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal); > int tpm2_probe(struct tpm_chip *chip); > +ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip); > #endif > diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c > index 6eda239..75a7546 100644 > --- a/drivers/char/tpm/tpm2-cmd.c > +++ b/drivers/char/tpm/tpm2-cmd.c > @@ -998,3 +998,60 @@ int tpm2_auto_startup(struct tpm_chip *chip) > rc = -ENODEV; > return rc; > } > + > +struct tpm2_pcr_selection { > + __be16 hash_alg; > + u8 size_of_select; > + u8 pcr_select[3]; > +} __packed; > + > +/** > + * tpm2_get_pcr_allocation() - get TPM active PCR banks. > + * > + * @chip: TPM chip to use. > + * > + * Return: Same as with tpm_transmit_cmd. > + */ > +ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip) > +{ > + struct tpm2_pcr_selection pcr_selection; > + struct tpm_buf buf; > + void *marker; > + unsigned int count = 0;
You shouldn't initialize 'count'. > + int rc; > + int i; > + > + rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY); > + if (rc) > + return rc; > + > + tpm_buf_append_u32(&buf, TPM2_CAP_PCRS); > + tpm_buf_append_u32(&buf, 0); > + tpm_buf_append_u32(&buf, 1); > + > + rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, 0, > + "get tpm pcr allocation"); > + if (rc < 0) > + goto out; > + > + count = be32_to_cpup( > + (__be32 *)&buf.data[TPM_HEADER_SIZE + 5]); > + > + if (count > ARRAY_SIZE(chip->active_banks)) > + return -ENODEV; > + > + marker = &buf.data[TPM_HEADER_SIZE + 9]; > + for (i = 0; i < count; i++) { > + memcpy(&pcr_selection, marker, sizeof(pcr_selection)); > + chip->active_banks[i] = be16_to_cpu(pcr_selection.hash_alg); > + marker = marker + sizeof(struct tpm2_pcr_selection); > + } > + > +out: > + if (count < ARRAY_SIZE(chip->active_banks)) > + chip->active_banks[count] = 0; > + > + tpm_buf_destroy(&buf); > + > + return rc; > +} > -- > 2.5.0 Otherwise, Reviewed-by: Jarkko Sakkinen <jarkko.sakk...@linux.intel.com> /Jarkko ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ tpmdd-devel mailing list tpmdd-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/tpmdd-devel