wiretap/packetlogger.c

   1 /* packetlogger.c
   2  * Routines for opening Apple's (Bluetooth) PacketLogger file format captures
   3  * Copyright 2008-2009, 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 commview.c, Linux's BlueZ-Gnome Analyzer program and hexdumps of
  12  * the output files from Apple's PacketLogger tool.
  13  *
  14  * This program is free software; you can redistribute it and/or
  15  * modify it under the terms of the GNU General Public License
  16  * as published by the Free Software Foundation; either version 2
  17  * of the License, or (at your option) any later version.
  18  *
  19  * This program is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with this program; if not, write to the Free Software
  26  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
  27  * USA.
  28  */
  29
  30 #include "config.h"
  31
  32 #include <glib.h>
  33 #include <stdio.h>
  34 #include <stdlib.h>
  35 #include <errno.h>
  36 #include <string.h>
  37
  38 #include "wtap.h"
  39 #include "wtap-int.h"
  40 #include "buffer.h"
  41 #include "file_wrappers.h"
  42 #include "packetlogger.h"
  43
  44 typedef struct packetlogger_header {
  45         guint32 len;
  46         guint64 ts;
  47 } packetlogger_header_t;
  48
  49 static gboolean packetlogger_read(wtap *wth, int *err, gchar **err_info,
  50                                   gint64 *data_offset);
  51 static gboolean packetlogger_seek_read(wtap *wth, gint64 seek_off,
  52                                        union wtap_pseudo_header *pseudo_header _U_,
  53                                        guint8 *pd, int length, int *err,
  54                                        gchar **err_info);
  55 static gboolean packetlogger_read_header(packetlogger_header_t *pl_hdr,
  56                                          FILE_T fh, int *err, gchar **err_info);
  57
  58
  59 int packetlogger_open(wtap *wth, int *err, gchar **err_info)
  60 {
  61         packetlogger_header_t pl_hdr;
  62         guint8 type;
  63
  64         if(!packetlogger_read_header(&pl_hdr, wth->fh, err, err_info))
  65                 return -1;
  66
  67         if (file_read(&type, 1, wth->fh) <= 0)
  68                 return -1;
  69
  70         /* Verify this file belongs to us */
  71         if (!((8 <= pl_hdr.len) && (pl_hdr.len < 65536) &&
  72               (type < 0x04 || type == 0xFB || type == 0xFC || type == 0xFE || type == 0xFF)))
  73                 return 0;
  74
  75         /* No file header. Reset the fh to 0 so we can read the first packet */
  76         if (file_seek(wth->fh, 0, SEEK_SET, err) == -1)
  77                 return -1;
  78
  79         /* Set up the pointers to the handlers for this file type */
  80         wth->subtype_read = packetlogger_read;
  81         wth->subtype_seek_read = packetlogger_seek_read;
  82
  83         wth->file_type = WTAP_FILE_PACKETLOGGER;
  84         wth->file_encap = WTAP_ENCAP_PACKETLOGGER;
  85         wth->tsprecision = WTAP_FILE_TSPREC_USEC;
  86
  87         return 1; /* Our kind of file */
  88 }
  89
  90 static gboolean
  91 packetlogger_read(wtap *wth, int *err, gchar **err_info, gint64 *data_offset)
  92 {
  93         packetlogger_header_t pl_hdr;
  94         guint bytes_read;
  95
  96         *data_offset = file_tell(wth->fh);
  97
  98         if(!packetlogger_read_header(&pl_hdr, wth->fh, err, err_info))
  99                 return FALSE;
 100
 101         if (pl_hdr.len < 8) {
 102                 *err = WTAP_ERR_BAD_FILE;
 103                 *err_info = g_strdup_printf("packetlogger: record length %u is too small", pl_hdr.len);
 104                 return FALSE;
 105         }
 106         if (pl_hdr.len - 8 > WTAP_MAX_PACKET_SIZE) {
 107                 /*
 108                  * Probably a corrupt capture file; don't blow up trying
 109                  * to allocate space for an immensely-large packet.
 110                  */
 111                 *err = WTAP_ERR_BAD_FILE;
 112                 *err_info = g_strdup_printf("packetlogger: File has %u-byte packet, bigger than maximum of %u",
 113                     pl_hdr.len - 8, WTAP_MAX_PACKET_SIZE);
 114                 return FALSE;
 115         }
 116
 117         buffer_assure_space(wth->frame_buffer, pl_hdr.len - 8);
 118         bytes_read = file_read(buffer_start_ptr(wth->frame_buffer),
 119                                pl_hdr.len - 8,
 120                                wth->fh);
 121         if(bytes_read != pl_hdr.len - 8) {
 122                 *err = file_error(wth->fh, err_info);
 123                 if(*err == 0)
 124                         *err = WTAP_ERR_SHORT_READ;
 125
 126                 return FALSE;
 127         }
 128
 129         wth->phdr.presence_flags = WTAP_HAS_TS;
 130
 131         wth->phdr.len = pl_hdr.len - 8;
 132         wth->phdr.caplen = pl_hdr.len - 8;
 133
 134         wth->phdr.ts.secs = (time_t) (pl_hdr.ts >> 32);
 135         wth->phdr.ts.nsecs = (int)((pl_hdr.ts & 0xFFFFFFFF) * 1000);
 136
 137         return TRUE;
 138 }
 139
 140 static gboolean
 141 packetlogger_seek_read(wtap *wth, gint64 seek_off, union wtap_pseudo_header
 142                        *pseudo_header _U_, guint8 *pd, int length, int *err,
 143                        gchar **err_info)
 144 {
 145         packetlogger_header_t pl_hdr;
 146         guint bytes_read;
 147
 148         if(file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1)
 149                 return FALSE;
 150
 151         if(!packetlogger_read_header(&pl_hdr, wth->random_fh, err, err_info)) {
 152                 if(*err == 0)
 153                         *err = WTAP_ERR_SHORT_READ;
 154
 155                 return FALSE;
 156         }
 157
 158         if(length != (int)pl_hdr.len - 8) {
 159                 *err = WTAP_ERR_BAD_FILE;
 160                 *err_info = g_strdup_printf("packetlogger: record length %u doesn't match requested length %d", pl_hdr.len, length);
 161                 return FALSE;
 162         }
 163
 164         bytes_read = file_read(pd, pl_hdr.len - 8, wth->random_fh);
 165         if(bytes_read != (pl_hdr.len - 8)) {
 166                 *err = file_error(wth->random_fh, err_info);
 167                 if(*err == 0)
 168                         *err = WTAP_ERR_SHORT_READ;
 169
 170                 return FALSE;
 171         }
 172
 173         return TRUE;
 174 }
 175
 176 static gboolean
 177 packetlogger_read_header(packetlogger_header_t *pl_hdr, FILE_T fh, int *err,
 178                          gchar **err_info)
 179 {
 180         wtap_file_read_expected_bytes(&pl_hdr->len, 4, fh, err, err_info);
 181         wtap_file_read_expected_bytes(&pl_hdr->ts, 8, fh, err, err_info);
 182
 183         /* Convert multi-byte values from big endian to host endian */
 184         pl_hdr->len = GUINT32_FROM_BE(pl_hdr->len);
 185         pl_hdr->ts = GUINT64_FROM_BE(pl_hdr->ts);
 186
 187         return TRUE;
 188 }