9d41c658fe
wtap_seek_read(). svn path=/trunk/; revision=54570
223 lines
6.4 KiB
C
223 lines
6.4 KiB
C
/* csids.c
|
|
*
|
|
* $Id$
|
|
*
|
|
* Copyright (c) 2000 by Mike Hall <mlh@io.com>
|
|
* Copyright (c) 2000 by Cisco Systems
|
|
*
|
|
* 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 "wtap-int.h"
|
|
#include "buffer.h"
|
|
#include "csids.h"
|
|
#include "file_wrappers.h"
|
|
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
|
|
/*
|
|
* This module reads the output from the Cisco Secure Intrusion Detection
|
|
* System iplogging facility. The term iplogging is misleading since this
|
|
* logger will only output TCP. There is no link layer information.
|
|
* Packet format is 4 byte timestamp (seconds since epoch), and a 4 byte size
|
|
* of data following for that packet.
|
|
*
|
|
* For a time there was an error in iplogging and the ip length, flags, and id
|
|
* were byteswapped. We will check for this and handle it before handing to
|
|
* wireshark.
|
|
*/
|
|
|
|
typedef struct {
|
|
gboolean byteswapped;
|
|
} csids_t;
|
|
|
|
static gboolean csids_read(wtap *wth, int *err, gchar **err_info,
|
|
gint64 *data_offset);
|
|
static gboolean csids_seek_read(wtap *wth, gint64 seek_off,
|
|
struct wtap_pkthdr *phdr, Buffer *buf, int *err, gchar **err_info);
|
|
static gboolean csids_read_packet(FILE_T fh, csids_t *csids,
|
|
struct wtap_pkthdr *phdr, Buffer *buf, int *err, gchar **err_info);
|
|
|
|
struct csids_header {
|
|
guint32 seconds; /* seconds since epoch */
|
|
guint16 zeropad; /* 2 byte zero'ed pads */
|
|
guint16 caplen; /* the capture length */
|
|
};
|
|
|
|
/* XXX - return -1 on I/O error and actually do something with 'err'. */
|
|
int csids_open(wtap *wth, int *err, gchar **err_info)
|
|
{
|
|
/* There is no file header. There is only a header for each packet
|
|
* so we read a packet header and compare the caplen with iplen. They
|
|
* should always be equal except with the weird byteswap version.
|
|
*
|
|
* THIS IS BROKEN-- anytime the caplen is 0x0101 or 0x0202 up to 0x0505
|
|
* this will byteswap it. I need to fix this. XXX --mlh
|
|
*/
|
|
|
|
int tmp,iplen,bytesRead;
|
|
|
|
gboolean byteswap = FALSE;
|
|
struct csids_header hdr;
|
|
csids_t *csids;
|
|
|
|
/* check the file to make sure it is a csids file. */
|
|
bytesRead = file_read( &hdr, sizeof( struct csids_header), wth->fh );
|
|
if( bytesRead != sizeof( struct csids_header) ) {
|
|
*err = file_error( wth->fh, err_info );
|
|
if( *err != 0 && *err != WTAP_ERR_SHORT_READ ) {
|
|
return -1;
|
|
}
|
|
return 0;
|
|
}
|
|
if( hdr.zeropad != 0 || hdr.caplen == 0 ) {
|
|
return 0;
|
|
}
|
|
hdr.seconds = pntoh32( &hdr.seconds );
|
|
hdr.caplen = pntoh16( &hdr.caplen );
|
|
bytesRead = file_read( &tmp, 2, wth->fh );
|
|
if( bytesRead != 2 ) {
|
|
*err = file_error( wth->fh, err_info );
|
|
if( *err != 0 && *err != WTAP_ERR_SHORT_READ ) {
|
|
return -1;
|
|
}
|
|
return 0;
|
|
}
|
|
bytesRead = file_read( &iplen, 2, wth->fh );
|
|
if( bytesRead != 2 ) {
|
|
*err = file_error( wth->fh, err_info );
|
|
if( *err != 0 && *err != WTAP_ERR_SHORT_READ ) {
|
|
return -1;
|
|
}
|
|
return 0;
|
|
}
|
|
iplen = pntoh16(&iplen);
|
|
|
|
if ( iplen == 0 )
|
|
return 0;
|
|
|
|
/* if iplen and hdr.caplen are equal, default to no byteswap. */
|
|
if( iplen > hdr.caplen ) {
|
|
/* maybe this is just a byteswapped version. the iplen ipflags */
|
|
/* and ipid are swapped. We cannot use the normal swaps because */
|
|
/* we don't know the host */
|
|
iplen = GUINT16_SWAP_LE_BE(iplen);
|
|
if( iplen <= hdr.caplen ) {
|
|
/* we know this format */
|
|
byteswap = TRUE;
|
|
} else {
|
|
/* don't know this one */
|
|
return 0;
|
|
}
|
|
} else {
|
|
byteswap = FALSE;
|
|
}
|
|
|
|
/* no file header. So reset the fh to 0 so we can read the first packet */
|
|
if (file_seek(wth->fh, 0, SEEK_SET, err) == -1)
|
|
return -1;
|
|
|
|
csids = (csids_t *)g_malloc(sizeof(csids_t));
|
|
wth->priv = (void *)csids;
|
|
csids->byteswapped = byteswap;
|
|
wth->file_encap = WTAP_ENCAP_RAW_IP;
|
|
wth->file_type_subtype = WTAP_FILE_TYPE_SUBTYPE_CSIDS;
|
|
wth->snapshot_length = 0; /* not known */
|
|
wth->subtype_read = csids_read;
|
|
wth->subtype_seek_read = csids_seek_read;
|
|
wth->tsprecision = WTAP_FILE_TSPREC_SEC;
|
|
|
|
return 1;
|
|
}
|
|
|
|
/* Find the next packet and parse it; called from wtap_read(). */
|
|
static gboolean csids_read(wtap *wth, int *err, gchar **err_info,
|
|
gint64 *data_offset)
|
|
{
|
|
csids_t *csids = (csids_t *)wth->priv;
|
|
|
|
*data_offset = file_tell(wth->fh);
|
|
|
|
return csids_read_packet( wth->fh, csids, &wth->phdr, wth->frame_buffer,
|
|
err, err_info );
|
|
}
|
|
|
|
/* Used to read packets in random-access fashion */
|
|
static gboolean
|
|
csids_seek_read(wtap *wth,
|
|
gint64 seek_off,
|
|
struct wtap_pkthdr *phdr,
|
|
Buffer *buf,
|
|
int *err,
|
|
gchar **err_info)
|
|
{
|
|
csids_t *csids = (csids_t *)wth->priv;
|
|
|
|
if( file_seek( wth->random_fh, seek_off, SEEK_SET, err ) == -1 )
|
|
return FALSE;
|
|
|
|
if( !csids_read_packet( wth->random_fh, csids, phdr, buf, err, err_info ) ) {
|
|
if( *err == 0 )
|
|
*err = WTAP_ERR_SHORT_READ;
|
|
return FALSE;
|
|
}
|
|
return TRUE;
|
|
}
|
|
|
|
static gboolean
|
|
csids_read_packet(FILE_T fh, csids_t *csids, struct wtap_pkthdr *phdr,
|
|
Buffer *buf, int *err, gchar **err_info)
|
|
{
|
|
struct csids_header hdr;
|
|
int bytesRead = 0;
|
|
guint8 *pd;
|
|
|
|
bytesRead = file_read( &hdr, sizeof( struct csids_header), fh );
|
|
if( bytesRead != sizeof( struct csids_header) ) {
|
|
*err = file_error( fh, err_info );
|
|
if (*err == 0 && bytesRead != 0)
|
|
*err = WTAP_ERR_SHORT_READ;
|
|
return FALSE;
|
|
}
|
|
hdr.seconds = pntoh32(&hdr.seconds);
|
|
hdr.caplen = pntoh16(&hdr.caplen);
|
|
|
|
phdr->presence_flags = WTAP_HAS_TS;
|
|
phdr->len = hdr.caplen;
|
|
phdr->caplen = hdr.caplen;
|
|
phdr->ts.secs = hdr.seconds;
|
|
phdr->ts.nsecs = 0;
|
|
|
|
if( !wtap_read_packet_bytes( fh, buf, phdr->caplen, err, err_info ) )
|
|
return FALSE;
|
|
|
|
pd = buffer_start_ptr( buf );
|
|
if( csids->byteswapped ) {
|
|
if( phdr->caplen >= 2 ) {
|
|
PBSWAP16(pd); /* the ip len */
|
|
if( phdr->caplen >= 4 ) {
|
|
PBSWAP16(pd+2); /* ip id */
|
|
if( phdr->caplen >= 6 )
|
|
PBSWAP16(pd+4); /* ip flags and fragoff */
|
|
}
|
|
}
|
|
}
|
|
|
|
return TRUE;
|
|
}
|