1 /* $NetBSD: res_comp.c,v 1.6 2004/05/22 23:47:09 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1985, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 /* 37 * Portions Copyright (c) 1993 by Digital Equipment Corporation. 38 * 39 * Permission to use, copy, modify, and distribute this software for any 40 * purpose with or without fee is hereby granted, provided that the above 41 * copyright notice and this permission notice appear in all copies, and that 42 * the name of Digital Equipment Corporation not be used in advertising or 43 * publicity pertaining to distribution of the document or software without 44 * specific, written prior permission. 45 * 46 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL 47 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES 48 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT 49 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 50 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 51 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS 52 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 53 * SOFTWARE. 54 */ 55 56 /* 57 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") 58 * Portions Copyright (c) 1996-1999 by Internet Software Consortium. 59 * 60 * Permission to use, copy, modify, and distribute this software for any 61 * purpose with or without fee is hereby granted, provided that the above 62 * copyright notice and this permission notice appear in all copies. 63 * 64 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES 65 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 66 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR 67 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 68 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 69 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT 70 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 71 */ 72 #include <sys/cdefs.h> 73 #if defined(LIBC_SCCS) && !defined(lint) 74 #ifdef notdef 75 static const char sccsid[] = "@(#)res_comp.c 8.1 (Berkeley) 6/4/93"; 76 static const char rcsid[] = "Id: res_comp.c,v 1.1.2.1.4.1 2004/03/09 08:33:54 marka Exp"; 77 #else 78 __RCSID("$NetBSD: res_comp.c,v 1.6 2004/05/22 23:47:09 christos Exp $"); 79 #endif 80 #endif /* LIBC_SCCS and not lint */ 81 82 #include "port_before.h" 83 84 #include "namespace.h" 85 #include <sys/types.h> 86 #include <sys/param.h> 87 #include <netinet/in.h> 88 #include <arpa/nameser.h> 89 #include <ctype.h> 90 #include <resolv.h> 91 #include <stdio.h> 92 #include <string.h> 93 #include <unistd.h> 94 #include "port_after.h" 95 96 #ifdef __weak_alias 97 __weak_alias(dn_expand,_dn_expand) 98 __weak_alias(dn_comp,__dn_comp) 99 #if 0 100 __weak_alias(dn_skipname,__dn_skipname) 101 __weak_alias(res_hnok,__res_hnok) 102 __weak_alias(res_ownok,__res_ownok) 103 __weak_alias(res_mailok,__res_mailok) 104 __weak_alias(res_dnok,__res_dnok) 105 #endif 106 #endif 107 108 /* 109 * Expand compressed domain name 'src' to full domain name. 110 * 'msg' is a pointer to the begining of the message, 111 * 'eom' points to the first location after the message, 112 * 'dst' is a pointer to a buffer of size 'dstsiz' for the result. 113 * Return size of compressed name or -1 if there was an error. 114 */ 115 int 116 dn_expand(const u_char *msg, const u_char *eom, const u_char *src, 117 char *dst, int dstsiz) 118 { 119 int n = ns_name_uncompress(msg, eom, src, dst, (size_t)dstsiz); 120 121 if (n > 0 && dst[0] == '.') 122 dst[0] = '\0'; 123 return (n); 124 } 125 126 /* 127 * Pack domain name 'exp_dn' in presentation form into 'comp_dn'. 128 * Return the size of the compressed name or -1. 129 * 'length' is the size of the array pointed to by 'comp_dn'. 130 */ 131 int 132 dn_comp(const char *src, u_char *dst, int dstsiz, 133 u_char **dnptrs, u_char **lastdnptr) 134 { 135 return (ns_name_compress(src, dst, (size_t)dstsiz, 136 (const u_char **)dnptrs, 137 (const u_char **)lastdnptr)); 138 } 139 140 /* 141 * Skip over a compressed domain name. Return the size or -1. 142 */ 143 int 144 dn_skipname(const u_char *ptr, const u_char *eom) { 145 const u_char *saveptr = ptr; 146 147 if (ns_name_skip(&ptr, eom) == -1) 148 return (-1); 149 return (ptr - saveptr); 150 } 151 152 /* 153 * Verify that a domain name uses an acceptable character set. 154 */ 155 156 /* 157 * Note the conspicuous absence of ctype macros in these definitions. On 158 * non-ASCII hosts, we can't depend on string literals or ctype macros to 159 * tell us anything about network-format data. The rest of the BIND system 160 * is not careful about this, but for some reason, we're doing it right here. 161 */ 162 #define PERIOD 0x2e 163 #define hyphenchar(c) ((c) == 0x2d) 164 #define bslashchar(c) ((c) == 0x5c) 165 #define periodchar(c) ((c) == PERIOD) 166 #define asterchar(c) ((c) == 0x2a) 167 #define alphachar(c) (((c) >= 0x41 && (c) <= 0x5a) \ 168 || ((c) >= 0x61 && (c) <= 0x7a)) 169 #define digitchar(c) ((c) >= 0x30 && (c) <= 0x39) 170 171 #define borderchar(c) (alphachar(c) || digitchar(c)) 172 #define middlechar(c) (borderchar(c) || hyphenchar(c)) 173 #define domainchar(c) ((c) > 0x20 && (c) < 0x7f) 174 175 int 176 res_hnok(const char *dn) { 177 int pch = PERIOD, ch = *dn++; 178 179 while (ch != '\0') { 180 int nch = *dn++; 181 182 if (periodchar(ch)) { 183 ; 184 } else if (periodchar(pch)) { 185 if (!borderchar(ch)) 186 return (0); 187 } else if (periodchar(nch) || nch == '\0') { 188 if (!borderchar(ch)) 189 return (0); 190 } else { 191 if (!middlechar(ch)) 192 return (0); 193 } 194 pch = ch, ch = nch; 195 } 196 return (1); 197 } 198 199 /* 200 * hostname-like (A, MX, WKS) owners can have "*" as their first label 201 * but must otherwise be as a host name. 202 */ 203 int 204 res_ownok(const char *dn) { 205 if (asterchar(dn[0])) { 206 if (periodchar(dn[1])) 207 return (res_hnok(dn+2)); 208 if (dn[1] == '\0') 209 return (1); 210 } 211 return (res_hnok(dn)); 212 } 213 214 /* 215 * SOA RNAMEs and RP RNAMEs can have any printable character in their first 216 * label, but the rest of the name has to look like a host name. 217 */ 218 int 219 res_mailok(const char *dn) { 220 int ch, escaped = 0; 221 222 /* "." is a valid missing representation */ 223 if (*dn == '\0') 224 return (1); 225 226 /* otherwise <label>.<hostname> */ 227 while ((ch = *dn++) != '\0') { 228 if (!domainchar(ch)) 229 return (0); 230 if (!escaped && periodchar(ch)) 231 break; 232 if (escaped) 233 escaped = 0; 234 else if (bslashchar(ch)) 235 escaped = 1; 236 } 237 if (periodchar(ch)) 238 return (res_hnok(dn)); 239 return (0); 240 } 241 242 /* 243 * This function is quite liberal, since RFC 1034's character sets are only 244 * recommendations. 245 */ 246 int 247 res_dnok(const char *dn) { 248 int ch; 249 250 while ((ch = *dn++) != '\0') 251 if (!domainchar(ch)) 252 return (0); 253 return (1); 254 } 255 256 #ifdef BIND_4_COMPAT 257 /* 258 * This module must export the following externally-visible symbols: 259 * ___putlong 260 * ___putshort 261 * __getlong 262 * __getshort 263 * Note that one _ comes from C and the others come from us. 264 */ 265 void __putlong(u_int32_t src, u_char *dst) { ns_put32(src, dst); } 266 void __putshort(u_int16_t src, u_char *dst) { ns_put16(src, dst); } 267 #ifndef __ultrix__ 268 u_int32_t _getlong(const u_char *src) { return (ns_get32(src)); } 269 u_int16_t _getshort(const u_char *src) { return (ns_get16(src)); } 270 #endif /*__ultrix__*/ 271 #endif /*BIND_4_COMPAT*/ 272