From: itojun <itojun>
Date: Thu, 21 Jun 2001 17:56:02 +0000 (+0000)
Subject: MPLS label encapsulation decoding, per RFC3032.
X-Git-Tag: tcpdump-3.7.1~178
X-Git-Url: https://git.tcpdump.org/tcpdump/commitdiff_plain/544c52e1ef8ee0ba92c7d259c062bbd24a1084eb

MPLS label encapsulation decoding, per RFC3032.
TODO: multiple labels.  other media types.
---

diff --git a/Makefile.in b/Makefile.in
index af3bcced..524914e5 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -17,7 +17,7 @@
 #  WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 #  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 #
-# @(#) $Header: /tcpdump/master/tcpdump/Makefile.in,v 1.251 2001-06-12 05:17:16 guy Exp $ (LBL)
+# @(#) $Header: /tcpdump/master/tcpdump/Makefile.in,v 1.252 2001-06-21 17:56:02 itojun Exp $ (LBL)
 
 #
 # Various configurable paths (remember to edit Makefile.in, not Makefile)
@@ -75,7 +75,7 @@ CSRC =	addrtoname.c gmt2local.c machdep.c parsenfsfh.c \
 	print-igrp.c print-ip.c print-ipcomp.c print-ipx.c \
 	print-isakmp.c print-isoclns.c print-krb.c print-l2tp.c \
 	print-lane.c print-lcp.c print-llc.c print-lwres.c \
-	print-mobile.c print-nfs.c print-ntp.c print-null.c \
+	print-mobile.c print-mpls.c print-nfs.c print-ntp.c print-null.c \
 	print-ospf.c print-pim.c print-ppp.c print-pppoe.c \
 	print-pptp.c print-radius.c print-raw.c print-rip.c \
 	print-rx.c print-sctp.c print-sl.c print-sll.c print-smb.c \
diff --git a/ethertype.h b/ethertype.h
index ca6dbfc8..fcfd3ec4 100644
--- a/ethertype.h
+++ b/ethertype.h
@@ -18,7 +18,7 @@
  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- * @(#) $Header: /tcpdump/master/tcpdump/ethertype.h,v 1.15 2001-04-03 05:21:24 fenner Exp $ (LBL)
+ * @(#) $Header: /tcpdump/master/tcpdump/ethertype.h,v 1.16 2001-06-21 17:56:02 itojun Exp $ (LBL)
  */
 
 /*
@@ -105,6 +105,12 @@
 #ifndef ETHERTYPE_PPP
 #define	ETHERTYPE_PPP		0x880b
 #endif
+#ifndef	ETHERTYPE_MPLS
+#define	ETHERTYPE_MPLS		0x8847
+#endif
+#ifndef	ETHERTYPE_MPLS_MULTI
+#define	ETHERTYPE_MPLS_MULTI	0x8848
+#endif
 #ifndef ETHERTYPE_PPPOED
 #define ETHERTYPE_PPPOED	0x8863
 #endif
diff --git a/interface.h b/interface.h
index 21f2481f..3d5634e5 100644
--- a/interface.h
+++ b/interface.h
@@ -18,7 +18,7 @@
  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- * @(#) $Header: /tcpdump/master/tcpdump/interface.h,v 1.162 2001-06-20 07:40:44 guy Exp $ (LBL)
+ * @(#) $Header: /tcpdump/master/tcpdump/interface.h,v 1.163 2001-06-21 17:56:03 itojun Exp $ (LBL)
  */
 
 #ifndef tcpdump_interface_h
@@ -279,6 +279,7 @@ extern void radius_print(const u_char *, u_int);
 extern void lwres_print(const u_char *, u_int);
 extern void pptp_print(const u_char *, u_int);
 extern void sctp_print(const u_char *, const u_char *, u_int);
+extern void mpls_print(const u_char *, u_int);
 
 #ifdef INET6
 extern void ip6_print(const u_char *, int);
diff --git a/print-ether.c b/print-ether.c
index 24d19929..30956ed7 100644
--- a/print-ether.c
+++ b/print-ether.c
@@ -20,7 +20,7 @@
  */
 #ifndef lint
 static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/tcpdump/print-ether.c,v 1.63 2001-03-12 00:24:54 guy Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/tcpdump/print-ether.c,v 1.64 2001-06-21 17:56:03 itojun Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -234,6 +234,11 @@ ether_encap_print(u_short ethertype, const u_char *p,
 		}
 		return (1);
 
+	case ETHERTYPE_MPLS:
+	case ETHERTYPE_MPLS_MULTI:
+		mpls_print(p, length);
+		return (1);
+
 	case ETHERTYPE_LAT:
 	case ETHERTYPE_SCA:
 	case ETHERTYPE_MOPRC:
diff --git a/print-mpls.c b/print-mpls.c
new file mode 100644
index 00000000..69afa17f
--- /dev/null
+++ b/print-mpls.c
@@ -0,0 +1,121 @@
+/*
+ * 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 1.1 2001-06-21 17:56:04 itojun Exp $ (LBL)";
+#endif
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <sys/param.h>
+#include <sys/time.h>
+#include <sys/socket.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]");
+}