wiretap/commview.c

   1 /* commview.c
   2  * Routines for opening CommView file format packet captures
   3  * Copyright 2007, Stephen Fisher (see AUTHORS file)
   4  *
   5  * $Id$
   6  *
   7  * Wireshark - Network traffic analyzer
   8  * By Gerald Combs <gerald@wireshark.org>
   9  * Copyright 1998 Gerald Combs
  10  *
  11  * Based on csids.c and nettl.c
  12  *
  13  * This program is free software; you can redistribute it and/or
  14  * modify it under the terms of the GNU General Public License
  15  * as published by the Free Software Foundation; either version 2
  16  * of the License, or (at your option) any later version.
  17  *
  18  * This program is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with this program; if not, write to the Free Software
  25  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
  26  * USA.
  27  */
  28
  29 /* A brief description of this file format is available at:
  30  *    http://www.tamos.com/htmlhelp/commview/logformat.htm
  31  */
  32
  33 #ifdef HAVE_CONFIG_H
  34 #include "config.h"
  35 #endif
  36
  37 #include <glib.h>
  38 #include <stdio.h>
  39 #include <stdlib.h>
  40 #include <errno.h>
  41 #include <string.h>
  42
  43 #include "wtap.h"
  44 #include "wtap-int.h"
  45 #include "buffer.h"
  46 #include "file_wrappers.h"
  47 #include "commview.h"
  48
  49 typedef struct commview_header {
  50         guint16         data_len;
  51         guint16         source_data_len;
  52         guint8          version;
  53         guint16         year;
  54         guint8          month;
  55         guint8          day;
  56         guint8          hours;
  57         guint8          minutes;
  58         guint8          seconds;
  59         guint32         usecs;
  60         guint8          flags;          /* Bit-field positions defined below */
  61         guint8          signal_level_percent;
  62         guint8          rate;
  63         guint8          band;
  64         guint8          channel;
  65         guint8          direction;      /* Or for WiFi, high order byte of
  66                                          * packet rate. */
  67         guint8          signal_level_dbm;
  68         guint8          noise_level;    /* In dBm (WiFi only) */
  69 } commview_header_t;
  70
  71 #define COMMVIEW_HEADER_SIZE 24
  72
  73 /* Bit-field positions for various fields in the flags variable of the header */
  74 #define FLAGS_MEDIUM            0x0F
  75 #define FLAGS_DECRYPTED         0x10
  76 #define FLAGS_BROKEN            0x20
  77 #define FLAGS_COMPRESSED        0x40
  78 #define FLAGS_RESERVED          0x80
  79
  80 /* Capture mediums as defined by the commview file format */
  81 #define MEDIUM_ETHERNET         0
  82 #define MEDIUM_WIFI             1
  83 #define MEDIUM_TOKEN_RING       2
  84
  85 static gboolean commview_read(wtap *wth, int *err, gchar **err_info,
  86                               gint64 *data_offset);
  87 static gboolean commview_seek_read(wtap *wth, gint64 seek_off,
  88                                    union wtap_pseudo_header *pseudo_header,
  89                                    guchar *pd, int length, int *err,
  90                                    gchar **err_info);
  91 static gboolean commview_read_header(commview_header_t *cv_hdr, FILE_T fh,
  92                                      int *err, gchar **err_info);
  93 static gboolean commview_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
  94                               const union wtap_pseudo_header *pseudo_header,
  95                               const guchar *pd, int *err);
  96
  97 int commview_open(wtap *wth, int *err, gchar **err_info)
  98 {
  99         commview_header_t cv_hdr;
 100
 101         if(!commview_read_header(&cv_hdr, wth->fh, err, err_info))
 102                 return -1;
 103
 104         /* If any of these fields do not match what we expect, bail out. */
 105         if(cv_hdr.version != 0 ||
 106            cv_hdr.year < 1970 || cv_hdr.year >= 2038 ||
 107            cv_hdr.month < 1 || cv_hdr.month > 12 ||
 108            cv_hdr.day < 1 || cv_hdr.day > 31 ||
 109            cv_hdr.hours > 23 ||
 110            cv_hdr.minutes > 59 ||
 111            cv_hdr.seconds > 60 ||
 112            cv_hdr.signal_level_percent > 100 ||
 113            (cv_hdr.flags & FLAGS_RESERVED) != 0 ||
 114            ((cv_hdr.flags & FLAGS_MEDIUM) != MEDIUM_ETHERNET &&
 115             (cv_hdr.flags & FLAGS_MEDIUM) != MEDIUM_WIFI &&
 116             (cv_hdr.flags & FLAGS_MEDIUM) != MEDIUM_TOKEN_RING))
 117                 return 0; /* Not our kind of file */
 118
 119         /* No file header. Reset the fh to 0 so we can read the first packet */
 120         if (file_seek(wth->fh, 0, SEEK_SET, err) == -1)
 121                 return -1;
 122
 123         /* Set up the pointers to the handlers for this file type */
 124         wth->subtype_read = commview_read;
 125         wth->subtype_seek_read = commview_seek_read;
 126
 127         wth->data_offset = 0;
 128         wth->file_type = WTAP_FILE_COMMVIEW;
 129         wth->file_encap = WTAP_ENCAP_PER_PACKET;
 130         wth->tsprecision = WTAP_FILE_TSPREC_USEC;
 131
 132         return 1; /* Our kind of file */
 133 }
 134
 135 static void
 136 commview_set_pseudo_header(commview_header_t *cv_hdrp, union wtap_pseudo_header
 137                            *pseudo_header)
 138 {
 139         switch(cv_hdrp->flags & FLAGS_MEDIUM) {
 140
 141         case MEDIUM_ETHERNET :
 142                 pseudo_header->eth.fcs_len = -1; /* Unknown */
 143                 break;
 144
 145         case MEDIUM_WIFI :
 146                 pseudo_header->ieee_802_11.fcs_len = -1; /* Unknown */
 147                 pseudo_header->ieee_802_11.channel = cv_hdrp->channel;
 148                 pseudo_header->ieee_802_11.data_rate = cv_hdrp->rate;
 149                 pseudo_header->ieee_802_11.signal_level = cv_hdrp->signal_level_percent;
 150                 break;
 151
 152         default :
 153                 /* Token Ring or unknown - no pseudo-header for that */
 154                 break;
 155         }
 156 }
 157
 158 static gboolean
 159 commview_read(wtap *wth, int *err, gchar **err_info, gint64 *data_offset)
 160 {
 161         commview_header_t cv_hdr;
 162         struct tm tm;
 163         int bytes_read;
 164
 165         *data_offset = wth->data_offset;
 166
 167         if(!commview_read_header(&cv_hdr, wth->fh, err, err_info))
 168                 return FALSE;
 169
 170         wth->data_offset += COMMVIEW_HEADER_SIZE;
 171
 172         switch(cv_hdr.flags & FLAGS_MEDIUM) {
 173
 174         case MEDIUM_ETHERNET :
 175                 wth->phdr.pkt_encap = WTAP_ENCAP_ETHERNET;
 176                 break;
 177
 178         case MEDIUM_WIFI :
 179                 wth->phdr.pkt_encap = WTAP_ENCAP_IEEE_802_11_WITH_RADIO;
 180                 break;
 181
 182         case MEDIUM_TOKEN_RING :
 183                 wth->phdr.pkt_encap = WTAP_ENCAP_TOKEN_RING;
 184                 break;
 185
 186         default :
 187                 *err = WTAP_ERR_BAD_RECORD;
 188                 *err_info = g_strdup_printf("commview: unsupported encap: %u",
 189                                             cv_hdr.flags & FLAGS_MEDIUM);
 190                 return FALSE;
 191         }
 192
 193         commview_set_pseudo_header(&cv_hdr, &wth->pseudo_header);
 194
 195         buffer_assure_space(wth->frame_buffer, cv_hdr.data_len);
 196         bytes_read = file_read(buffer_start_ptr(wth->frame_buffer),
 197                                cv_hdr.data_len, wth->fh);
 198         if(bytes_read != cv_hdr.data_len) {
 199                 *err = file_error(wth->fh, err_info);
 200                 if(*err == 0)
 201                         *err = WTAP_ERR_SHORT_READ;
 202                 return FALSE;
 203         }
 204
 205         tm.tm_year = cv_hdr.year - 1900;
 206         tm.tm_mon = cv_hdr.month - 1;
 207         tm.tm_mday = cv_hdr.day;
 208         tm.tm_hour = cv_hdr.hours;
 209         tm.tm_min = cv_hdr.minutes;
 210         tm.tm_sec = cv_hdr.seconds;
 211         tm.tm_isdst = -1;
 212
 213         wth->data_offset += cv_hdr.data_len;
 214
 215         wth->phdr.len = cv_hdr.data_len;
 216         wth->phdr.caplen = cv_hdr.data_len;
 217
 218         wth->phdr.ts.secs = mktime(&tm);
 219         wth->phdr.ts.nsecs = cv_hdr.usecs * 1000;
 220
 221         return TRUE;
 222 }
 223
 224 static gboolean
 225 commview_seek_read(wtap *wth, gint64 seek_off, union wtap_pseudo_header
 226                    *pseudo_header, guchar *pd, int length, int *err,
 227                    gchar **err_info)
 228 {
 229         commview_header_t cv_hdr;
 230         int bytes_read;
 231
 232         if(file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1)
 233                 return FALSE;
 234
 235         if(!commview_read_header(&cv_hdr, wth->random_fh, err, err_info)) {
 236                 if(*err == 0)
 237                         *err = WTAP_ERR_SHORT_READ;
 238
 239                 return FALSE;
 240         }
 241
 242         if(length != cv_hdr.data_len) {
 243                 *err = WTAP_ERR_BAD_RECORD;
 244                 *err_info = g_strdup_printf("commview: record length %u doesn't match requested length %d", cv_hdr.data_len, length);
 245                 return FALSE;
 246         }
 247
 248         commview_set_pseudo_header(&cv_hdr, pseudo_header);
 249
 250         bytes_read = file_read(pd, cv_hdr.data_len, wth->random_fh);
 251         if(bytes_read != cv_hdr.data_len) {
 252                 *err = file_error(wth->random_fh, err_info);
 253                 if(*err == 0)
 254                         *err = WTAP_ERR_SHORT_READ;
 255
 256                 return FALSE;
 257         }
 258
 259         return TRUE;
 260 }
 261
 262 static gboolean
 263 commview_read_header(commview_header_t *cv_hdr, FILE_T fh, int *err,
 264     gchar **err_info)
 265 {
 266         wtap_file_read_expected_bytes(&cv_hdr->data_len, 2, fh, err, err_info);
 267         wtap_file_read_expected_bytes(&cv_hdr->source_data_len, 2, fh, err, err_info);
 268         wtap_file_read_expected_bytes(&cv_hdr->version, 1, fh, err, err_info);
 269         wtap_file_read_expected_bytes(&cv_hdr->year, 2, fh, err, err_info);
 270         wtap_file_read_expected_bytes(&cv_hdr->month, 1, fh, err, err_info);
 271         wtap_file_read_expected_bytes(&cv_hdr->day, 1, fh, err, err_info);
 272         wtap_file_read_expected_bytes(&cv_hdr->hours, 1, fh, err, err_info);
 273         wtap_file_read_expected_bytes(&cv_hdr->minutes, 1, fh, err, err_info);
 274         wtap_file_read_expected_bytes(&cv_hdr->seconds, 1, fh, err, err_info);
 275         wtap_file_read_expected_bytes(&cv_hdr->usecs, 4, fh, err, err_info);
 276         wtap_file_read_expected_bytes(&cv_hdr->flags, 1, fh, err, err_info);
 277         wtap_file_read_expected_bytes(&cv_hdr->signal_level_percent, 1, fh, err, err_info);
 278         wtap_file_read_expected_bytes(&cv_hdr->rate, 1, fh, err, err_info);
 279         wtap_file_read_expected_bytes(&cv_hdr->band, 1, fh, err, err_info);
 280         wtap_file_read_expected_bytes(&cv_hdr->channel, 1, fh, err, err_info);
 281         wtap_file_read_expected_bytes(&cv_hdr->direction, 1, fh, err, err_info);
 282         wtap_file_read_expected_bytes(&cv_hdr->signal_level_dbm, 1, fh, err, err_info);
 283         wtap_file_read_expected_bytes(&cv_hdr->noise_level, 1, fh, err, err_info);
 284
 285         /* Convert multi-byte values from little endian to host endian format */
 286         cv_hdr->data_len = GUINT16_FROM_LE(cv_hdr->data_len);
 287         cv_hdr->source_data_len = GUINT16_FROM_LE(cv_hdr->source_data_len);
 288         cv_hdr->year = GUINT16_FROM_LE(cv_hdr->year);
 289         cv_hdr->usecs = GUINT32_FROM_LE(cv_hdr->usecs);
 290
 291         return TRUE;
 292 }
 293
 294 /* Returns 0 if we can write out the specified encapsulation type
 295  * into a CommView format file. */
 296 int commview_dump_can_write_encap(int encap)
 297 {
 298         switch (encap) {
 299
 300         case WTAP_ENCAP_ETHERNET :
 301         case WTAP_ENCAP_IEEE_802_11 :
 302         case WTAP_ENCAP_IEEE_802_11_WITH_RADIO :
 303         case WTAP_ENCAP_TOKEN_RING :
 304         case WTAP_ENCAP_PER_PACKET :
 305                 return 0;
 306
 307         default:
 308                 return WTAP_ERR_UNSUPPORTED_ENCAP;
 309         }
 310 }
 311
 312 /* Returns TRUE on success, FALSE on failure;
 313    sets "*err" to an error code on failure */
 314 gboolean commview_dump_open(wtap_dumper *wdh, int *err _U_)
 315 {
 316         wdh->subtype_write = commview_dump;
 317         wdh->subtype_close = NULL;
 318
 319         /* There is no file header to write out */
 320         wdh->bytes_dumped = 0;
 321
 322         return TRUE;
 323 }
 324
 325 /* Write a record for a packet to a dump file.
 326  * Returns TRUE on success, FALSE on failure. */
 327 static gboolean commview_dump(wtap_dumper *wdh,
 328                               const struct wtap_pkthdr *phdr,
 329                               const union wtap_pseudo_header *pseudo_header,
 330                               const guchar *pd, int *err)
 331 {
 332         commview_header_t cv_hdr;
 333         struct tm *tm;
 334
 335         memset(&cv_hdr, 0, sizeof(cv_hdr));
 336
 337         cv_hdr.data_len = GUINT16_TO_LE((guint16)phdr->caplen);
 338         cv_hdr.source_data_len = GUINT16_TO_LE((guint16)phdr->caplen);
 339         cv_hdr.version = 0;
 340
 341         tm = localtime(&phdr->ts.secs);
 342         cv_hdr.year = tm->tm_year + 1900;
 343         cv_hdr.month = tm->tm_mon + 1;
 344         cv_hdr.day = tm->tm_mday;
 345         cv_hdr.hours = tm->tm_hour;
 346         cv_hdr.minutes = tm->tm_min;
 347         cv_hdr.seconds = tm->tm_sec;
 348         cv_hdr.usecs = GUINT32_TO_LE(phdr->ts.nsecs / 1000);
 349
 350         switch(phdr->pkt_encap) {
 351
 352         case WTAP_ENCAP_ETHERNET :
 353                 cv_hdr.flags |= MEDIUM_ETHERNET;
 354                 break;
 355
 356         case WTAP_ENCAP_IEEE_802_11 :
 357                 cv_hdr.flags |=  MEDIUM_WIFI;
 358                 break;
 359
 360         case WTAP_ENCAP_IEEE_802_11_WITH_RADIO :
 361                 cv_hdr.flags |=  MEDIUM_WIFI;
 362
 363                 cv_hdr.channel = pseudo_header->ieee_802_11.channel;
 364                 cv_hdr.rate = pseudo_header->ieee_802_11.data_rate;
 365                 cv_hdr.signal_level_percent = pseudo_header->ieee_802_11.signal_level;
 366                 break;
 367
 368         case WTAP_ENCAP_TOKEN_RING :
 369                 cv_hdr.flags |= MEDIUM_TOKEN_RING;
 370                 break;
 371
 372         default :
 373                 *err = WTAP_ERR_UNSUPPORTED_ENCAP;
 374                 return FALSE;
 375         }
 376
 377         if (!wtap_dump_file_write(wdh, &cv_hdr.data_len, 2, err))
 378                 return FALSE;
 379         if (!wtap_dump_file_write(wdh, &cv_hdr.source_data_len, 2, err))
 380                 return FALSE;
 381         if (!wtap_dump_file_write(wdh, &cv_hdr.version, 1, err))
 382                 return FALSE;
 383         if (!wtap_dump_file_write(wdh, &cv_hdr.year, 2, err))
 384                 return FALSE;
 385         if (!wtap_dump_file_write(wdh, &cv_hdr.month, 1, err))
 386                 return FALSE;
 387         if (!wtap_dump_file_write(wdh, &cv_hdr.day, 1, err))
 388                 return FALSE;
 389         if (!wtap_dump_file_write(wdh, &cv_hdr.hours, 1, err))
 390                 return FALSE;
 391         if (!wtap_dump_file_write(wdh, &cv_hdr.minutes, 1, err))
 392                 return FALSE;
 393         if (!wtap_dump_file_write(wdh, &cv_hdr.seconds, 1, err))
 394                 return FALSE;
 395         if (!wtap_dump_file_write(wdh, &cv_hdr.usecs, 4, err))
 396                 return FALSE;
 397         if (!wtap_dump_file_write(wdh, &cv_hdr.flags, 1, err))
 398                 return FALSE;
 399         if (!wtap_dump_file_write(wdh, &cv_hdr.signal_level_percent, 1, err))
 400                 return FALSE;
 401         if (!wtap_dump_file_write(wdh, &cv_hdr.rate, 1, err))
 402                 return FALSE;
 403         if (!wtap_dump_file_write(wdh, &cv_hdr.band, 1, err))
 404                 return FALSE;
 405         if (!wtap_dump_file_write(wdh, &cv_hdr.channel, 1, err))
 406                 return FALSE;
 407         if (!wtap_dump_file_write(wdh, &cv_hdr.direction, 1, err))
 408                 return FALSE;
 409         if (!wtap_dump_file_write(wdh, &cv_hdr.signal_level_dbm, 2, err))
 410                 return FALSE;
 411         if (!wtap_dump_file_write(wdh, &cv_hdr.noise_level, 2, err))
 412                 return FALSE;
 413         wdh->bytes_dumped += COMMVIEW_HEADER_SIZE;
 414
 415         if (!wtap_dump_file_write(wdh, pd, phdr->caplen, err))
 416                 return FALSE;
 417         wdh->bytes_dumped += phdr->caplen;
 418
 419         return TRUE;
 420 }