xref: /freebsd/lib/libc/net/gethostbyht.c (revision 3da59cd0072b20be9464c3f0afe83579fc83909c)
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. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  * -
33  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
34  *
35  * Permission to use, copy, modify, and distribute this software for any
36  * purpose with or without fee is hereby granted, provided that the above
37  * copyright notice and this permission notice appear in all copies, and that
38  * the name of Digital Equipment Corporation not be used in advertising or
39  * publicity pertaining to distribution of the document or software without
40  * specific, written prior permission.
41  *
42  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
43  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
44  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
45  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
46  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
47  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
48  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
49  * SOFTWARE.
50  * -
51  * --Copyright--
52  */
53 
54 #if defined(LIBC_SCCS) && !defined(lint)
55 static char sccsid[] = "@(#)gethostnamadr.c	8.1 (Berkeley) 6/4/93";
56 #endif /* LIBC_SCCS and not lint */
57 #include <sys/cdefs.h>
58 __FBSDID("$FreeBSD$");
59 
60 #include <sys/param.h>
61 #include <sys/socket.h>
62 #include <netinet/in.h>
63 #include <arpa/inet.h>
64 #include <netdb.h>
65 #include <stdio.h>
66 #include <ctype.h>
67 #include <string.h>
68 #include <stdarg.h>
69 #include <nsswitch.h>
70 #include <arpa/nameser.h>	/* XXX */
71 #include <resolv.h>		/* XXX */
72 #include "netdb_private.h"
73 
74 void
75 _sethosthtent(int f, struct hostent_data *hed)
76 {
77 	if (!hed->hostf)
78 		hed->hostf = fopen(_PATH_HOSTS, "r");
79 	else
80 		rewind(hed->hostf);
81 	hed->stayopen = f;
82 }
83 
84 void
85 _endhosthtent(struct hostent_data *hed)
86 {
87 	if (hed->hostf && !hed->stayopen) {
88 		(void) fclose(hed->hostf);
89 		hed->hostf = NULL;
90 	}
91 }
92 
93 static int
94 gethostent_p(struct hostent *he, struct hostent_data *hed, int mapped,
95     res_state statp)
96 {
97 	char *p, *bp, *ep;
98 	char *cp, **q;
99 	int af, len;
100 	char hostbuf[BUFSIZ + 1];
101 
102 	if (!hed->hostf && !(hed->hostf = fopen(_PATH_HOSTS, "r"))) {
103 		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
104 		return (-1);
105 	}
106  again:
107 	if (!(p = fgets(hostbuf, sizeof hostbuf, hed->hostf))) {
108 		RES_SET_H_ERRNO(statp, HOST_NOT_FOUND);
109 		return (-1);
110 	}
111 	if (*p == '#')
112 		goto again;
113 	cp = strpbrk(p, "#\n");
114 	if (cp != NULL)
115 		*cp = '\0';
116 	if (!(cp = strpbrk(p, " \t")))
117 		goto again;
118 	*cp++ = '\0';
119 	if (inet_pton(AF_INET6, p, hed->host_addr) > 0) {
120 		af = AF_INET6;
121 		len = IN6ADDRSZ;
122 	} else if (inet_pton(AF_INET, p, hed->host_addr) > 0) {
123 		if (mapped) {
124 			_map_v4v6_address((char *)hed->host_addr,
125 			    (char *)hed->host_addr);
126 			af = AF_INET6;
127 			len = IN6ADDRSZ;
128 		} else {
129 			af = AF_INET;
130 			len = INADDRSZ;
131 		}
132 	} else {
133 		goto again;
134 	}
135 	hed->h_addr_ptrs[0] = (char *)hed->host_addr;
136 	hed->h_addr_ptrs[1] = NULL;
137 	he->h_addr_list = hed->h_addr_ptrs;
138 	he->h_length = len;
139 	he->h_addrtype = af;
140 	while (*cp == ' ' || *cp == '\t')
141 		cp++;
142 	bp = hed->hostbuf;
143 	ep = hed->hostbuf + sizeof hed->hostbuf;
144 	he->h_name = bp;
145 	q = he->h_aliases = hed->host_aliases;
146 	if ((p = strpbrk(cp, " \t")) != NULL)
147 		*p++ = '\0';
148 	len = strlen(cp) + 1;
149 	if (ep - bp < len) {
150 		RES_SET_H_ERRNO(statp, NO_RECOVERY);
151 		return (-1);
152 	}
153 	strlcpy(bp, cp, ep - bp);
154 	bp += len;
155 	cp = p;
156 	while (cp && *cp) {
157 		if (*cp == ' ' || *cp == '\t') {
158 			cp++;
159 			continue;
160 		}
161 		if (q >= &hed->host_aliases[_MAXALIASES - 1])
162 			break;
163 		if ((p = strpbrk(cp, " \t")) != NULL)
164 			*p++ = '\0';
165 		len = strlen(cp) + 1;
166 		if (ep - bp < len)
167 			break;
168 		strlcpy(bp, cp, ep - bp);
169 		*q++ = bp;
170 		bp += len;
171 		cp = p;
172 	}
173 	*q = NULL;
174 	RES_SET_H_ERRNO(statp, NETDB_SUCCESS);
175 	return (0);
176 }
177 
178 int
179 gethostent_r(struct hostent *hptr, char *buffer, size_t buflen,
180     struct hostent **result, int *h_errnop)
181 {
182 	struct hostent_data *hed;
183 	struct hostent he;
184 	res_state statp;
185 
186 	statp = __res_state();
187 	if ((statp->options & RES_INIT) == 0 && res_ninit(statp) == -1) {
188 		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
189 		*h_errnop = statp->res_h_errno;
190 		return (-1);
191 	}
192 	if ((hed = __hostent_data_init()) == NULL) {
193 		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
194 		*h_errnop = statp->res_h_errno;
195 		return (-1);
196 	}
197 	if (gethostent_p(&he, hed, statp->options & RES_USE_INET6, statp) != 0)
198 		return (-1);
199 	if (__copy_hostent(&he, hptr, buffer, buflen) != 0)
200 		return (-1);
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 		*h_errnop = statp->res_h_errno;
276 		return (NS_NOTFOUND);
277 	}
278 	*((struct hostent **)rval) = hptr;
279 	return (NS_SUCCESS);
280 }
281 
282 int
283 _ht_gethostbyaddr(void *rval, void *cb_data, va_list ap)
284 {
285 	const void *addr;
286 	socklen_t len;
287 	int af;
288 	char *buffer;
289 	size_t buflen;
290 	int *errnop, *h_errnop;
291 	struct hostent *hptr, he;
292 	struct hostent_data *hed;
293 	res_state statp;
294 	int error;
295 
296 	addr = va_arg(ap, const void *);
297 	len = va_arg(ap, socklen_t);
298 	af = va_arg(ap, int);
299 	hptr = va_arg(ap, struct hostent *);
300 	buffer = va_arg(ap, char *);
301 	buflen = va_arg(ap, size_t);
302 	errnop = va_arg(ap, int *);
303 	h_errnop = va_arg(ap, int *);
304 
305 	*((struct hostent **)rval) = NULL;
306 
307 	statp = __res_state();
308 	if ((hed = __hostent_data_init()) == NULL) {
309 		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
310 		*h_errnop = statp->res_h_errno;
311 		return (NS_NOTFOUND);
312 	}
313 
314 	_sethosthtent(0, hed);
315 	while ((error = gethostent_p(&he, hed, 0, statp)) == 0)
316 		if (he.h_addrtype == af && !bcmp(he.h_addr, addr, len)) {
317 			if (he.h_addrtype == AF_INET &&
318 			    statp->options & RES_USE_INET6) {
319 				_map_v4v6_address(he.h_addr, he.h_addr);
320 				he.h_length = IN6ADDRSZ;
321 				he.h_addrtype = AF_INET6;
322 			}
323 			break;
324 		}
325 	_endhosthtent(hed);
326 
327 	if (error != 0)
328 		return (NS_NOTFOUND);
329 	if (__copy_hostent(&he, hptr, buffer, buflen) != 0) {
330 		*h_errnop = statp->res_h_errno;
331 		return (NS_NOTFOUND);
332 	}
333 	*((struct hostent **)rval) = hptr;
334 	return (NS_SUCCESS);
335 }
336