tcpdump/print-mpls.c

124 lines
3.6 KiB
C

/*
* 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[] =
"@(#) $Header: /tcpdump/master/tcpdump/print-mpls.c,v 1.2 2001-06-26 06:24:57 guy Exp $ (LBL)";
#endif
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <sys/param.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "addrtoname.h"
#include "interface.h"
#include "extract.h" /* must come after interface.h */
#define LABEL_MASK 0xfffff000
#define LABEL_SHIFT 12
#define EXP_MASK 0x00000e00
#define EXP_SHIFT 9
#define STACK_MASK 0x00000100
#define STACK_SHIFT 8
#define TTL_MASK 0x000000ff
#define TTL_SHIFT 0
#define MPLS_LABEL(x) (((x) & LABEL_MASK) >> LABEL_SHIFT)
#define MPLS_EXP(x) (((x) & EXP_MASK) >> EXP_SHIFT)
#define MPLS_STACK(x) (((x) & STACK_MASK) >> STACK_SHIFT)
#define MPLS_TTL(x) (((x) & TTL_MASK) >> TTL_SHIFT)
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 v;
p = bp;
printf("MPLS");
TCHECK2(*p, sizeof(v));
memcpy(&v, p, sizeof(v));
v = (u_int32_t)ntohl(v);
printf(" ("); /*)*/
printf("label 0x%x", MPLS_LABEL(v));
if (vflag &&
MPLS_LABEL(v) < sizeof(mpls_labelname) / sizeof(mpls_labelname[0]))
printf("(%s)", mpls_labelname[MPLS_LABEL(v)]);
if (MPLS_EXP(v))
printf(" exp 0x%x", MPLS_EXP(v));
if (MPLS_STACK(v))
printf("[S]");
printf(" TTL %u", MPLS_TTL(v));
/*(*/
printf(")");
p += sizeof(v);
switch (MPLS_LABEL(v)) {
case 0: /* IPv4 explicit NULL label */
ip_print(p, length - (p - bp));
break;
#ifdef INET6
case 2: /* IPv6 explicit NULL label */
ip6_print(p, length - (p - bp));
break;
#endif
default:
/*
* Since there's no indication of protocol in MPLS label
* encoding, we can print nothing further.
*/
return;
}
trunc:
printf("[|MPLS]");
}