?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
Updated to fedora-glibc-20060511T1325
[glibc.git] / sysdeps / posix / getaddrinfo.c
bloba78c670bfbd9804143f1be71bb16b827a01dfb74
1 /* The Inner Net License, Version 2.00
2
3 The author(s) grant permission for redistribution and use in source and
4 binary forms, with or without modification, of the software and documentation
5 provided that the following conditions are met:
6
7 0. If you receive a version of the software that is specifically labelled
8 as not being for redistribution (check the version message and/or README),
9 you are not permitted to redistribute that version of the software in any
10 way or form.
11 1. All terms of the all other applicable copyrights and licenses must be
12 followed.
13 2. Redistributions of source code must retain the authors' copyright
14 notice(s), this list of conditions, and the following disclaimer.
15 3. Redistributions in binary form must reproduce the authors' copyright
16 notice(s), this list of conditions, and the following disclaimer in the
17 documentation and/or other materials provided with the distribution.
18 4. [The copyright holder has authorized the removal of this clause.]
19 5. Neither the name(s) of the author(s) nor the names of its contributors
20 may be used to endorse or promote products derived from this software
21 without specific prior written permission.
22
23 THIS SOFTWARE IS PROVIDED BY ITS AUTHORS AND CONTRIBUTORS ``AS IS'' AND ANY
24 EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
25 WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
26 DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE FOR ANY
27 DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
28 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
29 LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
30 ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
32 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33
34 If these license terms cause you a real problem, contact the author. */
35
36 /* This software is Copyright 1996 by Craig Metz, All Rights Reserved. */
37
38 #include <assert.h>
39 #include <ctype.h>
40 #include <errno.h>
41 #include <ifaddrs.h>
42 #include <netdb.h>
43 #include <resolv.h>
44 #include <stdbool.h>
45 #include <stdio.h>
46 #include <stdio_ext.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <arpa/inet.h>
50 #include <net/if.h>
51 #include <netinet/in.h>
52 #include <sys/socket.h>
53 #include <sys/stat.h>
54 #include <sys/types.h>
55 #include <sys/un.h>
56 #include <sys/utsname.h>
57 #include <unistd.h>
58 #include <nsswitch.h>
59 #include <bits/libc-lock.h>
60 #include <not-cancel.h>
61 #include <nscd/nscd-client.h>
62 #include <nscd/nscd_proto.h>
63
64 #ifdef HAVE_LIBIDN
65 extern int __idna_to_ascii_lz (const char *input, char **output, int flags);
66 extern int __idna_to_unicode_lzlz (const char *input, char **output,
67 int flags);
68 # include <libidn/idna.h>
69 #endif
70
71 #define GAIH_OKIFUNSPEC 0x0100
72 #define GAIH_EAI ~(GAIH_OKIFUNSPEC)
73
74 #ifndef UNIX_PATH_MAX
75 # define UNIX_PATH_MAX 108
76 #endif
77
78 struct gaih_service
79 {
80 const char *name;
81 int num;
82 };
83
84 struct gaih_servtuple
85 {
86 struct gaih_servtuple *next;
87 int socktype;
88 int protocol;
89 int port;
90 };
91
92 static const struct gaih_servtuple nullserv;
93
94 struct gaih_addrtuple
95 {
96 struct gaih_addrtuple *next;
97 char *name;
98 int family;
99 uint32_t addr[4];
100 uint32_t scopeid;
101 };
102
103 struct gaih_typeproto
104 {
105 int socktype;
106 int protocol;
107 char name[4];
108 int protoflag;
109 };
110
111 /* Values for `protoflag'. */
112 #define GAI_PROTO_NOSERVICE 1
113 #define GAI_PROTO_PROTOANY 2
114
115 static const struct gaih_typeproto gaih_inet_typeproto[] =
116 {
117 { 0, 0, "", 0 },
118 { SOCK_STREAM, IPPROTO_TCP, "tcp", 0 },
119 { SOCK_DGRAM, IPPROTO_UDP, "udp", 0 },
120 { SOCK_RAW, 0, "raw", GAI_PROTO_PROTOANY|GAI_PROTO_NOSERVICE },
121 { 0, 0, "", 0 }
122 };
123
124 struct gaih
125 {
126 int family;
127 int (*gaih)(const char *name, const struct gaih_service *service,
128 const struct addrinfo *req, struct addrinfo **pai,
129 unsigned int *naddrs);
130 };
131
132 static const struct addrinfo default_hints =
133 {
134 .ai_flags = AI_DEFAULT,
135 .ai_family = PF_UNSPEC,
136 .ai_socktype = 0,
137 .ai_protocol = 0,
138 .ai_addrlen = 0,
139 .ai_addr = NULL,
140 .ai_canonname = NULL,
141 .ai_next = NULL
142 };
143
144
145 #if 0
146 /* Using Unix sockets this way is a security risk. */
147 static int
148 gaih_local (const char *name, const struct gaih_service *service,
149 const struct addrinfo *req, struct addrinfo **pai)
150 {
151 struct utsname utsname;
152
153 if ((name != NULL) && (req->ai_flags & AI_NUMERICHOST))
154 return GAIH_OKIFUNSPEC | -EAI_NONAME;
155
156 if ((name != NULL) || (req->ai_flags & AI_CANONNAME))
157 if (uname (&utsname) < 0)
158 return -EAI_SYSTEM;
159
160 if (name != NULL)
161 {
162 if (strcmp(name, "localhost") &&
163 strcmp(name, "local") &&
164 strcmp(name, "unix") &&
165 strcmp(name, utsname.nodename))
166 return GAIH_OKIFUNSPEC | -EAI_NONAME;
167 }
168
169 if (req->ai_protocol || req->ai_socktype)
170 {
171 const struct gaih_typeproto *tp = gaih_inet_typeproto + 1;
172
173 while (tp->name[0]
174 && ((tp->protoflag & GAI_PROTO_NOSERVICE) != 0
175 || (req->ai_socktype != 0 && req->ai_socktype != tp->socktype)
176 || (req->ai_protocol != 0
177 && !(tp->protoflag & GAI_PROTO_PROTOANY)
178 && req->ai_protocol != tp->protocol)))
179 ++tp;
180
181 if (! tp->name[0])
182 {
183 if (req->ai_socktype)
184 return GAIH_OKIFUNSPEC | -EAI_SOCKTYPE;
185 else
186 return GAIH_OKIFUNSPEC | -EAI_SERVICE;
187 }
188 }
189
190 *pai = malloc (sizeof (struct addrinfo) + sizeof (struct sockaddr_un)
191 + ((req->ai_flags & AI_CANONNAME)
192 ? (strlen(utsname.nodename) + 1): 0));
193 if (*pai == NULL)
194 return -EAI_MEMORY;
195
196 (*pai)->ai_next = NULL;
197 (*pai)->ai_flags = req->ai_flags;
198 (*pai)->ai_family = AF_LOCAL;
199 (*pai)->ai_socktype = req->ai_socktype ? req->ai_socktype : SOCK_STREAM;
200 (*pai)->ai_protocol = req->ai_protocol;
201 (*pai)->ai_addrlen = sizeof (struct sockaddr_un);
202 (*pai)->ai_addr = (void *) (*pai) + sizeof (struct addrinfo);
203
204 #ifdef _HAVE_SA_LEN
205 ((struct sockaddr_un *) (*pai)->ai_addr)->sun_len =
206 sizeof (struct sockaddr_un);
207 #endif /* _HAVE_SA_LEN */
208
209 ((struct sockaddr_un *)(*pai)->ai_addr)->sun_family = AF_LOCAL;
210 memset(((struct sockaddr_un *)(*pai)->ai_addr)->sun_path, 0, UNIX_PATH_MAX);
211
212 if (service)
213 {
214 struct sockaddr_un *sunp = (struct sockaddr_un *) (*pai)->ai_addr;
215
216 if (strchr (service->name, '/') != NULL)
217 {
218 if (strlen (service->name) >= sizeof (sunp->sun_path))
219 return GAIH_OKIFUNSPEC | -EAI_SERVICE;
220
221 strcpy (sunp->sun_path, service->name);
222 }
223 else
224 {
225 if (strlen (P_tmpdir "/") + 1 + strlen (service->name) >=
226 sizeof (sunp->sun_path))
227 return GAIH_OKIFUNSPEC | -EAI_SERVICE;
228
229 __stpcpy (__stpcpy (sunp->sun_path, P_tmpdir "/"), service->name);
230 }
231 }
232 else
233 {
234 /* This is a dangerous use of the interface since there is a time
235 window between the test for the file and the actual creation
236 (done by the caller) in which a file with the same name could
237 be created. */
238 char *buf = ((struct sockaddr_un *) (*pai)->ai_addr)->sun_path;
239
240 if (__builtin_expect (__path_search (buf, L_tmpnam, NULL, NULL, 0),
241 0) != 0
242 || __builtin_expect (__gen_tempname (buf, __GT_NOCREATE), 0) != 0)
243 return -EAI_SYSTEM;
244 }
245
246 if (req->ai_flags & AI_CANONNAME)
247 (*pai)->ai_canonname = strcpy ((char *) *pai + sizeof (struct addrinfo)
248 + sizeof (struct sockaddr_un),
249 utsname.nodename);
250 else
251 (*pai)->ai_canonname = NULL;
252 return 0;
253 }
254 #endif /* 0 */
255
256
257 static int
258 gaih_inet_serv (const char *servicename, const struct gaih_typeproto *tp,
259 const struct addrinfo *req, struct gaih_servtuple *st)
260 {
261 struct servent *s;
262 size_t tmpbuflen = 1024;
263 struct servent ts;
264 char *tmpbuf;
265 int r;
266
267 do
268 {
269 tmpbuf = __alloca (tmpbuflen);
270
271 r = __getservbyname_r (servicename, tp->name, &ts, tmpbuf, tmpbuflen,
272 &s);
273 if (r != 0 || s == NULL)
274 {
275 if (r == ERANGE)
276 tmpbuflen *= 2;
277 else
278 return GAIH_OKIFUNSPEC | -EAI_SERVICE;
279 }
280 }
281 while (r);
282
283 st->next = NULL;
284 st->socktype = tp->socktype;
285 st->protocol = ((tp->protoflag & GAI_PROTO_PROTOANY)
286 ? req->ai_protocol : tp->protocol);
287 st->port = s->s_port;
288
289 return 0;
290 }
291
292 #define gethosts(_family, _type) \
293 { \
294 int i; \
295 int herrno; \
296 struct hostent th; \
297 struct hostent *h; \
298 char *localcanon = NULL; \
299 no_data = 0; \
300 while (1) { \
301 rc = 0; \
302 status = DL_CALL_FCT (fct, (name, _family, &th, tmpbuf, tmpbuflen, \
303 &rc, &herrno, NULL, &localcanon)); \
304 if (rc != ERANGE || herrno != NETDB_INTERNAL) \
305 break; \
306 tmpbuf = extend_alloca (tmpbuf, tmpbuflen, 2 * tmpbuflen); \
307 } \
308 if (status == NSS_STATUS_SUCCESS && rc == 0) \
309 h = &th; \
310 else \
311 h = NULL; \
312 if (rc != 0) \
313 { \
314 if (herrno == NETDB_INTERNAL) \
315 { \
316 __set_h_errno (herrno); \
317 return -EAI_SYSTEM; \
318 } \
319 if (herrno == TRY_AGAIN) \
320 no_data = EAI_AGAIN; \
321 else \
322 no_data = herrno == NO_DATA; \
323 } \
324 else if (h != NULL) \
325 { \
326 for (i = 0; h->h_addr_list[i]; i++) \
327 { \
328 if (*pat == NULL) \
329 { \
330 *pat = __alloca (sizeof (struct gaih_addrtuple)); \
331 (*pat)->scopeid = 0; \
332 } \
333 uint32_t *addr = (*pat)->addr; \
334 (*pat)->next = NULL; \
335 (*pat)->name = i == 0 ? strdupa (h->h_name) : NULL; \
336 if (_family == AF_INET && req->ai_family == AF_INET6) \
337 { \
338 (*pat)->family = AF_INET6; \
339 addr[3] = *(uint32_t *) h->h_addr_list[i]; \
340 addr[2] = htonl (0xffff); \
341 addr[1] = 0; \
342 addr[0] = 0; \
343 } \
344 else \
345 { \
346 (*pat)->family = _family; \
347 memcpy (addr, h->h_addr_list[i], sizeof(_type)); \
348 } \
349 pat = &((*pat)->next); \
350 } \
351 \
352 if (localcanon != NULL && canon == NULL) \
353 canon = strdupa (localcanon); \
354 \
355 if (_family == AF_INET6 && i > 0) \
356 got_ipv6 = true; \
357 } \
358 }
359
360
361 typedef enum nss_status (*nss_gethostbyname3_r)
362 (const char *name, int af, struct hostent *host,
363 char *buffer, size_t buflen, int *errnop,
364 int *h_errnop, int32_t *ttlp, char **canonp);
365 typedef enum nss_status (*nss_getcanonname_r)
366 (const char *name, char *buffer, size_t buflen, char **result,
367 int *errnop, int *h_errnop);
368 extern service_user *__nss_hosts_database attribute_hidden;
369
370
371 static int
372 gaih_inet (const char *name, const struct gaih_service *service,
373 const struct addrinfo *req, struct addrinfo **pai,
374 unsigned int *naddrs)
375 {
376 const struct gaih_typeproto *tp = gaih_inet_typeproto;
377 struct gaih_servtuple *st = (struct gaih_servtuple *) &nullserv;
378 struct gaih_addrtuple *at = NULL;
379 int rc;
380 bool got_ipv6 = false;
381 const char *canon = NULL;
382 const char *orig_name = name;
383
384 if (req->ai_protocol || req->ai_socktype)
385 {
386 ++tp;
387
388 while (tp->name[0]
389 && ((req->ai_socktype != 0 && req->ai_socktype != tp->socktype)
390 || (req->ai_protocol != 0
391 && !(tp->protoflag & GAI_PROTO_PROTOANY)
392 && req->ai_protocol != tp->protocol)))
393 ++tp;
394
395 if (! tp->name[0])
396 {
397 if (req->ai_socktype)
398 return GAIH_OKIFUNSPEC | -EAI_SOCKTYPE;
399 else
400 return GAIH_OKIFUNSPEC | -EAI_SERVICE;
401 }
402 }
403
404 int port = 0;
405 if (service != NULL)
406 {
407 if ((tp->protoflag & GAI_PROTO_NOSERVICE) != 0)
408 return GAIH_OKIFUNSPEC | -EAI_SERVICE;
409
410 if (service->num < 0)
411 {
412 if (tp->name[0])
413 {
414 st = (struct gaih_servtuple *)
415 __alloca (sizeof (struct gaih_servtuple));
416
417 if ((rc = gaih_inet_serv (service->name, tp, req, st)))
418 return rc;
419 }
420 else
421 {
422 struct gaih_servtuple **pst = &st;
423 for (tp++; tp->name[0]; tp++)
424 {
425 struct gaih_servtuple *newp;
426
427 if ((tp->protoflag & GAI_PROTO_NOSERVICE) != 0)
428 continue;
429
430 if (req->ai_socktype != 0
431 && req->ai_socktype != tp->socktype)
432 continue;
433 if (req->ai_protocol != 0
434 && !(tp->protoflag & GAI_PROTO_PROTOANY)
435 && req->ai_protocol != tp->protocol)
436 continue;
437
438 newp = (struct gaih_servtuple *)
439 __alloca (sizeof (struct gaih_servtuple));
440
441 if ((rc = gaih_inet_serv (service->name, tp, req, newp)))
442 {
443 if (rc & GAIH_OKIFUNSPEC)
444 continue;
445 return rc;
446 }
447
448 *pst = newp;
449 pst = &(newp->next);
450 }
451 if (st == (struct gaih_servtuple *) &nullserv)
452 return GAIH_OKIFUNSPEC | -EAI_SERVICE;
453 }
454 }
455 else
456 {
457 port = htons (service->num);
458 goto got_port;
459 }
460 }
461 else
462 {
463 got_port:
464
465 if (req->ai_socktype || req->ai_protocol)
466 {
467 st = __alloca (sizeof (struct gaih_servtuple));
468 st->next = NULL;
469 st->socktype = tp->socktype;
470 st->protocol = ((tp->protoflag & GAI_PROTO_PROTOANY)
471 ? req->ai_protocol : tp->protocol);
472 st->port = port;
473 }
474 else
475 {
476 /* Neither socket type nor protocol is set. Return all socket types
477 we know about. */
478 struct gaih_servtuple **lastp = &st;
479 for (++tp; tp->name[0]; ++tp)
480 {
481 struct gaih_servtuple *newp;
482
483 newp = __alloca (sizeof (struct gaih_servtuple));
484 newp->next = NULL;
485 newp->socktype = tp->socktype;
486 newp->protocol = tp->protocol;
487 newp->port = port;
488
489 *lastp = newp;
490 lastp = &newp->next;
491 }
492 }
493 }
494
495 if (name != NULL)
496 {
497 at = __alloca (sizeof (struct gaih_addrtuple));
498
499 at->family = AF_UNSPEC;
500 at->scopeid = 0;
501 at->next = NULL;
502
503 #ifdef HAVE_LIBIDN
504 if (req->ai_flags & AI_IDN)
505 {
506 int idn_flags = 0;
507 if (req->ai_flags & AI_IDN_ALLOW_UNASSIGNED)
508 idn_flags |= IDNA_ALLOW_UNASSIGNED;
509 if (req->ai_flags & AI_IDN_USE_STD3_ASCII_RULES)
510 idn_flags |= IDNA_USE_STD3_ASCII_RULES;
511
512 char *p = NULL;
513 rc = __idna_to_ascii_lz (name, &p, idn_flags);
514 if (rc != IDNA_SUCCESS)
515 {
516 if (rc == IDNA_MALLOC_ERROR)
517 return -EAI_MEMORY;
518 if (rc == IDNA_DLOPEN_ERROR)
519 return -EAI_SYSTEM;
520 return -EAI_IDN_ENCODE;
521 }
522 /* In case the output string is the same as the input string
523 no new string has been allocated. */
524 if (p != name)
525 {
526 name = strdupa (p);
527 free (p);
528 }
529 }
530 #endif
531
532 if (__inet_aton (name, (struct in_addr *) at->addr) != 0)
533 {
534 if (req->ai_family == AF_UNSPEC || req->ai_family == AF_INET)
535 at->family = AF_INET;
536 else if (req->ai_family == AF_INET6 && (req->ai_flags & AI_V4MAPPED))
537 {
538 at->addr[3] = at->addr[0];
539 at->addr[2] = htonl (0xffff);
540 at->addr[1] = 0;
541 at->addr[0] = 0;
542 at->family = AF_INET6;
543 }
544 else
545 return -EAI_ADDRFAMILY;
546
547 if (req->ai_flags & AI_CANONNAME)
548 canon = name;
549 }
550 else if (at->family == AF_UNSPEC)
551 {
552 char *namebuf = (char *) name;
553 char *scope_delim = strchr (name, SCOPE_DELIMITER);
554
555 if (__builtin_expect (scope_delim != NULL, 0))
556 {
557 namebuf = alloca (scope_delim - name + 1);
558 *((char *) __mempcpy (namebuf, name, scope_delim - name)) = '\0';
559 }
560
561 if (inet_pton (AF_INET6, namebuf, at->addr) > 0)
562 {
563 if (req->ai_family == AF_UNSPEC || req->ai_family == AF_INET6)
564 at->family = AF_INET6;
565 else if (req->ai_family == AF_INET
566 && IN6_IS_ADDR_V4MAPPED (at->addr))
567 {
568 at->addr[0] = at->addr[3];
569 at->family = AF_INET;
570 }
571 else
572 return -EAI_ADDRFAMILY;
573
574 if (scope_delim != NULL)
575 {
576 int try_numericscope = 0;
577 if (IN6_IS_ADDR_LINKLOCAL (at->addr)
578 || IN6_IS_ADDR_MC_LINKLOCAL (at->addr))
579 {
580 at->scopeid = if_nametoindex (scope_delim + 1);
581 if (at->scopeid == 0)
582 try_numericscope = 1;
583 }
584 else
585 try_numericscope = 1;
586
587 if (try_numericscope != 0)
588 {
589 char *end;
590 assert (sizeof (uint32_t) <= sizeof (unsigned long));
591 at->scopeid = (uint32_t) strtoul (scope_delim + 1, &end,
592 10);
593 if (*end != '\0')
594 return GAIH_OKIFUNSPEC | -EAI_NONAME;
595 }
596 }
597
598 if (req->ai_flags & AI_CANONNAME)
599 canon = name;
600 }
601 }
602
603 if (at->family == AF_UNSPEC && (req->ai_flags & AI_NUMERICHOST) == 0)
604 {
605 struct gaih_addrtuple **pat = &at;
606 int no_data = 0;
607 int no_inet6_data = 0;
608 service_user *nip = NULL;
609 enum nss_status inet6_status = NSS_STATUS_UNAVAIL;
610 enum nss_status status = NSS_STATUS_UNAVAIL;
611 int no_more;
612 int old_res_options;
613
614 /* If we do not have to look for IPv4 and IPv6 together, use
615 the simple, old functions. */
616 if (req->ai_family == AF_INET
617 || (req->ai_family == AF_INET6
618 && ((req->ai_flags & AI_V4MAPPED) == 0
619 || (req->ai_flags & AI_ALL) == 0)))
620 {
621 int family = req->ai_family;
622 size_t tmpbuflen = 512;
623 char *tmpbuf = alloca (tmpbuflen);
624 int rc;
625 struct hostent th;
626 struct hostent *h;
627 int herrno;
628
629 simple_again:
630 while (1)
631 {
632 rc = __gethostbyname2_r (name, family, &th, tmpbuf,
633 tmpbuflen, &h, &herrno);
634 if (rc != ERANGE || herrno != NETDB_INTERNAL)
635 break;
636 tmpbuf = extend_alloca (tmpbuf, tmpbuflen, 2 * tmpbuflen);
637 }
638
639 if (rc == 0)
640 {
641 if (h == NULL)
642 {
643 if (req->ai_family == AF_INET6
644 && (req->ai_flags & AI_V4MAPPED)
645 && family == AF_INET6)
646 {
647 /* Try again, this time looking for IPv4
648 addresses. */
649 family = AF_INET;
650 goto simple_again;
651 }
652 }
653 else
654 {
655 /* We found data, now convert it into the list. */
656 for (int i = 0; h->h_addr_list[i]; ++i)
657 {
658 if (*pat == NULL)
659 {
660 *pat = __alloca (sizeof (struct gaih_addrtuple));
661 (*pat)->scopeid = 0;
662 }
663 (*pat)->next = NULL;
664 (*pat)->family = req->ai_family;
665 if (family == req->ai_family)
666 memcpy ((*pat)->addr, h->h_addr_list[i],
667 h->h_length);
668 else
669 {
670 uint32_t *addr = (uint32_t *) (*pat)->addr;
671 addr[3] = *(uint32_t *) h->h_addr_list[i];
672 addr[2] = htonl (0xffff);
673 addr[1] = 0;
674 addr[0] = 0;
675 }
676 pat = &((*pat)->next);
677 }
678 }
679 }
680 else
681 {
682 if (herrno == NETDB_INTERNAL)
683 {
684 __set_h_errno (herrno);
685 return -EAI_SYSTEM;
686 }
687 if (herrno == TRY_AGAIN)
688 {
689 return -EAI_AGAIN;
690 }
691 /* We made requests but they turned out no data.
692 The name is known, though. */
693 return GAIH_OKIFUNSPEC | -EAI_NODATA;
694 }
695
696 goto process_list;
697 }
698
699 #ifdef USE_NSCD
700 if (__nss_not_use_nscd_hosts > 0
701 && ++__nss_not_use_nscd_hosts > NSS_NSCD_RETRY)
702 __nss_not_use_nscd_hosts = 0;
703
704 if (!__nss_not_use_nscd_hosts)
705 {
706 /* Try to use nscd. */
707 struct nscd_ai_result *air = NULL;
708 int herrno;
709 int err = __nscd_getai (name, &air, &herrno);
710 if (air != NULL)
711 {
712 /* Transform into gaih_addrtuple list. */
713 bool added_canon = (req->ai_flags & AI_CANONNAME) == 0;
714 char *addrs = air->addrs;
715
716 for (int i = 0; i < air->naddrs; ++i)
717 {
718 socklen_t size = (air->family[i] == AF_INET
719 ? INADDRSZ : IN6ADDRSZ);
720 if (*pat == NULL)
721 {
722 *pat = __alloca (sizeof (struct gaih_addrtuple));
723 (*pat)->scopeid = 0;
724 }
725 uint32_t *pataddr = (*pat)->addr;
726 (*pat)->next = NULL;
727 if (added_canon || air->canon == NULL)
728 (*pat)->name = NULL;
729 else
730 canon = (*pat)->name = strdupa (air->canon);
731
732 if (air->family[i] == AF_INET
733 && req->ai_family == AF_INET6
734 && (req->ai_flags & AI_V4MAPPED))
735 {
736 (*pat)->family = AF_INET6;
737 pataddr[3] = *(uint32_t *) addrs;
738 pataddr[2] = htonl (0xffff);
739 pataddr[1] = 0;
740 pataddr[0] = 0;
741 pat = &((*pat)->next);
742 added_canon = true;
743 }
744 else if (req->ai_family == AF_UNSPEC
745 || air->family[i] == req->ai_family)
746 {
747 (*pat)->family = air->family[i];
748 memcpy (pataddr, addrs, size);
749 pat = &((*pat)->next);
750 added_canon = true;
751 if (air->family[i] == AF_INET6)
752 got_ipv6 = true;
753 }
754 addrs += size;
755 }
756
757 free (air);
758
759 if (at->family == AF_UNSPEC)
760 return GAIH_OKIFUNSPEC | -EAI_NONAME;
761
762 goto process_list;
763 }
764 else if (err != 0 && __nss_not_use_nscd_hosts == 0)
765 {
766 if (herrno == NETDB_INTERNAL && errno == ENOMEM)
767 return -EAI_MEMORY;
768 if (herrno == TRY_AGAIN)
769 return -EAI_AGAIN;
770 return -EAI_SYSTEM;
771 }
772 }
773 #endif
774
775 if (__nss_hosts_database != NULL)
776 {
777 no_more = 0;
778 nip = __nss_hosts_database;
779 }
780 else
781 no_more = __nss_database_lookup ("hosts", NULL,
782 "dns [!UNAVAIL=return] files",
783 &nip);
784
785 if (__res_maybe_init (&_res, 0) == -1)
786 no_more = 1;
787
788 /* If we are looking for both IPv4 and IPv6 address we don't
789 want the lookup functions to automatically promote IPv4
790 addresses to IPv6 addresses. Currently this is decided
791 by setting the RES_USE_INET6 bit in _res.options. */
792 old_res_options = _res.options;
793 _res.options &= ~RES_USE_INET6;
794
795 size_t tmpbuflen = 512;
796 char *tmpbuf = alloca (tmpbuflen);
797
798 while (!no_more)
799 {
800 nss_gethostbyname3_r fct = NULL;
801 if (req->ai_flags & AI_CANONNAME)
802 /* No need to use this function if we do not look for
803 the canonical name. The function does not exist in
804 all NSS modules and therefore the lookup would
805 often fail. */
806 fct = __nss_lookup_function (nip, "gethostbyname3_r");
807 if (fct == NULL)
808 /* We are cheating here. The gethostbyname2_r function does
809 not have the same interface as gethostbyname3_r but the
810 extra arguments the latter takes are added at the end.
811 So the gethostbyname2_r code will just ignore them. */
812 fct = __nss_lookup_function (nip, "gethostbyname2_r");
813
814 if (fct != NULL)
815 {
816 if (req->ai_family == AF_INET6
817 || req->ai_family == AF_UNSPEC)
818 {
819 gethosts (AF_INET6, struct in6_addr);
820 no_inet6_data = no_data;
821 inet6_status = status;
822 }
823 if (req->ai_family == AF_INET
824 || req->ai_family == AF_UNSPEC
825 || (req->ai_family == AF_INET6
826 && (req->ai_flags & AI_V4MAPPED)
827 /* Avoid generating the mapped addresses if we
828 know we are not going to need them. */
829 && ((req->ai_flags & AI_ALL) || !got_ipv6)))
830 {
831 gethosts (AF_INET, struct in_addr);
832
833 if (req->ai_family == AF_INET)
834 {
835 no_inet6_data = no_data;
836 inet6_status = status;
837 }
838 }
839
840 /* If we found one address for AF_INET or AF_INET6,
841 don't continue the search. */
842 if (inet6_status == NSS_STATUS_SUCCESS
843 || status == NSS_STATUS_SUCCESS)
844 {
845 if ((req->ai_flags & AI_CANONNAME) != 0 && canon == NULL)
846 {
847 /* If we need the canonical name, get it
848 from the same service as the result. */
849 nss_getcanonname_r cfct;
850 int herrno;
851
852 cfct = __nss_lookup_function (nip, "getcanonname_r");
853 if (cfct != NULL)
854 {
855 const size_t max_fqdn_len = 256;
856 char *buf = alloca (max_fqdn_len);
857 char *s;
858
859 if (DL_CALL_FCT (cfct, (at->name ?: name, buf,
860 max_fqdn_len, &s, &rc,
861 &herrno))
862 == NSS_STATUS_SUCCESS)
863 canon = s;
864 else
865 /* Set to name now to avoid using
866 gethostbyaddr. */
867 canon = name;
868 }
869 }
870
871 break;
872 }
873
874 /* We can have different states for AF_INET and
875 AF_INET6. Try to find a useful one for both. */
876 if (inet6_status == NSS_STATUS_TRYAGAIN)
877 status = NSS_STATUS_TRYAGAIN;
878 else if (status == NSS_STATUS_UNAVAIL
879 && inet6_status != NSS_STATUS_UNAVAIL)
880 status = inet6_status;
881 }
882
883 if (nss_next_action (nip, status) == NSS_ACTION_RETURN)
884 break;
885
886 if (nip->next == NULL)
887 no_more = -1;
888 else
889 nip = nip->next;
890 }
891
892 _res.options = old_res_options;
893
894 if (no_data != 0 && no_inet6_data != 0)
895 {
896 /* If both requests timed out report this. */
897 if (no_data == EAI_AGAIN && no_inet6_data == EAI_AGAIN)
898 return -EAI_AGAIN;
899
900 /* We made requests but they turned out no data. The name
901 is known, though. */
902 return GAIH_OKIFUNSPEC | -EAI_NODATA;
903 }
904 }
905
906 process_list:
907 if (at->family == AF_UNSPEC)
908 return GAIH_OKIFUNSPEC | -EAI_NONAME;
909 }
910 else
911 {
912 struct gaih_addrtuple *atr;
913 atr = at = __alloca (sizeof (struct gaih_addrtuple));
914 memset (at, '\0', sizeof (struct gaih_addrtuple));
915
916 if (req->ai_family == AF_UNSPEC)
917 {
918 at->next = __alloca (sizeof (struct gaih_addrtuple));
919 memset (at->next, '\0', sizeof (struct gaih_addrtuple));
920 }
921
922 if (req->ai_family == AF_UNSPEC || req->ai_family == AF_INET6)
923 {
924 at->family = AF_INET6;
925 if ((req->ai_flags & AI_PASSIVE) == 0)
926 memcpy (at->addr, &in6addr_loopback, sizeof (struct in6_addr));
927 atr = at->next;
928 }
929
930 if (req->ai_family == AF_UNSPEC || req->ai_family == AF_INET)
931 {
932 atr->family = AF_INET;
933 if ((req->ai_flags & AI_PASSIVE) == 0)
934 atr->addr[0] = htonl (INADDR_LOOPBACK);
935 }
936 }
937
938 if (pai == NULL)
939 return 0;
940
941 {
942 struct gaih_servtuple *st2;
943 struct gaih_addrtuple *at2 = at;
944 size_t socklen;
945 sa_family_t family;
946
947 /*
948 buffer is the size of an unformatted IPv6 address in printable format.
949 */
950 while (at2 != NULL)
951 {
952 /* Only the first entry gets the canonical name. */
953 if (at2 == at && (req->ai_flags & AI_CANONNAME) != 0)
954 {
955 if (canon == NULL)
956 {
957 struct hostent *h = NULL;
958 int herrno;
959 struct hostent th;
960 size_t tmpbuflen = 512;
961 char *tmpbuf = NULL;
962
963 do
964 {
965 tmpbuf = extend_alloca (tmpbuf, tmpbuflen, tmpbuflen * 2);
966 rc = __gethostbyaddr_r (at2->addr,
967 ((at2->family == AF_INET6)
968 ? sizeof (struct in6_addr)
969 : sizeof (struct in_addr)),
970 at2->family, &th, tmpbuf,
971 tmpbuflen, &h, &herrno);
972 }
973 while (rc == ERANGE && herrno == NETDB_INTERNAL);
974
975 if (rc != 0 && herrno == NETDB_INTERNAL)
976 {
977 __set_h_errno (herrno);
978 return -EAI_SYSTEM;
979 }
980
981 if (h != NULL)
982 canon = h->h_name;
983 else
984 {
985 assert (orig_name != NULL);
986 /* If the canonical name cannot be determined, use
987 the passed in string. */
988 canon = orig_name;
989 }
990 }
991
992 #ifdef HAVE_LIBIDN
993 if (req->ai_flags & AI_CANONIDN)
994 {
995 int idn_flags = 0;
996 if (req->ai_flags & AI_IDN_ALLOW_UNASSIGNED)
997 idn_flags |= IDNA_ALLOW_UNASSIGNED;
998 if (req->ai_flags & AI_IDN_USE_STD3_ASCII_RULES)
999 idn_flags |= IDNA_USE_STD3_ASCII_RULES;
1000
1001 char *out;
1002 int rc = __idna_to_unicode_lzlz (canon, &out, idn_flags);
1003 if (rc != IDNA_SUCCESS)
1004 {
1005 if (rc == IDNA_MALLOC_ERROR)
1006 return -EAI_MEMORY;
1007 if (rc == IDNA_DLOPEN_ERROR)
1008 return -EAI_SYSTEM;
1009 return -EAI_IDN_ENCODE;
1010 }
1011 /* In case the output string is the same as the input
1012 string no new string has been allocated. Otherwise
1013 make a copy. */
1014 if (out == canon)
1015 goto make_copy;
1016 }
1017 else
1018 #endif
1019 {
1020 #ifdef HAVE_LIBIDN
1021 make_copy:
1022 #endif
1023 canon = strdup (canon);
1024 if (canon == NULL)
1025 return -EAI_MEMORY;
1026 }
1027 }
1028
1029 family = at2->family;
1030 if (family == AF_INET6)
1031 {
1032 socklen = sizeof (struct sockaddr_in6);
1033
1034 /* If we looked up IPv4 mapped address discard them here if
1035 the caller isn't interested in all address and we have
1036 found at least one IPv6 address. */
1037 if (got_ipv6
1038 && (req->ai_flags & (AI_V4MAPPED|AI_ALL)) == AI_V4MAPPED
1039 && IN6_IS_ADDR_V4MAPPED (at2->addr))
1040 goto ignore;
1041 }
1042 else
1043 socklen = sizeof (struct sockaddr_in);
1044
1045 for (st2 = st; st2 != NULL; st2 = st2->next)
1046 {
1047 struct addrinfo *ai;
1048 ai = *pai = malloc (sizeof (struct addrinfo) + socklen);
1049 if (ai == NULL)
1050 {
1051 free ((char *) canon);
1052 return -EAI_MEMORY;
1053 }
1054
1055 ai->ai_flags = req->ai_flags;
1056 ai->ai_family = family;
1057 ai->ai_socktype = st2->socktype;
1058 ai->ai_protocol = st2->protocol;
1059 ai->ai_addrlen = socklen;
1060 ai->ai_addr = (void *) (ai + 1);
1061
1062 /* We only add the canonical name once. */
1063 ai->ai_canonname = (char *) canon;
1064 canon = NULL;
1065
1066 #ifdef _HAVE_SA_LEN
1067 ai->ai_addr->sa_len = socklen;
1068 #endif /* _HAVE_SA_LEN */
1069 ai->ai_addr->sa_family = family;
1070
1071 /* In case of an allocation error the list must be NULL
1072 terminated. */
1073 ai->ai_next = NULL;
1074
1075 if (family == AF_INET6)
1076 {
1077 struct sockaddr_in6 *sin6p =
1078 (struct sockaddr_in6 *) ai->ai_addr;
1079
1080 sin6p->sin6_port = st2->port;
1081 sin6p->sin6_flowinfo = 0;
1082 memcpy (&sin6p->sin6_addr,
1083 at2->addr, sizeof (struct in6_addr));
1084 sin6p->sin6_scope_id = at2->scopeid;
1085 }
1086 else
1087 {
1088 struct sockaddr_in *sinp =
1089 (struct sockaddr_in *) ai->ai_addr;
1090 sinp->sin_port = st2->port;
1091 memcpy (&sinp->sin_addr,
1092 at2->addr, sizeof (struct in_addr));
1093 memset (sinp->sin_zero, '\0', sizeof (sinp->sin_zero));
1094 }
1095
1096 pai = &(ai->ai_next);
1097 }
1098
1099 ++*naddrs;
1100
1101 ignore:
1102 at2 = at2->next;
1103 }
1104 }
1105 return 0;
1106 }
1107
1108 #if 0
1109 static const struct gaih gaih[] =
1110 {
1111 { PF_INET6, gaih_inet },
1112 { PF_INET, gaih_inet },
1113 #if 0
1114 { PF_LOCAL, gaih_local },
1115 #endif
1116 { PF_UNSPEC, NULL }
1117 };
1118 #endif
1119
1120 struct sort_result
1121 {
1122 struct addrinfo *dest_addr;
1123 struct sockaddr_storage source_addr;
1124 uint8_t source_addr_len;
1125 bool got_source_addr;
1126 uint8_t source_addr_flags;
1127 };
1128
1129
1130 static int
1131 get_scope (const struct sockaddr_storage *ss)
1132 {
1133 int scope;
1134 if (ss->ss_family == PF_INET6)
1135 {
1136 const struct sockaddr_in6 *in6 = (const struct sockaddr_in6 *) ss;
1137
1138 if (! IN6_IS_ADDR_MULTICAST (&in6->sin6_addr))
1139 {
1140 if (IN6_IS_ADDR_LINKLOCAL (&in6->sin6_addr))
1141 scope = 2;
1142 else if (IN6_IS_ADDR_SITELOCAL (&in6->sin6_addr))
1143 scope = 5;
1144 else
1145 /* XXX Is this the correct default behavior? */
1146 scope = 14;
1147 }
1148 else
1149 scope = in6->sin6_addr.s6_addr[1] & 0xf;
1150 }
1151 else if (ss->ss_family == PF_INET)
1152 {
1153 const struct sockaddr_in *in = (const struct sockaddr_in *) ss;
1154 const uint8_t *addr = (const uint8_t *) &in->sin_addr;
1155
1156 /* RFC 3484 specifies how to map IPv6 addresses to scopes.
1157 169.254/16 and 127/8 are link-local. */
1158 if ((addr[0] == 169 && addr[1] == 254) || addr[0] == 127)
1159 scope = 2;
1160 else if (addr[0] == 10 || (addr[0] == 172 && addr[1] == 16)
1161 || (addr[0] == 192 && addr[1] == 168))
1162 scope = 5;
1163 else
1164 scope = 14;
1165 }
1166 else
1167 /* XXX What is a good default? */
1168 scope = 15;
1169
1170 return scope;
1171 }
1172
1173
1174 struct prefixentry
1175 {
1176 struct in6_addr prefix;
1177 unsigned int bits;
1178 int val;
1179 };
1180
1181
1182 /* The label table. */
1183 static const struct prefixentry *labels;
1184
1185 /* Default labels. */
1186 static const struct prefixentry default_labels[] =
1187 {
1188 /* See RFC 3484 for the details. */
1189 { { .in6_u
1190 = { .u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
1191 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01 } } },
1192 128, 0 },
1193 { { .in6_u
1194 = { .u6_addr8 = { 0x20, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
1195 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } } },
1196 16, 2 },
1197 { { .in6_u
1198 = { .u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
1199 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } } },
1200 96, 3 },
1201 { { .in6_u
1202 = { .u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
1203 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00 } } },
1204 96, 4 },
1205 { { .in6_u
1206 = { .u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
1207 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } } },
1208 0, 1 }
1209 };
1210
1211
1212 /* The precedence table. */
1213 static const struct prefixentry *precedence;
1214
1215 /* The default precedences. */
1216 static const struct prefixentry default_precedence[] =
1217 {
1218 /* See RFC 3484 for the details. */
1219 { { .in6_u
1220 = { .u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
1221 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01 } } },
1222 128, 50 },
1223 { { .in6_u
1224 = { .u6_addr8 = { 0x20, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
1225 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } } },
1226 16, 30 },
1227 { { .in6_u
1228 = { .u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
1229 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } } },
1230 96, 20 },
1231 { { .in6_u
1232 = { .u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
1233 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00 } } },
1234 96, 100 },
1235 { { .in6_u
1236 = { .u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
1237 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } } },
1238 0, 40 }
1239 };
1240
1241
1242 static int
1243 match_prefix (const struct sockaddr_storage *ss,
1244 const struct prefixentry *list, int default_val)
1245 {
1246 int idx;
1247 struct sockaddr_in6 in6_mem;
1248 const struct sockaddr_in6 *in6;
1249
1250 if (ss->ss_family == PF_INET6)
1251 in6 = (const struct sockaddr_in6 *) ss;
1252 else if (ss->ss_family == PF_INET)
1253 {
1254 const struct sockaddr_in *in = (const struct sockaddr_in *) ss;
1255
1256 /* Convert to IPv6 address. */
1257 in6_mem.sin6_family = PF_INET6;
1258 in6_mem.sin6_port = in->sin_port;
1259 in6_mem.sin6_flowinfo = 0;
1260 if (in->sin_addr.s_addr == htonl (0x7f000001))
1261 in6_mem.sin6_addr = (struct in6_addr) IN6ADDR_LOOPBACK_INIT;
1262 else
1263 {
1264 /* Construct a V4-to-6 mapped address. */
1265 memset (&in6_mem.sin6_addr, '\0', sizeof (in6_mem.sin6_addr));
1266 in6_mem.sin6_addr.s6_addr16[5] = 0xffff;
1267 in6_mem.sin6_addr.s6_addr32[3] = in->sin_addr.s_addr;
1268 in6_mem.sin6_scope_id = 0;
1269 }
1270
1271 in6 = &in6_mem;
1272 }
1273 else
1274 return default_val;
1275
1276 for (idx = 0; ; ++idx)
1277 {
1278 unsigned int bits = list[idx].bits;
1279 uint8_t *mask = list[idx].prefix.s6_addr;
1280 uint8_t *val = in6->sin6_addr.s6_addr;
1281
1282 while (bits >= 8)
1283 {
1284 if (*mask != *val)
1285 break;
1286
1287 ++mask;
1288 ++val;
1289 bits -= 8;
1290 }
1291
1292 if (bits < 8)
1293 {
1294 if ((*mask & (0xff00 >> bits)) == (*val & (0xff00 >> bits)))
1295 /* Match! */
1296 break;
1297 }
1298 }
1299
1300 return list[idx].val;
1301 }
1302
1303
1304 static int
1305 get_label (const struct sockaddr_storage *ss)
1306 {
1307 /* XXX What is a good default value? */
1308 return match_prefix (ss, labels, INT_MAX);
1309 }
1310
1311
1312 static int
1313 get_precedence (const struct sockaddr_storage *ss)
1314 {
1315 /* XXX What is a good default value? */
1316 return match_prefix (ss, precedence, 0);
1317 }
1318
1319
1320 /* Find last bit set in a word. */
1321 static int
1322 fls (uint32_t a)
1323 {
1324 uint32_t mask;
1325 int n = 0;
1326 for (n = 0, mask = 1 << 31; n < 32; mask >>= 1, ++n)
1327 if ((a & mask) != 0)
1328 break;
1329 return n;
1330 }
1331
1332
1333 static int
1334 rfc3484_sort (const void *p1, const void *p2)
1335 {
1336 const struct sort_result *a1 = (const struct sort_result *) p1;
1337 const struct sort_result *a2 = (const struct sort_result *) p2;
1338
1339 /* Rule 1: Avoid unusable destinations.
1340 We have the got_source_addr flag set if the destination is reachable. */
1341 if (a1->got_source_addr && ! a2->got_source_addr)
1342 return -1;
1343 if (! a1->got_source_addr && a2->got_source_addr)
1344 return 1;
1345
1346
1347 /* Rule 2: Prefer matching scope. Only interesting if both
1348 destination addresses are IPv6. */
1349 int a1_dst_scope
1350 = get_scope ((struct sockaddr_storage *) a1->dest_addr->ai_addr);
1351
1352 int a2_dst_scope
1353 = get_scope ((struct sockaddr_storage *) a2->dest_addr->ai_addr);
1354
1355 if (a1->got_source_addr)
1356 {
1357 int a1_src_scope = get_scope (&a1->source_addr);
1358 int a2_src_scope = get_scope (&a2->source_addr);
1359
1360 if (a1_dst_scope == a1_src_scope && a2_dst_scope != a2_src_scope)
1361 return -1;
1362 if (a1_dst_scope != a1_src_scope && a2_dst_scope == a2_src_scope)
1363 return 1;
1364 }
1365
1366
1367 /* Rule 3: Avoid deprecated addresses. */
1368 if (a1->got_source_addr)
1369 {
1370 if (!(a1->source_addr_flags & in6ai_deprecated)
1371 && (a2->source_addr_flags & in6ai_deprecated))
1372 return -1;
1373 if ((a1->source_addr_flags & in6ai_deprecated)
1374 && !(a2->source_addr_flags & in6ai_deprecated))
1375 return 1;
1376 }
1377
1378 /* Rule 4: Prefer home addresses.
1379 Another thing only the kernel can decide. */
1380
1381 /* Rule 5: Prefer matching label. */
1382 if (a1->got_source_addr)
1383 {
1384 int a1_dst_label
1385 = get_label ((struct sockaddr_storage *) a1->dest_addr->ai_addr);
1386 int a1_src_label = get_label (&a1->source_addr);
1387
1388 int a2_dst_label
1389 = get_label ((struct sockaddr_storage *) a2->dest_addr->ai_addr);
1390 int a2_src_label = get_label (&a2->source_addr);
1391
1392 if (a1_dst_label == a1_src_label && a2_dst_label != a2_src_label)
1393 return -1;
1394 if (a1_dst_label != a1_src_label && a2_dst_label == a2_src_label)
1395 return 1;
1396 }
1397
1398
1399 /* Rule 6: Prefer higher precedence. */
1400 int a1_prec
1401 = get_precedence ((struct sockaddr_storage *) a1->dest_addr->ai_addr);
1402 int a2_prec
1403 = get_precedence ((struct sockaddr_storage *) a2->dest_addr->ai_addr);
1404
1405 if (a1_prec > a2_prec)
1406 return -1;
1407 if (a1_prec < a2_prec)
1408 return 1;
1409
1410
1411 /* Rule 7: Prefer native transport. */
1412 if (a1->got_source_addr)
1413 {
1414 if (!(a1->source_addr_flags & in6ai_temporary)
1415 && (a1->source_addr_flags & in6ai_temporary))
1416 return -1;
1417 if ((a1->source_addr_flags & in6ai_temporary)
1418 && !(a1->source_addr_flags & in6ai_temporary))
1419 return -1;
1420
1421 /* XXX Do we need to check anything beside temporary addresses? */
1422 }
1423
1424
1425 /* Rule 8: Prefer smaller scope. */
1426 if (a1_dst_scope < a2_dst_scope)
1427 return -1;
1428 if (a1_dst_scope > a2_dst_scope)
1429 return 1;
1430
1431
1432 /* Rule 9: Use longest matching prefix. */
1433 if (a1->got_source_addr
1434 && a1->dest_addr->ai_family == a2->dest_addr->ai_family)
1435 {
1436 int bit1 = 0;
1437 int bit2 = 0;
1438
1439 if (a1->dest_addr->ai_family == PF_INET)
1440 {
1441 assert (a1->source_addr.ss_family == PF_INET);
1442 assert (a2->source_addr.ss_family == PF_INET);
1443
1444 struct sockaddr_in *in1_dst;
1445 struct sockaddr_in *in1_src;
1446 struct sockaddr_in *in2_dst;
1447 struct sockaddr_in *in2_src;
1448
1449 in1_dst = (struct sockaddr_in *) a1->dest_addr->ai_addr;
1450 in1_src = (struct sockaddr_in *) &a1->source_addr;
1451 in2_dst = (struct sockaddr_in *) a2->dest_addr->ai_addr;
1452 in2_src = (struct sockaddr_in *) &a2->source_addr;
1453
1454 bit1 = fls (ntohl (in1_dst->sin_addr.s_addr
1455 ^ in1_src->sin_addr.s_addr));
1456 bit2 = fls (ntohl (in2_dst->sin_addr.s_addr
1457 ^ in2_src->sin_addr.s_addr));
1458 }
1459 else if (a1->dest_addr->ai_family == PF_INET6)
1460 {
1461 assert (a1->source_addr.ss_family == PF_INET6);
1462 assert (a2->source_addr.ss_family == PF_INET6);
1463
1464 struct sockaddr_in6 *in1_dst;
1465 struct sockaddr_in6 *in1_src;
1466 struct sockaddr_in6 *in2_dst;
1467 struct sockaddr_in6 *in2_src;
1468
1469 in1_dst = (struct sockaddr_in6 *) a1->dest_addr->ai_addr;
1470 in1_src = (struct sockaddr_in6 *) &a1->source_addr;
1471 in2_dst = (struct sockaddr_in6 *) a2->dest_addr->ai_addr;
1472 in2_src = (struct sockaddr_in6 *) &a2->source_addr;
1473
1474 int i;
1475 for (i = 0; i < 4; ++i)
1476 if (in1_dst->sin6_addr.s6_addr32[i]
1477 != in1_src->sin6_addr.s6_addr32[i]
1478 || (in2_dst->sin6_addr.s6_addr32[i]
1479 != in2_src->sin6_addr.s6_addr32[i]))
1480 break;
1481
1482 if (i < 4)
1483 {
1484 bit1 = fls (ntohl (in1_dst->sin6_addr.s6_addr32[i]
1485 ^ in1_src->sin6_addr.s6_addr32[i]));
1486 bit2 = fls (ntohl (in2_dst->sin6_addr.s6_addr32[i]
1487 ^ in2_src->sin6_addr.s6_addr32[i]));
1488 }
1489 }
1490
1491 if (bit1 > bit2)
1492 return -1;
1493 if (bit1 < bit2)
1494 return 1;
1495 }
1496
1497
1498 /* Rule 10: Otherwise, leave the order unchanged. */
1499 return 0;
1500 }
1501
1502
1503 static int
1504 in6aicmp (const void *p1, const void *p2)
1505 {
1506 struct in6addrinfo *a1 = (struct in6addrinfo *) p1;
1507 struct in6addrinfo *a2 = (struct in6addrinfo *) p2;
1508
1509 return memcmp (a1->addr, a2->addr, sizeof (a1->addr));
1510 }
1511
1512
1513 /* Name of the config file for RFC 3484 sorting (for now). */
1514 #define GAICONF_FNAME "/etc/gai.conf"
1515
1516
1517 /* Nozero if we are supposed to reload the config file automatically
1518 whenever it changed. */
1519 static int gaiconf_reload_flag;
1520
1521 /* Last modification time. */
1522 static struct timespec gaiconf_mtime;
1523
1524
1525 libc_freeres_fn(fini)
1526 {
1527 if (labels != default_labels)
1528 {
1529 const struct prefixentry *old = labels;
1530 labels = default_labels;
1531 free ((void *) old);
1532 }
1533
1534 if (precedence != default_precedence)
1535 {
1536 const struct prefixentry *old = precedence;
1537 precedence = default_precedence;
1538 free ((void *) old);
1539 }
1540 }
1541
1542
1543 struct prefixlist
1544 {
1545 struct prefixentry entry;
1546 struct prefixlist *next;
1547 };
1548
1549
1550 static void
1551 free_prefixlist (struct prefixlist *list)
1552 {
1553 while (list != NULL)
1554 {
1555 struct prefixlist *oldp = list;
1556 list = list->next;
1557 free (oldp);
1558 }
1559 }
1560
1561
1562 static int
1563 prefixcmp (const void *p1, const void *p2)
1564 {
1565 const struct prefixentry *e1 = (const struct prefixentry *) p1;
1566 const struct prefixentry *e2 = (const struct prefixentry *) p2;
1567
1568 if (e1->bits < e2->bits)
1569 return 1;
1570 if (e1->bits == e2->bits)
1571 return 0;
1572 return -1;
1573 }
1574
1575
1576 static void
1577 gaiconf_init (void)
1578 {
1579 struct prefixlist *labellist = NULL;
1580 size_t nlabellist = 0;
1581 bool labellist_nullbits = false;
1582 struct prefixlist *precedencelist = NULL;
1583 size_t nprecedencelist = 0;
1584 bool precedencelist_nullbits = false;
1585
1586 FILE *fp = fopen (GAICONF_FNAME, "rc");
1587 if (fp != NULL)
1588 {
1589 struct stat64 st;
1590 if (__fxstat64 (_STAT_VER, fileno (fp), &st) != 0)
1591 {
1592 fclose (fp);
1593 goto no_file;
1594 }
1595
1596 char *line = NULL;
1597 size_t linelen = 0;
1598
1599 __fsetlocking (fp, FSETLOCKING_BYCALLER);
1600
1601 while (!feof_unlocked (fp))
1602 {
1603 ssize_t n = __getline (&line, &linelen, fp);
1604 if (n <= 0)
1605 break;
1606
1607 /* Handle comments. No escaping possible so this is easy. */
1608 char *cp = strchr (line, '#');
1609 if (cp != NULL)
1610 *cp = '\0';
1611
1612 cp = line;
1613 while (isspace (*cp))
1614 ++cp;
1615
1616 char *cmd = cp;
1617 while (*cp != '\0' && !isspace (*cp))
1618 ++cp;
1619 size_t cmdlen = cp - cmd;
1620
1621 if (*cp != '\0')
1622 *cp++ = '\0';
1623 while (isspace (*cp))
1624 ++cp;
1625
1626 char *val1 = cp;
1627 while (*cp != '\0' && !isspace (*cp))
1628 ++cp;
1629 size_t val1len = cp - cmd;
1630
1631 /* We always need at least two values. */
1632 if (val1len == 0)
1633 continue;
1634
1635 if (*cp != '\0')
1636 *cp++ = '\0';
1637 while (isspace (*cp))
1638 ++cp;
1639
1640 char *val2 = cp;
1641 while (*cp != '\0' && !isspace (*cp))
1642 ++cp;
1643
1644 /* Ignore the rest of the line. */
1645 *cp = '\0';
1646
1647 struct prefixlist **listp;
1648 size_t *lenp;
1649 bool *nullbitsp;
1650 switch (cmdlen)
1651 {
1652 case 5:
1653 if (strcmp (cmd, "label") == 0)
1654 {
1655 struct in6_addr prefix;
1656 unsigned long int bits = 128;
1657 unsigned long int val;
1658 char *endp;
1659
1660 listp = &labellist;
1661 lenp = &nlabellist;
1662 nullbitsp = &labellist_nullbits;
1663
1664 new_elem:
1665 __set_errno (0);
1666 cp = strchr (val1, '/');
1667 if (cp != NULL)
1668 *cp++ = '\0';
1669 if (inet_pton (AF_INET6, val1, &prefix)
1670 && (cp == NULL
1671 || (bits = strtoul (cp, &endp, 10)) != ULONG_MAX
1672 || errno != ERANGE)
1673 && *endp == '\0'
1674 && bits <= INT_MAX
1675 && ((val = strtoul (val2, &endp, 10)) != ULONG_MAX
1676 || errno != ERANGE)
1677 && *endp == '\0'
1678 && val <= INT_MAX)
1679 {
1680 struct prefixlist *newp = malloc (sizeof (*newp));
1681 if (newp == NULL)
1682 {
1683 free (line);
1684 fclose (fp);
1685 goto no_file;
1686 }
1687
1688 memcpy (&newp->entry.prefix, &prefix, sizeof (prefix));
1689 newp->entry.bits = bits;
1690 newp->entry.val = val;
1691 newp->next = *listp;
1692 *listp = newp;
1693 ++*lenp;
1694 *nullbitsp |= bits == 0;
1695 }
1696 }
1697 break;
1698
1699 case 6:
1700 if (strcmp (cmd, "reload") == 0)
1701 gaiconf_reload_flag = strcmp (val1, "yes") == 0;
1702 break;
1703
1704 case 10:
1705 if (strcmp (cmd, "precedence") == 0)
1706 {
1707 listp = &precedencelist;
1708 lenp = &nprecedencelist;
1709 nullbitsp = &precedencelist_nullbits;
1710 goto new_elem;
1711 }
1712 break;
1713 }
1714 }
1715
1716 free (line);
1717
1718 fclose (fp);
1719
1720 /* Create the array for the labels. */
1721 struct prefixentry *new_labels;
1722 if (nlabellist > 0)
1723 {
1724 if (!labellist_nullbits)
1725 ++nlabellist;
1726 new_labels = malloc (nlabellist * sizeof (*new_labels));
1727 if (new_labels == NULL)
1728 goto no_file;
1729
1730 int i = nlabellist;
1731 if (!labellist_nullbits)
1732 {
1733 --i;
1734 memset (&new_labels[i].prefix, '\0', sizeof (struct in6_addr));
1735 new_labels[i].bits = 0;
1736 new_labels[i].val = 1;
1737 }
1738
1739 struct prefixlist *l = labellist;
1740 while (i-- > 0)
1741 {
1742 new_labels[i] = l->entry;
1743 l = l->next;
1744 }
1745 free_prefixlist (labellist);
1746
1747 /* Sort the entries so that the most specific ones are at
1748 the beginning. */
1749 qsort (new_labels, nlabellist, sizeof (*new_labels), prefixcmp);
1750 }
1751 else
1752 new_labels = (struct prefixentry *) default_labels;
1753
1754 struct prefixentry *new_precedence;
1755 if (nprecedencelist > 0)
1756 {
1757 if (!precedencelist_nullbits)
1758 ++nprecedencelist;
1759 new_precedence = malloc (nprecedencelist * sizeof (*new_precedence));
1760 if (new_precedence == NULL)
1761 {
1762 if (new_labels != default_labels)
1763 free (new_labels);
1764 goto no_file;
1765 }
1766
1767 int i = nprecedencelist;
1768 if (!precedencelist_nullbits)
1769 {
1770 --i;
1771 memset (&new_precedence[i].prefix, '\0',
1772 sizeof (struct in6_addr));
1773 new_precedence[i].bits = 0;
1774 new_precedence[i].val = 40;
1775 }
1776
1777 struct prefixlist *l = precedencelist;
1778 while (i-- > 0)
1779 {
1780 new_precedence[i] = l->entry;
1781 l = l->next;
1782 }
1783 free_prefixlist (precedencelist);
1784
1785 /* Sort the entries so that the most specific ones are at
1786 the beginning. */
1787 qsort (new_precedence, nprecedencelist, sizeof (*new_labels),
1788 prefixcmp);
1789 }
1790 else
1791 new_precedence = (struct prefixentry *) default_precedence;
1792
1793 /* Now we are ready to replace the values. */
1794 const struct prefixentry *old = labels;
1795 labels = new_labels;
1796 if (old != default_labels)
1797 free ((void *) old);
1798
1799 old = precedence;
1800 precedence = new_precedence;
1801 if (old != default_precedence)
1802 free ((void *) old);
1803
1804 gaiconf_mtime = st.st_mtim;
1805 }
1806 else
1807 {
1808 no_file:
1809 free_prefixlist (labellist);
1810 free_prefixlist (precedencelist);
1811
1812 /* If we previously read the file but it is gone now, free the
1813 old data and use the builtin one. Leave the reload flag
1814 alone. */
1815 fini ();
1816 }
1817 }
1818
1819
1820 static void
1821 gaiconf_reload (void)
1822 {
1823 struct stat64 st;
1824 if (__xstat64 (_STAT_VER, GAICONF_FNAME, &st) != 0
1825 || memcmp (&st.st_mtim, &gaiconf_mtime, sizeof (gaiconf_mtime)) != 0)
1826 gaiconf_init ();
1827 }
1828
1829
1830 int
1831 getaddrinfo (const char *name, const char *service,
1832 const struct addrinfo *hints, struct addrinfo **pai)
1833 {
1834 int i = 0, last_i = 0;
1835 int nresults = 0;
1836 struct addrinfo *p = NULL;
1837 struct gaih_service gaih_service, *pservice;
1838 struct addrinfo local_hints;
1839
1840 if (name != NULL && name[0] == '*' && name[1] == 0)
1841 name = NULL;
1842
1843 if (service != NULL && service[0] == '*' && service[1] == 0)
1844 service = NULL;
1845
1846 if (name == NULL && service == NULL)
1847 return EAI_NONAME;
1848
1849 if (hints == NULL)
1850 hints = &default_hints;
1851
1852 if (hints->ai_flags
1853 & ~(AI_PASSIVE|AI_CANONNAME|AI_NUMERICHOST|AI_ADDRCONFIG|AI_V4MAPPED
1854 #ifdef HAVE_LIBIDN
1855 |AI_IDN|AI_CANONIDN|AI_IDN_ALLOW_UNASSIGNED
1856 |AI_IDN_USE_STD3_ASCII_RULES
1857 #endif
1858 |AI_NUMERICSERV|AI_ALL))
1859 return EAI_BADFLAGS;
1860
1861 if ((hints->ai_flags & AI_CANONNAME) && name == NULL)
1862 return EAI_BADFLAGS;
1863
1864 struct in6addrinfo *in6ai = NULL;
1865 size_t in6ailen;
1866 bool seen_ipv4 = false;
1867 bool seen_ipv6 = false;
1868 /* We might need information about what kind of interfaces are available.
1869 But even if AI_ADDRCONFIG is not used, if the user requested IPv6
1870 addresses we have to know whether an address is deprecated or
1871 temporary. */
1872 if ((hints->ai_flags & AI_ADDRCONFIG) || hints->ai_family == PF_UNSPEC
1873 || hints->ai_family == PF_INET6)
1874 /* Determine whether we have IPv4 or IPv6 interfaces or both. We
1875 cannot cache the results since new interfaces could be added at
1876 any time. */
1877 __check_pf (&seen_ipv4, &seen_ipv6, &in6ai, &in6ailen);
1878
1879 if (hints->ai_flags & AI_ADDRCONFIG)
1880 {
1881 /* Now make a decision on what we return, if anything. */
1882 if (hints->ai_family == PF_UNSPEC && (seen_ipv4 || seen_ipv6))
1883 {
1884 /* If we haven't seen both IPv4 and IPv6 interfaces we can
1885 narrow down the search. */
1886 if (! seen_ipv4 || ! seen_ipv6)
1887 {
1888 local_hints = *hints;
1889 local_hints.ai_family = seen_ipv4 ? PF_INET : PF_INET6;
1890 hints = &local_hints;
1891 }
1892 }
1893 else if ((hints->ai_family == PF_INET && ! seen_ipv4)
1894 || (hints->ai_family == PF_INET6 && ! seen_ipv6))
1895 {
1896 /* We cannot possibly return a valid answer. */
1897 free (in6ai);
1898 return EAI_NONAME;
1899 }
1900 }
1901
1902 if (service && service[0])
1903 {
1904 char *c;
1905 gaih_service.name = service;
1906 gaih_service.num = strtoul (gaih_service.name, &c, 10);
1907 if (*c != '\0')
1908 {
1909 if (hints->ai_flags & AI_NUMERICSERV)
1910 {
1911 free (in6ai);
1912 return EAI_NONAME;
1913 }
1914
1915 gaih_service.num = -1;
1916 }
1917
1918 pservice = &gaih_service;
1919 }
1920 else
1921 pservice = NULL;
1922
1923 struct addrinfo **end;
1924 if (pai)
1925 end = &p;
1926 else
1927 end = NULL;
1928
1929 unsigned int naddrs = 0;
1930 #if 0
1931 /* If we would support more protocols than just IPv4 and IPv6 we
1932 would iterate over a table with appropriate callback functions.
1933 Since we currently only handle IPv4 and IPv6 this is not
1934 necessary. */
1935 const struct gaih *g = gaih;
1936 const struct gaih *pg = NULL;
1937 int j = 0;
1938 while (g->gaih)
1939 {
1940 if (hints->ai_family == g->family || hints->ai_family == AF_UNSPEC)
1941 {
1942 j++;
1943 if (pg == NULL || pg->gaih != g->gaih)
1944 {
1945 pg = g;
1946 i = g->gaih (name, pservice, hints, end, &naddrs);
1947 if (i != 0)
1948 {
1949 /* EAI_NODATA is a more specific result as it says that
1950 we found a result but it is not usable. */
1951 if (last_i != (GAIH_OKIFUNSPEC | -EAI_NODATA))
1952 last_i = i;
1953
1954 if (hints->ai_family == AF_UNSPEC && (i & GAIH_OKIFUNSPEC))
1955 {
1956 ++g;
1957 continue;
1958 }
1959
1960 freeaddrinfo (p);
1961 free (in6ai);
1962
1963 return -(i & GAIH_EAI);
1964 }
1965 if (end)
1966 while (*end)
1967 {
1968 end = &((*end)->ai_next);
1969 ++nresults;
1970 }
1971 }
1972 }
1973 ++g;
1974 }
1975
1976 if (j == 0)
1977 {
1978 free (in6ai);
1979 return EAI_FAMILY;
1980 }
1981 #else
1982 if (hints->ai_family == AF_UNSPEC || hints->ai_family == AF_INET
1983 || hints->ai_family == AF_INET6)
1984 {
1985 last_i = gaih_inet (name, pservice, hints, end, &naddrs);
1986 if (last_i != 0)
1987 {
1988 freeaddrinfo (p);
1989 free (in6ai);
1990
1991 return -(last_i & GAIH_EAI);
1992 }
1993 if (end)
1994 while (*end)
1995 {
1996 end = &((*end)->ai_next);
1997 ++nresults;
1998 }
1999 }
2000 else
2001 {
2002 free (in6ai);
2003 return EAI_FAMILY;
2004 }
2005 #endif
2006
2007 if (naddrs > 1)
2008 {
2009 /* Read the config file. */
2010 __libc_once_define (static, once);
2011 __typeof (once) old_once = once;
2012 __libc_once (once, gaiconf_init);
2013 if (old_once && gaiconf_reload_flag)
2014 gaiconf_reload ();
2015
2016 /* Sort results according to RFC 3484. */
2017 struct sort_result results[nresults];
2018 struct addrinfo *q;
2019 struct addrinfo *last = NULL;
2020 char *canonname = NULL;
2021
2022 /* If we have information about deprecated and temporary address
2023 sort the array now. */
2024 if (in6ai != NULL)
2025 qsort (in6ai, in6ailen, sizeof (*in6ai), in6aicmp);
2026
2027 for (i = 0, q = p; q != NULL; ++i, last = q, q = q->ai_next)
2028 {
2029 results[i].dest_addr = q;
2030 results[i].got_source_addr = false;
2031
2032 /* If we just looked up the address for a different
2033 protocol, reuse the result. */
2034 if (last != NULL && last->ai_addrlen == q->ai_addrlen
2035 && memcmp (last->ai_addr, q->ai_addr, q->ai_addrlen) == 0)
2036 {
2037 memcpy (&results[i].source_addr, &results[i - 1].source_addr,
2038 results[i - 1].source_addr_len);
2039 results[i].source_addr_len = results[i - 1].source_addr_len;
2040 results[i].got_source_addr = results[i - 1].got_source_addr;
2041 results[i].source_addr_flags = results[i - 1].source_addr_flags;
2042 }
2043 else
2044 {
2045 results[i].source_addr_flags = 0;
2046
2047 /* We overwrite the type with SOCK_DGRAM since we do not
2048 want connect() to connect to the other side. If we
2049 cannot determine the source address remember this
2050 fact. */
2051 int fd = __socket (q->ai_family, SOCK_DGRAM, IPPROTO_IP);
2052 socklen_t sl = sizeof (results[i].source_addr);
2053 if (fd != -1
2054 && __connect (fd, q->ai_addr, q->ai_addrlen) == 0
2055 && __getsockname (fd,
2056 (struct sockaddr *) &results[i].source_addr,
2057 &sl) == 0)
2058 {
2059 results[i].source_addr_len = sl;
2060 results[i].got_source_addr = true;
2061
2062 if (q->ai_family == PF_INET6 && in6ai != NULL)
2063 {
2064 /* See whether the address is the list of deprecated
2065 or temporary addresses. */
2066 struct in6addrinfo tmp;
2067 memcpy (tmp.addr, q->ai_addr, IN6ADDRSZ);
2068
2069 struct in6addrinfo *found
2070 = bsearch (&tmp, in6ai, in6ailen, sizeof (*in6ai),
2071 in6aicmp);
2072 if (found != NULL)
2073 results[i].source_addr_flags = found->flags;
2074 }
2075 }
2076 else
2077 /* Just make sure that if we have to process the same
2078 address again we do not copy any memory. */
2079 results[i].source_addr_len = 0;
2080
2081 if (fd != -1)
2082 close_not_cancel_no_status (fd);
2083 }
2084
2085 /* Remember the canonical name. */
2086 if (q->ai_canonname != NULL)
2087 {
2088 assert (canonname == NULL);
2089 canonname = q->ai_canonname;
2090 q->ai_canonname = NULL;
2091 }
2092 }
2093
2094 /* We got all the source addresses we can get, now sort using
2095 the information. */
2096 qsort (results, nresults, sizeof (results[0]), rfc3484_sort);
2097
2098 /* Queue the results up as they come out of sorting. */
2099 q = p = results[0].dest_addr;
2100 for (i = 1; i < nresults; ++i)
2101 q = q->ai_next = results[i].dest_addr;
2102 q->ai_next = NULL;
2103
2104 /* Fill in the canonical name into the new first entry. */
2105 p->ai_canonname = canonname;
2106 }
2107
2108 free (in6ai);
2109
2110 if (p)
2111 {
2112 *pai = p;
2113 return 0;
2114 }
2115
2116 if (pai == NULL && last_i == 0)
2117 return 0;
2118
2119 return last_i ? -(last_i & GAIH_EAI) : EAI_NONAME;
2120 }
2121 libc_hidden_def (getaddrinfo)
2122
2123 static_link_warning (getaddrinfo)
2124
2125 void
2126 freeaddrinfo (struct addrinfo *ai)
2127 {
2128 struct addrinfo *p;
2129
2130 while (ai != NULL)
2131 {
2132 p = ai;
2133 ai = ai->ai_next;
2134 free (p->ai_canonname);
2135 free (p);
2136 }
2137 }
2138 libc_hidden_def (freeaddrinfo)
sources.redhat.com git mirror of glibc CVS