172 lines
6.7 KiB
C++
172 lines
6.7 KiB
C++
/* $NetBSD: res_comp.c,v 1.6 2004/05/22 23:47:09 christos Exp $ */
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/*
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* Copyright (c) 1985, 1993
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* The Regents of the University of California. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the University of
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* California, Berkeley and its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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/*
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* Portions Copyright (c) 1993 by Digital Equipment Corporation.
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*
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* Permission to use, copy, modify, and distribute this software for any
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* purpose with or without fee is hereby granted, provided that the above
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* copyright notice and this permission notice appear in all copies, and that
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* the name of Digital Equipment Corporation not be used in advertising or
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* publicity pertaining to distribution of the document or software without
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* specific, written prior permission.
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*
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* THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
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* WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
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* CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
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* DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
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* PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
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* ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
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* SOFTWARE.
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*/
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/*
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* Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
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* Portions Copyright (c) 1996-1999 by Internet Software Consortium.
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*
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* Permission to use, copy, modify, and distribute this software for any
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* purpose with or without fee is hereby granted, provided that the above
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* copyright notice and this permission notice appear in all copies.
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*
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* THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
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* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
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* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
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* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
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* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
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* OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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*/
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#include "res_comp.h"
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#include <arpa/nameser.h>
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#include <netinet/in.h>
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#include <string.h>
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#include <unistd.h>
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/*
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* Expand compressed domain name 'src' to full domain name.
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* 'msg' is a pointer to the begining of the message,
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* 'eom' points to the first location after the message,
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* 'dst' is a pointer to a buffer of size 'dstsiz' for the result.
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* Return size of compressed name or -1 if there was an error.
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*/
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int dn_expand(const uint8_t* msg, const uint8_t* eom, const uint8_t* src, char* dst, int dstsiz) {
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int n = ns_name_uncompress(msg, eom, src, dst, (size_t) dstsiz);
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if (n > 0 && dst[0] == '.') dst[0] = '\0';
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return n;
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}
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/*
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* Pack domain name 'exp_dn' in presentation form into 'comp_dn'.
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* Return the size of the compressed name or -1.
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* 'length' is the size of the array pointed to by 'comp_dn'.
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*/
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int dn_comp(const char* src, uint8_t* dst, int dstsiz, uint8_t** dnptrs, uint8_t** lastdnptr) {
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return (ns_name_compress(src, dst, (size_t)dstsiz, (const uint8_t**)dnptrs,
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(const uint8_t**)lastdnptr));
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}
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/*
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* Skip over a compressed domain name. Return the size or -1.
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*/
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int dn_skipname(const uint8_t* ptr, const uint8_t* eom) {
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const uint8_t* saveptr = ptr;
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if (ns_name_skip(&ptr, eom) == -1) return (-1);
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return (ptr - saveptr);
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}
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/*
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* Verify that a domain name uses an acceptable character set.
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*/
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/*
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* Note the conspicuous absence of ctype macros in these definitions. On
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* non-ASCII hosts, we can't depend on string literals or ctype macros to
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* tell us anything about network-format data. The rest of the BIND system
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* is not careful about this, but for some reason, we're doing it right here.
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*/
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/* BIONIC: We also accept underscores in the middle of labels.
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* This extension is needed to make resolution on some VPN networks
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* work properly.
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*/
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#define PERIOD 0x2e
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#define hyphenchar(c) ((c) == 0x2d)
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#define bslashchar(c) ((c) == 0x5c)
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#define periodchar(c) ((c) == PERIOD)
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#define asterchar(c) ((c) == 0x2a)
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#define alphachar(c) (((c) >= 0x41 && (c) <= 0x5a) || ((c) >= 0x61 && (c) <= 0x7a))
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#define digitchar(c) ((c) >= 0x30 && (c) <= 0x39)
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#define underscorechar(c) ((c) == 0x5f)
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#define borderchar(c) (alphachar(c) || digitchar(c))
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#define middlechar(c) (borderchar(c) || hyphenchar(c) || underscorechar(c))
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#define domainchar(c) ((c) > 0x20 && (c) < 0x7f)
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bool res_hnok(const char* dn) {
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char pch = PERIOD, ch = *dn++;
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while (ch != '\0') {
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char nch = *dn++;
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if (periodchar(ch)) {
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;
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} else if (periodchar(pch) || periodchar(nch) || nch == '\0') {
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if (!borderchar(ch)) return false;
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} else {
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if (!middlechar(ch)) return false;
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}
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pch = ch, ch = nch;
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}
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return true;
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}
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/*
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* This function is quite liberal, since RFC 1034's character sets are only
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* recommendations.
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*/
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bool res_dnok(const char* dn) {
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char ch;
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while ((ch = *dn++) != '\0')
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if (!domainchar(ch)) return false;
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return true;
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}
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