ieee1275/tcg2: Refactor grub_ieee1275_tpm_init()

Move tpm_get_tpm_version() into grub_ieee1275_tpm_init() and invalidate
grub_ieee1275_tpm_ihandle in case no TPM 2 could be detected. Try the
initialization only once so that grub_tpm_present() will always return
the same result. Use the grub_ieee1275_tpm_ihandle as indicator for an
available TPM instead of grub_ieee1275_tpm_version, which can now be
removed.

Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
This commit is contained in:
Stefan Berger 2024-11-26 15:39:44 -05:00 committed by Daniel Kiper
parent 8c0b5f2003
commit 72092a8641
3 changed files with 18 additions and 25 deletions

View File

@ -100,7 +100,7 @@ grub_tpm_measure (unsigned char *buf, grub_size_t size, grub_uint8_t pcr,
grub_dprintf ("tpm", "log_event, pcr = %d, size = 0x%" PRIxGRUB_SIZE ", %s\n",
pcr, size, description);
if (grub_ieee1275_tpm_version == 2)
if (grub_ieee1275_tpm_ihandle != GRUB_IEEE1275_IHANDLE_INVALID)
return tpm2_log_event (buf, size, pcr, description);
return GRUB_ERR_NONE;

View File

@ -23,39 +23,33 @@
#include <grub/mm.h>
#include <grub/misc.h>
grub_ieee1275_ihandle_t grub_ieee1275_tpm_ihandle;
grub_uint8_t grub_ieee1275_tpm_version;
static void
tpm_get_tpm_version (void)
{
grub_ieee1275_phandle_t vtpm;
char buffer[20];
if (!grub_ieee1275_finddevice ("/vdevice/vtpm", &vtpm) &&
!grub_ieee1275_get_property (vtpm, "compatible", buffer,
sizeof (buffer), NULL) &&
!grub_strcmp (buffer, "IBM,vtpm20"))
grub_ieee1275_tpm_version = 2;
}
grub_ieee1275_ihandle_t grub_ieee1275_tpm_ihandle = GRUB_IEEE1275_IHANDLE_INVALID;
grub_err_t
grub_ieee1275_tpm_init (void)
{
static int init_success = 0;
static bool init_tried = false;
grub_ieee1275_phandle_t vtpm;
char buffer[20];
if (!init_success)
if (init_tried == false)
{
if (grub_ieee1275_open ("/vdevice/vtpm", &grub_ieee1275_tpm_ihandle) < 0)
init_tried = true;
if (grub_ieee1275_open ("/vdevice/vtpm", &grub_ieee1275_tpm_ihandle) < 0 ||
grub_ieee1275_finddevice ("/vdevice/vtpm", &vtpm) ||
grub_ieee1275_get_property (vtpm, "compatible", buffer, sizeof (buffer), NULL) ||
grub_strcmp (buffer, "IBM,vtpm20"))
{
if (grub_ieee1275_tpm_ihandle != GRUB_IEEE1275_IHANDLE_INVALID)
grub_ieee1275_close (grub_ieee1275_tpm_ihandle);
grub_ieee1275_tpm_ihandle = GRUB_IEEE1275_IHANDLE_INVALID;
return GRUB_ERR_UNKNOWN_DEVICE;
}
init_success = 1;
tpm_get_tpm_version ();
}
if (grub_ieee1275_tpm_ihandle == GRUB_IEEE1275_IHANDLE_INVALID)
return GRUB_ERR_UNKNOWN_DEVICE;
return GRUB_ERR_NONE;
}

View File

@ -24,7 +24,6 @@
#include <grub/ieee1275/ieee1275.h>
extern grub_ieee1275_ihandle_t grub_ieee1275_tpm_ihandle;
extern grub_uint8_t grub_ieee1275_tpm_version;
extern grub_err_t grub_ieee1275_tpm_init (void);