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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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/* |
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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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/* |
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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 INTERNET SOFTWARE CONSORTIUM DISCLAIMS |
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* ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES |
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* OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE |
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* CONSORTIUM 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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/* Original copyright ISC as above. |
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* Code modified specifically for ircd use from the following orginal files |
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* in bind ... |
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* |
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* res_comp.c |
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* ns_name.c |
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* ns_netint.c |
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* res_init.c |
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* |
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* - Dianora |
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*/ |
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|
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#include "stdinc.h" |
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#include "ircd_defs.h" |
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#include "irc_res.h" |
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#include "irc_reslib.h" |
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#include "fileio.h" |
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#include "irc_string.h" |
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#include "irc_getaddrinfo.h" |
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|
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#define NS_TYPE_ELT 0x40 /* EDNS0 extended label type */ |
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#define DNS_LABELTYPE_BITSTRING 0x41 |
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#define MAXLINE 128 |
94 |
|
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/* $Id$ */ |
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|
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struct irc_ssaddr irc_nsaddr_list[IRCD_MAXNS]; |
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int irc_nscount = 0; |
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|
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static const char digitvalue[256] = { |
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-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*16*/ |
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-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*32*/ |
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-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*48*/ |
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0, 1, 2, 3, 4, 5, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1, /*64*/ |
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-1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*80*/ |
106 |
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*96*/ |
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-1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*112*/ |
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-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*128*/ |
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-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, |
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-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, |
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-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, |
112 |
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, |
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-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, |
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-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, |
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-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, |
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-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*256*/ |
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}; |
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|
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static int parse_resvconf(void); |
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static void add_nameserver(char *arg); |
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|
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static const char digits[] = "0123456789"; |
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static int labellen(const unsigned char *lp); |
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static int special(int ch); |
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static int printable(int ch); |
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static int irc_decode_bitstring(const unsigned char **cpp, char *dn, const char *eom); |
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static int irc_ns_name_compress(const char *src, unsigned char *dst, size_t dstsiz, |
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const unsigned char **dnptrs, const unsigned char **lastdnptr); |
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static int irc_dn_find(const unsigned char *, const unsigned char *, const unsigned char * const *, |
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const unsigned char * const *); |
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static int irc_encode_bitsring(const char **, const char *, unsigned char **, unsigned char **, |
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const unsigned char *); |
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static int irc_ns_name_uncompress(const unsigned char *, const unsigned char *, |
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const unsigned char *, char *, size_t); |
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static int irc_ns_name_unpack(const unsigned char *, const unsigned char *, |
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const unsigned char *, unsigned char *, |
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size_t); |
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static int irc_ns_name_ntop(const unsigned char *, char *, size_t); |
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static int irc_ns_name_skip(const unsigned char **, const unsigned char *); |
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static int mklower(int ch); |
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|
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int |
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irc_res_init(void) |
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{ |
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irc_nscount = 0; |
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memset(irc_nsaddr_list, 0, sizeof(irc_nsaddr_list)); |
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|
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return parse_resvconf(); |
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} |
150 |
|
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/* parse_resvconf() |
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* |
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* inputs - NONE |
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* output - -1 if failure 0 if success |
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* side effects - fills in irc_nsaddr_list |
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*/ |
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static int |
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parse_resvconf(void) |
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{ |
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char *p; |
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char *opt; |
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char *arg; |
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char input[MAXLINE]; |
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FBFILE *file; |
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|
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/* XXX "/etc/resolv.conf" should be from a define in config.h perhaps |
167 |
* for cygwin support etc. this hardcodes it to unix for now -db |
168 |
*/ |
169 |
if ((file = fbopen("/etc/resolv.conf", "r")) == NULL) |
170 |
return -1; |
171 |
|
172 |
while (fbgets(input, sizeof(input), file) != NULL) |
173 |
{ |
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/* blow away any newline */ |
175 |
if ((p = strpbrk(input, "\r\n")) != NULL) |
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*p = '\0'; |
177 |
|
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p = input; |
179 |
|
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/* skip until something thats not a space is seen */ |
181 |
while (IsSpace(*p)) |
182 |
++p; |
183 |
|
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/* if at this point, have a '\0' then continue */ |
185 |
if (*p == '\0') |
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continue; |
187 |
|
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/* Ignore comment lines immediately */ |
189 |
if (*p == ';' || *p == '#') |
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continue; |
191 |
|
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/* skip until a space is found */ |
193 |
opt = p; |
194 |
while (!IsSpace(*p) && *p) |
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++p; |
196 |
|
197 |
if (*p == '\0') |
198 |
continue; /* no arguments?.. ignore this line */ |
199 |
|
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/* blow away the space character */ |
201 |
*p++ = '\0'; |
202 |
|
203 |
/* skip these spaces that are before the argument */ |
204 |
while (IsSpace(*p)) |
205 |
++p; |
206 |
|
207 |
/* Now arg should be right where p is pointing */ |
208 |
arg = p; |
209 |
|
210 |
if ((p = strpbrk(arg, " \t")) != NULL) |
211 |
*p = '\0'; /* take the first word */ |
212 |
|
213 |
if (irccmp(opt, "nameserver") == 0) |
214 |
add_nameserver(arg); |
215 |
} |
216 |
|
217 |
fbclose(file); |
218 |
return 0; |
219 |
} |
220 |
|
221 |
/* add_nameserver() |
222 |
* |
223 |
* input - either an IPV4 address in dotted quad |
224 |
* or an IPV6 address in : format |
225 |
* output - NONE |
226 |
* side effects - entry in irc_nsaddr_list is filled in as needed |
227 |
*/ |
228 |
static void |
229 |
add_nameserver(char *arg) |
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{ |
231 |
struct addrinfo hints, *res; |
232 |
/* Done max number of nameservers? */ |
233 |
if ((irc_nscount) >= IRCD_MAXNS) |
234 |
return; |
235 |
|
236 |
memset(&hints, 0, sizeof(hints)); |
237 |
hints.ai_family = PF_UNSPEC; |
238 |
hints.ai_socktype = SOCK_DGRAM; |
239 |
hints.ai_flags = AI_PASSIVE | AI_NUMERICHOST; |
240 |
|
241 |
if (irc_getaddrinfo(arg, "domain", &hints, &res)) |
242 |
return; |
243 |
|
244 |
if (res == NULL) |
245 |
return; |
246 |
|
247 |
memcpy(&irc_nsaddr_list[irc_nscount].ss, res->ai_addr, res->ai_addrlen); |
248 |
irc_nsaddr_list[irc_nscount].ss_len = res->ai_addrlen; |
249 |
irc_nscount++; |
250 |
irc_freeaddrinfo(res); |
251 |
} |
252 |
|
253 |
/* |
254 |
* Expand compressed domain name 'comp_dn' to full domain name. |
255 |
* 'msg' is a pointer to the begining of the message, |
256 |
* 'eomorig' points to the first location after the message, |
257 |
* 'exp_dn' is a pointer to a buffer of size 'length' for the result. |
258 |
* Return size of compressed name or -1 if there was an error. |
259 |
*/ |
260 |
int |
261 |
irc_dn_expand(const unsigned char *msg, const unsigned char *eom, |
262 |
const unsigned char *src, char *dst, int dstsiz) |
263 |
{ |
264 |
int n = irc_ns_name_uncompress(msg, eom, src, dst, (size_t)dstsiz); |
265 |
|
266 |
if (n > 0 && dst[0] == '.') |
267 |
dst[0] = '\0'; |
268 |
return(n); |
269 |
} /*2*/ |
270 |
|
271 |
/* |
272 |
* irc_ns_name_uncompress(msg, eom, src, dst, dstsiz) |
273 |
* Expand compressed domain name to presentation format. |
274 |
* return: |
275 |
* Number of bytes read out of `src', or -1 (with errno set). |
276 |
* note: |
277 |
* Root domain returns as "." not "". |
278 |
*/ |
279 |
static int |
280 |
irc_ns_name_uncompress(const unsigned char *msg, const unsigned char *eom, |
281 |
const unsigned char *src, char *dst, size_t dstsiz) |
282 |
{ |
283 |
unsigned char tmp[NS_MAXCDNAME]; |
284 |
int n; |
285 |
|
286 |
if ((n = irc_ns_name_unpack(msg, eom, src, tmp, sizeof tmp)) == -1) |
287 |
return(-1); |
288 |
if (irc_ns_name_ntop(tmp, dst, dstsiz) == -1) |
289 |
return(-1); |
290 |
return(n); |
291 |
} /*2*/ |
292 |
|
293 |
/* |
294 |
* irc_ns_name_unpack(msg, eom, src, dst, dstsiz) |
295 |
* Unpack a domain name from a message, source may be compressed. |
296 |
* return: |
297 |
* -1 if it fails, or consumed octets if it succeeds. |
298 |
*/ |
299 |
static int |
300 |
irc_ns_name_unpack(const unsigned char *msg, const unsigned char *eom, |
301 |
const unsigned char *src, unsigned char *dst, |
302 |
size_t dstsiz) |
303 |
{ |
304 |
const unsigned char *srcp, *dstlim; |
305 |
unsigned char *dstp; |
306 |
int n, len, checked, l; |
307 |
|
308 |
len = -1; |
309 |
checked = 0; |
310 |
dstp = dst; |
311 |
srcp = src; |
312 |
dstlim = dst + dstsiz; |
313 |
if (srcp < msg || srcp >= eom) { |
314 |
errno = EMSGSIZE; |
315 |
return (-1); |
316 |
} |
317 |
/* Fetch next label in domain name. */ |
318 |
while ((n = *srcp++) != 0) { |
319 |
/* Check for indirection. */ |
320 |
switch (n & NS_CMPRSFLGS) { |
321 |
case 0: |
322 |
case NS_TYPE_ELT: |
323 |
/* Limit checks. */ |
324 |
if ((l = labellen(srcp - 1)) < 0) { |
325 |
errno = EMSGSIZE; |
326 |
return(-1); |
327 |
} |
328 |
if (dstp + l + 1 >= dstlim || srcp + l >= eom) { |
329 |
errno = EMSGSIZE; |
330 |
return (-1); |
331 |
} |
332 |
checked += l + 1; |
333 |
*dstp++ = n; |
334 |
memcpy(dstp, srcp, l); |
335 |
dstp += l; |
336 |
srcp += l; |
337 |
break; |
338 |
|
339 |
case NS_CMPRSFLGS: |
340 |
if (srcp >= eom) { |
341 |
errno = EMSGSIZE; |
342 |
return (-1); |
343 |
} |
344 |
if (len < 0) |
345 |
len = srcp - src + 1; |
346 |
srcp = msg + (((n & 0x3f) << 8) | (*srcp & 0xff)); |
347 |
if (srcp < msg || srcp >= eom) { /* Out of range. */ |
348 |
errno = EMSGSIZE; |
349 |
return (-1); |
350 |
} |
351 |
checked += 2; |
352 |
/* |
353 |
* Check for loops in the compressed name; |
354 |
* if we've looked at the whole message, |
355 |
* there must be a loop. |
356 |
*/ |
357 |
if (checked >= eom - msg) { |
358 |
errno = EMSGSIZE; |
359 |
return (-1); |
360 |
} |
361 |
break; |
362 |
|
363 |
default: |
364 |
errno = EMSGSIZE; |
365 |
return (-1); /* flag error */ |
366 |
} |
367 |
} |
368 |
*dstp = '\0'; |
369 |
if (len < 0) |
370 |
len = srcp - src; |
371 |
return (len); |
372 |
} /*2*/ |
373 |
|
374 |
/* |
375 |
* irc_ns_name_ntop(src, dst, dstsiz) |
376 |
* Convert an encoded domain name to printable ascii as per RFC1035. |
377 |
* return: |
378 |
* Number of bytes written to buffer, or -1 (with errno set) |
379 |
* notes: |
380 |
* The root is returned as "." |
381 |
* All other domains are returned in non absolute form |
382 |
*/ |
383 |
static int |
384 |
irc_ns_name_ntop(const unsigned char *src, char *dst, size_t dstsiz) |
385 |
{ |
386 |
const unsigned char *cp; |
387 |
char *dn, *eom; |
388 |
unsigned char c; |
389 |
unsigned int n; |
390 |
int l; |
391 |
|
392 |
cp = src; |
393 |
dn = dst; |
394 |
eom = dst + dstsiz; |
395 |
|
396 |
while ((n = *cp++) != 0) { |
397 |
if ((n & NS_CMPRSFLGS) == NS_CMPRSFLGS) { |
398 |
/* Some kind of compression pointer. */ |
399 |
errno = EMSGSIZE; |
400 |
return (-1); |
401 |
} |
402 |
if (dn != dst) { |
403 |
if (dn >= eom) { |
404 |
errno = EMSGSIZE; |
405 |
return (-1); |
406 |
} |
407 |
*dn++ = '.'; |
408 |
} |
409 |
if ((l = labellen((cp - 1))) < 0) { |
410 |
errno = EMSGSIZE; /* XXX */ |
411 |
return(-1); |
412 |
} |
413 |
if (dn + l >= eom) { |
414 |
errno = EMSGSIZE; |
415 |
return (-1); |
416 |
} |
417 |
if ((n & NS_CMPRSFLGS) == NS_TYPE_ELT) { |
418 |
int m; |
419 |
|
420 |
if (n != DNS_LABELTYPE_BITSTRING) { |
421 |
/* XXX: labellen should reject this case */ |
422 |
errno = EINVAL; |
423 |
return(-1); |
424 |
} |
425 |
if ((m = irc_decode_bitstring(&cp, dn, eom)) < 0) |
426 |
{ |
427 |
errno = EMSGSIZE; |
428 |
return(-1); |
429 |
} |
430 |
dn += m; |
431 |
continue; |
432 |
} |
433 |
for ((void)NULL; l > 0; l--) { |
434 |
c = *cp++; |
435 |
if (special(c)) { |
436 |
if (dn + 1 >= eom) { |
437 |
errno = EMSGSIZE; |
438 |
return (-1); |
439 |
} |
440 |
*dn++ = '\\'; |
441 |
*dn++ = (char)c; |
442 |
} else if (!printable(c)) { |
443 |
if (dn + 3 >= eom) { |
444 |
errno = EMSGSIZE; |
445 |
return (-1); |
446 |
} |
447 |
*dn++ = '\\'; |
448 |
*dn++ = digits[c / 100]; |
449 |
*dn++ = digits[(c % 100) / 10]; |
450 |
*dn++ = digits[c % 10]; |
451 |
} else { |
452 |
if (dn >= eom) { |
453 |
errno = EMSGSIZE; |
454 |
return (-1); |
455 |
} |
456 |
*dn++ = (char)c; |
457 |
} |
458 |
} |
459 |
} |
460 |
if (dn == dst) { |
461 |
if (dn >= eom) { |
462 |
errno = EMSGSIZE; |
463 |
return (-1); |
464 |
} |
465 |
*dn++ = '.'; |
466 |
} |
467 |
if (dn >= eom) { |
468 |
errno = EMSGSIZE; |
469 |
return (-1); |
470 |
} |
471 |
*dn++ = '\0'; |
472 |
return (dn - dst); |
473 |
} /*2*/ |
474 |
|
475 |
/* |
476 |
* Skip over a compressed domain name. Return the size or -1. |
477 |
*/ |
478 |
int |
479 |
irc_dn_skipname(const unsigned char *ptr, const unsigned char *eom) { |
480 |
const unsigned char *saveptr = ptr; |
481 |
|
482 |
if (irc_ns_name_skip(&ptr, eom) == -1) |
483 |
return(-1); |
484 |
return(ptr - saveptr); |
485 |
} /*2*/ |
486 |
|
487 |
/* |
488 |
* ns_name_skip(ptrptr, eom) |
489 |
* Advance *ptrptr to skip over the compressed name it points at. |
490 |
* return: |
491 |
* 0 on success, -1 (with errno set) on failure. |
492 |
*/ |
493 |
static int |
494 |
irc_ns_name_skip(const unsigned char **ptrptr, const unsigned char *eom) |
495 |
{ |
496 |
const unsigned char *cp; |
497 |
unsigned int n; |
498 |
int l; |
499 |
|
500 |
cp = *ptrptr; |
501 |
|
502 |
while (cp < eom && (n = *cp++) != 0) |
503 |
{ |
504 |
/* Check for indirection. */ |
505 |
switch (n & NS_CMPRSFLGS) |
506 |
{ |
507 |
case 0: /* normal case, n == len */ |
508 |
cp += n; |
509 |
continue; |
510 |
case NS_TYPE_ELT: /* EDNS0 extended label */ |
511 |
if ((l = labellen(cp - 1)) < 0) |
512 |
{ |
513 |
errno = EMSGSIZE; /* XXX */ |
514 |
return(-1); |
515 |
} |
516 |
|
517 |
cp += l; |
518 |
continue; |
519 |
case NS_CMPRSFLGS: /* indirection */ |
520 |
cp++; |
521 |
break; |
522 |
default: /* illegal type */ |
523 |
errno = EMSGSIZE; |
524 |
return(-1); |
525 |
} |
526 |
|
527 |
break; |
528 |
} |
529 |
|
530 |
if (cp > eom) |
531 |
{ |
532 |
errno = EMSGSIZE; |
533 |
return (-1); |
534 |
} |
535 |
|
536 |
*ptrptr = cp; |
537 |
return(0); |
538 |
} /*2*/ |
539 |
|
540 |
unsigned int |
541 |
irc_ns_get16(const unsigned char *src) |
542 |
{ |
543 |
unsigned int dst; |
544 |
|
545 |
IRC_NS_GET16(dst, src); |
546 |
return(dst); |
547 |
} |
548 |
|
549 |
unsigned long |
550 |
irc_ns_get32(const unsigned char *src) |
551 |
{ |
552 |
unsigned long dst; |
553 |
|
554 |
IRC_NS_GET32(dst, src); |
555 |
return(dst); |
556 |
} |
557 |
|
558 |
void |
559 |
irc_ns_put16(unsigned int src, unsigned char *dst) |
560 |
{ |
561 |
IRC_NS_PUT16(src, dst); |
562 |
} |
563 |
|
564 |
void |
565 |
irc_ns_put32(unsigned long src, unsigned char *dst) |
566 |
{ |
567 |
IRC_NS_PUT32(src, dst); |
568 |
} |
569 |
|
570 |
/* From ns_name.c */ |
571 |
|
572 |
/* |
573 |
* special(ch) |
574 |
* Thinking in noninternationalized USASCII (per the DNS spec), |
575 |
* is this characted special ("in need of quoting") ? |
576 |
* return: |
577 |
* boolean. |
578 |
*/ |
579 |
static int |
580 |
special(int ch) |
581 |
{ |
582 |
switch (ch) |
583 |
{ |
584 |
case 0x22: /* '"' */ |
585 |
case 0x2E: /* '.' */ |
586 |
case 0x3B: /* ';' */ |
587 |
case 0x5C: /* '\\' */ |
588 |
case 0x28: /* '(' */ |
589 |
case 0x29: /* ')' */ |
590 |
/* Special modifiers in zone files. */ |
591 |
case 0x40: /* '@' */ |
592 |
case 0x24: /* '$' */ |
593 |
return(1); |
594 |
default: |
595 |
return(0); |
596 |
} |
597 |
} /*2*/ |
598 |
|
599 |
static int |
600 |
labellen(const unsigned char *lp) |
601 |
{ |
602 |
int bitlen; |
603 |
unsigned char l = *lp; |
604 |
|
605 |
if ((l & NS_CMPRSFLGS) == NS_CMPRSFLGS) |
606 |
{ |
607 |
/* should be avoided by the caller */ |
608 |
return(-1); |
609 |
} |
610 |
|
611 |
if ((l & NS_CMPRSFLGS) == NS_TYPE_ELT) |
612 |
{ |
613 |
if (l == DNS_LABELTYPE_BITSTRING) |
614 |
{ |
615 |
if ((bitlen = *(lp + 1)) == 0) |
616 |
bitlen = 256; |
617 |
return((bitlen + 7 ) / 8 + 1); |
618 |
} |
619 |
|
620 |
return(-1); /* unknwon ELT */ |
621 |
} |
622 |
|
623 |
return(l); |
624 |
} /*2*/ |
625 |
|
626 |
|
627 |
/* |
628 |
* printable(ch) |
629 |
* Thinking in noninternationalized USASCII (per the DNS spec), |
630 |
* is this character visible and not a space when printed ? |
631 |
* return: |
632 |
* boolean. |
633 |
*/ |
634 |
static int |
635 |
printable(int ch) |
636 |
{ |
637 |
return(ch > 0x20 && ch < 0x7f); |
638 |
} /*2*/ |
639 |
|
640 |
static int |
641 |
irc_decode_bitstring(const unsigned char **cpp, char *dn, const char *eom) |
642 |
{ |
643 |
const unsigned char *cp = *cpp; |
644 |
char *beg = dn, tc; |
645 |
int b, blen, plen; |
646 |
|
647 |
if ((blen = (*cp & 0xff)) == 0) |
648 |
blen = 256; |
649 |
plen = (blen + 3) / 4; |
650 |
plen += sizeof("\\[x/]") + (blen > 99 ? 3 : (blen > 9) ? 2 : 1); |
651 |
if (dn + plen >= eom) |
652 |
return(-1); |
653 |
|
654 |
cp++; |
655 |
dn += sprintf(dn, "\\[x"); |
656 |
for (b = blen; b > 7; b -= 8, cp++) |
657 |
dn += sprintf(dn, "%02x", *cp & 0xff); |
658 |
if (b > 4) { |
659 |
tc = *cp++; |
660 |
dn += sprintf(dn, "%02x", tc & (0xff << (8 - b))); |
661 |
} else if (b > 0) { |
662 |
tc = *cp++; |
663 |
dn += sprintf(dn, "%1x", |
664 |
((tc >> 4) & 0x0f) & (0x0f << (4 - b))); |
665 |
} |
666 |
dn += sprintf(dn, "/%d]", blen); |
667 |
|
668 |
*cpp = cp; |
669 |
return(dn - beg); |
670 |
} /*2*/ |
671 |
|
672 |
/* |
673 |
* irc_ns_name_pton(src, dst, dstsiz) |
674 |
* Convert a ascii string into an encoded domain name as per RFC1035. |
675 |
* return: |
676 |
* -1 if it fails |
677 |
* 1 if string was fully qualified |
678 |
* 0 is string was not fully qualified |
679 |
* notes: |
680 |
* Enforces label and domain length limits. |
681 |
*/ |
682 |
static int |
683 |
irc_ns_name_pton(const char *src, unsigned char *dst, size_t dstsiz) |
684 |
{ |
685 |
unsigned char *label, *bp, *eom; |
686 |
char *cp; |
687 |
int c, n, escaped, e = 0; |
688 |
|
689 |
escaped = 0; |
690 |
bp = dst; |
691 |
eom = dst + dstsiz; |
692 |
label = bp++; |
693 |
|
694 |
|
695 |
while ((c = *src++) != 0) { |
696 |
if (escaped) { |
697 |
if (c == '[') { /* start a bit string label */ |
698 |
if ((cp = strchr(src, ']')) == NULL) { |
699 |
errno = EINVAL; /* ??? */ |
700 |
return(-1); |
701 |
} |
702 |
if ((e = irc_encode_bitsring(&src, |
703 |
cp + 2, |
704 |
&label, |
705 |
&bp, |
706 |
eom)) |
707 |
!= 0) { |
708 |
errno = e; |
709 |
return(-1); |
710 |
} |
711 |
escaped = 0; |
712 |
label = bp++; |
713 |
if ((c = *src++) == 0) |
714 |
goto done; |
715 |
else if (c != '.') { |
716 |
errno = EINVAL; |
717 |
return(-1); |
718 |
} |
719 |
continue; |
720 |
} |
721 |
else if ((cp = strchr(digits, c)) != NULL) { |
722 |
n = (cp - digits) * 100; |
723 |
if ((c = *src++) == 0 || |
724 |
(cp = strchr(digits, c)) == NULL) { |
725 |
errno = EMSGSIZE; |
726 |
return (-1); |
727 |
} |
728 |
n += (cp - digits) * 10; |
729 |
if ((c = *src++) == 0 || |
730 |
(cp = strchr(digits, c)) == NULL) { |
731 |
errno = EMSGSIZE; |
732 |
return (-1); |
733 |
} |
734 |
n += (cp - digits); |
735 |
if (n > 255) { |
736 |
errno = EMSGSIZE; |
737 |
return (-1); |
738 |
} |
739 |
c = n; |
740 |
} |
741 |
escaped = 0; |
742 |
} else if (c == '\\') { |
743 |
escaped = 1; |
744 |
continue; |
745 |
} else if (c == '.') { |
746 |
c = (bp - label - 1); |
747 |
if ((c & NS_CMPRSFLGS) != 0) { /* Label too big. */ |
748 |
errno = EMSGSIZE; |
749 |
return (-1); |
750 |
} |
751 |
if (label >= eom) { |
752 |
errno = EMSGSIZE; |
753 |
return (-1); |
754 |
} |
755 |
*label = c; |
756 |
/* Fully qualified ? */ |
757 |
if (*src == '\0') { |
758 |
if (c != 0) { |
759 |
if (bp >= eom) { |
760 |
errno = EMSGSIZE; |
761 |
return (-1); |
762 |
} |
763 |
*bp++ = '\0'; |
764 |
} |
765 |
if ((bp - dst) > NS_MAXCDNAME) { |
766 |
errno = EMSGSIZE; |
767 |
return (-1); |
768 |
} |
769 |
return (1); |
770 |
} |
771 |
if (c == 0 || *src == '.') { |
772 |
errno = EMSGSIZE; |
773 |
return (-1); |
774 |
} |
775 |
label = bp++; |
776 |
continue; |
777 |
} |
778 |
if (bp >= eom) { |
779 |
errno = EMSGSIZE; |
780 |
return (-1); |
781 |
} |
782 |
*bp++ = (unsigned char)c; |
783 |
} |
784 |
c = (bp - label - 1); |
785 |
if ((c & NS_CMPRSFLGS) != 0) { /* Label too big. */ |
786 |
errno = EMSGSIZE; |
787 |
return (-1); |
788 |
} |
789 |
done: |
790 |
if (label >= eom) { |
791 |
errno = EMSGSIZE; |
792 |
return (-1); |
793 |
} |
794 |
*label = c; |
795 |
if (c != 0) { |
796 |
if (bp >= eom) { |
797 |
errno = EMSGSIZE; |
798 |
return (-1); |
799 |
} |
800 |
*bp++ = 0; |
801 |
} |
802 |
|
803 |
if ((bp - dst) > NS_MAXCDNAME) |
804 |
{ /* src too big */ |
805 |
errno = EMSGSIZE; |
806 |
return (-1); |
807 |
} |
808 |
|
809 |
return (0); |
810 |
} /*2*/ |
811 |
|
812 |
/* |
813 |
* irc_ns_name_pack(src, dst, dstsiz, dnptrs, lastdnptr) |
814 |
* Pack domain name 'domain' into 'comp_dn'. |
815 |
* return: |
816 |
* Size of the compressed name, or -1. |
817 |
* notes: |
818 |
* 'dnptrs' is an array of pointers to previous compressed names. |
819 |
* dnptrs[0] is a pointer to the beginning of the message. The array |
820 |
* ends with NULL. |
821 |
* 'lastdnptr' is a pointer to the end of the array pointed to |
822 |
* by 'dnptrs'. |
823 |
* Side effects: |
824 |
* The list of pointers in dnptrs is updated for labels inserted into |
825 |
* the message as we compress the name. If 'dnptr' is NULL, we don't |
826 |
* try to compress names. If 'lastdnptr' is NULL, we don't update the |
827 |
* list. |
828 |
*/ |
829 |
static int |
830 |
irc_ns_name_pack(const unsigned char *src, unsigned char *dst, int dstsiz, |
831 |
const unsigned char **dnptrs, const unsigned char **lastdnptr) |
832 |
{ |
833 |
unsigned char *dstp; |
834 |
const unsigned char **cpp, **lpp, *eob, *msg; |
835 |
const unsigned char *srcp; |
836 |
int n, l, first = 1; |
837 |
|
838 |
srcp = src; |
839 |
dstp = dst; |
840 |
eob = dstp + dstsiz; |
841 |
lpp = cpp = NULL; |
842 |
if (dnptrs != NULL) { |
843 |
if ((msg = *dnptrs++) != NULL) { |
844 |
for (cpp = dnptrs; *cpp != NULL; cpp++) |
845 |
(void)NULL; |
846 |
lpp = cpp; /* end of list to search */ |
847 |
} |
848 |
} else |
849 |
msg = NULL; |
850 |
|
851 |
/* make sure the domain we are about to add is legal */ |
852 |
l = 0; |
853 |
do { |
854 |
int l0; |
855 |
|
856 |
n = *srcp; |
857 |
if ((n & NS_CMPRSFLGS) == NS_CMPRSFLGS) { |
858 |
errno = EMSGSIZE; |
859 |
return (-1); |
860 |
} |
861 |
if ((l0 = labellen(srcp)) < 0) { |
862 |
errno = EINVAL; |
863 |
return(-1); |
864 |
} |
865 |
l += l0 + 1; |
866 |
if (l > NS_MAXCDNAME) { |
867 |
errno = EMSGSIZE; |
868 |
return (-1); |
869 |
} |
870 |
srcp += l0 + 1; |
871 |
} while (n != 0); |
872 |
|
873 |
/* from here on we need to reset compression pointer array on error */ |
874 |
srcp = src; |
875 |
do { |
876 |
/* Look to see if we can use pointers. */ |
877 |
n = *srcp; |
878 |
if (n != 0 && msg != NULL) { |
879 |
l = irc_dn_find(srcp, msg, (const unsigned char * const *)dnptrs, |
880 |
(const unsigned char * const *)lpp); |
881 |
if (l >= 0) { |
882 |
if (dstp + 1 >= eob) { |
883 |
goto cleanup; |
884 |
} |
885 |
*dstp++ = (l >> 8) | NS_CMPRSFLGS; |
886 |
*dstp++ = l % 256; |
887 |
return (dstp - dst); |
888 |
} |
889 |
/* Not found, save it. */ |
890 |
if (lastdnptr != NULL && cpp < lastdnptr - 1 && |
891 |
(dstp - msg) < 0x4000 && first) { |
892 |
*cpp++ = dstp; |
893 |
*cpp = NULL; |
894 |
first = 0; |
895 |
} |
896 |
} |
897 |
/* copy label to buffer */ |
898 |
if ((n & NS_CMPRSFLGS) == NS_CMPRSFLGS) { |
899 |
/* Should not happen. */ |
900 |
goto cleanup; |
901 |
} |
902 |
n = labellen(srcp); |
903 |
if (dstp + 1 + n >= eob) { |
904 |
goto cleanup; |
905 |
} |
906 |
memcpy(dstp, srcp, n + 1); |
907 |
srcp += n + 1; |
908 |
dstp += n + 1; |
909 |
} while (n != 0); |
910 |
|
911 |
if (dstp > eob) { |
912 |
cleanup: |
913 |
if (msg != NULL) |
914 |
*lpp = NULL; |
915 |
errno = EMSGSIZE; |
916 |
return (-1); |
917 |
} |
918 |
return(dstp - dst); |
919 |
} /*2*/ |
920 |
|
921 |
static int |
922 |
irc_ns_name_compress(const char *src, unsigned char *dst, size_t dstsiz, |
923 |
const unsigned char **dnptrs, const unsigned char **lastdnptr) |
924 |
{ |
925 |
unsigned char tmp[NS_MAXCDNAME]; |
926 |
|
927 |
if (irc_ns_name_pton(src, tmp, sizeof tmp) == -1) |
928 |
return(-1); |
929 |
return(irc_ns_name_pack(tmp, dst, dstsiz, dnptrs, lastdnptr)); |
930 |
} |
931 |
|
932 |
static int |
933 |
irc_encode_bitsring(const char **bp, const char *end, unsigned char **labelp, |
934 |
unsigned char **dst, const unsigned char *eom) |
935 |
{ |
936 |
int afterslash = 0; |
937 |
const char *cp = *bp; |
938 |
unsigned char *tp; |
939 |
char c; |
940 |
const char *beg_blen; |
941 |
char *end_blen = NULL; |
942 |
int value = 0, count = 0, tbcount = 0, blen = 0; |
943 |
|
944 |
beg_blen = end_blen = NULL; |
945 |
|
946 |
/* a bitstring must contain at least 2 characters */ |
947 |
if (end - cp < 2) |
948 |
return(EINVAL); |
949 |
|
950 |
/* XXX: currently, only hex strings are supported */ |
951 |
if (*cp++ != 'x') |
952 |
return(EINVAL); |
953 |
if (!isxdigit((*cp) & 0xff)) /* reject '\[x/BLEN]' */ |
954 |
return(EINVAL); |
955 |
|
956 |
for (tp = *dst + 1; cp < end && tp < eom; cp++) { |
957 |
switch((c = *cp)) { |
958 |
case ']': /* end of the bitstring */ |
959 |
if (afterslash) { |
960 |
if (beg_blen == NULL) |
961 |
return(EINVAL); |
962 |
blen = (int)strtol(beg_blen, &end_blen, 10); |
963 |
if (*end_blen != ']') |
964 |
return(EINVAL); |
965 |
} |
966 |
if (count) |
967 |
*tp++ = ((value << 4) & 0xff); |
968 |
cp++; /* skip ']' */ |
969 |
goto done; |
970 |
case '/': |
971 |
afterslash = 1; |
972 |
break; |
973 |
default: |
974 |
if (afterslash) { |
975 |
if (!isdigit(c&0xff)) |
976 |
return(EINVAL); |
977 |
if (beg_blen == NULL) { |
978 |
|
979 |
if (c == '0') { |
980 |
/* blen never begings with 0 */ |
981 |
return(EINVAL); |
982 |
} |
983 |
beg_blen = cp; |
984 |
} |
985 |
} else { |
986 |
if (!isxdigit(c&0xff)) |
987 |
return(EINVAL); |
988 |
value <<= 4; |
989 |
value += digitvalue[(int)c]; |
990 |
count += 4; |
991 |
tbcount += 4; |
992 |
if (tbcount > 256) |
993 |
return(EINVAL); |
994 |
if (count == 8) { |
995 |
*tp++ = value; |
996 |
count = 0; |
997 |
} |
998 |
} |
999 |
break; |
1000 |
} |
1001 |
} |
1002 |
done: |
1003 |
if (cp >= end || tp >= eom) |
1004 |
return(EMSGSIZE); |
1005 |
|
1006 |
/* |
1007 |
* bit length validation: |
1008 |
* If a <length> is present, the number of digits in the <bit-data> |
1009 |
* MUST be just sufficient to contain the number of bits specified |
1010 |
* by the <length>. If there are insignificant bits in a final |
1011 |
* hexadecimal or octal digit, they MUST be zero. |
1012 |
* RFC 2673, Section 3.2. |
1013 |
*/ |
1014 |
if (blen > 0) { |
1015 |
int traillen; |
1016 |
|
1017 |
if (((blen + 3) & ~3) != tbcount) |
1018 |
return(EINVAL); |
1019 |
traillen = tbcount - blen; /* between 0 and 3 */ |
1020 |
if (((value << (8 - traillen)) & 0xff) != 0) |
1021 |
return(EINVAL); |
1022 |
} |
1023 |
else |
1024 |
blen = tbcount; |
1025 |
if (blen == 256) |
1026 |
blen = 0; |
1027 |
|
1028 |
/* encode the type and the significant bit fields */ |
1029 |
**labelp = DNS_LABELTYPE_BITSTRING; |
1030 |
**dst = blen; |
1031 |
|
1032 |
*bp = cp; |
1033 |
*dst = tp; |
1034 |
|
1035 |
return(0); |
1036 |
} /*2*/ |
1037 |
|
1038 |
/* |
1039 |
* dn_find(domain, msg, dnptrs, lastdnptr) |
1040 |
* Search for the counted-label name in an array of compressed names. |
1041 |
* return: |
1042 |
* offset from msg if found, or -1. |
1043 |
* notes: |
1044 |
* dnptrs is the pointer to the first name on the list, |
1045 |
* not the pointer to the start of the message. |
1046 |
*/ |
1047 |
static int |
1048 |
irc_dn_find(const unsigned char *domain, const unsigned char *msg, |
1049 |
const unsigned char * const *dnptrs, |
1050 |
const unsigned char * const *lastdnptr) |
1051 |
{ |
1052 |
const unsigned char *dn, *cp, *sp; |
1053 |
const unsigned char * const *cpp; |
1054 |
unsigned int n; |
1055 |
|
1056 |
for (cpp = dnptrs; cpp < lastdnptr; cpp++) |
1057 |
{ |
1058 |
sp = *cpp; |
1059 |
/* |
1060 |
* terminate search on: |
1061 |
* root label |
1062 |
* compression pointer |
1063 |
* unusable offset |
1064 |
*/ |
1065 |
while (*sp != 0 && (*sp & NS_CMPRSFLGS) == 0 && |
1066 |
(sp - msg) < 0x4000) { |
1067 |
dn = domain; |
1068 |
cp = sp; |
1069 |
while ((n = *cp++) != 0) { |
1070 |
/* |
1071 |
* check for indirection |
1072 |
*/ |
1073 |
switch (n & NS_CMPRSFLGS) { |
1074 |
case 0: /* normal case, n == len */ |
1075 |
n = labellen(cp - 1); /* XXX */ |
1076 |
|
1077 |
if (n != *dn++) |
1078 |
goto next; |
1079 |
|
1080 |
for ((void)NULL; n > 0; n--) |
1081 |
if (mklower(*dn++) != |
1082 |
mklower(*cp++)) |
1083 |
goto next; |
1084 |
/* Is next root for both ? */ |
1085 |
if (*dn == '\0' && *cp == '\0') |
1086 |
return (sp - msg); |
1087 |
if (*dn) |
1088 |
continue; |
1089 |
goto next; |
1090 |
case NS_CMPRSFLGS: /* indirection */ |
1091 |
cp = msg + (((n & 0x3f) << 8) | *cp); |
1092 |
break; |
1093 |
|
1094 |
default: /* illegal type */ |
1095 |
errno = EMSGSIZE; |
1096 |
return (-1); |
1097 |
} |
1098 |
} |
1099 |
next: ; |
1100 |
sp += *sp + 1; |
1101 |
} |
1102 |
} |
1103 |
errno = ENOENT; |
1104 |
return (-1); |
1105 |
} /*2*/ |
1106 |
|
1107 |
/* |
1108 |
* * Thinking in noninternationalized USASCII (per the DNS spec), |
1109 |
* * convert this character to lower case if it's upper case. |
1110 |
* */ |
1111 |
static int |
1112 |
mklower(int ch) |
1113 |
{ |
1114 |
if (ch >= 0x41 && ch <= 0x5A) |
1115 |
return(ch + 0x20); |
1116 |
|
1117 |
return(ch); |
1118 |
} /*2*/ |
1119 |
|
1120 |
/* From resolv/mkquery.c */ |
1121 |
|
1122 |
/* |
1123 |
* Form all types of queries. |
1124 |
* Returns the size of the result or -1. |
1125 |
*/ |
1126 |
int |
1127 |
irc_res_mkquery( |
1128 |
const char *dname, /* domain name */ |
1129 |
int class, int type, /* class and type of query */ |
1130 |
unsigned char *buf, /* buffer to put query */ |
1131 |
int buflen) /* size of buffer */ |
1132 |
{ |
1133 |
HEADER *hp; |
1134 |
unsigned char *cp; |
1135 |
int n; |
1136 |
unsigned char *dnptrs[20], **dpp, **lastdnptr; |
1137 |
|
1138 |
/* |
1139 |
* Initialize header fields. |
1140 |
*/ |
1141 |
if ((buf == NULL) || (buflen < HFIXEDSZ)) |
1142 |
return (-1); |
1143 |
memset(buf, 0, HFIXEDSZ); |
1144 |
hp = (HEADER *) buf; |
1145 |
|
1146 |
hp->id = 0; |
1147 |
hp->opcode = QUERY; |
1148 |
hp->rd = 1; /* recurse */ |
1149 |
hp->rcode = NO_ERRORS; |
1150 |
cp = buf + HFIXEDSZ; |
1151 |
buflen -= HFIXEDSZ; |
1152 |
dpp = dnptrs; |
1153 |
*dpp++ = buf; |
1154 |
*dpp++ = NULL; |
1155 |
lastdnptr = dnptrs + sizeof dnptrs / sizeof dnptrs[0]; |
1156 |
|
1157 |
if ((buflen -= QFIXEDSZ) < 0) |
1158 |
return (-1); |
1159 |
if ((n = irc_ns_name_compress(dname, cp, buflen, (const unsigned char **)dnptrs, |
1160 |
(const unsigned char **)lastdnptr)) < 0) |
1161 |
return (-1); |
1162 |
|
1163 |
cp += n; |
1164 |
buflen -= n; |
1165 |
IRC_NS_PUT16(type, cp); |
1166 |
IRC_NS_PUT16(class, cp); |
1167 |
hp->qdcount = htons(1); |
1168 |
|
1169 |
return (cp - buf); |
1170 |
} |