/*
* Copyright (c) 1992, 1993, 1994, 1995, 1996, 1997
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that: (1) source code distributions
* retain the above copyright notice and this paragraph in its entirety, (2)
* distributions including binary code include the above copyright notice and
* this paragraph in its entirety in the documentation or other materials
* provided with the distribution, and (3) all advertising materials mentioning
* features or use of this software display the following acknowledgement:
* ``This product includes software developed by the University of California,
* Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
* the University nor the names of its contributors may be used to endorse
* or promote products derived from this software without specific prior
* written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*
* Code by Matt Thomas, Digital Equipment Corporation
* with an awful lot of hacking by Jeffrey Mogul, DECWRL
*/
#ifndef lint
static const char rcsid[] _U_ =
"@(#) $Header: /tcpdump/master/tcpdump/print-llc.c,v 1.75 2007-04-13 09:43:11 hannes Exp $";
#endif
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <tcpdump-stdinc.h>
#include <stdio.h>
#include <string.h>
#include "interface.h"
#include "addrtoname.h"
#include "extract.h" /* must come after interface.h */
#include "llc.h"
#include "ethertype.h"
#include "oui.h"
static const struct tok llc_values[] = {
{ LLCSAP_NULL, "Null" },
{ LLCSAP_GLOBAL, "Global" },
{ LLCSAP_8021B_I, "802.1B I" },
{ LLCSAP_8021B_G, "802.1B G" },
{ LLCSAP_IP, "IP" },
{ LLCSAP_SNA, "SNA" },
{ LLCSAP_PROWAYNM, "ProWay NM" },
{ LLCSAP_8021D, "STP" },
{ LLCSAP_RS511, "RS511" },
{ LLCSAP_ISO8208, "ISO8208" },
{ LLCSAP_PROWAY, "ProWay" },
{ LLCSAP_SNAP, "SNAP" },
{ LLCSAP_IPX, "IPX" },
{ LLCSAP_NETBEUI, "NetBeui" },
{ LLCSAP_ISONS, "OSI" },
{ 0, NULL },
};
static const struct tok llc_cmd_values[] = {
{ LLC_UI, "ui" },
{ LLC_TEST, "test" },
{ LLC_XID, "xid" },
{ LLC_UA, "ua" },
{ LLC_DISC, "disc" },
{ LLC_DM, "dm" },
{ LLC_SABME, "sabme" },
{ LLC_FRMR, "frmr" },
{ 0, NULL }
};
static const struct tok llc_flag_values[] = {
{ 0, "Command" },
{ LLC_GSAP, "Response" },
{ LLC_U_POLL, "Poll" },
{ LLC_GSAP|LLC_U_POLL, "Final" },
{ LLC_IS_POLL, "Poll" },
{ LLC_GSAP|LLC_IS_POLL, "Final" },
{ 0, NULL }
};
static const struct tok llc_ig_flag_values[] = {
{ 0, "Individual" },
{ LLC_IG, "Group" },
{ 0, NULL }
};
static const struct tok llc_supervisory_values[] = {
{ 0, "Receiver Ready" },
{ 1, "Receiver not Ready" },
{ 2, "Reject" },
{ 0, NULL }
};
static const struct tok cisco_values[] = {
{ PID_CISCO_CDP, "CDP" },
{ PID_CISCO_VTP, "VTP" },
{ PID_CISCO_DTP, "DTP" },
{ PID_CISCO_UDLD, "UDLD" },
{ PID_CISCO_PVST, "PVST" },
{ PID_CISCO_VLANBRIDGE, "VLAN Bridge" },
{ 0, NULL }
};
static const struct tok bridged_values[] = {
{ PID_RFC2684_ETH_FCS, "Ethernet + FCS" },
{ PID_RFC2684_ETH_NOFCS, "Ethernet w/o FCS" },
{ PID_RFC2684_802_4_FCS, "802.4 + FCS" },
{ PID_RFC2684_802_4_NOFCS, "802.4 w/o FCS" },
{ PID_RFC2684_802_5_FCS, "Token Ring + FCS" },
{ PID_RFC2684_802_5_NOFCS, "Token Ring w/o FCS" },
{ PID_RFC2684_FDDI_FCS, "FDDI + FCS" },
{ PID_RFC2684_FDDI_NOFCS, "FDDI w/o FCS" },
{ PID_RFC2684_802_6_FCS, "802.6 + FCS" },
{ PID_RFC2684_802_6_NOFCS, "802.6 w/o FCS" },
{ PID_RFC2684_BPDU, "BPDU" },
{ 0, NULL },
};
static const struct tok null_values[] = {
{ 0, NULL }
};
struct oui_tok {
u_int32_t oui;
const struct tok *tok;
};
static const struct oui_tok oui_to_tok[] = {
{ OUI_ENCAP_ETHER, ethertype_values },
{ OUI_CISCO_90, ethertype_values }, /* uses some Ethertype values */
{ OUI_APPLETALK, ethertype_values }, /* uses some Ethertype values */
{ OUI_CISCO, cisco_values },
{ OUI_RFC2684, bridged_values }, /* bridged, RFC 2427 FR or RFC 2864 ATM */
{ 0, NULL }
};
/*
* Returns non-zero IFF it succeeds in printing the header
*/
int
llc_print(const u_char *p, u_int length, u_int caplen,
const u_char *esrc, const u_char *edst, u_short *extracted_ethertype)
{
u_int8_t dsap_field, dsap, ssap_field, ssap;
u_int16_t control;
int is_u;
register int ret;
*extracted_ethertype = 0;
if (caplen < 3) {
(void)printf("[|llc]");
default_print((u_char *)p, caplen);
return(0);
}
dsap_field = *p;
ssap_field = *(p + 1);
/*
* OK, what type of LLC frame is this? The length
* of the control field depends on that - I frames
* have a two-byte control field, and U frames have
* a one-byte control field.
*/
control = *(p + 2);
if ((control & LLC_U_FMT) == LLC_U_FMT) {
/*
* U frame.
*/
is_u = 1;
} else {
/*
* The control field in I and S frames is
* 2 bytes...
*/
if (caplen < 4) {
(void)printf("[|llc]");
default_print((u_char *)p, caplen);
return(0);
}
/*
* ...and is little-endian.
*/
control = EXTRACT_LE_16BITS(p + 2);
is_u = 0;
}
if (ssap_field == LLCSAP_GLOBAL && dsap_field == LLCSAP_GLOBAL) {
/*
* This is an Ethernet_802.3 IPX frame; it has an
* 802.3 header (i.e., an Ethernet header where the
* type/length field is <= ETHERMTU, i.e. it's a length
* field, not a type field), but has no 802.2 header -
* the IPX packet starts right after the Ethernet header,
* with a signature of two bytes of 0xFF (which is
* LLCSAP_GLOBAL).
*
* (It might also have been an Ethernet_802.3 IPX at
* one time, but got bridged onto another network,
* such as an 802.11 network; this has appeared in at
* least one capture file.)
*/
if (eflag)
printf("IPX 802.3: ");
ipx_print(p, length);
return (1);
}
dsap = dsap_field & ~LLC_IG;
ssap = ssap_field & ~LLC_GSAP;
if (eflag) {
printf("LLC, dsap %s (0x%02x) %s, ssap %s (0x%02x) %s",
tok2str(llc_values, "Unknown", dsap),
dsap,
tok2str(llc_ig_flag_values, "Unknown", dsap_field & LLC_IG),
tok2str(llc_values, "Unknown", ssap),
ssap,
tok2str(llc_flag_values, "Unknown", ssap_field & LLC_GSAP));
if (is_u) {
printf(", ctrl 0x%02x: ", control);
} else {
printf(", ctrl 0x%04x: ", control);
}
}
if (ssap == LLCSAP_8021D && dsap == LLCSAP_8021D &&
control == LLC_UI) {
stp_print(p+3, length-3);
return (1);
}
if (ssap == LLCSAP_IP && dsap == LLCSAP_IP &&
control == LLC_UI) {
ip_print(gndo, p+4, length-4);
return (1);
}
if (ssap == LLCSAP_IPX && dsap == LLCSAP_IPX &&
control == LLC_UI) {
/*
* This is an Ethernet_802.2 IPX frame, with an 802.3
* header and an 802.2 LLC header with the source and
* destination SAPs being the IPX SAP.
*
* Skip DSAP, LSAP, and control field.
*/
if (eflag)
printf("IPX 802.2: ");
ipx_print(p+3, length-3);
return (1);
}
#ifdef TCPDUMP_DO_SMB
if (ssap == LLCSAP_NETBEUI && dsap == LLCSAP_NETBEUI
&& (!(control & LLC_S_FMT) || control == LLC_U_FMT)) {
/*
* we don't actually have a full netbeui parser yet, but the
* smb parser can handle many smb-in-netbeui packets, which
* is very useful, so we call that
*
* We don't call it for S frames, however, just I frames
* (which are frames that don't have the low-order bit,
* LLC_S_FMT, set in the first byte of the control field)
* and UI frames (whose control field is just 3, LLC_U_FMT).
*/
/*
* Skip the LLC header.
*/
if (is_u) {
p += 3;
length -= 3;
caplen -= 3;
} else {
p += 4;
length -= 4;
caplen -= 4;
}
netbeui_print(control, p, length);
return (1);
}
#endif
if (ssap == LLCSAP_ISONS && dsap == LLCSAP_ISONS
&& control == LLC_UI) {
isoclns_print(p + 3, length - 3, caplen - 3);
return (1);
}
if (ssap == LLCSAP_SNAP && dsap == LLCSAP_SNAP
&& control == LLC_UI) {
/*
* XXX - what *is* the right bridge pad value here?
* Does anybody ever bridge one form of LAN traffic
* over a networking type that uses 802.2 LLC?
*/
ret = snap_print(p+3, length-3, caplen-3, 2);
if (ret)
return (ret);
}
if (!eflag) {
if (ssap == dsap) {
if (esrc == NULL || edst == NULL)
(void)printf("%s ", tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
else
(void)printf("%s > %s %s ",
etheraddr_string(esrc),
etheraddr_string(edst),
tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
} else {
if (esrc == NULL || edst == NULL)
(void)printf("%s > %s ",
tok2str(llc_values, "Unknown SSAP 0x%02x", ssap),
tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
else
(void)printf("%s %s > %s %s ",
etheraddr_string(esrc),
tok2str(llc_values, "Unknown SSAP 0x%02x", ssap),
etheraddr_string(edst),
tok2str(llc_values, "Unknown DSAP 0x%02x", dsap));
}
}
if (is_u) {
printf("Unnumbered, %s, Flags [%s], length %u",
tok2str(llc_cmd_values, "%02x", LLC_U_CMD(control)),
tok2str(llc_flag_values,"?",(ssap_field & LLC_GSAP) | (control & LLC_U_POLL)),
length);
p += 3;
length -= 3;
caplen -= 3;
if ((control & ~LLC_U_POLL) == LLC_XID) {
if (*p == LLC_XID_FI) {
printf(": %02x %02x", p[1], p[2]);
p += 3;
length -= 3;
caplen -= 3;
}
}
} else {
if ((control & LLC_S_FMT) == LLC_S_FMT) {
(void)printf("Supervisory, %s, rcv seq %u, Flags [%s], length %u",
tok2str(llc_supervisory_values,"?",LLC_S_CMD(control)),
LLC_IS_NR(control),
tok2str(llc_flag_values,"?",(ssap_field & LLC_GSAP) | (control & LLC_IS_POLL)),
length);
} else {
(void)printf("Information, send seq %u, rcv seq %u, Flags [%s], length %u",
LLC_I_NS(control),
LLC_IS_NR(control),
tok2str(llc_flag_values,"?",(ssap_field & LLC_GSAP) | (control & LLC_IS_POLL)),
length);
}
p += 4;
length -= 4;
caplen -= 4;
}
return(1);
}
int
snap_print(const u_char *p, u_int length, u_int caplen, u_int bridge_pad)
{
u_int32_t orgcode;
register u_short et;
register int ret;
TCHECK2(*p, 5);
orgcode = EXTRACT_24BITS(p);
et = EXTRACT_16BITS(p + 3);
if (eflag) {
const struct tok *tok = null_values;
const struct oui_tok *otp;
for (otp = &oui_to_tok[0]; otp->tok != NULL; otp++) {
if (otp->oui == orgcode) {
tok = otp->tok;
break;
}
}
(void)printf("oui %s (0x%06x), %s %s (0x%04x): ",
tok2str(oui_values, "Unknown", orgcode),
orgcode,
(orgcode == 0x000000 ? "ethertype" : "pid"),
tok2str(tok, "Unknown", et),
et);
}
p += 5;
length -= 5;
caplen -= 5;
switch (orgcode) {
case OUI_ENCAP_ETHER:
case OUI_CISCO_90:
/*
* This is an encapsulated Ethernet packet,
* or a packet bridged by some piece of
* Cisco hardware; the protocol ID is
* an Ethernet protocol type.
*/
ret = ethertype_print(gndo, et, p, length, caplen);
if (ret)
return (ret);
break;
case OUI_APPLETALK:
if (et == ETHERTYPE_ATALK) {
/*
* No, I have no idea why Apple used one
* of their own OUIs, rather than
* 0x000000, and an Ethernet packet
* type, for Appletalk data packets,
* but used 0x000000 and an Ethernet
* packet type for AARP packets.
*/
ret = ethertype_print(gndo, et, p, length, caplen);
if (ret)
return (ret);
}
break;
case OUI_CISCO:
switch (et) {
case PID_CISCO_CDP:
cdp_print(p, length, caplen);
return (1);
case PID_CISCO_DTP:
dtp_print(p, length);
return (1);
case PID_CISCO_UDLD:
udld_print(p, length);
return (1);
case PID_CISCO_VTP:
vtp_print(p, length);
return (1);
case PID_CISCO_PVST:
case PID_CISCO_VLANBRIDGE:
stp_print(p, length);
return (1);
default:
break;
}
case OUI_RFC2684:
switch (et) {
case PID_RFC2684_ETH_FCS:
case PID_RFC2684_ETH_NOFCS:
/*
* XXX - remove the last two bytes for
* PID_RFC2684_ETH_FCS?
*/
/*
* Skip the padding.
*/
TCHECK2(*p, bridge_pad);
caplen -= bridge_pad;
length -= bridge_pad;
p += bridge_pad;
/*
* What remains is an Ethernet packet.
*/
ether_print(gndo, p, length, caplen, NULL, NULL);
return (1);
case PID_RFC2684_802_5_FCS:
case PID_RFC2684_802_5_NOFCS:
/*
* XXX - remove the last two bytes for
* PID_RFC2684_ETH_FCS?
*/
/*
* Skip the padding, but not the Access
* Control field.
*/
TCHECK2(*p, bridge_pad);
caplen -= bridge_pad;
length -= bridge_pad;
p += bridge_pad;
/*
* What remains is an 802.5 Token Ring
* packet.
*/
token_print(p, length, caplen);
return (1);
case PID_RFC2684_FDDI_FCS:
case PID_RFC2684_FDDI_NOFCS:
/*
* XXX - remove the last two bytes for
* PID_RFC2684_ETH_FCS?
*/
/*
* Skip the padding.
*/
TCHECK2(*p, bridge_pad + 1);
caplen -= bridge_pad + 1;
length -= bridge_pad + 1;
p += bridge_pad + 1;
/*
* What remains is an FDDI packet.
*/
fddi_print(p, length, caplen);
return (1);
case PID_RFC2684_BPDU:
stp_print(p, length);
return (1);
}
}
return (0);
trunc:
(void)printf("[|snap]");
return (1);
}
/*
* Local Variables:
* c-style: whitesmith
* c-basic-offset: 8
* End:
*/