/* * 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 lint static const char rcsid[] _U_ = "@(#) $Header: /tcpdump/master/tcpdump/print-mpls.c,v 1.13.2.1 2005/07/05 09:39:29 hannes Exp $ (LBL)"; #endif #ifdef HAVE_CONFIG_H #include "config.h" #endif #include #include #include #include #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 */ void mpls_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: */