* Updated to v1.1b of the Modbus Application Protocol specification
* Michael Mann * Copyright 2011
*
- * Updates Oct/Nov 2012 (Chris Bontje, cbontje[*at*]gmail.com)
- * - Some re-factoring to include support for serial Modbus RTU encapsulated in TCP messages
- * - Minor text/syntax clean-up
- * - Include decoding of holding/input response register data
- * - Optionally decode holding/input registers as UINT16, UINT32, 32-bit Float IEEE/Modicon
- * - Add various register address formatting options as "Raw", "Modicon 5-digit", "Modicon 6-digit"
- *
- * Updates Aug 2013 (Chris Bontje)
- * - Improved dissection support for serial Modbus RTU with detection of query or response messages
- *
*****************************************************************************************************
* A brief explanation of the distinction between Modbus/TCP and Modbus RTU over TCP:
*
* H = 16-bit CRC
*
*****************************************************************************************************
- * $Id$
- *
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
#include "config.h"
#include <epan/packet.h>
-#include <epan/wmem/wmem.h>
#include "packet-tcp.h"
#include "packet-mbtcp.h"
#include <epan/prefs.h>
#include <epan/expert.h>
-#include <epan/crc16-tvb.h> /* For CRC verification */\
+#include <epan/crc16-tvb.h> /* For CRC verification */
+#include <epan/proto_data.h>
+
+void proto_register_modbus(void);
+void proto_reg_handoff_mbtcp(void);
+void proto_reg_handoff_mbrtu(void);
/* Initialize the protocol and registered fields */
static int proto_mbtcp = -1;
+static int proto_mbudp = -1;
static int proto_mbrtu = -1;
static int proto_modbus = -1;
static int hf_mbtcp_transid = -1;
static int hf_mbtcp_protid = -1;
static int hf_mbtcp_len = -1;
static int hf_mbtcp_unitid = -1;
-static int hf_mbtcp_functioncode = -1;
+static int hf_modbus_request_frame = -1;
+static int hf_modbus_functioncode = -1;
static int hf_modbus_reference = -1;
+static int hf_modbus_padding = -1;
static int hf_modbus_lreference = -1;
static int hf_modbus_reftype = -1;
static int hf_modbus_readref = -1;
static int hf_modbus_diag_restart_communication_option = -1;
static int hf_modbus_diag_return_diag_register = -1;
static int hf_modbus_diag_ascii_input_delimiter = -1;
+static int hf_modbus_diag_clear_ctr_diag_reg = -1;
static int hf_modbus_diag_return_bus_message_count = -1;
static int hf_modbus_diag_return_bus_comm_error_count = -1;
static int hf_modbus_diag_return_bus_exception_error_count = -1;
static int hf_modbus_diag_return_slave_busy_count = -1;
static int hf_modbus_diag_return_bus_char_overrun_count = -1;
static int hf_modbus_status = -1;
+static int hf_modbus_event = -1;
static int hf_modbus_event_count = -1;
static int hf_modbus_message_count = -1;
static int hf_modbus_event_recv_comm_err = -1;
static int hf_modbus_more_follows = -1;
static int hf_modbus_next_object_id = -1;
static int hf_modbus_object_str_value = -1;
-static int hf_modbus_reg_uint16 = -1;
-static int hf_modbus_reg_uint32 = -1;
-static int hf_modbus_reg_ieee_float = -1;
-static int hf_modbus_reg_modicon_float = -1;
+static int hf_modbus_object_value = -1;
+static int hf_modbus_reg16 = -1;
+static int hf_modbus_reg32 = -1;
static int hf_mbrtu_unitid = -1;
static int hf_mbrtu_crc16 = -1;
+static int hf_mbrtu_crc16_status = -1;
/* Initialize the subtree pointers */
static gint ett_mbtcp = -1;
static expert_field ei_mbrtu_crc16_incorrect = EI_INIT;
static expert_field ei_modbus_data_decode = EI_INIT;
+static expert_field ei_mbtcp_cannot_classify = EI_INIT;
static dissector_handle_t modbus_handle;
static dissector_handle_t mbtcp_handle;
+static dissector_handle_t mbudp_handle;
static dissector_handle_t mbrtu_handle;
static dissector_table_t modbus_data_dissector_table;
/* Globals for Modbus/TCP Preferences */
static gboolean mbtcp_desegment = TRUE;
static guint global_mbus_tcp_port = PORT_MBTCP; /* Port 502, by default */
-static gint global_mbus_tcp_register_format = MBTCP_PREF_REGISTER_FORMAT_UINT16;
-static gint global_mbus_tcp_register_addr_type = MBTCP_PREF_REGISTER_ADDR_RAW;
+static guint global_mbus_udp_port = PORT_MBTCP; /* Port 502, by default */
/* Globals for Modbus RTU over TCP Preferences */
static gboolean mbrtu_desegment = TRUE;
-static guint global_mbus_rtu_port = PORT_MBRTU; /* 0, by default */
-static gint global_mbus_rtu_register_format = MBTCP_PREF_REGISTER_FORMAT_UINT16;
-static gint global_mbus_rtu_register_addr_type = MBTCP_PREF_REGISTER_ADDR_RAW;
+static guint global_mbus_tcp_rtu_port = PORT_MBRTU; /* 0, by default */
+static guint global_mbus_udp_rtu_port = PORT_MBRTU; /* 0, by default */
static gboolean mbrtu_crc = FALSE;
+/* Globals for Modbus Preferences */
+static gint global_mbus_register_format = MODBUS_PREF_REGISTER_FORMAT_UINT16;
+
static int
-classify_mbtcp_packet(packet_info *pinfo)
+classify_mbtcp_packet(packet_info *pinfo, guint port)
{
/* see if nature of packets can be derived from src/dst ports */
/* if so, return as found */
/* the Modbus/TCP transaction ID for each pair of messages would allow for detection based on a new seq. number. */
/* Otherwise, we can stick with this method; a configurable port option has been added to allow for usage of */
/* user ports either than the default of 502. */
- if (( pinfo->srcport == global_mbus_tcp_port ) && ( pinfo->destport != global_mbus_tcp_port ))
+ if (( pinfo->srcport == port ) && ( pinfo->destport != port ))
return RESPONSE_PACKET;
- if (( pinfo->srcport != global_mbus_tcp_port ) && ( pinfo->destport == global_mbus_tcp_port ))
+ if (( pinfo->srcport != port ) && ( pinfo->destport == port ))
return QUERY_PACKET;
/* else, cannot classify */
}
static int
-classify_mbrtu_packet(packet_info *pinfo, tvbuff_t *tvb)
+classify_mbrtu_packet(packet_info *pinfo, tvbuff_t *tvb, guint port)
{
+ guint8 func, len;
+
+ func = tvb_get_guint8(tvb, 1);
+ len = tvb_reported_length(tvb);
+
/* see if nature of packets can be derived from src/dst ports */
/* if so, return as found */
- if (( pinfo->srcport == global_mbus_rtu_port ) && ( pinfo->destport != global_mbus_rtu_port ))
+ if (( pinfo->srcport == port ) && ( pinfo->destport != port ))
return RESPONSE_PACKET;
- if (( pinfo->srcport != global_mbus_rtu_port ) && ( pinfo->destport == global_mbus_rtu_port ))
+ if (( pinfo->srcport != port ) && ( pinfo->destport == port ))
return QUERY_PACKET;
- /* Special case for serial-captured packets that don't have an Ethernet header */
+
+ /* We may not have an Ethernet header or unique ports. */
/* Dig into these a little deeper to try to guess the message type */
- if (!pinfo->srcport) {
- /* If length is 8, this is either a query or very short response */
- if (tvb_length(tvb) == 8) {
+
+ /* The 'exception' bit is set, so this is a response */
+ if (func & 0x80) {
+ return RESPONSE_PACKET;
+ }
+ switch (func) {
+ case READ_COILS:
+ case READ_DISCRETE_INPUTS:
/* Only possible to get a response message of 8 bytes with Discrete or Coils */
- if ((tvb_get_guint8(tvb, 1) == READ_COILS) || (tvb_get_guint8(tvb, 1) == READ_DISCRETE_INPUTS)) {
+ if (len == 8) {
/* If this is, in fact, a response then the data byte count will be 3 */
/* This will correctly identify all messages except for those that are discrete or coil polls */
/* where the base address range happens to have 0x03 in the upper 16-bit address register */
}
}
else {
+ return RESPONSE_PACKET;
+ }
+ break;
+
+ case READ_HOLDING_REGS:
+ case READ_INPUT_REGS:
+ case WRITE_SINGLE_COIL:
+ case WRITE_SINGLE_REG:
+ if (len == 8) {
return QUERY_PACKET;
}
- }
- else {
- return RESPONSE_PACKET;
- }
+ else {
+ return RESPONSE_PACKET;
+ }
+ break;
+
+ case WRITE_MULT_REGS:
+ case WRITE_MULT_COILS:
+ if (len == 8) {
+ return RESPONSE_PACKET;
+ }
+ else {
+ return QUERY_PACKET;
+ }
+ break;
}
+
/* else, cannot classify */
return CANNOT_CLASSIFY;
}
{ READ_WRITE_REG, "Read Write Register" },
{ READ_FIFO_QUEUE, "Read FIFO Queue" },
{ ENCAP_INTERFACE_TRANSP, "Encapsulated Interface Transport" },
+ { UNITY_SCHNEIDER, "Unity (Schneider)" },
{ 0, NULL }
};
};
static const enum_val_t mbus_register_format[] = {
- { "UINT16 ", "UINT16 ", MBTCP_PREF_REGISTER_FORMAT_UINT16 },
- { "UINT32 ", "UINT32 ", MBTCP_PREF_REGISTER_FORMAT_UINT32 },
- { "IEEE FLT ", "IEEE FLT ", MBTCP_PREF_REGISTER_FORMAT_IEEE_FLOAT },
- { "MODICON FLT", "MODICON FLT", MBTCP_PREF_REGISTER_FORMAT_MODICON_FLOAT },
- { NULL, NULL, 0 }
-};
-
-static const enum_val_t mbus_register_addr_type[] = {
- { "RAW ", "RAW ", MBTCP_PREF_REGISTER_ADDR_RAW },
- { "MODICON 5-DIGIT", "MODICON 5-DIGIT", MBTCP_PREF_REGISTER_ADDR_MOD5 },
- { "MODICON 6-DIGIT", "MODICON 6-DIGIT", MBTCP_PREF_REGISTER_ADDR_MOD6 },
+ { "UINT16 ", "UINT16 ", MODBUS_PREF_REGISTER_FORMAT_UINT16 },
+ { "INT16 ", "INT16 ", MODBUS_PREF_REGISTER_FORMAT_INT16 },
+ { "UINT32 ", "UINT32 ", MODBUS_PREF_REGISTER_FORMAT_UINT32 },
+ { "INT32 ", "INT32 ", MODBUS_PREF_REGISTER_FORMAT_INT32 },
+ { "IEEE FLT ", "IEEE FLT ", MODBUS_PREF_REGISTER_FORMAT_IEEE_FLOAT },
+ { "MODICON FLT", "MODICON FLT", MODBUS_PREF_REGISTER_FORMAT_MODICON_FLOAT },
{ NULL, NULL, 0 }
};
/* Code to dissect Modbus/TCP packets */
static int
-dissect_mbtcp_pdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
+dissect_mbtcp_pdu_common(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int proto, guint port)
{
/* Set up structures needed to add the protocol subtree and manage it */
proto_item *mi;
const char *err_str = "";
guint16 transaction_id, protocol_id, len;
guint8 unit_id, function_code, exception_code, subfunction_code;
- void *p_save_proto_data;
- modbus_request_info_t *request_info;
-
- /* Make entries in Protocol column on summary display */
- col_set_str(pinfo->cinfo, COL_PROTOCOL, "Modbus/TCP");
- col_clear(pinfo->cinfo, COL_INFO);
transaction_id = tvb_get_ntohs(tvb, 0);
protocol_id = tvb_get_ntohs(tvb, 2);
unit_id = tvb_get_guint8(tvb, 6);
function_code = tvb_get_guint8(tvb, 7) & 0x7F;
- /* Make entries in Info column on summary display */
offset = 0;
+ /* "Request" or "Response" */
+ packet_type = classify_mbtcp_packet(pinfo, port);
+
+ switch ( packet_type ) {
+ case QUERY_PACKET :
+ pkt_type_str="Query";
+ break;
+ case RESPONSE_PACKET :
+ pkt_type_str="Response";
+ break;
+ case CANNOT_CLASSIFY :
+ err_str="Unable to classify as query or response.";
+ pkt_type_str="unknown";
+ break;
+ default :
+ break;
+ }
+
/* Find exception - last bit set in function code */
if (tvb_get_guint8(tvb, 7) & 0x80) {
exception_code = tvb_get_guint8(tvb, offset + 8);
subfunction_code = 0;
}
- /* "Request" or "Response" */
- packet_type = classify_mbtcp_packet(pinfo);
-
- switch ( packet_type ) {
- case QUERY_PACKET :
- pkt_type_str="Query";
- break;
- case RESPONSE_PACKET :
- pkt_type_str="Response";
- break;
- case CANNOT_CLASSIFY :
- err_str="Unable to classify as query or response.";
- pkt_type_str="unknown";
- break;
- default :
- break;
- }
if ( exception_code != 0 )
err_str="Exception returned ";
+ /* Make entries in Info column on summary display */
if (subfunction_code == 0) {
if (strlen(err_str) > 0) {
col_add_fstr(pinfo->cinfo, COL_INFO,
}
}
- mi = proto_tree_add_protocol_format(tree, proto_mbtcp, tvb, offset,
- len+6, "Modbus/TCP");
+ /* Create protocol tree */
+ mi = proto_tree_add_item(tree, proto, tvb, offset, len+6, ENC_NA);
mbtcp_tree = proto_item_add_subtree(mi, ett_mbtcp);
+ if (packet_type == CANNOT_CLASSIFY)
+ expert_add_info(pinfo, mi, &ei_mbtcp_cannot_classify);
+
/* Add items to protocol tree specific to Modbus/TCP */
proto_tree_add_uint(mbtcp_tree, hf_mbtcp_transid, tvb, offset, 2, transaction_id);
proto_tree_add_uint(mbtcp_tree, hf_mbtcp_protid, tvb, offset + 2, 2, protocol_id);
proto_tree_add_uint(mbtcp_tree, hf_mbtcp_unitid, tvb, offset + 6, 1, unit_id);
/* dissect the Modbus PDU */
- next_tvb = tvb_new_subset( tvb, offset+7, len-1, len-1);
+ next_tvb = tvb_new_subset_length( tvb, offset+7, len-1);
- /* keep existing context */
- p_save_proto_data = p_get_proto_data( pinfo->fd, proto_modbus, 0 );
- p_remove_proto_data(pinfo->fd, proto_modbus, 0);
+ /* Continue with dissection of Modbus data payload following Modbus/TCP frame */
+ if( tvb_reported_length_remaining(tvb, offset) > 0 )
+ call_dissector_with_data(modbus_handle, next_tvb, pinfo, tree, &packet_type);
- /* Create enough context for Modbus dissector */
- request_info = wmem_new(wmem_packet_scope(), modbus_request_info_t);
- request_info->packet_type = (guint8)packet_type;
- request_info->register_addr_type = (guint8)global_mbus_tcp_register_addr_type;
- request_info->register_format = (guint8)global_mbus_tcp_register_format;
- p_add_proto_data(pinfo->fd, proto_modbus, 0, request_info);
+ return tvb_captured_length(tvb);
+}
- /* Continue with dissection of Modbus data payload following Modbus/TCP frame */
- if( tvb_length_remaining(tvb, offset) > 0 )
- call_dissector(modbus_handle, next_tvb, pinfo, tree);
+static int
+dissect_mbtcp_pdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
+{
+ /* Make entries in Protocol column on summary display */
+ col_set_str(pinfo->cinfo, COL_PROTOCOL, "Modbus/TCP");
+ col_clear(pinfo->cinfo, COL_INFO);
- p_remove_proto_data(pinfo->fd, proto_modbus, 0);
- p_add_proto_data(pinfo->fd, proto_modbus, 0, p_save_proto_data);
- return tvb_length(tvb);
+ return dissect_mbtcp_pdu_common(tvb, pinfo, tree, proto_mbtcp, global_mbus_tcp_port);
}
-/* Code to dissect Modbus RTU over TCP packets */
+/* Code to dissect Modbus RTU */
static int
-dissect_mbrtu_pdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
+dissect_mbrtu_pdu_common(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, guint port)
{
/* Set up structures needed to add the protocol subtree and manage it */
- proto_item *mi, *crc_item;
+ proto_item *mi;
proto_tree *mbrtu_tree;
- gint offset, packet_type;
+ int offset, packet_type;
tvbuff_t *next_tvb;
const char *func_string = "";
const char *pkt_type_str = "";
const char *err_str = "";
- guint16 len, crc16, calc_crc16;
+ guint16 len, calc_crc16;
guint8 unit_id, function_code, exception_code, subfunction_code;
- void *p_save_proto_data;
- modbus_request_info_t *request_info;
/* Make entries in Protocol column on summary display */
col_set_str(pinfo->cinfo, COL_PROTOCOL, "Modbus RTU");
col_clear(pinfo->cinfo, COL_INFO);
- len = tvb_length(tvb);
+ len = tvb_reported_length(tvb);
unit_id = tvb_get_guint8(tvb, 0);
function_code = tvb_get_guint8(tvb, 1) & 0x7F;
- crc16 = tvb_get_ntohs(tvb, len-2);
- /* Make entries in Info column on summary display */
offset = 0;
+ /* "Request" or "Response" */
+ packet_type = classify_mbrtu_packet(pinfo, tvb, port);
+
+ switch ( packet_type ) {
+ case QUERY_PACKET :
+ pkt_type_str="Query";
+ break;
+ case RESPONSE_PACKET :
+ pkt_type_str="Response";
+ break;
+ case CANNOT_CLASSIFY :
+ err_str="Unable to classify as query or response.";
+ pkt_type_str="unknown";
+ break;
+ default :
+ break;
+ }
+
/* Find exception - last bit set in function code */
if (tvb_get_guint8(tvb, 1) & 0x80) {
exception_code = tvb_get_guint8(tvb, offset + 2);
subfunction_code = 0;
}
- /* "Request" or "Response" */
- packet_type = classify_mbrtu_packet(pinfo, tvb);
-
- switch ( packet_type ) {
- case QUERY_PACKET :
- pkt_type_str="Query";
- break;
- case RESPONSE_PACKET :
- pkt_type_str="Response";
- break;
- case CANNOT_CLASSIFY :
- err_str="Unable to classify as query or response.";
- pkt_type_str="unknown";
- break;
- default :
- break;
- }
if ( exception_code != 0 )
err_str="Exception returned ";
+ /* Make entries in Info column on summary display */
if (subfunction_code == 0) {
if (strlen(err_str) > 0) {
col_add_fstr(pinfo->cinfo, COL_INFO,
}
}
+ /* Create protocol tree */
mi = proto_tree_add_protocol_format(tree, proto_mbrtu, tvb, offset,
len, "Modbus RTU");
mbrtu_tree = proto_item_add_subtree(mi, ett_mbrtu);
/* Add items to protocol tree specific to Modbus RTU */
proto_tree_add_uint(mbrtu_tree, hf_mbrtu_unitid, tvb, offset, 1, unit_id);
- crc_item = proto_tree_add_uint(mbrtu_tree, hf_mbrtu_crc16, tvb, len-2, 2, crc16);
/* CRC validation */
if (mbrtu_crc)
{
calc_crc16 = crc16_plain_tvb_offset_seed(tvb, offset, len-2, 0xFFFF);
- if (g_htons(calc_crc16) != crc16)
- expert_add_info_format(pinfo, crc_item, &ei_mbrtu_crc16_incorrect, "Incorrect CRC - should be 0x%04x", g_htons(calc_crc16));
+ proto_tree_add_checksum(mbrtu_tree, tvb, len-2, hf_mbrtu_crc16, hf_mbrtu_crc16_status, &ei_mbrtu_crc16_incorrect, pinfo, g_htons(calc_crc16), ENC_BIG_ENDIAN, PROTO_CHECKSUM_VERIFY);
+ }
+ else
+ {
+ proto_tree_add_checksum(mbrtu_tree, tvb, len-2, hf_mbrtu_crc16, hf_mbrtu_crc16_status, &ei_mbrtu_crc16_incorrect, pinfo, 0, ENC_BIG_ENDIAN, PROTO_CHECKSUM_NO_FLAGS);
}
- /* make sure to ignore the CRC-16 footer bytes */
- len = len - 2;
+ /* when determining payload length, make sure to ignore the unit ID header & CRC-16 footer bytes */
+ len = len - 3;
/* dissect the Modbus PDU */
- next_tvb = tvb_new_subset( tvb, offset+1, len-1, len-1);
-
- /* keep existing context */
- p_save_proto_data = p_get_proto_data( pinfo->fd, proto_modbus, 0 );
- p_remove_proto_data(pinfo->fd, proto_modbus, 0);
-
- /* Create enough context for Modbus dissector */
- request_info = wmem_new(wmem_packet_scope(), modbus_request_info_t);
- request_info->packet_type = (guint8)packet_type;
- request_info->register_addr_type = (guint8)global_mbus_rtu_register_addr_type;
- request_info->register_format = (guint8)global_mbus_rtu_register_format;
- p_add_proto_data(pinfo->fd, proto_modbus, 0, request_info);
+ next_tvb = tvb_new_subset_length( tvb, offset+1, len);
/* Continue with dissection of Modbus data payload following Modbus RTU frame */
- if( tvb_length_remaining(tvb, offset) > 0 )
- call_dissector(modbus_handle, next_tvb, pinfo, tree);
+ if( tvb_reported_length_remaining(tvb, offset) > 0 )
+ call_dissector_with_data(modbus_handle, next_tvb, pinfo, tree, &packet_type);
- p_remove_proto_data(pinfo->fd, proto_modbus, 0);
- p_add_proto_data(pinfo->fd, proto_modbus, 0, p_save_proto_data);
- return tvb_length(tvb);
+ return tvb_captured_length(tvb);
}
+/* Code to dissect Modbus RTU over TCP packets */
+static int
+dissect_mbrtu_pdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
+{
+ return dissect_mbrtu_pdu_common(tvb, pinfo, tree, global_mbus_tcp_rtu_port);
+}
/* Return length of Modbus/TCP message */
static guint
-get_mbtcp_pdu_len(packet_info *pinfo _U_, tvbuff_t *tvb, int offset)
+get_mbtcp_pdu_len(packet_info *pinfo _U_, tvbuff_t *tvb, int offset, void *data _U_)
{
guint16 plen;
/* Return length of Modbus RTU over TCP message */
static guint
-get_mbrtu_pdu_len(packet_info *pinfo _U_, tvbuff_t *tvb, int offset _U_)
+get_mbrtu_pdu_len(packet_info *pinfo _U_, tvbuff_t *tvb,
+ int offset _U_, void *data _U_)
{
+ int packet_type;
+ guint8 function_code;
+
+ function_code = tvb_get_guint8(tvb, 1);
+
+ /* Modbus RTU requests do not contain a length field but they are typically a consistent size.
+ Responses do contain a usable 'length' byte at offset 2
+ XXX - Note that only some function codes are supported by this lookup function;
+ the rest can be added as pcap examples are made available */
+
+ /* Determine "Query" or "Response" */
+ packet_type = classify_mbrtu_packet(pinfo, tvb, global_mbus_tcp_rtu_port);
+
+ switch ( packet_type ) {
+ case QUERY_PACKET :
+ switch (function_code) {
+ case READ_COILS: /* Query messages of these types are always 8 bytes */
+ case READ_DISCRETE_INPUTS:
+ case READ_HOLDING_REGS:
+ case READ_INPUT_REGS:
+ case WRITE_SINGLE_COIL:
+ case WRITE_SINGLE_REG:
+ return 8;
+ break;
+ case WRITE_MULT_REGS:
+ case WRITE_MULT_COILS:
+ return tvb_get_guint8(tvb, 6) + 9; /* Reported size does not include 2 header, 4 FC15/16-specific, 1 size byte or 2 CRC16 bytes */
+ break;
+ default :
+ return tvb_captured_length(tvb); /* Fall back on tvb length */
+ break;
+ }
+ case RESPONSE_PACKET :
+ /* The 'exception' bit is set, so this is a 5-byte response */
+ if (function_code & 0x80) {
+ return 5;
+ }
+
+ switch (function_code) {
+ case READ_COILS:
+ case READ_DISCRETE_INPUTS:
+ case READ_HOLDING_REGS:
+ case READ_INPUT_REGS:
+ case WRITE_SINGLE_COIL:
+ case WRITE_SINGLE_REG:
+ return tvb_get_guint8(tvb, 2) + 5; /* Reported size does not include 2 header, 1 size byte, 2 CRC16 bytes */
+ break;
+ case WRITE_MULT_REGS: /* Response messages of FC15/16 are always 8 bytes */
+ case WRITE_MULT_COILS:
+ return 8;
+ break;
+ default :
+ return tvb_captured_length(tvb); /* Fall back on tvb length */
+ break;
+ }
+ case CANNOT_CLASSIFY :
+ default :
+ return tvb_captured_length(tvb); /* Fall back on tvb length */
+ break;
+ }
- /* Modbus/TCP frames include a "length" word in each message; Modbus RTU over TCP does not, so don't attempt to get one */
- return tvb_length(tvb);
}
tcp_dissect_pdus(tvb, pinfo, tree, mbtcp_desegment, 6,
get_mbtcp_pdu_len, dissect_mbtcp_pdu, data);
- return tvb_length(tvb);
+ return tvb_captured_length(tvb);
+}
+
+static int
+dissect_mbudp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
+{
+
+ /* Make sure there's at least enough data to determine it's a Modbus UDP packet */
+ if (!tvb_bytes_exist(tvb, 0, 8))
+ return 0;
+
+ /* check that it actually looks like Modbus/TCP */
+ /* protocol id == 0 */
+ if(tvb_get_ntohs(tvb, 2) != 0 ){
+ return 0;
+ }
+ /* length is at least 2 (unit_id + function_code) */
+ if(tvb_get_ntohs(tvb, 4) < 2 ){
+ return 0;
+ }
+
+ /* Make entries in Protocol column on summary display */
+ col_set_str(pinfo->cinfo, COL_PROTOCOL, "Modbus/UDP");
+ col_clear(pinfo->cinfo, COL_INFO);
+
+ return dissect_mbtcp_pdu_common(tvb, pinfo, tree, proto_mbudp, global_mbus_udp_port);
}
/* Code to dissect Modbus RTU over TCP messages */
{
/* Make sure there's at least enough data to determine it's a Modbus packet */
- if (!tvb_bytes_exist(tvb, 0, 6))
+ /* 5 bytes is the smallest possible valid message (exception response) */
+ if (!tvb_bytes_exist(tvb, 0, 5))
return 0;
/* For Modbus RTU mode, confirm that the first byte is a valid address (non-zero), */
return 0;
/* build up protocol tree and iterate over multiple packets */
- tcp_dissect_pdus(tvb, pinfo, tree, mbrtu_desegment, 6,
+ tcp_dissect_pdus(tvb, pinfo, tree, mbrtu_desegment, 5,
get_mbrtu_pdu_len, dissect_mbrtu_pdu, data);
- return tvb_length(tvb);
+ return tvb_captured_length(tvb);
+}
+
+static int
+dissect_mbrtu_udp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
+{
+
+ /* Make sure there's at least enough data to determine it's a Modbus packet */
+ /* 5 bytes is the smallest possible valid message (exception response) */
+ if (tvb_reported_length(tvb) < 5)
+ return 0;
+
+ return dissect_mbrtu_pdu_common(tvb, pinfo, tree, global_mbus_udp_rtu_port);
}
/* Common to both Modbus/TCP and Modbus RTU dissectors */
static void
dissect_modbus_data(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, guint8 function_code,
- gint payload_start, gint payload_len, guint8 register_format)
+ gint payload_start, gint payload_len, gint register_format, guint16 reg_base)
{
- gint reported_len, data_offset, reg_num = 0;
- guint16 data16, modflt_lo, modflt_hi;
+ gint reported_len, data_offset;
+ gint16 data16s;
+ gint32 data32s;
+ guint16 data16, modflt_lo, modflt_hi, reg_num=reg_base;
guint32 data32, modflt_comb;
gfloat data_float, modfloat;
proto_item *register_item = NULL;
/* AND */
/* if payload length is not a multiple of 4, don't attempt to decode anything in 32-bit format */
if ((function_code == READ_HOLDING_REGS) || (function_code == READ_INPUT_REGS) || (function_code == WRITE_MULT_REGS)) {
- if ((payload_len % 4 != 0) && ( (register_format == MBTCP_PREF_REGISTER_FORMAT_UINT32) ||
- (register_format == MBTCP_PREF_REGISTER_FORMAT_IEEE_FLOAT) ||
- (register_format == MBTCP_PREF_REGISTER_FORMAT_MODICON_FLOAT) ) ) {
+ if ((payload_len % 4 != 0) && ( (register_format == MODBUS_PREF_REGISTER_FORMAT_UINT32) ||
+ (register_format == MODBUS_PREF_REGISTER_FORMAT_IEEE_FLOAT) ||
+ (register_format == MODBUS_PREF_REGISTER_FORMAT_MODICON_FLOAT) ) ) {
register_item = proto_tree_add_item(tree, hf_modbus_data, tvb, payload_start, payload_len, ENC_NA);
expert_add_info(pinfo, register_item, &ei_modbus_data_decode);
return;
}
/* Build a new tvb containing just the data payload */
- next_tvb = tvb_new_subset(tvb, payload_start, payload_len, reported_len);
+ next_tvb = tvb_new_subset_length_caplen(tvb, payload_start, payload_len, reported_len);
switch ( function_code ) {
/* Based on a standard register size of 16-bits, use decoding format preference to step through each register and display */
/* it in an appropriate fashion. */
switch (register_format) {
- case MBTCP_PREF_REGISTER_FORMAT_UINT16: /* Standard-size unsigned integer 16-bit register */
+ case MODBUS_PREF_REGISTER_FORMAT_UINT16: /* Standard-size unsigned integer 16-bit register */
data16 = tvb_get_ntohs(next_tvb, data_offset);
- register_item = proto_tree_add_uint(tree, hf_modbus_reg_uint16, next_tvb, data_offset, 2, data16);
- proto_item_set_text(register_item, "Register %u (UINT16): %u", reg_num, data16);
-
+ proto_tree_add_uint_format(tree, hf_modbus_reg16, next_tvb, data_offset, 2, reg_num,
+ "Register %u (UINT16): %u", reg_num, data16);
data_offset += 2;
reg_num += 1;
break;
- case MBTCP_PREF_REGISTER_FORMAT_UINT32: /* Double-size unsigned integer 2 x 16-bit registers */
+ case MODBUS_PREF_REGISTER_FORMAT_INT16: /* Standard-size signed integer 16-bit register */
+ data16s = tvb_get_ntohs(next_tvb, data_offset);
+ proto_tree_add_uint_format(tree, hf_modbus_reg16, next_tvb, data_offset, 2, reg_num,
+ "Register %u (INT16): %d", reg_num, data16s);
+ data_offset += 2;
+ reg_num += 1;
+ break;
+ case MODBUS_PREF_REGISTER_FORMAT_UINT32: /* Double-size unsigned integer 2 x 16-bit registers */
data32 = tvb_get_ntohl(next_tvb, data_offset);
- register_item = proto_tree_add_uint(tree, hf_modbus_reg_uint32, next_tvb, data_offset, 4, data32);
- proto_item_set_text(register_item, "Register %u (UINT32): %u", reg_num, data32);
-
+ proto_tree_add_uint_format(tree, hf_modbus_reg32, next_tvb, data_offset, 4, reg_num,
+ "Register %u (UINT32): %u", reg_num, data32);
data_offset += 4;
reg_num += 2;
break;
- case MBTCP_PREF_REGISTER_FORMAT_IEEE_FLOAT: /* IEEE Floating Point, 2 x 16-bit registers */
+ case MODBUS_PREF_REGISTER_FORMAT_INT32: /* Double-size signed integer 2 x 16-bit registers */
+ data32s = tvb_get_ntohl(next_tvb, data_offset);
+ proto_tree_add_uint_format(tree, hf_modbus_reg32, next_tvb, data_offset, 4, reg_num,
+ "Register %u (INT32): %d", reg_num, data32s);
+ data_offset += 4;
+ reg_num += 2;
+ break;
+ case MODBUS_PREF_REGISTER_FORMAT_IEEE_FLOAT: /* IEEE Floating Point, 2 x 16-bit registers */
data_float = tvb_get_ntohieee_float(next_tvb, data_offset);
- register_item = proto_tree_add_float(tree, hf_modbus_reg_ieee_float, next_tvb, data_offset, 4, data_float);
- proto_item_set_text(register_item, "Register %u (IEEE Float): %f", reg_num, data_float);
+ proto_tree_add_uint_format(tree, hf_modbus_reg32, next_tvb, data_offset, 4, reg_num,
+ "Register %u (IEEE Float): %f", reg_num, data_float);
data_offset += 4;
reg_num += 2;
break;
- case MBTCP_PREF_REGISTER_FORMAT_MODICON_FLOAT: /* Modicon Floating Point (word-swap), 2 x 16-bit registers */
+ case MODBUS_PREF_REGISTER_FORMAT_MODICON_FLOAT: /* Modicon Floating Point (word-swap), 2 x 16-bit registers */
/* Modicon-style Floating Point values are stored in reverse-word order. */
/* ie: a standard IEEE float value 59.991459 is equal to 0x426ff741 */
/* while the Modicon equivalent to this value is 0xf741426f */
/* "hi" component by 16-bits and then OR them together into a combined 32-bit int. */
/* Following that operation, use some memcpy magic to copy the 4 raw data bytes from the */
/* 32-bit integer into a standard float. Not sure if there is a cleaner way possible using */
- /* the Wireshark libaries, but this seems to work OK. */
+ /* the Wireshark libraries, but this seems to work OK. */
modflt_lo = tvb_get_ntohs(next_tvb, data_offset);
modflt_hi = tvb_get_ntohs(next_tvb, data_offset+2);
modflt_comb = (guint32)(modflt_hi<<16) | modflt_lo;
memcpy(&modfloat, &modflt_comb, 4);
- register_item = proto_tree_add_float(tree, hf_modbus_reg_modicon_float, next_tvb, data_offset, 4, modfloat);
- proto_item_set_text(register_item, "Register %u (Modicon Float): %f", reg_num, modfloat);
-
+ proto_tree_add_uint_format(tree, hf_modbus_reg32, next_tvb, data_offset, 4, reg_num,
+ "Register %u (Modicon Float): %f", reg_num, modfloat);
data_offset += 4;
reg_num += 2;
break;
}
}
-/* Code to actually dissect the packets */
+/* Code to dissect Modbus request message */
static int
-dissect_modbus(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_)
+dissect_modbus_request(tvbuff_t *tvb, packet_info *pinfo, proto_tree *modbus_tree, guint8 function_code, gint payload_start, gint payload_len)
{
- 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 = 0, group_offset;
- gint payload_start, payload_len, event_index,
- ii, byte_cnt, len, num_objects, object_index,
- object_len;
+ proto_tree *group_tree;
+ gint byte_cnt, group_offset, ii;
+ gint register_format = MODBUS_PREF_REGISTER_FORMAT_UINT16; /* Default value for register formatting.. */
+ guint8 mei_code;
+ guint16 reg_base=0, diagnostic_code;
guint32 group_byte_cnt, group_word_cnt;
- guint8 function_code, exception_code, mei_code, event_code, object_type;
- guint8 packet_type, register_format; /*register_addr_type*/
- guint16 diagnostic_code;
- modbus_request_info_t *request_info;
- /* Don't need to do anything if there's no tree */
- if (tree == NULL)
- return tvb_length(tvb);
+ modbus_conversation *conv;
- len = tvb_length_remaining(tvb, 0);
+ /* See if we have any context */
+ conv = (modbus_conversation *)p_get_proto_data(wmem_file_scope(), pinfo, proto_modbus, 0);
- /* If the packet is zero-length, we should not attempt to dissect any further */
- if (len == 0)
- return 0;
+ if (conv) {
+ register_format = conv->register_format;
+ }
- function_code = tvb_get_guint8(tvb, offset) & 0x7F;
+ switch (function_code) {
- /* Find exception - last bit set in function code */
- if (tvb_get_guint8(tvb, offset) & 0x80 ) {
- exception_code = tvb_get_guint8(tvb, offset+1);
- }
- else {
- exception_code = 0;
- }
+ case READ_COILS:
+ case READ_DISCRETE_INPUTS:
+ 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;
- /* See if we have any context */
- request_info = (modbus_request_info_t *)p_get_proto_data( pinfo->fd, proto_modbus, 0 );
- if (request_info != NULL)
- {
- packet_type = request_info->packet_type;
- register_format = request_info->register_format;
- /*register_addr_type = request_info->register_addr_type;*/
- }
- else
- {
- /* Default to a response packet to at least attempt to decode a good chunk of data */
- packet_type = RESPONSE_PACKET;
- register_format = MBTCP_PREF_REGISTER_FORMAT_UINT16;
- /* register_addr_type = MBTCP_PREF_REGISTER_ADDR_RAW;*/
- }
+ case READ_HOLDING_REGS:
+ case READ_INPUT_REGS:
+ 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;
- /* 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);
+ case WRITE_SINGLE_COIL:
+ proto_tree_add_item(modbus_tree, hf_modbus_reference, tvb, payload_start, 2, ENC_BIG_ENDIAN);
+ dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start + 2, 1, register_format, reg_base);
+ proto_tree_add_item(modbus_tree, hf_modbus_padding, tvb, payload_start + 3, 1, ENC_NA);
+ break;
- mi = proto_tree_add_uint(modbus_tree, hf_mbtcp_functioncode, tvb, offset, 1,
- function_code);
+ case WRITE_SINGLE_REG:
+ proto_tree_add_item(modbus_tree, hf_modbus_reference, tvb, payload_start, 2, ENC_BIG_ENDIAN);
+ dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start + 2, 2, register_format, reg_base);
+ break;
- payload_start = offset + 1;
- payload_len = len - 1;
- if (exception_code != 0) {
- proto_item_set_text(mi, "Function %u: %s. Exception: %s",
- function_code,
- val_to_str_const(function_code, function_code_vals, "Unknown Function"),
- 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 {
- switch (function_code) {
+ case READ_EXCEPT_STAT:
+ /* Do Nothing */
+ break;
- case READ_COILS:
- case READ_DISCRETE_INPUTS:
+ case DIAGNOSTICS:
+ 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 (payload_len > 2)
+ proto_tree_add_item(modbus_tree, hf_modbus_diag_return_query_data_request, tvb, payload_start+2, payload_len-2, ENC_NA);
+ break;
+ case RESTART_COMMUNICATION_OPTION:
+ proto_tree_add_item(modbus_tree, hf_modbus_diag_restart_communication_option, tvb, payload_start+2, 2, ENC_BIG_ENDIAN);
+ break;
+ case CHANGE_ASCII_INPUT_DELIMITER:
+ proto_tree_add_item(modbus_tree, hf_modbus_diag_ascii_input_delimiter, tvb, payload_start+2, 1, ENC_BIG_ENDIAN);
+ break;
+ case RETURN_DIAGNOSTIC_REGISTER: /* 00 00 Data Field */
+ case FORCE_LISTEN_ONLY_MODE: /* 00 00 Data Field */
+ case CLEAR_COUNTERS_AND_DIAG_REG: /* 00 00 Data Field */
+ case RETURN_BUS_MESSAGE_COUNT: /* 00 00 Data Field */
+ case RETURN_BUS_COMM_ERROR_COUNT: /* 00 00 Data Field */
+ case RETURN_BUS_EXCEPTION_ERROR_COUNT: /* 00 00 Data Field */
+ case RETURN_SLAVE_MESSAGE_COUNT: /* 00 00 Data Field */
+ case RETURN_SLAVE_NO_RESPONSE_COUNT: /* 00 00 Data Field */
+ case RETURN_SLAVE_NAK_COUNT: /* 00 00 Data Field */
+ case RETURN_SLAVE_BUSY_COUNT: /* 00 00 Data Field */
+ case RETURN_BUS_CHAR_OVERRUN_COUNT: /* 00 00 Data Field */
+ case CLEAR_OVERRUN_COUNTER_AND_FLAG:
+ default:
+ if (payload_len > 2)
+ dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start+2, payload_len-2, register_format, reg_base);
+ break;
+ }
+ break;
+ case WRITE_MULT_COILS:
+ 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_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start + 5, byte_cnt, register_format, reg_base);
+ break;
- 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_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start + 1, byte_cnt, register_format);
- }
- break;
+ case WRITE_MULT_REGS:
+ reg_base = tvb_get_ntohs(tvb, payload_start);
+ 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_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start + 5, byte_cnt, register_format, reg_base);
+ break;
- case READ_HOLDING_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_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start + 1, byte_cnt, register_format);
- }
- break;
+ case READ_FILE_RECORD:
+ 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 (ii = 0; ii < byte_cnt / 7; ii++) {
+ group_tree = proto_tree_add_subtree_format( modbus_tree, tvb, group_offset, 7,
+ ett_group_hdr, NULL, "Group %u", ii);
+ 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;
+ }
+ break;
- case WRITE_SINGLE_COIL:
- if (packet_type == QUERY_PACKET) {
- proto_tree_add_item(modbus_tree, hf_modbus_reference, tvb, payload_start, 2, ENC_BIG_ENDIAN);
- dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start + 2, 1, register_format);
- 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_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start + 2, 1, register_format);
- proto_tree_add_text(modbus_tree, tvb, payload_start + 3, 1, "Padding");
- }
- break;
+ case WRITE_FILE_RECORD:
+ 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;
+ ii = 0;
+ while (byte_cnt > 0) {
+ group_word_cnt = tvb_get_ntohs(tvb, group_offset + 5);
+ group_byte_cnt = (2 * group_word_cnt) + 7;
+ group_tree = proto_tree_add_subtree_format( modbus_tree, tvb, group_offset,
+ group_byte_cnt, ett_group_hdr, NULL, "Group %u", ii);
+ 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_modbus_data(tvb, pinfo, group_tree, function_code, group_offset + 7, group_byte_cnt - 7, register_format, reg_base);
+ group_offset += group_byte_cnt;
+ byte_cnt -= group_byte_cnt;
+ ii++;
+ }
+ 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_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start + 2, 2, register_format);
- }
- else if (packet_type == RESPONSE_PACKET) {
- proto_tree_add_item(modbus_tree, hf_modbus_reference, tvb, payload_start, 2, ENC_BIG_ENDIAN);
- dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start + 2, 2, register_format);
- }
- break;
+ case MASK_WRITE_REG:
+ 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_EXCEPT_STAT:
- if (packet_type == RESPONSE_PACKET)
- dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start, 1, register_format);
- break;
+ case READ_WRITE_REG:
+ 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_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start + 9, byte_cnt, register_format, reg_base);
+ 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_item(modbus_tree, hf_modbus_diag_return_query_data_request, tvb, payload_start+2, payload_len-2, ENC_NA);
- }
- else if (packet_type == RESPONSE_PACKET) {
- if (payload_len > 2)
- proto_tree_add_item(modbus_tree, hf_modbus_diag_return_query_data_echo, tvb, payload_start+2, payload_len-2, ENC_NA);
- }
- break;
- case RESTART_COMMUNICATION_OPTION:
- proto_tree_add_item(modbus_tree, hf_modbus_diag_restart_communication_option, tvb, payload_start+2, 2, ENC_BIG_ENDIAN);
- break;
- case RETURN_DIAGNOSTIC_REGISTER:
- if (packet_type == QUERY_PACKET) {
- if (payload_len > 2)
- dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start+2, payload_len-2, register_format);
- }
- else if (packet_type == RESPONSE_PACKET) {
- proto_tree_add_item(modbus_tree, hf_modbus_diag_return_diag_register, tvb, payload_start+2, 2, ENC_BIG_ENDIAN);
- }
- break;
- case CHANGE_ASCII_INPUT_DELIMITER:
- proto_tree_add_item(modbus_tree, hf_modbus_diag_ascii_input_delimiter, tvb, payload_start+2, 1, ENC_BIG_ENDIAN);
- break;
- case RETURN_BUS_MESSAGE_COUNT:
- if (packet_type == QUERY_PACKET) {
- if (payload_len > 2)
- dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start+2, payload_len-2, register_format);
- }
- else if (packet_type == RESPONSE_PACKET) {
- proto_tree_add_item(modbus_tree, hf_modbus_diag_return_bus_message_count, tvb, payload_start+2, 2, ENC_BIG_ENDIAN);
- }
- break;
- case RETURN_BUS_COMM_ERROR_COUNT:
- if (packet_type == QUERY_PACKET) {
- if (payload_len > 2)
- dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start+2, payload_len-2, register_format);
- }
- else if (packet_type == RESPONSE_PACKET) {
- proto_tree_add_item(modbus_tree, hf_modbus_diag_return_bus_comm_error_count, tvb, payload_start+2, 2, ENC_BIG_ENDIAN);
- }
- break;
- case RETURN_BUS_EXCEPTION_ERROR_COUNT:
- if (packet_type == QUERY_PACKET) {
- if (payload_len > 2)
- dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start+2, payload_len-2, register_format);
- }
- else if (packet_type == RESPONSE_PACKET) {
- proto_tree_add_item(modbus_tree, hf_modbus_diag_return_bus_exception_error_count, tvb, payload_start+2, 2, ENC_BIG_ENDIAN);
- }
- break;
- case RETURN_SLAVE_MESSAGE_COUNT:
- if (packet_type == QUERY_PACKET) {
- if (payload_len > 2)
- dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start+2, payload_len-2, register_format);
- }
- else if (packet_type == RESPONSE_PACKET) {
- proto_tree_add_item(modbus_tree, hf_modbus_diag_return_slave_message_count, tvb, payload_start+2, 2, ENC_BIG_ENDIAN);
- }
- break;
- case RETURN_SLAVE_NO_RESPONSE_COUNT:
- if (packet_type == QUERY_PACKET) {
- if (payload_len > 2)
- dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start+2, payload_len-2, register_format);
- }
- else if (packet_type == RESPONSE_PACKET) {
- proto_tree_add_item(modbus_tree, hf_modbus_diag_return_no_slave_response_count, tvb, payload_start+2, 2, ENC_BIG_ENDIAN);
- }
- break;
- case RETURN_SLAVE_NAK_COUNT:
- if (packet_type == QUERY_PACKET) {
- if (payload_len > 2)
- dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start+2, payload_len-2, register_format);
- }
- else if (packet_type == RESPONSE_PACKET) {
- proto_tree_add_item(modbus_tree, hf_modbus_diag_return_slave_nak_count, tvb, payload_start+2, 2, ENC_BIG_ENDIAN);
- }
- break;
- case RETURN_SLAVE_BUSY_COUNT:
- if (packet_type == QUERY_PACKET) {
- if (payload_len > 2)
- dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start+2, payload_len-2, register_format);
- }
- else if (packet_type == RESPONSE_PACKET) {
- proto_tree_add_item(modbus_tree, hf_modbus_diag_return_slave_busy_count, tvb, payload_start+2, 2, ENC_BIG_ENDIAN);
- }
- break;
- case RETURN_BUS_CHAR_OVERRUN_COUNT:
- if (packet_type == QUERY_PACKET) {
- if (payload_len > 2)
- dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start+2, payload_len-2, register_format);
- }
- else if (packet_type == RESPONSE_PACKET) {
- proto_tree_add_item(modbus_tree, hf_modbus_diag_return_bus_char_overrun_count, tvb, payload_start+2, 2, ENC_BIG_ENDIAN);
- }
- break;
- case CLEAR_OVERRUN_COUNTER_AND_FLAG:
- case FORCE_LISTEN_ONLY_MODE:
- case CLEAR_COUNTERS_AND_DIAG_REG:
- default:
- if (payload_len > 2)
- dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start+2, payload_len-2, register_format);
- break;
- }
- }
- break;
+ case READ_FIFO_QUEUE:
+ proto_tree_add_item(modbus_tree, hf_modbus_reference, tvb, payload_start, 2, ENC_BIG_ENDIAN);
+ 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 ENCAP_INTERFACE_TRANSP:
+ 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_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start, payload_len-1, register_format, reg_base);
+ 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;
+ 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_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start + 5, byte_cnt, register_format);
- }
- 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 REPORT_SLAVE_ID:
+ default:
+ if (payload_len > 0)
+ dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start, payload_len, register_format, reg_base);
+ 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_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start + 5, byte_cnt, register_format);
- }
- 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;
+ } /* Function Code */
- 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 (ii = 0; ii < byte_cnt / 7; ii++) {
- mi = proto_tree_add_text( modbus_tree, tvb, group_offset, 7,
- "Group %u", ii);
- 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;
+ return tvb_captured_length(tvb);
+}
+
+/* Code to dissect Modbus Response message */
+static int
+dissect_modbus_response(tvbuff_t *tvb, packet_info *pinfo, proto_tree *modbus_tree, guint8 function_code, gint payload_start, gint payload_len)
+{
+
+ proto_tree *group_tree, *event_tree, *event_item_tree, *device_objects_tree, *device_objects_item_tree;
+ proto_item *mei;
+ gint byte_cnt, group_offset, event_index, object_index, object_len, num_objects, ii;
+ gint register_format = MODBUS_PREF_REGISTER_FORMAT_UINT16; /* Default value for register formatting.. */
+ guint8 object_type, mei_code, event_code;
+ guint16 reg_base=0, diagnostic_code;
+ guint32 group_byte_cnt, group_word_cnt;
+
+ /* Conversation tracking */
+ proto_item *request_frame_item;
+ modbus_conversation *conv;
+ guint8 req_function_code;
+ guint32 req_frame_num;
+ gboolean request_found = FALSE;
+ modbus_request_info_t *request_data;
+
+ /* See if we have any context */
+ conv = (modbus_conversation *)p_get_proto_data(wmem_file_scope(), pinfo, proto_modbus, 0);
+
+ if (conv) {
+
+ wmem_list_frame_t *frame = wmem_list_head(conv->modbus_request_frame_data);
+ /* Step backward through all logged instances of request frames, looking for a request frame number that
+ occurred immediately prior to current frame number that has a matching function code */
+ while (frame && !request_found) {
+ request_data = (modbus_request_info_t *)wmem_list_frame_data(frame);
+ req_frame_num = request_data->fnum;
+ req_function_code = request_data->function_code;
+ if ((pinfo->num > req_frame_num) && (req_function_code == function_code)) {
+ request_frame_item = proto_tree_add_uint(modbus_tree, hf_modbus_request_frame, tvb, 0, 0, req_frame_num);
+ reg_base = request_data->base_address;
+ PROTO_ITEM_SET_GENERATED(request_frame_item);
+ request_found = TRUE;
+ }
+ frame = wmem_list_frame_next(frame);
+ }
+
+ register_format = conv->register_format;
+ } /* conv */
+
+ switch (function_code) {
+
+ case READ_COILS:
+ case READ_DISCRETE_INPUTS:
+ 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_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start + 1, byte_cnt, register_format, reg_base);
+ break;
+
+ case READ_HOLDING_REGS:
+ case READ_INPUT_REGS:
+ 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_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start + 1, byte_cnt, register_format, reg_base);
+ break;
+
+ case WRITE_SINGLE_COIL:
+ proto_tree_add_item(modbus_tree, hf_modbus_reference, tvb, payload_start, 2, ENC_BIG_ENDIAN);
+ dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start + 2, 1, register_format, reg_base);
+ proto_tree_add_item(modbus_tree, hf_modbus_padding, tvb, payload_start + 3, 1, ENC_NA);
+ break;
+
+ case WRITE_SINGLE_REG:
+ proto_tree_add_item(modbus_tree, hf_modbus_reference, tvb, payload_start, 2, ENC_BIG_ENDIAN);
+ dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start + 2, 2, register_format, reg_base);
+ break;
+
+ case READ_EXCEPT_STAT:
+ dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start, 1, register_format, reg_base);
+ break;
+
+ case DIAGNOSTICS:
+ 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: /* Echo of Request */
+ if (payload_len > 2)
+ proto_tree_add_item(modbus_tree, hf_modbus_diag_return_query_data_echo, tvb, payload_start+2, payload_len-2, ENC_NA);
+ break;
+ case RESTART_COMMUNICATION_OPTION: /* Echo of Request */
+ proto_tree_add_item(modbus_tree, hf_modbus_diag_restart_communication_option, tvb, payload_start+2, 2, ENC_BIG_ENDIAN);
+ break;
+ case RETURN_DIAGNOSTIC_REGISTER:
+ proto_tree_add_item(modbus_tree, hf_modbus_diag_return_diag_register, tvb, payload_start+2, 2, ENC_BIG_ENDIAN);
+ break;
+ case CHANGE_ASCII_INPUT_DELIMITER: /* XXX - Do we expect this to ever be a response? */
+ proto_tree_add_item(modbus_tree, hf_modbus_diag_ascii_input_delimiter, tvb, payload_start+2, 1, ENC_BIG_ENDIAN);
+ break;
+ case CLEAR_COUNTERS_AND_DIAG_REG: /* Echo of Request */
+ proto_tree_add_item(modbus_tree, hf_modbus_diag_clear_ctr_diag_reg, tvb, payload_start+2, 2, ENC_BIG_ENDIAN);
+ break;
+ case RETURN_BUS_MESSAGE_COUNT:
+ proto_tree_add_item(modbus_tree, hf_modbus_diag_return_bus_message_count, tvb, payload_start+2, 2, ENC_BIG_ENDIAN);
+ break;
+ case RETURN_BUS_COMM_ERROR_COUNT:
+ proto_tree_add_item(modbus_tree, hf_modbus_diag_return_bus_comm_error_count, tvb, payload_start+2, 2, ENC_BIG_ENDIAN);
+ break;
+ case RETURN_BUS_EXCEPTION_ERROR_COUNT:
+ proto_tree_add_item(modbus_tree, hf_modbus_diag_return_bus_exception_error_count, tvb, payload_start+2, 2, ENC_BIG_ENDIAN);
+ break;
+ case RETURN_SLAVE_MESSAGE_COUNT:
+ proto_tree_add_item(modbus_tree, hf_modbus_diag_return_slave_message_count, tvb, payload_start+2, 2, ENC_BIG_ENDIAN);
+ break;
+ case RETURN_SLAVE_NO_RESPONSE_COUNT:
+ proto_tree_add_item(modbus_tree, hf_modbus_diag_return_no_slave_response_count, tvb, payload_start+2, 2, ENC_BIG_ENDIAN);
+ break;
+ case RETURN_SLAVE_NAK_COUNT:
+ proto_tree_add_item(modbus_tree, hf_modbus_diag_return_slave_nak_count, tvb, payload_start+2, 2, ENC_BIG_ENDIAN);
+ break;
+ case RETURN_SLAVE_BUSY_COUNT:
+ proto_tree_add_item(modbus_tree, hf_modbus_diag_return_slave_busy_count, tvb, payload_start+2, 2, ENC_BIG_ENDIAN);
+ break;
+ case RETURN_BUS_CHAR_OVERRUN_COUNT:
+ proto_tree_add_item(modbus_tree, hf_modbus_diag_return_bus_char_overrun_count, tvb, payload_start+2, 2, ENC_BIG_ENDIAN);
+ break;
+ case CLEAR_OVERRUN_COUNTER_AND_FLAG: /* Echo of Request */
+ case FORCE_LISTEN_ONLY_MODE: /* No response anticipated */
+ default:
+ if (payload_len > 2)
+ dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start+2, payload_len-2, register_format, reg_base);
+ break;
+ } /* diagnostic_code */
+ break;
+
+ case GET_COMM_EVENT_CTRS:
+ 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:
+ 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;
+ event_tree = proto_tree_add_subtree(modbus_tree, tvb, payload_start+7, byte_cnt, ett_events, NULL, "Events");
+ while (byte_cnt > 0) {
+ event_code = tvb_get_guint8(tvb, payload_start+7+event_index);
+ if (event_code == 0) {
+ proto_tree_add_uint_format(event_tree, hf_modbus_event, tvb, payload_start+7+event_index, 1, event_code, "Initiated Communication Restart");
}
- }
- 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;
- ii = 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", ii);
- 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_modbus_data(tvb, pinfo, group_tree, function_code, group_offset + 2, group_byte_cnt - 1, register_format);
- group_offset += (group_byte_cnt + 1);
- byte_cnt -= (group_byte_cnt + 1);
- ii++;
+ else if (event_code == 4) {
+ proto_tree_add_uint_format(event_tree, hf_modbus_event, tvb, payload_start+7+event_index, 1, event_code, "Entered Listen Only Mode");
}
- }
- 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;
- ii = 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", ii);
- 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_modbus_data(tvb, pinfo, group_tree, function_code, group_offset + 7, group_byte_cnt - 7, register_format);
- group_offset += group_byte_cnt;
- byte_cnt -= group_byte_cnt;
- ii++;
+ else if (event_code & REMOTE_DEVICE_RECV_EVENT_MASK) {
+ mei = proto_tree_add_uint_format(event_tree, hf_modbus_event, tvb, payload_start+7+event_index, 1,
+ event_code, "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_uint_format(event_tree, hf_modbus_event, tvb, payload_start+7+event_index, 1,
+ event_code, "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_uint_format(event_tree, hf_modbus_event, tvb, payload_start+7+event_index, 1, event_code, "Unknown Event");
}
- }
- 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);
+ byte_cnt--;
+ event_index++;
}
- break;
+ }
+ 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_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start + 9, byte_cnt, register_format);
- }
- 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_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start + 1, byte_cnt, register_format);
- }
- break;
+ case WRITE_MULT_COILS:
+ 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 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_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start + 4, byte_cnt - 2, register_format);
- }
- break;
+ case WRITE_MULT_REGS:
+ 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 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_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start, payload_len-1, register_format);
- 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_FILE_RECORD:
+ 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;
+ ii = 0;
+ while (byte_cnt > 0) {
+ group_byte_cnt = (guint32)tvb_get_guint8(tvb, group_offset);
+ group_tree = proto_tree_add_subtree_format( modbus_tree, tvb, group_offset, group_byte_cnt + 1,
+ ett_group_hdr, NULL, "Group %u", ii);
+ 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_modbus_data(tvb, pinfo, group_tree, function_code, group_offset + 2, group_byte_cnt - 1, register_format, reg_base);
+ group_offset += (group_byte_cnt + 1);
+ byte_cnt -= (group_byte_cnt + 1);
+ ii++;
+ }
+ break;
+
+ case WRITE_FILE_RECORD: /* Normal response is echo of request */
+ 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;
+ ii = 0;
+ while (byte_cnt > 0) {
+ group_word_cnt = tvb_get_ntohs(tvb, group_offset + 5);
+ group_byte_cnt = (2 * group_word_cnt) + 7;
+ group_tree = proto_tree_add_subtree_format( modbus_tree, tvb, group_offset,
+ group_byte_cnt, ett_group_hdr, NULL, "Group %u", ii);
+ 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_modbus_data(tvb, pinfo, group_tree, function_code, group_offset + 7, group_byte_cnt - 7, register_format, reg_base);
+ group_offset += group_byte_cnt;
+ byte_cnt -= group_byte_cnt;
+ ii++;
+ }
+ break;
+
+ case MASK_WRITE_REG: /* Normal response is echo of request */
+ 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:
+ 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_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start + 1, byte_cnt, register_format, reg_base);
+ break;
+
+ case READ_FIFO_QUEUE:
+ 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_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start + 4, byte_cnt - 2, register_format, reg_base);
+ break;
+
+ case ENCAP_INTERFACE_TRANSP:
+ 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);
+ device_objects_tree = proto_tree_add_subtree(modbus_tree, tvb, payload_start+6, payload_len-6,
+ ett_device_id_objects, NULL, "Objects");
+
+ object_index = 0;
+ for (ii = 0; ii < num_objects; ii++)
{
- 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 (ii = 0; ii < num_objects; ii++)
- {
- 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", ii+1);
- 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_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start, payload_len-1, register_format);
- break;
- }
- }
- break;
+ /* add each "object item" as its own subtree */
- case REPORT_SLAVE_ID:
- default:
- if (payload_len > 0)
- dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start, payload_len, register_format);
- break;
+ /* 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);
+
+ device_objects_item_tree = proto_tree_add_subtree_format(device_objects_tree, tvb, payload_start+6+object_index, 2+object_len,
+ ett_device_id_object_items, NULL, "Object #%d", ii+1);
+
+ 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_item(device_objects_item_tree, hf_modbus_object_value, tvb, payload_start+6+object_index, object_len, ENC_NA);
+ }
+ object_index += object_len;
+ } /* for ii */
+ break;
+
+ case CANOPEN_REQ_RESP:
+ /* CANopen protocol not part of the Modbus/TCP specification */
+ default:
+ if (payload_len > 1)
+ dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start, payload_len-1, register_format, reg_base);
+ break;
+ } /* mei_code */
+ break;
+
+ case REPORT_SLAVE_ID:
+ default:
+ if (payload_len > 0)
+ dissect_modbus_data(tvb, pinfo, modbus_tree, function_code, payload_start, payload_len, register_format, reg_base);
+ break;
+
+ } /* function code */
+
+ return tvb_captured_length(tvb);
+}
+
+
+/* Dissect the Modbus Payload. Called from either Modbus/TCP or Modbus RTU Dissector */
+static int
+dissect_modbus(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
+{
+ proto_tree *modbus_tree;
+ proto_item *mi;
+ int offset = 0;
+ int* packet_type = (int*)data;
+ gint payload_start, payload_len, len;
+ guint8 function_code, exception_code;
+
+ /* Reject the packet if data passed from the mbrtu or mbtcp dissector is NULL */
+ if (packet_type == NULL)
+ return 0;
+
+ len = tvb_captured_length(tvb);
+
+ /* If the packet is zero-length, we should not attempt to dissect any further */
+ if (len == 0)
+ return 0;
+
+ /* Add items to protocol tree specific to Modbus */
+ mi = proto_tree_add_protocol_format(tree, proto_modbus, tvb, offset, len, "Modbus");
+ modbus_tree = proto_item_add_subtree(mi, ett_modbus_hdr);
+
+ function_code = tvb_get_guint8(tvb, offset) & 0x7F;
+ proto_tree_add_item(modbus_tree, hf_modbus_functioncode, tvb, offset, 1, ENC_BIG_ENDIAN);
+
+ /* Conversation support */
+ if (!pinfo->fd->flags.visited) {
+ conversation_t *conversation = NULL;
+ modbus_conversation *modbus_conv_data = NULL;
+
+ /* Find a conversation, create a new if no one exists */
+ conversation = find_or_create_conversation(pinfo);
+ modbus_conv_data = (modbus_conversation *)conversation_get_proto_data(conversation, proto_modbus);
+
+ if (modbus_conv_data == NULL){
+ modbus_conv_data = wmem_new(wmem_file_scope(), modbus_conversation);
+ modbus_conv_data->modbus_request_frame_data = wmem_list_new(wmem_file_scope());
+ modbus_conv_data->register_format = global_mbus_register_format;
+ conversation_add_proto_data(conversation, proto_modbus, (void *)modbus_conv_data);
}
+
+ p_add_proto_data(wmem_file_scope(), pinfo, proto_modbus, 0, modbus_conv_data);
+
+ if (*packet_type == QUERY_PACKET) {
+ /*create the modbus_request frame. It holds the request information.*/
+ modbus_request_info_t *frame_ptr = wmem_new(wmem_file_scope(), modbus_request_info_t);
+
+ /* load information into the modbus request frame */
+ frame_ptr->fnum = pinfo->num;
+ frame_ptr->function_code = function_code;
+ frame_ptr->base_address = tvb_get_ntohs(tvb, 1);
+ frame_ptr->num_reg = tvb_get_ntohs(tvb, 3);
+
+ wmem_list_prepend(modbus_conv_data->modbus_request_frame_data, frame_ptr);
+ }
+
+ } /* !visited */
+
+ /* Find exception - last bit set in function code */
+ if (tvb_get_guint8(tvb, offset) & 0x80 ) {
+ exception_code = tvb_get_guint8(tvb, offset+1);
+ }
+ else {
+ exception_code = 0;
}
- return tvb_length(tvb);
-}
+ payload_start = offset + 1;
+ payload_len = len - 1;
+
+ if (exception_code != 0) {
+ proto_item_set_text(mi, "Function %u: %s. Exception: %s",
+ function_code,
+ val_to_str_const(function_code, function_code_vals, "Unknown Function"),
+ 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 {
+ /* Follow different dissection path depending on whether packet is query or response */
+ if (*packet_type == QUERY_PACKET) {
+ dissect_modbus_request(tvb, pinfo, modbus_tree, function_code, payload_start, payload_len);
+ }
+ else if (*packet_type == RESPONSE_PACKET) {
+ dissect_modbus_response(tvb, pinfo, modbus_tree, function_code, payload_start, payload_len);
+ }
-/* Register the protocol with Wireshark */
+ }
-void proto_reg_handoff_mbtcp(void);
-void proto_reg_handoff_mbrtu(void);
+ return tvb_captured_length(tvb);
+}
+static void
+apply_mbtcp_prefs(void)
+{
+ /* Modbus/RTU uses the port preference to determine request/response */
+ global_mbus_tcp_port = prefs_get_uint_value("mbtcp", "tcp.port");
+ global_mbus_udp_port = prefs_get_uint_value("mbudp", "udp.port");
+}
+
+static void
+apply_mbrtu_prefs(void)
+{
+ /* Modbus/RTU uses the port preference to determine request/response */
+ global_mbus_tcp_rtu_port = prefs_get_uint_value("mbrtu", "tcp.port");
+ global_mbus_udp_rtu_port = prefs_get_uint_value("mbrtu", "udp.port");
+}
+
+/* Register the protocol with Wireshark */
void
proto_register_modbus(void)
{
/* Modbus/TCP header fields */
static hf_register_info mbtcp_hf[] = {
{ &hf_mbtcp_transid,
- { "Transaction Identifier", "mbtcp.trans_id",
+ { "Transaction Identifier", "mbtcp.trans_id",
FT_UINT16, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_mbtcp_protid,
- { "Protocol Identifier", "mbtcp.prot_id",
+ { "Protocol Identifier", "mbtcp.prot_id",
FT_UINT16, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_mbtcp_len,
- { "Length", "mbtcp.len",
+ { "Length", "mbtcp.len",
FT_UINT16, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_mbtcp_unitid,
- { "Unit Identifier", "mbtcp.unit_id",
+ { "Unit Identifier", "mbtcp.unit_id",
FT_UINT8, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
};
+ static ei_register_info mbtcp_ei[] = {
+ { &ei_mbtcp_cannot_classify,
+ { "mbtcp.cannot_classify", PI_PROTOCOL, PI_WARN,
+ "Cannot classify packet type. Try setting Modbus/TCP Port preference to this destination or source port", EXPFILL }
+ },
+ };
+
+ /* Modbus RTU header fields */
static hf_register_info mbrtu_hf[] = {
{ &hf_mbrtu_unitid,
- { "Unit ID", "mbrtu.unit_id",
+ { "Unit ID", "mbrtu.unit_id",
FT_UINT8, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_mbrtu_crc16,
- { "CRC-16", "mbrtu.crc16",
+ { "CRC-16", "mbrtu.crc16",
FT_UINT16, BASE_HEX, NULL, 0x0,
NULL, HFILL }
},
+ { &hf_mbrtu_crc16_status,
+ { "CRC-16 Status", "mbrtu.crc16.status",
+ FT_UINT8, BASE_NONE, VALS(proto_checksum_vals), 0x0,
+ NULL, HFILL }
+ },
};
static ei_register_info mbrtu_ei[] = {
- { &ei_mbrtu_crc16_incorrect, { "mbrtu.crc16.incorrect", PI_CHECKSUM, PI_WARN, "Incorrect CRC", EXPFILL }},
+ { &ei_mbrtu_crc16_incorrect,
+ { "mbrtu.crc16.incorrect", PI_CHECKSUM, PI_WARN,
+ "Incorrect CRC", EXPFILL }
+ },
};
+ /* Modbus header fields */
static hf_register_info hf[] = {
- /* Modbus header fields */
- { &hf_mbtcp_functioncode,
- { "Function Code", "modbus.func_code",
- FT_UINT8, BASE_DEC, VALS(function_code_vals), 0x0,
+ { &hf_modbus_request_frame,
+ { "Request Frame", "modbus.request_frame",
+ FT_FRAMENUM, BASE_NONE,
+ NULL, 0x0,
+ NULL, HFILL }
+ },
+ { &hf_modbus_functioncode,
+ { "Function Code", "modbus.func_code",
+ FT_UINT8, BASE_DEC, VALS(function_code_vals), 0x7F,
NULL, HFILL }
},
{ &hf_modbus_reference,
- { "Reference Number", "modbus.reference_num",
+ { "Reference Number", "modbus.reference_num",
FT_UINT16, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
+ { &hf_modbus_padding,
+ { "Padding", "modbus.padding",
+ FT_UINT8, BASE_HEX, NULL, 0x0,
+ NULL, HFILL }
+ },
{ &hf_modbus_lreference,
- { "Reference Number (32 bit)", "modbus.reference_num_32",
+ { "Reference Number (32 bit)", "modbus.reference_num_32",
FT_UINT32, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_modbus_reftype,
- { "Reference Type", "modbus.reference_type",
+ { "Reference Type", "modbus.reference_type",
FT_UINT8, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_modbus_readref,
- { "Read Reference Number", "modbus.read_reference_num",
+ { "Read Reference Number", "modbus.read_reference_num",
FT_UINT16, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_modbus_writeref,
- { "Write Reference Number", "modbus.write_reference_num",
+ { "Write Reference Number", "modbus.write_reference_num",
FT_UINT16, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_modbus_wordcnt,
- { "Word Count", "modbus.word_cnt",
+ { "Word Count", "modbus.word_cnt",
FT_UINT16, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_modbus_readwordcnt,
- { "Read Word Count", "modbus.read_word_cnt",
+ { "Read Word Count", "modbus.read_word_cnt",
FT_UINT16, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_modbus_writewordcnt,
- { "Write Word Count", "modbus.write_word_cnt",
+ { "Write Word Count", "modbus.write_word_cnt",
FT_UINT16, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_modbus_bitcnt,
- { "Bit Count", "modbus.bit_cnt",
+ { "Bit Count", "modbus.bit_cnt",
FT_UINT16, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_modbus_bytecnt,
- { "Byte Count", "modbus.byte_cnt",
+ { "Byte Count", "modbus.byte_cnt",
FT_UINT8, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_modbus_lbytecnt,
- { "Byte Count (16-bit)", "modbus.byte_cnt_16",
+ { "Byte Count (16-bit)", "modbus.byte_cnt_16",
FT_UINT8, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_modbus_exceptioncode,
- { "Exception Code", "modbus.exception_code",
+ { "Exception Code", "modbus.exception_code",
FT_UINT8, BASE_DEC, VALS(exception_code_vals), 0x0,
NULL, HFILL }
},
{ &hf_modbus_diag_sf,
- { "Diagnostic Code", "modbus.diagnostic_code",
+ { "Diagnostic Code", "modbus.diagnostic_code",
FT_UINT16, BASE_DEC, VALS(diagnostic_code_vals), 0x0,
NULL, HFILL }
},
{ &hf_modbus_diag_return_query_data_request,
- { "Request Data", "modbus.diagnostic.return_query_data.request",
+ { "Request Data", "modbus.diagnostic.return_query_data.request",
FT_BYTES, BASE_NONE, NULL, 0x0,
NULL, HFILL }
},
{ &hf_modbus_diag_return_query_data_echo,
- { "Echo Data", "modbus.diagnostic.return_query_data.echo",
+ { "Echo Data", "modbus.diagnostic.return_query_data.echo",
FT_BYTES, BASE_NONE, NULL, 0x0,
NULL, HFILL }
},
FT_UINT8, BASE_HEX, NULL, 0x0,
NULL, HFILL }
},
+ { &hf_modbus_diag_clear_ctr_diag_reg,
+ { "Clear Counters & Diag Register Echo", "modbus.diagnostic.clear_ctr_diag_reg",
+ FT_UINT16, BASE_DEC, NULL, 0x0,
+ NULL, HFILL }
+ },
{ &hf_modbus_diag_return_bus_message_count,
{ "Total Message Count", "modbus.diagnostic.bus_message_count",
FT_UINT16, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_modbus_status,
- { "Status", "modbus.ev_status",
+ { "Status", "modbus.ev_status",
FT_UINT16, BASE_HEX, NULL, 0x0,
NULL, HFILL }
},
+ { &hf_modbus_event,
+ { "Event", "modbus.event",
+ FT_UINT8, BASE_DEC, NULL, 0x0,
+ NULL, HFILL }
+ },
{ &hf_modbus_event_count,
- { "Event Vount", "modbus.ev_count",
+ { "Event Count", "modbus.ev_count",
FT_UINT16, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_modbus_message_count,
- { "Message Count", "modbus.ev_msg_count",
+ { "Message Count", "modbus.ev_msg_count",
FT_UINT16, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_modbus_event_recv_comm_err,
- { "Communication Error", "modbus.ev_recv_comm_err",
+ { "Communication Error", "modbus.ev_recv_comm_err",
FT_UINT8, BASE_DEC, NULL, 0x02,
NULL, HFILL }
},
{ &hf_modbus_event_recv_char_over,
- { "Character Overrun", "modbus.ev_recv_char_over",
+ { "Character Overrun", "modbus.ev_recv_char_over",
FT_UINT8, BASE_DEC, NULL, 0x10,
NULL, HFILL }
},
NULL, HFILL }
},
{ &hf_modbus_event_recv_broadcast,
- { "Broadcast Received", "modbus.ev_recv_broadcast",
+ { "Broadcast Received", "modbus.ev_recv_broadcast",
FT_UINT8, BASE_DEC, NULL, 0x40,
NULL, HFILL }
},
{ &hf_modbus_event_send_read_ex,
- { "Read Exception Sent", "modbus.ev_send_read_ex",
+ { "Read Exception Sent", "modbus.ev_send_read_ex",
FT_UINT8, BASE_DEC, NULL, 0x01,
NULL, HFILL }
},
{ &hf_modbus_event_send_slave_abort_ex,
- { "Slave Abort Exception Sent", "modbus.ev_send_slave_abort_ex",
+ { "Slave Abort Exception Sent", "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", "modbus.ev_send_slave_busy_ex",
+ { "Slave Busy Exception Sent", "modbus.ev_send_slave_busy_ex",
FT_UINT8, BASE_DEC, NULL, 0x04,
NULL, HFILL }
},
NULL, HFILL }
},
{ &hf_modbus_event_send_write_timeout,
- { "Write Timeout Error Occurred", "modbus.ev_send_write_timeout",
+ { "Write Timeout Error Occurred", "modbus.ev_send_write_timeout",
FT_UINT8, BASE_DEC, NULL, 0x10,
NULL, HFILL }
},
NULL, HFILL }
},
{ &hf_modbus_andmask,
- { "AND mask", "modbus.and_mask",
+ { "AND mask", "modbus.and_mask",
FT_UINT16, BASE_HEX, NULL, 0x0,
NULL, HFILL }
},
{ &hf_modbus_ormask,
- { "OR mask", "modbus.or_mask",
+ { "OR mask", "modbus.or_mask",
FT_UINT16, BASE_HEX, NULL, 0x0,
NULL, HFILL }
},
{ &hf_modbus_data,
- { "Data", "modbus.data",
+ { "Data", "modbus.data",
FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL }
},
{ &hf_modbus_mei,
- { "MEI type", "modbus.mei",
+ { "MEI type", "modbus.mei",
FT_UINT8, BASE_DEC, VALS(encap_interface_code_vals), 0x0,
NULL, HFILL }
},
{ &hf_modbus_read_device_id,
- { "Read Device ID", "modbus.read_device_id",
+ { "Read Device ID", "modbus.read_device_id",
FT_UINT8, BASE_DEC, VALS(read_device_id_vals), 0x0,
NULL, HFILL }
},
{ &hf_modbus_object_id,
- { "Object ID", "modbus.object_id",
+ { "Object ID", "modbus.object_id",
FT_UINT8, BASE_DEC, VALS(object_id_vals), 0x0,
NULL, HFILL }
},
{ &hf_modbus_num_objects,
- { "Number of Objects", "modbus.num_objects",
+ { "Number of Objects", "modbus.num_objects",
FT_UINT8, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_modbus_list_object_len,
- { "Object length", "modbus.objects_len",
+ { "Object length", "modbus.objects_len",
FT_UINT8, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_modbus_conformity_level,
- { "Conformity Level", "modbus.conformity_level",
+ { "Conformity Level", "modbus.conformity_level",
FT_UINT8, BASE_HEX, VALS(conformity_level_vals), 0x0,
NULL, HFILL }
},
{ &hf_modbus_more_follows,
- { "More Follows", "modbus.more_follows",
+ { "More Follows", "modbus.more_follows",
FT_UINT8, BASE_HEX, NULL, 0x0,
NULL, HFILL }
},
{ &hf_modbus_next_object_id,
- { "Next Object ID", "modbus.next_object_id",
+ { "Next Object ID", "modbus.next_object_id",
FT_UINT8, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
{ &hf_modbus_object_str_value,
- { "Object String Value", "modbus.object_str_value",
+ { "Object String Value", "modbus.object_str_value",
FT_STRING, BASE_NONE, NULL, 0x0,
NULL, HFILL }
},
- { &hf_modbus_reg_uint16,
- { "Register (UINT16)", "modbus.register.uint16",
- FT_UINT16, BASE_DEC, NULL, 0x0,
- NULL, HFILL }
- },
- { &hf_modbus_reg_uint32,
- { "Register (UINT32)", "modbus.register.uint32",
- FT_UINT32, BASE_DEC, NULL, 0x0,
+ { &hf_modbus_object_value,
+ { "Object Value", "modbus.object_value",
+ FT_BYTES, BASE_NONE, NULL, 0x0,
NULL, HFILL }
},
- { &hf_modbus_reg_ieee_float,
- { "Register (IEEE Float)", "modbus.register.ieee_float",
- FT_FLOAT, BASE_NONE, NULL, 0x0,
+ { &hf_modbus_reg16,
+ { "Register Value (16-bit)", "modbus.reg16",
+ FT_UINT16, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
- { &hf_modbus_reg_modicon_float,
- { "Register (Modicon Float)", "modbus.register.modicon_float",
- FT_FLOAT, BASE_NONE, NULL, 0x0,
+ { &hf_modbus_reg32,
+ { "Register Value (32-bit)", "modbus.reg32",
+ FT_UINT32, BASE_DEC, NULL, 0x0,
NULL, HFILL }
},
};
};
static ei_register_info ei[] = {
- { &ei_modbus_data_decode, { "modbus.data.decode", PI_PROTOCOL, PI_WARN, "Invalid decoding options, register data not a multiple of 4!", EXPFILL }},
+ { &ei_modbus_data_decode,
+ { "modbus.data.decode", PI_PROTOCOL, PI_WARN,
+ "Invalid decoding options, register data not a multiple of 4!", EXPFILL }
+ },
};
-
module_t *mbtcp_module;
module_t *mbrtu_module;
+ module_t *modbus_module;
+ expert_module_t* expert_mbtcp;
expert_module_t* expert_mbrtu;
expert_module_t* expert_modbus;
/* Register the protocol name and description */
proto_mbtcp = proto_register_protocol("Modbus/TCP", "Modbus/TCP", "mbtcp");
+ proto_mbudp = proto_register_protocol("Modbus/UDP", "Modbus/UDP", "mbudp");
proto_mbrtu = proto_register_protocol("Modbus RTU", "Modbus RTU", "mbrtu");
proto_modbus = proto_register_protocol("Modbus", "Modbus", "modbus");
/* Registering protocol to be called by another dissector */
- modbus_handle = new_register_dissector("modbus", dissect_modbus, proto_modbus);
- mbtcp_handle = new_register_dissector("mbtcp", dissect_mbtcp, proto_mbtcp);
- mbrtu_handle = new_register_dissector("mbrtu", dissect_mbrtu, proto_mbrtu);
+ modbus_handle = register_dissector("modbus", dissect_modbus, proto_modbus);
+ mbtcp_handle = register_dissector("mbtcp", dissect_mbtcp, proto_mbtcp);
+ mbrtu_handle = register_dissector("mbrtu", dissect_mbrtu, proto_mbrtu);
+ mbudp_handle = register_dissector("mbudp", dissect_mbudp, proto_mbudp);
/* Registering subdissectors table */
- modbus_data_dissector_table = register_dissector_table("modbus.data", "Modbus Data", FT_STRING, BASE_NONE);
- modbus_dissector_table = register_dissector_table("mbtcp.prot_id", "Modbus/TCP protocol identifier", FT_UINT16, BASE_DEC);
+ modbus_data_dissector_table = register_dissector_table("modbus.data", "Modbus Data", proto_modbus, FT_STRING, BASE_NONE);
+ modbus_dissector_table = register_dissector_table("mbtcp.prot_id", "Modbus/TCP protocol identifier", proto_mbtcp, FT_UINT16, BASE_DEC);
/* Required function calls to register the header fields and subtrees used */
proto_register_field_array(proto_mbtcp, mbtcp_hf, array_length(mbtcp_hf));
proto_register_field_array(proto_mbrtu, mbrtu_hf, array_length(mbrtu_hf));
proto_register_field_array(proto_modbus, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
+ expert_mbtcp = expert_register_protocol(proto_mbtcp);
+ expert_register_field_array(expert_mbtcp, mbtcp_ei, array_length(mbtcp_ei));
expert_mbrtu = expert_register_protocol(proto_mbrtu);
expert_register_field_array(expert_mbrtu, mbrtu_ei, array_length(mbrtu_ei));
expert_modbus = expert_register_protocol(proto_modbus);
expert_register_field_array(expert_modbus, ei, array_length(ei));
- /* Register required preferences for Modbus Protocol register decoding */
- mbtcp_module = prefs_register_protocol(proto_mbtcp, proto_reg_handoff_mbtcp);
- mbrtu_module = prefs_register_protocol(proto_mbrtu, proto_reg_handoff_mbrtu);
+ /* Register required preferences for Modbus Protocol variants */
+ mbtcp_module = prefs_register_protocol(proto_mbtcp, apply_mbtcp_prefs);
+ mbrtu_module = prefs_register_protocol(proto_mbrtu, apply_mbrtu_prefs);
+ modbus_module = prefs_register_protocol(proto_modbus, NULL);
/* Modbus RTU Preference - Desegment, defaults to TRUE for TCP desegmentation */
prefs_register_bool_preference(mbtcp_module, "desegment",
"Whether the Modbus RTU dissector should desegment all messages spanning multiple TCP segments",
&mbtcp_desegment);
- /* Modbus/TCP Preference - Default TCP Port, allows for "user" port either than 502. */
- prefs_register_uint_preference(mbtcp_module, "tcp.port", "Modbus/TCP Port",
- "Set the TCP port for Modbus/TCP packets (if other"
- " than the default of 502)",
- 10, &global_mbus_tcp_port);
-
- /* Modbus/TCP Preference - Holding/Input Register format, this allows for deeper dissection of response data */
- prefs_register_enum_preference(mbtcp_module, "mbus_register_format",
- "Holding/Input Register Format",
- "Register Format",
- &global_mbus_tcp_register_format,
- mbus_register_format,
- TRUE);
-
- /* Modbus/TCP Preference - Register addressing format, this allows for a configurable display option to determine addressing used */
- prefs_register_enum_preference(mbtcp_module, "mbus_register_addr_type",
- "Register Addressing Type",
- "Register Addressing Type (Raw, Modicon 5 or 6). This option has no effect on the underlying protocol, but changes the register address display format",
- &global_mbus_tcp_register_addr_type,
- mbus_register_addr_type,
- TRUE);
-
/* Modbus RTU Preference - Desegment, defaults to TRUE for TCP desegmentation */
prefs_register_bool_preference(mbrtu_module, "desegment",
"Desegment all Modbus RTU packets spanning multiple TCP segments",
"Whether the Modbus RTU dissector should desegment all messages spanning multiple TCP segments",
&mbrtu_desegment);
- /* Modbus RTU Preference - CRC verification, defaults to FALSE (not do verification)*/
+ /* Modbus RTU Preference - CRC verification, defaults to FALSE (no verification)*/
prefs_register_bool_preference(mbrtu_module, "crc_verification",
"Validate CRC",
"Whether to validate the CRC",
&mbrtu_crc);
- /* Modbus RTU Preference - Default TCP Port, defaults to zero, allows custom user port. */
- prefs_register_uint_preference(mbrtu_module, "tcp.port", "Modbus RTU Port",
- "Set the TCP port for encapsulated Modbus RTU packets",
- 10, &global_mbus_rtu_port);
-
- /* Modbus RTU Preference - Holding/Input Register format, this allows for deeper dissection of response data */
- prefs_register_enum_preference(mbrtu_module, "mbus_register_format",
+ /* Modbus Preference - Holding/Input Register format, this allows for deeper dissection of response data */
+ prefs_register_enum_preference(modbus_module, "mbus_register_format",
"Holding/Input Register Format",
"Register Format",
- &global_mbus_rtu_register_format,
+ &global_mbus_register_format,
mbus_register_format,
- TRUE);
+ FALSE);
- /* Modbus RTU Preference - Register addressing format, this allows for a configurable display option to determine addressing used */
- prefs_register_enum_preference(mbrtu_module, "mbus_register_addr_type",
- "Register Addressing Type",
- "Register Addressing Type (Raw, Modicon 5 or 6). This option has no effect on the underlying protocol, but changes the register address display format",
- &global_mbus_rtu_register_addr_type,
- mbus_register_addr_type,
- TRUE);
+ /* Obsolete Preferences */
+ prefs_register_obsolete_preference(mbtcp_module, "mbus_register_addr_type");
+ prefs_register_obsolete_preference(mbtcp_module, "mbus_register_format");
+ prefs_register_obsolete_preference(mbrtu_module, "mbus_register_addr_type");
+ prefs_register_obsolete_preference(mbrtu_module, "mbus_register_format");
}
void
proto_reg_handoff_mbtcp(void)
{
- static unsigned int mbtcp_port;
-
- /* Make sure to use Modbus/TCP Preferences field to determine default TCP port */
-
- if(mbtcp_port != 0 && mbtcp_port != global_mbus_tcp_port){
- dissector_delete_uint("tcp.port", mbtcp_port, mbtcp_handle);
- }
-
- if(global_mbus_tcp_port != 0 && mbtcp_port != global_mbus_tcp_port) {
- dissector_add_uint("tcp.port", global_mbus_tcp_port, mbtcp_handle);
- }
-
- mbtcp_port = global_mbus_tcp_port;
+ dissector_add_uint_with_preference("tcp.port", PORT_MBTCP, mbtcp_handle);
+ dissector_add_uint_with_preference("udp.port", PORT_MBTCP, mbudp_handle);
dissector_add_uint("mbtcp.prot_id", MODBUS_PROTOCOL_ID, modbus_handle);
void
proto_reg_handoff_mbrtu(void)
{
- static unsigned int mbrtu_port = 0;
+ dissector_handle_t mbrtu_udp_handle = create_dissector_handle(dissect_mbrtu_udp, proto_mbrtu);
/* Make sure to use Modbus RTU Preferences field to determine default TCP port */
-
- if(mbrtu_port != 0 && mbrtu_port != global_mbus_rtu_port){
- dissector_delete_uint("tcp.port", mbrtu_port, mbrtu_handle);
- }
-
- if(global_mbus_rtu_port != 0 && mbrtu_port != global_mbus_rtu_port) {
- dissector_add_uint("tcp.port", global_mbus_rtu_port, mbrtu_handle);
- }
-
- mbrtu_port = global_mbus_rtu_port;
+ dissector_add_for_decode_as_with_preference("udp.port", mbrtu_udp_handle);
+ dissector_add_for_decode_as_with_preference("tcp.port", mbrtu_handle);
dissector_add_uint("mbtcp.prot_id", MODBUS_PROTOCOL_ID, modbus_handle);
+ dissector_add_for_decode_as("rtacser.data", mbrtu_handle);
+ dissector_add_for_decode_as("usb.device", mbrtu_handle);
+ dissector_add_for_decode_as("usb.product", mbrtu_handle);
+ dissector_add_for_decode_as("usb.protocol", mbrtu_handle);
}
+
+/*
+ * Editor modelines
+ *
+ * Local Variables:
+ * c-basic-offset: 4
+ * tab-width: 8
+ * indent-tabs-mode: nil
+ * End:
+ *
+ * ex: set shiftwidth=4 tabstop=8 expandtab:
+ * :indentSize=4:tabSize=8:noTabs=true:
+ */
git.samba.org / metze / wireshark / wip.git / blobdiff