diff options
| author | darylm503 <darylm503@6f19259b-4bc3-4df7-8a09-765794883524> | 2011-07-30 00:30:44 +0000 |
|---|---|---|
| committer | darylm503 <darylm503@6f19259b-4bc3-4df7-8a09-765794883524> | 2011-07-30 00:30:44 +0000 |
| commit | d7ce700605e1af0e455e31ec11f19ff21d26b525 (patch) | |
| tree | 243b582ac3350e8c6ce6ca96fff13805318fd65c /StdLib/BsdSocketLib/res_send.c | |
| parent | f766dd76fde231ecd4f2e9faf99293e90902cebb (diff) | |
| download | edk2-platforms-d7ce700605e1af0e455e31ec11f19ff21d26b525.tar.xz | |
Add Socket Libraries.
Add Posix functions for porting compatibility.
Fix compliance issues with ISO/IEC 9899:199409
New Functions:
setenv(), fparseln(), GetFileNameFromPath(), rename(),
realpath(), setprogname(), getprogname(), strlcat(), strlcpy(),
strsep(), setitimer(), getitimer(), timegm(), getopt(), basename(),
mkstemp(), ffs(), vsnprintf(), snprintf(), getpass(), usleep(), select(),
writev(), strcasecmp(), getcwd(), chdir(), tcgetpgrp(), getpgrp(), gettimeofday(),
bcopy(),
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@12061 6f19259b-4bc3-4df7-8a09-765794883524
Diffstat (limited to 'StdLib/BsdSocketLib/res_send.c')
| -rw-r--r-- | StdLib/BsdSocketLib/res_send.c | 934 |
1 files changed, 934 insertions, 0 deletions
diff --git a/StdLib/BsdSocketLib/res_send.c b/StdLib/BsdSocketLib/res_send.c new file mode 100644 index 0000000000..82addc9745 --- /dev/null +++ b/StdLib/BsdSocketLib/res_send.c @@ -0,0 +1,934 @@ +/*
+ * Copyright (c) 1985, 1989, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * Portions copyright (c) 1999, 2000
+ * Intel Corporation.
+ * 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, Intel Corporation, and its contributors.
+ *
+ * 4. Neither the name of University, Intel Corporation, or their respective
+ * 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, INTEL CORPORATION 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,
+ * INTEL CORPORATION 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 $";
+static char rcsid[] = "$Id: res_send.c,v 1.1.1.1 2003/11/19 01:51:39 kyu3 Exp $";
+#endif /* LIBC_SCCS and not lint */
+
+/*
+ * Send query to name server and wait for reply.
+ */
+
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/select.h>
+#include <sys/socket.h>
+#include <sys/time.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 "res_config.h"
+
+#ifndef _ORG_FREEBSD_
+#define NOPOLL
+#endif
+
+#ifdef NOPOLL /* libc_r doesn't wrap poll yet() */
+static int use_poll = 0;
+#else
+#include <poll.h>
+static int use_poll = 1; /* adapt to poll() syscall availability */
+ /* 0 = not present, 1 = try it, 2 = exists */
+#endif
+
+static int s = -1; /* socket used for communications */
+static int connected = 0; /* is the socket connected */
+static int vc = 0; /* is the socket a virtual circuit? */
+static res_send_qhook Qhook = NULL;
+static res_send_rhook Rhook = NULL;
+
+
+#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 *file,
+ char *string,
+ int error,
+ struct sockaddr_in address
+ )
+{
+ int save = errno;
+
+ if (_res.options & RES_DEBUG) {
+ fprintf(file, "res_send: %s ([%s].%u): %s\n",
+ string,
+ inet_ntoa(address.sin_addr),
+ ntohs(address.sin_port),
+ strerror(error));
+ }
+ errno = save;
+}
+
+
+static void
+Perror(
+ 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
+
+void
+res_send_setqhook(
+ res_send_qhook hook
+ )
+{
+
+ Qhook = hook;
+}
+
+void
+res_send_setrhook(
+ res_send_rhook hook
+ )
+{
+
+ Rhook = hook;
+}
+
+/* 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(
+ const struct sockaddr_in *inp
+ )
+{
+ struct sockaddr_in ina;
+ int ns, ret;
+
+ ina = *inp;
+ ret = 0;
+ for (ns = 0; ns < _res.nscount; ns++) {
+ const struct sockaddr_in *srv = &_res.nsaddr_list[ns];
+
+ if (srv->sin_family == ina.sin_family &&
+ srv->sin_port == ina.sin_port &&
+ (srv->sin_addr.s_addr == INADDR_ANY ||
+ srv->sin_addr.s_addr == ina.sin_addr.s_addr)) {
+ ret++;
+ 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(
+ const char *name,
+ int type,
+ int class,
+ const u_char *buf,
+ const u_char *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(
+ const u_char *buf1,
+ const u_char *eom1,
+ const u_char *buf2,
+ const u_char *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(
+ 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;
+ ssize_t n;
+ u_int32_t 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;
+
+ /*
+ * Send request, RETRY times, or until successful
+ */
+ for (try = 0; try < _res.retry; try++) {
+ for (ns = 0; ns < _res.nscount; ns++) {
+ struct sockaddr_in *nsap = &_res.nsaddr_list[ns];
+ 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:
+ return (resplen);
+ case res_modified:
+ /* give the hook another try */
+ if (++loops < 42) /*doug adams*/
+ break;
+ /*FALLTHROUGH*/
+ case res_error:
+ /*FALLTHROUGH*/
+ default:
+ return (-1);
+ }
+ } while (!done);
+ }
+
+ Dprint(_res.options & RES_DEBUG,
+ (stdout, ";; Querying server (# %d) address = %s\n",
+ ns + 1, inet_ntoa(nsap->sin_addr)));
+
+ 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) {
+ if (s >= 0)
+ res_close();
+
+ s = socket(PF_INET, SOCK_STREAM, 0);
+ if (s < 0) {
+ terrno = errno;
+ Perror(stderr, "socket(vc)", errno);
+ return (-1);
+ }
+ errno = 0;
+ nsap->sin_len = sizeof ( *nsap );
+ if (connect(s, (struct sockaddr *)nsap,
+ sizeof *nsap) < 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;
+ len = (u_short)( len - n );
+ if (len <= 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 = (ushort)anssiz;
+ } else
+ len = (ushort)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 = (u_short)( 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 = (ushort)( resplen - anssiz );
+ while (len != 0) {
+ char junk[PACKETSZ];
+
+ n = (len > sizeof(junk)
+ ? sizeof(junk)
+ : len);
+ if ((n = read(s, junk, n)) > 0)
+ len = (u_short)( 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.
+ */
+#ifndef NOPOLL
+ struct pollfd pfd;
+ int msec;
+#endif
+ struct timeval timeout;
+ fd_set dsmask, *dsmaskp;
+ int dsmasklen;
+ struct sockaddr_in from;
+ int fromlen;
+
+ if ((s < 0) || vc) {
+ if (vc)
+ res_close();
+ s = socket(PF_INET, SOCK_DGRAM, 0);
+ if (s < 0) {
+#ifndef CAN_RECONNECT
+ bad_dg_sock:
+#endif
+ terrno = errno;
+ Perror(stderr, "socket(dg)", errno);
+ return (-1);
+ }
+ 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.
+ */
+ if (_res.nscount == 1 || (try == 0 && ns == 0)) {
+ /*
+ * Connect only if we are sure we won't
+ * receive a response from another server.
+ */
+ if (!connected) {
+ nsap->sin_len = sizeof ( *nsap );
+ if (connect(s, (struct sockaddr *)nsap,
+ sizeof *nsap
+ ) < 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
+ 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(PF_INET, 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,
+ (struct sockaddr *)nsap,
+ sizeof *nsap)
+ != 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
+ */
+#ifndef NOPOLL
+ othersyscall:
+ if (use_poll) {
+ msec = (_res.retrans << try) * 1000;
+ if (try > 0)
+ msec /= _res.nscount;
+ if (msec <= 0)
+ msec = 1000;
+ } else {
+#endif
+ 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;
+#ifndef NOPOLL
+ }
+#endif
+ wait:
+ if (s < 0) {
+ Perror(stderr, "s out-of-bounds", EMFILE);
+ res_close();
+ goto next_ns;
+ }
+#ifndef NOPOLL
+ if (use_poll) {
+ struct sigaction sa, osa;
+ int sigsys_installed = 0;
+
+ pfd.fd = s;
+ pfd.events = POLLIN;
+ if (use_poll == 1) {
+ bzero(&sa, sizeof(sa));
+ sa.sa_handler = SIG_IGN;
+ if (sigaction(SIGSYS, &sa, &osa) >= 0)
+ sigsys_installed = 1;
+ }
+ n = poll(&pfd, 1, msec);
+ if (sigsys_installed == 1) {
+ int oerrno = errno;
+ sigaction(SIGSYS, &osa, NULL);
+ errno = oerrno;
+ }
+ /* XXX why does nosys() return EINVAL? */
+ if (n < 0 && (errno == ENOSYS ||
+ errno == EINVAL)) {
+ use_poll = 0;
+ goto othersyscall;
+ } else if (use_poll == 1)
+ use_poll = 2;
+ if (n < 0) {
+ if (errno == EINTR)
+ goto wait;
+ Perror(stderr, "poll", errno);
+ res_close();
+ goto next_ns;
+ }
+ } else {
+#endif
+ dsmasklen = howmany(s + 1, NFDBITS) *
+ sizeof(fd_mask);
+ if (dsmasklen > sizeof(fd_set)) {
+ dsmaskp = (fd_set *)malloc(dsmasklen);
+ if (dsmaskp == NULL) {
+ res_close();
+ goto next_ns;
+ }
+ } else
+ dsmaskp = &dsmask;
+ /* only zero what we need */
+ memset((char *)dsmaskp, 0, dsmasklen);
+ FD_SET(s, dsmaskp);
+ n = select(s + 1, dsmaskp, (fd_set *)NULL,
+ (fd_set *)NULL, &timeout);
+ if (dsmaskp != &dsmask)
+ free(dsmaskp);
+ if (n < 0) {
+ if (errno == EINTR)
+ goto wait;
+ Perror(stderr, "select", errno);
+ res_close();
+ goto next_ns;
+ }
+#ifndef NOPOLL
+ }
+#endif
+
+ if (n == 0) {
+ /*
+ * timeout
+ */
+ Dprint(_res.options & RES_DEBUG,
+ (stdout, ";; timeout\n"));
+ gotsomewhere = 1;
+ res_close();
+ goto next_ns;
+ }
+ errno = 0;
+ fromlen = sizeof(struct sockaddr_in);
+ resplen = (int)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(&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, ""),
+ 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:
+ return (-1);
+ }
+ } while (!done);
+
+ }
+ return (resplen);
+ next_ns: ;
+ } /*foreach ns*/
+ } /*foreach retry*/
+ res_close();
+ 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;
+ }
+}
|