forked from osmocom/wireshark
![Guy Harris](/assets/img/avatar_default.png)
That makes them work as input to a mergecap that writes pcapng files. File types that don't have a single per-file encapsulation type need more work, with multiple fake IDBs, one for each packet encapsulation type seen in the file, unless we can generate real IDBs. Change-Id: I2859e4f7fb15ec0c0f31a4044dc15638e5db7826 Reviewed-on: https://code.wireshark.org/review/37983 Petri-Dish: Guy Harris <gharris@sonic.net> Tested-by: Petri Dish Buildbot Reviewed-by: Guy Harris <gharris@sonic.net>
308 lines
7.6 KiB
C
308 lines
7.6 KiB
C
/* i4btrace.c
|
|
*
|
|
* Wiretap Library
|
|
* Copyright (c) 1999 by Bert Driehuis <driehuis@playbeing.org>
|
|
*
|
|
* SPDX-License-Identifier: GPL-2.0-or-later
|
|
*/
|
|
|
|
#include "config.h"
|
|
|
|
#include <stdlib.h>
|
|
#include <errno.h>
|
|
#include <string.h>
|
|
#include "wtap-int.h"
|
|
#include "file_wrappers.h"
|
|
#include "i4b_trace.h"
|
|
#include "i4btrace.h"
|
|
|
|
typedef struct {
|
|
gboolean byte_swapped;
|
|
} i4btrace_t;
|
|
|
|
static gboolean i4btrace_read(wtap *wth, wtap_rec *rec, Buffer *buf,
|
|
int *err, gchar **err_info, gint64 *offset);
|
|
static gboolean i4btrace_seek_read(wtap *wth, gint64 seek_off,
|
|
wtap_rec *rec, Buffer *buf, int *err, gchar **err_info);
|
|
static int i4b_read_rec(wtap *wth, FILE_T fh, wtap_rec *rec,
|
|
Buffer *buf, int *err, gchar **err_info);
|
|
|
|
/*
|
|
* Byte-swap the header.
|
|
*/
|
|
#define I4B_BYTESWAP_HEADER(hdr) \
|
|
{ \
|
|
hdr.length = GUINT32_SWAP_LE_BE(hdr.length); \
|
|
hdr.unit = GUINT32_SWAP_LE_BE(hdr.unit); \
|
|
hdr.type = GUINT32_SWAP_LE_BE(hdr.type); \
|
|
hdr.dir = GUINT32_SWAP_LE_BE(hdr.dir); \
|
|
hdr.trunc = GUINT32_SWAP_LE_BE(hdr.trunc); \
|
|
hdr.count = GUINT32_SWAP_LE_BE(hdr.count); \
|
|
hdr.ts_sec = GUINT32_SWAP_LE_BE(hdr.ts_sec); \
|
|
hdr.ts_usec = GUINT32_SWAP_LE_BE(hdr.ts_usec); \
|
|
}
|
|
|
|
/*
|
|
* Test some fields in the header to see if they make sense.
|
|
*/
|
|
#define I4B_HDR_IS_OK(hdr) \
|
|
(!(hdr.length < sizeof(hdr) || \
|
|
hdr.length > 16384 || \
|
|
hdr.unit > 4 || \
|
|
hdr.type > TRC_CH_B2 || \
|
|
hdr.dir > FROM_NT || \
|
|
hdr.trunc > 2048 || \
|
|
hdr.ts_usec >= 1000000))
|
|
|
|
/*
|
|
* Number of packets to try reading.
|
|
*/
|
|
#define PACKETS_TO_CHECK 5
|
|
|
|
wtap_open_return_val i4btrace_open(wtap *wth, int *err, gchar **err_info)
|
|
{
|
|
i4b_trace_hdr_t hdr;
|
|
gboolean byte_swapped = FALSE;
|
|
i4btrace_t *i4btrace;
|
|
|
|
/* I4B trace files have no magic in the header... Sigh */
|
|
if (!wtap_read_bytes(wth->fh, &hdr, sizeof(hdr), err, err_info)) {
|
|
if (*err != WTAP_ERR_SHORT_READ)
|
|
return WTAP_OPEN_ERROR;
|
|
return WTAP_OPEN_NOT_MINE;
|
|
}
|
|
|
|
/* Silly heuristic... */
|
|
if (!I4B_HDR_IS_OK(hdr)) {
|
|
/*
|
|
* OK, try byte-swapping the header fields.
|
|
*/
|
|
I4B_BYTESWAP_HEADER(hdr);
|
|
if (!I4B_HDR_IS_OK(hdr)) {
|
|
/*
|
|
* It doesn't look valid in either byte order.
|
|
*/
|
|
return WTAP_OPEN_NOT_MINE;
|
|
}
|
|
|
|
/*
|
|
* It looks valid byte-swapped, so assume it's a
|
|
* trace written in the opposite byte order.
|
|
*/
|
|
byte_swapped = TRUE;
|
|
}
|
|
|
|
/*
|
|
* Now try to read past the packet bytes; if that fails with
|
|
* a short read, we don't fail, so that we can report
|
|
* the file as a truncated I4B file.
|
|
*/
|
|
if (!wtap_read_bytes(wth->fh, NULL, hdr.length - (guint32)sizeof(hdr),
|
|
err, err_info)) {
|
|
if (*err != WTAP_ERR_SHORT_READ)
|
|
return WTAP_OPEN_ERROR;
|
|
} else {
|
|
/*
|
|
* Now try reading a few more packets.
|
|
*/
|
|
for (int i = 1; i < PACKETS_TO_CHECK; i++) {
|
|
/*
|
|
* Read and check the file header; we've already
|
|
* decided whether this would be a byte-swapped file
|
|
* or not, so we swap iff we decided it was.
|
|
*/
|
|
if (!wtap_read_bytes_or_eof(wth->fh, &hdr, sizeof(hdr), err,
|
|
err_info)) {
|
|
if (*err == 0) {
|
|
/* EOF; no more packets to try. */
|
|
break;
|
|
}
|
|
if (*err != WTAP_ERR_SHORT_READ)
|
|
return WTAP_OPEN_ERROR;
|
|
return WTAP_OPEN_NOT_MINE;
|
|
}
|
|
|
|
if (byte_swapped)
|
|
I4B_BYTESWAP_HEADER(hdr);
|
|
if (!I4B_HDR_IS_OK(hdr)) {
|
|
/*
|
|
* It doesn't look valid.
|
|
*/
|
|
return WTAP_OPEN_NOT_MINE;
|
|
}
|
|
|
|
/*
|
|
* Now try to read past the packet bytes; if that
|
|
* fails with a short read, we don't fail, so that
|
|
* we can report the file as a truncated I4B file.
|
|
*/
|
|
if (!wtap_read_bytes(wth->fh, NULL,
|
|
hdr.length - (guint32)sizeof(hdr), err, err_info)) {
|
|
if (*err != WTAP_ERR_SHORT_READ)
|
|
return WTAP_OPEN_ERROR;
|
|
|
|
/*
|
|
* Probably a truncated file, so just quit.
|
|
*/
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (file_seek(wth->fh, 0, SEEK_SET, err) == -1)
|
|
return WTAP_OPEN_ERROR;
|
|
|
|
/* Get capture start time */
|
|
|
|
wth->file_type_subtype = WTAP_FILE_TYPE_SUBTYPE_I4BTRACE;
|
|
i4btrace = (i4btrace_t *)g_malloc(sizeof(i4btrace_t));
|
|
wth->priv = (void *)i4btrace;
|
|
wth->subtype_read = i4btrace_read;
|
|
wth->subtype_seek_read = i4btrace_seek_read;
|
|
wth->snapshot_length = 0; /* not known */
|
|
|
|
i4btrace->byte_swapped = byte_swapped;
|
|
|
|
wth->file_encap = WTAP_ENCAP_ISDN;
|
|
wth->file_tsprec = WTAP_TSPREC_USEC;
|
|
|
|
/*
|
|
* Add an IDB; we don't know how many interfaces were
|
|
* involved, so we just say one interface, about which
|
|
* we only know the link-layer type, snapshot length,
|
|
* and time stamp resolution.
|
|
*/
|
|
wtap_add_generated_idb(wth);
|
|
|
|
return WTAP_OPEN_MINE;
|
|
}
|
|
|
|
/* Read the next packet */
|
|
static gboolean i4btrace_read(wtap *wth, wtap_rec *rec, Buffer *buf,
|
|
int *err, gchar **err_info, gint64 *data_offset)
|
|
{
|
|
*data_offset = file_tell(wth->fh);
|
|
|
|
return i4b_read_rec(wth, wth->fh, rec, buf, err, err_info);
|
|
}
|
|
|
|
static gboolean
|
|
i4btrace_seek_read(wtap *wth, gint64 seek_off, wtap_rec *rec,
|
|
Buffer *buf, int *err, gchar **err_info)
|
|
{
|
|
if (file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1)
|
|
return FALSE;
|
|
|
|
if (!i4b_read_rec(wth, wth->random_fh, rec, buf, err, err_info)) {
|
|
/* Read error or EOF */
|
|
if (*err == 0) {
|
|
/* EOF means "short read" in random-access mode */
|
|
*err = WTAP_ERR_SHORT_READ;
|
|
}
|
|
return FALSE;
|
|
}
|
|
return TRUE;
|
|
}
|
|
|
|
static gboolean
|
|
i4b_read_rec(wtap *wth, FILE_T fh, wtap_rec *rec, Buffer *buf,
|
|
int *err, gchar **err_info)
|
|
{
|
|
i4btrace_t *i4btrace = (i4btrace_t *)wth->priv;
|
|
i4b_trace_hdr_t hdr;
|
|
guint32 length;
|
|
|
|
if (!wtap_read_bytes_or_eof(fh, &hdr, sizeof hdr, err, err_info))
|
|
return FALSE;
|
|
|
|
if (i4btrace->byte_swapped) {
|
|
/*
|
|
* Byte-swap the header.
|
|
*/
|
|
I4B_BYTESWAP_HEADER(hdr);
|
|
}
|
|
|
|
if (hdr.length < sizeof(hdr)) {
|
|
*err = WTAP_ERR_BAD_FILE; /* record length < header! */
|
|
*err_info = g_strdup_printf("i4btrace: record length %u < header length %lu",
|
|
hdr.length, (unsigned long)sizeof(hdr));
|
|
return FALSE;
|
|
}
|
|
length = hdr.length - (guint32)sizeof(hdr);
|
|
if (length > WTAP_MAX_PACKET_SIZE_STANDARD) {
|
|
/*
|
|
* 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("i4btrace: File has %u-byte packet, bigger than maximum of %u",
|
|
length, WTAP_MAX_PACKET_SIZE_STANDARD);
|
|
return FALSE;
|
|
}
|
|
|
|
rec->rec_type = REC_TYPE_PACKET;
|
|
rec->presence_flags = WTAP_HAS_TS;
|
|
|
|
rec->rec_header.packet_header.len = length;
|
|
rec->rec_header.packet_header.caplen = length;
|
|
|
|
rec->ts.secs = hdr.ts_sec;
|
|
rec->ts.nsecs = hdr.ts_usec * 1000;
|
|
|
|
switch (hdr.type) {
|
|
|
|
case TRC_CH_I:
|
|
/*
|
|
* XXX - what is it? It's probably not WTAP_ENCAP_NULL,
|
|
* as that means it has a 4-byte AF_ type as the
|
|
* encapsulation header.
|
|
*/
|
|
rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_NULL;
|
|
break;
|
|
|
|
case TRC_CH_D:
|
|
/*
|
|
* D channel, so it's LAPD; set "p2p.sent".
|
|
*/
|
|
rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_ISDN;
|
|
rec->rec_header.packet_header.pseudo_header.isdn.channel = 0;
|
|
break;
|
|
|
|
case TRC_CH_B1:
|
|
/*
|
|
* B channel 1.
|
|
*/
|
|
rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_ISDN;
|
|
rec->rec_header.packet_header.pseudo_header.isdn.channel = 1;
|
|
break;
|
|
|
|
case TRC_CH_B2:
|
|
/*
|
|
* B channel 2.
|
|
*/
|
|
rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_ISDN;
|
|
rec->rec_header.packet_header.pseudo_header.isdn.channel = 2;
|
|
break;
|
|
}
|
|
|
|
rec->rec_header.packet_header.pseudo_header.isdn.uton = (hdr.dir == FROM_TE);
|
|
|
|
/*
|
|
* Read the packet data.
|
|
*/
|
|
return wtap_read_packet_bytes(fh, buf, length, err, err_info);
|
|
}
|
|
|
|
/*
|
|
* Editor modelines - https://www.wireshark.org/tools/modelines.html
|
|
*
|
|
* Local variables:
|
|
* c-basic-offset: 8
|
|
* tab-width: 8
|
|
* indent-tabs-mode: t
|
|
* End:
|
|
*
|
|
* vi: set shiftwidth=8 tabstop=8 noexpandtab:
|
|
* :indentSize=8:tabSize=8:noTabs=false:
|
|
*/
|