1 /* packet-btbb.c 2 * Routines for Bluetooth baseband dissection 3 * Copyright 2009, Michael Ossmann <[email protected]> 4 * 5 * $Id$ 6 * 7 * Wireshark - Network traffic analyzer 8 * By Gerald Combs <[email protected]> 9 * Copyright 1998 Gerald Combs 10 * 11 * This program is free software; you can redistribute it and/or 12 * modify it under the terms of the GNU General Public License 13 * as published by the Free Software Foundation; either version 2 14 * of the License, or (at your option) any later version. 15 * 16 * This program is distributed in the hope that it will be useful, 17 * but WITHOUT ANY WARRANTY; without even the implied warranty of 18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19 * GNU General Public License for more details. 20 * 21 * You should have received a copy of the GNU General Public License 22 * along with this program; if not, write to the Free Software 23 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. 24 */ 25 26 #ifdef HAVE_CONFIG_H 27 # include "config.h" 28 #endif 29 30 #include <wireshark/config.h> /* needed for epan/gcc-4.x */ 31 #include <epan/packet.h> 32 #include <epan/prefs.h> 33 34 /* function prototypes */ 35 void proto_reg_handoff_btbb(void); 36 37 /* initialize the protocol and registered fields */ 38 static int proto_btbb = -1; 39 static int hf_btbb_meta = -1; 40 static int hf_btbb_dir = -1; 41 static int hf_btbb_clk = -1; 42 static int hf_btbb_channel = -1; 43 static int hf_btbb_addrbits = -1; 44 static int hf_btbb_clkbits = -1; 45 static int hf_btbb_pkthdr = -1; 46 static int hf_btbb_ltaddr = -1; 47 static int hf_btbb_type = -1; 48 static int hf_btbb_flags = -1; 49 static int hf_btbb_flow = -1; 50 static int hf_btbb_arqn = -1; 51 static int hf_btbb_seqn = -1; 52 static int hf_btbb_hec = -1; 53 static int hf_btbb_payload = -1; 54 static int hf_btbb_pldhdr = -1; 55 static int hf_btbb_llid = -1; 56 static int hf_btbb_pldflow = -1; 57 static int hf_btbb_length = -1; 58 static int hf_btbb_pldbody = -1; 59 static int hf_btbb_crc = -1; 60 static int hf_btbb_fhs_parity = -1; 61 static int hf_btbb_fhs_lap = -1; 62 static int hf_btbb_fhs_eir = -1; 63 static int hf_btbb_fhs_sr = -1; 64 static int hf_btbb_fhs_uap = -1; 65 static int hf_btbb_fhs_nap = -1; 66 static int hf_btbb_fhs_class = -1; 67 static int hf_btbb_fhs_ltaddr = -1; 68 static int hf_btbb_fhs_clk = -1; 69 static int hf_btbb_fhs_psmode = -1; 70 71 /* field values */ 72 static const true_false_string direction = { 73 "Slave to Master", 74 "Master to Slave" 75 }; 76 77 static const true_false_string clock_bits = { 78 "27", 79 "6" 80 }; 81 82 static const true_false_string address_bits = { 83 "48 (NAP known)", 84 "32 (NAP unknown)" 85 }; 86 87 static const value_string packet_types[] = { 88 /* generic names for unknown logical transport */ 89 { 0x0, "NULL" }, 90 { 0x1, "POLL" }, 91 { 0x2, "FHS" }, 92 { 0x3, "DM1" }, 93 { 0x4, "DH1/2-DH1" }, 94 { 0x5, "HV1" }, 95 { 0x6, "HV2/2-EV3" }, 96 { 0x7, "HV3/EV3/3-EV3" }, 97 { 0x8, "DV/3-DH1" }, 98 { 0x9, "AUX1" }, 99 { 0xa, "DM3/2-DH3" }, 100 { 0xb, "DH3/3-DH3" }, 101 { 0xc, "EV4/2-EV5" }, 102 { 0xd, "EV5/3-EV5" }, 103 { 0xe, "DM5/2-DH5" }, 104 { 0xf, "DH5/3-DH5" }, 105 { 0, NULL } 106 }; 107 108 static const value_string sr_modes[] = { 109 { 0x0, "R0" }, 110 { 0x1, "R1" }, 111 { 0x2, "R2" }, 112 { 0x3, "Reserved" }, 113 { 0, NULL } 114 }; 115 116 static const range_string ps_modes[] = { 117 { 0x0, 0x0, "Mandatory scan mode" }, 118 { 0x1, 0x7, "Reserved" }, 119 { 0, 0, NULL } 120 }; 121 122 static const value_string llid_codes[] = { 123 { 0x0, "undefined" }, 124 { 0x1, "Continuation fragment of an L2CAP message (ACL-U)" }, 125 { 0x2, "Start of an L2CAP message or no fragmentation (ACL-U)" }, 126 { 0x3, "LMP message (ACL-C)" }, 127 { 0, NULL } 128 }; 129 130 /* initialize the subtree pointers */ 131 static gint ett_btbb = -1; 132 static gint ett_btbb_meta = -1; 133 static gint ett_btbb_pkthdr = -1; 134 static gint ett_btbb_flags = -1; 135 static gint ett_btbb_payload = -1; 136 static gint ett_btbb_pldhdr = -1; 137 138 /* subdissectors */ 139 static dissector_handle_t btlmp_handle = NULL; 140 static dissector_handle_t btl2cap_handle = NULL; 141 142 /* packet header flags */ 143 static const int *flag_fields[] = { 144 &hf_btbb_flow, 145 &hf_btbb_arqn, 146 &hf_btbb_seqn, 147 NULL 148 }; 149 150 /* one byte payload header */ 151 int 152 dissect_payload_header1(proto_tree *tree, tvbuff_t *tvb, int offset) 153 { 154 proto_item *hdr_item; 155 proto_tree *hdr_tree; 156 157 DISSECTOR_ASSERT(tvb_length_remaining(tvb, offset) >= 1); 158 159 hdr_item = proto_tree_add_item(tree, hf_btbb_pldhdr, tvb, offset, 1, TRUE); 160 hdr_tree = proto_item_add_subtree(hdr_item, ett_btbb_pldhdr); 161 162 proto_tree_add_item(hdr_tree, hf_btbb_llid, tvb, offset, 1, TRUE); 163 proto_tree_add_item(hdr_tree, hf_btbb_pldflow, tvb, offset, 1, TRUE); 164 proto_tree_add_item(hdr_tree, hf_btbb_length, tvb, offset, 1, TRUE); 165 166 /* payload length */ 167 return tvb_get_guint8(tvb, offset) >> 3; 168 } 169 170 void 171 dissect_fhs(proto_tree *tree, tvbuff_t *tvb, int offset) 172 { 173 proto_item *fhs_item; 174 proto_tree *fhs_tree; 175 176 DISSECTOR_ASSERT(tvb_length_remaining(tvb, offset) == 20); 177 178 fhs_item = proto_tree_add_item(tree, hf_btbb_payload, tvb, offset, -1, TRUE); 179 fhs_tree = proto_item_add_subtree(fhs_item, ett_btbb_payload); 180 181 proto_tree_add_item(fhs_tree, hf_btbb_fhs_parity, tvb, offset, 5, TRUE); 182 offset += 4; 183 184 proto_tree_add_item(fhs_tree, hf_btbb_fhs_lap, tvb, offset, 4, TRUE); 185 offset += 3; 186 187 proto_tree_add_item(fhs_tree, hf_btbb_fhs_eir, tvb, offset, 1, TRUE); 188 /* skipping 1 undefined bit */ 189 proto_tree_add_item(fhs_tree, hf_btbb_fhs_sr, tvb, offset, 1, TRUE); 190 /* skipping 2 reserved bits */ 191 offset += 1; 192 193 proto_tree_add_item(fhs_tree, hf_btbb_fhs_uap, tvb, offset, 1, TRUE); 194 offset += 1; 195 196 proto_tree_add_item(fhs_tree, hf_btbb_fhs_nap, tvb, offset, 2, TRUE); 197 offset += 2; 198 199 proto_tree_add_item(fhs_tree, hf_btbb_fhs_class, tvb, offset, 3, TRUE); 200 offset += 3; 201 202 proto_tree_add_item(fhs_tree, hf_btbb_fhs_ltaddr, tvb, offset, 1, TRUE); 203 proto_tree_add_item(fhs_tree, hf_btbb_fhs_clk, tvb, offset, 4, TRUE); 204 offset += 3; 205 206 proto_tree_add_item(fhs_tree, hf_btbb_fhs_psmode, tvb, offset, 1, TRUE); 207 offset += 1; 208 209 proto_tree_add_item(fhs_tree, hf_btbb_crc, tvb, offset, 2, TRUE); 210 offset += 2; 211 } 212 213 void 214 dissect_dm1(proto_tree *tree, tvbuff_t *tvb, packet_info *pinfo, int offset) 215 { 216 int len; /* payload length indicated by payload header */ 217 int llid; /* logical link id */ 218 int l2len; /* length indicated by l2cap header */ 219 proto_item *dm1_item; 220 proto_tree *dm1_tree; 221 tvbuff_t *pld_tvb; 222 223 /* 224 * FIXME 225 * I'm probably doing a terrible, terrible thing here, but it gets my 226 * initial test cases working. 227 */ 228 guint16 fake_acl_data; 229 230 DISSECTOR_ASSERT(tvb_length_remaining(tvb, offset) >= 3); 231 232 dm1_item = proto_tree_add_item(tree, hf_btbb_payload, tvb, offset, -1, TRUE); 233 dm1_tree = proto_item_add_subtree(dm1_item, ett_btbb_payload); 234 235 len = dissect_payload_header1(dm1_tree, tvb, offset); 236 llid = tvb_get_guint8(tvb, offset) & 0x3; 237 offset += 1; 238 239 DISSECTOR_ASSERT(tvb_length_remaining(tvb, offset) == len + 2); 240 241 if (llid == 3 && btlmp_handle) { 242 /* LMP */ 243 pld_tvb = tvb_new_subset(tvb, offset, len, len); 244 call_dissector(btlmp_handle, pld_tvb, pinfo, dm1_tree); 245 } else if (llid == 2 && btl2cap_handle) { 246 /* unfragmented L2CAP or start of fragment */ 247 l2len = tvb_get_letohs(tvb, offset); 248 if (l2len + 4 == len) { 249 /* unfragmented */ 250 pinfo->private_data = &fake_acl_data; 251 pld_tvb = tvb_new_subset(tvb, offset, len, len); 252 call_dissector(btl2cap_handle, pld_tvb, pinfo, dm1_tree); 253 } else { 254 /* start of fragment */ 255 proto_tree_add_item(dm1_tree, hf_btbb_pldbody, tvb, offset, len, TRUE); 256 } 257 } else { 258 proto_tree_add_item(dm1_tree, hf_btbb_pldbody, tvb, offset, len, TRUE); 259 } 260 offset += len; 261 262 proto_tree_add_item(dm1_tree, hf_btbb_crc, tvb, offset, 2, TRUE); 263 offset += 2; 264 } 265 266 /* dissect a packet */ 267 static int 268 dissect_btbb(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) 269 { 270 proto_item *btbb_item, *meta_item, *pkthdr_item, *pld_item; 271 proto_tree *btbb_tree, *meta_tree, *pkthdr_tree; 272 int offset; 273 guint8 type; 274 char *info; 275 276 /* sanity check: length */ 277 if (tvb_length(tvb) > 0 && tvb_length(tvb) < 9) 278 /* bad length: look for a different dissector */ 279 return 0; 280 281 /* maybe should verify HEC */ 282 283 /* make entries in protocol column and info column on summary display */ 284 if (check_col(pinfo->cinfo, COL_PROTOCOL)) 285 col_set_str(pinfo->cinfo, COL_PROTOCOL, "Bluetooth"); 286 287 if (tvb_length(tvb) == 0) { 288 info = "ID"; 289 } else { 290 type = (tvb_get_guint8(tvb, 6) >> 3) & 0x0f; 291 info = match_strval(type, packet_types); 292 } 293 294 if (check_col(pinfo->cinfo, COL_INFO)) { 295 col_clear(pinfo->cinfo, COL_INFO); 296 col_add_str(pinfo->cinfo, COL_INFO, info); 297 } 298 299 /* see if we are being asked for details */ 300 if (tree) { 301 302 /* create display subtree for the protocol */ 303 offset = 0; 304 btbb_item = proto_tree_add_item(tree, proto_btbb, tvb, offset, -1, TRUE); 305 btbb_tree = proto_item_add_subtree(btbb_item, ett_btbb); 306 307 /* ID packets have no header, no payload */ 308 if (tvb_length(tvb) == 0) 309 return 1; 310 311 /* meta data */ 312 meta_item = proto_tree_add_item(btbb_tree, hf_btbb_meta, tvb, offset, 3, TRUE); 313 meta_tree = proto_item_add_subtree(meta_item, ett_btbb_meta); 314 315 proto_tree_add_item(meta_tree, hf_btbb_dir, tvb, offset, 1, TRUE); 316 proto_tree_add_item(meta_tree, hf_btbb_clk, tvb, offset, 4, TRUE); 317 offset += 4; 318 319 proto_tree_add_item(meta_tree, hf_btbb_channel, tvb, offset, 1, TRUE); 320 offset += 1; 321 322 proto_tree_add_item(meta_tree, hf_btbb_clkbits, tvb, offset, 1, TRUE); 323 proto_tree_add_item(meta_tree, hf_btbb_addrbits, tvb, offset, 1, TRUE); 324 offset += 1; 325 326 /* packet header */ 327 pkthdr_item = proto_tree_add_item(btbb_tree, hf_btbb_pkthdr, tvb, offset, 3, TRUE); 328 pkthdr_tree = proto_item_add_subtree(pkthdr_item, ett_btbb_pkthdr); 329 330 proto_tree_add_item(pkthdr_tree, hf_btbb_ltaddr, tvb, offset, 1, TRUE); 331 proto_tree_add_item(pkthdr_tree, hf_btbb_type, tvb, offset, 1, TRUE); 332 offset += 1; 333 proto_tree_add_bitmask(pkthdr_tree, tvb, offset, hf_btbb_flags, 334 ett_btbb_flags, flag_fields, TRUE); 335 offset += 1; 336 proto_tree_add_item(pkthdr_tree, hf_btbb_hec, tvb, offset, 1, TRUE); 337 offset += 1; 338 339 /* payload */ 340 switch (type) { 341 case 0x0: /* NULL */ 342 case 0x1: /* POLL */ 343 break; 344 case 0x2: /* FHS */ 345 dissect_fhs(btbb_tree, tvb, offset); 346 break; 347 case 0x3: /* DM1 */ 348 dissect_dm1(btbb_tree, tvb, pinfo, offset); 349 break; 350 case 0x4: /* DH1/2-DH1 */ 351 dissect_dm1(btbb_tree, tvb, pinfo, offset); 352 break; 353 case 0x5: /* HV1 */ 354 case 0x6: /* HV2/2-EV3 */ 355 case 0x7: /* HV3/EV3/3-EV3 */ 356 case 0x8: /* DV/3-DH1 */ 357 case 0x9: /* AUX1 */ 358 case 0xa: /* DM3/2-DH3 */ 359 case 0xb: /* DH3/3-DH3 */ 360 case 0xc: /* EV4/2-EV5 */ 361 case 0xd: /* EV5/3-EV5 */ 362 case 0xe: /* DM5/2-DH5 */ 363 case 0xf: /* DH5/3-DH5 */ 364 pld_item = proto_tree_add_item(btbb_tree, hf_btbb_payload, tvb, offset, -1, TRUE); 365 break; 366 default: 367 break; 368 } 369 } 370 371 /* Return the amount of data this dissector was able to dissect */ 372 return tvb_length(tvb); 373 } 374 375 /* register the protocol with Wireshark */ 376 void 377 proto_register_btbb(void) 378 { 379 380 /* list of fields */ 381 static hf_register_info hf[] = { 382 { &hf_btbb_meta, 383 { "Meta Data", "btbb.meta", 384 FT_NONE, BASE_NONE, NULL, 0x0, 385 "Meta Data About the Packet", HFILL } 386 }, 387 { &hf_btbb_dir, 388 { "Direction", "btbb.dir", 389 FT_BOOLEAN, BASE_NONE, TFS(&direction), 0x01, 390 "Direction of Transmission", HFILL } 391 }, 392 { &hf_btbb_clk, 393 { "CLK", "btbb.clk", 394 FT_UINT32, BASE_HEX, NULL, 0x0, 395 "Clock bits 1 through 27", HFILL } 396 }, 397 { &hf_btbb_channel, 398 { "Channel", "btbb.channel", 399 FT_UINT8, BASE_DEC, NULL, 0x0, 400 "Channel (0-78)", HFILL } 401 }, 402 { &hf_btbb_clkbits, 403 { "Known Clock Bits ", "btbb.clkbits", 404 FT_BOOLEAN, BASE_NONE, TFS(&clock_bits), 0x01, 405 "Number of Known Master CLK Bits (6 or 27)", HFILL } 406 }, 407 { &hf_btbb_addrbits, 408 { "Known Address Bits ", "btbb.addrbits", 409 FT_BOOLEAN, BASE_NONE, TFS(&address_bits), 0x02, 410 "Number of Known Bits of BD_ADDR (32 or 48)", HFILL } 411 }, 412 { &hf_btbb_pkthdr, 413 { "Packet Header", "btbb.pkthdr", 414 FT_NONE, BASE_NONE, NULL, 0x0, 415 "Bluetooth Baseband Packet Header", HFILL } 416 }, 417 { &hf_btbb_ltaddr, 418 { "LT_ADDR", "btbb.lt_addr", 419 FT_UINT8, BASE_HEX, NULL, 0x07, 420 "Logical Transport Address", HFILL } 421 }, 422 { &hf_btbb_type, 423 { "TYPE", "btbb.type", 424 FT_UINT8, BASE_HEX, VALS(packet_types), 0x78, 425 "Packet Type", HFILL } 426 }, 427 { &hf_btbb_flags, 428 { "Flags", "btbb.flags", 429 FT_UINT8, BASE_HEX, NULL, 0x0, 430 "Packet Header Flags", HFILL } 431 }, 432 { &hf_btbb_flow, 433 { "FLOW", "btbb.flow", 434 FT_BOOLEAN, 8, NULL, 0x01, 435 "Flow control indication", HFILL } 436 }, 437 { &hf_btbb_arqn, 438 { "ARQN", "btbb.arqn", 439 FT_BOOLEAN, 8, NULL, 0x02, 440 "Acknowledgment indication", HFILL } 441 }, 442 { &hf_btbb_seqn, 443 { "SEQN", "btbb.seqn", 444 FT_BOOLEAN, 8, NULL, 0x04, 445 "Sequence number", HFILL } 446 }, 447 { &hf_btbb_hec, 448 { "HEC", "btbb.lt_addr", 449 FT_UINT8, BASE_HEX, NULL, 0x0, 450 "Header Error Check", HFILL } 451 }, 452 { &hf_btbb_payload, 453 { "Payload", "btbb.payload", 454 FT_NONE, BASE_NONE, NULL, 0x0, 455 "Payload", HFILL } 456 }, 457 { &hf_btbb_llid, 458 { "LLID", "btbb.llid", 459 FT_UINT8, BASE_HEX, VALS(llid_codes), 0x03, 460 "Logical Link ID", HFILL } 461 }, 462 { &hf_btbb_pldflow, 463 { "Flow", "btbb.flow", 464 FT_BOOLEAN, BASE_NONE, NULL, 0x04, 465 "Payload Flow indication", HFILL } 466 }, 467 { &hf_btbb_length, 468 { "Length", "btbb.length", 469 FT_UINT8, BASE_DEC, NULL, 0xf8, 470 "Payload Length", HFILL } 471 }, 472 { &hf_btbb_pldhdr, 473 { "Payload Header", "btbb.pldhdr", 474 FT_NONE, BASE_NONE, NULL, 0x0, 475 "Payload Header", HFILL } 476 }, 477 { &hf_btbb_pldbody, 478 { "Payload Body", "btbb.pldbody", 479 FT_BYTES, BASE_NONE, NULL, 0x0, 480 "Payload Body", HFILL } 481 }, 482 { &hf_btbb_crc, 483 { "CRC", "btbb.crc", 484 FT_UINT16, BASE_HEX, NULL, 0x0, 485 "Payload CRC", HFILL } 486 }, 487 { &hf_btbb_fhs_parity, 488 { "Parity", "btbb.parity", 489 /* FIXME not sure why this mask doesn't have an effect. bug? */ 490 FT_UINT64, BASE_HEX, NULL, 0x00000003ffffffff, 491 "LAP parity", HFILL } 492 }, 493 { &hf_btbb_fhs_lap, 494 { "LAP", "btbb.lap", 495 FT_UINT24, BASE_HEX, NULL, 0x03fffffc, 496 "Lower Address Part", HFILL } 497 }, 498 { &hf_btbb_fhs_eir, 499 { "EIR", "btbb.eir", 500 FT_BOOLEAN, BASE_NONE, NULL, 0x04, 501 "Extended Inquiry Response packet may follow", HFILL } 502 }, 503 { &hf_btbb_fhs_sr, 504 { "SR", "btbb.sr", 505 FT_UINT8, BASE_HEX, VALS(sr_modes), 0x30, 506 "Scan Repetition", HFILL } 507 }, 508 { &hf_btbb_fhs_uap, 509 { "UAP", "btbb.uap", 510 FT_UINT8, BASE_HEX, NULL, 0x0, 511 "Upper Address Part", HFILL } 512 }, 513 { &hf_btbb_fhs_nap, 514 { "NAP", "btbb.nap", 515 FT_UINT16, BASE_HEX, NULL, 0x0, 516 "Non-Significant Address Part", HFILL } 517 }, 518 { &hf_btbb_fhs_class, /* FIXME break out further */ 519 { "Class of Device", "btbb.class", 520 FT_UINT24, BASE_HEX, NULL, 0x0, 521 "Class of Device", HFILL } 522 }, 523 { &hf_btbb_fhs_ltaddr, 524 { "LT_ADDR", "btbb.lt_addr", 525 FT_UINT8, BASE_HEX, NULL, 0x07, 526 "Logical Transport Address", HFILL } 527 }, 528 { &hf_btbb_fhs_clk, 529 { "CLK", "btbb.clk", 530 FT_UINT32, BASE_HEX, NULL, 0x1ffffff8, 531 "Clock bits 2 through 27", HFILL } 532 }, 533 { &hf_btbb_fhs_psmode, 534 { "Page Scan Mode", "btbb.psmode", 535 FT_UINT8, BASE_HEX, RVALS(ps_modes), 0xe0, 536 "Page Scan Mode", HFILL } 537 }, 538 }; 539 540 /* protocol subtree arrays */ 541 static gint *ett[] = { 542 &ett_btbb, 543 &ett_btbb_meta, 544 &ett_btbb_pkthdr, 545 &ett_btbb_flags, 546 &ett_btbb_payload, 547 &ett_btbb_pldhdr, 548 }; 549 550 /* register the protocol name and description */ 551 proto_btbb = proto_register_protocol( 552 "Bluetooth Baseband", /* full name */ 553 "btbb", /* short name */ 554 "btbb" /* abbreviation (e.g. for filters) */ 555 ); 556 557 /* register the header fields and subtrees used */ 558 proto_register_field_array(proto_btbb, hf, array_length(hf)); 559 proto_register_subtree_array(ett, array_length(ett)); 560 } 561 562 void 563 proto_reg_handoff_btbb(void) 564 { 565 static gboolean inited = FALSE; 566 567 if (!inited) { 568 dissector_handle_t btbb_handle; 569 570 btbb_handle = new_create_dissector_handle(dissect_btbb, proto_btbb); 571 /* hijacking this ethertype */ 572 dissector_add("ethertype", 0xFFF0, btbb_handle); 573 574 btlmp_handle = find_dissector("btlmp"); 575 btl2cap_handle = find_dissector("btl2cap"); 576 577 inited = TRUE; 578 } 579 } 580