![Guy Harris](/assets/img/avatar_default.png)
Add a missing entry in "encap_table[]" for Bluetooth H4, and fix some comments. svn path=/trunk/; revision=9157
1674 lines
48 KiB
C
1674 lines
48 KiB
C
/* libpcap.c
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*
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* $Id: libpcap.c,v 1.101 2003/12/03 22:40:39 guy Exp $
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*
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* Wiretap Library
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* Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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*/
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#ifdef HAVE_CONFIG_H
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#include "config.h"
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#endif
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#include <stdlib.h>
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#include <errno.h>
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#include "wtap-int.h"
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#include "file_wrappers.h"
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#include "buffer.h"
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#include "atm.h"
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#include "libpcap.h"
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#ifdef HAVE_PCAP_H
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# ifdef HAVE_SYS_TYPES_H
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# include <sys/types.h>
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# endif
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#include <pcap.h>
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#include "wtap-capture.h"
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#endif
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/*
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* The link-layer header on ATM packets.
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*/
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struct sunatm_hdr {
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guint8 flags; /* destination and traffic type */
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guint8 vpi; /* VPI */
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guint16 vci; /* VCI */
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};
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/* See source to the "libpcap" library for information on the "libpcap"
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file format. */
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/* On some systems, the FDDI MAC addresses are bit-swapped. */
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#if !defined(ultrix) && !defined(__alpha) && !defined(__bsdi__)
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#define BIT_SWAPPED_MAC_ADDRS
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#endif
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/* Try to read the first two records of the capture file. */
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typedef enum {
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THIS_FORMAT, /* the reads succeeded, assume it's this format */
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BAD_READ, /* the file is probably not valid */
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OTHER_FORMAT /* the file may be valid, but not in this format */
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} libpcap_try_t;
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static libpcap_try_t libpcap_try(wtap *wth, int *err);
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static gboolean libpcap_read(wtap *wth, int *err, long *data_offset);
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static gboolean libpcap_seek_read(wtap *wth, long seek_off,
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union wtap_pseudo_header *pseudo_header, guchar *pd, int length, int *err);
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static int libpcap_read_header(wtap *wth, int *err,
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struct pcaprec_ss990915_hdr *hdr, gboolean silent);
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static void adjust_header(wtap *wth, struct pcaprec_hdr *hdr);
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static void libpcap_get_atm_pseudoheader(const struct sunatm_hdr *atm_phdr,
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union wtap_pseudo_header *pseudo_header);
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static gboolean libpcap_read_atm_pseudoheader(FILE_T fh,
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union wtap_pseudo_header *pseudo_header, int *err);
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static gboolean libpcap_read_rec_data(FILE_T fh, guchar *pd, int length,
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int *err);
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static void libpcap_close(wtap *wth);
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static gboolean libpcap_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
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const union wtap_pseudo_header *pseudo_header, const guchar *pd, int *err);
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/*
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* Either LBL NRG wasn't an adequate central registry (e.g., because of
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* the slow rate of releases from them), or nobody bothered using them
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* as a central registry, as many different groups have patched libpcap
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* (and BPF, on the BSDs) to add new encapsulation types, and have ended
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* up using the same DLT_ values for different encapsulation types.
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*
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* For those numerical encapsulation type values that everybody uses for
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* the same encapsulation type (which inclues those that some platforms
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* specify different DLT_ names for but don't appear to use), we map
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* those values to the appropriate Wiretap values.
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*
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* For those numerical encapsulation type values that different libpcap
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* variants use for different encapsulation types, we check what
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* <pcap.h> defined to determine how to interpret them, so that we
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* interpret them the way the libpcap with which we're building
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* Ethereal/Wiretap interprets them (which, if it doesn't support
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* them at all, means we don't support them either - any capture files
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* using them are foreign, and we don't hazard a guess as to which
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* platform they came from; we could, I guess, choose the most likely
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* platform).
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*
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* Note: if you need a new encapsulation type for libpcap files, do
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* *N*O*T* use *ANY* of the values listed here! I.e., do *NOT*
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* add a new encapsulation type by changing an existing entry;
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* leave the existing entries alone.
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*
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* Instead, send mail to tcpdump-workers@tcpdump.org, asking for a new
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* DLT_ value, and specifying the purpose of the new value. When you
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* get the new DLT_ value, use that numerical value in the "dlt_value"
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* field of "pcap_to_wtap_map[]".
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*/
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static const struct {
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int dlt_value;
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int wtap_encap_value;
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} pcap_to_wtap_map[] = {
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/*
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* These are the values that are almost certainly the same
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* in all libpcaps (I've yet to find one where the values
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* in question are used for some purpose other than the
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* one below, but...), and that Wiretap and Ethereal
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* currently support.
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*/
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{ 0, WTAP_ENCAP_NULL }, /* null encapsulation */
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{ 1, WTAP_ENCAP_ETHERNET },
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{ 6, WTAP_ENCAP_TOKEN_RING }, /* IEEE 802 Networks - assume token ring */
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{ 7, WTAP_ENCAP_ARCNET },
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{ 8, WTAP_ENCAP_SLIP },
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{ 9, WTAP_ENCAP_PPP },
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#ifdef BIT_SWAPPED_MAC_ADDRS
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{ 10, WTAP_ENCAP_FDDI_BITSWAPPED },
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#else
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{ 10, WTAP_ENCAP_FDDI },
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#endif
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/*
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* 50 is DLT_PPP_SERIAL in NetBSD; it appears that DLT_PPP
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* on BSD (at least according to standard tcpdump) has, as
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* the first octet, an indication of whether the packet was
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* transmitted or received (rather than having the standard
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* PPP address value of 0xff), but that DLT_PPP_SERIAL puts
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* a real live PPP header there, or perhaps a Cisco PPP header
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* as per section 4.3.1 of RFC 1547 (implementations of this
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* exist in various BSDs in "sys/net/if_spppsubr.c", and
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* I think also exist either in standard Linux or in
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* various Linux patches; the implementations show how to handle
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* Cisco keepalive packets).
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*
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* However, I don't see any obvious place in FreeBSD "if_ppp.c"
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* where anything other than the standard PPP header would be
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* passed up. I see some stuff that sets the first octet
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* to 0 for incoming and 1 for outgoing packets before applying
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* a BPF filter to see whether to drop packets whose protocol
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* field has the 0x8000 bit set, i.e. network control protocols -
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* those are handed up to userland - but that code puts the
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* address field back before passing the packet up.
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*
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* I also don't see anything immediately obvious that munges
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* the address field for sync PPP, either.
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*
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* Ethereal currently assumes that if the first octet of a
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* PPP frame is 0xFF, it's the address field and is followed
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* by a control field and a 2-byte protocol, otherwise the
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* address and control fields are absent and the frame begins
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* with a protocol field. If we ever see a BSD/OS PPP
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* capture, we'll have to handle it differently, and we may
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* have to handle standard BSD captures differently if, in fact,
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* they don't have 0xff 0x03 as the first two bytes - but, as per
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* the two paragraphs preceding this, it's not clear that
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* the address field *is* munged into an incoming/outgoing
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* field when the packet is handed to the BPF device.
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*
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* For now, we just map DLT_PPP_SERIAL to WTAP_ENCAP_PPP, as
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* we treat WTAP_ENCAP_PPP packets as if those beginning with
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* 0xff have the standard RFC 1662 "PPP in HDLC-like Framing"
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* 0xff 0x03 address/control header, and DLT_PPP_SERIAL frames
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* appear to contain that unless they're Cisco frames (if we
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* ever see a capture with them, we'd need to implement the
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* RFC 1547 stuff, and the keepalive protocol stuff).
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*
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* We may have to distinguish between "PPP where if it doesn't
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* begin with 0xff there's no HDLC encapsulation and the frame
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* begins with the protocol field" (which is how we handle
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* WTAP_ENCAP_PPP now) and "PPP where there's either HDLC
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* encapsulation or Cisco PPP" (which is what DLT_PPP_SERIAL
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* is) at some point.
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*
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* XXX - NetBSD has DLT_HDLC, which appears to be used for
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* Cisco HDLC. Ideally, they should use DLT_PPP_SERIAL
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* only for real live HDLC-encapsulated PPP, not for Cisco
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* HDLC.
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*/
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{ 50, WTAP_ENCAP_PPP },
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/*
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* These are the values that libpcap 0.5 and later use in
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* capture file headers, in an attempt to work around the
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* confusion decried above, and that Wiretap and Ethereal
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* currently support.
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*/
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{ 100, WTAP_ENCAP_ATM_RFC1483 },
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{ 101, WTAP_ENCAP_RAW_IP },
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#if 0
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/*
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* More values used by libpcap 0.5 as DLT_ values and used by the
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* current CVS version of libpcap in capture file headers.
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* They are not yet handled in Ethereal.
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* If we get a capture that contains them, we'll implement them.
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*/
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{ 102, WTAP_ENCAP_SLIP_BSDOS },
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{ 103, WTAP_ENCAP_PPP_BSDOS },
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#endif
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/*
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* These ones are handled in Ethereal, though.
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*/
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{ 104, WTAP_ENCAP_CHDLC }, /* Cisco HDLC */
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{ 105, WTAP_ENCAP_IEEE_802_11 }, /* IEEE 802.11 */
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{ 106, WTAP_ENCAP_LINUX_ATM_CLIP },
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{ 107, WTAP_ENCAP_FRELAY }, /* Frame Relay */
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{ 108, WTAP_ENCAP_NULL }, /* OpenBSD loopback */
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{ 109, WTAP_ENCAP_ENC }, /* OpenBSD IPSEC enc */
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#if 0
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{ 110, WTAP_ENCAP_LANE_802_3 },/* ATM LANE 802.3 */
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{ 111, WTAP_ENCAP_HIPPI }, /* NetBSD HIPPI */
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#endif
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{ 112, WTAP_ENCAP_CHDLC }, /* NetBSD HDLC framing */
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/*
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* Linux "cooked mode" captures, used by the current CVS version
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* of libpcap.
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*/
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{ 113, WTAP_ENCAP_SLL }, /* Linux cooked capture */
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{ 114, WTAP_ENCAP_LOCALTALK }, /* Localtalk */
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/*
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* The tcpdump.org version of libpcap uses 117, rather than 17,
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* for OpenBSD packet filter logging, so as to avoid conflicting
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* with DLT_LANE8023 in SuSE 6.3 libpcap.
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*/
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{ 117, WTAP_ENCAP_PFLOG },
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{ 118, WTAP_ENCAP_CISCO_IOS },
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{ 119, WTAP_ENCAP_PRISM_HEADER }, /* Prism monitor mode hdr */
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{ 121, WTAP_ENCAP_HHDLC }, /* HiPath HDLC */
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{ 122, WTAP_ENCAP_IP_OVER_FC }, /* RFC 2625 IP-over-FC */
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{ 123, WTAP_ENCAP_ATM_PDUS }, /* SunATM */
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{ 127, WTAP_ENCAP_WLAN_HEADER }, /* 802.11 plus WLAN header */
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{ 128, WTAP_ENCAP_TZSP }, /* Tazmen Sniffer Protocol */
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{ 129, WTAP_ENCAP_ARCNET_LINUX },
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/*
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* Values 130 thorugh 137 are reserved for use in Juniper
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* hardware.
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*
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* 138 is reserved for Apple IP-over-IEEE 1394.
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*/
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{ 140, WTAP_ENCAP_MTP2 },
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{ 141, WTAP_ENCAP_MTP3 },
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/*
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* To repeat:
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*
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* If you need a new encapsulation type for libpcap files, do
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* *N*O*T* use *ANY* of the values listed here! I.e., do *NOT*
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* add a new encapsulation type by changing an existing entry;
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* leave the existing entries alone.
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*
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* Instead, send mail to tcpdump-workers@tcpdump.org, asking for
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* a new DLT_ value, and specifying the purpose of the new value.
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* When you get the new DLT_ value, use that numerical value in
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* the "dlt_value" field of "pcap_to_wtap_map[]".
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*/
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/*
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* The following are entries for libpcap type values that have
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* different meanings on different OSes.
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*
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* We put these *after* the entries for the platform-independent
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* libpcap type values for those Wiretap encapsulation types, so
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* that Ethereal chooses the platform-independent libpcap type
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* value for those encapsulatioin types, not the platform-dependent
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* one.
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*/
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/*
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* 11 is DLT_ATM_RFC1483 on most platforms; the only libpcaps I've
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* seen that define anything other than DLT_ATM_RFC1483 as 11 are
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* the BSD/OS one, which defines DLT_FR as 11, and libpcap 0.5,
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* which define it as 100, mapping the kernel's value to 100, in
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* an attempt to hide the different values used on different
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* platforms.
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*
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* If this is a platform where DLT_FR is defined as 11, we
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* don't handle 11 at all; otherwise, we handle it as
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* DLT_ATM_RFC1483 (this means we'd misinterpret Frame Relay
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* captures from BSD/OS if running on platforms other than BSD/OS,
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* but
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*
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* 1) we don't yet support DLT_FR
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*
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* and
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*
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* 2) nothing short of a heuristic would let us interpret
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* them correctly).
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*/
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#if defined(DLT_FR) && (DLT_FR == 11)
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{ 11, WTAP_ENCAP_FRELAY },
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#else
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{ 11, WTAP_ENCAP_ATM_RFC1483 },
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#endif
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/*
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* 12 is DLT_RAW on most platforms, but it's DLT_C_HDLC on
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* BSD/OS, and DLT_LOOP on OpenBSD.
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*
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* We don't yet handle DLT_C_HDLC, but we can handle DLT_LOOP
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* (it's just like DLT_NULL, only with the AF_ value in network
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* rather than host byte order - Ethereal figures out the
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* byte order from the data, so we don't care what byte order
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* it's in), so if DLT_LOOP is defined as 12, interpret 12
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* as WTAP_ENCAP_NULL, otherwise, unless DLT_C_HDLC is defined
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* as 12, interpret it as WTAP_ENCAP_RAW_IP.
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*/
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#if defined(DLT_LOOP) && (DLT_LOOP == 12)
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{ 12, WTAP_ENCAP_NULL },
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#elif defined(DLT_C_HDLC) && (DLT_C_HDLC == 12)
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/*
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* Put entry for Cisco HDLC here.
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* XXX - is this just WTAP_ENCAP_CHDLC, i.e. does the frame
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* start with a 4-byte Cisco HDLC header?
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*/
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#else
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{ 12, WTAP_ENCAP_RAW_IP },
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#endif
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/*
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* 13 is DLT_SLIP_BSDOS on FreeBSD and NetBSD, but those OSes
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* don't actually generate it. I infer that BSD/OS translates
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* DLT_SLIP from the kernel BPF code to DLT_SLIP_BSDOS in
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* libpcap, as the BSD/OS link-layer header is different;
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* however, in BSD/OS, DLT_SLIP_BSDOS is 15.
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*
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* From this, I infer that there's no point in handling 13
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* as DLT_SLIP_BSDOS.
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*
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* 13 is DLT_ATM_RFC1483 on BSD/OS.
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*
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* 13 is DLT_ENC in OpenBSD, which is, I suspect, some kind
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* of decrypted IPSEC traffic.
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*/
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#if defined(DLT_ATM_RFC1483) && (DLT_ATM_RFC1483 == 13)
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{ 13, WTAP_ENCAP_ATM_RFC1483 },
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#elif defined(DLT_ENC) && (DLT_ENC == 13)
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{ 13, WTAP_ENCAP_ENC },
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#endif
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/*
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* 14 is DLT_PPP_BSDOS on FreeBSD and NetBSD, but those OSes
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* don't actually generate it. I infer that BSD/OS translates
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* DLT_PPP from the kernel BPF code to DLT_PPP_BSDOS in
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* libpcap, as the BSD/OS link-layer header is different;
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* however, in BSD/OS, DLT_PPP_BSDOS is 16.
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*
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* From this, I infer that there's no point in handling 14
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* as DLT_PPP_BSDOS.
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*
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* 14 is DLT_RAW on BSD/OS and OpenBSD.
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*/
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{ 14, WTAP_ENCAP_RAW_IP },
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/*
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* 15 is:
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*
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* DLT_SLIP_BSDOS on BSD/OS;
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*
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* DLT_HIPPI on NetBSD;
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*
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* DLT_LANE8023 with Alexey Kuznetzov's patches for
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* Linux libpcap;
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*
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* DLT_I4L_RAWIP with the ISDN4Linux patches for libpcap
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* (and on SuSE 6.3);
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*
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* but we don't currently handle any of those.
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*/
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/*
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* 16 is:
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*
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* DLT_PPP_BSDOS on BSD/OS;
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*
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* DLT_HDLC on NetBSD (Cisco HDLC);
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*
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* DLT_CIP with Alexey Kuznetzov's patches for
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* Linux libpcap - this is WTAP_ENCAP_LINUX_ATM_CLIP;
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*
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* DLT_I4L_IP with the ISDN4Linux patches for libpcap
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* (and on SuSE 6.3).
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*/
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#if defined(DLT_CIP) && (DLT_CIP == 16)
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{ 16, WTAP_ENCAP_LINUX_ATM_CLIP },
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#endif
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#if defined(DLT_HDLC) && (DLT_HDLC == 16)
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{ 16, WTAP_ENCAP_CHDLC },
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#endif
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/*
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* 17 is DLT_LANE8023 in SuSE 6.3 libpcap; we don't currently
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* handle it.
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* It is also used as the PF (Packet Filter) logging format beginning
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* with OpenBSD 3.0; we use 17 for PF logs unless DLT_LANE8023 is
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* defined with the value 17.
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*/
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#if !defined(DLT_LANE8023) || (DLT_LANE8023 != 17)
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{ 17, WTAP_ENCAP_OLD_PFLOG },
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#endif
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/*
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* 18 is DLT_CIP in SuSE 6.3 libpcap; if it's the same as the
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* DLT_CIP of 16 that the Alexey Kuznetzov patches for
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* libpcap/tcpdump define, it's WTAP_ENCAP_LINUX_ATM_CLIP.
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* I've not found any libpcap that uses it for any other purpose -
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* hopefully nobody will do so in the future.
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*/
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{ 18, WTAP_ENCAP_LINUX_ATM_CLIP },
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/*
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* 19 is DLT_ATM_CLIP in the libpcap/tcpdump patches in the
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* recent versions I've seen of the Linux ATM distribution;
|
|
* I've not yet found any libpcap that uses it for any other
|
|
* purpose - hopefully nobody will do so in the future.
|
|
*/
|
|
{ 19, WTAP_ENCAP_LINUX_ATM_CLIP },
|
|
|
|
/*
|
|
* To repeat:
|
|
*
|
|
* If you need a new encapsulation type for libpcap files, do
|
|
* *N*O*T* use *ANY* of the values listed here! I.e., do *NOT*
|
|
* add a new encapsulation type by changing an existing entry;
|
|
* leave the existing entries alone.
|
|
*
|
|
* Instead, send mail to tcpdump-workers@tcpdump.org, asking for
|
|
* a new DLT_ value, and specifying the purpose of the new value.
|
|
* When you get the new DLT_ value, use that numerical value in
|
|
* the "dlt_value" field of "pcap_to_wtap_map[]".
|
|
*/
|
|
|
|
};
|
|
#define NUM_PCAP_ENCAPS (sizeof pcap_to_wtap_map / sizeof pcap_to_wtap_map[0])
|
|
|
|
int wtap_pcap_encap_to_wtap_encap(int encap)
|
|
{
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < NUM_PCAP_ENCAPS; i++) {
|
|
if (pcap_to_wtap_map[i].dlt_value == encap)
|
|
return pcap_to_wtap_map[i].wtap_encap_value;
|
|
}
|
|
return WTAP_ENCAP_UNKNOWN;
|
|
}
|
|
|
|
|
|
int libpcap_open(wtap *wth, int *err)
|
|
{
|
|
int bytes_read;
|
|
guint32 magic;
|
|
struct pcap_hdr hdr;
|
|
gboolean byte_swapped;
|
|
gboolean modified;
|
|
gboolean aix;
|
|
int file_encap;
|
|
|
|
/* Read in the number that should be at the start of a "libpcap" file */
|
|
errno = WTAP_ERR_CANT_READ;
|
|
bytes_read = file_read(&magic, 1, sizeof magic, wth->fh);
|
|
if (bytes_read != sizeof magic) {
|
|
*err = file_error(wth->fh);
|
|
if (*err != 0)
|
|
return -1;
|
|
return 0;
|
|
}
|
|
wth->data_offset += sizeof magic;
|
|
|
|
switch (magic) {
|
|
|
|
case PCAP_MAGIC:
|
|
/* Host that wrote it has our byte order, and was running
|
|
a program using either standard or ss990417 libpcap. */
|
|
byte_swapped = FALSE;
|
|
modified = FALSE;
|
|
break;
|
|
|
|
case PCAP_MODIFIED_MAGIC:
|
|
/* Host that wrote it has our byte order, and was running
|
|
a program using either ss990915 or ss991029 libpcap. */
|
|
byte_swapped = FALSE;
|
|
modified = TRUE;
|
|
break;
|
|
|
|
case PCAP_SWAPPED_MAGIC:
|
|
/* Host that wrote it has a byte order opposite to ours,
|
|
and was running a program using either standard or
|
|
ss990417 libpcap. */
|
|
byte_swapped = TRUE;
|
|
modified = FALSE;
|
|
break;
|
|
|
|
case PCAP_SWAPPED_MODIFIED_MAGIC:
|
|
/* Host that wrote it out has a byte order opposite to
|
|
ours, and was running a program using either ss990915
|
|
or ss991029 libpcap. */
|
|
byte_swapped = TRUE;
|
|
modified = TRUE;
|
|
break;
|
|
|
|
default:
|
|
/* Not a "libpcap" type we know about. */
|
|
return 0;
|
|
}
|
|
|
|
/* Read the rest of the header. */
|
|
errno = WTAP_ERR_CANT_READ;
|
|
bytes_read = file_read(&hdr, 1, sizeof hdr, wth->fh);
|
|
if (bytes_read != sizeof hdr) {
|
|
*err = file_error(wth->fh);
|
|
if (*err != 0)
|
|
return -1;
|
|
return 0;
|
|
}
|
|
wth->data_offset += sizeof hdr;
|
|
|
|
if (byte_swapped) {
|
|
/* Byte-swap the header fields about which we care. */
|
|
hdr.version_major = BSWAP16(hdr.version_major);
|
|
hdr.version_minor = BSWAP16(hdr.version_minor);
|
|
hdr.snaplen = BSWAP32(hdr.snaplen);
|
|
hdr.network = BSWAP32(hdr.network);
|
|
}
|
|
if (hdr.version_major < 2) {
|
|
/* We only support version 2.0 and later. */
|
|
g_message("pcap: major version %u unsupported",
|
|
hdr.version_major);
|
|
*err = WTAP_ERR_UNSUPPORTED;
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* AIX's non-standard tcpdump uses a minor version number of 2.
|
|
* Unfortunately, older versions of libpcap might have used
|
|
* that as well.
|
|
*
|
|
* The AIX libpcap uses RFC 1573 ifType values rather than
|
|
* DLT_ values in the header; the ifType values for LAN devices
|
|
* are:
|
|
*
|
|
* Ethernet 6
|
|
* Token Ring 9
|
|
* FDDI 15
|
|
*
|
|
* which correspond to DLT_IEEE802 (used for Token Ring),
|
|
* DLT_PPP, and DLT_SLIP_BSDOS, respectively. The ifType value
|
|
* for a loopback interface is 24, which currently isn't
|
|
* used by any version of libpcap I know about (and, as
|
|
* tcpdump.org are assigning DLT_ values above 100, and
|
|
* NetBSD started assigning values starting at 50, and
|
|
* the values chosen by other libpcaps appear to stop at
|
|
* 19, it's probably not going to be used by any libpcap
|
|
* in the future).
|
|
*
|
|
* We shall assume that if the minor version number is 2, and
|
|
* the network type is 6, 9, 15, or 24, that it's AIX libpcap.
|
|
*
|
|
* I'm assuming those older versions of libpcap didn't
|
|
* use DLT_IEEE802 for Token Ring, and didn't use DLT_SLIP_BSDOS
|
|
* as that came later. It may have used DLT_PPP, however, in
|
|
* which case we're out of luck; we assume it's Token Ring
|
|
* in AIX libpcap rather than PPP in standard libpcap, as
|
|
* you're probably more likely to be handing an AIX libpcap
|
|
* token-ring capture than an old (pre-libpcap 0.4) PPP capture
|
|
* to Ethereal.
|
|
*/
|
|
aix = FALSE; /* assume it's not AIX */
|
|
if (hdr.version_major == 2 && hdr.version_minor == 2) {
|
|
switch (hdr.network) {
|
|
|
|
case 6:
|
|
hdr.network = 1; /* DLT_EN10MB, Ethernet */
|
|
aix = TRUE;
|
|
break;
|
|
|
|
case 9:
|
|
hdr.network = 6; /* DLT_IEEE802, Token Ring */
|
|
aix = TRUE;
|
|
break;
|
|
|
|
case 15:
|
|
hdr.network = 10; /* DLT_FDDI, FDDI */
|
|
aix = TRUE;
|
|
break;
|
|
|
|
case 24:
|
|
hdr.network = 0; /* DLT_NULL, loopback */
|
|
aix = TRUE;
|
|
break;
|
|
}
|
|
}
|
|
file_encap = wtap_pcap_encap_to_wtap_encap(hdr.network);
|
|
if (file_encap == WTAP_ENCAP_UNKNOWN) {
|
|
g_message("pcap: network type %u unknown or unsupported",
|
|
hdr.network);
|
|
*err = WTAP_ERR_UNSUPPORTED_ENCAP;
|
|
return -1;
|
|
}
|
|
|
|
/* This is a libpcap file */
|
|
wth->capture.pcap = g_malloc(sizeof(libpcap_t));
|
|
wth->capture.pcap->byte_swapped = byte_swapped;
|
|
wth->capture.pcap->version_major = hdr.version_major;
|
|
wth->capture.pcap->version_minor = hdr.version_minor;
|
|
wth->subtype_read = libpcap_read;
|
|
wth->subtype_seek_read = libpcap_seek_read;
|
|
wth->subtype_close = libpcap_close;
|
|
wth->file_encap = file_encap;
|
|
wth->snapshot_length = hdr.snaplen;
|
|
|
|
/* In file format version 2.3, the order of the "incl_len" and
|
|
"orig_len" fields in the per-packet header was reversed,
|
|
in order to match the BPF header layout.
|
|
|
|
Therefore, in files with versions prior to that, we must swap
|
|
those two fields.
|
|
|
|
Unfortunately, some files were, according to a comment in the
|
|
"libpcap" source, written with version 2.3 in their headers
|
|
but without the interchanged fields, so if "incl_len" is
|
|
greater than "orig_len" - which would make no sense - we
|
|
assume that we need to swap them in version 2.3 files
|
|
as well.
|
|
|
|
In addition, DG/UX's tcpdump uses version 543.0, and writes
|
|
the two fields in the pre-2.3 order. */
|
|
switch (hdr.version_major) {
|
|
|
|
case 2:
|
|
if (hdr.version_minor < 3)
|
|
wth->capture.pcap->lengths_swapped = SWAPPED;
|
|
else if (hdr.version_minor == 3)
|
|
wth->capture.pcap->lengths_swapped = MAYBE_SWAPPED;
|
|
else
|
|
wth->capture.pcap->lengths_swapped = NOT_SWAPPED;
|
|
break;
|
|
|
|
case 543:
|
|
wth->capture.pcap->lengths_swapped = SWAPPED;
|
|
break;
|
|
|
|
default:
|
|
wth->capture.pcap->lengths_swapped = NOT_SWAPPED;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Is this AIX format?
|
|
*/
|
|
if (aix) {
|
|
/*
|
|
* Yes. Skip all the tests for other mutant formats.
|
|
*/
|
|
wth->file_type = WTAP_FILE_PCAP_AIX;
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* No. Let's look at the header for the first record,
|
|
* and see if, interpreting it as a standard header (if the
|
|
* magic number was standard) or a modified header (if the
|
|
* magic number was modified), the position where it says the
|
|
* header for the *second* record is contains a corrupted header.
|
|
*
|
|
* If so, then:
|
|
*
|
|
* If this file had the standard magic number, it may be
|
|
* an ss990417 capture file - in that version of Alexey's
|
|
* patch, the packet header format was changed but the
|
|
* magic number wasn't, and, alas, Red Hat appear to have
|
|
* picked up that version of the patch for RH 6.1, meaning
|
|
* RH 6.1 has a tcpdump that writes out files that can't
|
|
* be read by any software that expects non-modified headers
|
|
* if the magic number isn't the modified magic number (e.g.,
|
|
* any normal version of tcpdump, and Ethereal if we don't
|
|
* do this gross heuristic).
|
|
*
|
|
* If this file had the modified magic number, it may be
|
|
* an ss990915 capture file - in that version of Alexey's
|
|
* patch, the magic number was changed, but the record
|
|
* header had some extra fields, and, alas, SuSE appear
|
|
* to have picked up that version of the patch for SuSE
|
|
* 6.3, meaning that programs expecting the standard per-
|
|
* packet header in captures with the modified magic number
|
|
* can't read dumps from its tcpdump.
|
|
*
|
|
* Oh, and if it has the standard magic number, it might, instead,
|
|
* be a Nokia libpcap file, so we may need to try that if
|
|
* neither normal nor ss990417 headers work.
|
|
*/
|
|
if (modified) {
|
|
/*
|
|
* Well, we have the magic number from Alexey's
|
|
* later two patches.
|
|
*
|
|
* Try ss991029, the last of his patches, first.
|
|
*/
|
|
wth->file_type = WTAP_FILE_PCAP_SS991029;
|
|
switch (libpcap_try(wth, err)) {
|
|
|
|
case BAD_READ:
|
|
/*
|
|
* Well, we couldn't even read it.
|
|
* Give up.
|
|
*/
|
|
g_free(wth->capture.pcap);
|
|
return -1;
|
|
|
|
case THIS_FORMAT:
|
|
/*
|
|
* Well, it looks as if it might be 991029.
|
|
* Put the seek pointer back, and return success.
|
|
*/
|
|
if (file_seek(wth->fh, wth->data_offset, SEEK_SET, err) == -1) {
|
|
g_free(wth->capture.pcap);
|
|
return -1;
|
|
}
|
|
return 1;
|
|
|
|
case OTHER_FORMAT:
|
|
/*
|
|
* Try the next format.
|
|
*/
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Well, it's not completely unreadable,
|
|
* but it's not ss991029. Try ss990915;
|
|
* there are no other types to try after that,
|
|
* so we put the seek pointer back and treat
|
|
* it as 990915.
|
|
*/
|
|
wth->file_type = WTAP_FILE_PCAP_SS990915;
|
|
if (file_seek(wth->fh, wth->data_offset, SEEK_SET, err) == -1) {
|
|
g_free(wth->capture.pcap);
|
|
return -1;
|
|
}
|
|
} else {
|
|
/*
|
|
* Well, we have the standard magic number.
|
|
*
|
|
* Try the standard format first.
|
|
*/
|
|
wth->file_type = WTAP_FILE_PCAP;
|
|
switch (libpcap_try(wth, err)) {
|
|
|
|
case BAD_READ:
|
|
/*
|
|
* Well, we couldn't even read it.
|
|
* Give up.
|
|
*/
|
|
g_free(wth->capture.pcap);
|
|
return -1;
|
|
|
|
case THIS_FORMAT:
|
|
/*
|
|
* Well, it looks as if it might be a standard
|
|
* libpcap file.
|
|
* Put the seek pointer back, and return success.
|
|
*/
|
|
if (file_seek(wth->fh, wth->data_offset, SEEK_SET, err) == -1) {
|
|
g_free(wth->capture.pcap);
|
|
return -1;
|
|
}
|
|
return 1;
|
|
|
|
case OTHER_FORMAT:
|
|
/*
|
|
* Try the next format.
|
|
*/
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Well, it's not completely unreadable, but it's not
|
|
* a standard file. Put the seek pointer back and try
|
|
* ss990417.
|
|
*/
|
|
wth->file_type = WTAP_FILE_PCAP_SS990417;
|
|
if (file_seek(wth->fh, wth->data_offset, SEEK_SET, err) == -1) {
|
|
g_free(wth->capture.pcap);
|
|
return -1;
|
|
}
|
|
switch (libpcap_try(wth, err)) {
|
|
|
|
case BAD_READ:
|
|
/*
|
|
* Well, we couldn't even read it.
|
|
* Give up.
|
|
*/
|
|
g_free(wth->capture.pcap);
|
|
return -1;
|
|
|
|
case THIS_FORMAT:
|
|
/*
|
|
* Well, it looks as if it might be ss990417.
|
|
* Put the seek pointer back, and return success.
|
|
*/
|
|
if (file_seek(wth->fh, wth->data_offset, SEEK_SET, err) == -1) {
|
|
g_free(wth->capture.pcap);
|
|
return -1;
|
|
}
|
|
return 1;
|
|
|
|
case OTHER_FORMAT:
|
|
/*
|
|
* Try the next format.
|
|
*/
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Well, it's not completely unreadable,
|
|
* but it's not a standard file *nor* is it ss990417.
|
|
* Try it as a Nokia file; there are no other types
|
|
* to try after that, so we put the seek pointer back
|
|
* and treat it as a Nokia file.
|
|
*/
|
|
wth->file_type = WTAP_FILE_PCAP_NOKIA;
|
|
if (file_seek(wth->fh, wth->data_offset, SEEK_SET, err) == -1) {
|
|
g_free(wth->capture.pcap);
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
/* Try to read the first two records of the capture file. */
|
|
static libpcap_try_t libpcap_try(wtap *wth, int *err)
|
|
{
|
|
/*
|
|
* pcaprec_ss990915_hdr is the largest header type.
|
|
*/
|
|
struct pcaprec_ss990915_hdr first_rec_hdr, second_rec_hdr;
|
|
|
|
/*
|
|
* Attempt to read the first record's header.
|
|
*/
|
|
if (libpcap_read_header(wth, err, &first_rec_hdr, TRUE) == -1) {
|
|
if (*err == 0 || *err == WTAP_ERR_SHORT_READ) {
|
|
/*
|
|
* EOF or short read - assume the file is in this
|
|
* format.
|
|
* When our client tries to read the first packet
|
|
* they will presumably get the same EOF or short
|
|
* read.
|
|
*/
|
|
return THIS_FORMAT;
|
|
}
|
|
|
|
if (*err == WTAP_ERR_BAD_RECORD) {
|
|
/*
|
|
* The first record is bogus, so this is probably
|
|
* a corrupt file. Assume the file is in this
|
|
* format. When our client tries to read the
|
|
* first packet they will presumably get the
|
|
* same bogus record.
|
|
*/
|
|
return THIS_FORMAT;
|
|
}
|
|
|
|
/*
|
|
* Some other error, e.g. an I/O error; just give up.
|
|
*/
|
|
return BAD_READ;
|
|
}
|
|
|
|
/*
|
|
* Now skip over the first record's data, under the assumption
|
|
* that the header is sane.
|
|
*/
|
|
if (file_seek(wth->fh, first_rec_hdr.hdr.incl_len, SEEK_CUR, err) == -1)
|
|
return BAD_READ;
|
|
|
|
/*
|
|
* Now attempt to read the second record's header.
|
|
*/
|
|
if (libpcap_read_header(wth, err, &second_rec_hdr, TRUE) == -1) {
|
|
if (*err == 0 || *err == WTAP_ERR_SHORT_READ) {
|
|
/*
|
|
* EOF or short read - assume the file is in this
|
|
* format.
|
|
* When our client tries to read the second packet
|
|
* they will presumably get the same EOF or short
|
|
* read.
|
|
*/
|
|
return THIS_FORMAT;
|
|
}
|
|
|
|
if (*err == WTAP_ERR_BAD_RECORD) {
|
|
/*
|
|
* The second record is bogus; maybe it's a
|
|
* Capture File From Hell, and what looks like
|
|
* the "header" of the next packet is actually
|
|
* random junk from the middle of a packet.
|
|
* Try the next format; if we run out of formats,
|
|
* it probably *is* a corrupt file.
|
|
*/
|
|
return OTHER_FORMAT;
|
|
}
|
|
|
|
/*
|
|
* Some other error, e.g. an I/O error; just give up.
|
|
*/
|
|
return BAD_READ;
|
|
}
|
|
|
|
/*
|
|
* OK, the first two records look OK; assume this is the
|
|
* right format.
|
|
*/
|
|
return THIS_FORMAT;
|
|
}
|
|
|
|
/* Read the next packet */
|
|
static gboolean libpcap_read(wtap *wth, int *err, long *data_offset)
|
|
{
|
|
struct pcaprec_ss990915_hdr hdr;
|
|
guint packet_size;
|
|
guint orig_size;
|
|
int bytes_read;
|
|
char fddi_padding[3];
|
|
|
|
bytes_read = libpcap_read_header(wth, err, &hdr, FALSE);
|
|
if (bytes_read == -1) {
|
|
/*
|
|
* We failed to read the header.
|
|
*/
|
|
return FALSE;
|
|
}
|
|
|
|
wth->data_offset += bytes_read;
|
|
packet_size = hdr.hdr.incl_len;
|
|
orig_size = hdr.hdr.orig_len;
|
|
|
|
/*
|
|
* AIX appears to put 3 bytes of padding in front of FDDI
|
|
* frames; strip that crap off.
|
|
*/
|
|
if (wth->file_type == WTAP_FILE_PCAP_AIX &&
|
|
(wth->file_encap == WTAP_ENCAP_FDDI ||
|
|
wth->file_encap == WTAP_ENCAP_FDDI_BITSWAPPED)) {
|
|
/*
|
|
* The packet size is really a record size and includes
|
|
* the padding.
|
|
*/
|
|
packet_size -= 3;
|
|
orig_size -= 3;
|
|
wth->data_offset += 3;
|
|
|
|
/*
|
|
* Read the padding.
|
|
*/
|
|
if (!libpcap_read_rec_data(wth->fh, fddi_padding, 3, err))
|
|
return FALSE; /* Read error */
|
|
}
|
|
|
|
*data_offset = wth->data_offset;
|
|
|
|
/*
|
|
* If this is an ATM packet, the first four bytes are the
|
|
* direction of the packet (transmit/receive), the VPI, and
|
|
* the VCI; read them and generate the pseudo-header from
|
|
* them.
|
|
*/
|
|
switch (wth->file_encap) {
|
|
|
|
case WTAP_ENCAP_ATM_PDUS:
|
|
if (packet_size < sizeof (struct sunatm_hdr)) {
|
|
/*
|
|
* Uh-oh, the packet isn't big enough to even
|
|
* have a pseudo-header.
|
|
*/
|
|
g_message("libpcap: SunATM file has a %u-byte packet, too small to have even an ATM pseudo-header\n",
|
|
packet_size);
|
|
*err = WTAP_ERR_BAD_RECORD;
|
|
return FALSE;
|
|
}
|
|
if (!libpcap_read_atm_pseudoheader(wth->fh, &wth->pseudo_header,
|
|
err))
|
|
return FALSE; /* Read error */
|
|
|
|
/*
|
|
* Don't count the pseudo-header as part of the packet.
|
|
*/
|
|
orig_size -= sizeof (struct sunatm_hdr);
|
|
packet_size -= sizeof (struct sunatm_hdr);
|
|
wth->data_offset += sizeof (struct sunatm_hdr);
|
|
break;
|
|
|
|
case WTAP_ENCAP_ETHERNET:
|
|
/*
|
|
* We don't know whether there's an FCS in this frame or not.
|
|
*/
|
|
wth->pseudo_header.eth.fcs_len = -1;
|
|
break;
|
|
}
|
|
|
|
buffer_assure_space(wth->frame_buffer, packet_size);
|
|
if (!libpcap_read_rec_data(wth->fh, buffer_start_ptr(wth->frame_buffer),
|
|
packet_size, err))
|
|
return FALSE; /* Read error */
|
|
wth->data_offset += packet_size;
|
|
|
|
wth->phdr.ts.tv_sec = hdr.hdr.ts_sec;
|
|
wth->phdr.ts.tv_usec = hdr.hdr.ts_usec;
|
|
wth->phdr.caplen = packet_size;
|
|
wth->phdr.len = orig_size;
|
|
wth->phdr.pkt_encap = wth->file_encap;
|
|
|
|
/*
|
|
* If this is ATM LANE traffic, try to guess what type of LANE
|
|
* traffic it is based on the packet contents.
|
|
*/
|
|
if (wth->file_encap == WTAP_ENCAP_ATM_PDUS &&
|
|
wth->pseudo_header.atm.type == TRAF_LANE) {
|
|
atm_guess_lane_type(buffer_start_ptr(wth->frame_buffer),
|
|
wth->phdr.caplen, &wth->pseudo_header);
|
|
}
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
static gboolean
|
|
libpcap_seek_read(wtap *wth, long seek_off,
|
|
union wtap_pseudo_header *pseudo_header, guchar *pd, int length, int *err)
|
|
{
|
|
if (file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1)
|
|
return FALSE;
|
|
|
|
switch (wth->file_encap) {
|
|
|
|
case WTAP_ENCAP_ATM_PDUS:
|
|
if (!libpcap_read_atm_pseudoheader(wth->random_fh, pseudo_header,
|
|
err)) {
|
|
/* Read error */
|
|
return FALSE;
|
|
}
|
|
break;
|
|
|
|
case WTAP_ENCAP_ETHERNET:
|
|
/*
|
|
* We don't know whether there's an FCS in this frame or not.
|
|
*/
|
|
pseudo_header->eth.fcs_len = -1;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Read the packet data.
|
|
*/
|
|
if (!libpcap_read_rec_data(wth->random_fh, pd, length, err))
|
|
return FALSE; /* failed */
|
|
|
|
/*
|
|
* If this is ATM LANE traffic, try to guess what type of LANE
|
|
* traffic it is based on the packet contents.
|
|
*/
|
|
if (wth->file_encap == WTAP_ENCAP_ATM_PDUS &&
|
|
pseudo_header->atm.type == TRAF_LANE)
|
|
atm_guess_lane_type(pd, length, pseudo_header);
|
|
return TRUE;
|
|
}
|
|
|
|
/* Read the header of the next packet; if "silent" is TRUE, don't complain
|
|
to the console, as we're testing to see if the file appears to be of a
|
|
particular type.
|
|
|
|
Return -1 on an error, or the number of bytes of header read on success. */
|
|
static int libpcap_read_header(wtap *wth, int *err,
|
|
struct pcaprec_ss990915_hdr *hdr, gboolean silent)
|
|
{
|
|
int bytes_to_read, bytes_read;
|
|
|
|
/* Read record header. */
|
|
errno = WTAP_ERR_CANT_READ;
|
|
switch (wth->file_type) {
|
|
|
|
case WTAP_FILE_PCAP:
|
|
case WTAP_FILE_PCAP_AIX:
|
|
bytes_to_read = sizeof (struct pcaprec_hdr);
|
|
break;
|
|
|
|
case WTAP_FILE_PCAP_SS990417:
|
|
case WTAP_FILE_PCAP_SS991029:
|
|
bytes_to_read = sizeof (struct pcaprec_modified_hdr);
|
|
break;
|
|
|
|
case WTAP_FILE_PCAP_SS990915:
|
|
bytes_to_read = sizeof (struct pcaprec_ss990915_hdr);
|
|
break;
|
|
|
|
case WTAP_FILE_PCAP_NOKIA:
|
|
bytes_to_read = sizeof (struct pcaprec_nokia_hdr);
|
|
break;
|
|
|
|
default:
|
|
g_assert_not_reached();
|
|
bytes_to_read = 0;
|
|
}
|
|
bytes_read = file_read(hdr, 1, bytes_to_read, wth->fh);
|
|
if (bytes_read != bytes_to_read) {
|
|
*err = file_error(wth->fh);
|
|
if (*err == 0 && bytes_read != 0) {
|
|
*err = WTAP_ERR_SHORT_READ;
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
adjust_header(wth, &hdr->hdr);
|
|
|
|
if (hdr->hdr.incl_len > WTAP_MAX_PACKET_SIZE) {
|
|
/*
|
|
* Probably a corrupt capture file; return an error,
|
|
* so that our caller doesn't blow up trying to allocate
|
|
* space for an immensely-large packet, and so that
|
|
* the code to try to guess what type of libpcap file
|
|
* this is can tell when it's not the type we're guessing
|
|
* it is.
|
|
*/
|
|
if (!silent) {
|
|
g_message("pcap: File has %u-byte packet, bigger than maximum of %u",
|
|
hdr->hdr.incl_len, WTAP_MAX_PACKET_SIZE);
|
|
}
|
|
*err = WTAP_ERR_BAD_RECORD;
|
|
return -1;
|
|
}
|
|
|
|
if (hdr->hdr.orig_len > WTAP_MAX_PACKET_SIZE) {
|
|
/*
|
|
* Probably a corrupt capture file; return an error,
|
|
* so that our caller doesn't blow up trying to
|
|
* cope with a huge "real" packet length, and so that
|
|
* the code to try to guess what type of libpcap file
|
|
* this is can tell when it's not the type we're guessing
|
|
* it is.
|
|
*/
|
|
if (!silent) {
|
|
g_message("pcap: File has %u-byte packet, bigger than maximum of %u",
|
|
hdr->hdr.orig_len, WTAP_MAX_PACKET_SIZE);
|
|
}
|
|
*err = WTAP_ERR_BAD_RECORD;
|
|
return -1;
|
|
}
|
|
|
|
return bytes_read;
|
|
}
|
|
|
|
static void
|
|
adjust_header(wtap *wth, struct pcaprec_hdr *hdr)
|
|
{
|
|
guint32 temp;
|
|
|
|
if (wth->capture.pcap->byte_swapped) {
|
|
/* Byte-swap the record header fields. */
|
|
hdr->ts_sec = BSWAP32(hdr->ts_sec);
|
|
hdr->ts_usec = BSWAP32(hdr->ts_usec);
|
|
hdr->incl_len = BSWAP32(hdr->incl_len);
|
|
hdr->orig_len = BSWAP32(hdr->orig_len);
|
|
}
|
|
|
|
/* If this is AIX, convert the time stamp from seconds/nanoseconds
|
|
to seconds/microseconds. */
|
|
if (wth->file_type == WTAP_FILE_PCAP_AIX)
|
|
hdr->ts_usec = hdr->ts_usec/1000;
|
|
|
|
/* Swap the "incl_len" and "orig_len" fields, if necessary. */
|
|
switch (wth->capture.pcap->lengths_swapped) {
|
|
|
|
case NOT_SWAPPED:
|
|
break;
|
|
|
|
case MAYBE_SWAPPED:
|
|
if (hdr->incl_len <= hdr->orig_len) {
|
|
/*
|
|
* The captured length is <= the actual length,
|
|
* so presumably they weren't swapped.
|
|
*/
|
|
break;
|
|
}
|
|
/* FALLTHROUGH */
|
|
|
|
case SWAPPED:
|
|
temp = hdr->orig_len;
|
|
hdr->orig_len = hdr->incl_len;
|
|
hdr->incl_len = temp;
|
|
break;
|
|
}
|
|
}
|
|
|
|
static void
|
|
libpcap_get_atm_pseudoheader(const struct sunatm_hdr *atm_phdr,
|
|
union wtap_pseudo_header *pseudo_header)
|
|
{
|
|
guint8 vpi;
|
|
guint16 vci;
|
|
|
|
vpi = atm_phdr->vpi;
|
|
vci = pntohs(&atm_phdr->vci);
|
|
|
|
/*
|
|
* The lower 4 bits of the first byte of the header indicate
|
|
* the type of traffic, as per the "atmioctl.h" header in
|
|
* SunATM.
|
|
*/
|
|
switch (atm_phdr->flags & 0x0F) {
|
|
|
|
case 0x01: /* LANE */
|
|
pseudo_header->atm.aal = AAL_5;
|
|
pseudo_header->atm.type = TRAF_LANE;
|
|
break;
|
|
|
|
case 0x02: /* RFC 1483 LLC multiplexed traffic */
|
|
pseudo_header->atm.aal = AAL_5;
|
|
pseudo_header->atm.type = TRAF_LLCMX;
|
|
break;
|
|
|
|
case 0x05: /* ILMI */
|
|
pseudo_header->atm.aal = AAL_5;
|
|
pseudo_header->atm.type = TRAF_ILMI;
|
|
break;
|
|
|
|
case 0x06: /* Q.2931 */
|
|
pseudo_header->atm.aal = AAL_SIGNALLING;
|
|
pseudo_header->atm.type = TRAF_UNKNOWN;
|
|
break;
|
|
|
|
case 0x03: /* MARS (RFC 2022) */
|
|
pseudo_header->atm.aal = AAL_5;
|
|
pseudo_header->atm.type = TRAF_UNKNOWN;
|
|
break;
|
|
|
|
case 0x04: /* IFMP (Ipsilon Flow Management Protocol; see RFC 1954) */
|
|
pseudo_header->atm.aal = AAL_5;
|
|
pseudo_header->atm.type = TRAF_UNKNOWN; /* XXX - TRAF_IPSILON? */
|
|
break;
|
|
|
|
default:
|
|
/*
|
|
* Assume it's AAL5, unless it's VPI 0 and VCI 5, in which
|
|
* case assume it's AAL_SIGNALLING; we know nothing more
|
|
* about it.
|
|
*
|
|
* XXX - is this necessary? Or are we guaranteed that
|
|
* all signalling traffic has a type of 0x06?
|
|
*
|
|
* XXX - is this guaranteed to be AAL5? Or, if the type is
|
|
* 0x00 ("raw"), might it be non-AAL5 traffic?
|
|
*/
|
|
if (vpi == 0 && vci == 5)
|
|
pseudo_header->atm.aal = AAL_SIGNALLING;
|
|
else
|
|
pseudo_header->atm.aal = AAL_5;
|
|
pseudo_header->atm.type = TRAF_UNKNOWN;
|
|
break;
|
|
}
|
|
pseudo_header->atm.subtype = TRAF_ST_UNKNOWN;
|
|
|
|
pseudo_header->atm.vpi = vpi;
|
|
pseudo_header->atm.vci = vci;
|
|
pseudo_header->atm.channel = (atm_phdr->flags & 0x80) ? 0 : 1;
|
|
|
|
/* We don't have this information */
|
|
pseudo_header->atm.flags = 0;
|
|
pseudo_header->atm.cells = 0;
|
|
pseudo_header->atm.aal5t_u2u = 0;
|
|
pseudo_header->atm.aal5t_len = 0;
|
|
pseudo_header->atm.aal5t_chksum = 0;
|
|
}
|
|
|
|
static gboolean
|
|
libpcap_read_atm_pseudoheader(FILE_T fh, union wtap_pseudo_header *pseudo_header,
|
|
int *err)
|
|
{
|
|
struct sunatm_hdr atm_phdr;
|
|
int bytes_read;
|
|
|
|
errno = WTAP_ERR_CANT_READ;
|
|
bytes_read = file_read(&atm_phdr, 1, sizeof (struct sunatm_hdr), fh);
|
|
if (bytes_read != sizeof (struct sunatm_hdr)) {
|
|
*err = file_error(fh);
|
|
if (*err == 0)
|
|
*err = WTAP_ERR_SHORT_READ;
|
|
return FALSE;
|
|
}
|
|
|
|
libpcap_get_atm_pseudoheader(&atm_phdr, pseudo_header);
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
static gboolean
|
|
libpcap_read_rec_data(FILE_T fh, guchar *pd, int length, int *err)
|
|
{
|
|
int bytes_read;
|
|
|
|
errno = WTAP_ERR_CANT_READ;
|
|
bytes_read = file_read(pd, 1, length, fh);
|
|
|
|
if (bytes_read != length) {
|
|
*err = file_error(fh);
|
|
if (*err == 0)
|
|
*err = WTAP_ERR_SHORT_READ;
|
|
return FALSE;
|
|
}
|
|
return TRUE;
|
|
}
|
|
|
|
static void
|
|
libpcap_close(wtap *wth)
|
|
{
|
|
g_free(wth->capture.pcap);
|
|
}
|
|
|
|
static int wtap_wtap_encap_to_pcap_encap(int encap)
|
|
{
|
|
unsigned int i;
|
|
|
|
switch (encap) {
|
|
|
|
case WTAP_ENCAP_FDDI:
|
|
case WTAP_ENCAP_FDDI_BITSWAPPED:
|
|
/*
|
|
* Special-case WTAP_ENCAP_FDDI and
|
|
* WTAP_ENCAP_FDDI_BITSWAPPED; both of them get mapped
|
|
* to DLT_FDDI (even though that may mean that the bit
|
|
* order in the FDDI MAC addresses is wrong; so it goes
|
|
* - libpcap format doesn't record the byte order,
|
|
* so that's not fixable).
|
|
*/
|
|
return 10; /* that's DLT_FDDI */
|
|
|
|
case WTAP_ENCAP_PPP_WITH_PHDR:
|
|
/*
|
|
* Also special-case PPP and Frame Relay with direction
|
|
* bits; map them to PPP and Frame Relay, even though
|
|
* that means that the direction of the packet is lost.
|
|
*/
|
|
return 9;
|
|
|
|
case WTAP_ENCAP_FRELAY_WITH_PHDR:
|
|
return 107;
|
|
}
|
|
|
|
for (i = 0; i < NUM_PCAP_ENCAPS; i++) {
|
|
if (pcap_to_wtap_map[i].wtap_encap_value == encap)
|
|
return pcap_to_wtap_map[i].dlt_value;
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
#ifdef HAVE_PCAP_H
|
|
/*
|
|
* Given a Wiretap encapsulation type, and raw packet data and the packet
|
|
* header from libpcap, process any pseudo-header in the packet,
|
|
* fill in the Wiretap packet header, and return a pointer to the
|
|
* beginning of the non-pseudo-header data in the packet.
|
|
*/
|
|
const guchar *
|
|
wtap_process_pcap_packet(gint linktype, const struct pcap_pkthdr *phdr,
|
|
const guchar *pd, union wtap_pseudo_header *pseudo_header,
|
|
struct wtap_pkthdr *whdr, int *err)
|
|
{
|
|
/* "phdr->ts" may not necessarily be a "struct timeval" - it may
|
|
be a "struct bpf_timeval", with member sizes wired to 32
|
|
bits - and we may go that way ourselves in the future, so
|
|
copy the members individually. */
|
|
whdr->ts.tv_sec = phdr->ts.tv_sec;
|
|
whdr->ts.tv_usec = phdr->ts.tv_usec;
|
|
whdr->caplen = phdr->caplen;
|
|
whdr->len = phdr->len;
|
|
whdr->pkt_encap = linktype;
|
|
|
|
/*
|
|
* If this is an ATM packet, the first four bytes are the
|
|
* direction of the packet (transmit/receive), the VPI, and
|
|
* the VCI; read them and generate the pseudo-header from
|
|
* them.
|
|
*/
|
|
if (linktype == WTAP_ENCAP_ATM_PDUS) {
|
|
if (whdr->caplen < sizeof (struct sunatm_hdr)) {
|
|
/*
|
|
* Uh-oh, the packet isn't big enough to even
|
|
* have a pseudo-header.
|
|
*/
|
|
g_message("libpcap: SunATM capture has a %u-byte packet, too small to have even an ATM pseudo-header\n",
|
|
whdr->caplen);
|
|
*err = WTAP_ERR_BAD_RECORD;
|
|
return NULL;
|
|
}
|
|
libpcap_get_atm_pseudoheader((const struct sunatm_hdr *)pd,
|
|
pseudo_header);
|
|
|
|
/*
|
|
* Don't count the pseudo-header as part of the packet.
|
|
*/
|
|
whdr->len -= sizeof (struct sunatm_hdr);
|
|
whdr->caplen -= sizeof (struct sunatm_hdr);
|
|
pd += sizeof (struct sunatm_hdr);
|
|
|
|
/*
|
|
* If this is ATM LANE traffic, try to guess what type of
|
|
* LANE traffic it is based on the packet contents.
|
|
*/
|
|
if (pseudo_header->atm.type == TRAF_LANE)
|
|
atm_guess_lane_type(pd, whdr->caplen, pseudo_header);
|
|
}
|
|
return pd;
|
|
}
|
|
#endif
|
|
|
|
/* Returns 0 if we could write the specified encapsulation type,
|
|
an error indication otherwise. */
|
|
int libpcap_dump_can_write_encap(int encap)
|
|
{
|
|
/* Per-packet encapsulations aren't supported. */
|
|
if (encap == WTAP_ENCAP_PER_PACKET)
|
|
return WTAP_ERR_ENCAP_PER_PACKET_UNSUPPORTED;
|
|
|
|
if (wtap_wtap_encap_to_pcap_encap(encap) == -1)
|
|
return WTAP_ERR_UNSUPPORTED_ENCAP;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Returns TRUE on success, FALSE on failure; sets "*err" to an error code on
|
|
failure */
|
|
gboolean libpcap_dump_open(wtap_dumper *wdh, gboolean cant_seek _U_, int *err)
|
|
{
|
|
guint32 magic;
|
|
struct pcap_hdr file_hdr;
|
|
size_t nwritten;
|
|
|
|
/* This is a libpcap file */
|
|
wdh->subtype_write = libpcap_dump;
|
|
wdh->subtype_close = NULL;
|
|
|
|
/* Write the file header. */
|
|
switch (wdh->file_type) {
|
|
|
|
case WTAP_FILE_PCAP:
|
|
case WTAP_FILE_PCAP_SS990417: /* modified, but with the old magic, sigh */
|
|
case WTAP_FILE_PCAP_NOKIA: /* Nokia libpcap of some sort */
|
|
magic = PCAP_MAGIC;
|
|
break;
|
|
|
|
case WTAP_FILE_PCAP_SS990915: /* new magic, extra crap */
|
|
case WTAP_FILE_PCAP_SS991029:
|
|
magic = PCAP_MODIFIED_MAGIC;
|
|
break;
|
|
|
|
default:
|
|
/* We should never get here - our open routine
|
|
should only get called for the types above. */
|
|
*err = WTAP_ERR_UNSUPPORTED_FILE_TYPE;
|
|
return FALSE;
|
|
}
|
|
|
|
nwritten = fwrite(&magic, 1, sizeof magic, wdh->fh);
|
|
if (nwritten != sizeof magic) {
|
|
if (nwritten == 0 && ferror(wdh->fh))
|
|
*err = errno;
|
|
else
|
|
*err = WTAP_ERR_SHORT_WRITE;
|
|
return FALSE;
|
|
}
|
|
wdh->bytes_dumped += sizeof magic;
|
|
|
|
/* current "libpcap" format is 2.4 */
|
|
file_hdr.version_major = 2;
|
|
file_hdr.version_minor = 4;
|
|
file_hdr.thiszone = 0; /* XXX - current offset? */
|
|
file_hdr.sigfigs = 0; /* unknown, but also apparently unused */
|
|
/*
|
|
* Tcpdump cannot handle capture files with a snapshot length of 0,
|
|
* as BPF filters return either 0 if they fail or the snapshot length
|
|
* if they succeed, and a snapshot length of 0 means success is
|
|
* indistinguishable from failure and the filter expression would
|
|
* reject all packets.
|
|
*
|
|
* A snapshot length of 0, inside Wiretap, means "snapshot length
|
|
* unknown"; if the snapshot length supplied to us is 0, we make
|
|
* the snapshot length in the header file WTAP_MAX_PACKET_SIZE.
|
|
*/
|
|
file_hdr.snaplen = (wdh->snaplen != 0) ? wdh->snaplen :
|
|
WTAP_MAX_PACKET_SIZE;
|
|
file_hdr.network = wtap_wtap_encap_to_pcap_encap(wdh->encap);
|
|
nwritten = fwrite(&file_hdr, 1, sizeof file_hdr, wdh->fh);
|
|
if (nwritten != sizeof file_hdr) {
|
|
if (nwritten == 0 && ferror(wdh->fh))
|
|
*err = errno;
|
|
else
|
|
*err = WTAP_ERR_SHORT_WRITE;
|
|
return FALSE;
|
|
}
|
|
wdh->bytes_dumped += sizeof file_hdr;
|
|
|
|
return TRUE;
|
|
}
|
|
|
|
/* Write a record for a packet to a dump file.
|
|
Returns TRUE on success, FALSE on failure. */
|
|
static gboolean libpcap_dump(wtap_dumper *wdh,
|
|
const struct wtap_pkthdr *phdr,
|
|
const union wtap_pseudo_header *pseudo_header _U_,
|
|
const guchar *pd, int *err)
|
|
{
|
|
struct pcaprec_ss990915_hdr rec_hdr;
|
|
size_t hdr_size;
|
|
size_t nwritten;
|
|
struct sunatm_hdr atm_hdr;
|
|
int atm_hdrsize;
|
|
|
|
if (wdh->encap == WTAP_ENCAP_ATM_PDUS)
|
|
atm_hdrsize = sizeof (struct sunatm_hdr);
|
|
else
|
|
atm_hdrsize = 0;
|
|
|
|
rec_hdr.hdr.ts_sec = phdr->ts.tv_sec;
|
|
rec_hdr.hdr.ts_usec = phdr->ts.tv_usec;
|
|
rec_hdr.hdr.incl_len = phdr->caplen + atm_hdrsize;
|
|
rec_hdr.hdr.orig_len = phdr->len + atm_hdrsize;
|
|
switch (wdh->file_type) {
|
|
|
|
case WTAP_FILE_PCAP:
|
|
hdr_size = sizeof (struct pcaprec_hdr);
|
|
break;
|
|
|
|
case WTAP_FILE_PCAP_SS990417: /* modified, but with the old magic, sigh */
|
|
case WTAP_FILE_PCAP_SS991029:
|
|
/* XXX - what should we supply here?
|
|
|
|
Alexey's "libpcap" looks up the interface in the system's
|
|
interface list if "ifindex" is non-zero, and prints
|
|
the interface name. It ignores "protocol", and uses
|
|
"pkt_type" to tag the packet as "host", "broadcast",
|
|
"multicast", "other host", "outgoing", or "none of the
|
|
above", but that's it.
|
|
|
|
If the capture we're writing isn't a modified or
|
|
RH 6.1 capture, we'd have to do some work to
|
|
generate the packet type and interface index - and
|
|
we can't generate the interface index unless we
|
|
just did the capture ourselves in any case.
|
|
|
|
I'm inclined to continue to punt; systems other than
|
|
those with the older patch can read standard "libpcap"
|
|
files, and systems with the older patch, e.g. RH 6.1,
|
|
will just have to live with this. */
|
|
rec_hdr.ifindex = 0;
|
|
rec_hdr.protocol = 0;
|
|
rec_hdr.pkt_type = 0;
|
|
hdr_size = sizeof (struct pcaprec_modified_hdr);
|
|
break;
|
|
|
|
case WTAP_FILE_PCAP_SS990915: /* new magic, extra crap at the end */
|
|
rec_hdr.ifindex = 0;
|
|
rec_hdr.protocol = 0;
|
|
rec_hdr.pkt_type = 0;
|
|
rec_hdr.cpu1 = 0;
|
|
rec_hdr.cpu2 = 0;
|
|
hdr_size = sizeof (struct pcaprec_ss990915_hdr);
|
|
break;
|
|
|
|
case WTAP_FILE_PCAP_NOKIA: /* old magic, extra crap at the end */
|
|
rec_hdr.ifindex = 0;
|
|
rec_hdr.protocol = 0;
|
|
rec_hdr.pkt_type = 0;
|
|
rec_hdr.cpu1 = 0;
|
|
rec_hdr.cpu2 = 0;
|
|
hdr_size = sizeof (struct pcaprec_nokia_hdr);
|
|
break;
|
|
|
|
default:
|
|
/* We should never get here - our open routine
|
|
should only get called for the types above. */
|
|
g_assert_not_reached();
|
|
*err = WTAP_ERR_UNSUPPORTED_FILE_TYPE;
|
|
return FALSE;
|
|
}
|
|
|
|
nwritten = fwrite(&rec_hdr, 1, hdr_size, wdh->fh);
|
|
if (nwritten != hdr_size) {
|
|
if (nwritten == 0 && ferror(wdh->fh))
|
|
*err = errno;
|
|
else
|
|
*err = WTAP_ERR_SHORT_WRITE;
|
|
return FALSE;
|
|
}
|
|
wdh->bytes_dumped += hdr_size;
|
|
|
|
if (wdh->encap == WTAP_ENCAP_ATM_PDUS) {
|
|
/*
|
|
* Write the ATM header.
|
|
*/
|
|
atm_hdr.flags =
|
|
(pseudo_header->atm.channel == 0) ? 0x80 : 0x00;
|
|
switch (pseudo_header->atm.aal) {
|
|
|
|
case AAL_SIGNALLING:
|
|
/* Q.2931 */
|
|
atm_hdr.flags |= 0x06;
|
|
break;
|
|
|
|
case AAL_5:
|
|
switch (pseudo_header->atm.type) {
|
|
|
|
case TRAF_LANE:
|
|
/* LANE */
|
|
atm_hdr.flags |= 0x01;
|
|
break;
|
|
|
|
case TRAF_LLCMX:
|
|
/* RFC 1483 LLC multiplexed traffic */
|
|
atm_hdr.flags |= 0x02;
|
|
break;
|
|
|
|
case TRAF_ILMI:
|
|
/* ILMI */
|
|
atm_hdr.flags |= 0x05;
|
|
break;
|
|
}
|
|
break;
|
|
}
|
|
atm_hdr.vpi = pseudo_header->atm.vpi;
|
|
atm_hdr.vci = phtons(&pseudo_header->atm.vci);
|
|
nwritten = fwrite(&atm_hdr, 1, sizeof atm_hdr, wdh->fh);
|
|
if (nwritten != sizeof atm_hdr) {
|
|
if (nwritten == 0 && ferror(wdh->fh))
|
|
*err = errno;
|
|
else
|
|
*err = WTAP_ERR_SHORT_WRITE;
|
|
return FALSE;
|
|
}
|
|
wdh->bytes_dumped += sizeof atm_hdr;
|
|
}
|
|
|
|
nwritten = fwrite(pd, 1, phdr->caplen, wdh->fh);
|
|
if (nwritten != phdr->caplen) {
|
|
if (nwritten == 0 && ferror(wdh->fh))
|
|
*err = errno;
|
|
else
|
|
*err = WTAP_ERR_SHORT_WRITE;
|
|
return FALSE;
|
|
}
|
|
wdh->bytes_dumped += phdr->caplen;
|
|
return TRUE;
|
|
}
|