4 * Network implementation
5 * All network related functions are grouped here
7 * a Net::DNS like library for C
9 * (c) NLnet Labs, 2004-2006
11 * See the file LICENSE for the license
14 #include <ldns/config.h>
16 #include <ldns/ldns.h>
18 #ifdef HAVE_NETINET_IN_H
19 #include <netinet/in.h>
21 #ifdef HAVE_SYS_SOCKET_H
22 #include <sys/socket.h>
27 #ifdef HAVE_ARPA_INET_H
28 #include <arpa/inet.h>
35 ldns_send(ldns_pkt **result_packet, ldns_resolver *r, const ldns_pkt *query_pkt)
39 ldns_rdf *tsig_mac = NULL;
41 qb = ldns_buffer_new(LDNS_MIN_BUFLEN);
43 if (query_pkt && ldns_pkt_tsig(query_pkt)) {
44 tsig_mac = ldns_rr_rdf(ldns_pkt_tsig(query_pkt), 3);
48 ldns_pkt2buffer_wire(qb, query_pkt) != LDNS_STATUS_OK) {
49 result = LDNS_STATUS_ERR;
51 result = ldns_send_buffer(result_packet, r, qb, tsig_mac);
60 ldns_send_buffer(ldns_pkt **result, ldns_resolver *r, ldns_buffer *qb, ldns_rdf *tsig_mac)
64 struct sockaddr_storage *ns;
72 bool all_servers_rtt_inf;
75 uint8_t *reply_bytes = NULL;
76 size_t reply_size = 0;
77 ldns_status status, send_status;
81 status = LDNS_STATUS_OK;
82 rtt = ldns_resolver_rtt(r);
83 ns_array = ldns_resolver_nameservers(r);
87 all_servers_rtt_inf = true;
89 if (ldns_resolver_random(r)) {
90 ldns_resolver_nameservers_randomize(r);
93 /* loop through all defined nameservers */
94 for (i = 0; i < ldns_resolver_nameserver_count(r); i++) {
95 if (rtt[i] == LDNS_RESOLV_RTT_INF) {
96 /* not reachable nameserver! */
100 /* maybe verbosity setting?
101 printf("Sending to ");
102 ldns_rdf_print(stdout, ns_array[i]);
105 ns = ldns_rdf2native_sockaddr_storage(ns_array[i],
106 ldns_resolver_port(r), &ns_len);
108 if ((ns->ss_family == AF_INET) &&
109 (ldns_resolver_ip6(r) == LDNS_RESOLV_INET6)) {
114 if ((ns->ss_family == AF_INET6) &&
115 (ldns_resolver_ip6(r) == LDNS_RESOLV_INET)) {
120 all_servers_rtt_inf = false;
122 gettimeofday(&tv_s, NULL);
124 send_status = LDNS_STATUS_ERR;
126 /* reply_bytes implicitly handles our error */
127 if (1 == ldns_resolver_usevc(r)) {
128 for (retries = ldns_resolver_retry(r); retries > 0; retries--) {
130 ldns_tcp_send(&reply_bytes, qb, ns,
131 (socklen_t)ns_len, ldns_resolver_timeout(r),
133 if (send_status == LDNS_STATUS_OK) {
138 for (retries = ldns_resolver_retry(r); retries > 0; retries--) {
139 /* ldns_rdf_print(stdout, ns_array[i]); */
141 ldns_udp_send(&reply_bytes, qb, ns,
142 (socklen_t)ns_len, ldns_resolver_timeout(r),
145 if (send_status == LDNS_STATUS_OK) {
151 if (send_status != LDNS_STATUS_OK) {
152 ldns_resolver_set_nameserver_rtt(r, i, LDNS_RESOLV_RTT_INF);
153 status = send_status;
156 /* obey the fail directive */
158 /* the current nameserver seems to have a problem, blacklist it */
159 if (ldns_resolver_fail(r)) {
161 return LDNS_STATUS_ERR;
168 status = ldns_wire2pkt(&reply, reply_bytes, reply_size);
169 if (status != LDNS_STATUS_OK) {
170 LDNS_FREE(reply_bytes);
176 gettimeofday(&tv_e, NULL);
179 ldns_pkt_set_querytime(reply, (uint32_t)
180 ((tv_e.tv_sec - tv_s.tv_sec) * 1000) +
181 (tv_e.tv_usec - tv_s.tv_usec) / 1000);
182 ldns_pkt_set_answerfrom(reply, ns_array[i]);
183 ldns_pkt_set_timestamp(reply, tv_s);
184 ldns_pkt_set_size(reply, reply_size);
187 if (ldns_resolver_fail(r)) {
188 /* if fail is set bail out, after the first
194 /* wait retrans seconds... */
195 sleep((unsigned int) ldns_resolver_retrans(r));
198 if (all_servers_rtt_inf) {
199 LDNS_FREE(reply_bytes);
200 return LDNS_STATUS_RES_NO_NS;
203 if (tsig_mac && reply_bytes) {
204 if (!ldns_pkt_tsig_verify(reply,
207 ldns_resolver_tsig_keyname(r),
208 ldns_resolver_tsig_keydata(r), tsig_mac)) {
209 status = LDNS_STATUS_CRYPTO_TSIG_BOGUS;
214 #endif /* HAVE_SSL */
216 LDNS_FREE(reply_bytes);
224 /** best effort to set nonblocking */
226 ldns_sock_nonblock(int sockfd)
230 if((flag = fcntl(sockfd, F_GETFL)) != -1) {
232 if(fcntl(sockfd, F_SETFL, flag) == -1) {
233 /* ignore error, continue blockingly */
236 #elif defined(HAVE_IOCTLSOCKET)
237 unsigned long on = 1;
238 if(ioctlsocket(sockfd, FIONBIO, &on) != 0) {
239 /* ignore error, continue blockingly */
244 /** best effort to set blocking */
246 ldns_sock_block(int sockfd)
250 if((flag = fcntl(sockfd, F_GETFL)) != -1) {
252 if(fcntl(sockfd, F_SETFL, flag) == -1) {
253 /* ignore error, continue */
256 #elif defined(HAVE_IOCTLSOCKET)
257 unsigned long off = 0;
258 if(ioctlsocket(sockfd, FIONBIO, &off) != 0) {
259 /* ignore error, continue */
264 /** wait for a socket to become ready */
266 ldns_sock_wait(int sockfd, struct timeval timeout, int write)
271 FD_SET(FD_SET_T sockfd, &fds);
273 ret = select(sockfd+1, NULL, &fds, NULL, &timeout);
275 ret = select(sockfd+1, &fds, NULL, NULL, &timeout);
277 /* timeout expired */
286 ldns_udp_send(uint8_t **result, ldns_buffer *qbin, const struct sockaddr_storage *to,
287 socklen_t tolen, struct timeval timeout, size_t *answer_size)
292 sockfd = ldns_udp_bgsend(qbin, to, tolen, timeout);
295 return LDNS_STATUS_SOCKET_ERROR;
298 /* wait for an response*/
299 if(!ldns_sock_wait(sockfd, timeout, 0)) {
305 return LDNS_STATUS_NETWORK_ERR;
308 answer = ldns_udp_read_wire(sockfd, answer_size, NULL, NULL);
315 if (*answer_size == 0) {
317 return LDNS_STATUS_NETWORK_ERR;
321 return LDNS_STATUS_OK;
325 ldns_udp_bgsend(ldns_buffer *qbin, const struct sockaddr_storage *to, socklen_t tolen,
326 struct timeval timeout)
330 sockfd = ldns_udp_connect(to, timeout);
336 if (ldns_udp_send_query(qbin, sockfd, to, tolen) == 0) {
343 ldns_udp_connect(const struct sockaddr_storage *to, struct timeval ATTR_UNUSED(timeout))
347 if ((sockfd = socket((int)((struct sockaddr*)to)->sa_family, SOCK_DGRAM,
356 ldns_tcp_connect(const struct sockaddr_storage *to, socklen_t tolen,
357 struct timeval timeout)
361 if ((sockfd = socket((int)((struct sockaddr*)to)->sa_family, SOCK_STREAM,
362 IPPROTO_TCP)) == -1) {
366 /* perform nonblocking connect, to be able to wait with select() */
367 ldns_sock_nonblock(sockfd);
368 if (connect(sockfd, (struct sockaddr*)to, tolen) == -1) {
371 if(errno != EINPROGRESS) {
378 #else /* USE_WINSOCK */
379 if(WSAGetLastError() != WSAEINPROGRESS &&
380 WSAGetLastError() != WSAEWOULDBLOCK) {
385 /* error was only telling us that it would block */
388 /* wait(write) until connected or error */
391 socklen_t len = (socklen_t)sizeof(error);
393 if(!ldns_sock_wait(sockfd, timeout, 1)) {
402 /* check if there is a pending error for nonblocking connect */
403 if(getsockopt(sockfd, SOL_SOCKET, SO_ERROR, (void*)&error,
406 error = errno; /* on solaris errno is error */
408 error = WSAGetLastError();
412 #if defined(EINPROGRESS) && defined(EWOULDBLOCK)
413 if(error == EINPROGRESS || error == EWOULDBLOCK)
414 continue; /* try again */
416 else if(error != 0) {
418 /* error in errno for our user */
422 #else /* USE_WINSOCK */
423 if(error == WSAEINPROGRESS)
425 else if(error == WSAEWOULDBLOCK)
427 else if(error != 0) {
432 #endif /* USE_WINSOCK */
437 /* set the socket blocking again */
438 ldns_sock_block(sockfd);
444 ldns_tcp_send_query(ldns_buffer *qbin, int sockfd,
445 const struct sockaddr_storage *to, socklen_t tolen)
450 /* add length of packet */
451 sendbuf = LDNS_XMALLOC(uint8_t, ldns_buffer_position(qbin) + 2);
452 if(!sendbuf) return 0;
453 ldns_write_uint16(sendbuf, ldns_buffer_position(qbin));
454 memcpy(sendbuf + 2, ldns_buffer_export(qbin), ldns_buffer_position(qbin));
456 bytes = sendto(sockfd, (void*)sendbuf,
457 ldns_buffer_position(qbin) + 2, 0, (struct sockaddr *)to, tolen);
461 if (bytes == -1 || (size_t) bytes != ldns_buffer_position(qbin) + 2 ) {
467 /* don't wait for an answer */
469 ldns_udp_send_query(ldns_buffer *qbin, int sockfd, const struct sockaddr_storage *to,
474 bytes = sendto(sockfd, (void*)ldns_buffer_begin(qbin),
475 ldns_buffer_position(qbin), 0, (struct sockaddr *)to, tolen);
477 if (bytes == -1 || (size_t)bytes != ldns_buffer_position(qbin)) {
480 if ((size_t) bytes != ldns_buffer_position(qbin)) {
487 ldns_udp_read_wire(int sockfd, size_t *size, struct sockaddr_storage *from,
490 uint8_t *wire, *wireout;
493 wire = LDNS_XMALLOC(uint8_t, LDNS_MAX_PACKETLEN);
499 wire_size = recvfrom(sockfd, (void*)wire, LDNS_MAX_PACKETLEN, 0,
500 (struct sockaddr *)from, fromlen);
502 /* recvfrom can also return 0 */
503 if (wire_size == -1 || wire_size == 0) {
509 *size = (size_t)wire_size;
510 wireout = LDNS_XREALLOC(wire, uint8_t, (size_t)wire_size);
511 if(!wireout) LDNS_FREE(wire);
517 ldns_tcp_read_wire_timeout(int sockfd, size_t *size, struct timeval timeout)
521 ssize_t bytes = 0, rc = 0;
523 wire = LDNS_XMALLOC(uint8_t, 2);
530 if(!ldns_sock_wait(sockfd, timeout, 0)) {
535 rc = recv(sockfd, (void*) (wire + bytes),
536 (size_t) (2 - bytes), 0);
537 if (rc == -1 || rc == 0) {
545 wire_size = ldns_read_uint16(wire);
548 wire = LDNS_XMALLOC(uint8_t, wire_size);
551 while (bytes < (ssize_t) wire_size) {
552 if(!ldns_sock_wait(sockfd, timeout, 0)) {
557 rc = recv(sockfd, (void*) (wire + bytes),
558 (size_t) (wire_size - bytes), 0);
559 if (rc == -1 || rc == 0) {
567 *size = (size_t) bytes;
572 ldns_tcp_read_wire(int sockfd, size_t *size)
576 ssize_t bytes = 0, rc = 0;
578 wire = LDNS_XMALLOC(uint8_t, 2);
585 rc = recv(sockfd, (void*) (wire + bytes),
586 (size_t) (2 - bytes), 0);
587 if (rc == -1 || rc == 0) {
595 wire_size = ldns_read_uint16(wire);
598 wire = LDNS_XMALLOC(uint8_t, wire_size);
601 while (bytes < (ssize_t) wire_size) {
602 rc = recv(sockfd, (void*) (wire + bytes),
603 (size_t) (wire_size - bytes), 0);
604 if (rc == -1 || rc == 0) {
612 *size = (size_t) bytes;
616 /* keep in mind that in DNS tcp messages the first 2 bytes signal the
617 * amount data to expect
620 ldns_tcp_send(uint8_t **result, ldns_buffer *qbin, const struct sockaddr_storage *to,
621 socklen_t tolen, struct timeval timeout, size_t *answer_size)
626 sockfd = ldns_tcp_bgsend(qbin, to, tolen, timeout);
629 return LDNS_STATUS_ERR;
632 answer = ldns_tcp_read_wire_timeout(sockfd, answer_size, timeout);
639 if (*answer_size == 0) {
641 return LDNS_STATUS_NETWORK_ERR;
644 /* resize accordingly */
645 answer = (uint8_t*)LDNS_XREALLOC(answer, uint8_t *, (size_t)*answer_size);
647 return LDNS_STATUS_OK;
651 ldns_tcp_bgsend(ldns_buffer *qbin, const struct sockaddr_storage *to, socklen_t tolen,
652 struct timeval timeout)
656 sockfd = ldns_tcp_connect(to, tolen, timeout);
662 if (ldns_tcp_send_query(qbin, sockfd, to, tolen) == 0) {
669 /* code from rdata.c */
670 struct sockaddr_storage *
671 ldns_rdf2native_sockaddr_storage(const ldns_rdf *rd, uint16_t port, size_t *size)
673 struct sockaddr_storage *data;
674 struct sockaddr_in *data_in;
675 struct sockaddr_in6 *data_in6;
677 data = LDNS_MALLOC(struct sockaddr_storage);
681 /* zero the structure for portability */
682 memset(data, 0, sizeof(struct sockaddr_storage));
687 switch(ldns_rdf_get_type(rd)) {
688 case LDNS_RDF_TYPE_A:
689 data->ss_family = AF_INET;
690 data_in = (struct sockaddr_in*) data;
691 data_in->sin_port = (in_port_t)htons(port);
692 memcpy(&(data_in->sin_addr), ldns_rdf_data(rd), ldns_rdf_size(rd));
693 *size = sizeof(struct sockaddr_in);
695 case LDNS_RDF_TYPE_AAAA:
696 data->ss_family = AF_INET6;
697 data_in6 = (struct sockaddr_in6*) data;
698 data_in6->sin6_port = (in_port_t)htons(port);
699 memcpy(&data_in6->sin6_addr, ldns_rdf_data(rd), ldns_rdf_size(rd));
700 *size = sizeof(struct sockaddr_in6);
709 ldns_sockaddr_storage2rdf(struct sockaddr_storage *sock, uint16_t *port)
712 struct sockaddr_in *data_in;
713 struct sockaddr_in6 *data_in6;
715 switch(sock->ss_family) {
717 data_in = (struct sockaddr_in*)sock;
719 *port = ntohs((uint16_t)data_in->sin_port);
721 addr = ldns_rdf_new_frm_data(LDNS_RDF_TYPE_A,
722 LDNS_IP4ADDRLEN, &data_in->sin_addr);
725 data_in6 = (struct sockaddr_in6*)sock;
727 *port = ntohs((uint16_t)data_in6->sin6_port);
729 addr = ldns_rdf_new_frm_data(LDNS_RDF_TYPE_AAAA,
730 LDNS_IP6ADDRLEN, &data_in6->sin6_addr);
741 /* code from resolver.c */
743 ldns_axfr_start(ldns_resolver *resolver, ldns_rdf *domain, ldns_rr_class class)
746 ldns_buffer *query_wire;
748 struct sockaddr_storage *ns = NULL;
753 if (!resolver || ldns_resolver_nameserver_count(resolver) < 1) {
754 return LDNS_STATUS_ERR;
757 query = ldns_pkt_query_new(ldns_rdf_clone(domain), LDNS_RR_TYPE_AXFR, class, 0);
760 return LDNS_STATUS_ADDRESS_ERR;
762 /* For AXFR, we have to make the connection ourselves */
763 /* try all nameservers (which usually would mean v4 fallback if
764 * @hostname is used */
766 ns_i < ldns_resolver_nameserver_count(resolver) &&
767 resolver->_socket == 0;
769 ns = ldns_rdf2native_sockaddr_storage(
770 resolver->_nameservers[ns_i],
771 ldns_resolver_port(resolver), &ns_len);
773 resolver->_socket = ldns_tcp_connect(ns, (socklen_t)ns_len,
774 ldns_resolver_timeout(resolver));
777 if (resolver->_socket == 0) {
778 ldns_pkt_free(query);
780 return LDNS_STATUS_NETWORK_ERR;
784 if (ldns_resolver_tsig_keyname(resolver) && ldns_resolver_tsig_keydata(resolver)) {
785 status = ldns_pkt_tsig_sign(query,
786 ldns_resolver_tsig_keyname(resolver),
787 ldns_resolver_tsig_keydata(resolver),
788 300, ldns_resolver_tsig_algorithm(resolver), NULL);
789 if (status != LDNS_STATUS_OK) {
790 /* RoRi: to prevent problems on subsequent calls to ldns_axfr_start
791 we have to close the socket here! */
793 close(resolver->_socket);
795 closesocket(resolver->_socket);
797 resolver->_socket = 0;
799 return LDNS_STATUS_CRYPTO_TSIG_ERR;
802 #endif /* HAVE_SSL */
804 /* Convert the query to a buffer
807 query_wire = ldns_buffer_new(LDNS_MAX_PACKETLEN);
808 status = ldns_pkt2buffer_wire(query_wire, query);
809 if (status != LDNS_STATUS_OK) {
810 ldns_pkt_free(query);
811 ldns_buffer_free(query_wire);
814 /* RoRi: to prevent problems on subsequent calls to ldns_axfr_start
815 we have to close the socket here! */
817 close(resolver->_socket);
819 closesocket(resolver->_socket);
821 resolver->_socket = 0;
826 if (ldns_tcp_send_query(query_wire, resolver->_socket, ns,
827 (socklen_t)ns_len) == 0) {
828 ldns_pkt_free(query);
829 ldns_buffer_free(query_wire);
832 /* RoRi: to prevent problems on subsequent calls to ldns_axfr_start
833 we have to close the socket here! */
836 close(resolver->_socket);
838 closesocket(resolver->_socket);
840 resolver->_socket = 0;
842 return LDNS_STATUS_NETWORK_ERR;
845 ldns_pkt_free(query);
846 ldns_buffer_free(query_wire);
850 * The AXFR is done once the second SOA record is sent
852 resolver->_axfr_soa_count = 0;
853 return LDNS_STATUS_OK;