/*Ignore PCR on TPM 2.0, read PCR values for TPM 1.x seal | unseal*/
void TPM_read_pcrs(void)
{
int i;
for (i=0; i < 24; i++) {
if (hw_is_tpm2())
tpm2_pcr_read(i, (uint8_t *)&hwtpm.pcrs[i]);
else
TPM_PCR_Read(i, &hwtpm.pcrs[i]);
}
}
/**
* tpm_pcr_read - read a pcr value
* @chip_num: tpm idx # or ANY
* @pcr_idx: pcr idx to retrieve
* @res_buf: TPM_PCR value
* size of res_buf is 20 bytes (or NULL if you don't care)
*
* The TPM driver should be built-in, but for whatever reason it
* isn't, protect against the chip disappearing, by incrementing
* the module usage count.
*/
int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
{
struct tpm_chip *chip;
int rc;
chip = tpm_chip_find_get(chip_num);
if (chip == NULL)
return -ENODEV;
if (chip->flags & TPM_CHIP_FLAG_TPM2)
rc = tpm2_pcr_read(chip, pcr_idx, res_buf);
else
rc = tpm_pcr_read_dev(chip, pcr_idx, res_buf);
tpm_put_ops(chip);
return rc;
}
/**
* 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;
}
