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  * Wireshark - Network traffic analyzer
   6  * By Gerald Combs <gerald@wireshark.org>
   7  * Copyright 1998 Gerald Combs
   8  *
   9  * Based on commview.c, Linux's BlueZ-Gnome Analyzer program and hexdumps of
  10  * the output files from Apple's PacketLogger tool.
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
  25  * USA.
  26  */
  27
  28 #include "config.h"
  29
  30 #include <glib.h>
  31 #include <stdio.h>
  32 #include <stdlib.h>
  33 #include <errno.h>
  34 #include <string.h>
  35
  36 #include "wtap.h"
  37 #include "wtap-int.h"
  38 #include "buffer.h"
  39 #include "file_wrappers.h"
  40 #include "packetlogger.h"
  41
  42 typedef struct packetlogger_header {
  43         guint32 len;
  44         guint64 ts;
  45 } packetlogger_header_t;
  46
  47 static int packetlogger_read(wtap *wth, int *err, gchar **err_info,
  48                              gint64 *data_offset);
  49 static int packetlogger_seek_read(wtap *wth, gint64 seek_off,
  50                                   struct wtap_pkthdr *phdr,
  51                                   Buffer *buf, int *err, gchar **err_info);
  52 static gboolean packetlogger_read_header(packetlogger_header_t *pl_hdr,
  53                                          FILE_T fh, int *err, gchar **err_info);
  54 static gboolean packetlogger_read_packet(FILE_T fh, struct wtap_pkthdr *phdr,
  55                                          Buffer *buf, int *err,
  56                                          gchar **err_info);
  57
  58 int packetlogger_open(wtap *wth, int *err, gchar **err_info)
  59 {
  60         packetlogger_header_t pl_hdr;
  61         guint8 type;
  62
  63         if(!packetlogger_read_header(&pl_hdr, wth->fh, err, err_info)) {
  64                 if (*err != 0 && *err != WTAP_ERR_SHORT_READ)
  65                         return -1;
  66                 return 0;
  67         }
  68
  69         if (file_read(&type, 1, wth->fh) <= 0) {
  70                 *err = file_error(wth->fh, err_info);
  71                 if (*err != 0 && *err != WTAP_ERR_SHORT_READ)
  72                         return -1;
  73                 return 0;
  74         }
  75
  76         /* Verify this file belongs to us */
  77         if (!((8 <= pl_hdr.len) && (pl_hdr.len < 65536) &&
  78               (type < 0x04 || type == 0xFB || type == 0xFC || type == 0xFE || type == 0xFF)))
  79                 return 0;
  80
  81         /* No file header. Reset the fh to 0 so we can read the first packet */
  82         if (file_seek(wth->fh, 0, SEEK_SET, err) == -1)
  83                 return -1;
  84
  85         /* Set up the pointers to the handlers for this file type */
  86         wth->subtype_read = packetlogger_read;
  87         wth->subtype_seek_read = packetlogger_seek_read;
  88
  89         wth->file_type_subtype = WTAP_FILE_TYPE_SUBTYPE_PACKETLOGGER;
  90         wth->file_encap = WTAP_ENCAP_PACKETLOGGER;
  91         wth->tsprecision = WTAP_FILE_TSPREC_USEC;
  92
  93         return 1; /* Our kind of file */
  94 }
  95
  96 static int
  97 packetlogger_read(wtap *wth, int *err, gchar **err_info, gint64 *data_offset)
  98 {
  99         *data_offset = file_tell(wth->fh);
 100
 101         if (!packetlogger_read_packet(wth->fh, &wth->phdr,
 102             wth->frame_buffer, err, err_info))
 103                 return -1;
 104         return REC_TYPE_PACKET;
 105 }
 106
 107 static int
 108 packetlogger_seek_read(wtap *wth, gint64 seek_off, struct wtap_pkthdr *phdr,
 109                        Buffer *buf, int *err, gchar **err_info)
 110 {
 111         if(file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1)
 112                 return -1;
 113
 114         if(!packetlogger_read_packet(wth->random_fh, phdr, buf, err, err_info)) {
 115                 if(*err == 0)
 116                         *err = WTAP_ERR_SHORT_READ;
 117
 118                 return -1;
 119         }
 120         return REC_TYPE_PACKET;
 121 }
 122
 123 static gboolean
 124 packetlogger_read_header(packetlogger_header_t *pl_hdr, FILE_T fh, int *err,
 125                          gchar **err_info)
 126 {
 127         wtap_file_read_expected_bytes(&pl_hdr->len, 4, fh, err, err_info);
 128         wtap_file_read_expected_bytes(&pl_hdr->ts, 8, fh, err, err_info);
 129
 130         /* Convert multi-byte values from big endian to host endian */
 131         pl_hdr->len = GUINT32_FROM_BE(pl_hdr->len);
 132         pl_hdr->ts = GUINT64_FROM_BE(pl_hdr->ts);
 133
 134         return TRUE;
 135 }
 136
 137 static gboolean
 138 packetlogger_read_packet(FILE_T fh, struct wtap_pkthdr *phdr, Buffer *buf,
 139                          int *err, gchar **err_info)
 140 {
 141         packetlogger_header_t pl_hdr;
 142
 143         if(!packetlogger_read_header(&pl_hdr, fh, err, err_info))
 144                 return FALSE;
 145
 146         if (pl_hdr.len < 8) {
 147                 *err = WTAP_ERR_BAD_FILE;
 148                 *err_info = g_strdup_printf("packetlogger: record length %u is too small", pl_hdr.len);
 149                 return FALSE;
 150         }
 151         if (pl_hdr.len - 8 > WTAP_MAX_PACKET_SIZE) {
 152                 /*
 153                  * Probably a corrupt capture file; don't blow up trying
 154                  * to allocate space for an immensely-large packet.
 155                  */
 156                 *err = WTAP_ERR_BAD_FILE;
 157                 *err_info = g_strdup_printf("packetlogger: File has %u-byte packet, bigger than maximum of %u",
 158                     pl_hdr.len - 8, WTAP_MAX_PACKET_SIZE);
 159                 return FALSE;
 160         }
 161
 162         phdr->presence_flags = WTAP_HAS_TS;
 163
 164         phdr->len = pl_hdr.len - 8;
 165         phdr->caplen = pl_hdr.len - 8;
 166
 167         phdr->ts.secs = (time_t) (pl_hdr.ts >> 32);
 168         phdr->ts.nsecs = (int)((pl_hdr.ts & 0xFFFFFFFF) * 1000);
 169
 170         return wtap_read_packet_bytes(fh, buf, phdr->caplen, err, err_info);
 171 }