1 /* $NetBSD: sethostent.c,v 1.20 2014/03/17 13:24:23 christos Exp $ */
2
3 /*
4 * Copyright (c) 1985, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 #if defined(LIBC_SCCS) && !defined(lint)
34 #if 0
35 static char sccsid[] = "@(#)sethostent.c 8.1 (Berkeley) 6/4/93";
36 static char rcsid[] = "Id: sethostent.c,v 8.5 1996/09/28 06:51:07 vixie Exp ";
37 #else
38 __RCSID("$NetBSD: sethostent.c,v 1.20 2014/03/17 13:24:23 christos Exp $");
39 #endif
40 #endif /* LIBC_SCCS and not lint */
41
42 #include "namespace.h"
43 #include <sys/param.h>
44 #include <netinet/in.h>
45 #include <arpa/nameser.h>
46 #include <arpa/inet.h>
47 #include <assert.h>
48 #include <string.h>
49 #include <nsswitch.h>
50 #include <netdb.h>
51 #include <resolv.h>
52 #include <errno.h>
53 #include <stdlib.h>
54
55 #include "hostent.h"
56 #include "resolv_private.h"
57
58 #define ALIGNBYTES (sizeof(uintptr_t) - 1)
59 #define ALIGN(p) (((uintptr_t)(p) + ALIGNBYTES) &~ ALIGNBYTES)
60
61 #ifndef _REENTRANT
62 void res_close(void);
63 #endif
64
65 static struct hostent *_hf_gethtbyname2(const char *, int, struct getnamaddr *);
66
67 void
68 /*ARGSUSED*/
sethostent(int stayopen)69 sethostent(int stayopen)
70 {
71 res_static rs = __res_get_static();
72 if (rs) sethostent_r(&rs->hostf);
73 }
74
75 void
endhostent(void)76 endhostent(void)
77 {
78 res_static rs = __res_get_static();
79 if (rs) endhostent_r(&rs->hostf);
80 }
81
82 void
sethostent_r(FILE ** hf)83 sethostent_r(FILE **hf)
84 {
85 if (!*hf)
86 *hf = fopen(_PATH_HOSTS, "re");
87 else
88 rewind(*hf);
89 }
90
91 void
endhostent_r(FILE ** hf)92 endhostent_r(FILE **hf)
93 {
94 if (*hf) {
95 (void)fclose(*hf);
96 *hf = NULL;
97 }
98 }
99
100 /*ARGSUSED*/
101 int
_hf_gethtbyname(void * rv,void * cb_data,va_list ap)102 _hf_gethtbyname(void *rv, void *cb_data, va_list ap)
103 {
104 struct hostent *hp;
105 const char *name;
106 int af;
107 struct getnamaddr *info = rv;
108
109 _DIAGASSERT(rv != NULL);
110
111 name = va_arg(ap, char *);
112 /* NOSTRICT skip string len */(void)va_arg(ap, int);
113 af = va_arg(ap, int);
114
115 #if 0
116 {
117 res_state res = __res_get_state();
118 if (res == NULL)
119 return NS_NOTFOUND;
120 if (res->options & RES_USE_INET6)
121 hp = _hf_gethtbyname2(name, AF_INET6, info);
122 else
123 hp = NULL;
124 if (hp == NULL)
125 hp = _hf_gethtbyname2(name, AF_INET, info);
126 __res_put_state(res);
127 }
128 #else
129 hp = _hf_gethtbyname2(name, af, info);
130 #endif
131 if (hp == NULL) {
132 if (*info->he == NETDB_INTERNAL && errno == ENOSPC) {
133 return NS_UNAVAIL; // glibc compatibility.
134 }
135 *info->he = HOST_NOT_FOUND;
136 return NS_NOTFOUND;
137 }
138 return NS_SUCCESS;
139 }
140
141 struct hostent *
_hf_gethtbyname2(const char * name,int af,struct getnamaddr * info)142 _hf_gethtbyname2(const char *name, int af, struct getnamaddr *info)
143 {
144 struct hostent *hp, hent;
145 char *buf, *ptr;
146 size_t len, anum, num, i;
147 FILE *hf;
148 char *aliases[MAXALIASES];
149 char *addr_ptrs[MAXADDRS];
150
151 _DIAGASSERT(name != NULL);
152
153 hf = NULL;
154 sethostent_r(&hf);
155 if (hf == NULL) {
156 errno = EINVAL;
157 *info->he = NETDB_INTERNAL;
158 return NULL;
159 }
160
161 if ((ptr = buf = malloc(len = info->buflen)) == NULL) {
162 *info->he = NETDB_INTERNAL;
163 return NULL;
164 }
165
166 anum = 0; /* XXX: gcc */
167 hent.h_name = NULL; /* XXX: gcc */
168 hent.h_addrtype = 0; /* XXX: gcc */
169 hent.h_length = 0; /* XXX: gcc */
170
171 for (num = 0; num < MAXADDRS;) {
172 info->hp->h_addrtype = af;
173 info->hp->h_length = 0;
174
175 hp = netbsd_gethostent_r(hf, info->hp, info->buf, info->buflen,
176 info->he);
177 if (hp == NULL) {
178 if (*info->he == NETDB_INTERNAL && errno == ENOSPC) {
179 goto nospc; // glibc compatibility.
180 }
181 break;
182 }
183
184 if (strcasecmp(hp->h_name, name) != 0) {
185 char **cp;
186 for (cp = hp->h_aliases; *cp != NULL; cp++)
187 if (strcasecmp(*cp, name) == 0)
188 break;
189 if (*cp == NULL) continue;
190 }
191
192 if (num == 0) {
193 hent.h_addrtype = af = hp->h_addrtype;
194 hent.h_length = hp->h_length;
195
196 HENT_SCOPY(hent.h_name, hp->h_name, ptr, len);
197 for (anum = 0; hp->h_aliases[anum]; anum++) {
198 if (anum >= MAXALIASES)
199 goto nospc;
200 HENT_SCOPY(aliases[anum], hp->h_aliases[anum],
201 ptr, len);
202 }
203 ptr = (void *)ALIGN(ptr);
204 if ((size_t)(ptr - buf) >= info->buflen)
205 goto nospc;
206 }
207
208 if (num >= MAXADDRS)
209 goto nospc;
210 HENT_COPY(addr_ptrs[num], hp->h_addr_list[0], hp->h_length, ptr,
211 len);
212 num++;
213 }
214 endhostent_r(&hf);
215
216 if (num == 0) {
217 *info->he = HOST_NOT_FOUND;
218 free(buf);
219 return NULL;
220 }
221
222 hp = info->hp;
223 ptr = info->buf;
224 len = info->buflen;
225
226 hp->h_addrtype = hent.h_addrtype;
227 hp->h_length = hent.h_length;
228
229 HENT_ARRAY(hp->h_aliases, anum, ptr, len);
230 HENT_ARRAY(hp->h_addr_list, num, ptr, len);
231
232 for (i = 0; i < num; i++)
233 HENT_COPY(hp->h_addr_list[i], addr_ptrs[i], hp->h_length, ptr,
234 len);
235 hp->h_addr_list[num] = NULL;
236
237 HENT_SCOPY(hp->h_name, hent.h_name, ptr, len);
238
239 for (i = 0; i < anum; i++)
240 HENT_SCOPY(hp->h_aliases[i], aliases[i], ptr, len);
241 hp->h_aliases[anum] = NULL;
242
243 free(buf);
244 return hp;
245 nospc:
246 *info->he = NETDB_INTERNAL;
247 free(buf);
248 errno = ENOSPC;
249 return NULL;
250 }
251
252 /*ARGSUSED*/
253 int
_hf_gethtbyaddr(void * rv,void * cb_data,va_list ap)254 _hf_gethtbyaddr(void *rv, void *cb_data, va_list ap)
255 {
256 struct hostent *hp;
257 const unsigned char *addr;
258 struct getnamaddr *info = rv;
259 FILE *hf;
260
261 _DIAGASSERT(rv != NULL);
262
263 addr = va_arg(ap, unsigned char *);
264 info->hp->h_length = va_arg(ap, int);
265 info->hp->h_addrtype = va_arg(ap, int);
266
267 hf = NULL;
268 sethostent_r(&hf);
269 if (hf == NULL) {
270 *info->he = NETDB_INTERNAL;
271 return NS_UNAVAIL;
272 }
273 while ((hp = netbsd_gethostent_r(hf, info->hp, info->buf, info->buflen,
274 info->he)) != NULL)
275 if (!memcmp(hp->h_addr_list[0], addr, (size_t)hp->h_length))
276 break;
277 endhostent_r(&hf);
278
279 if (hp == NULL) {
280 if (errno == ENOSPC) return NS_UNAVAIL; // glibc compatibility.
281 *info->he = HOST_NOT_FOUND;
282 return NS_NOTFOUND;
283 }
284 return NS_SUCCESS;
285 }
286