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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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* 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" |
80 |
#include "ircd_defs.h" |
81 |
#include "res.h" |
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#include "reslib.h" |
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#include "irc_string.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 |
88 |
|
89 |
/* $Id$ */ |
90 |
|
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struct irc_ssaddr irc_nsaddr_list[RESLIB_MAXNS]; |
92 |
unsigned int irc_nscount = 0; |
93 |
|
94 |
static const char digits[] = "0123456789"; |
95 |
static const char digitvalue[256] = { |
96 |
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*16*/ |
97 |
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*32*/ |
98 |
-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*/ |
100 |
-1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*80*/ |
101 |
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*96*/ |
102 |
-1, 10, 11, 12, 13, 14, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*112*/ |
103 |
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /*128*/ |
104 |
-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, |
108 |
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, |
109 |
-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*/ |
112 |
}; |
113 |
|
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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); |
120 |
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 *); |
124 |
static int irc_ns_name_uncompress(const unsigned char *, const unsigned char *, |
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const unsigned char *, char *, size_t); |
126 |
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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/* add_nameserver() |
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* |
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* input - either an IPV4 address in dotted quad |
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* or an IPV6 address in : format |
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* output - NONE |
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* side effects - entry in irc_nsaddr_list is filled in as needed |
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*/ |
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static void |
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add_nameserver(const char *arg) |
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{ |
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struct addrinfo hints, *res; |
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|
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/* Done max number of nameservers? */ |
146 |
if (irc_nscount >= RESLIB_MAXNS) |
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return; |
148 |
|
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memset(&hints, 0, sizeof(hints)); |
150 |
hints.ai_family = PF_UNSPEC; |
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hints.ai_socktype = SOCK_DGRAM; |
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hints.ai_flags = AI_PASSIVE | AI_NUMERICHOST; |
153 |
|
154 |
if (getaddrinfo(arg, "domain", &hints, &res)) |
155 |
return; |
156 |
|
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memcpy(&irc_nsaddr_list[irc_nscount].ss, res->ai_addr, res->ai_addrlen); |
158 |
irc_nsaddr_list[irc_nscount++].ss_len = res->ai_addrlen; |
159 |
freeaddrinfo(res); |
160 |
} |
161 |
|
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/* parse_resvconf() |
163 |
* |
164 |
* inputs - NONE |
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* output - -1 if failure 0 if success |
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* side effects - fills in irc_nsaddr_list |
167 |
*/ |
168 |
static void |
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parse_resvconf(void) |
170 |
{ |
171 |
char *p; |
172 |
char *opt; |
173 |
char *arg; |
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char input[MAXLINE]; |
175 |
FILE *file; |
176 |
|
177 |
/* XXX "/etc/resolv.conf" should be from a define in config.h perhaps |
178 |
* for cygwin support etc. this hardcodes it to unix for now -db |
179 |
*/ |
180 |
if ((file = fopen("/etc/resolv.conf", "r")) == NULL) |
181 |
return; |
182 |
|
183 |
while (fgets(input, sizeof(input), file)) |
184 |
{ |
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/* blow away any newline */ |
186 |
if ((p = strpbrk(input, "\r\n"))) |
187 |
*p = '\0'; |
188 |
|
189 |
p = input; |
190 |
|
191 |
/* skip until something thats not a space is seen */ |
192 |
while (IsSpace(*p)) |
193 |
++p; |
194 |
|
195 |
/* if at this point, have a '\0' then continue */ |
196 |
if (*p == '\0') |
197 |
continue; |
198 |
|
199 |
/* Ignore comment lines immediately */ |
200 |
if (*p == ';' || *p == '#') |
201 |
continue; |
202 |
|
203 |
/* skip until a space is found */ |
204 |
opt = p; |
205 |
while (!IsSpace(*p) && *p) |
206 |
++p; |
207 |
|
208 |
if (*p == '\0') |
209 |
continue; /* no arguments?.. ignore this line */ |
210 |
|
211 |
/* blow away the space character */ |
212 |
*p++ = '\0'; |
213 |
|
214 |
/* skip these spaces that are before the argument */ |
215 |
while (IsSpace(*p)) |
216 |
++p; |
217 |
|
218 |
/* Now arg should be right where p is pointing */ |
219 |
arg = p; |
220 |
|
221 |
if ((p = strpbrk(arg, " \t"))) |
222 |
*p = '\0'; /* take the first word */ |
223 |
|
224 |
if (!strcasecmp(opt, "nameserver")) |
225 |
add_nameserver(arg); |
226 |
} |
227 |
|
228 |
fclose(file); |
229 |
} |
230 |
|
231 |
void |
232 |
irc_res_init(void) |
233 |
{ |
234 |
irc_nscount = 0; |
235 |
memset(irc_nsaddr_list, 0, sizeof(irc_nsaddr_list)); |
236 |
|
237 |
parse_resvconf(); |
238 |
|
239 |
if (!irc_nscount) |
240 |
add_nameserver("127.0.0.1"); |
241 |
} |
242 |
|
243 |
/* |
244 |
* Expand compressed domain name 'comp_dn' to full domain name. |
245 |
* 'msg' is a pointer to the begining of the message, |
246 |
* 'eomorig' points to the first location after the message, |
247 |
* 'exp_dn' is a pointer to a buffer of size 'length' for the result. |
248 |
* Return size of compressed name or -1 if there was an error. |
249 |
*/ |
250 |
int |
251 |
irc_dn_expand(const unsigned char *msg, const unsigned char *eom, |
252 |
const unsigned char *src, char *dst, int dstsiz) |
253 |
{ |
254 |
int n = irc_ns_name_uncompress(msg, eom, src, dst, (size_t)dstsiz); |
255 |
|
256 |
if (n > 0 && dst[0] == '.') |
257 |
dst[0] = '\0'; |
258 |
return n; |
259 |
} |
260 |
|
261 |
/* |
262 |
* irc_ns_name_uncompress(msg, eom, src, dst, dstsiz) |
263 |
* Expand compressed domain name to presentation format. |
264 |
* return: |
265 |
* Number of bytes read out of `src', or -1 (with errno set). |
266 |
* note: |
267 |
* Root domain returns as "." not "". |
268 |
*/ |
269 |
static int |
270 |
irc_ns_name_uncompress(const unsigned char *msg, const unsigned char *eom, |
271 |
const unsigned char *src, char *dst, size_t dstsiz) |
272 |
{ |
273 |
unsigned char tmp[NS_MAXCDNAME]; |
274 |
int n; |
275 |
|
276 |
if ((n = irc_ns_name_unpack(msg, eom, src, tmp, sizeof tmp)) == -1) |
277 |
return -1; |
278 |
if (irc_ns_name_ntop(tmp, dst, dstsiz) == -1) |
279 |
return -1; |
280 |
return n; |
281 |
} |
282 |
|
283 |
/* |
284 |
* irc_ns_name_unpack(msg, eom, src, dst, dstsiz) |
285 |
* Unpack a domain name from a message, source may be compressed. |
286 |
* return: |
287 |
* -1 if it fails, or consumed octets if it succeeds. |
288 |
*/ |
289 |
static int |
290 |
irc_ns_name_unpack(const unsigned char *msg, const unsigned char *eom, |
291 |
const unsigned char *src, unsigned char *dst, |
292 |
size_t dstsiz) |
293 |
{ |
294 |
const unsigned char *srcp, *dstlim; |
295 |
unsigned char *dstp; |
296 |
int n, len, checked, l; |
297 |
|
298 |
len = -1; |
299 |
checked = 0; |
300 |
dstp = dst; |
301 |
srcp = src; |
302 |
dstlim = dst + dstsiz; |
303 |
|
304 |
if (srcp < msg || srcp >= eom) |
305 |
{ |
306 |
errno = EMSGSIZE; |
307 |
return -1; |
308 |
} |
309 |
|
310 |
/* Fetch next label in domain name. */ |
311 |
while ((n = *srcp++) != 0) |
312 |
{ |
313 |
/* Check for indirection. */ |
314 |
switch (n & NS_CMPRSFLGS) |
315 |
{ |
316 |
case 0: |
317 |
case NS_TYPE_ELT: |
318 |
/* Limit checks. */ |
319 |
if ((l = labellen(srcp - 1)) < 0) |
320 |
{ |
321 |
errno = EMSGSIZE; |
322 |
return -1; |
323 |
} |
324 |
|
325 |
if (dstp + l + 1 >= dstlim || srcp + l >= eom) |
326 |
{ |
327 |
errno = EMSGSIZE; |
328 |
return -1; |
329 |
} |
330 |
|
331 |
checked += l + 1; |
332 |
*dstp++ = n; |
333 |
memcpy(dstp, srcp, l); |
334 |
|
335 |
dstp += l; |
336 |
srcp += l; |
337 |
break; |
338 |
|
339 |
case NS_CMPRSFLGS: |
340 |
if (srcp >= eom) |
341 |
{ |
342 |
errno = EMSGSIZE; |
343 |
return -1; |
344 |
} |
345 |
|
346 |
if (len < 0) |
347 |
len = srcp - src + 1; |
348 |
srcp = msg + (((n & 0x3f) << 8) | (*srcp & 0xff)); |
349 |
|
350 |
if (srcp < msg || srcp >= eom) |
351 |
{ |
352 |
/* Out of range. */ |
353 |
errno = EMSGSIZE; |
354 |
return -1; |
355 |
} |
356 |
|
357 |
checked += 2; |
358 |
|
359 |
/* |
360 |
* Check for loops in the compressed name; |
361 |
* if we've looked at the whole message, |
362 |
* there must be a loop. |
363 |
*/ |
364 |
if (checked >= eom - msg) |
365 |
{ |
366 |
errno = EMSGSIZE; |
367 |
return -1; |
368 |
} |
369 |
|
370 |
break; |
371 |
|
372 |
default: |
373 |
errno = EMSGSIZE; |
374 |
return -1; /* Flag error */ |
375 |
} |
376 |
} |
377 |
|
378 |
*dstp = '\0'; |
379 |
|
380 |
if (len < 0) |
381 |
len = srcp - src; |
382 |
|
383 |
return len; |
384 |
} |
385 |
|
386 |
/* |
387 |
* irc_ns_name_ntop(src, dst, dstsiz) |
388 |
* Convert an encoded domain name to printable ascii as per RFC1035. |
389 |
* return: |
390 |
* Number of bytes written to buffer, or -1 (with errno set) |
391 |
* notes: |
392 |
* The root is returned as "." |
393 |
* All other domains are returned in non absolute form |
394 |
*/ |
395 |
static int |
396 |
irc_ns_name_ntop(const unsigned char *src, char *dst, size_t dstsiz) |
397 |
{ |
398 |
const unsigned char *cp; |
399 |
char *dn, *eom; |
400 |
unsigned char c; |
401 |
unsigned int n; |
402 |
int l; |
403 |
|
404 |
cp = src; |
405 |
dn = dst; |
406 |
eom = dst + dstsiz; |
407 |
|
408 |
while ((n = *cp++) != 0) { |
409 |
if ((n & NS_CMPRSFLGS) == NS_CMPRSFLGS) { |
410 |
/* Some kind of compression pointer. */ |
411 |
errno = EMSGSIZE; |
412 |
return (-1); |
413 |
} |
414 |
if (dn != dst) { |
415 |
if (dn >= eom) { |
416 |
errno = EMSGSIZE; |
417 |
return (-1); |
418 |
} |
419 |
*dn++ = '.'; |
420 |
} |
421 |
if ((l = labellen((cp - 1))) < 0) { |
422 |
errno = EMSGSIZE; /* XXX */ |
423 |
return(-1); |
424 |
} |
425 |
if (dn + l >= eom) { |
426 |
errno = EMSGSIZE; |
427 |
return (-1); |
428 |
} |
429 |
if ((n & NS_CMPRSFLGS) == NS_TYPE_ELT) { |
430 |
int m; |
431 |
|
432 |
if (n != DNS_LABELTYPE_BITSTRING) { |
433 |
/* XXX: labellen should reject this case */ |
434 |
errno = EINVAL; |
435 |
return(-1); |
436 |
} |
437 |
if ((m = irc_decode_bitstring(&cp, dn, eom)) < 0) |
438 |
{ |
439 |
errno = EMSGSIZE; |
440 |
return(-1); |
441 |
} |
442 |
dn += m; |
443 |
continue; |
444 |
} |
445 |
for ((void)NULL; l > 0; l--) { |
446 |
c = *cp++; |
447 |
if (special(c)) { |
448 |
if (dn + 1 >= eom) { |
449 |
errno = EMSGSIZE; |
450 |
return (-1); |
451 |
} |
452 |
*dn++ = '\\'; |
453 |
*dn++ = (char)c; |
454 |
} else if (!printable(c)) { |
455 |
if (dn + 3 >= eom) { |
456 |
errno = EMSGSIZE; |
457 |
return (-1); |
458 |
} |
459 |
*dn++ = '\\'; |
460 |
*dn++ = digits[c / 100]; |
461 |
*dn++ = digits[(c % 100) / 10]; |
462 |
*dn++ = digits[c % 10]; |
463 |
} else { |
464 |
if (dn >= eom) { |
465 |
errno = EMSGSIZE; |
466 |
return (-1); |
467 |
} |
468 |
*dn++ = (char)c; |
469 |
} |
470 |
} |
471 |
} |
472 |
if (dn == dst) { |
473 |
if (dn >= eom) { |
474 |
errno = EMSGSIZE; |
475 |
return (-1); |
476 |
} |
477 |
*dn++ = '.'; |
478 |
} |
479 |
if (dn >= eom) { |
480 |
errno = EMSGSIZE; |
481 |
return (-1); |
482 |
} |
483 |
*dn++ = '\0'; |
484 |
return (dn - dst); |
485 |
} /*2*/ |
486 |
|
487 |
/* |
488 |
* Skip over a compressed domain name. Return the size or -1. |
489 |
*/ |
490 |
int |
491 |
irc_dn_skipname(const unsigned char *ptr, const unsigned char *eom) |
492 |
{ |
493 |
const unsigned char *saveptr = ptr; |
494 |
|
495 |
if (irc_ns_name_skip(&ptr, eom) == -1) |
496 |
return -1; |
497 |
return ptr - saveptr; |
498 |
} |
499 |
|
500 |
/* |
501 |
* ns_name_skip(ptrptr, eom) |
502 |
* Advance *ptrptr to skip over the compressed name it points at. |
503 |
* return: |
504 |
* 0 on success, -1 (with errno set) on failure. |
505 |
*/ |
506 |
static int |
507 |
irc_ns_name_skip(const unsigned char **ptrptr, const unsigned char *eom) |
508 |
{ |
509 |
const unsigned char *cp; |
510 |
unsigned int n; |
511 |
int l; |
512 |
|
513 |
cp = *ptrptr; |
514 |
|
515 |
while (cp < eom && (n = *cp++) != 0) |
516 |
{ |
517 |
/* Check for indirection. */ |
518 |
switch (n & NS_CMPRSFLGS) |
519 |
{ |
520 |
case 0: /* Normal case, n == len */ |
521 |
cp += n; |
522 |
continue; |
523 |
case NS_TYPE_ELT: /* EDNS0 extended label */ |
524 |
if ((l = labellen(cp - 1)) < 0) |
525 |
{ |
526 |
errno = EMSGSIZE; /* XXX */ |
527 |
return -1; |
528 |
} |
529 |
|
530 |
cp += l; |
531 |
continue; |
532 |
case NS_CMPRSFLGS: /* Indirection */ |
533 |
cp++; |
534 |
break; |
535 |
default: /* Illegal type */ |
536 |
errno = EMSGSIZE; |
537 |
return -1; |
538 |
} |
539 |
|
540 |
break; |
541 |
} |
542 |
|
543 |
if (cp > eom) |
544 |
{ |
545 |
errno = EMSGSIZE; |
546 |
return -1; |
547 |
} |
548 |
|
549 |
*ptrptr = cp; |
550 |
return 0; |
551 |
} |
552 |
|
553 |
unsigned int |
554 |
irc_ns_get16(const unsigned char *src) |
555 |
{ |
556 |
unsigned int dst; |
557 |
|
558 |
IRC_NS_GET16(dst, src); |
559 |
return dst; |
560 |
} |
561 |
|
562 |
unsigned long |
563 |
irc_ns_get32(const unsigned char *src) |
564 |
{ |
565 |
unsigned long dst; |
566 |
|
567 |
IRC_NS_GET32(dst, src); |
568 |
return dst; |
569 |
} |
570 |
|
571 |
void |
572 |
irc_ns_put16(unsigned int src, unsigned char *dst) |
573 |
{ |
574 |
IRC_NS_PUT16(src, dst); |
575 |
} |
576 |
|
577 |
void |
578 |
irc_ns_put32(unsigned long src, unsigned char *dst) |
579 |
{ |
580 |
IRC_NS_PUT32(src, dst); |
581 |
} |
582 |
|
583 |
/* From ns_name.c */ |
584 |
|
585 |
/* |
586 |
* special(ch) |
587 |
* Thinking in noninternationalized USASCII (per the DNS spec), |
588 |
* is this characted special ("in need of quoting") ? |
589 |
* return: |
590 |
* boolean. |
591 |
*/ |
592 |
static int |
593 |
special(int ch) |
594 |
{ |
595 |
switch (ch) |
596 |
{ |
597 |
case 0x22: /* '"' */ |
598 |
case 0x2E: /* '.' */ |
599 |
case 0x3B: /* ';' */ |
600 |
case 0x5C: /* '\\' */ |
601 |
case 0x28: /* '(' */ |
602 |
case 0x29: /* ')' */ |
603 |
/* Special modifiers in zone files. */ |
604 |
case 0x40: /* '@' */ |
605 |
case 0x24: /* '$' */ |
606 |
return 1; |
607 |
default: |
608 |
return 0; |
609 |
} |
610 |
} |
611 |
|
612 |
static int |
613 |
labellen(const unsigned char *lp) |
614 |
{ |
615 |
int bitlen; |
616 |
unsigned char l = *lp; |
617 |
|
618 |
if ((l & NS_CMPRSFLGS) == NS_CMPRSFLGS) |
619 |
{ |
620 |
/* Should be avoided by the caller */ |
621 |
return -1; |
622 |
} |
623 |
|
624 |
if ((l & NS_CMPRSFLGS) == NS_TYPE_ELT) |
625 |
{ |
626 |
if (l == DNS_LABELTYPE_BITSTRING) |
627 |
{ |
628 |
if ((bitlen = *(lp + 1)) == 0) |
629 |
bitlen = 256; |
630 |
return (bitlen + 7 ) / 8 + 1; |
631 |
} |
632 |
|
633 |
return -1; /* Unknwon ELT */ |
634 |
} |
635 |
|
636 |
return l; |
637 |
} |
638 |
|
639 |
|
640 |
/* |
641 |
* printable(ch) |
642 |
* Thinking in noninternationalized USASCII (per the DNS spec), |
643 |
* is this character visible and not a space when printed ? |
644 |
* return: |
645 |
* boolean. |
646 |
*/ |
647 |
static int |
648 |
printable(int ch) |
649 |
{ |
650 |
return ch > 0x20 && ch < 0x7f; |
651 |
} |
652 |
|
653 |
static int |
654 |
irc_decode_bitstring(const unsigned char **cpp, char *dn, const char *eom) |
655 |
{ |
656 |
const unsigned char *cp = *cpp; |
657 |
char *beg = dn, tc; |
658 |
int b, blen, plen; |
659 |
|
660 |
if ((blen = (*cp & 0xff)) == 0) |
661 |
blen = 256; |
662 |
plen = (blen + 3) / 4; |
663 |
plen += sizeof("\\[x/]") + (blen > 99 ? 3 : (blen > 9) ? 2 : 1); |
664 |
if (dn + plen >= eom) |
665 |
return(-1); |
666 |
|
667 |
cp++; |
668 |
dn += sprintf(dn, "\\[x"); |
669 |
for (b = blen; b > 7; b -= 8, cp++) |
670 |
dn += sprintf(dn, "%02x", *cp & 0xff); |
671 |
if (b > 4) { |
672 |
tc = *cp++; |
673 |
dn += sprintf(dn, "%02x", tc & (0xff << (8 - b))); |
674 |
} else if (b > 0) { |
675 |
tc = *cp++; |
676 |
dn += sprintf(dn, "%1x", |
677 |
((tc >> 4) & 0x0f) & (0x0f << (4 - b))); |
678 |
} |
679 |
dn += sprintf(dn, "/%d]", blen); |
680 |
|
681 |
*cpp = cp; |
682 |
return(dn - beg); |
683 |
} /*2*/ |
684 |
|
685 |
/* |
686 |
* irc_ns_name_pton(src, dst, dstsiz) |
687 |
* Convert a ascii string into an encoded domain name as per RFC1035. |
688 |
* return: |
689 |
* -1 if it fails |
690 |
* 1 if string was fully qualified |
691 |
* 0 is string was not fully qualified |
692 |
* notes: |
693 |
* Enforces label and domain length limits. |
694 |
*/ |
695 |
static int |
696 |
irc_ns_name_pton(const char *src, unsigned char *dst, size_t dstsiz) |
697 |
{ |
698 |
unsigned char *label, *bp, *eom; |
699 |
char *cp; |
700 |
int c, n, escaped, e = 0; |
701 |
|
702 |
escaped = 0; |
703 |
bp = dst; |
704 |
eom = dst + dstsiz; |
705 |
label = bp++; |
706 |
|
707 |
|
708 |
while ((c = *src++) != 0) { |
709 |
if (escaped) { |
710 |
if (c == '[') { /* start a bit string label */ |
711 |
if ((cp = strchr(src, ']')) == NULL) { |
712 |
errno = EINVAL; /* ??? */ |
713 |
return(-1); |
714 |
} |
715 |
if ((e = irc_encode_bitsring(&src, |
716 |
cp + 2, |
717 |
&label, |
718 |
&bp, |
719 |
eom)) |
720 |
!= 0) { |
721 |
errno = e; |
722 |
return(-1); |
723 |
} |
724 |
escaped = 0; |
725 |
label = bp++; |
726 |
if ((c = *src++) == 0) |
727 |
goto done; |
728 |
else if (c != '.') { |
729 |
errno = EINVAL; |
730 |
return(-1); |
731 |
} |
732 |
continue; |
733 |
} |
734 |
else if ((cp = strchr(digits, c)) != NULL) { |
735 |
n = (cp - digits) * 100; |
736 |
if ((c = *src++) == 0 || |
737 |
(cp = strchr(digits, c)) == NULL) { |
738 |
errno = EMSGSIZE; |
739 |
return (-1); |
740 |
} |
741 |
n += (cp - digits) * 10; |
742 |
if ((c = *src++) == 0 || |
743 |
(cp = strchr(digits, c)) == NULL) { |
744 |
errno = EMSGSIZE; |
745 |
return (-1); |
746 |
} |
747 |
n += (cp - digits); |
748 |
if (n > 255) { |
749 |
errno = EMSGSIZE; |
750 |
return (-1); |
751 |
} |
752 |
c = n; |
753 |
} |
754 |
escaped = 0; |
755 |
} else if (c == '\\') { |
756 |
escaped = 1; |
757 |
continue; |
758 |
} else if (c == '.') { |
759 |
c = (bp - label - 1); |
760 |
if ((c & NS_CMPRSFLGS) != 0) { /* Label too big. */ |
761 |
errno = EMSGSIZE; |
762 |
return (-1); |
763 |
} |
764 |
if (label >= eom) { |
765 |
errno = EMSGSIZE; |
766 |
return (-1); |
767 |
} |
768 |
*label = c; |
769 |
/* Fully qualified ? */ |
770 |
if (*src == '\0') { |
771 |
if (c != 0) { |
772 |
if (bp >= eom) { |
773 |
errno = EMSGSIZE; |
774 |
return (-1); |
775 |
} |
776 |
*bp++ = '\0'; |
777 |
} |
778 |
if ((bp - dst) > NS_MAXCDNAME) { |
779 |
errno = EMSGSIZE; |
780 |
return (-1); |
781 |
} |
782 |
return (1); |
783 |
} |
784 |
if (c == 0 || *src == '.') { |
785 |
errno = EMSGSIZE; |
786 |
return (-1); |
787 |
} |
788 |
label = bp++; |
789 |
continue; |
790 |
} |
791 |
if (bp >= eom) { |
792 |
errno = EMSGSIZE; |
793 |
return (-1); |
794 |
} |
795 |
*bp++ = (unsigned char)c; |
796 |
} |
797 |
c = (bp - label - 1); |
798 |
if ((c & NS_CMPRSFLGS) != 0) { /* Label too big. */ |
799 |
errno = EMSGSIZE; |
800 |
return (-1); |
801 |
} |
802 |
done: |
803 |
if (label >= eom) { |
804 |
errno = EMSGSIZE; |
805 |
return (-1); |
806 |
} |
807 |
*label = c; |
808 |
if (c != 0) { |
809 |
if (bp >= eom) { |
810 |
errno = EMSGSIZE; |
811 |
return (-1); |
812 |
} |
813 |
*bp++ = 0; |
814 |
} |
815 |
|
816 |
if ((bp - dst) > NS_MAXCDNAME) |
817 |
{ /* src too big */ |
818 |
errno = EMSGSIZE; |
819 |
return (-1); |
820 |
} |
821 |
|
822 |
return (0); |
823 |
} /*2*/ |
824 |
|
825 |
/* |
826 |
* irc_ns_name_pack(src, dst, dstsiz, dnptrs, lastdnptr) |
827 |
* Pack domain name 'domain' into 'comp_dn'. |
828 |
* return: |
829 |
* Size of the compressed name, or -1. |
830 |
* notes: |
831 |
* 'dnptrs' is an array of pointers to previous compressed names. |
832 |
* dnptrs[0] is a pointer to the beginning of the message. The array |
833 |
* ends with NULL. |
834 |
* 'lastdnptr' is a pointer to the end of the array pointed to |
835 |
* by 'dnptrs'. |
836 |
* Side effects: |
837 |
* The list of pointers in dnptrs is updated for labels inserted into |
838 |
* the message as we compress the name. If 'dnptr' is NULL, we don't |
839 |
* try to compress names. If 'lastdnptr' is NULL, we don't update the |
840 |
* list. |
841 |
*/ |
842 |
static int |
843 |
irc_ns_name_pack(const unsigned char *src, unsigned char *dst, int dstsiz, |
844 |
const unsigned char **dnptrs, const unsigned char **lastdnptr) |
845 |
{ |
846 |
unsigned char *dstp; |
847 |
const unsigned char **cpp, **lpp, *eob, *msg; |
848 |
const unsigned char *srcp; |
849 |
int n, l, first = 1; |
850 |
|
851 |
srcp = src; |
852 |
dstp = dst; |
853 |
eob = dstp + dstsiz; |
854 |
lpp = cpp = NULL; |
855 |
|
856 |
if (dnptrs != NULL) |
857 |
{ |
858 |
if ((msg = *dnptrs++)) |
859 |
{ |
860 |
for (cpp = dnptrs; *cpp != NULL; cpp++) |
861 |
; |
862 |
lpp = cpp; /* End of list to search */ |
863 |
} |
864 |
} |
865 |
else |
866 |
msg = NULL; |
867 |
|
868 |
/* Make sure the domain we are about to add is legal */ |
869 |
l = 0; |
870 |
do |
871 |
{ |
872 |
int l0; |
873 |
|
874 |
n = *srcp; |
875 |
if ((n & NS_CMPRSFLGS) == NS_CMPRSFLGS) |
876 |
{ |
877 |
errno = EMSGSIZE; |
878 |
return -1; |
879 |
} |
880 |
|
881 |
if ((l0 = labellen(srcp)) < 0) |
882 |
{ |
883 |
errno = EINVAL; |
884 |
return -1; |
885 |
} |
886 |
|
887 |
l += l0 + 1; |
888 |
if (l > NS_MAXCDNAME) |
889 |
{ |
890 |
errno = EMSGSIZE; |
891 |
return -1; |
892 |
} |
893 |
|
894 |
srcp += l0 + 1; |
895 |
} while (n != 0); |
896 |
|
897 |
/* From here on we need to reset compression pointer array on error */ |
898 |
srcp = src; |
899 |
do |
900 |
{ |
901 |
/* Look to see if we can use pointers. */ |
902 |
n = *srcp; |
903 |
|
904 |
if (n != 0 && msg != NULL) |
905 |
{ |
906 |
l = irc_dn_find(srcp, msg, (const unsigned char *const *)dnptrs, |
907 |
(const unsigned char *const *)lpp); |
908 |
|
909 |
if (l >= 0) |
910 |
{ |
911 |
if (dstp + 1 >= eob) |
912 |
goto cleanup; |
913 |
|
914 |
*dstp++ = (l >> 8) | NS_CMPRSFLGS; |
915 |
*dstp++ = l % 256; |
916 |
return dstp - dst; |
917 |
} |
918 |
|
919 |
/* Not found, save it. */ |
920 |
if (lastdnptr != NULL && cpp < lastdnptr - 1 && (dstp - msg) < 0x4000 && first) |
921 |
{ |
922 |
*cpp++ = dstp; |
923 |
*cpp = NULL; |
924 |
first = 0; |
925 |
} |
926 |
} |
927 |
|
928 |
/* Copy label to buffer */ |
929 |
if ((n & NS_CMPRSFLGS) == NS_CMPRSFLGS) |
930 |
goto cleanup; /* Should not happen. */ |
931 |
|
932 |
n = labellen(srcp); |
933 |
if (dstp + 1 + n >= eob) |
934 |
goto cleanup; |
935 |
|
936 |
memcpy(dstp, srcp, n + 1); |
937 |
srcp += n + 1; |
938 |
dstp += n + 1; |
939 |
} while (n != 0); |
940 |
|
941 |
if (dstp > eob) |
942 |
{ |
943 |
cleanup: |
944 |
if (msg != NULL) |
945 |
*lpp = NULL; |
946 |
errno = EMSGSIZE; |
947 |
return -1; |
948 |
} |
949 |
|
950 |
return dstp - dst; |
951 |
} |
952 |
|
953 |
static int |
954 |
irc_ns_name_compress(const char *src, unsigned char *dst, size_t dstsiz, |
955 |
const unsigned char **dnptrs, const unsigned char **lastdnptr) |
956 |
{ |
957 |
unsigned char tmp[NS_MAXCDNAME]; |
958 |
|
959 |
if (irc_ns_name_pton(src, tmp, sizeof tmp) == -1) |
960 |
return -1; |
961 |
return irc_ns_name_pack(tmp, dst, dstsiz, dnptrs, lastdnptr); |
962 |
} |
963 |
|
964 |
static int |
965 |
irc_encode_bitsring(const char **bp, const char *end, unsigned char **labelp, |
966 |
unsigned char **dst, const unsigned char *eom) |
967 |
{ |
968 |
int afterslash = 0; |
969 |
const char *cp = *bp; |
970 |
unsigned char *tp; |
971 |
char c; |
972 |
const char *beg_blen; |
973 |
char *end_blen = NULL; |
974 |
int value = 0, count = 0, tbcount = 0, blen = 0; |
975 |
|
976 |
beg_blen = end_blen = NULL; |
977 |
|
978 |
/* a bitstring must contain at least 2 characters */ |
979 |
if (end - cp < 2) |
980 |
return(EINVAL); |
981 |
|
982 |
/* XXX: currently, only hex strings are supported */ |
983 |
if (*cp++ != 'x') |
984 |
return(EINVAL); |
985 |
if (!isxdigit((*cp) & 0xff)) /* reject '\[x/BLEN]' */ |
986 |
return(EINVAL); |
987 |
|
988 |
for (tp = *dst + 1; cp < end && tp < eom; cp++) { |
989 |
switch((c = *cp)) { |
990 |
case ']': /* end of the bitstring */ |
991 |
if (afterslash) { |
992 |
if (beg_blen == NULL) |
993 |
return(EINVAL); |
994 |
blen = (int)strtol(beg_blen, &end_blen, 10); |
995 |
if (*end_blen != ']') |
996 |
return(EINVAL); |
997 |
} |
998 |
if (count) |
999 |
*tp++ = ((value << 4) & 0xff); |
1000 |
cp++; /* skip ']' */ |
1001 |
goto done; |
1002 |
case '/': |
1003 |
afterslash = 1; |
1004 |
break; |
1005 |
default: |
1006 |
if (afterslash) { |
1007 |
if (!isdigit(c&0xff)) |
1008 |
return(EINVAL); |
1009 |
if (beg_blen == NULL) { |
1010 |
|
1011 |
if (c == '0') { |
1012 |
/* blen never begings with 0 */ |
1013 |
return(EINVAL); |
1014 |
} |
1015 |
beg_blen = cp; |
1016 |
} |
1017 |
} else { |
1018 |
if (!isxdigit(c&0xff)) |
1019 |
return(EINVAL); |
1020 |
value <<= 4; |
1021 |
value += digitvalue[(int)c]; |
1022 |
count += 4; |
1023 |
tbcount += 4; |
1024 |
if (tbcount > 256) |
1025 |
return(EINVAL); |
1026 |
if (count == 8) { |
1027 |
*tp++ = value; |
1028 |
count = 0; |
1029 |
} |
1030 |
} |
1031 |
break; |
1032 |
} |
1033 |
} |
1034 |
done: |
1035 |
if (cp >= end || tp >= eom) |
1036 |
return(EMSGSIZE); |
1037 |
|
1038 |
/* |
1039 |
* bit length validation: |
1040 |
* If a <length> is present, the number of digits in the <bit-data> |
1041 |
* MUST be just sufficient to contain the number of bits specified |
1042 |
* by the <length>. If there are insignificant bits in a final |
1043 |
* hexadecimal or octal digit, they MUST be zero. |
1044 |
* RFC 2673, Section 3.2. |
1045 |
*/ |
1046 |
if (blen > 0) { |
1047 |
int traillen; |
1048 |
|
1049 |
if (((blen + 3) & ~3) != tbcount) |
1050 |
return(EINVAL); |
1051 |
traillen = tbcount - blen; /* between 0 and 3 */ |
1052 |
if (((value << (8 - traillen)) & 0xff) != 0) |
1053 |
return(EINVAL); |
1054 |
} |
1055 |
else |
1056 |
blen = tbcount; |
1057 |
if (blen == 256) |
1058 |
blen = 0; |
1059 |
|
1060 |
/* encode the type and the significant bit fields */ |
1061 |
**labelp = DNS_LABELTYPE_BITSTRING; |
1062 |
**dst = blen; |
1063 |
|
1064 |
*bp = cp; |
1065 |
*dst = tp; |
1066 |
|
1067 |
return(0); |
1068 |
} /*2*/ |
1069 |
|
1070 |
/* |
1071 |
* dn_find(domain, msg, dnptrs, lastdnptr) |
1072 |
* Search for the counted-label name in an array of compressed names. |
1073 |
* return: |
1074 |
* offset from msg if found, or -1. |
1075 |
* notes: |
1076 |
* dnptrs is the pointer to the first name on the list, |
1077 |
* not the pointer to the start of the message. |
1078 |
*/ |
1079 |
static int |
1080 |
irc_dn_find(const unsigned char *domain, const unsigned char *msg, |
1081 |
const unsigned char * const *dnptrs, |
1082 |
const unsigned char * const *lastdnptr) |
1083 |
{ |
1084 |
const unsigned char *dn, *cp, *sp; |
1085 |
const unsigned char * const *cpp; |
1086 |
unsigned int n; |
1087 |
|
1088 |
for (cpp = dnptrs; cpp < lastdnptr; cpp++) |
1089 |
{ |
1090 |
sp = *cpp; |
1091 |
/* |
1092 |
* terminate search on: |
1093 |
* root label |
1094 |
* compression pointer |
1095 |
* unusable offset |
1096 |
*/ |
1097 |
while (*sp != 0 && (*sp & NS_CMPRSFLGS) == 0 && |
1098 |
(sp - msg) < 0x4000) { |
1099 |
dn = domain; |
1100 |
cp = sp; |
1101 |
while ((n = *cp++) != 0) { |
1102 |
/* |
1103 |
* check for indirection |
1104 |
*/ |
1105 |
switch (n & NS_CMPRSFLGS) { |
1106 |
case 0: /* normal case, n == len */ |
1107 |
n = labellen(cp - 1); /* XXX */ |
1108 |
|
1109 |
if (n != *dn++) |
1110 |
goto next; |
1111 |
|
1112 |
for ((void)NULL; n > 0; n--) |
1113 |
if (mklower(*dn++) != |
1114 |
mklower(*cp++)) |
1115 |
goto next; |
1116 |
/* Is next root for both ? */ |
1117 |
if (*dn == '\0' && *cp == '\0') |
1118 |
return (sp - msg); |
1119 |
if (*dn) |
1120 |
continue; |
1121 |
goto next; |
1122 |
case NS_CMPRSFLGS: /* indirection */ |
1123 |
cp = msg + (((n & 0x3f) << 8) | *cp); |
1124 |
break; |
1125 |
|
1126 |
default: /* illegal type */ |
1127 |
errno = EMSGSIZE; |
1128 |
return (-1); |
1129 |
} |
1130 |
} |
1131 |
next: ; |
1132 |
sp += *sp + 1; |
1133 |
} |
1134 |
} |
1135 |
errno = ENOENT; |
1136 |
return (-1); |
1137 |
} /*2*/ |
1138 |
|
1139 |
/* |
1140 |
* * Thinking in noninternationalized USASCII (per the DNS spec), |
1141 |
* * convert this character to lower case if it's upper case. |
1142 |
* */ |
1143 |
static int |
1144 |
mklower(int ch) |
1145 |
{ |
1146 |
if (ch >= 0x41 && ch <= 0x5A) |
1147 |
return(ch + 0x20); |
1148 |
|
1149 |
return(ch); |
1150 |
} /*2*/ |
1151 |
|
1152 |
/* From resolv/mkquery.c */ |
1153 |
|
1154 |
/* |
1155 |
* Form all types of queries. |
1156 |
* Returns the size of the result or -1. |
1157 |
*/ |
1158 |
int |
1159 |
irc_res_mkquery( |
1160 |
const char *dname, /* domain name */ |
1161 |
int class, int type, /* class and type of query */ |
1162 |
unsigned char *buf, /* buffer to put query */ |
1163 |
int buflen) /* size of buffer */ |
1164 |
{ |
1165 |
HEADER *hp; |
1166 |
unsigned char *cp; |
1167 |
int n; |
1168 |
const unsigned char *dnptrs[20], **dpp, **lastdnptr; |
1169 |
|
1170 |
/* |
1171 |
* Initialize header fields. |
1172 |
*/ |
1173 |
if ((buf == NULL) || (buflen < HFIXEDSZ)) |
1174 |
return (-1); |
1175 |
memset(buf, 0, HFIXEDSZ); |
1176 |
hp = (HEADER *) buf; |
1177 |
|
1178 |
hp->id = 0; |
1179 |
hp->opcode = QUERY; |
1180 |
hp->rd = 1; /* recurse */ |
1181 |
hp->rcode = NO_ERRORS; |
1182 |
cp = buf + HFIXEDSZ; |
1183 |
buflen -= HFIXEDSZ; |
1184 |
dpp = dnptrs; |
1185 |
*dpp++ = buf; |
1186 |
*dpp++ = NULL; |
1187 |
lastdnptr = dnptrs + sizeof dnptrs / sizeof dnptrs[0]; |
1188 |
|
1189 |
if ((buflen -= QFIXEDSZ) < 0) |
1190 |
return (-1); |
1191 |
if ((n = irc_ns_name_compress(dname, cp, buflen, dnptrs, |
1192 |
lastdnptr)) < 0) |
1193 |
return (-1); |
1194 |
|
1195 |
cp += n; |
1196 |
buflen -= n; |
1197 |
IRC_NS_PUT16(type, cp); |
1198 |
IRC_NS_PUT16(class, cp); |
1199 |
hp->qdcount = htons(1); |
1200 |
|
1201 |
return (cp - buf); |
1202 |
} |