4.4BSD/usr/src/contrib/bind-4.9/named/ns_sort.c
#if !defined(lint) && !defined(SABER)
static char sccsid[] = "@(#)ns_sort.c 4.10 (Berkeley) 3/3/91";
static char rcsid[] = "$Id: ns_sort.c,v 4.9.1.1 1993/05/02 22:43:03 vixie Rel $";
#endif /* not lint */
/*
* ++Copyright++ 1986, 1990
* -
* Copyright (c) 1986, 1990 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--
*/
#include <sys/param.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <sys/file.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <syslog.h>
#include <resolv.h>
#include "../conf/portability.h"
#include "../conf/options.h"
#include "ns.h"
#include "db.h"
extern int debug;
extern FILE *ddt;
struct netinfo *local();
void sort_response();
int sort_rr();
struct netinfo *
local(from)
struct sockaddr_in *from;
{
extern struct netinfo *nettab, netloop, **enettab;
struct netinfo *ntp;
if (from->sin_addr.s_addr == netloop.my_addr.s_addr)
return( &netloop);
for (ntp = nettab; ntp != *enettab; ntp = ntp->next) {
if (ntp->net == (from->sin_addr.s_addr & ntp->mask))
return(ntp);
}
return(NULL);
}
void
sort_response(cp, ancount, lp, eom)
register char *cp;
register int ancount;
struct netinfo *lp;
u_char *eom;
{
register struct netinfo *ntp;
extern struct netinfo *nettab;
#ifdef DEBUG
if (debug > 2)
fprintf(ddt,"sort_response(%d)\n", ancount);
#endif
if (ancount > 1) {
if (sort_rr(cp, ancount, lp, eom))
return;
for (ntp = nettab; ntp != NULL; ntp = ntp->next) {
if ((ntp->net == lp->net) && (ntp->mask == lp->mask))
continue;
if (sort_rr(cp, ancount, ntp, eom))
break;
}
}
}
int
sort_rr(cp, count, ntp, eom)
register u_char *cp;
int count;
register struct netinfo *ntp;
u_char *eom;
{
int type, class, dlen, n, c;
struct in_addr inaddr;
u_char *rr1;
#ifdef DEBUG
if (debug > 2) {
inaddr.s_addr = ntp->net;
fprintf(ddt,"sort_rr( x%x, %d, %s)\n",cp, count,
inet_ntoa(inaddr));
}
#endif
rr1 = NULL;
for (c = count; c > 0; --c) {
n = dn_skipname(cp, eom);
if (n < 0)
return (1); /* bogus, stop processing */
cp += n;
if (cp + QFIXEDSZ > eom)
return (1);
GETSHORT(type, cp);
GETSHORT(class, cp);
cp += sizeof(u_int32_t);
GETSHORT(dlen, cp);
if (dlen > eom - cp)
return (1); /* bogus, stop processing */
switch (type) {
case T_A:
switch (class) {
case C_IN:
case C_HS:
bcopy(cp, (char *)&inaddr, sizeof(inaddr));
if (rr1 == NULL)
rr1 = cp;
if ((ntp->mask & inaddr.s_addr) == ntp->net) {
#ifdef DEBUG
if (debug > 1) {
fprintf(ddt,"net %s best choice\n",
inet_ntoa(inaddr));
}
#endif
if (rr1 != cp) {
bcopy(rr1, cp, sizeof(inaddr));
bcopy((char *)&inaddr, rr1, sizeof(inaddr));
}
return(1);
}
break;
}
break;
}
cp += dlen;
}
return(0);
}