support printing cdp over gre and ppp

ok deraadt@ mpi@ sthen@

5 files changed, 16 insertions, 14 deletions

diff --git a/usr.sbin/tcpdump/interface.h b/usr.sbin/tcpdump/interface.h
index 83bd145e8e2..70fe8e2bf33 100644
--- a/usr.sbin/tcpdump/interface.h
+++ b/usr.sbin/tcpdump/interface.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: interface.h,v 1.79 2018/10/22 16:12:45 kn Exp $	*/
+/*	$OpenBSD: interface.h,v 1.80 2019/04/05 00:57:59 dlg Exp $	*/
 
 /*
  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
@@ -20,7 +20,7 @@
  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- * @(#) $Id: interface.h,v 1.79 2018/10/22 16:12:45 kn Exp $ (LBL)
+ * @(#) $Id: interface.h,v 1.80 2019/04/05 00:57:59 dlg Exp $ (LBL)
  */
 
 #ifndef tcpdump_interface_h
@@ -270,8 +270,7 @@ extern void ike_print(const u_char *, u_int);
 extern void udpencap_print(const u_char *, u_int, const u_char *);
 extern void ah_print(const u_char *, u_int, const u_char *);
 extern void esp_print(const u_char *, u_int, const u_char *);
-extern void cdp_print(const u_char *, u_int, u_int, const u_char *,
-	const u_char *);
+extern void cdp_print(const u_char *, u_int, u_int, int);
 extern void stp_print(const u_char *, u_int);
 extern void radius_print(const u_char *, u_int);
 extern void lwres_print(const u_char *, u_int);
diff --git a/usr.sbin/tcpdump/print-cdp.c b/usr.sbin/tcpdump/print-cdp.c
index 4a2586e50e7..61a9ac96e5a 100644
--- a/usr.sbin/tcpdump/print-cdp.c
+++ b/usr.sbin/tcpdump/print-cdp.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: print-cdp.c,v 1.6 2016/03/29 04:07:50 canacar Exp $	*/
+/*	$OpenBSD: print-cdp.c,v 1.7 2019/04/05 00:57:59 dlg Exp $	*/
 
 /*
  * Copyright (c) 1992, 1993, 1994, 1995, 1996, 1997
@@ -46,20 +46,17 @@ void cdp_print_prefixes(const u_char * p, int l);
  * Returns non-zero IFF it succeeds in printing the header
  */
 void
-cdp_print(const u_char *p, u_int length, u_int caplen,
-	  const u_char *esrc, const u_char *edst)
+cdp_print(const u_char *p, u_int length, u_int caplen, int i)
 {
-	int i;
 	int type, len;
 
 	/* Cisco Discovery Protocol */
 
-	if (caplen < 12) {
+	if (caplen < i + 4) {
 		printf("[|cdp]");
 		return;
 	}
 
-	i=8;		/* CDP data starts at offset 8 */
 	printf("CDP v%d, ttl=%ds", p[i], p[i+1]);
 	i+=4;		/* skip version, TTL and chksum */
 
diff --git a/usr.sbin/tcpdump/print-gre.c b/usr.sbin/tcpdump/print-gre.c
index c4e3be0d49f..a1ed13d3392 100644
--- a/usr.sbin/tcpdump/print-gre.c
+++ b/usr.sbin/tcpdump/print-gre.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: print-gre.c,v 1.23 2019/04/02 11:10:54 dlg Exp $	*/
+/*	$OpenBSD: print-gre.c,v 1.24 2019/04/05 00:57:59 dlg Exp $	*/
 
 /*
  * Copyright (c) 2002 Jason L. Wright (jason@thought.net)
@@ -269,6 +269,9 @@ gre_print_0(const u_char *p, u_int length)
 	case ERSPAN_II:
 		gre_print_erspan2(p, length);
 		break;
+	case 0x2000:
+		cdp_print(p, length, l, 0);
+		break;
 	default:
 		printf("unknown-proto-%04x", proto);
 	}
diff --git a/usr.sbin/tcpdump/print-llc.c b/usr.sbin/tcpdump/print-llc.c
index f613f582f51..a18e859930e 100644
--- a/usr.sbin/tcpdump/print-llc.c
+++ b/usr.sbin/tcpdump/print-llc.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: print-llc.c,v 1.20 2015/11/16 00:16:39 mmcc Exp $	*/
+/*	$OpenBSD: print-llc.c,v 1.21 2019/04/05 00:57:59 dlg Exp $	*/
 
 /*
  * Copyright (c) 1992, 1993, 1994, 1995, 1996, 1997
@@ -100,7 +100,7 @@ llc_print(const u_char *p, u_int length, u_int caplen,
 
 		/* Cisco Discovery Protocol  - SNAP & ether type 0x2000 */
 		if (llc.ethertype[0] == 0x20 && llc.ethertype[1] == 0x00) {
-			cdp_print(p, length, caplen, esrc, edst);
+			cdp_print(p, length, caplen, 8);
 			return (1);
 		}
 		/* Shared Spanning Tree Protocol - SNAP & ether type 0x010b */
diff --git a/usr.sbin/tcpdump/print-ppp.c b/usr.sbin/tcpdump/print-ppp.c
index ec13ff496eb..78edc46a073 100644
--- a/usr.sbin/tcpdump/print-ppp.c
+++ b/usr.sbin/tcpdump/print-ppp.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: print-ppp.c,v 1.32 2018/02/06 03:41:58 dlg Exp $	*/
+/*	$OpenBSD: print-ppp.c,v 1.33 2019/04/05 00:57:59 dlg Exp $	*/
 
 /*
  * Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996, 1997
@@ -390,6 +390,9 @@ ppp_print(const u_char *p, u_int length)
 	case PPP_IPV6CP:
 		handle_ipv6cp(p, l);
 		break;
+	case PPP_CDP:
+		cdp_print(p, length, l, 0);
+		break;
 	}
 }