1 | /* |
2 | * ++Copyright++ 1985, 1988, 1993 |
3 | * - |
4 | * Copyright (c) 1985, 1988, 1993 |
5 | * The Regents of the University of California. All rights reserved. |
6 | * |
7 | * Redistribution and use in source and binary forms, with or without |
8 | * modification, are permitted provided that the following conditions |
9 | * are met: |
10 | * 1. Redistributions of source code must retain the above copyright |
11 | * notice, this list of conditions and the following disclaimer. |
12 | * 2. Redistributions in binary form must reproduce the above copyright |
13 | * notice, this list of conditions and the following disclaimer in the |
14 | * documentation and/or other materials provided with the distribution. |
15 | * 4. Neither the name of the University nor the names of its contributors |
16 | * may be used to endorse or promote products derived from this software |
17 | * without specific prior written permission. |
18 | * |
19 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
20 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
21 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
22 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
23 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
24 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
25 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
26 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
27 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
28 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
29 | * SUCH DAMAGE. |
30 | * - |
31 | * Portions Copyright (c) 1993 by Digital Equipment Corporation. |
32 | * |
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. |
39 | * |
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. |
48 | * - |
49 | * --Copyright-- |
50 | */ |
51 | |
52 | /* XXX This file is not used by any of the resolver functions implemented by |
53 | glibc (i.e. get*info and gethostby*). It cannot be removed however because |
54 | it exports symbols in the libresolv ABI. The file is not maintained any |
55 | more, nor are these functions. */ |
56 | |
57 | #include <shlib-compat.h> |
58 | #if SHLIB_COMPAT (libresolv, GLIBC_2_0, GLIBC_2_25) |
59 | |
60 | # include <sys/types.h> |
61 | # include <sys/param.h> |
62 | # include <sys/socket.h> |
63 | # include <netinet/in.h> |
64 | # include <arpa/inet.h> |
65 | # include <arpa/nameser.h> |
66 | |
67 | # include <stdio.h> |
68 | # include <netdb.h> |
69 | # include <resolv/resolv-internal.h> |
70 | # include <resolv/resolv_context.h> |
71 | # include <ctype.h> |
72 | # include <errno.h> |
73 | # include <stdlib.h> |
74 | # include <string.h> |
75 | |
76 | # define MAXALIASES 35 |
77 | # define MAXADDRS 35 |
78 | |
79 | static char *h_addr_ptrs[MAXADDRS + 1]; |
80 | |
81 | static struct hostent host; |
82 | static char *host_aliases[MAXALIASES]; |
83 | static char hostbuf[8*1024]; |
84 | static u_char host_addr[16]; /* IPv4 or IPv6 */ |
85 | static FILE *hostf = NULL; |
86 | static int stayopen = 0; |
87 | |
88 | static struct hostent *res_gethostbyname2_context (struct resolv_context *, |
89 | const char *name, int af); |
90 | |
91 | static void map_v4v6_address (const char *src, char *dst) __THROW; |
92 | static void map_v4v6_hostent (struct hostent *hp, char **bp, int *len) __THROW; |
93 | |
94 | extern void addrsort (char **, int) __THROW; |
95 | |
96 | # if PACKETSZ > 65536 |
97 | # define MAXPACKET PACKETSZ |
98 | # else |
99 | # define MAXPACKET 65536 |
100 | # endif |
101 | |
102 | /* As per RFC 1034 and 1035 a host name cannot exceed 255 octets in length. */ |
103 | # ifdef MAXHOSTNAMELEN |
104 | # undef MAXHOSTNAMELEN |
105 | # endif |
106 | # define MAXHOSTNAMELEN 256 |
107 | |
108 | typedef union { |
109 | HEADER hdr; |
110 | u_char buf[MAXPACKET]; |
111 | } querybuf; |
112 | |
113 | typedef union { |
114 | int32_t al; |
115 | char ac; |
116 | } align; |
117 | |
118 | # ifndef h_errno |
119 | extern int h_errno; |
120 | # endif |
121 | |
122 | # define BOUNDED_INCR(x) \ |
123 | do { \ |
124 | cp += x; \ |
125 | if (cp > eom) { \ |
126 | __set_h_errno (NO_RECOVERY); \ |
127 | return (NULL); \ |
128 | } \ |
129 | } while (0) |
130 | |
131 | # define BOUNDS_CHECK(ptr, count) \ |
132 | do { \ |
133 | if ((ptr) + (count) > eom) { \ |
134 | __set_h_errno (NO_RECOVERY); \ |
135 | return (NULL); \ |
136 | } \ |
137 | } while (0) |
138 | |
139 | |
140 | static struct hostent * |
141 | getanswer (const querybuf *answer, int anslen, const char *qname, int qtype) |
142 | { |
143 | const HEADER *hp; |
144 | const u_char *cp; |
145 | int n; |
146 | const u_char *eom, *erdata; |
147 | char *bp, **ap, **hap; |
148 | int type, class, buflen, ancount, qdcount; |
149 | int haveanswer, had_error; |
150 | char tbuf[MAXDNAME]; |
151 | const char *tname; |
152 | int (*name_ok) (const char *); |
153 | |
154 | tname = qname; |
155 | host.h_name = NULL; |
156 | eom = answer->buf + anslen; |
157 | switch (qtype) { |
158 | case T_A: |
159 | case T_AAAA: |
160 | name_ok = res_hnok; |
161 | break; |
162 | case T_PTR: |
163 | name_ok = res_dnok; |
164 | break; |
165 | default: |
166 | return (NULL); /* XXX should be abort(); */ |
167 | } |
168 | /* |
169 | * find first satisfactory answer |
170 | */ |
171 | hp = &answer->hdr; |
172 | ancount = ntohs(hp->ancount); |
173 | qdcount = ntohs(hp->qdcount); |
174 | bp = hostbuf; |
175 | buflen = sizeof hostbuf; |
176 | cp = answer->buf; |
177 | BOUNDED_INCR(HFIXEDSZ); |
178 | if (qdcount != 1) { |
179 | __set_h_errno (NO_RECOVERY); |
180 | return (NULL); |
181 | } |
182 | n = dn_expand(answer->buf, eom, cp, bp, buflen); |
183 | if ((n < 0) || !(*name_ok)(bp)) { |
184 | __set_h_errno (NO_RECOVERY); |
185 | return (NULL); |
186 | } |
187 | BOUNDED_INCR(n + QFIXEDSZ); |
188 | if (qtype == T_A || qtype == T_AAAA) { |
189 | /* res_send() has already verified that the query name is the |
190 | * same as the one we sent; this just gets the expanded name |
191 | * (i.e., with the succeeding search-domain tacked on). |
192 | */ |
193 | n = strlen(bp) + 1; /* for the \0 */ |
194 | if (n >= MAXHOSTNAMELEN) { |
195 | __set_h_errno (NO_RECOVERY); |
196 | return (NULL); |
197 | } |
198 | host.h_name = bp; |
199 | bp += n; |
200 | buflen -= n; |
201 | /* The qname can be abbreviated, but h_name is now absolute. */ |
202 | qname = host.h_name; |
203 | } |
204 | ap = host_aliases; |
205 | *ap = NULL; |
206 | host.h_aliases = host_aliases; |
207 | hap = h_addr_ptrs; |
208 | *hap = NULL; |
209 | host.h_addr_list = h_addr_ptrs; |
210 | haveanswer = 0; |
211 | had_error = 0; |
212 | while (ancount-- > 0 && cp < eom && !had_error) { |
213 | n = dn_expand(answer->buf, eom, cp, bp, buflen); |
214 | if ((n < 0) || !(*name_ok)(bp)) { |
215 | had_error++; |
216 | continue; |
217 | } |
218 | cp += n; /* name */ |
219 | BOUNDS_CHECK(cp, 3 * INT16SZ + INT32SZ); |
220 | type = ns_get16(cp); |
221 | cp += INT16SZ; /* type */ |
222 | class = ns_get16(cp); |
223 | cp += INT16SZ + INT32SZ; /* class, TTL */ |
224 | n = ns_get16(cp); |
225 | cp += INT16SZ; /* len */ |
226 | BOUNDS_CHECK(cp, n); |
227 | erdata = cp + n; |
228 | if (class != C_IN) { |
229 | /* XXX - debug? syslog? */ |
230 | cp += n; |
231 | continue; /* XXX - had_error++ ? */ |
232 | } |
233 | if ((qtype == T_A || qtype == T_AAAA) && type == T_CNAME) { |
234 | if (ap >= &host_aliases[MAXALIASES-1]) |
235 | continue; |
236 | n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); |
237 | if ((n < 0) || !(*name_ok)(tbuf)) { |
238 | had_error++; |
239 | continue; |
240 | } |
241 | cp += n; |
242 | if (cp != erdata) { |
243 | __set_h_errno (NO_RECOVERY); |
244 | return (NULL); |
245 | } |
246 | /* Store alias. */ |
247 | *ap++ = bp; |
248 | n = strlen(bp) + 1; /* for the \0 */ |
249 | if (n >= MAXHOSTNAMELEN) { |
250 | had_error++; |
251 | continue; |
252 | } |
253 | bp += n; |
254 | buflen -= n; |
255 | /* Get canonical name. */ |
256 | n = strlen(tbuf) + 1; /* for the \0 */ |
257 | if (n > buflen || n >= MAXHOSTNAMELEN) { |
258 | had_error++; |
259 | continue; |
260 | } |
261 | strcpy(bp, tbuf); |
262 | host.h_name = bp; |
263 | bp += n; |
264 | buflen -= n; |
265 | continue; |
266 | } |
267 | if (qtype == T_PTR && type == T_CNAME) { |
268 | n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf); |
269 | if (n < 0 || !res_dnok(tbuf)) { |
270 | had_error++; |
271 | continue; |
272 | } |
273 | cp += n; |
274 | if (cp != erdata) { |
275 | __set_h_errno (NO_RECOVERY); |
276 | return (NULL); |
277 | } |
278 | /* Get canonical name. */ |
279 | n = strlen(tbuf) + 1; /* for the \0 */ |
280 | if (n > buflen || n >= MAXHOSTNAMELEN) { |
281 | had_error++; |
282 | continue; |
283 | } |
284 | strcpy(bp, tbuf); |
285 | tname = bp; |
286 | bp += n; |
287 | buflen -= n; |
288 | continue; |
289 | } |
290 | if (type != qtype) { |
291 | /* Log a low priority message if we get an unexpected |
292 | * record, but skip it if we are using DNSSEC since it |
293 | * uses many different types in responses that do not |
294 | * match QTYPE. |
295 | */ |
296 | cp += n; |
297 | continue; /* XXX - had_error++ ? */ |
298 | } |
299 | switch (type) { |
300 | case T_PTR: |
301 | if (strcasecmp(tname, bp) != 0) { |
302 | cp += n; |
303 | continue; /* XXX - had_error++ ? */ |
304 | } |
305 | n = dn_expand(answer->buf, eom, cp, bp, buflen); |
306 | if ((n < 0) || !res_hnok(bp)) { |
307 | had_error++; |
308 | break; |
309 | } |
310 | cp += n; |
311 | if (cp != erdata) { |
312 | __set_h_errno (NO_RECOVERY); |
313 | return (NULL); |
314 | } |
315 | if (!haveanswer) |
316 | host.h_name = bp; |
317 | else if (ap < &host_aliases[MAXALIASES-1]) |
318 | *ap++ = bp; |
319 | else |
320 | n = -1; |
321 | if (n != -1) { |
322 | n = strlen(bp) + 1; /* for the \0 */ |
323 | if (n >= MAXHOSTNAMELEN) { |
324 | had_error++; |
325 | break; |
326 | } |
327 | bp += n; |
328 | buflen -= n; |
329 | } |
330 | break; |
331 | case T_A: |
332 | case T_AAAA: |
333 | if (strcasecmp(host.h_name, bp) != 0) { |
334 | cp += n; |
335 | continue; /* XXX - had_error++ ? */ |
336 | } |
337 | if (n != host.h_length) { |
338 | cp += n; |
339 | continue; |
340 | } |
341 | if (!haveanswer) { |
342 | int nn; |
343 | |
344 | host.h_name = bp; |
345 | nn = strlen(bp) + 1; /* for the \0 */ |
346 | bp += nn; |
347 | buflen -= nn; |
348 | } |
349 | |
350 | /* XXX: when incrementing bp, we have to decrement |
351 | * buflen by the same amount --okir */ |
352 | buflen -= sizeof(align) - ((u_long)bp % sizeof(align)); |
353 | |
354 | bp += sizeof(align) - ((u_long)bp % sizeof(align)); |
355 | |
356 | if (bp + n >= &hostbuf[sizeof hostbuf]) { |
357 | had_error++; |
358 | continue; |
359 | } |
360 | if (hap >= &h_addr_ptrs[MAXADDRS-1]) { |
361 | cp += n; |
362 | continue; |
363 | } |
364 | memmove(*hap++ = bp, cp, n); |
365 | bp += n; |
366 | buflen -= n; |
367 | cp += n; |
368 | if (cp != erdata) { |
369 | __set_h_errno (NO_RECOVERY); |
370 | return (NULL); |
371 | } |
372 | break; |
373 | default: |
374 | abort(); |
375 | } |
376 | if (!had_error) |
377 | haveanswer++; |
378 | } |
379 | if (haveanswer) { |
380 | *ap = NULL; |
381 | *hap = NULL; |
382 | /* |
383 | * Note: we sort even if host can take only one address |
384 | * in its return structures - should give it the "best" |
385 | * address in that case, not some random one |
386 | */ |
387 | if (_res.nsort && haveanswer > 1 && qtype == T_A) |
388 | addrsort(h_addr_ptrs, haveanswer); |
389 | if (!host.h_name) { |
390 | n = strlen(qname) + 1; /* for the \0 */ |
391 | if (n > buflen || n >= MAXHOSTNAMELEN) |
392 | goto no_recovery; |
393 | strcpy(bp, qname); |
394 | host.h_name = bp; |
395 | bp += n; |
396 | buflen -= n; |
397 | } |
398 | if (res_use_inet6 ()) |
399 | map_v4v6_hostent(&host, &bp, &buflen); |
400 | __set_h_errno (NETDB_SUCCESS); |
401 | return (&host); |
402 | } |
403 | no_recovery: |
404 | __set_h_errno (NO_RECOVERY); |
405 | return (NULL); |
406 | } |
407 | |
408 | extern struct hostent *res_gethostbyname2(const char *name, int af); |
409 | libresolv_hidden_proto (res_gethostbyname2) |
410 | |
411 | struct hostent * |
412 | res_gethostbyname (const char *name) |
413 | { |
414 | struct resolv_context *ctx = __resolv_context_get (); |
415 | if (ctx == NULL) |
416 | { |
417 | __set_h_errno (NETDB_INTERNAL); |
418 | return NULL; |
419 | } |
420 | |
421 | if (res_use_inet6 ()) |
422 | { |
423 | struct hostent *hp = res_gethostbyname2_context (ctx, name, AF_INET6); |
424 | if (hp != NULL) |
425 | { |
426 | __resolv_context_put (ctx); |
427 | return hp; |
428 | } |
429 | } |
430 | struct hostent *hp = res_gethostbyname2_context (ctx, name, AF_INET); |
431 | __resolv_context_put (ctx); |
432 | return hp; |
433 | } |
434 | compat_symbol (libresolv, res_gethostbyname, res_gethostbyname, GLIBC_2_0); |
435 | |
436 | static struct hostent * |
437 | res_gethostbyname2_context (struct resolv_context *ctx, |
438 | const char *name, int af) |
439 | { |
440 | union |
441 | { |
442 | querybuf *buf; |
443 | u_char *ptr; |
444 | } buf; |
445 | querybuf *origbuf; |
446 | const char *cp; |
447 | char *bp; |
448 | int n, size, type, len; |
449 | struct hostent *ret; |
450 | |
451 | switch (af) { |
452 | case AF_INET: |
453 | size = INADDRSZ; |
454 | type = T_A; |
455 | break; |
456 | case AF_INET6: |
457 | size = IN6ADDRSZ; |
458 | type = T_AAAA; |
459 | break; |
460 | default: |
461 | __set_h_errno (NETDB_INTERNAL); |
462 | __set_errno (EAFNOSUPPORT); |
463 | return (NULL); |
464 | } |
465 | |
466 | host.h_addrtype = af; |
467 | host.h_length = size; |
468 | |
469 | /* |
470 | * if there aren't any dots, it could be a user-level alias. |
471 | * this is also done in res_query() since we are not the only |
472 | * function that looks up host names. |
473 | */ |
474 | char abuf[MAXDNAME]; |
475 | if (strchr (name, '.') != NULL |
476 | && (cp = __res_context_hostalias (ctx, name, abuf, sizeof (abuf)))) |
477 | name = cp; |
478 | |
479 | /* |
480 | * disallow names consisting only of digits/dots, unless |
481 | * they end in a dot. |
482 | */ |
483 | if (isdigit(name[0])) |
484 | for (cp = name;; ++cp) { |
485 | if (!*cp) { |
486 | if (*--cp == '.') |
487 | break; |
488 | /* |
489 | * All-numeric, no dot at the end. |
490 | * Fake up a hostent as if we'd actually |
491 | * done a lookup. |
492 | */ |
493 | if (inet_pton(af, name, host_addr) <= 0) { |
494 | __set_h_errno (HOST_NOT_FOUND); |
495 | return (NULL); |
496 | } |
497 | strncpy(hostbuf, name, MAXDNAME); |
498 | hostbuf[MAXDNAME] = '\0'; |
499 | bp = hostbuf + MAXDNAME; |
500 | len = sizeof hostbuf - MAXDNAME; |
501 | host.h_name = hostbuf; |
502 | host.h_aliases = host_aliases; |
503 | host_aliases[0] = NULL; |
504 | h_addr_ptrs[0] = (char *)host_addr; |
505 | h_addr_ptrs[1] = NULL; |
506 | host.h_addr_list = h_addr_ptrs; |
507 | if (res_use_inet6 ()) |
508 | map_v4v6_hostent(&host, &bp, &len); |
509 | __set_h_errno (NETDB_SUCCESS); |
510 | return (&host); |
511 | } |
512 | if (!isdigit(*cp) && *cp != '.') |
513 | break; |
514 | } |
515 | if ((isxdigit(name[0]) && strchr(name, ':') != NULL) || |
516 | name[0] == ':') |
517 | for (cp = name;; ++cp) { |
518 | if (!*cp) { |
519 | if (*--cp == '.') |
520 | break; |
521 | /* |
522 | * All-IPv6-legal, no dot at the end. |
523 | * Fake up a hostent as if we'd actually |
524 | * done a lookup. |
525 | */ |
526 | if (inet_pton(af, name, host_addr) <= 0) { |
527 | __set_h_errno (HOST_NOT_FOUND); |
528 | return (NULL); |
529 | } |
530 | strncpy(hostbuf, name, MAXDNAME); |
531 | hostbuf[MAXDNAME] = '\0'; |
532 | bp = hostbuf + MAXDNAME; |
533 | len = sizeof hostbuf - MAXDNAME; |
534 | host.h_name = hostbuf; |
535 | host.h_aliases = host_aliases; |
536 | host_aliases[0] = NULL; |
537 | h_addr_ptrs[0] = (char *)host_addr; |
538 | h_addr_ptrs[1] = NULL; |
539 | host.h_addr_list = h_addr_ptrs; |
540 | __set_h_errno (NETDB_SUCCESS); |
541 | return (&host); |
542 | } |
543 | if (!isxdigit(*cp) && *cp != ':' && *cp != '.') |
544 | break; |
545 | } |
546 | |
547 | buf.buf = origbuf = (querybuf *) alloca (1024); |
548 | |
549 | if ((n = __res_context_search |
550 | (ctx, name, C_IN, type, buf.buf->buf, 1024, |
551 | &buf.ptr, NULL, NULL, NULL, NULL)) < 0) { |
552 | if (buf.buf != origbuf) |
553 | free (buf.buf); |
554 | if (errno == ECONNREFUSED) |
555 | return (_gethtbyname2(name, af)); |
556 | return (NULL); |
557 | } |
558 | ret = getanswer(buf.buf, n, name, type); |
559 | if (buf.buf != origbuf) |
560 | free (buf.buf); |
561 | return ret; |
562 | } |
563 | |
564 | struct hostent * |
565 | res_gethostbyname2 (const char *name, int af) |
566 | { |
567 | struct resolv_context *ctx = __resolv_context_get (); |
568 | if (ctx == NULL) |
569 | { |
570 | __set_h_errno (NETDB_INTERNAL); |
571 | return NULL; |
572 | } |
573 | struct hostent *hp = res_gethostbyname2_context (ctx, name, AF_INET); |
574 | __resolv_context_put (ctx); |
575 | return hp; |
576 | } |
577 | libresolv_hidden_def (res_gethostbyname2) |
578 | compat_symbol (libresolv, res_gethostbyname2, res_gethostbyname2, GLIBC_2_0); |
579 | |
580 | static struct hostent * |
581 | res_gethostbyaddr_context (struct resolv_context *ctx, |
582 | const void *addr, socklen_t len, int af) |
583 | { |
584 | const u_char *uaddr = (const u_char *)addr; |
585 | static const u_char mapped[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0xff,0xff }; |
586 | static const u_char tunnelled[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0,0 }; |
587 | int n; |
588 | socklen_t size; |
589 | union |
590 | { |
591 | querybuf *buf; |
592 | u_char *ptr; |
593 | } buf; |
594 | querybuf *orig_buf; |
595 | struct hostent *hp; |
596 | char qbuf[MAXDNAME+1], *qp = NULL; |
597 | |
598 | if (af == AF_INET6 && len == IN6ADDRSZ && |
599 | (!memcmp(uaddr, mapped, sizeof mapped) || |
600 | !memcmp(uaddr, tunnelled, sizeof tunnelled))) { |
601 | /* Unmap. */ |
602 | addr += sizeof mapped; |
603 | uaddr += sizeof mapped; |
604 | af = AF_INET; |
605 | len = INADDRSZ; |
606 | } |
607 | switch (af) { |
608 | case AF_INET: |
609 | size = INADDRSZ; |
610 | break; |
611 | case AF_INET6: |
612 | size = IN6ADDRSZ; |
613 | break; |
614 | default: |
615 | __set_errno (EAFNOSUPPORT); |
616 | __set_h_errno (NETDB_INTERNAL); |
617 | return (NULL); |
618 | } |
619 | if (size != len) { |
620 | __set_errno (EINVAL); |
621 | __set_h_errno (NETDB_INTERNAL); |
622 | return (NULL); |
623 | } |
624 | switch (af) { |
625 | case AF_INET: |
626 | (void) sprintf(qbuf, "%u.%u.%u.%u.in-addr.arpa" , |
627 | (uaddr[3] & 0xff), |
628 | (uaddr[2] & 0xff), |
629 | (uaddr[1] & 0xff), |
630 | (uaddr[0] & 0xff)); |
631 | break; |
632 | case AF_INET6: |
633 | qp = qbuf; |
634 | for (n = IN6ADDRSZ - 1; n >= 0; n--) { |
635 | qp += sprintf(qp, "%x.%x." , |
636 | uaddr[n] & 0xf, |
637 | (uaddr[n] >> 4) & 0xf); |
638 | } |
639 | strcpy(qp, "ip6.arpa" ); |
640 | break; |
641 | default: |
642 | abort(); |
643 | } |
644 | |
645 | buf.buf = orig_buf = (querybuf *) alloca (1024); |
646 | |
647 | n = __res_context_query (ctx, qbuf, C_IN, T_PTR, buf.buf->buf, 1024, |
648 | &buf.ptr, NULL, NULL, NULL, NULL); |
649 | if (n < 0) { |
650 | if (buf.buf != orig_buf) |
651 | free (buf.buf); |
652 | if (errno == ECONNREFUSED) |
653 | return (_gethtbyaddr(addr, len, af)); |
654 | return (NULL); |
655 | } |
656 | hp = getanswer(buf.buf, n, qbuf, T_PTR); |
657 | if (buf.buf != orig_buf) |
658 | free (buf.buf); |
659 | if (!hp) |
660 | return (NULL); /* h_errno was set by getanswer() */ |
661 | hp->h_addrtype = af; |
662 | hp->h_length = len; |
663 | memmove(host_addr, addr, len); |
664 | h_addr_ptrs[0] = (char *)host_addr; |
665 | h_addr_ptrs[1] = NULL; |
666 | if (af == AF_INET && res_use_inet6 ()) { |
667 | map_v4v6_address((char*)host_addr, (char*)host_addr); |
668 | hp->h_addrtype = AF_INET6; |
669 | hp->h_length = IN6ADDRSZ; |
670 | } |
671 | __set_h_errno (NETDB_SUCCESS); |
672 | return (hp); |
673 | } |
674 | |
675 | struct hostent * |
676 | res_gethostbyaddr (const void *addr, socklen_t len, int af) |
677 | { |
678 | struct resolv_context *ctx = __resolv_context_get (); |
679 | if (ctx == NULL) |
680 | { |
681 | __set_h_errno (NETDB_INTERNAL); |
682 | return NULL; |
683 | } |
684 | struct hostent *hp = res_gethostbyaddr_context (ctx, addr, len, af); |
685 | __resolv_context_put (ctx); |
686 | return hp; |
687 | } |
688 | compat_symbol (libresolv, res_gethostbyaddr, res_gethostbyaddr, GLIBC_2_0); |
689 | |
690 | void |
691 | _sethtent (int f) |
692 | { |
693 | if (!hostf) |
694 | hostf = fopen(_PATH_HOSTS, "rce" ); |
695 | else |
696 | rewind(hostf); |
697 | stayopen = f; |
698 | } |
699 | libresolv_hidden_def (_sethtent) |
700 | compat_symbol (libresolv, _sethtent, _sethtent, GLIBC_2_0); |
701 | |
702 | static void |
703 | _endhtent (void) |
704 | { |
705 | if (hostf && !stayopen) { |
706 | (void) fclose(hostf); |
707 | hostf = NULL; |
708 | } |
709 | } |
710 | |
711 | struct hostent * |
712 | _gethtent (void) |
713 | { |
714 | char *p; |
715 | char *cp, **q; |
716 | int af, len; |
717 | |
718 | if (!hostf && !(hostf = fopen(_PATH_HOSTS, "rce" ))) { |
719 | __set_h_errno (NETDB_INTERNAL); |
720 | return (NULL); |
721 | } |
722 | again: |
723 | if (!(p = fgets(hostbuf, sizeof hostbuf, hostf))) { |
724 | __set_h_errno (HOST_NOT_FOUND); |
725 | return (NULL); |
726 | } |
727 | if (*p == '#') |
728 | goto again; |
729 | if (!(cp = strpbrk(p, "#\n" ))) |
730 | goto again; |
731 | *cp = '\0'; |
732 | if (!(cp = strpbrk(p, " \t" ))) |
733 | goto again; |
734 | *cp++ = '\0'; |
735 | if (inet_pton(AF_INET6, p, host_addr) > 0) { |
736 | af = AF_INET6; |
737 | len = IN6ADDRSZ; |
738 | } else if (inet_pton(AF_INET, p, host_addr) > 0) { |
739 | if (res_use_inet6 ()) { |
740 | map_v4v6_address((char*)host_addr, (char*)host_addr); |
741 | af = AF_INET6; |
742 | len = IN6ADDRSZ; |
743 | } else { |
744 | af = AF_INET; |
745 | len = INADDRSZ; |
746 | } |
747 | } else { |
748 | goto again; |
749 | } |
750 | h_addr_ptrs[0] = (char *)host_addr; |
751 | h_addr_ptrs[1] = NULL; |
752 | host.h_addr_list = h_addr_ptrs; |
753 | host.h_length = len; |
754 | host.h_addrtype = af; |
755 | while (*cp == ' ' || *cp == '\t') |
756 | cp++; |
757 | host.h_name = cp; |
758 | q = host.h_aliases = host_aliases; |
759 | if ((cp = strpbrk(cp, " \t" ))) |
760 | *cp++ = '\0'; |
761 | while (cp && *cp) { |
762 | if (*cp == ' ' || *cp == '\t') { |
763 | cp++; |
764 | continue; |
765 | } |
766 | if (q < &host_aliases[MAXALIASES - 1]) |
767 | *q++ = cp; |
768 | if ((cp = strpbrk(cp, " \t" ))) |
769 | *cp++ = '\0'; |
770 | } |
771 | *q = NULL; |
772 | __set_h_errno (NETDB_SUCCESS); |
773 | return (&host); |
774 | } |
775 | libresolv_hidden_def (_gethtent) |
776 | compat_symbol (libresolv, _gethtent, _gethtent, GLIBC_2_0); |
777 | |
778 | struct hostent * |
779 | _gethtbyname (const char *name) |
780 | { |
781 | struct hostent *hp; |
782 | |
783 | if (res_use_inet6 ()) { |
784 | hp = _gethtbyname2(name, AF_INET6); |
785 | if (hp) |
786 | return (hp); |
787 | } |
788 | return (_gethtbyname2(name, AF_INET)); |
789 | } |
790 | compat_symbol (libresolv, _gethtbyname, _gethtbyname, GLIBC_2_0); |
791 | |
792 | struct hostent * |
793 | _gethtbyname2 (const char *name, int af) |
794 | { |
795 | struct hostent *p; |
796 | char **cp; |
797 | |
798 | _sethtent(0); |
799 | while ((p = _gethtent())) { |
800 | if (p->h_addrtype != af) |
801 | continue; |
802 | if (strcasecmp(p->h_name, name) == 0) |
803 | break; |
804 | for (cp = p->h_aliases; *cp != 0; cp++) |
805 | if (strcasecmp(*cp, name) == 0) |
806 | goto found; |
807 | } |
808 | found: |
809 | _endhtent(); |
810 | return (p); |
811 | } |
812 | libresolv_hidden_def (_gethtbyname2) |
813 | compat_symbol (libresolv, _gethtbyname2, _gethtbyname2, GLIBC_2_0); |
814 | |
815 | struct hostent * |
816 | _gethtbyaddr (const char *addr, size_t len, int af) |
817 | { |
818 | struct hostent *p; |
819 | |
820 | _sethtent(0); |
821 | while ((p = _gethtent())) |
822 | if (p->h_addrtype == af && !memcmp(p->h_addr, addr, len)) |
823 | break; |
824 | _endhtent(); |
825 | return (p); |
826 | } |
827 | libresolv_hidden_def (_gethtbyaddr) |
828 | compat_symbol (libresolv, _gethtbyaddr, _gethtbyaddr, GLIBC_2_0); |
829 | |
830 | static void |
831 | map_v4v6_address (const char *src, char *dst) |
832 | { |
833 | u_char *p = (u_char *)dst; |
834 | char tmp[INADDRSZ]; |
835 | int i; |
836 | |
837 | /* Stash a temporary copy so our caller can update in place. */ |
838 | memcpy(tmp, src, INADDRSZ); |
839 | /* Mark this ipv6 addr as a mapped ipv4. */ |
840 | for (i = 0; i < 10; i++) |
841 | *p++ = 0x00; |
842 | *p++ = 0xff; |
843 | *p++ = 0xff; |
844 | /* Retrieve the saved copy and we're done. */ |
845 | memcpy((void*)p, tmp, INADDRSZ); |
846 | } |
847 | |
848 | static void |
849 | map_v4v6_hostent (struct hostent *hp, char **bpp, int *lenp) |
850 | { |
851 | char **ap; |
852 | |
853 | if (hp->h_addrtype != AF_INET || hp->h_length != INADDRSZ) |
854 | return; |
855 | hp->h_addrtype = AF_INET6; |
856 | hp->h_length = IN6ADDRSZ; |
857 | for (ap = hp->h_addr_list; *ap; ap++) { |
858 | int i = sizeof(align) - ((u_long)*bpp % sizeof(align)); |
859 | |
860 | if (*lenp < (i + IN6ADDRSZ)) { |
861 | /* Out of memory. Truncate address list here. XXX */ |
862 | *ap = NULL; |
863 | return; |
864 | } |
865 | *bpp += i; |
866 | *lenp -= i; |
867 | map_v4v6_address(*ap, *bpp); |
868 | *ap = *bpp; |
869 | *bpp += IN6ADDRSZ; |
870 | *lenp -= IN6ADDRSZ; |
871 | } |
872 | } |
873 | |
874 | extern void |
875 | addrsort (char **ap, int num) |
876 | { |
877 | int i, j; |
878 | char **p; |
879 | short aval[MAXADDRS]; |
880 | int needsort = 0; |
881 | |
882 | p = ap; |
883 | for (i = 0; i < num; i++, p++) { |
884 | for (j = 0 ; (unsigned)j < _res.nsort; j++) |
885 | if (_res.sort_list[j].addr.s_addr == |
886 | (((struct in_addr *)(*p))->s_addr & _res.sort_list[j].mask)) |
887 | break; |
888 | aval[i] = j; |
889 | if (needsort == 0 && i > 0 && j < aval[i-1]) |
890 | needsort = i; |
891 | } |
892 | if (!needsort) |
893 | return; |
894 | |
895 | while (needsort < num) { |
896 | for (j = needsort - 1; j >= 0; j--) { |
897 | if (aval[j] > aval[j+1]) { |
898 | char *hp; |
899 | |
900 | i = aval[j]; |
901 | aval[j] = aval[j+1]; |
902 | aval[j+1] = i; |
903 | |
904 | hp = ap[j]; |
905 | ap[j] = ap[j+1]; |
906 | ap[j+1] = hp; |
907 | |
908 | } else |
909 | break; |
910 | } |
911 | needsort++; |
912 | } |
913 | } |
914 | |
915 | #endif /* SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_25) */ |
916 | |