Ethereal-dev: Re: [ethereal-dev] Re: [ethereal-users] Ethereal crash reading tcpdump '-r' file
Note: This archive is from the project's previous web site, ethereal.com. This list is no longer active.
From: Guy Harris <gharris@xxxxxxxxxxxx>
Date: Fri, 15 Sep 2000 00:50:25 -0700
On Thu, Sep 14, 2000 at 09:25:27AM -0700, Marc Solsona Palomar wrote: > Sorry guys for not replying before. yesterday was a bad day. First fo > all, you are right, the log I sent you was from a Nokia box. > I though that it was the standard tcpdump from FBSD3.4. My fault. I > really apperciate your efforts trying to help me. Thanks. Well, here's a patch to the 0.8.12 version of Ethereal that appears to allow it to read the one capture file you sent, as well as the samples of other non-standard tcpdump capture files I have. That will (unless it turns out to break other things) show up in the next release, but, as 0.8.12 just came out, the next release may not be for a while, so you may want to download the 0.8.12 source, apply the patch, and build it.
Index: wiretap/file.c
===================================================================
RCS file: /usr/local/cvsroot/ethereal/wiretap/file.c,v
retrieving revision 1.60
diff -c -r1.60 wiretap/file.c
*** wiretap/file.c 2000/08/11 13:32:36 1.60
--- wiretap/file.c 2000/09/15 07:46:43
***************
*** 267,272 ****
--- 267,276 ----
{ "modified libpcap (tcpdump)", "modlibpcap",
libpcap_dump_can_write_encap, libpcap_dump_open },
+ /* WTAP_FILE_PCAP_NOKIA */
+ { "Nokia libpcap (tcpdump)", "nokialibpcap",
+ libpcap_dump_can_write_encap, libpcap_dump_open },
+
/* WTAP_FILE_LANALYZER */
{ "Novell LANalyzer", NULL,
NULL, NULL },
Index: wiretap/libpcap.c
===================================================================
RCS file: /usr/local/cvsroot/ethereal/wiretap/libpcap.c,v
retrieving revision 1.40
diff -c -r1.40 wiretap/libpcap.c
*** wiretap/libpcap.c 2000/09/12 18:35:47 1.40
--- wiretap/libpcap.c 2000/09/15 07:46:46
***************
*** 38,44 ****
--- 38,55 ----
#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, int *data_offset);
+ 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_close(wtap *wth);
static gboolean libpcap_dump(wtap_dumper *wdh, const struct wtap_pkthdr *phdr,
***************
*** 303,311 ****
gboolean byte_swapped;
gboolean modified;
int file_encap;
- struct pcaprec_modified_hdr first_rec_hdr;
- struct pcaprec_modified_hdr second_rec_hdr;
- int hdr_len;
/* Read in the number that should be at the start of a "libpcap" file */
file_seek(wth->fh, 0, SEEK_SET);
--- 314,319 ----
***************
*** 391,397 ****
}
/* This is a libpcap file */
- wth->file_type = modified ? WTAP_FILE_PCAP_SS991029 : WTAP_FILE_PCAP;
wth->capture.pcap = g_malloc(sizeof(libpcap_t));
wth->capture.pcap->byte_swapped = byte_swapped;
wth->capture.pcap->version_major = hdr.version_major;
--- 399,404 ----
***************
*** 430,518 ****
* 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.
*/
! hdr_len = modified ? sizeof (struct pcaprec_modified_hdr) :
! sizeof (struct pcaprec_hdr);
! bytes_read = file_read(&first_rec_hdr, 1, hdr_len, wth->fh);
! if (bytes_read != hdr_len) {
! *err = file_error(wth->fh);
! if (*err != 0)
! return -1; /* failed to read it */
/*
! * Short read - assume the file isn't modified,
! * and put the seek pointer back. The attempt
! * to read the first packet will presumably get
! * the same short read.
*/
! goto give_up;
! }
! adjust_header(wth, &first_rec_hdr.hdr);
! if (first_rec_hdr.hdr.incl_len > WTAP_MAX_PACKET_SIZE) {
/*
! * The first record is bogus, so this is probably
! * a corrupt file. Assume the file has the
! * expected header type, and put the seek pointer
! * back. The attempt to read the first packet will
! * probably get the same bogus length.
*/
! goto give_up;
}
! file_seek(wth->fh,
! wth->data_offset + hdr_len + first_rec_hdr.hdr.incl_len, SEEK_SET);
! bytes_read = file_read(&second_rec_hdr, 1, hdr_len, wth->fh);
/*
! * OK, does the next packet's header look sane?
*/
! if (bytes_read != hdr_len) {
! *err = file_error(wth->fh);
! if (*err != 0)
! return -1; /* failed to read it */
/*
! * Short read - assume the file has the expected
! * header type, and put the seek pointer back. The
! * attempt to read the second packet will presumably get
! * the same short read error.
*/
! goto give_up;
}
! adjust_header(wth, &second_rec_hdr.hdr);
! if (second_rec_hdr.hdr.incl_len > WTAP_MAX_PACKET_SIZE) {
/*
! * Oh, dear. 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 treating it as having the other type for
! * the magic number it had; if that doesn't work,
! * it probably *is* a corrupt file.
*/
! wth->file_type = modified ? WTAP_FILE_PCAP_SS990915 :
! WTAP_FILE_PCAP_SS990417;
}
- give_up:
/*
! * Restore the seek pointer.
*/
! file_seek(wth->fh, wth->data_offset, SEEK_SET);
!
! return 1;
}
/* Read the next packet */
static gboolean libpcap_read(wtap *wth, int *err, int *data_offset)
{
- guint packet_size;
- int bytes_to_read, bytes_read;
struct pcaprec_ss990915_hdr hdr;
/* Read record header. */
errno = WTAP_ERR_CANT_READ;
switch (wth->file_type) {
--- 437,698 ----
* 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.
! */
! return -1;
!
! case THIS_FORMAT:
! /*
! * Well, it looks as if it might be 991029.
! * Put the seek pointer back, and return success.
! */
! file_seek(wth->fh, wth->data_offset, SEEK_SET);
! 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;
! file_seek(wth->fh, wth->data_offset, SEEK_SET);
! } 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.
! */
! 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.
! */
! file_seek(wth->fh, wth->data_offset, SEEK_SET);
! 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;
! file_seek(wth->fh, wth->data_offset, SEEK_SET);
! switch (libpcap_try(wth, err)) {
!
! case BAD_READ:
! /*
! * Well, we couldn't even read it.
! * Give up.
! */
! return -1;
!
! case THIS_FORMAT:
! /*
! * Well, it looks as if it might be ss990417.
! * Put the seek pointer back, and return success.
! */
! file_seek(wth->fh, wth->data_offset, SEEK_SET);
! 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;
! file_seek(wth->fh, wth->data_offset, SEEK_SET);
}
! 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 == WTAP_ERR_SHORT_READ) {
+ /*
+ * Short read - assume the file is in this format.
+ * When our client tries to read the first packet
+ * they will presumably get the same 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.
+ */
+ file_seek(wth->fh, first_rec_hdr.hdr.incl_len, SEEK_CUR);
! /*
! * Now attempt to read the second record's header.
! */
! if (libpcap_read_header(wth, err, &second_rec_hdr, TRUE) == -1) {
! if (*err == WTAP_ERR_SHORT_READ) {
! /*
! * Short read - assume the file is in this format.
! * When our client tries to read the second packet
! * they will presumably get the same 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, int *data_offset)
{
struct pcaprec_ss990915_hdr hdr;
+ guint packet_size;
+ int bytes_read;
+
+ 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;
+
+ buffer_assure_space(wth->frame_buffer, packet_size);
+ *data_offset = wth->data_offset;
+ errno = WTAP_ERR_CANT_READ;
+ bytes_read = file_read(buffer_start_ptr(wth->frame_buffer), 1,
+ packet_size, wth->fh);
+ if (bytes_read != packet_size) {
+ *err = file_error(wth->fh);
+ if (*err == 0)
+ *err = WTAP_ERR_SHORT_READ;
+ return FALSE;
+ }
+ 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 = hdr.hdr.orig_len;
+ wth->phdr.pkt_encap = wth->file_encap;
+
+ 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) {
***************
*** 530,584 ****
bytes_to_read = sizeof (struct pcaprec_ss990915_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 FALSE;
}
- wth->data_offset += bytes_read;
! adjust_header(wth, &hdr.hdr);
! packet_size = hdr.hdr.incl_len;
! if (packet_size > WTAP_MAX_PACKET_SIZE) {
/*
! * Probably a corrupt capture file; don't blow up trying
! * to allocate space for an immensely-large packet.
*/
! g_message("pcap: File has %u-byte packet, bigger than maximum of %u",
! packet_size, WTAP_MAX_PACKET_SIZE);
*err = WTAP_ERR_BAD_RECORD;
! return FALSE;
}
-
- buffer_assure_space(wth->frame_buffer, packet_size);
- *data_offset = wth->data_offset;
- errno = WTAP_ERR_CANT_READ;
- bytes_read = file_read(buffer_start_ptr(wth->frame_buffer), 1,
- packet_size, wth->fh);
! if (bytes_read != packet_size) {
! *err = file_error(wth->fh);
! if (*err == 0)
! *err = WTAP_ERR_SHORT_READ;
! return FALSE;
}
- 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 = hdr.hdr.orig_len;
- wth->phdr.pkt_encap = wth->file_encap;
! return TRUE;
}
static void
--- 710,769 ----
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
***************
*** 680,685 ****
--- 865,871 ----
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;
***************
*** 776,781 ****
--- 962,976 ----
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:
Index: wiretap/libpcap.h
===================================================================
RCS file: /usr/local/cvsroot/ethereal/wiretap/libpcap.h,v
retrieving revision 1.9
diff -c -r1.9 wiretap/libpcap.h
*** wiretap/libpcap.h 2000/08/11 13:32:35 1.9
--- wiretap/libpcap.h 2000/09/15 07:46:46
***************
*** 86,91 ****
--- 86,97 ----
guint8 pad[3]; /* pad to a 4-byte boundary */
};
+ /* "libpcap" record header for version used on some Nokia boxes (firewalls?) */
+ struct pcaprec_nokia_hdr {
+ struct pcaprec_hdr hdr; /* the regular header */
+ guint8 stuff[4]; /* mysterious stuff */
+ };
+
int libpcap_open(wtap *wth, int *err);
gboolean libpcap_dump_open(wtap_dumper *wdh, int *err);
int libpcap_dump_can_write_encap(int filetype, int encap);
Index: wiretap/wtap.h
===================================================================
RCS file: /usr/local/cvsroot/ethereal/wiretap/wtap.h,v
retrieving revision 1.78
diff -c -r1.78 wiretap/wtap.h
*** wiretap/wtap.h 2000/09/07 05:34:23 1.78
--- wiretap/wtap.h 2000/09/15 07:46:47
***************
*** 98,131 ****
#define WTAP_NUM_ENCAP_TYPES 17
/* File types that can be read by wiretap.
! We may eventually support writing some or all of these file types,
! too, so we distinguish between different versions of them. */
#define WTAP_FILE_UNKNOWN 0
#define WTAP_FILE_WTAP 1
#define WTAP_FILE_PCAP 2
#define WTAP_FILE_PCAP_SS990417 3
#define WTAP_FILE_PCAP_SS990915 4
#define WTAP_FILE_PCAP_SS991029 5
! #define WTAP_FILE_LANALYZER 6
! #define WTAP_FILE_NGSNIFFER_UNCOMPRESSED 7
! #define WTAP_FILE_NGSNIFFER_COMPRESSED 8
! #define WTAP_FILE_SNOOP 9
! #define WTAP_FILE_IPTRACE_1_0 10
! #define WTAP_FILE_IPTRACE_2_0 11
! #define WTAP_FILE_NETMON_1_x 12
! #define WTAP_FILE_NETMON_2_x 13
! #define WTAP_FILE_NETXRAY_1_0 14
! #define WTAP_FILE_NETXRAY_1_1 15
! #define WTAP_FILE_NETXRAY_2_00x 16
! #define WTAP_FILE_RADCOM 17
! #define WTAP_FILE_ASCEND 18
! #define WTAP_FILE_NETTL 19
! #define WTAP_FILE_TOSHIBA 20
! #define WTAP_FILE_I4BTRACE 21
! #define WTAP_FILE_CSIDS 22
/* last WTAP_FILE_ value + 1 */
! #define WTAP_NUM_FILE_TYPES 23
/*
* Maximum packet size we'll support.
--- 98,132 ----
#define WTAP_NUM_ENCAP_TYPES 17
/* File types that can be read by wiretap.
! We support writing some many of these file types, too, so we
! distinguish between different versions of them. */
#define WTAP_FILE_UNKNOWN 0
#define WTAP_FILE_WTAP 1
#define WTAP_FILE_PCAP 2
#define WTAP_FILE_PCAP_SS990417 3
#define WTAP_FILE_PCAP_SS990915 4
#define WTAP_FILE_PCAP_SS991029 5
! #define WTAP_FILE_PCAP_NOKIA 6
! #define WTAP_FILE_LANALYZER 7
! #define WTAP_FILE_NGSNIFFER_UNCOMPRESSED 8
! #define WTAP_FILE_NGSNIFFER_COMPRESSED 9
! #define WTAP_FILE_SNOOP 10
! #define WTAP_FILE_IPTRACE_1_0 11
! #define WTAP_FILE_IPTRACE_2_0 12
! #define WTAP_FILE_NETMON_1_x 13
! #define WTAP_FILE_NETMON_2_x 14
! #define WTAP_FILE_NETXRAY_1_0 15
! #define WTAP_FILE_NETXRAY_1_1 16
! #define WTAP_FILE_NETXRAY_2_00x 17
! #define WTAP_FILE_RADCOM 18
! #define WTAP_FILE_ASCEND 19
! #define WTAP_FILE_NETTL 20
! #define WTAP_FILE_TOSHIBA 21
! #define WTAP_FILE_I4BTRACE 22
! #define WTAP_FILE_CSIDS 23
/* last WTAP_FILE_ value + 1 */
! #define WTAP_NUM_FILE_TYPES 24
/*
* Maximum packet size we'll support.
- Follow-Ups:
- References:
- Re: [ethereal-dev] Re: [ethereal-users] Ethereal crash reading tcpdump '-r' file (FreeBSD 3.4)
- From: Gilbert Ramirez
- Re: [ethereal-dev] Re: [ethereal-users] Ethereal crash reading tcpdump '-r' file (FreeBSD 3.4)
- From: Guy Harris
- Re: [ethereal-dev] Re: [ethereal-users] Ethereal crash reading tcpdump '-r' file (FreeBSD 3.4)
- From: Guy Harris
- Re: [ethereal-dev] Re: [ethereal-users] Ethereal crash reading tcpdump '-r' file (FreeBSD 3.4)
- From: Marc Solsona Palomar
- Re: [ethereal-dev] Re: [ethereal-users] Ethereal crash reading tcpdump '-r' file (FreeBSD 3.4)
- Prev by Date: Re: [ethereal-dev] ECN = Explicit Congestion Notification
- Next by Date: Re: [ethereal-dev] Ethereal and H.323 dissector possible license solution
- Previous by thread: Re: [ethereal-dev] Re: [ethereal-users] Ethereal crash reading tcpdump '-r' file (FreeBSD 3.4)
- Next by thread: Re: [ethereal-dev] Re: [ethereal-users] Ethereal crash reading tcpdump '-r' file (FreeBSD 3.4)
- Index(es):





