freebsd-dev/contrib/tcpdump/print-snmp.c
1998-09-15 19:36:32 +00:00

1044 lines
22 KiB
C

/*
* Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996, 1997
* 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 (c) 1990, 1991, 1993, 1994, 1995, 1996, 1997
# 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 const char rcsid[] =
"@(#) $Header: print-snmp.c,v 1.33 97/06/15 13:20:28 leres Exp $ (LBL)";
#endif
#include <sys/param.h>
#include <sys/time.h>
#include <ctype.h>
#ifdef HAVE_MEMORY_H
#include <memory.h>
#endif
#include <stdio.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 = (u_char)(*p & ASN_FORM_BITS) >> ASN_FORM_SHIFT;
class = (u_char)(*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 ((int)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;
}