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authorRoland McGrath <roland@gnu.org>1995-02-18 01:27:10 +0000
committerRoland McGrath <roland@gnu.org>1995-02-18 01:27:10 +0000
commit28f540f45bbacd939bfd07f213bcad2bf730b1bf (patch)
tree15f07c4c43d635959c6afee96bde71fb1b3614ee /resolv/gethnamaddr.c
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initial import
Diffstat (limited to 'resolv/gethnamaddr.c')
-rw-r--r--resolv/gethnamaddr.c736
1 files changed, 736 insertions, 0 deletions
diff --git a/resolv/gethnamaddr.c b/resolv/gethnamaddr.c
new file mode 100644
index 0000000..55a3fb0
--- /dev/null
+++ b/resolv/gethnamaddr.c
@@ -0,0 +1,736 @@
+/*
+ * ++Copyright++ 1985, 1988, 1993
+ * -
+ * Copyright (c) 1985, 1988, 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.
+ * -
+ * --Copyright--
+ */
+
+#if defined(LIBC_SCCS) && !defined(lint)
+static char sccsid[] = "@(#)gethostnamadr.c 8.1 (Berkeley) 6/4/93";
+static char rcsid[] = "$Id$";
+#endif /* LIBC_SCCS and not lint */
+
+#include <sys/param.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <arpa/nameser.h>
+
+#include <stdio.h>
+#include <netdb.h>
+#include <resolv.h>
+#include <ctype.h>
+#include <errno.h>
+#include <syslog.h>
+
+#ifndef LOG_AUTH
+# define LOG_AUTH 0
+#endif
+
+#define MULTI_PTRS_ARE_ALIASES 1 /* XXX - experimental */
+
+#if defined(BSD) && (BSD >= 199103)
+# include <string.h>
+#else
+# include "../conf/portability.h"
+#endif
+#if defined(USE_OPTIONS_H)
+# include <../conf/options.h>
+#endif
+
+#define MAXALIASES 35
+#define MAXADDRS 35
+
+static const char AskedForGot[] =
+ "gethostby*.getanswer: asked for \"%s\", got \"%s\"";
+
+static char *h_addr_ptrs[MAXADDRS + 1];
+
+static struct hostent host;
+static char *host_aliases[MAXALIASES];
+static char hostbuf[8*1024];
+static struct in_addr host_addr;
+static FILE *hostf = NULL;
+static int stayopen = 0;
+
+#ifdef RESOLVSORT
+static void addrsort __P((char **, int));
+#endif
+
+#if PACKETSZ > 1024
+#define MAXPACKET PACKETSZ
+#else
+#define MAXPACKET 1024
+#endif
+
+typedef union {
+ HEADER hdr;
+ u_char buf[MAXPACKET];
+} querybuf;
+
+typedef union {
+ int32_t al;
+ char ac;
+} align;
+
+extern int h_errno;
+
+#ifdef DEBUG
+static void
+dprintf(msg, num)
+ char *msg;
+ int num;
+{
+ if (_res.options & RES_DEBUG) {
+ int save = errno;
+
+ printf(msg, num);
+ errno = save;
+ }
+}
+#else
+# define dprintf(msg, num) /*nada*/
+#endif
+
+static struct hostent *
+getanswer(answer, anslen, qname, qclass, qtype)
+ const querybuf *answer;
+ int anslen;
+ const char *qname;
+ int qclass, qtype;
+{
+ register const HEADER *hp;
+ register const u_char *cp;
+ register int n;
+ const u_char *eom;
+ char *bp, **ap, **hap;
+ int type, class, buflen, ancount, qdcount;
+ int haveanswer, had_error;
+ int toobig = 0;
+ char tbuf[MAXDNAME+1];
+
+ host.h_name = NULL;
+ eom = answer->buf + anslen;
+ /*
+ * find first satisfactory answer
+ */
+ hp = &answer->hdr;
+ ancount = ntohs(hp->ancount);
+ qdcount = ntohs(hp->qdcount);
+ bp = hostbuf;
+ buflen = sizeof hostbuf;
+ cp = answer->buf + HFIXEDSZ;
+ if (qdcount != 1) {
+ h_errno = NO_RECOVERY;
+ return (NULL);
+ }
+ if ((n = dn_expand(answer->buf, eom, cp, bp, buflen)) < 0) {
+ h_errno = NO_RECOVERY;
+ return (NULL);
+ }
+ cp += n + QFIXEDSZ;
+ if (qtype == T_A) {
+ /* res_send() has already verified that the query name is the
+ * same as the one we sent; this just gets the expanded name
+ * (i.e., with the succeeding search-domain tacked on).
+ */
+ n = strlen(bp) + 1; /* for the \0 */
+ host.h_name = bp;
+ bp += n;
+ buflen -= n;
+ /* The qname can be abbreviated, but h_name is now absolute. */
+ qname = host.h_name;
+ }
+ ap = host_aliases;
+ *ap = NULL;
+ host.h_aliases = host_aliases;
+ hap = h_addr_ptrs;
+ *hap = NULL;
+#if BSD >= 43 || defined(h_addr) /* new-style hostent structure */
+ host.h_addr_list = h_addr_ptrs;
+#endif
+ haveanswer = 0;
+ had_error = 0;
+ while (ancount-- > 0 && cp < eom && !had_error) {
+ n = dn_expand(answer->buf, eom, cp, bp, buflen);
+ if (n < 0) {
+ had_error++;
+ continue;
+ }
+ cp += n; /* name */
+ type = _getshort(cp);
+ cp += INT16SZ; /* type */
+ class = _getshort(cp);
+ cp += INT16SZ + INT32SZ; /* class, TTL */
+ n = _getshort(cp);
+ cp += INT16SZ; /* len */
+ if (class != qclass) {
+ /* XXX - debug? syslog? */
+ cp += n;
+ continue; /* XXX - had_error++ ? */
+ }
+ if (qtype == T_A && type == T_CNAME) {
+ if (ap >= &host_aliases[MAXALIASES-1])
+ continue;
+ n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf);
+ if (n < 0) {
+ had_error++;
+ continue;
+ }
+ cp += n;
+ if (host.h_name && strcasecmp(host.h_name, bp) != 0) {
+ syslog(LOG_NOTICE|LOG_AUTH,
+ "gethostby*.getanswer: asked for \"%s\", got CNAME for \"%s\"",
+ host.h_name, bp);
+ continue; /* XXX - had_error++ ? */
+ }
+ /* Store alias. */
+ *ap++ = bp;
+ n = strlen(bp) + 1; /* for the \0 */
+ bp += n;
+ buflen -= n;
+ /* Get canonical name. */
+ n = strlen(tbuf) + 1; /* for the \0 */
+ if (n > buflen) {
+ had_error++;
+ continue;
+ }
+ strcpy(bp, tbuf);
+ host.h_name = bp;
+ bp += n;
+ buflen -= n;
+ continue;
+ }
+ if (type != qtype) {
+ syslog(LOG_NOTICE|LOG_AUTH,
+ "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"",
+ qname, p_class(qclass), p_type(qtype),
+ p_type(type));
+ cp += n;
+ continue; /* XXX - had_error++ ? */
+ }
+ switch (type) {
+ case T_PTR:
+ if (strcasecmp(qname, bp) != 0) {
+ syslog(LOG_NOTICE|LOG_AUTH,
+ AskedForGot, qname, bp);
+ cp += n;
+ continue; /* XXX - had_error++ ? */
+ }
+ n = dn_expand(answer->buf, eom, cp, bp, buflen);
+ if (n < 0) {
+ had_error++;
+ break;
+ }
+#if MULTI_PTRS_ARE_ALIASES
+ cp += n;
+ if (!haveanswer)
+ host.h_name = bp;
+ else if (ap < &host_aliases[MAXALIASES-1])
+ *ap++ = bp;
+ else
+ n = -1;
+ if (n != -1) {
+ n = strlen(bp) + 1; /* for the \0 */
+ bp += n;
+ buflen -= n;
+ }
+ break;
+#else
+ host.h_name = bp;
+ h_errno = NETDB_SUCCESS;
+ return (&host);
+#endif
+ case T_A:
+ if (strcasecmp(host.h_name, bp) != 0) {
+ syslog(LOG_NOTICE|LOG_AUTH,
+ AskedForGot, host.h_name, bp);
+ cp += n;
+ continue; /* XXX - had_error++ ? */
+ }
+ if (haveanswer) {
+ if (n != host.h_length) {
+ cp += n;
+ continue;
+ }
+ } else {
+ register int nn;
+
+ host.h_length = n;
+ host.h_addrtype = (class == C_IN)
+ ? AF_INET
+ : AF_UNSPEC;
+ host.h_name = bp;
+ nn = strlen(bp) + 1; /* for the \0 */
+ bp += nn;
+ buflen -= nn;
+ }
+
+ bp += sizeof(align) - ((u_long)bp % sizeof(align));
+
+ if (bp + n >= &hostbuf[sizeof hostbuf]) {
+ dprintf("size (%d) too big\n", n);
+ had_error++;
+ continue;
+ }
+ if (hap >= &h_addr_ptrs[MAXADDRS-1]) {
+ if (!toobig++)
+ dprintf("Too many addresses (%d)\n",
+ MAXADDRS);
+ cp += n;
+ continue;
+ }
+ bcopy(cp, *hap++ = bp, n);
+ bp += n;
+ cp += n;
+ break;
+ default:
+ dprintf("Impossible condition (type=%d)\n", type);
+ h_errno = NO_RECOVERY;
+ return (NULL);
+ } /*switch*/
+ if (!had_error)
+ haveanswer++;
+ } /*while*/
+ if (haveanswer) {
+ *ap = NULL;
+ *hap = NULL;
+# if defined(RESOLVSORT)
+ /*
+ * Note: we sort even if host can take only one address
+ * in its return structures - should give it the "best"
+ * address in that case, not some random one
+ */
+ if (_res.nsort && haveanswer > 1 &&
+ qclass == C_IN && qtype == T_A)
+ addrsort(h_addr_ptrs, haveanswer);
+# endif /*RESOLVSORT*/
+#if BSD >= 43 || defined(h_addr) /* new-style hostent structure */
+ /* nothing */
+#else
+ host.h_addr = h_addr_ptrs[0];
+#endif /*BSD*/
+ if (!host.h_name) {
+ n = strlen(qname) + 1; /* for the \0 */
+ strcpy(bp, qname);
+ host.h_name = bp;
+ }
+ h_errno = NETDB_SUCCESS;
+ return (&host);
+ } else {
+ h_errno = TRY_AGAIN;
+ return (NULL);
+ }
+}
+
+struct hostent *
+gethostbyname(name)
+ const char *name;
+{
+ querybuf buf;
+ register const char *cp;
+ int n;
+ extern struct hostent *_gethtbyname();
+
+ /*
+ * if there aren't any dots, it could be a user-level alias.
+ * this is also done in res_query() since we are not the only
+ * function that looks up host names.
+ */
+ if (!strchr(name, '.') && (cp = __hostalias(name)))
+ name = cp;
+
+ /*
+ * disallow names consisting only of digits/dots, unless
+ * they end in a dot.
+ */
+ if (isdigit(name[0]))
+ for (cp = name;; ++cp) {
+ if (!*cp) {
+ if (*--cp == '.')
+ break;
+ /*
+ * All-numeric, no dot at the end.
+ * Fake up a hostent as if we'd actually
+ * done a lookup.
+ */
+ if (!inet_aton(name, &host_addr)) {
+ h_errno = HOST_NOT_FOUND;
+ return (NULL);
+ }
+ host.h_name = (char *)name;
+ host.h_aliases = host_aliases;
+ host_aliases[0] = NULL;
+ host.h_addrtype = AF_INET;
+ host.h_length = INT32SZ;
+ h_addr_ptrs[0] = (char *)&host_addr;
+ h_addr_ptrs[1] = NULL;
+#if BSD >= 43 || defined(h_addr) /* new-style hostent structure */
+ host.h_addr_list = h_addr_ptrs;
+#else
+ host.h_addr = h_addr_ptrs[0];
+#endif
+ h_errno = NETDB_SUCCESS;
+ return (&host);
+ }
+ if (!isdigit(*cp) && *cp != '.')
+ break;
+ }
+
+ if ((n = res_search(name, C_IN, T_A, buf.buf, sizeof(buf))) < 0) {
+ dprintf("res_search failed (%d)\n", n);
+ if (errno == ECONNREFUSED)
+ return (_gethtbyname(name));
+ return (NULL);
+ }
+ return (getanswer(&buf, n, name, C_IN, T_A));
+}
+
+struct hostent *
+gethostbyaddr(addr, len, type)
+ const char *addr;
+ int len, type;
+{
+ int n;
+ querybuf buf;
+ register struct hostent *hp;
+ char qbuf[MAXDNAME+1];
+#ifdef SUNSECURITY
+ register struct hostent *rhp;
+ char **haddr;
+ u_long old_options;
+ char hname2[MAXDNAME+1];
+#endif /*SUNSECURITY*/
+ extern struct hostent *_gethtbyaddr();
+
+ if (type != AF_INET) {
+ errno = EAFNOSUPPORT;
+ h_errno = NETDB_INTERNAL;
+ return (NULL);
+ }
+ (void)sprintf(qbuf, "%u.%u.%u.%u.in-addr.arpa",
+ ((unsigned)addr[3] & 0xff),
+ ((unsigned)addr[2] & 0xff),
+ ((unsigned)addr[1] & 0xff),
+ ((unsigned)addr[0] & 0xff));
+ n = res_query(qbuf, C_IN, T_PTR, (u_char *)buf.buf, sizeof buf.buf);
+ if (n < 0) {
+ dprintf("res_query failed (%d)\n", n);
+ if (errno == ECONNREFUSED)
+ return (_gethtbyaddr(addr, len, type));
+ return (NULL);
+ }
+ if (!(hp = getanswer(&buf, n, qbuf, C_IN, T_PTR)))
+ return (NULL); /* h_errno was set by getanswer() */
+#ifdef SUNSECURITY
+ /*
+ * turn off search as the name should be absolute,
+ * 'localhost' should be matched by defnames
+ */
+ strncpy(hname2, hp->h_name, MAXDNAME);
+ hname2[MAXDNAME] = '\0';
+ old_options = _res.options;
+ _res.options &= ~RES_DNSRCH;
+ _res.options |= RES_DEFNAMES;
+ if (!(rhp = gethostbyname(hp->h_name))) {
+ syslog(LOG_NOTICE|LOG_AUTH,
+ "gethostbyaddr: No A record for %s (verifying [%s])",
+ hname2, inet_ntoa(*((struct in_addr *)addr)));
+ _res.options = old_options;
+ h_errno = HOST_NOT_FOUND;
+ return (NULL);
+ }
+ _res.options = old_options;
+ for (haddr = rhp->h_addr_list; *haddr; haddr++)
+ if (!memcmp(*haddr, addr, INADDRSZ))
+ break;
+ if (!*haddr) {
+ syslog(LOG_NOTICE|LOG_AUTH,
+ "gethostbyaddr: A record of %s != PTR record [%s]",
+ hname2, inet_ntoa(*((struct in_addr *)addr)));
+ h_errno = HOST_NOT_FOUND;
+ return (NULL);
+ }
+#endif /*SUNSECURITY*/
+ hp->h_addrtype = type;
+ hp->h_length = len;
+ h_addr_ptrs[0] = (char *)&host_addr;
+ h_addr_ptrs[1] = NULL;
+ host_addr = *(struct in_addr *)addr;
+ h_errno = NETDB_SUCCESS;
+ return (hp);
+}
+
+void
+_sethtent(f)
+ int f;
+{
+ if (!hostf)
+ hostf = fopen(_PATH_HOSTS, "r" );
+ else
+ rewind(hostf);
+ stayopen = f;
+}
+
+void
+_endhtent()
+{
+ if (hostf && !stayopen) {
+ (void) fclose(hostf);
+ hostf = NULL;
+ }
+}
+
+struct hostent *
+_gethtent()
+{
+ char *p;
+ register char *cp, **q;
+
+ if (!hostf && !(hostf = fopen(_PATH_HOSTS, "r" ))) {
+ h_errno = NETDB_INTERNAL;
+ return (NULL);
+ }
+again:
+ if (!(p = fgets(hostbuf, sizeof hostbuf, hostf))) {
+ h_errno = HOST_NOT_FOUND;
+ return (NULL);
+ }
+ if (*p == '#')
+ goto again;
+ if (!(cp = strpbrk(p, "#\n")))
+ goto again;
+ *cp = '\0';
+ if (!(cp = strpbrk(p, " \t")))
+ goto again;
+ *cp++ = '\0';
+ /* THIS STUFF IS INTERNET SPECIFIC */
+ if (!inet_aton(p, &host_addr))
+ goto again;
+ h_addr_ptrs[0] = (char *)&host_addr;
+ h_addr_ptrs[1] = NULL;
+#if BSD >= 43 || defined(h_addr) /* new-style hostent structure */
+ host.h_addr_list = h_addr_ptrs;
+#else
+ host.h_addr = h_addr_ptrs[0];
+#endif
+ host.h_length = INT32SZ;
+ host.h_addrtype = AF_INET;
+ while (*cp == ' ' || *cp == '\t')
+ cp++;
+ host.h_name = cp;
+ q = host.h_aliases = host_aliases;
+ if (cp = strpbrk(cp, " \t"))
+ *cp++ = '\0';
+ while (cp && *cp) {
+ if (*cp == ' ' || *cp == '\t') {
+ cp++;
+ continue;
+ }
+ if (q < &host_aliases[MAXALIASES - 1])
+ *q++ = cp;
+ if (cp = strpbrk(cp, " \t"))
+ *cp++ = '\0';
+ }
+ *q = NULL;
+ h_errno = NETDB_SUCCESS;
+ return (&host);
+}
+
+struct hostent *
+_gethtbyname(name)
+ char *name;
+{
+ register struct hostent *p;
+ register char **cp;
+
+ _sethtent(0);
+ while (p = _gethtent()) {
+ if (strcasecmp(p->h_name, name) == 0)
+ break;
+ for (cp = p->h_aliases; *cp != 0; cp++)
+ if (strcasecmp(*cp, name) == 0)
+ goto found;
+ }
+found:
+ _endhtent();
+ return (p);
+}
+
+struct hostent *
+_gethtbyaddr(addr, len, type)
+ const char *addr;
+ int len, type;
+{
+ register struct hostent *p;
+
+ _sethtent(0);
+ while (p = _gethtent())
+ if (p->h_addrtype == type && !bcmp(p->h_addr, addr, len))
+ break;
+ _endhtent();
+ return (p);
+}
+
+#ifdef RESOLVSORT
+static void
+addrsort(ap, num)
+ char **ap;
+ int num;
+{
+ int i, j;
+ char **p;
+ short aval[MAXADDRS];
+ int needsort = 0;
+
+ p = ap;
+ for (i = 0; i < num; i++, p++) {
+ for (j = 0 ; (unsigned)j < _res.nsort; j++)
+ if (_res.sort_list[j].addr.s_addr ==
+ (((struct in_addr *)(*p))->s_addr & _res.sort_list[j].mask))
+ break;
+ aval[i] = j;
+ if (needsort == 0 && i > 0 && j < aval[i-1])
+ needsort = i;
+ }
+ if (!needsort)
+ return;
+
+ while (needsort < num) {
+ for (j = needsort - 1; j >= 0; j--) {
+ if (aval[j] > aval[j+1]) {
+ char *hp;
+
+ i = aval[j];
+ aval[j] = aval[j+1];
+ aval[j+1] = i;
+
+ hp = ap[j];
+ ap[j] = ap[j+1];
+ ap[j+1] = hp;
+
+ } else
+ break;
+ }
+ needsort++;
+ }
+}
+#endif
+
+#if defined(BSD43_BSD43_NFS) || defined(sun)
+/* some libc's out there are bound internally to these names (UMIPS) */
+void
+ht_sethostent(stayopen)
+ int stayopen;
+{
+ _sethtent(stayopen);
+}
+
+void
+ht_endhostent()
+{
+ _endhtent();
+}
+
+struct hostent *
+ht_gethostbyname(name)
+ char *name;
+{
+ return (_gethtbyname(name));
+}
+
+struct hostent *
+ht_gethostbyaddr(addr, len, type)
+ const char *addr;
+ int len, type;
+{
+ return (_gethtbyaddr(addr, len, type));
+}
+
+struct hostent *
+gethostent()
+{
+ return (_gethtent());
+}
+
+void
+dns_service()
+{
+ return;
+}
+
+#undef dn_skipname
+dn_skipname(comp_dn, eom)
+ const u_char *comp_dn, *eom;
+{
+ return (__dn_skipname(comp_dn, eom));
+}
+#endif /*old-style libc with yp junk in it*/
+
+#ifdef ultrix
+/* more icky libc packaging in ultrix */
+int
+local_hostname_length(hostname)
+ const char *hostname;
+{
+ int len_host, len_domain;
+
+ if (!*_res.defdname)
+ res_init();
+ len_host = strlen(hostname);
+ len_domain = strlen(_res.defdname);
+ if (len_host > len_domain &&
+ !strcasecmp(hostname + len_host - len_domain, _res.defdname) &&
+ hostname[len_host - len_domain - 1] == '.')
+ return (len_host - len_domain - 1);
+ return (0);
+}
+#endif