epan/dissectors/packet-btavctp.c

   1 /* packet-btavctp.c
   2  * Routines for Bluetooth AVCTP dissection
   3  *
   4  * Copyright 2012, Michal Labedzki for Tieto Corporation
   5  *
   6  * Wireshark - Network traffic analyzer
   7  * By Gerald Combs <gerald@wireshark.org>
   8  * Copyright 1998 Gerald Combs
   9  *
  10  * SPDX-License-Identifier: GPL-2.0-or-later
  11  */
  12
  13 #include "config.h"
  14
  15 #include <epan/packet.h>
  16 #include <epan/prefs.h>
  17 #include <epan/expert.h>
  18 #include <epan/decode_as.h>
  19 #include <epan/proto_data.h>
  20
  21 #include "packet-bluetooth.h"
  22 #include "packet-btl2cap.h"
  23 #include "packet-btsdp.h"
  24 #include "packet-btavctp.h"
  25
  26 #define PACKET_TYPE_SINGLE    0x00
  27 #define PACKET_TYPE_START     0x01
  28 #define PACKET_TYPE_CONTINUE  0x02
  29 #define PACKET_TYPE_END       0x03
  30
  31 int proto_btavctp;
  32
  33 static int hf_btavctp_transaction;
  34 static int hf_btavctp_packet_type;
  35 static int hf_btavctp_cr;
  36 static int hf_btavctp_ipid;
  37 static int hf_btavctp_rfa;
  38 static int hf_btavctp_pid;
  39 static int hf_btavctp_number_of_packets;
  40
  41 static int ett_btavctp;
  42
  43 static expert_field ei_btavctp_unexpected_frame;
  44 static expert_field ei_btavctp_invalid_profile;
  45
  46 static dissector_handle_t btavctp_handle;
  47
  48 typedef struct _fragment_t {
  49     unsigned   length;
  50     uint8_t *data;
  51 } fragment_t;
  52
  53 typedef struct _fragments_t {
  54     uint32_t     interface_id;
  55     uint32_t     adapter_id;
  56     uint32_t     chandle;
  57     uint32_t     psm;
  58     uint32_t     count;
  59     uint32_t     number_of_packets;
  60     uint32_t     pid;
  61     wmem_tree_t  *fragment;
  62 } fragments_t;
  63
  64 static wmem_tree_t *reassembling;
  65 static fragments_t *fragments;
  66
  67 static const value_string packet_type_vals[] = {
  68     { PACKET_TYPE_SINGLE,   "Single" },
  69     { PACKET_TYPE_START,    "Start" },
  70     { PACKET_TYPE_CONTINUE, "Continue" },
  71     { PACKET_TYPE_END,      "End" },
  72     { 0, NULL }
  73 };
  74
  75 static const value_string cr_vals[] = {
  76     { 0x00,   "Command" },
  77     { 0x01,   "Response" },
  78     { 0, NULL }
  79 };
  80
  81 static const value_string ipid_vals[] = {
  82     { 0x00,   "Profile OK" },
  83     { 0x01,   "Invalid profile" },
  84     { 0, NULL }
  85 };
  86
  87 void proto_register_btavctp(void);
  88 void proto_reg_handoff_btavctp(void);
  89
  90 static int
  91 dissect_btavctp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data)
  92 {
  93     proto_item      *ti;
  94     proto_tree      *btavctp_tree;
  95     proto_item      *pitem;
  96     proto_item      *ipid_item = NULL;
  97     btavctp_data_t  *avctp_data;
  98     tvbuff_t        *next_tvb;
  99     int             offset = 0;
 100     unsigned        packet_type;
 101     unsigned        cr;
 102     unsigned        pid = 0;
 103     unsigned        transaction;
 104     unsigned        number_of_packets = 0;
 105     unsigned        length;
 106     unsigned        i_frame;
 107     bool            ipid = false;
 108     uint32_t        interface_id;
 109     uint32_t        adapter_id;
 110     uint32_t        chandle;
 111     uint32_t        psm;
 112     int             previous_proto;
 113
 114     previous_proto = (GPOINTER_TO_INT(wmem_list_frame_data(wmem_list_frame_prev(wmem_list_tail(pinfo->layers)))));
 115     if (previous_proto == proto_btl2cap) {
 116         btl2cap_data_t  *l2cap_data;
 117
 118         l2cap_data = (btl2cap_data_t *) data;
 119
 120         interface_id = l2cap_data->interface_id;
 121         adapter_id   = l2cap_data->adapter_id;
 122         chandle      = l2cap_data->chandle;
 123         psm          = l2cap_data->psm;
 124     } else {
 125         interface_id = HCI_INTERFACE_DEFAULT;
 126         adapter_id   = HCI_ADAPTER_DEFAULT;
 127         chandle      = 0;
 128         psm          = 0;
 129     }
 130
 131     ti = proto_tree_add_item(tree, proto_btavctp, tvb, offset, tvb_captured_length_remaining(tvb, offset), ENC_NA);
 132     btavctp_tree = proto_item_add_subtree(ti, ett_btavctp);
 133
 134     col_set_str(pinfo->cinfo, COL_PROTOCOL, "AVCTP");
 135     col_clear(pinfo->cinfo, COL_INFO);
 136
 137     switch (pinfo->p2p_dir) {
 138         case P2P_DIR_SENT:
 139             col_set_str(pinfo->cinfo, COL_INFO, "Sent ");
 140             break;
 141         case P2P_DIR_RECV:
 142             col_set_str(pinfo->cinfo, COL_INFO, "Rcvd ");
 143             break;
 144         default:
 145             col_set_str(pinfo->cinfo, COL_INFO, "UnknownDirection ");
 146             break;
 147     }
 148
 149     proto_tree_add_item(btavctp_tree, hf_btavctp_transaction,  tvb, offset, 1, ENC_BIG_ENDIAN);
 150     pitem = proto_tree_add_item(btavctp_tree, hf_btavctp_packet_type,  tvb, offset, 1, ENC_BIG_ENDIAN);
 151     proto_tree_add_item(btavctp_tree, hf_btavctp_cr,  tvb, offset, 1, ENC_BIG_ENDIAN);
 152     transaction = tvb_get_uint8(tvb, offset) >> 4;
 153     packet_type = (tvb_get_uint8(tvb, offset) & 0x0C) >> 2;
 154     cr = (tvb_get_uint8(tvb, offset) & 0x02) >> 1 ;
 155
 156     if (packet_type == PACKET_TYPE_SINGLE || packet_type == PACKET_TYPE_START) {
 157         ipid_item = proto_tree_add_item(btavctp_tree, hf_btavctp_ipid,  tvb, offset, 1, ENC_BIG_ENDIAN);
 158         ipid = tvb_get_uint8(tvb, offset) & 0x01;
 159     } else {
 160         proto_tree_add_item(btavctp_tree, hf_btavctp_rfa,  tvb, offset, 1, ENC_BIG_ENDIAN);
 161     }
 162     offset++;
 163
 164     if (packet_type == PACKET_TYPE_START) {
 165         proto_tree_add_item(btavctp_tree, hf_btavctp_number_of_packets,  tvb, offset, 1, ENC_BIG_ENDIAN);
 166         number_of_packets = tvb_get_uint8(tvb, offset);
 167         offset++;
 168     }
 169
 170     if (packet_type == PACKET_TYPE_SINGLE || packet_type == PACKET_TYPE_START) {
 171         proto_tree_add_item(btavctp_tree, hf_btavctp_pid,  tvb, offset, 2, ENC_BIG_ENDIAN);
 172         pid = tvb_get_ntohs(tvb, offset);
 173
 174         if (p_get_proto_data(pinfo->pool, pinfo, proto_bluetooth, PROTO_DATA_BLUETOOTH_SERVICE_UUID ) == NULL) {
 175             uint8_t *value_data;
 176             bluetooth_uuid_t  uuid;
 177
 178             uuid.size = 2;
 179             uuid.bt_uuid = pid;
 180             uuid.data[0] = pid >> 8;
 181             uuid.data[1] = pid & 0xFF;
 182
 183             value_data = wmem_strdup(wmem_file_scope(), print_numeric_bluetooth_uuid(pinfo->pool, &uuid));
 184
 185             p_add_proto_data(pinfo->pool, pinfo, proto_bluetooth, PROTO_DATA_BLUETOOTH_SERVICE_UUID, value_data);
 186         }
 187         offset +=2;
 188     }
 189
 190     col_append_fstr(pinfo->cinfo, COL_INFO, "%s - Transaction: %u, PacketType: %s",
 191             val_to_str_const(cr, cr_vals, "unknown CR"), transaction,
 192             val_to_str_const(packet_type, packet_type_vals, "unknown packet type"));
 193
 194     if (ipid) {
 195         expert_add_info(pinfo, ipid_item, &ei_btavctp_invalid_profile);
 196         col_append_sep_str(pinfo->cinfo, COL_INFO, NULL, "Invalid profile");
 197         if (tvb_captured_length_remaining(tvb, offset) == 0)
 198             return offset;
 199     }
 200
 201     avctp_data = wmem_new(pinfo->pool, btavctp_data_t);
 202     avctp_data->cr           = cr;
 203     avctp_data->interface_id = interface_id;
 204     avctp_data->adapter_id   = adapter_id;
 205     avctp_data->chandle      = chandle;
 206     avctp_data->psm          = psm;
 207
 208     length = tvb_reported_length_remaining(tvb, offset);
 209
 210     /* reassembling */
 211     next_tvb = tvb_new_subset_length(tvb, offset, length);
 212     if (packet_type == PACKET_TYPE_SINGLE) {
 213         bluetooth_uuid_t  uuid;
 214
 215         uuid.size = 2;
 216         uuid.bt_uuid = pid;
 217         uuid.data[0] = pid >> 8;
 218         uuid.data[1] = pid & 0xFF;
 219
 220         if (!dissector_try_string_with_data(bluetooth_uuid_table, print_numeric_bluetooth_uuid(pinfo->pool, &uuid), next_tvb, pinfo, tree, true, avctp_data)) {
 221             call_data_dissector(next_tvb, pinfo, tree);
 222         }
 223
 224     } else {
 225         fragment_t     *fragment;
 226         wmem_tree_key_t key[6];
 227         uint32_t        frame_number;
 228
 229         frame_number = pinfo->num;
 230
 231         key[0].length = 1;
 232         key[0].key = &interface_id;
 233         key[1].length = 1;
 234         key[1].key = &adapter_id;
 235         key[2].length = 1;
 236         key[2].key = &chandle;
 237         key[3].length = 1;
 238         key[3].key = &psm;
 239         key[4].length = 1;
 240         key[4].key = &frame_number;
 241         key[5].length = 0;
 242         key[5].key = NULL;
 243
 244         if (packet_type == PACKET_TYPE_START) {
 245             if (!pinfo->fd->visited) {
 246                 fragment = wmem_new(wmem_file_scope(), fragment_t);
 247                 fragment->length = length;
 248                 fragment->data = (uint8_t *) wmem_alloc(wmem_file_scope(), fragment->length);
 249                 tvb_memcpy(tvb, fragment->data, offset, fragment->length);
 250
 251                 fragments = wmem_new(wmem_file_scope(), fragments_t);
 252                 fragments->number_of_packets = number_of_packets;
 253                 fragments->pid = pid;
 254
 255                 fragments->count = 1;
 256                 fragments->fragment = wmem_tree_new(wmem_file_scope());
 257                 wmem_tree_insert32(fragments->fragment, fragments->count, fragment);
 258
 259                 fragments->interface_id = interface_id;
 260                 fragments->adapter_id   = adapter_id;
 261                 fragments->chandle      = chandle;
 262                 fragments->psm          = psm;
 263
 264                 wmem_tree_insert32_array(reassembling, key, fragments);
 265
 266             } else {
 267                 fragments = (fragments_t *)wmem_tree_lookup32_array_le(reassembling, key);
 268                 if (!(fragments && fragments->interface_id == interface_id &&
 269                         fragments->adapter_id == adapter_id &&
 270                         fragments->chandle == chandle &&
 271                         fragments->psm == psm))
 272                     fragments = NULL;
 273             }
 274
 275             call_data_dissector(next_tvb, pinfo, tree);
 276
 277         } else if (packet_type == PACKET_TYPE_CONTINUE) {
 278             fragments = (fragments_t *)wmem_tree_lookup32_array_le(reassembling, key);
 279             if (!(fragments && fragments->interface_id == interface_id &&
 280                     fragments->adapter_id == adapter_id &&
 281                     fragments->chandle == chandle &&
 282                     fragments->psm == psm))
 283                 fragments = NULL;
 284
 285             if (!pinfo->fd->visited && fragments != NULL) {
 286                 fragment = wmem_new(wmem_file_scope(), fragment_t);
 287                 fragment->length = length;
 288                 fragment->data = (uint8_t *) wmem_alloc(wmem_file_scope(), fragment->length);
 289                 tvb_memcpy(tvb, fragment->data, offset, fragment->length);
 290
 291                 fragments->count++;
 292                 wmem_tree_insert32(fragments->fragment, fragments->count, fragment);
 293
 294                 fragments->interface_id = interface_id;
 295                 fragments->adapter_id   = adapter_id;
 296                 fragments->chandle      = chandle;
 297                 fragments->psm          = psm;
 298
 299                 frame_number = pinfo->num;
 300
 301                 key[0].length = 1;
 302                 key[0].key = &interface_id;
 303                 key[1].length = 1;
 304                 key[1].key = &adapter_id;
 305                 key[2].length = 1;
 306                 key[2].key = &chandle;
 307                 key[3].length = 1;
 308                 key[3].key = &psm;
 309                 key[4].length = 1;
 310                 key[4].key = &frame_number;
 311                 key[5].length = 0;
 312                 key[5].key = NULL;
 313
 314                 wmem_tree_insert32_array(reassembling, key, fragments);
 315             }
 316
 317             call_data_dissector(next_tvb, pinfo, tree);
 318
 319         } else if (packet_type == PACKET_TYPE_END) {
 320
 321             fragments = (fragments_t *)wmem_tree_lookup32_array_le(reassembling, key);
 322             if (!(fragments && fragments->interface_id == interface_id &&
 323                     fragments->adapter_id == adapter_id &&
 324                     fragments->chandle == chandle &&
 325                     fragments->psm == psm))
 326                 fragments = NULL;
 327
 328             if (!pinfo->fd->visited && fragments != NULL) {
 329                 fragment = wmem_new(wmem_file_scope(), fragment_t);
 330                 fragment->length = length;
 331                 fragment->data = (uint8_t *) wmem_alloc(wmem_file_scope(), fragment->length);
 332                 tvb_memcpy(tvb, fragment->data, offset, fragment->length);
 333
 334                 fragments->count++;
 335                 wmem_tree_insert32(fragments->fragment, fragments->count, fragment);
 336
 337                 fragments->interface_id = interface_id;
 338                 fragments->adapter_id   = adapter_id;
 339                 fragments->chandle      = chandle;
 340                 fragments->psm          = psm;
 341
 342                 frame_number = pinfo->num;
 343
 344                 key[0].length = 1;
 345                 key[0].key = &interface_id;
 346                 key[1].length = 1;
 347                 key[1].key = &adapter_id;
 348                 key[2].length = 1;
 349                 key[2].key = &chandle;
 350                 key[3].length = 1;
 351                 key[3].key = &psm;
 352                 key[4].length = 1;
 353                 key[4].key = &frame_number;
 354                 key[5].length = 0;
 355                 key[5].key = NULL;
 356
 357                 wmem_tree_insert32_array(reassembling, key, fragments);
 358             }
 359
 360             length = 0;
 361             if (!fragments || fragments->count != fragments->number_of_packets) {
 362                 expert_add_info(pinfo, pitem, &ei_btavctp_unexpected_frame);
 363                 call_data_dissector(next_tvb, pinfo, tree);
 364             } else {
 365                 uint8_t  *reassembled = NULL;
 366                 bluetooth_uuid_t  uuid;
 367
 368                 for (i_frame = 1; i_frame <= fragments->count; ++i_frame) {
 369                     fragment = (fragment_t *)wmem_tree_lookup32_le(fragments->fragment, i_frame);
 370                     if (fragment) {
 371                         reassembled = (uint8_t*)wmem_realloc(pinfo->pool, reassembled, length + fragment->length);
 372                         memcpy(reassembled + length, fragment->data, fragment->length);
 373                         length += fragment->length;
 374                     }
 375                 }
 376
 377                 next_tvb = tvb_new_child_real_data(tvb, reassembled, length, length);
 378                 add_new_data_source(pinfo, next_tvb, "Reassembled AVCTP");
 379
 380                 uuid.size = 2;
 381                 uuid.bt_uuid = fragments->pid;
 382                 uuid.data[0] = fragments->pid >> 8;
 383                 uuid.data[1] = fragments->pid & 0xFF;
 384
 385                 if (!dissector_try_string_with_data(bluetooth_uuid_table, print_numeric_bluetooth_uuid(pinfo->pool, &uuid), next_tvb, pinfo, tree, true, avctp_data)) {
 386                     call_data_dissector(next_tvb, pinfo, tree);
 387                 }
 388             }
 389
 390             fragments = NULL;
 391         } else {
 392             call_data_dissector(next_tvb, pinfo, tree);
 393         }
 394     }
 395
 396     return offset;
 397 }
 398
 399 void
 400 proto_register_btavctp(void)
 401 {
 402     module_t *module;
 403     expert_module_t* expert_btavctp;
 404
 405     static hf_register_info hf[] = {
 406         { &hf_btavctp_transaction,
 407             { "Transaction",          "btavctp.transaction",
 408             FT_UINT8, BASE_HEX, NULL, 0xF0,
 409             NULL, HFILL }
 410         },
 411         { &hf_btavctp_packet_type,
 412             { "Packet Type",          "btavctp.packet_type",
 413             FT_UINT8, BASE_HEX, VALS(packet_type_vals), 0x0C,
 414             NULL, HFILL }
 415         },
 416         { &hf_btavctp_cr,
 417             { "C/R",                  "btavctp.cr",
 418             FT_UINT8, BASE_HEX, VALS(cr_vals), 0x02,
 419             NULL, HFILL }
 420         },
 421         { &hf_btavctp_ipid,
 422             { "IPID",                 "btavctp.ipid",
 423             FT_UINT8, BASE_HEX, VALS(ipid_vals), 0x01,
 424             NULL, HFILL }
 425         },
 426         { &hf_btavctp_rfa,
 427             { "RFA",                  "btavctp.rfa",
 428             FT_UINT8, BASE_HEX, NULL, 0x01,
 429             NULL, HFILL }
 430         },
 431         { &hf_btavctp_pid,
 432             { "Profile Identifier",   "btavctp.pid",
 433             FT_UINT16, BASE_HEX|BASE_EXT_STRING, &bluetooth_uuid_vals_ext, 0x00,
 434             NULL, HFILL }
 435         },
 436         { &hf_btavctp_number_of_packets,
 437             { "Number of packets",    "btavctp.nop",
 438             FT_UINT8, BASE_DEC, NULL, 0x00,
 439             NULL, HFILL }
 440         }
 441     };
 442
 443     static int *ett[] = {
 444         &ett_btavctp
 445     };
 446
 447     static ei_register_info ei[] = {
 448         { &ei_btavctp_unexpected_frame, { "btavctp.unexpected_frame", PI_PROTOCOL, PI_WARN, "Unexpected frame", EXPFILL }},
 449         { &ei_btavctp_invalid_profile,  { "btavctp.invalid_profile",  PI_PROTOCOL, PI_NOTE, "Invalid Profile", EXPFILL }},
 450     };
 451
 452     /* Decode As handling */
 453     reassembling = wmem_tree_new_autoreset(wmem_epan_scope(), wmem_file_scope());
 454
 455     proto_btavctp = proto_register_protocol("Bluetooth AVCTP Protocol", "BT AVCTP", "btavctp");
 456     btavctp_handle = register_dissector("btavctp", dissect_btavctp, proto_btavctp);
 457
 458     proto_register_field_array(proto_btavctp, hf, array_length(hf));
 459     proto_register_subtree_array(ett, array_length(ett));
 460     expert_btavctp = expert_register_protocol(proto_btavctp);
 461     expert_register_field_array(expert_btavctp, ei, array_length(ei));
 462
 463     module = prefs_register_protocol_subtree("Bluetooth", proto_btavctp, NULL);
 464     prefs_register_static_text_preference(module, "avctp.version",
 465             "Bluetooth Protocol AVCTP version: 1.4",
 466             "Version of protocol supported by this dissector.");
 467 }
 468
 469
 470 void
 471 proto_reg_handoff_btavctp(void)
 472 {
 473     dissector_add_string("bluetooth.uuid", "17", btavctp_handle);
 474
 475     dissector_add_uint("btl2cap.psm", BTL2CAP_PSM_AVCTP_CTRL, btavctp_handle);
 476     dissector_add_uint("btl2cap.psm", BTL2CAP_PSM_AVCTP_BRWS, btavctp_handle);
 477
 478     dissector_add_for_decode_as("btl2cap.cid", btavctp_handle);
 479 }
 480
 481 /*
 482  * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 483  *
 484  * Local variables:
 485  * c-basic-offset: 4
 486  * tab-width: 8
 487  * indent-tabs-mode: nil
 488  * End:
 489  *
 490  * vi: set shiftwidth=4 tabstop=8 expandtab:
 491  * :indentSize=4:tabSize=8:noTabs=true:
 492  */