2 * Copyright (c) 1985, 1989, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
33 * Permission to use, copy, modify, and distribute this software for any
34 * purpose with or without fee is hereby granted, provided that the above
35 * copyright notice and this permission notice appear in all copies, and that
36 * the name of Digital Equipment Corporation not be used in advertising or
37 * publicity pertaining to distribution of the document or software without
38 * specific, written prior permission.
40 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
41 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
42 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
43 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
44 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
45 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
46 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
51 * Copyright (c) 2005 by Internet Systems Consortium, Inc. ("ISC")
52 * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
54 * Permission to use, copy, modify, and distribute this software for any
55 * purpose with or without fee is hereby granted, provided that the above
56 * copyright notice and this permission notice appear in all copies.
58 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
59 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
60 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
61 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
62 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
63 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
64 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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 1.18.10.1 2008/01/27 02:06:46 marka Exp $";
70 #endif /* LIBC_SCCS and not lint */
74 * Send query to name server and wait for reply.
77 #include "port_before.h"
79 #include "fd_setsize.h"
83 #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"
108 #include <sys/event.h>
112 #ifdef HAVE_STROPTS_H
116 #endif /* USE_POLL */
120 #include "un-namespace.h"
123 /* 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 __P((const struct sockaddr *));
137 static struct sockaddr * get_nsaddr __P((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);
359 if (getsockname(EXT(statp).nssocks[ns],
361 if (_getsockname(EXT(statp).nssocks[ns],
363 (struct sockaddr *)&peer, &peerlen) < 0) {
367 if (!sock_eq((struct sockaddr *)&peer,
368 get_nsaddr(statp, ns))) {
375 EXT(statp).nscount = 0;
380 * Maybe initialize our private copy of the ns_addr_list.
382 if (EXT(statp).nscount == 0) {
383 for (ns = 0; ns < statp->nscount; ns++) {
384 EXT(statp).nstimes[ns] = RES_MAXTIME;
385 EXT(statp).nssocks[ns] = -1;
386 if (!statp->nsaddr_list[ns].sin_family)
388 EXT(statp).ext->nsaddrs[ns].sin =
389 statp->nsaddr_list[ns];
391 EXT(statp).nscount = statp->nscount;
395 * Some resolvers want to even out the load on their nameservers.
396 * Note that RES_BLAST overrides RES_ROTATE.
398 if ((statp->options & RES_ROTATE) != 0U &&
399 (statp->options & RES_BLAST) == 0U) {
400 union res_sockaddr_union inu;
401 struct sockaddr_in ina;
402 int lastns = statp->nscount - 1;
406 if (EXT(statp).ext != NULL)
407 inu = EXT(statp).ext->nsaddrs[0];
408 ina = statp->nsaddr_list[0];
409 fd = EXT(statp).nssocks[0];
410 nstime = EXT(statp).nstimes[0];
411 for (ns = 0; ns < lastns; ns++) {
412 if (EXT(statp).ext != NULL)
413 EXT(statp).ext->nsaddrs[ns] =
414 EXT(statp).ext->nsaddrs[ns + 1];
415 statp->nsaddr_list[ns] = statp->nsaddr_list[ns + 1];
416 EXT(statp).nssocks[ns] = EXT(statp).nssocks[ns + 1];
417 EXT(statp).nstimes[ns] = EXT(statp).nstimes[ns + 1];
419 if (EXT(statp).ext != NULL)
420 EXT(statp).ext->nsaddrs[lastns] = inu;
421 statp->nsaddr_list[lastns] = ina;
422 EXT(statp).nssocks[lastns] = fd;
423 EXT(statp).nstimes[lastns] = nstime;
427 * Send request, RETRY times, or until successful.
429 for (tries = 0; tries < statp->retry; tries++) {
430 for (ns = 0; ns < statp->nscount; ns++) {
431 struct sockaddr *nsap;
433 nsap = get_nsaddr(statp, ns);
434 nsaplen = get_salen(nsap);
435 statp->_flags &= ~RES_F_LASTMASK;
436 statp->_flags |= (ns << RES_F_LASTSHIFT);
439 int done = 0, loops = 0;
444 act = (*statp->qhook)(&nsap, &buf, &buflen,
445 ans, anssiz, &resplen);
459 /* give the hook another try */
460 if (++loops < 42) /*doug adams*/
471 Dprint(((statp->options & RES_DEBUG) &&
472 getnameinfo(nsap, nsaplen, abuf, sizeof(abuf),
473 NULL, 0, niflags) == 0),
474 (stdout, ";; Querying server (# %d) address = %s\n",
479 /* Use VC; at most one attempt per server. */
480 tries = statp->retry;
481 n = send_vc(statp, buf, buflen, ans, anssiz, &terrno,
494 buf, buflen, ans, anssiz, &terrno,
495 ns, tries, &v_circuit, &gotsomewhere);
505 Dprint((statp->options & RES_DEBUG) ||
506 ((statp->pfcode & RES_PRF_REPLY) &&
507 (statp->pfcode & RES_PRF_HEAD1)),
508 (stdout, ";; got answer:\n"));
510 DprintQ((statp->options & RES_DEBUG) ||
511 (statp->pfcode & RES_PRF_REPLY),
513 ans, (resplen > anssiz) ? anssiz : resplen);
516 * If we have temporarily opened a virtual circuit,
517 * or if we haven't been asked to keep a socket open,
520 if ((v_circuit && (statp->options & RES_USEVC) == 0U) ||
521 (statp->options & RES_STAYOPEN) == 0U) {
525 int done = 0, loops = 0;
530 act = (*statp->rhook)(nsap, buf, buflen,
531 ans, anssiz, &resplen);
541 /* give the hook another try */
542 if (++loops < 42) /*doug adams*/
566 errno = ECONNREFUSED; /*%< no nameservers found */
568 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,
653 if (_getpeername(statp->_vcsock,
655 (struct sockaddr *)&peer, &size) < 0 ||
656 !sock_eq((struct sockaddr *)&peer, nsap)) {
658 statp->_flags &= ~RES_F_VC;
662 if (statp->_vcsock < 0 || (statp->_flags & RES_F_VC) == 0) {
663 if (statp->_vcsock >= 0)
666 statp->_vcsock = socket(nsap->sa_family, SOCK_STREAM, 0);
668 statp->_vcsock = _socket(nsap->sa_family, SOCK_STREAM, 0);
670 #if !defined(USE_POLL) && !defined(USE_KQUEUE)
671 if (statp->_vcsock > highestFD) {
676 if (statp->_vcsock < 0) {
678 case EPROTONOSUPPORT:
683 Perror(statp, stderr, "socket(vc)", errno);
687 Perror(statp, stderr, "socket(vc)", errno);
693 * Disable generation of SIGPIPE when writing to a closed
694 * socket. Write should return -1 and set errno to EPIPE
697 * Push on even if setsockopt(SO_NOSIGPIPE) fails.
699 (void)_setsockopt(statp->_vcsock, SOL_SOCKET, SO_NOSIGPIPE, &on,
704 if (connect(statp->_vcsock, nsap, nsaplen) < 0) {
706 if (_connect(statp->_vcsock, nsap, nsaplen) < 0) {
709 Aerror(statp, stderr, "connect/vc", errno, nsap,
714 statp->_flags |= RES_F_VC;
718 * Send length & message
720 ns_put16((u_short)buflen, (u_char*)&len);
721 iov[0] = evConsIovec(&len, INT16SZ);
723 iov[1] = evConsIovec(tmp, buflen);
725 if (writev(statp->_vcsock, iov, 2) != (INT16SZ + buflen)) {
727 if (_writev(statp->_vcsock, iov, 2) != (INT16SZ + buflen)) {
730 Perror(statp, stderr, "write failed", errno);
735 * Receive length & response
741 while ((n = read(statp->_vcsock, (char *)cp, (int)len)) > 0) {
743 while ((n = _read(statp->_vcsock, (char *)cp, (int)len)) > 0) {
751 Perror(statp, stderr, "read failed", errno);
754 * A long running process might get its TCP
755 * connection reset if the remote server was
756 * restarted. Requery the server instead of
757 * trying a new one. When there is only one
758 * server, this means that a query might work
759 * instead of failing. We only allow one reset
760 * per query to prevent looping.
762 if (*terrno == ECONNRESET && !connreset) {
770 resplen = ns_get16(ans);
771 if (resplen > anssiz) {
772 Dprint(statp->options & RES_DEBUG,
773 (stdout, ";; response truncated\n")
779 if (len < HFIXEDSZ) {
781 * Undersized message.
783 Dprint(statp->options & RES_DEBUG,
784 (stdout, ";; undersized: %d\n", len));
791 while (len != 0 && (n = read(statp->_vcsock, (char *)cp, (int)len)) > 0){
793 while (len != 0 && (n = _read(statp->_vcsock, (char *)cp, (int)len)) > 0){
800 Perror(statp, stderr, "read(vc)", errno);
806 * Flush rest of answer so connection stays in synch.
809 len = resplen - anssiz;
814 n = read(statp->_vcsock, junk,
816 n = _read(statp->_vcsock, junk,
818 (len > sizeof junk) ? sizeof junk : len);
826 * If the calling applicating has bailed out of
827 * a previous call and failed to arrange to have
828 * the circuit closed or the server has got
829 * itself confused, then drop the packet and
830 * wait for the correct one.
832 if (hp->id != anhp->id) {
833 DprintQ((statp->options & RES_DEBUG) ||
834 (statp->pfcode & RES_PRF_REPLY),
835 (stdout, ";; old answer (unexpected):\n"),
836 ans, (resplen > anssiz) ? anssiz: resplen);
841 * All is well, or the error is fatal. Signal that the
842 * next nameserver ought not be tried.
848 send_dg(res_state statp,
852 const u_char *buf, int buflen, u_char *ans,
853 int anssiz, int *terrno, int ns, int tries, int *v_circuit,
856 const HEADER *hp = (const HEADER *) buf;
857 HEADER *anhp = (HEADER *) ans;
858 const struct sockaddr *nsap;
860 struct timespec now, timeout, finish;
861 struct sockaddr_storage from;
862 ISC_SOCKLEN_T fromlen;
863 int resplen, seconds, n, s;
869 struct pollfd pollfd;
875 nsap = get_nsaddr(statp, ns);
876 nsaplen = get_salen(nsap);
877 if (EXT(statp).nssocks[ns] == -1) {
879 EXT(statp).nssocks[ns] = socket(nsap->sa_family, SOCK_DGRAM, 0);
881 EXT(statp).nssocks[ns] = _socket(nsap->sa_family, SOCK_DGRAM, 0);
883 #if !defined(USE_POLL) && !defined(USE_KQUEUE)
884 if (EXT(statp).nssocks[ns] > highestFD) {
889 if (EXT(statp).nssocks[ns] < 0) {
891 case EPROTONOSUPPORT:
896 Perror(statp, stderr, "socket(dg)", errno);
900 Perror(statp, stderr, "socket(dg)", errno);
904 #ifndef CANNOT_CONNECT_DGRAM
906 * On a 4.3BSD+ machine (client and server,
907 * actually), sending to a nameserver datagram
908 * port with no nameserver will cause an
909 * ICMP port unreachable message to be returned.
910 * If our datagram socket is "connected" to the
911 * server, we get an ECONNREFUSED error on the next
912 * socket operation, and select returns if the
913 * error message is received. We can thus detect
914 * the absence of a nameserver without timing out.
917 * When the option "insecure1" is specified, we'd
918 * rather expect to see responses from an "unknown"
919 * address. In order to let the kernel accept such
920 * responses, do not connect the socket here.
921 * XXX: or do we need an explicit option to disable
924 if (!(statp->options & RES_INSECURE1) &&
926 connect(EXT(statp).nssocks[ns], nsap, nsaplen) < 0) {
928 _connect(EXT(statp).nssocks[ns], nsap, nsaplen) < 0) {
930 Aerror(statp, stderr, "connect(dg)", errno, nsap,
935 #endif /* !CANNOT_CONNECT_DGRAM */
936 Dprint(statp->options & RES_DEBUG,
937 (stdout, ";; new DG socket\n"))
939 s = EXT(statp).nssocks[ns];
940 #ifndef CANNOT_CONNECT_DGRAM
941 if (statp->options & RES_INSECURE1) {
947 (const char*)buf, buflen, 0, nsap, nsaplen) != buflen) {
948 Aerror(statp, stderr, "sendto", errno, nsap, nsaplen);
952 } else if (send(s, (const char*)buf, buflen, 0) != buflen) {
953 Perror(statp, stderr, "send", errno);
957 #else /* !CANNOT_CONNECT_DGRAM */
959 if (sendto(s, (const char*)buf, buflen, 0, nsap, nsaplen) != buflen)
961 if (_sendto(s, (const char*)buf, buflen, 0, nsap, nsaplen) != buflen)
964 Aerror(statp, stderr, "sendto", errno, nsap, nsaplen);
968 #endif /* !CANNOT_CONNECT_DGRAM */
973 seconds = (statp->retrans << tries);
975 seconds /= statp->nscount;
979 timeout = evConsTime(seconds, 0);
980 finish = evAddTime(now, timeout);
986 if (evCmpTime(finish, now) > 0)
987 timeout = evSubTime(finish, now);
989 timeout = evConsTime(0, 0);
991 EV_SET(&kv, s, EVFILT_READ, EV_ADD | EV_ONESHOT, 0, 0, 0);
992 n = _kevent(kq, &kv, 1, &kv, 1, &timeout);
996 n = pselect(s + 1, &dsmask, NULL, NULL, &timeout, NULL);
999 timeout = evSubTime(finish, now);
1000 if (timeout.tv_sec < 0)
1001 timeout = evConsTime(0, 0);
1002 polltimeout = 1000*timeout.tv_sec +
1003 timeout.tv_nsec/1000000;
1005 pollfd.events = POLLRDNORM;
1006 n = poll(&pollfd, 1, polltimeout);
1007 #endif /* USE_POLL */
1010 Dprint(statp->options & RES_DEBUG, (stdout, ";; timeout\n"));
1018 Perror(statp, stderr, "kevent", errno);
1021 Perror(statp, stderr, "select", errno);
1023 Perror(statp, stderr, "poll", errno);
1024 #endif /* USE_POLL */
1034 fromlen = sizeof(from);
1036 resplen = recvfrom(s, (char*)ans, anssiz,0,
1038 resplen = _recvfrom(s, (char*)ans, anssiz,0,
1040 (struct sockaddr *)&from, &fromlen);
1042 Perror(statp, stderr, "recvfrom", errno);
1047 if (resplen < HFIXEDSZ) {
1049 * Undersized message.
1051 Dprint(statp->options & RES_DEBUG,
1052 (stdout, ";; undersized: %d\n",
1058 if (hp->id != anhp->id) {
1060 * response from old query, ignore it.
1061 * XXX - potential security hazard could
1064 DprintQ((statp->options & RES_DEBUG) ||
1065 (statp->pfcode & RES_PRF_REPLY),
1066 (stdout, ";; old answer:\n"),
1067 ans, (resplen > anssiz) ? anssiz : resplen);
1070 if (!(statp->options & RES_INSECURE1) &&
1071 !res_ourserver_p(statp, (struct sockaddr *)&from)) {
1073 * response from wrong server? ignore it.
1074 * XXX - potential security hazard could
1077 DprintQ((statp->options & RES_DEBUG) ||
1078 (statp->pfcode & RES_PRF_REPLY),
1079 (stdout, ";; not our server:\n"),
1080 ans, (resplen > anssiz) ? anssiz : resplen);
1083 #ifdef RES_USE_EDNS0
1084 if (anhp->rcode == FORMERR && (statp->options & RES_USE_EDNS0) != 0U) {
1086 * Do not retry if the server do not understand EDNS0.
1087 * The case has to be captured here, as FORMERR packet do not
1088 * carry query section, hence res_queriesmatch() returns 0.
1090 DprintQ(statp->options & RES_DEBUG,
1091 (stdout, "server rejected query with EDNS0:\n"),
1092 ans, (resplen > anssiz) ? anssiz : resplen);
1093 /* record the error */
1094 statp->_flags |= RES_F_EDNS0ERR;
1099 if (!(statp->options & RES_INSECURE2) &&
1100 !res_queriesmatch(buf, buf + buflen,
1101 ans, ans + anssiz)) {
1103 * response contains wrong query? ignore it.
1104 * XXX - potential security hazard could
1107 DprintQ((statp->options & RES_DEBUG) ||
1108 (statp->pfcode & RES_PRF_REPLY),
1109 (stdout, ";; wrong query name:\n"),
1110 ans, (resplen > anssiz) ? anssiz : resplen);
1113 if (anhp->rcode == SERVFAIL ||
1114 anhp->rcode == NOTIMP ||
1115 anhp->rcode == REFUSED) {
1116 DprintQ(statp->options & RES_DEBUG,
1117 (stdout, "server rejected query:\n"),
1118 ans, (resplen > anssiz) ? anssiz : resplen);
1120 /* don't retry if called from dig */
1124 if (!(statp->options & RES_IGNTC) && anhp->tc) {
1126 * To get the rest of answer,
1127 * use TCP with same server.
1129 Dprint(statp->options & RES_DEBUG,
1130 (stdout, ";; truncated answer\n"));
1136 * All is well, or the error is fatal. Signal that the
1137 * next nameserver ought not be tried.
1143 Aerror(const res_state statp, FILE *file, const char *string, int error,
1144 const struct sockaddr *address, int alen)
1147 char hbuf[NI_MAXHOST];
1148 char sbuf[NI_MAXSERV];
1152 if ((statp->options & RES_DEBUG) != 0U) {
1153 if (getnameinfo(address, alen, hbuf, sizeof(hbuf),
1154 sbuf, sizeof(sbuf), niflags)) {
1155 strncpy(hbuf, "?", sizeof(hbuf) - 1);
1156 hbuf[sizeof(hbuf) - 1] = '\0';
1157 strncpy(sbuf, "?", sizeof(sbuf) - 1);
1158 sbuf[sizeof(sbuf) - 1] = '\0';
1160 fprintf(file, "res_send: %s ([%s].%s): %s\n",
1161 string, hbuf, sbuf, strerror(error));
1167 Perror(const res_state statp, FILE *file, const char *string, int error) {
1170 if ((statp->options & RES_DEBUG) != 0U)
1171 fprintf(file, "res_send: %s: %s\n",
1172 string, strerror(error));
1177 sock_eq(struct sockaddr *a, struct sockaddr *b) {
1178 struct sockaddr_in *a4, *b4;
1179 struct sockaddr_in6 *a6, *b6;
1181 if (a->sa_family != b->sa_family)
1183 switch (a->sa_family) {
1185 a4 = (struct sockaddr_in *)a;
1186 b4 = (struct sockaddr_in *)b;
1187 return a4->sin_port == b4->sin_port &&
1188 a4->sin_addr.s_addr == b4->sin_addr.s_addr;
1190 a6 = (struct sockaddr_in6 *)a;
1191 b6 = (struct sockaddr_in6 *)b;
1192 return a6->sin6_port == b6->sin6_port &&
1193 #ifdef HAVE_SIN6_SCOPE_ID
1194 a6->sin6_scope_id == b6->sin6_scope_id &&
1196 IN6_ARE_ADDR_EQUAL(&a6->sin6_addr, &b6->sin6_addr);
1202 #if defined(NEED_PSELECT) && !defined(USE_POLL) && !defined(USE_KQUEUE)
1203 /* XXX needs to move to the porting library. */
1205 pselect(int nfds, void *rfds, void *wfds, void *efds,
1206 struct timespec *tsp, const sigset_t *sigmask)
1208 struct timeval tv, *tvp;
1214 tv = evTimeVal(*tsp);
1218 sigprocmask(SIG_SETMASK, sigmask, &sigs);
1219 n = select(nfds, rfds, wfds, efds, tvp);
1221 sigprocmask(SIG_SETMASK, &sigs, NULL);
1223 *tsp = evTimeSpec(tv);