diff options
Diffstat (limited to 'contrib/bind/named/db_lookup.c')
| -rw-r--r-- | contrib/bind/named/db_lookup.c | 249 |
1 files changed, 249 insertions, 0 deletions
diff --git a/contrib/bind/named/db_lookup.c b/contrib/bind/named/db_lookup.c new file mode 100644 index 0000000..4582589 --- /dev/null +++ b/contrib/bind/named/db_lookup.c @@ -0,0 +1,249 @@ +#if !defined(lint) && !defined(SABER) +static char sccsid[] = "@(#)db_lookup.c 4.18 (Berkeley) 3/21/91"; +static char rcsid[] = "$Id: db_lookup.c,v 8.7 1996/08/05 08:31:30 vixie Exp $"; +#endif /* not lint */ + +/* + * ++Copyright++ 1986 + * - + * 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. + * - + * --Copyright-- + */ + +/* + * Table lookup routines. + */ + +#include <sys/types.h> +#include <sys/param.h> +#include <sys/socket.h> +#include <netinet/in.h> +#include <arpa/nameser.h> +#include <ctype.h> +#include <stdio.h> +#include <syslog.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(name, htpp, fname, insert) + const char *name; + struct hashbuf **htpp; + const char **fname; + int insert; +{ + register struct namebuf *np; + register const char *cp; + register int c; + register unsigned hval; + register struct hashbuf *htp; + struct namebuf *parent = NULL; + int escaped = 0; + + htp = *htpp; + hval = 0; + *fname = "???"; + for (cp = name; c = *cp++; ) { + 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; + } + + /* rotate left HASHSHIFT */ + hval = (hval << HASHSHIFT) | + (hval>>((sizeof(hval)*8)-HASHSHIFT)); + hval += (isupper(c) ? tolower(c) : c) & HASHMASK; + 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 && + (NAMELEN(*np) == (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 * 2) { + *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_req.c + */ +struct namebuf * +np_parent(np) + 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 ; np=np->n_next) { + if (NAME(*np)[0] == '\0') + /* found the root namebuf */ + return (np); + } + dprintf(1, (ddt, + "np_parent(0x%lx) couldn't find root entry\n", + (u_long) np)); + return (NULL); /* XXX shouldn't happen */ + } + } + /* Try the hints. */ + if (htp == hashtab) { + htp = fcachetab; + goto try_again; + } + dprintf(1, (ddt, "np_parent(0x%lx) couldn't namebuf\n", (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(dp, class, type) + register struct databuf *dp; + register int class, type; +{ + dprintf(5, (ddt, "match(0x%lx, %d, %d) %d, %d\n", + (u_long)dp, class, type, dp->d_class, dp->d_type)); + if (dp->d_class != class && class != C_ANY) + return (0); + if (dp->d_type != type && type != T_ANY) + return (0); + return (1); +} |
