forked from luck/tmp_suning_uos_patched
TPM: workaround to enforce PCR updates across suspends
Add a workaround for TPM's which fail to flush last written PCR values in a TPM_SaveState, in preparation for suspend. Signed-off-by: David Safford <safford@watson.ibm.com> Acked-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
This commit is contained in:
parent
310de047ee
commit
225a9be24d
@ -99,6 +99,7 @@ parameter is applicable:
|
||||
SWSUSP Software suspend (hibernation) is enabled.
|
||||
SUSPEND System suspend states are enabled.
|
||||
FTRACE Function tracing enabled.
|
||||
TPM TPM drivers are enabled.
|
||||
TS Appropriate touchscreen support is enabled.
|
||||
UMS USB Mass Storage support is enabled.
|
||||
USB USB support is enabled.
|
||||
@ -2619,6 +2620,15 @@ and is between 256 and 4096 characters. It is defined in the file
|
||||
|
||||
tp720= [HW,PS2]
|
||||
|
||||
tpm_suspend_pcr=[HW,TPM]
|
||||
Format: integer pcr id
|
||||
Specify that at suspend time, the tpm driver
|
||||
should extend the specified pcr with zeros,
|
||||
as a workaround for some chips which fail to
|
||||
flush the last written pcr on TPM_SaveState.
|
||||
This will guarantee that all the other pcrs
|
||||
are saved.
|
||||
|
||||
trace_buf_size=nn[KMG]
|
||||
[FTRACE] will set tracing buffer size.
|
||||
|
||||
|
@ -1067,6 +1067,27 @@ void tpm_remove_hardware(struct device *dev)
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(tpm_remove_hardware);
|
||||
|
||||
#define TPM_ORD_SAVESTATE cpu_to_be32(152)
|
||||
#define SAVESTATE_RESULT_SIZE 10
|
||||
|
||||
static struct tpm_input_header savestate_header = {
|
||||
.tag = TPM_TAG_RQU_COMMAND,
|
||||
.length = cpu_to_be32(10),
|
||||
.ordinal = TPM_ORD_SAVESTATE
|
||||
};
|
||||
|
||||
/* Bug workaround - some TPM's don't flush the most
|
||||
* recently changed pcr on suspend, so force the flush
|
||||
* with an extend to the selected _unused_ non-volatile pcr.
|
||||
*/
|
||||
static int tpm_suspend_pcr;
|
||||
static int __init tpm_suspend_setup(char *str)
|
||||
{
|
||||
get_option(&str, &tpm_suspend_pcr);
|
||||
return 1;
|
||||
}
|
||||
__setup("tpm_suspend_pcr=", tpm_suspend_setup);
|
||||
|
||||
/*
|
||||
* We are about to suspend. Save the TPM state
|
||||
* so that it can be restored.
|
||||
@ -1074,17 +1095,29 @@ EXPORT_SYMBOL_GPL(tpm_remove_hardware);
|
||||
int tpm_pm_suspend(struct device *dev, pm_message_t pm_state)
|
||||
{
|
||||
struct tpm_chip *chip = dev_get_drvdata(dev);
|
||||
u8 savestate[] = {
|
||||
0, 193, /* TPM_TAG_RQU_COMMAND */
|
||||
0, 0, 0, 10, /* blob length (in bytes) */
|
||||
0, 0, 0, 152 /* TPM_ORD_SaveState */
|
||||
};
|
||||
struct tpm_cmd_t cmd;
|
||||
int rc;
|
||||
|
||||
u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
|
||||
|
||||
if (chip == NULL)
|
||||
return -ENODEV;
|
||||
|
||||
tpm_transmit(chip, savestate, sizeof(savestate));
|
||||
return 0;
|
||||
/* for buggy tpm, flush pcrs with extend to selected dummy */
|
||||
if (tpm_suspend_pcr) {
|
||||
cmd.header.in = pcrextend_header;
|
||||
cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
|
||||
memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
|
||||
TPM_DIGEST_SIZE);
|
||||
rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
|
||||
"extending dummy pcr before suspend");
|
||||
}
|
||||
|
||||
/* now do the actual savestate */
|
||||
cmd.header.in = savestate_header;
|
||||
rc = transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE,
|
||||
"sending savestate before suspend");
|
||||
return rc;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(tpm_pm_suspend);
|
||||
|
||||
|
Loading…
Reference in New Issue
Block a user