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5 * Permission to use, copy, modify, and/or distribute this software for any
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50 * Permission to use, copy, modify, and distribute this software for any
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58 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
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60 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
61 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
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67 #if defined(LIBC_SCCS) && !defined(lint)
68 static const char sccsid[] = "@(#)res_send.c 8.1 (Berkeley) 6/4/93";
69 static const char rcsid[] = "$Id: res_send.c,v 1.22 2009/01/22 23:49:23 tbox Exp $";
70 #endif /* LIBC_SCCS and not lint */
71 #include <sys/cdefs.h>
72 __FBSDID("$FreeBSD$");
76 * Send query to name server and wait for reply.
79 #include "port_before.h"
81 #include "fd_setsize.h"
84 #include "namespace.h"
85 #include <sys/types.h>
86 #include <sys/param.h>
88 #include <sys/socket.h>
91 #include <netinet/in.h>
92 #include <arpa/nameser.h>
93 #include <arpa/inet.h>
104 #include <isc/eventlib.h>
106 #include "port_after.h"
109 #include <sys/event.h>
112 #ifdef HAVE_STROPTS_H
116 #endif /* USE_POLL */
119 #include "un-namespace.h"
121 /* Options. Leave them on. */
125 #include "res_debug.h"
126 #include "res_private.h"
128 #define EXT(res) ((res)->_u._ext)
130 #if !defined(USE_POLL) && !defined(USE_KQUEUE)
131 static const int highestFD = FD_SETSIZE - 1;
136 static int get_salen(const struct sockaddr *);
137 static struct sockaddr * get_nsaddr(res_state, size_t);
138 static int send_vc(res_state, const u_char *, int,
139 u_char *, int, int *, int);
140 static int send_dg(res_state,
145 u_char *, int, int *, int, int,
147 static void Aerror(const res_state, FILE *, const char *, int,
148 const struct sockaddr *, int);
149 static void Perror(const res_state, FILE *, const char *, int);
150 static int sock_eq(struct sockaddr *, struct sockaddr *);
151 #if defined(NEED_PSELECT) && !defined(USE_POLL) && !defined(USE_KQUEUE)
152 static int pselect(int, void *, void *, void *,
156 void res_pquery(const res_state, const u_char *, int, FILE *);
158 static const int niflags = NI_NUMERICHOST | NI_NUMERICSERV;
163 * looks up "ina" in _res.ns_addr_list[]
170 *\li paul vixie, 29may94
173 res_ourserver_p(const res_state statp, const struct sockaddr *sa) {
174 const struct sockaddr_in *inp, *srv;
175 const struct sockaddr_in6 *in6p, *srv6;
178 switch (sa->sa_family) {
180 inp = (const struct sockaddr_in *)sa;
181 for (ns = 0; ns < statp->nscount; ns++) {
182 srv = (struct sockaddr_in *)get_nsaddr(statp, ns);
183 if (srv->sin_family == inp->sin_family &&
184 srv->sin_port == inp->sin_port &&
185 (srv->sin_addr.s_addr == INADDR_ANY ||
186 srv->sin_addr.s_addr == inp->sin_addr.s_addr))
191 if (EXT(statp).ext == NULL)
193 in6p = (const struct sockaddr_in6 *)sa;
194 for (ns = 0; ns < statp->nscount; ns++) {
195 srv6 = (struct sockaddr_in6 *)get_nsaddr(statp, ns);
196 if (srv6->sin6_family == in6p->sin6_family &&
197 srv6->sin6_port == in6p->sin6_port &&
198 #ifdef HAVE_SIN6_SCOPE_ID
199 (srv6->sin6_scope_id == 0 ||
200 srv6->sin6_scope_id == in6p->sin6_scope_id) &&
202 (IN6_IS_ADDR_UNSPECIFIED(&srv6->sin6_addr) ||
203 IN6_ARE_ADDR_EQUAL(&srv6->sin6_addr, &in6p->sin6_addr)))
214 * look for (name,type,class) in the query section of packet (buf,eom)
217 *\li buf + HFIXEDSZ <= eom
220 *\li -1 : format error
225 *\li paul vixie, 29may94
228 res_nameinquery(const char *name, int type, int class,
229 const u_char *buf, const u_char *eom)
231 const u_char *cp = buf + HFIXEDSZ;
232 int qdcount = ntohs(((const HEADER*)buf)->qdcount);
234 while (qdcount-- > 0) {
235 char tname[MAXDNAME+1];
236 int n, ttype, tclass;
238 n = dn_expand(buf, eom, cp, tname, sizeof tname);
242 if (cp + 2 * INT16SZ > eom)
244 ttype = ns_get16(cp); cp += INT16SZ;
245 tclass = ns_get16(cp); cp += INT16SZ;
246 if (ttype == type && tclass == class &&
247 ns_samename(tname, name) == 1)
254 * is there a 1:1 mapping of (name,type,class)
255 * in (buf1,eom1) and (buf2,eom2)?
258 *\li -1 : format error
259 *\li 0 : not a 1:1 mapping
260 *\li >0 : is a 1:1 mapping
263 *\li paul vixie, 29may94
266 res_queriesmatch(const u_char *buf1, const u_char *eom1,
267 const u_char *buf2, const u_char *eom2)
269 const u_char *cp = buf1 + HFIXEDSZ;
270 int qdcount = ntohs(((const HEADER*)buf1)->qdcount);
272 if (buf1 + HFIXEDSZ > eom1 || buf2 + HFIXEDSZ > eom2)
276 * Only header section present in replies to
277 * dynamic update packets.
279 if ((((const HEADER *)buf1)->opcode == ns_o_update) &&
280 (((const HEADER *)buf2)->opcode == ns_o_update))
283 if (qdcount != ntohs(((const HEADER*)buf2)->qdcount))
285 while (qdcount-- > 0) {
286 char tname[MAXDNAME+1];
287 int n, ttype, tclass;
289 n = dn_expand(buf1, eom1, cp, tname, sizeof tname);
293 if (cp + 2 * INT16SZ > eom1)
295 ttype = ns_get16(cp); cp += INT16SZ;
296 tclass = ns_get16(cp); cp += INT16SZ;
297 if (!res_nameinquery(tname, ttype, tclass, buf2, eom2))
304 res_nsend(res_state statp,
305 const u_char *buf, int buflen, u_char *ans, int anssiz)
307 int gotsomewhere, terrno, tries, v_circuit, resplen, ns, n;
311 char abuf[NI_MAXHOST];
313 /* No name servers or res_init() failure */
314 if (statp->nscount == 0 || EXT(statp).ext == NULL) {
318 if (anssiz < HFIXEDSZ) {
322 DprintQ((statp->options & RES_DEBUG) || (statp->pfcode & RES_PRF_QUERY),
323 (stdout, ";; res_send()\n"), buf, buflen);
324 v_circuit = (statp->options & RES_USEVC) || buflen > PACKETSZ;
329 if ((kq = kqueue()) < 0) {
330 Perror(statp, stderr, "kqueue", errno);
336 * If the ns_addr_list in the resolver context has changed, then
337 * invalidate our cached copy and the associated timing data.
339 if (EXT(statp).nscount != 0) {
341 struct sockaddr_storage peer;
342 ISC_SOCKLEN_T peerlen;
344 if (EXT(statp).nscount != statp->nscount)
347 for (ns = 0; ns < statp->nscount; ns++) {
348 if (statp->nsaddr_list[ns].sin_family &&
349 !sock_eq((struct sockaddr *)&statp->nsaddr_list[ns],
350 (struct sockaddr *)&EXT(statp).ext->nsaddrs[ns])) {
355 if (EXT(statp).nssocks[ns] == -1)
357 peerlen = sizeof(peer);
358 if (_getpeername(EXT(statp).nssocks[ns],
359 (struct sockaddr *)&peer, &peerlen) < 0) {
363 if (!sock_eq((struct sockaddr *)&peer,
364 get_nsaddr(statp, ns))) {
371 EXT(statp).nscount = 0;
376 * Maybe initialize our private copy of the ns_addr_list.
378 if (EXT(statp).nscount == 0) {
379 for (ns = 0; ns < statp->nscount; ns++) {
380 EXT(statp).nstimes[ns] = RES_MAXTIME;
381 EXT(statp).nssocks[ns] = -1;
382 if (!statp->nsaddr_list[ns].sin_family)
384 EXT(statp).ext->nsaddrs[ns].sin =
385 statp->nsaddr_list[ns];
387 EXT(statp).nscount = statp->nscount;
391 * Some resolvers want to even out the load on their nameservers.
392 * Note that RES_BLAST overrides RES_ROTATE.
394 if ((statp->options & RES_ROTATE) != 0U &&
395 (statp->options & RES_BLAST) == 0U) {
396 union res_sockaddr_union inu;
397 struct sockaddr_in ina;
398 int lastns = statp->nscount - 1;
402 if (EXT(statp).ext != NULL)
403 inu = EXT(statp).ext->nsaddrs[0];
404 ina = statp->nsaddr_list[0];
405 fd = EXT(statp).nssocks[0];
406 nstime = EXT(statp).nstimes[0];
407 for (ns = 0; ns < lastns; ns++) {
408 if (EXT(statp).ext != NULL)
409 EXT(statp).ext->nsaddrs[ns] =
410 EXT(statp).ext->nsaddrs[ns + 1];
411 statp->nsaddr_list[ns] = statp->nsaddr_list[ns + 1];
412 EXT(statp).nssocks[ns] = EXT(statp).nssocks[ns + 1];
413 EXT(statp).nstimes[ns] = EXT(statp).nstimes[ns + 1];
415 if (EXT(statp).ext != NULL)
416 EXT(statp).ext->nsaddrs[lastns] = inu;
417 statp->nsaddr_list[lastns] = ina;
418 EXT(statp).nssocks[lastns] = fd;
419 EXT(statp).nstimes[lastns] = nstime;
423 * Send request, RETRY times, or until successful.
425 for (tries = 0; tries < statp->retry; tries++) {
426 for (ns = 0; ns < statp->nscount; ns++) {
427 struct sockaddr *nsap;
429 nsap = get_nsaddr(statp, ns);
430 nsaplen = get_salen(nsap);
431 statp->_flags &= ~RES_F_LASTMASK;
432 statp->_flags |= (ns << RES_F_LASTSHIFT);
435 int done = 0, loops = 0;
440 act = (*statp->qhook)(&nsap, &buf, &buflen,
441 ans, anssiz, &resplen);
455 /* give the hook another try */
456 if (++loops < 42) /*doug adams*/
467 Dprint(((statp->options & RES_DEBUG) &&
468 getnameinfo(nsap, nsaplen, abuf, sizeof(abuf),
469 NULL, 0, niflags) == 0),
470 (stdout, ";; Querying server (# %d) address = %s\n",
475 /* Use VC; at most one attempt per server. */
476 tries = statp->retry;
477 n = send_vc(statp, buf, buflen, ans, anssiz, &terrno,
490 buf, buflen, ans, anssiz, &terrno,
491 ns, tries, &v_circuit, &gotsomewhere);
501 Dprint((statp->options & RES_DEBUG) ||
502 ((statp->pfcode & RES_PRF_REPLY) &&
503 (statp->pfcode & RES_PRF_HEAD1)),
504 (stdout, ";; got answer:\n"));
506 DprintQ((statp->options & RES_DEBUG) ||
507 (statp->pfcode & RES_PRF_REPLY),
509 ans, (resplen > anssiz) ? anssiz : resplen);
512 * If we have temporarily opened a virtual circuit,
513 * or if we haven't been asked to keep a socket open,
516 if ((v_circuit && (statp->options & RES_USEVC) == 0U) ||
517 (statp->options & RES_STAYOPEN) == 0U) {
521 int done = 0, loops = 0;
526 act = (*statp->rhook)(nsap, buf, buflen,
527 ans, anssiz, &resplen);
537 /* give the hook another try */
538 if (++loops < 42) /*doug adams*/
562 errno = ECONNREFUSED; /*%< no nameservers found */
564 errno = ETIMEDOUT; /*%< no answer obtained */
580 const struct sockaddr *sa;
584 /* There are people do not set sa_len. Be forgiving to them. */
589 if (sa->sa_family == AF_INET)
590 return (sizeof(struct sockaddr_in));
591 else if (sa->sa_family == AF_INET6)
592 return (sizeof(struct sockaddr_in6));
594 return (0); /*%< unknown, die on connect */
598 * pick appropriate nsaddr_list for use. see res_init() for initialization.
600 static struct sockaddr *
606 if (!statp->nsaddr_list[n].sin_family && EXT(statp).ext) {
608 * - EXT(statp).ext->nsaddrs[n] holds an address that is larger
609 * than struct sockaddr, and
610 * - user code did not update statp->nsaddr_list[n].
612 return (struct sockaddr *)(void *)&EXT(statp).ext->nsaddrs[n];
615 * - user code updated statp->nsaddr_list[n], or
616 * - statp->nsaddr_list[n] has the same content as
617 * EXT(statp).ext->nsaddrs[n].
619 return (struct sockaddr *)(void *)&statp->nsaddr_list[n];
624 send_vc(res_state statp,
625 const u_char *buf, int buflen, u_char *ans, int anssiz,
628 const HEADER *hp = (const HEADER *) buf;
629 HEADER *anhp = (HEADER *) ans;
630 struct sockaddr *nsap;
632 int truncating, connreset, resplen, n;
641 nsap = get_nsaddr(statp, ns);
642 nsaplen = get_salen(nsap);
648 /* Are we still talking to whom we want to talk to? */
649 if (statp->_vcsock >= 0 && (statp->_flags & RES_F_VC) != 0) {
650 struct sockaddr_storage peer;
651 ISC_SOCKLEN_T size = sizeof peer;
653 if (_getpeername(statp->_vcsock,
654 (struct sockaddr *)&peer, &size) < 0 ||
655 !sock_eq((struct sockaddr *)&peer, nsap)) {
657 statp->_flags &= ~RES_F_VC;
661 if (statp->_vcsock < 0 || (statp->_flags & RES_F_VC) == 0) {
662 if (statp->_vcsock >= 0)
665 statp->_vcsock = _socket(nsap->sa_family, SOCK_STREAM |
667 #if !defined(USE_POLL) && !defined(USE_KQUEUE)
668 if (statp->_vcsock > highestFD) {
673 if (statp->_vcsock < 0) {
675 case EPROTONOSUPPORT:
680 Perror(statp, stderr, "socket(vc)", errno);
684 Perror(statp, stderr, "socket(vc)", errno);
690 * Disable generation of SIGPIPE when writing to a closed
691 * socket. Write should return -1 and set errno to EPIPE
694 * Push on even if setsockopt(SO_NOSIGPIPE) fails.
696 (void)_setsockopt(statp->_vcsock, SOL_SOCKET, SO_NOSIGPIPE, &on,
700 if (_connect(statp->_vcsock, nsap, nsaplen) < 0) {
702 Aerror(statp, stderr, "connect/vc", errno, nsap,
707 statp->_flags |= RES_F_VC;
711 * Send length & message
713 ns_put16((u_short)buflen, (u_char*)&len);
714 iov[0] = evConsIovec(&len, INT16SZ);
716 iov[1] = evConsIovec(tmp, buflen);
717 if (_writev(statp->_vcsock, iov, 2) != (INT16SZ + buflen)) {
719 Perror(statp, stderr, "write failed", errno);
724 * Receive length & response
729 while ((n = _read(statp->_vcsock, (char *)cp, (int)len)) > 0) {
736 Perror(statp, stderr, "read failed", errno);
739 * A long running process might get its TCP
740 * connection reset if the remote server was
741 * restarted. Requery the server instead of
742 * trying a new one. When there is only one
743 * server, this means that a query might work
744 * instead of failing. We only allow one reset
745 * per query to prevent looping.
747 if (*terrno == ECONNRESET && !connreset) {
755 resplen = ns_get16(ans);
756 if (resplen > anssiz) {
757 Dprint(statp->options & RES_DEBUG,
758 (stdout, ";; response truncated\n")
764 if (len < HFIXEDSZ) {
766 * Undersized message.
768 Dprint(statp->options & RES_DEBUG,
769 (stdout, ";; undersized: %d\n", len));
776 (n = _read(statp->_vcsock, (char *)cp, (int)len)) > 0) {
782 Perror(statp, stderr, "read(vc)", errno);
788 * Flush rest of answer so connection stays in synch.
791 len = resplen - anssiz;
795 n = _read(statp->_vcsock, junk,
796 (len > sizeof junk) ? sizeof junk : len);
804 * If the calling applicating has bailed out of
805 * a previous call and failed to arrange to have
806 * the circuit closed or the server has got
807 * itself confused, then drop the packet and
808 * wait for the correct one.
810 if (hp->id != anhp->id) {
811 DprintQ((statp->options & RES_DEBUG) ||
812 (statp->pfcode & RES_PRF_REPLY),
813 (stdout, ";; old answer (unexpected):\n"),
814 ans, (resplen > anssiz) ? anssiz: resplen);
819 * All is well, or the error is fatal. Signal that the
820 * next nameserver ought not be tried.
826 send_dg(res_state statp,
830 const u_char *buf, int buflen, u_char *ans,
831 int anssiz, int *terrno, int ns, int tries, int *v_circuit,
834 const HEADER *hp = (const HEADER *) buf;
835 HEADER *anhp = (HEADER *) ans;
836 const struct sockaddr *nsap;
838 struct timespec now, timeout, finish;
839 struct sockaddr_storage from;
840 ISC_SOCKLEN_T fromlen;
841 int resplen, seconds, n, s;
847 struct pollfd pollfd;
853 nsap = get_nsaddr(statp, ns);
854 nsaplen = get_salen(nsap);
855 if (EXT(statp).nssocks[ns] == -1) {
856 EXT(statp).nssocks[ns] = _socket(nsap->sa_family,
857 SOCK_DGRAM | SOCK_CLOEXEC, 0);
858 #if !defined(USE_POLL) && !defined(USE_KQUEUE)
859 if (EXT(statp).nssocks[ns] > highestFD) {
864 if (EXT(statp).nssocks[ns] < 0) {
866 case EPROTONOSUPPORT:
871 Perror(statp, stderr, "socket(dg)", errno);
875 Perror(statp, stderr, "socket(dg)", errno);
879 #ifndef CANNOT_CONNECT_DGRAM
881 * On a 4.3BSD+ machine (client and server,
882 * actually), sending to a nameserver datagram
883 * port with no nameserver will cause an
884 * ICMP port unreachable message to be returned.
885 * If our datagram socket is "connected" to the
886 * server, we get an ECONNREFUSED error on the next
887 * socket operation, and select returns if the
888 * error message is received. We can thus detect
889 * the absence of a nameserver without timing out.
891 * When the option "insecure1" is specified, we'd
892 * rather expect to see responses from an "unknown"
893 * address. In order to let the kernel accept such
894 * responses, do not connect the socket here.
895 * XXX: or do we need an explicit option to disable
898 if (!(statp->options & RES_INSECURE1) &&
899 _connect(EXT(statp).nssocks[ns], nsap, nsaplen) < 0) {
900 Aerror(statp, stderr, "connect(dg)", errno, nsap,
905 #endif /* !CANNOT_CONNECT_DGRAM */
906 Dprint(statp->options & RES_DEBUG,
907 (stdout, ";; new DG socket\n"))
909 s = EXT(statp).nssocks[ns];
910 #ifndef CANNOT_CONNECT_DGRAM
911 if (statp->options & RES_INSECURE1) {
913 (const char*)buf, buflen, 0, nsap, nsaplen) != buflen) {
914 Aerror(statp, stderr, "sendto", errno, nsap, nsaplen);
918 } else if (send(s, (const char*)buf, buflen, 0) != buflen) {
919 Perror(statp, stderr, "send", errno);
923 #else /* !CANNOT_CONNECT_DGRAM */
924 if (_sendto(s, (const char*)buf, buflen, 0, nsap, nsaplen) != buflen)
926 Aerror(statp, stderr, "sendto", errno, nsap, nsaplen);
930 #endif /* !CANNOT_CONNECT_DGRAM */
935 seconds = (statp->retrans << tries);
937 seconds /= statp->nscount;
941 timeout = evConsTime(seconds, 0);
942 finish = evAddTime(now, timeout);
948 if (evCmpTime(finish, now) > 0)
949 timeout = evSubTime(finish, now);
951 timeout = evConsTime(0, 0);
953 EV_SET(&kv, s, EVFILT_READ, EV_ADD | EV_ONESHOT, 0, 0, 0);
954 n = _kevent(kq, &kv, 1, &kv, 1, &timeout);
958 n = pselect(s + 1, &dsmask, NULL, NULL, &timeout, NULL);
961 timeout = evSubTime(finish, now);
962 if (timeout.tv_sec < 0)
963 timeout = evConsTime(0, 0);
964 polltimeout = 1000*timeout.tv_sec +
965 timeout.tv_nsec/1000000;
967 pollfd.events = POLLRDNORM;
968 n = poll(&pollfd, 1, polltimeout);
969 #endif /* USE_POLL */
972 Dprint(statp->options & RES_DEBUG, (stdout, ";; timeout\n"));
980 Perror(statp, stderr, "kevent", errno);
983 Perror(statp, stderr, "select", errno);
985 Perror(statp, stderr, "poll", errno);
986 #endif /* USE_POLL */
996 fromlen = sizeof(from);
997 resplen = _recvfrom(s, (char*)ans, anssiz,0,
998 (struct sockaddr *)&from, &fromlen);
1000 Perror(statp, stderr, "recvfrom", errno);
1005 if (resplen < HFIXEDSZ) {
1007 * Undersized message.
1009 Dprint(statp->options & RES_DEBUG,
1010 (stdout, ";; undersized: %d\n",
1016 if (hp->id != anhp->id) {
1018 * response from old query, ignore it.
1019 * XXX - potential security hazard could
1022 DprintQ((statp->options & RES_DEBUG) ||
1023 (statp->pfcode & RES_PRF_REPLY),
1024 (stdout, ";; old answer:\n"),
1025 ans, (resplen > anssiz) ? anssiz : resplen);
1028 if (!(statp->options & RES_INSECURE1) &&
1029 !res_ourserver_p(statp, (struct sockaddr *)&from)) {
1031 * response from wrong server? ignore it.
1032 * XXX - potential security hazard could
1035 DprintQ((statp->options & RES_DEBUG) ||
1036 (statp->pfcode & RES_PRF_REPLY),
1037 (stdout, ";; not our server:\n"),
1038 ans, (resplen > anssiz) ? anssiz : resplen);
1041 #ifdef RES_USE_EDNS0
1042 if (anhp->rcode == FORMERR && (statp->options & RES_USE_EDNS0) != 0U) {
1044 * Do not retry if the server do not understand EDNS0.
1045 * The case has to be captured here, as FORMERR packet do not
1046 * carry query section, hence res_queriesmatch() returns 0.
1048 DprintQ(statp->options & RES_DEBUG,
1049 (stdout, "server rejected query with EDNS0:\n"),
1050 ans, (resplen > anssiz) ? anssiz : resplen);
1051 /* record the error */
1052 statp->_flags |= RES_F_EDNS0ERR;
1057 if (!(statp->options & RES_INSECURE2) &&
1058 !res_queriesmatch(buf, buf + buflen,
1059 ans, ans + anssiz)) {
1061 * response contains wrong query? ignore it.
1062 * XXX - potential security hazard could
1065 DprintQ((statp->options & RES_DEBUG) ||
1066 (statp->pfcode & RES_PRF_REPLY),
1067 (stdout, ";; wrong query name:\n"),
1068 ans, (resplen > anssiz) ? anssiz : resplen);
1071 if (anhp->rcode == SERVFAIL ||
1072 anhp->rcode == NOTIMP ||
1073 anhp->rcode == REFUSED) {
1074 DprintQ(statp->options & RES_DEBUG,
1075 (stdout, "server rejected query:\n"),
1076 ans, (resplen > anssiz) ? anssiz : resplen);
1078 /* don't retry if called from dig */
1082 if (!(statp->options & RES_IGNTC) && anhp->tc) {
1084 * To get the rest of answer,
1085 * use TCP with same server.
1087 Dprint(statp->options & RES_DEBUG,
1088 (stdout, ";; truncated answer\n"));
1094 * All is well, or the error is fatal. Signal that the
1095 * next nameserver ought not be tried.
1101 Aerror(const res_state statp, FILE *file, const char *string, int error,
1102 const struct sockaddr *address, int alen)
1105 char hbuf[NI_MAXHOST];
1106 char sbuf[NI_MAXSERV];
1108 if ((statp->options & RES_DEBUG) != 0U) {
1109 if (getnameinfo(address, alen, hbuf, sizeof(hbuf),
1110 sbuf, sizeof(sbuf), niflags)) {
1111 strncpy(hbuf, "?", sizeof(hbuf) - 1);
1112 hbuf[sizeof(hbuf) - 1] = '\0';
1113 strncpy(sbuf, "?", sizeof(sbuf) - 1);
1114 sbuf[sizeof(sbuf) - 1] = '\0';
1116 fprintf(file, "res_send: %s ([%s].%s): %s\n",
1117 string, hbuf, sbuf, strerror(error));
1123 Perror(const res_state statp, FILE *file, const char *string, int error) {
1126 if ((statp->options & RES_DEBUG) != 0U)
1127 fprintf(file, "res_send: %s: %s\n",
1128 string, strerror(error));
1133 sock_eq(struct sockaddr *a, struct sockaddr *b) {
1134 struct sockaddr_in *a4, *b4;
1135 struct sockaddr_in6 *a6, *b6;
1137 if (a->sa_family != b->sa_family)
1139 switch (a->sa_family) {
1141 a4 = (struct sockaddr_in *)a;
1142 b4 = (struct sockaddr_in *)b;
1143 return a4->sin_port == b4->sin_port &&
1144 a4->sin_addr.s_addr == b4->sin_addr.s_addr;
1146 a6 = (struct sockaddr_in6 *)a;
1147 b6 = (struct sockaddr_in6 *)b;
1148 return a6->sin6_port == b6->sin6_port &&
1149 #ifdef HAVE_SIN6_SCOPE_ID
1150 a6->sin6_scope_id == b6->sin6_scope_id &&
1152 IN6_ARE_ADDR_EQUAL(&a6->sin6_addr, &b6->sin6_addr);
1158 #if defined(NEED_PSELECT) && !defined(USE_POLL) && !defined(USE_KQUEUE)
1159 /* XXX needs to move to the porting library. */
1161 pselect(int nfds, void *rfds, void *wfds, void *efds,
1162 struct timespec *tsp, const sigset_t *sigmask)
1164 struct timeval tv, *tvp;
1170 tv = evTimeVal(*tsp);
1174 sigprocmask(SIG_SETMASK, sigmask, &sigs);
1175 n = select(nfds, rfds, wfds, efds, tvp);
1177 sigprocmask(SIG_SETMASK, &sigs, NULL);
1179 *tsp = evTimeSpec(tv);