getnetgrent.c revision 1.24 1 /* $NetBSD: getnetgrent.c,v 1.24 1999/09/16 11:44:59 lukem Exp $ */
2
3 /*
4 * Copyright (c) 1994 Christos Zoulas
5 * 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. All advertising materials mentioning features or use of this software
16 * must display the following acknowledgement:
17 * This product includes software developed by Christos Zoulas.
18 * 4. The name of the author may not be used to endorse or promote products
19 * derived from this software without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
22 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
23 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
25 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34 #include <sys/cdefs.h>
35 #if defined(LIBC_SCCS) && !defined(lint)
36 __RCSID("$NetBSD: getnetgrent.c,v 1.24 1999/09/16 11:44:59 lukem Exp $");
37 #endif /* LIBC_SCCS and not lint */
38
39 #include "namespace.h"
40 #include <sys/types.h>
41
42 #include <assert.h>
43 #include <ctype.h>
44 #include <db.h>
45 #include <err.h>
46 #include <fcntl.h>
47 #define _NETGROUP_PRIVATE
48 #include <netgroup.h>
49 #include <nsswitch.h>
50 #include <stdio.h>
51 #include <stdlib.h>
52 #include <string.h>
53 #include <stringlist.h>
54
55 #ifdef YP
56 #include <rpc/rpc.h>
57 #include <rpcsvc/ypclnt.h>
58 #include <rpcsvc/yp_prot.h>
59 #endif
60
61 #ifdef __STDC__
62 #include <stdarg.h>
63 #else
64 #include <varargs.h>
65 #endif
66
67 #ifdef __weak_alias
68 __weak_alias(endnetgrent,_endnetgrent);
69 __weak_alias(getnetgrent,_getnetgrent);
70 __weak_alias(innetgr,_innetgr);
71 __weak_alias(setnetgrent,_setnetgrent);
72 #endif
73
74 #define _NG_STAR(s) (((s) == NULL || *(s) == '\0') ? _ngstar : s)
75 #define _NG_EMPTY(s) ((s) == NULL ? "" : s)
76 #define _NG_ISSPACE(p) (isspace((unsigned char) (p)) || (p) == '\n')
77
78 static const char _ngstar[] = "*";
79 static const char _ngoomem[] = "netgroup: %m";
80 static struct netgroup *_nghead = (struct netgroup *)NULL;
81 static struct netgroup *_nglist = (struct netgroup *)NULL;
82 static DB *_ng_db;
83
84 static int getstring __P((char **, int, __aconst char **));
85 static struct netgroup *getnetgroup __P((char **));
86 static int lookup __P((char *, char **, int));
87 static void addgroup __P((StringList *, char *));
88 static int in_check __P((const char *, const char *,
89 const char *, struct netgroup *));
90 static int in_find __P((StringList *, char *, const char *,
91 const char *, const char *));
92 static char *in_lookup1 __P((const char *, const char *, int));
93 static int in_lookup __P((const char *, const char *,
94 const char *, int));
95
96 static const ns_src default_files_nis[] = {
97 { NSSRC_FILES, NS_SUCCESS | NS_NOTFOUND },
98 #ifdef YP
99 { NSSRC_NIS, NS_SUCCESS },
100 #endif
101 { 0 }
102 };
103
104 /*
105 * getstring(): Get a string delimited by the character, skipping leading and
106 * trailing blanks and advancing the pointer
107 */
108 static int
109 getstring(pp, del, str)
110 char **pp;
111 int del;
112 char __aconst **str;
113 {
114 size_t len;
115 char *sp, *ep, *dp;
116
117 _DIAGASSERT(pp != NULL);
118 _DIAGASSERT(str != NULL);
119
120 /* skip leading blanks */
121 for (sp = *pp; *sp && _NG_ISSPACE(*sp); sp++)
122 continue;
123
124 /* accumulate till delimiter or space */
125 for (ep = sp; *ep && *ep != del && !_NG_ISSPACE(*ep); ep++)
126 continue;
127
128 /* hunt for the delimiter */
129 for (dp = ep; *dp && *dp != del && _NG_ISSPACE(*dp); dp++)
130 continue;
131
132 if (*dp != del) {
133 *str = NULL;
134 return 0;
135 }
136
137 *pp = ++dp;
138
139 len = (ep - sp) + 1;
140 if (len > 1) {
141 dp = malloc(len);
142 if (dp == NULL)
143 err(1, _ngoomem);
144 memcpy(dp, sp, len);
145 dp[len - 1] = '\0';
146 } else
147 dp = NULL;
148
149 *str = dp;
150 return 1;
151 }
152
153
154 /*
155 * getnetgroup(): Parse a netgroup, and advance the pointer
156 */
157 static struct netgroup *
158 getnetgroup(pp)
159 char **pp;
160 {
161 struct netgroup *ng;
162
163 _DIAGASSERT(pp != NULL);
164 _DIAGASSERT(*pp != NULL);
165
166 ng = malloc(sizeof(struct netgroup));
167 if (ng == NULL)
168 err(1, _ngoomem);
169
170 (*pp)++; /* skip '(' */
171 if (!getstring(pp, ',', &ng->ng_host))
172 goto badhost;
173
174 if (!getstring(pp, ',', &ng->ng_user))
175 goto baduser;
176
177 if (!getstring(pp, ')', &ng->ng_domain))
178 goto baddomain;
179
180 #ifdef DEBUG_NG
181 {
182 char buf[1024];
183 (void) fprintf(stderr, "netgroup %s\n",
184 _ng_print(buf, sizeof(buf), ng));
185 }
186 #endif
187 return ng;
188
189 baddomain:
190 if (ng->ng_user)
191 free((char *)ng->ng_user);
192 baduser:
193 if (ng->ng_host)
194 free((char *)ng->ng_host);
195 badhost:
196 free(ng);
197 return NULL;
198 }
199
200
201 static int _local_lookup __P((void *, void *, va_list));
202
203 /*ARGSUSED*/
204 static int
205 _local_lookup(rv, cb_data, ap)
206 void *rv;
207 void *cb_data;
208 va_list ap;
209 {
210 char *name = va_arg(ap, char *);
211 char **line = va_arg(ap, char **);
212 int bywhat = va_arg(ap, int);
213
214 DBT key, data;
215 size_t len;
216 char *ks;
217 int r;
218
219 if (_ng_db == NULL)
220 return NS_UNAVAIL;
221
222 len = strlen(name) + 2;
223 ks = malloc(len);
224 if (ks == NULL)
225 err(1, _ngoomem);
226
227 ks[0] = bywhat;
228 memcpy(&ks[1], name, len - 1);
229
230 key.data = (u_char *) ks;
231 key.size = len;
232
233 r = (_ng_db->get) (_ng_db, &key, &data, 0);
234 free(ks);
235 switch (r) {
236 case 0:
237 break;
238 case 1:
239 return NS_NOTFOUND;
240 case -1:
241 /* XXX: call endnetgrent() here ? */
242 return NS_UNAVAIL;
243 }
244
245 *line = strdup(data.data);
246 if (*line == NULL)
247 return NS_UNAVAIL;
248 return NS_SUCCESS;
249 }
250
251 #ifdef YP
252 static int _nis_lookup __P((void *, void *, va_list));
253
254 /*ARGSUSED*/
255 static int
256 _nis_lookup(rv, cb_data, ap)
257 void *rv;
258 void *cb_data;
259 va_list ap;
260 {
261 char *name = va_arg(ap, char *);
262 char **line = va_arg(ap, char **);
263 int bywhat = va_arg(ap, int);
264
265 static char *__ypdomain;
266 int i;
267 char *map = NULL;
268
269 if(__ypdomain == NULL) {
270 switch (yp_get_default_domain(&__ypdomain)) {
271 case 0:
272 break;
273 case YPERR_RESRC:
274 return NS_TRYAGAIN;
275 default:
276 return NS_UNAVAIL;
277 }
278 }
279
280 switch (bywhat) {
281 case _NG_KEYBYNAME:
282 map = "netgroup";
283 break;
284
285 case _NG_KEYBYUSER:
286 map = "netgroup.byuser";
287 break;
288
289 case _NG_KEYBYHOST:
290 map = "netgroup.byhost";
291 break;
292
293 default:
294 abort();
295 break;
296 }
297
298
299 *line = NULL;
300 switch (yp_match(__ypdomain, map, name, (int)strlen(name), line, &i)) {
301 case 0:
302 return NS_SUCCESS;
303 case YPERR_KEY:
304 if (*line)
305 free(*line);
306 return NS_NOTFOUND;
307 default:
308 if (*line)
309 free(*line);
310 return NS_UNAVAIL;
311 }
312 /* NOTREACHED */
313 }
314 #endif
315
316 /*
317 * lookup(): Find the given key in the database or yp, and return its value
318 * in *line; returns 1 if key was found, 0 otherwise
319 */
320 static int
321 lookup(name, line, bywhat)
322 char *name;
323 char **line;
324 int bywhat;
325 {
326 int r;
327 static const ns_dtab dtab[] = {
328 NS_FILES_CB(_local_lookup, NULL)
329 NS_NIS_CB(_nis_lookup, NULL)
330 { 0 }
331 };
332
333 _DIAGASSERT(name != NULL);
334 _DIAGASSERT(line != NULL);
335
336 r = nsdispatch(NULL, dtab, NSDB_NETGROUP, "lookup", default_files_nis,
337 name, line, bywhat);
338 return (r == NS_SUCCESS) ? 1 : 0;
339 }
340
341 /*
342 * _ng_parse(): Parse a line and return: _NG_ERROR: Syntax Error _NG_NONE:
343 * line was empty or a comment _NG_GROUP: line had a netgroup definition,
344 * returned in ng _NG_NAME: line had a netgroup name, returned in name
345 *
346 * Public since used by netgroup_mkdb
347 */
348 int
349 _ng_parse(p, name, ng)
350 char **p;
351 char **name;
352 struct netgroup **ng;
353 {
354
355 _DIAGASSERT(p != NULL);
356 _DIAGASSERT(*p != NULL);
357 _DIAGASSERT(name != NULL);
358 _DIAGASSERT(ng != NULL);
359 #ifdef _DIAGNOSTIC
360 if (p == NULL || *p == NULL || name == NULL || ng == NULL)
361 return _NG_NONE;
362 #endif
363
364 while (**p) {
365 if (**p == '#')
366 /* comment */
367 return _NG_NONE;
368
369 while (**p && _NG_ISSPACE(**p))
370 /* skipblank */
371 (*p)++;
372
373 if (**p == '(') {
374 if ((*ng = getnetgroup(p)) == NULL) {
375 warnx("netgroup: Syntax error `%s'", *p);
376 return _NG_ERROR;
377 }
378 return _NG_GROUP;
379 } else {
380 char *np;
381 size_t i;
382
383 for (np = *p; **p && !_NG_ISSPACE(**p); (*p)++)
384 continue;
385 if (np != *p) {
386 i = (*p - np) + 1;
387 *name = malloc(i);
388 if (*name == NULL)
389 err(1, _ngoomem);
390 memcpy(*name, np, i);
391 (*name)[i - 1] = '\0';
392 return _NG_NAME;
393 }
394 }
395 }
396 return _NG_NONE;
397 }
398
399
400 /*
401 * addgroup(): Recursively add all the members of the netgroup to this group
402 */
403 static void
404 addgroup(sl, grp)
405 StringList *sl;
406 char *grp;
407 {
408 char *line, *p;
409 struct netgroup *ng;
410 char *name;
411
412 _DIAGASSERT(sl != NULL);
413 _DIAGASSERT(grp != NULL);
414
415 #ifdef DEBUG_NG
416 (void) fprintf(stderr, "addgroup(%s)\n", grp);
417 #endif
418 /* check for cycles */
419 if (sl_find(sl, grp) != NULL) {
420 free(grp);
421 warnx("netgroup: Cycle in group `%s'", grp);
422 return;
423 }
424 sl_add(sl, grp);
425
426 /* Lookup this netgroup */
427 line = NULL;
428 if (!lookup(grp, &line, _NG_KEYBYNAME)) {
429 if (line != NULL)
430 free(line);
431 return;
432 }
433
434 p = line;
435
436 for (;;) {
437 switch (_ng_parse(&p, &name, &ng)) {
438 case _NG_NONE:
439 /* Done with the line */
440 free(line);
441 return;
442
443 case _NG_GROUP:
444 /* new netgroup */
445 /* add to the list */
446 ng->ng_next = _nglist;
447 _nglist = ng;
448 break;
449
450 case _NG_NAME:
451 /* netgroup name */
452 addgroup(sl, name);
453 break;
454
455 case _NG_ERROR:
456 return;
457
458 default:
459 abort();
460 return;
461 }
462 }
463 }
464
465
466 /*
467 * in_check(): Compare the spec with the netgroup
468 */
469 static int
470 in_check(host, user, domain, ng)
471 const char *host;
472 const char *user;
473 const char *domain;
474 struct netgroup *ng;
475 {
476
477 /* host may be NULL */
478 /* user may be NULL */
479 /* domain may be NULL */
480 _DIAGASSERT(ng != NULL);
481
482 if ((host != NULL) && (ng->ng_host != NULL)
483 && strcmp(ng->ng_host, host) != 0)
484 return 0;
485
486 if ((user != NULL) && (ng->ng_user != NULL)
487 && strcmp(ng->ng_user, user) != 0)
488 return 0;
489
490 if ((domain != NULL) && (ng->ng_domain != NULL)
491 && strcmp(ng->ng_domain, domain) != 0)
492 return 0;
493
494 return 1;
495 }
496
497
498 /*
499 * in_find(): Find a match for the host, user, domain spec
500 */
501 static int
502 in_find(sl, grp, host, user, domain)
503 StringList *sl;
504 char *grp;
505 const char *host;
506 const char *user;
507 const char *domain;
508 {
509 char *line, *p;
510 int i;
511 struct netgroup *ng;
512 char *name;
513
514 _DIAGASSERT(sl != NULL);
515 _DIAGASSERT(grp != NULL);
516 /* host may be NULL */
517 /* user may be NULL */
518 /* domain may be NULL */
519
520 #ifdef DEBUG_NG
521 (void) fprintf(stderr, "in_find(%s)\n", grp);
522 #endif
523 /* check for cycles */
524 if (sl_find(sl, grp) != NULL) {
525 free(grp);
526 warnx("netgroup: Cycle in group `%s'", grp);
527 return 0;
528 }
529 sl_add(sl, grp);
530
531 /* Lookup this netgroup */
532 line = NULL;
533 if (!lookup(grp, &line, _NG_KEYBYNAME)) {
534 if (line)
535 free(line);
536 return 0;
537 }
538
539 p = line;
540
541 for (;;) {
542 switch (_ng_parse(&p, &name, &ng)) {
543 case _NG_NONE:
544 /* Done with the line */
545 free(line);
546 return 0;
547
548 case _NG_GROUP:
549 /* new netgroup */
550 i = in_check(host, user, domain, ng);
551 if (ng->ng_host != NULL)
552 free((char *)ng->ng_host);
553 if (ng->ng_user != NULL)
554 free((char *)ng->ng_user);
555 if (ng->ng_domain != NULL)
556 free((char *)ng->ng_domain);
557 free(ng);
558 if (i) {
559 free(line);
560 return 1;
561 }
562 break;
563
564 case _NG_NAME:
565 /* netgroup name */
566 if (in_find(sl, name, host, user, domain)) {
567 free(line);
568 return 1;
569 }
570 break;
571
572 case _NG_ERROR:
573 free(line);
574 return 0;
575
576 default:
577 abort();
578 return 0;
579 }
580 }
581 }
582
583
584 /*
585 * _ng_makekey(): Make a key from the two names given. The key is of the form
586 * <name1>.<name2> Names strings are replaced with * if they are empty;
587 */
588 char *
589 _ng_makekey(s1, s2, len)
590 const char *s1, *s2;
591 size_t len;
592 {
593 char *buf;
594
595 /* s1 may be NULL */
596 /* s2 may be NULL */
597
598 buf = malloc(len);
599 if (buf == NULL)
600 err(1, _ngoomem);
601 (void) snprintf(buf, len, "%s.%s", _NG_STAR(s1), _NG_STAR(s2));
602 return buf;
603 }
604
605 void
606 _ng_print(buf, len, ng)
607 char *buf;
608 size_t len;
609 const struct netgroup *ng;
610 {
611 _DIAGASSERT(buf != NULL);
612 _DIAGASSERT(ng != NULL);
613 #ifdef _DIAGNOSTIC
614 if (buf == NULL || ng == NULL)
615 return;
616 #endif
617
618 (void) snprintf(buf, len, "(%s,%s,%s)", _NG_EMPTY(ng->ng_host),
619 _NG_EMPTY(ng->ng_user), _NG_EMPTY(ng->ng_domain));
620 }
621
622
623 /*
624 * in_lookup1(): Fast lookup for a key in the appropriate map
625 */
626 static char *
627 in_lookup1(key, domain, map)
628 const char *key;
629 const char *domain;
630 int map;
631 {
632 char *line;
633 size_t len;
634 char *ptr;
635 int res;
636
637 /* key may be NULL */
638 /* domain may be NULL */
639
640 len = (key ? strlen(key) : 1) + (domain ? strlen(domain) : 1) + 2;
641 ptr = _ng_makekey(key, domain, len);
642 res = lookup(ptr, &line, map);
643 free(ptr);
644 return res ? line : NULL;
645 }
646
647
648 /*
649 * in_lookup(): Fast lookup for a key in the appropriate map
650 */
651 static int
652 in_lookup(group, key, domain, map)
653 const char *group;
654 const char *key;
655 const char *domain;
656 int map;
657 {
658 size_t len;
659 char *ptr, *line;
660
661 _DIAGASSERT(group != NULL);
662 /* key may be NULL */
663 /* domain may be NULL */
664
665 if (domain != NULL) {
666 /* Domain specified; look in "group.domain" and "*.domain" */
667 if ((line = in_lookup1(key, domain, map)) == NULL)
668 line = in_lookup1(NULL, domain, map);
669 }
670 else
671 line = NULL;
672
673 if (line == NULL) {
674 /*
675 * domain not specified or domain lookup failed; look in
676 * "group.*" and "*.*"
677 */
678 if (((line = in_lookup1(key, NULL, map)) == NULL) &&
679 ((line = in_lookup1(NULL, NULL, map)) == NULL))
680 return 0;
681 }
682
683 len = strlen(group);
684
685 for (ptr = line; (ptr = strstr(ptr, group)) != NULL;)
686 /* Make sure we did not find a substring */
687 if ((ptr != line && ptr[-1] != ',') ||
688 (ptr[len] != '\0' && strchr("\n\t ,", ptr[len]) == NULL))
689 ptr++;
690 else {
691 free(line);
692 return 1;
693 }
694
695 free(line);
696 return 0;
697 }
698
699
700 void
701 endnetgrent()
702 {
703 for (_nglist = _nghead; _nglist != NULL; _nglist = _nghead) {
704 _nghead = _nglist->ng_next;
705 if (_nglist->ng_host != NULL)
706 free((char *)_nglist->ng_host);
707 if (_nglist->ng_user != NULL)
708 free((char *)_nglist->ng_user);
709 if (_nglist->ng_domain != NULL)
710 free((char *)_nglist->ng_domain);
711 free(_nglist);
712 }
713
714 if (_ng_db) {
715 (void) (_ng_db->close) (_ng_db);
716 _ng_db = NULL;
717 }
718 }
719
720
721 void
722 setnetgrent(ng)
723 const char *ng;
724 {
725 StringList *sl = sl_init();
726 char *ng_copy;
727
728 _DIAGASSERT(ng != NULL);
729 #ifdef _DIAGNOSTIC
730 if (ng == NULL)
731 return;
732 #endif
733
734 /* Cleanup any previous storage */
735 if (_nghead != NULL)
736 endnetgrent();
737
738 if (_ng_db == NULL)
739 _ng_db = dbopen(_PATH_NETGROUP_DB, O_RDONLY, 0, DB_HASH, NULL);
740
741 ng_copy = strdup(ng);
742 if (ng_copy == NULL)
743 err(1, _ngoomem);
744 addgroup(sl, ng_copy);
745 _nghead = _nglist;
746 sl_free(sl, 1);
747 }
748
749
750 int
751 getnetgrent(host, user, domain)
752 const char **host;
753 const char **user;
754 const char **domain;
755 {
756 _DIAGASSERT(host != NULL);
757 _DIAGASSERT(user != NULL);
758 _DIAGASSERT(domain != NULL);
759 #ifdef _DIAGNOSTIC
760 if (host == NULL || user == NULL || domain == NULL)
761 return 0;
762 #endif
763
764 if (_nglist == NULL)
765 return 0;
766
767 *host = _nglist->ng_host;
768 *user = _nglist->ng_user;
769 *domain = _nglist->ng_domain;
770
771 _nglist = _nglist->ng_next;
772
773 return 1;
774 }
775
776
777 int
778 innetgr(grp, host, user, domain)
779 const char *grp, *host, *user, *domain;
780 {
781 int found;
782 StringList *sl;
783
784 _DIAGASSERT(grp != NULL);
785 /* host may be NULL */
786 /* user may be NULL */
787 /* domain may be NULL */
788 #ifdef _DIAGNOSTIC
789 if (grp == NULL)
790 return 0;
791 #endif
792
793 if (_ng_db == NULL)
794 _ng_db = dbopen(_PATH_NETGROUP_DB, O_RDONLY, 0, DB_HASH, NULL);
795
796 /* Try the fast lookup first */
797 if (host != NULL && user == NULL) {
798 if (in_lookup(grp, host, domain, _NG_KEYBYHOST))
799 return 1;
800 } else if (host == NULL && user != NULL) {
801 if (in_lookup(grp, user, domain, _NG_KEYBYUSER))
802 return 1;
803 }
804 /* If a domainname is given, we would have found a match */
805 if (domain != NULL)
806 return 0;
807
808 /* Too bad need the slow recursive way */
809 sl = sl_init();
810 found = in_find(sl, strdup(grp), host, user, domain);
811 sl_free(sl, 1);
812
813 return found;
814 }
815