void
capture_raw(const guchar *pd, int len, packet_counts *ld)
{
/* So far, the only time we get raw connection types are with Linux and
* Irix PPP connections. We can't tell what type of data is coming down
* the line, so our safest bet is IP. - GCC
*/
/* Currently, the Linux 2.1.xxx PPP driver passes back some of the header
* sometimes. This check should be removed when 2.2 is out.
*/
if (BYTES_ARE_IN_FRAME(0,len,2) && pd[0] == 0xff && pd[1] == 0x03) {
capture_ppp_hdlc(pd, 0, len, ld);
}
/* The Linux ISDN driver sends a fake MAC address before the PPP header
* on its ippp interfaces... */
else if (BYTES_ARE_IN_FRAME(0,len,8) && pd[6] == 0xff && pd[7] == 0x03) {
capture_ppp_hdlc(pd, 6, len, ld);
}
/* ...except when it just puts out one byte before the PPP header... */
else if (BYTES_ARE_IN_FRAME(0,len,3) && pd[1] == 0xff && pd[2] == 0x03) {
capture_ppp_hdlc(pd, 1, len, ld);
}
/* ...and if the connection is currently down, it sends 10 bytes of zeroes
* instead of a fake MAC address and PPP header. */
else if (BYTES_ARE_IN_FRAME(0,len,10) && memcmp(pd, zeroes, 10) == 0) {
capture_ip(pd, 10, len, ld);
}
else {
/*
* OK, is this IPv4 or IPv6?
*/
if (BYTES_ARE_IN_FRAME(0,len,1)) {
switch (pd[0] & 0xF0) {
case 0x40:
/* IPv4 */
capture_ip(pd, 0, len, ld);
break;
#if 0
case 0x60:
/* IPv6 */
capture_ipv6(pd, 0, len, ld);
break;
#endif
}
}
}
}
void
capture_sll(const guchar *pd, int len, packet_counts *ld)
{
guint16 protocol;
if (!BYTES_ARE_IN_FRAME(0, len, SLL_HEADER_SIZE)) {
ld->other++;
return;
}
protocol = pntohs(&pd[14]);
if (protocol <= 1536) { /* yes, 1536 - that's how Linux does it */
/*
* "proto" is *not* a length field, it's a Linux internal
* protocol type.
*/
switch (protocol) {
case LINUX_SLL_P_802_2:
/*
* 802.2 LLC.
*/
capture_llc(pd, len, SLL_HEADER_SIZE, ld);
break;
case LINUX_SLL_P_ETHERNET:
/*
* Ethernet.
*/
capture_eth(pd, SLL_HEADER_SIZE, len, ld);
break;
case LINUX_SLL_P_802_3:
/*
* Novell IPX inside 802.3 with no 802.2 LLC
* header.
*/
capture_ipx(ld);
break;
case LINUX_SLL_P_PPPHDLC:
/*
* PPP HDLC.
*/
capture_ppp_hdlc(pd, len, SLL_HEADER_SIZE, ld);
break;
default:
ld->other++;
break;
}
} else
capture_ethertype(protocol, pd, SLL_HEADER_SIZE, len, ld);
}
static void
capture_info_packet(packet_counts *counts, gint wtap_linktype, const guchar *pd, guint32 caplen, union wtap_pseudo_header *pseudo_header)
{
counts->total++;
switch (wtap_linktype) {
case WTAP_ENCAP_ETHERNET:
capture_eth(pd, 0, caplen, counts);
break;
case WTAP_ENCAP_FDDI:
case WTAP_ENCAP_FDDI_BITSWAPPED:
capture_fddi(pd, caplen, counts);
break;
case WTAP_ENCAP_IEEE_802_11_PRISM:
capture_prism(pd, 0, caplen, counts);
break;
case WTAP_ENCAP_TOKEN_RING:
capture_tr(pd, 0, caplen, counts);
break;
case WTAP_ENCAP_NULL:
capture_null(pd, caplen, counts);
break;
case WTAP_ENCAP_PPP:
capture_ppp_hdlc(pd, 0, caplen, counts);
break;
case WTAP_ENCAP_RAW_IP:
capture_raw(pd, caplen, counts);
break;
case WTAP_ENCAP_SLL:
capture_sll(pd, caplen, counts);
break;
case WTAP_ENCAP_LINUX_ATM_CLIP:
capture_clip(pd, caplen, counts);
break;
case WTAP_ENCAP_IEEE_802_11:
case WTAP_ENCAP_IEEE_802_11_WITH_RADIO:
capture_ieee80211(pd, 0, caplen, counts);
break;
case WTAP_ENCAP_IEEE_802_11_RADIOTAP:
capture_radiotap(pd, 0, caplen, counts);
break;
case WTAP_ENCAP_IEEE_802_11_AVS:
capture_wlancap(pd, 0, caplen, counts);
break;
case WTAP_ENCAP_CHDLC:
capture_chdlc(pd, 0, caplen, counts);
break;
case WTAP_ENCAP_LOCALTALK:
capture_llap(counts);
break;
case WTAP_ENCAP_ATM_PDUS:
capture_atm(pseudo_header, pd, caplen, counts);
break;
case WTAP_ENCAP_IP_OVER_FC:
capture_ipfc(pd, caplen, counts);
break;
case WTAP_ENCAP_ARCNET:
capture_arcnet(pd, caplen, counts, FALSE, TRUE);
break;
case WTAP_ENCAP_ARCNET_LINUX:
capture_arcnet(pd, caplen, counts, TRUE, FALSE);
break;
case WTAP_ENCAP_APPLE_IP_OVER_IEEE1394:
capture_ap1394(pd, 0, caplen, counts);
break;
case WTAP_ENCAP_FRELAY:
case WTAP_ENCAP_FRELAY_WITH_PHDR:
capture_fr(pd, 0, caplen, counts);
break;
case WTAP_ENCAP_ENC:
capture_enc(pd, caplen, counts);
break;
case WTAP_ENCAP_PPI:
capture_ppi(pd, caplen, counts);
break;
case WTAP_ENCAP_I2C:
capture_i2c(pseudo_header, counts);
break;
case WTAP_ENCAP_AX25_KISS:
capture_ax25_kiss(pd, 0, caplen, counts);
break;
case WTAP_ENCAP_AX25:
capture_ax25(pd, 0, caplen, counts);
break;
/* XXX - some ATM drivers on FreeBSD might prepend a 4-byte ATM
pseudo-header to DLT_ATM_RFC1483, with LLC header following;
we might have to implement that at some point. */
}
}
void
capture_null( const guchar *pd, int len, packet_counts *ld )
{
guint32 null_header;
/*
* BSD drivers that use DLT_NULL - including the FreeBSD 3.2 ISDN-for-BSD
* drivers, as well as the 4.4-Lite and FreeBSD loopback drivers -
* stuff the AF_ value for the protocol, in *host* byte order, in the
* first four bytes. (BSD drivers that use DLT_LOOP, such as recent
* OpenBSD loopback drivers, stuff it in *network* byte order in the
* first four bytes.)
*
* However, the IRIX and UNICOS/mp snoop socket mechanism supplies,
* on loopback devices, a 4-byte header that has a 2 byte (big-endian)
* AF_ value and 2 bytes of 0, so it's
*
* 0000AAAA
*
* when read on a little-endian machine and
*
* AAAA0000
*
* when read on a big-endian machine. The current CVS version of libpcap
* compensates for this by converting it to standard 4-byte format before
* processing the packet, but snoop captures from IRIX or UNICOS/mp
* have the 2-byte+2-byte header, as might tcpdump or libpcap captures
* with older versions of libpcap.
*
* AF_ values are small integers, and probably fit in 8 bits (current
* values on the BSDs do), and have their upper 24 bits zero.
* This means that, in practice, if you look at the header as a 32-bit
* integer in host byte order:
*
* on a little-endian machine:
*
* a little-endian DLT_NULL header looks like
*
* 000000AA
*
* a big-endian DLT_NULL header, or a DLT_LOOP header, looks
* like
*
* AA000000
*
* an IRIX or UNICOS/mp DLT_NULL header looks like
*
* 0000AA00
*
* on a big-endian machine:
*
* a big-endian DLT_NULL header, or a DLT_LOOP header, looks
* like
*
* 000000AA
*
* a little-endian DLT_NULL header looks like
*
* AA000000
*
* an IRIX or UNICOS/mp DLT_NULL header looks like
*
* 00AA0000
*
* However, according to Gerald Combs, a FreeBSD ISDN PPP dump that
* Andreas Klemm sent to wireshark-dev has a packet type of DLT_NULL,
* and the family bits look like PPP's protocol field. (Was this an
* older, or different, ISDN driver?) Looking at what appears to be
* that capture file, it appears that it's using PPP in HDLC framing,
* RFC 1549, wherein the first two octets of the frame are 0xFF
* (address) and 0x03 (control), so the header bytes are, in order:
*
* 0xFF
* 0x03
* high-order byte of a PPP protocol field
* low-order byte of a PPP protocol field
*
* If we treat that as a 32-bit host-byte-order value, it looks like
*
* PPPP03FF
*
* where PPPP is a byte-swapped PPP protocol type if we read it on
* a little-endian machine and
*
* FF03PPPP
*
* where PPPP is a PPP protocol type if we read it on a big-endian
* machine. 0x0000 does not appear to be a valid PPP protocol type
* value, so at least one of those hex digits is guaranteed not to
* be 0.
*
* Old versions of libpcap for Linux used DLT_NULL for loopback devices,
* but not any other devices. (Current versions use DLT_EN10MB for it.)
* The Linux loopback driver puts an *Ethernet* header at the beginning
* of loopback packets, with fake source and destination addresses and
* the appropriate Ethernet type value; however, those older versions of
* libpcap for Linux compensated for this by skipping the source and
* destination MAC addresses, replacing them with 2 bytes of 0.
* This means that if we're reading the capture on a little-endian
* machine, the header, treated as a 32-bit integer, looks like
*
* EEEE0000
*
* where EEEE is a byte-swapped Ethernet type, and if we're reading it
* on a big-endian machine, it looks like
*
* 0000EEEE
*
* where EEEE is an Ethernet type.
*
* If the first 2 bytes of the header are FF 03:
*
* it can't be a big-endian BSD DLT_NULL header, or a DLT_LOOP
* header, as AF_ values are small so the first 2 bytes of the
* header would be 0;
*
* it can't be a little-endian BSD DLT_NULL header, as the
* resulting AF_ value would be >= 0x03FF, which is too big
* for an AF_ value;
*
* it can't be an IRIX or UNICOS/mp DLT_NULL header, as the
* resulting AF_ value with be 0x03FF.
*
* So the first thing we do is check the first two bytes of the
* header; if it's FF 03, we treat the packet as a PPP frame.
*
* Otherwise, if the upper 16 bits are non-zero, either:
*
* it's a BSD DLT_NULL or DLT_LOOP header whose AF_ value
* is not in our byte order;
*
* it's an IRIX or UNICOS/mp DLT_NULL header being read on
* a big-endian machine;
*
* it's a Linux DLT_NULL header being read on a little-endian
* machine.
*
* In all those cases except for the IRIX or UNICOS/mp DLT_NULL header,
* we should byte-swap it (if it's a Linux DLT_NULL header, that'll
* put the Ethernet type in the right byte order). In the case
* of the IRIX or UNICOS/mp DLT_NULL header, we should just get
* the upper 16 bits as an AF_ value.
*
* If it's a BSD DLT_NULL or DLT_LOOP header whose AF_ value is not
* in our byte order, then the upper 2 hex digits would be non-zero
* and the next 2 hex digits down would be zero, as AF_ values fit in
* 8 bits, and the upper 2 hex digits are the *lower* 8 bits of the value.
*
* If it's an IRIX or UNICOS/mp DLT_NULL header, the upper 2 hex digits
* would be zero and the next 2 hex digits down would be non-zero, as
* the upper 16 bits are a big-endian AF_ value. Furthermore, the
* next 2 hex digits down are likely to be < 0x60, as 0x60 is 96,
* and, so far, we're far from requiring AF_ values that high.
*
* If it's a Linux DLT_NULL header, the third hex digit from the top
* will be >= 6, as Ethernet types are >= 1536, or 0x0600, and
* it's byte-swapped, so the second 2 hex digits from the top are
* >= 0x60.
*
* So, if the upper 16 bits are non-zero:
*
* if the upper 2 hex digits are 0 and the next 2 hex digits are
* in the range 0x00-0x5F, we treat it as a big-endian IRIX or
* UNICOS/mp DLT_NULL header;
*
* otherwise, we byte-swap it and do the next stage.
*
* If the upper 16 bits are zero, either:
*
* it's a BSD DLT_NULLor DLT_LOOP header whose AF_ value is in
* our byte order;
*
* it's an IRIX or UNICOS/mp DLT_NULL header being read on
* a little-endian machine;
*
* it's a Linux DLT_NULL header being read on a big-endian
* machine.
*
* In all of those cases except for the IRIX or UNICOS/mp DLT_NULL header,
* we should *not* byte-swap it. In the case of the IRIX or UNICOS/mp
* DLT_NULL header, we should extract the AF_ value and byte-swap it.
*
* If it's a BSD DLT_NULL or DLT_LOOP header whose AF_ value is
* in our byte order, the upper 6 hex digits would all be zero.
*
* If it's an IRIX or UNICOS/mp DLT_NULL header, the upper 4 hex
* digits would be zero and the next 2 hex digits would not be zero.
* Furthermore, the third hex digit from the bottom would be <
*/
if (!BYTES_ARE_IN_FRAME(0, len, 2)) {
ld->other++;
return;
}
if (pd[0] == 0xFF && pd[1] == 0x03) {
/*
* Hand it to PPP.
*/
capture_ppp_hdlc(pd, 0, len, ld);
} else {
/*
* Treat it as a normal DLT_NULL header.
*/
if (!BYTES_ARE_IN_FRAME(0, len, (int)sizeof(null_header))) {
ld->other++;
return;
}
memcpy((char *)&null_header, (const char *)&pd[0], sizeof(null_header));
if ((null_header & 0xFFFF0000) != 0) {
/*
* It is possible that the AF_ type was only a 16 bit value.
* IRIX and UNICOS/mp loopback snoop use a 4 byte header with
* AF_ type in the first 2 bytes!
* BSD AF_ types will always have the upper 8 bits as 0.
*/
if ((null_header & 0xFF000000) == 0 &&
(null_header & 0x00FF0000) < 0x00060000) {
/*
* Looks like a IRIX or UNICOS/mp loopback header, in the
* correct byte order. Set the null header value to the
* AF_ type, which is in the upper 16 bits of "null_header".
*/
null_header >>= 16;
} else {
/* Byte-swap it. */
null_header = GUINT32_SWAP_LE_BE(null_header);
}
} else {