![Guy Harris](/assets/img/avatar_default.png)
same. Add to wiretap/pcap-common.c a routine to fill in the pseudo-header for ATM (by looking at the VPI, VCI, and packet data, and guessing) and Ethernet (setting the FCS length appropriately). Use it for both pcap and pcap-ng files. svn path=/trunk/; revision=38840
194 lines
4.8 KiB
C
194 lines
4.8 KiB
C
/* mime_file.c
|
|
*
|
|
* MIME file format decoder for the Wiretap library.
|
|
*
|
|
* This is for use with Wireshark dissectors that handle file
|
|
* formats (e.g., because they handle a particular MIME media type).
|
|
* It breaks the file into chunks of at most WTAP_MAX_PACKET_SIZE,
|
|
* each of which is reported as a packet, so that files larger than
|
|
* WTAP_MAX_PACKET_SIZE can be handled by reassembly.
|
|
*
|
|
* The "MIME file" dissector does the reassembly, and hands the result
|
|
* off to heuristic dissectors to try to identify the file's contents.
|
|
*
|
|
* $Id$
|
|
*
|
|
* Wiretap Library
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version 2
|
|
* of the License, or (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
|
|
*/
|
|
|
|
#ifdef HAVE_CONFIG_H
|
|
#include "config.h"
|
|
#endif
|
|
|
|
#ifdef HAVE_SYS_TYPES_H
|
|
#include <sys/types.h>
|
|
#endif
|
|
|
|
#ifdef HAVE_UNISTD_H
|
|
#include <unistd.h>
|
|
#endif
|
|
|
|
#include <errno.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <time.h>
|
|
|
|
#include "wtap-int.h"
|
|
#include "file_wrappers.h"
|
|
#include "buffer.h"
|
|
#include "mime_file.h"
|
|
|
|
typedef struct {
|
|
gboolean last_packet;
|
|
|
|
} mime_file_private_t;
|
|
|
|
typedef struct {
|
|
const guint8 *magic;
|
|
guint magic_len;
|
|
} mime_files_t;
|
|
|
|
/*
|
|
* Written by Marton Nemeth <nm127@freemail.hu>
|
|
* Copyright 2009 Marton Nemeth
|
|
* The JPEG and JFIF specification can be found at:
|
|
*
|
|
* http://www.jpeg.org/public/jfif.pdf
|
|
* http://www.w3.org/Graphics/JPEG/itu-t81.pdf
|
|
*/
|
|
static const guint8 jpeg_jfif_magic[] = { 0xFF, 0xD8, /* SOF */
|
|
0xFF /* start of the next marker */
|
|
};
|
|
|
|
static const mime_files_t magic_files[] = {
|
|
{ jpeg_jfif_magic, sizeof(jpeg_jfif_magic) }
|
|
};
|
|
|
|
#define N_MAGIC_TYPES (sizeof(magic_files) / sizeof(magic_files[0]))
|
|
|
|
static gboolean
|
|
mime_read(wtap *wth, int *err, gchar **err_info, gint64 *data_offset)
|
|
{
|
|
mime_file_private_t *priv = (mime_file_private_t *) wth->priv;
|
|
|
|
char _buf[WTAP_MAX_PACKET_SIZE];
|
|
guint8 *buf;
|
|
int packet_size;
|
|
|
|
if (priv->last_packet) {
|
|
*err = file_error(wth->fh, err_info);
|
|
return FALSE;
|
|
}
|
|
|
|
wth->phdr.ts.secs = (time_t) wth->data_offset;
|
|
wth->phdr.ts.nsecs = 0;
|
|
|
|
*data_offset = wth->data_offset;
|
|
|
|
/* try to read max WTAP_MAX_PACKET_SIZE bytes */
|
|
packet_size = file_read(_buf, sizeof(_buf), wth->fh);
|
|
|
|
if (packet_size <= 0) {
|
|
priv->last_packet = TRUE;
|
|
/* signal error for packet-mime-encap */
|
|
if (packet_size < 0)
|
|
wth->phdr.ts.nsecs = 1000000000;
|
|
|
|
wth->phdr.caplen = 0;
|
|
wth->phdr.len = 0;
|
|
return TRUE;
|
|
}
|
|
|
|
/* copy to wth frame buffer */
|
|
buffer_assure_space(wth->frame_buffer, packet_size);
|
|
buf = buffer_start_ptr(wth->frame_buffer);
|
|
memcpy(buf, _buf, packet_size);
|
|
|
|
wth->data_offset += packet_size;
|
|
wth->phdr.caplen = packet_size;
|
|
wth->phdr.len = packet_size;
|
|
return TRUE;
|
|
}
|
|
|
|
static gboolean
|
|
mime_seek_read(wtap *wth, gint64 seek_off, union wtap_pseudo_header *pseudo_header _U_, guint8 *pd, int length, int *err, gchar **err_info)
|
|
{
|
|
if (file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1) {
|
|
*err_info = NULL;
|
|
return FALSE;
|
|
}
|
|
|
|
wtap_file_read_expected_bytes(pd, length, wth->random_fh, err, err_info);
|
|
|
|
*err = 0;
|
|
*err_info = NULL;
|
|
return TRUE;
|
|
}
|
|
|
|
int
|
|
mime_file_open(wtap *wth, int *err, gchar **err_info)
|
|
{
|
|
char magic_buf[128]; /* increase buffer size when needed */
|
|
int bytes_read;
|
|
int ret;
|
|
guint i;
|
|
|
|
guint read_bytes = 0;
|
|
|
|
for (i = 0; i < N_MAGIC_TYPES; i++)
|
|
read_bytes = MAX(read_bytes, magic_files[i].magic_len);
|
|
|
|
read_bytes = MIN(read_bytes, sizeof(magic_buf));
|
|
bytes_read = file_read(magic_buf, read_bytes, wth->fh);
|
|
|
|
if (bytes_read > 0) {
|
|
gboolean found_file = FALSE;
|
|
/* guint file_ok; */
|
|
|
|
for (i = 0; i < N_MAGIC_TYPES; i++) {
|
|
if ((guint) bytes_read >= magic_files[i].magic_len && !memcmp(magic_buf, magic_files[i].magic, MIN(magic_files[i].magic_len, (guint) bytes_read))) {
|
|
if (!found_file) {
|
|
found_file = TRUE;
|
|
/* file_ok = i; */
|
|
} else
|
|
return 0; /* many files matched, bad file */
|
|
}
|
|
}
|
|
|
|
if (!found_file)
|
|
return 0;
|
|
|
|
if (file_seek(wth->fh, 0, SEEK_SET, err) == -1)
|
|
return -1;
|
|
|
|
wth->file_type = WTAP_FILE_MIME;
|
|
wth->file_encap = WTAP_ENCAP_MIME;
|
|
wth->tsprecision = WTAP_FILE_TSPREC_SEC;
|
|
wth->subtype_read = mime_read;
|
|
wth->subtype_seek_read = mime_seek_read;
|
|
wth->snapshot_length = 0;
|
|
ret = 1;
|
|
|
|
wth->priv = g_malloc0(sizeof(mime_file_private_t));
|
|
|
|
} else {
|
|
*err = file_error(wth->fh, err_info);
|
|
ret = -1;
|
|
}
|
|
return ret;
|
|
}
|
|
|