1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 1994, Garrett Wollman
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28#include <sys/cdefs.h>
29__FBSDID("$FreeBSD$");
30
31#include <sys/param.h>
32#include <sys/socket.h>
33#include <netinet/in.h>
34#include <arpa/inet.h>
35#include <arpa/nameser.h>
36#include <netdb.h>
37#include <stdio.h>
38#include <stdlib.h>
39#include <ctype.h>
40#include <errno.h>
41#include <string.h>
42#include <stdarg.h>
43#include <nsswitch.h>
44#include <resolv.h>		/* XXX */
45#ifdef YP
46#include <rpc/rpc.h>
47#include <rpcsvc/yp_prot.h>
48#include <rpcsvc/ypclnt.h>
49#endif
50#include "netdb_private.h"
51
52#ifdef YP
53static int
54_gethostbynis(const char *name, char *map, int af, struct hostent *he,
55    struct hostent_data *hed)
56{
57	char *p, *bp, *ep;
58	char *cp, **q;
59	char *result;
60	int resultlen, size, addrok = 0;
61	char *ypbuf;
62	res_state statp;
63
64	statp = __res_state();
65	switch(af) {
66	case AF_INET:
67		size = NS_INADDRSZ;
68		break;
69	case AF_INET6:
70		size = NS_IN6ADDRSZ;
71		break;
72	default:
73		errno = EAFNOSUPPORT;
74		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
75		return (-1);
76	}
77
78	if (hed->yp_domain == (char *)NULL)
79		if (yp_get_default_domain (&hed->yp_domain)) {
80			RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
81			return (-1);
82		}
83
84	if (yp_match(hed->yp_domain, map, name, strlen(name), &result,
85	    &resultlen)) {
86		RES_SET_H_ERRNO(statp, HOST_NOT_FOUND);
87		return (-1);
88	}
89
90	/* avoid potential memory leak */
91	ypbuf = alloca(resultlen + 2);
92	bcopy(result, ypbuf, resultlen);
93	ypbuf[resultlen] = '\0';
94	free(result);
95	result = ypbuf;
96
97	if ((cp = strchr(result, '\n')))
98		*cp = '\0';
99
100	cp = strpbrk(result, " \t");
101	*cp++ = '\0';
102	he->h_addr_list = hed->h_addr_ptrs;
103	he->h_addr = (char *)hed->host_addr;
104	switch (af) {
105	case AF_INET:
106		addrok = inet_aton(result, (struct in_addr *)hed->host_addr);
107		if (addrok != 1)
108			break;
109		if (statp->options & RES_USE_INET6) {
110			_map_v4v6_address((char *)hed->host_addr,
111			    (char *)hed->host_addr);
112			af = AF_INET6;
113			size = NS_IN6ADDRSZ;
114		}
115		break;
116	case AF_INET6:
117		addrok = inet_pton(af, result, hed->host_addr);
118		break;
119	}
120	if (addrok != 1) {
121		RES_SET_H_ERRNO(statp, HOST_NOT_FOUND);
122		return (-1);
123	}
124	he->h_addr_list[1] = NULL;
125	he->h_length = size;
126	he->h_addrtype = af;
127	while (*cp == ' ' || *cp == '\t')
128		cp++;
129	bp = hed->hostbuf;
130	ep = hed->hostbuf + sizeof hed->hostbuf;
131	he->h_name = bp;
132	q = he->h_aliases = hed->host_aliases;
133	p = strpbrk(cp, " \t");
134	if (p != NULL)
135		*p++ = '\0';
136	size = strlen(cp) + 1;
137	if (ep - bp < size) {
138		RES_SET_H_ERRNO(statp, NO_RECOVERY);
139		return (-1);
140	}
141	strlcpy(bp, cp, ep - bp);
142	bp += size;
143	cp = p;
144	while (cp && *cp) {
145		if (*cp == ' ' || *cp == '\t') {
146			cp++;
147			continue;
148		}
149		if (q >= &hed->host_aliases[_MAXALIASES - 1])
150			break;
151		p = strpbrk(cp, " \t");
152		if (p != NULL)
153			*p++ = '\0';
154		size = strlen(cp) + 1;
155		if (ep - bp < size)
156			break;
157		strlcpy(bp, cp, ep - bp);
158		*q++ = bp;
159		bp += size;
160		cp = p;
161	}
162	*q = NULL;
163	return (0);
164}
165
166static int
167_gethostbynisname_r(const char *name, int af, struct hostent *he,
168    struct hostent_data *hed)
169{
170	char *map;
171
172	switch (af) {
173	case AF_INET:
174		map = "hosts.byname";
175		break;
176	default:
177		map = "ipnodes.byname";
178		break;
179	}
180	return (_gethostbynis(name, map, af, he, hed));
181}
182
183static int
184_gethostbynisaddr_r(const void *addr, socklen_t len, int af,
185    struct hostent *he, struct hostent_data *hed)
186{
187	char *map;
188	char numaddr[46];
189
190	switch (af) {
191	case AF_INET:
192		map = "hosts.byaddr";
193		break;
194	default:
195		map = "ipnodes.byaddr";
196		break;
197	}
198	if (inet_ntop(af, addr, numaddr, sizeof(numaddr)) == NULL)
199		return (-1);
200	return (_gethostbynis(numaddr, map, af, he, hed));
201}
202#endif /* YP */
203
204int
205_nis_gethostbyname(void *rval, void *cb_data, va_list ap)
206{
207#ifdef YP
208	const char *name;
209	int af;
210	char *buffer;
211	size_t buflen;
212	int *errnop, *h_errnop;
213	struct hostent *hptr, he;
214	struct hostent_data *hed;
215	res_state statp;
216
217	name = va_arg(ap, const char *);
218	af = va_arg(ap, int);
219	hptr = va_arg(ap, struct hostent *);
220	buffer = va_arg(ap, char *);
221	buflen = va_arg(ap, size_t);
222	errnop = va_arg(ap, int *);
223	h_errnop = va_arg(ap, int *);
224
225	*((struct hostent **)rval) = NULL;
226
227	statp = __res_state();
228	if ((hed = __hostent_data_init()) == NULL) {
229		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
230		*h_errnop = statp->res_h_errno;
231		return (NS_NOTFOUND);
232	}
233
234	if (_gethostbynisname_r(name, af, &he, hed) != 0) {
235		*h_errnop = statp->res_h_errno;
236		return (NS_NOTFOUND);
237	}
238	if (__copy_hostent(&he, hptr, buffer, buflen) != 0) {
239		*errnop = errno;
240		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
241		*h_errnop = statp->res_h_errno;
242		return (NS_RETURN);
243	}
244	*((struct hostent **)rval) = hptr;
245	return (NS_SUCCESS);
246#else
247	*((struct hostent **)rval) = NULL;
248	return (NS_UNAVAIL);
249#endif
250}
251
252int
253_nis_gethostbyaddr(void *rval, void *cb_data, va_list ap)
254{
255#ifdef YP
256	const void *addr;
257	socklen_t len;
258	int af;
259	char *buffer;
260	size_t buflen;
261	int *errnop, *h_errnop;
262	struct hostent *hptr, he;
263	struct hostent_data *hed;
264	res_state statp;
265
266	addr = va_arg(ap, const void *);
267	len = va_arg(ap, socklen_t);
268	af = va_arg(ap, int);
269	hptr = va_arg(ap, struct hostent *);
270	buffer = va_arg(ap, char *);
271	buflen = va_arg(ap, size_t);
272	errnop = va_arg(ap, int *);
273	h_errnop = va_arg(ap, int *);
274
275	*((struct hostent **)rval) = NULL;
276
277	statp = __res_state();
278	if ((hed = __hostent_data_init()) == NULL) {
279		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
280		*h_errnop = statp->res_h_errno;
281		return (NS_NOTFOUND);
282	}
283
284	if (_gethostbynisaddr_r(addr, len, af, &he, hed) != 0) {
285		*h_errnop = statp->res_h_errno;
286		return (NS_NOTFOUND);
287	}
288	if (__copy_hostent(&he, hptr, buffer, buflen) != 0) {
289		*errnop = errno;
290		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
291		*h_errnop = statp->res_h_errno;
292		return (NS_RETURN);
293	}
294	*((struct hostent **)rval) = hptr;
295	return (NS_SUCCESS);
296#else
297	*((struct hostent **)rval) = NULL;
298	return (NS_UNAVAIL);
299#endif
300}
301