1267 lines
59 KiB
C
1267 lines
59 KiB
C
/* packet-mbtcp.c
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* Routines for Modbus/TCP and Modbus/UDP dissection
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* By Riaan Swart <rswart@cs.sun.ac.za>
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* Copyright 2001, Institute for Applied Computer Science
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* University of Stellenbosch
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*
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* See
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*
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* http://www.modbus.org/
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*
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* for information on Modbus/TCP.
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*
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* Updated to v1.1b of the Modbus Application Protocol specification
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* Michael Mann * Copyright 2011
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*
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* $Id$
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*
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* Wireshark - Network traffic analyzer
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* By Gerald Combs <gerald@wireshark.org>
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* Copyright 1998 Gerald Combs
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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*/
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#include "config.h"
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#include <epan/packet.h>
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#include "packet-tcp.h"
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#include "packet-mbtcp.h"
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/* Initialize the protocol and registered fields */
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static int proto_mbtcp = -1;
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static int proto_modbus = -1;
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static int hf_mbtcp_transid = -1;
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static int hf_mbtcp_protid = -1;
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static int hf_mbtcp_len = -1;
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static int hf_mbtcp_unitid = -1;
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static int hf_mbtcp_functioncode = -1;
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static int hf_modbus_reference = -1;
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static int hf_modbus_lreference = -1;
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static int hf_modbus_reftype = -1;
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static int hf_modbus_readref = -1;
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static int hf_modbus_writeref = -1;
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static int hf_modbus_wordcnt = -1;
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static int hf_modbus_readwordcnt = -1;
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static int hf_modbus_writewordcnt = -1;
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static int hf_modbus_bytecnt = -1;
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static int hf_modbus_lbytecnt = -1;
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static int hf_modbus_bitcnt = -1;
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static int hf_modbus_exceptioncode = -1;
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static int hf_modbus_diag_sf = -1;
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static int hf_modbus_status = -1;
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static int hf_modbus_event_count = -1;
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static int hf_modbus_message_count = -1;
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static int hf_modbus_event_recv_comm_err = -1;
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static int hf_modbus_event_recv_char_over = -1;
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static int hf_modbus_event_recv_lo_mode = -1;
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static int hf_modbus_event_recv_broadcast = -1;
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static int hf_modbus_event_send_read_ex = -1;
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static int hf_modbus_event_send_slave_abort_ex = -1;
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static int hf_modbus_event_send_slave_busy_ex = -1;
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static int hf_modbus_event_send_slave_nak_ex = -1;
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static int hf_modbus_event_send_write_timeout = -1;
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static int hf_modbus_event_send_lo_mode = -1;
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static int hf_modbus_andmask = -1;
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static int hf_modbus_ormask = -1;
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static int hf_modbus_data = -1;
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static int hf_modbus_mei = -1;
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static int hf_modbus_read_device_id = -1;
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static int hf_modbus_object_id = -1;
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static int hf_modbus_num_objects = -1;
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static int hf_modbus_list_object_len = -1;
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static int hf_modbus_conformity_level = -1;
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static int hf_modbus_more_follows = -1;
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static int hf_modbus_next_object_id = -1;
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static int hf_modbus_object_str_value = -1;
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/* Initialize the subtree pointers */
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static gint ett_mbtcp = -1;
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static gint ett_modbus_hdr = -1;
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static gint ett_group_hdr = -1;
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static gint ett_events = -1;
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static gint ett_events_recv = -1;
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static gint ett_events_send = -1;
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static gint ett_device_id_objects = -1;
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static gint ett_device_id_object_items = -1;
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static dissector_table_t mbtcp_dissector_table;
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static dissector_table_t modbus_dissector_table;
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static dissector_handle_t modbus_handle;
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static gboolean mbtcp_desegment = TRUE;
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static int
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classify_packet(packet_info *pinfo)
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{
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/* see if nature of packets can be derived from src/dst ports */
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/* if so, return as found */
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if (( pinfo->srcport == PORT_MBTCP ) && ( pinfo->destport != PORT_MBTCP ))
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return RESPONSE_PACKET;
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if (( pinfo->srcport != PORT_MBTCP ) && ( pinfo->destport == PORT_MBTCP ))
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return QUERY_PACKET;
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/* else, cannot classify */
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return CANNOT_CLASSIFY;
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}
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/* Translate function to string, as given on p6 of
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* "Open Modbus/TCP Specification", release 1 by Andy Swales.
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*/
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static const value_string function_code_vals[] = {
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{ READ_COILS, "Read coils" },
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{ READ_INPUT_DISCRETES, "Read input discretes" },
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{ READ_MULT_REGS, "Read multiple registers" },
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{ READ_INPUT_REGS, "Read input registers" },
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{ WRITE_COIL, "Write coil" },
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{ WRITE_SINGLE_REG, "Write single register" },
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{ READ_EXCEPT_STAT, "Read exception status" },
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{ DIAGNOSTICS, "Diagnostics" },
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{ GET_COMM_EVENT_CTRS, "Get Comm. Event Counters" },
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{ GET_COMM_EVENT_LOG, "Get Comm. Event Log" },
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{ WRITE_MULT_COILS, "Write Multiple Coils" },
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{ WRITE_MULT_REGS, "Write Multiple Registers" },
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{ REPORT_SLAVE_ID, "Report Slave ID" },
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{ READ_FILE_RECORD, "Read File Record" },
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{ WRITE_FILE_RECORD, "Write File Record" },
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{ MASK_WRITE_REG, "Mask Write Register" },
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{ READ_WRITE_REG, "Read Write Register" },
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{ READ_FIFO_QUEUE, "Read FIFO Queue" },
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{ ENCAP_INTERFACE_TRANSP, "Encapsulated Interface Transport" },
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{ 0, NULL }
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};
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/* Translate exception code to string */
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static const value_string exception_code_vals[] = {
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{ ILLEGAL_FUNCTION, "Illegal function" },
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{ ILLEGAL_ADDRESS, "Illegal data address" },
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{ ILLEGAL_VALUE, "Illegal data value" },
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{ SLAVE_FAILURE, "Slave device failure" },
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{ ACKNOWLEDGE, "Acknowledge" },
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{ SLAVE_BUSY, "Slave device busy" },
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{ MEMORY_ERR, "Memory parity error" },
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{ GATEWAY_UNAVAILABLE, "Gateway path unavailable" },
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{ GATEWAY_TRGT_FAIL, "Gateway target device failed to respond" },
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{ 0, NULL }
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};
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/* Translate Modbus Encapsulation Interface (MEI) code to string */
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static const value_string encap_interface_code_vals[] = {
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{ CANOPEN_REQ_RESP, "CANopen Request/Response " },
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{ READ_DEVICE_ID, "Read Device Identification" },
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{ 0, NULL }
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};
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/* Translate Modbus Diagnostic subfunction code to string */
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static const value_string diagnostic_code_vals[] = {
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{ RETURN_QUERY_DATA, "Return Query Data" },
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{ RESTART_COMMUNICATION_OPTION, "Restart Communications Option" },
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{ RETURN_DIAGNOSTIC_REGISTER, "Return Diagnostic Register" },
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{ CHANGE_ASCII_INPUT_DELIMITER, "Change ASCII Input Delimiter" },
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{ FORCE_LISTEN_ONLY_MODE, "Force Listen Only Mode" },
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{ CLEAR_COUNTERS_AND_DIAG_REG, "Clear Counters and Diagnostic Register" },
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{ RETURN_BUS_MESSAGE_COUNT, "Return Bus Message Count" },
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{ RETURN_BUS_COMM_ERROR_COUNT, "Return Bus Communication Error Count" },
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{ RETURN_BUS_EXCEPTION_ERROR_COUNT, "Return Bus Exception Error Count" },
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{ RETURN_SLAVE_MESSAGE_COUNT, "Return Slave Message Count" },
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{ RETURN_SLAVE_NO_RESPONSE_COUNT, "Return Slave No Response Count" },
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{ RETURN_SLAVE_NAK_COUNT, "Return Slave NAK Count" },
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{ RETURN_SLAVE_BUSY_COUNT, "Return Slave Busy Count" },
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{ RETURN_BUS_CHAR_OVERRUN_COUNT, "Return Bus Character Overrun Count" },
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{ CLEAR_OVERRUN_COUNTER_AND_FLAG, "Clear Overrun Counter and Flag" },
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{ 0, NULL }
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};
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/* Translate read device code to string */
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static const value_string read_device_id_vals[] = {
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{ 1, "Basic Device Identification" },
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{ 2, "Regular Device Identification" },
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{ 3, "Extended Device Identification" },
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{ 4, "Specific Identification Object" },
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{ 0, NULL }
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};
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/* Translate read device code to string */
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static const value_string object_id_vals[] = {
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{ 0, "VendorName" },
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{ 1, "ProductCode" },
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{ 2, "MajorMinorRevision" },
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{ 3, "VendorURL" },
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{ 4, "ProductName" },
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{ 5, "ModelName" },
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{ 6, "UserApplicationName" },
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{ 0, NULL }
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};
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static const value_string conformity_level_vals[] = {
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{ 0x01, "Basic Device Identification (stream)" },
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{ 0x02, "Regular Device Identification (stream)" },
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{ 0x03, "Extended Device Identification (stream)" },
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{ 0x81, "Basic Device Identification (stream and individual)" },
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{ 0x82, "Regular Device Identification (stream and individual)" },
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{ 0x83, "Extended Device Identification (stream and individual)" },
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{ 0, NULL }
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};
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/* Code to actually dissect the packets */
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static void
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dissect_mbtcp_pdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
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{
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/* Set up structures needed to add the protocol subtree and manage it */
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proto_item *mi;
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proto_tree *mbtcp_tree;
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int offset, packet_type;
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tvbuff_t *next_tvb;
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const char *func_string = "";
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const char *pkt_type_str = "";
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const char *err_str = "";
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guint16 transaction_id, protocol_id, len;
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guint8 unit_id, function_code, exception_code, subfunction_code;
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void *p_save_proto_data;
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/* Make entries in Protocol column on summary display */
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col_set_str(pinfo->cinfo, COL_PROTOCOL, "Modbus/TCP");
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col_clear(pinfo->cinfo, COL_INFO);
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transaction_id = tvb_get_ntohs(tvb, 0);
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protocol_id = tvb_get_ntohs(tvb, 2);
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len = tvb_get_ntohs(tvb, 4);
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unit_id = tvb_get_guint8(tvb, 6);
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function_code = tvb_get_guint8(tvb, 7) & 0x7F;
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/* Make entries in Info column on summary display */
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offset = 0;
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/* Find exception - last bit set in function code */
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if (tvb_get_guint8(tvb, 7) & 0x80) {
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exception_code = tvb_get_guint8(tvb, offset + 8);
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}
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else {
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exception_code = 0;
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}
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if ((function_code == ENCAP_INTERFACE_TRANSP) && (exception_code == 0)) {
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func_string = val_to_str_const(tvb_get_guint8(tvb, offset + 8), encap_interface_code_vals, "Encapsulated Interface Transport");
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subfunction_code = 1;
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}
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else if ((function_code == DIAGNOSTICS) && (exception_code == 0)) {
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func_string = val_to_str_const(tvb_get_ntohs(tvb, offset + 8), diagnostic_code_vals, "Diagnostics");
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subfunction_code = 1;
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}
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else {
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func_string = val_to_str(function_code, function_code_vals, "Unknown function (%d)");
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subfunction_code = 0;
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}
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/* "Request" or "Response" */
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packet_type = classify_packet(pinfo);
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if (check_col(pinfo->cinfo, COL_INFO))
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{
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switch ( packet_type ) {
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case QUERY_PACKET :
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pkt_type_str="query";
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break;
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case RESPONSE_PACKET :
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pkt_type_str="response";
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break;
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case CANNOT_CLASSIFY :
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err_str="Unable to classify as query or response.";
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pkt_type_str="unknown";
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break;
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default :
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break;
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}
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if ( exception_code != 0 )
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err_str="Exception returned ";
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if (subfunction_code == 0) {
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if (strlen(err_str) > 0) {
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col_add_fstr(pinfo->cinfo, COL_INFO,
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"%8s: trans: %5u; unit: %3u, func: %3u: %s. %s",
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pkt_type_str, transaction_id, unit_id,
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function_code, func_string, err_str);
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}
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else {
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col_add_fstr(pinfo->cinfo, COL_INFO,
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"%8s: trans: %5u; unit: %3u, func: %3u: %s",
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pkt_type_str, transaction_id, unit_id,
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function_code, func_string);
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}
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}
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else {
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if (strlen(err_str) > 0) {
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col_add_fstr(pinfo->cinfo, COL_INFO,
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"%8s: trans: %5u; unit: %3u, func: %3u/%3u: %s. %s",
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pkt_type_str, transaction_id, unit_id,
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function_code, subfunction_code, func_string, err_str);
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}
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else {
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col_add_fstr(pinfo->cinfo, COL_INFO,
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"%8s: trans: %5u; unit: %3u, func: %3u/%3u: %s",
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pkt_type_str, transaction_id, unit_id,
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function_code, subfunction_code, func_string);
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}
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}
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}
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/* if a tree exists, perform operations to add fields to it */
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if (tree)
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{
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mi = proto_tree_add_protocol_format(tree, proto_mbtcp, tvb, offset,
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len+6, "Modbus/TCP");
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mbtcp_tree = proto_item_add_subtree(mi, ett_mbtcp);
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/* Add items to protocol tree specific to Modbus/TCP */
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proto_tree_add_uint(mbtcp_tree, hf_mbtcp_transid, tvb, offset, 2, transaction_id);
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proto_tree_add_uint(mbtcp_tree, hf_mbtcp_protid, tvb, offset + 2, 2, protocol_id);
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proto_tree_add_uint(mbtcp_tree, hf_mbtcp_len, tvb, offset + 4, 2, len);
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proto_tree_add_uint(mbtcp_tree, hf_mbtcp_unitid, tvb, offset + 6, 1, unit_id);
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/* dissect the Modbus PDU */
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next_tvb = tvb_new_subset( tvb, offset+7, len-1, len-1);
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/* keep packet context */
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p_save_proto_data = p_get_proto_data( pinfo->fd, proto_mbtcp );
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p_remove_proto_data(pinfo->fd, proto_mbtcp);
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p_add_proto_data(pinfo->fd, proto_mbtcp, GINT_TO_POINTER(packet_type));
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/* Show the undissected payload */
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if( tvb_length_remaining(tvb, offset) > 0 )
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call_dissector(modbus_handle, next_tvb, pinfo, tree);
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p_remove_proto_data(pinfo->fd, proto_mbtcp);
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p_add_proto_data(pinfo->fd, proto_mbtcp, p_save_proto_data);
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}
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}
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static guint
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get_mbtcp_pdu_len(packet_info *pinfo _U_, tvbuff_t *tvb, int offset)
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{
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guint16 plen;
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/*
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* Get the length of the data from the encapsulation header.
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*/
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plen = tvb_get_ntohs(tvb, offset + 4);
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/*
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* That length doesn't include the encapsulation header itself;
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* add that in.
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*/
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return plen + 6;
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}
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static int
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dissect_mbtcp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
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{
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/* Make sure there's at least enough data to determine its a Modbus packet */
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if (!tvb_bytes_exist(tvb, 0, 8))
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return 0;
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/* check that it actually looks like Modbus/TCP */
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/* protocol id == 0 */
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if(tvb_get_ntohs(tvb, 2) != 0 ){
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return 0;
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}
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/* length is at least 2 (unit_id + function_code) */
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if(tvb_get_ntohs(tvb, 4) < 2 ){
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return 0;
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}
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/* build up protocol tree and iterate over multiple packets */
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tcp_dissect_pdus(tvb, pinfo, tree, mbtcp_desegment, 6,
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get_mbtcp_pdu_len, dissect_mbtcp_pdu);
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return tvb_length(tvb);
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}
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static int
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dissect_mbudp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
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{
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/* Make sure there's at least enough data to determine its a Modbus packet */
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if (!tvb_bytes_exist(tvb, 0, 8))
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return 0;
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/* check that it actually looks like Modbus/UDP */
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/* protocol id == 0 */
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if(tvb_get_ntohs(tvb, 2) != 0 ){
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return 0;
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}
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/* length is at least 2 (unit_id + function_code) */
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if(tvb_get_ntohs(tvb, 4) < 2 ){
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return 0;
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}
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/* dissect the PDU */
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dissect_mbtcp_pdu(tvb, pinfo, tree);
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return tvb_length(tvb);
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}
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/* Code to allow special handling of mbtcp data */
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static void
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dissect_mbtcp_data(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, guint8 function_code, gint payload_start, gint payload_len)
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{
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gint reported_len;
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tvbuff_t *next_tvb;
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reported_len = tvb_reported_length_remaining(tvb, payload_start);
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if ( payload_start < 0 || ( payload_len + payload_start ) == 0 )
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return;
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if ( payload_len != reported_len ) {
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proto_tree_add_bytes_format(tree, hf_modbus_data, tvb, payload_start, payload_len, NULL, "Data");
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return;
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}
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next_tvb = tvb_new_subset(tvb, payload_start, payload_len, reported_len);
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|
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switch ( function_code ) {
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default:
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if ( ! dissector_try_string(mbtcp_dissector_table, "data", next_tvb, pinfo, tree) )
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proto_tree_add_bytes_format(tree, hf_modbus_data, tvb, payload_start, payload_len, NULL, "Data");
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break;
|
|
}
|
|
}
|
|
|
|
/* Code to actually dissect the packets */
|
|
static int
|
|
dissect_modbus(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
|
|
{
|
|
proto_tree *modbus_tree, *group_tree, *event_tree,
|
|
*event_item_tree, *device_objects_tree,
|
|
*device_objects_item_tree;
|
|
proto_item *mi, *mf, *me, *mei, *doe, *doie;
|
|
int offset, group_offset, packet_type, temp_data;
|
|
const char *func_string = "";
|
|
gint payload_start, payload_len, event_index,
|
|
i, byte_cnt, len, num_objects, object_index,
|
|
object_len;
|
|
guint32 group_byte_cnt, group_word_cnt;
|
|
guint8 function_code, exception_code, mei_code, event_code, object_type;
|
|
guint16 diagnostic_code;
|
|
|
|
/* Don't need to do anything if there's no tree */
|
|
if (tree == NULL)
|
|
return tvb_length(tvb);
|
|
|
|
len = tvb_length_remaining(tvb, 0);
|
|
function_code = tvb_get_guint8(tvb, 0) & 0x7F;
|
|
|
|
/* Find exception - last bit set in function code */
|
|
if (tvb_get_guint8(tvb, 0) & 0x80 ) {
|
|
exception_code = tvb_get_guint8(tvb, 1);
|
|
}
|
|
else {
|
|
exception_code = 0;
|
|
}
|
|
|
|
/* "Request" or "Response" */
|
|
packet_type = GPOINTER_TO_INT(p_get_proto_data( pinfo->fd, proto_mbtcp ));
|
|
|
|
/* Make entries in Info column on summary display */
|
|
offset = 0;
|
|
|
|
/* Add items to protocol tree specific to Modbus generic */
|
|
mf = proto_tree_add_text(tree, tvb, offset, len, "Modbus");
|
|
modbus_tree = proto_item_add_subtree(mf, ett_modbus_hdr);
|
|
mi = proto_tree_add_uint(modbus_tree, hf_mbtcp_functioncode, tvb, offset, 1,
|
|
function_code);
|
|
|
|
/** detail payload as a function of exception/function code */
|
|
func_string = val_to_str_const(function_code, function_code_vals, "Unknown function");
|
|
|
|
payload_start = offset + 1;
|
|
payload_len = len - 1;
|
|
if (exception_code != 0) {
|
|
proto_item_set_text(mi, "function %u: %s. Exception: %s",
|
|
function_code,
|
|
func_string,
|
|
val_to_str(exception_code,
|
|
exception_code_vals,
|
|
"Unknown exception code (%u)"));
|
|
proto_tree_add_uint(modbus_tree, hf_modbus_exceptioncode, tvb, payload_start, 1,
|
|
exception_code);
|
|
}
|
|
else {
|
|
proto_item_set_text(mi, "function %u: %s", function_code,
|
|
func_string);
|
|
switch (function_code) {
|
|
|
|
case READ_COILS:
|
|
case READ_INPUT_DISCRETES:
|
|
if (packet_type == QUERY_PACKET) {
|
|
proto_tree_add_item(modbus_tree, hf_modbus_reference, tvb, payload_start, 2, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(modbus_tree, hf_modbus_bitcnt, tvb, payload_start + 2, 2, ENC_BIG_ENDIAN);
|
|
}
|
|
else if (packet_type == RESPONSE_PACKET) {
|
|
byte_cnt = (guint32)tvb_get_guint8(tvb, payload_start);
|
|
proto_tree_add_uint(modbus_tree, hf_modbus_bytecnt, tvb, payload_start, 1, byte_cnt);
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start + 1, byte_cnt);
|
|
}
|
|
break;
|
|
|
|
case READ_MULT_REGS:
|
|
case READ_INPUT_REGS:
|
|
if (packet_type == QUERY_PACKET) {
|
|
proto_tree_add_item(modbus_tree, hf_modbus_reference, tvb, payload_start, 2, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(modbus_tree, hf_modbus_wordcnt, tvb, payload_start + 2, 2, ENC_BIG_ENDIAN);
|
|
}
|
|
else if (packet_type == RESPONSE_PACKET) {
|
|
byte_cnt = (guint32)tvb_get_guint8(tvb, payload_start);
|
|
proto_tree_add_uint(modbus_tree, hf_modbus_bytecnt, tvb, payload_start, 1, byte_cnt);
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start + 1, byte_cnt);
|
|
}
|
|
break;
|
|
|
|
case WRITE_COIL:
|
|
if (packet_type == QUERY_PACKET) {
|
|
proto_tree_add_item(modbus_tree, hf_modbus_reference, tvb, payload_start, 2, ENC_BIG_ENDIAN);
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start + 2, 1);
|
|
proto_tree_add_text(modbus_tree, tvb, payload_start + 3, 1, "Padding");
|
|
}
|
|
else if (packet_type == RESPONSE_PACKET) {
|
|
proto_tree_add_item(modbus_tree, hf_modbus_reference, tvb, payload_start, 2, ENC_BIG_ENDIAN);
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start + 2, 1);
|
|
proto_tree_add_text(modbus_tree, tvb, payload_start + 3, 1, "Padding");
|
|
}
|
|
break;
|
|
|
|
case WRITE_SINGLE_REG:
|
|
if (packet_type == QUERY_PACKET) {
|
|
proto_tree_add_item(modbus_tree, hf_modbus_reference, tvb, payload_start, 2, ENC_BIG_ENDIAN);
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start + 2, 2);
|
|
}
|
|
else if (packet_type == RESPONSE_PACKET) {
|
|
proto_tree_add_item(modbus_tree, hf_modbus_reference, tvb, payload_start, 2, ENC_BIG_ENDIAN);
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start + 2, 2);
|
|
}
|
|
break;
|
|
|
|
case READ_EXCEPT_STAT:
|
|
if (packet_type == RESPONSE_PACKET)
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start, 1);
|
|
break;
|
|
|
|
case DIAGNOSTICS:
|
|
if ((packet_type == QUERY_PACKET) || (packet_type == RESPONSE_PACKET)) {
|
|
diagnostic_code = tvb_get_ntohs(tvb, payload_start);
|
|
proto_tree_add_uint(modbus_tree, hf_modbus_diag_sf, tvb, payload_start, 2, diagnostic_code);
|
|
switch(diagnostic_code)
|
|
{
|
|
case RETURN_QUERY_DATA:
|
|
if (packet_type == QUERY_PACKET) {
|
|
if (payload_len > 2)
|
|
proto_tree_add_text(modbus_tree, tvb, payload_start+2, payload_len-2, "Request Data");
|
|
}
|
|
else if (packet_type == RESPONSE_PACKET) {
|
|
if (payload_len > 2)
|
|
proto_tree_add_text(modbus_tree, tvb, payload_start+2, payload_len-2, "Echo Data");
|
|
}
|
|
break;
|
|
case RESTART_COMMUNICATION_OPTION:
|
|
temp_data = tvb_get_ntohs(tvb, payload_start+2);
|
|
if (temp_data == 0) {
|
|
proto_tree_add_text(modbus_tree, tvb, payload_start+2, 2, "Leave Log");
|
|
}
|
|
else if (temp_data == 0xFF) {
|
|
proto_tree_add_text(modbus_tree, tvb, payload_start+2, 2, "Clear Log");
|
|
}
|
|
else {
|
|
proto_tree_add_text(modbus_tree, tvb, payload_start+2, 2, "Unknown");
|
|
}
|
|
break;
|
|
case RETURN_DIAGNOSTIC_REGISTER:
|
|
if (packet_type == QUERY_PACKET) {
|
|
if (payload_len > 2)
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start+2, payload_len-2);
|
|
}
|
|
else if (packet_type == RESPONSE_PACKET) {
|
|
temp_data = tvb_get_ntohs(tvb, payload_start+2);
|
|
proto_tree_add_text( modbus_tree, tvb, payload_start+2, 2, "Diagnostic Register Contents 0x%04x", temp_data );
|
|
}
|
|
break;
|
|
case CHANGE_ASCII_INPUT_DELIMITER:
|
|
temp_data = tvb_get_guint8(tvb, payload_start+2);
|
|
proto_tree_add_text( modbus_tree, tvb, payload_start+2, 1, "CHAR 0x%02x", temp_data );
|
|
break;
|
|
case RETURN_BUS_MESSAGE_COUNT:
|
|
if (packet_type == QUERY_PACKET) {
|
|
if (payload_len > 2)
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start+2, payload_len-2);
|
|
}
|
|
else if (packet_type == RESPONSE_PACKET) {
|
|
temp_data = tvb_get_ntohs(tvb, payload_start+2);
|
|
proto_tree_add_text( modbus_tree, tvb, payload_start+2, 2, "Total Message Count %d", temp_data );
|
|
}
|
|
break;
|
|
case RETURN_BUS_COMM_ERROR_COUNT:
|
|
if (packet_type == QUERY_PACKET) {
|
|
if (payload_len > 2)
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start+2, payload_len-2);
|
|
}
|
|
else if (packet_type == RESPONSE_PACKET) {
|
|
temp_data = tvb_get_ntohs(tvb, payload_start+2);
|
|
proto_tree_add_text( modbus_tree, tvb, payload_start+2, 2, "CRC Error Count %d", temp_data );
|
|
}
|
|
break;
|
|
case RETURN_BUS_EXCEPTION_ERROR_COUNT:
|
|
if (packet_type == QUERY_PACKET) {
|
|
if (payload_len > 2)
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start+2, payload_len-2);
|
|
}
|
|
else if (packet_type == RESPONSE_PACKET) {
|
|
temp_data = tvb_get_ntohs(tvb, payload_start+2);
|
|
proto_tree_add_text( modbus_tree, tvb, payload_start+2, 2, "Exception Error Count %d", temp_data );
|
|
}
|
|
break;
|
|
case RETURN_SLAVE_MESSAGE_COUNT:
|
|
if (packet_type == QUERY_PACKET) {
|
|
if (payload_len > 2)
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start+2, payload_len-2);
|
|
}
|
|
else if (packet_type == RESPONSE_PACKET) {
|
|
temp_data = tvb_get_ntohs(tvb, payload_start+2);
|
|
proto_tree_add_text( modbus_tree, tvb, payload_start+2, 2, "Slave Message Count %d", temp_data );
|
|
}
|
|
break;
|
|
case RETURN_SLAVE_NO_RESPONSE_COUNT:
|
|
if (packet_type == QUERY_PACKET) {
|
|
if (payload_len > 2)
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start+2, payload_len-2);
|
|
}
|
|
else if (packet_type == RESPONSE_PACKET) {
|
|
temp_data = tvb_get_ntohs(tvb, payload_start+2);
|
|
proto_tree_add_text( modbus_tree, tvb, payload_start+2, 2, "Slave No Response Count %d", temp_data );
|
|
}
|
|
break;
|
|
case RETURN_SLAVE_NAK_COUNT:
|
|
if (packet_type == QUERY_PACKET) {
|
|
if (payload_len > 2)
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start+2, payload_len-2);
|
|
}
|
|
else if (packet_type == RESPONSE_PACKET) {
|
|
temp_data = tvb_get_ntohs(tvb, payload_start+2);
|
|
proto_tree_add_text( modbus_tree, tvb, payload_start+2, 2, "Slave NAK Count %d", temp_data );
|
|
}
|
|
break;
|
|
case RETURN_SLAVE_BUSY_COUNT:
|
|
if (packet_type == QUERY_PACKET) {
|
|
if (payload_len > 2)
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start+2, payload_len-2);
|
|
}
|
|
else if (packet_type == RESPONSE_PACKET) {
|
|
temp_data = tvb_get_ntohs(tvb, payload_start+2);
|
|
proto_tree_add_text( modbus_tree, tvb, payload_start+2, 2, "Slave Device Busy Count %d", temp_data );
|
|
}
|
|
break;
|
|
case RETURN_BUS_CHAR_OVERRUN_COUNT:
|
|
if (packet_type == QUERY_PACKET) {
|
|
if (payload_len > 2)
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start+2, payload_len-2);
|
|
}
|
|
else if (packet_type == RESPONSE_PACKET) {
|
|
temp_data = tvb_get_ntohs(tvb, payload_start+2);
|
|
proto_tree_add_text( modbus_tree, tvb, payload_start+2, 2, "Slave Character Overrun Count %d", temp_data );
|
|
}
|
|
break;
|
|
case CLEAR_OVERRUN_COUNTER_AND_FLAG:
|
|
case FORCE_LISTEN_ONLY_MODE:
|
|
case CLEAR_COUNTERS_AND_DIAG_REG:
|
|
default:
|
|
if (payload_len > 2)
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start+2, payload_len-2);
|
|
break;
|
|
}
|
|
}
|
|
break;
|
|
|
|
case GET_COMM_EVENT_CTRS:
|
|
if (packet_type == RESPONSE_PACKET) {
|
|
proto_tree_add_item(modbus_tree, hf_modbus_status, tvb, payload_start, 2, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(modbus_tree, hf_modbus_event_count, tvb, payload_start+2, 2, ENC_BIG_ENDIAN);
|
|
}
|
|
break;
|
|
|
|
case GET_COMM_EVENT_LOG:
|
|
if (packet_type == RESPONSE_PACKET) {
|
|
byte_cnt = (guint32)tvb_get_guint8(tvb, payload_start);
|
|
proto_tree_add_uint(modbus_tree, hf_modbus_bytecnt, tvb, payload_start, 1, byte_cnt);
|
|
proto_tree_add_item(modbus_tree, hf_modbus_status, tvb, payload_start+1, 2, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(modbus_tree, hf_modbus_event_count, tvb, payload_start+3, 2, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(modbus_tree, hf_modbus_message_count, tvb, payload_start+5, 2, ENC_BIG_ENDIAN);
|
|
if (byte_cnt-6 > 0) {
|
|
byte_cnt -= 6;
|
|
event_index = 0;
|
|
me = proto_tree_add_text(modbus_tree, tvb, payload_start+7, byte_cnt, "Events");
|
|
event_tree = proto_item_add_subtree(me, ett_events);
|
|
while (byte_cnt > 0) {
|
|
event_code = tvb_get_guint8(tvb, payload_start+7+event_index);
|
|
if (event_code == 0) {
|
|
proto_tree_add_text(event_tree, tvb, payload_start+7+event_index, 1, "Initiated Communication Restart");
|
|
}
|
|
else if (event_code == 4) {
|
|
proto_tree_add_text(event_tree, tvb, payload_start+7+event_index, 1, "Entered Listen Only Mode");
|
|
}
|
|
else if (event_code & REMOTE_DEVICE_RECV_EVENT_MASK) {
|
|
mei = proto_tree_add_text(event_tree, tvb, payload_start+7+event_index, 1, "Receive Event: 0x%02X", event_code);
|
|
event_item_tree = proto_item_add_subtree(mei, ett_events_recv);
|
|
|
|
/* add subtrees to describe each event bit */
|
|
proto_tree_add_item(event_item_tree, hf_modbus_event_recv_comm_err,
|
|
tvb, payload_start+7+event_index, 1, ENC_LITTLE_ENDIAN );
|
|
proto_tree_add_item(event_item_tree, hf_modbus_event_recv_char_over,
|
|
tvb, payload_start+7+event_index, 1, ENC_LITTLE_ENDIAN );
|
|
proto_tree_add_item(event_item_tree, hf_modbus_event_recv_lo_mode,
|
|
tvb, payload_start+7+event_index, 1, ENC_LITTLE_ENDIAN );
|
|
proto_tree_add_item(event_item_tree, hf_modbus_event_recv_broadcast,
|
|
tvb, payload_start+7+event_index, 1, ENC_LITTLE_ENDIAN );
|
|
}
|
|
else if ((event_code & REMOTE_DEVICE_SEND_EVENT_MASK) == REMOTE_DEVICE_SEND_EVENT_VALUE) {
|
|
mei = proto_tree_add_text(event_tree, tvb, payload_start+7+event_index, 1, "Send Event: 0x%02X", event_code);
|
|
event_item_tree = proto_item_add_subtree(mei, ett_events_send);
|
|
|
|
/* add subtrees to describe each event bit */
|
|
proto_tree_add_item(event_item_tree, hf_modbus_event_send_read_ex,
|
|
tvb, payload_start+7+event_index, 1, ENC_LITTLE_ENDIAN );
|
|
proto_tree_add_item(event_item_tree, hf_modbus_event_send_slave_abort_ex,
|
|
tvb, payload_start+7+event_index, 1, ENC_LITTLE_ENDIAN );
|
|
proto_tree_add_item(event_item_tree, hf_modbus_event_send_slave_busy_ex,
|
|
tvb, payload_start+7+event_index, 1, ENC_LITTLE_ENDIAN );
|
|
proto_tree_add_item(event_item_tree, hf_modbus_event_send_slave_nak_ex,
|
|
tvb, payload_start+7+event_index, 1, ENC_LITTLE_ENDIAN );
|
|
proto_tree_add_item(event_item_tree, hf_modbus_event_send_write_timeout,
|
|
tvb, payload_start+7+event_index, 1, ENC_LITTLE_ENDIAN );
|
|
proto_tree_add_item(event_item_tree, hf_modbus_event_send_lo_mode,
|
|
tvb, payload_start+7+event_index, 1, ENC_LITTLE_ENDIAN );
|
|
}
|
|
else {
|
|
proto_tree_add_text(event_tree, tvb, payload_start+7+event_index, 1, "Unknown Event");
|
|
}
|
|
|
|
byte_cnt--;
|
|
event_index++;
|
|
}
|
|
}
|
|
}
|
|
break;
|
|
|
|
case WRITE_MULT_COILS:
|
|
if (packet_type == QUERY_PACKET) {
|
|
proto_tree_add_item(modbus_tree, hf_modbus_reference, tvb, payload_start, 2, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(modbus_tree, hf_modbus_bitcnt, tvb, payload_start + 2, 2, ENC_BIG_ENDIAN);
|
|
byte_cnt = (guint32)tvb_get_guint8(tvb, payload_start + 4);
|
|
proto_tree_add_uint(modbus_tree, hf_modbus_bytecnt, tvb, payload_start + 4, 1,
|
|
byte_cnt);
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start + 5, byte_cnt);
|
|
}
|
|
else if (packet_type == RESPONSE_PACKET) {
|
|
proto_tree_add_item(modbus_tree, hf_modbus_reference, tvb, payload_start, 2, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(modbus_tree, hf_modbus_bitcnt, tvb, payload_start + 2, 2, ENC_BIG_ENDIAN);
|
|
}
|
|
break;
|
|
|
|
case WRITE_MULT_REGS:
|
|
if (packet_type == QUERY_PACKET) {
|
|
proto_tree_add_item(modbus_tree, hf_modbus_reference, tvb, payload_start, 2, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(modbus_tree, hf_modbus_wordcnt, tvb, payload_start + 2, 2, ENC_BIG_ENDIAN);
|
|
byte_cnt = (guint32)tvb_get_guint8(tvb, payload_start + 4);
|
|
proto_tree_add_uint(modbus_tree, hf_modbus_bytecnt, tvb, payload_start + 4, 1,
|
|
byte_cnt);
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start + 5, byte_cnt);
|
|
}
|
|
else if (packet_type == RESPONSE_PACKET) {
|
|
proto_tree_add_item(modbus_tree, hf_modbus_reference, tvb, payload_start, 2, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(modbus_tree, hf_modbus_wordcnt, tvb, payload_start + 2, 2, ENC_BIG_ENDIAN);
|
|
}
|
|
break;
|
|
|
|
case READ_FILE_RECORD:
|
|
if (packet_type == QUERY_PACKET) {
|
|
byte_cnt = (guint32)tvb_get_guint8(tvb, payload_start);
|
|
proto_tree_add_uint(modbus_tree, hf_modbus_bytecnt, tvb, payload_start, 1,
|
|
byte_cnt);
|
|
|
|
/* add subtrees to describe each group of packet */
|
|
group_offset = payload_start + 1;
|
|
for (i = 0; i < byte_cnt / 7; i++) {
|
|
mi = proto_tree_add_text( modbus_tree, tvb, group_offset, 7,
|
|
"Group %u", i);
|
|
group_tree = proto_item_add_subtree(mi, ett_group_hdr);
|
|
proto_tree_add_item(group_tree, hf_modbus_reftype, tvb, group_offset, 1, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(group_tree, hf_modbus_lreference, tvb, group_offset + 1, 4, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(group_tree, hf_modbus_wordcnt, tvb, group_offset + 5, 2, ENC_BIG_ENDIAN);
|
|
group_offset += 7;
|
|
}
|
|
}
|
|
else if (packet_type == RESPONSE_PACKET) {
|
|
byte_cnt = (guint32)tvb_get_guint8(tvb, payload_start);
|
|
proto_tree_add_uint(modbus_tree, hf_modbus_bytecnt, tvb, payload_start, 1,
|
|
byte_cnt);
|
|
|
|
/* add subtrees to describe each group of packet */
|
|
group_offset = payload_start + 1;
|
|
i = 0;
|
|
while (byte_cnt > 0) {
|
|
group_byte_cnt = (guint32)tvb_get_guint8(tvb, group_offset);
|
|
mi = proto_tree_add_text( modbus_tree, tvb, group_offset, group_byte_cnt + 1,
|
|
"Group %u", i);
|
|
group_tree = proto_item_add_subtree(mi, ett_group_hdr);
|
|
proto_tree_add_uint(group_tree, hf_modbus_bytecnt, tvb, group_offset, 1,
|
|
group_byte_cnt);
|
|
proto_tree_add_item(group_tree, hf_modbus_reftype, tvb, group_offset + 1, 1, ENC_BIG_ENDIAN);
|
|
dissect_mbtcp_data(tvb, pinfo, group_tree, function_code, group_offset + 2, group_byte_cnt - 1);
|
|
group_offset += (group_byte_cnt + 1);
|
|
byte_cnt -= (group_byte_cnt + 1);
|
|
i++;
|
|
}
|
|
}
|
|
break;
|
|
|
|
case WRITE_FILE_RECORD:
|
|
if ((packet_type == QUERY_PACKET) || (packet_type == RESPONSE_PACKET)) {
|
|
byte_cnt = (guint32)tvb_get_guint8(tvb, payload_start);
|
|
proto_tree_add_uint(modbus_tree, hf_modbus_bytecnt, tvb, payload_start, 1,
|
|
byte_cnt);
|
|
|
|
/* add subtrees to describe each group of packet */
|
|
group_offset = payload_start + 1;
|
|
i = 0;
|
|
while (byte_cnt > 0) {
|
|
group_word_cnt = tvb_get_ntohs(tvb, group_offset + 5);
|
|
group_byte_cnt = (2 * group_word_cnt) + 7;
|
|
mi = proto_tree_add_text( modbus_tree, tvb, group_offset,
|
|
group_byte_cnt, "Group %u", i);
|
|
group_tree = proto_item_add_subtree(mi, ett_group_hdr);
|
|
proto_tree_add_item(group_tree, hf_modbus_reftype, tvb, group_offset, 1, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(group_tree, hf_modbus_lreference, tvb, group_offset + 1, 4, ENC_BIG_ENDIAN);
|
|
proto_tree_add_uint(group_tree, hf_modbus_wordcnt, tvb, group_offset + 5, 2,
|
|
group_word_cnt);
|
|
dissect_mbtcp_data(tvb, pinfo, group_tree, function_code, group_offset + 7, group_byte_cnt - 7);
|
|
group_offset += group_byte_cnt;
|
|
byte_cnt -= group_byte_cnt;
|
|
i++;
|
|
}
|
|
}
|
|
break;
|
|
|
|
case MASK_WRITE_REG:
|
|
if ((packet_type == QUERY_PACKET) || (packet_type == RESPONSE_PACKET)) {
|
|
proto_tree_add_item(modbus_tree, hf_modbus_reference, tvb, payload_start, 2, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(modbus_tree, hf_modbus_andmask, tvb, payload_start + 2, 2, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(modbus_tree, hf_modbus_ormask, tvb, payload_start + 4, 2, ENC_BIG_ENDIAN);
|
|
}
|
|
break;
|
|
|
|
case READ_WRITE_REG:
|
|
if (packet_type == QUERY_PACKET) {
|
|
proto_tree_add_item(modbus_tree, hf_modbus_readref, tvb, payload_start, 2, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(modbus_tree, hf_modbus_readwordcnt, tvb, payload_start + 2, 2, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(modbus_tree, hf_modbus_writeref, tvb, payload_start + 4, 2, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(modbus_tree, hf_modbus_writewordcnt, tvb, payload_start + 6, 2, ENC_BIG_ENDIAN);
|
|
byte_cnt = (guint32)tvb_get_guint8(tvb, payload_start + 8);
|
|
proto_tree_add_uint(modbus_tree, hf_modbus_bytecnt, tvb, payload_start + 8, 1,
|
|
byte_cnt);
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start + 9, byte_cnt);
|
|
}
|
|
else if (packet_type == RESPONSE_PACKET) {
|
|
byte_cnt = (guint32)tvb_get_guint8(tvb, payload_start);
|
|
proto_tree_add_uint(modbus_tree, hf_modbus_bytecnt, tvb, payload_start, 1,
|
|
byte_cnt);
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start + 1, byte_cnt);
|
|
}
|
|
break;
|
|
|
|
case READ_FIFO_QUEUE:
|
|
if (packet_type == QUERY_PACKET)
|
|
proto_tree_add_item(modbus_tree, hf_modbus_reference, tvb, payload_start, 2, ENC_BIG_ENDIAN);
|
|
else if (packet_type == RESPONSE_PACKET) {
|
|
byte_cnt = (guint32)tvb_get_ntohs(tvb, payload_start);
|
|
proto_tree_add_uint(modbus_tree, hf_modbus_lbytecnt, tvb, payload_start, 2,
|
|
byte_cnt);
|
|
proto_tree_add_item(modbus_tree, hf_modbus_wordcnt, tvb, payload_start + 2, 2, ENC_BIG_ENDIAN);
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start + 4, byte_cnt - 2);
|
|
}
|
|
break;
|
|
|
|
case ENCAP_INTERFACE_TRANSP:
|
|
if (packet_type == QUERY_PACKET) {
|
|
proto_tree_add_item(modbus_tree, hf_modbus_mei, tvb, payload_start, 1, ENC_BIG_ENDIAN);
|
|
mei_code = tvb_get_guint8(tvb, payload_start);
|
|
switch (mei_code)
|
|
{
|
|
case READ_DEVICE_ID:
|
|
proto_tree_add_item(modbus_tree, hf_modbus_read_device_id, tvb, payload_start+1, 1, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(modbus_tree, hf_modbus_object_id, tvb, payload_start+2, 1, ENC_BIG_ENDIAN);
|
|
break;
|
|
|
|
case CANOPEN_REQ_RESP:
|
|
/* CANopen protocol not part of the Modbus/TCP specification */
|
|
default:
|
|
if (payload_len > 1)
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start, payload_len-1);
|
|
break;
|
|
}
|
|
}
|
|
else if (packet_type == RESPONSE_PACKET) {
|
|
proto_tree_add_item(modbus_tree, hf_modbus_mei, tvb, payload_start, 1, ENC_BIG_ENDIAN);
|
|
mei_code = tvb_get_guint8(tvb, payload_start);
|
|
switch (mei_code)
|
|
{
|
|
case READ_DEVICE_ID:
|
|
proto_tree_add_item(modbus_tree, hf_modbus_read_device_id, tvb, payload_start+1, 1, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(modbus_tree, hf_modbus_conformity_level, tvb, payload_start+2, 1, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(modbus_tree, hf_modbus_more_follows, tvb, payload_start+3, 1, ENC_BIG_ENDIAN);
|
|
proto_tree_add_item(modbus_tree, hf_modbus_next_object_id, tvb, payload_start+4, 1, ENC_BIG_ENDIAN);
|
|
num_objects = tvb_get_guint8(tvb, payload_start+5);
|
|
proto_tree_add_uint(modbus_tree, hf_modbus_num_objects, tvb, payload_start+5, 1, num_objects);
|
|
doe = proto_tree_add_text(modbus_tree, tvb, payload_start+6, payload_len-6, "Objects");
|
|
|
|
object_index = 0;
|
|
for (i = 1; i <= num_objects; i++)
|
|
{
|
|
device_objects_tree = proto_item_add_subtree(doe, ett_device_id_objects);
|
|
|
|
/* add each "object item" as its own subtree */
|
|
|
|
/* compute length of object */
|
|
object_type = tvb_get_guint8(tvb, payload_start+6+object_index);
|
|
object_len = tvb_get_guint8(tvb, payload_start+6+object_index+1);
|
|
|
|
doie = proto_tree_add_text(device_objects_tree, tvb, payload_start+6+object_index, 2+object_len, "Object #%d", i);
|
|
device_objects_item_tree = proto_item_add_subtree(doie, ett_device_id_object_items);
|
|
|
|
proto_tree_add_item(device_objects_item_tree, hf_modbus_object_id, tvb, payload_start+6+object_index, 1, ENC_BIG_ENDIAN);
|
|
object_index++;
|
|
|
|
proto_tree_add_uint(device_objects_item_tree, hf_modbus_list_object_len, tvb, payload_start+6+object_index, 1, object_len);
|
|
object_index++;
|
|
|
|
if (object_type < 7)
|
|
{
|
|
proto_tree_add_item(device_objects_item_tree, hf_modbus_object_str_value, tvb, payload_start+6+object_index, object_len, ENC_ASCII|ENC_NA);
|
|
}
|
|
else
|
|
{
|
|
if (object_len > 0)
|
|
proto_tree_add_text(device_objects_item_tree, tvb, payload_start+6+object_index, object_len, "Object Value");
|
|
}
|
|
object_index += object_len;
|
|
}
|
|
break;
|
|
|
|
case CANOPEN_REQ_RESP:
|
|
/* CANopen protocol not part of the Modbus/TCP specification */
|
|
default:
|
|
if (payload_len > 1)
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start, payload_len-1);
|
|
break;
|
|
}
|
|
}
|
|
break;
|
|
|
|
case REPORT_SLAVE_ID:
|
|
default:
|
|
if (payload_len > 0)
|
|
dissect_mbtcp_data(tvb, pinfo, modbus_tree, function_code, payload_start, payload_len);
|
|
break;
|
|
}
|
|
}
|
|
|
|
return tvb_length(tvb);
|
|
}
|
|
|
|
|
|
/* Register the protocol with Wireshark */
|
|
|
|
void
|
|
proto_register_modbus(void)
|
|
{
|
|
|
|
/* Setup list of header fields See Section 1.6.1 for details*/
|
|
static hf_register_info hf[] = {
|
|
/* Modbus/TCP header fields */
|
|
{ &hf_mbtcp_transid,
|
|
{ "transaction identifier", "mbtcp.trans_id",
|
|
FT_UINT16, BASE_DEC, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_mbtcp_protid,
|
|
{ "protocol identifier", "mbtcp.prot_id",
|
|
FT_UINT16, BASE_DEC, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_mbtcp_len,
|
|
{ "length", "mbtcp.len",
|
|
FT_UINT16, BASE_DEC, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
/* Modbus header fields */
|
|
{ &hf_mbtcp_unitid,
|
|
{ "unit identifier", "mbtcp.modbus.unit_id",
|
|
FT_UINT8, BASE_DEC, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_mbtcp_functioncode,
|
|
{ "function code", "mbtcp.modbus.func_code",
|
|
FT_UINT8, BASE_DEC, VALS(function_code_vals), 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_reference,
|
|
{ "reference number", "mbtcp.modbus.reference_num",
|
|
FT_UINT16, BASE_DEC, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_lreference,
|
|
{ "reference number (32 bit)", "mbtcp.modbus.reference_num_32",
|
|
FT_UINT32, BASE_DEC, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_reftype,
|
|
{ "reference type", "mbtcp.modbus.reference_type",
|
|
FT_UINT8, BASE_DEC, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_readref,
|
|
{ "read reference number", "mbtcp.modbus.read_reference_num",
|
|
FT_UINT16, BASE_DEC, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_writeref,
|
|
{ "write reference number", "mbtcp.modbus.write_reference_num",
|
|
FT_UINT16, BASE_DEC, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_wordcnt,
|
|
{ "word count", "mbtcp.modbus.word_cnt",
|
|
FT_UINT16, BASE_DEC, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_readwordcnt,
|
|
{ "read word count", "mbtcp.modbus.read_word_cnt",
|
|
FT_UINT16, BASE_DEC, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_writewordcnt,
|
|
{ "write word count", "mbtcp.modbus.write_word_cnt",
|
|
FT_UINT16, BASE_DEC, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_bitcnt,
|
|
{ "bit count", "mbtcp.modbus.bit_cnt",
|
|
FT_UINT16, BASE_DEC, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_bytecnt,
|
|
{ "byte count", "mbtcp.modbus.byte_cnt",
|
|
FT_UINT8, BASE_DEC, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_lbytecnt,
|
|
{ "byte count (16-bit)", "mbtcp.modbus.byte_cnt_16",
|
|
FT_UINT8, BASE_DEC, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_exceptioncode,
|
|
{ "exception code", "mbtcp.modbus.exception_code",
|
|
FT_UINT8, BASE_DEC, VALS(exception_code_vals), 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_diag_sf,
|
|
{ "diagnostic code", "mbtcp.modbus.diagnostic_code",
|
|
FT_UINT16, BASE_DEC, VALS(diagnostic_code_vals), 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_status,
|
|
{ "status", "mbtcp.modbus.ev_status",
|
|
FT_UINT16, BASE_HEX, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_event_count,
|
|
{ "event count", "mbtcp.modbus.ev_count",
|
|
FT_UINT16, BASE_DEC, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_message_count,
|
|
{ "message count", "mbtcp.modbus.ev_msg_count",
|
|
FT_UINT16, BASE_DEC, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_event_recv_comm_err,
|
|
{ "Communication Error", "mbtcp.modbus.ev_recv_comm_err",
|
|
FT_UINT8, BASE_DEC, NULL, 0x02,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_event_recv_char_over,
|
|
{ "Character Overrun", "mbtcp.modbus.ev_recv_char_over",
|
|
FT_UINT8, BASE_DEC, NULL, 0x10,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_event_recv_lo_mode,
|
|
{ "Currently in Listen Only Mode", "mbtcp.modbus.ev_recv_lo_mode",
|
|
FT_UINT8, BASE_DEC, NULL, 0x20,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_event_recv_broadcast,
|
|
{ "Broadcast Received", "mbtcp.modbus.ev_recv_broadcast",
|
|
FT_UINT8, BASE_DEC, NULL, 0x40,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_event_send_read_ex,
|
|
{ "Read Exception Sent", "mbtcp.modbus.ev_send_read_ex",
|
|
FT_UINT8, BASE_DEC, NULL, 0x01,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_event_send_slave_abort_ex,
|
|
{ "Slave Abort Exception Sent", "mbtcp.modbus.ev_send_slave_abort_ex",
|
|
FT_UINT8, BASE_DEC, NULL, 0x02,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_event_send_slave_busy_ex,
|
|
{ "Slave Busy Exception Sent", "mbtcp.modbus.ev_send_slave_busy_ex",
|
|
FT_UINT8, BASE_DEC, NULL, 0x04,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_event_send_slave_nak_ex,
|
|
{ "Slave Program NAK Exception Sent", "mbtcp.modbus.ev_send_slave_nak_ex",
|
|
FT_UINT8, BASE_DEC, NULL, 0x08,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_event_send_write_timeout,
|
|
{ "Write Timeout Error Occurred", "mbtcp.modbus.ev_send_write_timeout",
|
|
FT_UINT8, BASE_DEC, NULL, 0x10,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_event_send_lo_mode,
|
|
{ "Currently in Listen Only Mode", "mbtcp.modbus.ev_send_lo_mode",
|
|
FT_UINT8, BASE_DEC, NULL, 0x20,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_andmask,
|
|
{ "AND mask", "mbtcp.modbus.and_mask",
|
|
FT_UINT16, BASE_HEX, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_ormask,
|
|
{ "OR mask", "mbtcp.modbus.or_mask",
|
|
FT_UINT16, BASE_HEX, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_data,
|
|
{ "Data", "mbtcp.modbus.data",
|
|
FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_mei,
|
|
{ "MEI type", "mbtcp.modbus.mei",
|
|
FT_UINT8, BASE_DEC, VALS(encap_interface_code_vals), 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_read_device_id,
|
|
{ "Read Device ID", "mbtcp.modbus.read_device_id",
|
|
FT_UINT8, BASE_DEC, VALS(read_device_id_vals), 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_object_id,
|
|
{ "Object ID", "mbtcp.modbus.object_id",
|
|
FT_UINT8, BASE_DEC, VALS(object_id_vals), 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_num_objects,
|
|
{ "Number of Objects", "mbtcp.modbus.num_objects",
|
|
FT_UINT8, BASE_DEC, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_list_object_len,
|
|
{ "Object length", "mbtcp.modbus.objects_len",
|
|
FT_UINT8, BASE_DEC, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_conformity_level,
|
|
{ "Conformity Level", "mbtcp.modbus.conformity_level",
|
|
FT_UINT8, BASE_HEX, VALS(conformity_level_vals), 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_more_follows,
|
|
{ "More Follows", "mbtcp.modbus.more_follows",
|
|
FT_UINT8, BASE_HEX, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_next_object_id,
|
|
{ "Next Object ID", "mbtcp.modbus.next_object_id",
|
|
FT_UINT8, BASE_DEC, NULL, 0x0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_modbus_object_str_value,
|
|
{ "Object String Value", "mbtcp.modbus.object_str_value",
|
|
FT_STRING, BASE_NONE, NULL, 0x0,
|
|
NULL, HFILL }
|
|
}
|
|
};
|
|
|
|
/* Setup protocol subtree array */
|
|
static gint *ett[] = {
|
|
&ett_mbtcp,
|
|
&ett_modbus_hdr,
|
|
&ett_group_hdr,
|
|
&ett_events,
|
|
&ett_events_recv,
|
|
&ett_events_send,
|
|
&ett_device_id_objects,
|
|
&ett_device_id_object_items
|
|
};
|
|
|
|
/* Register the protocol name and description */
|
|
proto_mbtcp = proto_register_protocol("Modbus/TCP", "Modbus/TCP", "mbtcp");
|
|
proto_modbus = proto_register_protocol("Modbus", "Modbus", "modbus");
|
|
|
|
/* Registering protocol to be called by another dissector */
|
|
new_register_dissector("mbtcp", dissect_mbtcp, proto_mbtcp);
|
|
new_register_dissector("modbus", dissect_modbus, proto_modbus);
|
|
|
|
/* Registering subdissectors table */
|
|
mbtcp_dissector_table = register_dissector_table("mbtcp.modbus.data", "Modbus/TCP Data", FT_STRING, BASE_NONE);
|
|
modbus_dissector_table = register_dissector_table("mbtcp.prot_id", "protocol identifier", FT_UINT16, BASE_DEC);
|
|
|
|
/* Required function calls to register the header fields and subtrees used */
|
|
proto_register_field_array(proto_mbtcp, hf, array_length(hf));
|
|
proto_register_subtree_array(ett, array_length(ett));
|
|
}
|
|
|
|
|
|
/* If this dissector uses sub-dissector registration add a registration routine.
|
|
This format is required because a script is used to find these routines and
|
|
create the code that calls these routines.
|
|
*/
|
|
void
|
|
proto_reg_handoff_mbtcp(void)
|
|
{
|
|
dissector_handle_t mbtcp_handle, mbudp_handle;
|
|
|
|
mbtcp_handle = new_create_dissector_handle(dissect_mbtcp, proto_mbtcp);
|
|
dissector_add_uint("tcp.port", PORT_MBTCP, mbtcp_handle);
|
|
|
|
mbudp_handle = new_create_dissector_handle(dissect_mbudp, proto_mbtcp);
|
|
dissector_add_uint("udp.port", PORT_MBTCP, mbudp_handle);
|
|
|
|
modbus_handle = new_create_dissector_handle(dissect_modbus, proto_modbus);
|
|
dissector_add_uint("mbtcp.prot_id", MODBUS_PROTOCOL_ID, modbus_handle);
|
|
}
|