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 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 /* 31 * Portions Copyright (c) 1993 by Digital Equipment Corporation. 32 * 33 * Permission to use, copy, modify, and distribute this software for any 34 * purpose with or without fee is hereby granted, provided that the above 35 * copyright notice and this permission notice appear in all copies, and that 36 * the name of Digital Equipment Corporation not be used in advertising or 37 * publicity pertaining to distribution of the document or software without 38 * specific, written prior permission. 39 * 40 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL 41 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES 42 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT 43 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 44 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 45 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS 46 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 47 * SOFTWARE. 48 */ 49 50 /* 51 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") 52 * Portions Copyright (c) 1996-1999 by Internet Software Consortium. 53 * 54 * Permission to use, copy, modify, and distribute this software for any 55 * purpose with or without fee is hereby granted, provided that the above 56 * copyright notice and this permission notice appear in all copies. 57 * 58 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES 59 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 60 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR 61 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 62 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 63 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT 64 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 65 */ 66 67 #if defined(LIBC_SCCS) && !defined(lint) 68 static const char sccsid[] = "@(#)res_comp.c 8.1 (Berkeley) 6/4/93"; 69 static const char rcsid[] = "$Id: res_comp.c,v 1.3.18.2 2005/07/28 07:38:11 marka Exp $"; 70 #endif /* LIBC_SCCS and not lint */ 71 #include <sys/cdefs.h> 72 __FBSDID("$FreeBSD$"); 73 74 #include "port_before.h" 75 #include <sys/types.h> 76 #include <sys/param.h> 77 #include <netinet/in.h> 78 #include <arpa/nameser.h> 79 #include <ctype.h> 80 #include <resolv.h> 81 #include <stdio.h> 82 #include <string.h> 83 #include <unistd.h> 84 #include "port_after.h" 85 86 /*% 87 * Expand compressed domain name 'src' to full domain name. 88 * 89 * \li 'msg' is a pointer to the begining of the message, 90 * \li 'eom' points to the first location after the message, 91 * \li 'dst' is a pointer to a buffer of size 'dstsiz' for the result. 92 * \li Return size of compressed name or -1 if there was an error. 93 */ 94 int 95 dn_expand(const u_char *msg, const u_char *eom, const u_char *src, 96 char *dst, int dstsiz) 97 { 98 int n = ns_name_uncompress(msg, eom, src, dst, (size_t)dstsiz); 99 100 if (n > 0 && dst[0] == '.') 101 dst[0] = '\0'; 102 return (n); 103 } 104 105 /*% 106 * Pack domain name 'exp_dn' in presentation form into 'comp_dn'. 107 * 108 * \li Return the size of the compressed name or -1. 109 * \li 'length' is the size of the array pointed to by 'comp_dn'. 110 */ 111 int 112 dn_comp(const char *src, u_char *dst, int dstsiz, 113 u_char **dnptrs, u_char **lastdnptr) 114 { 115 return (ns_name_compress(src, dst, (size_t)dstsiz, 116 (const u_char **)dnptrs, 117 (const u_char **)lastdnptr)); 118 } 119 120 /*% 121 * Skip over a compressed domain name. Return the size or -1. 122 */ 123 int 124 dn_skipname(const u_char *ptr, const u_char *eom) { 125 const u_char *saveptr = ptr; 126 127 if (ns_name_skip(&ptr, eom) == -1) 128 return (-1); 129 return (ptr - saveptr); 130 } 131 132 /*% 133 * Verify that a domain name uses an acceptable character set. 134 * 135 * Note the conspicuous absence of ctype macros in these definitions. On 136 * non-ASCII hosts, we can't depend on string literals or ctype macros to 137 * tell us anything about network-format data. The rest of the BIND system 138 * is not careful about this, but for some reason, we're doing it right here. 139 */ 140 #define PERIOD 0x2e 141 #define hyphenchar(c) ((c) == 0x2d) 142 #define bslashchar(c) ((c) == 0x5c) 143 #define underscorechar(c) ((c) == 0x5f) 144 #define periodchar(c) ((c) == PERIOD) 145 #define asterchar(c) ((c) == 0x2a) 146 #define alphachar(c) (((c) >= 0x41 && (c) <= 0x5a) \ 147 || ((c) >= 0x61 && (c) <= 0x7a)) 148 #define digitchar(c) ((c) >= 0x30 && (c) <= 0x39) 149 150 #define borderchar(c) (alphachar(c) || digitchar(c)) 151 #ifdef RES_ENFORCE_RFC1034 152 #define middlechar(c) (borderchar(c) || hyphenchar(c)) 153 #else 154 #define middlechar(c) (borderchar(c) || hyphenchar(c) || underscorechar(c)) 155 #endif 156 #define domainchar(c) ((c) > 0x20 && (c) < 0x7f) 157 158 int 159 res_hnok(const char *dn) { 160 int pch = PERIOD, ch = *dn++; 161 162 while (ch != '\0') { 163 int nch = *dn++; 164 165 if (periodchar(ch)) { 166 (void)NULL; 167 } else if (periodchar(pch)) { 168 if (!borderchar(ch)) 169 return (0); 170 } else if (periodchar(nch) || nch == '\0') { 171 if (!borderchar(ch)) 172 return (0); 173 } else { 174 if (!middlechar(ch)) 175 return (0); 176 } 177 pch = ch, ch = nch; 178 } 179 return (1); 180 } 181 182 /*% 183 * hostname-like (A, MX, WKS) owners can have "*" as their first label 184 * but must otherwise be as a host name. 185 */ 186 int 187 res_ownok(const char *dn) { 188 if (asterchar(dn[0])) { 189 if (periodchar(dn[1])) 190 return (res_hnok(dn+2)); 191 if (dn[1] == '\0') 192 return (1); 193 } 194 return (res_hnok(dn)); 195 } 196 197 /*% 198 * SOA RNAMEs and RP RNAMEs can have any printable character in their first 199 * label, but the rest of the name has to look like a host name. 200 */ 201 int 202 res_mailok(const char *dn) { 203 int ch, escaped = 0; 204 205 /* "." is a valid missing representation */ 206 if (*dn == '\0') 207 return (1); 208 209 /* otherwise <label>.<hostname> */ 210 while ((ch = *dn++) != '\0') { 211 if (!domainchar(ch)) 212 return (0); 213 if (!escaped && periodchar(ch)) 214 break; 215 if (escaped) 216 escaped = 0; 217 else if (bslashchar(ch)) 218 escaped = 1; 219 } 220 if (periodchar(ch)) 221 return (res_hnok(dn)); 222 return (0); 223 } 224 225 /*% 226 * This function is quite liberal, since RFC1034's character sets are only 227 * recommendations. 228 */ 229 int 230 res_dnok(const char *dn) { 231 int ch; 232 233 while ((ch = *dn++) != '\0') 234 if (!domainchar(ch)) 235 return (0); 236 return (1); 237 } 238 239 #ifdef BIND_4_COMPAT 240 /*% 241 * This module must export the following externally-visible symbols: 242 * ___putlong 243 * ___putshort 244 * __getlong 245 * __getshort 246 * Note that one _ comes from C and the others come from us. 247 */ 248 249 #ifdef SOLARIS2 250 #ifdef __putlong 251 #undef __putlong 252 #endif 253 #ifdef __putshort 254 #undef __putshort 255 #endif 256 #pragma weak putlong = __putlong 257 #pragma weak putshort = __putshort 258 #endif /* SOLARIS2 */ 259 260 void __putlong(u_int32_t src, u_char *dst) { ns_put32(src, dst); } 261 void __putshort(u_int16_t src, u_char *dst) { ns_put16(src, dst); } 262 #ifndef __ultrix__ 263 u_int32_t _getlong(const u_char *src) { return (ns_get32(src)); } 264 u_int16_t _getshort(const u_char *src) { return (ns_get16(src)); } 265 #endif /*__ultrix__*/ 266 #endif /*BIND_4_COMPAT*/ 267 268 /* 269 * Weak aliases for applications that use certain private entry points, 270 * and fail to include <resolv.h>. 271 */ 272 #undef dn_comp 273 __weak_reference(__dn_comp, dn_comp); 274 #undef dn_expand 275 __weak_reference(__dn_expand, dn_expand); 276 277 /*! \file */ 278