diff --git a/src/stkutil.h b/src/stkutil.h
index b3af450c..4add2844 100644
--- a/src/stkutil.h
+++ b/src/stkutil.h
@@ -78,3 +78,100 @@ enum stk_command_type {
 	STK_COMMAND_TYPE_ACTIVATE = 0x70,
 	STK_COMMAND_TYPE_END_SESSION = 0x81,
 };
+
+enum stk_data_object_type {
+	STK_DATA_OBJECT_TYPE_COMMAND_DETAILS = 0x01,
+	STK_DATA_OBJECT_TYPE_DEVICE_IDENTITY = 0x02,
+	STK_DATA_OBJECT_TYPE_RESULT = 0x03,
+	STK_DATA_OBJECT_TYPE_DURATION = 0x04,
+	STK_DATA_OBJECT_TYPE_ALPHA_IDENTIFIER = 0x05,
+	STK_DATA_OBJECT_TYPE_ADDRESS = 0x06,
+	STK_DATA_OBJECT_TYPE_CCP = 0x07,
+	STK_DATA_OBJECT_TYPE_SUBADDRESS = 0x08,
+	STK_DATA_OBJECT_TYPE_SS_STRING = 0x09,
+	STK_DATA_OBJECT_TYPE_USSD_STRING = 0x0A,
+	STK_DATA_OBJECT_TYPE_SMS_TPDU = 0x0B,
+	STK_DATA_OBJECT_TYPE_CBS_PAGE = 0x0C,
+	STK_DATA_OBJECT_TYPE_TEXT = 0x0D,
+	STK_DATA_OBJECT_TYPE_TONE = 0x0E,
+	STK_DATA_OBJECT_TYPE_ITEM = 0x0F,
+	STK_DATA_OBJECT_TYPE_ITEM_ID = 0x10,
+	STK_DATA_OBJECT_TYPE_RESPONSE_LENGTH = 0x11,
+	STK_DATA_OBJECT_TYPE_FILE_LIST = 0x12,
+	STK_DATA_OBJECT_TYPE_LOCATION_INFO = 0x13,
+	STK_DATA_OBJECT_TYPE_IMEI = 0x14,
+	STK_DATA_OBJECT_TYPE_HELP_REQUEST = 0x15,
+	STK_DATA_OBJECT_TYPE_NETWORK_MEASUREMENT_RESULTS = 0x16,
+	STK_DATA_OBJECT_TYPE_DEFAULT_TEXT = 0x17,
+	STK_DATA_OBJECT_TYPE_ITEMS_NEXT_ACTION_INDICATOR = 0x18,
+	STK_DATA_OBJECT_TYPE_EVENT_LIST = 0x19,
+	STK_DATA_OBJECT_TYPE_CAUSE = 0x1A,
+	STK_DATA_OBJECT_TYPE_LOCATION_STATUS = 0x1B,
+	STK_DATA_OBJECT_TYPE_TRANSACTION_ID = 0x1C,
+	STK_DATA_OBJECT_TYPE_ICON_ID = 0x1E,
+	STK_DATA_OBJECT_TYPE_ITEM_ICON_ID_LIST = 0x1F,
+	STK_DATA_OBJECT_TYPE_CARD_READER_STATUS = 0x20,
+	STK_DATA_OBJECT_TYPE_CARD_ATR = 0x21,
+	STK_DATA_OBJECT_TYPE_C_APDU = 0x22,
+	STK_DATA_OBJECT_TYPE_R_APDU = 0x23,
+	STK_DATA_OBJECT_TYPE_TIMER_ID = 0x24,
+	STK_DATA_OBJECT_TYPE_TIMER_VALUE = 0x25,
+	STK_DATA_OBJECT_TYPE_DATETIME_TIMEZONE = 0x26,
+	STK_DATA_OBJECT_TYPE_CALL_CONTROL_REQUESTED_ACTION = 0x27,
+	STK_DATA_OBJECT_TYPE_AT_COMMAND = 0x28,
+	STK_DATA_OBJECT_TYPE_AT_RESPONSE = 0x29,
+	STK_DATA_OBJECT_TYPE_BC_REPEAT_INDICATOR = 0x2A,
+	STK_DATA_OBJECT_TYPE_IMMEDIATE_RESPONSE = 0x2B,
+	STK_DATA_OBJECT_TYPE_DTMF_STRING = 0x2C,
+	STK_DATA_OBJECT_TYPE_LANGUAGE = 0x2D,
+	STK_DATA_OBJECT_TYPE_TIMING_ADVANCE = 0x2E,
+	STK_DATA_OBJECT_TYPE_AID = 0x2F,
+	STK_DATA_OBJECT_TYPE_BROWSER_ID = 0x30,
+	STK_DATA_OBJECT_TYPE_URL = 0x31,
+	STK_DATA_OBJECT_TYPE_BEARER = 0x32,
+	STK_DATA_OBJECT_TYPE_PROVISIONING_REFERENCE_FILE = 0x33,
+	STK_DATA_OBJECT_TYPE_BROWSER_TERMINATION_CAUSE = 0x34,
+	STK_DATA_OBJECT_TYPE_BEARER_DESCRIPTION = 0x35,
+	STK_DATA_OBJECT_TYPE_CHANNEL_DATA = 0x36,
+	STK_DATA_OBJECT_TYPE_CHANNEL_DATA_LENGTH = 0x37,
+	STK_DATA_OBJECT_TYPE_CHANNEL_STATUS = 0x38,
+	STK_DATA_OBJECT_TYPE_BUFFER_SIZE = 0x39,
+	STK_DATA_OBJECT_TYPE_CARD_READER_ID = 0x3A,
+	STK_DATA_OBJECT_TYPE_FILE_UPDATE_INFO = 0x3B,
+	STK_DATA_OBJECT_TYPE_UICC_TE_INTERFACE = 0x3C,
+	STK_DATA_OBJECT_TYPE_OTHER_ADDRESS = 0x3E,
+	STK_DATA_OBJECT_TYPE_ACCESS_TECHNOLOGY = 0x3F,
+	STK_DATA_OBJECT_TYPE_DISPLAY_PARAMETERS = 0x40,
+	STK_DATA_OBJECT_TYPE_SERVICE_RECORD = 0x41,
+	STK_DATA_OBJECT_TYPE_DEVICE_FILTER = 0x42,
+	STK_DATA_OBJECT_TYPE_SERVICE_SEARCH = 0x43,
+	STK_DATA_OBJECT_TYPE_ATTRIBUTE_INFO = 0x44,
+	STK_DATA_OBJECT_TYPE_SERVICE_AVAILABILITY = 0x45,
+	STK_DATA_OBJECT_TYPE_ESN = 0x46,
+	STK_DATA_OBJECT_TYPE_NETWORK_ACCESS_NAME = 0x47,
+	STK_DATA_OBJECT_TYPE_REMOTE_ENTITY_ADDRESS = 0x49,
+	STK_DATA_OBJECT_TYPE_TEXT_ATTRIBUTE = 0x50,
+	STK_DATA_OBJECT_TYPE_ITEM_TEXT_ATTRIBUTE_LIST = 0x51,
+	STK_DATA_OBJECT_TYPE_PDP_ACTIVATION_PARAMETER = 0x52,
+	STK_DATA_OBJECT_TYPE_IMEISV = 0x62,
+	STK_DATA_OBJECT_TYPE_BATTERY_STATE = 0x63,
+	STK_DATA_OBJECT_TYPE_BROWSING_STATUS = 0x64,
+	STK_DATA_OBJECT_TYPE_NETWORK_SEARCH_MODE = 0x65,
+	STK_DATA_OBJECT_TYPE_FRAME_LAYOUT = 0x66,
+	STK_DATA_OBJECT_TYPE_FRAMES_INFO = 0x67,
+	STK_DATA_OBJECT_TYPE_FRAME_ID = 0x68,
+	STK_DATA_OBJECT_TYPE_MMS_REFERENCE = 0x6A,
+	STK_DATA_OBJECT_TYPE_MMS_ID = 0x6B,
+	STK_DATA_OBJECT_TYPE_MMS_TRANSFER_STATUS = 0x6C,
+	STK_DATA_OBJECT_TYPE_MEID = 0x6D,
+	STK_DATA_OBJECT_TYPE_CONTENT_ID = 0x6E,
+	STK_DATA_OBJECT_TYPE_MMS_NOTIFICATION = 0x6F,
+	STK_DATA_OBJECT_TYPE_LAST_ENVELOPE = 0x70,
+	STK_DATA_OBJECT_TYPE_REGISTRY_APPLICATION_DATA = 0x71,
+	STK_DATA_OBJECT_TYPE_ROUTING_AREA_INFO = 0x73,
+	STK_DATA_OBJECT_TYPE_UPDATE_ATTACH_TYPE = 0x74,
+	STK_DATA_OBJECT_TYPE_NMEA_SENTENCE = 0x78,
+	STK_DATA_OBJECT_TYPE_PLMN_LIST = 0x79,
+	STK_DATA_OBJECT_TYPE_BROADCAST_NETWORK_INFO = 0x7A,
+	STK_DATA_OBJECT_TYPE_ACTIVATE_DESCRIPTOR = 0x7B,
+};