5500fdcd4f
libc/db, libc/gen/crypt.* and libtelnet. All affected files except 3 unimportant ones have already left the vendor branch.
304 lines
9.3 KiB
C
304 lines
9.3 KiB
C
/*-
|
|
* Copyright (c) 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[] = "@(#)res_query.c 8.1 (Berkeley) 6/4/93";
|
|
static char rcsid[] = "$Id: res_query.c,v 1.1 1993/06/01 09:42:14 vixie Exp vixie $";
|
|
#endif /* LIBC_SCCS and not lint */
|
|
|
|
#include <sys/param.h>
|
|
#include <netinet/in.h>
|
|
#include <arpa/inet.h>
|
|
#include <arpa/nameser.h>
|
|
#include <netdb.h>
|
|
#include <resolv.h>
|
|
#include <stdio.h>
|
|
#include <ctype.h>
|
|
#include <errno.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
|
|
#if PACKETSZ > 1024
|
|
#define MAXPACKET PACKETSZ
|
|
#else
|
|
#define MAXPACKET 1024
|
|
#endif
|
|
|
|
int h_errno;
|
|
|
|
/*
|
|
* Formulate a normal query, send, and await answer.
|
|
* Returned answer is placed in supplied buffer "answer".
|
|
* Perform preliminary check of answer, returning success only
|
|
* if no error is indicated and the answer count is nonzero.
|
|
* Return the size of the response on success, -1 on error.
|
|
* Error number is left in h_errno.
|
|
* Caller must parse answer and determine whether it answers the question.
|
|
*/
|
|
res_query(name, class, type, answer, anslen)
|
|
char *name; /* domain name */
|
|
int class, type; /* class and type of query */
|
|
u_char *answer; /* buffer to put answer */
|
|
int anslen; /* size of answer buffer */
|
|
{
|
|
char buf[MAXPACKET];
|
|
HEADER *hp;
|
|
int n;
|
|
|
|
if ((_res.options & RES_INIT) == 0 && res_init() == -1)
|
|
return (-1);
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
printf(";; res_query(%s, %d, %d)\n", name, class, type);
|
|
#endif
|
|
n = res_mkquery(QUERY, name, class, type, (char *)NULL, 0, NULL,
|
|
buf, sizeof(buf));
|
|
|
|
if (n <= 0) {
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
printf(";; res_query: mkquery failed\n");
|
|
#endif
|
|
h_errno = NO_RECOVERY;
|
|
return (n);
|
|
}
|
|
n = res_send(buf, n, (char *)answer, anslen);
|
|
if (n < 0) {
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
printf(";; res_query: send error\n");
|
|
#endif
|
|
h_errno = TRY_AGAIN;
|
|
return(n);
|
|
}
|
|
|
|
hp = (HEADER *) answer;
|
|
if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) {
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
printf(";; rcode = %d, ancount=%d\n", hp->rcode,
|
|
ntohs(hp->ancount));
|
|
#endif
|
|
switch (hp->rcode) {
|
|
case NXDOMAIN:
|
|
h_errno = HOST_NOT_FOUND;
|
|
break;
|
|
case SERVFAIL:
|
|
h_errno = TRY_AGAIN;
|
|
break;
|
|
case NOERROR:
|
|
h_errno = NO_DATA;
|
|
break;
|
|
case FORMERR:
|
|
case NOTIMP:
|
|
case REFUSED:
|
|
default:
|
|
h_errno = NO_RECOVERY;
|
|
break;
|
|
}
|
|
return (-1);
|
|
}
|
|
return(n);
|
|
}
|
|
|
|
/*
|
|
* Formulate a normal query, send, and retrieve answer in supplied buffer.
|
|
* Return the size of the response on success, -1 on error.
|
|
* If enabled, implement search rules until answer or unrecoverable failure
|
|
* is detected. Error number is left in h_errno.
|
|
* Only useful for queries in the same name hierarchy as the local host
|
|
* (not, for example, for host address-to-name lookups in domain in-addr.arpa).
|
|
*/
|
|
int
|
|
res_search(name, class, type, answer, anslen)
|
|
char *name; /* domain name */
|
|
int class, type; /* class and type of query */
|
|
u_char *answer; /* buffer to put answer */
|
|
int anslen; /* size of answer */
|
|
{
|
|
register char *cp, **domain;
|
|
int n, ret, got_nodata = 0;
|
|
char *__hostalias();
|
|
|
|
if ((_res.options & RES_INIT) == 0 && res_init() == -1)
|
|
return (-1);
|
|
|
|
errno = 0;
|
|
h_errno = HOST_NOT_FOUND; /* default, if we never query */
|
|
for (cp = name, n = 0; *cp; cp++)
|
|
if (*cp == '.')
|
|
n++;
|
|
if (n == 0 && (cp = __hostalias(name)))
|
|
return (res_query(cp, class, type, answer, anslen));
|
|
|
|
/*
|
|
* We do at least one level of search if
|
|
* - there is no dot and RES_DEFNAME is set, or
|
|
* - there is at least one dot, there is no trailing dot,
|
|
* and RES_DNSRCH is set.
|
|
*/
|
|
if ((n == 0 && _res.options & RES_DEFNAMES) ||
|
|
(n != 0 && *--cp != '.' && _res.options & RES_DNSRCH))
|
|
for (domain = _res.dnsrch; *domain; domain++) {
|
|
ret = res_querydomain(name, *domain, class, type,
|
|
answer, anslen);
|
|
if (ret > 0)
|
|
return (ret);
|
|
/*
|
|
* If no server present, give up.
|
|
* If name isn't found in this domain,
|
|
* keep trying higher domains in the search list
|
|
* (if that's enabled).
|
|
* On a NO_DATA error, keep trying, otherwise
|
|
* a wildcard entry of another type could keep us
|
|
* from finding this entry higher in the domain.
|
|
* If we get some other error (negative answer or
|
|
* server failure), then stop searching up,
|
|
* but try the input name below in case it's fully-qualified.
|
|
*/
|
|
if (errno == ECONNREFUSED) {
|
|
h_errno = TRY_AGAIN;
|
|
return (-1);
|
|
}
|
|
if (h_errno == NO_DATA)
|
|
got_nodata++;
|
|
if ((h_errno != HOST_NOT_FOUND && h_errno != NO_DATA) ||
|
|
(_res.options & RES_DNSRCH) == 0)
|
|
break;
|
|
}
|
|
/*
|
|
* If the search/default failed, try the name as fully-qualified,
|
|
* but only if it contained at least one dot (even trailing).
|
|
* This is purely a heuristic; we assume that any reasonable query
|
|
* about a top-level domain (for servers, SOA, etc) will not use
|
|
* res_search.
|
|
*/
|
|
if (n && (ret = res_querydomain(name, (char *)NULL, class, type,
|
|
answer, anslen)) > 0)
|
|
return (ret);
|
|
if (got_nodata)
|
|
h_errno = NO_DATA;
|
|
return (-1);
|
|
}
|
|
|
|
/*
|
|
* Perform a call on res_query on the concatenation of name and domain,
|
|
* removing a trailing dot from name if domain is NULL.
|
|
*/
|
|
res_querydomain(name, domain, class, type, answer, anslen)
|
|
char *name, *domain;
|
|
int class, type; /* class and type of query */
|
|
u_char *answer; /* buffer to put answer */
|
|
int anslen; /* size of answer */
|
|
{
|
|
char nbuf[2*MAXDNAME+2];
|
|
char *longname = nbuf;
|
|
int n;
|
|
|
|
#ifdef DEBUG
|
|
if (_res.options & RES_DEBUG)
|
|
printf(";; res_querydomain(%s, %s, %d, %d)\n",
|
|
name, domain, class, type);
|
|
#endif
|
|
if (domain == NULL) {
|
|
/*
|
|
* Check for trailing '.';
|
|
* copy without '.' if present.
|
|
*/
|
|
n = strlen(name) - 1;
|
|
if (name[n] == '.' && n < sizeof(nbuf) - 1) {
|
|
bcopy(name, nbuf, n);
|
|
nbuf[n] = '\0';
|
|
} else
|
|
longname = name;
|
|
} else
|
|
(void)sprintf(nbuf, "%.*s.%.*s",
|
|
MAXDNAME, name, MAXDNAME, domain);
|
|
|
|
return (res_query(longname, class, type, answer, anslen));
|
|
}
|
|
|
|
char *
|
|
__hostalias(name)
|
|
register const char *name;
|
|
{
|
|
register char *C1, *C2;
|
|
FILE *fp;
|
|
char *file, *getenv(), *strcpy(), *strncpy();
|
|
char buf[BUFSIZ];
|
|
static char abuf[MAXDNAME];
|
|
|
|
file = getenv("HOSTALIASES");
|
|
if (file == NULL || (fp = fopen(file, "r")) == NULL)
|
|
return (NULL);
|
|
buf[sizeof(buf) - 1] = '\0';
|
|
while (fgets(buf, sizeof(buf), fp)) {
|
|
for (C1 = buf; *C1 && !isspace(*C1); ++C1);
|
|
if (!*C1)
|
|
break;
|
|
*C1 = '\0';
|
|
if (!strcasecmp(buf, name)) {
|
|
while (isspace(*++C1));
|
|
if (!*C1)
|
|
break;
|
|
for (C2 = C1 + 1; *C2 && !isspace(*C2); ++C2);
|
|
abuf[sizeof(abuf) - 1] = *C2 = '\0';
|
|
(void)strncpy(abuf, C1, sizeof(abuf) - 1);
|
|
fclose(fp);
|
|
return (abuf);
|
|
}
|
|
}
|
|
fclose(fp);
|
|
return (NULL);
|
|
}
|