/* * 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 * * $FreeBSD$ */ #ifndef lint static const char rcsid[] _U_ = "@(#) $Header: /tcpdump/master/tcpdump/print-llc.c,v 1.61.2.4 2005/04/26 07:27:16 guy Exp $"; #endif #ifdef HAVE_CONFIG_H #include "config.h" #endif #include #include #include #include "interface.h" #include "addrtoname.h" #include "extract.h" /* must come after interface.h */ #include "llc.h" #include "ethertype.h" #include "oui.h" static 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_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 struct tok cmd2str[] = { { 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 cisco_values[] = { { PID_CISCO_CDP, "CDP" }, { 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 }, }; 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, ssap; u_int16_t control; int is_u; register int ret; if (caplen < 3) { (void)printf("[|llc]"); default_print((u_char *)p, caplen); return(0); } dsap = *p; ssap = *(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 == LLCSAP_GLOBAL && dsap == 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); } if (eflag) { if (is_u) { printf("LLC, dsap %s (0x%02x), ssap %s (0x%02x), cmd 0x%02x: ", tok2str(llc_values, "Unknown", dsap), dsap, tok2str(llc_values, "Unknown", ssap), ssap, control); } else { printf("LLC, dsap %s (0x%02x), ssap %s (0x%02x), cmd 0x%04x: ", tok2str(llc_values, "Unknown", dsap), dsap, tok2str(llc_values, "Unknown", ssap), ssap, 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. */ printf("(NOV-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, extracted_ethertype, 2); if (ret) return (ret); } if (!eflag) { if ((ssap & ~LLC_GSAP) == dsap) { if (esrc == NULL || edst == NULL) (void)printf("%s ", llcsap_string(dsap)); else (void)printf("%s > %s %s ", etheraddr_string(esrc), etheraddr_string(edst), llcsap_string(dsap)); } else { if (esrc == NULL || edst == NULL) (void)printf("%s > %s ", llcsap_string(ssap & ~LLC_GSAP), llcsap_string(dsap)); else (void)printf("%s %s > %s %s ", etheraddr_string(esrc), llcsap_string(ssap & ~LLC_GSAP), etheraddr_string(edst), llcsap_string(dsap)); } } if (is_u) { const char *m; char f; m = tok2str(cmd2str, "%02x", LLC_U_CMD(control)); switch ((ssap & LLC_GSAP) | (control & LLC_U_POLL)) { case 0: f = 'C'; break; case LLC_GSAP: f = 'R'; break; case LLC_U_POLL: f = 'P'; break; case LLC_GSAP|LLC_U_POLL: f = 'F'; break; default: f = '?'; break; } printf("%s/%c", m, f); 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 { char f; switch ((ssap & LLC_GSAP) | (control & LLC_IS_POLL)) { case 0: f = 'C'; break; case LLC_GSAP: f = 'R'; break; case LLC_IS_POLL: f = 'P'; break; case LLC_GSAP|LLC_IS_POLL: f = 'F'; break; default: f = '?'; break; } if ((control & LLC_S_FMT) == LLC_S_FMT) { static const char *llc_s[] = { "rr", "rej", "rnr", "03" }; (void)printf("%s (r=%d,%c)", llc_s[LLC_S_CMD(control)], LLC_IS_NR(control), f); } else { (void)printf("I (s=%d,r=%d,%c)", LLC_I_NS(control), LLC_IS_NR(control), f); } p += 4; length -= 4; caplen -= 4; } return(1); } int snap_print(const u_char *p, u_int length, u_int caplen, u_short *extracted_ethertype, 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; 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 = ether_encap_print(et, p, length, caplen, extracted_ethertype); 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 = ether_encap_print(et, p, length, caplen, extracted_ethertype); if (ret) return (ret); } break; case OUI_CISCO: if (et == PID_CISCO_CDP) { cdp_print(p, length, caplen); return (1); } 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(p, length, caplen); 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: */