xref: /dragonfly/lib/libc/net/getnetnamadr.c (revision cf93a39f)
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  * $FreeBSD: src/lib/libc/net/getnetnamadr.c,v 1.23 2006/04/28 12:03:35 ume Exp $
26  */
27 
28 #include "namespace.h"
29 #include "reentrant.h"
30 #include <sys/param.h>
31 #include <sys/socket.h>
32 #include <netinet/in.h>
33 #include <arpa/inet.h>
34 #include <netdb.h>
35 #include <stdio.h>
36 #include <ctype.h>
37 #include <errno.h>
38 #include <stdlib.h>
39 #include <string.h>
40 #include <stdarg.h>
41 #include <nsswitch.h>
42 #include "un-namespace.h"
43 #include "netdb_private.h"
44 #ifdef NS_CACHING
45 #include "nscache.h"
46 #endif
47 
48 /* Network lookup order if nsswitch.conf is broken or nonexistant */
49 static const ns_src default_src[] = {
50 	{ NSSRC_FILES, NS_SUCCESS },
51 	{ NSSRC_DNS, NS_SUCCESS },
52 	{ 0 }
53 };
54 
55 NETDB_THREAD_ALLOC(netent_data)
NETDB_THREAD_ALLOC(netdata)56 NETDB_THREAD_ALLOC(netdata)
57 
58 #ifdef NS_CACHING
59 static int
60 net_id_func(char *buffer, size_t *buffer_size, va_list ap, void *cache_mdata)
61 {
62 	char *name;
63 	uint32_t net;
64 	int type;
65 
66 	size_t desired_size, size;
67 	enum nss_lookup_type lookup_type;
68 	int res = NS_UNAVAIL;
69 
70 	lookup_type = (enum nss_lookup_type)cache_mdata;
71 	switch (lookup_type) {
72 	case nss_lt_name:
73 		name = va_arg(ap, char *);
74 
75 		size = strlen(name);
76 		desired_size = sizeof(enum nss_lookup_type) + size + 1;
77 		if (desired_size > *buffer_size) {
78 			res = NS_RETURN;
79 			goto fin;
80 		}
81 
82 		memcpy(buffer, &lookup_type, sizeof(enum nss_lookup_type));
83 		memcpy(buffer + sizeof(enum nss_lookup_type), name, size + 1);
84 
85 		res = NS_SUCCESS;
86 		break;
87 	case nss_lt_id:
88 		net = va_arg(ap, uint32_t);
89 		type = va_arg(ap, int);
90 
91 		desired_size = sizeof(enum nss_lookup_type) +
92 		    sizeof(uint32_t) + sizeof(int);
93 		if (desired_size > *buffer_size) {
94 			res = NS_RETURN;
95 			goto fin;
96 		}
97 
98 		memcpy(buffer, &lookup_type, sizeof(enum nss_lookup_type));
99 		memcpy(buffer + sizeof(enum nss_lookup_type), &net,
100 		    sizeof(uint32_t));
101 		memcpy(buffer + sizeof(enum nss_lookup_type) + sizeof(uint32_t),
102 		    &type, sizeof(int));
103 
104 		res = NS_SUCCESS;
105 		break;
106 	default:
107 		/* should be unreachable */
108 		return (NS_UNAVAIL);
109 	}
110 
111 fin:
112 	*buffer_size = desired_size;
113 	return (res);
114 }
115 
116 
117 static int
net_marshal_func(char * buffer,size_t * buffer_size,void * retval __unused,va_list ap,void * cache_mdata)118 net_marshal_func(char *buffer, size_t *buffer_size, void *retval __unused,
119 		 va_list ap, void *cache_mdata)
120 {
121 	char *name __unused;
122 	uint32_t net __unused;
123 	int type __unused;
124 	struct netent *ne;
125 	char *orig_buf __unused;
126 	size_t orig_buf_size __unused;
127 
128 	struct netent new_ne;
129 	size_t desired_size, size, aliases_size;
130 	char *p;
131 	char **alias;
132 
133 	switch ((enum nss_lookup_type)cache_mdata) {
134 	case nss_lt_name:
135 		name = va_arg(ap, char *);
136 		break;
137 	case nss_lt_id:
138 		net = va_arg(ap, uint32_t);
139 		type = va_arg(ap, int);
140 	break;
141 	case nss_lt_all:
142 		break;
143 	default:
144 		/* should be unreachable */
145 		return (NS_UNAVAIL);
146 	}
147 
148 	ne = va_arg(ap, struct netent *);
149 	orig_buf = va_arg(ap, char *);
150 	orig_buf_size = va_arg(ap, size_t);
151 
152 	desired_size = _ALIGNBYTES + sizeof(struct netent) + sizeof(char *);
153 	if (ne->n_name != NULL)
154 		desired_size += strlen(ne->n_name) + 1;
155 
156 	if (ne->n_aliases != NULL) {
157 		aliases_size = 0;
158 		for (alias = ne->n_aliases; *alias; ++alias) {
159 			desired_size += strlen(*alias) + 1;
160 			++aliases_size;
161 		}
162 
163 		desired_size += _ALIGNBYTES +
164 		    (aliases_size + 1) * sizeof(char *);
165 	}
166 
167 	if (*buffer_size < desired_size) {
168 		/* this assignment is here for future use */
169 		*buffer_size = desired_size;
170 		return (NS_RETURN);
171 	}
172 
173 	memcpy(&new_ne, ne, sizeof(struct netent));
174 
175 	*buffer_size = desired_size;
176 	memset(buffer, 0, desired_size);
177 	p = buffer + sizeof(struct netent) + sizeof(char *);
178 	memcpy(buffer + sizeof(struct netent), &p, sizeof(char *));
179 	p = (char *)_ALIGN(p);
180 
181 	if (new_ne.n_name != NULL) {
182 		size = strlen(new_ne.n_name);
183 		memcpy(p, new_ne.n_name, size);
184 		new_ne.n_name = p;
185 		p += size + 1;
186 	}
187 
188 	if (new_ne.n_aliases != NULL) {
189 		p = (char *)_ALIGN(p);
190 		memcpy(p, new_ne.n_aliases, sizeof(char *) * aliases_size);
191 		new_ne.n_aliases = (char **)p;
192 		p += sizeof(char *) * (aliases_size + 1);
193 
194 		for (alias = new_ne.n_aliases; *alias; ++alias) {
195 			size = strlen(*alias);
196 			memcpy(p, *alias, size);
197 			*alias = p;
198 			p += size + 1;
199 		}
200 	}
201 
202 	memcpy(buffer, &new_ne, sizeof(struct netent));
203 	return (NS_SUCCESS);
204 }
205 
206 static int
net_unmarshal_func(char * buffer,size_t buffer_size,void * retval,va_list ap,void * cache_mdata)207 net_unmarshal_func(char *buffer, size_t buffer_size, void *retval, va_list ap,
208 		   void *cache_mdata)
209 {
210 	char *name __unused;
211 	uint32_t net __unused;
212 	int type __unused;
213 	struct netent *ne;
214 	char *orig_buf;
215 	size_t orig_buf_size;
216 	int *ret_errno;
217 
218 	char *p;
219 	char **alias;
220 
221 	switch ((enum nss_lookup_type)cache_mdata) {
222 	case nss_lt_name:
223 		name = va_arg(ap, char *);
224 		break;
225 	case nss_lt_id:
226 		net = va_arg(ap, uint32_t);
227 		type = va_arg(ap, int);
228 		break;
229 	case nss_lt_all:
230 		break;
231 	default:
232 		/* should be unreachable */
233 		return (NS_UNAVAIL);
234 	}
235 
236 	ne = va_arg(ap, struct netent *);
237 	orig_buf = va_arg(ap, char *);
238 	orig_buf_size = va_arg(ap, size_t);
239 	ret_errno = va_arg(ap, int *);
240 
241 	if (orig_buf_size <
242 	    buffer_size - sizeof(struct netent) - sizeof(char *)) {
243 		*ret_errno = ERANGE;
244 		return (NS_RETURN);
245 	}
246 
247 	memcpy(ne, buffer, sizeof(struct netent));
248 	memcpy(&p, buffer + sizeof(struct netent), sizeof(char *));
249 
250 	orig_buf = (char *)_ALIGN(orig_buf);
251 	memcpy(orig_buf, buffer + sizeof(struct netent) + sizeof(char *) +
252 	    _ALIGN(p) - (size_t)p,
253 	    buffer_size - sizeof(struct netent) - sizeof(char *) -
254 	    _ALIGN(p) + (size_t)p);
255 	p = (char *)_ALIGN(p);
256 
257 	NS_APPLY_OFFSET(ne->n_name, orig_buf, p, char *);
258 	if (ne->n_aliases != NULL) {
259 		NS_APPLY_OFFSET(ne->n_aliases, orig_buf, p, char **);
260 
261 		for (alias = ne->n_aliases; *alias; ++alias)
262 			NS_APPLY_OFFSET(*alias, orig_buf, p, char *);
263 	}
264 
265 	if (retval != NULL)
266 		*((struct netent **)retval) = ne;
267 
268 	return (NS_SUCCESS);
269 }
270 #endif /* NS_CACHING */
271 
272 static void
netent_data_free(void * ptr)273 netent_data_free(void *ptr)
274 {
275 	struct netent_data *ned = ptr;
276 
277 	if (ned == NULL)
278 		return;
279 	ned->stayopen = 0;
280 	_endnethtent(ned);
281 	free(ned);
282 }
283 
284 static void
netdata_free(void * ptr)285 netdata_free(void *ptr)
286 {
287 	free(ptr);
288 }
289 
290 int
__copy_netent(struct netent * ne,struct netent * nptr,char * buf,size_t buflen)291 __copy_netent(struct netent *ne, struct netent *nptr, char *buf, size_t buflen)
292 {
293 	char *cp;
294 	int i, n;
295 	int numptr, len;
296 
297 	/* Find out the amount of space required to store the answer. */
298 	numptr = 1; /* NULL ptr */
299 	len = (char *)ALIGN(buf) - buf;
300 	for (i = 0; ne->n_aliases[i]; i++, numptr++) {
301 		len += strlen(ne->n_aliases[i]) + 1;
302 	}
303 	len += strlen(ne->n_name) + 1;
304 	len += numptr * sizeof(char*);
305 
306 	if (len > (int)buflen) {
307 		errno = ERANGE;
308 		return (-1);
309 	}
310 
311 	/* copy net value and type */
312 	nptr->n_addrtype = ne->n_addrtype;
313 	nptr->n_net = ne->n_net;
314 
315 	cp = (char *)ALIGN(buf) + numptr * sizeof(char *);
316 
317 	/* copy official name */
318 	n = strlen(ne->n_name) + 1;
319 	strcpy(cp, ne->n_name);
320 	nptr->n_name = cp;
321 	cp += n;
322 
323 	/* copy aliases */
324 	nptr->n_aliases = (char **)ALIGN(buf);
325 	for (i = 0 ; ne->n_aliases[i]; i++) {
326 		n = strlen(ne->n_aliases[i]) + 1;
327 		strcpy(cp, ne->n_aliases[i]);
328 		nptr->n_aliases[i] = cp;
329 		cp += n;
330 	}
331 	nptr->n_aliases[i] = NULL;
332 
333 	return (0);
334 }
335 
336 int
getnetbyname_r(const char * name,struct netent * ne,char * buffer,size_t buflen,struct netent ** result,int * h_errnop)337 getnetbyname_r(const char *name, struct netent *ne, char *buffer,
338 	       size_t buflen, struct netent **result, int *h_errnop)
339 {
340 #ifdef NS_CACHING
341 	static const nss_cache_info cache_info =
342 		NS_COMMON_CACHE_INFO_INITIALIZER(
343 		networks, (void *)nss_lt_name,
344 		net_id_func, net_marshal_func, net_unmarshal_func);
345 #endif
346 	static const ns_dtab dtab[] = {
347 		NS_FILES_CB(_ht_getnetbyname, NULL)
348 		{ NSSRC_DNS, _dns_getnetbyname, NULL },
349 		NS_NIS_CB(_nis_getnetbyname, NULL) /* force -DHESIOD */
350 #ifdef NS_CACHING
351 		NS_CACHE_CB(&cache_info)
352 #endif
353 		{ 0 }
354 	};
355 	int rval, ret_errno;
356 
357 	rval = _nsdispatch((void *)result, dtab, NSDB_NETWORKS,
358 	    "getnetbyname_r", default_src, name, ne, buffer, buflen,
359 	    &ret_errno, h_errnop);
360 
361 	return ((rval == NS_SUCCESS) ? 0 : -1);
362 }
363 
364 int
getnetbyaddr_r(uint32_t addr,int af,struct netent * ne,char * buffer,size_t buflen,struct netent ** result,int * h_errnop)365 getnetbyaddr_r(uint32_t addr, int af, struct netent *ne, char *buffer,
366 	       size_t buflen, struct netent **result, int *h_errnop)
367 {
368 #ifdef NS_CACHING
369 	static const nss_cache_info cache_info =
370 		NS_COMMON_CACHE_INFO_INITIALIZER(
371 		networks, (void *)nss_lt_id,
372 		net_id_func, net_marshal_func, net_unmarshal_func);
373 #endif
374 	static const ns_dtab dtab[] = {
375 		NS_FILES_CB(_ht_getnetbyaddr, NULL)
376 		{ NSSRC_DNS, _dns_getnetbyaddr, NULL },
377 		NS_NIS_CB(_nis_getnetbyaddr, NULL) /* force -DHESIOD */
378 #ifdef NS_CACHING
379 		NS_CACHE_CB(&cache_info)
380 #endif
381 		{ 0 }
382 	};
383 	int rval, ret_errno;
384 
385 	rval = _nsdispatch((void *)result, dtab, NSDB_NETWORKS,
386 	    "getnetbyaddr_r", default_src, addr, af, ne, buffer, buflen,
387 	    &ret_errno, h_errnop);
388 
389 	return ((rval == NS_SUCCESS) ? 0 : -1);
390 }
391 
392 struct netent *
getnetbyname(const char * name)393 getnetbyname(const char *name)
394 {
395 	struct netdata *nd;
396 	struct netent *rval;
397 	int ret_h_errno;
398 
399 	if ((nd = __netdata_init()) == NULL)
400 		return (NULL);
401 	if (getnetbyname_r(name, &nd->net, nd->data, sizeof(nd->data), &rval,
402 	    &ret_h_errno) != 0)
403 		return (NULL);
404 	return (rval);
405 }
406 
407 struct netent *
getnetbyaddr(uint32_t addr,int af)408 getnetbyaddr(uint32_t addr, int af)
409 {
410 	struct netdata *nd;
411 	struct netent *rval;
412 	int ret_h_errno;
413 
414 	if ((nd = __netdata_init()) == NULL)
415 		return (NULL);
416 	if (getnetbyaddr_r(addr, af, &nd->net, nd->data, sizeof(nd->data),
417 	    &rval, &ret_h_errno) != 0)
418 		return (NULL);
419 	return (rval);
420 }
421 
422 void
setnetent(int stayopen)423 setnetent(int stayopen)
424 {
425 	struct netent_data *ned;
426 
427 	if ((ned = __netent_data_init()) == NULL)
428 		return;
429 	_setnethtent(stayopen, ned);
430 	_setnetdnsent(stayopen);
431 }
432 
433 void
endnetent(void)434 endnetent(void)
435 {
436 	struct netent_data *ned;
437 
438 	if ((ned = __netent_data_init()) == NULL)
439 		return;
440 	_endnethtent(ned);
441 	_endnetdnsent();
442 }
443