1 /* packet-tdmop.c
2 * Routines for TDM over Packet network disassembly
3 * Copyright 2015, Andrew Chernyh <andew.chernyh@gmail.com>
4 *
5 * Wireshark - Network traffic analyzer
6 * By Gerald Combs <gerald@wireshark.org>
7 * Copyright 1998 Gerald Combs
8 *
9 * SPDX-License-Identifier: GPL-2.0-or-later
10 */
11 /*
12 * TDMoP protocol is proprietary protocol developed by "NSC Communication Siberia Ltd."
13 */
14 #include "config.h"
15 #include <epan/packet.h>
16 #include <epan/conversation.h>
17 #include <epan/prefs.h>
18
19 /*Using of ethertype 0x0808(assigned to Frame Realy ARP) was implemented in hardware, when ethertype was not assigned*/
20 #define ETHERTYPE_TDMOP 0
21
22 #define MAX_DCHANNEL_LEN 128
23
24 void proto_register_tdmop(void);
25 void proto_reg_handoff_tdmop(void);
26
27 static int proto_tdmop = -1;
28 static gint ett_tdmop = -1;
29 static gint ett_tdmop_channel = -1;
30
31 static int hf_tdmop_TransferID = -1;
32 static int hf_tdmop_DstCh = -1;
33 static int hf_tdmop_SrcCh = -1;
34 static int hf_tdmop_Flags = -1;
35 static int hf_tdmop_Flags_no_data = -1;
36 static int hf_tdmop_Flags_lost_request = -1;
37 static int hf_tdmop_Flags_remote_no_data = -1;
38 static int hf_tdmop_Flags_compressed = -1;
39 static int hd_tdmop_SrcDst = -1;
40 static int hd_tdmop_SeqNum = -1;
41 static int hd_tdmop_LastRecv = -1;
42 static int hd_tdmop_Delay = -1;
43 static int hd_tdmop_Reserved = -1;
44 static int hf_tdmop_payload = -1;
45 static int hf_tdmop_Compression_mask = -1;
46
47 static dissector_handle_t lapd_handle = NULL;
48
49 static gint pref_tdmop_d_channel = 16;
50 static guint32 pref_tdmop_mask = 0xFFFFFFFFUL;
51 static guint32 pref_tdmop_ethertype = ETHERTYPE_TDMOP;
52
53 #define TDMOP_FLAG_NO_DATA (1<<3)
54 #define TDMOP_FLAG_REMOTE_NO_DATA (1<<2)
55 #define TDMOP_FLAG_COMPRESSED (1<<4)
56 #define TDMOP_FLAG_LOST_REQUEST ((1<<3)|(0x02))
57
58 static guint8 reverse_map[256]=
59 {
60 0x00,0x80,0x40,0xC0,0x20,0xA0,0x60,0xE0,0x10,0x90,0x50,0xD0,0x30,0xB0,0x70,0xF0,
61 0x08,0x88,0x48,0xC8,0x28,0xA8,0x68,0xE8,0x18,0x98,0x58,0xD8,0x38,0xB8,0x78,0xF8,
62 0x04,0x84,0x44,0xC4,0x24,0xA4,0x64,0xE4,0x14,0x94,0x54,0xD4,0x34,0xB4,0x74,0xF4,
63 0x0C,0x8C,0x4C,0xCC,0x2C,0xAC,0x6C,0xEC,0x1C,0x9C,0x5C,0xDC,0x3C,0xBC,0x7C,0xFC,
64 0x02,0x82,0x42,0xC2,0x22,0xA2,0x62,0xE2,0x12,0x92,0x52,0xD2,0x32,0xB2,0x72,0xF2,
65 0x0A,0x8A,0x4A,0xCA,0x2A,0xAA,0x6A,0xEA,0x1A,0x9A,0x5A,0xDA,0x3A,0xBA,0x7A,0xFA,
66 0x06,0x86,0x46,0xC6,0x26,0xA6,0x66,0xE6,0x16,0x96,0x56,0xD6,0x36,0xB6,0x76,0xF6,
67 0x0E,0x8E,0x4E,0xCE,0x2E,0xAE,0x6E,0xEE,0x1E,0x9E,0x5E,0xDE,0x3E,0xBE,0x7E,0xFE,
68 0x01,0x81,0x41,0xC1,0x21,0xA1,0x61,0xE1,0x11,0x91,0x51,0xD1,0x31,0xB1,0x71,0xF1,
69 0x09,0x89,0x49,0xC9,0x29,0xA9,0x69,0xE9,0x19,0x99,0x59,0xD9,0x39,0xB9,0x79,0xF9,
70 0x05,0x85,0x45,0xC5,0x25,0xA5,0x65,0xE5,0x15,0x95,0x55,0xD5,0x35,0xB5,0x75,0xF5,
71 0x0D,0x8D,0x4D,0xCD,0x2D,0xAD,0x6D,0xED,0x1D,0x9D,0x5D,0xDD,0x3D,0xBD,0x7D,0xFD,
72 0x03,0x83,0x43,0xC3,0x23,0xA3,0x63,0xE3,0x13,0x93,0x53,0xD3,0x33,0xB3,0x73,0xF3,
73 0x0B,0x8B,0x4B,0xCB,0x2B,0xAB,0x6B,0xEB,0x1B,0x9B,0x5B,0xDB,0x3B,0xBB,0x7B,0xFB,
74 0x07,0x87,0x47,0xC7,0x27,0xA7,0x67,0xE7,0x17,0x97,0x57,0xD7,0x37,0xB7,0x77,0xF7,
75 0x0F,0x8F,0x4F,0xCF,0x2F,0xAF,0x6F,0xEF,0x1F,0x9F,0x5F,0xDF,0x3F,0xBF,0x7F,0xFF
76 };
77
dissect_tdmop(tvbuff_t * tvb,packet_info * pinfo,proto_tree * tree,void * data _U_)78 static int dissect_tdmop(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
79 {
80 guint8 dchannel_data[MAX_DCHANNEL_LEN];
81 guint dchannel_len;
82 guint8 flags;
83 gint offset;
84 proto_item *ti;
85 proto_tree *tdmop_tree;
86 guint32 dstch, srcch;
87 flags = tvb_get_guint8(tvb, 4);
88 offset = 0;
89 col_set_str(pinfo->cinfo, COL_PROTOCOL, "TDMoP");
90 col_clear(pinfo->cinfo, COL_INFO);
91 if (flags & TDMOP_FLAG_LOST_REQUEST)
92 {
93 col_add_fstr(pinfo->cinfo, COL_INFO, "Lost Request");
94 }
95
96 ti = proto_tree_add_item(tree, proto_tdmop, tvb, 0, -1, ENC_NA);
97 tdmop_tree = proto_item_add_subtree(ti, ett_tdmop);
98 /*path info*/
99 proto_tree_add_item(tdmop_tree, hf_tdmop_TransferID, tvb, offset, 4, ENC_LITTLE_ENDIAN);
100 offset += 2;
101 proto_tree_add_item_ret_uint(tdmop_tree, hf_tdmop_DstCh, tvb, offset, 1, ENC_LITTLE_ENDIAN, &dstch);
102 offset += 1;
103 proto_tree_add_item_ret_uint(tdmop_tree, hf_tdmop_SrcCh, tvb, offset, 1, ENC_LITTLE_ENDIAN, &srcch);
104 offset += 1;
105
106 /*conversation*/
107 conversation_create_endpoint(pinfo, &pinfo->src, &pinfo->dst, ENDPOINT_TDMOP, srcch, dstch, 0);
108
109 /*flags*/
110 proto_tree_add_item(tdmop_tree, hf_tdmop_Flags, tvb, offset, 1, ENC_NA);
111 proto_tree_add_item(tdmop_tree, hf_tdmop_Flags_no_data, tvb, offset, 1, ENC_NA);
112 proto_tree_add_item(tdmop_tree, hf_tdmop_Flags_lost_request, tvb, offset, 1, ENC_NA);
113 proto_tree_add_item(tdmop_tree, hf_tdmop_Flags_remote_no_data, tvb, offset, 1, ENC_NA);
114 proto_tree_add_item(tdmop_tree, hf_tdmop_Flags_compressed, tvb, offset, 1, ENC_NA);
115 offset += 1;
116 /*sequence and delay info*/
117 proto_tree_add_item(tdmop_tree, hd_tdmop_SrcDst, tvb, offset, 1, ENC_LITTLE_ENDIAN);
118 offset += 1;
119 proto_tree_add_item(tdmop_tree, hd_tdmop_SeqNum, tvb, offset, 2, ENC_LITTLE_ENDIAN);
120 offset += 2;
121 proto_tree_add_item(tdmop_tree, hd_tdmop_LastRecv, tvb, offset, 2, ENC_LITTLE_ENDIAN);
122 offset += 2;
123 proto_tree_add_item(tdmop_tree, hd_tdmop_Delay, tvb, offset, 2, ENC_LITTLE_ENDIAN);
124 offset += 2;
125 proto_tree_add_item(tdmop_tree, hd_tdmop_Reserved, tvb, offset, 2, ENC_LITTLE_ENDIAN);
126 offset += 2;
127 if ((flags & TDMOP_FLAG_NO_DATA)==0)
128 {
129 gint len;
130 gint blockid;
131 dchannel_len=0;
132 len=tvb_captured_length_remaining(tvb, 0);
133 proto_tree_add_item(tdmop_tree, hf_tdmop_payload, tvb, offset, -1, ENC_NA);
134 blockid=0;
135 /*demux TDM stream*/
136 while (offset<len)
137 {
138 proto_tree *currentblock = proto_tree_add_subtree_format(tdmop_tree, tvb, 0, 0, ett_tdmop_channel, 0, "Block %d", blockid);
139 guint32 mask;
140 gint i;
141 gint j;
142 blockid++;
143 mask = pref_tdmop_mask; /*default mask is for timeslots 1-32*/
144 if (flags&TDMOP_FLAG_COMPRESSED)
145 {
146 mask = tvb_get_letohl(tvb,offset);
147 mask = ((mask >> 16) & 0xFFFF)|((mask & 0xFFFF) << 16);
148 proto_tree_add_uint(currentblock, hf_tdmop_Compression_mask, tvb, offset, 4, mask);
149 offset+=4;
150 }
151 for (i=0; i<32; i++)
152 {
153 if (mask & (1UL<<i))
154 {
155 proto_tree *subtree;
156 tvbuff_t *cdata;
157 subtree = proto_tree_add_subtree_format(currentblock, tvb, 0, 0, ett_tdmop_channel, 0, "Channel %d", i);
158 cdata = tvb_new_subset_length(tvb, offset, 4);
159 if (i==pref_tdmop_d_channel)
160 {
161 if (dchannel_len + 4 < MAX_DCHANNEL_LEN)
162 {
163 for (j = 0; j < 4; j++)
164 {
165 dchannel_data[dchannel_len+j]=reverse_map[tvb_get_guint8(cdata, j)];
166 }
167 dchannel_len += 4;
168 }
169 } else
170 {
171 call_data_dissector(cdata, pinfo, subtree);
172 }
173 offset += 4;
174 }
175 }
176 }
177 if (dchannel_len>0)
178 {
179 guint8 *buff = (guint8 *)wmem_memdup(pinfo->pool, dchannel_data, dchannel_len);
180 tvbuff_t *new_tvb;
181 new_tvb = tvb_new_child_real_data(tvb, buff, dchannel_len, dchannel_len);
182 call_dissector(lapd_handle, new_tvb, pinfo, tree);
183 }
184 }
185 return tvb_captured_length(tvb);
186 }
187
proto_register_tdmop(void)188 void proto_register_tdmop(void)
189 {
190 module_t *tdmop_module;
191 static hf_register_info hf[] =
192 {
193 {
194 &hf_tdmop_TransferID,
195 { "TDMoP Transfer ID", "tdmop.transferid",
196 FT_UINT32, BASE_HEX,
197 NULL, 0x0,
198 NULL, HFILL}
199 },
200 {
201 &hf_tdmop_DstCh,
202 { "TDMoP Dst Ch", "tdmop.dstch",
203 FT_UINT8, BASE_DEC,
204 NULL, 0x0,
205 NULL, HFILL}
206 },
207 {
208 &hf_tdmop_SrcCh,
209 { "TDMoP Src Ch", "tdmop.srcch",
210 FT_UINT8, BASE_DEC,
211 NULL, 0x0,
212 NULL, HFILL}
213 },
214 {
215 &hf_tdmop_Flags,
216 { "TDMoP Flags", "tdmop.flags",
217 FT_UINT8, BASE_DEC,
218 NULL, 0x0,
219 NULL, HFILL}
220 },
221 {
222 &hf_tdmop_Flags_lost_request,
223 { "TDMoP Lost Request Flag", "tdmop.flags.lostrequest",
224 FT_BOOLEAN, 8,
225 NULL, TDMOP_FLAG_LOST_REQUEST,
226 NULL, HFILL}
227 },
228 {
229 &hf_tdmop_Flags_no_data,
230 { "TDMoP No data flag", "tdmop.flags.nodata",
231 FT_BOOLEAN, 8,
232 NULL, TDMOP_FLAG_NO_DATA,
233 NULL, HFILL}
234 },
235 {
236 &hf_tdmop_Flags_remote_no_data,
237 { "TDMoP No data received from remote side flag", "tdmop.flags.remotenodata",
238 FT_BOOLEAN, 8,
239 NULL, TDMOP_FLAG_REMOTE_NO_DATA,
240 NULL, HFILL}
241 },
242 {
243 &hf_tdmop_Flags_compressed,
244 { "TDMoP compressed framed", "tdmop.flags.compressed",
245 FT_BOOLEAN, 8,
246 NULL, TDMOP_FLAG_COMPRESSED,
247 NULL, HFILL}
248 },
249 {
250 &hd_tdmop_SrcDst,
251 { "TDMoP Short SrcDst", "tdmop.srcdst",
252 FT_UINT8, BASE_HEX,
253 NULL, 0x0,
254 NULL, HFILL}
255 },
256 {
257 &hd_tdmop_SeqNum,
258 { "TDMoP Sequence number", "tdmop.seqnum",
259 FT_UINT16, BASE_DEC,
260 NULL, 0x0,
261 NULL, HFILL}
262 },
263 {
264 &hd_tdmop_LastRecv,
265 { "TDMoP Last Received number", "tdmop.recvnumber",
266 FT_UINT16, BASE_DEC,
267 NULL, 0x0,
268 NULL, HFILL}
269 },
270 {
271 &hd_tdmop_Delay,
272 { "TDMoP Delay", "tdmop.delay",
273 FT_UINT16, BASE_DEC,
274 NULL, 0x0,
275 NULL, HFILL}
276 },
277 {
278 &hd_tdmop_Reserved,
279 { "TDMoP Reserved", "tdmop.reserved",
280 FT_UINT16, BASE_DEC,
281 NULL, 0x0,
282 NULL, HFILL}
283 },
284 {
285 &hf_tdmop_payload,
286 { "TDMoP Payload", "tdmop.payload",
287 FT_BYTES, BASE_NONE,
288 NULL, 0x0,
289 NULL, HFILL}
290 },
291 {
292 &hf_tdmop_Compression_mask,
293 { "TDMoP Compression mask", "tdmop.cmask",
294 FT_UINT32, BASE_HEX,
295 NULL, 0x0,
296 NULL, HFILL}
297 }
298 };
299 static gint *ett[] = {
300 &ett_tdmop,
301 &ett_tdmop_channel
302 };
303 proto_tdmop = proto_register_protocol ("TDMoP protocol", "TDMoP", "tdmop");
304 proto_register_field_array(proto_tdmop, hf, array_length(hf));
305 proto_register_subtree_array(ett, array_length(ett));
306 tdmop_module = prefs_register_protocol(proto_tdmop, proto_reg_handoff_tdmop);
307 prefs_register_uint_preference(tdmop_module, "d_channel",
308 "TDMoP D-Channel",
309 "The TDMoD channel that contains the D-Channel.",
310 10, &pref_tdmop_d_channel);
311 prefs_register_uint_preference(tdmop_module, "ts_mask",
312 "TDMoP default timeslot mask",
313 "The bitmask of channels in uncompressed TDMoP frame",
314 16, &pref_tdmop_mask);
315 prefs_register_uint_preference(tdmop_module, "ethertype",
316 "Ethertype for TDMoP stream(Usually 0808)",
317 "The ethertype assigned to TDMoP (without IP/UDP) stream",
318 16, &pref_tdmop_ethertype);
319 }
320
proto_reg_handoff_tdmop(void)321 void proto_reg_handoff_tdmop(void)
322 {
323 static dissector_handle_t tdmop_handle;
324 static gboolean init = FALSE;
325 static guint32 current_tdmop_ethertype;
326 if (!init)
327 {
328 tdmop_handle = create_dissector_handle(dissect_tdmop, proto_tdmop);
329 dissector_add_for_decode_as_with_preference("udp.port", tdmop_handle);
330
331 if (pref_tdmop_ethertype) {
332 dissector_add_uint("ethertype", pref_tdmop_ethertype, tdmop_handle);
333 }
334 lapd_handle = find_dissector_add_dependency("lapd-bitstream", proto_tdmop);
335 current_tdmop_ethertype = pref_tdmop_ethertype;
336 init = TRUE;
337 }
338 if (current_tdmop_ethertype != pref_tdmop_ethertype)
339 {
340 dissector_delete_uint("ethertype", current_tdmop_ethertype, tdmop_handle);
341 if (pref_tdmop_ethertype) {
342 dissector_add_uint("ethertype", pref_tdmop_ethertype, tdmop_handle);
343 }
344 current_tdmop_ethertype = pref_tdmop_ethertype;
345 }
346 }
347
348 /*
349 * Editor modelines - https://www.wireshark.org/tools/modelines.html
350 *
351 * Local variables:
352 * c-basic-offset: 4
353 * tab-width: 8
354 * indent-tabs-mode: nil
355 * End:
356 *
357 * vi: set shiftwidth=4 tabstop=8 expandtab:
358 * :indentSize=4:tabSize=8:noTabs=true:
359 */
360