Virgin import of unmodified tcpdump v3.2.1 distribution from LBL.

Obtained from: ftp://ftp.ee.lbl.gov/tcpdump.tar.Z on 19-Aug-1996.

1 files changed, 1039 insertions, 0 deletions

diff --git a/contrib/tcpdump/print-snmp.c b/contrib/tcpdump/print-snmp.c
new file mode 100644
index 0000000..0bc856a
--- /dev/null
+++ b/contrib/tcpdump/print-snmp.c
@@ -0,0 +1,1039 @@
+/*
+ * Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are permitted
+ * provided that the above copyright notice and this paragraph are
+ * duplicated in all such forms and that any documentation,
+ * advertising materials, and other materials related to such
+ * distribution and use acknowledge that the software was developed
+ * by John Robert LoVerso.
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * This implementation has been influenced by the CMU SNMP release,
+ * by Steve Waldbusser.  However, this shares no code with that system.
+ * Additional ASN.1 insight gained from Marshall T. Rose's _The_Open_Book_.
+ * Earlier forms of this implementation were derived and/or inspired by an
+ * awk script originally written by C. Philip Wood of LANL (but later
+ * heavily modified by John Robert LoVerso).  The copyright notice for
+ * that work is preserved below, even though it may not rightly apply
+ * to this file.
+ *
+ * This started out as a very simple program, but the incremental decoding
+ * (into the BE structure) complicated things.
+ *
+ #			Los Alamos National Laboratory
+ #
+ #	Copyright, 1990.  The Regents of the University of California.
+ #	This software was produced under a U.S. Government contract
+ #	(W-7405-ENG-36) by Los Alamos National Laboratory, which is
+ #	operated by the	University of California for the U.S. Department
+ #	of Energy.  The U.S. Government is licensed to use, reproduce,
+ #	and distribute this software.  Permission is granted to the
+ #	public to copy and use this software without charge, provided
+ #	that this Notice and any statement of authorship are reproduced
+ #	on all copies.  Neither the Government nor the University makes
+ #	any warranty, express or implied, or assumes any liability or
+ #	responsibility for the use of this software.
+ #	@(#)snmp.awk.x	1.1 (LANL) 1/15/90
+ */
+#ifndef lint
+static char rcsid[] =
+    "@(#) $Id: print-snmp.c,v 3.10 91/01/17 01:18:13 loverso Exp Locker: loverso $ (jlv)";
+#endif
+
+#include <sys/param.h>
+#include <sys/time.h>
+
+#include <stdio.h>
+#include <ctype.h>
+#include <string.h>
+
+#include "interface.h"
+#include "addrtoname.h"
+
+/*
+ * Universal ASN.1 types
+ * (we only care about the tag values for those allowed in the Internet SMI)
+ */
+char *Universal[] = {
+	"U-0",
+	"Boolean",
+	"Integer",
+#define INTEGER 2
+	"Bitstring",
+	"String",
+#define STRING 4
+	"Null",
+#define ASN_NULL 5
+	"ObjID",
+#define OBJECTID 6
+	"ObjectDes",
+	"U-8","U-9","U-10","U-11",	/* 8-11 */
+	"U-12","U-13","U-14","U-15",	/* 12-15 */
+	"Sequence",
+#define SEQUENCE 16
+	"Set"
+};
+
+/*
+ * Application-wide ASN.1 types from the Internet SMI and their tags
+ */
+char *Application[] = {
+	"IpAddress",
+#define IPADDR 0
+	"Counter",
+#define COUNTER 1
+	"Gauge",
+#define GAUGE 2
+	"TimeTicks",
+#define TIMETICKS 3
+	"Opaque"
+};
+
+/*
+ * Context-specific ASN.1 types for the SNMP PDUs and their tags
+ */
+char *Context[] = {
+	"GetRequest",
+#define GETREQ 0
+	"GetNextRequest",
+#define GETNEXTREQ 1
+	"GetResponse",
+#define GETRESP 2
+	"SetRequest",
+#define SETREQ 3
+	"Trap"
+#define TRAP 4
+};
+
+/*
+ * Private ASN.1 types
+ * The Internet SMI does not specify any
+ */
+char *Private[] = {
+	"P-0"
+};
+
+/*
+ * error-status values for any SNMP PDU
+ */
+char *ErrorStatus[] = {
+	"noError",
+	"tooBig",
+	"noSuchName",
+	"badValue",
+	"readOnly",
+	"genErr"
+};
+#define DECODE_ErrorStatus(e) \
+	( e >= 0 && e <= sizeof(ErrorStatus)/sizeof(ErrorStatus[0]) \
+	? ErrorStatus[e] : (sprintf(errbuf, "err=%u", e), errbuf))
+
+/*
+ * generic-trap values in the SNMP Trap-PDU
+ */
+char *GenericTrap[] = {
+	"coldStart",
+	"warmStart",
+	"linkDown",
+	"linkUp",
+	"authenticationFailure",
+	"egpNeighborLoss",
+	"enterpriseSpecific"
+#define GT_ENTERPRISE 7
+};
+#define DECODE_GenericTrap(t) \
+	( t >= 0 && t <= sizeof(GenericTrap)/sizeof(GenericTrap[0]) \
+	? GenericTrap[t] : (sprintf(buf, "gt=%d", t), buf))
+
+/*
+ * ASN.1 type class table
+ * Ties together the preceding Universal, Application, Context, and Private
+ * type definitions.
+ */
+#define defineCLASS(x) { "x", x, sizeof(x)/sizeof(x[0]) } /* not ANSI-C */
+struct {
+	char	*name;
+	char	**Id;
+	    int	numIDs;
+    } Class[] = {
+	defineCLASS(Universal),
+#define	UNIVERSAL	0
+	defineCLASS(Application),
+#define	APPLICATION	1
+	defineCLASS(Context),
+#define	CONTEXT		2
+	defineCLASS(Private),
+#define	PRIVATE		3
+};
+
+/*
+ * defined forms for ASN.1 types
+ */
+char *Form[] = {
+	"Primitive",
+#define PRIMITIVE	0
+	"Constructed",
+#define CONSTRUCTED	1
+};
+
+/*
+ * A structure for the OID tree for the compiled-in MIB.
+ * This is stored as a general-order tree.
+ */
+struct obj {
+	char	*desc;			/* name of object */
+	u_char	oid;			/* sub-id following parent */
+	u_char	type;			/* object type (unused) */
+	struct obj *child, *next;	/* child and next sibling pointers */
+} *objp = NULL;
+
+/*
+ * Include the compiled in SNMP MIB.  "mib.h" is produced by feeding
+ * RFC-1156 format files into "makemib".  "mib.h" MUST define at least
+ * a value for `mibroot'.
+ *
+ * In particular, this is gross, as this is including initialized structures,
+ * and by right shouldn't be an "include" file.
+ */
+#include "mib.h"
+
+/*
+ * This defines a list of OIDs which will be abbreviated on output.
+ * Currently, this includes the prefixes for the Internet MIB, the
+ * private enterprises tree, and the experimental tree.
+ */
+struct obj_abrev {
+	char *prefix;			/* prefix for this abrev */
+	struct obj *node;		/* pointer into object table */
+	char *oid;			/* ASN.1 encoded OID */
+} obj_abrev_list[] = {
+#ifndef NO_ABREV_MIB
+	/* .iso.org.dod.internet.mgmt.mib */
+	{ "",	&_mib_obj,		"\53\6\1\2\1" },
+#endif
+#ifndef NO_ABREV_ENTER
+	/* .iso.org.dod.internet.private.enterprises */
+	{ "E:",	&_enterprises_obj,	"\53\6\1\4\1" },
+#endif
+#ifndef NO_ABREV_EXPERI
+	/* .iso.org.dod.internet.experimental */
+	{ "X:",	&_experimental_obj,	"\53\6\1\3" },
+#endif
+	{ 0,0,0 }
+};
+
+/*
+ * This is used in the OID print routine to walk down the object tree
+ * rooted at `mibroot'.
+ */
+#define OBJ_PRINT(o, suppressdot) \
+{ \
+	if (objp) { \
+		do { \
+			if ((o) == objp->oid) \
+				break; \
+		} while ((objp = objp->next) != NULL); \
+	} \
+	if (objp) { \
+		printf(suppressdot?"%s":".%s", objp->desc); \
+		objp = objp->child; \
+	} else \
+		printf(suppressdot?"%u":".%u", (o)); \
+}
+
+/*
+ * This is the definition for the Any-Data-Type storage used purely for
+ * temporary internal representation while decoding an ASN.1 data stream.
+ */
+struct be {
+	u_int32_t asnlen;
+	union {
+		caddr_t raw;
+		int32_t integer;
+		u_int32_t uns;
+		const u_char *str;
+	} data;
+	u_short id;
+	u_char form, class;		/* tag info */
+	u_char type;
+#define BE_ANY		255
+#define BE_NONE		0
+#define BE_NULL		1
+#define BE_OCTET	2
+#define BE_OID		3
+#define BE_INT		4
+#define BE_UNS		5
+#define BE_STR		6
+#define BE_SEQ		7
+#define BE_INETADDR	8
+#define BE_PDU		9
+};
+
+/*
+ * Defaults for SNMP PDU components
+ */
+#define DEF_COMMUNITY "public"
+#define DEF_VERSION 0
+
+/*
+ * constants for ASN.1 decoding
+ */
+#define OIDMUX 40
+#define ASNLEN_INETADDR 4
+#define ASN_SHIFT7 7
+#define ASN_SHIFT8 8
+#define ASN_BIT8 0x80
+#define ASN_LONGLEN 0x80
+
+#define ASN_ID_BITS 0x1f
+#define ASN_FORM_BITS 0x20
+#define ASN_FORM_SHIFT 5
+#define ASN_CLASS_BITS 0xc0
+#define ASN_CLASS_SHIFT 6
+
+#define ASN_ID_EXT 0x1f		/* extension ID in tag field */
+
+/*
+ * truncated==1 means the packet was complete, but we don't have all of
+ * it to decode.
+ */
+static int truncated;
+#define ifNotTruncated if (truncated) fputs("[|snmp]", stdout); else
+
+/*
+ * This decodes the next ASN.1 object in the stream pointed to by "p"
+ * (and of real-length "len") and stores the intermediate data in the
+ * provided BE object.
+ *
+ * This returns -l if it fails (i.e., the ASN.1 stream is not valid).
+ * O/w, this returns the number of bytes parsed from "p".
+ */
+static int
+asn1_parse(register const u_char *p, u_int len, struct be *elem)
+{
+	u_char form, class, id;
+	int i, hdr;
+
+	elem->asnlen = 0;
+	elem->type = BE_ANY;
+	if (len < 1) {
+		ifNotTruncated puts("[nothing to parse], stdout");
+		return -1;
+	}
+
+	/*
+	 * it would be nice to use a bit field, but you can't depend on them.
+	 *  +---+---+---+---+---+---+---+---+
+	 *  + class |frm|        id         |
+	 *  +---+---+---+---+---+---+---+---+
+	 *    7   6   5   4   3   2   1   0
+	 */
+	id = *p & ASN_ID_BITS;		/* lower 5 bits, range 00-1f */
+#ifdef notdef
+	form = (*p & 0xe0) >> 5;	/* move upper 3 bits to lower 3 */
+	class = form >> 1;		/* bits 7&6 -> bits 1&0, range 0-3 */
+	form &= 0x1;			/* bit 5 -> bit 0, range 0-1 */
+#else
+	form = (*p & ASN_FORM_BITS) >> ASN_FORM_SHIFT;
+	class = (*p & ASN_CLASS_BITS) >> ASN_CLASS_SHIFT;
+#endif
+	elem->form = form;
+	elem->class = class;
+	elem->id = id;
+	if (vflag)
+		printf("|%.2x", *p);
+	p++; len--; hdr = 1;
+	/* extended tag field */
+	if (id == ASN_ID_EXT) {
+		for (id = 0; *p & ASN_BIT8 && len > 0; len--, hdr++, p++) {
+			if (vflag)
+				printf("|%.2x", *p);
+			id = (id << 7) | (*p & ~ASN_BIT8);
+		}
+		if (len == 0 && *p & ASN_BIT8) {
+			ifNotTruncated fputs("[Xtagfield?]", stdout);
+			return -1;
+		}
+		elem->id = id = (id << 7) | *p;
+		--len;
+		++hdr;
+		++p;
+	}
+	if (len < 1) {
+		ifNotTruncated fputs("[no asnlen]", stdout);
+		return -1;
+	}
+	elem->asnlen = *p;
+	if (vflag)
+		printf("|%.2x", *p);
+	p++; len--; hdr++;
+	if (elem->asnlen & ASN_BIT8) {
+		int noct = elem->asnlen % ASN_BIT8;
+		elem->asnlen = 0;
+		if (len < noct) {
+			ifNotTruncated printf("[asnlen? %d<%d]", len, noct);
+			return -1;
+		}
+		for (; noct-- > 0; len--, hdr++) {
+			if (vflag)
+				printf("|%.2x", *p);
+			elem->asnlen = (elem->asnlen << ASN_SHIFT8) | *p++;
+		}
+	}
+	if (len < elem->asnlen) {
+		if (!truncated) {
+			printf("[len%d<asnlen%u]", len, elem->asnlen);
+			return -1;
+		}
+		/* maybe should check at least 4? */
+		elem->asnlen = len;
+	}
+	if (form >= sizeof(Form)/sizeof(Form[0])) {
+		ifNotTruncated printf("[form?%d]", form);
+		return -1;
+	}
+	if (class >= sizeof(Class)/sizeof(Class[0])) {
+		ifNotTruncated printf("[class?%c/%d]", *Form[form], class);
+		return -1;
+	}
+	if (id >= Class[class].numIDs) {
+		ifNotTruncated printf("[id?%c/%s/%d]", *Form[form],
+			Class[class].name, id);
+		return -1;
+	}
+
+	switch (form) {
+	case PRIMITIVE:
+		switch (class) {
+		case UNIVERSAL:
+			switch (id) {
+			case STRING:
+				elem->type = BE_STR;
+				elem->data.str = p;
+				break;
+
+			case INTEGER: {
+				register int32_t data;
+				elem->type = BE_INT;
+				data = 0;
+
+				if (*p & ASN_BIT8)	/* negative */
+					data = -1;
+				for (i = elem->asnlen; i-- > 0; p++)
+					data = (data << ASN_SHIFT8) | *p;
+				elem->data.integer = data;
+				break;
+			}
+
+			case OBJECTID:
+				elem->type = BE_OID;
+				elem->data.raw = (caddr_t)p;
+				break;
+
+			case ASN_NULL:
+				elem->type = BE_NULL;
+				elem->data.raw = NULL;
+				break;
+
+			default:
+				elem->type = BE_OCTET;
+				elem->data.raw = (caddr_t)p;
+				printf("[P/U/%s]",
+					Class[class].Id[id]);
+				break;
+			}
+			break;
+
+		case APPLICATION:
+			switch (id) {
+			case IPADDR:
+				elem->type = BE_INETADDR;
+				elem->data.raw = (caddr_t)p;
+				break;
+
+			case COUNTER:
+			case GAUGE:
+			case TIMETICKS: {
+				register u_int32_t data;
+				elem->type = BE_UNS;
+				data = 0;
+				for (i = elem->asnlen; i-- > 0; p++)
+					data = (data << 8) + *p;
+				elem->data.uns = data;
+				break;
+			}
+
+			default:
+				elem->type = BE_OCTET;
+				elem->data.raw = (caddr_t)p;
+				printf("[P/A/%s]",
+					Class[class].Id[id]);
+				break;
+			}
+			break;
+
+		default:
+			elem->type = BE_OCTET;
+			elem->data.raw = (caddr_t)p;
+			printf("[P/%s/%s]",
+				Class[class].name, Class[class].Id[id]);
+			break;
+		}
+		break;
+
+	case CONSTRUCTED:
+		switch (class) {
+		case UNIVERSAL:
+			switch (id) {
+			case SEQUENCE:
+				elem->type = BE_SEQ;
+				elem->data.raw = (caddr_t)p;
+				break;
+
+			default:
+				elem->type = BE_OCTET;
+				elem->data.raw = (caddr_t)p;
+				printf("C/U/%s", Class[class].Id[id]);
+				break;
+			}
+			break;
+
+		case CONTEXT:
+			elem->type = BE_PDU;
+			elem->data.raw = (caddr_t)p;
+			break;
+
+		default:
+			elem->type = BE_OCTET;
+			elem->data.raw = (caddr_t)p;
+			printf("C/%s/%s",
+				Class[class].name, Class[class].Id[id]);
+			break;
+		}
+		break;
+	}
+	p += elem->asnlen;
+	len -= elem->asnlen;
+	return elem->asnlen + hdr;
+}
+
+/*
+ * Display the ASN.1 object represented by the BE object.
+ * This used to be an integral part of asn1_parse() before the intermediate
+ * BE form was added.
+ */
+static void
+asn1_print(struct be *elem)
+{
+	u_char *p = (u_char *)elem->data.raw;
+	u_int32_t asnlen = elem->asnlen;
+	int i;
+
+	switch (elem->type) {
+
+	case BE_OCTET:
+		for (i = asnlen; i-- > 0; p++);
+			printf("_%.2x", *p);
+		break;
+
+	case BE_NULL:
+		break;
+
+	case BE_OID: {
+	int o = 0, first = -1, i = asnlen;
+
+		if (!nflag && asnlen > 2) {
+			struct obj_abrev *a = &obj_abrev_list[0];
+			for (; a->node; a++) {
+				if (!memcmp(a->oid, (char *)p,
+				    strlen(a->oid))) {
+					objp = a->node->child;
+					i -= strlen(a->oid);
+					p += strlen(a->oid);
+					fputs(a->prefix, stdout);
+					first = 1;
+					break;
+				}
+			}
+		}
+		for (; i-- > 0; p++) {
+			o = (o << ASN_SHIFT7) + (*p & ~ASN_BIT8);
+			if (*p & ASN_LONGLEN)
+				continue;
+
+			/*
+			 * first subitem encodes two items with 1st*OIDMUX+2nd
+			 */
+			if (first < 0) {
+				if (!nflag)
+					objp = mibroot;
+				first = 0;
+				OBJ_PRINT(o/OIDMUX, first);
+				o %= OIDMUX;
+			}
+			OBJ_PRINT(o, first);
+			if (--first < 0)
+				first = 0;
+			o = 0;
+		}
+		break;
+	}
+
+	case BE_INT:
+		printf("%d", elem->data.integer);
+		break;
+
+	case BE_UNS:
+		printf("%d", elem->data.uns);
+		break;
+
+	case BE_STR: {
+		register int printable = 1, first = 1;
+		const u_char *p = elem->data.str;
+		for (i = asnlen; printable && i-- > 0; p++)
+			printable = isprint(*p) || isspace(*p);
+		p = elem->data.str;
+		if (printable) {
+			putchar('"');
+			(void)fn_print(p, p + asnlen);
+			putchar('"');
+		} else
+			for (i = asnlen; i-- > 0; p++) {
+				printf(first ? "%.2x" : "_%.2x", *p);
+				first = 0;
+			}
+		break;
+	}
+
+	case BE_SEQ:
+		printf("Seq(%u)", elem->asnlen);
+		break;
+
+	case BE_INETADDR: {
+		char sep;
+		if (asnlen != ASNLEN_INETADDR)
+			printf("[inetaddr len!=%d]", ASNLEN_INETADDR);
+		sep='[';
+		for (i = asnlen; i-- > 0; p++) {
+			printf("%c%u", sep, *p);
+			sep='.';
+		}
+		putchar(']');
+		break;
+	}
+
+	case BE_PDU:
+		printf("%s(%u)",
+			Class[CONTEXT].Id[elem->id], elem->asnlen);
+		break;
+
+	case BE_ANY:
+		fputs("[BE_ANY!?]", stdout);
+		break;
+
+	default:
+		fputs("[be!?]", stdout);
+		break;
+	}
+}
+
+#ifdef notdef
+/*
+ * This is a brute force ASN.1 printer: recurses to dump an entire structure.
+ * This will work for any ASN.1 stream, not just an SNMP PDU.
+ *
+ * By adding newlines and spaces at the correct places, this would print in
+ * Rose-Normal-Form.
+ *
+ * This is not currently used.
+ */
+static void
+asn1_decode(u_char *p, u_int length)
+{
+	struct be elem;
+	int i = 0;
+
+	while (i >= 0 && length > 0) {
+		i = asn1_parse(p, length, &elem);
+		if (i >= 0) {
+			fputs(" ", stdout);
+			asn1_print(&elem);
+			if (elem.type == BE_SEQ || elem.type == BE_PDU) {
+				fputs(" {", stdout);
+				asn1_decode(elem.data.raw, elem.asnlen);
+				fputs(" }", stdout);
+			}
+			length -= i;
+			p += i;
+		}
+	}
+}
+#endif
+
+/*
+ * General SNMP header
+ *	SEQUENCE {
+ *		version INTEGER {version-1(0)},
+ *		community OCTET STRING,
+ *		data ANY	-- PDUs
+ *	}
+ * PDUs for all but Trap: (see rfc1157 from page 15 on)
+ *	SEQUENCE {
+ *		request-id INTEGER,
+ *		error-status INTEGER,
+ *		error-index INTEGER,
+ *		varbindlist SEQUENCE OF
+ *			SEQUENCE {
+ *				name ObjectName,
+ *				value ObjectValue
+ *			}
+ *	}
+ * PDU for Trap:
+ *	SEQUENCE {
+ *		enterprise OBJECT IDENTIFIER,
+ *		agent-addr NetworkAddress,
+ *		generic-trap INTEGER,
+ *		specific-trap INTEGER,
+ *		time-stamp TimeTicks,
+ *		varbindlist SEQUENCE OF
+ *			SEQUENCE {
+ *				name ObjectName,
+ *				value ObjectValue
+ *			}
+ *	}
+ */
+
+/*
+ * Decode SNMP varBind
+ */
+static void
+varbind_print(u_char pduid, const u_char *np, u_int length, int error)
+{
+	struct be elem;
+	int count = 0, ind;
+
+	/* Sequence of varBind */
+	if ((count = asn1_parse(np, length, &elem)) < 0)
+		return;
+	if (elem.type != BE_SEQ) {
+		fputs("[!SEQ of varbind]", stdout);
+		asn1_print(&elem);
+		return;
+	}
+	if (count < length)
+		printf("[%d extra after SEQ of varbind]", length - count);
+	/* descend */
+	length = elem.asnlen;
+	np = (u_char *)elem.data.raw;
+
+	for (ind = 1; length > 0; ind++) {
+		const u_char *vbend;
+		u_int vblength;
+
+		if (!error || ind == error)
+			fputs(" ", stdout);
+
+		/* Sequence */
+		if ((count = asn1_parse(np, length, &elem)) < 0)
+			return;
+		if (elem.type != BE_SEQ) {
+			fputs("[!varbind]", stdout);
+			asn1_print(&elem);
+			return;
+		}
+		vbend = np + count;
+		vblength = length - count;
+		/* descend */
+		length = elem.asnlen;
+		np = (u_char *)elem.data.raw;
+
+		/* objName (OID) */
+		if ((count = asn1_parse(np, length, &elem)) < 0)
+			return;
+		if (elem.type != BE_OID) {
+			fputs("[objName!=OID]", stdout);
+			asn1_print(&elem);
+			return;
+		}
+		if (!error || ind == error)
+			asn1_print(&elem);
+		length -= count;
+		np += count;
+
+		if (pduid != GETREQ && pduid != GETNEXTREQ && !error)
+				fputs("=", stdout);
+
+		/* objVal (ANY) */
+		if ((count = asn1_parse(np, length, &elem)) < 0)
+			return;
+		if (pduid == GETREQ || pduid == GETNEXTREQ) {
+			if (elem.type != BE_NULL) {
+				fputs("[objVal!=NULL]", stdout);
+				asn1_print(&elem);
+			}
+		} else
+			if (error && ind == error && elem.type != BE_NULL)
+				fputs("[err objVal!=NULL]", stdout);
+			if (!error || ind == error)
+				asn1_print(&elem);
+
+		length = vblength;
+		np = vbend;
+	}
+}
+
+/*
+ * Decode SNMP PDUs: GetRequest, GetNextRequest, GetResponse, and SetRequest
+ */
+static void
+snmppdu_print(u_char pduid, const u_char *np, u_int length)
+{
+	struct be elem;
+	int count = 0, error;
+
+	/* reqId (Integer) */
+	if ((count = asn1_parse(np, length, &elem)) < 0)
+		return;
+	if (elem.type != BE_INT) {
+		fputs("[reqId!=INT]", stdout);
+		asn1_print(&elem);
+		return;
+	}
+	/* ignore the reqId */
+	length -= count;
+	np += count;
+
+	/* errorStatus (Integer) */
+	if ((count = asn1_parse(np, length, &elem)) < 0)
+		return;
+	if (elem.type != BE_INT) {
+		fputs("[errorStatus!=INT]", stdout);
+		asn1_print(&elem);
+		return;
+	}
+	error = 0;
+	if ((pduid == GETREQ || pduid == GETNEXTREQ)
+	    && elem.data.integer != 0) {
+		char errbuf[10];
+		printf("[errorStatus(%s)!=0]",
+			DECODE_ErrorStatus(elem.data.integer));
+	} else if (elem.data.integer != 0) {
+		char errbuf[10];
+		printf(" %s", DECODE_ErrorStatus(elem.data.integer));
+		error = elem.data.integer;
+	}
+	length -= count;
+	np += count;
+
+	/* errorIndex (Integer) */
+	if ((count = asn1_parse(np, length, &elem)) < 0)
+		return;
+	if (elem.type != BE_INT) {
+		fputs("[errorIndex!=INT]", stdout);
+		asn1_print(&elem);
+		return;
+	}
+	if ((pduid == GETREQ || pduid == GETNEXTREQ)
+	    && elem.data.integer != 0)
+		printf("[errorIndex(%d)!=0]", elem.data.integer);
+	else if (elem.data.integer != 0) {
+		if (!error)
+			printf("[errorIndex(%d) w/o errorStatus]",
+				elem.data.integer);
+		else {
+			printf("@%d", elem.data.integer);
+			error = elem.data.integer;
+		}
+	} else if (error) {
+		fputs("[errorIndex==0]", stdout);
+		error = 0;
+	}
+	length -= count;
+	np += count;
+
+	varbind_print(pduid, np, length, error);
+	return;
+}
+
+/*
+ * Decode SNMP Trap PDU
+ */
+static void
+trap_print(const u_char *np, u_int length)
+{
+	struct be elem;
+	int count = 0, generic;
+
+	putchar(' ');
+
+	/* enterprise (oid) */
+	if ((count = asn1_parse(np, length, &elem)) < 0)
+		return;
+	if (elem.type != BE_OID) {
+		fputs("[enterprise!=OID]", stdout);
+		asn1_print(&elem);
+		return;
+	}
+	asn1_print(&elem);
+	length -= count;
+	np += count;
+
+	putchar(' ');
+
+	/* agent-addr (inetaddr) */
+	if ((count = asn1_parse(np, length, &elem)) < 0)
+		return;
+	if (elem.type != BE_INETADDR) {
+		fputs("[agent-addr!=INETADDR]", stdout);
+		asn1_print(&elem);
+		return;
+	}
+	asn1_print(&elem);
+	length -= count;
+	np += count;
+
+	/* generic-trap (Integer) */
+	if ((count = asn1_parse(np, length, &elem)) < 0)
+		return;
+	if (elem.type != BE_INT) {
+		fputs("[generic-trap!=INT]", stdout);
+		asn1_print(&elem);
+		return;
+	}
+	generic = elem.data.integer;
+	{
+		char buf[10];
+		printf(" %s", DECODE_GenericTrap(generic));
+	}
+	length -= count;
+	np += count;
+
+	/* specific-trap (Integer) */
+	if ((count = asn1_parse(np, length, &elem)) < 0)
+		return;
+	if (elem.type != BE_INT) {
+		fputs("[specific-trap!=INT]", stdout);
+		asn1_print(&elem);
+		return;
+	}
+	if (generic != GT_ENTERPRISE) {
+		if (elem.data.integer != 0)
+			printf("[specific-trap(%d)!=0]", elem.data.integer);
+	} else
+		printf(" s=%d", elem.data.integer);
+	length -= count;
+	np += count;
+
+	putchar(' ');
+
+	/* time-stamp (TimeTicks) */
+	if ((count = asn1_parse(np, length, &elem)) < 0)
+		return;
+	if (elem.type != BE_UNS) {			/* XXX */
+		fputs("[time-stamp!=TIMETICKS]", stdout);
+		asn1_print(&elem);
+		return;
+	}
+	asn1_print(&elem);
+	length -= count;
+	np += count;
+
+	varbind_print (TRAP, np, length, 0);
+	return;
+}
+
+/*
+ * Decode SNMP header and pass on to PDU printing routines
+ */
+void
+snmp_print(const u_char *np, u_int length)
+{
+	struct be elem, pdu;
+	int count = 0;
+
+	truncated = 0;
+
+	/* truncated packet? */
+	if (np + length > snapend) {
+		truncated = 1;
+		length = snapend - np;
+	}
+
+	putchar(' ');
+
+	/* initial Sequence */
+	if ((count = asn1_parse(np, length, &elem)) < 0)
+		return;
+	if (elem.type != BE_SEQ) {
+		fputs("[!init SEQ]", stdout);
+		asn1_print(&elem);
+		return;
+	}
+	if (count < length)
+		printf("[%d extra after iSEQ]", length - count);
+	/* descend */
+	length = elem.asnlen;
+	np = (u_char *)elem.data.raw;
+	/* Version (Integer) */
+	if ((count = asn1_parse(np, length, &elem)) < 0)
+		return;
+	if (elem.type != BE_INT) {
+		fputs("[version!=INT]", stdout);
+		asn1_print(&elem);
+		return;
+	}
+	/* only handle version==0 */
+	if (elem.data.integer != DEF_VERSION) {
+		printf("[version(%d)!=0]", elem.data.integer);
+		return;
+	}
+	length -= count;
+	np += count;
+
+	/* Community (String) */
+	if ((count = asn1_parse(np, length, &elem)) < 0)
+		return;
+	if (elem.type != BE_STR) {
+		fputs("[comm!=STR]", stdout);
+		asn1_print(&elem);
+		return;
+	}
+	/* default community */
+	if (strncmp((char *)elem.data.str, DEF_COMMUNITY,
+	    sizeof(DEF_COMMUNITY) - 1))
+		/* ! "public" */
+		printf("C=%.*s ", (int)elem.asnlen, elem.data.str);
+	length -= count;
+	np += count;
+
+	/* PDU (Context) */
+	if ((count = asn1_parse(np, length, &pdu)) < 0)
+		return;
+	if (pdu.type != BE_PDU) {
+		fputs("[no PDU]", stdout);
+		return;
+	}
+	if (count < length)
+		printf("[%d extra after PDU]", length - count);
+	asn1_print(&pdu);
+	/* descend into PDU */
+	length = pdu.asnlen;
+	np = (u_char *)pdu.data.raw;
+
+	switch (pdu.id) {
+	case TRAP:
+		trap_print(np, length);
+		break;
+	case GETREQ:
+	case GETNEXTREQ:
+	case GETRESP:
+	case SETREQ:
+		snmppdu_print(pdu.id, np, length);
+		break;
+	}
+	return;
+}