4 files changed, 738 insertions, 3 deletions

diff --git a/usr.sbin/tcpdump/Makefile b/usr.sbin/tcpdump/Makefile
index 93a52797540..6de664c0a8b 100644
--- a/usr.sbin/tcpdump/Makefile
+++ b/usr.sbin/tcpdump/Makefile
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile,v 1.18 2000/01/16 11:20:14 jakob Exp $
+#	$OpenBSD: Makefile,v 1.19 2000/01/16 11:43:57 jakob Exp $
 #
 #  Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994
 # 	The Regents of the University of California.  All rights reserved.
@@ -42,6 +42,7 @@ SRCS=	tcpdump.c addrtoname.c \
 	util.c bpf_dump.c parsenfsfh.c version.c machdep.c print-igrp.c \
 	print-gre.c print-radius.c print-enc.c print-cnfp.c \
 	print-ipsec.c print-ike.c print-raw.c print-l2tp.c print-mobile.c \
+	print-bgp.c \
 	gmt2local.c savestr.c setsignal.c
 
 AWKS =	atime.awk packetdat.awk send-ack.awk stime.awk
diff --git a/usr.sbin/tcpdump/interface.h b/usr.sbin/tcpdump/interface.h
index b188707786b..03c5ba962b9 100644
--- a/usr.sbin/tcpdump/interface.h
+++ b/usr.sbin/tcpdump/interface.h
@@ -18,7 +18,7 @@
  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- * @(#) $Header: /cvs/OpenBSD/src/usr.sbin/tcpdump/interface.h,v 1.14 2000/01/16 11:20:14 jakob Exp $ (LBL)
+ * @(#) $Header: /cvs/OpenBSD/src/usr.sbin/tcpdump/interface.h,v 1.15 2000/01/16 11:43:57 jakob Exp $ (LBL)
  */
 
 #ifndef tcpdump_interface_h
@@ -172,6 +172,7 @@ extern void atalk_print(const u_char *, u_int);
 extern void atalk_print_llap(const u_char *, u_int);
 extern void atm_if_print(u_char *, const struct pcap_pkthdr *, const u_char *);
 extern void bootp_print(const u_char *, u_int, u_short, u_short);
+extern void bgp_print(const u_char *, int);
 extern void decnet_print(const u_char *, u_int, u_int);
 extern void default_print(const u_char *, u_int);
 extern void default_print_unaligned(const u_char *, u_int);
diff --git a/usr.sbin/tcpdump/print-bgp.c b/usr.sbin/tcpdump/print-bgp.c
new file mode 100644
index 00000000000..7be61b285b8
--- /dev/null
+++ b/usr.sbin/tcpdump/print-bgp.c
@@ -0,0 +1,720 @@
+/*	$OpenBSD: print-bgp.c,v 1.1 2000/01/16 11:43:57 jakob Exp $	*/
+
+/*
+ * Copyright (C) 1999 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.
+ */
+
+#include <sys/param.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+
+#include <netinet/in.h>
+#include <netinet/in_systm.h>
+#include <netinet/ip.h>
+#include <netinet/ip_var.h>
+#include <netinet/udp.h>
+#include <netinet/udp_var.h>
+
+#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "interface.h"
+#include "addrtoname.h"
+
+struct bgp {
+	u_int8_t bgp_marker[16];
+	u_int16_t bgp_len;
+	u_int8_t bgp_type;
+};
+#define BGP_SIZE		19	/* unaligned */
+
+#define BGP_OPEN		1
+#define BGP_UPDATE		2
+#define BGP_NOTIFICATION	3
+#define BGP_KEEPALIVE		4
+
+struct bgp_open {
+	u_int8_t bgpo_marker[16];
+	u_int16_t bgpo_len;
+	u_int8_t bgpo_type;
+	u_int8_t bgpo_version;
+	u_int16_t bgpo_myas;
+	u_int16_t bgpo_holdtime;
+	u_int32_t bgpo_id;
+	u_int8_t bgpo_optlen;
+	/* options should follow */
+};
+
+struct bgp_opt {
+	u_int8_t bgpopt_type;
+	u_int8_t bgpopt_len;
+	/* variable length */
+};
+
+struct bgp_notification {
+	u_int8_t bgpn_marker[16];
+	u_int16_t bgpn_len;
+	u_int8_t bgpn_type;
+	u_int8_t bgpn_major;
+	u_int8_t bgpn_minor;
+	/* data should follow */
+};
+
+struct bgp_attr {
+	u_int8_t bgpa_flags;
+	u_int8_t bgpa_type;
+	union {
+		u_int8_t len;
+		u_int16_t elen;
+	} bgpa_len;
+#define bgp_attr_len(p) \
+	(((p)->bgpa_flags & 0x10) ? \
+		ntohs((p)->bgpa_len.elen) : (p)->bgpa_len.len)
+#define bgp_attr_off(p) \
+	(((p)->bgpa_flags & 0x10) ? 4 : 3)
+};
+
+#define BGPTYPE_ORIGIN			1
+#define BGPTYPE_AS_PATH			2
+#define BGPTYPE_NEXT_HOP		3
+#define BGPTYPE_MULTI_EXIT_DISC		4
+#define BGPTYPE_LOCAL_PREF		5
+#define BGPTYPE_ATOMIC_AGGREGATE	6
+#define BGPTYPE_AGGREGATOR		7
+#define	BGPTYPE_COMMUNITIES		8	/* RFC1997 */
+#define	BGPTYPE_ORIGINATOR_ID		9	/* RFC1998 */
+#define	BGPTYPE_CLUSTER_LIST		10	/* RFC1998 */
+#define	BGPTYPE_DPA			11	/* work in progress */
+#define	BGPTYPE_ADVERTISERS		12	/* RFC1863 */
+#define	BGPTYPE_RCID_PATH		13	/* RFC1863 */
+#define BGPTYPE_MP_REACH_NLRI		14	/* RFC2283 */
+#define BGPTYPE_MP_UNREACH_NLRI		15	/* RFC2283 */
+
+
+static const char *bgptype[] = {
+	NULL, "OPEN", "UPDATE", "NOTIFICATION", "KEEPALIVE",
+};
+#define bgp_type(x) num_or_str(bgptype, sizeof(bgptype)/sizeof(bgptype[0]), (x))
+
+static const char *bgpopt_type[] = {
+	NULL, "Authentication Information",
+};
+#define bgp_opttype(x) \
+	num_or_str(bgpopt_type, sizeof(bgpopt_type)/sizeof(bgpopt_type[0]), (x))
+
+static const char *bgpnotify_major[] = {
+	NULL, "Message Header Error",
+	"OPEN Message Error", "UPDATE Message Error",
+	"Hold Timer Expired", "Finite State Machine Error",
+	"Cease",
+};
+#define bgp_notify_major(x) \
+	num_or_str(bgpnotify_major, \
+		sizeof(bgpnotify_major)/sizeof(bgpnotify_major[0]), (x))
+
+static const char *bgpnotify_minor_1[] = {
+	NULL, "Connection Not Synchronized",
+	"Bad Message Length", "Bad Message Type",
+};
+
+static const char *bgpnotify_minor_2[] = {
+	NULL, "Unsupported Version Number",
+	"Bad Peer AS", "Bad BGP Identifier",
+	"Unsupported Optional Parameter", "Authentication Failure",
+	"Unacceptable Hold Time",
+};
+
+static const char *bgpnotify_minor_3[] = {
+	NULL, "Malformed Attribute List",
+	"Unrecognized Well-known Attribute", "Missing Well-known Attribute",
+	"Attribute Flags Error", "Attribute Length Error",
+	"Invalid ORIGIN Attribute", "AS Routing Loop",
+	"Invalid NEXT_HOP Attribute", "Optional Attribute Error",
+	"Invalid Network Field", "Malformed AS_PATH",
+};
+
+static const char **bgpnotify_minor[] = {
+	NULL, bgpnotify_minor_1, bgpnotify_minor_2, bgpnotify_minor_3,
+};
+static const int bgpnotify_minor_siz[] = {
+	0, sizeof(bgpnotify_minor_1)/sizeof(bgpnotify_minor_1[0]),
+	sizeof(bgpnotify_minor_2)/sizeof(bgpnotify_minor_2[0]),
+	sizeof(bgpnotify_minor_3)/sizeof(bgpnotify_minor_3[0]),
+};
+
+static const char *bgpattr_origin[] = {
+	"IGP", "EGP", "INCOMPLETE",
+};
+#define bgp_attr_origin(x) \
+	num_or_str(bgpattr_origin, \
+		sizeof(bgpattr_origin)/sizeof(bgpattr_origin[0]), (x))
+
+static const char *bgpattr_type[] = {
+	NULL, "ORIGIN", "AS_PATH", "NEXT_HOP",
+	"MULTI_EXIT_DISC", "LOCAL_PREF", "ATOMIC_AGGREGATE", "AGGREGATOR",
+	"COMMUNITIES", "ORIGINATOR_ID", "CLUSTER_LIST", "DPA",
+	"ADVERTISERS", "RCID_PATH", "MP_REACH_NLRI", "MP_UNREACH_NLRI",
+};
+#define bgp_attr_type(x) \
+	num_or_str(bgpattr_type, \
+		sizeof(bgpattr_type)/sizeof(bgpattr_type[0]), (x))
+
+/* Subsequent address family identifier, RFC2283 section 7 */
+static const char *bgpattr_nlri_safi[] = {
+    "Reserved", "Unicast", "Multicast", "Unicast+Multicast",
+};
+#define bgp_attr_nlri_safi(x) \
+	num_or_str(bgpattr_nlri_safi, \
+		sizeof(bgpattr_nlri_safi)/sizeof(bgpattr_nlri_safi[0]), (x))
+
+/* well-known community */
+#define BGP_COMMUNITY_NO_EXPORT			0xffffff01
+#define BGP_COMMUNITY_NO_ADVERT			0xffffff02
+#define BGP_COMMUNITY_NO_EXPORT_SUBCONFED	0xffffff03
+
+/* RFC1700 address family numbers */
+#define AFNUM_INET	1
+#define AFNUM_INET6	2
+#define AFNUM_NSAP	3
+#define AFNUM_HDLC	4
+#define AFNUM_BBN1822	5
+#define AFNUM_802	6
+#define AFNUM_E163	7
+#define AFNUM_E164	8
+#define AFNUM_F69	9
+#define AFNUM_X121	10
+#define AFNUM_IPX	11
+#define AFNUM_ATALK	12
+#define AFNUM_DECNET	13
+#define AFNUM_BANYAN	14
+#define AFNUM_E164NSAP	15
+
+static const char *afnumber[] = {
+	"Reserved", "IPv4", "IPv6", "NSAP", "HDLC",
+	"BBN 1822", "802", "E.163", "E.164", "F.69",
+	"X.121", "IPX", "Appletalk", "Decnet IV", "Banyan Vines",
+	"E.164 with NSAP subaddress",
+};
+#define af_name(x) \
+	(((x) == 65535) ? afnumber[0] : \
+		num_or_str(afnumber, \
+			sizeof(afnumber)/sizeof(afnumber[0]), (x)))
+
+
+static const char *
+num_or_str(const char **table, size_t siz, int value)
+{
+	static char buf[20];
+	if (value < 0 || siz <= value || table[value] == NULL) {
+		snprintf(buf, sizeof(buf), "#%d", value);
+		return buf;
+	} else
+		return table[value];
+}
+
+static const char *
+bgp_notify_minor(int major, int minor)
+{
+	static const char **table;
+	int siz;
+	static char buf[20];
+	const char *p;
+
+	if (0 <= major
+	 && major < sizeof(bgpnotify_minor)/sizeof(bgpnotify_minor[0])
+	 && bgpnotify_minor[major]) {
+		table = bgpnotify_minor[major];
+		siz = bgpnotify_minor_siz[major];
+		if (0 <= minor && minor < siz && table[minor])
+			p = table[minor];
+		else
+			p = NULL;
+	} else
+		p = NULL;
+	if (p == NULL) {
+		snprintf(buf, sizeof(buf), "#%d", minor);
+		return buf;
+	} else
+		return p;
+}
+
+static int
+decode_prefix4(const u_char *pd, char *buf, int buflen)
+{
+	struct in_addr addr;
+	int plen;
+
+	plen = pd[0];
+	if (plen < 0 || 32 < plen)
+		return -1;
+
+	memset(&addr, 0, sizeof(addr));
+	memcpy(&addr, &pd[1], (plen + 7) / 8);
+	if (plen % 8) {
+		((u_char *)&addr)[(plen + 7) / 8 - 1] &=
+			((0xff00 >> (plen % 8)) & 0xff);
+	}
+	snprintf(buf, buflen, "%s/%d", getname((char *)&addr), plen);
+	return 1 + (plen + 7) / 8;
+}
+
+#ifdef INET6
+static int
+decode_prefix6(const u_char *pd, char *buf, int buflen)
+{
+	struct in6_addr addr;
+	int plen;
+
+	plen = pd[0];
+	if (plen < 0 || 128 < plen)
+		return -1;
+
+	memset(&addr, 0, sizeof(addr));
+	memcpy(&addr, &pd[1], (plen + 7) / 8);
+	if (plen % 8) {
+		addr.s6_addr[(plen + 7) / 8 - 1] &=
+			((0xff00 >> (plen % 8)) & 0xff);
+	}
+	snprintf(buf, buflen, "%s/%d", getname6((char *)&addr), plen);
+	return 1 + (plen + 7) / 8;
+}
+#endif
+
+static void
+bgp_attr_print(const struct bgp_attr *attr, const u_char *dat, int len)
+{
+	int i;
+	u_int16_t af;
+	u_int8_t safi, snpa;
+	int advance;
+	int tlen;
+	const u_char *p;
+	char buf[256];
+
+	p = dat;
+
+	switch (attr->bgpa_type) {
+	case BGPTYPE_ORIGIN:
+		if (len != 1)
+			printf(" invalid len");
+		else
+			printf(" %s", bgp_attr_origin(p[0]));
+		break;
+	case BGPTYPE_AS_PATH:
+		if (len % 2) {
+			printf(" invalid len");
+			break;
+		}
+		while (p < dat + len) {
+			/*
+			 * under RFC1965, p[0] means:
+			 * 1: AS_SET 2: AS_SEQUENCE
+			 * 3: AS_CONFED_SET 4: AS_CONFED_SEQUENCE
+			 */
+			printf(" ");
+			if (p[0] == 3 || p[0] == 4)
+				printf("confed");
+			printf("%s", (p[0] & 1) ? "{" : "");
+			for (i = 0; i < p[1]; i += 2) {
+				printf("%s%u", i == 0 ? "" : " ",
+					ntohs(*(u_int16_t *)&p[2 + i]));
+			}
+			printf("%s", (p[0] & 1) ? "}" : "");
+			p += 2 + p[1] * 2;
+		}
+		break;
+	case BGPTYPE_NEXT_HOP:
+		if (len != 4)
+			printf(" invalid len");
+		else
+			printf(" %s", getname(p));
+		break;
+	case BGPTYPE_MULTI_EXIT_DISC:
+	case BGPTYPE_LOCAL_PREF:
+		if (len != 4)
+			printf(" invalid len");
+		else
+			printf(" %u", (u_int32_t)ntohl(*(u_int32_t *)p));
+		break;
+	case BGPTYPE_ATOMIC_AGGREGATE:
+		if (len != 0)
+			printf(" invalid len");
+		break;
+	case BGPTYPE_AGGREGATOR:
+		if (len != 6) {
+			printf(" invalid len");
+			break;
+		}
+		printf(" AS #%u, origin %s", ntohs(*(u_int16_t *)p),
+			getname(p + 2));
+		break;
+	case BGPTYPE_COMMUNITIES:
+		if (len % 4) {
+			printf(" invalid len");
+			break;
+		}
+		for (i = 0; i < len; i++) {
+			u_int32_t comm;
+			comm = (u_int32_t)ntohl(*(u_int32_t *)&p[i]);
+			switch (comm) {
+			case BGP_COMMUNITY_NO_EXPORT:
+				printf(" NO_EXPORT");
+				break;
+			case BGP_COMMUNITY_NO_ADVERT:
+				printf(" NO_ADVERTISE");
+				break;
+			case BGP_COMMUNITY_NO_EXPORT_SUBCONFED:
+				printf(" NO_EXPORT_SUBCONFED");
+				break;
+			default:
+				printf(" (AS #%d value 0x%04x)",
+					(comm >> 16) & 0xffff, comm & 0xfffff);
+				break;
+			}
+		}
+		break;
+	case BGPTYPE_MP_REACH_NLRI:
+		af = ntohs(*(u_int16_t *)p);
+		safi = p[2];
+		if (safi >= 128)
+			printf(" %s vendor specific,", af_name(af));
+		else {
+			printf(" %s %s,", af_name(af),
+				bgp_attr_nlri_safi(safi));
+		}
+		p += 3;
+
+		if (af == AFNUM_INET)
+			;
+#ifdef INET6
+		else if (af == AFNUM_INET6)
+			;
+#endif
+		else
+			break;
+
+		tlen = p[0];
+		if (tlen) {
+			printf(" nexthop");
+			if (af == AFNUM_INET)
+				advance = 4;
+#ifdef INET6
+			else if (af == AFNUM_INET6)
+				advance = 16;
+#endif
+
+			for (i = 0; i < tlen; i += advance) {
+				if (af == AFNUM_INET)
+					printf(" %s", getname(p + 1 + i));
+#ifdef INET6
+				else if (af == AFNUM_INET6)
+					printf(" %s", getname6(p + 1 + i));
+#endif
+			}
+			printf(",");
+		}
+		p += 1 + tlen;
+
+		snpa = p[0];
+		p++;
+		if (snpa) {
+			printf(" %u snpa", snpa);
+			for (/*nothing*/; snpa > 0; snpa--) {
+				printf("(%d bytes)", p[0]);
+				p += p[0] + 1;
+			}
+			printf(",");
+		}
+
+		printf(" NLRI");
+		while (len - (p - dat) > 0) {
+			if (af == AFNUM_INET)
+				advance = decode_prefix4(p, buf, sizeof(buf));
+#ifdef INET6
+			else if (af == AFNUM_INET6)
+				advance = decode_prefix6(p, buf, sizeof(buf));
+#endif
+			printf(" %s", buf);
+
+			p += advance;
+		}
+
+		break;
+
+	case BGPTYPE_MP_UNREACH_NLRI:
+		af = ntohs(*(u_int16_t *)p);
+		safi = p[2];
+		if (safi >= 128)
+			printf(" %s vendor specific,", af_name(af));
+		else {
+			printf(" %s %s,", af_name(af),
+				bgp_attr_nlri_safi(safi));
+		}
+		p += 3;
+
+		printf(" Withdraw");
+		while (len - (p - dat) > 0) {
+			if (af == AFNUM_INET)
+				advance = decode_prefix4(p, buf, sizeof(buf));
+#ifdef INET6
+			else if (af == AFNUM_INET6)
+				advance = decode_prefix6(p, buf, sizeof(buf));
+#endif
+			printf(" %s", buf);
+
+			p += advance;
+		}
+		break;
+	default:
+		break;
+	}
+}
+
+static void
+bgp_open_print(const u_char *dat, int length)
+{
+	struct bgp_open bgpo;
+	struct bgp_opt bgpopt;
+	int hlen;
+	const u_char *opt;
+	int i;
+
+	memcpy(&bgpo, dat, sizeof(bgpo));
+	hlen = ntohs(bgpo.bgpo_len);
+
+	printf(": Version %d,", bgpo.bgpo_version);
+	printf(" AS #%u,", ntohs(bgpo.bgpo_myas));
+	printf(" Holdtime %u,", ntohs(bgpo.bgpo_holdtime));
+	printf(" ID %s,", getname((char *)&bgpo.bgpo_id));
+	printf(" Option length %u", bgpo.bgpo_optlen);
+
+	/* ugly! */
+	opt = &((struct bgp_open *)dat)->bgpo_optlen;
+	opt++;
+
+	for (i = 0; i < bgpo.bgpo_optlen; i++) {
+		memcpy(&bgpopt, &opt[i], sizeof(bgpopt));
+		if (i + 2 + bgpopt.bgpopt_len > bgpo.bgpo_optlen) {
+			printf(" [|opt %d %d]", bgpopt.bgpopt_len, bgpopt.bgpopt_type);
+			break;
+		}
+
+		printf(" (option %s, len=%d)", bgp_opttype(bgpopt.bgpopt_type),
+			bgpopt.bgpopt_len);
+		i += sizeof(bgpopt) + bgpopt.bgpopt_len;
+	}
+}
+
+static void
+bgp_update_print(const u_char *dat, int length)
+{
+	struct bgp bgp;
+	struct bgp_attr bgpa;
+	int hlen;
+	const u_char *p;
+	int len;
+	int i;
+	int newline;
+
+	memcpy(&bgp, dat, sizeof(bgp));
+	hlen = ntohs(bgp.bgp_len);
+	p = dat + BGP_SIZE;	/*XXX*/
+	printf(":");
+
+	/* Unfeasible routes */
+	len = ntohs(*(u_int16_t *)p);
+	if (len) {
+		printf(" (Withdrawn routes: %d bytes)", len);
+	}
+	p += 2 + len;
+
+	len = ntohs(*(u_int16_t *)p);
+	if (len) {
+		/* do something more useful!*/
+		i = 2;
+		printf(" (Path attributes:");	/* ) */
+		newline = 0;
+		while (i < 2 + len) {
+			int alen, aoff;
+
+			memcpy(&bgpa, &p[i], sizeof(bgpa));
+			alen = bgp_attr_len(&bgpa);
+			aoff = bgp_attr_off(&bgpa);
+
+			if (vflag && newline)
+				printf("\n\t\t");
+			else
+				printf(" ");
+			printf("(");		/* ) */
+			printf("%s", bgp_attr_type(bgpa.bgpa_type));
+			if (bgpa.bgpa_flags) {
+				printf("[%s%s%s%s]",
+					bgpa.bgpa_flags & 0x80 ? "O" : "",
+					bgpa.bgpa_flags & 0x40 ? "T" : "",
+					bgpa.bgpa_flags & 0x20 ? "P" : "",
+					bgpa.bgpa_flags & 0x00 ? "E" : "");
+			}
+
+			bgp_attr_print(&bgpa, &p[i + aoff], alen);
+			newline = 1;
+
+			/* ( */
+			printf(")");	
+
+			i += aoff + alen;
+		}
+
+		/* ( */
+		printf(")");
+	}
+	p += 2 + len;
+
+	if (len && dat + length > p)
+		printf("\n\t\t");
+	if (dat + length > p) {
+		printf("(NLRI:");	/* ) */
+		while (dat + length > p) {
+			char buf[256];
+			i = decode_prefix4(p, buf, sizeof(buf));
+			printf(" %s", buf);
+			if (i < 0)
+				break;
+			p += i;
+		}
+
+		/* ( */
+		printf(")");
+	}
+}
+
+static void
+bgp_notification_print(const u_char *dat, int length)
+{
+	struct bgp_notification bgpn;
+	int hlen;
+
+	memcpy(&bgpn, dat, sizeof(bgpn));
+	hlen = ntohs(bgpn.bgpn_len);
+
+	printf(": error %s,", bgp_notify_major(bgpn.bgpn_major));
+	printf(" subcode %s",
+		bgp_notify_minor(bgpn.bgpn_major, bgpn.bgpn_minor));
+}
+
+static void
+bgp_header_print(const u_char *dat, int length)
+{
+	struct bgp bgp;
+
+	memcpy(&bgp, dat, sizeof(bgp));
+	printf("(%s", bgp_type(bgp.bgp_type));		/* ) */
+
+	switch (bgp.bgp_type) {
+	case BGP_OPEN:
+		bgp_open_print(dat, length);
+		break;
+	case BGP_UPDATE:
+		bgp_update_print(dat, length);
+		break;
+	case BGP_NOTIFICATION:
+		bgp_notification_print(dat, length);
+		break;
+	}
+
+	/* ( */
+	printf(")");
+}
+
+void
+bgp_print(const u_char *dat, int length)
+{
+	const u_char *p;
+	const u_char *ep;
+	const u_char *start;
+	const u_char marker[] = {
+		0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
+		0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 
+	};
+	struct bgp bgp;
+	u_int16_t hlen;
+	int newline;
+
+	ep = dat + length;
+	if (snapend < dat + length)
+		ep = snapend;
+
+	printf(": BGP");
+
+	p = dat;
+	newline = 0;
+	start = p;
+	while (p < snapend) {
+		if (!TTEST2(p[0], 1))
+			break;
+		if (p[0] != 0xff) {
+			p++;
+			continue;
+		}
+
+		if (!TTEST2(p[0], sizeof(marker)))
+			break;
+		if (memcmp(p, marker, sizeof(marker)) != 0) {
+			p++;
+			continue;
+		}
+
+		/* found BGP header */
+		TCHECK2(p[0], BGP_SIZE);	/*XXX*/
+		memcpy(&bgp, p, sizeof(bgp));
+
+		if (start != p)
+			printf(" [|BGP]");
+
+		hlen = ntohs(bgp.bgp_len);
+		if (vflag && newline)
+			printf("\n\t");
+		else
+			printf(" ");
+		if (TTEST2(p[0], hlen)) {
+			bgp_header_print(p, hlen);
+			newline = 1;
+			p += hlen;
+			start = p;
+		} else {
+			printf("[|BGP %s]", bgp_type(bgp.bgp_type));
+			break;
+		}
+	}
+
+	return;
+
+trunc:
+	printf(" [|BGP]");
+}
diff --git a/usr.sbin/tcpdump/print-tcp.c b/usr.sbin/tcpdump/print-tcp.c
index 0d5aa025f04..c0646b9dee3 100644
--- a/usr.sbin/tcpdump/print-tcp.c
+++ b/usr.sbin/tcpdump/print-tcp.c
@@ -21,7 +21,7 @@
 
 #ifndef lint
 static const char rcsid[] =
-    "@(#) $Header: /cvs/OpenBSD/src/usr.sbin/tcpdump/print-tcp.c,v 1.9 1999/11/26 18:16:55 provos Exp $ (LBL)";
+    "@(#) $Header: /cvs/OpenBSD/src/usr.sbin/tcpdump/print-tcp.c,v 1.10 2000/01/16 11:43:58 jakob Exp $ (LBL)";
 #endif
 
 #include <sys/param.h>
@@ -381,6 +381,19 @@ tcp_print(register const u_char *bp, register u_int length,
 		}
 		putchar('>');
 	}
+
+	if (length <= 0)
+		return;
+
+	/*
+	 * Decode payload if necessary.
+	*/
+#ifndef BGP_PORT
+#define BGP_PORT	179
+#endif
+	bp += (tp->th_off * 4);
+	if (sport == BGP_PORT || dport == BGP_PORT)
+		bgp_print(bp, length);
 	return;
 bad:
 	fputs("[bad opt]", stdout);