1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1985, 1988, 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 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
32 *
33 * Permission to use, copy, modify, and distribute this software for any
34 * purpose with or without fee is hereby granted, provided that the above
35 * copyright notice and this permission notice appear in all copies, and that
36 * the name of Digital Equipment Corporation not be used in advertising or
37 * publicity pertaining to distribution of the document or software without
38 * specific, written prior permission.
39 *
40 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
41 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
42 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
43 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
44 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
45 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
46 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
47 * SOFTWARE.
48 * -
49 * --Copyright--
50 */
51
52 #include <sys/param.h>
53 #include <sys/socket.h>
54 #include <netinet/in.h>
55 #include <arpa/inet.h>
56 #include <netdb.h>
57 #include <stdio.h>
58 #include <ctype.h>
59 #include <errno.h>
60 #include <string.h>
61 #include <stdarg.h>
62 #include <nsswitch.h>
63 #include <arpa/nameser.h> /* XXX */
64 #include <resolv.h> /* XXX */
65 #include "netdb_private.h"
66
67 void
_sethosthtent(int f,struct hostent_data * hed)68 _sethosthtent(int f, struct hostent_data *hed)
69 {
70 if (!hed->hostf)
71 hed->hostf = fopen(_PATH_HOSTS, "re");
72 else
73 rewind(hed->hostf);
74 hed->stayopen = f;
75 }
76
77 void
_endhosthtent(struct hostent_data * hed)78 _endhosthtent(struct hostent_data *hed)
79 {
80 if (hed->hostf && !hed->stayopen) {
81 (void) fclose(hed->hostf);
82 hed->hostf = NULL;
83 }
84 }
85
86 static int
gethostent_p(struct hostent * he,struct hostent_data * hed,int mapped,res_state statp)87 gethostent_p(struct hostent *he, struct hostent_data *hed, int mapped,
88 res_state statp)
89 {
90 char *p, *bp, *ep;
91 char *cp, **q;
92 int af, len;
93 char hostbuf[BUFSIZ + 1];
94
95 if (!hed->hostf && !(hed->hostf = fopen(_PATH_HOSTS, "re"))) {
96 RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
97 return (-1);
98 }
99 again:
100 if (!(p = fgets(hostbuf, sizeof hostbuf, hed->hostf))) {
101 RES_SET_H_ERRNO(statp, HOST_NOT_FOUND);
102 return (-1);
103 }
104 if (*p == '#')
105 goto again;
106 cp = strpbrk(p, "#\n");
107 if (cp != NULL)
108 *cp = '\0';
109 if (!(cp = strpbrk(p, " \t")))
110 goto again;
111 *cp++ = '\0';
112 if (inet_pton(AF_INET6, p, hed->host_addr) > 0) {
113 af = AF_INET6;
114 len = IN6ADDRSZ;
115 } else if (inet_pton(AF_INET, p, hed->host_addr) > 0) {
116 if (mapped) {
117 _map_v4v6_address((char *)hed->host_addr,
118 (char *)hed->host_addr);
119 af = AF_INET6;
120 len = IN6ADDRSZ;
121 } else {
122 af = AF_INET;
123 len = INADDRSZ;
124 }
125 } else {
126 goto again;
127 }
128 hed->h_addr_ptrs[0] = (char *)hed->host_addr;
129 hed->h_addr_ptrs[1] = NULL;
130 he->h_addr_list = hed->h_addr_ptrs;
131 he->h_length = len;
132 he->h_addrtype = af;
133 while (*cp == ' ' || *cp == '\t')
134 cp++;
135 bp = hed->hostbuf;
136 ep = hed->hostbuf + sizeof hed->hostbuf;
137 he->h_name = bp;
138 q = he->h_aliases = hed->host_aliases;
139 if ((p = strpbrk(cp, " \t")) != NULL)
140 *p++ = '\0';
141 len = strlen(cp) + 1;
142 if (ep - bp < len) {
143 RES_SET_H_ERRNO(statp, NO_RECOVERY);
144 return (-1);
145 }
146 strlcpy(bp, cp, ep - bp);
147 bp += len;
148 cp = p;
149 while (cp && *cp) {
150 if (*cp == ' ' || *cp == '\t') {
151 cp++;
152 continue;
153 }
154 if (q >= &hed->host_aliases[_MAXALIASES - 1])
155 break;
156 if ((p = strpbrk(cp, " \t")) != NULL)
157 *p++ = '\0';
158 len = strlen(cp) + 1;
159 if (ep - bp < len)
160 break;
161 strlcpy(bp, cp, ep - bp);
162 *q++ = bp;
163 bp += len;
164 cp = p;
165 }
166 *q = NULL;
167 RES_SET_H_ERRNO(statp, NETDB_SUCCESS);
168 return (0);
169 }
170
171 int
gethostent_r(struct hostent * hptr,char * buffer,size_t buflen,struct hostent ** result,int * h_errnop)172 gethostent_r(struct hostent *hptr, char *buffer, size_t buflen,
173 struct hostent **result, int *h_errnop)
174 {
175 struct hostent_data *hed;
176 struct hostent he;
177 res_state statp;
178
179 statp = __res_state();
180 if ((statp->options & RES_INIT) == 0 && res_ninit(statp) == -1) {
181 RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
182 *h_errnop = statp->res_h_errno;
183 return (-1);
184 }
185 if ((hed = __hostent_data_init()) == NULL) {
186 RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
187 *h_errnop = statp->res_h_errno;
188 return (-1);
189 }
190 if (gethostent_p(&he, hed, statp->options & RES_USE_INET6, statp) != 0)
191 return (-1);
192 if (__copy_hostent(&he, hptr, buffer, buflen) != 0) {
193 RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
194 *h_errnop = statp->res_h_errno;
195 return ((errno != 0) ? errno : -1);
196 }
197 *result = hptr;
198 return (0);
199 }
200
201 struct hostent *
gethostent(void)202 gethostent(void)
203 {
204 struct hostdata *hd;
205 struct hostent *rval;
206 int ret_h_errno;
207
208 if ((hd = __hostdata_init()) == NULL)
209 return (NULL);
210 if (gethostent_r(&hd->host, hd->data, sizeof(hd->data), &rval,
211 &ret_h_errno) != 0)
212 return (NULL);
213 return (rval);
214 }
215
216 int
_ht_gethostbyname(void * rval,void * cb_data,va_list ap)217 _ht_gethostbyname(void *rval, void *cb_data, va_list ap)
218 {
219 const char *name;
220 int af;
221 char *buffer;
222 size_t buflen;
223 int *errnop, *h_errnop;
224 struct hostent *hptr, he;
225 struct hostent_data *hed;
226 char **cp;
227 res_state statp;
228 int error;
229
230 name = va_arg(ap, const char *);
231 af = va_arg(ap, int);
232 hptr = va_arg(ap, struct hostent *);
233 buffer = va_arg(ap, char *);
234 buflen = va_arg(ap, size_t);
235 errnop = va_arg(ap, int *);
236 h_errnop = va_arg(ap, int *);
237
238 *((struct hostent **)rval) = NULL;
239
240 statp = __res_state();
241 if ((hed = __hostent_data_init()) == NULL) {
242 RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
243 *h_errnop = statp->res_h_errno;
244 return (NS_NOTFOUND);
245 }
246
247 _sethosthtent(0, hed);
248 while ((error = gethostent_p(&he, hed, 0, statp)) == 0) {
249 if (he.h_addrtype != af)
250 continue;
251 if (he.h_addrtype == AF_INET &&
252 statp->options & RES_USE_INET6) {
253 _map_v4v6_address(he.h_addr, he.h_addr);
254 he.h_length = IN6ADDRSZ;
255 he.h_addrtype = AF_INET6;
256 }
257 if (strcasecmp(he.h_name, name) == 0)
258 break;
259 for (cp = he.h_aliases; *cp != 0; cp++)
260 if (strcasecmp(*cp, name) == 0)
261 goto found;
262 }
263 found:
264 _endhosthtent(hed);
265
266 if (error != 0) {
267 *h_errnop = statp->res_h_errno;
268 return (NS_NOTFOUND);
269 }
270 if (__copy_hostent(&he, hptr, buffer, buflen) != 0) {
271 *errnop = errno;
272 RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
273 *h_errnop = statp->res_h_errno;
274 return (NS_RETURN);
275 }
276 *((struct hostent **)rval) = hptr;
277 return (NS_SUCCESS);
278 }
279
280 int
_ht_gethostbyaddr(void * rval,void * cb_data,va_list ap)281 _ht_gethostbyaddr(void *rval, void *cb_data, va_list ap)
282 {
283 const void *addr;
284 socklen_t len;
285 int af;
286 char *buffer;
287 size_t buflen;
288 int *errnop, *h_errnop;
289 struct hostent *hptr, he;
290 struct hostent_data *hed;
291 res_state statp;
292 int error;
293
294 addr = va_arg(ap, const void *);
295 len = va_arg(ap, socklen_t);
296 af = va_arg(ap, int);
297 hptr = va_arg(ap, struct hostent *);
298 buffer = va_arg(ap, char *);
299 buflen = va_arg(ap, size_t);
300 errnop = va_arg(ap, int *);
301 h_errnop = va_arg(ap, int *);
302
303 *((struct hostent **)rval) = NULL;
304
305 statp = __res_state();
306 if ((hed = __hostent_data_init()) == NULL) {
307 RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
308 *h_errnop = statp->res_h_errno;
309 return (NS_NOTFOUND);
310 }
311
312 _sethosthtent(0, hed);
313 while ((error = gethostent_p(&he, hed, 0, statp)) == 0)
314 if (he.h_addrtype == af && !bcmp(he.h_addr, addr, len)) {
315 if (he.h_addrtype == AF_INET &&
316 statp->options & RES_USE_INET6) {
317 _map_v4v6_address(he.h_addr, he.h_addr);
318 he.h_length = IN6ADDRSZ;
319 he.h_addrtype = AF_INET6;
320 }
321 break;
322 }
323 _endhosthtent(hed);
324
325 if (error != 0)
326 return (NS_NOTFOUND);
327 if (__copy_hostent(&he, hptr, buffer, buflen) != 0) {
328 *errnop = errno;
329 RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
330 *h_errnop = statp->res_h_errno;
331 return (NS_RETURN);
332 }
333 *((struct hostent **)rval) = hptr;
334 return (NS_SUCCESS);
335 }
336