xref: /freebsd/lib/libc/net/getprotoent.c (revision dc36d6f9bb1753f3808552f3afd30eda9a7b206a)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1983, 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 
32 #include <sys/param.h>
33 #include <sys/socket.h>
34 #include <errno.h>
35 #include <limits.h>
36 #include <netdb.h>
37 #include <nsswitch.h>
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <string.h>
41 #include "namespace.h"
42 #include "reentrant.h"
43 #include "un-namespace.h"
44 #include "netdb_private.h"
45 #ifdef NS_CACHING
46 #include "nscache.h"
47 #endif
48 #include "nss_tls.h"
49 
50 static const ns_src defaultsrc[] = {
51 	{ NSSRC_FILES, NS_SUCCESS },
52 	{ NULL, 0 }
53 };
54 
55 NETDB_THREAD_ALLOC(protoent_data)
NETDB_THREAD_ALLOC(protodata)56 NETDB_THREAD_ALLOC(protodata)
57 
58 static void
59 protoent_data_clear(struct protoent_data *ped)
60 {
61 	if (ped->fp) {
62 		fclose(ped->fp);
63 		ped->fp = NULL;
64 	}
65 }
66 
67 static void
protoent_data_free(void * ptr)68 protoent_data_free(void *ptr)
69 {
70 	struct protoent_data *ped = ptr;
71 
72 	protoent_data_clear(ped);
73 	free(ped);
74 }
75 
76 static void
protodata_free(void * ptr)77 protodata_free(void *ptr)
78 {
79 	free(ptr);
80 }
81 
82 #ifdef NS_CACHING
83 int
__proto_id_func(char * buffer,size_t * buffer_size,va_list ap,void * cache_mdata)84 __proto_id_func(char *buffer, size_t *buffer_size, va_list ap,
85     void *cache_mdata)
86 {
87 	char *name;
88 	int proto;
89 
90 	size_t desired_size, size;
91 	enum nss_lookup_type lookup_type;
92 	int res = NS_UNAVAIL;
93 
94 	lookup_type = (enum nss_lookup_type)(uintptr_t)cache_mdata;
95 	switch (lookup_type) {
96 	case nss_lt_name:
97 		name = va_arg(ap, char *);
98 
99 		size = strlen(name);
100 		desired_size = sizeof(enum nss_lookup_type) + size + 1;
101 		if (desired_size > *buffer_size) {
102 			res = NS_RETURN;
103 			goto fin;
104 		}
105 
106 		memcpy(buffer, &lookup_type, sizeof(enum nss_lookup_type));
107 		memcpy(buffer + sizeof(enum nss_lookup_type), name, size + 1);
108 
109 		res = NS_SUCCESS;
110 		break;
111 	case nss_lt_id:
112 		proto = va_arg(ap, int);
113 
114 		desired_size = sizeof(enum nss_lookup_type) + sizeof(int);
115 		if (desired_size > *buffer_size) {
116 			res = NS_RETURN;
117 			goto fin;
118 		}
119 
120 		memcpy(buffer, &lookup_type, sizeof(enum nss_lookup_type));
121 		memcpy(buffer + sizeof(enum nss_lookup_type), &proto,
122 			sizeof(int));
123 
124 		res = NS_SUCCESS;
125 		break;
126 	default:
127 		/* should be unreachable */
128 		return (NS_UNAVAIL);
129 	}
130 
131 fin:
132 	*buffer_size = desired_size;
133 	return (res);
134 }
135 
136 
137 int
__proto_marshal_func(char * buffer,size_t * buffer_size,void * retval,va_list ap,void * cache_mdata)138 __proto_marshal_func(char *buffer, size_t *buffer_size, void *retval,
139     va_list ap, void *cache_mdata)
140 {
141 	char *name __unused;
142 	int num __unused;
143 	struct protoent *proto;
144 	char *orig_buf __unused;
145 	size_t orig_buf_size __unused;
146 
147 	struct protoent new_proto;
148 	size_t desired_size, size, aliases_size;
149 	char *p;
150 	char **alias;
151 
152 	switch ((enum nss_lookup_type)(uintptr_t)cache_mdata) {
153 	case nss_lt_name:
154 		name = va_arg(ap, char *);
155 		break;
156 	case nss_lt_id:
157 		num = va_arg(ap, int);
158 		break;
159 	case nss_lt_all:
160 		break;
161 	default:
162 		/* should be unreachable */
163 		return (NS_UNAVAIL);
164 	}
165 
166 	proto = va_arg(ap, struct protoent *);
167 	orig_buf = va_arg(ap, char *);
168 	orig_buf_size = va_arg(ap, size_t);
169 
170 	desired_size = _ALIGNBYTES + sizeof(struct protoent) + sizeof(char *);
171 	if (proto->p_name != NULL)
172 		desired_size += strlen(proto->p_name) + 1;
173 
174 	if (proto->p_aliases != NULL) {
175 		aliases_size = 0;
176 		for (alias = proto->p_aliases; *alias; ++alias) {
177 			desired_size += strlen(*alias) + 1;
178 			++aliases_size;
179 		}
180 
181 		desired_size += _ALIGNBYTES + (aliases_size + 1) *
182 		    sizeof(char *);
183 	}
184 
185 	if (*buffer_size < desired_size) {
186 		/* this assignment is here for future use */
187 		*buffer_size = desired_size;
188 		return (NS_RETURN);
189 	}
190 
191 	memcpy(&new_proto, proto, sizeof(struct protoent));
192 
193 	*buffer_size = desired_size;
194 	memset(buffer, 0, desired_size);
195 	p = buffer + sizeof(struct protoent) + sizeof(char *);
196 	memcpy(buffer + sizeof(struct protoent), &p, sizeof(char *));
197 	p = (char *)_ALIGN(p);
198 
199 	if (new_proto.p_name != NULL) {
200 		size = strlen(new_proto.p_name);
201 		memcpy(p, new_proto.p_name, size);
202 		new_proto.p_name = p;
203 		p += size + 1;
204 	}
205 
206 	if (new_proto.p_aliases != NULL) {
207 		p = (char *)_ALIGN(p);
208 		memcpy(p, new_proto.p_aliases, sizeof(char *) * aliases_size);
209 		new_proto.p_aliases = (char **)p;
210 		p += sizeof(char *) * (aliases_size + 1);
211 
212 		for (alias = new_proto.p_aliases; *alias; ++alias) {
213 			size = strlen(*alias);
214 			memcpy(p, *alias, size);
215 			*alias = p;
216 			p += size + 1;
217 		}
218 	}
219 
220 	memcpy(buffer, &new_proto, sizeof(struct protoent));
221 	return (NS_SUCCESS);
222 }
223 
224 int
__proto_unmarshal_func(char * buffer,size_t buffer_size,void * retval,va_list ap,void * cache_mdata)225 __proto_unmarshal_func(char *buffer, size_t buffer_size, void *retval,
226     va_list ap, void *cache_mdata)
227 {
228 	char *name __unused;
229 	int num __unused;
230 	struct protoent *proto;
231 	char *orig_buf;
232 	size_t orig_buf_size;
233 	int *ret_errno;
234 
235 	char *p;
236 	char **alias;
237 
238 	switch ((enum nss_lookup_type)(uintptr_t)cache_mdata) {
239 	case nss_lt_name:
240 		name = va_arg(ap, char *);
241 		break;
242 	case nss_lt_id:
243 		num = va_arg(ap, int);
244 		break;
245 	case nss_lt_all:
246 		break;
247 	default:
248 		/* should be unreachable */
249 		return (NS_UNAVAIL);
250 	}
251 
252 	proto = va_arg(ap, struct protoent *);
253 	orig_buf = va_arg(ap, char *);
254 	orig_buf_size = va_arg(ap, size_t);
255 	ret_errno = va_arg(ap, int *);
256 
257 	if (orig_buf_size <
258 	    buffer_size - sizeof(struct protoent) - sizeof(char *)) {
259 		*ret_errno = ERANGE;
260 		return (NS_RETURN);
261 	}
262 
263 	memcpy(proto, buffer, sizeof(struct protoent));
264 	memcpy(&p, buffer + sizeof(struct protoent), sizeof(char *));
265 
266 	orig_buf = (char *)_ALIGN(orig_buf);
267 	memcpy(orig_buf, buffer + sizeof(struct protoent) + sizeof(char *) +
268 	    _ALIGN(p) - (size_t)p,
269 	    buffer_size - sizeof(struct protoent) - sizeof(char *) -
270 	    _ALIGN(p) + (size_t)p);
271 	p = (char *)_ALIGN(p);
272 
273 	NS_APPLY_OFFSET(proto->p_name, orig_buf, p, char *);
274 	if (proto->p_aliases != NULL) {
275 		NS_APPLY_OFFSET(proto->p_aliases, orig_buf, p, char **);
276 
277 		for (alias = proto->p_aliases; *alias; ++alias)
278 			NS_APPLY_OFFSET(*alias, orig_buf, p, char *);
279 	}
280 
281 	if (retval != NULL)
282 		*((struct protoent **)retval) = proto;
283 
284 	return (NS_SUCCESS);
285 }
286 
287 NSS_MP_CACHE_HANDLING(protocols);
288 #endif /* NS_CACHING */
289 
290 int
__copy_protoent(struct protoent * pe,struct protoent * pptr,char * buf,size_t buflen)291 __copy_protoent(struct protoent *pe, struct protoent *pptr, char *buf,
292     size_t buflen)
293 {
294 	char *cp;
295 	int i, n;
296 	int numptr, len;
297 
298 	/* Find out the amount of space required to store the answer. */
299 	numptr = 1; /* NULL ptr */
300 	len = (char *)ALIGN(buf) - buf;
301 	for (i = 0; pe->p_aliases[i]; i++, numptr++) {
302 		len += strlen(pe->p_aliases[i]) + 1;
303 	}
304 	len += strlen(pe->p_name) + 1;
305 	len += numptr * sizeof(char*);
306 
307 	if (len > (int)buflen) {
308 		errno = ERANGE;
309 		return (-1);
310 	}
311 
312 	/* copy protocol value*/
313 	pptr->p_proto = pe->p_proto;
314 
315 	cp = (char *)ALIGN(buf) + numptr * sizeof(char *);
316 
317 	/* copy official name */
318 	n = strlen(pe->p_name) + 1;
319 	strcpy(cp, pe->p_name);
320 	pptr->p_name = cp;
321 	cp += n;
322 
323 	/* copy aliases */
324 	pptr->p_aliases = (char **)ALIGN(buf);
325 	for (i = 0 ; pe->p_aliases[i]; i++) {
326 		n = strlen(pe->p_aliases[i]) + 1;
327 		strcpy(cp, pe->p_aliases[i]);
328 		pptr->p_aliases[i] = cp;
329 		cp += n;
330 	}
331 	pptr->p_aliases[i] = NULL;
332 
333 	return (0);
334 }
335 
336 void
__setprotoent_p(int f,struct protoent_data * ped)337 __setprotoent_p(int f, struct protoent_data *ped)
338 {
339 	if (ped->fp == NULL)
340 		ped->fp = fopen(_PATH_PROTOCOLS, "re");
341 	else
342 		rewind(ped->fp);
343 	ped->stayopen |= f;
344 }
345 
346 void
__endprotoent_p(struct protoent_data * ped)347 __endprotoent_p(struct protoent_data *ped)
348 {
349 	if (ped->fp) {
350 		fclose(ped->fp);
351 		ped->fp = NULL;
352 	}
353 	ped->stayopen = 0;
354 }
355 
356 int
__getprotoent_p(struct protoent * pe,struct protoent_data * ped)357 __getprotoent_p(struct protoent *pe, struct protoent_data *ped)
358 {
359 	char *p;
360 	char *cp, **q, *endp;
361 	long l;
362 
363 	if (ped->fp == NULL && (ped->fp = fopen(_PATH_PROTOCOLS, "re")) == NULL)
364 		return (-1);
365 again:
366 	if ((p = fgets(ped->line, sizeof ped->line, ped->fp)) == NULL)
367 		return (-1);
368 	if (*p == '#')
369 		goto again;
370 	cp = strpbrk(p, "#\n");
371 	if (cp != NULL)
372 		*cp = '\0';
373 	pe->p_name = p;
374 	cp = strpbrk(p, " \t");
375 	if (cp == NULL)
376 		goto again;
377 	*cp++ = '\0';
378 	while (*cp == ' ' || *cp == '\t')
379 		cp++;
380 	p = strpbrk(cp, " \t");
381 	if (p != NULL)
382 		*p++ = '\0';
383 	l = strtol(cp, &endp, 10);
384 	if (endp == cp || *endp != '\0' || l < 0 || l > USHRT_MAX)
385 		goto again;
386 	pe->p_proto = l;
387 	q = pe->p_aliases = ped->aliases;
388 	if (p != NULL) {
389 		cp = p;
390 		while (cp && *cp) {
391 			if (*cp == ' ' || *cp == '\t') {
392 				cp++;
393 				continue;
394 			}
395 			if (q < &ped->aliases[_MAXALIASES - 1])
396 				*q++ = cp;
397 			cp = strpbrk(cp, " \t");
398 			if (cp != NULL)
399 				*cp++ = '\0';
400 		}
401 	}
402 	*q = NULL;
403 	return (0);
404 }
405 
406 static int
files_getprotoent_r(void * retval,void * mdata,va_list ap)407 files_getprotoent_r(void *retval, void *mdata, va_list ap)
408 {
409 	struct protoent pe;
410 	struct protoent_data *ped;
411 
412 	struct protoent	*pptr;
413 	char *buffer;
414 	size_t buflen;
415 	int *errnop;
416 
417 	pptr = va_arg(ap, struct protoent *);
418 	buffer = va_arg(ap, char *);
419 	buflen = va_arg(ap, size_t);
420 	errnop = va_arg(ap, int *);
421 
422 	if ((ped = __protoent_data_init()) == NULL) {
423 		*errnop = errno;
424 		return (NS_NOTFOUND);
425 	}
426 
427 	if (__getprotoent_p(&pe, ped) != 0) {
428 		*errnop = errno;
429 		return (NS_NOTFOUND);
430 	}
431 
432 	if (__copy_protoent(&pe, pptr, buffer, buflen) != 0) {
433 		*errnop = errno;
434 		return (NS_RETURN);
435 	}
436 
437 	*((struct protoent **)retval) = pptr;
438 	return (NS_SUCCESS);
439 }
440 
441 static int
files_setprotoent(void * retval,void * mdata,va_list ap)442 files_setprotoent(void *retval, void *mdata, va_list ap)
443 {
444 	struct protoent_data *ped;
445 	int f;
446 
447 	f = va_arg(ap, int);
448 	if ((ped = __protoent_data_init()) == NULL)
449 		return (NS_UNAVAIL);
450 
451 	__setprotoent_p(f, ped);
452 	return (NS_UNAVAIL);
453 }
454 
455 static int
files_endprotoent(void * retval,void * mdata,va_list ap)456 files_endprotoent(void *retval, void *mdata, va_list ap)
457 {
458 	struct protoent_data *ped;
459 
460 	if ((ped = __protoent_data_init()) == NULL)
461 		return (NS_UNAVAIL);
462 
463 	__endprotoent_p(ped);
464 	return (NS_UNAVAIL);
465 }
466 
467 int
getprotoent_r(struct protoent * pptr,char * buffer,size_t buflen,struct protoent ** result)468 getprotoent_r(struct protoent *pptr, char *buffer, size_t buflen,
469     struct protoent **result)
470 {
471 #ifdef NS_CACHING
472 	static const nss_cache_info cache_info = NS_MP_CACHE_INFO_INITIALIZER(
473 		protocols, (void *)nss_lt_all,
474 		__proto_marshal_func, __proto_unmarshal_func);
475 #endif
476 	static const ns_dtab dtab[] = {
477 		{ NSSRC_FILES, files_getprotoent_r, (void *)nss_lt_all },
478 #ifdef NS_CACHING
479 		NS_CACHE_CB(&cache_info)
480 #endif
481 		{ NULL, NULL, NULL }
482 	};
483 	int rv, ret_errno;
484 
485 	ret_errno = 0;
486 	*result = NULL;
487 	rv = nsdispatch(result, dtab, NSDB_PROTOCOLS, "getprotoent_r",
488 	    defaultsrc, pptr, buffer, buflen, &ret_errno);
489 
490 	if (rv != NS_SUCCESS) {
491 		errno = ret_errno;
492 		return (ret_errno);
493 	}
494 	return (0);
495 }
496 
497 void
setprotoent(int stayopen)498 setprotoent(int stayopen)
499 {
500 #ifdef NS_CACHING
501 	static const nss_cache_info cache_info = NS_MP_CACHE_INFO_INITIALIZER(
502 		protocols, (void *)nss_lt_all,
503 		NULL, NULL);
504 #endif
505 
506 	static const ns_dtab dtab[] = {
507 		{ NSSRC_FILES, files_setprotoent, NULL },
508 #ifdef NS_CACHING
509 		NS_CACHE_CB(&cache_info)
510 #endif
511 		{ NULL, NULL, NULL }
512 	};
513 
514 	(void)nsdispatch(NULL, dtab, NSDB_PROTOCOLS, "setprotoent", defaultsrc,
515 		stayopen);
516 }
517 
518 void
endprotoent(void)519 endprotoent(void)
520 {
521 #ifdef NS_CACHING
522 	static const nss_cache_info cache_info = NS_MP_CACHE_INFO_INITIALIZER(
523 		protocols, (void *)nss_lt_all,
524 		NULL, NULL);
525 #endif
526 
527 	static const ns_dtab dtab[] = {
528 		{ NSSRC_FILES, files_endprotoent, NULL },
529 #ifdef NS_CACHING
530 		NS_CACHE_CB(&cache_info)
531 #endif
532 		{ NULL, NULL, NULL }
533 	};
534 
535 	(void)nsdispatch(NULL, dtab, NSDB_PROTOCOLS, "endprotoent", defaultsrc);
536 }
537 
538 struct protoent *
getprotoent(void)539 getprotoent(void)
540 {
541 	struct protodata *pd;
542 	struct protoent *rval;
543 
544 	if ((pd = __protodata_init()) == NULL)
545 		return (NULL);
546 	if (getprotoent_r(&pd->proto, pd->data, sizeof(pd->data), &rval) != 0)
547 		return (NULL);
548 	return (rval);
549 }
550