print-snmp.c

来自「TCPDUMP的C语言源代码,是在数据链路层的应用」· C语言 代码 · 共 1,905 行 · 第 1/3 页

		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;

trunc:
	fputs("[|snmp]", stdout);
	return -1;
}

/*
 * 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 int
asn1_print(struct be *elem)
{
	u_char *p = (u_char *)elem->data.raw;
	u_int32_t asnlen = elem->asnlen;
	u_int32_t i;

	switch (elem->type) {

	case BE_OCTET:
		TCHECK2(*p, asnlen);
		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 (!sflag && !nflag && asnlen > 2) {
			struct obj_abrev *a = &obj_abrev_list[0];
			size_t a_len = strlen(a->oid);
			for (; a->node; a++) {
				TCHECK2(*p, a_len);
				if (memcmp(a->oid, (char *)p, a_len) == 0) {
					objp = a->node->child;
					i -= strlen(a->oid);
					p += strlen(a->oid);
					fputs(a->prefix, stdout);
					first = 1;
					break;
				}
			}
		}

		for (; !sflag && i-- > 0; p++) {
			TCHECK(*p);
			o = (o << ASN_SHIFT7) + (*p & ~ASN_BIT8);
			if (*p & ASN_LONGLEN)
			        continue;

			/*
			 * first subitem encodes two items with 1st*OIDMUX+2nd
			 * (see X.690:1997 clause 8.19 for the details)
			 */
			if (first < 0) {
			        int s;
				if (!nflag)
					objp = mibroot;
				first = 0;
				s = o / OIDMUX;
				if (s > 2) s = 2;
				OBJ_PRINT(s, first);
				o -= s * 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("%u", elem->data.uns);
		break;

	case BE_UNS64: {	/* idea borrowed from by Marshall Rose */
	        double d;
		int j, carry;
		char *cpf, *cpl, last[6], first[30];
		if (elem->data.uns64.high == 0) {
		        printf("%u", elem->data.uns64.low);
		        break;
		}
		d = elem->data.uns64.high * 4294967296.0;	/* 2^32 */
		if (elem->data.uns64.high <= 0x1fffff) {
		        d += elem->data.uns64.low;
#if 0 /*is looks illegal, but what is the intention?*/
			printf("%.f", d);
#else
			printf("%f", d);
#endif
			break;
		}
		d += (elem->data.uns64.low & 0xfffff000);
#if 0 /*is looks illegal, but what is the intention?*/
		snprintf(first, sizeof(first), "%.f", d);
#else
		snprintf(first, sizeof(first), "%f", d);
#endif
		snprintf(last, sizeof(last), "%5.5d",
		    elem->data.uns64.low & 0xfff);
		for (carry = 0, cpf = first+strlen(first)-1, cpl = last+4;
		     cpl >= last;
		     cpf--, cpl--) {
		        j = carry + (*cpf - '0') + (*cpl - '0');
			if (j > 9) {
			        j -= 10;
				carry = 1;
			} else {
			        carry = 0;
		        }
			*cpf = j + '0';
		}
		fputs(first, stdout);
		break;
	}

	case BE_STR: {
		register int printable = 1, first = 1;
		const u_char *p = elem->data.str;
		TCHECK2(*p, asnlen);
		for (i = asnlen; printable && i-- > 0; p++)
			printable = isprint(*p) || isspace(*p);
		p = elem->data.str;
		if (printable) {
			putchar('"');
			if (fn_printn(p, asnlen, snapend)) {
				putchar('"');
				goto trunc;
			}
			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:
		if (asnlen != ASNLEN_INETADDR)
			printf("[inetaddr len!=%d]", ASNLEN_INETADDR);
		TCHECK2(*p, asnlen);
		for (i = asnlen; i-- != 0; p++) {
			printf((i == asnlen-1) ? "%u" : ".%u", *p);
		}
		break;

	case BE_NOSUCHOBJECT:
	case BE_NOSUCHINST:
	case BE_ENDOFMIBVIEW:
	        printf("[%s]", Class[EXCEPTIONS].Id[elem->id]);
		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;
	}
	return 0;

trunc:
	fputs("[|snmp]", stdout);
	return -1;
}

#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);
			if (asn1_print(&elem) < 0)
				return;
			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

#ifdef LIBSMI

struct smi2be {
    SmiBasetype basetype;
    int be;
};

static struct smi2be smi2betab[] = {
    { SMI_BASETYPE_INTEGER32,		BE_INT },
    { SMI_BASETYPE_OCTETSTRING,		BE_STR },
    { SMI_BASETYPE_OCTETSTRING,		BE_INETADDR },
    { SMI_BASETYPE_OBJECTIDENTIFIER,	BE_OID },
    { SMI_BASETYPE_UNSIGNED32,		BE_UNS },
    { SMI_BASETYPE_INTEGER64,		BE_NONE },
    { SMI_BASETYPE_UNSIGNED64,		BE_UNS64 },
    { SMI_BASETYPE_FLOAT32,		BE_NONE },
    { SMI_BASETYPE_FLOAT64,		BE_NONE },
    { SMI_BASETYPE_FLOAT128,		BE_NONE },
    { SMI_BASETYPE_ENUM,		BE_INT },
    { SMI_BASETYPE_BITS,		BE_STR },
    { SMI_BASETYPE_UNKNOWN,		BE_NONE }
};

static int
smi_decode_oid(struct be *elem, unsigned int *oid,
	       unsigned int oidsize, unsigned int *oidlen)
{
	u_char *p = (u_char *)elem->data.raw;
	u_int32_t asnlen = elem->asnlen;
	int o = 0, first = -1, i = asnlen;

	for (*oidlen = 0; sflag && i-- > 0; p++) {
		TCHECK(*p);
	        o = (o << ASN_SHIFT7) + (*p & ~ASN_BIT8);
		if (*p & ASN_LONGLEN)
		    continue;

		/*
		 * first subitem encodes two items with 1st*OIDMUX+2nd
		 * (see X.690:1997 clause 8.19 for the details)
		 */
		if (first < 0) {
		        first = 0;
			if (*oidlen < oidsize) {
			    oid[*oidlen] = o / OIDMUX;
			    if (oid[*oidlen] > 2) oid[*oidlen] = 2;
			}
			o -= oid[*oidlen] * OIDMUX;
			if (*oidlen < oidsize) (*oidlen)++;
		}
		if (*oidlen < oidsize) {
			oid[(*oidlen)++] = o;
		}
		o = 0;
	}
	return 0;

trunc:
	fputs("[|snmp]", stdout);
	return -1;
}

static int smi_check_type(SmiBasetype basetype, int be)
{
    int i;

    for (i = 0; smi2betab[i].basetype != SMI_BASETYPE_UNKNOWN; i++) {
	if (smi2betab[i].basetype == basetype && smi2betab[i].be == be) {
	    return 1;
	}
    }

    return 0;
}

static int smi_check_a_range(SmiType *smiType, SmiRange *smiRange,
			     struct be *elem)
{
    int ok = 1;

    switch (smiType->basetype) {
    case SMI_BASETYPE_OBJECTIDENTIFIER:
    case SMI_BASETYPE_OCTETSTRING:
	if (smiRange->minValue.value.unsigned32
	    == smiRange->maxValue.value.unsigned32) {
	    ok = (elem->asnlen == smiRange->minValue.value.unsigned32);
	} else {
	    ok = (elem->asnlen >= smiRange->minValue.value.unsigned32
		  && elem->asnlen <= smiRange->maxValue.value.unsigned32);
	}
	break;

    case SMI_BASETYPE_INTEGER32:
	ok = (elem->data.integer >= smiRange->minValue.value.integer32
	      && elem->data.integer <= smiRange->maxValue.value.integer32);
	break;

    case SMI_BASETYPE_UNSIGNED32:
	ok = (elem->data.uns >= smiRange->minValue.value.unsigned32
	      && elem->data.uns <= smiRange->maxValue.value.unsigned32);
	break;

    case SMI_BASETYPE_UNSIGNED64:
	/* XXX */
	break;

	/* case SMI_BASETYPE_INTEGER64: SMIng */
	/* case SMI_BASETYPE_FLOAT32: SMIng */
	/* case SMI_BASETYPE_FLOAT64: SMIng */
	/* case SMI_BASETYPE_FLOAT128: SMIng */

    case SMI_BASETYPE_ENUM:
    case SMI_BASETYPE_BITS:
    case SMI_BASETYPE_UNKNOWN:
	ok = 1;
	break;

    default:
	ok = 0;
	break;
    }

    return ok;
}

static int smi_check_range(SmiType *smiType, struct be *elem)
{
        SmiRange *smiRange;
	int ok = 1;

	for (smiRange = smiGetFirstRange(smiType);
	     smiRange;
	     smiRange = smiGetNextRange(smiRange)) {

	    ok = smi_check_a_range(smiType, smiRange, elem);

	    if (ok) {
		break;
	    }
	}

	if (ok) {
	    SmiType *parentType;
	    parentType = smiGetParentType(smiType);
	    if (parentType) {
		ok = smi_check_range(parentType, elem);
	    }
	}

	return ok;
}

static SmiNode *smi_print_variable(struct be *elem, int *status)
{
	unsigned int oid[128], oidlen;
	SmiNode *smiNode = NULL;
	unsigned int i;

	*status = smi_decode_oid(elem, oid, sizeof(oid)/sizeof(unsigned int),
	    &oidlen);
	if (*status < 0)
		return NULL;
	smiNode = smiGetNodeByOID(oidlen, oid);
	if (! smiNode) {
		*status = asn1_print(elem);
		return NULL;
	}
	if (vflag) {
		fputs(smiGetNodeModule(smiNode)->name, stdout);
		fputs("::", stdout);
	}
	fputs(smiNode->name, stdout);
	if (smiNode->oidlen < oidlen) {
	        for (i = smiNode->oidlen; i < oidlen; i++) {
		        printf(".%u", oid[i]);
		}
	}
	*status = 0;
	return smiNode;
}

static int
smi_print_value(SmiNode *smiNode, u_char pduid, struct be *elem)
{
	unsigned int i, oid[128], oidlen;
	SmiType *smiType;
	SmiNamedNumber *nn;
	int done = 0;

	if (! smiNode || ! (smiNode->nodekind
			    & (SMI_NODEKIND_SCALAR | SMI_NODEKIND_COLUMN))) {
	    return asn1_print(elem);
	}

	if (elem->type == BE_NOSUCHOBJECT
	    || elem->type == BE_NOSUCHINST
	    || elem->type == BE_ENDOFMIBVIEW) {
	    return asn1_print(elem);
	}

	if (NOTIFY_CLASS(pduid) && smiNode->access < SMI_ACCESS_NOTIFY) {
	    fputs("[notNotifyable]", stdout);
	}

	if (READ_CLASS(pduid) && smiNode->access < SMI_ACCESS_READ_ONLY) {
	    fputs("[notReadable]", stdout);
	}

	if (WRITE_CLASS(pduid) && smiNode->access < SMI_ACCESS_READ_WRITE) {
	    fputs("[notWritable]", stdout);
	}

	if (RESPONSE_CLASS(pduid)
	    && smiNode->access == SMI_ACCESS_NOT_ACCESSIBLE) {
	    fputs("[noAccess]", stdout);
	}

	smiType = smiGetNodeType(smiNode);
	if (! smiType) {
	    return asn1_print(elem);
	}

	if (! smi_check_type(smiType->basetype, elem->type)) {
	    fputs("[wrongType]", stdout);
	}

	if (! smi_check_range(smiType, elem)) {
	    fputs("[outOfRange]", stdout);
	}

	/* resolve bits to named bits */

	/* check whether instance identifier is valid */

	/* apply display hints (integer, octetstring) */

	/* convert instance identifier to index type values */

	switch (elem->type) {
	case BE_OID:
	        if (smiType->basetype == SMI_BASETYPE_BITS) {
		        /* print bit labels */
		} else {
		        smi_decode_oid(elem, oid,
				       sizeof(oid)/sizeof(unsigned int),
				       &oidlen);
			smiNode = smiGetNodeByOID(oidlen, oid);
			if (smiNode) {
			        if (vflag) {
					fputs(smiGetNodeModule(smiNode)->name, stdout);
					fputs("::", stdout);
				}
				fputs(smiNode->name, stdout);
				if (smiNode->oidlen < oidlen) {
				        for (i = smiNode->oidlen;
					     i < oidlen; i++) {
					        printf(".%u", oid[i]);
					}
				}
				done++;
			}
		}
		break;

	case BE_INT:
	        if (smiType->basetype == SMI_BASETYPE_ENUM) {
		        for (nn = smiGetFirstNamedNumber(smiType);
			     nn;
			     nn = smiGetNextNamedNumber(nn)) {
			         if (nn->value.value.integer32
				     == elem->data.integer) {
				         fputs(nn->name, stdout);
					 printf("(%d)", elem->data.integer);
					 done++;
					 break;
				}
			}
		}
		break;
	}

	if (! done) {
		return asn1_print(elem);
	}
	return 0;
}
#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)
{
	struct be elem;
	int count = 0, ind;
#ifdef LIBSMI
	SmiNode *smiNode = NULL;
#endif
	int status;

	/* 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 ((u_int)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;

		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;
		}
#ifdef LIBSMI
		smiNode = smi_print_variable(&elem, &status);
#else
		status = asn1_print(&elem);
#endif
		if (status < 0)
			return;
		length -= count;
		np += count;

		if (pduid != GETREQ && pduid != GETNEXTREQ
		    && pduid != GETBULKREQ)
			fputs("=", stdout);

		/* objVal (ANY) */
		if ((count = asn1_parse(np, length, &elem)) < 0)
			return;
		if (pduid == GETREQ || pduid == GETNEXTREQ
		    || pduid == GETBULKREQ) {
			if (elem.type != BE_NULL) {