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Commit | Line | Data |
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28f540f4 | 1 | /* |
28f540f4 RM |
2 | * Copyright (c) 1988, 1993 |
3 | * The Regents of the University of California. All rights reserved. | |
52ee6223 | 4 | * |
28f540f4 RM |
5 | * Redistribution and use in source and binary forms, with or without |
6 | * modification, are permitted provided that the following conditions | |
7 | * are met: | |
8 | * 1. Redistributions of source code must retain the above copyright | |
9 | * notice, this list of conditions and the following disclaimer. | |
10 | * 2. Redistributions in binary form must reproduce the above copyright | |
11 | * notice, this list of conditions and the following disclaimer in the | |
12 | * documentation and/or other materials provided with the distribution. | |
28f540f4 RM |
13 | * 4. Neither the name of the University nor the names of its contributors |
14 | * may be used to endorse or promote products derived from this software | |
15 | * without specific prior written permission. | |
52ee6223 | 16 | * |
28f540f4 RM |
17 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
18 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
19 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
20 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE | |
21 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | |
22 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | |
23 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | |
24 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT | |
25 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | |
26 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | |
27 | * SUCH DAMAGE. | |
b43b13ac UD |
28 | */ |
29 | ||
30 | /* | |
28f540f4 | 31 | * Portions Copyright (c) 1993 by Digital Equipment Corporation. |
52ee6223 | 32 | * |
28f540f4 RM |
33 | * Permission to use, copy, modify, and distribute this software for any |
34 | * purpose with or without fee is hereby granted, provided that the above | |
35 | * copyright notice and this permission notice appear in all copies, and that | |
36 | * the name of Digital Equipment Corporation not be used in advertising or | |
37 | * publicity pertaining to distribution of the document or software without | |
38 | * specific, written prior permission. | |
52ee6223 | 39 | * |
28f540f4 RM |
40 | * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL |
41 | * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES | |
42 | * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT | |
43 | * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL | |
44 | * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR | |
45 | * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS | |
46 | * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS | |
47 | * SOFTWARE. | |
b43b13ac UD |
48 | */ |
49 | ||
50 | /* | |
51 | * Portions Copyright (c) 1996-1999 by Internet Software Consortium. | |
52 | * | |
53 | * Permission to use, copy, modify, and distribute this software for any | |
54 | * purpose with or without fee is hereby granted, provided that the above | |
55 | * copyright notice and this permission notice appear in all copies. | |
56 | * | |
57 | * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS | |
58 | * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES | |
59 | * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE | |
60 | * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL | |
61 | * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR | |
62 | * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS | |
63 | * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS | |
64 | * SOFTWARE. | |
28f540f4 RM |
65 | */ |
66 | ||
acf82eaf | 67 | #include <assert.h> |
df21c858 | 68 | #include <sys/types.h> |
28f540f4 RM |
69 | #include <sys/param.h> |
70 | #include <netinet/in.h> | |
71 | #include <arpa/inet.h> | |
72 | #include <arpa/nameser.h> | |
28f540f4 RM |
73 | #include <ctype.h> |
74 | #include <errno.h> | |
b43b13ac UD |
75 | #include <netdb.h> |
76 | #include <resolv.h> | |
a7ff1da8 | 77 | #include <resolv/resolv-internal.h> |
352f4ff9 | 78 | #include <resolv/resolv_context.h> |
b43b13ac UD |
79 | #include <stdio.h> |
80 | #include <stdlib.h> | |
81 | #include <string.h> | |
03775117 | 82 | #include <shlib-compat.h> |
40c0add7 | 83 | #include <scratch_buffer.h> |
28f540f4 | 84 | |
e2dced82 | 85 | #if PACKETSZ > 65536 |
28f540f4 RM |
86 | #define MAXPACKET PACKETSZ |
87 | #else | |
e2dced82 | 88 | #define MAXPACKET 65536 |
28f540f4 RM |
89 | #endif |
90 | ||
0420d888 UD |
91 | #define QUERYSIZE (HFIXEDSZ + QFIXEDSZ + MAXCDNAME + 1) |
92 | ||
93 | static int | |
352f4ff9 FW |
94 | __res_context_querydomain (struct resolv_context *, |
95 | const char *name, const char *domain, | |
96 | int class, int type, unsigned char *answer, int anslen, | |
97 | unsigned char **answerp, unsigned char **answerp2, int *nanswerp2, | |
98 | int *resplen2, int *answerp2_malloced); | |
99 | ||
100 | /* Formulate a normal query, send, and await answer. Returned answer | |
101 | is placed in supplied buffer ANSWER. Perform preliminary check of | |
102 | answer, returning success only if no error is indicated and the | |
103 | answer count is nonzero. Return the size of the response on | |
104 | success, -1 on error. Error number is left in h_errno. | |
105 | ||
106 | Caller must parse answer and determine whether it answers the | |
107 | question. */ | |
28f540f4 | 108 | int |
352f4ff9 FW |
109 | __res_context_query (struct resolv_context *ctx, const char *name, |
110 | int class, int type, | |
111 | unsigned char *answer, int anslen, | |
112 | unsigned char **answerp, unsigned char **answerp2, | |
113 | int *nanswerp2, int *resplen2, int *answerp2_malloced) | |
28f540f4 | 114 | { |
352f4ff9 | 115 | struct __res_state *statp = ctx->resp; |
05dec22d JDA |
116 | UHEADER *hp = (UHEADER *) answer; |
117 | UHEADER *hp2; | |
40c0add7 AZ |
118 | int n; |
119 | ||
120 | /* It requires 2 times QUERYSIZE for type == T_QUERY_A_AND_AAAA. */ | |
121 | struct scratch_buffer buf; | |
122 | scratch_buffer_init (&buf); | |
123 | _Static_assert (2 * QUERYSIZE <= sizeof (buf.__space.__c), | |
124 | "scratch_buffer too small"); | |
125 | u_char *query1 = buf.data; | |
1eb946b9 UD |
126 | int nquery1 = -1; |
127 | u_char *query2 = NULL; | |
128 | int nquery2 = 0; | |
28f540f4 | 129 | |
2bbb7d5b UD |
130 | again: |
131 | hp->rcode = NOERROR; /* default */ | |
6166815d | 132 | |
fc82b0a2 | 133 | if (type == T_QUERY_A_AND_AAAA) |
1eb946b9 | 134 | { |
352f4ff9 | 135 | n = __res_context_mkquery (ctx, QUERY, name, class, T_A, NULL, |
40c0add7 | 136 | query1, buf.length); |
1eb946b9 UD |
137 | if (n > 0) |
138 | { | |
44500cbb | 139 | if ((statp->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0) |
44abc397 | 140 | { |
e14a2772 FW |
141 | /* Use RESOLV_EDNS_BUFFER_SIZE because the receive |
142 | buffer can be reallocated. */ | |
40c0add7 | 143 | n = __res_nopt (ctx, n, query1, buf.length, |
e14a2772 | 144 | RESOLV_EDNS_BUFFER_SIZE); |
44abc397 UD |
145 | if (n < 0) |
146 | goto unspec_nomem; | |
147 | } | |
1eb946b9 UD |
148 | |
149 | nquery1 = n; | |
40c0add7 | 150 | query2 = buf.data + n; |
352f4ff9 | 151 | n = __res_context_mkquery (ctx, QUERY, name, class, T_AAAA, |
40c0add7 | 152 | NULL, query2, buf.length - n); |
1eb946b9 | 153 | if (n > 0 |
2d0671cb | 154 | && (statp->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0) |
e14a2772 FW |
155 | /* Use RESOLV_EDNS_BUFFER_SIZE because the receive |
156 | buffer can be reallocated. */ | |
40c0add7 | 157 | n = __res_nopt (ctx, n, query2, buf.length, |
e14a2772 | 158 | RESOLV_EDNS_BUFFER_SIZE); |
1eb946b9 UD |
159 | nquery2 = n; |
160 | } | |
44abc397 UD |
161 | |
162 | unspec_nomem:; | |
1eb946b9 UD |
163 | } |
164 | else | |
165 | { | |
352f4ff9 | 166 | n = __res_context_mkquery (ctx, QUERY, name, class, type, NULL, |
40c0add7 | 167 | query1, buf.length); |
1eb946b9 UD |
168 | |
169 | if (n > 0 | |
2d0671cb | 170 | && (statp->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0) |
e14a2772 FW |
171 | { |
172 | /* Use RESOLV_EDNS_BUFFER_SIZE if the receive buffer | |
173 | can be reallocated. */ | |
174 | size_t advertise; | |
175 | if (answerp == NULL) | |
176 | advertise = anslen; | |
177 | else | |
178 | advertise = RESOLV_EDNS_BUFFER_SIZE; | |
40c0add7 | 179 | n = __res_nopt (ctx, n, query1, buf.length, advertise); |
e14a2772 | 180 | } |
1eb946b9 UD |
181 | |
182 | nquery1 = n; | |
183 | } | |
184 | ||
40c0add7 | 185 | if (__glibc_unlikely (n <= 0)) { |
0420d888 UD |
186 | /* Retry just in case res_nmkquery failed because of too |
187 | short buffer. Shouldn't happen. */ | |
40c0add7 AZ |
188 | if (scratch_buffer_set_array_size (&buf, |
189 | T_QUERY_A_AND_AAAA ? 2 : 1, | |
190 | MAXPACKET)) { | |
191 | query1 = buf.data; | |
2bbb7d5b | 192 | goto again; |
78512c00 | 193 | } |
0420d888 | 194 | } |
a1ffb40e | 195 | if (__glibc_unlikely (n <= 0)) { |
b43b13ac | 196 | RES_SET_H_ERRNO(statp, NO_RECOVERY); |
40c0add7 | 197 | scratch_buffer_free (&buf); |
28f540f4 RM |
198 | return (n); |
199 | } | |
f282cdbe FW |
200 | |
201 | /* Suppress AAAA lookups if required. __res_handle_no_aaaa | |
202 | checks RES_NOAAAA first, so avoids parsing the | |
203 | just-generated query packet in most cases. nss_dns avoids | |
204 | using T_QUERY_A_AND_AAAA in RES_NOAAAA mode, so there is no | |
205 | need to handle it here. */ | |
206 | if (type == T_AAAA && __res_handle_no_aaaa (ctx, query1, nquery1, | |
207 | answer, anslen, &n)) | |
208 | /* There must be no second query for AAAA queries. The code | |
209 | below is still needed to translate NODATA responses. */ | |
210 | assert (query2 == NULL); | |
211 | else | |
212 | { | |
213 | assert (answerp == NULL || (void *) *answerp == (void *) answer); | |
214 | n = __res_context_send (ctx, query1, nquery1, query2, nquery2, | |
215 | answer, anslen, | |
216 | answerp, answerp2, nanswerp2, resplen2, | |
217 | answerp2_malloced); | |
218 | } | |
219 | ||
40c0add7 | 220 | scratch_buffer_free (&buf); |
28f540f4 | 221 | if (n < 0) { |
b43b13ac | 222 | RES_SET_H_ERRNO(statp, TRY_AGAIN); |
28f540f4 RM |
223 | return (n); |
224 | } | |
225 | ||
acf82eaf | 226 | if (answerp != NULL) |
352f4ff9 | 227 | /* __res_context_send might have reallocated the buffer. */ |
05dec22d | 228 | hp = (UHEADER *) *answerp; |
acf82eaf | 229 | |
cc8bb21c AJ |
230 | /* We simplify the following tests by assigning HP to HP2 or |
231 | vice versa. It is easy to verify that this is the same as | |
232 | ignoring all tests of HP or HP2. */ | |
233 | if (answerp2 == NULL || *resplen2 < (int) sizeof (HEADER)) | |
5908f779 | 234 | { |
cc8bb21c | 235 | hp2 = hp; |
5908f779 | 236 | } |
cc8bb21c | 237 | else |
5908f779 | 238 | { |
05dec22d | 239 | hp2 = (UHEADER *) *answerp2; |
cc8bb21c AJ |
240 | if (n < (int) sizeof (HEADER)) |
241 | { | |
242 | hp = hp2; | |
243 | } | |
5908f779 UD |
244 | } |
245 | ||
cc8bb21c AJ |
246 | /* Make sure both hp and hp2 are defined */ |
247 | assert((hp != NULL) && (hp2 != NULL)); | |
248 | ||
1eb946b9 UD |
249 | if ((hp->rcode != NOERROR || ntohs(hp->ancount) == 0) |
250 | && (hp2->rcode != NOERROR || ntohs(hp2->ancount) == 0)) { | |
1eb946b9 | 251 | switch (hp->rcode == NOERROR ? hp2->rcode : hp->rcode) { |
28f540f4 | 252 | case NXDOMAIN: |
1eb946b9 UD |
253 | if ((hp->rcode == NOERROR && ntohs (hp->ancount) != 0) |
254 | || (hp2->rcode == NOERROR | |
255 | && ntohs (hp2->ancount) != 0)) | |
256 | goto success; | |
b43b13ac | 257 | RES_SET_H_ERRNO(statp, HOST_NOT_FOUND); |
28f540f4 RM |
258 | break; |
259 | case SERVFAIL: | |
b43b13ac | 260 | RES_SET_H_ERRNO(statp, TRY_AGAIN); |
28f540f4 RM |
261 | break; |
262 | case NOERROR: | |
1eb946b9 UD |
263 | if (ntohs (hp->ancount) != 0 |
264 | || ntohs (hp2->ancount) != 0) | |
265 | goto success; | |
b43b13ac | 266 | RES_SET_H_ERRNO(statp, NO_DATA); |
28f540f4 RM |
267 | break; |
268 | case FORMERR: | |
269 | case NOTIMP: | |
cf4f16cc UD |
270 | /* Servers must not reply to AAAA queries with |
271 | NOTIMP etc but some of them do. */ | |
272 | if ((hp->rcode == NOERROR && ntohs (hp->ancount) != 0) | |
273 | || (hp2->rcode == NOERROR | |
274 | && ntohs (hp2->ancount) != 0)) | |
275 | goto success; | |
276 | /* FALLTHROUGH */ | |
28f540f4 RM |
277 | case REFUSED: |
278 | default: | |
b43b13ac | 279 | RES_SET_H_ERRNO(statp, NO_RECOVERY); |
28f540f4 RM |
280 | break; |
281 | } | |
282 | return (-1); | |
283 | } | |
1eb946b9 | 284 | success: |
28f540f4 RM |
285 | return (n); |
286 | } | |
ea9878ec | 287 | libc_hidden_def (__res_context_query) |
352f4ff9 FW |
288 | |
289 | /* Common part of res_nquery and res_query. */ | |
290 | static int | |
291 | context_query_common (struct resolv_context *ctx, | |
292 | const char *name, int class, int type, | |
293 | unsigned char *answer, int anslen) | |
294 | { | |
295 | if (ctx == NULL) | |
296 | { | |
297 | RES_SET_H_ERRNO (&_res, NETDB_INTERNAL); | |
298 | return -1; | |
299 | } | |
300 | int result = __res_context_query (ctx, name, class, type, answer, anslen, | |
301 | NULL, NULL, NULL, NULL, NULL); | |
302 | __resolv_context_put (ctx); | |
303 | return result; | |
304 | } | |
28f540f4 | 305 | |
0420d888 | 306 | int |
ea9878ec FW |
307 | ___res_nquery (res_state statp, |
308 | const char *name, /* Domain name. */ | |
309 | int class, int type, /* Class and type of query. */ | |
310 | unsigned char *answer, /* Buffer to put answer. */ | |
311 | int anslen) /* Size of answer buffer. */ | |
0420d888 | 312 | { |
352f4ff9 FW |
313 | return context_query_common |
314 | (__resolv_context_get_override (statp), name, class, type, answer, anslen); | |
0420d888 | 315 | } |
ea9878ec FW |
316 | versioned_symbol (libc, ___res_nquery, res_nquery, GLIBC_2_34); |
317 | #if OTHER_SHLIB_COMPAT (libresolv, GLIBC_2_2, GLIBC_2_34) | |
318 | compat_symbol (libresolv, ___res_nquery, __res_nquery, GLIBC_2_2); | |
319 | #endif | |
0420d888 | 320 | |
03775117 | 321 | int |
ea9878ec FW |
322 | ___res_query (const char *name, int class, int type, |
323 | unsigned char *answer, int anslen) | |
03775117 | 324 | { |
352f4ff9 FW |
325 | return context_query_common |
326 | (__resolv_context_get (), name, class, type, answer, anslen); | |
03775117 | 327 | } |
ea9878ec FW |
328 | versioned_symbol (libc, ___res_query, res_query, GLIBC_2_34); |
329 | #if OTHER_SHLIB_COMPAT (libresolv, GLIBC_2_0, GLIBC_2_2) | |
330 | compat_symbol (libresolv, ___res_query, res_query, GLIBC_2_0); | |
331 | #endif | |
332 | #if OTHER_SHLIB_COMPAT (libresolv, GLIBC_2_2, GLIBC_2_34) | |
333 | compat_symbol (libresolv, ___res_query, __res_query, GLIBC_2_2); | |
334 | #endif | |
03775117 | 335 | |
352f4ff9 FW |
336 | /* Formulate a normal query, send, and retrieve answer in supplied |
337 | buffer. Return the size of the response on success, -1 on error. | |
338 | If enabled, implement search rules until answer or unrecoverable | |
339 | failure is detected. Error code, if any, is left in h_errno. */ | |
28f540f4 | 340 | int |
352f4ff9 FW |
341 | __res_context_search (struct resolv_context *ctx, |
342 | const char *name, int class, int type, | |
343 | unsigned char *answer, int anslen, | |
344 | unsigned char **answerp, unsigned char **answerp2, | |
345 | int *nanswerp2, int *resplen2, int *answerp2_malloced) | |
28f540f4 | 346 | { |
352f4ff9 | 347 | struct __res_state *statp = ctx->resp; |
3f853f22 | 348 | const char *cp; |
05dec22d | 349 | UHEADER *hp = (UHEADER *) answer; |
b43b13ac | 350 | char tmp[NS_MAXDNAME]; |
28f540f4 | 351 | u_int dots; |
e685e07d | 352 | int trailing_dot, ret, saved_herrno; |
b43b13ac | 353 | int got_nodata = 0, got_servfail = 0, root_on_list = 0; |
e685e07d | 354 | int tried_as_is = 0; |
f87dfb1f | 355 | int searched = 0; |
28f540f4 | 356 | |
c4029823 | 357 | __set_errno (0); |
b43b13ac UD |
358 | RES_SET_H_ERRNO(statp, HOST_NOT_FOUND); /* True if we never query. */ |
359 | ||
28f540f4 | 360 | dots = 0; |
b43b13ac | 361 | for (cp = name; *cp != '\0'; cp++) |
28f540f4 RM |
362 | dots += (*cp == '.'); |
363 | trailing_dot = 0; | |
364 | if (cp > name && *--cp == '.') | |
365 | trailing_dot++; | |
366 | ||
b43b13ac | 367 | /* If there aren't any dots, it could be a user-level alias. */ |
352f4ff9 FW |
368 | if (!dots && (cp = __res_context_hostalias |
369 | (ctx, name, tmp, sizeof tmp))!= NULL) | |
370 | return __res_context_query (ctx, cp, class, type, answer, | |
371 | anslen, answerp, answerp2, | |
372 | nanswerp2, resplen2, answerp2_malloced); | |
28f540f4 RM |
373 | |
374 | /* | |
e685e07d UD |
375 | * If there are enough dots in the name, let's just give it a |
376 | * try 'as is'. The threshold can be set with the "ndots" option. | |
377 | * Also, query 'as is', if there is a trailing dot in the name. | |
28f540f4 | 378 | */ |
e685e07d UD |
379 | saved_herrno = -1; |
380 | if (dots >= statp->ndots || trailing_dot) { | |
352f4ff9 FW |
381 | ret = __res_context_querydomain (ctx, name, NULL, class, type, |
382 | answer, anslen, answerp, | |
383 | answerp2, nanswerp2, resplen2, | |
384 | answerp2_malloced); | |
16b293a7 SP |
385 | if (ret > 0 || trailing_dot |
386 | /* If the second response is valid then we use that. */ | |
e35c53e3 | 387 | || (ret == 0 && resplen2 != NULL && *resplen2 > 0)) |
e685e07d UD |
388 | return (ret); |
389 | saved_herrno = h_errno; | |
390 | tried_as_is++; | |
0420d888 UD |
391 | if (answerp && *answerp != answer) { |
392 | answer = *answerp; | |
393 | anslen = MAXPACKET; | |
394 | } | |
ab09bf61 | 395 | if (answerp2 && *answerp2_malloced) |
1eb946b9 UD |
396 | { |
397 | free (*answerp2); | |
398 | *answerp2 = NULL; | |
e9db92d3 | 399 | *nanswerp2 = 0; |
ab09bf61 | 400 | *answerp2_malloced = 0; |
1eb946b9 | 401 | } |
e685e07d | 402 | } |
28f540f4 RM |
403 | |
404 | /* | |
405 | * We do at least one level of search if | |
406 | * - there is no dot and RES_DEFNAME is set, or | |
407 | * - there is at least one dot, there is no trailing dot, | |
408 | * and RES_DNSRCH is set. | |
409 | */ | |
b43b13ac UD |
410 | if ((!dots && (statp->options & RES_DEFNAMES) != 0) || |
411 | (dots && !trailing_dot && (statp->options & RES_DNSRCH) != 0)) { | |
28f540f4 RM |
412 | int done = 0; |
413 | ||
3f853f22 FW |
414 | for (size_t domain_index = 0; !done; ++domain_index) { |
415 | const char *dname = __resolv_context_search_list | |
416 | (ctx, domain_index); | |
417 | if (dname == NULL) | |
418 | break; | |
f87dfb1f | 419 | searched = 1; |
28f540f4 | 420 | |
352f4ff9 | 421 | /* __res_context_querydoman concatenates name |
b59d114b AO |
422 | with dname with a "." in between. If we |
423 | pass it in dname the "." we got from the | |
424 | configured default search path, we'll end | |
425 | up with "name..", which won't resolve. | |
426 | OTOH, passing it "" will result in "name.", | |
427 | which has the intended effect for both | |
428 | possible representations of the root | |
429 | domain. */ | |
430 | if (dname[0] == '.') | |
431 | dname++; | |
432 | if (dname[0] == '\0') | |
b43b13ac UD |
433 | root_on_list++; |
434 | ||
352f4ff9 FW |
435 | ret = __res_context_querydomain |
436 | (ctx, name, dname, class, type, | |
437 | answer, anslen, answerp, answerp2, nanswerp2, | |
438 | resplen2, answerp2_malloced); | |
e35c53e3 SP |
439 | if (ret > 0 || (ret == 0 && resplen2 != NULL |
440 | && *resplen2 > 0)) | |
28f540f4 RM |
441 | return (ret); |
442 | ||
0420d888 UD |
443 | if (answerp && *answerp != answer) { |
444 | answer = *answerp; | |
445 | anslen = MAXPACKET; | |
446 | } | |
ab09bf61 | 447 | if (answerp2 && *answerp2_malloced) |
1eb946b9 UD |
448 | { |
449 | free (*answerp2); | |
450 | *answerp2 = NULL; | |
e9db92d3 | 451 | *nanswerp2 = 0; |
ab09bf61 | 452 | *answerp2_malloced = 0; |
1eb946b9 | 453 | } |
0420d888 | 454 | |
28f540f4 RM |
455 | /* |
456 | * If no server present, give up. | |
457 | * If name isn't found in this domain, | |
458 | * keep trying higher domains in the search list | |
459 | * (if that's enabled). | |
460 | * On a NO_DATA error, keep trying, otherwise | |
461 | * a wildcard entry of another type could keep us | |
462 | * from finding this entry higher in the domain. | |
463 | * If we get some other error (negative answer or | |
464 | * server failure), then stop searching up, | |
465 | * but try the input name below in case it's | |
466 | * fully-qualified. | |
467 | */ | |
468 | if (errno == ECONNREFUSED) { | |
b43b13ac | 469 | RES_SET_H_ERRNO(statp, TRY_AGAIN); |
28f540f4 RM |
470 | return (-1); |
471 | } | |
472 | ||
b43b13ac | 473 | switch (statp->res_h_errno) { |
28f540f4 RM |
474 | case NO_DATA: |
475 | got_nodata++; | |
476 | /* FALLTHROUGH */ | |
477 | case HOST_NOT_FOUND: | |
478 | /* keep trying */ | |
479 | break; | |
480 | case TRY_AGAIN: | |
481 | if (hp->rcode == SERVFAIL) { | |
482 | /* try next search element, if any */ | |
483 | got_servfail++; | |
484 | break; | |
485 | } | |
486 | /* FALLTHROUGH */ | |
487 | default: | |
488 | /* anything else implies that we're done */ | |
489 | done++; | |
490 | } | |
491 | ||
492 | /* if we got here for some reason other than DNSRCH, | |
493 | * we only wanted one iteration of the loop, so stop. | |
494 | */ | |
b43b13ac | 495 | if ((statp->options & RES_DNSRCH) == 0) |
28f540f4 RM |
496 | done++; |
497 | } | |
498 | } | |
499 | ||
b43b13ac | 500 | /* |
c12e9f37 | 501 | * If the query has not already been tried as is then try it |
f87dfb1f | 502 | * unless RES_NOTLDQUERY is set and there were no dots. |
28f540f4 | 503 | */ |
f87dfb1f UD |
504 | if ((dots || !searched || (statp->options & RES_NOTLDQUERY) == 0) |
505 | && !(tried_as_is || root_on_list)) { | |
352f4ff9 FW |
506 | ret = __res_context_querydomain |
507 | (ctx, name, NULL, class, type, | |
508 | answer, anslen, answerp, answerp2, nanswerp2, | |
509 | resplen2, answerp2_malloced); | |
e35c53e3 SP |
510 | if (ret > 0 || (ret == 0 && resplen2 != NULL |
511 | && *resplen2 > 0)) | |
28f540f4 RM |
512 | return (ret); |
513 | } | |
514 | ||
515 | /* if we got here, we didn't satisfy the search. | |
b43b13ac | 516 | * if we did an initial full query, return that query's H_ERRNO |
28f540f4 RM |
517 | * (note that we wouldn't be here if that query had succeeded). |
518 | * else if we ever got a nodata, send that back as the reason. | |
b43b13ac | 519 | * else send back meaningless H_ERRNO, that being the one from |
28f540f4 RM |
520 | * the last DNSRCH we did. |
521 | */ | |
ab09bf61 | 522 | if (answerp2 && *answerp2_malloced) |
1eb946b9 UD |
523 | { |
524 | free (*answerp2); | |
525 | *answerp2 = NULL; | |
e9db92d3 | 526 | *nanswerp2 = 0; |
ab09bf61 | 527 | *answerp2_malloced = 0; |
1eb946b9 | 528 | } |
e685e07d UD |
529 | if (saved_herrno != -1) |
530 | RES_SET_H_ERRNO(statp, saved_herrno); | |
531 | else if (got_nodata) | |
b43b13ac | 532 | RES_SET_H_ERRNO(statp, NO_DATA); |
28f540f4 | 533 | else if (got_servfail) |
b43b13ac | 534 | RES_SET_H_ERRNO(statp, TRY_AGAIN); |
28f540f4 RM |
535 | return (-1); |
536 | } | |
ea9878ec | 537 | libc_hidden_def (__res_context_search) |
352f4ff9 FW |
538 | |
539 | /* Common part of res_nsearch and res_search. */ | |
540 | static int | |
541 | context_search_common (struct resolv_context *ctx, | |
542 | const char *name, int class, int type, | |
543 | unsigned char *answer, int anslen) | |
544 | { | |
545 | if (ctx == NULL) | |
546 | { | |
547 | RES_SET_H_ERRNO (&_res, NETDB_INTERNAL); | |
548 | return -1; | |
549 | } | |
550 | int result = __res_context_search (ctx, name, class, type, answer, anslen, | |
551 | NULL, NULL, NULL, NULL, NULL); | |
552 | __resolv_context_put (ctx); | |
553 | return result; | |
554 | } | |
28f540f4 | 555 | |
0420d888 | 556 | int |
ea9878ec FW |
557 | ___res_nsearch (res_state statp, |
558 | const char *name, /* Domain name. */ | |
559 | int class, int type, /* Class and type of query. */ | |
560 | unsigned char *answer, /* Buffer to put answer. */ | |
561 | int anslen) /* Size of answer. */ | |
0420d888 | 562 | { |
352f4ff9 FW |
563 | return context_search_common |
564 | (__resolv_context_get_override (statp), name, class, type, answer, anslen); | |
0420d888 | 565 | } |
ea9878ec FW |
566 | versioned_symbol (libc, ___res_nsearch, res_nsearch, GLIBC_2_34); |
567 | #if OTHER_SHLIB_COMPAT (libresolv, GLIBC_2_2, GLIBC_2_34) | |
568 | compat_symbol (libresolv, ___res_nsearch, __res_nsearch, GLIBC_2_2); | |
569 | #endif | |
0420d888 | 570 | |
03775117 | 571 | int |
ea9878ec FW |
572 | ___res_search (const char *name, int class, int type, |
573 | unsigned char *answer, int anslen) | |
03775117 | 574 | { |
352f4ff9 FW |
575 | return context_search_common |
576 | (__resolv_context_get (), name, class, type, answer, anslen); | |
03775117 | 577 | } |
ea9878ec FW |
578 | versioned_symbol (libc, ___res_search, res_search, GLIBC_2_34); |
579 | #if OTHER_SHLIB_COMPAT (libresolv, GLIBC_2_0, GLIBC_2_2) | |
580 | compat_symbol (libresolv, ___res_search, res_search, GLIBC_2_0); | |
581 | #endif | |
582 | #if OTHER_SHLIB_COMPAT (libresolv, GLIBC_2_2, GLIBC_2_34) | |
583 | compat_symbol (libresolv, ___res_search, __res_search, GLIBC_2_2); | |
584 | #endif | |
03775117 | 585 | |
352f4ff9 FW |
586 | /* Perform a call on res_query on the concatenation of name and |
587 | domain. */ | |
0420d888 | 588 | static int |
352f4ff9 FW |
589 | __res_context_querydomain (struct resolv_context *ctx, |
590 | const char *name, const char *domain, | |
591 | int class, int type, | |
592 | unsigned char *answer, int anslen, | |
593 | unsigned char **answerp, unsigned char **answerp2, | |
594 | int *nanswerp2, int *resplen2, | |
595 | int *answerp2_malloced) | |
28f540f4 | 596 | { |
352f4ff9 | 597 | struct __res_state *statp = ctx->resp; |
b43b13ac | 598 | char nbuf[MAXDNAME]; |
28f540f4 | 599 | const char *longname = nbuf; |
28b59fca | 600 | size_t n, d; |
28f540f4 | 601 | |
28f540f4 | 602 | if (domain == NULL) { |
b43b13ac | 603 | n = strlen(name); |
8fdceb2e JL |
604 | |
605 | /* Decrement N prior to checking it against MAXDNAME | |
606 | so that we detect a wrap to SIZE_MAX and return | |
607 | a reasonable error. */ | |
608 | n--; | |
609 | if (n >= MAXDNAME - 1) { | |
b43b13ac UD |
610 | RES_SET_H_ERRNO(statp, NO_RECOVERY); |
611 | return (-1); | |
612 | } | |
f3d945d5 | 613 | longname = name; |
b43b13ac UD |
614 | } else { |
615 | n = strlen(name); | |
616 | d = strlen(domain); | |
617 | if (n + d + 1 >= MAXDNAME) { | |
618 | RES_SET_H_ERRNO(statp, NO_RECOVERY); | |
619 | return (-1); | |
620 | } | |
eb73b878 MS |
621 | char *p = __stpcpy (nbuf, name); |
622 | *p++ = '.'; | |
623 | strcpy (p, domain); | |
b43b13ac | 624 | } |
352f4ff9 FW |
625 | return __res_context_query (ctx, longname, class, type, answer, |
626 | anslen, answerp, answerp2, nanswerp2, | |
627 | resplen2, answerp2_malloced); | |
628 | } | |
629 | ||
630 | /* Common part of res_nquerydomain and res_querydomain. */ | |
631 | static int | |
632 | context_querydomain_common (struct resolv_context *ctx, | |
633 | const char *name, const char *domain, | |
634 | int class, int type, | |
635 | unsigned char *answer, int anslen) | |
636 | { | |
637 | if (ctx == NULL) | |
638 | { | |
639 | RES_SET_H_ERRNO (&_res, NETDB_INTERNAL); | |
640 | return -1; | |
641 | } | |
642 | int result = __res_context_querydomain (ctx, name, domain, class, type, | |
643 | answer, anslen, | |
644 | NULL, NULL, NULL, NULL, NULL); | |
645 | __resolv_context_put (ctx); | |
646 | return result; | |
0420d888 UD |
647 | } |
648 | ||
649 | int | |
ea9878ec FW |
650 | ___res_nquerydomain (res_state statp, |
651 | const char *name, | |
652 | const char *domain, | |
653 | int class, int type, /* Class and type of query. */ | |
654 | unsigned char *answer, /* Buffer to put answer. */ | |
655 | int anslen) /* Size of answer. */ | |
0420d888 | 656 | { |
352f4ff9 FW |
657 | return context_querydomain_common |
658 | (__resolv_context_get_override (statp), | |
659 | name, domain, class, type, answer, anslen); | |
28f540f4 | 660 | } |
ea9878ec FW |
661 | versioned_symbol (libc, ___res_nquerydomain, res_nquerydomain, GLIBC_2_34); |
662 | #if OTHER_SHLIB_COMPAT (libresolv, GLIBC_2_2, GLIBC_2_34) | |
663 | compat_symbol (libresolv, ___res_nquerydomain, __res_nquerydomain, GLIBC_2_2); | |
664 | #endif | |
28f540f4 | 665 | |
03775117 | 666 | int |
ea9878ec FW |
667 | ___res_querydomain (const char *name, const char *domain, int class, int type, |
668 | unsigned char *answer, int anslen) | |
03775117 | 669 | { |
352f4ff9 FW |
670 | return context_querydomain_common |
671 | (__resolv_context_get (), name, domain, class, type, answer, anslen); | |
03775117 | 672 | } |
ea9878ec FW |
673 | versioned_symbol (libc, ___res_querydomain, res_querydomain, GLIBC_2_34); |
674 | #if OTHER_SHLIB_COMPAT (libresolv, GLIBC_2_0, GLIBC_2_2) | |
675 | compat_symbol (libresolv, ___res_querydomain, res_querydomain, GLIBC_2_0); | |
676 | #endif | |
677 | #if OTHER_SHLIB_COMPAT (libresolv, GLIBC_2_2, GLIBC_2_34) | |
678 | compat_symbol (libresolv, ___res_querydomain, __res_querydomain, GLIBC_2_2); | |
03775117 | 679 | #endif |