summaryrefslogtreecommitdiff
path: root/src/shared/efivars.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/shared/efivars.c')
-rw-r--r--src/shared/efivars.c72
1 files changed, 72 insertions, 0 deletions
diff --git a/src/shared/efivars.c b/src/shared/efivars.c
index 20067c601a..b82f74a459 100644
--- a/src/shared/efivars.c
+++ b/src/shared/efivars.c
@@ -25,6 +25,7 @@
#include "util.h"
#include "utf8.h"
+#include "virt.h"
#include "efivars.h"
#ifdef ENABLE_EFI
@@ -37,6 +38,7 @@
#define MBR_TYPE_EFI_PARTITION_TABLE_HEADER 0x02
#define END_DEVICE_PATH_TYPE 0x7f
#define END_ENTIRE_DEVICE_PATH_SUBTYPE 0xff
+#define EFI_OS_INDICATIONS_BOOT_TO_FW_UI 0x0000000000000001
struct boot_option {
uint32_t attr;
@@ -93,6 +95,76 @@ int is_efi_secure_boot_setup_mode(void) {
return read_flag("SetupMode");
}
+int efi_reboot_to_firmware_supported(void) {
+ int r;
+ size_t s;
+ uint64_t b;
+ _cleanup_free_ void *v = NULL;
+
+ if (!is_efi_boot() || detect_container(NULL) > 0)
+ return -EOPNOTSUPP;
+
+ r = efi_get_variable(EFI_VENDOR_GLOBAL, "OsIndicationsSupported", NULL, &v, &s);
+ if (r < 0)
+ return r;
+ else if (s != sizeof(uint64_t))
+ return -EINVAL;
+
+ b = *(uint64_t *)v;
+ b &= EFI_OS_INDICATIONS_BOOT_TO_FW_UI;
+ return b > 0 ? 0 : -EOPNOTSUPP;
+}
+
+static int get_os_indications(uint64_t *os_indication) {
+ int r;
+ size_t s;
+ _cleanup_free_ void *v = NULL;
+
+ r = efi_reboot_to_firmware_supported();
+ if (r < 0)
+ return r;
+
+ r = efi_get_variable(EFI_VENDOR_GLOBAL, "OsIndications", NULL, &v, &s);
+ if (r < 0)
+ return r;
+ else if (s != sizeof(uint64_t))
+ return -EINVAL;
+
+ *os_indication = *(uint64_t *)v;
+ return 0;
+}
+
+int efi_get_reboot_to_firmware(void) {
+ int r;
+ uint64_t b;
+
+ r = get_os_indications(&b);
+ if (r < 0)
+ return r;
+
+ return !!(b & EFI_OS_INDICATIONS_BOOT_TO_FW_UI);
+}
+
+int efi_set_reboot_to_firmware(bool value) {
+ int r;
+ uint64_t b, b_new;
+
+ r = get_os_indications(&b);
+ if (r < 0)
+ return r;
+
+ if (value)
+ b_new = b | EFI_OS_INDICATIONS_BOOT_TO_FW_UI;
+ else
+ b_new = b & ~EFI_OS_INDICATIONS_BOOT_TO_FW_UI;
+
+ /* Avoid writing to efi vars store if we can due to firmware bugs. */
+ if (b != b_new)
+ return efi_set_variable(EFI_VENDOR_GLOBAL, "OsIndications", &b_new, sizeof(uint64_t));
+
+ return 0;
+}
+
int efi_get_variable(
sd_id128_t vendor,
const char *name,