xref: /freebsd/lib/libc/gen/getgrent.c (revision 559a218c9b257775fb249b67945fe4a05b7a6b9f)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2003 Networks Associates Technology, Inc.
5  * All rights reserved.
6  *
7  * This software was developed for the FreeBSD Project by
8  * Jacques A. Vidrine, Safeport Network Services, and Network
9  * Associates Laboratories, the Security Research Division of Network
10  * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035
11  * ("CBOSS"), as part of the DARPA CHATS research program.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  */
35 #include "namespace.h"
36 #include <sys/param.h>
37 #ifdef YP
38 #include <rpc/rpc.h>
39 #include <rpcsvc/yp_prot.h>
40 #include <rpcsvc/ypclnt.h>
41 #endif
42 #include <assert.h>
43 #include <ctype.h>
44 #include <errno.h>
45 #ifdef HESIOD
46 #include <hesiod.h>
47 #endif
48 #include <grp.h>
49 #include <nsswitch.h>
50 #include <pthread.h>
51 #include <pthread_np.h>
52 #include <stdio.h>
53 #include <stdlib.h>
54 #include <string.h>
55 #include <syslog.h>
56 #include <unistd.h>
57 #include "un-namespace.h"
58 #include "libc_private.h"
59 #include "nss_tls.h"
60 #ifdef NS_CACHING
61 #include "nscache.h"
62 #endif
63 
64 enum constants {
65 	GRP_STORAGE_INITIAL	= 1 << 10, /* 1 KByte */
66 	GRP_STORAGE_MAX		= 1 << 20, /* 1 MByte */
67 	SETGRENT		= 1,
68 	ENDGRENT		= 2,
69 	HESIOD_NAME_MAX		= 256,
70 };
71 
72 static const ns_src defaultsrc[] = {
73 	{ NSSRC_COMPAT, NS_SUCCESS },
74 	{ NULL, 0 }
75 };
76 
77 int	 __getgroupmembership(const char *, gid_t, gid_t *, int, int *);
78 int	 __gr_match_entry(const char *, size_t, enum nss_lookup_type,
79 	    const char *, gid_t);
80 int	 __gr_parse_entry(char *, size_t, struct group *, char *, size_t,
81 	    int *);
82 
83 static	int	 is_comment_line(const char *, size_t);
84 
85 union key {
86 	const char	*name;
87 	gid_t		 gid;
88 };
89 static	struct group *getgr(int (*)(union key, struct group *, char *, size_t,
90 		    struct group **), union key);
91 static	int	 wrap_getgrnam_r(union key, struct group *, char *, size_t,
92 		    struct group **);
93 static	int	 wrap_getgrgid_r(union key, struct group *, char *, size_t,
94 		    struct group **);
95 static	int	 wrap_getgrent_r(union key, struct group *, char *, size_t,
96 		    struct group **);
97 
98 struct files_state {
99 	FILE	*fp;
100 	int	 stayopen;
101 };
102 static	void	 files_endstate(void *);
103 NSS_TLS_HANDLING(files);
104 static	int	 files_setgrent(void *, void *, va_list);
105 static	int	 files_group(void *, void *, va_list);
106 
107 
108 #ifdef HESIOD
109 struct dns_state {
110 	long	counter;
111 };
112 static	void	 dns_endstate(void *);
113 NSS_TLS_HANDLING(dns);
114 static	int	 dns_setgrent(void *, void *, va_list);
115 static	int	 dns_group(void *, void *, va_list);
116 #endif
117 
118 
119 #ifdef YP
120 struct nis_state {
121 	char	 domain[MAXHOSTNAMELEN];
122 	int	 done;
123 	char	*key;
124 	int	 keylen;
125 };
126 static	void	 nis_endstate(void *);
127 NSS_TLS_HANDLING(nis);
128 static	int	 nis_setgrent(void *, void *, va_list);
129 static	int	 nis_group(void *, void *, va_list);
130 #endif
131 
132 struct compat_state {
133 	FILE	*fp;
134 	int	 stayopen;
135 	char	*name;
136 	enum _compat {
137 		COMPAT_MODE_OFF = 0,
138 		COMPAT_MODE_ALL,
139 		COMPAT_MODE_NAME
140 	}	 compat;
141 };
142 static	void	 compat_endstate(void *);
143 NSS_TLS_HANDLING(compat);
144 static	int	 compat_setgrent(void *, void *, va_list);
145 static	int	 compat_group(void *, void *, va_list);
146 
147 static	int	gr_addgid(gid_t, gid_t *, int, int *);
148 static	int	getgroupmembership_fallback(void *, void *, va_list);
149 
150 #ifdef NS_CACHING
151 static	int	 grp_id_func(char *, size_t *, va_list, void *);
152 static	int	 grp_marshal_func(char *, size_t *, void *, va_list, void *);
153 static	int	 grp_unmarshal_func(char *, size_t, void *, va_list, void *);
154 
155 static int
grp_id_func(char * buffer,size_t * buffer_size,va_list ap,void * cache_mdata)156 grp_id_func(char *buffer, size_t *buffer_size, va_list ap, void *cache_mdata)
157 {
158 	char	*name;
159 	gid_t	gid;
160 
161 	size_t	desired_size, size;
162 	int	res = NS_UNAVAIL;
163 	enum nss_lookup_type lookup_type;
164 
165 
166 	lookup_type = (enum nss_lookup_type)(uintptr_t)cache_mdata;
167 	switch (lookup_type) {
168 	case nss_lt_name:
169 		name = va_arg(ap, char *);
170 		size = strlen(name);
171 		desired_size = sizeof(enum nss_lookup_type) + size + 1;
172 		if (desired_size > *buffer_size) {
173 			res = NS_RETURN;
174 			goto fin;
175 		}
176 
177 		memcpy(buffer, &lookup_type, sizeof(enum nss_lookup_type));
178 		memcpy(buffer + sizeof(enum nss_lookup_type), name, size + 1);
179 
180 		res = NS_SUCCESS;
181 		break;
182 	case nss_lt_id:
183 		gid = va_arg(ap, gid_t);
184 		desired_size = sizeof(enum nss_lookup_type) + sizeof(gid_t);
185 		if (desired_size > *buffer_size) {
186 			res = NS_RETURN;
187 			goto fin;
188 		}
189 
190 		memcpy(buffer, &lookup_type, sizeof(enum nss_lookup_type));
191 		memcpy(buffer + sizeof(enum nss_lookup_type), &gid,
192 		    sizeof(gid_t));
193 
194 		res = NS_SUCCESS;
195 		break;
196 	default:
197 		/* should be unreachable */
198 		return (NS_UNAVAIL);
199 	}
200 
201 fin:
202 	*buffer_size = desired_size;
203 	return (res);
204 }
205 
206 static int
grp_marshal_func(char * buffer,size_t * buffer_size,void * retval,va_list ap,void * cache_mdata)207 grp_marshal_func(char *buffer, size_t *buffer_size, void *retval, va_list ap,
208     void *cache_mdata)
209 {
210 	char *name __unused;
211 	gid_t gid __unused;
212 	struct group *grp;
213 	char *orig_buf __unused;
214 	size_t orig_buf_size __unused;
215 	struct group new_grp;
216 	size_t desired_size, size, mem_size;
217 	char *p, **mem;
218 
219 	switch ((enum nss_lookup_type)(uintptr_t)cache_mdata) {
220 	case nss_lt_name:
221 		name = va_arg(ap, char *);
222 		break;
223 	case nss_lt_id:
224 		gid = va_arg(ap, gid_t);
225 		break;
226 	case nss_lt_all:
227 		break;
228 	default:
229 		/* should be unreachable */
230 		return (NS_UNAVAIL);
231 	}
232 
233 	grp = va_arg(ap, struct group *);
234 	orig_buf = va_arg(ap, char *);
235 	orig_buf_size = va_arg(ap, size_t);
236 
237 	desired_size = _ALIGNBYTES + sizeof(struct group) + sizeof(char *);
238 
239 	if (grp->gr_name != NULL)
240 		desired_size += strlen(grp->gr_name) + 1;
241 	if (grp->gr_passwd != NULL)
242 		desired_size += strlen(grp->gr_passwd) + 1;
243 
244 	if (grp->gr_mem != NULL) {
245 		mem_size = 0;
246 		for (mem = grp->gr_mem; *mem; ++mem) {
247 			desired_size += strlen(*mem) + 1;
248 			++mem_size;
249 		}
250 
251 		desired_size += _ALIGNBYTES + (mem_size + 1) * sizeof(char *);
252 	}
253 
254 	if (desired_size > *buffer_size) {
255 		/* this assignment is here for future use */
256 		*buffer_size = desired_size;
257 		return (NS_RETURN);
258 	}
259 
260 	memcpy(&new_grp, grp, sizeof(struct group));
261 	memset(buffer, 0, desired_size);
262 
263 	*buffer_size = desired_size;
264 	p = buffer + sizeof(struct group) + sizeof(char *);
265 	memcpy(buffer + sizeof(struct group), &p, sizeof(char *));
266 	p = (char *)_ALIGN(p);
267 
268 	if (new_grp.gr_name != NULL) {
269 		size = strlen(new_grp.gr_name);
270 		memcpy(p, new_grp.gr_name, size);
271 		new_grp.gr_name = p;
272 		p += size + 1;
273 	}
274 
275 	if (new_grp.gr_passwd != NULL) {
276 		size = strlen(new_grp.gr_passwd);
277 		memcpy(p, new_grp.gr_passwd, size);
278 		new_grp.gr_passwd = p;
279 		p += size + 1;
280 	}
281 
282 	if (new_grp.gr_mem != NULL) {
283 		p = (char *)_ALIGN(p);
284 		memcpy(p, new_grp.gr_mem, sizeof(char *) * mem_size);
285 		new_grp.gr_mem = (char **)p;
286 		p += sizeof(char *) * (mem_size + 1);
287 
288 		for (mem = new_grp.gr_mem; *mem; ++mem) {
289 			size = strlen(*mem);
290 			memcpy(p, *mem, size);
291 			*mem = p;
292 			p += size + 1;
293 		}
294 	}
295 
296 	memcpy(buffer, &new_grp, sizeof(struct group));
297 	return (NS_SUCCESS);
298 }
299 
300 static int
grp_unmarshal_func(char * buffer,size_t buffer_size,void * retval,va_list ap,void * cache_mdata)301 grp_unmarshal_func(char *buffer, size_t buffer_size, void *retval, va_list ap,
302     void *cache_mdata)
303 {
304 	char *name __unused;
305 	gid_t gid __unused;
306 	struct group *grp;
307 	char *orig_buf;
308 	size_t orig_buf_size;
309 	int *ret_errno;
310 
311 	char *p;
312 	char **mem;
313 
314 	switch ((enum nss_lookup_type)(uintptr_t)cache_mdata) {
315 	case nss_lt_name:
316 		name = va_arg(ap, char *);
317 		break;
318 	case nss_lt_id:
319 		gid = va_arg(ap, gid_t);
320 		break;
321 	case nss_lt_all:
322 		break;
323 	default:
324 		/* should be unreachable */
325 		return (NS_UNAVAIL);
326 	}
327 
328 	grp = va_arg(ap, struct group *);
329 	orig_buf = va_arg(ap, char *);
330 	orig_buf_size = va_arg(ap, size_t);
331 	ret_errno = va_arg(ap, int *);
332 
333 	if (orig_buf_size + sizeof(struct group) + sizeof(char *) < buffer_size)
334 	{
335 		*ret_errno = ERANGE;
336 		return (NS_RETURN);
337 	} else if (buffer_size < sizeof(struct group) + sizeof(char *)) {
338 		/*
339 		 * nscd(8) sometimes returns buffer_size=1 for nonexistent
340 		 * entries.
341 		 */
342 		*ret_errno = 0;
343 		return (NS_NOTFOUND);
344 	}
345 
346 	memcpy(grp, buffer, sizeof(struct group));
347 	memcpy(&p, buffer + sizeof(struct group), sizeof(char *));
348 
349 	if (orig_buf_size + sizeof(struct group) + sizeof(char *) +
350 	    _ALIGN(p) - (size_t)p < buffer_size) {
351 		*ret_errno = ERANGE;
352 		return (NS_RETURN);
353 	}
354 
355 	orig_buf = (char *)_ALIGN(orig_buf);
356 	memcpy(orig_buf, buffer + sizeof(struct group) + sizeof(char *) +
357 	    _ALIGN(p) - (size_t)p,
358 	    buffer_size - sizeof(struct group) - sizeof(char *) -
359 	    _ALIGN(p) + (size_t)p);
360 	p = (char *)_ALIGN(p);
361 
362 	NS_APPLY_OFFSET(grp->gr_name, orig_buf, p, char *);
363 	NS_APPLY_OFFSET(grp->gr_passwd, orig_buf, p, char *);
364 	if (grp->gr_mem != NULL) {
365 		NS_APPLY_OFFSET(grp->gr_mem, orig_buf, p, char **);
366 
367 		for (mem = grp->gr_mem; *mem; ++mem)
368 			NS_APPLY_OFFSET(*mem, orig_buf, p, char *);
369 	}
370 
371 	if (retval != NULL)
372 		*((struct group **)retval) = grp;
373 
374 	return (NS_SUCCESS);
375 }
376 
377 NSS_MP_CACHE_HANDLING(group);
378 #endif /* NS_CACHING */
379 
380 #ifdef NS_CACHING
381 static const nss_cache_info setgrent_cache_info = NS_MP_CACHE_INFO_INITIALIZER(
382 	group, (void *)nss_lt_all,
383 	NULL, NULL);
384 #endif
385 
386 static const ns_dtab setgrent_dtab[] = {
387 	{ NSSRC_FILES, files_setgrent, (void *)SETGRENT },
388 #ifdef HESIOD
389 	{ NSSRC_DNS, dns_setgrent, (void *)SETGRENT },
390 #endif
391 #ifdef YP
392 	{ NSSRC_NIS, nis_setgrent, (void *)SETGRENT },
393 #endif
394 	{ NSSRC_COMPAT, compat_setgrent, (void *)SETGRENT },
395 #ifdef NS_CACHING
396 	NS_CACHE_CB(&setgrent_cache_info)
397 #endif
398 	{ NULL, NULL, NULL }
399 };
400 
401 #ifdef NS_CACHING
402 static const nss_cache_info endgrent_cache_info = NS_MP_CACHE_INFO_INITIALIZER(
403 	group, (void *)nss_lt_all,
404 	NULL, NULL);
405 #endif
406 
407 static const ns_dtab endgrent_dtab[] = {
408 	{ NSSRC_FILES, files_setgrent, (void *)ENDGRENT },
409 #ifdef HESIOD
410 	{ NSSRC_DNS, dns_setgrent, (void *)ENDGRENT },
411 #endif
412 #ifdef YP
413 	{ NSSRC_NIS, nis_setgrent, (void *)ENDGRENT },
414 #endif
415 	{ NSSRC_COMPAT, compat_setgrent, (void *)ENDGRENT },
416 #ifdef NS_CACHING
417 	NS_CACHE_CB(&endgrent_cache_info)
418 #endif
419 	{ NULL, NULL, NULL }
420 };
421 
422 #ifdef NS_CACHING
423 static const nss_cache_info getgrent_r_cache_info = NS_MP_CACHE_INFO_INITIALIZER(
424 	group, (void *)nss_lt_all,
425 	grp_marshal_func, grp_unmarshal_func);
426 #endif
427 
428 static const ns_dtab getgrent_r_dtab[] = {
429 	{ NSSRC_FILES, files_group, (void *)nss_lt_all },
430 #ifdef HESIOD
431 	{ NSSRC_DNS, dns_group, (void *)nss_lt_all },
432 #endif
433 #ifdef YP
434 	{ NSSRC_NIS, nis_group, (void *)nss_lt_all },
435 #endif
436 	{ NSSRC_COMPAT, compat_group, (void *)nss_lt_all },
437 #ifdef NS_CACHING
438 	NS_CACHE_CB(&getgrent_r_cache_info)
439 #endif
440 	{ NULL, NULL, NULL }
441 };
442 
443 static int
gr_addgid(gid_t gid,gid_t * groups,int maxgrp,int * grpcnt)444 gr_addgid(gid_t gid, gid_t *groups, int maxgrp, int *grpcnt)
445 {
446 	int     ret, dupc;
447 
448 	for (dupc = 1; dupc < MIN(maxgrp, *grpcnt); dupc++) {
449 		if (groups[dupc] == gid)
450 			return 1;
451 	}
452 
453 	ret = 1;
454 	if (*grpcnt < maxgrp)
455 		groups[*grpcnt] = gid;
456 	else
457 		ret = 0;
458 
459 	(*grpcnt)++;
460 
461 	return ret;
462 }
463 
464 static int
getgroupmembership_fallback(void * retval,void * mdata,va_list ap)465 getgroupmembership_fallback(void *retval, void *mdata, va_list ap)
466 {
467 	const ns_src src[] = {
468 		{ mdata, NS_SUCCESS },
469 		{ NULL, 0}
470 	};
471 	struct group	grp;
472 	struct group	*grp_p;
473 	char		*buf;
474 	size_t		bufsize;
475 	const char	*uname;
476 	gid_t		*groups;
477 	gid_t		agroup;
478 	int 		maxgrp, *grpcnt;
479 	int		i, rv, ret_errno;
480 
481 	/*
482 	 * As this is a fallback method, only provided src
483 	 * list will be respected during methods search.
484 	 */
485 	assert(src[0].name != NULL);
486 
487 	uname = va_arg(ap, const char *);
488 	agroup = va_arg(ap, gid_t);
489 	groups = va_arg(ap, gid_t *);
490 	maxgrp = va_arg(ap, int);
491 	grpcnt = va_arg(ap, int *);
492 
493 	rv = NS_UNAVAIL;
494 
495 	buf = malloc(GRP_STORAGE_INITIAL);
496 	if (buf == NULL)
497 		goto out;
498 
499 	bufsize = GRP_STORAGE_INITIAL;
500 
501 	gr_addgid(agroup, groups, maxgrp, grpcnt);
502 
503 	_nsdispatch(NULL, setgrent_dtab, NSDB_GROUP, "setgrent", src, 0);
504 	for (;;) {
505 		do {
506 			ret_errno = 0;
507 			grp_p = NULL;
508 			rv = _nsdispatch(&grp_p, getgrent_r_dtab, NSDB_GROUP,
509 			    "getgrent_r", src, &grp, buf, bufsize, &ret_errno);
510 
511 			if (grp_p == NULL && ret_errno == ERANGE) {
512 				free(buf);
513 				if ((bufsize << 1) > GRP_STORAGE_MAX) {
514 					buf = NULL;
515 					errno = ERANGE;
516 					goto out;
517 				}
518 
519 				bufsize <<= 1;
520 				buf = malloc(bufsize);
521 				if (buf == NULL) {
522 					goto out;
523 				}
524 			}
525 		} while (grp_p == NULL && ret_errno == ERANGE);
526 
527 		if (ret_errno != 0) {
528 			errno = ret_errno;
529 			goto out;
530 		}
531 
532 		if (grp_p == NULL)
533 			break;
534 
535 		for (i = 0; grp.gr_mem[i]; i++) {
536 			if (strcmp(grp.gr_mem[i], uname) == 0)
537 			    gr_addgid(grp.gr_gid, groups, maxgrp, grpcnt);
538 		}
539 	}
540 
541 	_nsdispatch(NULL, endgrent_dtab, NSDB_GROUP, "endgrent", src);
542 out:
543 	free(buf);
544 	return (rv);
545 }
546 
547 void
setgrent(void)548 setgrent(void)
549 {
550 	(void)_nsdispatch(NULL, setgrent_dtab, NSDB_GROUP, "setgrent", defaultsrc, 0);
551 }
552 
553 
554 int
setgroupent(int stayopen)555 setgroupent(int stayopen)
556 {
557 	(void)_nsdispatch(NULL, setgrent_dtab, NSDB_GROUP, "setgrent", defaultsrc,
558 	    stayopen);
559 	return (1);
560 }
561 
562 
563 void
endgrent(void)564 endgrent(void)
565 {
566 	(void)_nsdispatch(NULL, endgrent_dtab, NSDB_GROUP, "endgrent", defaultsrc);
567 }
568 
569 
570 int
getgrent_r(struct group * grp,char * buffer,size_t bufsize,struct group ** result)571 getgrent_r(struct group *grp, char *buffer, size_t bufsize,
572     struct group **result)
573 {
574 	int	rv, ret_errno;
575 
576 	ret_errno = 0;
577 	*result = NULL;
578 	rv = _nsdispatch(result, getgrent_r_dtab, NSDB_GROUP, "getgrent_r", defaultsrc,
579 	    grp, buffer, bufsize, &ret_errno);
580 	if (rv == NS_SUCCESS)
581 		return (0);
582 	else
583 		return (ret_errno);
584 }
585 
586 
587 int
getgrnam_r(const char * name,struct group * grp,char * buffer,size_t bufsize,struct group ** result)588 getgrnam_r(const char *name, struct group *grp, char *buffer, size_t bufsize,
589     struct group **result)
590 {
591 #ifdef NS_CACHING
592 	static const nss_cache_info cache_info =
593     		NS_COMMON_CACHE_INFO_INITIALIZER(
594 		group, (void *)nss_lt_name,
595 		grp_id_func, grp_marshal_func, grp_unmarshal_func);
596 #endif
597 
598 	static const ns_dtab dtab[] = {
599 		{ NSSRC_FILES, files_group, (void *)nss_lt_name },
600 #ifdef HESIOD
601 		{ NSSRC_DNS, dns_group, (void *)nss_lt_name },
602 #endif
603 #ifdef YP
604 		{ NSSRC_NIS, nis_group, (void *)nss_lt_name },
605 #endif
606 		{ NSSRC_COMPAT, compat_group, (void *)nss_lt_name },
607 #ifdef NS_CACHING
608 		NS_CACHE_CB(&cache_info)
609 #endif
610 		{ NULL, NULL, NULL }
611 	};
612 	int	rv, ret_errno;
613 
614 	ret_errno = 0;
615 	*result = NULL;
616 	rv = _nsdispatch(result, dtab, NSDB_GROUP, "getgrnam_r", defaultsrc,
617 	    name, grp, buffer, bufsize, &ret_errno);
618 	if (rv == NS_SUCCESS)
619 		return (0);
620 	else
621 		return (ret_errno);
622 }
623 
624 
625 int
getgrgid_r(gid_t gid,struct group * grp,char * buffer,size_t bufsize,struct group ** result)626 getgrgid_r(gid_t gid, struct group *grp, char *buffer, size_t bufsize,
627     struct group **result)
628 {
629 #ifdef NS_CACHING
630 	static const nss_cache_info cache_info =
631     		NS_COMMON_CACHE_INFO_INITIALIZER(
632 		group, (void *)nss_lt_id,
633 		grp_id_func, grp_marshal_func, grp_unmarshal_func);
634 #endif
635 
636 	static const ns_dtab dtab[] = {
637 		{ NSSRC_FILES, files_group, (void *)nss_lt_id },
638 #ifdef HESIOD
639 		{ NSSRC_DNS, dns_group, (void *)nss_lt_id },
640 #endif
641 #ifdef YP
642 		{ NSSRC_NIS, nis_group, (void *)nss_lt_id },
643 #endif
644 		{ NSSRC_COMPAT, compat_group, (void *)nss_lt_id },
645 #ifdef NS_CACHING
646 		NS_CACHE_CB(&cache_info)
647 #endif
648 		{ NULL, NULL, NULL }
649 	};
650 	int	rv, ret_errno;
651 
652 	ret_errno = 0;
653 	*result = NULL;
654 	rv = _nsdispatch(result, dtab, NSDB_GROUP, "getgrgid_r", defaultsrc,
655 	    gid, grp, buffer, bufsize, &ret_errno);
656 	if (rv == NS_SUCCESS)
657 		return (0);
658 	else
659 		return (ret_errno);
660 }
661 
662 
663 
664 int
__getgroupmembership(const char * uname,gid_t agroup,gid_t * groups,int maxgrp,int * grpcnt)665 __getgroupmembership(const char *uname, gid_t agroup, gid_t *groups,
666 	int maxgrp, int *grpcnt)
667 {
668 	static const ns_dtab dtab[] = {
669 		NS_FALLBACK_CB(getgroupmembership_fallback)
670 		{ NULL, NULL, NULL }
671 	};
672 
673 	assert(uname != NULL);
674 	/* groups may be NULL if just sizing when invoked with maxgrp = 0 */
675 	assert(grpcnt != NULL);
676 
677 	*grpcnt = 0;
678 	(void)_nsdispatch(NULL, dtab, NSDB_GROUP, "getgroupmembership",
679 	    defaultsrc, uname, agroup, groups, maxgrp, grpcnt);
680 
681 	/* too many groups found? */
682 	return (*grpcnt > maxgrp ? -1 : 0);
683 }
684 
685 
686 static struct group	 grp;
687 static char		*grp_storage;
688 static size_t		 grp_storage_size;
689 
690 static struct group *
getgr(int (* fn)(union key,struct group *,char *,size_t,struct group **),union key key)691 getgr(int (*fn)(union key, struct group *, char *, size_t, struct group **),
692     union key key)
693 {
694 	int		 rv;
695 	struct group	*res;
696 
697 	if (grp_storage == NULL) {
698 		grp_storage = malloc(GRP_STORAGE_INITIAL);
699 		if (grp_storage == NULL)
700 			return (NULL);
701 		grp_storage_size = GRP_STORAGE_INITIAL;
702 	}
703 	do {
704 		rv = fn(key, &grp, grp_storage, grp_storage_size, &res);
705 		if (res == NULL && rv == ERANGE) {
706 			free(grp_storage);
707 			if ((grp_storage_size << 1) > GRP_STORAGE_MAX) {
708 				grp_storage = NULL;
709 				errno = ERANGE;
710 				return (NULL);
711 			}
712 			grp_storage_size <<= 1;
713 			grp_storage = malloc(grp_storage_size);
714 			if (grp_storage == NULL)
715 				return (NULL);
716 		}
717 	} while (res == NULL && rv == ERANGE);
718 	if (rv != 0)
719 		errno = rv;
720 	return (res);
721 }
722 
723 
724 static int
wrap_getgrnam_r(union key key,struct group * grp,char * buffer,size_t bufsize,struct group ** res)725 wrap_getgrnam_r(union key key, struct group *grp, char *buffer, size_t bufsize,
726     struct group **res)
727 {
728 	return (getgrnam_r(key.name, grp, buffer, bufsize, res));
729 }
730 
731 
732 static int
wrap_getgrgid_r(union key key,struct group * grp,char * buffer,size_t bufsize,struct group ** res)733 wrap_getgrgid_r(union key key, struct group *grp, char *buffer, size_t bufsize,
734     struct group **res)
735 {
736 	return (getgrgid_r(key.gid, grp, buffer, bufsize, res));
737 }
738 
739 
740 static int
wrap_getgrent_r(union key key __unused,struct group * grp,char * buffer,size_t bufsize,struct group ** res)741 wrap_getgrent_r(union key key __unused, struct group *grp, char *buffer,
742     size_t bufsize, struct group **res)
743 {
744 	return (getgrent_r(grp, buffer, bufsize, res));
745 }
746 
747 
748 struct group *
getgrnam(const char * name)749 getgrnam(const char *name)
750 {
751 	union key key;
752 
753 	key.name = name;
754 	return (getgr(wrap_getgrnam_r, key));
755 }
756 
757 
758 struct group *
getgrgid(gid_t gid)759 getgrgid(gid_t gid)
760 {
761 	union key key;
762 
763 	key.gid = gid;
764 	return (getgr(wrap_getgrgid_r, key));
765 }
766 
767 
768 struct group *
getgrent(void)769 getgrent(void)
770 {
771 	union key key;
772 
773 	key.gid = 0; /* not used */
774 	return (getgr(wrap_getgrent_r, key));
775 }
776 
777 
778 static int
is_comment_line(const char * s,size_t n)779 is_comment_line(const char *s, size_t n)
780 {
781 	const char	*eom;
782 
783 	eom = &s[n];
784 
785 	for (; s < eom; s++)
786 		if (*s == '#' || !isspace((unsigned char)*s))
787 			break;
788 	return (*s == '#' || s == eom);
789 }
790 
791 
792 /*
793  * files backend
794  */
795 static void
files_endstate(void * p)796 files_endstate(void *p)
797 {
798 
799 	if (p == NULL)
800 		return;
801 	if (((struct files_state *)p)->fp != NULL)
802 		fclose(((struct files_state *)p)->fp);
803 	free(p);
804 }
805 
806 
807 static int
files_setgrent(void * retval,void * mdata,va_list ap)808 files_setgrent(void *retval, void *mdata, va_list ap)
809 {
810 	struct files_state *st;
811 	int		 rv, stayopen;
812 
813 	rv = files_getstate(&st);
814 	if (rv != 0)
815 		return (NS_UNAVAIL);
816 	switch ((enum constants)(uintptr_t)mdata) {
817 	case SETGRENT:
818 		stayopen = va_arg(ap, int);
819 		if (st->fp != NULL)
820 			rewind(st->fp);
821 		else if (stayopen)
822 			st->fp = fopen(_PATH_GROUP, "re");
823 		st->stayopen = stayopen;
824 		break;
825 	case ENDGRENT:
826 		if (st->fp != NULL) {
827 			fclose(st->fp);
828 			st->fp = NULL;
829 		}
830 		break;
831 	default:
832 		break;
833 	}
834 	return (NS_UNAVAIL);
835 }
836 
837 
838 static int
files_group(void * retval,void * mdata,va_list ap)839 files_group(void *retval, void *mdata, va_list ap)
840 {
841 	struct files_state	*st;
842 	enum nss_lookup_type	 how;
843 	const char		*name, *line;
844 	struct group		*grp;
845 	gid_t			 gid;
846 	char			*buffer;
847 	size_t			 bufsize, linesize;
848 	off_t			 pos;
849 	int			 fresh, rv, stayopen, *errnop;
850 
851 	fresh = 0;
852 	name = NULL;
853 	gid = (gid_t)-1;
854 	how = (enum nss_lookup_type)(uintptr_t)mdata;
855 	switch (how) {
856 	case nss_lt_name:
857 		name = va_arg(ap, const char *);
858 		break;
859 	case nss_lt_id:
860 		gid = va_arg(ap, gid_t);
861 		break;
862 	case nss_lt_all:
863 		break;
864 	default:
865 		return (NS_NOTFOUND);
866 	}
867 	grp = va_arg(ap, struct group *);
868 	buffer = va_arg(ap, char *);
869 	bufsize = va_arg(ap, size_t);
870 	errnop = va_arg(ap, int *);
871 	*errnop = files_getstate(&st);
872 	if (*errnop != 0)
873 		return (NS_UNAVAIL);
874 	if (st->fp == NULL) {
875 		st->fp = fopen(_PATH_GROUP, "re");
876 		if (st->fp == NULL) {
877 			*errnop = errno;
878 			return (NS_UNAVAIL);
879 		}
880 		fresh = 1;
881 	}
882 	stayopen = (how == nss_lt_all || !fresh) ? 1 : st->stayopen;
883 	if (stayopen)
884 		pos = ftello(st->fp);
885 	if (how != nss_lt_all && !fresh)
886 		rewind(st->fp);
887 	rv = NS_NOTFOUND;
888 	while ((line = fgetln(st->fp, &linesize)) != NULL) {
889 		if (line[linesize-1] == '\n')
890 			linesize--;
891 		rv = __gr_match_entry(line, linesize, how, name, gid);
892 		if (rv != NS_SUCCESS)
893 			continue;
894 		/* We need room at least for the line, a string NUL
895 		 * terminator, alignment padding, and one (char *)
896 		 * pointer for the member list terminator.
897 		 */
898 		if (bufsize <= linesize + _ALIGNBYTES + sizeof(char *)) {
899 			*errnop = ERANGE;
900 			rv = NS_RETURN;
901 			break;
902 		}
903 		memcpy(buffer, line, linesize);
904 		buffer[linesize] = '\0';
905 		rv = __gr_parse_entry(buffer, linesize, grp,
906 		    &buffer[linesize + 1], bufsize - linesize - 1, errnop);
907 		if (rv & NS_TERMINATE)
908 			break;
909 		if (how == nss_lt_all)
910 			pos = ftello(st->fp);
911 	}
912 	if (st->fp != NULL && !stayopen) {
913 		fclose(st->fp);
914 		st->fp = NULL;
915 	}
916 	if (st->fp != NULL && how != nss_lt_all)
917 		fseeko(st->fp, pos, SEEK_SET);
918 	if (rv == NS_SUCCESS && retval != NULL)
919 		*(struct group **)retval = grp;
920 	else if (rv == NS_RETURN && *errnop == ERANGE && st->fp != NULL)
921 		fseeko(st->fp, pos, SEEK_SET);
922 	return (rv);
923 }
924 
925 
926 #ifdef HESIOD
927 /*
928  * dns backend
929  */
930 static void
dns_endstate(void * p)931 dns_endstate(void *p)
932 {
933 
934 	free(p);
935 }
936 
937 
938 static int
dns_setgrent(void * retval,void * cb_data,va_list ap)939 dns_setgrent(void *retval, void *cb_data, va_list ap)
940 {
941 	struct dns_state	*st;
942 	int			 rv;
943 
944 	rv = dns_getstate(&st);
945 	if (rv != 0)
946 		return (NS_UNAVAIL);
947 	st->counter = 0;
948 	return (NS_UNAVAIL);
949 }
950 
951 
952 static int
dns_group(void * retval,void * mdata,va_list ap)953 dns_group(void *retval, void *mdata, va_list ap)
954 {
955 	char			 buf[HESIOD_NAME_MAX];
956 	struct dns_state	*st;
957 	struct group		*grp;
958 	const char		*name, *label;
959 	void			*ctx;
960 	char			*buffer, **hes;
961 	size_t			 bufsize, adjsize, linesize;
962 	gid_t			 gid;
963 	enum nss_lookup_type	 how;
964 	int			 rv, *errnop;
965 
966 	ctx = NULL;
967 	hes = NULL;
968 	name = NULL;
969 	gid = (gid_t)-1;
970 	how = (enum nss_lookup_type)(uintptr_t)mdata;
971 	switch (how) {
972 	case nss_lt_name:
973 		name = va_arg(ap, const char *);
974 		break;
975 	case nss_lt_id:
976 		gid = va_arg(ap, gid_t);
977 		break;
978 	case nss_lt_all:
979 		break;
980 	}
981 	grp     = va_arg(ap, struct group *);
982 	buffer  = va_arg(ap, char *);
983 	bufsize = va_arg(ap, size_t);
984 	errnop  = va_arg(ap, int *);
985 	*errnop = dns_getstate(&st);
986 	if (*errnop != 0)
987 		return (NS_UNAVAIL);
988 	if (hesiod_init(&ctx) != 0) {
989 		*errnop = errno;
990 		rv = NS_UNAVAIL;
991 		goto fin;
992 	}
993 	do {
994 		rv = NS_NOTFOUND;
995 		switch (how) {
996 		case nss_lt_name:
997 			label = name;
998 			break;
999 		case nss_lt_id:
1000 			if (snprintf(buf, sizeof(buf), "%lu",
1001 			    (unsigned long)gid) >= sizeof(buf))
1002 				goto fin;
1003 			label = buf;
1004 			break;
1005 		case nss_lt_all:
1006 			if (st->counter < 0)
1007 				goto fin;
1008 			if (snprintf(buf, sizeof(buf), "group-%ld",
1009 			    st->counter++) >= sizeof(buf))
1010 				goto fin;
1011 			label = buf;
1012 			break;
1013 		}
1014 		hes = hesiod_resolve(ctx, label,
1015 		    how == nss_lt_id ? "gid" : "group");
1016 		if ((how == nss_lt_id && hes == NULL &&
1017 		    (hes = hesiod_resolve(ctx, buf, "group")) == NULL) ||
1018 		    hes == NULL) {
1019 			if (how == nss_lt_all)
1020 				st->counter = -1;
1021 			if (errno != ENOENT)
1022 				*errnop = errno;
1023 			goto fin;
1024 		}
1025 		rv = __gr_match_entry(hes[0], strlen(hes[0]), how, name, gid);
1026 		if (rv != NS_SUCCESS) {
1027 			hesiod_free_list(ctx, hes);
1028 			hes = NULL;
1029 			continue;
1030 		}
1031 		/* We need room at least for the line, a string NUL
1032 		 * terminator, alignment padding, and one (char *)
1033 		 * pointer for the member list terminator.
1034 		 */
1035 		adjsize = bufsize - _ALIGNBYTES - sizeof(char *);
1036 		linesize = strlcpy(buffer, hes[0], adjsize);
1037 		if (linesize >= adjsize) {
1038 			*errnop = ERANGE;
1039 			rv = NS_RETURN;
1040 			goto fin;
1041 		}
1042 		hesiod_free_list(ctx, hes);
1043 		hes = NULL;
1044 		rv = __gr_parse_entry(buffer, linesize, grp,
1045 		    &buffer[linesize + 1], bufsize - linesize - 1, errnop);
1046 	} while (how == nss_lt_all && !(rv & NS_TERMINATE));
1047 fin:
1048 	if (hes != NULL)
1049 		hesiod_free_list(ctx, hes);
1050 	if (ctx != NULL)
1051 		hesiod_end(ctx);
1052 	if (rv == NS_SUCCESS && retval != NULL)
1053 		*(struct group **)retval = grp;
1054 	return (rv);
1055 }
1056 #endif /* HESIOD */
1057 
1058 
1059 #ifdef YP
1060 /*
1061  * nis backend
1062  */
1063 static void
nis_endstate(void * p)1064 nis_endstate(void *p)
1065 {
1066 
1067 	if (p == NULL)
1068 		return;
1069 	free(((struct nis_state *)p)->key);
1070 	free(p);
1071 }
1072 
1073 
1074 static int
nis_setgrent(void * retval,void * cb_data,va_list ap)1075 nis_setgrent(void *retval, void *cb_data, va_list ap)
1076 {
1077 	struct nis_state	*st;
1078 	int			 rv;
1079 
1080 	rv = nis_getstate(&st);
1081 	if (rv != 0)
1082 		return (NS_UNAVAIL);
1083 	st->done = 0;
1084 	free(st->key);
1085 	st->key = NULL;
1086 	return (NS_UNAVAIL);
1087 }
1088 
1089 
1090 static int
nis_group(void * retval,void * mdata,va_list ap)1091 nis_group(void *retval, void *mdata, va_list ap)
1092 {
1093 	char		 *map;
1094 	struct nis_state *st;
1095 	struct group	*grp;
1096 	const char	*name;
1097 	char		*buffer, *key, *result;
1098 	size_t		 bufsize;
1099 	gid_t		 gid;
1100 	enum nss_lookup_type how;
1101 	int		*errnop, keylen, resultlen, rv;
1102 
1103 	name = NULL;
1104 	gid = (gid_t)-1;
1105 	how = (enum nss_lookup_type)(uintptr_t)mdata;
1106 	switch (how) {
1107 	case nss_lt_name:
1108 		name = va_arg(ap, const char *);
1109 		map = "group.byname";
1110 		break;
1111 	case nss_lt_id:
1112 		gid = va_arg(ap, gid_t);
1113 		map = "group.bygid";
1114 		break;
1115 	case nss_lt_all:
1116 		map = "group.byname";
1117 		break;
1118 	}
1119 	grp     = va_arg(ap, struct group *);
1120 	buffer  = va_arg(ap, char *);
1121 	bufsize = va_arg(ap, size_t);
1122 	errnop  = va_arg(ap, int *);
1123 	*errnop = nis_getstate(&st);
1124 	if (*errnop != 0)
1125 		return (NS_UNAVAIL);
1126 	if (st->domain[0] == '\0') {
1127 		if (getdomainname(st->domain, sizeof(st->domain)) != 0) {
1128 			*errnop = errno;
1129 			return (NS_UNAVAIL);
1130 		}
1131 	}
1132 	result = NULL;
1133 	do {
1134 		rv = NS_NOTFOUND;
1135 		switch (how) {
1136 		case nss_lt_name:
1137 			if (strlcpy(buffer, name, bufsize) >= bufsize)
1138 				goto erange;
1139 			break;
1140 		case nss_lt_id:
1141 			if (snprintf(buffer, bufsize, "%lu",
1142 			    (unsigned long)gid) >= bufsize)
1143 				goto erange;
1144 			break;
1145 		case nss_lt_all:
1146 			if (st->done)
1147 				goto fin;
1148 			break;
1149 		}
1150 		result = NULL;
1151 		if (how == nss_lt_all) {
1152 			if (st->key == NULL)
1153 				rv = yp_first(st->domain, map, &st->key,
1154 				    &st->keylen, &result, &resultlen);
1155 			else {
1156 				key = st->key;
1157 				keylen = st->keylen;
1158 				st->key = NULL;
1159 				rv = yp_next(st->domain, map, key, keylen,
1160 				    &st->key, &st->keylen, &result,
1161 				    &resultlen);
1162 				free(key);
1163 			}
1164 			if (rv != 0) {
1165 				free(result);
1166 				free(st->key);
1167 				st->key = NULL;
1168 				if (rv == YPERR_NOMORE) {
1169 					st->done = 1;
1170 					rv = NS_NOTFOUND;
1171 				} else
1172 					rv = NS_UNAVAIL;
1173 				goto fin;
1174 			}
1175 		} else {
1176 			rv = yp_match(st->domain, map, buffer, strlen(buffer),
1177 			    &result, &resultlen);
1178 			if (rv == YPERR_KEY) {
1179 				rv = NS_NOTFOUND;
1180 				continue;
1181 			} else if (rv != 0) {
1182 				free(result);
1183 				rv = NS_UNAVAIL;
1184 				continue;
1185 			}
1186 		}
1187 		/* We need room at least for the line, a string NUL
1188 		 * terminator, alignment padding, and one (char *)
1189 		 * pointer for the member list terminator.
1190 		 */
1191 		if (resultlen >= bufsize - _ALIGNBYTES - sizeof(char *)) {
1192 			free(result);
1193 			goto erange;
1194 		}
1195 		memcpy(buffer, result, resultlen);
1196 		buffer[resultlen] = '\0';
1197 		free(result);
1198 		rv = __gr_match_entry(buffer, resultlen, how, name, gid);
1199 		if (rv == NS_SUCCESS)
1200 			rv = __gr_parse_entry(buffer, resultlen, grp,
1201 			    &buffer[resultlen+1], bufsize - resultlen - 1,
1202 			    errnop);
1203 	} while (how == nss_lt_all && !(rv & NS_TERMINATE));
1204 fin:
1205 	if (rv == NS_SUCCESS && retval != NULL)
1206 		*(struct group **)retval = grp;
1207 	return (rv);
1208 erange:
1209 	*errnop = ERANGE;
1210 	return (NS_RETURN);
1211 }
1212 #endif /* YP */
1213 
1214 
1215 
1216 /*
1217  * compat backend
1218  */
1219 static void
compat_endstate(void * p)1220 compat_endstate(void *p)
1221 {
1222 	struct compat_state *st;
1223 
1224 	if (p == NULL)
1225 		return;
1226 	st = (struct compat_state *)p;
1227 	free(st->name);
1228 	if (st->fp != NULL)
1229 		fclose(st->fp);
1230 	free(p);
1231 }
1232 
1233 
1234 static int
compat_setgrent(void * retval,void * mdata,va_list ap)1235 compat_setgrent(void *retval, void *mdata, va_list ap)
1236 {
1237 	static const ns_src compatsrc[] = {
1238 #ifdef YP
1239 		{ NSSRC_NIS, NS_SUCCESS },
1240 #endif
1241 		{ NULL, 0 }
1242 	};
1243 	ns_dtab dtab[] = {
1244 #ifdef HESIOD
1245 		{ NSSRC_DNS, dns_setgrent, NULL },
1246 #endif
1247 #ifdef YP
1248 		{ NSSRC_NIS, nis_setgrent, NULL },
1249 #endif
1250 		{ NULL, NULL, NULL }
1251 	};
1252 	struct compat_state *st;
1253 	int		 rv, stayopen;
1254 
1255 #define set_setent(x, y) do {	 				\
1256 	int i;							\
1257 	for (i = 0; i < (int)(nitems(x) - 1); i++)		\
1258 		x[i].mdata = (void *)y;				\
1259 } while (0)
1260 
1261 	rv = compat_getstate(&st);
1262 	if (rv != 0)
1263 		return (NS_UNAVAIL);
1264 	switch ((enum constants)(uintptr_t)mdata) {
1265 	case SETGRENT:
1266 		stayopen = va_arg(ap, int);
1267 		if (st->fp != NULL)
1268 			rewind(st->fp);
1269 		else if (stayopen)
1270 			st->fp = fopen(_PATH_GROUP, "re");
1271 		st->stayopen = stayopen;
1272 		set_setent(dtab, mdata);
1273 		(void)_nsdispatch(NULL, dtab, NSDB_GROUP_COMPAT, "setgrent",
1274 		    compatsrc, 0);
1275 		break;
1276 	case ENDGRENT:
1277 		if (st->fp != NULL) {
1278 			fclose(st->fp);
1279 			st->fp = NULL;
1280 		}
1281 		set_setent(dtab, mdata);
1282 		(void)_nsdispatch(NULL, dtab, NSDB_GROUP_COMPAT, "endgrent",
1283 		    compatsrc, 0);
1284 		break;
1285 	default:
1286 		break;
1287 	}
1288 	st->compat = COMPAT_MODE_OFF;
1289 	free(st->name);
1290 	st->name = NULL;
1291 	return (NS_UNAVAIL);
1292 #undef set_setent
1293 }
1294 
1295 
1296 static int
compat_group(void * retval,void * mdata,va_list ap)1297 compat_group(void *retval, void *mdata, va_list ap)
1298 {
1299 	static const ns_src compatsrc[] = {
1300 #ifdef YP
1301 		{ NSSRC_NIS, NS_SUCCESS },
1302 #endif
1303 		{ NULL, 0 }
1304 	};
1305 	ns_dtab dtab[] = {
1306 #ifdef YP
1307 		{ NSSRC_NIS, nis_group, NULL },
1308 #endif
1309 #ifdef HESIOD
1310 		{ NSSRC_DNS, dns_group, NULL },
1311 #endif
1312 		{ NULL, NULL, NULL }
1313 	};
1314 	struct compat_state	*st;
1315 	enum nss_lookup_type	 how;
1316 	const char		*name, *line;
1317 	struct group		*grp;
1318 	gid_t			 gid;
1319 	char			*buffer, *p;
1320 	void			*discard;
1321 	size_t			 bufsize, linesize;
1322 	off_t			 pos;
1323 	int			 fresh, rv, stayopen, *errnop;
1324 
1325 #define set_lookup_type(x, y) do { 				\
1326 	int i;							\
1327 	for (i = 0; i < (int)(nitems(x) - 1); i++)		\
1328 		x[i].mdata = (void *)y;				\
1329 } while (0)
1330 
1331 	fresh = 0;
1332 	name = NULL;
1333 	gid = (gid_t)-1;
1334 	how = (enum nss_lookup_type)(uintptr_t)mdata;
1335 	switch (how) {
1336 	case nss_lt_name:
1337 		name = va_arg(ap, const char *);
1338 		break;
1339 	case nss_lt_id:
1340 		gid = va_arg(ap, gid_t);
1341 		break;
1342 	case nss_lt_all:
1343 		break;
1344 	default:
1345 		return (NS_NOTFOUND);
1346 	}
1347 	grp = va_arg(ap, struct group *);
1348 	buffer = va_arg(ap, char *);
1349 	bufsize = va_arg(ap, size_t);
1350 	errnop = va_arg(ap, int *);
1351 	*errnop = compat_getstate(&st);
1352 	if (*errnop != 0)
1353 		return (NS_UNAVAIL);
1354 	if (st->fp == NULL) {
1355 		st->fp = fopen(_PATH_GROUP, "re");
1356 		if (st->fp == NULL) {
1357 			*errnop = errno;
1358 			rv = NS_UNAVAIL;
1359 			goto fin;
1360 		}
1361 		fresh = 1;
1362 	}
1363 	stayopen = (how == nss_lt_all || !fresh) ? 1 : st->stayopen;
1364 	if (stayopen)
1365 		pos = ftello(st->fp);
1366 	if (how != nss_lt_all && !fresh)
1367 		rewind(st->fp);
1368 docompat:
1369 	switch (st->compat) {
1370 	case COMPAT_MODE_ALL:
1371 		set_lookup_type(dtab, how);
1372 		switch (how) {
1373 		case nss_lt_all:
1374 			rv = _nsdispatch(&discard, dtab, NSDB_GROUP_COMPAT,
1375 			    "getgrent_r", compatsrc, grp, buffer, bufsize,
1376 			    errnop);
1377 			break;
1378 		case nss_lt_id:
1379 			rv = _nsdispatch(&discard, dtab, NSDB_GROUP_COMPAT,
1380 			    "getgrgid_r", compatsrc, gid, grp, buffer, bufsize,
1381 			    errnop);
1382 			break;
1383 		case nss_lt_name:
1384 			rv = _nsdispatch(&discard, dtab, NSDB_GROUP_COMPAT,
1385 			    "getgrnam_r", compatsrc, name, grp, buffer,
1386 			    bufsize, errnop);
1387 			break;
1388 		}
1389 		if (rv & NS_TERMINATE)
1390 			goto fin;
1391 		st->compat = COMPAT_MODE_OFF;
1392 		break;
1393 	case COMPAT_MODE_NAME:
1394 		set_lookup_type(dtab, nss_lt_name);
1395 		rv = _nsdispatch(&discard, dtab, NSDB_GROUP_COMPAT,
1396 		    "getgrnam_r", compatsrc, st->name, grp, buffer, bufsize,
1397 		    errnop);
1398 		switch (rv) {
1399 		case NS_SUCCESS:
1400 			switch (how) {
1401 			case nss_lt_name:
1402 				if (strcmp(name, grp->gr_name) != 0)
1403 					rv = NS_NOTFOUND;
1404 				break;
1405 			case nss_lt_id:
1406 				if (gid != grp->gr_gid)
1407 					rv = NS_NOTFOUND;
1408 				break;
1409 			default:
1410 				break;
1411 			}
1412 			break;
1413 		case NS_RETURN:
1414 			goto fin;
1415 		default:
1416 			break;
1417 		}
1418 		free(st->name);
1419 		st->name = NULL;
1420 		st->compat = COMPAT_MODE_OFF;
1421 		if (rv == NS_SUCCESS)
1422 			goto fin;
1423 		break;
1424 	default:
1425 		break;
1426 	}
1427 	rv = NS_NOTFOUND;
1428 	while ((line = fgetln(st->fp, &linesize)) != NULL) {
1429 		if (line[linesize-1] == '\n')
1430 			linesize--;
1431 		if (linesize > 2 && line[0] == '+') {
1432 			p = memchr(&line[1], ':', linesize);
1433 			if (p == NULL || p == &line[1])
1434 				st->compat = COMPAT_MODE_ALL;
1435 			else {
1436 				st->name = malloc(p - line);
1437 				if (st->name == NULL) {
1438 					syslog(LOG_ERR,
1439 					 "getgrent memory allocation failure");
1440 					*errnop = ENOMEM;
1441 					rv = NS_UNAVAIL;
1442 					break;
1443 				}
1444 				memcpy(st->name, &line[1], p - line - 1);
1445 				st->name[p - line - 1] = '\0';
1446 				st->compat = COMPAT_MODE_NAME;
1447 			}
1448 			goto docompat;
1449 		}
1450 		rv = __gr_match_entry(line, linesize, how, name, gid);
1451 		if (rv != NS_SUCCESS)
1452 			continue;
1453 		/* We need room at least for the line, a string NUL
1454 		 * terminator, alignment padding, and one (char *)
1455 		 * pointer for the member list terminator.
1456 		 */
1457 		if (bufsize <= linesize + _ALIGNBYTES + sizeof(char *)) {
1458 			*errnop = ERANGE;
1459 			rv = NS_RETURN;
1460 			break;
1461 		}
1462 		memcpy(buffer, line, linesize);
1463 		buffer[linesize] = '\0';
1464 		rv = __gr_parse_entry(buffer, linesize, grp,
1465 		    &buffer[linesize + 1], bufsize - linesize - 1, errnop);
1466 		if (rv & NS_TERMINATE)
1467 			break;
1468 		if (how == nss_lt_all)
1469 			pos = ftello(st->fp);
1470 	}
1471 fin:
1472 	if (st->fp != NULL && !stayopen) {
1473 		fclose(st->fp);
1474 		st->fp = NULL;
1475 	}
1476 	if (st->fp != NULL && how != nss_lt_all)
1477 		fseeko(st->fp, pos, SEEK_SET);
1478 	if (rv == NS_SUCCESS && retval != NULL)
1479 		*(struct group **)retval = grp;
1480 	else if (rv == NS_RETURN && *errnop == ERANGE && st->fp != NULL)
1481 		fseeko(st->fp, pos, SEEK_SET);
1482 	return (rv);
1483 #undef set_lookup_type
1484 }
1485 
1486 
1487 /*
1488  * common group line matching and parsing
1489  */
1490 int
__gr_match_entry(const char * line,size_t linesize,enum nss_lookup_type how,const char * name,gid_t gid)1491 __gr_match_entry(const char *line, size_t linesize, enum nss_lookup_type how,
1492     const char *name, gid_t gid)
1493 {
1494 	size_t		 namesize;
1495 	const char	*p, *eol;
1496 	char		*q;
1497 	unsigned long	 n;
1498 	int		 i, needed;
1499 
1500 	if (linesize == 0 || is_comment_line(line, linesize))
1501 		return (NS_NOTFOUND);
1502 	switch (how) {
1503 	case nss_lt_name:	needed = 1; break;
1504 	case nss_lt_id:		needed = 2; break;
1505 	default:		needed = 2; break;
1506 	}
1507 	eol = &line[linesize];
1508 	for (p = line, i = 0; i < needed && p < eol; p++)
1509 		if (*p == ':')
1510 			i++;
1511 	if (i < needed)
1512 		return (NS_NOTFOUND);
1513 	switch (how) {
1514 	case nss_lt_name:
1515 		namesize = strlen(name);
1516 		if (namesize + 1 == (size_t)(p - line) &&
1517 		    memcmp(line, name, namesize) == 0)
1518 			return (NS_SUCCESS);
1519 		break;
1520 	case nss_lt_id:
1521 		n = strtoul(p, &q, 10);
1522 		if (q < eol && *q == ':' && gid == (gid_t)n)
1523 			return (NS_SUCCESS);
1524 		break;
1525 	case nss_lt_all:
1526 		return (NS_SUCCESS);
1527 	default:
1528 		break;
1529 	}
1530 	return (NS_NOTFOUND);
1531 }
1532 
1533 
1534 int
__gr_parse_entry(char * line,size_t linesize,struct group * grp,char * membuf,size_t membufsize,int * errnop)1535 __gr_parse_entry(char *line, size_t linesize, struct group *grp, char *membuf,
1536     size_t membufsize, int *errnop)
1537 {
1538 	char	       *s_gid, *s_mem, *p, **members;
1539 	unsigned long	n;
1540 	int		maxmembers;
1541 
1542 	memset(grp, 0, sizeof(*grp));
1543 	members = (char **)_ALIGN(membuf);
1544 	membufsize -= (char *)members - membuf;
1545 	maxmembers = membufsize / sizeof(*members);
1546 	if (maxmembers <= 0 ||
1547 	    (grp->gr_name = strsep(&line, ":")) == NULL ||
1548 	    grp->gr_name[0] == '\0' ||
1549 	    (grp->gr_passwd = strsep(&line, ":")) == NULL ||
1550 	    (s_gid = strsep(&line, ":")) == NULL ||
1551 	    s_gid[0] == '\0')
1552 		return (NS_NOTFOUND);
1553 	s_mem = line;
1554 	n = strtoul(s_gid, &s_gid, 10);
1555 	if (s_gid[0] != '\0')
1556 		return (NS_NOTFOUND);
1557 	grp->gr_gid = (gid_t)n;
1558 	grp->gr_mem = members;
1559 	while (maxmembers > 1 && s_mem != NULL) {
1560 		p = strsep(&s_mem, ",");
1561 		if (p != NULL && *p != '\0') {
1562 			*members++ = p;
1563 			maxmembers--;
1564 		}
1565 	}
1566 	*members = NULL;
1567 	if (s_mem == NULL)
1568 		return (NS_SUCCESS);
1569 	else {
1570 		*errnop = ERANGE;
1571 		return (NS_RETURN);
1572 	}
1573 }
1574 
1575 
1576