1 /* Copyright (C) 1996-2013 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Extended from original form by Ulrich Drepper <drepper@cygnus.com>, 1996.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <http://www.gnu.org/licenses/>. */
19 /* Parts of this file are plain copies of the file `gethtnamadr.c' from
20 the bind package and it has the following copyright. */
23 * ++Copyright++ 1985, 1988, 1993
25 * Copyright (c) 1985, 1988, 1993
26 * The Regents of the University of California. All rights reserved.
28 * Redistribution and use in source and binary forms, with or without
29 * modification, are permitted provided that the following conditions
31 * 1. Redistributions of source code must retain the above copyright
32 * notice, this list of conditions and the following disclaimer.
33 * 2. Redistributions in binary form must reproduce the above copyright
34 * notice, this list of conditions and the following disclaimer in the
35 * documentation and/or other materials provided with the distribution.
36 * 4. Neither the name of the University nor the names of its contributors
37 * may be used to endorse or promote products derived from this software
38 * without specific prior written permission.
40 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
43 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
52 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
54 * Permission to use, copy, modify, and distribute this software for any
55 * purpose with or without fee is hereby granted, provided that the above
56 * copyright notice and this permission notice appear in all copies, and that
57 * the name of Digital Equipment Corporation not be used in advertising or
58 * publicity pertaining to distribution of the document or software without
59 * specific, written prior permission.
61 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
62 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
63 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
64 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
65 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
66 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
67 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
81 #include <sys/syslog.h>
85 /* Get implementation for some internal functions. */
86 #include <resolv/mapv4v6addr.h>
87 #include <resolv/mapv4v6hostent.h>
92 # define MAXPACKET PACKETSZ
94 # define MAXPACKET 65536
96 /* As per RFC 1034 and 1035 a host name cannot exceed 255 octets in length. */
98 # undef MAXHOSTNAMELEN
100 #define MAXHOSTNAMELEN 256
102 static const char AskedForGot
[] = "\
103 gethostby*.getanswer: asked for \"%s\", got \"%s\"";
106 /* We need this time later. */
107 typedef union querybuf
110 u_char buf
[MAXPACKET
];
113 /* These functions are defined in res_comp.c. */
114 #define NS_MAXCDNAME 255 /* maximum compressed domain name */
115 extern int __ns_name_ntop (const u_char
*, char *, size_t);
116 extern int __ns_name_unpack (const u_char
*, const u_char
*,
117 const u_char
*, u_char
*, size_t);
120 static enum nss_status
getanswer_r (const querybuf
*answer
, int anslen
,
121 const char *qname
, int qtype
,
122 struct hostent
*result
, char *buffer
,
123 size_t buflen
, int *errnop
, int *h_errnop
,
124 int map
, int32_t *ttlp
, char **canonp
);
126 static enum nss_status
gaih_getanswer (const querybuf
*answer1
, int anslen1
,
127 const querybuf
*answer2
, int anslen2
,
129 struct gaih_addrtuple
**pat
,
130 char *buffer
, size_t buflen
,
131 int *errnop
, int *h_errnop
,
134 extern enum nss_status
_nss_dns_gethostbyname3_r (const char *name
, int af
,
135 struct hostent
*result
,
136 char *buffer
, size_t buflen
,
137 int *errnop
, int *h_errnop
,
140 hidden_proto (_nss_dns_gethostbyname3_r
)
143 _nss_dns_gethostbyname3_r (const char *name
, int af
, struct hostent
*result
,
144 char *buffer
, size_t buflen
, int *errnop
,
145 int *h_errnop
, int32_t *ttlp
, char **canonp
)
152 querybuf
*orig_host_buffer
;
153 char tmp
[NS_MAXDNAME
];
158 enum nss_status status
;
160 if (__res_maybe_init (&_res
, 0) == -1)
161 return NSS_STATUS_UNAVAIL
;
174 *errnop
= EAFNOSUPPORT
;
175 return NSS_STATUS_UNAVAIL
;
178 result
->h_addrtype
= af
;
179 result
->h_length
= size
;
182 * if there aren't any dots, it could be a user-level alias.
183 * this is also done in res_query() since we are not the only
184 * function that looks up host names.
186 if (strchr (name
, '.') == NULL
187 && (cp
= res_hostalias (&_res
, name
, tmp
, sizeof (tmp
))) != NULL
)
190 host_buffer
.buf
= orig_host_buffer
= (querybuf
*) alloca (1024);
192 n
= __libc_res_nsearch (&_res
, name
, C_IN
, type
, host_buffer
.buf
->buf
,
193 1024, &host_buffer
.ptr
, NULL
, NULL
, NULL
);
199 status
= NSS_STATUS_TRYAGAIN
;
202 /* System has run out of file descriptors. */
205 h_errno
= NETDB_INTERNAL
;
209 status
= NSS_STATUS_UNAVAIL
;
212 status
= NSS_STATUS_NOTFOUND
;
216 if (h_errno
== TRY_AGAIN
)
219 __set_errno (olderr
);
221 /* If we are looking for an IPv6 address and mapping is enabled
222 by having the RES_USE_INET6 bit in _res.options set, we try
224 if (af
== AF_INET6
&& (_res
.options
& RES_USE_INET6
))
225 n
= __libc_res_nsearch (&_res
, name
, C_IN
, T_A
, host_buffer
.buf
->buf
,
226 host_buffer
.buf
!= orig_host_buffer
227 ? MAXPACKET
: 1024, &host_buffer
.ptr
,
232 if (host_buffer
.buf
!= orig_host_buffer
)
233 free (host_buffer
.buf
);
239 result
->h_addrtype
= AF_INET
;
240 result
->h_length
= INADDRSZ
;
243 status
= getanswer_r (host_buffer
.buf
, n
, name
, type
, result
, buffer
, buflen
,
244 errnop
, h_errnop
, map
, ttlp
, canonp
);
245 if (host_buffer
.buf
!= orig_host_buffer
)
246 free (host_buffer
.buf
);
249 hidden_def (_nss_dns_gethostbyname3_r
)
253 _nss_dns_gethostbyname2_r (const char *name
, int af
, struct hostent
*result
,
254 char *buffer
, size_t buflen
, int *errnop
,
257 return _nss_dns_gethostbyname3_r (name
, af
, result
, buffer
, buflen
, errnop
,
258 h_errnop
, NULL
, NULL
);
263 _nss_dns_gethostbyname_r (const char *name
, struct hostent
*result
,
264 char *buffer
, size_t buflen
, int *errnop
,
267 enum nss_status status
= NSS_STATUS_NOTFOUND
;
269 if (_res
.options
& RES_USE_INET6
)
270 status
= _nss_dns_gethostbyname3_r (name
, AF_INET6
, result
, buffer
,
271 buflen
, errnop
, h_errnop
, NULL
, NULL
);
272 if (status
== NSS_STATUS_NOTFOUND
)
273 status
= _nss_dns_gethostbyname3_r (name
, AF_INET
, result
, buffer
,
274 buflen
, errnop
, h_errnop
, NULL
, NULL
);
281 _nss_dns_gethostbyname4_r (const char *name
, struct gaih_addrtuple
**pat
,
282 char *buffer
, size_t buflen
, int *errnop
,
283 int *herrnop
, int32_t *ttlp
)
285 if (__res_maybe_init (&_res
, 0) == -1)
286 return NSS_STATUS_UNAVAIL
;
289 * if there aren't any dots, it could be a user-level alias.
290 * this is also done in res_query() since we are not the only
291 * function that looks up host names.
293 if (strchr (name
, '.') == NULL
)
295 char *tmp
= alloca (NS_MAXDNAME
);
296 const char *cp
= res_hostalias (&_res
, name
, tmp
, NS_MAXDNAME
);
306 querybuf
*orig_host_buffer
;
307 host_buffer
.buf
= orig_host_buffer
= (querybuf
*) alloca (2048);
308 u_char
*ans2p
= NULL
;
313 enum nss_status status
;
314 int n
= __libc_res_nsearch (&_res
, name
, C_IN
, T_UNSPEC
,
315 host_buffer
.buf
->buf
, 2048, &host_buffer
.ptr
,
316 &ans2p
, &nans2p
, &resplen2
);
322 status
= NSS_STATUS_TRYAGAIN
;
325 /* System has run out of file descriptors. */
328 h_errno
= NETDB_INTERNAL
;
332 status
= NSS_STATUS_UNAVAIL
;
335 status
= NSS_STATUS_NOTFOUND
;
340 if (h_errno
== TRY_AGAIN
)
343 __set_errno (olderr
);
345 if (host_buffer
.buf
!= orig_host_buffer
)
346 free (host_buffer
.buf
);
351 status
= gaih_getanswer(host_buffer
.buf
, n
, (const querybuf
*) ans2p
,
352 resplen2
, name
, pat
, buffer
, buflen
,
353 errnop
, herrnop
, ttlp
);
355 if (host_buffer
.buf
!= orig_host_buffer
)
356 free (host_buffer
.buf
);
362 extern enum nss_status
_nss_dns_gethostbyaddr2_r (const void *addr
,
363 socklen_t len
, int af
,
364 struct hostent
*result
,
365 char *buffer
, size_t buflen
,
366 int *errnop
, int *h_errnop
,
368 hidden_proto (_nss_dns_gethostbyaddr2_r
)
371 _nss_dns_gethostbyaddr2_r (const void *addr
, socklen_t len
, int af
,
372 struct hostent
*result
, char *buffer
, size_t buflen
,
373 int *errnop
, int *h_errnop
, int32_t *ttlp
)
375 static const u_char mapped
[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0xff,0xff };
376 static const u_char tunnelled
[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0,0 };
377 static const u_char v6local
[] = { 0,0, 0,1 };
378 const u_char
*uaddr
= (const u_char
*)addr
;
381 char *aliases
[MAX_NR_ALIASES
];
382 unsigned char host_addr
[16]; /* IPv4 or IPv6 */
383 char *h_addr_ptrs
[MAX_NR_ADDRS
+ 1];
385 } *host_data
= (struct host_data
*) buffer
;
391 querybuf
*orig_host_buffer
;
392 char qbuf
[MAXDNAME
+1], *qp
= NULL
;
397 uintptr_t pad
= -(uintptr_t) buffer
% __alignof__ (struct host_data
);
399 buflen
= buflen
> pad
? buflen
- pad
: 0;
401 if (__builtin_expect (buflen
< sizeof (struct host_data
), 0))
404 *h_errnop
= NETDB_INTERNAL
;
405 return NSS_STATUS_TRYAGAIN
;
408 host_data
= (struct host_data
*) buffer
;
410 if (__res_maybe_init (&_res
, 0) == -1)
411 return NSS_STATUS_UNAVAIL
;
413 if (af
== AF_INET6
&& len
== IN6ADDRSZ
414 && (memcmp (uaddr
, mapped
, sizeof mapped
) == 0
415 || (memcmp (uaddr
, tunnelled
, sizeof tunnelled
) == 0
416 && memcmp (&uaddr
[sizeof tunnelled
], v6local
, sizeof v6local
))))
419 addr
+= sizeof mapped
;
420 uaddr
+= sizeof mapped
;
434 *errnop
= EAFNOSUPPORT
;
435 *h_errnop
= NETDB_INTERNAL
;
436 return NSS_STATUS_UNAVAIL
;
440 *errnop
= EAFNOSUPPORT
;
441 *h_errnop
= NETDB_INTERNAL
;
442 return NSS_STATUS_UNAVAIL
;
445 host_buffer
.buf
= orig_host_buffer
= (querybuf
*) alloca (1024);
450 sprintf (qbuf
, "%u.%u.%u.%u.in-addr.arpa", (uaddr
[3] & 0xff),
451 (uaddr
[2] & 0xff), (uaddr
[1] & 0xff), (uaddr
[0] & 0xff));
454 /* Only lookup with the byte string format if the user wants it. */
455 if (__builtin_expect (_res
.options
& RES_USEBSTRING
, 0))
457 qp
= stpcpy (qbuf
, "\\[x");
458 for (n
= 0; n
< IN6ADDRSZ
; ++n
)
459 qp
+= sprintf (qp
, "%02hhx", uaddr
[n
]);
460 strcpy (qp
, "].ip6.arpa");
461 n
= __libc_res_nquery (&_res
, qbuf
, C_IN
, T_PTR
,
462 host_buffer
.buf
->buf
, 1024, &host_buffer
.ptr
,
468 for (n
= IN6ADDRSZ
- 1; n
>= 0; n
--)
470 static const char nibblechar
[16] = "0123456789abcdef";
471 *qp
++ = nibblechar
[uaddr
[n
] & 0xf];
473 *qp
++ = nibblechar
[(uaddr
[n
] >> 4) & 0xf];
476 strcpy(qp
, "ip6.arpa");
483 n
= __libc_res_nquery (&_res
, qbuf
, C_IN
, T_PTR
, host_buffer
.buf
->buf
,
484 1024, &host_buffer
.ptr
, NULL
, NULL
, NULL
);
485 if (n
< 0 && af
== AF_INET6
&& (_res
.options
& RES_NOIP6DOTINT
) == 0)
487 strcpy (qp
, "ip6.int");
488 n
= __libc_res_nquery (&_res
, qbuf
, C_IN
, T_PTR
, host_buffer
.buf
->buf
,
489 host_buffer
.buf
!= orig_host_buffer
490 ? MAXPACKET
: 1024, &host_buffer
.ptr
,
496 __set_errno (olderr
);
497 if (host_buffer
.buf
!= orig_host_buffer
)
498 free (host_buffer
.buf
);
499 return errno
== ECONNREFUSED
? NSS_STATUS_UNAVAIL
: NSS_STATUS_NOTFOUND
;
503 status
= getanswer_r (host_buffer
.buf
, n
, qbuf
, T_PTR
, result
, buffer
, buflen
,
504 errnop
, h_errnop
, 0 /* XXX */, ttlp
, NULL
);
505 if (host_buffer
.buf
!= orig_host_buffer
)
506 free (host_buffer
.buf
);
507 if (status
!= NSS_STATUS_SUCCESS
)
511 This is
not implemented because it is
not possible to use the current
512 source from bind in a multi
-threaded program
.
515 result
->h_addrtype
= af
;
516 result
->h_length
= len
;
517 memcpy (host_data
->host_addr
, addr
, len
);
518 host_data
->h_addr_ptrs
[0] = (char *) host_data
->host_addr
;
519 host_data
->h_addr_ptrs
[1] = NULL
;
521 /* XXX I think this is wrong. Why should an IPv4 address be
522 converted to IPv6 if the user explicitly asked for IPv4? */
523 if (af
== AF_INET
&& (_res
.options
& RES_USE_INET6
))
525 map_v4v6_address ((char *) host_data
->host_addr
,
526 (char *) host_data
->host_addr
);
527 result
->h_addrtype
= AF_INET6
;
528 result
->h_length
= IN6ADDRSZ
;
531 *h_errnop
= NETDB_SUCCESS
;
532 return NSS_STATUS_SUCCESS
;
534 hidden_def (_nss_dns_gethostbyaddr2_r
)
538 _nss_dns_gethostbyaddr_r (const void *addr
, socklen_t len
, int af
,
539 struct hostent
*result
, char *buffer
, size_t buflen
,
540 int *errnop
, int *h_errnop
)
542 return _nss_dns_gethostbyaddr2_r (addr
, len
, af
, result
, buffer
, buflen
,
543 errnop
, h_errnop
, NULL
);
547 static void addrsort (char **ap
, int num
);
550 addrsort (char **ap
, int num
)
554 short aval
[MAX_NR_ADDRS
];
558 if (num
> MAX_NR_ADDRS
)
560 for (i
= 0; i
< num
; i
++, p
++)
562 for (j
= 0 ; (unsigned)j
< _res
.nsort
; j
++)
563 if (_res
.sort_list
[j
].addr
.s_addr
==
564 (((struct in_addr
*)(*p
))->s_addr
& _res
.sort_list
[j
].mask
))
567 if (needsort
== 0 && i
> 0 && j
< aval
[i
-1])
573 while (needsort
++ < num
)
574 for (j
= needsort
- 2; j
>= 0; j
--)
575 if (aval
[j
] > aval
[j
+1])
592 static enum nss_status
593 getanswer_r (const querybuf
*answer
, int anslen
, const char *qname
, int qtype
,
594 struct hostent
*result
, char *buffer
, size_t buflen
,
595 int *errnop
, int *h_errnop
, int map
, int32_t *ttlp
, char **canonp
)
599 char *aliases
[MAX_NR_ALIASES
];
600 unsigned char host_addr
[16]; /* IPv4 or IPv6 */
601 char *h_addr_ptrs
[0];
605 const u_char
*end_of_message
, *cp
;
606 int n
, ancount
, qdcount
;
607 int haveanswer
, had_error
;
608 char *bp
, **ap
, **hap
;
611 int (*name_ok
) (const char *);
612 u_char packtmp
[NS_MAXCDNAME
];
614 uintptr_t pad
= -(uintptr_t) buffer
% __alignof__ (struct host_data
);
616 if (__builtin_expect (buflen
< sizeof (struct host_data
) + pad
, 0))
618 /* The buffer is too small. */
621 *h_errnop
= NETDB_INTERNAL
;
622 return NSS_STATUS_TRYAGAIN
;
624 host_data
= (struct host_data
*) buffer
;
625 linebuflen
= buflen
- sizeof (struct host_data
);
626 if (buflen
- sizeof (struct host_data
) != linebuflen
)
627 linebuflen
= INT_MAX
;
630 result
->h_name
= NULL
;
631 end_of_message
= answer
->buf
+ anslen
;
643 return NSS_STATUS_UNAVAIL
; /* XXX should be abort(); */
647 * find first satisfactory answer
650 ancount
= ntohs (hp
->ancount
);
651 qdcount
= ntohs (hp
->qdcount
);
652 cp
= answer
->buf
+ HFIXEDSZ
;
653 if (__builtin_expect (qdcount
, 1) != 1)
655 *h_errnop
= NO_RECOVERY
;
656 return NSS_STATUS_UNAVAIL
;
658 if (sizeof (struct host_data
) + (ancount
+ 1) * sizeof (char *) >= buflen
)
660 bp
= (char *) &host_data
->h_addr_ptrs
[ancount
+ 1];
661 linebuflen
-= (ancount
+ 1) * sizeof (char *);
663 n
= __ns_name_unpack (answer
->buf
, end_of_message
, cp
,
664 packtmp
, sizeof packtmp
);
665 if (n
!= -1 && __ns_name_ntop (packtmp
, bp
, linebuflen
) == -1)
667 if (__builtin_expect (errno
, 0) == EMSGSIZE
)
673 if (n
> 0 && bp
[0] == '.')
676 if (__builtin_expect (n
< 0 || ((*name_ok
) (bp
) == 0 && (errno
= EBADMSG
)),
680 *h_errnop
= NO_RECOVERY
;
681 return NSS_STATUS_UNAVAIL
;
685 if (qtype
== T_A
|| qtype
== T_AAAA
)
687 /* res_send() has already verified that the query name is the
688 * same as the one we sent; this just gets the expanded name
689 * (i.e., with the succeeding search-domain tacked on).
691 n
= strlen (bp
) + 1; /* for the \0 */
692 if (n
>= MAXHOSTNAMELEN
)
694 *h_errnop
= NO_RECOVERY
;
696 return NSS_STATUS_TRYAGAIN
;
703 /* The qname can be abbreviated, but h_name is now absolute. */
704 qname
= result
->h_name
;
707 ap
= host_data
->aliases
;
709 result
->h_aliases
= host_data
->aliases
;
710 hap
= host_data
->h_addr_ptrs
;
712 result
->h_addr_list
= host_data
->h_addr_ptrs
;
716 while (ancount
-- > 0 && cp
< end_of_message
&& had_error
== 0)
720 n
= __ns_name_unpack (answer
->buf
, end_of_message
, cp
,
721 packtmp
, sizeof packtmp
);
722 if (n
!= -1 && __ns_name_ntop (packtmp
, bp
, linebuflen
) == -1)
724 if (__builtin_expect (errno
, 0) == EMSGSIZE
)
730 if (__builtin_expect (n
< 0 || (*name_ok
) (bp
) == 0, 0))
737 if (__builtin_expect (cp
+ 10 > end_of_message
, 0))
743 type
= __ns_get16 (cp
);
744 cp
+= INT16SZ
; /* type */
745 class = __ns_get16 (cp
);
746 cp
+= INT16SZ
; /* class */
747 int32_t ttl
= __ns_get32 (cp
);
748 cp
+= INT32SZ
; /* TTL */
750 cp
+= INT16SZ
; /* len */
751 if (__builtin_expect (class != C_IN
, 0))
753 /* XXX - debug? syslog? */
755 continue; /* XXX - had_error++ ? */
758 if ((qtype
== T_A
|| qtype
== T_AAAA
) && type
== T_CNAME
)
760 /* A CNAME could also have a TTL entry. */
761 if (ttlp
!= NULL
&& ttl
< *ttlp
)
764 if (ap
>= &host_data
->aliases
[MAX_NR_ALIASES
- 1])
766 n
= dn_expand (answer
->buf
, end_of_message
, cp
, tbuf
, sizeof tbuf
);
767 if (__builtin_expect (n
< 0 || (*name_ok
) (tbuf
) == 0, 0))
775 n
= strlen (bp
) + 1; /* For the \0. */
776 if (__builtin_expect (n
, 0) >= MAXHOSTNAMELEN
)
783 /* Get canonical name. */
784 n
= strlen (tbuf
) + 1; /* For the \0. */
785 if (__builtin_expect (n
> linebuflen
, 0))
787 if (__builtin_expect (n
, 0) >= MAXHOSTNAMELEN
)
793 bp
= __mempcpy (bp
, tbuf
, n
); /* Cannot overflow. */
798 if (qtype
== T_PTR
&& type
== T_CNAME
)
800 n
= dn_expand (answer
->buf
, end_of_message
, cp
, tbuf
, sizeof tbuf
);
801 if (__builtin_expect (n
< 0 || res_dnok (tbuf
) == 0, 0))
807 /* Get canonical name. */
808 n
= strlen (tbuf
) + 1; /* For the \0. */
809 if (__builtin_expect (n
> linebuflen
, 0))
811 if (__builtin_expect (n
, 0) >= MAXHOSTNAMELEN
)
817 bp
= __mempcpy (bp
, tbuf
, n
); /* Cannot overflow. */
821 if (__builtin_expect (type
== T_SIG
, 0)
822 || __builtin_expect (type
== T_KEY
, 0)
823 || __builtin_expect (type
== T_NXT
, 0))
825 /* We don't support DNSSEC yet. For now, ignore the record
826 and send a low priority message to syslog. */
827 syslog (LOG_DEBUG
| LOG_AUTH
,
828 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"",
829 qname
, p_class (C_IN
), p_type(qtype
), p_type (type
));
834 if (type
== T_A
&& qtype
== T_AAAA
&& map
)
836 else if (__builtin_expect (type
!= qtype
, 0))
838 syslog (LOG_NOTICE
| LOG_AUTH
,
839 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"",
840 qname
, p_class (C_IN
), p_type (qtype
), p_type (type
));
842 continue; /* XXX - had_error++ ? */
848 if (__builtin_expect (strcasecmp (tname
, bp
) != 0, 0))
850 syslog (LOG_NOTICE
| LOG_AUTH
, AskedForGot
, qname
, bp
);
852 continue; /* XXX - had_error++ ? */
855 n
= __ns_name_unpack (answer
->buf
, end_of_message
, cp
,
856 packtmp
, sizeof packtmp
);
857 if (n
!= -1 && __ns_name_ntop (packtmp
, bp
, linebuflen
) == -1)
859 if (__builtin_expect (errno
, 0) == EMSGSIZE
)
865 if (__builtin_expect (n
< 0 || res_hnok (bp
) == 0, 0))
870 #if MULTI_PTRS_ARE_ALIASES
874 else if (ap
< &host_data
->aliases
[MAXALIASES
-1])
880 n
= strlen (bp
) + 1; /* for the \0 */
881 if (__builtin_expect (n
, 0) >= MAXHOSTNAMELEN
)
894 n
= strlen (bp
) + 1; /* for the \0 */
895 if (__builtin_expect (n
>= MAXHOSTNAMELEN
, 0))
902 if (map_v4v6_hostent (result
, &bp
, &linebuflen
))
905 *h_errnop
= NETDB_SUCCESS
;
906 return NSS_STATUS_SUCCESS
;
910 if (__builtin_expect (strcasecmp (result
->h_name
, bp
), 0) != 0)
912 syslog (LOG_NOTICE
| LOG_AUTH
, AskedForGot
, result
->h_name
, bp
);
914 continue; /* XXX - had_error++ ? */
916 if (n
!= result
->h_length
)
925 /* We compose a single hostent out of the entire chain of
926 entries, so the TTL of the hostent is essentially the lowest
928 if (ttlp
!= NULL
&& ttl
< *ttlp
)
933 nn
= strlen (bp
) + 1; /* for the \0 */
938 linebuflen
-= sizeof (align
) - ((u_long
) bp
% sizeof (align
));
939 bp
+= sizeof (align
) - ((u_long
) bp
% sizeof (align
));
941 if (__builtin_expect (n
> linebuflen
, 0))
943 bp
= __mempcpy (*hap
++ = bp
, cp
, n
);
958 #if defined RESOLVSORT
960 * Note: we sort even if host can take only one address
961 * in its return structures - should give it the "best"
962 * address in that case, not some random one
964 if (_res
.nsort
&& haveanswer
> 1 && qtype
== T_A
)
965 addrsort (host_data
->h_addr_ptrs
, haveanswer
);
966 #endif /*RESOLVSORT*/
968 if (result
->h_name
== NULL
)
970 n
= strlen (qname
) + 1; /* For the \0. */
973 if (n
>= MAXHOSTNAMELEN
)
976 bp
= __mempcpy (bp
, qname
, n
); /* Cannot overflow. */
981 if (map_v4v6_hostent (result
, &bp
, &linebuflen
))
983 *h_errnop
= NETDB_SUCCESS
;
984 return NSS_STATUS_SUCCESS
;
987 *h_errnop
= NO_RECOVERY
;
989 /* Special case here: if the resolver sent a result but it only
990 contains a CNAME while we are looking for a T_A or T_AAAA record,
991 we fail with NOTFOUND instead of TRYAGAIN. */
992 return ((qtype
== T_A
|| qtype
== T_AAAA
) && ap
!= host_data
->aliases
993 ? NSS_STATUS_NOTFOUND
: NSS_STATUS_TRYAGAIN
);
997 static enum nss_status
998 gaih_getanswer_slice (const querybuf
*answer
, int anslen
, const char *qname
,
999 struct gaih_addrtuple
***patp
,
1000 char **bufferp
, size_t *buflenp
,
1001 int *errnop
, int *h_errnop
, int32_t *ttlp
, int *firstp
)
1003 char *buffer
= *bufferp
;
1004 size_t buflen
= *buflenp
;
1006 struct gaih_addrtuple
**pat
= *patp
;
1007 const HEADER
*hp
= &answer
->hdr
;
1008 int ancount
= ntohs (hp
->ancount
);
1009 int qdcount
= ntohs (hp
->qdcount
);
1010 const u_char
*cp
= answer
->buf
+ HFIXEDSZ
;
1011 const u_char
*end_of_message
= answer
->buf
+ anslen
;
1012 if (__builtin_expect (qdcount
!= 1, 0))
1014 *h_errnop
= NO_RECOVERY
;
1015 return NSS_STATUS_UNAVAIL
;
1018 u_char packtmp
[NS_MAXCDNAME
];
1019 int n
= __ns_name_unpack (answer
->buf
, end_of_message
, cp
,
1020 packtmp
, sizeof packtmp
);
1021 /* We unpack the name to check it for validity. But we do not need
1023 if (n
!= -1 && __ns_name_ntop (packtmp
, buffer
, buflen
) == -1)
1025 if (__builtin_expect (errno
, 0) == EMSGSIZE
)
1029 *h_errnop
= NETDB_INTERNAL
;
1030 return NSS_STATUS_TRYAGAIN
;
1036 if (__builtin_expect (n
< 0 || (res_hnok (buffer
) == 0
1037 && (errno
= EBADMSG
)), 0))
1040 *h_errnop
= NO_RECOVERY
;
1041 return NSS_STATUS_UNAVAIL
;
1048 char *h_name
= NULL
;
1052 return NSS_STATUS_NOTFOUND
;
1054 while (ancount
-- > 0 && cp
< end_of_message
&& had_error
== 0)
1056 n
= __ns_name_unpack (answer
->buf
, end_of_message
, cp
,
1057 packtmp
, sizeof packtmp
);
1059 (h_namelen
= __ns_name_ntop (packtmp
, buffer
, buflen
)) == -1)
1061 if (__builtin_expect (errno
, 0) == EMSGSIZE
)
1066 if (__builtin_expect (n
< 0 || res_hnok (buffer
) == 0, 0))
1071 if (*firstp
&& canon
== NULL
)
1074 buffer
+= h_namelen
;
1075 buflen
-= h_namelen
;
1080 if (__builtin_expect (cp
+ 10 > end_of_message
, 0))
1086 int type
= __ns_get16 (cp
);
1087 cp
+= INT16SZ
; /* type */
1088 int class = __ns_get16 (cp
);
1089 cp
+= INT16SZ
; /* class */
1090 int32_t ttl
= __ns_get32 (cp
);
1091 cp
+= INT32SZ
; /* TTL */
1092 n
= __ns_get16 (cp
);
1093 cp
+= INT16SZ
; /* len */
1101 if (type
== T_CNAME
)
1103 char tbuf
[MAXDNAME
];
1105 /* A CNAME could also have a TTL entry. */
1106 if (ttlp
!= NULL
&& ttl
< *ttlp
)
1109 n
= dn_expand (answer
->buf
, end_of_message
, cp
, tbuf
, sizeof tbuf
);
1110 if (__builtin_expect (n
< 0 || res_hnok (tbuf
) == 0, 0))
1119 /* Reclaim buffer space. */
1120 if (h_name
+ h_namelen
== buffer
)
1123 buflen
+= h_namelen
;
1126 n
= strlen (tbuf
) + 1;
1127 if (__builtin_expect (n
> buflen
, 0))
1129 if (__builtin_expect (n
>= MAXHOSTNAMELEN
, 0))
1136 buffer
= __mempcpy (buffer
, tbuf
, n
);
1143 // We should not see any types other than those explicitly listed
1144 // below. Some types sent by server seem missing, though. Just
1145 // collect the data for now.
1146 if (__builtin_expect (type
!= T_A
&& type
!= T_AAAA
, 0))
1148 if (__builtin_expect (type
== T_SIG
, 0)
1149 || __builtin_expect (type
== T_KEY
, 0)
1150 || __builtin_expect (type
== T_NXT
, 0)
1151 || __builtin_expect (type
== T_PTR
, 0)
1152 || __builtin_expect (type
== T_DNAME
, 0))
1155 /* We don't support DNSSEC yet. For now, ignore the record
1156 and send a low priority message to syslog.
1158 We also don't expect T_PTR or T_DNAME messages. */
1159 syslog (LOG_DEBUG
| LOG_AUTH
,
1160 "getaddrinfo*.gaih_getanswer: got type \"%s\"",
1165 if (type
!= T_A
&& type
!= T_AAAA
)
1170 uintptr_t pad
= (-(uintptr_t) buffer
1171 % __alignof__ (struct gaih_addrtuple
));
1173 buflen
= buflen
> pad
? buflen
- pad
: 0;
1175 if (__builtin_expect (buflen
< sizeof (struct gaih_addrtuple
),
1179 *pat
= (struct gaih_addrtuple
*) buffer
;
1180 buffer
+= sizeof (struct gaih_addrtuple
);
1181 buflen
-= sizeof (struct gaih_addrtuple
);
1184 (*pat
)->name
= NULL
;
1185 (*pat
)->next
= NULL
;
1189 /* We compose a single hostent out of the entire chain of
1190 entries, so the TTL of the hostent is essentially the lowest
1191 TTL in the chain. */
1192 if (ttlp
!= NULL
&& ttl
< *ttlp
)
1195 (*pat
)->name
= canon
?: h_name
;
1200 (*pat
)->family
= type
== T_A
? AF_INET
: AF_INET6
;
1201 if (__builtin_expect ((type
== T_A
&& n
!= INADDRSZ
)
1202 || (type
== T_AAAA
&& n
!= IN6ADDRSZ
), 0))
1207 memcpy ((*pat
)->addr
, cp
, n
);
1209 (*pat
)->scopeid
= 0;
1211 pat
= &((*pat
)->next
);
1222 *h_errnop
= NETDB_SUCCESS
;
1223 return NSS_STATUS_SUCCESS
;
1226 /* Special case here: if the resolver sent a result but it only
1227 contains a CNAME while we are looking for a T_A or T_AAAA record,
1228 we fail with NOTFOUND instead of TRYAGAIN. */
1229 return canon
== NULL
? NSS_STATUS_TRYAGAIN
: NSS_STATUS_NOTFOUND
;
1233 static enum nss_status
1234 gaih_getanswer (const querybuf
*answer1
, int anslen1
, const querybuf
*answer2
,
1235 int anslen2
, const char *qname
,
1236 struct gaih_addrtuple
**pat
, char *buffer
, size_t buflen
,
1237 int *errnop
, int *h_errnop
, int32_t *ttlp
)
1241 enum nss_status status
= NSS_STATUS_NOTFOUND
;
1244 status
= gaih_getanswer_slice(answer1
, anslen1
, qname
,
1245 &pat
, &buffer
, &buflen
,
1246 errnop
, h_errnop
, ttlp
,
1248 if ((status
== NSS_STATUS_SUCCESS
|| status
== NSS_STATUS_NOTFOUND
1249 || (status
== NSS_STATUS_TRYAGAIN
1250 /* We want to look at the second answer in case of an
1251 NSS_STATUS_TRYAGAIN only if the error is non-recoverable, i.e.
1252 *h_errnop is NO_RECOVERY. If not, and if the failure was due to
1253 an insufficient buffer (ERANGE), then we need to drop the results
1254 and pass on the NSS_STATUS_TRYAGAIN to the caller so that it can
1255 repeat the query with a larger buffer. */
1256 && (*errnop
!= ERANGE
|| *h_errnop
== NO_RECOVERY
)))
1257 && answer2
!= NULL
&& anslen2
> 0)
1259 enum nss_status status2
= gaih_getanswer_slice(answer2
, anslen2
, qname
,
1260 &pat
, &buffer
, &buflen
,
1261 errnop
, h_errnop
, ttlp
,
1263 if (status
!= NSS_STATUS_SUCCESS
&& status2
!= NSS_STATUS_NOTFOUND
)