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tpm: factor out tpm1_get_random into tpm1-cmd.c

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Factor out get random implementation from tpm-interface.c
into tpm1_get_random function in tpm1-cmd.c.
No functional changes.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
This commit is contained in:
Tomas Winkler 2018-10-19 21:22:55 +03:00 committed by Jarkko Sakkinen
parent f4d916b72f
commit 433d390f00
3 changed files with 63 additions and 51 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

58
drivers/char/tpm/tpm-interface.c
View File

@ -811,14 +811,6 @@ int tpm_pm_resume(struct device *dev)
}
EXPORT_SYMBOL_GPL(tpm_pm_resume);
#define TPM_ORD_GET_RANDOM 70
#define TPM_GETRANDOM_RESULT_SIZE 18
static const struct tpm_input_header tpm_getrandom_header = {
.tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
.length = cpu_to_be32(14),
.ordinal = cpu_to_be32(TPM_ORD_GET_RANDOM)
};
/**
* tpm_get_random() - get random bytes from the TPM's RNG
* @chip: a &struct tpm_chip instance, %NULL for the default chip
@ -829,58 +821,22 @@ static const struct tpm_input_header tpm_getrandom_header = {
*/
int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max)
{
struct tpm_cmd_t tpm_cmd;
u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA), rlength;
int err, total = 0, retries = 5;
u8 *dest = out;
int rc;
if (!out || !num_bytes || max > TPM_MAX_RNG_DATA)
if (!out || max > TPM_MAX_RNG_DATA)
return -EINVAL;
chip = tpm_find_get_ops(chip);
if (!chip)
return -ENODEV;
if (chip->flags & TPM_CHIP_FLAG_TPM2) {
err = tpm2_get_random(chip, out, max);
tpm_put_ops(chip);
return err;
}
do {
tpm_cmd.header.in = tpm_getrandom_header;
tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes);
err = tpm_transmit_cmd(chip, NULL, &tpm_cmd,
TPM_GETRANDOM_RESULT_SIZE + num_bytes,
offsetof(struct tpm_getrandom_out,
rng_data),
0, "attempting get random");
if (err)
break;
recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len);
if (recd > num_bytes) {
total = -EFAULT;
break;
}
rlength = be32_to_cpu(tpm_cmd.header.out.length);
if (rlength < TPM_HEADER_SIZE +
offsetof(struct tpm_getrandom_out, rng_data) +
recd) {
total = -EFAULT;
break;
}
memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd);
dest += recd;
total += recd;
num_bytes -= recd;
} while (retries-- && total < max);
if (chip->flags & TPM_CHIP_FLAG_TPM2)
rc = tpm2_get_random(chip, out, max);
else
rc = tpm1_get_random(chip, out, max);
tpm_put_ops(chip);
return total ? total : -EIO;
return rc;
}
EXPORT_SYMBOL_GPL(tpm_get_random);

1
drivers/char/tpm/tpm.h
View File

@ -551,6 +551,7 @@ int tpm1_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash,
const char *log_msg);
ssize_t tpm1_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap,
const char *desc, size_t min_cap_length);
int tpm1_get_random(struct tpm_chip *chip, u8 *out, size_t max);
unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal);
int tpm_pm_suspend(struct device *dev);
int tpm_pm_resume(struct device *dev);

55
drivers/char/tpm/tpm1-cmd.c
View File

@ -469,3 +469,58 @@ ssize_t tpm1_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap,
return rc;
}
EXPORT_SYMBOL_GPL(tpm1_getcap);
#define TPM_ORD_GET_RANDOM 70
#define TPM_GETRANDOM_RESULT_SIZE 18
static const struct tpm_input_header tpm_getrandom_header = {
.tag = cpu_to_be16(TPM_TAG_RQU_COMMAND),
.length = cpu_to_be32(14),
.ordinal = cpu_to_be32(TPM_ORD_GET_RANDOM)
};
int tpm1_get_random(struct tpm_chip *chip, u8 *out, size_t max)
{
struct tpm_cmd_t tpm_cmd;
u32 recd;
u32 num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA);
u32 rlength;
int err, total = 0, retries = 5;
u8 *dest = out;
if (!out || !num_bytes || max > TPM_MAX_RNG_DATA)
return -EINVAL;
do {
tpm_cmd.header.in = tpm_getrandom_header;
tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes);
err = tpm_transmit_cmd(chip, NULL, &tpm_cmd,
TPM_GETRANDOM_RESULT_SIZE + num_bytes,
offsetof(struct tpm_getrandom_out,
rng_data),
0, "attempting get random");
if (err)
break;
recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len);
if (recd > num_bytes) {
total = -EFAULT;
break;
}
rlength = be32_to_cpu(tpm_cmd.header.out.length);
if (rlength < TPM_HEADER_SIZE +
offsetof(struct tpm_getrandom_out, rng_data) +
recd) {
total = -EFAULT;
break;
}
memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd);
dest += recd;
total += recd;
num_bytes -= recd;
} while (retries-- && (size_t)total < max);
return total ? total : -EIO;
}