2 * SPDX-License-Identifier: (ISC AND BSD-3-Clause)
4 * Portions Copyright (C) 2004-2009 Internet Systems Consortium, Inc. ("ISC")
5 * Portions Copyright (C) 1996-2003 Internet Software Consortium.
7 * Permission to use, copy, modify, and/or distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
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15 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
16 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
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21 * Copyright (c) 1985, 1989, 1993
22 * The Regents of the University of California. All rights reserved.
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52 * Permission to use, copy, modify, and distribute this software for any
53 * purpose with or without fee is hereby granted, provided that the above
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60 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
61 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
62 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
63 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
64 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
65 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
69 #if defined(LIBC_SCCS) && !defined(lint)
70 static const char sccsid[] = "@(#)res_send.c 8.1 (Berkeley) 6/4/93";
71 static const char rcsid[] = "$Id: res_send.c,v 1.22 2009/01/22 23:49:23 tbox Exp $";
72 #endif /* LIBC_SCCS and not lint */
73 #include <sys/cdefs.h>
74 __FBSDID("$FreeBSD$");
78 * Send query to name server and wait for reply.
81 #include "port_before.h"
82 #if !defined(USE_KQUEUE) && !defined(USE_POLL)
83 #include "fd_setsize.h"
86 #include "namespace.h"
87 #include <sys/param.h>
89 #include <sys/socket.h>
92 #include <netinet/in.h>
93 #include <arpa/nameser.h>
94 #include <arpa/inet.h>
105 #include <isc/eventlib.h>
107 #include "port_after.h"
110 #include <sys/event.h>
113 #ifdef HAVE_STROPTS_H
117 #endif /* USE_POLL */
120 #include "un-namespace.h"
122 /* Options. Leave them on. */
126 #include "res_debug.h"
127 #include "res_private.h"
129 #define EXT(res) ((res)->_u._ext)
131 #if !defined(USE_POLL) && !defined(USE_KQUEUE)
132 static const int highestFD = FD_SETSIZE - 1;
137 static int get_salen(const struct sockaddr *);
138 static struct sockaddr * get_nsaddr(res_state, size_t);
139 static int send_vc(res_state, const u_char *, int,
140 u_char *, int, int *, int);
141 static int send_dg(res_state,
146 u_char *, int, int *, int, int,
148 static void Aerror(const res_state, FILE *, const char *, int,
149 const struct sockaddr *, int);
150 static void Perror(const res_state, FILE *, const char *, int);
151 static int sock_eq(struct sockaddr *, struct sockaddr *);
152 #if defined(NEED_PSELECT) && !defined(USE_POLL) && !defined(USE_KQUEUE)
153 static int pselect(int, void *, void *, void *,
157 void res_pquery(const res_state, const u_char *, int, FILE *);
159 static const int niflags = NI_NUMERICHOST | NI_NUMERICSERV;
164 * looks up "ina" in _res.ns_addr_list[]
171 *\li paul vixie, 29may94
174 res_ourserver_p(const res_state statp, const struct sockaddr *sa) {
175 const struct sockaddr_in *inp, *srv;
176 const struct sockaddr_in6 *in6p, *srv6;
179 switch (sa->sa_family) {
181 inp = (const struct sockaddr_in *)sa;
182 for (ns = 0; ns < statp->nscount; ns++) {
183 srv = (struct sockaddr_in *)get_nsaddr(statp, ns);
184 if (srv->sin_family == inp->sin_family &&
185 srv->sin_port == inp->sin_port &&
186 (srv->sin_addr.s_addr == INADDR_ANY ||
187 srv->sin_addr.s_addr == inp->sin_addr.s_addr))
192 if (EXT(statp).ext == NULL)
194 in6p = (const struct sockaddr_in6 *)sa;
195 for (ns = 0; ns < statp->nscount; ns++) {
196 srv6 = (struct sockaddr_in6 *)get_nsaddr(statp, ns);
197 if (srv6->sin6_family == in6p->sin6_family &&
198 srv6->sin6_port == in6p->sin6_port &&
199 #ifdef HAVE_SIN6_SCOPE_ID
200 (srv6->sin6_scope_id == 0 ||
201 srv6->sin6_scope_id == in6p->sin6_scope_id) &&
203 (IN6_IS_ADDR_UNSPECIFIED(&srv6->sin6_addr) ||
204 IN6_ARE_ADDR_EQUAL(&srv6->sin6_addr, &in6p->sin6_addr)))
215 * look for (name,type,class) in the query section of packet (buf,eom)
218 *\li buf + HFIXEDSZ <= eom
221 *\li -1 : format error
226 *\li paul vixie, 29may94
229 res_nameinquery(const char *name, int type, int class,
230 const u_char *buf, const u_char *eom)
232 const u_char *cp = buf + HFIXEDSZ;
233 int qdcount = ntohs(((const HEADER*)buf)->qdcount);
235 while (qdcount-- > 0) {
236 char tname[MAXDNAME+1];
237 int n, ttype, tclass;
239 n = dn_expand(buf, eom, cp, tname, sizeof tname);
243 if (cp + 2 * INT16SZ > eom)
245 ttype = ns_get16(cp); cp += INT16SZ;
246 tclass = ns_get16(cp); cp += INT16SZ;
247 if (ttype == type && tclass == class &&
248 ns_samename(tname, name) == 1)
255 * is there a 1:1 mapping of (name,type,class)
256 * in (buf1,eom1) and (buf2,eom2)?
259 *\li -1 : format error
260 *\li 0 : not a 1:1 mapping
261 *\li >0 : is a 1:1 mapping
264 *\li paul vixie, 29may94
267 res_queriesmatch(const u_char *buf1, const u_char *eom1,
268 const u_char *buf2, const u_char *eom2)
270 const u_char *cp = buf1 + HFIXEDSZ;
271 int qdcount = ntohs(((const HEADER*)buf1)->qdcount);
273 if (buf1 + HFIXEDSZ > eom1 || buf2 + HFIXEDSZ > eom2)
277 * Only header section present in replies to
278 * dynamic update packets.
280 if ((((const HEADER *)buf1)->opcode == ns_o_update) &&
281 (((const HEADER *)buf2)->opcode == ns_o_update))
284 if (qdcount != ntohs(((const HEADER*)buf2)->qdcount))
286 while (qdcount-- > 0) {
287 char tname[MAXDNAME+1];
288 int n, ttype, tclass;
290 n = dn_expand(buf1, eom1, cp, tname, sizeof tname);
294 if (cp + 2 * INT16SZ > eom1)
296 ttype = ns_get16(cp); cp += INT16SZ;
297 tclass = ns_get16(cp); cp += INT16SZ;
298 if (!res_nameinquery(tname, ttype, tclass, buf2, eom2))
305 res_nsend(res_state statp,
306 const u_char *buf, int buflen, u_char *ans, int anssiz)
308 int gotsomewhere, terrno, tries, v_circuit, resplen, ns, n;
312 char abuf[NI_MAXHOST];
314 /* No name servers or res_init() failure */
315 if (statp->nscount == 0 || EXT(statp).ext == NULL) {
319 if (anssiz < HFIXEDSZ) {
323 DprintQ((statp->options & RES_DEBUG) || (statp->pfcode & RES_PRF_QUERY),
324 (stdout, ";; res_send()\n"), buf, buflen);
325 v_circuit = (statp->options & RES_USEVC) || buflen > PACKETSZ;
330 if ((kq = kqueue()) < 0) {
331 Perror(statp, stderr, "kqueue", errno);
337 * If the ns_addr_list in the resolver context has changed, then
338 * invalidate our cached copy and the associated timing data.
340 if (EXT(statp).nscount != 0) {
342 struct sockaddr_storage peer;
343 ISC_SOCKLEN_T peerlen;
345 if (EXT(statp).nscount != statp->nscount)
348 for (ns = 0; ns < statp->nscount; ns++) {
349 if (statp->nsaddr_list[ns].sin_family &&
350 !sock_eq((struct sockaddr *)&statp->nsaddr_list[ns],
351 (struct sockaddr *)&EXT(statp).ext->nsaddrs[ns])) {
356 if (EXT(statp).nssocks[ns] == -1)
358 peerlen = sizeof(peer);
359 if (_getpeername(EXT(statp).nssocks[ns],
360 (struct sockaddr *)&peer, &peerlen) < 0) {
364 if (!sock_eq((struct sockaddr *)&peer,
365 get_nsaddr(statp, ns))) {
372 EXT(statp).nscount = 0;
377 * Maybe initialize our private copy of the ns_addr_list.
379 if (EXT(statp).nscount == 0) {
380 for (ns = 0; ns < statp->nscount; ns++) {
381 EXT(statp).nstimes[ns] = RES_MAXTIME;
382 EXT(statp).nssocks[ns] = -1;
383 if (!statp->nsaddr_list[ns].sin_family)
385 EXT(statp).ext->nsaddrs[ns].sin =
386 statp->nsaddr_list[ns];
388 EXT(statp).nscount = statp->nscount;
392 * Some resolvers want to even out the load on their nameservers.
393 * Note that RES_BLAST overrides RES_ROTATE.
395 if ((statp->options & RES_ROTATE) != 0U &&
396 (statp->options & RES_BLAST) == 0U) {
397 union res_sockaddr_union inu;
398 struct sockaddr_in ina;
399 int lastns = statp->nscount - 1;
403 if (EXT(statp).ext != NULL)
404 inu = EXT(statp).ext->nsaddrs[0];
405 ina = statp->nsaddr_list[0];
406 fd = EXT(statp).nssocks[0];
407 nstime = EXT(statp).nstimes[0];
408 for (ns = 0; ns < lastns; ns++) {
409 if (EXT(statp).ext != NULL)
410 EXT(statp).ext->nsaddrs[ns] =
411 EXT(statp).ext->nsaddrs[ns + 1];
412 statp->nsaddr_list[ns] = statp->nsaddr_list[ns + 1];
413 EXT(statp).nssocks[ns] = EXT(statp).nssocks[ns + 1];
414 EXT(statp).nstimes[ns] = EXT(statp).nstimes[ns + 1];
416 if (EXT(statp).ext != NULL)
417 EXT(statp).ext->nsaddrs[lastns] = inu;
418 statp->nsaddr_list[lastns] = ina;
419 EXT(statp).nssocks[lastns] = fd;
420 EXT(statp).nstimes[lastns] = nstime;
424 * Send request, RETRY times, or until successful.
426 for (tries = 0; tries < statp->retry; tries++) {
427 for (ns = 0; ns < statp->nscount; ns++) {
428 struct sockaddr *nsap;
430 nsap = get_nsaddr(statp, ns);
431 nsaplen = get_salen(nsap);
432 statp->_flags &= ~RES_F_LASTMASK;
433 statp->_flags |= (ns << RES_F_LASTSHIFT);
436 int done = 0, loops = 0;
441 act = (*statp->qhook)(&nsap, &buf, &buflen,
442 ans, anssiz, &resplen);
456 /* give the hook another try */
457 if (++loops < 42) /*doug adams*/
468 Dprint(((statp->options & RES_DEBUG) &&
469 getnameinfo(nsap, nsaplen, abuf, sizeof(abuf),
470 NULL, 0, niflags) == 0),
471 (stdout, ";; Querying server (# %d) address = %s\n",
476 /* Use VC; at most one attempt per server. */
477 tries = statp->retry;
478 n = send_vc(statp, buf, buflen, ans, anssiz, &terrno,
491 buf, buflen, ans, anssiz, &terrno,
492 ns, tries, &v_circuit, &gotsomewhere);
502 Dprint((statp->options & RES_DEBUG) ||
503 ((statp->pfcode & RES_PRF_REPLY) &&
504 (statp->pfcode & RES_PRF_HEAD1)),
505 (stdout, ";; got answer:\n"));
507 DprintQ((statp->options & RES_DEBUG) ||
508 (statp->pfcode & RES_PRF_REPLY),
510 ans, (resplen > anssiz) ? anssiz : resplen);
513 * If we have temporarily opened a virtual circuit,
514 * or if we haven't been asked to keep a socket open,
517 if ((v_circuit && (statp->options & RES_USEVC) == 0U) ||
518 (statp->options & RES_STAYOPEN) == 0U) {
522 int done = 0, loops = 0;
527 act = (*statp->rhook)(nsap, buf, buflen,
528 ans, anssiz, &resplen);
538 /* give the hook another try */
539 if (++loops < 42) /*doug adams*/
563 errno = ECONNREFUSED; /*%< no nameservers found */
565 errno = ETIMEDOUT; /*%< no answer obtained */
580 get_salen(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 *
601 get_nsaddr(res_state statp, size_t n)
604 if (!statp->nsaddr_list[n].sin_family && EXT(statp).ext) {
606 * - EXT(statp).ext->nsaddrs[n] holds an address that is larger
607 * than struct sockaddr, and
608 * - user code did not update statp->nsaddr_list[n].
610 return (struct sockaddr *)(void *)&EXT(statp).ext->nsaddrs[n];
613 * - user code updated statp->nsaddr_list[n], or
614 * - statp->nsaddr_list[n] has the same content as
615 * EXT(statp).ext->nsaddrs[n].
617 return (struct sockaddr *)(void *)&statp->nsaddr_list[n];
622 send_vc(res_state statp,
623 const u_char *buf, int buflen, u_char *ans, int anssiz,
626 const HEADER *hp = (const HEADER *) buf;
627 HEADER *anhp = (HEADER *) ans;
628 struct sockaddr *nsap;
630 int truncating, connreset, resplen, n;
639 nsap = get_nsaddr(statp, ns);
640 nsaplen = get_salen(nsap);
646 /* Are we still talking to whom we want to talk to? */
647 if (statp->_vcsock >= 0 && (statp->_flags & RES_F_VC) != 0) {
648 struct sockaddr_storage peer;
649 ISC_SOCKLEN_T size = sizeof peer;
651 if (_getpeername(statp->_vcsock,
652 (struct sockaddr *)&peer, &size) < 0 ||
653 !sock_eq((struct sockaddr *)&peer, nsap)) {
655 statp->_flags &= ~RES_F_VC;
659 if (statp->_vcsock < 0 || (statp->_flags & RES_F_VC) == 0) {
660 if (statp->_vcsock >= 0)
663 statp->_vcsock = _socket(nsap->sa_family, SOCK_STREAM |
665 #if !defined(USE_POLL) && !defined(USE_KQUEUE)
666 if (statp->_vcsock > highestFD) {
671 if (statp->_vcsock < 0) {
673 case EPROTONOSUPPORT:
678 Perror(statp, stderr, "socket(vc)", errno);
682 Perror(statp, stderr, "socket(vc)", errno);
688 * Disable generation of SIGPIPE when writing to a closed
689 * socket. Write should return -1 and set errno to EPIPE
692 * Push on even if setsockopt(SO_NOSIGPIPE) fails.
694 (void)_setsockopt(statp->_vcsock, SOL_SOCKET, SO_NOSIGPIPE, &on,
698 if (_connect(statp->_vcsock, nsap, nsaplen) < 0) {
700 Aerror(statp, stderr, "connect/vc", errno, nsap,
705 statp->_flags |= RES_F_VC;
709 * Send length & message
711 ns_put16((u_short)buflen, (u_char*)&len);
712 iov[0] = evConsIovec(&len, INT16SZ);
714 iov[1] = evConsIovec(tmp, buflen);
715 if (_writev(statp->_vcsock, iov, 2) != (INT16SZ + buflen)) {
717 Perror(statp, stderr, "write failed", errno);
722 * Receive length & response
727 while ((n = _read(statp->_vcsock, (char *)cp, (int)len)) > 0) {
734 Perror(statp, stderr, "read failed", errno);
737 * A long running process might get its TCP
738 * connection reset if the remote server was
739 * restarted. Requery the server instead of
740 * trying a new one. When there is only one
741 * server, this means that a query might work
742 * instead of failing. We only allow one reset
743 * per query to prevent looping.
745 if (*terrno == ECONNRESET && !connreset) {
753 resplen = ns_get16(ans);
754 if (resplen > anssiz) {
755 Dprint(statp->options & RES_DEBUG,
756 (stdout, ";; response truncated\n")
762 if (len < HFIXEDSZ) {
764 * Undersized message.
766 Dprint(statp->options & RES_DEBUG,
767 (stdout, ";; undersized: %d\n", len));
774 (n = _read(statp->_vcsock, (char *)cp, (int)len)) > 0) {
780 Perror(statp, stderr, "read(vc)", errno);
786 * Flush rest of answer so connection stays in synch.
789 len = resplen - anssiz;
793 n = _read(statp->_vcsock, junk,
794 (len > sizeof junk) ? sizeof junk : len);
802 * If the calling applicating has bailed out of
803 * a previous call and failed to arrange to have
804 * the circuit closed or the server has got
805 * itself confused, then drop the packet and
806 * wait for the correct one.
808 if (hp->id != anhp->id) {
809 DprintQ((statp->options & RES_DEBUG) ||
810 (statp->pfcode & RES_PRF_REPLY),
811 (stdout, ";; old answer (unexpected):\n"),
812 ans, (resplen > anssiz) ? anssiz: resplen);
817 * All is well, or the error is fatal. Signal that the
818 * next nameserver ought not be tried.
824 send_dg(res_state statp,
828 const u_char *buf, int buflen, u_char *ans,
829 int anssiz, int *terrno, int ns, int tries, int *v_circuit,
832 const HEADER *hp = (const HEADER *) buf;
833 HEADER *anhp = (HEADER *) ans;
834 const struct sockaddr *nsap;
836 struct timespec now, timeout, finish;
837 struct sockaddr_storage from;
838 ISC_SOCKLEN_T fromlen;
839 int resplen, seconds, n, s;
845 struct pollfd pollfd;
851 nsap = get_nsaddr(statp, ns);
852 nsaplen = get_salen(nsap);
853 if (EXT(statp).nssocks[ns] == -1) {
854 EXT(statp).nssocks[ns] = _socket(nsap->sa_family,
855 SOCK_DGRAM | SOCK_CLOEXEC, 0);
856 #if !defined(USE_POLL) && !defined(USE_KQUEUE)
857 if (EXT(statp).nssocks[ns] > highestFD) {
862 if (EXT(statp).nssocks[ns] < 0) {
864 case EPROTONOSUPPORT:
869 Perror(statp, stderr, "socket(dg)", errno);
873 Perror(statp, stderr, "socket(dg)", errno);
877 #ifndef CANNOT_CONNECT_DGRAM
879 * On a 4.3BSD+ machine (client and server,
880 * actually), sending to a nameserver datagram
881 * port with no nameserver will cause an
882 * ICMP port unreachable message to be returned.
883 * If our datagram socket is "connected" to the
884 * server, we get an ECONNREFUSED error on the next
885 * socket operation, and select returns if the
886 * error message is received. We can thus detect
887 * the absence of a nameserver without timing out.
889 * When the option "insecure1" is specified, we'd
890 * rather expect to see responses from an "unknown"
891 * address. In order to let the kernel accept such
892 * responses, do not connect the socket here.
893 * XXX: or do we need an explicit option to disable
896 if (!(statp->options & RES_INSECURE1) &&
897 _connect(EXT(statp).nssocks[ns], nsap, nsaplen) < 0) {
898 Aerror(statp, stderr, "connect(dg)", errno, nsap,
903 #endif /* !CANNOT_CONNECT_DGRAM */
904 Dprint(statp->options & RES_DEBUG,
905 (stdout, ";; new DG socket\n"))
907 s = EXT(statp).nssocks[ns];
908 #ifndef CANNOT_CONNECT_DGRAM
909 if (statp->options & RES_INSECURE1) {
911 (const char*)buf, buflen, 0, nsap, nsaplen) != buflen) {
912 Aerror(statp, stderr, "sendto", errno, nsap, nsaplen);
916 } else if (send(s, (const char*)buf, buflen, 0) != buflen) {
917 Perror(statp, stderr, "send", errno);
921 #else /* !CANNOT_CONNECT_DGRAM */
922 if (_sendto(s, (const char*)buf, buflen, 0, nsap, nsaplen) != buflen)
924 Aerror(statp, stderr, "sendto", errno, nsap, nsaplen);
928 #endif /* !CANNOT_CONNECT_DGRAM */
933 seconds = (statp->retrans << tries);
935 seconds /= statp->nscount;
939 timeout = evConsTime(seconds, 0);
940 finish = evAddTime(now, timeout);
946 if (evCmpTime(finish, now) > 0)
947 timeout = evSubTime(finish, now);
949 timeout = evConsTime(0, 0);
951 EV_SET(&kv, s, EVFILT_READ, EV_ADD | EV_ONESHOT, 0, 0, 0);
952 n = _kevent(kq, &kv, 1, &kv, 1, &timeout);
956 n = pselect(s + 1, &dsmask, NULL, NULL, &timeout, NULL);
959 timeout = evSubTime(finish, now);
960 if (timeout.tv_sec < 0)
961 timeout = evConsTime(0, 0);
962 polltimeout = 1000*timeout.tv_sec +
963 timeout.tv_nsec/1000000;
965 pollfd.events = POLLRDNORM;
966 n = _poll(&pollfd, 1, polltimeout);
967 #endif /* USE_POLL */
970 Dprint(statp->options & RES_DEBUG, (stdout, ";; timeout\n"));
978 Perror(statp, stderr, "kevent", errno);
981 Perror(statp, stderr, "select", errno);
983 Perror(statp, stderr, "poll", errno);
984 #endif /* USE_POLL */
994 fromlen = sizeof(from);
995 resplen = _recvfrom(s, (char*)ans, anssiz,0,
996 (struct sockaddr *)&from, &fromlen);
998 Perror(statp, stderr, "recvfrom", errno);
1003 if (resplen < HFIXEDSZ) {
1005 * Undersized message.
1007 Dprint(statp->options & RES_DEBUG,
1008 (stdout, ";; undersized: %d\n",
1014 if (hp->id != anhp->id) {
1016 * response from old query, ignore it.
1017 * XXX - potential security hazard could
1020 DprintQ((statp->options & RES_DEBUG) ||
1021 (statp->pfcode & RES_PRF_REPLY),
1022 (stdout, ";; old answer:\n"),
1023 ans, (resplen > anssiz) ? anssiz : resplen);
1026 if (!(statp->options & RES_INSECURE1) &&
1027 !res_ourserver_p(statp, (struct sockaddr *)&from)) {
1029 * response from wrong server? ignore it.
1030 * XXX - potential security hazard could
1033 DprintQ((statp->options & RES_DEBUG) ||
1034 (statp->pfcode & RES_PRF_REPLY),
1035 (stdout, ";; not our server:\n"),
1036 ans, (resplen > anssiz) ? anssiz : resplen);
1039 #ifdef RES_USE_EDNS0
1040 if (anhp->rcode == FORMERR && (statp->options & RES_USE_EDNS0) != 0U) {
1042 * Do not retry if the server do not understand EDNS0.
1043 * The case has to be captured here, as FORMERR packet do not
1044 * carry query section, hence res_queriesmatch() returns 0.
1046 DprintQ(statp->options & RES_DEBUG,
1047 (stdout, "server rejected query with EDNS0:\n"),
1048 ans, (resplen > anssiz) ? anssiz : resplen);
1049 /* record the error */
1050 statp->_flags |= RES_F_EDNS0ERR;
1055 if (!(statp->options & RES_INSECURE2) &&
1056 !res_queriesmatch(buf, buf + buflen,
1057 ans, ans + anssiz)) {
1059 * response contains wrong query? ignore it.
1060 * XXX - potential security hazard could
1063 DprintQ((statp->options & RES_DEBUG) ||
1064 (statp->pfcode & RES_PRF_REPLY),
1065 (stdout, ";; wrong query name:\n"),
1066 ans, (resplen > anssiz) ? anssiz : resplen);
1069 if (anhp->rcode == SERVFAIL ||
1070 anhp->rcode == NOTIMP ||
1071 anhp->rcode == REFUSED) {
1072 DprintQ(statp->options & RES_DEBUG,
1073 (stdout, "server rejected query:\n"),
1074 ans, (resplen > anssiz) ? anssiz : resplen);
1076 /* don't retry if called from dig */
1080 if (!(statp->options & RES_IGNTC) && anhp->tc) {
1082 * To get the rest of answer,
1083 * use TCP with same server.
1085 Dprint(statp->options & RES_DEBUG,
1086 (stdout, ";; truncated answer\n"));
1092 * All is well, or the error is fatal. Signal that the
1093 * next nameserver ought not be tried.
1099 Aerror(const res_state statp, FILE *file, const char *string, int error,
1100 const struct sockaddr *address, int alen)
1103 char hbuf[NI_MAXHOST];
1104 char sbuf[NI_MAXSERV];
1106 if ((statp->options & RES_DEBUG) != 0U) {
1107 if (getnameinfo(address, alen, hbuf, sizeof(hbuf),
1108 sbuf, sizeof(sbuf), niflags)) {
1109 strncpy(hbuf, "?", sizeof(hbuf) - 1);
1110 hbuf[sizeof(hbuf) - 1] = '\0';
1111 strncpy(sbuf, "?", sizeof(sbuf) - 1);
1112 sbuf[sizeof(sbuf) - 1] = '\0';
1114 fprintf(file, "res_send: %s ([%s].%s): %s\n",
1115 string, hbuf, sbuf, strerror(error));
1121 Perror(const res_state statp, FILE *file, const char *string, int error) {
1124 if ((statp->options & RES_DEBUG) != 0U)
1125 fprintf(file, "res_send: %s: %s\n",
1126 string, strerror(error));
1131 sock_eq(struct sockaddr *a, struct sockaddr *b) {
1132 struct sockaddr_in *a4, *b4;
1133 struct sockaddr_in6 *a6, *b6;
1135 if (a->sa_family != b->sa_family)
1137 switch (a->sa_family) {
1139 a4 = (struct sockaddr_in *)a;
1140 b4 = (struct sockaddr_in *)b;
1141 return a4->sin_port == b4->sin_port &&
1142 a4->sin_addr.s_addr == b4->sin_addr.s_addr;
1144 a6 = (struct sockaddr_in6 *)a;
1145 b6 = (struct sockaddr_in6 *)b;
1146 return a6->sin6_port == b6->sin6_port &&
1147 #ifdef HAVE_SIN6_SCOPE_ID
1148 a6->sin6_scope_id == b6->sin6_scope_id &&
1150 IN6_ARE_ADDR_EQUAL(&a6->sin6_addr, &b6->sin6_addr);
1156 #if defined(NEED_PSELECT) && !defined(USE_POLL) && !defined(USE_KQUEUE)
1157 /* XXX needs to move to the porting library. */
1159 pselect(int nfds, void *rfds, void *wfds, void *efds,
1160 struct timespec *tsp, const sigset_t *sigmask)
1162 struct timeval tv, *tvp;
1168 tv = evTimeVal(*tsp);
1172 sigprocmask(SIG_SETMASK, sigmask, &sigs);
1173 n = select(nfds, rfds, wfds, efds, tvp);
1175 sigprocmask(SIG_SETMASK, &sigs, NULL);
1177 *tsp = evTimeSpec(tv);