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
67void
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
77void
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
86static int
87gethostent_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
171int
172gethostent_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
201struct hostent *
202gethostent(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
216int
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	}
263found:
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
280int
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