diff options
Diffstat (limited to 'lib/libc/net/res_send.c')
| -rw-r--r-- | lib/libc/net/res_send.c | 925 |
1 files changed, 0 insertions, 925 deletions
diff --git a/lib/libc/net/res_send.c b/lib/libc/net/res_send.c deleted file mode 100644 index acaf025..0000000 --- a/lib/libc/net/res_send.c +++ /dev/null @@ -1,925 +0,0 @@ -/* - * Copyright (c) 1985, 1989, 1993 - * The Regents of the University of California. All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * 3. All advertising materials mentioning features or use of this software - * must display the following acknowledgement: - * This product includes software developed by the University of - * California, Berkeley and its contributors. - * 4. Neither the name of the University nor the names of its contributors - * may be used to endorse or promote products derived from this software - * without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND - * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE - * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY - * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF - * SUCH DAMAGE. - */ - -/* - * Portions Copyright (c) 1993 by Digital Equipment Corporation. - * - * Permission to use, copy, modify, and distribute this software for any - * purpose with or without fee is hereby granted, provided that the above - * copyright notice and this permission notice appear in all copies, and that - * the name of Digital Equipment Corporation not be used in advertising or - * publicity pertaining to distribution of the document or software without - * specific, written prior permission. - * - * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL - * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES - * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT - * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL - * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR - * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS - * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS - * SOFTWARE. - */ - -/* - * Portions Copyright (c) 1996 by Internet Software Consortium. - * - * Permission to use, copy, modify, and distribute this software for any - * purpose with or without fee is hereby granted, provided that the above - * copyright notice and this permission notice appear in all copies. - * - * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS - * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES - * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE - * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL - * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR - * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS - * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS - * SOFTWARE. - */ - -#if defined(LIBC_SCCS) && !defined(lint) -static char sccsid[] = "@(#)res_send.c 8.1 (Berkeley) 6/4/93"; -static char orig_rcsid[] = "From: Id: res_send.c,v 8.20 1998/04/06 23:27:51 halley Exp $"; -#endif /* LIBC_SCCS and not lint */ -#include <sys/cdefs.h> -__FBSDID("$FreeBSD$"); - -/* - * Send query to name server and wait for reply. - */ - -#include "namespace.h" -#include <sys/types.h> -#include <sys/event.h> -#include <sys/param.h> -#include <sys/time.h> -#include <sys/socket.h> -#include <sys/uio.h> - -#include <netinet/in.h> -#include <arpa/nameser.h> -#include <arpa/inet.h> - -#include <errno.h> -#include <netdb.h> -#include <resolv.h> -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <unistd.h> -#include "un-namespace.h" - -#include "res_config.h" -#include "res_send_private.h" - - -#define s ___res_send_private()->s -#define connected ___res_send_private()->connected -#define vc ___res_send_private()->vc -#define af ___res_send_private()->af -#define Qhook ___res_send_private()->Qhook -#define Rhook ___res_send_private()->Rhook - -#define CAN_RECONNECT 1 - -#ifndef DEBUG -# define Dprint(cond, args) /*empty*/ -# define DprintQ(cond, args, query, size) /*empty*/ -# define Aerror(file, string, error, address) /*empty*/ -# define Perror(file, string, error) /*empty*/ -#else -# define Dprint(cond, args) if (cond) {fprintf args;} else {} -# define DprintQ(cond, args, query, size) if (cond) {\ - fprintf args;\ - __fp_nquery(query, size, stdout);\ - } else {} -static void Aerror(FILE *, char *, int, struct sockaddr *); -static void Perror(FILE *, char *, int); - - static void - Aerror(file, string, error, address) - FILE *file; - char *string; - int error; - struct sockaddr *address; - { - int save = errno; - - if (_res.options & RES_DEBUG) { - char abuf[NI_MAXHOST]; - char pbuf[NI_MAXSERV]; - - if (getnameinfo(address, address->sa_len, abuf, sizeof(abuf), - pbuf, sizeof(pbuf), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { - strncpy(abuf, "?", sizeof(abuf)); - strncpy(pbuf, "?", sizeof(pbuf)); - } - fprintf(file, "res_send: %s ([%s].%s): %s\n", - string, abuf, pbuf, strerror(error)); - } - errno = save; - } - static void - Perror(file, string, error) - FILE *file; - char *string; - int error; - { - int save = errno; - - if (_res.options & RES_DEBUG) { - fprintf(file, "res_send: %s: %s\n", - string, strerror(error)); - } - errno = save; - } -#endif - -static struct sockaddr * get_nsaddr(size_t); - -/* - * pick appropriate nsaddr_list for use. see res_init() for initialization. - */ -static struct sockaddr * -get_nsaddr(n) - size_t n; -{ - - if (!_res.nsaddr_list[n].sin_family) { - /* - * - _res_ext.nsaddr_list[n] holds an address that is larger - * than struct sockaddr, and - * - user code did not update _res.nsaddr_list[n]. - */ - return (struct sockaddr *)&_res_ext.nsaddr_list[n]; - } else { - /* - * - user code updated _res.nsaddr_list[n], or - * - _res.nsaddr_list[n] has the same content as - * _res_ext.nsaddr_list[n]. - */ - return (struct sockaddr *)&_res.nsaddr_list[n]; - } -} - -/* int - * res_isourserver(ina) - * looks up "ina" in _res.ns_addr_list[] - * returns: - * 0 : not found - * >0 : found - * author: - * paul vixie, 29may94 - */ -int -res_isourserver(inp) - const struct sockaddr_in *inp; -{ - const struct sockaddr_in6 *in6p = (const struct sockaddr_in6 *)inp; - const struct sockaddr_in6 *srv6; - const struct sockaddr_in *srv; - int ns, ret; - - ret = 0; - switch (inp->sin_family) { - case AF_INET6: - for (ns = 0; ns < _res.nscount; ns++) { - srv6 = (struct sockaddr_in6 *)get_nsaddr(ns); - if (srv6->sin6_family == in6p->sin6_family && - srv6->sin6_port == in6p->sin6_port && - srv6->sin6_scope_id == in6p->sin6_scope_id && - (IN6_IS_ADDR_UNSPECIFIED(&srv6->sin6_addr) || - IN6_ARE_ADDR_EQUAL(&srv6->sin6_addr, - &in6p->sin6_addr))) { - ret++; - break; - } - } - break; - case AF_INET: - for (ns = 0; ns < _res.nscount; ns++) { - srv = (struct sockaddr_in *)get_nsaddr(ns); - if (srv->sin_family == inp->sin_family && - srv->sin_port == inp->sin_port && - (srv->sin_addr.s_addr == INADDR_ANY || - srv->sin_addr.s_addr == inp->sin_addr.s_addr)) { - ret++; - break; - } - } - break; - } - return (ret); -} - -/* int - * res_nameinquery(name, type, class, buf, eom) - * look for (name,type,class) in the query section of packet (buf,eom) - * requires: - * buf + HFIXEDSZ <= eom - * returns: - * -1 : format error - * 0 : not found - * >0 : found - * author: - * paul vixie, 29may94 - */ -int -res_nameinquery(name, type, class, buf, eom) - const char *name; - int type, class; - const u_char *buf, *eom; -{ - const u_char *cp = buf + HFIXEDSZ; - int qdcount = ntohs(((HEADER*)buf)->qdcount); - - while (qdcount-- > 0) { - char tname[MAXDNAME+1]; - int n, ttype, tclass; - - n = dn_expand(buf, eom, cp, tname, sizeof tname); - if (n < 0) - return (-1); - cp += n; - if (cp + 2 * INT16SZ > eom) - return (-1); - ttype = ns_get16(cp); cp += INT16SZ; - tclass = ns_get16(cp); cp += INT16SZ; - if (ttype == type && - tclass == class && - strcasecmp(tname, name) == 0) - return (1); - } - return (0); -} - -/* int - * res_queriesmatch(buf1, eom1, buf2, eom2) - * is there a 1:1 mapping of (name,type,class) - * in (buf1,eom1) and (buf2,eom2)? - * returns: - * -1 : format error - * 0 : not a 1:1 mapping - * >0 : is a 1:1 mapping - * author: - * paul vixie, 29may94 - */ -int -res_queriesmatch(buf1, eom1, buf2, eom2) - const u_char *buf1, *eom1; - const u_char *buf2, *eom2; -{ - const u_char *cp = buf1 + HFIXEDSZ; - int qdcount = ntohs(((HEADER*)buf1)->qdcount); - - if (buf1 + HFIXEDSZ > eom1 || buf2 + HFIXEDSZ > eom2) - return (-1); - - /* - * Only header section present in replies to - * dynamic update packets. - */ - if ( (((HEADER *)buf1)->opcode == ns_o_update) && - (((HEADER *)buf2)->opcode == ns_o_update) ) - return (1); - - if (qdcount != ntohs(((HEADER*)buf2)->qdcount)) - return (0); - while (qdcount-- > 0) { - char tname[MAXDNAME+1]; - int n, ttype, tclass; - - n = dn_expand(buf1, eom1, cp, tname, sizeof tname); - if (n < 0) - return (-1); - cp += n; - if (cp + 2 * INT16SZ > eom1) - return (-1); - ttype = ns_get16(cp); cp += INT16SZ; - tclass = ns_get16(cp); cp += INT16SZ; - if (!res_nameinquery(tname, ttype, tclass, buf2, eom2)) - return (0); - } - return (1); -} - -int -res_send(buf, buflen, ans, anssiz) - const u_char *buf; - int buflen; - u_char *ans; - int anssiz; -{ - HEADER *hp = (HEADER *) buf; - HEADER *anhp = (HEADER *) ans; - int gotsomewhere, connreset, terrno, try, v_circuit, resplen, ns, n; - int kq; - u_int badns; /* XXX NSMAX can't exceed #/bits in this variable */ - - if ((_res.options & RES_INIT) == 0 && res_init() == -1) { - /* errno should have been set by res_init() in this case. */ - return (-1); - } - if (anssiz < HFIXEDSZ) { - errno = EINVAL; - return (-1); - } - DprintQ((_res.options & RES_DEBUG) || (_res.pfcode & RES_PRF_QUERY), - (stdout, ";; res_send()\n"), buf, buflen); - v_circuit = (_res.options & RES_USEVC) || buflen > PACKETSZ; - gotsomewhere = 0; - connreset = 0; - terrno = ETIMEDOUT; - badns = 0; - - if ((kq = kqueue()) < 0) { - Perror(stderr, "kqueue", errno); - return (-1); - } - - /* - * Send request, RETRY times, or until successful - */ - for (try = 0; try < _res.retry; try++) { - for (ns = 0; ns < _res.nscount; ns++) { - char abuf[NI_MAXHOST]; - struct sockaddr *nsap = get_nsaddr(ns); - socklen_t salen; - - if (nsap->sa_len) - salen = nsap->sa_len; - else if (nsap->sa_family == AF_INET6) - salen = sizeof(struct sockaddr_in6); - else if (nsap->sa_family == AF_INET) - salen = sizeof(struct sockaddr_in); - else - salen = 0; /*unknown, die on connect*/ - - same_ns: - if (badns & (1 << ns)) { - res_close(); - goto next_ns; - } - - if (Qhook) { - int done = 0, loops = 0; - - do { - res_sendhookact act; - - act = (*Qhook)(&nsap, - &buf, &buflen, - ans, anssiz, &resplen); - switch (act) { - case res_goahead: - done = 1; - break; - case res_nextns: - res_close(); - goto next_ns; - case res_done: - _close(kq); - return (resplen); - case res_modified: - /* give the hook another try */ - if (++loops < 42) /*doug adams*/ - break; - /*FALLTHROUGH*/ - case res_error: - /*FALLTHROUGH*/ - default: - _close(kq); - return (-1); - } - } while (!done); - } - - Dprint((_res.options & RES_DEBUG) && - getnameinfo(nsap, salen, abuf, sizeof(abuf), - NULL, 0, NI_NUMERICHOST) == 0, - (stdout, ";; Querying server (# %d) address = %s\n", - ns + 1, abuf)); - - if (v_circuit) { - int truncated; - struct iovec iov[2]; - u_short len; - u_char *cp; - - /* - * Use virtual circuit; - * at most one attempt per server. - */ - try = _res.retry; - truncated = 0; - if (s < 0 || !vc || hp->opcode == ns_o_update || - af != nsap->sa_family) { - if (s >= 0) - res_close(); - - af = nsap->sa_family; - s = _socket(af, SOCK_STREAM, 0); - if (s < 0) { - terrno = errno; - Perror(stderr, "socket(vc)", errno); - badns |= (1 << ns); - res_close(); - goto next_ns; - } - errno = 0; - if (_connect(s, nsap, salen) < 0) { - terrno = errno; - Aerror(stderr, "connect/vc", - errno, nsap); - badns |= (1 << ns); - res_close(); - goto next_ns; - } - vc = 1; - } - /* - * Send length & message - */ - putshort((u_short)buflen, (u_char*)&len); - iov[0].iov_base = (caddr_t)&len; - iov[0].iov_len = INT16SZ; - iov[1].iov_base = (caddr_t)buf; - iov[1].iov_len = buflen; - if (_writev(s, iov, 2) != (INT16SZ + buflen)) { - terrno = errno; - Perror(stderr, "write failed", errno); - badns |= (1 << ns); - res_close(); - goto next_ns; - } - /* - * Receive length & response - */ -read_len: - cp = ans; - len = INT16SZ; - while ((n = _read(s, (char *)cp, (int)len)) > 0) { - cp += n; - if ((len -= n) <= 0) - break; - } - if (n <= 0) { - terrno = errno; - Perror(stderr, "read failed", errno); - res_close(); - /* - * A long running process might get its TCP - * connection reset if the remote server was - * restarted. Requery the server instead of - * trying a new one. When there is only one - * server, this means that a query might work - * instead of failing. We only allow one reset - * per query to prevent looping. - */ - if (terrno == ECONNRESET && !connreset) { - connreset = 1; - res_close(); - goto same_ns; - } - res_close(); - goto next_ns; - } - resplen = ns_get16(ans); - if (resplen > anssiz) { - Dprint(_res.options & RES_DEBUG, - (stdout, ";; response truncated\n") - ); - truncated = 1; - len = anssiz; - } else - len = resplen; - if (len < HFIXEDSZ) { - /* - * Undersized message. - */ - Dprint(_res.options & RES_DEBUG, - (stdout, ";; undersized: %d\n", len)); - terrno = EMSGSIZE; - badns |= (1 << ns); - res_close(); - goto next_ns; - } - cp = ans; - while (len != 0 && - (n = _read(s, (char *)cp, (int)len)) > 0) { - cp += n; - len -= n; - } - if (n <= 0) { - terrno = errno; - Perror(stderr, "read(vc)", errno); - res_close(); - goto next_ns; - } - if (truncated) { - /* - * Flush rest of answer - * so connection stays in synch. - */ - anhp->tc = 1; - len = resplen - anssiz; - while (len != 0) { - char junk[PACKETSZ]; - - n = (len > sizeof(junk) - ? sizeof(junk) - : len); - if ((n = _read(s, junk, n)) > 0) - len -= n; - else - break; - } - } - /* - * The calling applicating has bailed out of - * a previous call and failed to arrange to have - * the circuit closed or the server has got - * itself confused. Anyway drop the packet and - * wait for the correct one. - */ - if (hp->id != anhp->id) { - DprintQ((_res.options & RES_DEBUG) || - (_res.pfcode & RES_PRF_REPLY), - (stdout, ";; old answer (unexpected):\n"), - ans, (resplen>anssiz)?anssiz:resplen); - goto read_len; - } - } else { - /* - * Use datagrams. - */ - struct kevent kv; - struct timespec ts; - struct timeval timeout, ctv; - struct sockaddr_storage from; - socklen_t fromlen; - - if (s < 0 || vc || af != nsap->sa_family) { - if (vc) - res_close(); - af = nsap->sa_family; - s = _socket(af, SOCK_DGRAM, 0); - if (s < 0) { -#ifndef CAN_RECONNECT - bad_dg_sock: -#endif - terrno = errno; - Perror(stderr, "socket(dg)", errno); - badns |= (1 << ns); - res_close(); - goto next_ns; - } - connected = 0; - } -#ifndef CANNOT_CONNECT_DGRAM - /* - * On a 4.3BSD+ machine (client and server, - * actually), sending to a nameserver datagram - * port with no nameserver will cause an - * ICMP port unreachable message to be returned. - * If our datagram socket is "connected" to the - * server, we get an ECONNREFUSED error on the next - * socket operation, and select returns if the - * error message is received. We can thus detect - * the absence of a nameserver without timing out. - * If we have sent queries to at least two servers, - * however, we don't want to remain connected, - * as we wish to receive answers from the first - * server to respond. - * - * When the option "insecure1" is specified, we'd - * rather expect to see responses from an "unknown" - * address. In order to let the kernel accept such - * responses, do not connect the socket here. - * XXX: or do we need an explicit option to disable - * connecting? - */ - if (!(_res.options & RES_INSECURE1) && - (_res.nscount == 1 || (try == 0 && ns == 0))) { - /* - * Connect only if we are sure we won't - * receive a response from another server. - */ - if (!connected) { - if (_connect(s, nsap, salen) < 0) { - Aerror(stderr, - "connect(dg)", - errno, nsap); - badns |= (1 << ns); - res_close(); - goto next_ns; - } - connected = 1; - } - if (send(s, (char*)buf, buflen, 0) != buflen) { - Perror(stderr, "send", errno); - badns |= (1 << ns); - res_close(); - goto next_ns; - } - } else { - /* - * Disconnect if we want to listen - * for responses from more than one server. - */ - if (connected) { -#ifdef CAN_RECONNECT - /* XXX: any errornous address */ - struct sockaddr_in no_addr; - - no_addr.sin_family = AF_INET; - no_addr.sin_addr.s_addr = INADDR_ANY; - no_addr.sin_port = 0; - (void) _connect(s, - (struct sockaddr *) - &no_addr, - sizeof no_addr); -#else - int s1 = _socket(af, SOCK_DGRAM,0); - if (s1 < 0) - goto bad_dg_sock; - (void)_dup2(s1, s); - (void)_close(s1); - Dprint(_res.options & RES_DEBUG, - (stdout, ";; new DG socket\n")) -#endif /* CAN_RECONNECT */ - connected = 0; - errno = 0; - } -#endif /* !CANNOT_CONNECT_DGRAM */ - if (_sendto(s, (char*)buf, buflen, 0, - nsap, salen) != buflen) { - Aerror(stderr, "sendto", errno, nsap); - badns |= (1 << ns); - res_close(); - goto next_ns; - } -#ifndef CANNOT_CONNECT_DGRAM - } -#endif /* !CANNOT_CONNECT_DGRAM */ - - /* - * Wait for reply - */ - - timeout.tv_sec = (_res.retrans << try); - if (try > 0) - timeout.tv_sec /= _res.nscount; - if ((long) timeout.tv_sec <= 0) - timeout.tv_sec = 1; - timeout.tv_usec = 0; - TIMEVAL_TO_TIMESPEC(&timeout, &ts); - (void) gettimeofday(&ctv, NULL); - timeradd(&timeout, &ctv, &timeout); - wait: - if (s < 0) { - Perror(stderr, "s out-of-bounds", EMFILE); - res_close(); - goto next_ns; - } - - EV_SET(&kv, s, EVFILT_READ, EV_ADD | EV_ONESHOT, 0,0,0); - - n = _kevent(kq, &kv, 1, &kv, 1, &ts); - if (n < 0) { - if (errno == EINTR) { - (void) gettimeofday(&ctv, NULL); - if (timercmp(&ctv, &timeout, <)) { - timersub(&timeout, &ctv, &ctv); - TIMEVAL_TO_TIMESPEC(&ctv, &ts); - goto wait; - } - } - Perror(stderr, "kevent", errno); - res_close(); - goto next_ns; - } - - if (n == 0) { - /* - * timeout - */ - Dprint(_res.options & RES_DEBUG, - (stdout, ";; timeout\n")); - gotsomewhere = 1; - res_close(); - goto next_ns; - } - errno = 0; - fromlen = sizeof(from); - resplen = _recvfrom(s, (char*)ans, anssiz, 0, - (struct sockaddr *)&from, &fromlen); - if (resplen <= 0) { - Perror(stderr, "recvfrom", errno); - res_close(); - goto next_ns; - } - gotsomewhere = 1; - if (resplen < HFIXEDSZ) { - /* - * Undersized message. - */ - Dprint(_res.options & RES_DEBUG, - (stdout, ";; undersized: %d\n", - resplen)); - terrno = EMSGSIZE; - badns |= (1 << ns); - res_close(); - goto next_ns; - } - if (hp->id != anhp->id) { - /* - * response from old query, ignore it. - * XXX - potential security hazard could - * be detected here. - */ - DprintQ((_res.options & RES_DEBUG) || - (_res.pfcode & RES_PRF_REPLY), - (stdout, ";; old answer:\n"), - ans, (resplen>anssiz)?anssiz:resplen); - goto wait; - } -#ifdef CHECK_SRVR_ADDR - if (!(_res.options & RES_INSECURE1) && - !res_isourserver((struct sockaddr_in *)&from)) { - /* - * response from wrong server? ignore it. - * XXX - potential security hazard could - * be detected here. - */ - DprintQ((_res.options & RES_DEBUG) || - (_res.pfcode & RES_PRF_REPLY), - (stdout, ";; not our server:\n"), - ans, (resplen>anssiz)?anssiz:resplen); - goto wait; - } -#endif - if (!(_res.options & RES_INSECURE2) && - !res_queriesmatch(buf, buf + buflen, - ans, ans + anssiz)) { - /* - * response contains wrong query? ignore it. - * XXX - potential security hazard could - * be detected here. - */ - DprintQ((_res.options & RES_DEBUG) || - (_res.pfcode & RES_PRF_REPLY), - (stdout, ";; wrong query name:\n"), - ans, (resplen>anssiz)?anssiz:resplen); - goto wait; - } - if (anhp->rcode == SERVFAIL || - anhp->rcode == NOTIMP || - anhp->rcode == REFUSED) { - DprintQ(_res.options & RES_DEBUG, - (stdout, "server rejected query:\n"), - ans, (resplen>anssiz)?anssiz:resplen); - badns |= (1 << ns); - res_close(); - /* don't retry if called from dig */ - if (!_res.pfcode) - goto next_ns; - } - if (!(_res.options & RES_IGNTC) && anhp->tc) { - /* - * get rest of answer; - * use TCP with same server. - */ - Dprint(_res.options & RES_DEBUG, - (stdout, ";; truncated answer\n")); - v_circuit = 1; - res_close(); - goto same_ns; - } - } /*if vc/dg*/ - Dprint((_res.options & RES_DEBUG) || - ((_res.pfcode & RES_PRF_REPLY) && - (_res.pfcode & RES_PRF_HEAD1)), - (stdout, ";; got answer:\n")); - DprintQ((_res.options & RES_DEBUG) || - (_res.pfcode & RES_PRF_REPLY), - (stdout, "%.*s", 0, ""), - ans, (resplen>anssiz)?anssiz:resplen); - /* - * If using virtual circuits, we assume that the first server - * is preferred over the rest (i.e. it is on the local - * machine) and only keep that one open. - * If we have temporarily opened a virtual circuit, - * or if we haven't been asked to keep a socket open, - * close the socket. - */ - if ((v_circuit && (!(_res.options & RES_USEVC) || ns != 0)) || - !(_res.options & RES_STAYOPEN)) { - res_close(); - } - if (Rhook) { - int done = 0, loops = 0; - - do { - res_sendhookact act; - - act = (*Rhook)(nsap, - buf, buflen, - ans, anssiz, &resplen); - switch (act) { - case res_goahead: - case res_done: - done = 1; - break; - case res_nextns: - res_close(); - goto next_ns; - case res_modified: - /* give the hook another try */ - if (++loops < 42) /*doug adams*/ - break; - /*FALLTHROUGH*/ - case res_error: - /*FALLTHROUGH*/ - default: - _close(kq); - return (-1); - } - } while (!done); - - } - _close(kq); - return (resplen); - next_ns: ; - } /*foreach ns*/ - } /*foreach retry*/ - res_close(); - _close(kq); - if (!v_circuit) { - if (!gotsomewhere) - errno = ECONNREFUSED; /* no nameservers found */ - else - errno = ETIMEDOUT; /* no answer obtained */ - } else - errno = terrno; - return (-1); -} - -/* - * This routine is for closing the socket if a virtual circuit is used and - * the program wants to close it. This provides support for endhostent() - * which expects to close the socket. - * - * This routine is not expected to be user visible. - */ -void -res_close() -{ - if (s >= 0) { - (void)_close(s); - s = -1; - connected = 0; - vc = 0; - af = 0; - } -} - -/* - * Weak aliases for applications that use certain private entry points, - * and fail to include <resolv.h>. - */ -#undef res_close -__weak_reference(__res_close, _res_close); -#undef res_send -__weak_reference(__res_send, res_send); |
