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getaddrinfo.c

Last change on this file was 444, checked in by satin@…, 7 years ago
add newlib,libalmos-mkh, restructure shared_syscalls.h and mini-libc
File size: 44.4 KB

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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 <alloca.h>
39	#include <sys/types.h>
40	#include <assert.h>
41	#include <errno.h>
42	#include <ifaddrs.h>
43	#include <netdb.h>
44	#include <resolv.h>
45	#include <stdbool.h>
46	#include <stdio.h>
47	#include <stdlib.h>
48	#include <string.h>
49	#include <unistd.h>
50	#include <arpa/inet.h>
51	#include <sys/socket.h>
52	#include <netinet/in.h>
53	#include <sys/un.h>
54	#include <sys/utsname.h>
55	#include <net/if.h>
56	#include <nsswitch.h>
57	#include <not-cancel.h>
58	#include <nscd/nscd-client.h>
59	#include <nscd/nscd_proto.h>
60	#include <limits.h>
61	#include "local.h"
62
63	#ifdef HAVE_LIBIDN
64	extern int __idna_to_ascii_lz (const char input, char *output, int flags);
65	extern int __idna_to_unicode_lzlz (const char input, char *output,
66	int flags);
67	# include <libidn/idna.h>
68	#endif
69
70	#define GAIH_OKIFUNSPEC 0x0100
71	#define GAIH_EAI ~(GAIH_OKIFUNSPEC)
72
73	#ifndef UNIX_PATH_MAX
74	#define UNIX_PATH_MAX 108
75	#endif
76
77	struct gaih_service
78	{
79	const char *name;
80	int num;
81	};
82
83	struct gaih_servtuple
84	{
85	struct gaih_servtuple *next;
86	int socktype;
87	int protocol;
88	int port;
89	};
90
91	static const struct gaih_servtuple nullserv;
92
93	struct gaih_addrtuple
94	{
95	struct gaih_addrtuple *next;
96	char *name;
97	int family;
98	uint32_t addr[4];
99	uint32_t scopeid;
100	};
101
102	struct gaih_typeproto
103	{
104	int socktype;
105	int protocol;
106	char name[4];
107	int protoflag;
108	};
109
110	/* Values for `protoflag'. */
111	#define GAI_PROTO_NOSERVICE 1
112	#define GAI_PROTO_PROTOANY 2
113
114	static const struct gaih_typeproto gaih_inet_typeproto[] =
115	{
116	{ 0, 0, "", 0 },
117	{ SOCK_STREAM, IPPROTO_TCP, "tcp", 0 },
118	{ SOCK_DGRAM, IPPROTO_UDP, "udp", 0 },
119	{ SOCK_RAW, 0, "raw", GAI_PROTO_PROTOANY\|GAI_PROTO_NOSERVICE },
120	{ 0, 0, "", 0 }
121	};
122
123	struct gaih
124	{
125	int family;
126	int (gaih)(const char name, const struct gaih_service *service,
127	const struct addrinfo req, struct addrinfo *pai);
128	};
129
130	static const struct addrinfo default_hints =
131	{
132	.ai_flags = AI_DEFAULT,
133	.ai_family = PF_UNSPEC,
134	.ai_socktype = 0,
135	.ai_protocol = 0,
136	.ai_addrlen = 0,
137	.ai_addr = NULL,
138	.ai_canonname = NULL,
139	.ai_next = NULL
140	};
141
142	#define s6_addr32 __u6_addr.__u6_addr32
143
144	#if 0
145	/* Using Unix sockets this way is a security risk. */
146	static int
147	gaih_local (const char name, const struct gaih_service service,
148	const struct addrinfo req, struct addrinfo *pai)
149	{
150	struct utsname utsname;
151
152	if ((name != NULL) && (req->ai_flags & AI_NUMERICHOST))
153	return GAIH_OKIFUNSPEC \| -EAI_NONAME;
154
155	if ((name != NULL) \|\| (req->ai_flags & AI_CANONNAME))
156	if (uname (&utsname) < 0)
157	return -EAI_SYSTEM;
158
159	if (name != NULL)
160	{
161	if (strcmp(name, "localhost") &&
162	strcmp(name, "local") &&
163	strcmp(name, "unix") &&
164	strcmp(name, utsname.nodename))
165	return GAIH_OKIFUNSPEC \| -EAI_NONAME;
166	}
167
168	if (req->ai_protocol \|\| req->ai_socktype)
169	{
170	const struct gaih_typeproto *tp = gaih_inet_typeproto + 1;
171
172	while (tp->name[0]
173	&& ((tp->protoflag & GAI_PROTO_NOSERVICE) != 0
174	\|\| (req->ai_socktype != 0 && req->ai_socktype != tp->socktype)
175	\|\| (req->ai_protocol != 0
176	&& !(tp->protoflag & GAI_PROTO_PROTOANY)
177	&& req->ai_protocol != tp->protocol)))
178	++tp;
179
180	if (! tp->name[0])
181	{
182	if (req->ai_socktype)
183	return (GAIH_OKIFUNSPEC \| -EAI_SOCKTYPE);
184	else
185	return (GAIH_OKIFUNSPEC \| -EAI_SERVICE);
186	}
187	}
188
189	*pai = malloc (sizeof (struct addrinfo) + sizeof (struct sockaddr_un)
190	+ ((req->ai_flags & AI_CANONNAME)
191	? (strlen(utsname.nodename) + 1): 0));
192	if (*pai == NULL)
193	return -EAI_MEMORY;
194
195	(*pai)->ai_next = NULL;
196	(*pai)->ai_flags = req->ai_flags;
197	(*pai)->ai_family = AF_LOCAL;
198	(*pai)->ai_socktype = req->ai_socktype ? req->ai_socktype : SOCK_STREAM;
199	(*pai)->ai_protocol = req->ai_protocol;
200	(*pai)->ai_addrlen = sizeof (struct sockaddr_un);
201	(pai)->ai_addr = (void ) (*pai) + sizeof (struct addrinfo);
202
203	#if SALEN
204	((struct sockaddr_un ) (pai)->ai_addr)->sun_len =
205	sizeof (struct sockaddr_un);
206	#endif /* SALEN */
207
208	((struct sockaddr_un )(pai)->ai_addr)->sun_family = AF_LOCAL;
209	memset(((struct sockaddr_un )(pai)->ai_addr)->sun_path, 0, UNIX_PATH_MAX);
210
211	if (service)
212	{
213	struct sockaddr_un sunp = (struct sockaddr_un ) (*pai)->ai_addr;
214
215	if (strchr (service->name, '/') != NULL)
216	{
217	if (strlen (service->name) >= sizeof (sunp->sun_path))
218	return GAIH_OKIFUNSPEC \| -EAI_SERVICE;
219
220	strcpy (sunp->sun_path, service->name);
221	}
222	else
223	{
224	if (strlen (P_tmpdir "/") + 1 + strlen (service->name) >=
225	sizeof (sunp->sun_path))
226	return GAIH_OKIFUNSPEC \| -EAI_SERVICE;
227
228	__stpcpy (__stpcpy (sunp->sun_path, P_tmpdir "/"), service->name);
229	}
230	}
231	else
232	{
233	/* This is a dangerous use of the interface since there is a time
234	window between the test for the file and the actual creation
235	(done by the caller) in which a file with the same name could
236	be created. */
237	char buf = ((struct sockaddr_un ) (*pai)->ai_addr)->sun_path;
238
239	if (__builtin_expect (__path_search (buf, L_tmpnam, NULL, NULL, 0),
240	0) != 0
241	\|\| __builtin_expect (__gen_tempname (buf, __GT_NOCREATE), 0) != 0)
242	return -EAI_SYSTEM;
243	}
244
245	if (req->ai_flags & AI_CANONNAME)
246	(pai)->ai_canonname = strcpy ((char ) *pai + sizeof (struct addrinfo)
247	+ sizeof (struct sockaddr_un),
248	utsname.nodename);
249	else
250	(*pai)->ai_canonname = NULL;
251	return 0;
252	}
253	#endif /* 0 */
254
255	static int
256	gaih_inet_serv (const char servicename, const struct gaih_typeproto tp,
257	const struct addrinfo req, struct gaih_servtuple st)
258	{
259	struct servent *s;
260	size_t tmpbuflen = 1024;
261	struct servent ts;
262	char *tmpbuf;
263	int r;
264
265	do
266	{
267	tmpbuf = alloca (tmpbuflen);
268
269	r = __getservbyname_r (servicename, tp->name, &ts, tmpbuf, tmpbuflen,
270	&s);
271	if (r != 0 \|\| s == NULL)
272	{
273	if (r == ERANGE)
274	tmpbuflen *= 2;
275	else
276	return GAIH_OKIFUNSPEC \| -EAI_SERVICE;
277	}
278	}
279	while (r);
280
281	st->next = NULL;
282	st->socktype = tp->socktype;
283	st->protocol = ((tp->protoflag & GAI_PROTO_PROTOANY)
284	? req->ai_protocol : tp->protocol);
285	st->port = s->s_port;
286
287	return 0;
288	}
289
290	#define gethosts(_family, _type) \
291	{ \
292	int i; \
293	int herrno; \
294	struct hostent th; \
295	struct hostent *h; \
296	char *localcanon = NULL; \
297	no_data = 0; \
298	while (1) { \
299	rc = 0; \
300	status = DL_CALL_FCT (fct, (name, _family, &th, tmpbuf, tmpbuflen, \
301	&rc, &herrno, NULL, &localcanon)); \
302	if (rc != ERANGE \|\| herrno != NETDB_INTERNAL) \
303	break; \
304	tmpbuf = extend_alloca (tmpbuf, tmpbuflen, 2 * tmpbuflen); \
305	} \
306	if (status == NSS_STATUS_SUCCESS && rc == 0) \
307	h = &th; \
308	else \
309	h = NULL; \
310	if (rc != 0) \
311	{ \
312	if (herrno == NETDB_INTERNAL) \
313	{ \
314	h_errno = (herrno); \
315	return -EAI_SYSTEM; \
316	} \
317	if (herrno == TRY_AGAIN) \
318	no_data = EAI_AGAIN; \
319	else \
320	no_data = herrno == NO_DATA; \
321	} \
322	else if (h != NULL) \
323	{ \
324	for (i = 0; h->h_addr_list[i]; i++) \
325	{ \
326	if (*pat == NULL) \
327	{ \
328	*pat = alloca (sizeof (struct gaih_addrtuple)); \
329	(*pat)->scopeid = 0; \
330	} \
331	uint32_t addr = (pat)->addr; \
332	(*pat)->next = NULL; \
333	if (i == 0) \
334	{ \
335	(*pat)->name = alloca (strlen (h->h_name) + 1); \
336	strcpy ((*pat)->name, h->h_name); \
337	} \
338	else \
339	(*pat)->name = NULL; \
340	if (_family == AF_INET && req->ai_family == AF_INET6) \
341	{ \
342	(*pat)->family = AF_INET6; \
343	addr[3] = (uint32_t ) h->h_addr_list[i]; \
344	addr[2] = htonl (0xffff); \
345	addr[1] = 0; \
346	addr[0] = 0; \
347	} \
348	else \
349	{ \
350	(*pat)->family = _family; \
351	memcpy (addr, h->h_addr_list[i], sizeof(_type)); \
352	} \
353	pat = &((*pat)->next); \
354	} \
355	\
356	if (localcanon != NULL && canon == NULL) \
357	{ \
358	canon = alloca (strlen (localcanon) + 1); \
359	strcpy (canon, localcanon); \
360	} \
361	\
362	if (_family == AF_INET6 && i > 0) \
363	got_ipv6 = true; \
364	} \
365	}
366
367
368	typedef enum nss_status (*nss_gethostbyname3_r)
369	(const char name, int af, struct hostent host,
370	char buffer, size_t buflen, int errnop,
371	int h_errnop, int32_t ttlp, char **canonp);
372	typedef enum nss_status (*nss_getcanonname_r)
373	(const char name, char buffer, size_t buflen, char **result,
374	int errnop, int h_errnop);
375	extern service_user *__nss_hosts_database attribute_hidden;
376
377	static int
378	gaih_inet (const char name, const struct gaih_service service,
379	const struct addrinfo req, struct addrinfo *pai)
380	{
381	const struct gaih_typeproto *tp = gaih_inet_typeproto;
382	struct gaih_servtuple st = (struct gaih_servtuple ) &nullserv;
383	struct gaih_addrtuple *at = NULL;
384	int rc;
385	bool got_ipv6 = false;
386	const char *canon = NULL;
387	const char *orig_name = name;
388
389	if (req->ai_protocol \|\| req->ai_socktype)
390	{
391	++tp;
392
393	while (tp->name[0]
394	&& ((req->ai_socktype != 0 && req->ai_socktype != tp->socktype)
395	\|\| (req->ai_protocol != 0
396	&& !(tp->protoflag & GAI_PROTO_PROTOANY)
397	&& req->ai_protocol != tp->protocol)))
398	++tp;
399
400	if (! tp->name[0])
401	{
402	if (req->ai_socktype)
403	return (GAIH_OKIFUNSPEC \| -EAI_SOCKTYPE);
404	else
405	return (GAIH_OKIFUNSPEC \| -EAI_SERVICE);
406	}
407	}
408
409	if (service != NULL)
410	{
411	if ((tp->protoflag & GAI_PROTO_NOSERVICE) != 0)
412	return (GAIH_OKIFUNSPEC \| -EAI_SERVICE);
413
414	if (service->num < 0)
415	{
416	if (tp->name[0])
417	{
418	st = (struct gaih_servtuple *)
419	alloca (sizeof (struct gaih_servtuple));
420
421	if ((rc = gaih_inet_serv (service->name, tp, req, st)))
422	return rc;
423	}
424	else
425	{
426	struct gaih_servtuple **pst = &st;
427	for (tp++; tp->name[0]; tp++)
428	{
429	struct gaih_servtuple *newp;
430
431	if ((tp->protoflag & GAI_PROTO_NOSERVICE) != 0)
432	continue;
433
434	if (req->ai_socktype != 0
435	&& req->ai_socktype != tp->socktype)
436	continue;
437	if (req->ai_protocol != 0
438	&& !(tp->protoflag & GAI_PROTO_PROTOANY)
439	&& req->ai_protocol != tp->protocol)
440	continue;
441
442	newp = (struct gaih_servtuple *)
443	alloca (sizeof (struct gaih_servtuple));
444
445	if ((rc = gaih_inet_serv (service->name, tp, req, newp)))
446	{
447	if (rc & GAIH_OKIFUNSPEC)
448	continue;
449	return rc;
450	}
451
452	*pst = newp;
453	pst = &(newp->next);
454	}
455	if (st == (struct gaih_servtuple *) &nullserv)
456	return (GAIH_OKIFUNSPEC \| -EAI_SERVICE);
457	}
458	}
459	else
460	{
461	if (req->ai_socktype \|\| req->ai_protocol)
462	{
463	st = alloca (sizeof (struct gaih_servtuple));
464	st->next = NULL;
465	st->socktype = tp->socktype;
466	st->protocol = ((tp->protoflag & GAI_PROTO_PROTOANY)
467	? req->ai_protocol : tp->protocol);
468	st->port = htons (service->num);
469	}
470	else
471	{
472	/* Neither socket type nor protocol is set. Return all
473	socket types we know about. */
474	struct gaih_servtuple **lastp = &st;
475	for (tp = gaih_inet_typeproto + 1; tp->name[0]; ++tp)
476	if ((tp->protoflag & GAI_PROTO_NOSERVICE) == 0)
477	{
478	struct gaih_servtuple *newp;
479
480	newp = alloca (sizeof (struct gaih_servtuple));
481	newp->next = NULL;
482	newp->socktype = tp->socktype;
483	newp->protocol = tp->protocol;
484	newp->port = htons (service->num);
485
486	*lastp = newp;
487	lastp = &newp->next;
488	}
489	}
490	}
491	}
492	else if (req->ai_socktype \|\| req->ai_protocol)
493	{
494	st = alloca (sizeof (struct gaih_servtuple));
495	st->next = NULL;
496	st->socktype = tp->socktype;
497	st->protocol = ((tp->protoflag & GAI_PROTO_PROTOANY)
498	? req->ai_protocol : tp->protocol);
499	st->port = 0;
500	}
501	else
502	{
503	/* Neither socket type nor protocol is set. Return all socket types
504	we know about. */
505	struct gaih_servtuple **lastp = &st;
506	for (++tp; tp->name[0]; ++tp)
507	{
508	struct gaih_servtuple *newp;
509
510	newp = alloca (sizeof (struct gaih_servtuple));
511	newp->next = NULL;
512	newp->socktype = tp->socktype;
513	newp->protocol = tp->protocol;
514	newp->port = 0;
515
516	*lastp = newp;
517	lastp = &newp->next;
518	}
519	}
520
521	if (name != NULL)
522	{
523	at = alloca (sizeof (struct gaih_addrtuple));
524
525	at->family = AF_UNSPEC;
526	at->scopeid = 0;
527	at->next = NULL;
528
529	#ifdef HAVE_LIBIDN
530	if (req->ai_flags & AI_IDN)
531	{
532	int idn_flags = 0;
533	if (req->ai_flags & AI_IDN_ALLOW_UNASSIGNED)
534	idn_flags \|= IDNA_ALLOW_UNASSIGNED;
535	if (req->ai_flags & AI_IDN_USE_STD3_ASCII_RULES)
536	idn_flags \|= IDNA_USE_STD3_ASCII_RULES;
537
538	char *p = NULL;
539	rc = __idna_to_ascii_lz (name, &p, idn_flags);
540	if (rc != IDNA_SUCCESS)
541	{
542	if (rc == IDNA_MALLOC_ERROR)
543	return -EAI_MEMORY;
544	if (rc == IDNA_DLOPEN_ERROR)
545	return -EAI_SYSTEM;
546	return -EAI_IDN_ENCODE;
547	}
548	/* In case the output string is the same as the input string
549	no new string has been allocated. */
550	if (p != name)
551	{
552	name = alloca (strlen (p) + 1);
553	strcpy (name, p);
554	free (p);
555	}
556	}
557	#endif
558
559	if (inet_aton (name, (struct in_addr *) at->addr) != 0)
560	{
561	if (req->ai_family == AF_UNSPEC \|\| req->ai_family == AF_INET)
562	at->family = AF_INET;
563	else if (req->ai_family == AF_INET6 && req->ai_flags & AI_V4MAPPED)
564	{
565	at->addr[3] = at->addr[0];
566	at->addr[2] = htonl (0xffff);
567	at->addr[1] = 0;
568	at->addr[0] = 0;
569	at->family = AF_INET6;
570	}
571	else
572	return -EAI_ADDRFAMILY;
573
574	dupname:
575	if (req->ai_flags & AI_CANONNAME)
576	{
577	canon = strdup (name);
578	if (canon == NULL)
579	return -EAI_MEMORY;
580	}
581	}
582
583	if (at->family == AF_UNSPEC)
584	{
585	char *scope_delim;
586	char *namebuf = alloca (strlen (name) + 1);
587	strcpy (namebuf, name);
588
589	scope_delim = strchr (namebuf, SCOPE_DELIMITER);
590	if (scope_delim != NULL)
591	*scope_delim = '\0';
592
593	if (inet_pton (AF_INET6, namebuf, at->addr) > 0)
594	{
595	if (req->ai_family == AF_UNSPEC \|\| req->ai_family == AF_INET6)
596	at->family = AF_INET6;
597	else if (req->ai_family == AF_INET
598	&& IN6_IS_ADDR_V4MAPPED ((struct in6_addr *)at->addr))
599	{
600	at->addr[0] = at->addr[3];
601	at->family = AF_INET;
602	}
603	else
604	return -EAI_ADDRFAMILY;
605
606	if (scope_delim != NULL)
607	{
608	int try_numericscope = 0;
609	if (IN6_IS_ADDR_LINKLOCAL ((struct in6_addr *)at->addr)
610	\|\| IN6_IS_ADDR_MC_LINKLOCAL ((struct in6_addr *)at->addr))
611	{
612	at->scopeid = if_nametoindex (scope_delim + 1);
613	if (at->scopeid == 0)
614	try_numericscope = 1;
615	}
616	else
617	try_numericscope = 1;
618
619	if (try_numericscope != 0)
620	{
621	char *end;
622	assert (sizeof (uint32_t) <= sizeof (unsigned long));
623	at->scopeid = (uint32_t) strtoul (scope_delim + 1, &end,
624	10);
625	if (*end != '\0')
626	return GAIH_OKIFUNSPEC \| -EAI_NONAME;
627	}
628	}
629
630	goto dupname;
631	}
632	}
633
634	if (at->family == AF_UNSPEC && (req->ai_flags & AI_NUMERICHOST) == 0)
635	{
636	struct gaih_addrtuple **pat = &at;
637	int no_data = 0;
638	int no_inet6_data = 0;
639	service_user *nip = NULL;
640	enum nss_status inet6_status = NSS_STATUS_UNAVAIL;
641	enum nss_status status = NSS_STATUS_UNAVAIL;
642	int no_more;
643	int old_res_options;
644
645	/* If we do not have to look for IPv4 and IPv6 together, use
646	the simple, old functions. */
647	if (req->ai_family == AF_INET \|\| req->ai_family == AF_INET6)
648	{
649	int family = req->ai_family;
650	size_t tmpbuflen = 512;
651	char *tmpbuf = alloca (tmpbuflen);
652	int rc;
653	struct hostent th;
654	struct hostent *h;
655	int herrno;
656
657	simple_again:
658	while (1)
659	{
660	rc = __gethostbyname2_r (name, family, &th, tmpbuf,
661	tmpbuflen, &h, &herrno);
662	if (rc != ERANGE \|\| herrno != NETDB_INTERNAL)
663	break;
664	tmpbuf = extend_alloca (tmpbuf, tmpbuflen, 2 * tmpbuflen);
665	}
666
667	if (rc == 0)
668	{
669	if (h == NULL)
670	{
671	if (req->ai_family == AF_INET6
672	&& (req->ai_flags & AI_V4MAPPED)
673	&& family == AF_INET6)
674	{
675	/* Try again, this time looking for IPv4
676	addresses. */
677	family = AF_INET;
678	goto simple_again;
679	}
680	}
681	else
682	{
683	/* We found data, now convert it into the list. */
684	int i = 0;
685	for (i = 0; h->h_addr_list[i]; ++i)
686	{
687	if (*pat == NULL)
688	{
689	*pat = alloca (sizeof (struct gaih_addrtuple));
690	(*pat)->scopeid = 0;
691	}
692	(*pat)->next = NULL;
693	(*pat)->family = req->ai_family;
694	if (family == req->ai_family)
695	memcpy ((*pat)->addr, h->h_addr_list[i],
696	h->h_length);
697	else
698	{
699	int32_t addr = (uint32_t ) (*pat)->addr;
700	addr[3] = (uint32_t ) h->h_addr_list[i];
701	addr[2] = htonl (0xffff);
702	addr[1] = 0;
703	addr[0] = 0;
704	}
705	pat = &((*pat)->next);
706	}
707	}
708	}
709	else
710	{
711	if (herrno == NETDB_INTERNAL)
712	{
713	h_errno = (herrno);
714	return -EAI_SYSTEM;
715	}
716	if (herrno == TRY_AGAIN)
717	{
718	return -EAI_AGAIN;
719	}
720	/* We made requests but they turned out no data.
721	The name is known, though. */
722	return (GAIH_OKIFUNSPEC \| -EAI_NODATA);
723	}
724
725	goto process_list;
726	}
727
728	#ifdef USE_NSCD
729	if (__nss_not_use_nscd_hosts > 0
730	&& ++__nss_not_use_nscd_hosts > NSS_NSCD_RETRY)
731	__nss_not_use_nscd_hosts = 0;
732
733	if (!__nss_not_use_nscd_hosts)
734	{
735	/* Try to use nscd. */
736	struct nscd_ai_result *air = NULL;
737	int herrno;
738	int err = __nscd_getai (name, &air, &herrno);
739	if (air != NULL)
740	{
741	/* Transform into gaih_addrtuple list. */
742	bool added_canon = (req->ai_flags & AI_CANONNAME) == 0;
743	char *addrs = air->addrs;
744
745	for (int i = 0; i < air->naddrs; ++i)
746	{
747	socklen_t size = (air->family[i] == AF_INET
748	? INADDRSZ : IN6ADDRSZ);
749	if (*pat == NULL)
750	{
751	*pat = alloca (sizeof (struct gaih_addrtuple));
752	(*pat)->scopeid = 0;
753	}
754	uint32_t pataddr = (pat)->addr;
755	(*pat)->next = NULL;
756	if (added_canon \|\| air->canon == NULL)
757	(*pat)->name = NULL;
758	else {
759	canon = (*pat)->name = alloca (strlen (air->canon) + 1);
760	strcpy (canon, air->canon);
761	}
762
763	if (air->family[i] == AF_INET
764	&& req->ai_family == AF_INET6
765	&& (req->ai_flags & AI_V4MAPPED))
766	{
767	(*pat)->family = AF_INET6;
768	pataddr[3] = (uint32_t ) addrs;
769	pataddr[2] = htonl (0xffff);
770	pataddr[1] = 0;
771	pataddr[0] = 0;
772	pat = &((*pat)->next);
773	added_canon = true;
774	}
775	else if (req->ai_family == AF_UNSPEC
776	\|\| air->family[i] == req->ai_family)
777	{
778	(*pat)->family = air->family[i];
779	memcpy (pataddr, addrs, size);
780	pat = &((*pat)->next);
781	added_canon = true;
782	if (air->family[i] == AF_INET6)
783	got_ipv6 = true;
784	}
785	addrs += size;
786	}
787
788	free (air);
789
790	if (at->family == AF_UNSPEC)
791	return (GAIH_OKIFUNSPEC \| -EAI_NONAME);
792
793	goto process_list;
794	}
795	else if (err != 0 && __nss_not_use_nscd_hosts == 0)
796	{
797	if (herrno == NETDB_INTERNAL && errno == ENOMEM)
798	return -EAI_MEMORY;
799	if (herrno == TRY_AGAIN)
800	return -EAI_AGAIN;
801	return -EAI_SYSTEM;
802	}
803	}
804	#endif
805
806	if (__nss_hosts_database != NULL)
807	{
808	no_more = 0;
809	nip = __nss_hosts_database;
810	}
811	else
812	no_more = __nss_database_lookup ("hosts", NULL,
813	"dns [!UNAVAIL=return] files",
814	&nip);
815
816	if (__res_maybe_init (&_res, 0) == -1)
817	no_more = 1;
818
819	/* If we are looking for both IPv4 and IPv6 address we don't
820	want the lookup functions to automatically promote IPv4
821	addresses to IPv6 addresses. Currently this is decided
822	by setting the RES_USE_INET6 bit in _res.options. */
823	old_res_options = _res.options;
824	_res.options &= ~RES_USE_INET6;
825
826	size_t tmpbuflen = 512;
827	char *tmpbuf = alloca (tmpbuflen);
828
829	while (!no_more)
830	{
831	nss_gethostbyname3_r fct = NULL;
832	if (req->ai_flags & AI_CANONNAME)
833	/* No need to use this function if we do not look for
834	the canonical name. The function does not exist in
835	all NSS modules and therefore the lookup would
836	often fail. */
837	fct = __nss_lookup_function (nip, "gethostbyname3_r");
838	if (fct == NULL)
839	/* We are cheating here. The gethostbyname2_r function does
840	not have the same interface as gethostbyname3_r but the
841	extra arguments the latter takes are added at the end.
842	So the gethostbyname2_r code will just ignore them. */
843	fct = __nss_lookup_function (nip, "gethostbyname2_r");
844
845	if (fct != NULL)
846	{
847	if (req->ai_family == AF_INET6
848	\|\| req->ai_family == AF_UNSPEC)
849	{
850	gethosts (AF_INET6, struct in6_addr);
851	no_inet6_data = no_data;
852	inet6_status = status;
853	}
854	if (req->ai_family == AF_INET
855	\|\| req->ai_family == AF_UNSPEC
856	\|\| (req->ai_family == AF_INET6
857	&& (req->ai_flags & AI_V4MAPPED)
858	/* Avoid generating the mapped addresses if we
859	know we are not going to need them. */
860	&& ((req->ai_flags & AI_ALL) \|\| !got_ipv6)))
861	{
862	gethosts (AF_INET, struct in_addr);
863
864	if (req->ai_family == AF_INET)
865	{
866	no_inet6_data = no_data;
867	inet6_status = status;
868	}
869	}
870
871	/* If we found one address for AF_INET or AF_INET6,
872	don't continue the search. */
873	if (inet6_status == NSS_STATUS_SUCCESS
874	\|\| status == NSS_STATUS_SUCCESS)
875	{
876	if ((req->ai_flags & AI_CANONNAME) != 0 && canon == NULL)
877	{
878	/* If we need the canonical name, get it
879	from the same service as the result. */
880	nss_getcanonname_r cfct;
881	int herrno;
882
883	cfct = __nss_lookup_function (nip, "getcanonname_r");
884	if (cfct != NULL)
885	{
886	const size_t max_fqdn_len = 256;
887	char *buf = alloca (max_fqdn_len);
888	char *s;
889
890	if (DL_CALL_FCT (cfct, (at->name ?: name, buf,
891	max_fqdn_len, &s, &rc,
892	&herrno))
893	== NSS_STATUS_SUCCESS)
894	canon = s;
895	else
896	/* Set to name now to avoid using
897	gethostbyaddr. */
898	canon = name;
899	}
900	}
901
902	break;
903	}
904
905	/* We can have different states for AF_INET and
906	AF_INET6. Try to find a useful one for both. */
907	if (inet6_status == NSS_STATUS_TRYAGAIN)
908	status = NSS_STATUS_TRYAGAIN;
909	else if (status == NSS_STATUS_UNAVAIL &&
910	inet6_status != NSS_STATUS_UNAVAIL)
911	status = inet6_status;
912	}
913
914	if (nss_next_action (nip, status) == NSS_ACTION_RETURN)
915	break;
916
917	if (nip->next == NULL)
918	no_more = -1;
919	else
920	nip = nip->next;
921	}
922
923	_res.options = old_res_options;
924
925	if (no_data != 0 && no_inet6_data != 0)
926	{
927	/* If both requests timed out report this. */
928	if (no_data == EAI_AGAIN && no_inet6_data == EAI_AGAIN)
929	return -EAI_AGAIN;
930
931	/* We made requests but they turned out no data. The name
932	is known, though. */
933	return (GAIH_OKIFUNSPEC \| -EAI_NODATA);
934	}
935	}
936
937	process_list:
938	if (at->family == AF_UNSPEC)
939	return (GAIH_OKIFUNSPEC \| -EAI_NONAME);
940	}
941	else
942	{
943	struct gaih_addrtuple *atr;
944	atr = at = alloca (sizeof (struct gaih_addrtuple));
945	memset (at, '\0', sizeof (struct gaih_addrtuple));
946
947	if (req->ai_family == AF_UNSPEC)
948	{
949	at->next = alloca (sizeof (struct gaih_addrtuple));
950	memset (at->next, '\0', sizeof (struct gaih_addrtuple));
951	}
952
953	if (req->ai_family == AF_UNSPEC \|\| req->ai_family == AF_INET6)
954	{
955	at->family = AF_INET6;
956	if ((req->ai_flags & AI_PASSIVE) == 0)
957	memcpy (at->addr, &in6addr_loopback, sizeof (struct in6_addr));
958	atr = at->next;
959	}
960
961	if (req->ai_family == AF_UNSPEC \|\| req->ai_family == AF_INET)
962	{
963	atr->family = AF_INET;
964	if ((req->ai_flags & AI_PASSIVE) == 0)
965	atr->addr[0] = htonl (INADDR_LOOPBACK);
966	}
967	}
968
969	if (pai == NULL)
970	return 0;
971
972	{
973	struct gaih_servtuple *st2;
974	struct gaih_addrtuple *at2 = at;
975	size_t socklen;
976	sa_family_t family;
977
978	/*
979	buffer is the size of an unformatted IPv6 address in printable format.
980	*/
981	while (at2 != NULL)
982	{
983	/* Only the first entry gets the canonical name. */
984	if (at2 == at && (req->ai_flags & AI_CANONNAME) != 0)
985	{
986	if (canon == NULL)
987	{
988	struct hostent *h = NULL;
989	int herrno;
990	struct hostent th;
991	size_t tmpbuflen = 512;
992	char *tmpbuf = NULL;
993
994	do
995	{
996	tmpbuf = extend_alloca (tmpbuf, tmpbuflen, tmpbuflen * 2);
997	rc = __gethostbyaddr_r (at2->addr,
998	((at2->family == AF_INET6)
999	? sizeof (struct in6_addr)
1000	: sizeof (struct in_addr)),
1001	at2->family, &th, tmpbuf,
1002	tmpbuflen, &h, &herrno);
1003	}
1004	while (rc == ERANGE && herrno == NETDB_INTERNAL);
1005
1006	if (rc != 0 && herrno == NETDB_INTERNAL)
1007	{
1008	h_errno = (herrno);
1009	return -EAI_SYSTEM;
1010	}
1011
1012	if (h != NULL)
1013	canon = h->h_name;
1014	else
1015	{
1016	assert (orig_name != NULL);
1017	/* If the canonical name cannot be determined, use
1018	the passed in string. */
1019	canon = orig_name;
1020	}
1021	}
1022
1023	#ifdef HAVE_LIBIDN
1024	if (req->ai_flags & AI_CANONIDN)
1025	{
1026	int idn_flags = 0;
1027	if (req->ai_flags & AI_IDN_ALLOW_UNASSIGNED)
1028	idn_flags \|= IDNA_ALLOW_UNASSIGNED;
1029	if (req->ai_flags & AI_IDN_USE_STD3_ASCII_RULES)
1030	idn_flags \|= IDNA_USE_STD3_ASCII_RULES;
1031
1032	char *out;
1033	int rc = __idna_to_unicode_lzlz (canon, &out, idn_flags);
1034	if (rc != IDNA_SUCCESS)
1035	{
1036	if (rc == IDNA_MALLOC_ERROR)
1037	return -EAI_MEMORY;
1038	if (rc == IDNA_DLOPEN_ERROR)
1039	return -EAI_SYSTEM;
1040	return -EAI_IDN_ENCODE;
1041	}
1042	/* In case the output string is the same as the input
1043	string no new string has been allocated. Otherwise
1044	make a copy. */
1045	if (out == canon)
1046	goto make_copy;
1047	}
1048	else
1049	#endif
1050	{
1051	#ifdef HAVE_LIBIDN
1052	make_copy:
1053	#endif
1054	canon = strdup (canon);
1055	if (canon == NULL)
1056	return -EAI_MEMORY;
1057	}
1058	}
1059
1060	if (at2->family == AF_INET6)
1061	{
1062	family = AF_INET6;
1063	socklen = sizeof (struct sockaddr_in6);
1064
1065	/* If we looked up IPv4 mapped address discard them here if
1066	the caller isn't interested in all address and we have
1067	found at least one IPv6 address. */
1068	if (got_ipv6
1069	&& (req->ai_flags & (AI_V4MAPPED\|AI_ALL)) == AI_V4MAPPED
1070	&& IN6_IS_ADDR_V4MAPPED ((struct in6_addr *)at2->addr))
1071	goto ignore;
1072	}
1073	else
1074	{
1075	family = AF_INET;
1076	socklen = sizeof (struct sockaddr_in);
1077	}
1078
1079	for (st2 = st; st2 != NULL; st2 = st2->next)
1080	{
1081	struct addrinfo *ai;
1082	ai = *pai = malloc (sizeof (struct addrinfo) + socklen);
1083	if (ai == NULL)
1084	return -EAI_MEMORY;
1085
1086	ai->ai_flags = req->ai_flags;
1087	ai->ai_family = family;
1088	ai->ai_socktype = st2->socktype;
1089	ai->ai_protocol = st2->protocol;
1090	ai->ai_addrlen = socklen;
1091	ai->ai_addr = (void *) (ai + 1);
1092
1093	/* We only add the canonical name once. */
1094	ai->ai_canonname = (char *) canon;
1095	canon = NULL;
1096
1097	#if SALEN
1098	ai->ai_addr->sa_len = socklen;
1099	#endif /* SALEN */
1100	ai->ai_addr->sa_family = family;
1101
1102	if (family == AF_INET6)
1103	{
1104	struct sockaddr_in6 *sin6p =
1105	(struct sockaddr_in6 *) ai->ai_addr;
1106
1107	sin6p->sin6_port = st2->port;
1108	sin6p->sin6_flowinfo = 0;
1109	memcpy (&sin6p->sin6_addr,
1110	at2->addr, sizeof (struct in6_addr));
1111	sin6p->sin6_scope_id = at2->scopeid;
1112	}
1113	else
1114	{
1115	struct sockaddr_in *sinp =
1116	(struct sockaddr_in *) ai->ai_addr;
1117	sinp->sin_port = st2->port;
1118	memcpy (&sinp->sin_addr,
1119	at2->addr, sizeof (struct in_addr));
1120	memset (sinp->sin_zero, '\0', sizeof (sinp->sin_zero));
1121	}
1122
1123	pai = &(ai->ai_next);
1124	}
1125	*pai = NULL;
1126
1127	ignore:
1128	at2 = at2->next;
1129	}
1130	}
1131	return 0;
1132	}
1133
1134	static struct gaih gaih[] =
1135	{
1136	{ PF_INET6, gaih_inet },
1137	{ PF_INET, gaih_inet },
1138	#if 0
1139	{ PF_LOCAL, gaih_local },
1140	#endif
1141	{ PF_UNSPEC, NULL }
1142	};
1143
1144	struct sort_result
1145	{
1146	struct addrinfo *dest_addr;
1147	struct sockaddr_storage source_addr;
1148	uint8_t source_addr_len;
1149	bool got_source_addr;
1150	};
1151
1152
1153	static int
1154	get_scope (const struct sockaddr_storage *ss)
1155	{
1156	int scope;
1157	if (ss->ss_family == PF_INET6)
1158	{
1159	const struct sockaddr_in6 in6 = (const struct sockaddr_in6 ) ss;
1160
1161	if (! IN6_IS_ADDR_MULTICAST (&in6->sin6_addr))
1162	{
1163	if (IN6_IS_ADDR_LINKLOCAL (&in6->sin6_addr))
1164	scope = 2;
1165	else if (IN6_IS_ADDR_SITELOCAL (&in6->sin6_addr))
1166	scope = 5;
1167	else
1168	/* XXX Is this the correct default behavior? */
1169	scope = 14;
1170	}
1171	else
1172	scope = in6->sin6_addr.s6_addr[1] & 0xf;
1173	}
1174	else if (ss->ss_family == PF_INET)
1175	{
1176	const struct sockaddr_in in = (const struct sockaddr_in ) ss;
1177	const uint8_t addr = (const uint8_t ) &in->sin_addr;
1178
1179	/* RFC 3484 specifies how to map IPv6 addresses to scopes.
1180	169.254/16 and 127/8 are link-local. */
1181	if ((addr[0] == 169 && addr[1] == 254) \|\| addr[0] == 127)
1182	scope = 2;
1183	else if (addr[0] == 10 \|\| (addr[0] == 172 && addr[1] == 16)
1184	\|\| (addr[0] == 192 && addr[1] == 168))
1185	scope = 5;
1186	else
1187	scope = 14;
1188	}
1189	else
1190	/* XXX What is a good default? */
1191	scope = 15;
1192
1193	return scope;
1194	}
1195
1196
1197	/* XXX The system administrator should be able to install other
1198	tables. We need to make this configurable. The problem is that
1199	the kernel is also involved since it needs the same table. */
1200	static const struct prefixlist
1201	{
1202	struct in6_addr prefix;
1203	unsigned int bits;
1204	int val;
1205	} default_labels[] =
1206	{
1207	/* See RFC 3484 for the details. */
1208	{ { .__u6_addr = { .__u6_addr16 = { 0x0000, 0x0000, 0x0000, 0x0000,
1209	0x0000, 0x0000, 0x0000, 0x0001 } } },
1210	128, 0 },
1211	{ { .__u6_addr = { .__u6_addr16 = { 0x2002, 0x0000, 0x0000, 0x0000,
1212	0x0000, 0x0000, 0x0000, 0x0000 } } },
1213	16, 2 },
1214	{ { .__u6_addr = { .__u6_addr16 = { 0x0000, 0x0000, 0x0000, 0x0000,
1215	0x0000, 0x0000, 0x0000, 0x0000 } } },
1216	96, 3 },
1217	{ { .__u6_addr = { .__u6_addr16 = { 0x0000, 0x0000, 0x0000, 0x0000,
1218	0x0000, 0xffff, 0x0000, 0x0000 } } },
1219	96, 4 },
1220	{ { .__u6_addr = { .__u6_addr16 = { 0x0000, 0x0000, 0x0000, 0x0000,
1221	0x0000, 0x0000, 0x0000, 0x0000 } } },
1222	0, 1 }
1223	};
1224
1225
1226	static const struct prefixlist default_precedence[] =
1227	{
1228	/* See RFC 3484 for the details. */
1229	{ { .__u6_addr = { .__u6_addr16 = { 0x0000, 0x0000, 0x0000, 0x0000,
1230	0x0000, 0x0000, 0x0000, 0x0001 } } },
1231	128, 50 },
1232	{ { .__u6_addr = { .__u6_addr16 = { 0x2002, 0x0000, 0x0000, 0x0000,
1233	0x0000, 0x0000, 0x0000, 0x0000 } } },
1234	16, 30 },
1235	{ { .__u6_addr = { .__u6_addr16 = { 0x0000, 0x0000, 0x0000, 0x0000,
1236	0x0000, 0x0000, 0x0000, 0x0000 } } },
1237	96, 20 },
1238	{ { .__u6_addr = { .__u6_addr16 = { 0x0000, 0x0000, 0x0000, 0x0000,
1239	0x0000, 0xffff, 0x0000, 0x0000 } } },
1240	96, 10 },
1241	{ { .__u6_addr = { .__u6_addr16 = { 0x0000, 0x0000, 0x0000, 0x0000,
1242	0x0000, 0x0000, 0x0000, 0x0000 } } },
1243	0, 40 }
1244	};
1245
1246
1247	static int
1248	match_prefix (const struct sockaddr_storage ss, const struct prefixlist list,
1249	int default_val)
1250	{
1251	int idx;
1252	struct sockaddr_in6 in6_mem;
1253	const struct sockaddr_in6 *in6;
1254
1255	if (ss->ss_family == PF_INET6)
1256	in6 = (const struct sockaddr_in6 *) ss;
1257	else if (ss->ss_family == PF_INET)
1258	{
1259	const struct sockaddr_in in = (const struct sockaddr_in ) ss;
1260
1261	/* Convert to IPv6 address. */
1262	in6_mem.sin6_family = PF_INET6;
1263	in6_mem.sin6_port = in->sin_port;
1264	in6_mem.sin6_flowinfo = 0;
1265	if (in->sin_addr.s_addr == htonl (0x7f000001))
1266	in6_mem.sin6_addr = (struct in6_addr) IN6ADDR_LOOPBACK_INIT;
1267	else
1268	{
1269	/* Construct a V4-to-6 mapped address. */
1270	memset (&in6_mem.sin6_addr, '\0', sizeof (in6_mem.sin6_addr));
1271	in6_mem.sin6_addr.__u6_addr.__u6_addr16[5] = 0xffff;
1272	in6_mem.sin6_addr.__u6_addr.__u6_addr32[3] = in->sin_addr.s_addr;
1273	in6_mem.sin6_scope_id = 0;
1274	}
1275
1276	in6 = &in6_mem;
1277	}
1278	else
1279	return default_val;
1280
1281	for (idx = 0; ; ++idx)
1282	{
1283	unsigned int bits = list[idx].bits;
1284	uint8_t *mask = list[idx].prefix.s6_addr;
1285	uint8_t *val = in6->sin6_addr.s6_addr;
1286
1287	while (bits > 8)
1288	{
1289	if (mask != val)
1290	break;
1291
1292	++mask;
1293	++val;
1294	bits -= 8;
1295	}
1296
1297	if (bits < 8)
1298	{
1299	if ((mask & (0xff00 >> bits)) == (val & (0xff00 >> bits)))
1300	/* Match! */
1301	break;
1302	}
1303	}
1304
1305	return list[idx].val;
1306	}
1307
1308
1309	static int
1310	get_label (const struct sockaddr_storage *ss)
1311	{
1312	/* XXX What is a good default value? */
1313	return match_prefix (ss, default_labels, INT_MAX);
1314	}
1315
1316
1317	static int
1318	get_precedence (const struct sockaddr_storage *ss)
1319	{
1320	/* XXX What is a good default value? */
1321	return match_prefix (ss, default_precedence, 0);
1322	}
1323
1324
1325	static int
1326	rfc3484_sort (const void p1, const void p2)
1327	{
1328	const struct sort_result a1 = (const struct sort_result ) p1;
1329	const struct sort_result a2 = (const struct sort_result ) p2;
1330
1331	/* Rule 1: Avoid unusable destinations.
1332	We have the got_source_addr flag set if the destination is reachable. */
1333	if (a1->got_source_addr && ! a2->got_source_addr)
1334	return -1;
1335	if (! a1->got_source_addr && a2->got_source_addr)
1336	return 1;
1337
1338
1339	/* Rule 2: Prefer matching scope. Only interesting if both
1340	destination addresses are IPv6. */
1341	int a1_dst_scope
1342	= get_scope ((struct sockaddr_storage *) a1->dest_addr->ai_addr);
1343
1344	int a2_dst_scope
1345	= get_scope ((struct sockaddr_storage *) a2->dest_addr->ai_addr);
1346
1347	if (a1->got_source_addr)
1348	{
1349	int a1_src_scope = get_scope (&a1->source_addr);
1350	int a2_src_scope = get_scope (&a2->source_addr);
1351
1352	if (a1_dst_scope == a1_src_scope && a2_dst_scope != a2_src_scope)
1353	return -1;
1354	if (a1_dst_scope != a1_src_scope && a2_dst_scope == a2_src_scope)
1355	return 1;
1356	}
1357
1358
1359	/* Rule 3: Avoid deprecated addresses.
1360	That's something only the kernel could decide. */
1361
1362	/* Rule 4: Prefer home addresses.
1363	Another thing only the kernel can decide. */
1364
1365	/* Rule 5: Prefer matching label. */
1366	if (a1->got_source_addr)
1367	{
1368	int a1_dst_label
1369	= get_label ((struct sockaddr_storage *) a1->dest_addr->ai_addr);
1370	int a1_src_label = get_label (&a1->source_addr);
1371
1372	int a2_dst_label
1373	= get_label ((struct sockaddr_storage *) a2->dest_addr->ai_addr);
1374	int a2_src_label = get_label (&a2->source_addr);
1375
1376	if (a1_dst_label == a1_src_label && a2_dst_label != a2_src_label)
1377	return -1;
1378	if (a1_dst_label != a1_src_label && a2_dst_label == a2_src_label)
1379	return 1;
1380	}
1381
1382
1383	/* Rule 6: Prefer higher precedence. */
1384	int a1_prec
1385	= get_precedence ((struct sockaddr_storage *) a1->dest_addr->ai_addr);
1386	int a2_prec
1387	= get_precedence ((struct sockaddr_storage *) a2->dest_addr->ai_addr);
1388
1389	if (a1_prec > a2_prec)
1390	return -1;
1391	if (a1_prec < a2_prec)
1392	return 1;
1393
1394
1395	/* Rule 7: Prefer native transport.
1396	XXX How to recognize tunnels? */
1397
1398
1399	/* Rule 8: Prefer smaller scope. */
1400	if (a1_dst_scope < a2_dst_scope)
1401	return -1;
1402	if (a1_dst_scope > a2_dst_scope)
1403	return 1;
1404
1405
1406	/* Rule 9: Use longest matching prefix. */
1407	if (a1->got_source_addr
1408	&& a1->dest_addr->ai_family == a2->dest_addr->ai_family)
1409	{
1410	int bit1 = 0;
1411	int bit2 = 0;
1412
1413	if (a1->dest_addr->ai_family == PF_INET)
1414	{
1415	assert (a1->source_addr.ss_family == PF_INET);
1416	assert (a2->source_addr.ss_family == PF_INET);
1417
1418	struct sockaddr_in *in1_dst;
1419	struct sockaddr_in *in1_src;
1420	struct sockaddr_in *in2_dst;
1421	struct sockaddr_in *in2_src;
1422
1423	in1_dst = (struct sockaddr_in *) a1->dest_addr->ai_addr;
1424	in1_src = (struct sockaddr_in *) &a1->source_addr;
1425	in2_dst = (struct sockaddr_in *) a2->dest_addr->ai_addr;
1426	in2_src = (struct sockaddr_in *) &a2->source_addr;
1427
1428	bit1 = ffs (in1_dst->sin_addr.s_addr ^ in1_src->sin_addr.s_addr);
1429	bit2 = ffs (in2_dst->sin_addr.s_addr ^ in2_src->sin_addr.s_addr);
1430	}
1431	else if (a1->dest_addr->ai_family == PF_INET6)
1432	{
1433	assert (a1->source_addr.ss_family == PF_INET6);
1434	assert (a2->source_addr.ss_family == PF_INET6);
1435
1436	struct sockaddr_in6 *in1_dst;
1437	struct sockaddr_in6 *in1_src;
1438	struct sockaddr_in6 *in2_dst;
1439	struct sockaddr_in6 *in2_src;
1440
1441	in1_dst = (struct sockaddr_in6 *) a1->dest_addr->ai_addr;
1442	in1_src = (struct sockaddr_in6 *) &a1->source_addr;
1443	in2_dst = (struct sockaddr_in6 *) a2->dest_addr->ai_addr;
1444	in2_src = (struct sockaddr_in6 *) &a2->source_addr;
1445
1446	int i;
1447	for (i = 0; i < 4; ++i)
1448	if (in1_dst->sin6_addr.s6_addr32[i]
1449	!= in1_src->sin6_addr.s6_addr32[i]
1450	\|\| (in2_dst->sin6_addr.s6_addr32[i]
1451	!= in2_src->sin6_addr.s6_addr32[i]))
1452	break;
1453
1454	if (i < 4)
1455	{
1456	bit1 = ffs (in1_dst->sin6_addr.s6_addr32[i]
1457	^ in1_src->sin6_addr.s6_addr32[i]);
1458	bit2 = ffs (in2_dst->sin6_addr.s6_addr32[i]
1459	^ in2_src->sin6_addr.s6_addr32[i]);
1460	}
1461	}
1462
1463	if (bit1 > bit2)
1464	return -1;
1465	if (bit1 < bit2)
1466	return 1;
1467	}
1468
1469
1470	/* Rule 10: Otherwise, leave the order unchanged. */
1471	return 0;
1472	}
1473
1474
1475	int
1476	getaddrinfo (const char __restrict name, const char __restrict service,
1477	const struct addrinfo *__restrict hints,
1478	struct addrinfo **__restrict pai)
1479	{
1480	int i = 0, j = 0, last_i = 0;
1481	int nresults = 0;
1482	struct addrinfo p = NULL, *end;
1483	struct gaih g = gaih, pg = NULL;
1484	struct gaih_service gaih_service, *pservice;
1485	struct addrinfo local_hints;
1486
1487	if (name != NULL && name[0] == '*' && name[1] == 0)
1488	name = NULL;
1489
1490	if (service != NULL && service[0] == '*' && service[1] == 0)
1491	service = NULL;
1492
1493	if (name == NULL && service == NULL)
1494	return EAI_NONAME;
1495
1496	if (hints == NULL)
1497	hints = &default_hints;
1498
1499	if (hints->ai_flags
1500	& ~(AI_PASSIVE\|AI_CANONNAME\|AI_NUMERICHOST\|AI_ADDRCONFIG\|AI_V4MAPPED
1501	#ifdef HAVE_LIBIDN
1502	\|AI_IDN\|AI_CANONIDN\|AI_IDN_ALLOW_UNASSIGNED
1503	\|AI_IDN_USE_STD3_ASCII_RULES
1504	#endif
1505	\|AI_NUMERICSERV\|AI_ALL))
1506	return EAI_BADFLAGS;
1507
1508	if ((hints->ai_flags & AI_CANONNAME) && name == NULL)
1509	return EAI_BADFLAGS;
1510
1511	if (hints->ai_flags & AI_ADDRCONFIG)
1512	{
1513	/* Determine whether we have IPv4 or IPv6 interfaces or both.
1514	We cannot cache the results since new interfaces could be
1515	added at any time. */
1516	bool seen_ipv4;
1517	bool seen_ipv6;
1518	__check_pf (&seen_ipv4, &seen_ipv6);
1519
1520	/* Now make a decision on what we return, if anything. */
1521	if (hints->ai_family == PF_UNSPEC && (seen_ipv4 \|\| seen_ipv6))
1522	{
1523	/* If we haven't seen both IPv4 and IPv6 interfaces we can
1524	narrow down the search. */
1525	if (! seen_ipv4 \|\| ! seen_ipv6)
1526	{
1527	local_hints = *hints;
1528	local_hints.ai_family = seen_ipv4 ? PF_INET : PF_INET6;
1529	hints = &local_hints;
1530	}
1531	}
1532	else if ((hints->ai_family == PF_INET && ! seen_ipv4)
1533	\|\| (hints->ai_family == PF_INET6 && ! seen_ipv6))
1534	/* We cannot possibly return a valid answer. */
1535	return EAI_NONAME;
1536	}
1537
1538	if (service && service[0])
1539	{
1540	char *c;
1541	gaih_service.name = service;
1542	gaih_service.num = strtoul (gaih_service.name, &c, 10);
1543	if (*c != '\0')
1544	{
1545	if (hints->ai_flags & AI_NUMERICSERV)
1546	return EAI_NONAME;
1547
1548	gaih_service.num = -1;
1549	}
1550
1551	pservice = &gaih_service;
1552	}
1553	else
1554	pservice = NULL;
1555
1556	if (pai)
1557	end = &p;
1558	else
1559	end = NULL;
1560
1561	while (g->gaih)
1562	{
1563	if (hints->ai_family == g->family \|\| hints->ai_family == AF_UNSPEC)
1564	{
1565	j++;
1566	if (pg == NULL \|\| pg->gaih != g->gaih)
1567	{
1568	pg = g;
1569	i = g->gaih (name, pservice, hints, end);
1570	if (i != 0)
1571	{
1572	/* EAI_NODATA is a more specific result as it says that
1573	we found a result but it is not usable. */
1574	if (last_i != (GAIH_OKIFUNSPEC \| -EAI_NODATA))
1575	last_i = i;
1576
1577	if (hints->ai_family == AF_UNSPEC && (i & GAIH_OKIFUNSPEC))
1578	{
1579	++g;
1580	continue;
1581	}
1582
1583	freeaddrinfo (p);
1584
1585	return -(i & GAIH_EAI);
1586	}
1587	if (end)
1588	while (*end)
1589	{
1590	end = &((*end)->ai_next);
1591	++nresults;
1592	}
1593	}
1594	}
1595	++g;
1596	}
1597
1598	if (j == 0)
1599	return EAI_FAMILY;
1600
1601	if (nresults > 1)
1602	{
1603	/* Sort results according to RFC 3484. */
1604	struct sort_result results[nresults];
1605	struct addrinfo *q;
1606	struct addrinfo *last = NULL;
1607	char *canonname = NULL;
1608
1609	for (i = 0, q = p; q != NULL; ++i, last = q, q = q->ai_next)
1610	{
1611	results[i].dest_addr = q;
1612	results[i].got_source_addr = false;
1613
1614	/* If we just looked up the address for a different
1615	protocol, reuse the result. */
1616	if (last != NULL && last->ai_addrlen == q->ai_addrlen
1617	&& memcmp (last->ai_addr, q->ai_addr, q->ai_addrlen) == 0)
1618	{
1619	memcpy (&results[i].source_addr, &results[i - 1].source_addr,
1620	results[i - 1].source_addr_len);
1621	results[i].source_addr_len = results[i - 1].source_addr_len;
1622	results[i].got_source_addr = results[i - 1].got_source_addr;
1623	}
1624	else
1625	{
1626	/* We overwrite the type with SOCK_DGRAM since we do not
1627	want connect() to connect to the other side. If we
1628	cannot determine the source address remember this
1629	fact. */
1630	int fd = socket (q->ai_family, SOCK_DGRAM, IPPROTO_IP);
1631	socklen_t sl = sizeof (results[i].source_addr);
1632	if (fd != -1
1633	&& connect (fd, q->ai_addr, q->ai_addrlen) == 0
1634	&& getsockname (fd,
1635	(struct sockaddr *) &results[i].source_addr,
1636	&sl) == 0)
1637	{
1638	results[i].source_addr_len = sl;
1639	results[i].got_source_addr = true;
1640	}
1641	else
1642	/* Just make sure that if we have to process the same
1643	address again we do not copy any memory. */
1644	results[i].source_addr_len = 0;
1645
1646	if (fd != -1)
1647	close_not_cancel_no_status (fd);
1648	}
1649
1650	/* Remember the canonical name. */
1651	if (q->ai_canonname != NULL)
1652	{
1653	assert (canonname == NULL);
1654	canonname = q->ai_canonname;
1655	q->ai_canonname = NULL;
1656	}
1657	}
1658
1659	/* We got all the source addresses we can get, now sort using
1660	the information. */
1661	qsort (results, nresults, sizeof (results[0]), rfc3484_sort);
1662
1663	/* Queue the results up as they come out of sorting. */
1664	q = p = results[0].dest_addr;
1665	for (i = 1; i < nresults; ++i)
1666	q = q->ai_next = results[i].dest_addr;
1667	q->ai_next = NULL;
1668
1669	/* Fill in the canonical name into the new first entry. */
1670	p->ai_canonname = canonname;
1671	}
1672
1673	if (p)
1674	{
1675	*pai = p;
1676	return 0;
1677	}
1678
1679	if (pai == NULL && last_i == 0)
1680	return 0;
1681
1682	return last_i ? -(last_i & GAIH_EAI) : EAI_NONAME;
1683	}
1684	libc_hidden_def (getaddrinfo)
1685
1686	static_link_warning (getaddrinfo)
1687
1688	void
1689	freeaddrinfo (struct addrinfo *ai)
1690	{
1691	struct addrinfo *p;
1692
1693	while (ai != NULL)
1694	{
1695	p = ai;
1696	ai = ai->ai_next;
1697	free (p->ai_canonname);
1698	free (p);
1699	}
1700	}
1701	libc_hidden_def (freeaddrinfo)

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source: trunk/libs/newlib/src/newlib/libc/sys/linux/net/getaddrinfo.c

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