handle the 802.1Q i-tag format for provider backbone bridges.

1 files changed, 46 insertions, 1 deletions

diff --git a/usr.sbin/tcpdump/print-ether.c b/usr.sbin/tcpdump/print-ether.c
index a3163a8057b..0625f34c204 100644
--- a/usr.sbin/tcpdump/print-ether.c
+++ b/usr.sbin/tcpdump/print-ether.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: print-ether.c,v 1.33 2018/10/22 16:12:45 kn Exp $	*/
+/*	$OpenBSD: print-ether.c,v 1.34 2018/11/18 08:53:37 dlg Exp $	*/
 
 /*
  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
@@ -50,6 +50,7 @@ const u_char *packetp;
 const u_char *snapend;
 
 void ether_macctl(const u_char *, u_int);
+void ether_pbb_print(const u_char *, u_int, u_int);
 
 void
 ether_print(const u_char *bp, u_int length)
@@ -166,6 +167,43 @@ ether_tryprint(const u_char *p, u_int length, int first_header)
 		putchar('\n');
 }
 
+void
+ether_pbb_print(const u_char *bp, u_int length, u_int caplen)
+{
+	uint32_t itag;
+	uint8_t pri, res;
+
+	if (caplen < sizeof(itag))
+		goto trunc;
+
+	itag = EXTRACT_32BITS(bp);
+
+	bp += sizeof(itag);
+	length -= sizeof(itag);
+	caplen -= sizeof(itag);
+
+	pri = itag >> 29;
+	if (pri <= 1)
+		pri = !pri;
+
+	res = (itag >> 24) & 0x7;
+
+	printf("802.1Q ivid %u pri %u ", itag & 0xffffff, pri);
+	if (itag & (1 << 28))
+		printf("dei ");
+	if (itag & (1 << 27))
+		printf("uca ");
+	if (res)
+		printf("res %u! ", res);
+
+	ether_tryprint(bp, length, 0);
+
+	return;
+
+trunc:
+	printf("[|pbb] ");
+}
+
 /*
  * Prints the packet encapsulated in an Ethernet data segment
  * (or an equivalent encapsulation), given the Ethernet type code.
@@ -251,6 +289,13 @@ recurse:
 		}
 		return (1);
 
+#ifndef ETHERTYPE_PBB
+#define ETHERTYPE_PBB 0x88e7
+#endif
+	case ETHERTYPE_PBB:
+		ether_pbb_print(p, length, caplen);
+		return (1);
+
 #ifdef PPP
 	case ETHERTYPE_PPPOEDISC:
 	case ETHERTYPE_PPPOE: