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. 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 1.5 2005/07/28 06:51:50 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/param.h> 76 #include <netinet/in.h> 77 #include <arpa/nameser.h> 78 #include <ctype.h> 79 #include <resolv.h> 80 #include <stdio.h> 81 #include <string.h> 82 #include <unistd.h> 83 #include "port_after.h" 84 85 /*% 86 * Expand compressed domain name 'src' to full domain name. 87 * 88 * \li 'msg' is a pointer to the beginning of the message, 89 * \li 'eom' points to the first location after the message, 90 * \li 'dst' is a pointer to a buffer of size 'dstsiz' for the result. 91 * \li Return size of compressed name or -1 if there was an error. 92 */ 93 int 94 dn_expand(const u_char *msg, const u_char *eom, const u_char *src, 95 char *dst, int dstsiz) 96 { 97 int n = ns_name_uncompress(msg, eom, src, dst, (size_t)dstsiz); 98 99 if (n > 0 && dst[0] == '.') 100 dst[0] = '\0'; 101 return (n); 102 } 103 104 /*% 105 * Pack domain name 'exp_dn' in presentation form into 'comp_dn'. 106 * 107 * \li Return the size of the compressed name or -1. 108 * \li 'length' is the size of the array pointed to by 'comp_dn'. 109 */ 110 int 111 dn_comp(const char *src, u_char *dst, int dstsiz, 112 u_char **dnptrs, u_char **lastdnptr) 113 { 114 return (ns_name_compress(src, dst, (size_t)dstsiz, 115 (const u_char **)dnptrs, 116 (const u_char **)lastdnptr)); 117 } 118 119 /*% 120 * Skip over a compressed domain name. Return the size or -1. 121 */ 122 int 123 dn_skipname(const u_char *ptr, const u_char *eom) { 124 const u_char *saveptr = ptr; 125 126 if (ns_name_skip(&ptr, eom) == -1) 127 return (-1); 128 return (ptr - saveptr); 129 } 130 131 /*% 132 * Verify that a domain name uses an acceptable character set. 133 * 134 * Note the conspicuous absence of ctype macros in these definitions. On 135 * non-ASCII hosts, we can't depend on string literals or ctype macros to 136 * tell us anything about network-format data. The rest of the BIND system 137 * is not careful about this, but for some reason, we're doing it right here. 138 */ 139 #define PERIOD 0x2e 140 #define hyphenchar(c) ((c) == 0x2d) 141 #define bslashchar(c) ((c) == 0x5c) 142 #define underscorechar(c) ((c) == 0x5f) 143 #define periodchar(c) ((c) == PERIOD) 144 #define asterchar(c) ((c) == 0x2a) 145 #define alphachar(c) (((c) >= 0x41 && (c) <= 0x5a) \ 146 || ((c) >= 0x61 && (c) <= 0x7a)) 147 #define digitchar(c) ((c) >= 0x30 && (c) <= 0x39) 148 149 #ifdef RES_ENFORCE_RFC1034 150 #define borderchar(c) (alphachar(c) || digitchar(c)) 151 #else 152 #define borderchar(c) (alphachar(c) || digitchar(c) || underscorechar(c)) 153 #endif 154 #define middlechar(c) (borderchar(c) || hyphenchar(c)) 155 #define domainchar(c) ((c) > 0x20 && (c) < 0x7f) 156 157 int 158 res_hnok(const char *dn) { 159 int pch = PERIOD, ch = *dn++; 160 161 while (ch != '\0') { 162 int nch = *dn++; 163 164 if (periodchar(ch)) { 165 (void)NULL; 166 } else if (periodchar(pch)) { 167 if (!borderchar(ch)) 168 return (0); 169 } else if (periodchar(nch) || nch == '\0') { 170 if (!borderchar(ch)) 171 return (0); 172 } else { 173 if (!middlechar(ch)) 174 return (0); 175 } 176 pch = ch, ch = nch; 177 } 178 return (1); 179 } 180 181 /*% 182 * hostname-like (A, MX, WKS) owners can have "*" as their first label 183 * but must otherwise be as a host name. 184 */ 185 int 186 res_ownok(const char *dn) { 187 if (asterchar(dn[0])) { 188 if (periodchar(dn[1])) 189 return (res_hnok(dn+2)); 190 if (dn[1] == '\0') 191 return (1); 192 } 193 return (res_hnok(dn)); 194 } 195 196 /*% 197 * SOA RNAMEs and RP RNAMEs can have any printable character in their first 198 * label, but the rest of the name has to look like a host name. 199 */ 200 int 201 res_mailok(const char *dn) { 202 int ch, escaped = 0; 203 204 /* "." is a valid missing representation */ 205 if (*dn == '\0') 206 return (1); 207 208 /* otherwise <label>.<hostname> */ 209 while ((ch = *dn++) != '\0') { 210 if (!domainchar(ch)) 211 return (0); 212 if (!escaped && periodchar(ch)) 213 break; 214 if (escaped) 215 escaped = 0; 216 else if (bslashchar(ch)) 217 escaped = 1; 218 } 219 if (periodchar(ch)) 220 return (res_hnok(dn)); 221 return (0); 222 } 223 224 /*% 225 * This function is quite liberal, since RFC1034's character sets are only 226 * recommendations. 227 */ 228 int 229 res_dnok(const char *dn) { 230 int ch; 231 232 while ((ch = *dn++) != '\0') 233 if (!domainchar(ch)) 234 return (0); 235 return (1); 236 } 237 238 #ifdef BIND_4_COMPAT 239 /*% 240 * This module must export the following externally-visible symbols: 241 * ___putlong 242 * ___putshort 243 * __getlong 244 * __getshort 245 * Note that one _ comes from C and the others come from us. 246 */ 247 248 #ifdef SOLARIS2 249 #ifdef __putlong 250 #undef __putlong 251 #endif 252 #ifdef __putshort 253 #undef __putshort 254 #endif 255 #pragma weak putlong = __putlong 256 #pragma weak putshort = __putshort 257 #endif /* SOLARIS2 */ 258 259 void __putlong(u_int32_t src, u_char *dst) { ns_put32(src, dst); } 260 void __putshort(u_int16_t src, u_char *dst) { ns_put16(src, dst); } 261 #ifndef __ultrix__ 262 u_int32_t _getlong(const u_char *src) { return (ns_get32(src)); } 263 u_int16_t _getshort(const u_char *src) { return (ns_get16(src)); } 264 #endif /*__ultrix__*/ 265 #endif /*BIND_4_COMPAT*/ 266 267 /* 268 * Weak aliases for applications that use certain private entry points, 269 * and fail to include <resolv.h>. 270 */ 271 #undef dn_comp 272 __weak_reference(__dn_comp, dn_comp); 273 #undef dn_expand 274 __weak_reference(__dn_expand, dn_expand); 275 276 /*! \file */ 277