xref: /dragonfly/lib/libc/net/gethostbyht.c (revision 99dd49c5)
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  * 4. 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  * @(#)gethostnamadr.c	8.1 (Berkeley) 6/4/93
50  * $FreeBSD: src/lib/libc/net/gethostbyht.c,v 1.27 2007/01/09 00:28:02 imp Exp $
51  * $DragonFly: src/lib/libc/net/gethostbyht.c,v 1.6 2005/11/13 02:04:47 swildner Exp $
52  */
53 
54 #include <sys/param.h>
55 #include <sys/socket.h>
56 #include <netinet/in.h>
57 #include <arpa/inet.h>
58 #include <netdb.h>
59 #include <stdio.h>
60 #include <ctype.h>
61 #include <string.h>
62 #include <stdarg.h>
63 #include <nsswitch.h>
64 #include <arpa/nameser.h>	/* XXX */
65 #include <resolv.h>		/* XXX */
66 #include "netdb_private.h"
67 
68 void
69 _sethosthtent(int f, struct hostent_data *hed)
70 {
71 	if (!hed->hostf)
72 		hed->hostf = fopen(_PATH_HOSTS, "r");
73 	else
74 		rewind(hed->hostf);
75 	hed->stayopen = f;
76 }
77 
78 void
79 _endhosthtent(struct hostent_data *hed)
80 {
81 	if (hed->hostf && !hed->stayopen) {
82 		fclose(hed->hostf);
83 		hed->hostf = NULL;
84 	}
85 }
86 
87 static int
88 gethostent_p(struct hostent *he, struct hostent_data *hed, int mapped,
89 	     res_state statp)
90 {
91 	char *p, *bp, *ep;
92 	char *cp, **q;
93 	int af, len;
94 	char hostbuf[BUFSIZ + 1];
95 
96 	if (!hed->hostf && !(hed->hostf = fopen(_PATH_HOSTS, "r"))) {
97 		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
98 		return (-1);
99 	}
100  again:
101 	if (!(p = fgets(hostbuf, sizeof hostbuf, hed->hostf))) {
102 		RES_SET_H_ERRNO(statp, HOST_NOT_FOUND);
103 		return (-1);
104 	}
105 	if (*p == '#')
106 		goto again;
107 	cp = strpbrk(p, "#\n");
108 	if (cp != NULL)
109 		*cp = '\0';
110 	if (!(cp = strpbrk(p, " \t")))
111 		goto again;
112 	*cp++ = '\0';
113 	if (inet_pton(AF_INET6, p, hed->host_addr) > 0) {
114 		af = AF_INET6;
115 		len = IN6ADDRSZ;
116 	} else if (inet_pton(AF_INET, p, hed->host_addr) > 0) {
117 		if (mapped) {
118 			_map_v4v6_address((char *)hed->host_addr,
119 			    (char *)hed->host_addr);
120 			af = AF_INET6;
121 			len = IN6ADDRSZ;
122 		} else {
123 			af = AF_INET;
124 			len = INADDRSZ;
125 		}
126 	} else {
127 		goto again;
128 	}
129 	hed->h_addr_ptrs[0] = (char *)hed->host_addr;
130 	hed->h_addr_ptrs[1] = NULL;
131 	he->h_addr_list = hed->h_addr_ptrs;
132 	he->h_length = len;
133 	he->h_addrtype = af;
134 	while (*cp == ' ' || *cp == '\t')
135 		cp++;
136 	bp = hed->hostbuf;
137 	ep = hed->hostbuf + sizeof hed->hostbuf;
138 	he->h_name = bp;
139 	q = he->h_aliases = hed->host_aliases;
140 	if ((p = strpbrk(cp, " \t")) != NULL)
141 		*p++ = '\0';
142 	len = strlen(cp) + 1;
143 	if (ep - bp < len) {
144 		RES_SET_H_ERRNO(statp, NO_RECOVERY);
145 		return (-1);
146 	}
147 	strlcpy(bp, cp, ep - bp);
148 	bp += len;
149 	cp = p;
150 	while (cp && *cp) {
151 		if (*cp == ' ' || *cp == '\t') {
152 			cp++;
153 			continue;
154 		}
155 		if (q >= &hed->host_aliases[_MAXALIASES - 1])
156 			break;
157 		if ((p = strpbrk(cp, " \t")) != NULL)
158 			*p++ = '\0';
159 		len = strlen(cp) + 1;
160 		if (ep - bp < len)
161 			break;
162 		strlcpy(bp, cp, ep - bp);
163 		*q++ = bp;
164 		bp += len;
165 		cp = p;
166 	}
167 	*q = NULL;
168 	RES_SET_H_ERRNO(statp, NETDB_SUCCESS);
169 	return (0);
170 }
171 
172 int
173 gethostent_r(struct hostent *hptr, char *buffer, size_t buflen,
174 	     struct hostent **result, int *h_errnop)
175 {
176 	struct hostent_data *hed;
177 	struct hostent he;
178 	res_state statp;
179 
180 	statp = __res_state();
181 	if ((statp->options & RES_INIT) == 0 && res_ninit(statp) == -1) {
182 		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
183 		*h_errnop = statp->res_h_errno;
184 		return (-1);
185 	}
186 	if ((hed = __hostent_data_init()) == NULL) {
187 		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
188 		*h_errnop = statp->res_h_errno;
189 		return (-1);
190 	}
191 	if (gethostent_p(&he, hed, statp->options & RES_USE_INET6, statp) != 0)
192 		return (-1);
193 	if (__copy_hostent(&he, hptr, buffer, buflen) != 0)
194 		return (-1);
195 	*result = hptr;
196 	return (0);
197 }
198 
199 struct hostent *
200 gethostent(void)
201 {
202 	struct hostdata *hd;
203 	struct hostent *rval;
204 	int ret_h_errno;
205 
206 	if ((hd = __hostdata_init()) == NULL)
207 		return (NULL);
208 	if (gethostent_r(&hd->host, hd->data, sizeof(hd->data), &rval,
209 	    &ret_h_errno) != 0)
210 		return (NULL);
211 	return (rval);
212 }
213 
214 int
215 _ht_gethostbyname(void *rval, void *cb_data, va_list ap)
216 {
217 	const char *name;
218 	int af;
219 	char *buffer;
220 	size_t buflen;
221 	int *errnop, *h_errnop;
222 	struct hostent *hptr, he;
223 	struct hostent_data *hed;
224 	char **cp;
225 	res_state statp;
226 	int error;
227 
228 	name = va_arg(ap, const char *);
229 	af = va_arg(ap, int);
230 	hptr = va_arg(ap, struct hostent *);
231 	buffer = va_arg(ap, char *);
232 	buflen = va_arg(ap, size_t);
233 	errnop = va_arg(ap, int *);
234 	h_errnop = va_arg(ap, int *);
235 
236 	*((struct hostent **)rval) = NULL;
237 
238 	statp = __res_state();
239 	if ((hed = __hostent_data_init()) == NULL) {
240 		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
241 		*h_errnop = statp->res_h_errno;
242 		return (NS_NOTFOUND);
243 	}
244 
245 	_sethosthtent(0, hed);
246 	while ((error = gethostent_p(&he, hed, 0, statp)) == 0) {
247 		if (he.h_addrtype != af)
248 			continue;
249 		if (he.h_addrtype == AF_INET &&
250 		    statp->options & RES_USE_INET6) {
251 			_map_v4v6_address(he.h_addr, he.h_addr);
252 			he.h_length = IN6ADDRSZ;
253 			he.h_addrtype = AF_INET6;
254 		}
255 		if (strcasecmp(he.h_name, name) == 0)
256 			break;
257 		for (cp = he.h_aliases; *cp != 0; cp++)
258 			if (strcasecmp(*cp, name) == 0)
259 				goto found;
260 	}
261 found:
262 	_endhosthtent(hed);
263 
264 	if (error != 0) {
265 		*h_errnop = statp->res_h_errno;
266 		return (NS_NOTFOUND);
267 	}
268 	if (__copy_hostent(&he, hptr, buffer, buflen) != 0) {
269 		*h_errnop = statp->res_h_errno;
270 		return (NS_NOTFOUND);
271 	}
272 	*((struct hostent **)rval) = hptr;
273 	return (NS_SUCCESS);
274 }
275 
276 int
277 _ht_gethostbyaddr(void *rval, void *cb_data, va_list ap)
278 {
279 	const void *addr;
280 	socklen_t len;
281 	int af;
282 	char *buffer;
283 	size_t buflen;
284 	int *errnop, *h_errnop;
285 	struct hostent *hptr, he;
286 	struct hostent_data *hed;
287 	res_state statp;
288 	int error;
289 
290 	addr = va_arg(ap, const void *);
291 	len = va_arg(ap, socklen_t);
292 	af = va_arg(ap, int);
293 	hptr = va_arg(ap, struct hostent *);
294 	buffer = va_arg(ap, char *);
295 	buflen = va_arg(ap, size_t);
296 	errnop = va_arg(ap, int *);
297 	h_errnop = va_arg(ap, int *);
298 
299 	*((struct hostent **)rval) = NULL;
300 
301 	statp = __res_state();
302 	if ((hed = __hostent_data_init()) == NULL) {
303 		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
304 		*h_errnop = statp->res_h_errno;
305 		return (NS_NOTFOUND);
306 	}
307 
308 	_sethosthtent(0, hed);
309 	while ((error = gethostent_p(&he, hed, 0, statp)) == 0)
310 		if (he.h_addrtype == af && !bcmp(he.h_addr, addr, len)) {
311 			if (he.h_addrtype == AF_INET &&
312 			    statp->options & RES_USE_INET6) {
313 				_map_v4v6_address(he.h_addr, he.h_addr);
314 				he.h_length = IN6ADDRSZ;
315 				he.h_addrtype = AF_INET6;
316 			}
317 			break;
318 		}
319 	_endhosthtent(hed);
320 
321 	if (error != 0)
322 		return (NS_NOTFOUND);
323 	if (__copy_hostent(&he, hptr, buffer, buflen) != 0) {
324 		*h_errnop = statp->res_h_errno;
325 		return (NS_NOTFOUND);
326 	}
327 	*((struct hostent **)rval) = hptr;
328 	return (NS_SUCCESS);
329 }
330