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4 * Copyright (c) 1985, 1993
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33 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
35 * Permission to use, copy, modify, and distribute this software for any
36 * purpose with or without fee is hereby granted, provided that the above
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48 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
53 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
54 * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
56 * Permission to use, copy, modify, and distribute this software for any
57 * purpose with or without fee is hereby granted, provided that the above
58 * copyright notice and this permission notice appear in all copies.
60 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
61 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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63 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
64 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
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66 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
69 #if defined(LIBC_SCCS) && !defined(lint)
70 static const char sccsid[] = "@(#)res_comp.c 8.1 (Berkeley) 6/4/93";
71 static const char rcsid[] = "$Id: res_comp.c,v 1.5 2005/07/28 06:51:50 marka Exp $";
72 #endif /* LIBC_SCCS and not lint */
73 #include <sys/cdefs.h>
74 __FBSDID("$FreeBSD$");
76 #include "port_before.h"
77 #include <sys/param.h>
78 #include <netinet/in.h>
79 #include <arpa/nameser.h>
85 #include "port_after.h"
88 * Expand compressed domain name 'src' to full domain name.
90 * \li 'msg' is a pointer to the beginning of the message,
91 * \li 'eom' points to the first location after the message,
92 * \li 'dst' is a pointer to a buffer of size 'dstsiz' for the result.
93 * \li Return size of compressed name or -1 if there was an error.
96 dn_expand(const u_char *msg, const u_char *eom, const u_char *src,
97 char *dst, int dstsiz)
99 int n = ns_name_uncompress(msg, eom, src, dst, (size_t)dstsiz);
101 if (n > 0 && dst[0] == '.')
107 * Pack domain name 'exp_dn' in presentation form into 'comp_dn'.
109 * \li Return the size of the compressed name or -1.
110 * \li 'length' is the size of the array pointed to by 'comp_dn'.
113 dn_comp(const char *src, u_char *dst, int dstsiz,
114 u_char **dnptrs, u_char **lastdnptr)
116 return (ns_name_compress(src, dst, (size_t)dstsiz,
117 (const u_char **)dnptrs,
118 (const u_char **)lastdnptr));
122 * Skip over a compressed domain name. Return the size or -1.
125 dn_skipname(const u_char *ptr, const u_char *eom) {
126 const u_char *saveptr = ptr;
128 if (ns_name_skip(&ptr, eom) == -1)
130 return (ptr - saveptr);
134 * Verify that a domain name uses an acceptable character set.
136 * Note the conspicuous absence of ctype macros in these definitions. On
137 * non-ASCII hosts, we can't depend on string literals or ctype macros to
138 * tell us anything about network-format data. The rest of the BIND system
139 * is not careful about this, but for some reason, we're doing it right here.
142 #define hyphenchar(c) ((c) == 0x2d)
143 #define bslashchar(c) ((c) == 0x5c)
144 #define underscorechar(c) ((c) == 0x5f)
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)
151 #ifdef RES_ENFORCE_RFC1034
152 #define borderchar(c) (alphachar(c) || digitchar(c))
154 #define borderchar(c) (alphachar(c) || digitchar(c) || underscorechar(c))
156 #define middlechar(c) (borderchar(c) || hyphenchar(c))
157 #define domainchar(c) ((c) > 0x20 && (c) < 0x7f)
160 res_hnok(const char *dn) {
161 int pch = PERIOD, ch = *dn++;
166 if (periodchar(ch)) {
168 } else if (periodchar(pch)) {
171 } else if (periodchar(nch) || nch == '\0') {
184 * hostname-like (A, MX, WKS) owners can have "*" as their first label
185 * but must otherwise be as a host name.
188 res_ownok(const char *dn) {
189 if (asterchar(dn[0])) {
190 if (periodchar(dn[1]))
191 return (res_hnok(dn+2));
195 return (res_hnok(dn));
199 * SOA RNAMEs and RP RNAMEs can have any printable character in their first
200 * label, but the rest of the name has to look like a host name.
203 res_mailok(const char *dn) {
206 /* "." is a valid missing representation */
210 /* otherwise <label>.<hostname> */
211 while ((ch = *dn++) != '\0') {
214 if (!escaped && periodchar(ch))
218 else if (bslashchar(ch))
222 return (res_hnok(dn));
227 * This function is quite liberal, since RFC1034's character sets are only
231 res_dnok(const char *dn) {
234 while ((ch = *dn++) != '\0')
242 * This module must export the following externally-visible symbols:
247 * Note that one _ comes from C and the others come from us.
257 #pragma weak putlong = __putlong
258 #pragma weak putshort = __putshort
259 #endif /* SOLARIS2 */
261 void __putlong(u_int32_t src, u_char *dst) { ns_put32(src, dst); }
262 void __putshort(u_int16_t src, u_char *dst) { ns_put16(src, dst); }
264 u_int32_t _getlong(const u_char *src) { return (ns_get32(src)); }
265 u_int16_t _getshort(const u_char *src) { return (ns_get16(src)); }
266 #endif /*__ultrix__*/
267 #endif /*BIND_4_COMPAT*/
270 * Weak aliases for applications that use certain private entry points,
271 * and fail to include <resolv.h>.
274 __weak_reference(__dn_comp, dn_comp);
276 __weak_reference(__dn_expand, dn_expand);