efi_loader: Measure the loaded DTB

Measures the DTB passed to the EFI application upon new boolean config
switch CONFIG_EFI_TCG2_PROTOCOL_MEASURE_DTB. For platforms where the
content of the DTB passed to the OS can change across reboots, there is
not point measuring it hence the config switch to allow platform to not
embed this feature.

Co-developed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>
Tested-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
diff --git a/include/efi_loader.h b/include/efi_loader.h
index c664d6c..1542b4b 100644
--- a/include/efi_loader.h
+++ b/include/efi_loader.h
@@ -531,6 +531,8 @@
 efi_status_t efi_tcg2_measure_efi_app_invocation(struct efi_loaded_image_obj *handle);
 /* Measure efi application exit */
 efi_status_t efi_tcg2_measure_efi_app_exit(void);
+/* Measure DTB */
+efi_status_t efi_tcg2_measure_dtb(void *dtb);
 /* Called by bootefi to initialize root node */
 efi_status_t efi_root_node_register(void);
 /* Called by bootefi to initialize runtime */
diff --git a/include/efi_tcg2.h b/include/efi_tcg2.h
index 874306d..b1c3abd 100644
--- a/include/efi_tcg2.h
+++ b/include/efi_tcg2.h
@@ -233,6 +233,16 @@
 	gpt_entry partitions[];
 } __packed;
 
+/**
+ * struct tdUEFI_PLATFORM_FIRMWARE_BLOB2
+ * @blob_description_size:	Byte size of @data
+ * @data:			Description data
+ */
+struct uefi_platform_firmware_blob2 {
+	u8 blob_description_size;
+	u8 data[];
+} __packed;
+
 struct efi_tcg2_protocol {
 	efi_status_t (EFIAPI * get_capability)(struct efi_tcg2_protocol *this,
 					       struct efi_tcg2_boot_service_capability *capability);
diff --git a/include/tpm-v2.h b/include/tpm-v2.h
index 737e575..2df3dad 100644
--- a/include/tpm-v2.h
+++ b/include/tpm-v2.h
@@ -105,6 +105,8 @@
 	"Exit Boot Services Returned with Failure"
 #define EFI_EXIT_BOOT_SERVICES_SUCCEEDED    \
 	"Exit Boot Services Returned with Success"
+#define EFI_DTB_EVENT_STRING \
+	"DTB DATA"
 
 /* TPMS_TAGGED_PROPERTY Structure */
 struct tpms_tagged_property {