wiretap/btsnoop.c

   1 /* btsnoop.c
   2  *
   3  * $Id$
   4  *
   5  * Wiretap Library
   6  * Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License
  10  * as published by the Free Software Foundation; either version 2
  11  * of the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  21  */
  22
  23 #include "config.h"
  24 #include <errno.h>
  25 #include <string.h>
  26 #include "wtap-int.h"
  27 #include "file_wrappers.h"
  28 #include "buffer.h"
  29 #include "atm.h"
  30 #include "btsnoop.h"
  31
  32 /*
  33  * Symbian's btsnoop format is derived from Sun's snoop format.
  34  * See RFC 1761 for a description of the "snoop" file format.
  35  */
  36
  37 /* Magic number in "btsnoop" files. */
  38 static const char btsnoop_magic[] = {
  39         'b', 't', 's', 'n', 'o', 'o', 'p', '\0'
  40 };
  41
  42 /* "btsnoop" file header (minus magic number). */
  43 struct btsnoop_hdr {
  44         guint32 version;        /* version number (should be 1) */
  45         guint32 datalink;       /* datalink type */
  46 };
  47
  48 /* "btsnoop" record header. */
  49 struct btsnooprec_hdr {
  50         guint32 orig_len;       /* actual length of packet */
  51         guint32 incl_len;       /* number of octets captured in file */
  52         guint32 flags;          /* packet flags */
  53         guint32 cum_drops;      /* cumulative number of dropped packets */
  54         gint64  ts_usec;        /* timestamp microseconds */
  55 };
  56
  57 /* H1 is unframed data with the packet type encoded in the flags field of capture header */
  58 /* It can be used for any datalink by placing logging above the datalink layer of HCI */
  59 #define KHciLoggerDatalinkTypeH1                1001
  60 /* H4 is the serial HCI with packet type encoded in the first byte of each packet */
  61 #define KHciLoggerDatalinkTypeH4                1002
  62 /* CSR's PPP derived bluecore serial protocol - in practice we log in H1 format after deframing */
  63 #define KHciLoggerDatalinkTypeBCSP              1003
  64 /* H5 is the official three wire serial protocol derived from BCSP*/
  65 #define KHciLoggerDatalinkTypeH5                1004
  66
  67 #define KHciLoggerHostToController              0
  68 #define KHciLoggerControllerToHost              0x00000001
  69 #define KHciLoggerACLDataFrame                  0
  70 #define KHciLoggerCommandOrEvent                0x00000002
  71
  72 static const gint64 KUnixTimeBase = G_GINT64_CONSTANT(0x00dcddb30f2f8000); /* offset from symbian - unix time */
  73
  74 static gboolean btsnoop_read(wtap *wth, int *err, gchar **err_info,
  75     gint64 *data_offset);
  76 static gboolean btsnoop_seek_read(wtap *wth, gint64 seek_off,
  77     struct wtap_pkthdr *phdr, Buffer *buf, int length,
  78     int *err, gchar **err_info);
  79 static gboolean btsnoop_read_record(wtap *wth, FILE_T fh,
  80     struct wtap_pkthdr *phdr, Buffer *buf, int *err, gchar **err_info);
  81
  82 int btsnoop_open(wtap *wth, int *err, gchar **err_info)
  83 {
  84         int bytes_read;
  85         char magic[sizeof btsnoop_magic];
  86         struct btsnoop_hdr hdr;
  87
  88         int file_encap=WTAP_ENCAP_UNKNOWN;
  89
  90         /* Read in the string that should be at the start of a "btsnoop" file */
  91         errno = WTAP_ERR_CANT_READ;
  92         bytes_read = file_read(magic, sizeof magic, wth->fh);
  93         if (bytes_read != sizeof magic) {
  94                 *err = file_error(wth->fh, err_info);
  95                 if (*err != 0 && *err != WTAP_ERR_SHORT_READ)
  96                         return -1;
  97                 return 0;
  98         }
  99
 100         if (memcmp(magic, btsnoop_magic, sizeof btsnoop_magic) != 0) {
 101                 return 0;
 102         }
 103
 104         /* Read the rest of the header. */
 105         errno = WTAP_ERR_CANT_READ;
 106         bytes_read = file_read(&hdr, sizeof hdr, wth->fh);
 107         if (bytes_read != sizeof hdr) {
 108                 *err = file_error(wth->fh, err_info);
 109                 if (*err == 0)
 110                         *err = WTAP_ERR_SHORT_READ;
 111                 return -1;
 112         }
 113
 114         /*
 115          * Make sure it's a version we support.
 116          */
 117         hdr.version = g_ntohl(hdr.version);
 118         if (hdr.version != 1) {
 119                 *err = WTAP_ERR_UNSUPPORTED;
 120                 *err_info = g_strdup_printf("btsnoop: version %u unsupported", hdr.version);
 121                 return -1;
 122         }
 123
 124         hdr.datalink = g_ntohl(hdr.datalink);
 125         switch (hdr.datalink) {
 126         case KHciLoggerDatalinkTypeH1:
 127                 file_encap=WTAP_ENCAP_BLUETOOTH_HCI;
 128                 break;
 129         case KHciLoggerDatalinkTypeBCSP:
 130                 *err = WTAP_ERR_UNSUPPORTED;
 131                 *err_info = g_strdup_printf("btsnoop: BCSP capture logs unsupported");
 132                 return -1;
 133         case KHciLoggerDatalinkTypeH5:
 134                 *err = WTAP_ERR_UNSUPPORTED;
 135                 *err_info = g_strdup_printf("btsnoop: H5 capture logs unsupported");
 136                 return -1;
 137         case KHciLoggerDatalinkTypeH4:
 138                 file_encap=WTAP_ENCAP_BLUETOOTH_H4_WITH_PHDR;
 139                 break;
 140         default:
 141                 *err = WTAP_ERR_UNSUPPORTED;
 142                 *err_info = g_strdup_printf("btsnoop: datalink type %u unknown or unsupported", hdr.datalink);
 143                 return -1;
 144         }
 145
 146         wth->subtype_read = btsnoop_read;
 147         wth->subtype_seek_read = btsnoop_seek_read;
 148         wth->file_encap = file_encap;
 149         wth->snapshot_length = 0;       /* not available in header */
 150         wth->tsprecision = WTAP_FILE_TSPREC_USEC;
 151         wth->file_type_subtype = WTAP_FILE_TYPE_SUBTYPE_BTSNOOP;
 152         return 1;
 153 }
 154
 155 static gboolean btsnoop_read(wtap *wth, int *err, gchar **err_info,
 156     gint64 *data_offset)
 157 {
 158         *data_offset = file_tell(wth->fh);
 159
 160         return btsnoop_read_record(wth, wth->fh, &wth->phdr, wth->frame_buffer,
 161             err, err_info);
 162 }
 163
 164 static gboolean btsnoop_seek_read(wtap *wth, gint64 seek_off,
 165     struct wtap_pkthdr *phdr, Buffer *buf, int length _U_,
 166     int *err, gchar **err_info)
 167 {
 168         if (file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1)
 169                 return FALSE;
 170
 171         return btsnoop_read_record(wth, wth->random_fh, phdr, buf, err, err_info);
 172 }
 173
 174 static gboolean btsnoop_read_record(wtap *wth, FILE_T fh,
 175     struct wtap_pkthdr *phdr, Buffer *buf, int *err, gchar **err_info)
 176 {
 177         int     bytes_read;
 178         struct btsnooprec_hdr hdr;
 179         guint32 packet_size;
 180         guint32 flags;
 181         guint32 orig_size;
 182         gint64 ts;
 183
 184         /* Read record header. */
 185
 186         errno = WTAP_ERR_CANT_READ;
 187         bytes_read = file_read(&hdr, sizeof hdr, fh);
 188         if (bytes_read != sizeof hdr) {
 189                 *err = file_error(fh, err_info);
 190                 if (*err == 0 && bytes_read != 0)
 191                         *err = WTAP_ERR_SHORT_READ;
 192                 return FALSE;
 193         }
 194
 195         packet_size = g_ntohl(hdr.incl_len);
 196         orig_size = g_ntohl(hdr.orig_len);
 197         flags = g_ntohl(hdr.flags);
 198         if (packet_size > WTAP_MAX_PACKET_SIZE) {
 199                 /*
 200                  * Probably a corrupt capture file; don't blow up trying
 201                  * to allocate space for an immensely-large packet.
 202                  */
 203                 *err = WTAP_ERR_BAD_FILE;
 204                 *err_info = g_strdup_printf("btsnoop: File has %u-byte packet, bigger than maximum of %u",
 205                     packet_size, WTAP_MAX_PACKET_SIZE);
 206                 return FALSE;
 207         }
 208
 209         ts = GINT64_FROM_BE(hdr.ts_usec);
 210         ts -= KUnixTimeBase;
 211
 212         phdr->presence_flags = WTAP_HAS_TS|WTAP_HAS_CAP_LEN;
 213         phdr->ts.secs = (guint)(ts / 1000000);
 214         phdr->ts.nsecs = (guint)((ts % 1000000) * 1000);
 215         phdr->caplen = packet_size;
 216         phdr->len = orig_size;
 217         if(wth->file_encap == WTAP_ENCAP_BLUETOOTH_H4_WITH_PHDR)
 218         {
 219                 phdr->pseudo_header.p2p.sent = (flags & KHciLoggerControllerToHost) ? FALSE : TRUE;
 220         }
 221         else if(wth->file_encap == WTAP_ENCAP_BLUETOOTH_HCI)
 222         {
 223                 phdr->pseudo_header.bthci.sent = (flags & KHciLoggerControllerToHost) ? FALSE : TRUE;
 224                 if(flags & KHciLoggerCommandOrEvent)
 225                 {
 226                         if(phdr->pseudo_header.bthci.sent)
 227                         {
 228                                 phdr->pseudo_header.bthci.channel = BTHCI_CHANNEL_COMMAND;
 229                         }
 230                         else
 231                         {
 232                                 phdr->pseudo_header.bthci.channel = BTHCI_CHANNEL_EVENT;
 233                         }
 234                 }
 235                 else
 236                 {
 237                         phdr->pseudo_header.bthci.channel = BTHCI_CHANNEL_ACL;
 238                 }
 239         }
 240
 241
 242         /* Read packet data. */
 243         return wtap_read_packet_bytes(fh, buf, phdr->caplen, err, err_info);
 244 }
 245
 246 /* Returns 0 if we could write the specified encapsulation type,
 247    an error indication otherwise. */
 248 int btsnoop_dump_can_write_encap(int encap)
 249 {
 250     /* Per-packet encapsulations aren't supported. */
 251     if (encap == WTAP_ENCAP_PER_PACKET)
 252         return WTAP_ERR_ENCAP_PER_PACKET_UNSUPPORTED;
 253
 254     /* XXX - for now we only support WTAP_ENCAP_BLUETOOTH_H4_WITH_PHDR */
 255     if (encap != WTAP_ENCAP_BLUETOOTH_H4_WITH_PHDR)
 256         return WTAP_ERR_UNSUPPORTED_ENCAP;
 257
 258     return 0;
 259 }
 260
 261 struct hci_flags_mapping
 262 {
 263     guint8 hci_type;
 264     guint8 sent;
 265     guint8 flags;
 266 };
 267
 268 static const struct hci_flags_mapping hci_flags[] =
 269 {
 270     { 0x02, TRUE,   KHciLoggerHostToController|KHciLoggerACLDataFrame   }, /* HCI_H4_TYPE_ACL */
 271     { 0x02, FALSE,  KHciLoggerControllerToHost|KHciLoggerACLDataFrame   }, /* HCI_H4_TYPE_ACL */
 272     { 0x01, TRUE,   KHciLoggerHostToController|KHciLoggerCommandOrEvent }, /* HCI_H4_TYPE_CMD */
 273     { 0x04, FALSE,  KHciLoggerControllerToHost|KHciLoggerCommandOrEvent }, /* HCI_H4_TYPE_EVT */
 274 };
 275
 276 static guint8 btsnoop_lookup_flags(guint8 hci_type, gboolean sent, guint8 *flags)
 277 {
 278     guint8 i;
 279
 280     for (i=0; i < G_N_ELEMENTS(hci_flags); ++i)
 281     {
 282         if (hci_flags[i].hci_type == hci_type &&
 283             hci_flags[i].sent == sent)
 284         {
 285             *flags = hci_flags[i].flags;
 286             return TRUE;
 287         }
 288     }
 289     return FALSE;
 290 }
 291
 292 static gboolean btsnoop_dump_partial_rec_hdr(wtap_dumper *wdh _U_,
 293     const struct wtap_pkthdr *phdr,
 294     const union wtap_pseudo_header *pseudo_header,
 295     const guint8 *pd, int *err,
 296     struct btsnooprec_hdr *rec_hdr)
 297 {
 298     gint64 ts_usec;
 299     gint64 nsecs;
 300     guint8 flags = 0;
 301
 302     if (!btsnoop_lookup_flags(*pd, pseudo_header->p2p.sent, &flags)) {
 303         *err = WTAP_ERR_UNSUPPORTED;
 304         return FALSE;
 305     }
 306
 307     nsecs = phdr->ts.nsecs;
 308     ts_usec  = ((gint64) phdr->ts.secs * 1000000) + (nsecs / 1000);
 309     ts_usec += KUnixTimeBase;
 310
 311     rec_hdr->flags = GUINT32_TO_BE(flags);
 312     rec_hdr->cum_drops = GUINT32_TO_BE(0);
 313     rec_hdr->ts_usec = GINT64_TO_BE(ts_usec);
 314
 315     return TRUE;
 316 }
 317
 318 /* FIXME: How do we support multiple backends?*/
 319 static gboolean btsnoop_dump_h1(wtap_dumper *wdh,
 320     const struct wtap_pkthdr *phdr,
 321     const guint8 *pd, int *err)
 322 {
 323     const union wtap_pseudo_header *pseudo_header = &phdr->pseudo_header;
 324     struct btsnooprec_hdr rec_hdr;
 325
 326     if (!btsnoop_dump_partial_rec_hdr(wdh, phdr, pseudo_header, pd, err, &rec_hdr))
 327         return FALSE;
 328
 329     rec_hdr.incl_len = GUINT32_TO_BE(phdr->caplen-1);
 330     rec_hdr.orig_len = GUINT32_TO_BE(phdr->len-1);
 331
 332     if (!wtap_dump_file_write(wdh, &rec_hdr, sizeof rec_hdr, err))
 333         return FALSE;
 334
 335     wdh->bytes_dumped += sizeof rec_hdr;
 336
 337     /* Skip HCI packet type */
 338     ++pd;
 339
 340     if (!wtap_dump_file_write(wdh, pd, phdr->caplen-1, err))
 341         return FALSE;
 342
 343     wdh->bytes_dumped += phdr->caplen-1;
 344
 345     return TRUE;
 346 }
 347
 348 static gboolean btsnoop_dump_h4(wtap_dumper *wdh,
 349     const struct wtap_pkthdr *phdr,
 350     const guint8 *pd, int *err)
 351 {
 352     const union wtap_pseudo_header *pseudo_header = &phdr->pseudo_header;
 353     struct btsnooprec_hdr rec_hdr;
 354
 355     if (!btsnoop_dump_partial_rec_hdr(wdh, phdr, pseudo_header, pd, err, &rec_hdr))
 356         return FALSE;
 357
 358     rec_hdr.incl_len = GUINT32_TO_BE(phdr->caplen);
 359     rec_hdr.orig_len = GUINT32_TO_BE(phdr->len);
 360
 361     if (!wtap_dump_file_write(wdh, &rec_hdr, sizeof rec_hdr, err))
 362         return FALSE;
 363
 364     wdh->bytes_dumped += sizeof rec_hdr;
 365
 366     if (!wtap_dump_file_write(wdh, pd, phdr->caplen, err))
 367         return FALSE;
 368
 369     wdh->bytes_dumped += phdr->caplen;
 370
 371     return TRUE;
 372 }
 373
 374 /* FIXME: How do we support multiple backends?*/
 375 gboolean btsnoop_dump_open_h1(wtap_dumper *wdh, int *err)
 376 {
 377     struct btsnoop_hdr file_hdr;
 378
 379     /* This is a libpcap file */
 380     wdh->subtype_write = btsnoop_dump_h1;
 381     wdh->subtype_close = NULL;
 382
 383     /* Write the file header. */
 384     switch (wdh->file_type_subtype) {
 385
 386     case WTAP_FILE_TYPE_SUBTYPE_BTSNOOP:
 387         wdh->tsprecision = WTAP_FILE_TSPREC_USEC;
 388         break;
 389
 390     default:
 391         /* We should never get here - our open routine
 392            should only get called for the types above. */
 393         *err = WTAP_ERR_UNSUPPORTED_FILE_TYPE;
 394         return FALSE;
 395     }
 396
 397     if (!wtap_dump_file_write(wdh, btsnoop_magic, sizeof btsnoop_magic, err))
 398         return FALSE;
 399
 400     wdh->bytes_dumped += sizeof btsnoop_magic;
 401
 402     /* current "btsnoop" format is 1 */
 403     file_hdr.version  = GUINT32_TO_BE(1);
 404     /* HCI type encoded in first byte */
 405     file_hdr.datalink = GUINT32_TO_BE(KHciLoggerDatalinkTypeH1);
 406
 407     if (!wtap_dump_file_write(wdh, &file_hdr, sizeof file_hdr, err))
 408         return FALSE;
 409
 410     wdh->bytes_dumped += sizeof file_hdr;
 411
 412     return TRUE;
 413 }
 414
 415 /* Returns TRUE on success, FALSE on failure; sets "*err" to an error code on
 416    failure */
 417 gboolean btsnoop_dump_open_h4(wtap_dumper *wdh, int *err)
 418 {
 419     struct btsnoop_hdr file_hdr;
 420
 421     /* This is a libpcap file */
 422     wdh->subtype_write = btsnoop_dump_h4;
 423     wdh->subtype_close = NULL;
 424
 425     /* Write the file header. */
 426     switch (wdh->file_type_subtype) {
 427
 428     case WTAP_FILE_TYPE_SUBTYPE_BTSNOOP:
 429         wdh->tsprecision = WTAP_FILE_TSPREC_USEC;
 430         break;
 431
 432     default:
 433         /* We should never get here - our open routine
 434            should only get called for the types above. */
 435         *err = WTAP_ERR_UNSUPPORTED_FILE_TYPE;
 436         return FALSE;
 437     }
 438
 439     if (!wtap_dump_file_write(wdh, btsnoop_magic, sizeof btsnoop_magic, err))
 440         return FALSE;
 441
 442     wdh->bytes_dumped += sizeof btsnoop_magic;
 443
 444     /* current "btsnoop" format is 1 */
 445     file_hdr.version  = GUINT32_TO_BE(1);
 446     /* HCI type encoded in first byte */
 447     file_hdr.datalink = GUINT32_TO_BE(KHciLoggerDatalinkTypeH4);
 448
 449     if (!wtap_dump_file_write(wdh, &file_hdr, sizeof file_hdr, err))
 450         return FALSE;
 451
 452     wdh->bytes_dumped += sizeof file_hdr;
 453
 454     return TRUE;
 455 }