epan/dissectors/packet-tdmop.c

   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 Relay 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 dissector_handle_t tdmop_handle;
  28
  29 static int proto_tdmop;
  30 static int ett_tdmop;
  31 static int ett_tdmop_channel;
  32
  33 static int hf_tdmop_TransferID;
  34 static int hf_tdmop_DstCh;
  35 static int hf_tdmop_SrcCh;
  36 static int hf_tdmop_Flags;
  37 static int hf_tdmop_Flags_no_data;
  38 static int hf_tdmop_Flags_lost_request;
  39 static int hf_tdmop_Flags_remote_no_data;
  40 static int hf_tdmop_Flags_compressed;
  41 static int hf_tdmop_SrcDst;
  42 static int hf_tdmop_SeqNum;
  43 static int hf_tdmop_LastRecv;
  44 static int hf_tdmop_Delay;
  45 static int hf_tdmop_Reserved;
  46 static int hf_tdmop_payload;
  47 static int hf_tdmop_Compression_mask;
  48
  49 static dissector_handle_t lapd_handle;
  50
  51 static int pref_tdmop_d_channel      = 16;
  52 static uint32_t pref_tdmop_mask        = 0xFFFFFFFFUL;
  53 static uint32_t pref_tdmop_ethertype   = ETHERTYPE_TDMOP;
  54
  55 #define TDMOP_FLAG_NO_DATA (1<<3)
  56 #define TDMOP_FLAG_REMOTE_NO_DATA (1<<2)
  57 #define TDMOP_FLAG_COMPRESSED (1<<4)
  58 #define TDMOP_FLAG_LOST_REQUEST ((1<<3)|(0x02))
  59
  60 static uint8_t reverse_map[256]=
  61 {
  62 0x00,0x80,0x40,0xC0,0x20,0xA0,0x60,0xE0,0x10,0x90,0x50,0xD0,0x30,0xB0,0x70,0xF0,
  63 0x08,0x88,0x48,0xC8,0x28,0xA8,0x68,0xE8,0x18,0x98,0x58,0xD8,0x38,0xB8,0x78,0xF8,
  64 0x04,0x84,0x44,0xC4,0x24,0xA4,0x64,0xE4,0x14,0x94,0x54,0xD4,0x34,0xB4,0x74,0xF4,
  65 0x0C,0x8C,0x4C,0xCC,0x2C,0xAC,0x6C,0xEC,0x1C,0x9C,0x5C,0xDC,0x3C,0xBC,0x7C,0xFC,
  66 0x02,0x82,0x42,0xC2,0x22,0xA2,0x62,0xE2,0x12,0x92,0x52,0xD2,0x32,0xB2,0x72,0xF2,
  67 0x0A,0x8A,0x4A,0xCA,0x2A,0xAA,0x6A,0xEA,0x1A,0x9A,0x5A,0xDA,0x3A,0xBA,0x7A,0xFA,
  68 0x06,0x86,0x46,0xC6,0x26,0xA6,0x66,0xE6,0x16,0x96,0x56,0xD6,0x36,0xB6,0x76,0xF6,
  69 0x0E,0x8E,0x4E,0xCE,0x2E,0xAE,0x6E,0xEE,0x1E,0x9E,0x5E,0xDE,0x3E,0xBE,0x7E,0xFE,
  70 0x01,0x81,0x41,0xC1,0x21,0xA1,0x61,0xE1,0x11,0x91,0x51,0xD1,0x31,0xB1,0x71,0xF1,
  71 0x09,0x89,0x49,0xC9,0x29,0xA9,0x69,0xE9,0x19,0x99,0x59,0xD9,0x39,0xB9,0x79,0xF9,
  72 0x05,0x85,0x45,0xC5,0x25,0xA5,0x65,0xE5,0x15,0x95,0x55,0xD5,0x35,0xB5,0x75,0xF5,
  73 0x0D,0x8D,0x4D,0xCD,0x2D,0xAD,0x6D,0xED,0x1D,0x9D,0x5D,0xDD,0x3D,0xBD,0x7D,0xFD,
  74 0x03,0x83,0x43,0xC3,0x23,0xA3,0x63,0xE3,0x13,0x93,0x53,0xD3,0x33,0xB3,0x73,0xF3,
  75 0x0B,0x8B,0x4B,0xCB,0x2B,0xAB,0x6B,0xEB,0x1B,0x9B,0x5B,0xDB,0x3B,0xBB,0x7B,0xFB,
  76 0x07,0x87,0x47,0xC7,0x27,0xA7,0x67,0xE7,0x17,0x97,0x57,0xD7,0x37,0xB7,0x77,0xF7,
  77 0x0F,0x8F,0x4F,0xCF,0x2F,0xAF,0x6F,0xEF,0x1F,0x9F,0x5F,0xDF,0x3F,0xBF,0x7F,0xFF
  78 };
  79
  80 static int dissect_tdmop(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
  81 {
  82     uint8_t   dchannel_data[MAX_DCHANNEL_LEN];
  83     unsigned dchannel_len;
  84     uint8_t   flags;
  85     int offset;
  86     proto_item    *ti;
  87     proto_tree    *tdmop_tree;
  88     uint32_t dstch, srcch;
  89     flags = tvb_get_uint8(tvb, 4);
  90     offset = 0;
  91     col_set_str(pinfo->cinfo, COL_PROTOCOL, "TDMoP");
  92     col_clear(pinfo->cinfo, COL_INFO);
  93     if (flags & TDMOP_FLAG_LOST_REQUEST)
  94     {
  95         col_set_str(pinfo->cinfo, COL_INFO, "Lost Request");
  96     }
  97
  98     ti = proto_tree_add_item(tree, proto_tdmop, tvb, 0, -1, ENC_NA);
  99     tdmop_tree = proto_item_add_subtree(ti, ett_tdmop);
 100     /*path info*/
 101     proto_tree_add_item(tdmop_tree, hf_tdmop_TransferID, tvb, offset, 4, ENC_LITTLE_ENDIAN);
 102     offset += 2;
 103     proto_tree_add_item_ret_uint(tdmop_tree, hf_tdmop_DstCh, tvb, offset, 1, ENC_LITTLE_ENDIAN, &dstch);
 104     offset += 1;
 105     proto_tree_add_item_ret_uint(tdmop_tree, hf_tdmop_SrcCh, tvb, offset, 1, ENC_LITTLE_ENDIAN, &srcch);
 106     offset += 1;
 107
 108     /*conversation*/
 109     conversation_set_conv_addr_port_endpoints(pinfo, &pinfo->src, &pinfo->dst, CONVERSATION_TDMOP, srcch, dstch);
 110
 111     /*flags*/
 112     proto_tree_add_item(tdmop_tree, hf_tdmop_Flags, tvb, offset, 1, ENC_NA);
 113     proto_tree_add_item(tdmop_tree, hf_tdmop_Flags_no_data, tvb, offset, 1, ENC_NA);
 114     proto_tree_add_item(tdmop_tree, hf_tdmop_Flags_lost_request, tvb, offset, 1, ENC_NA);
 115     proto_tree_add_item(tdmop_tree, hf_tdmop_Flags_remote_no_data, tvb, offset, 1, ENC_NA);
 116     proto_tree_add_item(tdmop_tree, hf_tdmop_Flags_compressed, tvb, offset, 1, ENC_NA);
 117     offset += 1;
 118     /*sequence and delay info*/
 119     proto_tree_add_item(tdmop_tree, hf_tdmop_SrcDst, tvb, offset, 1, ENC_LITTLE_ENDIAN);
 120     offset += 1;
 121     proto_tree_add_item(tdmop_tree, hf_tdmop_SeqNum, tvb, offset, 2, ENC_LITTLE_ENDIAN);
 122     offset += 2;
 123     proto_tree_add_item(tdmop_tree, hf_tdmop_LastRecv, tvb, offset, 2, ENC_LITTLE_ENDIAN);
 124     offset += 2;
 125     proto_tree_add_item(tdmop_tree, hf_tdmop_Delay, tvb, offset, 2, ENC_LITTLE_ENDIAN);
 126     offset += 2;
 127     proto_tree_add_item(tdmop_tree, hf_tdmop_Reserved, tvb, offset, 2, ENC_LITTLE_ENDIAN);
 128     offset += 2;
 129     if ((flags & TDMOP_FLAG_NO_DATA)==0)
 130     {
 131         int len;
 132         int blockid;
 133         dchannel_len=0;
 134         len=tvb_captured_length_remaining(tvb, 0);
 135         proto_tree_add_item(tdmop_tree, hf_tdmop_payload, tvb, offset, -1, ENC_NA);
 136         blockid=0;
 137         /*demux TDM stream*/
 138         while (offset<len)
 139         {
 140             proto_tree *currentblock = proto_tree_add_subtree_format(tdmop_tree, tvb, 0, 0, ett_tdmop_channel, 0, "Block %d", blockid);
 141             uint32_t mask;
 142             int i;
 143             int j;
 144             blockid++;
 145             mask = pref_tdmop_mask; /*default mask is for timeslots 1-32*/
 146             if (flags&TDMOP_FLAG_COMPRESSED)
 147             {
 148                 mask = tvb_get_letohl(tvb,offset);
 149                 mask = ((mask >> 16) & 0xFFFF)|((mask & 0xFFFF) << 16);
 150                 proto_tree_add_uint(currentblock, hf_tdmop_Compression_mask, tvb, offset, 4, mask);
 151                 offset+=4;
 152             }
 153             for (i=0; i<32; i++)
 154             {
 155                 if (mask & (1UL<<i))
 156                 {
 157                     proto_tree *subtree;
 158                     tvbuff_t *cdata;
 159                     subtree = proto_tree_add_subtree_format(currentblock, tvb, 0, 0, ett_tdmop_channel, 0, "Channel %d", i);
 160                     cdata = tvb_new_subset_length(tvb, offset, 4);
 161                     if (i==pref_tdmop_d_channel)
 162                     {
 163                         if (dchannel_len + 4 < MAX_DCHANNEL_LEN)
 164                         {
 165                             for (j = 0; j < 4; j++)
 166                             {
 167                                 dchannel_data[dchannel_len+j]=reverse_map[tvb_get_uint8(cdata, j)];
 168                             }
 169                             dchannel_len += 4;
 170                         }
 171                     } else
 172                     {
 173                         call_data_dissector(cdata, pinfo, subtree);
 174                     }
 175                     offset += 4;
 176                 }
 177             }
 178         }
 179         if (dchannel_len>0)
 180         {
 181             uint8_t *buff = (uint8_t *)wmem_memdup(pinfo->pool, dchannel_data, dchannel_len);
 182             tvbuff_t *new_tvb;
 183             new_tvb = tvb_new_child_real_data(tvb, buff, dchannel_len, dchannel_len);
 184             call_dissector(lapd_handle, new_tvb, pinfo, tree);
 185         }
 186     }
 187     return tvb_captured_length(tvb);
 188 }
 189
 190 void proto_register_tdmop(void)
 191 {
 192     module_t *tdmop_module;
 193     static hf_register_info hf[] =
 194     {
 195         {
 196             &hf_tdmop_TransferID,
 197             {    "TDMoP Transfer ID", "tdmop.transferid",
 198                 FT_UINT32, BASE_HEX,
 199                 NULL, 0x0,
 200                 NULL, HFILL}
 201         },
 202         {
 203             &hf_tdmop_DstCh,
 204             {    "TDMoP Dst Ch", "tdmop.dstch",
 205                 FT_UINT8, BASE_DEC,
 206                 NULL, 0x0,
 207                 NULL, HFILL}
 208         },
 209         {
 210             &hf_tdmop_SrcCh,
 211             {    "TDMoP Src Ch", "tdmop.srcch",
 212                 FT_UINT8, BASE_DEC,
 213                 NULL, 0x0,
 214                 NULL, HFILL}
 215         },
 216         {
 217             &hf_tdmop_Flags,
 218             {    "TDMoP Flags", "tdmop.flags",
 219                 FT_UINT8, BASE_DEC,
 220                 NULL, 0x0,
 221                 NULL, HFILL}
 222         },
 223         {
 224             &hf_tdmop_Flags_lost_request,
 225             {    "TDMoP Lost Request Flag", "tdmop.flags.lostrequest",
 226                 FT_BOOLEAN, 8,
 227                 NULL, TDMOP_FLAG_LOST_REQUEST,
 228                 NULL, HFILL}
 229         },
 230         {
 231             &hf_tdmop_Flags_no_data,
 232             {    "TDMoP No data flag", "tdmop.flags.nodata",
 233                 FT_BOOLEAN, 8,
 234                 NULL, TDMOP_FLAG_NO_DATA,
 235                 NULL, HFILL}
 236         },
 237         {
 238             &hf_tdmop_Flags_remote_no_data,
 239             {    "TDMoP No data received from remote side flag", "tdmop.flags.remotenodata",
 240                 FT_BOOLEAN, 8,
 241                 NULL, TDMOP_FLAG_REMOTE_NO_DATA,
 242                 NULL, HFILL}
 243         },
 244         {
 245             &hf_tdmop_Flags_compressed,
 246             {    "TDMoP compressed framed", "tdmop.flags.compressed",
 247                 FT_BOOLEAN, 8,
 248                 NULL, TDMOP_FLAG_COMPRESSED,
 249                 NULL, HFILL}
 250         },
 251         {
 252             &hf_tdmop_SrcDst,
 253             {    "TDMoP Short SrcDst", "tdmop.srcdst",
 254                 FT_UINT8, BASE_HEX,
 255                 NULL, 0x0,
 256                 NULL, HFILL}
 257         },
 258         {
 259             &hf_tdmop_SeqNum,
 260             {    "TDMoP Sequence number", "tdmop.seqnum",
 261                 FT_UINT16, BASE_DEC,
 262                 NULL, 0x0,
 263                 NULL, HFILL}
 264         },
 265         {
 266             &hf_tdmop_LastRecv,
 267             {    "TDMoP Last Received number", "tdmop.recvnumber",
 268                 FT_UINT16, BASE_DEC,
 269                 NULL, 0x0,
 270                 NULL, HFILL}
 271         },
 272         {
 273             &hf_tdmop_Delay,
 274             {    "TDMoP Delay", "tdmop.delay",
 275                 FT_UINT16, BASE_DEC,
 276                 NULL, 0x0,
 277                 NULL, HFILL}
 278         },
 279         {
 280             &hf_tdmop_Reserved,
 281             {    "TDMoP Reserved", "tdmop.reserved",
 282                 FT_UINT16, BASE_DEC,
 283                 NULL, 0x0,
 284                 NULL, HFILL}
 285         },
 286         {
 287             &hf_tdmop_payload,
 288             {    "TDMoP Payload", "tdmop.payload",
 289                 FT_BYTES, BASE_NONE,
 290                 NULL, 0x0,
 291                 NULL, HFILL}
 292         },
 293         {
 294             &hf_tdmop_Compression_mask,
 295             {    "TDMoP Compression mask", "tdmop.cmask",
 296                 FT_UINT32, BASE_HEX,
 297                 NULL, 0x0,
 298                 NULL, HFILL}
 299         }
 300     };
 301     static int *ett[] = {
 302         &ett_tdmop,
 303         &ett_tdmop_channel
 304     };
 305     proto_tdmop = proto_register_protocol ("TDMoP protocol", "TDMoP", "tdmop");
 306     proto_register_field_array(proto_tdmop, hf, array_length(hf));
 307     proto_register_subtree_array(ett, array_length(ett));
 308     tdmop_handle = register_dissector("tdmop", dissect_tdmop, proto_tdmop);
 309     tdmop_module = prefs_register_protocol(proto_tdmop, proto_reg_handoff_tdmop);
 310     prefs_register_uint_preference(tdmop_module, "d_channel",
 311                     "TDMoP D-Channel",
 312                     "The TDMoD channel that contains the D-Channel.",
 313                     10, &pref_tdmop_d_channel);
 314     prefs_register_uint_preference(tdmop_module, "ts_mask",
 315                     "TDMoP default timeslot mask",
 316                     "The bitmask of channels in uncompressed TDMoP frame",
 317                     16, &pref_tdmop_mask);
 318     prefs_register_uint_preference(tdmop_module, "ethertype",
 319                     "Ethertype for TDMoP stream(Usually 0808)",
 320                     "The ethertype assigned to TDMoP (without IP/UDP) stream",
 321                     16, &pref_tdmop_ethertype);
 322 }
 323
 324 void proto_reg_handoff_tdmop(void)
 325 {
 326     static bool init = false;
 327     static uint32_t current_tdmop_ethertype;
 328     if (!init)
 329     {
 330         dissector_add_for_decode_as_with_preference("udp.port", tdmop_handle);
 331
 332         if (pref_tdmop_ethertype) {
 333             dissector_add_uint("ethertype", pref_tdmop_ethertype, tdmop_handle);
 334         }
 335         lapd_handle = find_dissector_add_dependency("lapd-bitstream", proto_tdmop);
 336         current_tdmop_ethertype = pref_tdmop_ethertype;
 337         init = true;
 338     }
 339     if (current_tdmop_ethertype != pref_tdmop_ethertype)
 340     {
 341         dissector_delete_uint("ethertype", current_tdmop_ethertype, tdmop_handle);
 342         if (pref_tdmop_ethertype) {
 343             dissector_add_uint("ethertype", pref_tdmop_ethertype, tdmop_handle);
 344         }
 345         current_tdmop_ethertype = pref_tdmop_ethertype;
 346     }
 347 }
 348
 349 /*
 350  * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 351  *
 352  * Local variables:
 353  * c-basic-offset: 4
 354  * tab-width: 8
 355  * indent-tabs-mode: nil
 356  * End:
 357  *
 358  * vi: set shiftwidth=4 tabstop=8 expandtab:
 359  * :indentSize=4:tabSize=8:noTabs=true:
 360  */