wireshark/wiretap/tnef.c
Guy Harris 6db77b000f Allow wtap_read() and wtap_seek_read() to return records other than packets.
Add a "record type" field to "struct wtap_pkthdr"; currently, it can be
REC_TYPE_PACKET, for a record containing a packet, or
REC_TYPE_FILE_TYPE_SPECIFIC, for records containing file-type-specific
data.

Modify code that reads packets to be able to handle non-packet records,
even if that just means ignoring them.

Rename some routines to indicate that they handle more than just
packets.

We don't yet have any libwiretap code that supplies records other than
REC_TYPE_PACKET or that supporting writing records other than
REC_TYPE_PACKET, or any code to support plugins for handling
REC_TYPE_FILE_TYPE_SPECIFIC records; this is just the first step for bug
8590.

Change-Id: Idb40b78f17c2c3aea72031bcd252abf9bc11c813
Reviewed-on: https://code.wireshark.org/review/1773
Reviewed-by: Guy Harris <guy@alum.mit.edu>
2014-05-24 18:31:25 +00:00

128 lines
3.4 KiB
C

/* tnef.c
*
* Transport-Neutral Encapsulation Format (TNEF) file reading
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "config.h"
#include <errno.h>
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#include "wtap-int.h"
#include "file_wrappers.h"
#include "buffer.h"
#include "tnef.h"
static gboolean tnef_read_file(wtap *wth, FILE_T fh, struct wtap_pkthdr *phdr,
Buffer *buf, int *err, gchar **err_info)
{
gint64 file_size;
int packet_size;
if ((file_size = wtap_file_size(wth, err)) == -1)
return FALSE;
if (file_size > WTAP_MAX_PACKET_SIZE) {
/*
* Probably a corrupt capture file; don't blow up trying
* to allocate space for an immensely-large packet.
*/
*err = WTAP_ERR_BAD_FILE;
*err_info = g_strdup_printf("tnef: File has %" G_GINT64_MODIFIER "d-byte packet, bigger than maximum of %u",
file_size, WTAP_MAX_PACKET_SIZE);
return FALSE;
}
packet_size = (int)file_size;
phdr->rec_type = REC_TYPE_PACKET;
phdr->presence_flags = 0; /* yes, we have no bananas^Wtime stamp */
phdr->caplen = packet_size;
phdr->len = packet_size;
phdr->ts.secs = 0;
phdr->ts.nsecs = 0;
return wtap_read_packet_bytes(fh, buf, packet_size, err, err_info);
}
static gboolean tnef_read(wtap *wth, int *err, gchar **err_info, gint64 *data_offset)
{
gint64 offset;
*err = 0;
offset = file_tell(wth->fh);
/* there is only ever one packet */
if (offset)
return FALSE;
*data_offset = offset;
return tnef_read_file(wth, wth->fh, &wth->phdr, wth->frame_buffer, err, err_info);
}
static gboolean tnef_seek_read(wtap *wth, gint64 seek_off,
struct wtap_pkthdr *phdr,
Buffer *buf, int *err, gchar **err_info)
{
/* there is only one packet */
if(seek_off > 0) {
*err = 0;
return FALSE;
}
if (file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1)
return FALSE;
return tnef_read_file(wth, wth->random_fh, phdr, buf, err, err_info);
}
int tnef_open(wtap *wth, int *err, gchar **err_info)
{
int bytes_read;
guint32 magic;
bytes_read = file_read(&magic, sizeof magic, wth->fh);
if (bytes_read != sizeof magic) {
*err = file_error(wth->fh, err_info);
return (*err != 0) ? -1 : 0;
}
if (GUINT32_TO_LE(magic) != TNEF_SIGNATURE)
/* Not a tnef file */
return 0;
/* seek back to the start of the file */
if (file_seek(wth->fh, 0, SEEK_SET, err) == -1)
return -1;
wth->file_type_subtype = WTAP_FILE_TYPE_SUBTYPE_TNEF;
wth->file_encap = WTAP_ENCAP_TNEF;
wth->snapshot_length = 0;
wth->subtype_read = tnef_read;
wth->subtype_seek_read = tnef_seek_read;
wth->tsprecision = WTAP_FILE_TSPREC_SEC;
return 1;
}