static ssize_t pcrs_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
cap_t cap;
u8 digest[TPM_DIGEST_SIZE];
ssize_t rc;
u32 i, j, num_pcrs;
char *str = buf;
struct tpm_chip *chip = to_tpm_chip(dev);
rc = tpm1_getcap(chip, TPM_CAP_PROP_PCR, &cap,
"attempting to determine the number of PCRS",
sizeof(cap.num_pcrs));
if (rc)
return 0;
num_pcrs = be32_to_cpu(cap.num_pcrs);
for (i = 0; i < num_pcrs; i++) {
rc = tpm1_pcr_read(chip, i, digest);
if (rc)
break;
str += sprintf(str, "PCR-%02d: ", i);
for (j = 0; j < TPM_DIGEST_SIZE; j++)
str += sprintf(str, "%02X ", digest[j]);
str += sprintf(str, "\n");
}
return str - buf;
}
/**
* tpm_pcr_read - read a PCR value from SHA1 bank
* @chip: a &struct tpm_chip instance, %NULL for the default chip
* @pcr_idx: the PCR to be retrieved
* @digest: the PCR bank and buffer current PCR value is written to
*
* Return: same as with tpm_transmit_cmd()
*/
int tpm_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
struct tpm_digest *digest)
{
int rc;
chip = tpm_find_get_ops(chip);
if (!chip)
return -ENODEV;
if (chip->flags & TPM_CHIP_FLAG_TPM2)
rc = tpm2_pcr_read(chip, pcr_idx, digest, NULL);
else
rc = tpm1_pcr_read(chip, pcr_idx, digest->digest);
tpm_put_ops(chip);
return rc;
}
