/* * Copyright (C) 2001 WIDE Project.  All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright *    notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright *    notice, this list of conditions and the following disclaimer in the *    documentation and/or other materials provided with the distribution. * 3. Neither the name of the project 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 BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */#ifndef lintstatic const char rcsid[] _U_ =    "@(#) $Header: /tcpdump/master/tcpdump/print-mpls.c,v 1.14 2005-07-05 09:38:19 hannes Exp $ (LBL)";#endif#ifdef HAVE_CONFIG_H#include "config.h"#endif#include <tcpdump-stdinc.h>#include <stdio.h>#include <stdlib.h>#include <string.h>#include "addrtoname.h"#include "interface.h"#include "extract.h"			/* must come after interface.h */#include "mpls.h"static const char *mpls_labelname[] = {/*0*/	"IPv4 explicit NULL", "router alert", "IPv6 explicit NULL",	"implicit NULL", "rsvd",/*5*/	"rsvd", "rsvd", "rsvd", "rsvd", "rsvd",/*10*/	"rsvd", "rsvd", "rsvd", "rsvd", "rsvd",/*15*/	"rsvd",};/* * RFC3032: MPLS label stack encoding */voidmpls_print(const u_char *bp, u_int length){	const u_char *p;	u_int32_t label_entry;        u_int16_t label_stack_depth = 0;	p = bp;	printf("MPLS");	do {		TCHECK2(*p, sizeof(label_entry));		label_entry = EXTRACT_32BITS(p);		printf("%s(label %u",                       label_stack_depth ? "\n\t" : " ",                       MPLS_LABEL(label_entry));                label_stack_depth++;		if (vflag &&		    MPLS_LABEL(label_entry) < sizeof(mpls_labelname) / sizeof(mpls_labelname[0]))			printf(" (%s)", mpls_labelname[MPLS_LABEL(label_entry)]);		printf(", exp %u", MPLS_EXP(label_entry));		if (MPLS_STACK(label_entry))			printf(", [S]");		printf(", ttl %u)", MPLS_TTL(label_entry));		p += sizeof(label_entry);	} while (!MPLS_STACK(label_entry));	switch (MPLS_LABEL(label_entry)) {	case 0:	/* IPv4 explicit NULL label */        case 3:	/* IPv4 implicit NULL label */                if (vflag>0) {                        printf("\n\t");                        ip_print(gndo, p, length - (p - bp));                }                else printf(", IP, length: %u",length);		break;#ifdef INET6	case 2:	/* IPv6 explicit NULL label */                if (vflag>0) {                        printf("\n\t");                        ip6_print(p, length - (p - bp));                }                else printf(", IPv6, length: %u",length);		break;#endif	default:		/*		 * Generally there's no indication of protocol in MPLS label		 * encoding, however draft-hsmit-isis-aal5mux-00.txt describes                 * a technique that looks at the first payload byte if the BOS (bottom of stack)                 * bit is set and tries to determine the network layer protocol                 * 0x45-0x4f is IPv4                 * 0x60-0x6f is IPv6                 * 0x81-0x83 is OSI (CLNP,ES-IS,IS-IS)                 * this technique is sometimes known as NULL encapsulation                 * and decoding is particularly useful for control-plane traffic [BGP]                 * which cisco by default sends MPLS encapsulated		 */                if (MPLS_STACK(label_entry)) { /* only do this if the stack bit is set */                    switch(*p) {                    case 0x45:                    case 0x46:                    case 0x47:                    case 0x48:                    case 0x49:                    case 0x4a:                    case 0x4b:                    case 0x4c:                    case 0x4d:                    case 0x4e:                    case 0x4f:		        if (vflag>0) {                            printf("\n\t");                            ip_print(gndo, p, length - (p - bp));			    }                        else printf(", IP, length: %u",length);                        break;#ifdef INET6                    case 0x60:                    case 0x61:                    case 0x62:                    case 0x63:                    case 0x64:                    case 0x65:                    case 0x66:                    case 0x67:                    case 0x68:                    case 0x69:                    case 0x6a:                    case 0x6b:                    case 0x6c:                    case 0x6d:                    case 0x6e:                    case 0x6f:		        if (vflag>0) {                            printf("\n\t");                            ip6_print(p, length - (p - bp));                            }			else printf(", IPv6, length: %u",length);                        break;#endif                    case 0x81:                    case 0x82:                    case 0x83:		        if (vflag>0) {                            printf("\n\t");                            isoclns_print(p, length - (p - bp), length - (p - bp));			    }			else printf(", OSI, length: %u",length);                        break;                    default:                        /* ok bail out - we did not figure out what it is*/                        break;                    }                }                return;	}trunc:	printf("[|MPLS]");}/* * Local Variables: * c-style: whitesmith * c-basic-offset: 8 * End: */