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                                        Buffer *buf, 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 static gboolean packetlogger_read_packet(FILE_T fh, struct wtap_pkthdr *phdr,
  58                                          Buffer *buf, int *err,
  59                                          gchar **err_info);
  60
  61 int packetlogger_open(wtap *wth, int *err, gchar **err_info)
  62 {
  63         packetlogger_header_t pl_hdr;
  64         guint8 type;
  65
  66         if(!packetlogger_read_header(&pl_hdr, wth->fh, err, err_info)) {
  67                 if (*err != 0 && *err != WTAP_ERR_SHORT_READ)
  68                         return -1;
  69                 return 0;
  70         }
  71
  72         if (file_read(&type, 1, wth->fh) <= 0) {
  73                 *err = file_error(wth->fh, err_info);
  74                 if (*err != 0 && *err != WTAP_ERR_SHORT_READ)
  75                         return -1;
  76                 return 0;
  77         }
  78
  79         /* Verify this file belongs to us */
  80         if (!((8 <= pl_hdr.len) && (pl_hdr.len < 65536) &&
  81               (type < 0x04 || type == 0xFB || type == 0xFC || type == 0xFE || type == 0xFF)))
  82                 return 0;
  83
  84         /* No file header. Reset the fh to 0 so we can read the first packet */
  85         if (file_seek(wth->fh, 0, SEEK_SET, err) == -1)
  86                 return -1;
  87
  88         /* Set up the pointers to the handlers for this file type */
  89         wth->subtype_read = packetlogger_read;
  90         wth->subtype_seek_read = packetlogger_seek_read;
  91
  92         wth->file_type_subtype = WTAP_FILE_TYPE_SUBTYPE_PACKETLOGGER;
  93         wth->file_encap = WTAP_ENCAP_PACKETLOGGER;
  94         wth->tsprecision = WTAP_FILE_TSPREC_USEC;
  95
  96         return 1; /* Our kind of file */
  97 }
  98
  99 static gboolean
 100 packetlogger_read(wtap *wth, int *err, gchar **err_info, gint64 *data_offset)
 101 {
 102         *data_offset = file_tell(wth->fh);
 103
 104         return packetlogger_read_packet(wth->fh, &wth->phdr,
 105             wth->frame_buffer, err, err_info);
 106 }
 107
 108 static gboolean
 109 packetlogger_seek_read(wtap *wth, gint64 seek_off, struct wtap_pkthdr *phdr,
 110                        Buffer *buf, int length _U_, int *err, gchar **err_info)
 111 {
 112         if(file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1)
 113                 return FALSE;
 114
 115         if(!packetlogger_read_packet(wth->random_fh, phdr, buf, err, err_info)) {
 116                 if(*err == 0)
 117                         *err = WTAP_ERR_SHORT_READ;
 118
 119                 return FALSE;
 120         }
 121         return TRUE;
 122 }
 123
 124 static gboolean
 125 packetlogger_read_header(packetlogger_header_t *pl_hdr, FILE_T fh, int *err,
 126                          gchar **err_info)
 127 {
 128         wtap_file_read_expected_bytes(&pl_hdr->len, 4, fh, err, err_info);
 129         wtap_file_read_expected_bytes(&pl_hdr->ts, 8, fh, err, err_info);
 130
 131         /* Convert multi-byte values from big endian to host endian */
 132         pl_hdr->len = GUINT32_FROM_BE(pl_hdr->len);
 133         pl_hdr->ts = GUINT64_FROM_BE(pl_hdr->ts);
 134
 135         return TRUE;
 136 }
 137
 138 static gboolean
 139 packetlogger_read_packet(FILE_T fh, struct wtap_pkthdr *phdr, Buffer *buf,
 140                          int *err, gchar **err_info)
 141 {
 142         packetlogger_header_t pl_hdr;
 143
 144         if(!packetlogger_read_header(&pl_hdr, fh, err, err_info))
 145                 return FALSE;
 146
 147         if (pl_hdr.len < 8) {
 148                 *err = WTAP_ERR_BAD_FILE;
 149                 *err_info = g_strdup_printf("packetlogger: record length %u is too small", pl_hdr.len);
 150                 return FALSE;
 151         }
 152         if (pl_hdr.len - 8 > WTAP_MAX_PACKET_SIZE) {
 153                 /*
 154                  * Probably a corrupt capture file; don't blow up trying
 155                  * to allocate space for an immensely-large packet.
 156                  */
 157                 *err = WTAP_ERR_BAD_FILE;
 158                 *err_info = g_strdup_printf("packetlogger: File has %u-byte packet, bigger than maximum of %u",
 159                     pl_hdr.len - 8, WTAP_MAX_PACKET_SIZE);
 160                 return FALSE;
 161         }
 162
 163         phdr->presence_flags = WTAP_HAS_TS;
 164
 165         phdr->len = pl_hdr.len - 8;
 166         phdr->caplen = pl_hdr.len - 8;
 167
 168         phdr->ts.secs = (time_t) (pl_hdr.ts >> 32);
 169         phdr->ts.nsecs = (int)((pl_hdr.ts & 0xFFFFFFFF) * 1000);
 170
 171         return wtap_read_packet_bytes(fh, buf, phdr->caplen, err, err_info);
 172 }