efi_loader: add ExitBootServices() measurement

TCG PC Client PFP spec requires to measure
"Exit Boot Services Invocation" if ExitBootServices() is invoked.
Depending upon the return code from the ExitBootServices() call,
"Exit Boot Services Returned with Success" or "Exit Boot Services
Returned with Failure" is also measured.

Signed-off-by: Masahisa Kojima <masahisa.kojima@linaro.org>

Swap two ifs in efi_exit_boot_services().
efi_tcg2_notify_exit_boot_services must have EFIAPI signature.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
diff --git a/lib/efi_loader/efi_tcg2.c b/lib/efi_loader/efi_tcg2.c
index ed71337..c6f2e48 100644
--- a/lib/efi_loader/efi_tcg2.c
+++ b/lib/efi_loader/efi_tcg2.c
@@ -1507,6 +1507,67 @@
 }
 
 /**
+ * efi_tcg2_notify_exit_boot_services() - ExitBootService callback
+ *
+ * @event:	callback event
+ * @context:	callback context
+ */
+static void EFIAPI
+efi_tcg2_notify_exit_boot_services(struct efi_event *event, void *context)
+{
+	efi_status_t ret;
+	struct udevice *dev;
+
+	EFI_ENTRY("%p, %p", event, context);
+
+	ret = platform_get_tpm2_device(&dev);
+	if (ret != EFI_SUCCESS)
+		goto out;
+
+	ret = tcg2_measure_event(dev, 5, EV_EFI_ACTION,
+				 strlen(EFI_EXIT_BOOT_SERVICES_INVOCATION),
+				 (u8 *)EFI_EXIT_BOOT_SERVICES_INVOCATION);
+	if (ret != EFI_SUCCESS)
+		goto out;
+
+	ret = tcg2_measure_event(dev, 5, EV_EFI_ACTION,
+				 strlen(EFI_EXIT_BOOT_SERVICES_SUCCEEDED),
+				 (u8 *)EFI_EXIT_BOOT_SERVICES_SUCCEEDED);
+
+out:
+	EFI_EXIT(ret);
+}
+
+/**
+ * efi_tcg2_notify_exit_boot_services_failed()
+ *  - notify ExitBootServices() is failed
+ *
+ * Return:	status code
+ */
+efi_status_t efi_tcg2_notify_exit_boot_services_failed(void)
+{
+	struct udevice *dev;
+	efi_status_t ret;
+
+	ret = platform_get_tpm2_device(&dev);
+	if (ret != EFI_SUCCESS)
+		goto out;
+
+	ret = tcg2_measure_event(dev, 5, EV_EFI_ACTION,
+				 strlen(EFI_EXIT_BOOT_SERVICES_INVOCATION),
+				 (u8 *)EFI_EXIT_BOOT_SERVICES_INVOCATION);
+	if (ret != EFI_SUCCESS)
+		goto out;
+
+	ret = tcg2_measure_event(dev, 5, EV_EFI_ACTION,
+				 strlen(EFI_EXIT_BOOT_SERVICES_FAILED),
+				 (u8 *)EFI_EXIT_BOOT_SERVICES_FAILED);
+
+out:
+	return ret;
+}
+
+/**
  * tcg2_measure_secure_boot_variable() - measure secure boot variables
  *
  * @dev:	TPM device
@@ -1584,6 +1645,7 @@
 {
 	efi_status_t ret = EFI_SUCCESS;
 	struct udevice *dev;
+	struct efi_event *event;
 
 	ret = platform_get_tpm2_device(&dev);
 	if (ret != EFI_SUCCESS) {
@@ -1608,6 +1670,14 @@
 		goto fail;
 	}
 
+	ret = efi_create_event(EVT_SIGNAL_EXIT_BOOT_SERVICES, TPL_CALLBACK,
+			       efi_tcg2_notify_exit_boot_services, NULL,
+			       NULL, &event);
+	if (ret != EFI_SUCCESS) {
+		tcg2_uninit();
+		goto fail;
+	}
+
 	ret = tcg2_measure_secure_boot_variable(dev);
 	if (ret != EFI_SUCCESS) {
 		tcg2_uninit();