wiretap/busmaster.c

   1 /* busmaster.c
   2  *
   3  * Wiretap Library
   4  * Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
   5  *
   6  * Support for Busmaster log file format
   7  * Copyright (c) 2019 by Maksim Salau <maksim.salau@gmail.com>
   8  *
   9  * SPDX-License-Identifier: GPL-2.0-or-later
  10  */
  11
  12 #include "config.h"
  13 #include "busmaster.h"
  14
  15 #include <wtap-int.h>
  16 #include <file_wrappers.h>
  17 #include <epan/dissectors/packet-socketcan.h>
  18 #include <wsutil/exported_pdu_tlvs.h>
  19 #include "busmaster_priv.h"
  20 #include <inttypes.h>
  21 #include <string.h>
  22 #include <errno.h>
  23
  24 static void
  25 busmaster_close(wtap *wth);
  26
  27 static bool
  28 busmaster_read(wtap   *wth, wtap_rec *rec, Buffer *buf,
  29                int    *err, char **err_info,
  30                int64_t *data_offset);
  31
  32 static bool
  33 busmaster_seek_read(wtap     *wth, int64_t seek_off,
  34                     wtap_rec *rec, Buffer *buf,
  35                     int      *err, char **err_info);
  36
  37 static int busmaster_file_type_subtype = -1;
  38
  39 void register_busmaster(void);
  40
  41 /*
  42  * See
  43  *
  44  *    https://rbei-etas.github.io/busmaster/
  45  *
  46  * for the BUSMASTER software.
  47  */
  48
  49 static bool
  50 busmaster_gen_packet(wtap_rec               *rec, Buffer *buf,
  51                      const busmaster_priv_t *priv_entry, const msg_t *msg,
  52                      int                    *err, char **err_info)
  53 {
  54     time_t secs     = 0;
  55     uint32_t nsecs  = 0;
  56     bool has_ts = false;
  57     bool is_fd  = (msg->type == MSG_TYPE_STD_FD)
  58         || (msg->type == MSG_TYPE_EXT_FD);
  59     bool is_eff = (msg->type == MSG_TYPE_EXT)
  60         || (msg->type == MSG_TYPE_EXT_RTR)
  61         || (msg->type == MSG_TYPE_EXT_FD);
  62     bool is_rtr = (msg->type == MSG_TYPE_STD_RTR)
  63         || (msg->type == MSG_TYPE_EXT_RTR);
  64     bool is_err = (msg->type == MSG_TYPE_ERR);
  65
  66     if (!priv_entry)
  67     {
  68         *err      = WTAP_ERR_BAD_FILE;
  69         *err_info = g_strdup("Header is missing");
  70         return false;
  71     }
  72
  73     ws_buffer_clean(buf);
  74
  75     if (is_fd)
  76     {
  77         canfd_frame_t canfd_frame = {0};
  78
  79         canfd_frame.can_id = g_htonl((msg->id & (is_eff ? CAN_EFF_MASK : CAN_SFF_MASK)) |
  80             (is_eff ? CAN_EFF_FLAG : 0) |
  81             (is_err ? CAN_ERR_FLAG : 0));
  82         canfd_frame.flags  = CANFD_FDF;
  83         canfd_frame.len    = msg->data.length;
  84
  85         memcpy(canfd_frame.data,
  86                msg->data.data,
  87                MIN(msg->data.length, sizeof(canfd_frame.data)));
  88
  89         ws_buffer_append(buf,
  90                (uint8_t *)&canfd_frame,
  91                sizeof(canfd_frame));
  92     }
  93     else
  94     {
  95         can_frame_t can_frame = {0};
  96
  97         can_frame.can_id  = g_htonl((msg->id & (is_eff ? CAN_EFF_MASK : CAN_SFF_MASK)) |
  98             (is_rtr ? CAN_RTR_FLAG : 0) |
  99             (is_eff ? CAN_EFF_FLAG : 0) |
 100             (is_err ? CAN_ERR_FLAG : 0));
 101         can_frame.can_dlc = msg->data.length;
 102
 103         memcpy(can_frame.data,
 104                msg->data.data,
 105                MIN(msg->data.length, sizeof(can_frame.data)));
 106
 107         ws_buffer_append(buf,
 108                (uint8_t *)&can_frame,
 109                sizeof(can_frame));
 110     }
 111
 112     if (priv_entry->time_mode == TIME_MODE_SYSTEM)
 113     {
 114         struct tm tm;
 115
 116         tm.tm_year  = priv_entry->start_date.year - 1900;
 117         tm.tm_mon   = priv_entry->start_date.month - 1;
 118         tm.tm_mday  = priv_entry->start_date.day;
 119         tm.tm_hour  = msg->timestamp.hours;
 120         tm.tm_min   = msg->timestamp.minutes;
 121         tm.tm_sec   = msg->timestamp.seconds;
 122         tm.tm_isdst = -1;
 123
 124         secs   = mktime(&tm);
 125         nsecs  = msg->timestamp.micros * 1000u;
 126         has_ts = true;
 127     }
 128     else if (priv_entry->time_mode == TIME_MODE_ABSOLUTE)
 129     {
 130         struct tm tm;
 131         uint32_t  micros;
 132
 133         tm.tm_year  = priv_entry->start_date.year - 1900;
 134         tm.tm_mon   = priv_entry->start_date.month - 1;
 135         tm.tm_mday  = priv_entry->start_date.day;
 136         tm.tm_hour  = priv_entry->start_time.hours;
 137         tm.tm_min   = priv_entry->start_time.minutes;
 138         tm.tm_sec   = priv_entry->start_time.seconds;
 139         tm.tm_isdst = -1;
 140
 141         secs = mktime(&tm);
 142
 143         secs += msg->timestamp.hours * 3600;
 144         secs += msg->timestamp.minutes * 60;
 145         secs += msg->timestamp.seconds;
 146
 147         micros = priv_entry->start_time.micros + msg->timestamp.micros;
 148         if (micros >= 1000000u)
 149         {
 150             micros -= 1000000u;
 151             secs   += 1;
 152         }
 153
 154         nsecs  = micros * 1000u;
 155         has_ts = true;
 156     }
 157
 158     rec->rec_type       = REC_TYPE_PACKET;
 159     rec->block          = wtap_block_create(WTAP_BLOCK_PACKET);
 160     rec->presence_flags = has_ts ? WTAP_HAS_TS : 0;
 161     rec->ts.secs        = secs;
 162     rec->ts.nsecs       = nsecs;
 163
 164     rec->rec_header.packet_header.caplen = (uint32_t)ws_buffer_length(buf);
 165     rec->rec_header.packet_header.len    = (uint32_t)ws_buffer_length(buf);
 166
 167     return true;
 168 }
 169
 170 static log_entry_type_t
 171 busmaster_parse(FILE_T fh, busmaster_state_t *state, int *err, char **err_info)
 172 {
 173     bool ok;
 174     int64_t  seek_off;
 175
 176     busmaster_debug_printf("%s: Running busmaster file decoder\n", G_STRFUNC);
 177
 178     state->fh = fh;
 179
 180     do
 181     {
 182         if (file_eof(fh))
 183             return LOG_ENTRY_EOF;
 184
 185         seek_off               = file_tell(fh);
 186         busmaster_debug_printf("%s: Starting parser at offset %" PRIi64 "\n",
 187                                G_STRFUNC, seek_off);
 188         state->file_bytes_read = 0;
 189         ok                     = run_busmaster_parser(state, err, err_info);
 190
 191         /* Rewind the file to the offset we have finished parsing */
 192         busmaster_debug_printf("%s: Rewinding to offset %" PRIi64 "\n",
 193                                G_STRFUNC, seek_off + state->file_bytes_read);
 194         if (file_seek(fh, seek_off + state->file_bytes_read, SEEK_SET, err) == -1)
 195         {
 196             g_free(*err_info);
 197             *err      = errno;
 198             *err_info = g_strdup(g_strerror(errno));
 199             return LOG_ENTRY_ERROR;
 200         }
 201     }
 202     while (ok && state->entry_type == LOG_ENTRY_NONE);
 203
 204     if (!ok)
 205         return LOG_ENTRY_ERROR;
 206
 207     busmaster_debug_printf("%s: Success\n", G_STRFUNC);
 208
 209     return state->entry_type;
 210 }
 211
 212 wtap_open_return_val
 213 busmaster_open(wtap *wth, int *err, char **err_info)
 214 {
 215     busmaster_state_t state = {0};
 216     log_entry_type_t  entry;
 217
 218     busmaster_debug_printf("%s: Trying to open with busmaster log reader\n",
 219                            G_STRFUNC);
 220
 221     /* Rewind to the beginning */
 222     if (file_seek(wth->fh, 0, SEEK_SET, err) == -1)
 223         return WTAP_OPEN_ERROR;
 224
 225     entry = busmaster_parse(wth->fh, &state, err, err_info);
 226
 227     g_free(*err_info);
 228     *err_info = NULL;
 229     *err      = 0;
 230
 231     if (entry != LOG_ENTRY_HEADER)
 232         return WTAP_OPEN_NOT_MINE;
 233
 234     /* Rewind to the beginning, so busmaster_read may read from the very beginning */
 235     if (file_seek(wth->fh, 0, SEEK_SET, err) == -1)
 236         return WTAP_OPEN_ERROR;
 237
 238     busmaster_debug_printf("%s: That's a busmaster log\n", G_STRFUNC);
 239
 240     wth->priv              = NULL;
 241     wth->subtype_close     = busmaster_close;
 242     wth->subtype_read      = busmaster_read;
 243     wth->subtype_seek_read = busmaster_seek_read;
 244     wth->file_type_subtype = busmaster_file_type_subtype;
 245     wth->file_encap        = WTAP_ENCAP_SOCKETCAN;
 246     wth->file_tsprec       = WTAP_TSPREC_USEC;
 247
 248     return WTAP_OPEN_MINE;
 249 }
 250
 251 static void
 252 busmaster_close(wtap *wth)
 253 {
 254     busmaster_debug_printf("%s\n", G_STRFUNC);
 255
 256     g_slist_free_full((GSList *)wth->priv, g_free);
 257     wth->priv = NULL;
 258 }
 259
 260 static busmaster_priv_t *
 261 busmaster_find_priv_entry(void *priv, int64_t offset)
 262 {
 263     GSList *list;
 264
 265     for (list = (GSList *)priv; list; list = g_slist_next(list))
 266     {
 267         busmaster_priv_t *entry = (busmaster_priv_t *)list->data;
 268
 269         if (((entry->file_end_offset == -1)
 270              && (g_slist_next(list) == NULL))
 271             || ((offset >= entry->file_start_offset)
 272                 && (offset <= entry->file_end_offset)))
 273         {
 274             return entry;
 275         }
 276     }
 277
 278     return NULL;
 279 }
 280
 281 static bool
 282 busmaster_read(wtap   *wth, wtap_rec *rec, Buffer *buf, int *err, char **err_info,
 283                int64_t *data_offset)
 284 {
 285     log_entry_type_t   entry;
 286     busmaster_state_t  state;
 287     busmaster_priv_t  *priv_entry;
 288     bool               is_msg = false;
 289     bool               is_ok = true;
 290
 291     while (!is_msg && is_ok)
 292     {
 293         busmaster_debug_printf("%s: offset = %" PRIi64 "\n",
 294                                G_STRFUNC, file_tell(wth->fh));
 295
 296         if (file_eof(wth->fh))
 297         {
 298             busmaster_debug_printf("%s: End of file detected, nothing to do here\n",
 299                                    G_STRFUNC);
 300             *err      = 0;
 301             *err_info = NULL;
 302             return false;
 303         }
 304
 305         *data_offset = file_tell(wth->fh);
 306         priv_entry   = busmaster_find_priv_entry(wth->priv, *data_offset);
 307
 308         memset(&state, 0, sizeof(state));
 309         if (priv_entry)
 310             state.header = *priv_entry;
 311         entry = busmaster_parse(wth->fh, &state, err, err_info);
 312
 313         busmaster_debug_printf("%s: analyzing output\n", G_STRFUNC);
 314         switch (entry)
 315         {
 316         case LOG_ENTRY_EMPTY:
 317             break;
 318         case LOG_ENTRY_FOOTER_AND_HEADER:
 319         case LOG_ENTRY_FOOTER:
 320             priv_entry = (busmaster_priv_t *)g_slist_last((GSList *)wth->priv)->data;
 321             if (!priv_entry)
 322             {
 323                 *err      = WTAP_ERR_BAD_FILE;
 324                 *err_info = g_strdup("Header is missing");
 325                 return false;
 326             }
 327             priv_entry->file_end_offset  = *data_offset;
 328             if (entry == LOG_ENTRY_FOOTER)
 329                 break;
 330             /* fall-through */
 331         case LOG_ENTRY_HEADER:
 332             if (state.header.protocol != PROTOCOL_CAN &&
 333                 state.header.protocol != PROTOCOL_J1939)
 334             {
 335                 *err      = WTAP_ERR_UNSUPPORTED;
 336                 *err_info = g_strdup("Unsupported protocol type");
 337                 return false;
 338             }
 339
 340             if (wth->priv)
 341             {
 342                 /* Check that the previous section has a footer */
 343                 priv_entry = (busmaster_priv_t *)g_slist_last((GSList *)wth->priv)->data;
 344
 345                 if (priv_entry && priv_entry->file_end_offset == -1)
 346                 {
 347                     *err      = WTAP_ERR_BAD_FILE;
 348                     *err_info = g_strdup("Footer is missing");
 349                     return false;
 350                 }
 351             }
 352
 353             /* Start a new section */
 354             priv_entry = g_new(busmaster_priv_t, 1);
 355
 356             priv_entry[0]                 = state.header;
 357             priv_entry->file_start_offset = file_tell(wth->fh);
 358             priv_entry->file_end_offset   = -1;
 359
 360             wth->priv = g_slist_append((GSList *)wth->priv, priv_entry);
 361             break;
 362         case LOG_ENTRY_MSG:
 363             is_msg     = true;
 364             priv_entry = busmaster_find_priv_entry(wth->priv, *data_offset);
 365             is_ok      = busmaster_gen_packet(rec, buf, priv_entry, &state.msg, err, err_info);
 366             break;
 367         case LOG_ENTRY_EOF:
 368         case LOG_ENTRY_ERROR:
 369         case LOG_ENTRY_NONE:
 370         default:
 371             is_ok = false;
 372             break;
 373         }
 374     }
 375
 376     busmaster_debug_printf("%s: stopped at offset %" PRIi64 " with entry %d\n",
 377                            G_STRFUNC, file_tell(wth->fh), entry);
 378
 379     return is_ok;
 380 }
 381
 382 static bool
 383 busmaster_seek_read(wtap   *wth, int64_t seek_off, wtap_rec *rec,
 384                     Buffer *buf, int *err, char **err_info)
 385 {
 386     busmaster_priv_t  *priv_entry;
 387     busmaster_state_t  state = {0};
 388     log_entry_type_t   entry;
 389
 390     busmaster_debug_printf("%s: offset = %" PRIi64 "\n", G_STRFUNC, seek_off);
 391
 392     priv_entry = busmaster_find_priv_entry(wth->priv, seek_off);
 393     if (!priv_entry)
 394     {
 395         busmaster_debug_printf("%s: analyzing output\n", G_STRFUNC);
 396         *err = WTAP_ERR_BAD_FILE;
 397         *err_info = g_strdup("Malformed header");
 398         return false;
 399     }
 400
 401     if (file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1)
 402         return false;
 403
 404     state.header = *priv_entry;
 405     entry = busmaster_parse(wth->random_fh, &state, err, err_info);
 406
 407     busmaster_debug_printf("%s: analyzing output\n", G_STRFUNC);
 408
 409     if (entry == LOG_ENTRY_ERROR || entry == LOG_ENTRY_NONE)
 410         return false;
 411
 412     if (entry != LOG_ENTRY_MSG)
 413     {
 414         *err = WTAP_ERR_BAD_FILE;
 415         *err_info = g_strdup("Failed to read a frame");
 416         return false;
 417     }
 418
 419     return busmaster_gen_packet(rec, buf, priv_entry, &state.msg, err, err_info);
 420 }
 421
 422 static const struct supported_block_type busmaster_blocks_supported[] = {
 423     /*
 424      * We support packet blocks, with no comments or other options.
 425      */
 426     { WTAP_BLOCK_PACKET, MULTIPLE_BLOCKS_SUPPORTED, NO_OPTIONS_SUPPORTED }
 427 };
 428
 429 static const struct file_type_subtype_info busmaster_info = {
 430     "BUSMASTER log file", "busmaster", "log", NULL,
 431     false, BLOCKS_SUPPORTED(busmaster_blocks_supported),
 432     NULL, NULL, NULL
 433 };
 434
 435 void register_busmaster(void)
 436 {
 437     busmaster_file_type_subtype = wtap_register_file_type_subtype(&busmaster_info);
 438 }
 439
 440 /*
 441  * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 442  *
 443  * Local variables:
 444  * c-basic-offset: 4
 445  * tab-width: 8
 446  * indent-tabs-mode: nil
 447  * End:
 448  *
 449  * vi: set shiftwidth=4 tabstop=8 expandtab:
 450  * :indentSize=4:tabSize=8:noTabs=true:
 451  */