1 /* Copyright (C) 1996-2004, 2007, 2008, 2009 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, write to the Free
17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
20 /* Parts of this file are plain copies of the file `gethtnamadr.c' from
21 the bind package and it has the following copyright. */
24 * ++Copyright++ 1985, 1988, 1993
26 * Copyright (c) 1985, 1988, 1993
27 * The Regents of the University of California. All rights reserved.
29 * Redistribution and use in source and binary forms, with or without
30 * modification, are permitted provided that the following conditions
32 * 1. Redistributions of source code must retain the above copyright
33 * notice, this list of conditions and the following disclaimer.
34 * 2. Redistributions in binary form must reproduce the above copyright
35 * notice, this list of conditions and the following disclaimer in the
36 * documentation and/or other materials provided with the distribution.
37 * 4. Neither the name of the University nor the names of its contributors
38 * may be used to endorse or promote products derived from this software
39 * without specific prior written permission.
41 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
53 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
55 * Permission to use, copy, modify, and distribute this software for any
56 * purpose with or without fee is hereby granted, provided that the above
57 * copyright notice and this permission notice appear in all copies, and that
58 * the name of Digital Equipment Corporation not be used in advertising or
59 * publicity pertaining to distribution of the document or software without
60 * specific, written prior permission.
62 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
63 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
64 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
65 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
66 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
67 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
68 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
82 #include <sys/syslog.h>
86 /* Get implementation for some internal functions. */
87 #include <resolv/mapv4v6addr.h>
88 #include <resolv/mapv4v6hostent.h>
92 /* Maximum number of aliases we allow. */
93 #define MAX_NR_ALIASES 48
94 #define MAX_NR_ADDRS 48
97 # define MAXPACKET PACKETSZ
99 # define MAXPACKET 65536
101 /* As per RFC 1034 and 1035 a host name cannot exceed 255 octets in length. */
102 #ifdef MAXHOSTNAMELEN
103 # undef MAXHOSTNAMELEN
105 #define MAXHOSTNAMELEN 256
107 static const char AskedForGot[] = "\
108 gethostby*.getanswer: asked for \"%s\", got \"%s\"";
111 /* We need this time later. */
112 typedef union querybuf
115 u_char buf[MAXPACKET];
118 /* These functions are defined in res_comp.c. */
119 #define NS_MAXCDNAME 255 /* maximum compressed domain name */
120 extern int __ns_name_ntop (const u_char *, char *, size_t);
121 extern int __ns_name_unpack (const u_char *, const u_char *,
122 const u_char *, u_char *, size_t);
125 static enum nss_status getanswer_r (const querybuf *answer, int anslen,
126 const char *qname, int qtype,
127 struct hostent *result, char *buffer,
128 size_t buflen, int *errnop, int *h_errnop,
129 int map, int32_t *ttlp, char **canonp);
131 static enum nss_status gaih_getanswer (const querybuf *answer1, int anslen1,
132 const querybuf *answer2, int anslen2,
134 struct gaih_addrtuple **pat,
135 char *buffer, size_t buflen,
136 int *errnop, int *h_errnop,
139 extern enum nss_status _nss_dns_gethostbyname3_r (const char *name, int af,
140 struct hostent *result,
141 char *buffer, size_t buflen,
142 int *errnop, int *h_errnop,
145 hidden_proto (_nss_dns_gethostbyname3_r)
148 _nss_dns_gethostbyname3_r (const char *name, int af, struct hostent *result,
149 char *buffer, size_t buflen, int *errnop,
150 int *h_errnop, int32_t *ttlp, char **canonp)
157 querybuf *orig_host_buffer;
158 char tmp[NS_MAXDNAME];
163 enum nss_status status;
165 if (__res_maybe_init (&_res, 0) == -1)
166 return NSS_STATUS_UNAVAIL;
179 *errnop = EAFNOSUPPORT;
180 return NSS_STATUS_UNAVAIL;
183 result->h_addrtype = af;
184 result->h_length = size;
187 * if there aren't any dots, it could be a user-level alias.
188 * this is also done in res_query() since we are not the only
189 * function that looks up host names.
191 if (strchr (name, '.') == NULL
192 && (cp = res_hostalias (&_res, name, tmp, sizeof (tmp))) != NULL)
195 host_buffer.buf = orig_host_buffer = (querybuf *) alloca (1024);
197 n = __libc_res_nsearch (&_res, name, C_IN, type, host_buffer.buf->buf,
198 1024, &host_buffer.ptr, NULL, NULL, NULL);
203 status = NSS_STATUS_TRYAGAIN;
207 status = (errno == ECONNREFUSED
208 ? NSS_STATUS_UNAVAIL : NSS_STATUS_NOTFOUND);
210 if (h_errno == TRY_AGAIN)
213 __set_errno (olderr);
215 /* If we are looking for a IPv6 address and mapping is enabled
216 by having the RES_USE_INET6 bit in _res.options set, we try
218 if (af == AF_INET6 && (_res.options & RES_USE_INET6))
219 n = __libc_res_nsearch (&_res, name, C_IN, T_A, host_buffer.buf->buf,
220 host_buffer.buf != orig_host_buffer
221 ? MAXPACKET : 1024, &host_buffer.ptr,
226 if (host_buffer.buf != orig_host_buffer)
227 free (host_buffer.buf);
233 result->h_addrtype = AF_INET;
234 result->h_length = INADDRSZ;
237 status = getanswer_r (host_buffer.buf, n, name, type, result, buffer, buflen,
238 errnop, h_errnop, map, ttlp, canonp);
239 if (host_buffer.buf != orig_host_buffer)
240 free (host_buffer.buf);
243 hidden_def (_nss_dns_gethostbyname3_r)
247 _nss_dns_gethostbyname2_r (const char *name, int af, struct hostent *result,
248 char *buffer, size_t buflen, int *errnop,
251 return _nss_dns_gethostbyname3_r (name, af, result, buffer, buflen, errnop,
252 h_errnop, NULL, NULL);
257 _nss_dns_gethostbyname_r (const char *name, struct hostent *result,
258 char *buffer, size_t buflen, int *errnop,
261 enum nss_status status = NSS_STATUS_NOTFOUND;
263 if (_res.options & RES_USE_INET6)
264 status = _nss_dns_gethostbyname3_r (name, AF_INET6, result, buffer,
265 buflen, errnop, h_errnop, NULL, NULL);
266 if (status == NSS_STATUS_NOTFOUND)
267 status = _nss_dns_gethostbyname3_r (name, AF_INET, result, buffer,
268 buflen, errnop, h_errnop, NULL, NULL);
275 _nss_dns_gethostbyname4_r (const char *name, struct gaih_addrtuple **pat,
276 char *buffer, size_t buflen, int *errnop,
277 int *herrnop, int32_t *ttlp)
279 if (__res_maybe_init (&_res, 0) == -1)
280 return NSS_STATUS_UNAVAIL;
283 * if there aren't any dots, it could be a user-level alias.
284 * this is also done in res_query() since we are not the only
285 * function that looks up host names.
287 if (strchr (name, '.') == NULL)
289 char *tmp = alloca (NS_MAXDNAME);
290 const char *cp = res_hostalias (&_res, name, tmp, NS_MAXDNAME);
300 querybuf *orig_host_buffer;
301 host_buffer.buf = orig_host_buffer = (querybuf *) alloca (2048);
302 u_char *ans2p = NULL;
307 enum nss_status status;
308 int n = __libc_res_nsearch (&_res, name, C_IN, T_UNSPEC,
309 host_buffer.buf->buf, 2048, &host_buffer.ptr,
310 &ans2p, &nans2p, &resplen2);
315 status = NSS_STATUS_TRYAGAIN;
319 status = (errno == ECONNREFUSED
320 ? NSS_STATUS_UNAVAIL : NSS_STATUS_NOTFOUND);
322 if (h_errno == TRY_AGAIN)
325 __set_errno (olderr);
327 if (host_buffer.buf != orig_host_buffer)
328 free (host_buffer.buf);
333 status = gaih_getanswer(host_buffer.buf, n, (const querybuf *) ans2p,
334 resplen2, name, pat, buffer, buflen,
335 errnop, herrnop, ttlp);
337 if (host_buffer.buf != orig_host_buffer)
338 free (host_buffer.buf);
344 extern enum nss_status _nss_dns_gethostbyaddr2_r (const void *addr,
345 socklen_t len, int af,
346 struct hostent *result,
347 char *buffer, size_t buflen,
348 int *errnop, int *h_errnop,
350 hidden_proto (_nss_dns_gethostbyaddr2_r)
353 _nss_dns_gethostbyaddr2_r (const void *addr, socklen_t len, int af,
354 struct hostent *result, char *buffer, size_t buflen,
355 int *errnop, int *h_errnop, int32_t *ttlp)
357 static const u_char mapped[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0xff,0xff };
358 static const u_char tunnelled[] = { 0,0, 0,0, 0,0, 0,0, 0,0, 0,0 };
359 static const u_char v6local[] = { 0,0, 0,1 };
360 const u_char *uaddr = (const u_char *)addr;
363 char *aliases[MAX_NR_ALIASES];
364 unsigned char host_addr[16]; /* IPv4 or IPv6 */
365 char *h_addr_ptrs[MAX_NR_ADDRS + 1];
367 } *host_data = (struct host_data *) buffer;
373 querybuf *orig_host_buffer;
374 char qbuf[MAXDNAME+1], *qp = NULL;
379 uintptr_t pad = -(uintptr_t) buffer % __alignof__ (struct host_data);
381 buflen = buflen > pad ? buflen - pad : 0;
383 if (__builtin_expect (buflen < sizeof (struct host_data), 0))
386 *h_errnop = NETDB_INTERNAL;
387 return NSS_STATUS_TRYAGAIN;
390 host_data = (struct host_data *) buffer;
392 if (__res_maybe_init (&_res, 0) == -1)
393 return NSS_STATUS_UNAVAIL;
395 if (af == AF_INET6 && len == IN6ADDRSZ
396 && (memcmp (uaddr, mapped, sizeof mapped) == 0
397 || (memcmp (uaddr, tunnelled, sizeof tunnelled) == 0
398 && memcmp (&uaddr[sizeof tunnelled], v6local, sizeof v6local))))
401 addr += sizeof mapped;
402 uaddr += sizeof mapped;
416 *errnop = EAFNOSUPPORT;
417 *h_errnop = NETDB_INTERNAL;
418 return NSS_STATUS_UNAVAIL;
422 *errnop = EAFNOSUPPORT;
423 *h_errnop = NETDB_INTERNAL;
424 return NSS_STATUS_UNAVAIL;
427 host_buffer.buf = orig_host_buffer = (querybuf *) alloca (1024);
432 sprintf (qbuf, "%u.%u.%u.%u.in-addr.arpa", (uaddr[3] & 0xff),
433 (uaddr[2] & 0xff), (uaddr[1] & 0xff), (uaddr[0] & 0xff));
436 /* Only lookup with the byte string format if the user wants it. */
437 if (__builtin_expect (_res.options & RES_USEBSTRING, 0))
439 qp = stpcpy (qbuf, "\\[x");
440 for (n = 0; n < IN6ADDRSZ; ++n)
441 qp += sprintf (qp, "%02hhx", uaddr[n]);
442 strcpy (qp, "].ip6.arpa");
443 n = __libc_res_nquery (&_res, qbuf, C_IN, T_PTR,
444 host_buffer.buf->buf, 1024, &host_buffer.ptr,
450 for (n = IN6ADDRSZ - 1; n >= 0; n--)
452 static const char nibblechar[16] = "0123456789abcdef";
453 *qp++ = nibblechar[uaddr[n] & 0xf];
455 *qp++ = nibblechar[(uaddr[n] >> 4) & 0xf];
458 strcpy(qp, "ip6.arpa");
465 n = __libc_res_nquery (&_res, qbuf, C_IN, T_PTR, host_buffer.buf->buf,
466 1024, &host_buffer.ptr, NULL, NULL, NULL);
467 if (n < 0 && af == AF_INET6 && (_res.options & RES_NOIP6DOTINT) == 0)
469 strcpy (qp, "ip6.int");
470 n = __libc_res_nquery (&_res, qbuf, C_IN, T_PTR, host_buffer.buf->buf,
471 host_buffer.buf != orig_host_buffer
472 ? MAXPACKET : 1024, &host_buffer.ptr,
478 __set_errno (olderr);
479 if (host_buffer.buf != orig_host_buffer)
480 free (host_buffer.buf);
481 return errno == ECONNREFUSED ? NSS_STATUS_UNAVAIL : NSS_STATUS_NOTFOUND;
485 status = getanswer_r (host_buffer.buf, n, qbuf, T_PTR, result, buffer, buflen,
486 errnop, h_errnop, 0 /* XXX */, ttlp, NULL);
487 if (host_buffer.buf != orig_host_buffer)
488 free (host_buffer.buf);
489 if (status != NSS_STATUS_SUCCESS)
493 This is not implemented because it is not possible to use the current
494 source from bind in a multi-threaded program.
497 result->h_addrtype = af;
498 result->h_length = len;
499 memcpy (host_data->host_addr, addr, len);
500 host_data->h_addr_ptrs[0] = (char *) host_data->host_addr;
501 host_data->h_addr_ptrs[1] = NULL;
503 /* XXX I think this is wrong. Why should an IPv4 address be
504 converted to IPv6 if the user explicitly asked for IPv4? */
505 if (af == AF_INET && (_res.options & RES_USE_INET6))
507 map_v4v6_address ((char *) host_data->host_addr,
508 (char *) host_data->host_addr);
509 result->h_addrtype = AF_INET6;
510 result->h_length = IN6ADDRSZ;
513 *h_errnop = NETDB_SUCCESS;
514 return NSS_STATUS_SUCCESS;
516 hidden_def (_nss_dns_gethostbyaddr2_r)
520 _nss_dns_gethostbyaddr_r (const void *addr, socklen_t len, int af,
521 struct hostent *result, char *buffer, size_t buflen,
522 int *errnop, int *h_errnop)
524 return _nss_dns_gethostbyaddr2_r (addr, len, af, result, buffer, buflen,
525 errnop, h_errnop, NULL);
529 static void addrsort (char **ap, int num);
532 addrsort (char **ap, int num)
536 short aval[MAX_NR_ADDRS];
540 if (num > MAX_NR_ADDRS)
542 for (i = 0; i < num; i++, p++)
544 for (j = 0 ; (unsigned)j < _res.nsort; j++)
545 if (_res.sort_list[j].addr.s_addr ==
546 (((struct in_addr *)(*p))->s_addr & _res.sort_list[j].mask))
549 if (needsort == 0 && i > 0 && j < aval[i-1])
555 while (needsort++ < num)
556 for (j = needsort - 2; j >= 0; j--)
557 if (aval[j] > aval[j+1])
574 static enum nss_status
575 getanswer_r (const querybuf *answer, int anslen, const char *qname, int qtype,
576 struct hostent *result, char *buffer, size_t buflen,
577 int *errnop, int *h_errnop, int map, int32_t *ttlp, char **canonp)
581 char *aliases[MAX_NR_ALIASES];
582 unsigned char host_addr[16]; /* IPv4 or IPv6 */
583 char *h_addr_ptrs[0];
586 register const HEADER *hp;
587 const u_char *end_of_message, *cp;
588 int n, ancount, qdcount;
589 int haveanswer, had_error;
590 char *bp, **ap, **hap;
593 int (*name_ok) (const char *);
594 u_char packtmp[NS_MAXCDNAME];
597 uintptr_t pad = -(uintptr_t) buffer % __alignof__ (struct host_data);
599 if (__builtin_expect (buflen < sizeof (struct host_data) + pad, 0))
601 /* The buffer is too small. */
604 *h_errnop = NETDB_INTERNAL;
605 return NSS_STATUS_TRYAGAIN;
607 host_data = (struct host_data *) buffer;
608 linebuflen = buflen - sizeof (struct host_data);
609 if (buflen - sizeof (struct host_data) != linebuflen)
610 linebuflen = INT_MAX;
613 result->h_name = NULL;
614 end_of_message = answer->buf + anslen;
626 return NSS_STATUS_UNAVAIL; /* XXX should be abort(); */
630 * find first satisfactory answer
633 ancount = ntohs (hp->ancount);
634 qdcount = ntohs (hp->qdcount);
635 cp = answer->buf + HFIXEDSZ;
636 if (__builtin_expect (qdcount, 1) != 1)
638 *h_errnop = NO_RECOVERY;
639 return NSS_STATUS_UNAVAIL;
641 if (sizeof (struct host_data) + (ancount + 1) * sizeof (char *) >= buflen)
643 bp = (char *) &host_data->h_addr_ptrs[ancount + 1];
644 linebuflen -= (ancount + 1) * sizeof (char *);
646 n = __ns_name_unpack (answer->buf, end_of_message, cp,
647 packtmp, sizeof packtmp);
648 if (n != -1 && __ns_name_ntop (packtmp, bp, linebuflen) == -1)
650 if (__builtin_expect (errno, 0) == EMSGSIZE)
656 if (n > 0 && bp[0] == '.')
659 if (__builtin_expect (n < 0 || ((*name_ok) (bp) == 0 && (errno = EBADMSG)),
663 *h_errnop = NO_RECOVERY;
664 return NSS_STATUS_UNAVAIL;
668 if (qtype == T_A || qtype == T_AAAA)
670 /* res_send() has already verified that the query name is the
671 * same as the one we sent; this just gets the expanded name
672 * (i.e., with the succeeding search-domain tacked on).
674 n = strlen (bp) + 1; /* for the \0 */
675 if (n >= MAXHOSTNAMELEN)
677 *h_errnop = NO_RECOVERY;
679 return NSS_STATUS_TRYAGAIN;
686 /* The qname can be abbreviated, but h_name is now absolute. */
687 qname = result->h_name;
690 ap = host_data->aliases;
692 result->h_aliases = host_data->aliases;
693 hap = host_data->h_addr_ptrs;
695 result->h_addr_list = host_data->h_addr_ptrs;
699 while (ancount-- > 0 && cp < end_of_message && had_error == 0)
703 n = __ns_name_unpack (answer->buf, end_of_message, cp,
704 packtmp, sizeof packtmp);
705 if (n != -1 && __ns_name_ntop (packtmp, bp, linebuflen) == -1)
707 if (__builtin_expect (errno, 0) == EMSGSIZE)
713 if (__builtin_expect (n < 0 || (*name_ok) (bp) == 0, 0))
720 if (__builtin_expect (cp + 10 > end_of_message, 0))
726 type = __ns_get16 (cp);
727 cp += INT16SZ; /* type */
728 class = __ns_get16 (cp);
729 cp += INT16SZ; /* class */
730 ttl = __ns_get32 (cp);
731 cp += INT32SZ; /* TTL */
733 cp += INT16SZ; /* len */
734 if (__builtin_expect (class != C_IN, 0))
736 /* XXX - debug? syslog? */
738 continue; /* XXX - had_error++ ? */
741 if ((qtype == T_A || qtype == T_AAAA) && type == T_CNAME)
743 if (ap >= &host_data->aliases[MAX_NR_ALIASES - 1])
745 n = dn_expand (answer->buf, end_of_message, cp, tbuf, sizeof tbuf);
746 if (__builtin_expect (n < 0 || (*name_ok) (tbuf) == 0, 0))
754 n = strlen (bp) + 1; /* For the \0. */
755 if (__builtin_expect (n, 0) >= MAXHOSTNAMELEN)
762 /* Get canonical name. */
763 n = strlen (tbuf) + 1; /* For the \0. */
764 if (__builtin_expect (n > linebuflen, 0))
766 if (__builtin_expect (n, 0) >= MAXHOSTNAMELEN)
772 bp = __mempcpy (bp, tbuf, n); /* Cannot overflow. */
777 if (qtype == T_PTR && type == T_CNAME)
779 n = dn_expand (answer->buf, end_of_message, cp, tbuf, sizeof tbuf);
780 if (__builtin_expect (n < 0 || res_dnok (tbuf) == 0, 0))
786 /* Get canonical name. */
787 n = strlen (tbuf) + 1; /* For the \0. */
788 if (__builtin_expect (n > linebuflen, 0))
790 if (__builtin_expect (n, 0) >= MAXHOSTNAMELEN)
796 bp = __mempcpy (bp, tbuf, n); /* Cannot overflow. */
800 if (__builtin_expect (type == T_SIG, 0)
801 || __builtin_expect (type == T_KEY, 0)
802 || __builtin_expect (type == T_NXT, 0))
804 /* We don't support DNSSEC yet. For now, ignore the record
805 and send a low priority message to syslog. */
806 syslog (LOG_DEBUG | LOG_AUTH,
807 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"",
808 qname, p_class (C_IN), p_type(qtype), p_type (type));
813 if (type == T_A && qtype == T_AAAA && map)
815 else if (__builtin_expect (type != qtype, 0))
817 syslog (LOG_NOTICE | LOG_AUTH,
818 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"",
819 qname, p_class (C_IN), p_type (qtype), p_type (type));
821 continue; /* XXX - had_error++ ? */
827 if (__builtin_expect (strcasecmp (tname, bp) != 0, 0))
829 syslog (LOG_NOTICE | LOG_AUTH, AskedForGot, qname, bp);
831 continue; /* XXX - had_error++ ? */
834 n = __ns_name_unpack (answer->buf, end_of_message, cp,
835 packtmp, sizeof packtmp);
836 if (n != -1 && __ns_name_ntop (packtmp, bp, linebuflen) == -1)
838 if (__builtin_expect (errno, 0) == EMSGSIZE)
844 if (__builtin_expect (n < 0 || res_hnok (bp) == 0, 0))
849 #if MULTI_PTRS_ARE_ALIASES
853 else if (ap < &host_data->aliases[MAXALIASES-1])
859 n = strlen (bp) + 1; /* for the \0 */
860 if (__builtin_expect (n, 0) >= MAXHOSTNAMELEN)
873 n = strlen (bp) + 1; /* for the \0 */
874 if (__builtin_expect (n >= MAXHOSTNAMELEN, 0))
881 map_v4v6_hostent (result, &bp, &linebuflen);
883 *h_errnop = NETDB_SUCCESS;
884 return NSS_STATUS_SUCCESS;
888 if (__builtin_expect (strcasecmp (result->h_name, bp), 0) != 0)
890 syslog (LOG_NOTICE | LOG_AUTH, AskedForGot, result->h_name, bp);
892 continue; /* XXX - had_error++ ? */
894 if (n != result->h_length)
903 if (ttlp != NULL && ttl != 0)
908 nn = strlen (bp) + 1; /* for the \0 */
913 linebuflen -= sizeof (align) - ((u_long) bp % sizeof (align));
914 bp += sizeof (align) - ((u_long) bp % sizeof (align));
916 if (__builtin_expect (n > linebuflen, 0))
918 bp = __mempcpy (*hap++ = bp, cp, n);
933 #if defined RESOLVSORT
935 * Note: we sort even if host can take only one address
936 * in its return structures - should give it the "best"
937 * address in that case, not some random one
939 if (_res.nsort && haveanswer > 1 && qtype == T_A)
940 addrsort (host_data->h_addr_ptrs, haveanswer);
941 #endif /*RESOLVSORT*/
943 if (result->h_name == NULL)
945 n = strlen (qname) + 1; /* For the \0. */
948 if (n >= MAXHOSTNAMELEN)
951 bp = __mempcpy (bp, qname, n); /* Cannot overflow. */
956 map_v4v6_hostent (result, &bp, &linebuflen);
957 *h_errnop = NETDB_SUCCESS;
958 return NSS_STATUS_SUCCESS;
961 *h_errnop = NO_RECOVERY;
963 /* Special case here: if the resolver sent a result but it only
964 contains a CNAME while we are looking for a T_A or T_AAAA record,
965 we fail with NOTFOUND instead of TRYAGAIN. */
966 return ((qtype == T_A || qtype == T_AAAA) && ap != host_data->aliases
967 ? NSS_STATUS_NOTFOUND : NSS_STATUS_TRYAGAIN);
971 static enum nss_status
972 gaih_getanswer_slice (const querybuf *answer, int anslen, const char *qname,
973 struct gaih_addrtuple ***patp,
974 char **bufferp, size_t *buflenp,
975 int *errnop, int *h_errnop, int32_t *ttlp, int *firstp)
977 char *buffer = *bufferp;
978 size_t buflen = *buflenp;
980 struct gaih_addrtuple **pat = *patp;
981 const HEADER *hp = &answer->hdr;
982 int ancount = ntohs (hp->ancount);
983 int qdcount = ntohs (hp->qdcount);
984 const u_char *cp = answer->buf + HFIXEDSZ;
985 const u_char *end_of_message = answer->buf + anslen;
986 if (__builtin_expect (qdcount != 1, 0))
988 *h_errnop = NO_RECOVERY;
989 return NSS_STATUS_UNAVAIL;
992 u_char packtmp[NS_MAXCDNAME];
993 int n = __ns_name_unpack (answer->buf, end_of_message, cp,
994 packtmp, sizeof packtmp);
995 /* We unpack the name to check it for validity. But we do not need
997 if (n != -1 && __ns_name_ntop (packtmp, buffer, buflen) == -1)
999 if (__builtin_expect (errno, 0) == EMSGSIZE)
1003 *h_errnop = NETDB_INTERNAL;
1004 return NSS_STATUS_TRYAGAIN;
1010 if (__builtin_expect (n < 0 || (res_hnok (buffer) == 0
1011 && (errno = EBADMSG)), 0))
1014 *h_errnop = NO_RECOVERY;
1015 return NSS_STATUS_UNAVAIL;
1022 char *h_name = NULL;
1026 return NSS_STATUS_NOTFOUND;
1028 while (ancount-- > 0 && cp < end_of_message && had_error == 0)
1030 n = __ns_name_unpack (answer->buf, end_of_message, cp,
1031 packtmp, sizeof packtmp);
1033 (h_namelen = __ns_name_ntop (packtmp, buffer, buflen)) == -1)
1035 if (__builtin_expect (errno, 0) == EMSGSIZE)
1040 if (__builtin_expect (n < 0 || res_hnok (buffer) == 0, 0))
1048 buffer += h_namelen;
1049 buflen -= h_namelen;
1054 if (__builtin_expect (cp + 10 > end_of_message, 0))
1060 int type = __ns_get16 (cp);
1061 cp += INT16SZ; /* type */
1062 int class = __ns_get16 (cp);
1063 cp += INT16SZ; /* class */
1064 int32_t ttl = __ns_get32 (cp);
1065 cp += INT32SZ; /* TTL */
1066 n = __ns_get16 (cp);
1067 cp += INT16SZ; /* len */
1075 if (type == T_CNAME)
1077 char tbuf[MAXDNAME];
1078 n = dn_expand (answer->buf, end_of_message, cp, tbuf, sizeof tbuf);
1079 if (__builtin_expect (n < 0 || res_hnok (tbuf) == 0, 0))
1088 /* Reclaim buffer space. */
1089 if (h_name + h_namelen == buffer)
1092 buflen += h_namelen;
1095 n = strlen (tbuf) + 1;
1096 if (__builtin_expect (n > buflen, 0))
1098 if (__builtin_expect (n >= MAXHOSTNAMELEN, 0))
1105 buffer = __mempcpy (buffer, tbuf, n);
1112 // We should not see any types other than those explicitly listed
1113 // below. Some types sent by server seem missing, though. Just
1114 // collect the data for now.
1115 if (__builtin_expect (type != T_A && type != T_AAAA, 0))
1117 if (__builtin_expect (type == T_SIG, 0)
1118 || __builtin_expect (type == T_KEY, 0)
1119 || __builtin_expect (type == T_NXT, 0)
1120 || __builtin_expect (type == T_PTR, 0)
1121 || __builtin_expect (type == T_DNAME, 0))
1124 /* We don't support DNSSEC yet. For now, ignore the record
1125 and send a low priority message to syslog.
1127 We also don't expect T_PTR or T_DNAME messages. */
1128 syslog (LOG_DEBUG | LOG_AUTH,
1129 "getaddrinfo*.gaih_getanswer: got type \"%s\"",
1134 if (type != T_A && type != T_AAAA)
1139 uintptr_t pad = (-(uintptr_t) buffer
1140 % __alignof__ (struct gaih_addrtuple));
1142 buflen = buflen > pad ? buflen - pad : 0;
1144 if (__builtin_expect (buflen < sizeof (struct gaih_addrtuple),
1148 *pat = (struct gaih_addrtuple *) buffer;
1149 buffer += sizeof (struct gaih_addrtuple);
1150 buflen -= sizeof (struct gaih_addrtuple);
1153 (*pat)->name = NULL;
1154 (*pat)->next = NULL;
1158 if (ttl != 0 && ttlp != NULL)
1163 (*pat)->name = canon;
1165 /* Reclaim buffer space. */
1166 if (h_name + h_namelen == buffer)
1169 buflen += h_namelen;
1173 (*pat)->name = h_name;
1178 (*pat)->family = type == T_A ? AF_INET : AF_INET6;
1179 if (__builtin_expect ((type == T_A && n != INADDRSZ)
1180 || (type == T_AAAA && n != IN6ADDRSZ), 0))
1185 memcpy ((*pat)->addr, cp, n);
1187 (*pat)->scopeid = 0;
1189 pat = &((*pat)->next);
1200 *h_errnop = NETDB_SUCCESS;
1201 return NSS_STATUS_SUCCESS;
1204 /* Special case here: if the resolver sent a result but it only
1205 contains a CNAME while we are looking for a T_A or T_AAAA record,
1206 we fail with NOTFOUND instead of TRYAGAIN. */
1207 return canon == NULL ? NSS_STATUS_TRYAGAIN : NSS_STATUS_NOTFOUND;
1211 static enum nss_status
1212 gaih_getanswer (const querybuf *answer1, int anslen1, const querybuf *answer2,
1213 int anslen2, const char *qname,
1214 struct gaih_addrtuple **pat, char *buffer, size_t buflen,
1215 int *errnop, int *h_errnop, int32_t *ttlp)
1219 enum nss_status status = NSS_STATUS_NOTFOUND;
1222 status = gaih_getanswer_slice(answer1, anslen1, qname,
1223 &pat, &buffer, &buflen,
1224 errnop, h_errnop, ttlp,
1226 if ((status == NSS_STATUS_SUCCESS || status == NSS_STATUS_NOTFOUND
1227 || (status == NSS_STATUS_TRYAGAIN
1228 && (errno != ERANGE || *h_errnop != NO_RECOVERY)))
1229 && answer2 != NULL && anslen2 > 0)
1231 enum nss_status status2 = gaih_getanswer_slice(answer2, anslen2, qname,
1232 &pat, &buffer, &buflen,
1233 errnop, h_errnop, ttlp,
1235 if (status != NSS_STATUS_SUCCESS && status2 != NSS_STATUS_NOTFOUND)