2 * Portions Copyright (C) 2004-2009 Internet Systems Consortium, Inc. ("ISC")
3 * Portions Copyright (C) 1996-2003 Internet Software Consortium.
5 * Permission to use, copy, modify, and/or distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
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10 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
11 * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
12 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
13 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
14 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
15 * PERFORMANCE OF THIS SOFTWARE.
19 * Copyright (c) 1985, 1989, 1993
20 * The Regents of the University of California. All rights reserved.
22 * Redistribution and use in source and binary forms, with or without
23 * modification, are permitted provided that the following conditions
25 * 1. Redistributions of source code must retain the above copyright
26 * notice, this list of conditions and the following disclaimer.
27 * 2. Redistributions in binary form must reproduce the above copyright
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31 * may be used to endorse or promote products derived from this software
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41 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
42 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
43 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
48 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
50 * Permission to use, copy, modify, and distribute this software for any
51 * purpose with or without fee is hereby granted, provided that the above
52 * copyright notice and this permission notice appear in all copies, and that
53 * the name of Digital Equipment Corporation not be used in advertising or
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55 * specific, written prior permission.
57 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
58 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
59 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
60 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
61 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
62 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
63 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
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"
80 #if !defined(USE_KQUEUE) && !defined(USE_POLL)
81 #include "fd_setsize.h"
84 #include "namespace.h"
85 #include <sys/param.h>
87 #include <sys/socket.h>
90 #include <netinet/in.h>
91 #include <arpa/nameser.h>
92 #include <arpa/inet.h>
103 #include <isc/eventlib.h>
105 #include "port_after.h"
108 #include <sys/event.h>
111 #ifdef HAVE_STROPTS_H
115 #endif /* USE_POLL */
118 #include "un-namespace.h"
120 /* Options. Leave them on. */
124 #include "res_debug.h"
125 #include "res_private.h"
127 #define EXT(res) ((res)->_u._ext)
129 #if !defined(USE_POLL) && !defined(USE_KQUEUE)
130 static const int highestFD = FD_SETSIZE - 1;
135 static int get_salen(const struct sockaddr *);
136 static struct sockaddr * get_nsaddr(res_state, size_t);
137 static int send_vc(res_state, const u_char *, int,
138 u_char *, int, int *, int);
139 static int send_dg(res_state,
144 u_char *, int, int *, int, int,
146 static void Aerror(const res_state, FILE *, const char *, int,
147 const struct sockaddr *, int);
148 static void Perror(const res_state, FILE *, const char *, int);
149 static int sock_eq(struct sockaddr *, struct sockaddr *);
150 #if defined(NEED_PSELECT) && !defined(USE_POLL) && !defined(USE_KQUEUE)
151 static int pselect(int, void *, void *, void *,
155 void res_pquery(const res_state, const u_char *, int, FILE *);
157 static const int niflags = NI_NUMERICHOST | NI_NUMERICSERV;
162 * looks up "ina" in _res.ns_addr_list[]
169 *\li paul vixie, 29may94
172 res_ourserver_p(const res_state statp, const struct sockaddr *sa) {
173 const struct sockaddr_in *inp, *srv;
174 const struct sockaddr_in6 *in6p, *srv6;
177 switch (sa->sa_family) {
179 inp = (const struct sockaddr_in *)sa;
180 for (ns = 0; ns < statp->nscount; ns++) {
181 srv = (struct sockaddr_in *)get_nsaddr(statp, ns);
182 if (srv->sin_family == inp->sin_family &&
183 srv->sin_port == inp->sin_port &&
184 (srv->sin_addr.s_addr == INADDR_ANY ||
185 srv->sin_addr.s_addr == inp->sin_addr.s_addr))
190 if (EXT(statp).ext == NULL)
192 in6p = (const struct sockaddr_in6 *)sa;
193 for (ns = 0; ns < statp->nscount; ns++) {
194 srv6 = (struct sockaddr_in6 *)get_nsaddr(statp, ns);
195 if (srv6->sin6_family == in6p->sin6_family &&
196 srv6->sin6_port == in6p->sin6_port &&
197 #ifdef HAVE_SIN6_SCOPE_ID
198 (srv6->sin6_scope_id == 0 ||
199 srv6->sin6_scope_id == in6p->sin6_scope_id) &&
201 (IN6_IS_ADDR_UNSPECIFIED(&srv6->sin6_addr) ||
202 IN6_ARE_ADDR_EQUAL(&srv6->sin6_addr, &in6p->sin6_addr)))
213 * look for (name,type,class) in the query section of packet (buf,eom)
216 *\li buf + HFIXEDSZ <= eom
219 *\li -1 : format error
224 *\li paul vixie, 29may94
227 res_nameinquery(const char *name, int type, int class,
228 const u_char *buf, const u_char *eom)
230 const u_char *cp = buf + HFIXEDSZ;
231 int qdcount = ntohs(((const HEADER*)buf)->qdcount);
233 while (qdcount-- > 0) {
234 char tname[MAXDNAME+1];
235 int n, ttype, tclass;
237 n = dn_expand(buf, eom, cp, tname, sizeof tname);
241 if (cp + 2 * INT16SZ > eom)
243 ttype = ns_get16(cp); cp += INT16SZ;
244 tclass = ns_get16(cp); cp += INT16SZ;
245 if (ttype == type && tclass == class &&
246 ns_samename(tname, name) == 1)
253 * is there a 1:1 mapping of (name,type,class)
254 * in (buf1,eom1) and (buf2,eom2)?
257 *\li -1 : format error
258 *\li 0 : not a 1:1 mapping
259 *\li >0 : is a 1:1 mapping
262 *\li paul vixie, 29may94
265 res_queriesmatch(const u_char *buf1, const u_char *eom1,
266 const u_char *buf2, const u_char *eom2)
268 const u_char *cp = buf1 + HFIXEDSZ;
269 int qdcount = ntohs(((const HEADER*)buf1)->qdcount);
271 if (buf1 + HFIXEDSZ > eom1 || buf2 + HFIXEDSZ > eom2)
275 * Only header section present in replies to
276 * dynamic update packets.
278 if ((((const HEADER *)buf1)->opcode == ns_o_update) &&
279 (((const HEADER *)buf2)->opcode == ns_o_update))
282 if (qdcount != ntohs(((const HEADER*)buf2)->qdcount))
284 while (qdcount-- > 0) {
285 char tname[MAXDNAME+1];
286 int n, ttype, tclass;
288 n = dn_expand(buf1, eom1, cp, tname, sizeof tname);
292 if (cp + 2 * INT16SZ > eom1)
294 ttype = ns_get16(cp); cp += INT16SZ;
295 tclass = ns_get16(cp); cp += INT16SZ;
296 if (!res_nameinquery(tname, ttype, tclass, buf2, eom2))
303 res_nsend(res_state statp,
304 const u_char *buf, int buflen, u_char *ans, int anssiz)
306 int gotsomewhere, terrno, tries, v_circuit, resplen, ns, n;
310 char abuf[NI_MAXHOST];
312 /* No name servers or res_init() failure */
313 if (statp->nscount == 0 || EXT(statp).ext == NULL) {
317 if (anssiz < HFIXEDSZ) {
321 DprintQ((statp->options & RES_DEBUG) || (statp->pfcode & RES_PRF_QUERY),
322 (stdout, ";; res_send()\n"), buf, buflen);
323 v_circuit = (statp->options & RES_USEVC) || buflen > PACKETSZ;
328 if ((kq = kqueue()) < 0) {
329 Perror(statp, stderr, "kqueue", errno);
335 * If the ns_addr_list in the resolver context has changed, then
336 * invalidate our cached copy and the associated timing data.
338 if (EXT(statp).nscount != 0) {
340 struct sockaddr_storage peer;
341 ISC_SOCKLEN_T peerlen;
343 if (EXT(statp).nscount != statp->nscount)
346 for (ns = 0; ns < statp->nscount; ns++) {
347 if (statp->nsaddr_list[ns].sin_family &&
348 !sock_eq((struct sockaddr *)&statp->nsaddr_list[ns],
349 (struct sockaddr *)&EXT(statp).ext->nsaddrs[ns])) {
354 if (EXT(statp).nssocks[ns] == -1)
356 peerlen = sizeof(peer);
357 if (_getpeername(EXT(statp).nssocks[ns],
358 (struct sockaddr *)&peer, &peerlen) < 0) {
362 if (!sock_eq((struct sockaddr *)&peer,
363 get_nsaddr(statp, ns))) {
370 EXT(statp).nscount = 0;
375 * Maybe initialize our private copy of the ns_addr_list.
377 if (EXT(statp).nscount == 0) {
378 for (ns = 0; ns < statp->nscount; ns++) {
379 EXT(statp).nstimes[ns] = RES_MAXTIME;
380 EXT(statp).nssocks[ns] = -1;
381 if (!statp->nsaddr_list[ns].sin_family)
383 EXT(statp).ext->nsaddrs[ns].sin =
384 statp->nsaddr_list[ns];
386 EXT(statp).nscount = statp->nscount;
390 * Some resolvers want to even out the load on their nameservers.
391 * Note that RES_BLAST overrides RES_ROTATE.
393 if ((statp->options & RES_ROTATE) != 0U &&
394 (statp->options & RES_BLAST) == 0U) {
395 union res_sockaddr_union inu;
396 struct sockaddr_in ina;
397 int lastns = statp->nscount - 1;
401 if (EXT(statp).ext != NULL)
402 inu = EXT(statp).ext->nsaddrs[0];
403 ina = statp->nsaddr_list[0];
404 fd = EXT(statp).nssocks[0];
405 nstime = EXT(statp).nstimes[0];
406 for (ns = 0; ns < lastns; ns++) {
407 if (EXT(statp).ext != NULL)
408 EXT(statp).ext->nsaddrs[ns] =
409 EXT(statp).ext->nsaddrs[ns + 1];
410 statp->nsaddr_list[ns] = statp->nsaddr_list[ns + 1];
411 EXT(statp).nssocks[ns] = EXT(statp).nssocks[ns + 1];
412 EXT(statp).nstimes[ns] = EXT(statp).nstimes[ns + 1];
414 if (EXT(statp).ext != NULL)
415 EXT(statp).ext->nsaddrs[lastns] = inu;
416 statp->nsaddr_list[lastns] = ina;
417 EXT(statp).nssocks[lastns] = fd;
418 EXT(statp).nstimes[lastns] = nstime;
422 * Send request, RETRY times, or until successful.
424 for (tries = 0; tries < statp->retry; tries++) {
425 for (ns = 0; ns < statp->nscount; ns++) {
426 struct sockaddr *nsap;
428 nsap = get_nsaddr(statp, ns);
429 nsaplen = get_salen(nsap);
430 statp->_flags &= ~RES_F_LASTMASK;
431 statp->_flags |= (ns << RES_F_LASTSHIFT);
434 int done = 0, loops = 0;
439 act = (*statp->qhook)(&nsap, &buf, &buflen,
440 ans, anssiz, &resplen);
454 /* give the hook another try */
455 if (++loops < 42) /*doug adams*/
466 Dprint(((statp->options & RES_DEBUG) &&
467 getnameinfo(nsap, nsaplen, abuf, sizeof(abuf),
468 NULL, 0, niflags) == 0),
469 (stdout, ";; Querying server (# %d) address = %s\n",
474 /* Use VC; at most one attempt per server. */
475 tries = statp->retry;
476 n = send_vc(statp, buf, buflen, ans, anssiz, &terrno,
489 buf, buflen, ans, anssiz, &terrno,
490 ns, tries, &v_circuit, &gotsomewhere);
500 Dprint((statp->options & RES_DEBUG) ||
501 ((statp->pfcode & RES_PRF_REPLY) &&
502 (statp->pfcode & RES_PRF_HEAD1)),
503 (stdout, ";; got answer:\n"));
505 DprintQ((statp->options & RES_DEBUG) ||
506 (statp->pfcode & RES_PRF_REPLY),
508 ans, (resplen > anssiz) ? anssiz : resplen);
511 * If we have temporarily opened a virtual circuit,
512 * or if we haven't been asked to keep a socket open,
515 if ((v_circuit && (statp->options & RES_USEVC) == 0U) ||
516 (statp->options & RES_STAYOPEN) == 0U) {
520 int done = 0, loops = 0;
525 act = (*statp->rhook)(nsap, buf, buflen,
526 ans, anssiz, &resplen);
536 /* give the hook another try */
537 if (++loops < 42) /*doug adams*/
561 errno = ECONNREFUSED; /*%< no nameservers found */
563 errno = ETIMEDOUT; /*%< no answer obtained */
578 get_salen(const struct sockaddr *sa)
582 /* There are people do not set sa_len. Be forgiving to them. */
587 if (sa->sa_family == AF_INET)
588 return (sizeof(struct sockaddr_in));
589 else if (sa->sa_family == AF_INET6)
590 return (sizeof(struct sockaddr_in6));
592 return (0); /*%< unknown, die on connect */
596 * pick appropriate nsaddr_list for use. see res_init() for initialization.
598 static struct sockaddr *
599 get_nsaddr(res_state statp, size_t n)
602 if (!statp->nsaddr_list[n].sin_family && EXT(statp).ext) {
604 * - EXT(statp).ext->nsaddrs[n] holds an address that is larger
605 * than struct sockaddr, and
606 * - user code did not update statp->nsaddr_list[n].
608 return (struct sockaddr *)(void *)&EXT(statp).ext->nsaddrs[n];
611 * - user code updated statp->nsaddr_list[n], or
612 * - statp->nsaddr_list[n] has the same content as
613 * EXT(statp).ext->nsaddrs[n].
615 return (struct sockaddr *)(void *)&statp->nsaddr_list[n];
620 send_vc(res_state statp,
621 const u_char *buf, int buflen, u_char *ans, int anssiz,
624 const HEADER *hp = (const HEADER *) buf;
625 HEADER *anhp = (HEADER *) ans;
626 struct sockaddr *nsap;
628 int truncating, connreset, resplen, n;
637 nsap = get_nsaddr(statp, ns);
638 nsaplen = get_salen(nsap);
644 /* Are we still talking to whom we want to talk to? */
645 if (statp->_vcsock >= 0 && (statp->_flags & RES_F_VC) != 0) {
646 struct sockaddr_storage peer;
647 ISC_SOCKLEN_T size = sizeof peer;
649 if (_getpeername(statp->_vcsock,
650 (struct sockaddr *)&peer, &size) < 0 ||
651 !sock_eq((struct sockaddr *)&peer, nsap)) {
653 statp->_flags &= ~RES_F_VC;
657 if (statp->_vcsock < 0 || (statp->_flags & RES_F_VC) == 0) {
658 if (statp->_vcsock >= 0)
661 statp->_vcsock = _socket(nsap->sa_family, SOCK_STREAM |
663 #if !defined(USE_POLL) && !defined(USE_KQUEUE)
664 if (statp->_vcsock > highestFD) {
669 if (statp->_vcsock < 0) {
671 case EPROTONOSUPPORT:
676 Perror(statp, stderr, "socket(vc)", errno);
680 Perror(statp, stderr, "socket(vc)", errno);
686 * Disable generation of SIGPIPE when writing to a closed
687 * socket. Write should return -1 and set errno to EPIPE
690 * Push on even if setsockopt(SO_NOSIGPIPE) fails.
692 (void)_setsockopt(statp->_vcsock, SOL_SOCKET, SO_NOSIGPIPE, &on,
696 if (_connect(statp->_vcsock, nsap, nsaplen) < 0) {
698 Aerror(statp, stderr, "connect/vc", errno, nsap,
703 statp->_flags |= RES_F_VC;
707 * Send length & message
709 ns_put16((u_short)buflen, (u_char*)&len);
710 iov[0] = evConsIovec(&len, INT16SZ);
712 iov[1] = evConsIovec(tmp, buflen);
713 if (_writev(statp->_vcsock, iov, 2) != (INT16SZ + buflen)) {
715 Perror(statp, stderr, "write failed", errno);
720 * Receive length & response
725 while ((n = _read(statp->_vcsock, (char *)cp, (int)len)) > 0) {
732 Perror(statp, stderr, "read failed", errno);
735 * A long running process might get its TCP
736 * connection reset if the remote server was
737 * restarted. Requery the server instead of
738 * trying a new one. When there is only one
739 * server, this means that a query might work
740 * instead of failing. We only allow one reset
741 * per query to prevent looping.
743 if (*terrno == ECONNRESET && !connreset) {
751 resplen = ns_get16(ans);
752 if (resplen > anssiz) {
753 Dprint(statp->options & RES_DEBUG,
754 (stdout, ";; response truncated\n")
760 if (len < HFIXEDSZ) {
762 * Undersized message.
764 Dprint(statp->options & RES_DEBUG,
765 (stdout, ";; undersized: %d\n", len));
772 (n = _read(statp->_vcsock, (char *)cp, (int)len)) > 0) {
778 Perror(statp, stderr, "read(vc)", errno);
784 * Flush rest of answer so connection stays in synch.
787 len = resplen - anssiz;
791 n = _read(statp->_vcsock, junk,
792 (len > sizeof junk) ? sizeof junk : len);
800 * If the calling applicating has bailed out of
801 * a previous call and failed to arrange to have
802 * the circuit closed or the server has got
803 * itself confused, then drop the packet and
804 * wait for the correct one.
806 if (hp->id != anhp->id) {
807 DprintQ((statp->options & RES_DEBUG) ||
808 (statp->pfcode & RES_PRF_REPLY),
809 (stdout, ";; old answer (unexpected):\n"),
810 ans, (resplen > anssiz) ? anssiz: resplen);
815 * All is well, or the error is fatal. Signal that the
816 * next nameserver ought not be tried.
822 send_dg(res_state statp,
826 const u_char *buf, int buflen, u_char *ans,
827 int anssiz, int *terrno, int ns, int tries, int *v_circuit,
830 const HEADER *hp = (const HEADER *) buf;
831 HEADER *anhp = (HEADER *) ans;
832 const struct sockaddr *nsap;
834 struct timespec now, timeout, finish;
835 struct sockaddr_storage from;
836 ISC_SOCKLEN_T fromlen;
837 int resplen, seconds, n, s;
843 struct pollfd pollfd;
849 nsap = get_nsaddr(statp, ns);
850 nsaplen = get_salen(nsap);
851 if (EXT(statp).nssocks[ns] == -1) {
852 EXT(statp).nssocks[ns] = _socket(nsap->sa_family,
853 SOCK_DGRAM | SOCK_CLOEXEC, 0);
854 #if !defined(USE_POLL) && !defined(USE_KQUEUE)
855 if (EXT(statp).nssocks[ns] > highestFD) {
860 if (EXT(statp).nssocks[ns] < 0) {
862 case EPROTONOSUPPORT:
867 Perror(statp, stderr, "socket(dg)", errno);
871 Perror(statp, stderr, "socket(dg)", errno);
875 #ifndef CANNOT_CONNECT_DGRAM
877 * On a 4.3BSD+ machine (client and server,
878 * actually), sending to a nameserver datagram
879 * port with no nameserver will cause an
880 * ICMP port unreachable message to be returned.
881 * If our datagram socket is "connected" to the
882 * server, we get an ECONNREFUSED error on the next
883 * socket operation, and select returns if the
884 * error message is received. We can thus detect
885 * the absence of a nameserver without timing out.
887 * When the option "insecure1" is specified, we'd
888 * rather expect to see responses from an "unknown"
889 * address. In order to let the kernel accept such
890 * responses, do not connect the socket here.
891 * XXX: or do we need an explicit option to disable
894 if (!(statp->options & RES_INSECURE1) &&
895 _connect(EXT(statp).nssocks[ns], nsap, nsaplen) < 0) {
896 Aerror(statp, stderr, "connect(dg)", errno, nsap,
901 #endif /* !CANNOT_CONNECT_DGRAM */
902 Dprint(statp->options & RES_DEBUG,
903 (stdout, ";; new DG socket\n"))
905 s = EXT(statp).nssocks[ns];
906 #ifndef CANNOT_CONNECT_DGRAM
907 if (statp->options & RES_INSECURE1) {
909 (const char*)buf, buflen, 0, nsap, nsaplen) != buflen) {
910 Aerror(statp, stderr, "sendto", errno, nsap, nsaplen);
914 } else if (send(s, (const char*)buf, buflen, 0) != buflen) {
915 Perror(statp, stderr, "send", errno);
919 #else /* !CANNOT_CONNECT_DGRAM */
920 if (_sendto(s, (const char*)buf, buflen, 0, nsap, nsaplen) != buflen)
922 Aerror(statp, stderr, "sendto", errno, nsap, nsaplen);
926 #endif /* !CANNOT_CONNECT_DGRAM */
931 seconds = (statp->retrans << tries);
933 seconds /= statp->nscount;
937 timeout = evConsTime(seconds, 0);
938 finish = evAddTime(now, timeout);
944 if (evCmpTime(finish, now) > 0)
945 timeout = evSubTime(finish, now);
947 timeout = evConsTime(0, 0);
949 EV_SET(&kv, s, EVFILT_READ, EV_ADD | EV_ONESHOT, 0, 0, 0);
950 n = _kevent(kq, &kv, 1, &kv, 1, &timeout);
954 n = pselect(s + 1, &dsmask, NULL, NULL, &timeout, NULL);
957 timeout = evSubTime(finish, now);
958 if (timeout.tv_sec < 0)
959 timeout = evConsTime(0, 0);
960 polltimeout = 1000*timeout.tv_sec +
961 timeout.tv_nsec/1000000;
963 pollfd.events = POLLRDNORM;
964 n = _poll(&pollfd, 1, polltimeout);
965 #endif /* USE_POLL */
968 Dprint(statp->options & RES_DEBUG, (stdout, ";; timeout\n"));
976 Perror(statp, stderr, "kevent", errno);
979 Perror(statp, stderr, "select", errno);
981 Perror(statp, stderr, "poll", errno);
982 #endif /* USE_POLL */
992 fromlen = sizeof(from);
993 resplen = _recvfrom(s, (char*)ans, anssiz,0,
994 (struct sockaddr *)&from, &fromlen);
996 Perror(statp, stderr, "recvfrom", errno);
1001 if (resplen < HFIXEDSZ) {
1003 * Undersized message.
1005 Dprint(statp->options & RES_DEBUG,
1006 (stdout, ";; undersized: %d\n",
1012 if (hp->id != anhp->id) {
1014 * response from old query, ignore it.
1015 * XXX - potential security hazard could
1018 DprintQ((statp->options & RES_DEBUG) ||
1019 (statp->pfcode & RES_PRF_REPLY),
1020 (stdout, ";; old answer:\n"),
1021 ans, (resplen > anssiz) ? anssiz : resplen);
1024 if (!(statp->options & RES_INSECURE1) &&
1025 !res_ourserver_p(statp, (struct sockaddr *)&from)) {
1027 * response from wrong server? ignore it.
1028 * XXX - potential security hazard could
1031 DprintQ((statp->options & RES_DEBUG) ||
1032 (statp->pfcode & RES_PRF_REPLY),
1033 (stdout, ";; not our server:\n"),
1034 ans, (resplen > anssiz) ? anssiz : resplen);
1037 #ifdef RES_USE_EDNS0
1038 if (anhp->rcode == FORMERR && (statp->options & RES_USE_EDNS0) != 0U) {
1040 * Do not retry if the server do not understand EDNS0.
1041 * The case has to be captured here, as FORMERR packet do not
1042 * carry query section, hence res_queriesmatch() returns 0.
1044 DprintQ(statp->options & RES_DEBUG,
1045 (stdout, "server rejected query with EDNS0:\n"),
1046 ans, (resplen > anssiz) ? anssiz : resplen);
1047 /* record the error */
1048 statp->_flags |= RES_F_EDNS0ERR;
1053 if (!(statp->options & RES_INSECURE2) &&
1054 !res_queriesmatch(buf, buf + buflen,
1055 ans, ans + anssiz)) {
1057 * response contains wrong query? ignore it.
1058 * XXX - potential security hazard could
1061 DprintQ((statp->options & RES_DEBUG) ||
1062 (statp->pfcode & RES_PRF_REPLY),
1063 (stdout, ";; wrong query name:\n"),
1064 ans, (resplen > anssiz) ? anssiz : resplen);
1067 if (anhp->rcode == SERVFAIL ||
1068 anhp->rcode == NOTIMP ||
1069 anhp->rcode == REFUSED) {
1070 DprintQ(statp->options & RES_DEBUG,
1071 (stdout, "server rejected query:\n"),
1072 ans, (resplen > anssiz) ? anssiz : resplen);
1074 /* don't retry if called from dig */
1078 if (!(statp->options & RES_IGNTC) && anhp->tc) {
1080 * To get the rest of answer,
1081 * use TCP with same server.
1083 Dprint(statp->options & RES_DEBUG,
1084 (stdout, ";; truncated answer\n"));
1090 * All is well, or the error is fatal. Signal that the
1091 * next nameserver ought not be tried.
1097 Aerror(const res_state statp, FILE *file, const char *string, int error,
1098 const struct sockaddr *address, int alen)
1101 char hbuf[NI_MAXHOST];
1102 char sbuf[NI_MAXSERV];
1104 if ((statp->options & RES_DEBUG) != 0U) {
1105 if (getnameinfo(address, alen, hbuf, sizeof(hbuf),
1106 sbuf, sizeof(sbuf), niflags)) {
1107 strncpy(hbuf, "?", sizeof(hbuf) - 1);
1108 hbuf[sizeof(hbuf) - 1] = '\0';
1109 strncpy(sbuf, "?", sizeof(sbuf) - 1);
1110 sbuf[sizeof(sbuf) - 1] = '\0';
1112 fprintf(file, "res_send: %s ([%s].%s): %s\n",
1113 string, hbuf, sbuf, strerror(error));
1119 Perror(const res_state statp, FILE *file, const char *string, int error) {
1122 if ((statp->options & RES_DEBUG) != 0U)
1123 fprintf(file, "res_send: %s: %s\n",
1124 string, strerror(error));
1129 sock_eq(struct sockaddr *a, struct sockaddr *b) {
1130 struct sockaddr_in *a4, *b4;
1131 struct sockaddr_in6 *a6, *b6;
1133 if (a->sa_family != b->sa_family)
1135 switch (a->sa_family) {
1137 a4 = (struct sockaddr_in *)a;
1138 b4 = (struct sockaddr_in *)b;
1139 return a4->sin_port == b4->sin_port &&
1140 a4->sin_addr.s_addr == b4->sin_addr.s_addr;
1142 a6 = (struct sockaddr_in6 *)a;
1143 b6 = (struct sockaddr_in6 *)b;
1144 return a6->sin6_port == b6->sin6_port &&
1145 #ifdef HAVE_SIN6_SCOPE_ID
1146 a6->sin6_scope_id == b6->sin6_scope_id &&
1148 IN6_ARE_ADDR_EQUAL(&a6->sin6_addr, &b6->sin6_addr);
1154 #if defined(NEED_PSELECT) && !defined(USE_POLL) && !defined(USE_KQUEUE)
1155 /* XXX needs to move to the porting library. */
1157 pselect(int nfds, void *rfds, void *wfds, void *efds,
1158 struct timespec *tsp, const sigset_t *sigmask)
1160 struct timeval tv, *tvp;
1166 tv = evTimeVal(*tsp);
1170 sigprocmask(SIG_SETMASK, sigmask, &sigs);
1171 n = select(nfds, rfds, wfds, efds, tvp);
1173 sigprocmask(SIG_SETMASK, &sigs, NULL);
1175 *tsp = evTimeSpec(tv);