/* libpcap.c
*
- * $Id: libpcap.c,v 1.5 1999/07/13 02:53:24 gram Exp $
+ * $Id: libpcap.c,v 1.101 2003/12/03 22:40:39 guy Exp $
*
* Wiretap Library
- * Copyright (c) 1998 by Gilbert Ramirez <gram@verdict.uthscsa.edu>
- *
+ * Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
+ *
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
- *
+ *
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
- *
+ *
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- *
*/
+
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
-#include "wtap.h"
+
+#include <stdlib.h>
+#include <errno.h>
+#include "wtap-int.h"
+#include "file_wrappers.h"
#include "buffer.h"
+#include "atm.h"
#include "libpcap.h"
+#ifdef HAVE_PCAP_H
+# ifdef HAVE_SYS_TYPES_H
+# include <sys/types.h>
+# endif
+#include <pcap.h>
+#include "wtap-capture.h"
+#endif
+
+/*
+ * The link-layer header on ATM packets.
+ */
+struct sunatm_hdr {
+ guint8 flags; /* destination and traffic type */
+ guint8 vpi; /* VPI */
+ guint16 vci; /* VCI */
+};
+
/* See source to the "libpcap" library for information on the "libpcap"
file format. */
-/* Magic numbers in "libpcap" files.
-
- "libpcap" file records are written in the byte order of the host that
- writes them, and the reader is expected to fix this up.
-
- PCAP_MAGIC is the magic number, in host byte order; PCAP_SWAPPED_MAGIC
- is a byte-swapped version of that. */
-#define PCAP_MAGIC 0xa1b2c3d4
-#define PCAP_SWAPPED_MAGIC 0xd4c3b2a1
-
-/* Macros to byte-swap 32-bit and 16-bit quantities. */
-#define BSWAP32(x) \
- ((((x)&0xFF000000)>>24) | \
- (((x)&0x00FF0000)>>8) | \
- (((x)&0x0000FF00)<<8) | \
- (((x)&0x000000FF)<<24))
-#define BSWAP16(x) \
- ((((x)&0xFF00)>>8) | \
- (((x)&0x00FF)<<8))
-
-/* "libpcap" file header (minus magic number). */
-struct pcap_hdr {
- guint16 version_major; /* major version number */
- guint16 version_minor; /* minor version number */
- gint32 thiszone; /* GMT to local correction */
- guint32 sigfigs; /* accuracy of timestamps */
- guint32 snaplen; /* max length of captured packets, in octets */
- guint32 network; /* data link type */
-};
+/* On some systems, the FDDI MAC addresses are bit-swapped. */
+#if !defined(ultrix) && !defined(__alpha) && !defined(__bsdi__)
+#define BIT_SWAPPED_MAC_ADDRS
+#endif
+
+/* Try to read the first two records of the capture file. */
+typedef enum {
+ THIS_FORMAT, /* the reads succeeded, assume it's this format */
+ BAD_READ, /* the file is probably not valid */
+ OTHER_FORMAT /* the file may be valid, but not in this format */
+} libpcap_try_t;
+static libpcap_try_t libpcap_try(wtap *wth, int *err);
+
+static gboolean libpcap_read(wtap *wth, int *err, long *data_offset);
+static gboolean libpcap_seek_read(wtap *wth, long seek_off,
+ union wtap_pseudo_header *pseudo_header, guchar *pd, int length, int *err);
+static int libpcap_read_header(wtap *wth, int *err,
+ struct pcaprec_ss990915_hdr *hdr, gboolean silent);
+static void adjust_header(wtap *wth, struct pcaprec_hdr *hdr);
+static void libpcap_get_atm_pseudoheader(const struct sunatm_hdr *atm_phdr,
+ union wtap_pseudo_header *pseudo_header);
+static gboolean libpcap_read_atm_pseudoheader(FILE_T fh,
+ union wtap_pseudo_header *pseudo_header, int *err);
+static gboolean libpcap_read_rec_data(FILE_T fh, guchar *pd, int length,
+ int *err);
+static void libpcap_close(wtap *wth);
+static gboolean libpcap_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
+ const union wtap_pseudo_header *pseudo_header, const guchar *pd, int *err);
+
+/*
+ * Either LBL NRG wasn't an adequate central registry (e.g., because of
+ * the slow rate of releases from them), or nobody bothered using them
+ * as a central registry, as many different groups have patched libpcap
+ * (and BPF, on the BSDs) to add new encapsulation types, and have ended
+ * up using the same DLT_ values for different encapsulation types.
+ *
+ * For those numerical encapsulation type values that everybody uses for
+ * the same encapsulation type (which inclues those that some platforms
+ * specify different DLT_ names for but don't appear to use), we map
+ * those values to the appropriate Wiretap values.
+ *
+ * For those numerical encapsulation type values that different libpcap
+ * variants use for different encapsulation types, we check what
+ * <pcap.h> defined to determine how to interpret them, so that we
+ * interpret them the way the libpcap with which we're building
+ * Ethereal/Wiretap interprets them (which, if it doesn't support
+ * them at all, means we don't support them either - any capture files
+ * using them are foreign, and we don't hazard a guess as to which
+ * platform they came from; we could, I guess, choose the most likely
+ * platform).
+ *
+ * Note: 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[]".
+ */
+
+static const struct {
+ int dlt_value;
+ int wtap_encap_value;
+} pcap_to_wtap_map[] = {
+ /*
+ * These are the values that are almost certainly the same
+ * in all libpcaps (I've yet to find one where the values
+ * in question are used for some purpose other than the
+ * one below, but...), and that Wiretap and Ethereal
+ * currently support.
+ */
+ { 0, WTAP_ENCAP_NULL }, /* null encapsulation */
+ { 1, WTAP_ENCAP_ETHERNET },
+ { 6, WTAP_ENCAP_TOKEN_RING }, /* IEEE 802 Networks - assume token ring */
+ { 7, WTAP_ENCAP_ARCNET },
+ { 8, WTAP_ENCAP_SLIP },
+ { 9, WTAP_ENCAP_PPP },
+#ifdef BIT_SWAPPED_MAC_ADDRS
+ { 10, WTAP_ENCAP_FDDI_BITSWAPPED },
+#else
+ { 10, WTAP_ENCAP_FDDI },
+#endif
+
+ /*
+ * 50 is DLT_PPP_SERIAL in NetBSD; it appears that DLT_PPP
+ * on BSD (at least according to standard tcpdump) has, as
+ * the first octet, an indication of whether the packet was
+ * transmitted or received (rather than having the standard
+ * PPP address value of 0xff), but that DLT_PPP_SERIAL puts
+ * a real live PPP header there, or perhaps a Cisco PPP header
+ * as per section 4.3.1 of RFC 1547 (implementations of this
+ * exist in various BSDs in "sys/net/if_spppsubr.c", and
+ * I think also exist either in standard Linux or in
+ * various Linux patches; the implementations show how to handle
+ * Cisco keepalive packets).
+ *
+ * However, I don't see any obvious place in FreeBSD "if_ppp.c"
+ * where anything other than the standard PPP header would be
+ * passed up. I see some stuff that sets the first octet
+ * to 0 for incoming and 1 for outgoing packets before applying
+ * a BPF filter to see whether to drop packets whose protocol
+ * field has the 0x8000 bit set, i.e. network control protocols -
+ * those are handed up to userland - but that code puts the
+ * address field back before passing the packet up.
+ *
+ * I also don't see anything immediately obvious that munges
+ * the address field for sync PPP, either.
+ *
+ * Ethereal currently assumes that if the first octet of a
+ * PPP frame is 0xFF, it's the address field and is followed
+ * by a control field and a 2-byte protocol, otherwise the
+ * address and control fields are absent and the frame begins
+ * with a protocol field. If we ever see a BSD/OS PPP
+ * capture, we'll have to handle it differently, and we may
+ * have to handle standard BSD captures differently if, in fact,
+ * they don't have 0xff 0x03 as the first two bytes - but, as per
+ * the two paragraphs preceding this, it's not clear that
+ * the address field *is* munged into an incoming/outgoing
+ * field when the packet is handed to the BPF device.
+ *
+ * For now, we just map DLT_PPP_SERIAL to WTAP_ENCAP_PPP, as
+ * we treat WTAP_ENCAP_PPP packets as if those beginning with
+ * 0xff have the standard RFC 1662 "PPP in HDLC-like Framing"
+ * 0xff 0x03 address/control header, and DLT_PPP_SERIAL frames
+ * appear to contain that unless they're Cisco frames (if we
+ * ever see a capture with them, we'd need to implement the
+ * RFC 1547 stuff, and the keepalive protocol stuff).
+ *
+ * We may have to distinguish between "PPP where if it doesn't
+ * begin with 0xff there's no HDLC encapsulation and the frame
+ * begins with the protocol field" (which is how we handle
+ * WTAP_ENCAP_PPP now) and "PPP where there's either HDLC
+ * encapsulation or Cisco PPP" (which is what DLT_PPP_SERIAL
+ * is) at some point.
+ *
+ * XXX - NetBSD has DLT_HDLC, which appears to be used for
+ * Cisco HDLC. Ideally, they should use DLT_PPP_SERIAL
+ * only for real live HDLC-encapsulated PPP, not for Cisco
+ * HDLC.
+ */
+ { 50, WTAP_ENCAP_PPP },
+
+ /*
+ * These are the values that libpcap 0.5 and later use in
+ * capture file headers, in an attempt to work around the
+ * confusion decried above, and that Wiretap and Ethereal
+ * currently support.
+ */
+ { 100, WTAP_ENCAP_ATM_RFC1483 },
+ { 101, WTAP_ENCAP_RAW_IP },
+#if 0
+ /*
+ * More values used by libpcap 0.5 as DLT_ values and used by the
+ * current CVS version of libpcap in capture file headers.
+ * They are not yet handled in Ethereal.
+ * If we get a capture that contains them, we'll implement them.
+ */
+ { 102, WTAP_ENCAP_SLIP_BSDOS },
+ { 103, WTAP_ENCAP_PPP_BSDOS },
+#endif
+
+ /*
+ * These ones are handled in Ethereal, though.
+ */
+ { 104, WTAP_ENCAP_CHDLC }, /* Cisco HDLC */
+ { 105, WTAP_ENCAP_IEEE_802_11 }, /* IEEE 802.11 */
+ { 106, WTAP_ENCAP_LINUX_ATM_CLIP },
+ { 107, WTAP_ENCAP_FRELAY }, /* Frame Relay */
+ { 108, WTAP_ENCAP_NULL }, /* OpenBSD loopback */
+ { 109, WTAP_ENCAP_ENC }, /* OpenBSD IPSEC enc */
+#if 0
+ { 110, WTAP_ENCAP_LANE_802_3 },/* ATM LANE 802.3 */
+ { 111, WTAP_ENCAP_HIPPI }, /* NetBSD HIPPI */
+#endif
+ { 112, WTAP_ENCAP_CHDLC }, /* NetBSD HDLC framing */
+
+ /*
+ * Linux "cooked mode" captures, used by the current CVS version
+ * of libpcap.
+ */
+ { 113, WTAP_ENCAP_SLL }, /* Linux cooked capture */
+
+ { 114, WTAP_ENCAP_LOCALTALK }, /* Localtalk */
+
+ /*
+ * The tcpdump.org version of libpcap uses 117, rather than 17,
+ * for OpenBSD packet filter logging, so as to avoid conflicting
+ * with DLT_LANE8023 in SuSE 6.3 libpcap.
+ */
+ { 117, WTAP_ENCAP_PFLOG },
+
+ { 118, WTAP_ENCAP_CISCO_IOS },
+ { 119, WTAP_ENCAP_PRISM_HEADER }, /* Prism monitor mode hdr */
+ { 121, WTAP_ENCAP_HHDLC }, /* HiPath HDLC */
+ { 122, WTAP_ENCAP_IP_OVER_FC }, /* RFC 2625 IP-over-FC */
+ { 123, WTAP_ENCAP_ATM_PDUS }, /* SunATM */
+ { 127, WTAP_ENCAP_WLAN_HEADER }, /* 802.11 plus WLAN header */
+ { 128, WTAP_ENCAP_TZSP }, /* Tazmen Sniffer Protocol */
+ { 129, WTAP_ENCAP_ARCNET_LINUX },
+
+ /*
+ * Values 130 thorugh 137 are reserved for use in Juniper
+ * hardware.
+ *
+ * 138 is reserved for Apple IP-over-IEEE 1394.
+ */
+
+ { 140, WTAP_ENCAP_MTP2 },
+ { 141, WTAP_ENCAP_MTP3 },
+
+ /*
+ * 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[]".
+ */
+
+ /*
+ * The following are entries for libpcap type values that have
+ * different meanings on different OSes.
+ *
+ * We put these *after* the entries for the platform-independent
+ * libpcap type values for those Wiretap encapsulation types, so
+ * that Ethereal chooses the platform-independent libpcap type
+ * value for those encapsulatioin types, not the platform-dependent
+ * one.
+ */
+
+ /*
+ * 11 is DLT_ATM_RFC1483 on most platforms; the only libpcaps I've
+ * seen that define anything other than DLT_ATM_RFC1483 as 11 are
+ * the BSD/OS one, which defines DLT_FR as 11, and libpcap 0.5,
+ * which define it as 100, mapping the kernel's value to 100, in
+ * an attempt to hide the different values used on different
+ * platforms.
+ *
+ * If this is a platform where DLT_FR is defined as 11, we
+ * don't handle 11 at all; otherwise, we handle it as
+ * DLT_ATM_RFC1483 (this means we'd misinterpret Frame Relay
+ * captures from BSD/OS if running on platforms other than BSD/OS,
+ * but
+ *
+ * 1) we don't yet support DLT_FR
+ *
+ * and
+ *
+ * 2) nothing short of a heuristic would let us interpret
+ * them correctly).
+ */
+#if defined(DLT_FR) && (DLT_FR == 11)
+ { 11, WTAP_ENCAP_FRELAY },
+#else
+ { 11, WTAP_ENCAP_ATM_RFC1483 },
+#endif
+
+ /*
+ * 12 is DLT_RAW on most platforms, but it's DLT_C_HDLC on
+ * BSD/OS, and DLT_LOOP on OpenBSD.
+ *
+ * We don't yet handle DLT_C_HDLC, but we can handle DLT_LOOP
+ * (it's just like DLT_NULL, only with the AF_ value in network
+ * rather than host byte order - Ethereal figures out the
+ * byte order from the data, so we don't care what byte order
+ * it's in), so if DLT_LOOP is defined as 12, interpret 12
+ * as WTAP_ENCAP_NULL, otherwise, unless DLT_C_HDLC is defined
+ * as 12, interpret it as WTAP_ENCAP_RAW_IP.
+ */
+#if defined(DLT_LOOP) && (DLT_LOOP == 12)
+ { 12, WTAP_ENCAP_NULL },
+#elif defined(DLT_C_HDLC) && (DLT_C_HDLC == 12)
+ /*
+ * Put entry for Cisco HDLC here.
+ * XXX - is this just WTAP_ENCAP_CHDLC, i.e. does the frame
+ * start with a 4-byte Cisco HDLC header?
+ */
+#else
+ { 12, WTAP_ENCAP_RAW_IP },
+#endif
+
+ /*
+ * 13 is DLT_SLIP_BSDOS on FreeBSD and NetBSD, but those OSes
+ * don't actually generate it. I infer that BSD/OS translates
+ * DLT_SLIP from the kernel BPF code to DLT_SLIP_BSDOS in
+ * libpcap, as the BSD/OS link-layer header is different;
+ * however, in BSD/OS, DLT_SLIP_BSDOS is 15.
+ *
+ * From this, I infer that there's no point in handling 13
+ * as DLT_SLIP_BSDOS.
+ *
+ * 13 is DLT_ATM_RFC1483 on BSD/OS.
+ *
+ * 13 is DLT_ENC in OpenBSD, which is, I suspect, some kind
+ * of decrypted IPSEC traffic.
+ */
+#if defined(DLT_ATM_RFC1483) && (DLT_ATM_RFC1483 == 13)
+ { 13, WTAP_ENCAP_ATM_RFC1483 },
+#elif defined(DLT_ENC) && (DLT_ENC == 13)
+ { 13, WTAP_ENCAP_ENC },
+#endif
+
+ /*
+ * 14 is DLT_PPP_BSDOS on FreeBSD and NetBSD, but those OSes
+ * don't actually generate it. I infer that BSD/OS translates
+ * DLT_PPP from the kernel BPF code to DLT_PPP_BSDOS in
+ * libpcap, as the BSD/OS link-layer header is different;
+ * however, in BSD/OS, DLT_PPP_BSDOS is 16.
+ *
+ * From this, I infer that there's no point in handling 14
+ * as DLT_PPP_BSDOS.
+ *
+ * 14 is DLT_RAW on BSD/OS and OpenBSD.
+ */
+ { 14, WTAP_ENCAP_RAW_IP },
+
+ /*
+ * 15 is:
+ *
+ * DLT_SLIP_BSDOS on BSD/OS;
+ *
+ * DLT_HIPPI on NetBSD;
+ *
+ * DLT_LANE8023 with Alexey Kuznetzov's patches for
+ * Linux libpcap;
+ *
+ * DLT_I4L_RAWIP with the ISDN4Linux patches for libpcap
+ * (and on SuSE 6.3);
+ *
+ * but we don't currently handle any of those.
+ */
+
+ /*
+ * 16 is:
+ *
+ * DLT_PPP_BSDOS on BSD/OS;
+ *
+ * DLT_HDLC on NetBSD (Cisco HDLC);
+ *
+ * DLT_CIP with Alexey Kuznetzov's patches for
+ * Linux libpcap - this is WTAP_ENCAP_LINUX_ATM_CLIP;
+ *
+ * DLT_I4L_IP with the ISDN4Linux patches for libpcap
+ * (and on SuSE 6.3).
+ */
+#if defined(DLT_CIP) && (DLT_CIP == 16)
+ { 16, WTAP_ENCAP_LINUX_ATM_CLIP },
+#endif
+#if defined(DLT_HDLC) && (DLT_HDLC == 16)
+ { 16, WTAP_ENCAP_CHDLC },
+#endif
+
+ /*
+ * 17 is DLT_LANE8023 in SuSE 6.3 libpcap; we don't currently
+ * handle it.
+ * It is also used as the PF (Packet Filter) logging format beginning
+ * with OpenBSD 3.0; we use 17 for PF logs unless DLT_LANE8023 is
+ * defined with the value 17.
+ */
+#if !defined(DLT_LANE8023) || (DLT_LANE8023 != 17)
+ { 17, WTAP_ENCAP_OLD_PFLOG },
+#endif
+
+ /*
+ * 18 is DLT_CIP in SuSE 6.3 libpcap; if it's the same as the
+ * DLT_CIP of 16 that the Alexey Kuznetzov patches for
+ * libpcap/tcpdump define, it's WTAP_ENCAP_LINUX_ATM_CLIP.
+ * I've not found any libpcap that uses it for any other purpose -
+ * hopefully nobody will do so in the future.
+ */
+ { 18, WTAP_ENCAP_LINUX_ATM_CLIP },
+
+ /*
+ * 19 is DLT_ATM_CLIP in the libpcap/tcpdump patches in the
+ * 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[]".
+ */
-/* "libpcap" record header. */
-struct pcaprec_hdr {
- guint32 ts_sec; /* timestamp seconds */
- guint32 ts_usec; /* timestamp microseconds */
- guint32 incl_len; /* number of octets captured in file */
- guint32 orig_len; /* actual length of packet */
};
+#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;
+}
-/* Returns WTAP_FILE_PCAP on success, WTAP_FILE_UNKNOWN on failure */
-int libpcap_open(wtap *wth)
+
+int libpcap_open(wtap *wth, int *err)
{
int bytes_read;
guint32 magic;
struct pcap_hdr hdr;
- static const int pcap_encap[] = {
- WTAP_ENCAP_NONE, /* no encapsulation */
- WTAP_ENCAP_ETHERNET,
- WTAP_ENCAP_NONE, /* 3Mb experimental Ethernet */
- WTAP_ENCAP_NONE, /* Amateur Radio AX.25 */
- WTAP_ENCAP_NONE, /* Proteon ProNET Token Ring */
- WTAP_ENCAP_NONE, /* Chaos */
- WTAP_ENCAP_TR, /* IEEE 802 Networks - assume token ring */
- WTAP_ENCAP_ARCNET,
- WTAP_ENCAP_SLIP,
- WTAP_ENCAP_PPP,
- WTAP_ENCAP_FDDI,
- WTAP_ENCAP_ATM_RFC1483,
- WTAP_ENCAP_RAW_IP
- };
- #define NUM_PCAP_ENCAPS (sizeof pcap_encap / sizeof pcap_encap[0])
- int byte_swapped = 0;
+ gboolean byte_swapped;
+ gboolean modified;
+ gboolean aix;
+ int file_encap;
/* Read in the number that should be at the start of a "libpcap" file */
- fseek(wth->fh, 0, SEEK_SET);
- bytes_read = fread(&magic, 1, sizeof magic, wth->fh);
-
+ errno = WTAP_ERR_CANT_READ;
+ bytes_read = file_read(&magic, 1, sizeof magic, wth->fh);
if (bytes_read != sizeof magic) {
- return WTAP_FILE_UNKNOWN;
+ *err = file_error(wth->fh);
+ if (*err != 0)
+ return -1;
+ return 0;
}
+ wth->data_offset += sizeof magic;
- if (magic == PCAP_SWAPPED_MAGIC) {
- /* Host that wrote it has a byte order opposite to ours. */
- magic = PCAP_MAGIC;
- byte_swapped = 1;
- }
- if (magic != PCAP_MAGIC) {
- return WTAP_FILE_UNKNOWN;
+ 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. */
- bytes_read = fread(&hdr, 1, sizeof hdr, wth->fh);
+ errno = WTAP_ERR_CANT_READ;
+ bytes_read = file_read(&hdr, 1, sizeof hdr, wth->fh);
if (bytes_read != sizeof hdr) {
- return WTAP_FILE_UNKNOWN;
+ *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. */
}
if (hdr.version_major < 2) {
/* We only support version 2.0 and later. */
- return WTAP_FILE_UNKNOWN;
+ 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;
+ }
}
- if (hdr.network >= NUM_PCAP_ENCAPS) {
- g_error("pcap: network type %d unknown", hdr.network);
- return WTAP_FILE_UNKNOWN;
+ 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->version_major = hdr.version_major;
wth->capture.pcap->version_minor = hdr.version_minor;
wth->subtype_read = libpcap_read;
- wth->file_encap = pcap_encap[hdr.network];
+ wth->subtype_seek_read = libpcap_seek_read;
+ wth->subtype_close = libpcap_close;
+ wth->file_encap = file_encap;
wth->snapshot_length = hdr.snaplen;
- return WTAP_FILE_PCAP;
+ /* 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 */
-int libpcap_read(wtap *wth)
+static gboolean libpcap_read(wtap *wth, int *err, long *data_offset)
{
- int packet_size;
- int bytes_read;
- struct pcaprec_hdr hdr;
- int 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. */
- bytes_read = fread(&hdr, 1, sizeof hdr, wth->fh);
- if (bytes_read != sizeof hdr) {
- if (bytes_read != 0) {
- g_error("pcap_read: not enough packet header data (%d bytes)",
- bytes_read);
- return -1;
+ 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 0;
+ 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);
+ 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);
}
- /* In file format version 2.3, the "incl_len" and "orig_len" fields
- were swapped, in order to match the BPF header layout.
+ /* 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;
- 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. */
- if (wth->capture.pcap->version_major == 2 &&
- (wth->capture.pcap->version_minor < 3 ||
- (wth->capture.pcap->version_minor == 3 &&
- hdr.incl_len > hdr.orig_len))) {
- guint32 temp;
+ /* Swap the "incl_len" and "orig_len" fields, if necessary. */
+ switch (wth->capture.pcap->lengths_swapped) {
+
+ case NOT_SWAPPED:
+ break;
- temp = hdr.orig_len;
- hdr.orig_len = hdr.incl_len;
- hdr.incl_len = temp;
+ 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;
}
+}
- packet_size = hdr.incl_len;
- buffer_assure_space(wth->frame_buffer, packet_size);
- data_offset = ftell(wth->fh);
- bytes_read = fread(buffer_start_ptr(wth->frame_buffer), 1,
- packet_size, wth->fh);
+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;
+}
- if (bytes_read != packet_size) {
- if (ferror(wth->fh)) {
- g_error("pcap_read: fread for data: read error\n");
- } else {
- g_error("pcap_read: fread for data: %d bytes out of %d",
- bytes_read, packet_size);
+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;
}
- return -1;
+ 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
- wth->phdr.ts.tv_sec = hdr.ts_sec;
- wth->phdr.ts.tv_usec = hdr.ts_usec;
- wth->phdr.caplen = packet_size;
- wth->phdr.len = hdr.orig_len;
- wth->phdr.pkt_encap = wth->file_encap;
+/* 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?
- return data_offset;
+ 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;
}
git.samba.org / obnox / wireshark / wip.git / blobdiff