Пример #1
0
/*
 * Convert variable bindings from AgentX to SNMP dialect.
 */
int
varbind_convert(struct agentx_pdu *pdu, struct agentx_varbind_hdr *vbhdr,
    struct ber_element **varbind, struct ber_element **iter)
{
	struct ber_oid			 oid;
	u_int32_t			 d;
	u_int64_t			 l;
	int				 slen;
	char				*str;
	struct ber_element		*a;
	int				 ret = AGENTX_ERR_NONE;

	if (snmp_agentx_read_oid(pdu, (struct snmp_oid *)&oid) == -1) {
		ret = AGENTX_ERR_PARSE_ERROR;
		goto done;
	}

	*iter = ber_add_sequence(*iter);
	if (*varbind == NULL)
		*varbind = *iter;

	a = ber_add_oid(*iter, &oid);

	switch (vbhdr->type) {
	case AGENTX_NO_SUCH_OBJECT:
	case AGENTX_NO_SUCH_INSTANCE:
	case AGENTX_END_OF_MIB_VIEW:
	case AGENTX_NULL:
		a = ber_add_null(a);
		break;

	case AGENTX_IP_ADDRESS:
	case AGENTX_OPAQUE:
	case AGENTX_OCTET_STRING:
		str = snmp_agentx_read_octetstr(pdu, &slen);
		if (str == NULL) {
			ret = AGENTX_ERR_PARSE_ERROR;
			goto done;
		}
		a = ber_add_nstring(a, str, slen);
		break;

	case AGENTX_OBJECT_IDENTIFIER:
		if (snmp_agentx_read_oid(pdu,
		    (struct snmp_oid *)&oid) == -1) {
			ret = AGENTX_ERR_PARSE_ERROR;
			goto done;
		}
		a = ber_add_oid(a, &oid);
		break;

	case AGENTX_INTEGER:
	case AGENTX_COUNTER32:
	case AGENTX_GAUGE32:
	case AGENTX_TIME_TICKS:
		if (snmp_agentx_read_int(pdu, &d) == -1) {
			ret = AGENTX_ERR_PARSE_ERROR;
			goto done;
		}
		a = ber_add_integer(a, d);
		break;

	case AGENTX_COUNTER64:
		if (snmp_agentx_read_int64(pdu, &l) == -1) {
			ret = AGENTX_ERR_PARSE_ERROR;
			goto done;
		}
		a = ber_add_integer(a, l);
		break;

	default:
		log_debug("unknown data type '%i'", vbhdr->type);
		ret = AGENTX_ERR_PARSE_ERROR;
		goto done;
	}

	/* AgentX types correspond to BER types */
	switch (vbhdr->type) {
	case BER_TYPE_INTEGER:
	case BER_TYPE_BITSTRING:
	case BER_TYPE_OCTETSTRING:
	case BER_TYPE_NULL:
	case BER_TYPE_OBJECT:
		/* universal types */
		break;

	/* Convert AgentX error types to SNMP error types */
	case AGENTX_NO_SUCH_OBJECT:
		ber_set_header(a, BER_CLASS_CONTEXT, 0);
		break;
	case AGENTX_NO_SUCH_INSTANCE:
		ber_set_header(a, BER_CLASS_CONTEXT, 1);
		break;

	case AGENTX_COUNTER32:
		ber_set_header(a, BER_CLASS_APPLICATION, SNMP_COUNTER32);
		break;

	case AGENTX_GAUGE32:
		ber_set_header(a, BER_CLASS_APPLICATION, SNMP_GAUGE32);
		break;

	case AGENTX_COUNTER64:
		ber_set_header(a, BER_CLASS_APPLICATION, SNMP_COUNTER64);
		break;

	case AGENTX_IP_ADDRESS:
		/* application 0 implicit 4-byte octet string per SNMPv2-SMI */
		break;

	default:
		/* application-specific types */
		ber_set_header(a, BER_CLASS_APPLICATION, vbhdr->type);
		break;
	}
 done:
	return (ret);
}
Пример #2
0
/* ARGSUSED */
void
control_dispatch_agentx(int fd, short event, void *arg)
{
	struct ctl_conn			*c = arg;
	struct agentx_handle		*h = c->handle;
	struct agentx_pdu		*pdu;
	struct timeval			 tv;
	struct agentx_open_timeout	 to;
	struct ber_oid			 oid;
	struct agentx_close_request_data clhdr;
	int				 closing = 0;
	int				 evflags = 0;
	int				 timer = 0;
	int				 error = AGENTX_ERR_NONE;
	int				 idx = 0, vcpylen, dlen, uptime;
	char				*descr, *varcpy;

	varcpy = descr = NULL;
	if (h->timeout != 0)
		tv.tv_sec = h->timeout;
	else
		tv.tv_sec = AGENTX_DEFAULT_TIMEOUT;
	tv.tv_usec = 0;

	if (event & EV_TIMEOUT) {
		log_info("subagent session '%i' timed out after %i seconds",
		    h->sessionid, h->timeout);
		goto teardown;
	}

	if (event & EV_WRITE) {
		if (snmp_agentx_send(h, NULL) == -1) {
			if (errno != EAGAIN)
				goto teardown;

			/* short write */
			evflags |= EV_WRITE;
			timer = 1;
		}
	}

	if (event & EV_READ) {
		if ((pdu = snmp_agentx_recv(h)) == NULL) {
			if (h->error) {
				error = h->error;
				goto respond;
			}
			if (errno != EAGAIN)
				goto teardown;

			/* short read */
			timer = 1;
			goto done;
		}

		switch (pdu->hdr->type) {
		case AGENTX_OPEN:
			if (snmp_agentx_read_raw(pdu, &to, sizeof(to)) == -1 ||
			    snmp_agentx_read_oid(pdu,
			    (struct snmp_oid *)&oid) == -1 ||
			    (descr =
			    snmp_agentx_read_octetstr(pdu, &dlen)) == NULL) {
				error = AGENTX_ERR_PARSE_ERROR;
				break;
			}

			log_info("opening AgentX socket for '%.*s'",
			    dlen, descr);

			h->sessionid = pdu->hdr->sessionid =
			    agentx_sessionid++;
			if (to.timeout != 0)
				h->timeout = to.timeout;
			else
				h->timeout = AGENTX_DEFAULT_TIMEOUT;
			break;

		case AGENTX_CLOSE:
			if (snmp_agentx_read_raw(pdu,
			    &clhdr, sizeof(clhdr)) == -1) {
				error = AGENTX_ERR_PARSE_ERROR;
				break;
			}
			closing = 1;
			break;

		case AGENTX_NOTIFY:
			error = trap_agentx(h, pdu, &idx, &varcpy, &vcpylen);
			break;

		case AGENTX_PING:
			/* no processing, just an empty response */
			break;

		case AGENTX_REGISTER: {
			struct agentx_register_hdr	 rhdr;
			struct oidlist			 oids;
			struct oid			*miboid;
			uint32_t			 ubound = 0;

			TAILQ_INIT(&oids);

			if (snmp_agentx_read_raw(pdu,
			    &rhdr, sizeof(rhdr)) == -1 ||
			    snmp_agentx_read_oid(pdu,
			    (struct snmp_oid *)&oid) == -1) {
				error = AGENTX_ERR_PARSE_ERROR;
				break;
			}

			do {
				if ((miboid = calloc(1, sizeof(*miboid))) == NULL) {
					purge_registered_oids(&oids);
					error = AGENTX_ERR_PARSE_ERROR;
					goto dodone;
				}
				bcopy(&oid, &miboid->o_id, sizeof(oid));
				miboid->o_flags = OID_RD|OID_WR|OID_REGISTERED;
				miboid->o_session = c;
				if (smi_insert(miboid) == -1) {
					purge_registered_oids(&oids);
					error = AGENTX_ERR_DUPLICATE_REGISTRATION;
					goto dodone;
				}
				TAILQ_INSERT_TAIL(&oids, miboid, o_list);
			} while (++oid.bo_id[rhdr.subrange] <= ubound);

			while ((miboid = TAILQ_FIRST(&oids)) != NULL) {
				TAILQ_REMOVE(&oids, miboid, o_list);
				TAILQ_INSERT_TAIL(&c->oids, miboid, o_list);
			}
 dodone:
			break;
		}

		case AGENTX_UNREGISTER: {
			struct agentx_unregister_hdr	 uhdr;
			struct oid			*miboid;
			uint32_t			 ubound = 0;

			if (snmp_agentx_read_raw(pdu,
			    &uhdr, sizeof(uhdr)) == -1 ||
			    snmp_agentx_read_oid(pdu,
			    (struct snmp_oid *)&oid) == -1) {
				error = AGENTX_ERR_PARSE_ERROR;
				break;
			}

			do {
				if ((miboid = smi_find((struct oid *)&oid)) == NULL) {
					log_warnx("attempting to remove unregistered MIB");
					continue;
				}
				if (miboid->o_session != c) {
					log_warnx("attempting to remove MIB registered by other session");
					continue;
				}
				smi_delete(miboid);
			} while (++oid.bo_id[uhdr.subrange] <= ubound);
			break;
		}

		case AGENTX_RESPONSE: {
			struct snmp_message		*msg = pdu->request->cookie;
			struct agentx_response_data	 resp;
			struct agentx_varbind_hdr	 vbhdr;
			struct ber_element		**elm, **iter;

			if (snmp_agentx_read_response(pdu, &resp) == -1) {
				msg->sm_error = SNMP_ERROR_GENERR;
				goto dispatch;
			}

			switch (resp.error) {
			case AGENTX_ERR_NONE:
				break;

			/* per RFC, resp.error may be an SNMP error value */
			case SNMP_ERROR_TOOBIG:
			case SNMP_ERROR_NOSUCHNAME:
			case SNMP_ERROR_BADVALUE:
			case SNMP_ERROR_READONLY:
			case SNMP_ERROR_GENERR:
			case SNMP_ERROR_NOACCESS:
			case SNMP_ERROR_WRONGTYPE:
			case SNMP_ERROR_WRONGLENGTH:
			case SNMP_ERROR_WRONGENC:
			case SNMP_ERROR_WRONGVALUE:
			case SNMP_ERROR_NOCREATION:
			case SNMP_ERROR_INCONVALUE:
			case SNMP_ERROR_RESUNAVAIL:
			case SNMP_ERROR_COMMITFAILED:
			case SNMP_ERROR_UNDOFAILED:
			case SNMP_ERROR_AUTHERROR:
			case SNMP_ERROR_NOTWRITABLE:
			case SNMP_ERROR_INCONNAME:
				msg->sm_error = resp.error;
				msg->sm_errorindex = resp.index;
				break;

			case AGENTX_ERR_INDEX_WRONG_TYPE:
			case AGENTX_ERR_UNSUPPORTED_CONTEXT:
			case AGENTX_ERR_PARSE_ERROR:
			case AGENTX_ERR_REQUEST_DENIED:
			case AGENTX_ERR_PROCESSING_ERROR:
			default:
				msg->sm_error = SNMP_ERROR_GENERR;
				msg->sm_errorindex = resp.index;
				break;
			}

			iter = elm = &msg->sm_varbindresp;

			while (pdu->datalen > sizeof(struct agentx_hdr)) {
				if (snmp_agentx_read_raw(pdu, &vbhdr, sizeof(vbhdr)) == -1 ||
				    varbind_convert(pdu, &vbhdr, elm, iter)
				    != AGENTX_ERR_NONE) {
					msg->sm_error = SNMP_ERROR_GENERR;
					msg->sm_errorindex = msg->sm_i;
					goto dispatch;
				}
			}
 dispatch:
			snmpe_dispatchmsg(msg);
			break;
		}

		/* unimplemented, but parse and accept for now */
		case AGENTX_ADD_AGENT_CAPS:
		case AGENTX_REMOVE_AGENT_CAPS:
			break;

		/* unimplemented */
		case AGENTX_GET:
		case AGENTX_GET_NEXT:
		case AGENTX_GET_BULK:
		case AGENTX_TEST_SET:
		case AGENTX_COMMIT_SET:
		case AGENTX_UNDO_SET:
		case AGENTX_CLEANUP_SET:
		case AGENTX_INDEX_ALLOCATE:
		case AGENTX_INDEX_DEALLOCATE:
			error = AGENTX_ERR_REQUEST_DENIED;
			break;

		/* NB: by RFC, this should precede all other checks. */
		default:
			log_info("unknown AgentX type '%i'", pdu->hdr->type);
			error = AGENTX_ERR_PARSE_ERROR;
			break;
		}
 respond:
		if (pdu)
			snmp_agentx_pdu_free(pdu);

		uptime = smi_getticks();
		if ((pdu = snmp_agentx_response_pdu(uptime, error, idx)) == NULL) {
			log_debug("failed to generate response");
			free(varcpy);
			control_event_add(c, fd, EV_WRITE, NULL);	/* XXX -- EV_WRITE? */
			return;
		}

		if (varcpy) {
			snmp_agentx_raw(pdu, varcpy, vcpylen); /* XXX */
			free(varcpy);
		}
		snmp_agentx_send(h, pdu);

		/* Request processed, now write out response */
		evflags |= EV_WRITE;
	}

	if (closing)
		goto teardown;
 done:
	control_event_add(c, fd, evflags, timer ? &tv : NULL);
	return;

 teardown:
	log_debug("subagent session '%i' destroyed", h->sessionid);
	snmp_agentx_free(h);
	purge_registered_oids(&c->oids);
	free(varcpy);
	control_close(c, "agentx teardown", NULL);
}