[BZ #2510, BZ #2830, BZ #3137, BZ #3313, BZ #3426, BZ #3465, BZ #3480, BZ #3483,...
[glibc.git] / sysdeps / posix / getaddrinfo.c
blobb4966852a72e274ddec1c56bb66845462edbef8d
1 /* The Inner Net License, Version 2.00
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:
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.
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.
34 If these license terms cause you a real problem, contact the author. */
36 /* This software is Copyright 1996 by Craig Metz, All Rights Reserved. */
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>
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
71 #define GAIH_OKIFUNSPEC 0x0100
72 #define GAIH_EAI ~(GAIH_OKIFUNSPEC)
74 #ifndef UNIX_PATH_MAX
75 # define UNIX_PATH_MAX 108
76 #endif
78 struct gaih_service
80 const char *name;
81 int num;
84 struct gaih_servtuple
86 struct gaih_servtuple *next;
87 int socktype;
88 int protocol;
89 int port;
92 static const struct gaih_servtuple nullserv;
94 struct gaih_addrtuple
96 struct gaih_addrtuple *next;
97 char *name;
98 int family;
99 uint32_t addr[4];
100 uint32_t scopeid;
103 struct gaih_typeproto
105 int socktype;
106 int protocol;
107 char name[4];
108 int protoflag;
111 /* Values for `protoflag'. */
112 #define GAI_PROTO_NOSERVICE 1
113 #define GAI_PROTO_PROTOANY 2
115 static const struct gaih_typeproto gaih_inet_typeproto[] =
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 }
124 struct gaih
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);
132 static const struct addrinfo default_hints =
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
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)
151 struct utsname utsname;
153 if ((name != NULL) && (req->ai_flags & AI_NUMERICHOST))
154 return GAIH_OKIFUNSPEC | -EAI_NONAME;
156 if ((name != NULL) || (req->ai_flags & AI_CANONNAME))
157 if (uname (&utsname) < 0)
158 return -EAI_SYSTEM;
160 if (name != NULL)
162 if (strcmp(name, "localhost") &&
163 strcmp(name, "local") &&
164 strcmp(name, "unix") &&
165 strcmp(name, utsname.nodename))
166 return GAIH_OKIFUNSPEC | -EAI_NONAME;
169 if (req->ai_protocol || req->ai_socktype)
171 const struct gaih_typeproto *tp = gaih_inet_typeproto + 1;
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;
181 if (! tp->name[0])
183 if (req->ai_socktype)
184 return GAIH_OKIFUNSPEC | -EAI_SOCKTYPE;
185 else
186 return GAIH_OKIFUNSPEC | -EAI_SERVICE;
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;
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);
204 #ifdef _HAVE_SA_LEN
205 ((struct sockaddr_un *) (*pai)->ai_addr)->sun_len =
206 sizeof (struct sockaddr_un);
207 #endif /* _HAVE_SA_LEN */
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);
212 if (service)
214 struct sockaddr_un *sunp = (struct sockaddr_un *) (*pai)->ai_addr;
216 if (strchr (service->name, '/') != NULL)
218 if (strlen (service->name) >= sizeof (sunp->sun_path))
219 return GAIH_OKIFUNSPEC | -EAI_SERVICE;
221 strcpy (sunp->sun_path, service->name);
223 else
225 if (strlen (P_tmpdir "/") + 1 + strlen (service->name) >=
226 sizeof (sunp->sun_path))
227 return GAIH_OKIFUNSPEC | -EAI_SERVICE;
229 __stpcpy (__stpcpy (sunp->sun_path, P_tmpdir "/"), service->name);
232 else
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;
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;
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;
254 #endif /* 0 */
257 static int
258 gaih_inet_serv (const char *servicename, const struct gaih_typeproto *tp,
259 const struct addrinfo *req, struct gaih_servtuple *st)
261 struct servent *s;
262 size_t tmpbuflen = 1024;
263 struct servent ts;
264 char *tmpbuf;
265 int r;
269 tmpbuf = __alloca (tmpbuflen);
271 r = __getservbyname_r (servicename, tp->name, &ts, tmpbuf, tmpbuflen,
272 &s);
273 if (r != 0 || s == NULL)
275 if (r == ERANGE)
276 tmpbuflen *= 2;
277 else
278 return GAIH_OKIFUNSPEC | -EAI_SERVICE;
281 while (r);
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;
289 return 0;
292 #define gethosts(_family, _type) \
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); \
308 if (status == NSS_STATUS_SUCCESS && rc == 0) \
309 h = &th; \
310 else \
311 h = NULL; \
312 if (rc != 0) \
314 if (herrno == NETDB_INTERNAL) \
316 __set_h_errno (herrno); \
317 return -EAI_SYSTEM; \
319 if (herrno == TRY_AGAIN) \
320 no_data = EAI_AGAIN; \
321 else \
322 no_data = herrno == NO_DATA; \
324 else if (h != NULL) \
326 for (i = 0; h->h_addr_list[i]; i++) \
328 if (*pat == NULL) \
330 *pat = __alloca (sizeof (struct gaih_addrtuple)); \
331 (*pat)->scopeid = 0; \
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) \
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; \
344 else \
346 (*pat)->family = _family; \
347 memcpy (addr, h->h_addr_list[i], sizeof(_type)); \
349 pat = &((*pat)->next); \
352 if (localcanon != NULL && canon == NULL) \
353 canon = strdupa (localcanon); \
355 if (_family == AF_INET6 && i > 0) \
356 got_ipv6 = true; \
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;
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)
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;
384 if (req->ai_protocol || req->ai_socktype)
386 ++tp;
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;
395 if (! tp->name[0])
397 if (req->ai_socktype)
398 return GAIH_OKIFUNSPEC | -EAI_SOCKTYPE;
399 else
400 return GAIH_OKIFUNSPEC | -EAI_SERVICE;
404 int port = 0;
405 if (service != NULL)
407 if ((tp->protoflag & GAI_PROTO_NOSERVICE) != 0)
408 return GAIH_OKIFUNSPEC | -EAI_SERVICE;
410 if (service->num < 0)
412 if (tp->name[0])
414 st = (struct gaih_servtuple *)
415 __alloca (sizeof (struct gaih_servtuple));
417 if ((rc = gaih_inet_serv (service->name, tp, req, st)))
418 return rc;
420 else
422 struct gaih_servtuple **pst = &st;
423 for (tp++; tp->name[0]; tp++)
425 struct gaih_servtuple *newp;
427 if ((tp->protoflag & GAI_PROTO_NOSERVICE) != 0)
428 continue;
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;
438 newp = (struct gaih_servtuple *)
439 __alloca (sizeof (struct gaih_servtuple));
441 if ((rc = gaih_inet_serv (service->name, tp, req, newp)))
443 if (rc & GAIH_OKIFUNSPEC)
444 continue;
445 return rc;
448 *pst = newp;
449 pst = &(newp->next);
451 if (st == (struct gaih_servtuple *) &nullserv)
452 return GAIH_OKIFUNSPEC | -EAI_SERVICE;
455 else
457 port = htons (service->num);
458 goto got_port;
461 else
463 got_port:
465 if (req->ai_socktype || req->ai_protocol)
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;
474 else
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)
481 struct gaih_servtuple *newp;
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;
489 *lastp = newp;
490 lastp = &newp->next;
495 if (name != NULL)
497 at = __alloca (sizeof (struct gaih_addrtuple));
499 at->family = AF_UNSPEC;
500 at->scopeid = 0;
501 at->next = NULL;
503 #ifdef HAVE_LIBIDN
504 if (req->ai_flags & AI_IDN)
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;
512 char *p = NULL;
513 rc = __idna_to_ascii_lz (name, &p, idn_flags);
514 if (rc != IDNA_SUCCESS)
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;
522 /* In case the output string is the same as the input string
523 no new string has been allocated. */
524 if (p != name)
526 name = strdupa (p);
527 free (p);
530 #endif
532 if (__inet_aton (name, (struct in_addr *) at->addr) != 0)
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))
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;
544 else
545 return -EAI_ADDRFAMILY;
547 if (req->ai_flags & AI_CANONNAME)
548 canon = name;
550 else if (at->family == AF_UNSPEC)
552 char *namebuf = (char *) name;
553 char *scope_delim = strchr (name, SCOPE_DELIMITER);
555 if (__builtin_expect (scope_delim != NULL, 0))
557 namebuf = alloca (scope_delim - name + 1);
558 *((char *) __mempcpy (namebuf, name, scope_delim - name)) = '\0';
561 if (inet_pton (AF_INET6, namebuf, at->addr) > 0)
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))
568 at->addr[0] = at->addr[3];
569 at->family = AF_INET;
571 else
572 return -EAI_ADDRFAMILY;
574 if (scope_delim != NULL)
576 int try_numericscope = 0;
577 if (IN6_IS_ADDR_LINKLOCAL (at->addr)
578 || IN6_IS_ADDR_MC_LINKLOCAL (at->addr))
580 at->scopeid = if_nametoindex (scope_delim + 1);
581 if (at->scopeid == 0)
582 try_numericscope = 1;
584 else
585 try_numericscope = 1;
587 if (try_numericscope != 0)
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;
598 if (req->ai_flags & AI_CANONNAME)
599 canon = name;
603 if (at->family == AF_UNSPEC && (req->ai_flags & AI_NUMERICHOST) == 0)
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;
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)))
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;
629 simple_again:
630 while (1)
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);
639 if (rc == 0)
641 if (h == NULL)
643 if (req->ai_family == AF_INET6
644 && (req->ai_flags & AI_V4MAPPED)
645 && family == AF_INET6)
647 /* Try again, this time looking for IPv4
648 addresses. */
649 family = AF_INET;
650 goto simple_again;
653 else
655 /* We found data, now convert it into the list. */
656 for (int i = 0; h->h_addr_list[i]; ++i)
658 if (*pat == NULL)
660 *pat = __alloca (sizeof (struct gaih_addrtuple));
661 (*pat)->scopeid = 0;
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
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;
676 pat = &((*pat)->next);
680 else
682 if (herrno == NETDB_INTERNAL)
684 __set_h_errno (herrno);
685 return -EAI_SYSTEM;
687 if (herrno == TRY_AGAIN)
689 return -EAI_AGAIN;
691 /* We made requests but they turned out no data.
692 The name is known, though. */
693 return GAIH_OKIFUNSPEC | -EAI_NODATA;
696 goto process_list;
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;
704 if (!__nss_not_use_nscd_hosts)
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)
712 /* Transform into gaih_addrtuple list. */
713 bool added_canon = (req->ai_flags & AI_CANONNAME) == 0;
714 char *addrs = air->addrs;
716 for (int i = 0; i < air->naddrs; ++i)
718 socklen_t size = (air->family[i] == AF_INET
719 ? INADDRSZ : IN6ADDRSZ);
720 if (*pat == NULL)
722 *pat = __alloca (sizeof (struct gaih_addrtuple));
723 (*pat)->scopeid = 0;
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);
732 if (air->family[i] == AF_INET
733 && req->ai_family == AF_INET6
734 && (req->ai_flags & AI_V4MAPPED))
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;
744 else if (req->ai_family == AF_UNSPEC
745 || air->family[i] == req->ai_family)
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;
754 addrs += size;
757 free (air);
759 if (at->family == AF_UNSPEC)
760 return GAIH_OKIFUNSPEC | -EAI_NONAME;
762 goto process_list;
764 else if (err != 0 && __nss_not_use_nscd_hosts == 0)
766 if (herrno == NETDB_INTERNAL && errno == ENOMEM)
767 return -EAI_MEMORY;
768 if (herrno == TRY_AGAIN)
769 return -EAI_AGAIN;
770 return -EAI_SYSTEM;
773 #endif
775 if (__nss_hosts_database != NULL)
777 no_more = 0;
778 nip = __nss_hosts_database;
780 else
781 no_more = __nss_database_lookup ("hosts", NULL,
782 "dns [!UNAVAIL=return] files",
783 &nip);
785 if (__res_maybe_init (&_res, 0) == -1)
786 no_more = 1;
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;
795 size_t tmpbuflen = 512;
796 char *tmpbuf = alloca (tmpbuflen);
798 while (!no_more)
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");
814 if (fct != NULL)
816 if (req->ai_family == AF_INET6
817 || req->ai_family == AF_UNSPEC)
819 gethosts (AF_INET6, struct in6_addr);
820 no_inet6_data = no_data;
821 inet6_status = status;
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)))
831 gethosts (AF_INET, struct in_addr);
833 if (req->ai_family == AF_INET)
835 no_inet6_data = no_data;
836 inet6_status = status;
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)
845 if ((req->ai_flags & AI_CANONNAME) != 0 && canon == NULL)
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;
852 cfct = __nss_lookup_function (nip, "getcanonname_r");
853 if (cfct != NULL)
855 const size_t max_fqdn_len = 256;
856 char *buf = alloca (max_fqdn_len);
857 char *s;
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;
871 break;
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;
883 if (nss_next_action (nip, status) == NSS_ACTION_RETURN)
884 break;
886 if (nip->next == NULL)
887 no_more = -1;
888 else
889 nip = nip->next;
892 _res.options = old_res_options;
894 if (no_data != 0 && no_inet6_data != 0)
896 /* If both requests timed out report this. */
897 if (no_data == EAI_AGAIN && no_inet6_data == EAI_AGAIN)
898 return -EAI_AGAIN;
900 /* We made requests but they turned out no data. The name
901 is known, though. */
902 return GAIH_OKIFUNSPEC | -EAI_NODATA;
906 process_list:
907 if (at->family == AF_UNSPEC)
908 return GAIH_OKIFUNSPEC | -EAI_NONAME;
910 else
912 struct gaih_addrtuple *atr;
913 atr = at = __alloca (sizeof (struct gaih_addrtuple));
914 memset (at, '\0', sizeof (struct gaih_addrtuple));
916 if (req->ai_family == AF_UNSPEC)
918 at->next = __alloca (sizeof (struct gaih_addrtuple));
919 memset (at->next, '\0', sizeof (struct gaih_addrtuple));
922 if (req->ai_family == AF_UNSPEC || req->ai_family == AF_INET6)
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;
930 if (req->ai_family == AF_UNSPEC || req->ai_family == AF_INET)
932 atr->family = AF_INET;
933 if ((req->ai_flags & AI_PASSIVE) == 0)
934 atr->addr[0] = htonl (INADDR_LOOPBACK);
938 if (pai == NULL)
939 return 0;
942 struct gaih_servtuple *st2;
943 struct gaih_addrtuple *at2 = at;
944 size_t socklen;
945 sa_family_t family;
948 buffer is the size of an unformatted IPv6 address in printable format.
950 while (at2 != NULL)
952 /* Only the first entry gets the canonical name. */
953 if (at2 == at && (req->ai_flags & AI_CANONNAME) != 0)
955 if (canon == NULL)
957 struct hostent *h = NULL;
958 int herrno;
959 struct hostent th;
960 size_t tmpbuflen = 512;
961 char *tmpbuf = NULL;
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);
973 while (rc == ERANGE && herrno == NETDB_INTERNAL);
975 if (rc != 0 && herrno == NETDB_INTERNAL)
977 __set_h_errno (herrno);
978 return -EAI_SYSTEM;
981 if (h != NULL)
982 canon = h->h_name;
983 else
985 assert (orig_name != NULL);
986 /* If the canonical name cannot be determined, use
987 the passed in string. */
988 canon = orig_name;
992 #ifdef HAVE_LIBIDN
993 if (req->ai_flags & AI_CANONIDN)
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;
1001 char *out;
1002 int rc = __idna_to_unicode_lzlz (canon, &out, idn_flags);
1003 if (rc != IDNA_SUCCESS)
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;
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;
1017 else
1018 #endif
1020 #ifdef HAVE_LIBIDN
1021 make_copy:
1022 #endif
1023 canon = strdup (canon);
1024 if (canon == NULL)
1025 return -EAI_MEMORY;
1029 family = at2->family;
1030 if (family == AF_INET6)
1032 socklen = sizeof (struct sockaddr_in6);
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;
1042 else
1043 socklen = sizeof (struct sockaddr_in);
1045 for (st2 = st; st2 != NULL; st2 = st2->next)
1047 struct addrinfo *ai;
1048 ai = *pai = malloc (sizeof (struct addrinfo) + socklen);
1049 if (ai == NULL)
1051 free ((char *) canon);
1052 return -EAI_MEMORY;
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);
1062 /* We only add the canonical name once. */
1063 ai->ai_canonname = (char *) canon;
1064 canon = NULL;
1066 #ifdef _HAVE_SA_LEN
1067 ai->ai_addr->sa_len = socklen;
1068 #endif /* _HAVE_SA_LEN */
1069 ai->ai_addr->sa_family = family;
1071 /* In case of an allocation error the list must be NULL
1072 terminated. */
1073 ai->ai_next = NULL;
1075 if (family == AF_INET6)
1077 struct sockaddr_in6 *sin6p =
1078 (struct sockaddr_in6 *) ai->ai_addr;
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;
1086 else
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));
1096 pai = &(ai->ai_next);
1099 ++*naddrs;
1101 ignore:
1102 at2 = at2->next;
1105 return 0;
1108 #if 0
1109 static const struct gaih gaih[] =
1111 { PF_INET6, gaih_inet },
1112 { PF_INET, gaih_inet },
1113 #if 0
1114 { PF_LOCAL, gaih_local },
1115 #endif
1116 { PF_UNSPEC, NULL }
1118 #endif
1120 struct sort_result
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;
1130 static int
1131 get_scope (const struct sockaddr_storage *ss)
1133 int scope;
1134 if (ss->ss_family == PF_INET6)
1136 const struct sockaddr_in6 *in6 = (const struct sockaddr_in6 *) ss;
1138 if (! IN6_IS_ADDR_MULTICAST (&in6->sin6_addr))
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;
1148 else
1149 scope = in6->sin6_addr.s6_addr[1] & 0xf;
1151 else if (ss->ss_family == PF_INET)
1153 const struct sockaddr_in *in = (const struct sockaddr_in *) ss;
1154 const uint8_t *addr = (const uint8_t *) &in->sin_addr;
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;
1166 else
1167 /* XXX What is a good default? */
1168 scope = 15;
1170 return scope;
1174 struct prefixentry
1176 struct in6_addr prefix;
1177 unsigned int bits;
1178 int val;
1182 /* The label table. */
1183 static const struct prefixentry *labels;
1185 /* Default labels. */
1186 static const struct prefixentry default_labels[] =
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 /* The next two entries differ from RFC 3484. We need to treat
1206 IPv6 site-local addresses special because they are never NATed,
1207 unlike site-locale IPv4 addresses. If this would not happen, on
1208 machines which have only IPv4 and IPv6 site-local addresses, the
1209 sorting would prefer the IPv6 site-local addresses, causing
1210 unnecessary delays when trying to connect to a global IPv6 address
1211 through a site-local IPv6 address. */
1212 { { .in6_u
1213 = { .u6_addr8 = { 0xfe, 0xc0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
1214 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } } },
1215 10, 5 },
1216 { { .in6_u
1217 = { .u6_addr8 = { 0xfc, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
1218 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } } },
1219 7, 6 },
1220 { { .in6_u
1221 = { .u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
1222 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } } },
1223 0, 1 }
1227 /* The precedence table. */
1228 static const struct prefixentry *precedence;
1230 /* The default precedences. */
1231 static const struct prefixentry default_precedence[] =
1233 /* See RFC 3484 for the details. */
1234 { { .in6_u
1235 = { .u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
1236 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01 } } },
1237 128, 50 },
1238 { { .in6_u
1239 = { .u6_addr8 = { 0x20, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
1240 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } } },
1241 16, 30 },
1242 { { .in6_u
1243 = { .u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
1244 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } } },
1245 96, 20 },
1246 { { .in6_u
1247 = { .u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
1248 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00 } } },
1249 96, 10 },
1250 { { .in6_u
1251 = { .u6_addr8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
1252 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 } } },
1253 0, 40 }
1257 static int
1258 match_prefix (const struct sockaddr_storage *ss,
1259 const struct prefixentry *list, int default_val)
1261 int idx;
1262 struct sockaddr_in6 in6_mem;
1263 const struct sockaddr_in6 *in6;
1265 if (ss->ss_family == PF_INET6)
1266 in6 = (const struct sockaddr_in6 *) ss;
1267 else if (ss->ss_family == PF_INET)
1269 const struct sockaddr_in *in = (const struct sockaddr_in *) ss;
1271 /* Convert to IPv6 address. */
1272 in6_mem.sin6_family = PF_INET6;
1273 in6_mem.sin6_port = in->sin_port;
1274 in6_mem.sin6_flowinfo = 0;
1275 if (in->sin_addr.s_addr == htonl (0x7f000001))
1276 in6_mem.sin6_addr = (struct in6_addr) IN6ADDR_LOOPBACK_INIT;
1277 else
1279 /* Construct a V4-to-6 mapped address. */
1280 memset (&in6_mem.sin6_addr, '\0', sizeof (in6_mem.sin6_addr));
1281 in6_mem.sin6_addr.s6_addr16[5] = 0xffff;
1282 in6_mem.sin6_addr.s6_addr32[3] = in->sin_addr.s_addr;
1283 in6_mem.sin6_scope_id = 0;
1286 in6 = &in6_mem;
1288 else
1289 return default_val;
1291 for (idx = 0; ; ++idx)
1293 unsigned int bits = list[idx].bits;
1294 const uint8_t *mask = list[idx].prefix.s6_addr;
1295 const uint8_t *val = in6->sin6_addr.s6_addr;
1297 while (bits >= 8)
1299 if (*mask != *val)
1300 break;
1302 ++mask;
1303 ++val;
1304 bits -= 8;
1307 if (bits < 8)
1309 if ((*mask & (0xff00 >> bits)) == (*val & (0xff00 >> bits)))
1310 /* Match! */
1311 break;
1315 return list[idx].val;
1319 static int
1320 get_label (const struct sockaddr_storage *ss)
1322 /* XXX What is a good default value? */
1323 return match_prefix (ss, labels, INT_MAX);
1327 static int
1328 get_precedence (const struct sockaddr_storage *ss)
1330 /* XXX What is a good default value? */
1331 return match_prefix (ss, precedence, 0);
1335 /* Find last bit set in a word. */
1336 static int
1337 fls (uint32_t a)
1339 uint32_t mask;
1340 int n = 0;
1341 for (n = 0, mask = 1 << 31; n < 32; mask >>= 1, ++n)
1342 if ((a & mask) != 0)
1343 break;
1344 return n;
1348 static int
1349 rfc3484_sort (const void *p1, const void *p2)
1351 const struct sort_result *a1 = (const struct sort_result *) p1;
1352 const struct sort_result *a2 = (const struct sort_result *) p2;
1354 /* Rule 1: Avoid unusable destinations.
1355 We have the got_source_addr flag set if the destination is reachable. */
1356 if (a1->got_source_addr && ! a2->got_source_addr)
1357 return -1;
1358 if (! a1->got_source_addr && a2->got_source_addr)
1359 return 1;
1362 /* Rule 2: Prefer matching scope. Only interesting if both
1363 destination addresses are IPv6. */
1364 int a1_dst_scope
1365 = get_scope ((struct sockaddr_storage *) a1->dest_addr->ai_addr);
1367 int a2_dst_scope
1368 = get_scope ((struct sockaddr_storage *) a2->dest_addr->ai_addr);
1370 if (a1->got_source_addr)
1372 int a1_src_scope = get_scope (&a1->source_addr);
1373 int a2_src_scope = get_scope (&a2->source_addr);
1375 if (a1_dst_scope == a1_src_scope && a2_dst_scope != a2_src_scope)
1376 return -1;
1377 if (a1_dst_scope != a1_src_scope && a2_dst_scope == a2_src_scope)
1378 return 1;
1382 /* Rule 3: Avoid deprecated addresses. */
1383 if (a1->got_source_addr)
1385 if (!(a1->source_addr_flags & in6ai_deprecated)
1386 && (a2->source_addr_flags & in6ai_deprecated))
1387 return -1;
1388 if ((a1->source_addr_flags & in6ai_deprecated)
1389 && !(a2->source_addr_flags & in6ai_deprecated))
1390 return 1;
1393 /* Rule 4: Prefer home addresses. */
1394 if (a1->got_source_addr)
1396 if (!(a1->source_addr_flags & in6ai_homeaddress)
1397 && (a2->source_addr_flags & in6ai_homeaddress))
1398 return 1;
1399 if ((a1->source_addr_flags & in6ai_homeaddress)
1400 && !(a2->source_addr_flags & in6ai_homeaddress))
1401 return -1;
1404 /* Rule 5: Prefer matching label. */
1405 if (a1->got_source_addr)
1407 int a1_dst_label
1408 = get_label ((struct sockaddr_storage *) a1->dest_addr->ai_addr);
1409 int a1_src_label = get_label (&a1->source_addr);
1411 int a2_dst_label
1412 = get_label ((struct sockaddr_storage *) a2->dest_addr->ai_addr);
1413 int a2_src_label = get_label (&a2->source_addr);
1415 if (a1_dst_label == a1_src_label && a2_dst_label != a2_src_label)
1416 return -1;
1417 if (a1_dst_label != a1_src_label && a2_dst_label == a2_src_label)
1418 return 1;
1422 /* Rule 6: Prefer higher precedence. */
1423 int a1_prec
1424 = get_precedence ((struct sockaddr_storage *) a1->dest_addr->ai_addr);
1425 int a2_prec
1426 = get_precedence ((struct sockaddr_storage *) a2->dest_addr->ai_addr);
1428 if (a1_prec > a2_prec)
1429 return -1;
1430 if (a1_prec < a2_prec)
1431 return 1;
1434 /* Rule 7: Prefer native transport. */
1435 if (a1->got_source_addr)
1437 if (!(a1->source_addr_flags & in6ai_temporary)
1438 && (a2->source_addr_flags & in6ai_temporary))
1439 return -1;
1440 if ((a1->source_addr_flags & in6ai_temporary)
1441 && !(a2->source_addr_flags & in6ai_temporary))
1442 return 1;
1444 /* XXX Do we need to check anything beside temporary addresses? */
1448 /* Rule 8: Prefer smaller scope. */
1449 if (a1_dst_scope < a2_dst_scope)
1450 return -1;
1451 if (a1_dst_scope > a2_dst_scope)
1452 return 1;
1455 /* Rule 9: Use longest matching prefix. */
1456 if (a1->got_source_addr
1457 && a1->dest_addr->ai_family == a2->dest_addr->ai_family)
1459 int bit1 = 0;
1460 int bit2 = 0;
1462 if (a1->dest_addr->ai_family == PF_INET)
1464 assert (a1->source_addr.ss_family == PF_INET);
1465 assert (a2->source_addr.ss_family == PF_INET);
1467 struct sockaddr_in *in1_dst;
1468 struct sockaddr_in *in1_src;
1469 struct sockaddr_in *in2_dst;
1470 struct sockaddr_in *in2_src;
1472 in1_dst = (struct sockaddr_in *) a1->dest_addr->ai_addr;
1473 in1_src = (struct sockaddr_in *) &a1->source_addr;
1474 in2_dst = (struct sockaddr_in *) a2->dest_addr->ai_addr;
1475 in2_src = (struct sockaddr_in *) &a2->source_addr;
1477 bit1 = fls (ntohl (in1_dst->sin_addr.s_addr
1478 ^ in1_src->sin_addr.s_addr));
1479 bit2 = fls (ntohl (in2_dst->sin_addr.s_addr
1480 ^ in2_src->sin_addr.s_addr));
1482 else if (a1->dest_addr->ai_family == PF_INET6)
1484 assert (a1->source_addr.ss_family == PF_INET6);
1485 assert (a2->source_addr.ss_family == PF_INET6);
1487 struct sockaddr_in6 *in1_dst;
1488 struct sockaddr_in6 *in1_src;
1489 struct sockaddr_in6 *in2_dst;
1490 struct sockaddr_in6 *in2_src;
1492 in1_dst = (struct sockaddr_in6 *) a1->dest_addr->ai_addr;
1493 in1_src = (struct sockaddr_in6 *) &a1->source_addr;
1494 in2_dst = (struct sockaddr_in6 *) a2->dest_addr->ai_addr;
1495 in2_src = (struct sockaddr_in6 *) &a2->source_addr;
1497 int i;
1498 for (i = 0; i < 4; ++i)
1499 if (in1_dst->sin6_addr.s6_addr32[i]
1500 != in1_src->sin6_addr.s6_addr32[i]
1501 || (in2_dst->sin6_addr.s6_addr32[i]
1502 != in2_src->sin6_addr.s6_addr32[i]))
1503 break;
1505 if (i < 4)
1507 bit1 = fls (ntohl (in1_dst->sin6_addr.s6_addr32[i]
1508 ^ in1_src->sin6_addr.s6_addr32[i]));
1509 bit2 = fls (ntohl (in2_dst->sin6_addr.s6_addr32[i]
1510 ^ in2_src->sin6_addr.s6_addr32[i]));
1514 if (bit1 > bit2)
1515 return -1;
1516 if (bit1 < bit2)
1517 return 1;
1521 /* Rule 10: Otherwise, leave the order unchanged. */
1522 return 0;
1526 static int
1527 in6aicmp (const void *p1, const void *p2)
1529 struct in6addrinfo *a1 = (struct in6addrinfo *) p1;
1530 struct in6addrinfo *a2 = (struct in6addrinfo *) p2;
1532 return memcmp (a1->addr, a2->addr, sizeof (a1->addr));
1536 /* Name of the config file for RFC 3484 sorting (for now). */
1537 #define GAICONF_FNAME "/etc/gai.conf"
1540 /* Nozero if we are supposed to reload the config file automatically
1541 whenever it changed. */
1542 static int gaiconf_reload_flag;
1544 /* Last modification time. */
1545 static struct timespec gaiconf_mtime;
1548 libc_freeres_fn(fini)
1550 if (labels != default_labels)
1552 const struct prefixentry *old = labels;
1553 labels = default_labels;
1554 free ((void *) old);
1557 if (precedence != default_precedence)
1559 const struct prefixentry *old = precedence;
1560 precedence = default_precedence;
1561 free ((void *) old);
1566 struct prefixlist
1568 struct prefixentry entry;
1569 struct prefixlist *next;
1573 static void
1574 free_prefixlist (struct prefixlist *list)
1576 while (list != NULL)
1578 struct prefixlist *oldp = list;
1579 list = list->next;
1580 free (oldp);
1585 static int
1586 prefixcmp (const void *p1, const void *p2)
1588 const struct prefixentry *e1 = (const struct prefixentry *) p1;
1589 const struct prefixentry *e2 = (const struct prefixentry *) p2;
1591 if (e1->bits < e2->bits)
1592 return 1;
1593 if (e1->bits == e2->bits)
1594 return 0;
1595 return -1;
1599 static void
1600 gaiconf_init (void)
1602 struct prefixlist *labellist = NULL;
1603 size_t nlabellist = 0;
1604 bool labellist_nullbits = false;
1605 struct prefixlist *precedencelist = NULL;
1606 size_t nprecedencelist = 0;
1607 bool precedencelist_nullbits = false;
1609 FILE *fp = fopen (GAICONF_FNAME, "rc");
1610 if (fp != NULL)
1612 struct stat64 st;
1613 if (__fxstat64 (_STAT_VER, fileno (fp), &st) != 0)
1615 fclose (fp);
1616 goto no_file;
1619 char *line = NULL;
1620 size_t linelen = 0;
1622 __fsetlocking (fp, FSETLOCKING_BYCALLER);
1624 while (!feof_unlocked (fp))
1626 ssize_t n = __getline (&line, &linelen, fp);
1627 if (n <= 0)
1628 break;
1630 /* Handle comments. No escaping possible so this is easy. */
1631 char *cp = strchr (line, '#');
1632 if (cp != NULL)
1633 *cp = '\0';
1635 cp = line;
1636 while (isspace (*cp))
1637 ++cp;
1639 char *cmd = cp;
1640 while (*cp != '\0' && !isspace (*cp))
1641 ++cp;
1642 size_t cmdlen = cp - cmd;
1644 if (*cp != '\0')
1645 *cp++ = '\0';
1646 while (isspace (*cp))
1647 ++cp;
1649 char *val1 = cp;
1650 while (*cp != '\0' && !isspace (*cp))
1651 ++cp;
1652 size_t val1len = cp - cmd;
1654 /* We always need at least two values. */
1655 if (val1len == 0)
1656 continue;
1658 if (*cp != '\0')
1659 *cp++ = '\0';
1660 while (isspace (*cp))
1661 ++cp;
1663 char *val2 = cp;
1664 while (*cp != '\0' && !isspace (*cp))
1665 ++cp;
1667 /* Ignore the rest of the line. */
1668 *cp = '\0';
1670 struct prefixlist **listp;
1671 size_t *lenp;
1672 bool *nullbitsp;
1673 switch (cmdlen)
1675 case 5:
1676 if (strcmp (cmd, "label") == 0)
1678 struct in6_addr prefix;
1679 unsigned long int bits;
1680 unsigned long int val;
1681 char *endp;
1683 listp = &labellist;
1684 lenp = &nlabellist;
1685 nullbitsp = &labellist_nullbits;
1687 new_elem:
1688 bits = 128;
1689 __set_errno (0);
1690 cp = strchr (val1, '/');
1691 if (cp != NULL)
1692 *cp++ = '\0';
1693 if (inet_pton (AF_INET6, val1, &prefix)
1694 && (cp == NULL
1695 || (bits = strtoul (cp, &endp, 10)) != ULONG_MAX
1696 || errno != ERANGE)
1697 && *endp == '\0'
1698 && bits <= INT_MAX
1699 && ((val = strtoul (val2, &endp, 10)) != ULONG_MAX
1700 || errno != ERANGE)
1701 && *endp == '\0'
1702 && val <= INT_MAX)
1704 struct prefixlist *newp = malloc (sizeof (*newp));
1705 if (newp == NULL)
1707 free (line);
1708 fclose (fp);
1709 goto no_file;
1712 memcpy (&newp->entry.prefix, &prefix, sizeof (prefix));
1713 newp->entry.bits = bits;
1714 newp->entry.val = val;
1715 newp->next = *listp;
1716 *listp = newp;
1717 ++*lenp;
1718 *nullbitsp |= bits == 0;
1721 break;
1723 case 6:
1724 if (strcmp (cmd, "reload") == 0)
1725 gaiconf_reload_flag = strcmp (val1, "yes") == 0;
1726 break;
1728 case 10:
1729 if (strcmp (cmd, "precedence") == 0)
1731 listp = &precedencelist;
1732 lenp = &nprecedencelist;
1733 nullbitsp = &precedencelist_nullbits;
1734 goto new_elem;
1736 break;
1740 free (line);
1742 fclose (fp);
1744 /* Create the array for the labels. */
1745 struct prefixentry *new_labels;
1746 if (nlabellist > 0)
1748 if (!labellist_nullbits)
1749 ++nlabellist;
1750 new_labels = malloc (nlabellist * sizeof (*new_labels));
1751 if (new_labels == NULL)
1752 goto no_file;
1754 int i = nlabellist;
1755 if (!labellist_nullbits)
1757 --i;
1758 memset (&new_labels[i].prefix, '\0', sizeof (struct in6_addr));
1759 new_labels[i].bits = 0;
1760 new_labels[i].val = 1;
1763 struct prefixlist *l = labellist;
1764 while (i-- > 0)
1766 new_labels[i] = l->entry;
1767 l = l->next;
1769 free_prefixlist (labellist);
1771 /* Sort the entries so that the most specific ones are at
1772 the beginning. */
1773 qsort (new_labels, nlabellist, sizeof (*new_labels), prefixcmp);
1775 else
1776 new_labels = (struct prefixentry *) default_labels;
1778 struct prefixentry *new_precedence;
1779 if (nprecedencelist > 0)
1781 if (!precedencelist_nullbits)
1782 ++nprecedencelist;
1783 new_precedence = malloc (nprecedencelist * sizeof (*new_precedence));
1784 if (new_precedence == NULL)
1786 if (new_labels != default_labels)
1787 free (new_labels);
1788 goto no_file;
1791 int i = nprecedencelist;
1792 if (!precedencelist_nullbits)
1794 --i;
1795 memset (&new_precedence[i].prefix, '\0',
1796 sizeof (struct in6_addr));
1797 new_precedence[i].bits = 0;
1798 new_precedence[i].val = 40;
1801 struct prefixlist *l = precedencelist;
1802 while (i-- > 0)
1804 new_precedence[i] = l->entry;
1805 l = l->next;
1807 free_prefixlist (precedencelist);
1809 /* Sort the entries so that the most specific ones are at
1810 the beginning. */
1811 qsort (new_precedence, nprecedencelist, sizeof (*new_labels),
1812 prefixcmp);
1814 else
1815 new_precedence = (struct prefixentry *) default_precedence;
1817 /* Now we are ready to replace the values. */
1818 const struct prefixentry *old = labels;
1819 labels = new_labels;
1820 if (old != default_labels)
1821 free ((void *) old);
1823 old = precedence;
1824 precedence = new_precedence;
1825 if (old != default_precedence)
1826 free ((void *) old);
1828 gaiconf_mtime = st.st_mtim;
1830 else
1832 no_file:
1833 free_prefixlist (labellist);
1834 free_prefixlist (precedencelist);
1836 /* If we previously read the file but it is gone now, free the
1837 old data and use the builtin one. Leave the reload flag
1838 alone. */
1839 fini ();
1844 static void
1845 gaiconf_reload (void)
1847 struct stat64 st;
1848 if (__xstat64 (_STAT_VER, GAICONF_FNAME, &st) != 0
1849 || memcmp (&st.st_mtim, &gaiconf_mtime, sizeof (gaiconf_mtime)) != 0)
1850 gaiconf_init ();
1855 getaddrinfo (const char *name, const char *service,
1856 const struct addrinfo *hints, struct addrinfo **pai)
1858 int i = 0, last_i = 0;
1859 int nresults = 0;
1860 struct addrinfo *p = NULL;
1861 struct gaih_service gaih_service, *pservice;
1862 struct addrinfo local_hints;
1864 if (name != NULL && name[0] == '*' && name[1] == 0)
1865 name = NULL;
1867 if (service != NULL && service[0] == '*' && service[1] == 0)
1868 service = NULL;
1870 if (name == NULL && service == NULL)
1871 return EAI_NONAME;
1873 if (hints == NULL)
1874 hints = &default_hints;
1876 if (hints->ai_flags
1877 & ~(AI_PASSIVE|AI_CANONNAME|AI_NUMERICHOST|AI_ADDRCONFIG|AI_V4MAPPED
1878 #ifdef HAVE_LIBIDN
1879 |AI_IDN|AI_CANONIDN|AI_IDN_ALLOW_UNASSIGNED
1880 |AI_IDN_USE_STD3_ASCII_RULES
1881 #endif
1882 |AI_NUMERICSERV|AI_ALL))
1883 return EAI_BADFLAGS;
1885 if ((hints->ai_flags & AI_CANONNAME) && name == NULL)
1886 return EAI_BADFLAGS;
1888 struct in6addrinfo *in6ai = NULL;
1889 size_t in6ailen;
1890 bool seen_ipv4 = false;
1891 bool seen_ipv6 = false;
1892 /* We might need information about what kind of interfaces are available.
1893 But even if AI_ADDRCONFIG is not used, if the user requested IPv6
1894 addresses we have to know whether an address is deprecated or
1895 temporary. */
1896 if ((hints->ai_flags & AI_ADDRCONFIG) || hints->ai_family == PF_UNSPEC
1897 || hints->ai_family == PF_INET6)
1898 /* Determine whether we have IPv4 or IPv6 interfaces or both. We
1899 cannot cache the results since new interfaces could be added at
1900 any time. */
1901 __check_pf (&seen_ipv4, &seen_ipv6, &in6ai, &in6ailen);
1903 if (hints->ai_flags & AI_ADDRCONFIG)
1905 /* Now make a decision on what we return, if anything. */
1906 if (hints->ai_family == PF_UNSPEC && (seen_ipv4 || seen_ipv6))
1908 /* If we haven't seen both IPv4 and IPv6 interfaces we can
1909 narrow down the search. */
1910 if (! seen_ipv4 || ! seen_ipv6)
1912 local_hints = *hints;
1913 local_hints.ai_family = seen_ipv4 ? PF_INET : PF_INET6;
1914 hints = &local_hints;
1917 else if ((hints->ai_family == PF_INET && ! seen_ipv4)
1918 || (hints->ai_family == PF_INET6 && ! seen_ipv6))
1920 /* We cannot possibly return a valid answer. */
1921 free (in6ai);
1922 return EAI_NONAME;
1926 if (service && service[0])
1928 char *c;
1929 gaih_service.name = service;
1930 gaih_service.num = strtoul (gaih_service.name, &c, 10);
1931 if (*c != '\0')
1933 if (hints->ai_flags & AI_NUMERICSERV)
1935 free (in6ai);
1936 return EAI_NONAME;
1939 gaih_service.num = -1;
1942 pservice = &gaih_service;
1944 else
1945 pservice = NULL;
1947 struct addrinfo **end;
1948 if (pai)
1949 end = &p;
1950 else
1951 end = NULL;
1953 unsigned int naddrs = 0;
1954 #if 0
1955 /* If we would support more protocols than just IPv4 and IPv6 we
1956 would iterate over a table with appropriate callback functions.
1957 Since we currently only handle IPv4 and IPv6 this is not
1958 necessary. */
1959 const struct gaih *g = gaih;
1960 const struct gaih *pg = NULL;
1961 int j = 0;
1962 while (g->gaih)
1964 if (hints->ai_family == g->family || hints->ai_family == AF_UNSPEC)
1966 j++;
1967 if (pg == NULL || pg->gaih != g->gaih)
1969 pg = g;
1970 i = g->gaih (name, pservice, hints, end, &naddrs);
1971 if (i != 0)
1973 /* EAI_NODATA is a more specific result as it says that
1974 we found a result but it is not usable. */
1975 if (last_i != (GAIH_OKIFUNSPEC | -EAI_NODATA))
1976 last_i = i;
1978 if (hints->ai_family == AF_UNSPEC && (i & GAIH_OKIFUNSPEC))
1980 ++g;
1981 continue;
1984 freeaddrinfo (p);
1985 free (in6ai);
1987 return -(i & GAIH_EAI);
1989 if (end)
1990 while (*end)
1992 end = &((*end)->ai_next);
1993 ++nresults;
1997 ++g;
2000 if (j == 0)
2002 free (in6ai);
2003 return EAI_FAMILY;
2005 #else
2006 if (hints->ai_family == AF_UNSPEC || hints->ai_family == AF_INET
2007 || hints->ai_family == AF_INET6)
2009 last_i = gaih_inet (name, pservice, hints, end, &naddrs);
2010 if (last_i != 0)
2012 freeaddrinfo (p);
2013 free (in6ai);
2015 return -(last_i & GAIH_EAI);
2017 if (end)
2018 while (*end)
2020 end = &((*end)->ai_next);
2021 ++nresults;
2024 else
2026 free (in6ai);
2027 return EAI_FAMILY;
2029 #endif
2031 if (naddrs > 1)
2033 /* Read the config file. */
2034 __libc_once_define (static, once);
2035 __typeof (once) old_once = once;
2036 __libc_once (once, gaiconf_init);
2037 if (old_once && gaiconf_reload_flag)
2038 gaiconf_reload ();
2040 /* Sort results according to RFC 3484. */
2041 struct sort_result results[nresults];
2042 struct addrinfo *q;
2043 struct addrinfo *last = NULL;
2044 char *canonname = NULL;
2046 /* If we have information about deprecated and temporary address
2047 sort the array now. */
2048 if (in6ai != NULL)
2049 qsort (in6ai, in6ailen, sizeof (*in6ai), in6aicmp);
2051 for (i = 0, q = p; q != NULL; ++i, last = q, q = q->ai_next)
2053 results[i].dest_addr = q;
2054 results[i].got_source_addr = false;
2056 /* If we just looked up the address for a different
2057 protocol, reuse the result. */
2058 if (last != NULL && last->ai_addrlen == q->ai_addrlen
2059 && memcmp (last->ai_addr, q->ai_addr, q->ai_addrlen) == 0)
2061 memcpy (&results[i].source_addr, &results[i - 1].source_addr,
2062 results[i - 1].source_addr_len);
2063 results[i].source_addr_len = results[i - 1].source_addr_len;
2064 results[i].got_source_addr = results[i - 1].got_source_addr;
2065 results[i].source_addr_flags = results[i - 1].source_addr_flags;
2067 else
2069 results[i].source_addr_flags = 0;
2071 /* We overwrite the type with SOCK_DGRAM since we do not
2072 want connect() to connect to the other side. If we
2073 cannot determine the source address remember this
2074 fact. */
2075 int fd = __socket (q->ai_family, SOCK_DGRAM, IPPROTO_IP);
2076 socklen_t sl = sizeof (results[i].source_addr);
2077 if (fd != -1
2078 && __connect (fd, q->ai_addr, q->ai_addrlen) == 0
2079 && __getsockname (fd,
2080 (struct sockaddr *) &results[i].source_addr,
2081 &sl) == 0)
2083 results[i].source_addr_len = sl;
2084 results[i].got_source_addr = true;
2086 if (q->ai_family == PF_INET6 && in6ai != NULL)
2088 /* See whether the source address is the list of
2089 deprecated or temporary addresses. */
2090 struct in6addrinfo tmp;
2091 struct sockaddr_in6 *sin6p
2092 = (struct sockaddr_in6 *) &results[i].source_addr;
2093 memcpy (tmp.addr, &sin6p->sin6_addr, IN6ADDRSZ);
2095 struct in6addrinfo *found
2096 = bsearch (&tmp, in6ai, in6ailen, sizeof (*in6ai),
2097 in6aicmp);
2098 if (found != NULL)
2099 results[i].source_addr_flags = found->flags;
2102 else
2103 /* Just make sure that if we have to process the same
2104 address again we do not copy any memory. */
2105 results[i].source_addr_len = 0;
2107 if (fd != -1)
2108 close_not_cancel_no_status (fd);
2111 /* Remember the canonical name. */
2112 if (q->ai_canonname != NULL)
2114 assert (canonname == NULL);
2115 canonname = q->ai_canonname;
2116 q->ai_canonname = NULL;
2120 /* We got all the source addresses we can get, now sort using
2121 the information. */
2122 qsort (results, nresults, sizeof (results[0]), rfc3484_sort);
2124 /* Queue the results up as they come out of sorting. */
2125 q = p = results[0].dest_addr;
2126 for (i = 1; i < nresults; ++i)
2127 q = q->ai_next = results[i].dest_addr;
2128 q->ai_next = NULL;
2130 /* Fill in the canonical name into the new first entry. */
2131 p->ai_canonname = canonname;
2134 free (in6ai);
2136 if (p)
2138 *pai = p;
2139 return 0;
2142 if (pai == NULL && last_i == 0)
2143 return 0;
2145 return last_i ? -(last_i & GAIH_EAI) : EAI_NONAME;
2147 libc_hidden_def (getaddrinfo)
2149 static_link_warning (getaddrinfo)
2151 void
2152 freeaddrinfo (struct addrinfo *ai)
2154 struct addrinfo *p;
2156 while (ai != NULL)
2158 p = ai;
2159 ai = ai->ai_next;
2160 free (p->ai_canonname);
2161 free (p);
2164 libc_hidden_def (freeaddrinfo)