1 /* 2 * Copyright (C) 2001 WIDE Project. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 3. Neither the name of the project nor the names of its contributors 13 * may be used to endorse or promote products derived from this software 14 * without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #ifndef lint 30 static const char rcsid[] = 31 "@(#) $Header: /tcpdump/master/tcpdump/print-mpls.c,v 1.2 2001/06/26 06:24:57 guy Exp $ (LBL)"; 32 #endif 33 34 #ifdef HAVE_CONFIG_H 35 #include "config.h" 36 #endif 37 38 #include <sys/param.h> 39 #include <sys/time.h> 40 #include <sys/socket.h> 41 42 #include <netinet/in.h> 43 44 #include <stdio.h> 45 #include <stdlib.h> 46 #include <string.h> 47 #include <unistd.h> 48 49 #include "addrtoname.h" 50 #include "interface.h" 51 #include "extract.h" /* must come after interface.h */ 52 53 #define LABEL_MASK 0xfffff000 54 #define LABEL_SHIFT 12 55 #define EXP_MASK 0x00000e00 56 #define EXP_SHIFT 9 57 #define STACK_MASK 0x00000100 58 #define STACK_SHIFT 8 59 #define TTL_MASK 0x000000ff 60 #define TTL_SHIFT 0 61 62 #define MPLS_LABEL(x) (((x) & LABEL_MASK) >> LABEL_SHIFT) 63 #define MPLS_EXP(x) (((x) & EXP_MASK) >> EXP_SHIFT) 64 #define MPLS_STACK(x) (((x) & STACK_MASK) >> STACK_SHIFT) 65 #define MPLS_TTL(x) (((x) & TTL_MASK) >> TTL_SHIFT) 66 67 static const char *mpls_labelname[] = { 68 /*0*/ "IPv4 explicit NULL", "router alert", "IPv6 explicit NULL", 69 "implicit NULL", "rsvd", 70 /*5*/ "rsvd", "rsvd", "rsvd", "rsvd", "rsvd", 71 /*10*/ "rsvd", "rsvd", "rsvd", "rsvd", "rsvd", 72 /*15*/ "rsvd", 73 }; 74 75 /* 76 * RFC3032: MPLS label stack encoding 77 */ 78 void 79 mpls_print(const u_char *bp, u_int length) 80 { 81 const u_char *p; 82 u_int32_t v; 83 84 p = bp; 85 printf("MPLS"); 86 TCHECK2(*p, sizeof(v)); 87 memcpy(&v, p, sizeof(v)); 88 v = (u_int32_t)ntohl(v); 89 printf(" ("); /*)*/ 90 printf("label 0x%x", MPLS_LABEL(v)); 91 if (vflag && 92 MPLS_LABEL(v) < sizeof(mpls_labelname) / sizeof(mpls_labelname[0])) 93 printf("(%s)", mpls_labelname[MPLS_LABEL(v)]); 94 if (MPLS_EXP(v)) 95 printf(" exp 0x%x", MPLS_EXP(v)); 96 if (MPLS_STACK(v)) 97 printf("[S]"); 98 printf(" TTL %u", MPLS_TTL(v)); 99 /*(*/ 100 printf(")"); 101 102 p += sizeof(v); 103 104 switch (MPLS_LABEL(v)) { 105 case 0: /* IPv4 explicit NULL label */ 106 ip_print(p, length - (p - bp)); 107 break; 108 #ifdef INET6 109 case 2: /* IPv6 explicit NULL label */ 110 ip6_print(p, length - (p - bp)); 111 break; 112 #endif 113 default: 114 /* 115 * Since there's no indication of protocol in MPLS label 116 * encoding, we can print nothing further. 117 */ 118 return; 119 } 120 121 trunc: 122 printf("[|MPLS]"); 123 } 124