Exemple #1
0
static void
handle_tcp_reading(netio_type *netio,
		   netio_handler_type *handler,
		   netio_event_types_type event_types)
{
	struct tcp_handler_data *data
		= (struct tcp_handler_data *) handler->user_data;
	ssize_t received;

	if (event_types & NETIO_EVENT_TIMEOUT) {
		/* Connection timed out.  */
		cleanup_tcp_handler(netio, handler);
		return;
	}

	if (data->nsd->tcp_query_count > 0 &&
		data->query_count >= data->nsd->tcp_query_count) {
		/* No more queries allowed on this tcp connection.  */
		cleanup_tcp_handler(netio, handler);
		return;
	}

	assert(event_types & NETIO_EVENT_READ);

	if (data->bytes_transmitted == 0) {
		query_reset(data->query, TCP_MAX_MESSAGE_LEN, 1);
	}

	/*
	 * Check if we received the leading packet length bytes yet.
	 */
	if (data->bytes_transmitted < sizeof(uint16_t)) {
		received = read(handler->fd,
				(char *) &data->query->tcplen
				+ data->bytes_transmitted,
				sizeof(uint16_t) - data->bytes_transmitted);
		if (received == -1) {
			if (errno == EAGAIN || errno == EINTR) {
				/*
				 * Read would block, wait until more
				 * data is available.
				 */
				return;
			} else {
#ifdef ECONNRESET
				if (verbosity >= 2 || errno != ECONNRESET)
#endif /* ECONNRESET */
				log_msg(LOG_ERR, "failed reading from tcp: %s", strerror(errno));
				cleanup_tcp_handler(netio, handler);
				return;
			}
		} else if (received == 0) {
			/* EOF */
			cleanup_tcp_handler(netio, handler);
			return;
		}

		data->bytes_transmitted += received;
		if (data->bytes_transmitted < sizeof(uint16_t)) {
			/*
			 * Not done with the tcplen yet, wait for more
			 * data to become available.
			 */
			return;
		}

		assert(data->bytes_transmitted == sizeof(uint16_t));

		data->query->tcplen = ntohs(data->query->tcplen);

		/*
		 * Minimum query size is:
		 *
		 *     Size of the header (12)
		 *   + Root domain name   (1)
		 *   + Query class        (2)
		 *   + Query type         (2)
		 */
		if (data->query->tcplen < QHEADERSZ + 1 + sizeof(uint16_t) + sizeof(uint16_t)) {
			VERBOSITY(2, (LOG_WARNING, "packet too small, dropping tcp connection"));
			cleanup_tcp_handler(netio, handler);
			return;
		}

		if (data->query->tcplen > data->query->maxlen) {
			VERBOSITY(2, (LOG_WARNING, "insufficient tcp buffer, dropping connection"));
			cleanup_tcp_handler(netio, handler);
			return;
		}

		buffer_set_limit(data->query->packet, data->query->tcplen);
	}

	assert(buffer_remaining(data->query->packet) > 0);

	/* Read the (remaining) query data.  */
	received = read(handler->fd,
			buffer_current(data->query->packet),
			buffer_remaining(data->query->packet));
	if (received == -1) {
		if (errno == EAGAIN || errno == EINTR) {
			/*
			 * Read would block, wait until more data is
			 * available.
			 */
			return;
		} else {
#ifdef ECONNRESET
			if (verbosity >= 2 || errno != ECONNRESET)
#endif /* ECONNRESET */
			log_msg(LOG_ERR, "failed reading from tcp: %s", strerror(errno));
			cleanup_tcp_handler(netio, handler);
			return;
		}
	} else if (received == 0) {
		/* EOF */
		cleanup_tcp_handler(netio, handler);
		return;
	}

	data->bytes_transmitted += received;
	buffer_skip(data->query->packet, received);
	if (buffer_remaining(data->query->packet) > 0) {
		/*
		 * Message not yet complete, wait for more data to
		 * become available.
		 */
		return;
	}

	assert(buffer_position(data->query->packet) == data->query->tcplen);

	/* Account... */
#ifdef BIND8_STATS
# ifndef INET6
	STATUP(data->nsd, ctcp);
# else
	if (data->query->addr.ss_family == AF_INET) {
		STATUP(data->nsd, ctcp);
	} else if (data->query->addr.ss_family == AF_INET6) {
		STATUP(data->nsd, ctcp6);
	}
# endif
#endif /* BIND8_STATS */

	/* We have a complete query, process it.  */

	/* tcp-query-count: handle query counter ++ */
	data->query_count++;

	buffer_flip(data->query->packet);
	data->query_state = server_process_query(data->nsd, data->query);
	if (data->query_state == QUERY_DISCARDED) {
		/* Drop the packet and the entire connection... */
		STATUP(data->nsd, dropped);
#if defined(BIND8_STATS) && defined(USE_ZONE_STATS)
		if (data->query->zone) {
			ZTATUP(data->query->zone, dropped);
		}
#endif
		cleanup_tcp_handler(netio, handler);
		return;
	}

#ifdef BIND8_STATS
	if (RCODE(data->query->packet) == RCODE_OK
	    && !AA(data->query->packet))
	{
		STATUP(data->nsd, nona);
		ZTATUP(data->query->zone, nona);
	}

# ifdef USE_ZONE_STATS
#  ifndef INET6
	ZTATUP(data->query->zone, ctcp);
#  else
	if (data->query->addr.ss_family == AF_INET) {
		ZTATUP(data->query->zone, ctcp);
	} else if (data->query->addr.ss_family == AF_INET6) {
		ZTATUP(data->query->zone, ctcp6);
	}
#  endif
# endif /* USE_ZONE_STATS */

#endif /* BIND8_STATS */

	query_add_optional(data->query, data->nsd);

	/* Switch to the tcp write handler.  */
	buffer_flip(data->query->packet);
	data->query->tcplen = buffer_remaining(data->query->packet);
	data->bytes_transmitted = 0;

	handler->timeout->tv_sec = data->nsd->tcp_timeout;
	handler->timeout->tv_nsec = 0L;
	timespec_add(handler->timeout, netio_current_time(netio));

	handler->event_types = NETIO_EVENT_WRITE | NETIO_EVENT_TIMEOUT;
	handler->event_handler = handle_tcp_writing;
}
Exemple #2
0
query_state_type
query_axfr(struct nsd *nsd, struct query *query)
{
	domain_type *closest_match;
	domain_type *closest_encloser;
	int exact;
	int added;
	uint16_t total_added = 0;

	if (query->axfr_is_done)
		return QUERY_PROCESSED;

	if (query->maxlen > AXFR_MAX_MESSAGE_LEN)
		query->maxlen = AXFR_MAX_MESSAGE_LEN;

	assert(!query_overflow(query));
	/* only keep running values for most packets */
	query->tsig_prepare_it = 0;
	query->tsig_update_it = 1;
	if(query->tsig_sign_it) {
		/* prepare for next updates */
		query->tsig_prepare_it = 1;
		query->tsig_sign_it = 0;
	}

	if (query->axfr_zone == NULL) {
		domain_type* qdomain;
		/* Start AXFR.  */
		STATUP(nsd, raxfr);
		exact = namedb_lookup(nsd->db,
				      query->qname,
				      &closest_match,
				      &closest_encloser);

		qdomain = closest_encloser;
		query->axfr_zone = domain_find_zone(nsd->db, closest_encloser);

		if (!exact
		    || query->axfr_zone == NULL
		    || query->axfr_zone->apex != qdomain
		    || query->axfr_zone->soa_rrset == NULL)
		{
			/* No SOA no transfer */
			RCODE_SET(query->packet, RCODE_NOTAUTH);
			return QUERY_PROCESSED;
		}
		ZTATUP(nsd, query->axfr_zone, raxfr);

		query->axfr_current_domain = qdomain;
		query->axfr_current_rrset = NULL;
		query->axfr_current_rr = 0;
		if(query->tsig.status == TSIG_OK) {
			query->tsig_sign_it = 1; /* sign first packet in stream */
		}

		query_add_compression_domain(query, qdomain, QHEADERSZ);

		assert(query->axfr_zone->soa_rrset->rr_count == 1);
		added = packet_encode_rr(query,
					 query->axfr_zone->apex,
					 &query->axfr_zone->soa_rrset->rrs[0],
					 query->axfr_zone->soa_rrset->rrs[0].ttl);
		if (!added) {
			/* XXX: This should never happen... generate error code? */
			abort();
		}
		++total_added;
	} else {
		/*
		 * Query name and EDNS need not be repeated after the
		 * first response packet.
		 */
		query->edns.status = EDNS_NOT_PRESENT;
		buffer_set_limit(query->packet, QHEADERSZ);
		QDCOUNT_SET(query->packet, 0);
		query_prepare_response(query);
	}

	/* Add zone RRs until answer is full.  */
	while (query->axfr_current_domain != NULL &&
			domain_is_subdomain(query->axfr_current_domain,
					    query->axfr_zone->apex))
	{
		if (!query->axfr_current_rrset) {
			query->axfr_current_rrset = domain_find_any_rrset(
				query->axfr_current_domain,
				query->axfr_zone);
			query->axfr_current_rr = 0;
		}
		while (query->axfr_current_rrset) {
			if (query->axfr_current_rrset != query->axfr_zone->soa_rrset
			    && query->axfr_current_rrset->zone == query->axfr_zone)
			{
				while (query->axfr_current_rr < query->axfr_current_rrset->rr_count) {
					added = packet_encode_rr(
						query,
						query->axfr_current_domain,
						&query->axfr_current_rrset->rrs[query->axfr_current_rr],
						query->axfr_current_rrset->rrs[query->axfr_current_rr].ttl);
					if (!added)
						goto return_answer;
					++total_added;
					++query->axfr_current_rr;
				}
			}

			query->axfr_current_rrset = query->axfr_current_rrset->next;
			query->axfr_current_rr = 0;
		}
		assert(query->axfr_current_domain);
		query->axfr_current_domain
			= domain_next(query->axfr_current_domain);
	}

	/* Add terminating SOA RR.  */
	assert(query->axfr_zone->soa_rrset->rr_count == 1);
	added = packet_encode_rr(query,
				 query->axfr_zone->apex,
				 &query->axfr_zone->soa_rrset->rrs[0],
				 query->axfr_zone->soa_rrset->rrs[0].ttl);
	if (added) {
		++total_added;
		query->tsig_sign_it = 1; /* sign last packet */
		query->axfr_is_done = 1;
	}

return_answer:
	AA_SET(query->packet);
	ANCOUNT_SET(query->packet, total_added);
	NSCOUNT_SET(query->packet, 0);
	ARCOUNT_SET(query->packet, 0);

	/* check if it needs tsig signatures */
	if(query->tsig.status == TSIG_OK) {
		if(query->tsig.updates_since_last_prepare >= AXFR_TSIG_SIGN_EVERY_NTH) {
			query->tsig_sign_it = 1;
		}
	}
	query_clear_compression_tables(query);
	return QUERY_IN_AXFR;
}
Exemple #3
0
static void
handle_udp(netio_type *ATTR_UNUSED(netio),
	   netio_handler_type *handler,
	   netio_event_types_type event_types)
{
	struct udp_handler_data *data
		= (struct udp_handler_data *) handler->user_data;
	int received, sent;
	struct query *q = data->query;

	if (!(event_types & NETIO_EVENT_READ)) {
		return;
	}

	/* Account... */
#ifdef BIND8_STATS
	if (data->socket->addr->ai_family == AF_INET) {
		STATUP(data->nsd, qudp);
	} else if (data->socket->addr->ai_family == AF_INET6) {
		STATUP(data->nsd, qudp6);
	}
#endif

	/* Initialize the query... */
	query_reset(q, UDP_MAX_MESSAGE_LEN, 0);

	received = recvfrom(handler->fd,
			    buffer_begin(q->packet),
			    buffer_remaining(q->packet),
			    0,
			    (struct sockaddr *)&q->addr,
			    &q->addrlen);
	if (received == -1) {
		if (errno != EAGAIN && errno != EINTR) {
			log_msg(LOG_ERR, "recvfrom failed: %s", strerror(errno));
			STATUP(data->nsd, rxerr);
			/* No zone statup */
		}
	} else {
		buffer_skip(q->packet, received);
		buffer_flip(q->packet);

		/* Process and answer the query... */
		if (server_process_query(data->nsd, q) != QUERY_DISCARDED) {
#ifdef BIND8_STATS
			if (RCODE(q->packet) == RCODE_OK && !AA(q->packet)) {
				STATUP(data->nsd, nona);
				ZTATUP(q->zone, nona);
			}

# ifdef USE_ZONE_STATS
			if (data->socket->addr->ai_family == AF_INET) {
				ZTATUP(q->zone, qudp);
			} else if (data->socket->addr->ai_family == AF_INET6) {
				ZTATUP(q->zone, qudp6);
			}
# endif
#endif

			/* Add EDNS0 and TSIG info if necessary.  */
			query_add_optional(q, data->nsd);

			buffer_flip(q->packet);

			sent = sendto(handler->fd,
				      buffer_begin(q->packet),
				      buffer_remaining(q->packet),
				      0,
				      (struct sockaddr *) &q->addr,
				      q->addrlen);
			if (sent == -1) {
				log_msg(LOG_ERR, "sendto failed: %s", strerror(errno));
				STATUP(data->nsd, txerr);
				ZTATUP(q->zone, txerr);
			} else if ((size_t) sent != buffer_remaining(q->packet)) {
				log_msg(LOG_ERR, "sent %d in place of %d bytes", sent, (int) buffer_remaining(q->packet));
#ifdef BIND8_STATS
			} else {
				/* Account the rcode & TC... */
				STATUP2(data->nsd, rcode, RCODE(q->packet));
				ZTATUP2(q->zone, rcode, RCODE(q->packet));
				if (TC(q->packet)) {
					STATUP(data->nsd, truncated);
					ZTATUP(q->zone, truncated);
				}
#endif /* BIND8_STATS */
			}
#ifdef BIND8_STATS
		} else {
			STATUP(data->nsd, dropped);
# ifdef USE_ZONE_STATS
			if (q->zone) {
				ZTATUP(q->zone, dropped);
			}
# endif
#endif
		}
	}
}