kern_auth.c revision 1.1.2.4 1 /* $NetBSD: kern_auth.c,v 1.1.2.4 2006/03/08 16:44:57 elad Exp $ */
2
3 /*-
4 * Copyright (c) 2005, 2006 Elad Efrat <elad (at) NetBSD.org>
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 Elad Efrat.
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 OR
22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 */
32
33 /*
34 * Todo:
35 * - Garbage collection to pool_put() unused scopes/listeners.
36 */
37
38 #include <sys/types.h>
39 #include <sys/param.h>
40 #include <sys/queue.h>
41 #include <sys/time.h>
42 #include <sys/proc.h>
43 #include <sys/ucred.h>
44 #include <sys/pool.h>
45 #include <sys/kauth.h>
46 #include <sys/acct.h>
47
48 /*
49 * Credentials.
50 */
51 struct kauth_cred {
52 struct simplelock cr_lock; /* lock */
53 uint32_t cr_refcnt; /* reference count */
54 uid_t cr_uid; /* user id */
55 uid_t cr_euid; /* effective user id */
56 uid_t cr_svuid; /* saved effective user id */
57 gid_t cr_gid; /* group id */
58 gid_t cr_egid; /* effective group id */
59 gid_t cr_svgid; /* saved effective group id */
60 uint16_t cr_ngroups; /* number of groups */
61 gid_t cr_groups[NGROUPS]; /* group memberships */
62 };
63
64 /*
65 * Listener.
66 */
67 struct kauth_listener {
68 kauth_scope_callback_t func; /* callback */
69 kauth_scope_t scope; /* scope backpointer */
70 uint32_t refcnt; /* reference count */
71 SIMPLEQ_ENTRY(kauth_listener) listener_next; /* listener list */
72 };
73
74 /*
75 * Scope.
76 */
77 struct kauth_scope {
78 const char *id; /* scope name */
79 void *cookie; /* user cookie */
80 uint32_t nlisteners; /* # of listeners */
81 SIMPLEQ_HEAD(, kauth_listener) listenq; /* listener list */
82 SIMPLEQ_ENTRY(kauth_scope) next_scope; /* scope list */
83 };
84
85 POOL_INIT(kauth_scope_pool, sizeof(struct kauth_scope), 0, 0, 0,
86 "kauth_scopepl", &pool_allocator_nointr);
87 POOL_INIT(kauth_listener_pool, sizeof(struct kauth_listener), 0, 0, 0,
88 "kauth_listenerpl", &pool_allocator_nointr);
89 POOL_INIT(kauth_cred_pool, sizeof(struct kauth_cred), 0, 0, 0,
90 "kauth_credpl", &pool_allocator_nointr);
91
92 /* List of scopes and its lock. */
93 SIMPLEQ_HEAD(, kauth_scope) scope_list;
94 struct simplelock scopes_lock;
95
96 /* Built-in scopes: generic, process. */
97 kauth_scope_t builtin_generic;
98 kauth_scope_t builtin_process;
99
100 /* Allocate new, empty kauth credentials. */
101 kauth_cred_t
102 kauth_cred_alloc(void) {
103 kauth_cred_t cred;
104
105 cred = pool_get(&kauth_cred_pool, PR_WAITOK);
106 memset(cred, 0, sizeof(*cred));
107 simple_lock_init(&cred->cr_lock);
108 cred->cr_refcnt = 1;
109
110 return (cred);
111 }
112
113 /* Increment reference count to cred. */
114 void
115 kauth_cred_hold(kauth_cred_t cred)
116 {
117 KASSERT(cred != NULL);
118
119 simple_lock(&cred->cr_lock);
120 cred->cr_refcnt++;
121 simple_unlock(&cred->cr_lock);
122 }
123
124 void
125 kauth_cred_destroy(kauth_cred_t cred)
126 {
127 KASSERT(cred != NULL);
128
129 if (simple_lock_held(&cred->cr_lock)) /* XXX elad */
130 simple_unlock(&cred->cr_lock);
131
132 /* XXX: For debugging. */
133 memset(cred, 0, sizeof(*cred));
134
135 pool_put(&kauth_cred_pool, cred);
136 }
137
138 /* Decrease reference count to cred. If reached zero, free it. */
139 void
140 kauth_cred_free(kauth_cred_t cred) {
141 KASSERT(cred != NULL);
142
143 simple_lock(&cred->cr_lock);
144 cred->cr_refcnt--;
145 if (cred->cr_refcnt == 0)
146 kauth_cred_destroy(cred);
147 else
148 simple_unlock(&cred->cr_lock);
149 }
150
151 void
152 kauth_cred_clone(kauth_cred_t from, kauth_cred_t to)
153 {
154 KASSERT(from != NULL);
155 KASSERT(to != NULL);
156
157 to->cr_uid = from->cr_uid;
158 to->cr_euid = from->cr_euid;
159 to->cr_svuid = from->cr_svuid;
160 to->cr_gid = from->cr_gid;
161 to->cr_egid = from->cr_egid;
162 to->cr_svgid = from->cr_svgid;
163 to->cr_ngroups = from->cr_ngroups;
164 memcpy(to->cr_groups, from->cr_groups,
165 sizeof(to->cr_groups));
166 }
167
168 /*
169 * Duplicate cred and return a new kauth_cred_t.
170 */
171 kauth_cred_t
172 kauth_cred_dup(kauth_cred_t cred)
173 {
174 kauth_cred_t new_cred;
175
176 KASSERT(cred != NULL);
177
178 new_cred = kauth_cred_alloc();
179
180 kauth_cred_clone(cred, new_cred);
181
182 return (new_cred);
183 }
184
185 /*
186 * Similar to crcopy(), only on a kauth_cred_t.
187 * XXX: Is this even needed? [kauth_cred_copy]
188 */
189 kauth_cred_t
190 kauth_cred_copy(kauth_cred_t cred)
191 {
192 kauth_cred_t new_cred;
193
194 KASSERT(cred != NULL);
195
196 /* If the provided credentials already have one reference, use them. */
197 if (cred->cr_refcnt == 1)
198 return (cred);
199
200 new_cred = kauth_cred_alloc();
201
202 kauth_cred_clone(cred, new_cred);
203
204 kauth_cred_destroy(cred);
205
206 return (new_cred);
207 }
208
209 /*
210 * Zero a kauth_cred_t, and re-initialize the lock.
211 * XXX: Is this needed? [kauth_cred_zero]
212 */
213 void
214 kauth_cred_zero(kauth_cred_t cred)
215 {
216 KASSERT(cred != NULL);
217
218 memset(cred, 0, sizeof(*cred));
219 simple_lock_init(&cred->cr_lock);
220 }
221
222 uid_t
223 kauth_cred_getuid(kauth_cred_t cred)
224 {
225 KASSERT(cred != NULL);
226
227 return (cred->cr_uid);
228 }
229
230 uid_t
231 kauth_cred_geteuid(kauth_cred_t cred)
232 {
233 KASSERT(cred != NULL);
234
235 return (cred->cr_euid);
236 }
237
238 uid_t
239 kauth_cred_getsvuid(kauth_cred_t cred)
240 {
241 KASSERT(cred != NULL);
242
243 return (cred->cr_svuid);
244 }
245
246 gid_t
247 kauth_cred_getgid(kauth_cred_t cred)
248 {
249 KASSERT(cred != NULL);
250
251 return (cred->cr_gid);
252 }
253
254 gid_t
255 kauth_cred_getegid(kauth_cred_t cred)
256 {
257 KASSERT(cred != NULL);
258
259 return (cred->cr_egid);
260 }
261
262 gid_t
263 kauth_cred_getsvgid(kauth_cred_t cred)
264 {
265 KASSERT(cred != NULL);
266
267 return (cred->cr_svgid);
268 }
269
270 void
271 kauth_cred_setuid(kauth_cred_t cred, uid_t uid)
272 {
273 KASSERT(cred != NULL);
274 KASSERT(uid >= 0 && uid <= UID_MAX);
275
276 cred->cr_uid = uid;
277 }
278
279 void
280 kauth_cred_seteuid(kauth_cred_t cred, uid_t uid)
281 {
282 KASSERT(cred != NULL);
283 KASSERT(uid >= 0 && uid <= UID_MAX);
284
285 cred->cr_euid = uid;
286 }
287
288 void
289 kauth_cred_setsvuid(kauth_cred_t cred, uid_t uid)
290 {
291 KASSERT(cred != NULL);
292 KASSERT(uid >= 0 && uid <= UID_MAX);
293
294 cred->cr_svuid = uid;
295 }
296
297 void
298 kauth_cred_setgid(kauth_cred_t cred, gid_t gid)
299 {
300 KASSERT(cred != NULL);
301 KASSERT(gid >= 0 && gid <= GID_MAX);
302
303 cred->cr_gid = gid;
304 }
305
306 void
307 kauth_cred_setegid(kauth_cred_t cred, gid_t gid)
308 {
309 KASSERT(cred != NULL);
310 KASSERT(gid >= 0 && gid <= GID_MAX);
311
312 cred->cr_egid = gid;
313 }
314
315 void
316 kauth_cred_setsvgid(kauth_cred_t cred, gid_t gid)
317 {
318 KASSERT(cred != NULL);
319 KASSERT(gid >= 0 && gid <= GID_MAX);
320
321 cred->cr_svgid = gid;
322 }
323
324 /* Checks if gid is a member of the groups in cred. */
325 int
326 kauth_cred_groupmember(kauth_cred_t cred, gid_t gid)
327 {
328 int i;
329
330 KASSERT(cred != NULL);
331 KASSERT(gid >= 0 && gid <= GID_MAX);
332
333 for (i = 0; i < cred->cr_ngroups; i++) {
334 if (cred->cr_groups[i] == gid)
335 return (1);
336 }
337
338 return (0);
339 }
340
341 uint16_t
342 kauth_cred_ngroups(kauth_cred_t cred)
343 {
344 KASSERT(cred != NULL);
345
346 return (cred->cr_ngroups);
347 }
348
349 /*
350 * Return the group at index idx from the groups in cred.
351 */
352 gid_t
353 kauth_cred_group(kauth_cred_t cred, uint16_t idx)
354 {
355 KASSERT(cred != NULL);
356 KASSERT(idx < cred->cr_ngroups);
357
358 return (cred->cr_groups[idx]);
359 }
360
361 /* XXX: Is this needed? [setngroups] */
362 void
363 kauth_cred_setngroups(kauth_cred_t cred, uint16_t ngroups)
364 {
365 KASSERT(cred != NULL);
366 KASSERT(ngroups < NGROUPS);
367
368 cred->cr_ngroups = ngroups;
369 }
370
371 /* Sort len groups in grbuf. */
372 static void
373 kauth_cred_sortgroups(gid_t *grbuf, size_t len)
374 {
375 int i, j;
376 gid_t v;
377
378 KASSERT(grbuf != NULL);
379
380 /* Insertion sort. */
381 for (i = 1; i < len; i++) {
382 v = grbuf[i];
383 /* find correct slot for value v, moving others up */
384 for (j = i; --j >= 0 && v < grbuf[j];)
385 grbuf[j + 1] = grbuf[j];
386 grbuf[j + 1] = v;
387 }
388 }
389
390 /* Add group gid to groups in cred. Maintain order. */
391 int
392 kauth_cred_addgroup(kauth_cred_t cred, gid_t gid)
393 {
394 KASSERT(cred != NULL);
395 KASSERT(gid >= 0 && gid <= GID_MAX);
396
397 simple_lock(&cred->cr_lock);
398
399 if (cred->cr_ngroups >=
400 (sizeof(cred->cr_groups) / sizeof(cred->cr_groups[0]))) {
401 simple_unlock(&cred->cr_lock);
402 return (E2BIG);
403 }
404
405 if (kauth_cred_groupmember(cred, gid)) {
406 simple_unlock(&cred->cr_lock);
407 return (0);
408 }
409
410 cred->cr_groups[cred->cr_ngroups++] = gid;
411
412 kauth_cred_sortgroups(cred->cr_groups, cred->cr_ngroups);
413
414 simple_unlock(&cred->cr_lock);
415
416 return (0);
417 }
418
419 /* Delete group gid from groups in cred. Maintain order. */
420 int
421 kauth_cred_delgroup(kauth_cred_t cred, gid_t gid)
422 {
423 KASSERT(cred != NULL);
424 KASSERT(gid >= 0 && gid <= GID_MAX);
425
426 simple_lock(&cred->cr_lock);
427
428 if (!kauth_cred_groupmember(cred, gid)) {
429 simple_unlock(&cred->cr_lock);
430 return (0);
431 }
432
433 if (cred->cr_ngroups == 1)
434 cred->cr_groups[0] = (gid_t)-1; /* XXX */
435 else {
436 int i;
437
438 for (i = 0; i < cred->cr_ngroups; i++)
439 if (cred->cr_groups[i] == gid) {
440 cred->cr_groups[i] = cred->cr_groups[cred->cr_ngroups - 1];
441 cred->cr_groups[cred->cr_ngroups - 1] = (gid_t)-1; /* XXX */
442 }
443 }
444
445 cred->cr_ngroups--;
446
447 kauth_cred_sortgroups(cred->cr_groups, cred->cr_ngroups);
448
449 simple_unlock(&cred->cr_lock);
450
451 return (0);
452 }
453
454 /*
455 * Match uids in two credentials. Checks if cred1 can access stuff owned by
456 * cred2.
457 * XXX: root bypasses this!
458 */
459 int
460 kauth_cred_uidmatch(kauth_cred_t cred1, kauth_cred_t cred2)
461 {
462 KASSERT(cred1 != NULL);
463 KASSERT(cred2 != NULL);
464
465 /* Are we root? */
466 if (cred1->cr_euid == 0)
467 return (1);
468
469 if (cred1->cr_uid == cred2->cr_uid ||
470 cred1->cr_euid == cred2->cr_uid ||
471 cred1->cr_uid == cred2->cr_euid ||
472 cred1->cr_euid == cred2->cr_euid)
473 return (1);
474
475 return (0);
476 }
477
478 uint32_t
479 kauth_cred_getrefcnt(kauth_cred_t cred)
480 {
481 KASSERT(cred != NULL);
482
483 return (cred->cr_refcnt);
484 }
485
486 void
487 kauth_cred_setrefcnt(kauth_cred_t cred, uint32_t refcnt)
488 {
489 KASSERT(cred != NULL);
490
491 cred->cr_refcnt = refcnt;
492 }
493
494 /* XXX: memcmp() wrapper needed for NFSW_SAMECRED() in nfs/nfs.h */
495 int
496 kauth_cred_memcmp(kauth_cred_t cred1, kauth_cred_t cred2)
497 {
498 KASSERT(cred1 != NULL);
499 KASSERT(cred2 != NULL);
500
501 return (memcmp(cred1, cred2, sizeof(*cred1)));
502 }
503
504 /*
505 * Convert userland credentials (struct uucred) to kauth_cred_t.
506 * XXX: For NFS code.
507 */
508 void
509 kauth_cred_convert(kauth_cred_t cred, const struct uucred *uuc)
510 {
511 int i;
512
513 KASSERT(cred != NULL);
514 KASSERT(uuc != NULL);
515
516 cred->cr_refcnt = 0;
517 cred->cr_euid = uuc->cr_uid;
518 cred->cr_egid = uuc->cr_gid;
519 cred->cr_ngroups = min(uuc->cr_ngroups, NGROUPS);
520 for (i = 0; i < cred->cr_ngroups; i++)
521 kauth_cred_addgroup(cred, uuc->cr_groups[i]);
522 }
523
524 /*
525 * Compare kauth_cred_t and uucred credentials.
526 * XXX: Modelled after crcmp() for NFS.
527 */
528 int
529 kauth_cred_compare(kauth_cred_t cred, const struct uucred *uuc)
530 {
531 KASSERT(cred != NULL);
532 KASSERT(uuc != NULL);
533
534 if (cred->cr_euid == uuc->cr_uid &&
535 cred->cr_egid == uuc->cr_gid &&
536 cred->cr_ngroups == uuc->cr_ngroups &&
537 !memcmp(cred->cr_groups, uuc->cr_groups,
538 cred->cr_ngroups * sizeof(cred->cr_groups[0])))
539 return (1);
540
541 return (0);
542 }
543
544 /*
545 * Make a struct ucred out of a kauth_cred_t.
546 * XXX: For sysctl.
547 */
548 void
549 kauth_cred_toucred(kauth_cred_t cred, struct ucred *uc)
550 {
551 KASSERT(cred != NULL);
552 KASSERT(uc != NULL);
553
554 uc->cr_uid = cred->cr_euid;
555 uc->cr_gid = cred->cr_egid;
556 uc->cr_ngroups = min(cred->cr_ngroups,
557 sizeof(uc->cr_groups) / sizeof(uc->cr_groups[0]));
558 memcpy(uc->cr_groups, cred->cr_groups,
559 uc->cr_ngroups * sizeof(uc->cr_groups[0]));
560 }
561
562 /*
563 * Make a struct pcred out of a kauth_cred_t.
564 * XXX: For sysctl.
565 */
566 void
567 kauth_cred_topcred(kauth_cred_t cred, struct pcred *pc)
568 {
569 KASSERT(cred != NULL);
570 KASSERT(pc != NULL);
571
572 pc->pc_ucred = (struct ucred *)cred; /* XXX this is just wrong */
573 pc->p_ruid = cred->cr_uid;
574 pc->p_svuid = cred->cr_svuid;
575 pc->p_rgid = cred->cr_gid;
576 pc->p_svgid = cred->cr_svgid;
577 pc->p_refcnt = cred->cr_refcnt;
578 }
579
580 /*
581 * Returns a scope matching the provided id.
582 * Requires the scope list lock to be held by the caller.
583 */
584 static kauth_scope_t
585 kauth_ifindscope(const char *id) {
586 kauth_scope_t scope;
587
588 /* XXX: assert lock on scope list? */
589
590 scope = NULL;
591 SIMPLEQ_FOREACH(scope, &scope_list, next_scope) {
592 if (strcmp(scope->id, id) == 0)
593 break;
594 }
595
596 return (scope);
597 }
598
599 /*
600 * Register a new scope.
601 *
602 * id - identifier for the scope
603 * callback - the scope's default listener
604 * cookie - cookie to be passed to the listener(s)
605 */
606 kauth_scope_t
607 kauth_register_scope(const char *id, kauth_scope_callback_t callback,
608 void *cookie)
609 {
610 kauth_scope_t scope;
611 kauth_listener_t listener;
612
613 /* Sanitize input */
614 if (id == NULL || callback == NULL)
615 return (NULL);
616
617 /* Allocate space for a new scope and listener. */
618 scope = pool_get(&kauth_scope_pool, PR_WAITOK);
619 listener = pool_get(&kauth_listener_pool, PR_WAITOK);
620
621 /* Acquire scope list lock. */
622 simple_lock(&scopes_lock);
623
624 /* Check we don't already have a scope with the same id */
625 if (kauth_ifindscope(id) != NULL) {
626 simple_unlock(&scopes_lock);
627
628 pool_put(&kauth_scope_pool, scope);
629 pool_put(&kauth_listener_pool, listener);
630
631 return (NULL);
632 }
633
634 /* Initialize new scope with parameters */
635 scope->id = id;
636 scope->cookie = cookie;
637 scope->nlisteners = 1;
638
639 /* Add default listener */
640 listener->func = callback;
641 listener->scope = scope;
642 listener->refcnt = 0;
643 SIMPLEQ_INIT(&scope->listenq);
644 SIMPLEQ_INSERT_HEAD(&scope->listenq, listener, listener_next);
645
646 /* Insert scope to scopes list */
647 if (SIMPLEQ_EMPTY(&scope_list))
648 SIMPLEQ_INSERT_HEAD(&scope_list, scope, next_scope);
649 else
650 SIMPLEQ_INSERT_TAIL(&scope_list, scope, next_scope);
651
652 simple_unlock(&scopes_lock);
653
654 return (scope);
655 }
656
657 /*
658 * Initialize the kernel authorization subsystem.
659 *
660 * Initialize the scopes list lock.
661 * Register built-in scopes: generic, process.
662 */
663 void
664 kauth_init(void)
665 {
666 simple_lock_init(&scopes_lock);
667
668 /* Register generic scope. */
669 builtin_generic = kauth_register_scope(KAUTH_SCOPE_GENERIC,
670 kauth_authorize_cb_generic,
671 NULL);
672
673 /* Register process scope. */
674 builtin_process = kauth_register_scope(KAUTH_SCOPE_PROCESS,
675 kauth_authorize_cb_process,
676 NULL);
677 }
678
679 /*
680 * Deregister a scope.
681 * Requires scope list lock to be held by the caller.
682 *
683 * scope - the scope to deregister
684 */
685 void
686 kauth_deregister_scope(kauth_scope_t scope)
687 {
688 if (scope != NULL) {
689 /* Remove scope from list */
690 SIMPLEQ_REMOVE(&scope_list, scope, kauth_scope, next_scope);
691 }
692 }
693
694 /*
695 * Register a listener.
696 *
697 * id - scope identifier.
698 * callback - the callback routine for the listener.
699 * cookie - cookie to pass unmoidfied to the callback.
700 */
701 kauth_listener_t
702 kauth_listen_scope(const char *id, kauth_scope_callback_t callback,
703 void *cookie)
704 {
705 kauth_scope_t scope;
706 kauth_listener_t listener;
707
708 /* Find scope struct */
709 simple_lock(&scopes_lock);
710 scope = kauth_ifindscope(id);
711 simple_unlock(&scopes_lock);
712 if (scope == NULL)
713 return (NULL);
714
715 /* Allocate listener */
716 listener = pool_get(&kauth_listener_pool, PR_WAITOK);
717
718 /* Initialize listener with parameters */
719 listener->func = callback;
720 listener->refcnt = 0;
721
722 /* Add listener to scope */
723 SIMPLEQ_INSERT_TAIL(&scope->listenq, listener, listener_next);
724
725 /* Raise number of listeners on scope. */
726 scope->nlisteners++;
727 listener->scope = scope;
728
729 return (listener);
730 }
731
732 /*
733 * Deregister a listener.
734 *
735 * listener - listener reference as returned from kauth_listen_scope().
736 */
737 void
738 kauth_unlisten_scope(kauth_listener_t listener)
739 {
740 if (listener != NULL) {
741 SIMPLEQ_REMOVE(&listener->scope->listenq, listener, kauth_listener,
742 listener_next);
743 listener->scope->nlisteners--;
744 }
745 }
746
747 /*
748 * Authorize a request.
749 *
750 * scope - the scope of the request as defined by KAUTH_SCOPE_* or as
751 * returned from kauth_register_scope().
752 * credential - credentials of the user ("actor") making the request.
753 * action - request identifier.
754 * arg[0-3] - passed unmodified to listener(s).
755 */
756 int
757 kauth_authorize_action(kauth_scope_t scope, kauth_cred_t cred,
758 kauth_action_t action, void *arg0, void *arg1,
759 void *arg2, void *arg3)
760 {
761 kauth_listener_t listener;
762 int error, allow, fail;
763
764 /* Sanitize input */
765 if (scope == NULL || cred == NULL)
766 return (EFAULT);
767 if (!action)
768 return (EINVAL);
769
770 /*
771 * Each scope is associated with at least one listener. We need to
772 * traverse that list of listeners, as long as they return either
773 * KAUTH_REQUEST_DEFER or KAUTH_REQUEST_ALLOW.
774 */
775 fail = 0;
776 allow = 0;
777 SIMPLEQ_FOREACH(listener, &scope->listenq, listener_next) {
778 error = listener->func(cred, action, scope->cookie, arg0,
779 arg1, arg2, arg3);
780
781 if (error == KAUTH_RESULT_ALLOW)
782 allow = 1;
783 else if (error == KAUTH_RESULT_DENY)
784 fail = 1;
785 }
786
787 return ((allow && !fail) ? 0 : EPERM);
788 };
789
790 /*
791 * Generic scope default callback.
792 */
793 int
794 kauth_authorize_cb_generic(kauth_cred_t cred, kauth_action_t action,
795 void *cookie, void *arg0, void *arg1, void *arg2,
796 void *arg3)
797 {
798 int error;
799
800 error = KAUTH_RESULT_DEFER;
801
802 switch (action) {
803 case KAUTH_GENERIC_ISSUSER:
804 /* Check if credential belongs to superuser. */
805 if (cred->cr_euid == 0) {
806 u_short *acflag = (u_short *)arg0;
807
808 if (acflag != NULL)
809 *acflag |= ASU;
810
811 error = KAUTH_RESULT_ALLOW;
812 } else
813 error = KAUTH_RESULT_DENY;
814 break;
815 }
816
817 return (error);
818 }
819
820 /*
821 * Generic scope authorization wrapper.
822 */
823 int
824 generic_authorize(kauth_cred_t cred, kauth_action_t action, void *arg0)
825 {
826 return (kauth_authorize_action(builtin_generic, cred, action, arg0,
827 NULL, NULL, NULL));
828 }
829
830 /*
831 * Process scope default callback.
832 */
833 int
834 kauth_authorize_cb_process(kauth_cred_t cred, kauth_action_t action,
835 void *cookie, void *arg0, void *arg1, void *arg2,
836 void *arg3)
837 {
838 struct proc *p;
839 kauth_cred_t cred2;
840 int error;
841
842 error = KAUTH_RESULT_DEFER;
843
844 p = arg0;
845 cred2 = arg1;
846
847 switch (action) {
848 case KAUTH_PROCESS_CANSIGNAL: {
849 struct proc *to;
850 int signum;
851
852 to = arg2;
853 signum = (int)(unsigned long)arg3;
854
855 if ((kauth_cred_uidmatch(cred, cred2) == 0) ||
856 (signum == SIGCONT && (p->p_session == to->p_session)))
857 error = KAUTH_RESULT_ALLOW;
858 else
859 error = KAUTH_RESULT_DEFER;
860
861 break;
862 }
863
864 case KAUTH_PROCESS_CANPTRACE:
865 if (kauth_cred_uidmatch(cred, cred2) == 0)
866 error = KAUTH_RESULT_ALLOW;
867 else
868 error = KAUTH_RESULT_DENY;
869 break;
870
871 case KAUTH_PROCESS_CANSEE:
872 if (kauth_cred_uidmatch(cred, cred2) == 0)
873 error = KAUTH_RESULT_ALLOW;
874 else
875 error = KAUTH_RESULT_DENY;
876 /* arg2 - type of information [XXX NOTIMPL] */
877 break;
878 }
879
880 return (error);
881 }
882