wtap_open_return_val libpcap_open(wtap *wth, int *err, gchar **err_info)
{
guint32 magic;
struct pcap_hdr hdr;
gboolean byte_swapped;
gboolean modified;
gboolean aix;
int file_encap;
gint64 first_packet_offset;
libpcap_t *libpcap;
static const int subtypes_modified[] = {
WTAP_FILE_TYPE_SUBTYPE_PCAP_SS991029,
WTAP_FILE_TYPE_SUBTYPE_PCAP_SS990915
};
#define N_SUBTYPES_MODIFIED G_N_ELEMENTS(subtypes_modified)
static const int subtypes_standard[] = {
WTAP_FILE_TYPE_SUBTYPE_PCAP,
WTAP_FILE_TYPE_SUBTYPE_PCAP_SS990417,
WTAP_FILE_TYPE_SUBTYPE_PCAP_NOKIA
};
#define N_SUBTYPES_STANDARD G_N_ELEMENTS(subtypes_standard)
static const int subtypes_nsec[] = {
WTAP_FILE_TYPE_SUBTYPE_PCAP_NSEC
};
#define N_SUBTYPES_NSEC G_N_ELEMENTS(subtypes_nsec)
#define MAX_FIGURES_OF_MERIT \
MAX(MAX(N_SUBTYPES_MODIFIED, N_SUBTYPES_STANDARD), N_SUBTYPES_NSEC)
int figures_of_merit[MAX_FIGURES_OF_MERIT];
const int *subtypes;
int n_subtypes;
int best_subtype;
int i;
/* Read in the number that should be at the start of a "libpcap" file */
if (!wtap_read_bytes(wth->fh, &magic, sizeof magic, err, err_info)) {
if (*err != WTAP_ERR_SHORT_READ)
return WTAP_OPEN_ERROR;
return WTAP_OPEN_NOT_MINE;
}
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;
wth->file_tsprec = WTAP_TSPREC_USEC;
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;
wth->file_tsprec = WTAP_TSPREC_USEC;
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;
wth->file_tsprec = WTAP_TSPREC_USEC;
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;
wth->file_tsprec = WTAP_TSPREC_USEC;
break;
case PCAP_NSEC_MAGIC:
/* Host that wrote it has our byte order, and was writing
the file in a format similar to standard libpcap
except that the time stamps have nanosecond resolution. */
byte_swapped = FALSE;
modified = FALSE;
wth->file_tsprec = WTAP_TSPREC_NSEC;
break;
case PCAP_SWAPPED_NSEC_MAGIC:
/* Host that wrote it out has a byte order opposite to
ours, and was writing the file in a format similar to
standard libpcap except that the time stamps have
nanosecond resolution. */
byte_swapped = TRUE;
modified = FALSE;
wth->file_tsprec = WTAP_TSPREC_NSEC;
break;
default:
/* Not a "libpcap" type we know about. */
return WTAP_OPEN_NOT_MINE;
}
/* Read the rest of the header. */
if (!wtap_read_bytes(wth->fh, &hdr, sizeof hdr, err, err_info))
return WTAP_OPEN_ERROR;
if (byte_swapped) {
/* Byte-swap the header fields about which we care. */
hdr.version_major = GUINT16_SWAP_LE_BE(hdr.version_major);
hdr.version_minor = GUINT16_SWAP_LE_BE(hdr.version_minor);
hdr.snaplen = GUINT32_SWAP_LE_BE(hdr.snaplen);
hdr.network = GUINT32_SWAP_LE_BE(hdr.network);
}
if (hdr.version_major < 2) {
/* We only support version 2.0 and later. */
*err = WTAP_ERR_UNSUPPORTED;
*err_info = g_strdup_printf("pcap: major version %u unsupported",
hdr.version_major);
return WTAP_OPEN_ERROR;
}
/*
* 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 Wireshark.
*/
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) {
*err = WTAP_ERR_UNSUPPORTED;
*err_info = g_strdup_printf("pcap: network type %u unknown or unsupported",
hdr.network);
return WTAP_OPEN_ERROR;
}
/* This is a libpcap file */
libpcap = (libpcap_t *)g_malloc(sizeof(libpcap_t));
libpcap->byte_swapped = byte_swapped;
libpcap->version_major = hdr.version_major;
libpcap->version_minor = hdr.version_minor;
wth->priv = (void *)libpcap;
wth->subtype_read = libpcap_read;
wth->subtype_seek_read = libpcap_seek_read;
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)
libpcap->lengths_swapped = SWAPPED;
else if (hdr.version_minor == 3)
libpcap->lengths_swapped = MAYBE_SWAPPED;
else
libpcap->lengths_swapped = NOT_SWAPPED;
break;
case 543:
libpcap->lengths_swapped = SWAPPED;
break;
default:
libpcap->lengths_swapped = NOT_SWAPPED;
break;
}
/*
* Is this AIX format?
*/
if (aix) {
/*
* Yes. Skip all the tests for other mutant formats,
* and for the ERF link-layer header type, and set the
* precision to nanosecond precision.
*/
wth->file_type_subtype = WTAP_FILE_TYPE_SUBTYPE_PCAP_AIX;
wth->file_tsprec = WTAP_TSPREC_NSEC;
return WTAP_OPEN_MINE;
}
/*
* 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 Wireshark 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 the subtypes for that.
*/
subtypes = subtypes_modified;
n_subtypes = N_SUBTYPES_MODIFIED;
} else {
if (wth->file_tsprec == WTAP_TSPREC_NSEC) {
/*
* We have nanosecond-format libpcap's magic
* number. Try the subtypes for that.
*/
subtypes = subtypes_nsec;
n_subtypes = N_SUBTYPES_NSEC;
} else {
/*
* We have the regular libpcap magic number.
* Try the subtypes for that.
*/
subtypes = subtypes_standard;
n_subtypes = N_SUBTYPES_STANDARD;
}
}
/*
* Try all the subtypes.
*/
first_packet_offset = file_tell(wth->fh);
for (i = 0; i < n_subtypes; i++) {
wth->file_type_subtype = subtypes[i];
figures_of_merit[i] = libpcap_try(wth, err, err_info);
if (figures_of_merit[i] == -1) {
/*
* Well, we couldn't even read it.
* Give up.
*/
return WTAP_OPEN_ERROR;
}
if (figures_of_merit[i] == 0) {
/*
* This format doesn't have any issues.
* Put the seek pointer back, and finish.
*/
if (file_seek(wth->fh, first_packet_offset, SEEK_SET, err) == -1) {
return WTAP_OPEN_ERROR;
}
goto done;
}
/*
* OK, we've recorded the figure of merit for this one;
* go back to the first packet and try the next one.
*/
if (file_seek(wth->fh, first_packet_offset, SEEK_SET, err) == -1) {
return WTAP_OPEN_ERROR;
}
}
/*
* OK, none are perfect; let's see which one is least bad.
*/
best_subtype = INT_MAX;
for (i = 0; i < n_subtypes; i++) {
/*
* Is this subtype better than the last one we saw?
*/
if (figures_of_merit[i] < best_subtype) {
/*
* Yes. Choose it until we find a better one.
*/
wth->file_type_subtype = subtypes[i];
best_subtype = figures_of_merit[i];
}
}
done:
/*
* We treat a DLT_ value of 13 specially - it appears that in
* Nokia libpcap format, it's some form of ATM with what I
* suspect is a pseudo-header (even though Nokia's IPSO is
* based on FreeBSD, which #defines DLT_SLIP_BSDOS as 13).
*
* If this is a Nokia capture, treat 13 as WTAP_ENCAP_ATM_PDUS,
* rather than as what we normally treat it.
*/
if (wth->file_type_subtype == WTAP_FILE_TYPE_SUBTYPE_PCAP_NOKIA &&
hdr.network == 13)
wth->file_encap = WTAP_ENCAP_ATM_PDUS;
if (wth->file_encap == WTAP_ENCAP_ERF) {
/*
* Populate set of interface IDs for ERF format.
* Currently, this *has* to be done at open time.
*/
erf_populate_interfaces(wth);
}
return WTAP_OPEN_MINE;
}
int libpcap_open(wtap *wth, int *err, gchar **err_info)
{
int bytes_read;
guint32 magic;
struct pcap_hdr hdr;
gboolean byte_swapped;
gboolean modified;
gboolean aix;
int file_encap;
libpcap_t *libpcap;
/* Read in the number that should be at the start of a "libpcap" file */
errno = WTAP_ERR_CANT_READ;
bytes_read = file_read(&magic, sizeof magic, wth->fh);
if (bytes_read != sizeof magic) {
*err = file_error(wth->fh, err_info);
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;
wth->tsprecision = WTAP_FILE_TSPREC_USEC;
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;
wth->tsprecision = WTAP_FILE_TSPREC_USEC;
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;
wth->tsprecision = WTAP_FILE_TSPREC_USEC;
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;
wth->tsprecision = WTAP_FILE_TSPREC_USEC;
break;
case PCAP_NSEC_MAGIC:
/* Host that wrote it has our byte order, and was writing
the file in a format similar to standard libpcap
except that the time stamps have nanosecond resolution. */
byte_swapped = FALSE;
modified = FALSE;
wth->tsprecision = WTAP_FILE_TSPREC_NSEC;
break;
case PCAP_SWAPPED_NSEC_MAGIC:
/* Host that wrote it out has a byte order opposite to
ours, and was writing the file in a format similar to
standard libpcap except that the time stamps have
nanosecond resolution. */
byte_swapped = TRUE;
modified = FALSE;
wth->tsprecision = WTAP_FILE_TSPREC_NSEC;
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, sizeof hdr, wth->fh);
if (bytes_read != sizeof hdr) {
*err = file_error(wth->fh, err_info);
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. */
*err = WTAP_ERR_UNSUPPORTED;
*err_info = g_strdup_printf("pcap: major version %u unsupported",
hdr.version_major);
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 Wireshark.
*/
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) {
*err = WTAP_ERR_UNSUPPORTED_ENCAP;
*err_info = g_strdup_printf("pcap: network type %u unknown or unsupported",
hdr.network);
return -1;
}
/* This is a libpcap file */
libpcap = (libpcap_t *)g_malloc(sizeof(libpcap_t));;
libpcap->byte_swapped = byte_swapped;
libpcap->version_major = hdr.version_major;
libpcap->version_minor = hdr.version_minor;
wth->priv = (void *)libpcap;
wth->subtype_read = libpcap_read;
wth->subtype_seek_read = libpcap_seek_read;
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)
libpcap->lengths_swapped = SWAPPED;
else if (hdr.version_minor == 3)
libpcap->lengths_swapped = MAYBE_SWAPPED;
else
libpcap->lengths_swapped = NOT_SWAPPED;
break;
case 543:
libpcap->lengths_swapped = SWAPPED;
break;
default:
libpcap->lengths_swapped = NOT_SWAPPED;
break;
}
/*
* Is this AIX format?
*/
if (aix) {
/*
* Yes. Skip all the tests for other mutant formats,
* and set the precision to nanosecond precision.
*/
wth->file_type = WTAP_FILE_PCAP_AIX;
wth->tsprecision = WTAP_FILE_TSPREC_NSEC;
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 Wireshark 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->priv);
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->priv);
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->priv);
return -1;
}
} else {
/*
* Well, we have the standard magic number.
*
* Try the standard format first.
*/
if(wth->tsprecision == WTAP_FILE_TSPREC_NSEC) {
wth->file_type = WTAP_FILE_PCAP_NSEC;
} else {
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->priv);
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->priv);
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->priv);
return -1;
}
switch (libpcap_try(wth, err)) {
case BAD_READ:
/*
* Well, we couldn't even read it.
* Give up.
*/
g_free(wth->priv);
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->priv);
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->priv);
return -1;
}
}
/*
* We treat a DLT_ value of 13 specially - it appears that in
* Nokia libpcap format, it's some form of ATM with what I
* suspect is a pseudo-header (even though Nokia's IPSO is
* based on FreeBSD, which #defines DLT_SLIP_BSDOS as 13).
*
* If this is a Nokia capture, treat 13 as WTAP_ENCAP_ATM_PDUS,
* rather than as what we normally treat it.
*/
if (wth->file_type == WTAP_FILE_PCAP_NOKIA && hdr.network == 13)
wth->file_encap = WTAP_ENCAP_ATM_PDUS;
return 1;
}
