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 #include "config.h"
  34
  35 #include <glib.h>
  36 #include <stdio.h>
  37 #include <stdlib.h>
  38 #include <errno.h>
  39 #include <string.h>
  40
  41 #include "wtap.h"
  42 #include "wtap-int.h"
  43 #include "buffer.h"
  44 #include "file_wrappers.h"
  45 #include "commview.h"
  46
  47 typedef struct commview_header {
  48         guint16         data_len;
  49         guint16         source_data_len;
  50         guint8          version;
  51         guint16         year;
  52         guint8          month;
  53         guint8          day;
  54         guint8          hours;
  55         guint8          minutes;
  56         guint8          seconds;
  57         guint32         usecs;
  58         guint8          flags;          /* Bit-field positions defined below */
  59         guint8          signal_level_percent;
  60         guint8          rate;
  61         guint8          band;
  62         guint8          channel;
  63         guint8          direction;      /* Or for WiFi, high order byte of
  64                                          * packet rate. */
  65         guint8          signal_level_dbm;
  66         guint8          noise_level;    /* In dBm (WiFi only) */
  67 } commview_header_t;
  68
  69 #define COMMVIEW_HEADER_SIZE 24
  70
  71 /* Bit-field positions for various fields in the flags variable of the header */
  72 #define FLAGS_MEDIUM            0x0F
  73 #define FLAGS_DECRYPTED         0x10
  74 #define FLAGS_BROKEN            0x20
  75 #define FLAGS_COMPRESSED        0x40
  76 #define FLAGS_RESERVED          0x80
  77
  78 /* Capture mediums as defined by the commview file format */
  79 #define MEDIUM_ETHERNET         0
  80 #define MEDIUM_WIFI             1
  81 #define MEDIUM_TOKEN_RING       2
  82
  83 static gboolean commview_read(wtap *wth, int *err, gchar **err_info,
  84                               gint64 *data_offset);
  85 static gboolean commview_seek_read(wtap *wth, gint64 seek_off,
  86                                    struct wtap_pkthdr *phdr,
  87                                    Buffer *buf, int length, int *err,
  88                                    gchar **err_info);
  89 static gboolean commview_read_header(commview_header_t *cv_hdr, FILE_T fh,
  90                                      int *err, gchar **err_info);
  91 static gboolean commview_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
  92                               const guint8 *pd, int *err);
  93
  94 int commview_open(wtap *wth, int *err, gchar **err_info)
  95 {
  96         commview_header_t cv_hdr;
  97
  98         if(!commview_read_header(&cv_hdr, wth->fh, err, err_info)) {
  99                 if (*err != 0 && *err != WTAP_ERR_SHORT_READ)
 100                         return -1;
 101                 return 0;
 102         }
 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->file_type = WTAP_FILE_COMMVIEW;
 128         wth->file_encap = WTAP_ENCAP_PER_PACKET;
 129         wth->tsprecision = WTAP_FILE_TSPREC_USEC;
 130
 131         return 1; /* Our kind of file */
 132 }
 133
 134 static int
 135 commview_read_packet(FILE_T fh, struct wtap_pkthdr *phdr, Buffer *buf,
 136     int *err, gchar **err_info)
 137 {
 138         commview_header_t cv_hdr;
 139         struct tm tm;
 140
 141         if(!commview_read_header(&cv_hdr, fh, err, err_info))
 142                 return FALSE;
 143
 144         switch(cv_hdr.flags & FLAGS_MEDIUM) {
 145
 146         case MEDIUM_ETHERNET :
 147                 phdr->pkt_encap = WTAP_ENCAP_ETHERNET;
 148                 phdr->pseudo_header.eth.fcs_len = -1; /* Unknown */
 149                 break;
 150
 151         case MEDIUM_WIFI :
 152                 phdr->pkt_encap = WTAP_ENCAP_IEEE_802_11_WITH_RADIO;
 153                 phdr->pseudo_header.ieee_802_11.fcs_len = -1; /* Unknown */
 154                 phdr->pseudo_header.ieee_802_11.channel = cv_hdr.channel;
 155                 phdr->pseudo_header.ieee_802_11.data_rate =
 156                     cv_hdr.rate | (cv_hdr.direction << 8);
 157                 phdr->pseudo_header.ieee_802_11.signal_level = cv_hdr.signal_level_percent;
 158                 break;
 159
 160         case MEDIUM_TOKEN_RING :
 161                 phdr->pkt_encap = WTAP_ENCAP_TOKEN_RING;
 162                 break;
 163
 164         default :
 165                 *err = WTAP_ERR_BAD_FILE;
 166                 *err_info = g_strdup_printf("commview: unsupported encap: %u",
 167                                             cv_hdr.flags & FLAGS_MEDIUM);
 168                 return FALSE;
 169         }
 170
 171         tm.tm_year = cv_hdr.year - 1900;
 172         tm.tm_mon = cv_hdr.month - 1;
 173         tm.tm_mday = cv_hdr.day;
 174         tm.tm_hour = cv_hdr.hours;
 175         tm.tm_min = cv_hdr.minutes;
 176         tm.tm_sec = cv_hdr.seconds;
 177         tm.tm_isdst = -1;
 178
 179         phdr->presence_flags = WTAP_HAS_TS;
 180
 181         phdr->len = cv_hdr.data_len;
 182         phdr->caplen = cv_hdr.data_len;
 183
 184         phdr->ts.secs = mktime(&tm);
 185         phdr->ts.nsecs = cv_hdr.usecs * 1000;
 186
 187         return wtap_read_packet_bytes(fh, buf, phdr->caplen, err, err_info);
 188 }
 189
 190 static gboolean
 191 commview_read(wtap *wth, int *err, gchar **err_info, gint64 *data_offset)
 192 {
 193         *data_offset = file_tell(wth->fh);
 194
 195         return commview_read_packet(wth->fh, &wth->phdr, wth->frame_buffer, err,
 196             err_info);
 197 }
 198
 199 static gboolean
 200 commview_seek_read(wtap *wth, gint64 seek_off, struct wtap_pkthdr *phdr,
 201                    Buffer *buf, int length _U_, int *err, gchar **err_info)
 202 {
 203         if(file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1)
 204                 return FALSE;
 205
 206         return commview_read_packet(wth->random_fh, phdr, buf, err, err_info);
 207 }
 208
 209 static gboolean
 210 commview_read_header(commview_header_t *cv_hdr, FILE_T fh, int *err,
 211     gchar **err_info)
 212 {
 213         wtap_file_read_expected_bytes(&cv_hdr->data_len, 2, fh, err, err_info);
 214         wtap_file_read_expected_bytes(&cv_hdr->source_data_len, 2, fh, err, err_info);
 215         wtap_file_read_expected_bytes(&cv_hdr->version, 1, fh, err, err_info);
 216         wtap_file_read_expected_bytes(&cv_hdr->year, 2, fh, err, err_info);
 217         wtap_file_read_expected_bytes(&cv_hdr->month, 1, fh, err, err_info);
 218         wtap_file_read_expected_bytes(&cv_hdr->day, 1, fh, err, err_info);
 219         wtap_file_read_expected_bytes(&cv_hdr->hours, 1, fh, err, err_info);
 220         wtap_file_read_expected_bytes(&cv_hdr->minutes, 1, fh, err, err_info);
 221         wtap_file_read_expected_bytes(&cv_hdr->seconds, 1, fh, err, err_info);
 222         wtap_file_read_expected_bytes(&cv_hdr->usecs, 4, fh, err, err_info);
 223         wtap_file_read_expected_bytes(&cv_hdr->flags, 1, fh, err, err_info);
 224         wtap_file_read_expected_bytes(&cv_hdr->signal_level_percent, 1, fh, err, err_info);
 225         wtap_file_read_expected_bytes(&cv_hdr->rate, 1, fh, err, err_info);
 226         wtap_file_read_expected_bytes(&cv_hdr->band, 1, fh, err, err_info);
 227         wtap_file_read_expected_bytes(&cv_hdr->channel, 1, fh, err, err_info);
 228         wtap_file_read_expected_bytes(&cv_hdr->direction, 1, fh, err, err_info);
 229         wtap_file_read_expected_bytes(&cv_hdr->signal_level_dbm, 1, fh, err, err_info);
 230         wtap_file_read_expected_bytes(&cv_hdr->noise_level, 1, fh, err, err_info);
 231
 232         /* Convert multi-byte values from little endian to host endian format */
 233         cv_hdr->data_len = GUINT16_FROM_LE(cv_hdr->data_len);
 234         cv_hdr->source_data_len = GUINT16_FROM_LE(cv_hdr->source_data_len);
 235         cv_hdr->year = GUINT16_FROM_LE(cv_hdr->year);
 236         cv_hdr->usecs = GUINT32_FROM_LE(cv_hdr->usecs);
 237
 238         return TRUE;
 239 }
 240
 241 /* Returns 0 if we can write out the specified encapsulation type
 242  * into a CommView format file. */
 243 int commview_dump_can_write_encap(int encap)
 244 {
 245         switch (encap) {
 246
 247         case WTAP_ENCAP_ETHERNET :
 248         case WTAP_ENCAP_IEEE_802_11 :
 249         case WTAP_ENCAP_IEEE_802_11_WITH_RADIO :
 250         case WTAP_ENCAP_TOKEN_RING :
 251         case WTAP_ENCAP_PER_PACKET :
 252                 return 0;
 253
 254         default:
 255                 return WTAP_ERR_UNSUPPORTED_ENCAP;
 256         }
 257 }
 258
 259 /* Returns TRUE on success, FALSE on failure;
 260    sets "*err" to an error code on failure */
 261 gboolean commview_dump_open(wtap_dumper *wdh, int *err _U_)
 262 {
 263         wdh->subtype_write = commview_dump;
 264         wdh->subtype_close = NULL;
 265
 266         /* There is no file header to write out */
 267         wdh->bytes_dumped = 0;
 268
 269         return TRUE;
 270 }
 271
 272 /* Write a record for a packet to a dump file.
 273  * Returns TRUE on success, FALSE on failure. */
 274 static gboolean commview_dump(wtap_dumper *wdh,
 275                               const struct wtap_pkthdr *phdr,
 276                               const guint8 *pd, int *err)
 277 {
 278         commview_header_t cv_hdr;
 279         struct tm *tm;
 280
 281         memset(&cv_hdr, 0, sizeof(cv_hdr));
 282
 283         cv_hdr.data_len = GUINT16_TO_LE((guint16)phdr->caplen);
 284         cv_hdr.source_data_len = GUINT16_TO_LE((guint16)phdr->caplen);
 285         cv_hdr.version = 0;
 286
 287         tm = localtime(&phdr->ts.secs);
 288         cv_hdr.year = tm->tm_year + 1900;
 289         cv_hdr.month = tm->tm_mon + 1;
 290         cv_hdr.day = tm->tm_mday;
 291         cv_hdr.hours = tm->tm_hour;
 292         cv_hdr.minutes = tm->tm_min;
 293         cv_hdr.seconds = tm->tm_sec;
 294         cv_hdr.usecs = GUINT32_TO_LE(phdr->ts.nsecs / 1000);
 295
 296         switch(phdr->pkt_encap) {
 297
 298         case WTAP_ENCAP_ETHERNET :
 299                 cv_hdr.flags |= MEDIUM_ETHERNET;
 300                 break;
 301
 302         case WTAP_ENCAP_IEEE_802_11 :
 303                 cv_hdr.flags |=  MEDIUM_WIFI;
 304                 break;
 305
 306         case WTAP_ENCAP_IEEE_802_11_WITH_RADIO :
 307                 cv_hdr.flags |=  MEDIUM_WIFI;
 308
 309                 cv_hdr.channel = phdr->pseudo_header.ieee_802_11.channel;
 310                 cv_hdr.rate = (guint8)(phdr->pseudo_header.ieee_802_11.data_rate & 0xFF);
 311                 cv_hdr.direction = (guint8)((phdr->pseudo_header.ieee_802_11.data_rate >> 8) & 0xFF);
 312                 cv_hdr.signal_level_percent = phdr->pseudo_header.ieee_802_11.signal_level;
 313                 break;
 314
 315         case WTAP_ENCAP_TOKEN_RING :
 316                 cv_hdr.flags |= MEDIUM_TOKEN_RING;
 317                 break;
 318
 319         default :
 320                 *err = WTAP_ERR_UNSUPPORTED_ENCAP;
 321                 return FALSE;
 322         }
 323
 324         if (!wtap_dump_file_write(wdh, &cv_hdr.data_len, 2, err))
 325                 return FALSE;
 326         if (!wtap_dump_file_write(wdh, &cv_hdr.source_data_len, 2, err))
 327                 return FALSE;
 328         if (!wtap_dump_file_write(wdh, &cv_hdr.version, 1, err))
 329                 return FALSE;
 330         if (!wtap_dump_file_write(wdh, &cv_hdr.year, 2, err))
 331                 return FALSE;
 332         if (!wtap_dump_file_write(wdh, &cv_hdr.month, 1, err))
 333                 return FALSE;
 334         if (!wtap_dump_file_write(wdh, &cv_hdr.day, 1, err))
 335                 return FALSE;
 336         if (!wtap_dump_file_write(wdh, &cv_hdr.hours, 1, err))
 337                 return FALSE;
 338         if (!wtap_dump_file_write(wdh, &cv_hdr.minutes, 1, err))
 339                 return FALSE;
 340         if (!wtap_dump_file_write(wdh, &cv_hdr.seconds, 1, err))
 341                 return FALSE;
 342         if (!wtap_dump_file_write(wdh, &cv_hdr.usecs, 4, err))
 343                 return FALSE;
 344         if (!wtap_dump_file_write(wdh, &cv_hdr.flags, 1, err))
 345                 return FALSE;
 346         if (!wtap_dump_file_write(wdh, &cv_hdr.signal_level_percent, 1, err))
 347                 return FALSE;
 348         if (!wtap_dump_file_write(wdh, &cv_hdr.rate, 1, err))
 349                 return FALSE;
 350         if (!wtap_dump_file_write(wdh, &cv_hdr.band, 1, err))
 351                 return FALSE;
 352         if (!wtap_dump_file_write(wdh, &cv_hdr.channel, 1, err))
 353                 return FALSE;
 354         if (!wtap_dump_file_write(wdh, &cv_hdr.direction, 1, err))
 355                 return FALSE;
 356         if (!wtap_dump_file_write(wdh, &cv_hdr.signal_level_dbm, 2, err))
 357                 return FALSE;
 358         if (!wtap_dump_file_write(wdh, &cv_hdr.noise_level, 2, err))
 359                 return FALSE;
 360         wdh->bytes_dumped += COMMVIEW_HEADER_SIZE;
 361
 362         if (!wtap_dump_file_write(wdh, pd, phdr->caplen, err))
 363                 return FALSE;
 364         wdh->bytes_dumped += phdr->caplen;
 365
 366         return TRUE;
 367 }