getnetgrent.c revision 1.29 1 /* $NetBSD: getnetgrent.c,v 1.29 2002/05/26 14:03:20 wiz 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 1.29 2002/05/26 14:03:20 wiz 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 <stdarg.h>
51 #include <stdio.h>
52 #include <stdlib.h>
53 #include <string.h>
54 #include <stringlist.h>
55
56 #ifdef YP
57 #include <rpc/rpc.h>
58 #include <rpcsvc/ypclnt.h>
59 #include <rpcsvc/yp_prot.h>
60 #endif
61
62 #ifdef __weak_alias
63 __weak_alias(endnetgrent,_endnetgrent)
64 __weak_alias(getnetgrent,_getnetgrent)
65 __weak_alias(innetgr,_innetgr)
66 __weak_alias(setnetgrent,_setnetgrent)
67 #endif
68
69 #define _NG_STAR(s) (((s) == NULL || *(s) == '\0') ? _ngstar : s)
70 #define _NG_EMPTY(s) ((s) == NULL ? "" : s)
71 #define _NG_ISSPACE(p) (isspace((unsigned char) (p)) || (p) == '\n')
72
73 static const char _ngstar[] = "*";
74 static struct netgroup *_nghead = (struct netgroup *)NULL;
75 static struct netgroup *_nglist = (struct netgroup *)NULL;
76 static DB *_ng_db;
77
78 static int getstring __P((char **, int, __aconst char **));
79 static struct netgroup *getnetgroup __P((char **));
80 static int lookup __P((char *, char **, int));
81 static int addgroup __P((StringList *, char *));
82 static int in_check __P((const char *, const char *,
83 const char *, struct netgroup *));
84 static int in_find __P((StringList *, char *, const char *,
85 const char *, const char *));
86 static char *in_lookup1 __P((const char *, const char *, int));
87 static int in_lookup __P((const char *, const char *,
88 const char *, int));
89
90 static const ns_src default_files_nis[] = {
91 { NSSRC_FILES, NS_SUCCESS | NS_NOTFOUND },
92 #ifdef YP
93 { NSSRC_NIS, NS_SUCCESS },
94 #endif
95 { 0 }
96 };
97
98 /*
99 * getstring(): Get a string delimited by the character, skipping leading and
100 * trailing blanks and advancing the pointer
101 */
102 static int
103 getstring(pp, del, str)
104 char **pp;
105 int del;
106 char __aconst **str;
107 {
108 size_t len;
109 char *sp, *ep, *dp;
110
111 _DIAGASSERT(pp != NULL);
112 _DIAGASSERT(str != NULL);
113
114 /* skip leading blanks */
115 for (sp = *pp; *sp && _NG_ISSPACE(*sp); sp++)
116 continue;
117
118 /* accumulate till delimiter or space */
119 for (ep = sp; *ep && *ep != del && !_NG_ISSPACE(*ep); ep++)
120 continue;
121
122 /* hunt for the delimiter */
123 for (dp = ep; *dp && *dp != del && _NG_ISSPACE(*dp); dp++)
124 continue;
125
126 if (*dp != del) {
127 *str = NULL;
128 return 0;
129 }
130
131 *pp = ++dp;
132
133 len = (ep - sp) + 1;
134 if (len > 1) {
135 dp = malloc(len);
136 if (dp == NULL)
137 return 0;
138 memcpy(dp, sp, len);
139 dp[len - 1] = '\0';
140 } else
141 dp = NULL;
142
143 *str = dp;
144 return 1;
145 }
146
147
148 /*
149 * getnetgroup(): Parse a netgroup, and advance the pointer
150 */
151 static struct netgroup *
152 getnetgroup(pp)
153 char **pp;
154 {
155 struct netgroup *ng;
156
157 _DIAGASSERT(pp != NULL);
158 _DIAGASSERT(*pp != NULL);
159
160 ng = malloc(sizeof(struct netgroup));
161 if (ng == NULL)
162 return NULL;
163
164 (*pp)++; /* skip '(' */
165 if (!getstring(pp, ',', &ng->ng_host))
166 goto badhost;
167
168 if (!getstring(pp, ',', &ng->ng_user))
169 goto baduser;
170
171 if (!getstring(pp, ')', &ng->ng_domain))
172 goto baddomain;
173
174 #ifdef DEBUG_NG
175 {
176 char buf[1024];
177 (void) fprintf(stderr, "netgroup %s\n",
178 _ng_print(buf, sizeof(buf), ng));
179 }
180 #endif
181 return ng;
182
183 baddomain:
184 if (ng->ng_user)
185 free((char *)ng->ng_user);
186 baduser:
187 if (ng->ng_host)
188 free((char *)ng->ng_host);
189 badhost:
190 free(ng);
191 return NULL;
192 }
193
194
195 static int _local_lookup __P((void *, void *, va_list));
196
197 /*ARGSUSED*/
198 static int
199 _local_lookup(rv, cb_data, ap)
200 void *rv;
201 void *cb_data;
202 va_list ap;
203 {
204 char *name = va_arg(ap, char *);
205 char **line = va_arg(ap, char **);
206 int bywhat = va_arg(ap, int);
207
208 DBT key, data;
209 size_t len;
210 char *ks;
211 int r;
212
213 if (_ng_db == NULL)
214 return NS_UNAVAIL;
215
216 len = strlen(name) + 2;
217 ks = malloc(len);
218 if (ks == NULL)
219 return NS_UNAVAIL;
220
221 ks[0] = bywhat;
222 memcpy(&ks[1], name, len - 1);
223
224 key.data = (u_char *) ks;
225 key.size = len;
226
227 r = (_ng_db->get) (_ng_db, &key, &data, 0);
228 free(ks);
229 switch (r) {
230 case 0:
231 break;
232 case 1:
233 return NS_NOTFOUND;
234 case -1:
235 /* XXX: call endnetgrent() here ? */
236 return NS_UNAVAIL;
237 }
238
239 *line = strdup(data.data);
240 if (*line == NULL)
241 return NS_UNAVAIL;
242 return NS_SUCCESS;
243 }
244
245 #ifdef YP
246 static int _nis_lookup __P((void *, void *, va_list));
247
248 /*ARGSUSED*/
249 static int
250 _nis_lookup(rv, cb_data, ap)
251 void *rv;
252 void *cb_data;
253 va_list ap;
254 {
255 char *name = va_arg(ap, char *);
256 char **line = va_arg(ap, char **);
257 int bywhat = va_arg(ap, int);
258
259 static char *__ypdomain;
260 int i;
261 char *map = NULL;
262
263 if(__ypdomain == NULL) {
264 switch (yp_get_default_domain(&__ypdomain)) {
265 case 0:
266 break;
267 case YPERR_RESRC:
268 return NS_TRYAGAIN;
269 default:
270 return NS_UNAVAIL;
271 }
272 }
273
274 switch (bywhat) {
275 case _NG_KEYBYNAME:
276 map = "netgroup";
277 break;
278
279 case _NG_KEYBYUSER:
280 map = "netgroup.byuser";
281 break;
282
283 case _NG_KEYBYHOST:
284 map = "netgroup.byhost";
285 break;
286
287 default:
288 abort();
289 }
290
291 *line = NULL;
292 switch (yp_match(__ypdomain, map, name, (int)strlen(name), line, &i)) {
293 case 0:
294 return NS_SUCCESS;
295 case YPERR_KEY:
296 if (*line)
297 free(*line);
298 return NS_NOTFOUND;
299 default:
300 if (*line)
301 free(*line);
302 return NS_UNAVAIL;
303 }
304 /* NOTREACHED */
305 }
306 #endif
307
308
309 /*
310 * lookup(): Find the given key in the database or yp, and return its value
311 * in *line; returns 1 if key was found, 0 otherwise
312 */
313 static int
314 lookup(name, line, bywhat)
315 char *name;
316 char **line;
317 int bywhat;
318 {
319 int r;
320 static const ns_dtab dtab[] = {
321 NS_FILES_CB(_local_lookup, NULL)
322 NS_NIS_CB(_nis_lookup, NULL)
323 { 0 }
324 };
325
326 _DIAGASSERT(name != NULL);
327 _DIAGASSERT(line != NULL);
328
329 r = nsdispatch(NULL, dtab, NSDB_NETGROUP, "lookup", default_files_nis,
330 name, line, bywhat);
331 return (r == NS_SUCCESS) ? 1 : 0;
332 }
333
334 /*
335 * _ng_parse(): Parse a line and return: _NG_ERROR: Syntax Error _NG_NONE:
336 * line was empty or a comment _NG_GROUP: line had a netgroup definition,
337 * returned in ng _NG_NAME: line had a netgroup name, returned in name
338 *
339 * Public since used by netgroup_mkdb
340 */
341 int
342 _ng_parse(p, name, ng)
343 char **p;
344 char **name;
345 struct netgroup **ng;
346 {
347
348 _DIAGASSERT(p != NULL);
349 _DIAGASSERT(*p != NULL);
350 _DIAGASSERT(name != NULL);
351 _DIAGASSERT(ng != NULL);
352
353 while (**p) {
354 if (**p == '#')
355 /* comment */
356 return _NG_NONE;
357
358 while (**p && _NG_ISSPACE(**p))
359 /* skipblank */
360 (*p)++;
361
362 if (**p == '(') {
363 if ((*ng = getnetgroup(p)) == NULL)
364 return _NG_ERROR;
365 return _NG_GROUP;
366 } else {
367 char *np;
368 size_t i;
369
370 for (np = *p; **p && !_NG_ISSPACE(**p); (*p)++)
371 continue;
372 if (np != *p) {
373 i = (*p - np) + 1;
374 *name = malloc(i);
375 if (*name == NULL)
376 return _NG_ERROR;
377 memcpy(*name, np, i);
378 (*name)[i - 1] = '\0';
379 return _NG_NAME;
380 }
381 }
382 }
383 return _NG_NONE;
384 }
385
386
387 /*
388 * addgroup(): Recursively add all the members of the netgroup to this group.
389 * returns 0 upon failure, nonzero upon success.
390 * grp is not a valid pointer after return (either free(3)ed or allocated
391 * to a stringlist). in either case, it shouldn't be used again.
392 */
393 static int
394 addgroup(sl, grp)
395 StringList *sl;
396 char *grp;
397 {
398 char *line, *p;
399 struct netgroup *ng;
400 char *name;
401
402 _DIAGASSERT(sl != NULL);
403 _DIAGASSERT(grp != NULL);
404
405 #ifdef DEBUG_NG
406 (void) fprintf(stderr, "addgroup(%s)\n", grp);
407 #endif
408 /* check for cycles */
409 if (sl_find(sl, grp) != NULL) {
410 free(grp);
411 warnx("netgroup: Cycle in group `%s'", grp);
412 return 0;
413 }
414 if (sl_add(sl, grp) == -1) {
415 free(grp);
416 return 0;
417 }
418
419 /* Lookup this netgroup */
420 line = NULL;
421 if (!lookup(grp, &line, _NG_KEYBYNAME)) {
422 if (line != NULL)
423 free(line);
424 return 0;
425 }
426
427 p = line;
428
429 for (;;) {
430 switch (_ng_parse(&p, &name, &ng)) {
431 case _NG_NONE:
432 /* Done with the line */
433 free(line);
434 return 1;
435
436 case _NG_GROUP:
437 /* new netgroup */
438 /* add to the list */
439 ng->ng_next = _nglist;
440 _nglist = ng;
441 break;
442
443 case _NG_NAME:
444 /* netgroup name */
445 if (!addgroup(sl, name))
446 return 0;
447 break;
448
449 case _NG_ERROR:
450 return 0;
451
452 default:
453 abort();
454 }
455 }
456 }
457
458
459 /*
460 * in_check(): Compare the spec with the netgroup
461 */
462 static int
463 in_check(host, user, domain, ng)
464 const char *host;
465 const char *user;
466 const char *domain;
467 struct netgroup *ng;
468 {
469
470 /* host may be NULL */
471 /* user may be NULL */
472 /* domain may be NULL */
473 _DIAGASSERT(ng != NULL);
474
475 if ((host != NULL) && (ng->ng_host != NULL)
476 && strcmp(ng->ng_host, host) != 0)
477 return 0;
478
479 if ((user != NULL) && (ng->ng_user != NULL)
480 && strcmp(ng->ng_user, user) != 0)
481 return 0;
482
483 if ((domain != NULL) && (ng->ng_domain != NULL)
484 && strcmp(ng->ng_domain, domain) != 0)
485 return 0;
486
487 return 1;
488 }
489
490
491 /*
492 * in_find(): Find a match for the host, user, domain spec.
493 * grp is not a valid pointer after return (either free(3)ed or allocated
494 * to a stringlist). in either case, it shouldn't be used again.
495 */
496 static int
497 in_find(sl, grp, host, user, domain)
498 StringList *sl;
499 char *grp;
500 const char *host;
501 const char *user;
502 const char *domain;
503 {
504 char *line, *p;
505 int i;
506 struct netgroup *ng;
507 char *name;
508
509 _DIAGASSERT(sl != NULL);
510 _DIAGASSERT(grp != NULL);
511 /* host may be NULL */
512 /* user may be NULL */
513 /* domain may be NULL */
514
515 #ifdef DEBUG_NG
516 (void) fprintf(stderr, "in_find(%s)\n", grp);
517 #endif
518 /* check for cycles */
519 if (sl_find(sl, grp) != NULL) {
520 free(grp);
521 warnx("netgroup: Cycle in group `%s'", grp);
522 return 0;
523 }
524 if (sl_add(sl, grp) == -1) {
525 free(grp);
526 return 0;
527 }
528
529 /* Lookup this netgroup */
530 line = NULL;
531 if (!lookup(grp, &line, _NG_KEYBYNAME)) {
532 if (line)
533 free(line);
534 return 0;
535 }
536
537 p = line;
538
539 for (;;) {
540 switch (_ng_parse(&p, &name, &ng)) {
541 case _NG_NONE:
542 /* Done with the line */
543 free(line);
544 return 0;
545
546 case _NG_GROUP:
547 /* new netgroup */
548 i = in_check(host, user, domain, ng);
549 if (ng->ng_host != NULL)
550 free((char *)ng->ng_host);
551 if (ng->ng_user != NULL)
552 free((char *)ng->ng_user);
553 if (ng->ng_domain != NULL)
554 free((char *)ng->ng_domain);
555 free(ng);
556 if (i) {
557 free(line);
558 return 1;
559 }
560 break;
561
562 case _NG_NAME:
563 /* netgroup name */
564 if (in_find(sl, name, host, user, domain)) {
565 free(line);
566 return 1;
567 }
568 break;
569
570 case _NG_ERROR:
571 free(line);
572 return 0;
573
574 default:
575 abort();
576 }
577 }
578 }
579
580 /*
581 * _ng_makekey(): Make a key from the two names given. The key is of the form
582 * <name1>.<name2> Names strings are replaced with * if they are empty;
583 * Returns NULL if there's a problem.
584 */
585 char *
586 _ng_makekey(s1, s2, len)
587 const char *s1, *s2;
588 size_t len;
589 {
590 char *buf;
591
592 /* s1 may be NULL */
593 /* s2 may be NULL */
594
595 buf = malloc(len);
596 if (buf != NULL)
597 (void) snprintf(buf, len, "%s.%s", _NG_STAR(s1), _NG_STAR(s2));
598 return buf;
599 }
600
601 void
602 _ng_print(buf, len, ng)
603 char *buf;
604 size_t len;
605 const struct netgroup *ng;
606 {
607 _DIAGASSERT(buf != NULL);
608 _DIAGASSERT(ng != NULL);
609
610 (void) snprintf(buf, len, "(%s,%s,%s)", _NG_EMPTY(ng->ng_host),
611 _NG_EMPTY(ng->ng_user), _NG_EMPTY(ng->ng_domain));
612 }
613
614
615 /*
616 * in_lookup1(): Fast lookup for a key in the appropriate map
617 */
618 static char *
619 in_lookup1(key, domain, map)
620 const char *key;
621 const char *domain;
622 int map;
623 {
624 char *line;
625 size_t len;
626 char *ptr;
627 int res;
628
629 /* key may be NULL */
630 /* domain may be NULL */
631
632 len = (key ? strlen(key) : 1) + (domain ? strlen(domain) : 1) + 2;
633 ptr = _ng_makekey(key, domain, len);
634 if (ptr == NULL)
635 return NULL;
636 res = lookup(ptr, &line, map);
637 free(ptr);
638 return res ? line : NULL;
639 }
640
641
642 /*
643 * in_lookup(): Fast lookup for a key in the appropriate map
644 */
645 static int
646 in_lookup(group, key, domain, map)
647 const char *group;
648 const char *key;
649 const char *domain;
650 int map;
651 {
652 size_t len;
653 char *ptr, *line;
654
655 _DIAGASSERT(group != NULL);
656 /* key may be NULL */
657 /* domain may be NULL */
658
659 if (domain != NULL) {
660 /* Domain specified; look in "group.domain" and "*.domain" */
661 if ((line = in_lookup1(key, domain, map)) == NULL)
662 line = in_lookup1(NULL, domain, map);
663 } else
664 line = NULL;
665
666 if (line == NULL) {
667 /*
668 * domain not specified or domain lookup failed; look in
669 * "group.*" and "*.*"
670 */
671 if (((line = in_lookup1(key, NULL, map)) == NULL) &&
672 ((line = in_lookup1(NULL, NULL, map)) == NULL))
673 return 0;
674 }
675
676 len = strlen(group);
677
678 for (ptr = line; (ptr = strstr(ptr, group)) != NULL;)
679 /* Make sure we did not find a substring */
680 if ((ptr != line && ptr[-1] != ',') ||
681 (ptr[len] != '\0' && strchr("\n\t ,", ptr[len]) == NULL))
682 ptr++;
683 else {
684 free(line);
685 return 1;
686 }
687
688 free(line);
689 return 0;
690 }
691
692
693 void
694 endnetgrent()
695 {
696 for (_nglist = _nghead; _nglist != NULL; _nglist = _nghead) {
697 _nghead = _nglist->ng_next;
698 if (_nglist->ng_host != NULL)
699 free((char *)_nglist->ng_host);
700 if (_nglist->ng_user != NULL)
701 free((char *)_nglist->ng_user);
702 if (_nglist->ng_domain != NULL)
703 free((char *)_nglist->ng_domain);
704 free(_nglist);
705 }
706
707 if (_ng_db) {
708 (void) (_ng_db->close) (_ng_db);
709 _ng_db = NULL;
710 }
711 }
712
713
714 void
715 setnetgrent(ng)
716 const char *ng;
717 {
718 StringList *sl;
719 char *ng_copy;
720
721 _DIAGASSERT(ng != NULL);
722
723 sl = sl_init();
724 if (sl == NULL)
725 return;
726
727 /* Cleanup any previous storage */
728 if (_nghead != NULL)
729 endnetgrent();
730
731 if (_ng_db == NULL)
732 _ng_db = dbopen(_PATH_NETGROUP_DB, O_RDONLY, 0, DB_HASH, NULL);
733
734 ng_copy = strdup(ng);
735 if (ng_copy != NULL)
736 addgroup(sl, ng_copy);
737 _nghead = _nglist;
738 sl_free(sl, 1);
739 }
740
741
742 int
743 getnetgrent(host, user, domain)
744 const char **host;
745 const char **user;
746 const char **domain;
747 {
748 _DIAGASSERT(host != NULL);
749 _DIAGASSERT(user != NULL);
750 _DIAGASSERT(domain != NULL);
751
752 if (_nglist == NULL)
753 return 0;
754
755 *host = _nglist->ng_host;
756 *user = _nglist->ng_user;
757 *domain = _nglist->ng_domain;
758
759 _nglist = _nglist->ng_next;
760
761 return 1;
762 }
763
764
765 int
766 innetgr(grp, host, user, domain)
767 const char *grp, *host, *user, *domain;
768 {
769 int found;
770 StringList *sl;
771
772 _DIAGASSERT(grp != NULL);
773 /* host may be NULL */
774 /* user may be NULL */
775 /* domain may be NULL */
776
777 if (_ng_db == NULL)
778 _ng_db = dbopen(_PATH_NETGROUP_DB, O_RDONLY, 0, DB_HASH, NULL);
779
780 /* Try the fast lookup first */
781 if (host != NULL && user == NULL) {
782 if (in_lookup(grp, host, domain, _NG_KEYBYHOST))
783 return 1;
784 } else if (host == NULL && user != NULL) {
785 if (in_lookup(grp, user, domain, _NG_KEYBYUSER))
786 return 1;
787 }
788 /* If a domainname is given, we would have found a match */
789 if (domain != NULL)
790 return 0;
791
792 /* Too bad need the slow recursive way */
793 sl = sl_init();
794 if (sl == NULL)
795 return 0;
796 found = in_find(sl, strdup(grp), host, user, domain);
797 sl_free(sl, 1);
798
799 return found;
800 }
801