2 * Routines for MTP2 dissection
3 * It is hopefully (needs testing) compliant to
6 * Copyright 2001, Michael Tuexen <tuexen [AT] fh-muenster.de>
8 * $Id: packet-mtp2.c,v 1.8 2003/04/22 13:47:38 tuexen Exp $
10 * Ethereal - Network traffic analyzer
11 * By Gerald Combs <gerald@ethereal.com>
12 * Copyright 1998 Gerald Combs
14 * Copied from packet-m2pa.c
16 * This program is free software; you can redistribute it and/or
17 * modify it under the terms of the GNU General Public License
18 * as published by the Free Software Foundation; either version 2
19 * of the License, or (at your option) any later version.
21 * This program is distributed in the hope that it will be useful,
22 * but WITHOUT ANY WARRANTY; without even the implied warranty of
23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
24 * GNU General Public License for more details.
26 * You should have received a copy of the GNU General Public License
27 * along with this program; if not, write to the Free Software
28 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
36 #include <epan/packet.h>
38 #define LITTLE_ENDIAN_BYTE_ORDER TRUE
40 /* Initialize the protocol and registered fields */
41 static int proto_mtp2 = -1;
42 static int hf_mtp2_bsn = -1;
43 static int hf_mtp2_bib = -1;
44 static int hf_mtp2_fsn = -1;
45 static int hf_mtp2_fib = -1;
46 static int hf_mtp2_li = -1;
47 static int hf_mtp2_spare = -1;
48 static int hf_mtp2_sf = -1;
49 static int hf_mtp2_long_sf = -1;
51 /* Initialize the subtree pointers */
52 static gint ett_mtp2 = -1;
54 static dissector_handle_t mtp3_handle;
55 static int mtp3_proto_id;
57 #define BSN_BIB_LENGTH 1
58 #define FSN_FIB_LENGTH 1
60 #define HEADER_LENGTH (BSN_BIB_LENGTH + FSN_FIB_LENGTH + LI_LENGTH)
62 #define BSN_BIB_OFFSET 0
63 #define FSN_FIB_OFFSET (BSN_BIB_OFFSET + BSN_BIB_LENGTH)
64 #define LI_OFFSET (FSN_FIB_OFFSET + FSN_FIB_LENGTH)
65 #define SIO_OFFSET (LI_OFFSET + LI_LENGTH)
72 #define SPARE_MASK 0xc0
75 dissect_mtp2_header(tvbuff_t *su_tvb, proto_item *mtp2_tree)
78 proto_tree_add_item(mtp2_tree, hf_mtp2_bsn, su_tvb, BSN_BIB_OFFSET, BSN_BIB_LENGTH, LITTLE_ENDIAN_BYTE_ORDER);
79 proto_tree_add_item(mtp2_tree, hf_mtp2_bib, su_tvb, BSN_BIB_OFFSET, BSN_BIB_LENGTH, LITTLE_ENDIAN_BYTE_ORDER);
80 proto_tree_add_item(mtp2_tree, hf_mtp2_fsn, su_tvb, FSN_FIB_OFFSET, FSN_FIB_LENGTH, LITTLE_ENDIAN_BYTE_ORDER);
81 proto_tree_add_item(mtp2_tree, hf_mtp2_fib, su_tvb, FSN_FIB_OFFSET, FSN_FIB_LENGTH, LITTLE_ENDIAN_BYTE_ORDER);
82 proto_tree_add_item(mtp2_tree, hf_mtp2_li, su_tvb, LI_OFFSET, LI_LENGTH, LITTLE_ENDIAN_BYTE_ORDER);
83 proto_tree_add_item(mtp2_tree, hf_mtp2_spare, su_tvb, LI_OFFSET, LI_LENGTH, LITTLE_ENDIAN_BYTE_ORDER);
88 dissect_mtp2_fisu(packet_info *pinfo)
90 if (check_col(pinfo->cinfo, COL_INFO))
91 col_set_str(pinfo->cinfo, COL_INFO, "FISU ");
94 static const value_string status_field_vals[] = {
95 { 0x0, "Status Indication O" },
96 { 0x1, "Status Indication N" },
97 { 0x2, "Status Indication E" },
98 { 0x3, "Status Indication OS" },
99 { 0x4, "Status Indication PO" },
100 { 0x5, "Status Indication BO" },
104 #define SF_OFFSET (LI_OFFSET + LI_LENGTH)
106 #define LONG_SF_LENGTH 2
109 dissect_mtp2_lssu(tvbuff_t *su_tvb, packet_info *pinfo, proto_item *mtp2_tree)
113 if (check_col(pinfo->cinfo, COL_INFO))
114 col_set_str(pinfo->cinfo, COL_INFO, "LSSU ");
117 li = tvb_get_guint8(su_tvb, LI_OFFSET);
118 if ((li & LI_MASK) == 1)
119 proto_tree_add_item(mtp2_tree, hf_mtp2_sf, su_tvb, SF_OFFSET, SF_LENGTH, LITTLE_ENDIAN_BYTE_ORDER);
121 proto_tree_add_item(mtp2_tree, hf_mtp2_long_sf, su_tvb, SF_OFFSET, LONG_SF_LENGTH, LITTLE_ENDIAN_BYTE_ORDER);
126 dissect_mtp2_msu(tvbuff_t *su_tvb, packet_info *pinfo, proto_item *mtp2_item, proto_item *tree)
129 tvbuff_t *sif_sio_tvb;
131 if (check_col(pinfo->cinfo, COL_INFO))
132 col_set_str(pinfo->cinfo, COL_INFO, "MSU ");
134 sif_sio_length = tvb_length(su_tvb) - HEADER_LENGTH;
135 sif_sio_tvb = tvb_new_subset(su_tvb, SIO_OFFSET, sif_sio_length, sif_sio_length);
136 call_dissector(mtp3_handle, sif_sio_tvb, pinfo, tree);
139 proto_item_set_len(mtp2_item, HEADER_LENGTH);
144 dissect_mtp2_su(tvbuff_t *su_tvb, packet_info *pinfo, proto_item *mtp2_item, proto_item *mtp2_tree, proto_tree *tree)
148 dissect_mtp2_header(su_tvb, mtp2_tree);
149 li = tvb_get_guint8(su_tvb, LI_OFFSET);
150 switch(li & LI_MASK) {
152 dissect_mtp2_fisu(pinfo);
156 dissect_mtp2_lssu(su_tvb, pinfo, mtp2_tree);
159 dissect_mtp2_msu(su_tvb, pinfo, mtp2_item, tree);
165 dissect_mtp2(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
167 proto_item *mtp2_item = NULL;
168 proto_tree *mtp2_tree = NULL;
170 if (check_col(pinfo->cinfo, COL_PROTOCOL))
171 col_set_str(pinfo->cinfo, COL_PROTOCOL, "MTP2");
174 mtp2_item = proto_tree_add_item(tree, proto_mtp2, tvb, 0, -1, FALSE);
175 mtp2_tree = proto_item_add_subtree(mtp2_item, ett_mtp2);
178 dissect_mtp2_su(tvb, pinfo, mtp2_item, mtp2_tree, tree);
182 proto_register_mtp2(void)
185 static hf_register_info hf[] = {
186 { &hf_mtp2_bsn, { "Backward sequence number", "mtp2.bsn", FT_UINT8, BASE_DEC, NULL, BSN_MASK, "", HFILL } },
187 { &hf_mtp2_bib, { "Backward indicator bit", "mtp2.bib", FT_UINT8, BASE_DEC, NULL, BIB_MASK, "", HFILL } },
188 { &hf_mtp2_fsn, { "Forward sequence number", "mtp2.fsn", FT_UINT8, BASE_DEC, NULL, FSN_MASK, "", HFILL } },
189 { &hf_mtp2_fib, { "Forward indicator bit", "mtp2.fib", FT_UINT8, BASE_DEC, NULL, FIB_MASK, "", HFILL } },
190 { &hf_mtp2_li, { "Length Indicator", "mtp2.li", FT_UINT8, BASE_DEC, NULL, LI_MASK, "", HFILL } },
191 { &hf_mtp2_spare, { "Spare", "mtp2.spare", FT_UINT8, BASE_DEC, NULL, SPARE_MASK, "", HFILL } },
192 { &hf_mtp2_sf, { "Status field", "mtp2.sf", FT_UINT8, BASE_DEC, VALS(status_field_vals), 0x0, "", HFILL } },
193 { &hf_mtp2_long_sf, { "Status field", "mtp2.sf", FT_UINT16, BASE_HEX, NULL, 0x0, "", HFILL } }
196 static gint *ett[] = {
200 proto_mtp2 = proto_register_protocol("Message Transfer Part Level 2", "MTP2", "mtp2");
201 register_dissector("mtp2", dissect_mtp2, proto_mtp2);
203 proto_register_field_array(proto_mtp2, hf, array_length(hf));
204 proto_register_subtree_array(ett, array_length(ett));
209 proto_reg_handoff_mtp2(void)
211 mtp3_handle = find_dissector("mtp3");
212 mtp3_proto_id = proto_get_id_by_filter_name("mtp3");