xref: /freebsd/lib/libc/net/gethostbyht.c (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
1 /*-
2  * Copyright (c) 1985, 1988, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  * -
29  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
30  *
31  * Permission to use, copy, modify, and distribute this software for any
32  * purpose with or without fee is hereby granted, provided that the above
33  * copyright notice and this permission notice appear in all copies, and that
34  * the name of Digital Equipment Corporation not be used in advertising or
35  * publicity pertaining to distribution of the document or software without
36  * specific, written prior permission.
37  *
38  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
39  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
40  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
41  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
42  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
43  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
44  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
45  * SOFTWARE.
46  * -
47  * --Copyright--
48  */
49 
50 #if defined(LIBC_SCCS) && !defined(lint)
51 static char sccsid[] = "@(#)gethostnamadr.c	8.1 (Berkeley) 6/4/93";
52 #endif /* LIBC_SCCS and not lint */
53 #include <sys/cdefs.h>
54 __FBSDID("$FreeBSD$");
55 
56 #include <sys/param.h>
57 #include <sys/socket.h>
58 #include <netinet/in.h>
59 #include <arpa/inet.h>
60 #include <netdb.h>
61 #include <stdio.h>
62 #include <ctype.h>
63 #include <errno.h>
64 #include <string.h>
65 #include <stdarg.h>
66 #include <nsswitch.h>
67 #include <arpa/nameser.h>	/* XXX */
68 #include <resolv.h>		/* XXX */
69 #include "netdb_private.h"
70 
71 void
72 _sethosthtent(int f, struct hostent_data *hed)
73 {
74 	if (!hed->hostf)
75 		hed->hostf = fopen(_PATH_HOSTS, "re");
76 	else
77 		rewind(hed->hostf);
78 	hed->stayopen = f;
79 }
80 
81 void
82 _endhosthtent(struct hostent_data *hed)
83 {
84 	if (hed->hostf && !hed->stayopen) {
85 		(void) fclose(hed->hostf);
86 		hed->hostf = NULL;
87 	}
88 }
89 
90 static int
91 gethostent_p(struct hostent *he, struct hostent_data *hed, int mapped,
92     res_state statp)
93 {
94 	char *p, *bp, *ep;
95 	char *cp, **q;
96 	int af, len;
97 	char hostbuf[BUFSIZ + 1];
98 
99 	if (!hed->hostf && !(hed->hostf = fopen(_PATH_HOSTS, "re"))) {
100 		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
101 		return (-1);
102 	}
103  again:
104 	if (!(p = fgets(hostbuf, sizeof hostbuf, hed->hostf))) {
105 		RES_SET_H_ERRNO(statp, HOST_NOT_FOUND);
106 		return (-1);
107 	}
108 	if (*p == '#')
109 		goto again;
110 	cp = strpbrk(p, "#\n");
111 	if (cp != NULL)
112 		*cp = '\0';
113 	if (!(cp = strpbrk(p, " \t")))
114 		goto again;
115 	*cp++ = '\0';
116 	if (inet_pton(AF_INET6, p, hed->host_addr) > 0) {
117 		af = AF_INET6;
118 		len = IN6ADDRSZ;
119 	} else if (inet_pton(AF_INET, p, hed->host_addr) > 0) {
120 		if (mapped) {
121 			_map_v4v6_address((char *)hed->host_addr,
122 			    (char *)hed->host_addr);
123 			af = AF_INET6;
124 			len = IN6ADDRSZ;
125 		} else {
126 			af = AF_INET;
127 			len = INADDRSZ;
128 		}
129 	} else {
130 		goto again;
131 	}
132 	hed->h_addr_ptrs[0] = (char *)hed->host_addr;
133 	hed->h_addr_ptrs[1] = NULL;
134 	he->h_addr_list = hed->h_addr_ptrs;
135 	he->h_length = len;
136 	he->h_addrtype = af;
137 	while (*cp == ' ' || *cp == '\t')
138 		cp++;
139 	bp = hed->hostbuf;
140 	ep = hed->hostbuf + sizeof hed->hostbuf;
141 	he->h_name = bp;
142 	q = he->h_aliases = hed->host_aliases;
143 	if ((p = strpbrk(cp, " \t")) != NULL)
144 		*p++ = '\0';
145 	len = strlen(cp) + 1;
146 	if (ep - bp < len) {
147 		RES_SET_H_ERRNO(statp, NO_RECOVERY);
148 		return (-1);
149 	}
150 	strlcpy(bp, cp, ep - bp);
151 	bp += len;
152 	cp = p;
153 	while (cp && *cp) {
154 		if (*cp == ' ' || *cp == '\t') {
155 			cp++;
156 			continue;
157 		}
158 		if (q >= &hed->host_aliases[_MAXALIASES - 1])
159 			break;
160 		if ((p = strpbrk(cp, " \t")) != NULL)
161 			*p++ = '\0';
162 		len = strlen(cp) + 1;
163 		if (ep - bp < len)
164 			break;
165 		strlcpy(bp, cp, ep - bp);
166 		*q++ = bp;
167 		bp += len;
168 		cp = p;
169 	}
170 	*q = NULL;
171 	RES_SET_H_ERRNO(statp, NETDB_SUCCESS);
172 	return (0);
173 }
174 
175 int
176 gethostent_r(struct hostent *hptr, char *buffer, size_t buflen,
177     struct hostent **result, int *h_errnop)
178 {
179 	struct hostent_data *hed;
180 	struct hostent he;
181 	res_state statp;
182 
183 	statp = __res_state();
184 	if ((statp->options & RES_INIT) == 0 && res_ninit(statp) == -1) {
185 		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
186 		*h_errnop = statp->res_h_errno;
187 		return (-1);
188 	}
189 	if ((hed = __hostent_data_init()) == NULL) {
190 		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
191 		*h_errnop = statp->res_h_errno;
192 		return (-1);
193 	}
194 	if (gethostent_p(&he, hed, statp->options & RES_USE_INET6, statp) != 0)
195 		return (-1);
196 	if (__copy_hostent(&he, hptr, buffer, buflen) != 0) {
197 		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
198 		*h_errnop = statp->res_h_errno;
199 		return ((errno != 0) ? errno : -1);
200 	}
201 	*result = hptr;
202 	return (0);
203 }
204 
205 struct hostent *
206 gethostent(void)
207 {
208 	struct hostdata *hd;
209 	struct hostent *rval;
210 	int ret_h_errno;
211 
212 	if ((hd = __hostdata_init()) == NULL)
213 		return (NULL);
214 	if (gethostent_r(&hd->host, hd->data, sizeof(hd->data), &rval,
215 	    &ret_h_errno) != 0)
216 		return (NULL);
217 	return (rval);
218 }
219 
220 int
221 _ht_gethostbyname(void *rval, void *cb_data, va_list ap)
222 {
223 	const char *name;
224 	int af;
225 	char *buffer;
226 	size_t buflen;
227 	int *errnop, *h_errnop;
228 	struct hostent *hptr, he;
229 	struct hostent_data *hed;
230 	char **cp;
231 	res_state statp;
232 	int error;
233 
234 	name = va_arg(ap, const char *);
235 	af = va_arg(ap, int);
236 	hptr = va_arg(ap, struct hostent *);
237 	buffer = va_arg(ap, char *);
238 	buflen = va_arg(ap, size_t);
239 	errnop = va_arg(ap, int *);
240 	h_errnop = va_arg(ap, int *);
241 
242 	*((struct hostent **)rval) = NULL;
243 
244 	statp = __res_state();
245 	if ((hed = __hostent_data_init()) == NULL) {
246 		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
247 		*h_errnop = statp->res_h_errno;
248 		return (NS_NOTFOUND);
249 	}
250 
251 	_sethosthtent(0, hed);
252 	while ((error = gethostent_p(&he, hed, 0, statp)) == 0) {
253 		if (he.h_addrtype != af)
254 			continue;
255 		if (he.h_addrtype == AF_INET &&
256 		    statp->options & RES_USE_INET6) {
257 			_map_v4v6_address(he.h_addr, he.h_addr);
258 			he.h_length = IN6ADDRSZ;
259 			he.h_addrtype = AF_INET6;
260 		}
261 		if (strcasecmp(he.h_name, name) == 0)
262 			break;
263 		for (cp = he.h_aliases; *cp != 0; cp++)
264 			if (strcasecmp(*cp, name) == 0)
265 				goto found;
266 	}
267 found:
268 	_endhosthtent(hed);
269 
270 	if (error != 0) {
271 		*h_errnop = statp->res_h_errno;
272 		return (NS_NOTFOUND);
273 	}
274 	if (__copy_hostent(&he, hptr, buffer, buflen) != 0) {
275 		*errnop = errno;
276 		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
277 		*h_errnop = statp->res_h_errno;
278 		return (NS_RETURN);
279 	}
280 	*((struct hostent **)rval) = hptr;
281 	return (NS_SUCCESS);
282 }
283 
284 int
285 _ht_gethostbyaddr(void *rval, void *cb_data, va_list ap)
286 {
287 	const void *addr;
288 	socklen_t len;
289 	int af;
290 	char *buffer;
291 	size_t buflen;
292 	int *errnop, *h_errnop;
293 	struct hostent *hptr, he;
294 	struct hostent_data *hed;
295 	res_state statp;
296 	int error;
297 
298 	addr = va_arg(ap, const void *);
299 	len = va_arg(ap, socklen_t);
300 	af = va_arg(ap, int);
301 	hptr = va_arg(ap, struct hostent *);
302 	buffer = va_arg(ap, char *);
303 	buflen = va_arg(ap, size_t);
304 	errnop = va_arg(ap, int *);
305 	h_errnop = va_arg(ap, int *);
306 
307 	*((struct hostent **)rval) = NULL;
308 
309 	statp = __res_state();
310 	if ((hed = __hostent_data_init()) == NULL) {
311 		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
312 		*h_errnop = statp->res_h_errno;
313 		return (NS_NOTFOUND);
314 	}
315 
316 	_sethosthtent(0, hed);
317 	while ((error = gethostent_p(&he, hed, 0, statp)) == 0)
318 		if (he.h_addrtype == af && !bcmp(he.h_addr, addr, len)) {
319 			if (he.h_addrtype == AF_INET &&
320 			    statp->options & RES_USE_INET6) {
321 				_map_v4v6_address(he.h_addr, he.h_addr);
322 				he.h_length = IN6ADDRSZ;
323 				he.h_addrtype = AF_INET6;
324 			}
325 			break;
326 		}
327 	_endhosthtent(hed);
328 
329 	if (error != 0)
330 		return (NS_NOTFOUND);
331 	if (__copy_hostent(&he, hptr, buffer, buflen) != 0) {
332 		*errnop = errno;
333 		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
334 		*h_errnop = statp->res_h_errno;
335 		return (NS_RETURN);
336 	}
337 	*((struct hostent **)rval) = hptr;
338 	return (NS_SUCCESS);
339 }
340