NetBSD/dist/bind/bin/named/db_lookup.c

334 lines
9.9 KiB
C

/* $NetBSD: db_lookup.c,v 1.1.1.1 1999/11/20 18:53:59 veego Exp $ */
#if !defined(lint) && !defined(SABER)
static const char sccsid[] = "@(#)db_lookup.c 4.18 (Berkeley) 3/21/91";
static const char rcsid[] = "Id: db_lookup.c,v 8.24 1999/10/15 19:48:58 vixie Exp";
#endif /* not lint */
/*
* Copyright (c) 1986
* 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) 1996-1999 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.
*/
/*
* Table lookup routines.
*/
#include "port_before.h"
#include <sys/types.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <ctype.h>
#include <stdio.h>
#include <string.h>
#include <syslog.h>
#include <time.h>
#include <isc/eventlib.h>
#include <isc/logging.h>
#include "port_after.h"
#include "named.h"
/*
* Lookup 'name' and return a pointer to the namebuf;
* NULL otherwise. If 'insert', insert name into tables.
* Wildcard lookups are handled.
*/
struct namebuf *
nlookup(const char *name, struct hashbuf **htpp,
const char **fname, int insert)
{
struct namebuf *np;
const char *cp;
int c;
u_int hval;
struct hashbuf *htp;
struct namebuf *parent = NULL;
int escaped = 0;
htp = *htpp;
hval = 0;
*fname = "???";
for (cp = name; (c = *cp++) != 0; (void)NULL) {
if (!escaped && (c == '.')) {
parent = np = nlookup(cp, htpp, fname, insert);
if (np == NULL)
return (NULL);
if (*fname != cp)
return (np);
if ((htp = np->n_hash) == NULL) {
if (!insert) {
if (ns_wildcard(NAME(*np)))
*fname = name;
return (np);
}
htp = savehash((struct hashbuf *)NULL);
np->n_hash = htp;
}
*htpp = htp;
break;
}
HASHIMILATE(hval, c);
if (escaped)
escaped = 0;
else if (c == '\\')
escaped = 1;
}
cp--;
/*
* Lookup this label in current hash table.
*/
for (np = htp->h_tab[hval % htp->h_size];
np != NULL;
np = np->n_next) {
if (np->n_hashval == hval &&
((size_t)NAMELEN(*np) == (size_t)(cp - name)) &&
(strncasecmp(name, NAME(*np), cp - name) == 0)) {
*fname = name;
return (np);
}
}
if (!insert) {
/*
* Look for wildcard in this hash table.
* Don't use a cached "*" name as a wildcard,
* only authoritative.
*/
hval = ('*' & HASHMASK) % htp->h_size;
for (np = htp->h_tab[hval]; np != NULL; np = np->n_next) {
if (ns_wildcard(NAME(*np)) &&
np->n_data && np->n_data->d_zone != 0) {
*fname = name;
return (np);
}
}
return (parent);
}
np = savename(name, cp - name);
np->n_parent = parent;
np->n_hashval = hval;
hval %= htp->h_size;
np->n_next = htp->h_tab[hval];
htp->h_tab[hval] = np;
/* Increase hash table size. */
if (++htp->h_cnt > (htp->h_size * AVGCH_NLOOKUP)) {
*htpp = savehash(htp);
if (parent == NULL) {
if (htp == hashtab) {
hashtab = *htpp;
} else {
fcachetab = *htpp;
}
}
else
parent->n_hash = *htpp;
htp = *htpp;
}
*fname = name;
return (np);
}
/* struct namebuf *
* np_parent(struct namebuf *np)
* Find the "parent" namebuf of np.
* This is tricky since the parent of "com" is "" and both are stored
* in the same hashbuf.
* See also:
* the AXFR wart description in ns_axfr.c
*/
struct namebuf *
np_parent(struct namebuf *np) {
struct hashbuf *htp;
struct namebuf *np2;
if (np->n_parent != NULL || NAME(*np)[0] == '\0')
return (np->n_parent);
/* Try to figure out if np is pointing into the cache or hints. */
/* Try the cache first. */
htp = hashtab;
try_again:
/* Search the hash chain that np should be part of. */
for (np2 = htp->h_tab[np->n_hashval % htp->h_size];
np2 != NULL;
np2 = np2->n_next)
{
if (np == np2) { /* found it! */
/* "" hashes into the first bucket */
for (np = htp->h_tab[0]; np != NULL; np = np->n_next) {
if (NAME(*np)[0] == '\0')
/* found the root namebuf */
return (np);
}
/* there are no RR's with a owner name of "." yet */
return (NULL);
}
}
/* Try the hints. */
if (htp == hashtab) {
htp = fcachetab;
goto try_again;
}
ns_debug(ns_log_db, 1, "np_parent(0x%lx) couldn't find namebuf",
(u_long)np);
return (NULL); /* XXX shouldn't happen */
}
/* int
* match(dp, class, type)
* Does data record `dp' match the class and type?
* return value:
* boolean
*/
int
match(struct databuf *dp, int class, int type) {
if (dp->d_class != class && class != C_ANY)
return (0);
if (dp->d_type != type && dp->d_type != T_SIG && type != T_ANY)
return (0);
if (type != T_SIG && dp->d_type == T_SIG && SIG_COVERS(dp) != type)
return (0);
return (1);
}
/* static int
* nxtlower(name, dp)
* Is the NXT/SIG NXT record 'lower'?
* return value:
* boolean
*/
static int
nxtlower(const char *name, struct databuf *dp) {
/* An NXT is a lower NXT iff the SOA bit is set in the bitmap */
if (dp->d_type == T_NXT) {
u_char *nxtbitmap = dp->d_data + strlen((char *)dp->d_data) + 1;
return (NS_NXT_BIT_ISSET(T_SOA, nxtbitmap) ? 1 : 0);
}
/* If it's not an NXT, it's a SIG NXT. An NXT record must be signed
* by the zone, so the signer name must be the same as the owner.
*/
return (ns_samename(name, (char *)dp->d_data + SIG_HDR_SIZE) != 1 ? 0 : 1);
}
/* int
* nxtmatch(name, dp1, dp2)
* Do NXT/SIG NXT records `dp1' and `dp2' belong to the same NXT set?
* return value:
* boolean
*/
int
nxtmatch(const char *name, struct databuf *dp1, struct databuf *dp2) {
int dp1_lower, dp2_lower;
if (dp1->d_type != ns_t_nxt || dp2->d_type != ns_t_nxt)
return (0);
dp1_lower = nxtlower(name, dp1);
dp2_lower = nxtlower(name, dp2);
return (dp1_lower == dp2_lower);
}
/* int
* rrmatch(name, dp1, dp2)
* Do data records `dp1' and `dp2' match in class and type?
* If both are NXTs, do they belong in the same NXT set?
* If both are SIGs, do the covered types match?
* If both are SIG NXTs, do the covered NXTs belong in the same set?
* Why is DNSSEC so confusing?
* return value:
* boolean
*/
int
rrmatch(const char *name, struct databuf *dp1, struct databuf *dp2) {
if (dp1->d_class != dp2->d_class &&
dp1->d_class != C_ANY && dp2->d_class != C_ANY)
return(0);
if (dp1->d_type != dp2->d_type &&
dp1->d_type != T_ANY && dp2->d_type != T_ANY)
return(0);
if (dp1->d_type == T_NXT)
return(nxtmatch(name, dp1, dp2));
if (dp1->d_type != T_SIG)
return(1);
if (SIG_COVERS(dp1) == SIG_COVERS(dp2)) {
if (SIG_COVERS(dp1) == ns_t_nxt)
return(nxtmatch(name, dp1, dp2));
else
return(1);
}
return(0);
}