xref: /freebsd/lib/libc/net/gethostbynis.c (revision 87569f75a91f298c52a71823c04d41cf53c88889)
1 /*-
2  * Copyright (c) 1994, Garrett Wollman
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS ``AS IS'' AND
14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  */
25 
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
28 
29 #include <sys/param.h>
30 #include <sys/socket.h>
31 #include <netinet/in.h>
32 #include <arpa/inet.h>
33 #include <arpa/nameser.h>
34 #include <netdb.h>
35 #include <stdio.h>
36 #include <stdlib.h>
37 #include <ctype.h>
38 #include <errno.h>
39 #include <string.h>
40 #include <stdarg.h>
41 #include <nsswitch.h>
42 #include <resolv.h>		/* XXX */
43 #ifdef YP
44 #include <rpc/rpc.h>
45 #include <rpcsvc/yp_prot.h>
46 #include <rpcsvc/ypclnt.h>
47 #endif
48 #include "netdb_private.h"
49 
50 #ifdef YP
51 static int
52 _gethostbynis(const char *name, char *map, int af, struct hostent *he,
53     struct hostent_data *hed)
54 {
55 	char *p, *bp, *ep;
56 	char *cp, **q;
57 	char *result;
58 	int resultlen, size, addrok = 0;
59 	char ypbuf[YPMAXRECORD + 2];
60 
61 	switch(af) {
62 	case AF_INET:
63 		size = NS_INADDRSZ;
64 		break;
65 	case AF_INET6:
66 		size = NS_IN6ADDRSZ;
67 		break;
68 	default:
69 		errno = EAFNOSUPPORT;
70 		h_errno = NETDB_INTERNAL;
71 		return -1;
72 	}
73 
74 	if (hed->yp_domain == (char *)NULL)
75 		if (yp_get_default_domain (&hed->yp_domain)) {
76 			h_errno = NETDB_INTERNAL;
77 			return -1;
78 		}
79 
80 	if (yp_match(hed->yp_domain, map, name, strlen(name), &result,
81 	    &resultlen)) {
82 		h_errno = HOST_NOT_FOUND;
83 		return -1;
84 	}
85 
86 	/* avoid potential memory leak */
87 	bcopy((char *)result, (char *)&ypbuf, resultlen);
88 	ypbuf[resultlen] = '\0';
89 	free(result);
90 	result = (char *)&ypbuf;
91 
92 	if ((cp = index(result, '\n')))
93 		*cp = '\0';
94 
95 	cp = strpbrk(result, " \t");
96 	*cp++ = '\0';
97 	he->h_addr_list = hed->h_addr_ptrs;
98 	he->h_addr = (char *)hed->host_addr;
99 	switch (af) {
100 	case AF_INET:
101 		addrok = inet_aton(result, (struct in_addr *)hed->host_addr);
102 		if (addrok != 1)
103 			break;
104 		if (_res.options & RES_USE_INET6) {
105 			_map_v4v6_address((char *)hed->host_addr,
106 			    (char *)hed->host_addr);
107 			af = AF_INET6;
108 			size = NS_IN6ADDRSZ;
109 		}
110 		break;
111 	case AF_INET6:
112 		addrok = inet_pton(af, result, hed->host_addr);
113 		break;
114 	}
115 	if (addrok != 1) {
116 		h_errno = HOST_NOT_FOUND;
117 		return -1;
118 	}
119 	he->h_addr_list[1] = NULL;
120 	he->h_length = size;
121 	he->h_addrtype = af;
122 	while (*cp == ' ' || *cp == '\t')
123 		cp++;
124 	bp = hed->hostbuf;
125 	ep = hed->hostbuf + sizeof hed->hostbuf;
126 	he->h_name = bp;
127 	q = he->h_aliases = hed->host_aliases;
128 	p = strpbrk(cp, " \t");
129 	if (p != NULL)
130 		*p++ = '\0';
131 	size = strlen(cp) + 1;
132 	if (ep - bp < size) {
133 		h_errno = NO_RECOVERY;
134 		return -1;
135 	}
136 	strlcpy(bp, cp, ep - bp);
137 	bp += size;
138 	cp = p;
139 	while (cp && *cp) {
140 		if (*cp == ' ' || *cp == '\t') {
141 			cp++;
142 			continue;
143 		}
144 		if (q >= &hed->host_aliases[_MAXALIASES - 1])
145 			break;
146 		p = strpbrk(cp, " \t");
147 		if (p != NULL)
148 			*p++ = '\0';
149 		size = strlen(cp) + 1;
150 		if (ep - bp < size)
151 			break;
152 		strlcpy(bp, cp, ep - bp);
153 		*q++ = bp;
154 		bp += size;
155 		cp = p;
156 	}
157 	*q = NULL;
158 	return 0;
159 }
160 
161 static int
162 _gethostbynisname_r(const char *name, int af, struct hostent *he,
163     struct hostent_data *hed)
164 {
165 	char *map;
166 
167 	switch (af) {
168 	case AF_INET:
169 		map = "hosts.byname";
170 		break;
171 	default:
172 		map = "ipnodes.byname";
173 		break;
174 	}
175 	return _gethostbynis(name, map, af, he, hed);
176 }
177 
178 static int
179 _gethostbynisaddr_r(const char *addr, int len, int af, struct hostent *he,
180     struct hostent_data *hed)
181 {
182 	char *map;
183 	char numaddr[46];
184 
185 	switch (af) {
186 	case AF_INET:
187 		map = "hosts.byaddr";
188 		break;
189 	default:
190 		map = "ipnodes.byaddr";
191 		break;
192 	}
193 	if (inet_ntop(af, addr, numaddr, sizeof(numaddr)) == NULL)
194 		return -1;
195 	return _gethostbynis(numaddr, map, af, he, hed);
196 }
197 #endif /* YP */
198 
199 /* XXX _gethostbynisname/_gethostbynisaddr only used by getipnodeby*() */
200 struct hostent *
201 _gethostbynisname(const char *name, int af)
202 {
203 #ifdef YP
204 	struct hostdata *hd;
205 	u_long oresopt;
206 	int error;
207 
208 	if ((hd = __hostdata_init()) == NULL) {
209 		h_errno = NETDB_INTERNAL;
210 		return NULL;
211 	}
212 	oresopt = _res.options;
213 	_res.options &= ~RES_USE_INET6;
214 	error = _gethostbynisname_r(name, af, &hd->host, &hd->data);
215 	_res.options = oresopt;
216 	return (error == 0) ? &hd->host : NULL;
217 #else
218 	return NULL;
219 #endif
220 }
221 
222 struct hostent *
223 _gethostbynisaddr(const char *addr, int len, int af)
224 {
225 #ifdef YP
226 	struct hostdata *hd;
227 	u_long oresopt;
228 	int error;
229 
230 	if ((hd = __hostdata_init()) == NULL) {
231 		h_errno = NETDB_INTERNAL;
232 		return NULL;
233 	}
234 	oresopt = _res.options;
235 	_res.options &= ~RES_USE_INET6;
236 	error = _gethostbynisaddr_r(addr, len, af, &hd->host, &hd->data);
237 	_res.options = oresopt;
238 	return (error == 0) ? &hd->host : NULL;
239 #else
240 	return NULL;
241 #endif
242 }
243 
244 int
245 _nis_gethostbyname(void *rval, void *cb_data, va_list ap)
246 {
247 #ifdef YP
248 	const char *name;
249 	int af;
250 	struct hostent *he;
251 	struct hostent_data *hed;
252 	int error;
253 
254 	name = va_arg(ap, const char *);
255 	af = va_arg(ap, int);
256 	he = va_arg(ap, struct hostent *);
257 	hed = va_arg(ap, struct hostent_data *);
258 
259 	error = _gethostbynisname_r(name, af, he, hed);
260 	return (error == 0) ? NS_SUCCESS : NS_NOTFOUND;
261 #else
262 	return NS_UNAVAIL;
263 #endif
264 }
265 
266 int
267 _nis_gethostbyaddr(void *rval, void *cb_data, va_list ap)
268 {
269 #ifdef YP
270 	const char *addr;
271 	int len;
272 	int af;
273 	struct hostent *he;
274 	struct hostent_data *hed;
275 	int error;
276 
277 	addr = va_arg(ap, const char *);
278 	len = va_arg(ap, int);
279 	af = va_arg(ap, int);
280 	he = va_arg(ap, struct hostent *);
281 	hed = va_arg(ap, struct hostent_data *);
282 
283 	error = _gethostbynisaddr_r(addr, len, af, he, hed);
284 	return (error == 0) ? NS_SUCCESS : NS_NOTFOUND;
285 #else
286 	return NS_UNAVAIL;
287 #endif
288 }
289