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                                        struct wtap_pkthdr *phdr,
  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                 if (*err != 0 && *err != WTAP_ERR_SHORT_READ)
  66                         return -1;
  67                 return 0;
  68         }
  69
  70         if (file_read(&type, 1, wth->fh) <= 0) {
  71                 *err = file_error(wth->fh, err_info);
  72                 if (*err != 0 && *err != WTAP_ERR_SHORT_READ)
  73                         return -1;
  74                 return 0;
  75         }
  76
  77         /* Verify this file belongs to us */
  78         if (!((8 <= pl_hdr.len) && (pl_hdr.len < 65536) &&
  79               (type < 0x04 || type == 0xFB || type == 0xFC || type == 0xFE || type == 0xFF)))
  80                 return 0;
  81
  82         /* No file header. Reset the fh to 0 so we can read the first packet */
  83         if (file_seek(wth->fh, 0, SEEK_SET, err) == -1)
  84                 return -1;
  85
  86         /* Set up the pointers to the handlers for this file type */
  87         wth->subtype_read = packetlogger_read;
  88         wth->subtype_seek_read = packetlogger_seek_read;
  89
  90         wth->file_type = WTAP_FILE_PACKETLOGGER;
  91         wth->file_encap = WTAP_ENCAP_PACKETLOGGER;
  92         wth->tsprecision = WTAP_FILE_TSPREC_USEC;
  93
  94         return 1; /* Our kind of file */
  95 }
  96
  97 static gboolean
  98 packetlogger_read(wtap *wth, int *err, gchar **err_info, gint64 *data_offset)
  99 {
 100         packetlogger_header_t pl_hdr;
 101         guint bytes_read;
 102
 103         *data_offset = file_tell(wth->fh);
 104
 105         if(!packetlogger_read_header(&pl_hdr, wth->fh, err, err_info))
 106                 return FALSE;
 107
 108         if (pl_hdr.len < 8) {
 109                 *err = WTAP_ERR_BAD_FILE;
 110                 *err_info = g_strdup_printf("packetlogger: record length %u is too small", pl_hdr.len);
 111                 return FALSE;
 112         }
 113         if (pl_hdr.len - 8 > WTAP_MAX_PACKET_SIZE) {
 114                 /*
 115                  * Probably a corrupt capture file; don't blow up trying
 116                  * to allocate space for an immensely-large packet.
 117                  */
 118                 *err = WTAP_ERR_BAD_FILE;
 119                 *err_info = g_strdup_printf("packetlogger: File has %u-byte packet, bigger than maximum of %u",
 120                     pl_hdr.len - 8, WTAP_MAX_PACKET_SIZE);
 121                 return FALSE;
 122         }
 123
 124         buffer_assure_space(wth->frame_buffer, pl_hdr.len - 8);
 125         bytes_read = file_read(buffer_start_ptr(wth->frame_buffer),
 126                                pl_hdr.len - 8,
 127                                wth->fh);
 128         if(bytes_read != pl_hdr.len - 8) {
 129                 *err = file_error(wth->fh, err_info);
 130                 if(*err == 0)
 131                         *err = WTAP_ERR_SHORT_READ;
 132
 133                 return FALSE;
 134         }
 135
 136         wth->phdr.presence_flags = WTAP_HAS_TS;
 137
 138         wth->phdr.len = pl_hdr.len - 8;
 139         wth->phdr.caplen = pl_hdr.len - 8;
 140
 141         wth->phdr.ts.secs = (time_t) (pl_hdr.ts >> 32);
 142         wth->phdr.ts.nsecs = (int)((pl_hdr.ts & 0xFFFFFFFF) * 1000);
 143
 144         return TRUE;
 145 }
 146
 147 static gboolean
 148 packetlogger_seek_read(wtap *wth, gint64 seek_off, struct wtap_pkthdr *phdr _U_,
 149                        guint8 *pd, int length, int *err,
 150                        gchar **err_info)
 151 {
 152         packetlogger_header_t pl_hdr;
 153         guint bytes_read;
 154
 155         if(file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1)
 156                 return FALSE;
 157
 158         if(!packetlogger_read_header(&pl_hdr, wth->random_fh, err, err_info)) {
 159                 if(*err == 0)
 160                         *err = WTAP_ERR_SHORT_READ;
 161
 162                 return FALSE;
 163         }
 164
 165         if(length != (int)pl_hdr.len - 8) {
 166                 *err = WTAP_ERR_BAD_FILE;
 167                 *err_info = g_strdup_printf("packetlogger: record length %u doesn't match requested length %d", pl_hdr.len, length);
 168                 return FALSE;
 169         }
 170
 171         bytes_read = file_read(pd, pl_hdr.len - 8, wth->random_fh);
 172         if(bytes_read != (pl_hdr.len - 8)) {
 173                 *err = file_error(wth->random_fh, err_info);
 174                 if(*err == 0)
 175                         *err = WTAP_ERR_SHORT_READ;
 176
 177                 return FALSE;
 178         }
 179
 180         return TRUE;
 181 }
 182
 183 static gboolean
 184 packetlogger_read_header(packetlogger_header_t *pl_hdr, FILE_T fh, int *err,
 185                          gchar **err_info)
 186 {
 187         wtap_file_read_expected_bytes(&pl_hdr->len, 4, fh, err, err_info);
 188         wtap_file_read_expected_bytes(&pl_hdr->ts, 8, fh, err, err_info);
 189
 190         /* Convert multi-byte values from big endian to host endian */
 191         pl_hdr->len = GUINT32_FROM_BE(pl_hdr->len);
 192         pl_hdr->ts = GUINT64_FROM_BE(pl_hdr->ts);
 193
 194         return TRUE;
 195 }