res_comp.c revision 298830
1178786Skmacy/* 2178786Skmacy * Copyright (c) 1985, 1993 3178786Skmacy * The Regents of the University of California. All rights reserved. 4178786Skmacy * 5178786Skmacy * Redistribution and use in source and binary forms, with or without 6178786Skmacy * modification, are permitted provided that the following conditions 7178786Skmacy * are met: 8178786Skmacy * 1. Redistributions of source code must retain the above copyright 9178786Skmacy * notice, this list of conditions and the following disclaimer. 10178786Skmacy * 2. Redistributions in binary form must reproduce the above copyright 11178786Skmacy * notice, this list of conditions and the following disclaimer in the 12178786Skmacy * documentation and/or other materials provided with the distribution. 13178786Skmacy * 4. Neither the name of the University nor the names of its contributors 14178786Skmacy * may be used to endorse or promote products derived from this software 15178786Skmacy * without specific prior written permission. 16178786Skmacy * 17178786Skmacy * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18178786Skmacy * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19178786Skmacy * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20178786Skmacy * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21178786Skmacy * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22178786Skmacy * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23178786Skmacy * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24178786Skmacy * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25178786Skmacy * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26178786Skmacy * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27178786Skmacy * SUCH DAMAGE. 28178786Skmacy */ 29178786Skmacy 30178786Skmacy/* 31178786Skmacy * Portions Copyright (c) 1993 by Digital Equipment Corporation. 32237263Snp * 33237263Snp * Permission to use, copy, modify, and distribute this software for any 34237263Snp * purpose with or without fee is hereby granted, provided that the above 35178786Skmacy * copyright notice and this permission notice appear in all copies, and that 36178786Skmacy * the name of Digital Equipment Corporation not be used in advertising or 37178786Skmacy * publicity pertaining to distribution of the document or software without 38178786Skmacy * specific, written prior permission. 39178786Skmacy * 40178786Skmacy * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL 41178786Skmacy * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES 42178786Skmacy * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT 43178786Skmacy * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 44178786Skmacy * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 45178786Skmacy * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS 46178786Skmacy * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 47178786Skmacy * SOFTWARE. 48178786Skmacy */ 49178786Skmacy 50178786Skmacy/* 51178786Skmacy * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") 52178786Skmacy * Portions Copyright (c) 1996-1999 by Internet Software Consortium. 53178786Skmacy * 54178786Skmacy * Permission to use, copy, modify, and distribute this software for any 55178786Skmacy * purpose with or without fee is hereby granted, provided that the above 56178786Skmacy * copyright notice and this permission notice appear in all copies. 57178786Skmacy * 58178786Skmacy * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES 59178786Skmacy * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 60178786Skmacy * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR 61178786Skmacy * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 62178786Skmacy * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 63178786Skmacy * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT 64178786Skmacy * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 65178786Skmacy */ 66178786Skmacy 67237263Snp#if defined(LIBC_SCCS) && !defined(lint) 68237263Snpstatic const char sccsid[] = "@(#)res_comp.c 8.1 (Berkeley) 6/4/93"; 69237263Snpstatic const char rcsid[] = "$Id: res_comp.c,v 1.5 2005/07/28 06:51:50 marka Exp $"; 70237263Snp#endif /* LIBC_SCCS and not lint */ 71237263Snp#include <sys/cdefs.h> 72178786Skmacy__FBSDID("$FreeBSD: head/lib/libc/resolv/res_comp.c 298830 2016-04-30 01:24:24Z pfg $"); 73237263Snp 74178786Skmacy#include "port_before.h" 75178786Skmacy#include <sys/param.h> 76178786Skmacy#include <netinet/in.h> 77178786Skmacy#include <arpa/nameser.h> 78178786Skmacy#include <ctype.h> 79178786Skmacy#include <resolv.h> 80178786Skmacy#include <stdio.h> 81178786Skmacy#include <string.h> 82178786Skmacy#include <unistd.h> 83178786Skmacy#include "port_after.h" 84178786Skmacy 85178786Skmacy/*% 86178786Skmacy * Expand compressed domain name 'src' to full domain name. 87178786Skmacy * 88178786Skmacy * \li 'msg' is a pointer to the beginning of the message, 89178786Skmacy * \li 'eom' points to the first location after the message, 90178786Skmacy * \li 'dst' is a pointer to a buffer of size 'dstsiz' for the result. 91178786Skmacy * \li Return size of compressed name or -1 if there was an error. 92178786Skmacy */ 93178786Skmacyint 94178786Skmacydn_expand(const u_char *msg, const u_char *eom, const u_char *src, 95178786Skmacy char *dst, int dstsiz) 96178786Skmacy{ 97178786Skmacy int n = ns_name_uncompress(msg, eom, src, dst, (size_t)dstsiz); 98178786Skmacy 99178786Skmacy if (n > 0 && dst[0] == '.') 100178786Skmacy dst[0] = '\0'; 101178786Skmacy return (n); 102178786Skmacy} 103178786Skmacy 104178786Skmacy/*% 105178786Skmacy * Pack domain name 'exp_dn' in presentation form into 'comp_dn'. 106178786Skmacy * 107178786Skmacy * \li Return the size of the compressed name or -1. 108178786Skmacy * \li 'length' is the size of the array pointed to by 'comp_dn'. 109178786Skmacy */ 110178786Skmacyint 111178786Skmacydn_comp(const char *src, u_char *dst, int dstsiz, 112178786Skmacy u_char **dnptrs, u_char **lastdnptr) 113178786Skmacy{ 114178786Skmacy return (ns_name_compress(src, dst, (size_t)dstsiz, 115178786Skmacy (const u_char **)dnptrs, 116178786Skmacy (const u_char **)lastdnptr)); 117178786Skmacy} 118178786Skmacy 119178786Skmacy/*% 120178786Skmacy * Skip over a compressed domain name. Return the size or -1. 121178786Skmacy */ 122178786Skmacyint 123178786Skmacydn_skipname(const u_char *ptr, const u_char *eom) { 124178786Skmacy const u_char *saveptr = ptr; 125178786Skmacy 126178786Skmacy if (ns_name_skip(&ptr, eom) == -1) 127178786Skmacy return (-1); 128178786Skmacy return (ptr - saveptr); 129178786Skmacy} 130178786Skmacy 131178786Skmacy/*% 132178786Skmacy * Verify that a domain name uses an acceptable character set. 133178786Skmacy * 134178786Skmacy * Note the conspicuous absence of ctype macros in these definitions. On 135178786Skmacy * non-ASCII hosts, we can't depend on string literals or ctype macros to 136178786Skmacy * tell us anything about network-format data. The rest of the BIND system 137178786Skmacy * is not careful about this, but for some reason, we're doing it right here. 138178786Skmacy */ 139178786Skmacy#define PERIOD 0x2e 140178786Skmacy#define hyphenchar(c) ((c) == 0x2d) 141178786Skmacy#define bslashchar(c) ((c) == 0x5c) 142178786Skmacy#define underscorechar(c) ((c) == 0x5f) 143178786Skmacy#define periodchar(c) ((c) == PERIOD) 144178786Skmacy#define asterchar(c) ((c) == 0x2a) 145178786Skmacy#define alphachar(c) (((c) >= 0x41 && (c) <= 0x5a) \ 146178786Skmacy || ((c) >= 0x61 && (c) <= 0x7a)) 147178786Skmacy#define digitchar(c) ((c) >= 0x30 && (c) <= 0x39) 148178786Skmacy 149178786Skmacy#ifdef RES_ENFORCE_RFC1034 150178786Skmacy#define borderchar(c) (alphachar(c) || digitchar(c)) 151178786Skmacy#else 152178786Skmacy#define borderchar(c) (alphachar(c) || digitchar(c) || underscorechar(c)) 153178786Skmacy#endif 154178786Skmacy#define middlechar(c) (borderchar(c) || hyphenchar(c)) 155178786Skmacy#define domainchar(c) ((c) > 0x20 && (c) < 0x7f) 156178786Skmacy 157178786Skmacyint 158178786Skmacyres_hnok(const char *dn) { 159178786Skmacy int pch = PERIOD, ch = *dn++; 160178786Skmacy 161178786Skmacy while (ch != '\0') { 162178786Skmacy int nch = *dn++; 163178786Skmacy 164178786Skmacy if (periodchar(ch)) { 165178786Skmacy (void)NULL; 166178786Skmacy } else if (periodchar(pch)) { 167178786Skmacy if (!borderchar(ch)) 168178786Skmacy return (0); 169178786Skmacy } else if (periodchar(nch) || nch == '\0') { 170178786Skmacy if (!borderchar(ch)) 171178786Skmacy return (0); 172178786Skmacy } else { 173178786Skmacy if (!middlechar(ch)) 174178786Skmacy return (0); 175178786Skmacy } 176178786Skmacy pch = ch, ch = nch; 177178786Skmacy } 178178786Skmacy return (1); 179278886Shselasky} 180178786Skmacy 181178786Skmacy/*% 182178786Skmacy * hostname-like (A, MX, WKS) owners can have "*" as their first label 183178786Skmacy * but must otherwise be as a host name. 184178786Skmacy */ 185178786Skmacyint 186178786Skmacyres_ownok(const char *dn) { 187178786Skmacy if (asterchar(dn[0])) { 188237263Snp if (periodchar(dn[1])) 189237263Snp return (res_hnok(dn+2)); 190278886Shselasky if (dn[1] == '\0') 191178786Skmacy return (1); 192178786Skmacy } 193178786Skmacy return (res_hnok(dn)); 194178786Skmacy} 195178786Skmacy 196178786Skmacy/*% 197178786Skmacy * SOA RNAMEs and RP RNAMEs can have any printable character in their first 198178786Skmacy * label, but the rest of the name has to look like a host name. 199178786Skmacy */ 200178786Skmacyint 201178786Skmacyres_mailok(const char *dn) { 202178786Skmacy int ch, escaped = 0; 203178786Skmacy 204178786Skmacy /* "." is a valid missing representation */ 205178786Skmacy if (*dn == '\0') 206178786Skmacy return (1); 207178786Skmacy 208178786Skmacy /* otherwise <label>.<hostname> */ 209178786Skmacy while ((ch = *dn++) != '\0') { 210178786Skmacy if (!domainchar(ch)) 211178786Skmacy return (0); 212178786Skmacy if (!escaped && periodchar(ch)) 213178786Skmacy break; 214178786Skmacy if (escaped) 215178786Skmacy escaped = 0; 216178786Skmacy else if (bslashchar(ch)) 217178786Skmacy escaped = 1; 218178786Skmacy } 219178786Skmacy if (periodchar(ch)) 220178786Skmacy return (res_hnok(dn)); 221178786Skmacy return (0); 222178786Skmacy} 223178786Skmacy 224178786Skmacy/*% 225237263Snp * This function is quite liberal, since RFC1034's character sets are only 226178786Skmacy * recommendations. 227178786Skmacy */ 228178786Skmacyint 229178786Skmacyres_dnok(const char *dn) { 230178786Skmacy int ch; 231178786Skmacy 232178786Skmacy while ((ch = *dn++) != '\0') 233237263Snp if (!domainchar(ch)) 234237263Snp return (0); 235237263Snp return (1); 236237263Snp} 237237263Snp 238178786Skmacy#ifdef BIND_4_COMPAT 239178786Skmacy/*% 240178786Skmacy * This module must export the following externally-visible symbols: 241178786Skmacy * ___putlong 242178786Skmacy * ___putshort 243178786Skmacy * __getlong 244178786Skmacy * __getshort 245178786Skmacy * Note that one _ comes from C and the others come from us. 246178786Skmacy */ 247178786Skmacy 248178786Skmacy#ifdef SOLARIS2 249178786Skmacy#ifdef __putlong 250178786Skmacy#undef __putlong 251178786Skmacy#endif 252178786Skmacy#ifdef __putshort 253237263Snp#undef __putshort 254237263Snp#endif 255237263Snp#pragma weak putlong = __putlong 256237263Snp#pragma weak putshort = __putshort 257237263Snp#endif /* SOLARIS2 */ 258237263Snp 259237263Snpvoid __putlong(u_int32_t src, u_char *dst) { ns_put32(src, dst); } 260237263Snpvoid __putshort(u_int16_t src, u_char *dst) { ns_put16(src, dst); } 261237263Snp#ifndef __ultrix__ 262237263Snpu_int32_t _getlong(const u_char *src) { return (ns_get32(src)); } 263237263Snpu_int16_t _getshort(const u_char *src) { return (ns_get16(src)); } 264237263Snp#endif /*__ultrix__*/ 265237263Snp#endif /*BIND_4_COMPAT*/ 266237263Snp 267237263Snp/* 268237263Snp * Weak aliases for applications that use certain private entry points, 269237263Snp * and fail to include <resolv.h>. 270178786Skmacy */ 271178786Skmacy#undef dn_comp 272178786Skmacy__weak_reference(__dn_comp, dn_comp); 273178786Skmacy#undef dn_expand 274178786Skmacy__weak_reference(__dn_expand, dn_expand); 275178786Skmacy 276178786Skmacy/*! \file */ 277178786Skmacy