1/*
2 * Copyright (c) 1985, 1993
3 *    The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 * 	This product includes software developed by the University of
16 * 	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34/*
35 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
36 *
37 * Permission to use, copy, modify, and distribute this software for any
38 * purpose with or without fee is hereby granted, provided that the above
39 * copyright notice and this permission notice appear in all copies, and that
40 * the name of Digital Equipment Corporation not be used in advertising or
41 * publicity pertaining to distribution of the document or software without
42 * specific, written prior permission.
43 *
44 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
45 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
46 * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
47 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
48 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
49 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
50 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
51 * SOFTWARE.
52 */
53
54/*
55 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
56 * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
57 *
58 * Permission to use, copy, modify, and distribute this software for any
59 * purpose with or without fee is hereby granted, provided that the above
60 * copyright notice and this permission notice appear in all copies.
61 *
62 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
63 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
64 * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
65 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
66 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
67 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
68 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
69 */
70
71#if defined(LIBC_SCCS) && !defined(lint)
72static const char sccsid[] = "@(#)res_comp.c	8.1 (Berkeley) 6/4/93";
73static const char rcsid[] = "$Id: res_comp.c,v 1.5 2005/07/28 06:51:50 marka Exp $";
74#endif /* LIBC_SCCS and not lint */
75
76#include "port_before.h"
77#include <sys/types.h>
78#include <sys/param.h>
79#include <netinet/in.h>
80#include <arpa/nameser.h>
81#include <ctype.h>
82#include <resolv.h>
83#include <stdio.h>
84#include <string.h>
85#include <unistd.h>
86#include "port_after.h"
87
88/*%
89 * Expand compressed domain name 'src' to full domain name.
90 *
91 * \li 'msg' is a pointer to the begining of the message,
92 * \li 'eom' points to the first location after the message,
93 * \li 'dst' is a pointer to a buffer of size 'dstsiz' for the result.
94 * \li Return size of compressed name or -1 if there was an error.
95 */
96int
97dn_expand(const u_char *msg, const u_char *eom, const u_char *src,
98	  char *dst, int dstsiz)
99{
100	int n = ns_name_uncompress(msg, eom, src, dst, (size_t)dstsiz);
101
102	if (n > 0 && dst[0] == '.')
103		dst[0] = '\0';
104	return (n);
105}
106
107/*%
108 * Pack domain name 'exp_dn' in presentation form into 'comp_dn'.
109 *
110 * \li Return the size of the compressed name or -1.
111 * \li 'length' is the size of the array pointed to by 'comp_dn'.
112 */
113int
114dn_comp(const char *src, u_char *dst, int dstsiz,
115	u_char **dnptrs, u_char **lastdnptr)
116{
117	return (ns_name_compress(src, dst, (size_t)dstsiz,
118				 (const u_char **)dnptrs,
119				 (const u_char **)lastdnptr));
120}
121
122/*%
123 * Skip over a compressed domain name. Return the size or -1.
124 */
125int
126dn_skipname(const u_char *ptr, const u_char *eom) {
127	const u_char *saveptr = ptr;
128
129	if (ns_name_skip(&ptr, eom) == -1)
130		return (-1);
131	return (ptr - saveptr);
132}
133
134/*%
135 * Verify that a domain name uses an acceptable character set.
136 *
137 * Note the conspicuous absence of ctype macros in these definitions.  On
138 * non-ASCII hosts, we can't depend on string literals or ctype macros to
139 * tell us anything about network-format data.  The rest of the BIND system
140 * is not careful about this, but for some reason, we're doing it right here.
141 */
142#define PERIOD 0x2e
143#define	hyphenchar(c) ((c) == 0x2d)
144#define bslashchar(c) ((c) == 0x5c)
145#define periodchar(c) ((c) == PERIOD)
146#define asterchar(c) ((c) == 0x2a)
147#define alphachar(c) (((c) >= 0x41 && (c) <= 0x5a) \
148		   || ((c) >= 0x61 && (c) <= 0x7a))
149#define digitchar(c) ((c) >= 0x30 && (c) <= 0x39)
150
151#define borderchar(c) (alphachar(c) || digitchar(c))
152#define middlechar(c) (borderchar(c) || hyphenchar(c))
153#define	domainchar(c) ((c) > 0x20 && (c) < 0x7f)
154
155int
156res_hnok(const char *dn) {
157	int pch = PERIOD, ch = *dn++;
158
159	while (ch != '\0') {
160		int nch = *dn++;
161
162		if (periodchar(ch)) {
163			(void)NULL;
164		} else if (periodchar(pch)) {
165			if (!borderchar(ch))
166				return (0);
167		} else if (periodchar(nch) || nch == '\0') {
168			if (!borderchar(ch))
169				return (0);
170		} else {
171			if (!middlechar(ch))
172				return (0);
173		}
174		pch = ch, ch = nch;
175	}
176	return (1);
177}
178
179/*%
180 * hostname-like (A, MX, WKS) owners can have "*" as their first label
181 * but must otherwise be as a host name.
182 */
183int
184res_ownok(const char *dn) {
185	if (asterchar(dn[0])) {
186		if (periodchar(dn[1]))
187			return (res_hnok(dn+2));
188		if (dn[1] == '\0')
189			return (1);
190	}
191	return (res_hnok(dn));
192}
193
194/*%
195 * SOA RNAMEs and RP RNAMEs can have any printable character in their first
196 * label, but the rest of the name has to look like a host name.
197 */
198int
199res_mailok(const char *dn) {
200	int ch, escaped = 0;
201
202	/* "." is a valid missing representation */
203	if (*dn == '\0')
204		return (1);
205
206	/* otherwise <label>.<hostname> */
207	while ((ch = *dn++) != '\0') {
208		if (!domainchar(ch))
209			return (0);
210		if (!escaped && periodchar(ch))
211			break;
212		if (escaped)
213			escaped = 0;
214		else if (bslashchar(ch))
215			escaped = 1;
216	}
217	if (periodchar(ch))
218		return (res_hnok(dn));
219	return (0);
220}
221
222/*%
223 * This function is quite liberal, since RFC1034's character sets are only
224 * recommendations.
225 */
226int
227res_dnok(const char *dn) {
228	int ch;
229
230	while ((ch = *dn++) != '\0')
231		if (!domainchar(ch))
232			return (0);
233	return (1);
234}
235
236#ifdef BIND_4_COMPAT
237/*%
238 * This module must export the following externally-visible symbols:
239 *	___putlong
240 *	___putshort
241 *	__getlong
242 *	__getshort
243 * Note that one _ comes from C and the others come from us.
244 */
245
246#ifdef SOLARIS2
247#ifdef  __putlong
248#undef  __putlong
249#endif
250#ifdef  __putshort
251#undef  __putshort
252#endif
253#pragma weak    putlong         =       __putlong
254#pragma weak    putshort        =       __putshort
255#endif /* SOLARIS2 */
256
257void __putlong(u_int32_t src, u_char *dst) { ns_put32(src, dst); }
258void __putshort(u_int16_t src, u_char *dst) { ns_put16(src, dst); }
259#ifndef __ultrix__
260u_int32_t _getlong(const u_char *src) { return (ns_get32(src)); }
261u_int16_t _getshort(const u_char *src) { return (ns_get16(src)); }
262#endif /*__ultrix__*/
263#endif /*BIND_4_COMPAT*/
264
265/*! \file */
266