[PATCH v3 4/6] tpm: replace TPM algorithms IDs with tpm_pcr_bank_info structs in tpm_chip

From: Roberto Sassu
Date: Wed Jun 21 2017 - 10:34:13 EST


This patch replaces the array of TPM algorithms ID, stored in the tpm_chip
structure, with an array of the new structure tpm_pcr_bank_info.

The array is initialized during the execution of tpm2_get_pcr_allocation(),
by tpm2_init_pcr_bank_info().

tpm2_pcr_extend() and tpm_pcr_extend() have been modified to use the
digest size retrieved from the TPM instead of that from the crypto
subsystem.

Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
---
drivers/char/tpm/tpm-interface.c | 4 ++--
drivers/char/tpm/tpm.h | 2 +-
drivers/char/tpm/tpm2-cmd.c | 22 +++++++++++-----------
3 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index d2b4df6..a11598a 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -897,8 +897,8 @@ int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
memset(digest_list, 0, sizeof(digest_list));

for (i = 0; i < ARRAY_SIZE(chip->active_banks) &&
- chip->active_banks[i] != TPM2_ALG_ERROR; i++) {
- digest_list[i].alg_id = chip->active_banks[i];
+ chip->active_banks[i].alg_id != TPM2_ALG_ERROR; i++) {
+ digest_list[i].alg_id = chip->active_banks[i].alg_id;
memcpy(digest_list[i].digest, hash, TPM_DIGEST_SIZE);
count++;
}
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 62c600d..d285bc6 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -208,7 +208,7 @@ struct tpm_chip {
const struct attribute_group *groups[3];
unsigned int groups_cnt;

- u16 active_banks[7];
+ struct tpm_pcr_bank_info active_banks[7];
#ifdef CONFIG_ACPI
acpi_handle acpi_dev_handle;
char ppi_version[TPM_PPI_VERSION_LEN + 1];
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 74a68ea..7bd2cf7 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -301,7 +301,6 @@ int tpm2_pcr_extend(struct tpm_chip *chip, int pcr_idx, u32 count,
struct tpm2_null_auth_area auth_area;
int rc;
int i;
- int j;

if (count > ARRAY_SIZE(chip->active_banks))
return -EINVAL;
@@ -323,14 +322,10 @@ int tpm2_pcr_extend(struct tpm_chip *chip, int pcr_idx, u32 count,
tpm_buf_append_u32(&buf, count);

for (i = 0; i < count; i++) {
- for (j = 0; j < ARRAY_SIZE(tpm2_hash_map); j++) {
- if (digests[i].alg_id != tpm2_hash_map[j].tpm_id)
- continue;
- tpm_buf_append_u16(&buf, digests[i].alg_id);
- tpm_buf_append(&buf, (const unsigned char
- *)&digests[i].digest,
- hash_digest_size[tpm2_hash_map[j].crypto_id]);
- }
+ /* digests[i].alg_id == chip->active_banks[i].alg_id */
+ tpm_buf_append_u16(&buf, digests[i].alg_id);
+ tpm_buf_append(&buf, (const unsigned char *)&digests[i].digest,
+ chip->active_banks[i].digest_size);
}

rc = tpm_transmit_cmd(chip, NULL, buf.data, PAGE_SIZE, 0, 0,
@@ -1076,7 +1071,12 @@ static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)
}

memcpy(&pcr_selection, marker, sizeof(pcr_selection));
- chip->active_banks[i] = be16_to_cpu(pcr_selection.hash_alg);
+ rc = tpm2_init_pcr_bank_info(chip,
+ be16_to_cpu(pcr_selection.hash_alg),
+ &chip->active_banks[i]);
+ if (rc)
+ break;
+
sizeof_pcr_selection = sizeof(pcr_selection.hash_alg) +
sizeof(pcr_selection.size_of_select) +
pcr_selection.size_of_select;
@@ -1085,7 +1085,7 @@ static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip)

out:
if (i < ARRAY_SIZE(chip->active_banks))
- chip->active_banks[i] = TPM2_ALG_ERROR;
+ chip->active_banks[i].alg_id = TPM2_ALG_ERROR;

tpm_buf_destroy(&buf);

--
2.9.3