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80594fc2 JJ |
1 | /* |
2 | * AppArmor security module | |
3 | * | |
4 | * This file contains AppArmor label definitions | |
5 | * | |
6 | * Copyright 2013 Canonical Ltd. | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or | |
9 | * modify it under the terms of the GNU General Public License as | |
10 | * published by the Free Software Foundation, version 2 of the | |
11 | * License. | |
12 | */ | |
13 | ||
14 | #include <linux/audit.h> | |
15 | #include <linux/seq_file.h> | |
16 | #include <linux/sort.h> | |
17 | ||
18 | #include "include/apparmor.h" | |
19 | #include "include/context.h" | |
20 | #include "include/label.h" | |
21 | #include "include/policy.h" | |
22 | #include "include/sid.h" | |
23 | ||
24 | ||
25 | /* | |
26 | * the aa_label represents the set of profiles confining an object | |
27 | * | |
28 | * Labels maintain a reference count to the set of pointers they reference | |
29 | * Labels are ref counted by | |
30 | * tasks and object via the security field/security context off the field | |
31 | * code - will take a ref count on a label if it needs the label | |
32 | * beyond what is possible with an rcu_read_lock. | |
33 | * profiles - each profile is a label | |
34 | * sids - a pinned sid will keep a refcount of the label it is | |
35 | * referencing | |
36 | * objects - inode, files, sockets, ... | |
37 | * | |
38 | * Labels are not ref counted by the label set, so they maybe removed and | |
39 | * freed when no longer in use. | |
40 | * | |
41 | */ | |
42 | ||
43 | #define PROXY_POISON 97 | |
44 | #define LABEL_POISON 100 | |
45 | ||
46 | static void free_proxy(struct aa_proxy *proxy) | |
47 | { | |
48 | if (proxy) { | |
49 | /* p->label will not updated any more as p is dead */ | |
50 | aa_put_label(rcu_dereference_protected(proxy->label, true)); | |
51 | memset(proxy, 0, sizeof(*proxy)); | |
52 | proxy->label = (struct aa_label *) PROXY_POISON; | |
53 | kfree(proxy); | |
54 | } | |
55 | } | |
56 | ||
57 | void aa_proxy_kref(struct kref *kref) | |
58 | { | |
59 | struct aa_proxy *proxy = container_of(kref, struct aa_proxy, count); | |
60 | free_proxy(proxy); | |
61 | } | |
62 | ||
63 | struct aa_proxy *aa_alloc_proxy(struct aa_label *label, gfp_t gfp) | |
64 | { | |
65 | struct aa_proxy *new; | |
66 | ||
67 | new = kzalloc(sizeof(struct aa_proxy), gfp); | |
68 | if (new) { | |
69 | kref_init(&new->count); | |
70 | rcu_assign_pointer(new->label, aa_get_label(label)); | |
71 | } | |
72 | return new; | |
73 | } | |
74 | ||
75 | /* requires profile list write lock held */ | |
76 | void __aa_proxy_redirect(struct aa_label *orig, struct aa_label *new) | |
77 | { | |
78 | struct aa_label *tmp; | |
79 | ||
80 | AA_BUG(!orig); | |
81 | AA_BUG(!new); | |
82 | AA_BUG(!write_is_locked(&labels_set(orig)->lock)); | |
83 | ||
84 | tmp = rcu_dereference_protected(orig->proxy->label, | |
85 | &labels_ns(orig)->lock); | |
86 | rcu_assign_pointer(orig->proxy->label, aa_get_label(new)); | |
87 | orig->flags |= FLAG_STALE; | |
88 | aa_put_label(tmp); | |
89 | } | |
90 | ||
91 | static void __proxy_share(struct aa_label *old, struct aa_label *new) | |
92 | { | |
93 | struct aa_proxy *proxy = new->proxy; | |
94 | new->proxy = aa_get_proxy(old->proxy); | |
95 | __aa_proxy_redirect(old, new); | |
96 | aa_put_proxy(proxy); | |
97 | } | |
98 | ||
99 | ||
100 | /** | |
101 | * ns_cmp - compare ns for label set ordering | |
102 | * @a: ns to compare (NOT NULL) | |
103 | * @b: ns to compare (NOT NULL) | |
104 | * | |
105 | * Returns: <0 if a < b | |
106 | * ==0 if a == b | |
107 | * >0 if a > b | |
108 | */ | |
109 | static int ns_cmp(struct aa_ns *a, struct aa_ns *b) | |
110 | { | |
111 | int res; | |
112 | ||
113 | AA_BUG(!a); | |
114 | AA_BUG(!b); | |
fa6e3377 JJ |
115 | AA_BUG(!a->base.hname); |
116 | AA_BUG(!b->base.hname); | |
80594fc2 JJ |
117 | |
118 | if (a == b) | |
119 | return 0; | |
120 | ||
121 | res = a->level - b->level; | |
122 | if (res) | |
123 | return res; | |
124 | ||
fa6e3377 | 125 | return strcmp(a->base.hname, b->base.hname); |
80594fc2 JJ |
126 | } |
127 | ||
128 | /** | |
129 | * profile_cmp - profile comparision for set ordering | |
130 | * @a: profile to compare (NOT NULL) | |
131 | * @b: profile to compare (NOT NULL) | |
132 | * | |
133 | * Returns: <0 if a < b | |
134 | * ==0 if a == b | |
135 | * >0 if a > b | |
136 | */ | |
137 | static int profile_cmp(struct aa_profile *a, struct aa_profile *b) | |
138 | { | |
139 | int res; | |
140 | ||
141 | AA_BUG(!a); | |
142 | AA_BUG(!b); | |
143 | AA_BUG(!a->ns); | |
144 | AA_BUG(!b->ns); | |
145 | AA_BUG(!a->base.hname); | |
146 | AA_BUG(!b->base.hname); | |
147 | ||
148 | if (a == b || a->base.hname == b->base.hname) | |
149 | return 0; | |
150 | res = ns_cmp(a->ns, b->ns); | |
151 | if (res) | |
152 | return res; | |
153 | ||
154 | return strcmp(a->base.hname, b->base.hname); | |
155 | } | |
156 | ||
157 | /** | |
158 | * vec_cmp - label comparision for set ordering | |
159 | * @a: label to compare (NOT NULL) | |
160 | * @vec: vector of profiles to compare (NOT NULL) | |
161 | * @n: length of @vec | |
162 | * | |
163 | * Returns: <0 if a < vec | |
164 | * ==0 if a == vec | |
165 | * >0 if a > vec | |
166 | */ | |
167 | static int vec_cmp(struct aa_profile **a, int an, struct aa_profile **b, int bn) | |
168 | { | |
169 | int i; | |
170 | ||
171 | AA_BUG(!a); | |
172 | AA_BUG(!*a); | |
173 | AA_BUG(!b); | |
174 | AA_BUG(!*b); | |
175 | AA_BUG(an <= 0); | |
176 | AA_BUG(bn <= 0); | |
177 | ||
178 | for (i = 0; i < an && i < bn; i++) { | |
179 | int res = profile_cmp(a[i], b[i]); | |
180 | if (res != 0) | |
181 | return res; | |
182 | } | |
183 | ||
184 | return an - bn; | |
185 | } | |
186 | ||
187 | static bool vec_is_stale(struct aa_profile **vec, int n) | |
188 | { | |
189 | int i; | |
190 | ||
191 | AA_BUG(!vec); | |
192 | ||
193 | for (i = 0; i < n; i++) { | |
194 | if (profile_is_stale(vec[i])) | |
195 | return true; | |
196 | } | |
197 | ||
198 | return false; | |
199 | } | |
200 | ||
201 | static bool vec_unconfined(struct aa_profile **vec, int n) | |
202 | { | |
203 | int i; | |
204 | ||
205 | AA_BUG(!vec); | |
206 | ||
207 | for (i = 0; i < n; i++) { | |
208 | if (!profile_unconfined(vec[i])) | |
209 | return false; | |
210 | } | |
211 | ||
212 | return true; | |
213 | } | |
214 | ||
215 | static int sort_cmp(const void *a, const void *b) | |
216 | { | |
217 | return profile_cmp(*(struct aa_profile **)a, *(struct aa_profile **)b); | |
218 | } | |
219 | ||
220 | /* assumes vec is sorted | |
221 | * Assumes @vec has null terminator at vec[n], and will null terminate | |
222 | * vec[n - dups] | |
223 | */ | |
224 | static inline int unique(struct aa_profile **vec, int n) | |
225 | { | |
226 | int i, pos, dups = 0; | |
227 | ||
228 | AA_BUG(n < 1); | |
229 | AA_BUG(!vec); | |
230 | ||
231 | pos = 0; | |
c7b3b195 | 232 | for (i = 1; i < n; i++) { |
80594fc2 JJ |
233 | int res = profile_cmp(vec[pos], vec[i]); |
234 | AA_BUG(res > 0, "vec not sorted"); | |
235 | if (res == 0) { | |
236 | /* drop duplicate */ | |
237 | aa_put_profile(vec[i]); | |
238 | dups++; | |
239 | continue; | |
240 | } | |
241 | pos++; | |
242 | if (dups) | |
243 | vec[pos] = vec[i]; | |
244 | } | |
245 | ||
246 | AA_BUG(dups < 0); | |
247 | ||
248 | return dups; | |
249 | } | |
250 | ||
251 | /** | |
252 | * vec_unique - canonical sort and unique a list of profiles | |
253 | * @n: number of refcounted profiles in the list (@n > 0) | |
254 | * @vec: list of profiles to sort and merge | |
255 | * | |
256 | * Returns: the number of duplicates eliminated == references put | |
257 | * | |
258 | * If @flags & VEC_FLAG_TERMINATE @vec has null terminator at vec[n], and will | |
259 | * null terminate vec[n - dups] | |
260 | */ | |
261 | int aa_vec_unique(struct aa_profile **vec, int n, int flags) | |
262 | { | |
263 | int i, dups = 0; | |
264 | ||
265 | AA_BUG(n < 1); | |
266 | AA_BUG(!vec); | |
267 | ||
268 | /* vecs are usually small and inorder, have a fallback for larger */ | |
269 | if (n > 8) { | |
270 | sort(vec, n, sizeof(struct aa_profile *), sort_cmp, NULL); | |
271 | dups = unique(vec, n); | |
272 | goto out; | |
273 | } | |
274 | ||
275 | /* insertion sort + unique in one */ | |
276 | for (i = 1; i < n; i++) { | |
277 | struct aa_profile *tmp = vec[i]; | |
278 | int pos, j; | |
279 | ||
280 | for (pos = i - 1 - dups; pos >= 0; pos--) { | |
281 | int res = profile_cmp(vec[pos], tmp); | |
282 | if (res == 0) { | |
283 | /* drop duplicate entry */ | |
284 | aa_put_profile(tmp); | |
285 | dups++; | |
286 | goto continue_outer; | |
287 | } else if (res < 0) | |
288 | break; | |
289 | } | |
290 | /* pos is at entry < tmp, or index -1. Set to insert pos */ | |
291 | pos++; | |
292 | ||
293 | for (j = i - dups; j > pos; j--) | |
294 | vec[j] = vec[j - 1]; | |
295 | vec[pos] = tmp; | |
296 | continue_outer: ; | |
297 | } | |
298 | ||
299 | AA_BUG(dups < 0); | |
300 | ||
301 | out: | |
302 | if (flags & VEC_FLAG_TERMINATE) | |
303 | vec[n - dups] = NULL; | |
304 | ||
305 | return dups; | |
306 | } | |
307 | ||
308 | ||
309 | static void label_destroy(struct aa_label *label) | |
310 | { | |
a8b02048 JJ |
311 | struct aa_label *tmp; |
312 | ||
80594fc2 JJ |
313 | AA_BUG(!label); |
314 | ||
315 | if (label_is_stale(label)) | |
316 | labelsetstats_dec(labels_set(label), stale); | |
317 | ||
318 | if (!label_isprofile(label)) { | |
319 | struct aa_profile *profile; | |
320 | struct label_it i; | |
321 | ||
322 | aa_put_str(label->hname); | |
323 | ||
324 | label_for_each(i, label, profile) { | |
325 | aa_put_profile(profile); | |
326 | label->vec[i.i] = (struct aa_profile *) (LABEL_POISON + (long) i.i); | |
327 | } | |
328 | } | |
329 | ||
330 | if (rcu_dereference_protected(label->proxy->label, true) == label) | |
331 | rcu_assign_pointer(label->proxy->label, NULL); | |
332 | ||
333 | aa_free_sid(label->sid); | |
a8b02048 JJ |
334 | |
335 | tmp = rcu_dereference_protected(label->proxy->label, true); | |
336 | if (tmp == label) | |
337 | rcu_assign_pointer(label->proxy->label, NULL); | |
338 | ||
80594fc2 JJ |
339 | aa_put_proxy(label->proxy); |
340 | label->proxy = (struct aa_proxy *) PROXY_POISON + 1; | |
341 | } | |
342 | ||
343 | void aa_label_free(struct aa_label *label) | |
344 | { | |
345 | if (!label) | |
346 | return; | |
347 | ||
348 | label_destroy(label); | |
349 | labelstats_inc(freed); | |
350 | kfree(label); | |
351 | } | |
352 | ||
353 | static void label_free_switch(struct aa_label *label) | |
354 | { | |
355 | if (label->flags & FLAG_NS_COUNT) | |
356 | aa_free_ns(labels_ns(label)); | |
357 | else if (label_isprofile(label)) | |
358 | aa_free_profile(labels_profile(label)); | |
359 | else | |
360 | aa_label_free(label); | |
361 | } | |
362 | ||
363 | static void label_free_rcu(struct rcu_head *head) | |
364 | { | |
365 | struct aa_label *label = container_of(head, struct aa_label, rcu); | |
366 | ||
367 | if (label->flags & FLAG_IN_TREE) | |
368 | (void) aa_label_remove(label); | |
369 | label_free_switch(label); | |
370 | } | |
371 | ||
372 | void aa_label_kref(struct kref *kref) | |
373 | { | |
374 | struct aa_label *label = container_of(kref, struct aa_label, count); | |
375 | struct aa_ns *ns = labels_ns(label); | |
376 | ||
377 | if (!ns) { | |
378 | /* never live, no rcu callback needed, just using the fn */ | |
379 | label_free_switch(label); | |
380 | return; | |
381 | } | |
382 | /* TODO: update labels_profile macro so it works here */ | |
383 | AA_BUG(label_isprofile(label) && on_list_rcu(&label->vec[0]->base.profiles)); | |
384 | AA_BUG(label_isprofile(label) && on_list_rcu(&label->vec[0]->base.list)); | |
385 | ||
386 | /* TODO: if compound label and not stale add to reclaim cache */ | |
387 | call_rcu(&label->rcu, label_free_rcu); | |
388 | } | |
389 | ||
a8b02048 JJ |
390 | static void label_free_or_put_new(struct aa_label *label, struct aa_label *new) |
391 | { | |
392 | if (label != new) | |
393 | /* need to free directly to break circular ref with proxy */ | |
394 | aa_label_free(new); | |
395 | else | |
396 | aa_put_label(new); | |
397 | } | |
398 | ||
80594fc2 JJ |
399 | bool aa_label_init(struct aa_label *label, int size) |
400 | { | |
401 | AA_BUG(!label); | |
402 | AA_BUG(size < 1); | |
403 | ||
404 | label->sid = aa_alloc_sid(); | |
405 | if (label->sid == AA_SID_INVALID) | |
406 | return false; | |
407 | ||
408 | label->size = size; /* doesn't include null */ | |
409 | label->vec[size] = NULL; /* null terminate */ | |
410 | kref_init(&label->count); | |
411 | RB_CLEAR_NODE(&label->node); | |
412 | ||
413 | return true; | |
414 | } | |
415 | ||
416 | /** | |
417 | * aa_label_alloc - allocate a label with a profile vector of @size length | |
418 | * @size: size of profile vector in the label | |
419 | * @proxy: proxy to use OR null if to allocate a new one | |
420 | * @gfp: memory allocation type | |
421 | * | |
422 | * Returns: new label | |
423 | * else NULL if failed | |
424 | */ | |
425 | struct aa_label *aa_label_alloc(int size, struct aa_proxy *proxy, gfp_t gfp) | |
426 | { | |
427 | struct aa_label *new; | |
428 | ||
429 | AA_BUG(size < 1); | |
430 | ||
431 | /* + 1 for null terminator entry on vec */ | |
432 | new = kzalloc(sizeof(*new) + sizeof(struct aa_profile *) * (size + 1), | |
433 | gfp); | |
434 | AA_DEBUG("%s (%p)\n", __func__, new); | |
435 | if (!new) | |
436 | goto fail; | |
437 | ||
438 | if (!aa_label_init(new, size)) | |
439 | goto fail; | |
440 | ||
441 | if (!proxy) { | |
442 | proxy = aa_alloc_proxy(new, gfp); | |
443 | if (!proxy) | |
444 | goto fail; | |
445 | } else | |
446 | aa_get_proxy(proxy); | |
447 | /* just set new's proxy, don't redirect proxy here if it was passed in*/ | |
448 | new->proxy = proxy; | |
449 | ||
450 | labelstats_inc(allocated); | |
451 | ||
452 | return new; | |
453 | ||
454 | fail: | |
455 | kfree(new); | |
456 | labelstats_inc(failed); | |
457 | ||
458 | return NULL; | |
459 | } | |
460 | ||
461 | ||
462 | /** | |
463 | * label_cmp - label comparision for set ordering | |
464 | * @a: label to compare (NOT NULL) | |
465 | * @b: label to compare (NOT NULL) | |
466 | * | |
467 | * Returns: <0 if a < b | |
468 | * ==0 if a == b | |
469 | * >0 if a > b | |
470 | */ | |
471 | static int label_cmp(struct aa_label *a, struct aa_label *b) | |
472 | { | |
473 | AA_BUG(!b); | |
474 | ||
475 | if (a == b) | |
476 | return 0; | |
477 | ||
478 | return vec_cmp(a->vec, a->size, b->vec, b->size); | |
479 | } | |
480 | ||
481 | /* helper fn for label_for_each_confined */ | |
482 | int aa_label_next_confined(struct aa_label *label, int i) | |
483 | { | |
484 | AA_BUG(!label); | |
485 | AA_BUG(i < 0); | |
486 | ||
487 | for (; i < label->size; i++) { | |
488 | if (!profile_unconfined(label->vec[i])) | |
489 | return i; | |
490 | } | |
491 | ||
492 | return i; | |
493 | } | |
494 | ||
495 | /** | |
496 | * aa_label_next_not_in_set - return the next profile of @sub not in @set | |
497 | * @I: label iterator | |
498 | * @set: label to test against | |
499 | * @sub: label to if is subset of @set | |
500 | * | |
501 | * Returns: profile in @sub that is not in @set, with iterator set pos after | |
502 | * else NULL if @sub is a subset of @set | |
503 | */ | |
504 | struct aa_profile *__aa_label_next_not_in_set(struct label_it *I, | |
505 | struct aa_label *set, | |
506 | struct aa_label *sub) | |
507 | { | |
508 | AA_BUG(!set); | |
509 | AA_BUG(!I); | |
510 | AA_BUG(I->i < 0); | |
511 | AA_BUG(I->i > set->size); | |
512 | AA_BUG(!sub); | |
513 | AA_BUG(I->j < 0); | |
514 | AA_BUG(I->j > sub->size); | |
515 | ||
516 | while (I->j < sub->size && I->i < set->size) { | |
517 | int res = profile_cmp(sub->vec[I->j], set->vec[I->i]); | |
518 | if (res == 0) { | |
519 | (I->j)++; | |
520 | (I->i)++; | |
521 | } else if (res > 0) | |
522 | (I->i)++; | |
523 | else | |
524 | return sub->vec[(I->j)++]; | |
525 | } | |
526 | ||
527 | if (I->j < sub->size) | |
528 | return sub->vec[(I->j)++]; | |
529 | ||
530 | return NULL; | |
531 | } | |
532 | ||
533 | /** | |
534 | * aa_label_is_subset - test if @sub is a subset of @set | |
535 | * @set: label to test against | |
536 | * @sub: label to test if is subset of @set | |
537 | * | |
538 | * Returns: true if @sub is subset of @set | |
539 | * else false | |
540 | */ | |
541 | bool aa_label_is_subset(struct aa_label *set, struct aa_label *sub) | |
542 | { | |
543 | struct label_it i = { }; | |
544 | ||
545 | AA_BUG(!set); | |
546 | AA_BUG(!sub); | |
547 | ||
548 | if (sub == set) | |
549 | return true; | |
550 | ||
551 | return __aa_label_next_not_in_set(&i, set, sub) == NULL; | |
552 | } | |
553 | ||
554 | ||
555 | ||
556 | /** | |
557 | * __label_remove - remove @label from the label set | |
558 | * @l: label to remove | |
559 | * @new: label to redirect to | |
560 | * | |
561 | * Requires: labels_set(@label)->lock write_lock | |
562 | * Returns: true if the label was in the tree and removed | |
563 | */ | |
564 | static bool __label_remove(struct aa_label *label, struct aa_label *new) | |
565 | { | |
566 | struct aa_labelset *ls = labels_set(label); | |
567 | AA_BUG(!ls); | |
568 | AA_BUG(!label); | |
569 | AA_BUG(!write_is_locked(&ls->lock)); | |
570 | ||
571 | if (new) | |
572 | __aa_proxy_redirect(label, new); | |
573 | ||
574 | if (label_is_stale(label)) | |
575 | labelstats_dec(stale_intree); | |
576 | else | |
577 | __label_make_stale(label); | |
578 | ||
579 | if (label->flags & FLAG_IN_TREE) { | |
580 | labelsetstats_dec(ls, intree); | |
581 | rb_erase(&label->node, &ls->root); | |
582 | label->flags &= ~FLAG_IN_TREE; | |
583 | return true; | |
584 | } | |
585 | ||
586 | return false; | |
587 | } | |
588 | ||
589 | /** | |
590 | * __label_replace - replace @old with @new in label set | |
591 | * @old: label to remove from label set | |
592 | * @new: label to replace @old with | |
593 | * | |
594 | * Requires: labels_set(@old)->lock write_lock | |
595 | * valid ref count be held on @new | |
596 | * Returns: true if @old was in set and replaced by @new | |
597 | * | |
598 | * Note: current implementation requires label set be order in such a way | |
599 | * that @new directly replaces @old position in the set (ie. | |
600 | * using pointer comparison of the label address would not work) | |
601 | */ | |
602 | static bool __label_replace(struct aa_label *old, struct aa_label *new) | |
603 | { | |
604 | struct aa_labelset *ls = labels_set(old); | |
605 | AA_BUG(!ls); | |
606 | AA_BUG(!old); | |
607 | AA_BUG(!new); | |
608 | AA_BUG(!write_is_locked(&ls->lock)); | |
609 | AA_BUG(new->flags & FLAG_IN_TREE); | |
610 | ||
611 | if (label_is_stale(old)) | |
612 | labelstats_dec(stale_intree); | |
613 | else | |
614 | __label_make_stale(old); | |
615 | ||
616 | if (old->flags & FLAG_IN_TREE) { | |
617 | rb_replace_node(&old->node, &new->node, &ls->root); | |
618 | old->flags &= ~FLAG_IN_TREE; | |
619 | new->flags |= FLAG_IN_TREE; | |
620 | return true; | |
621 | } | |
622 | ||
623 | return false; | |
624 | } | |
625 | ||
626 | /** | |
627 | * __label_insert - attempt to insert @l into a label set | |
628 | * @ls: set of labels to insert @l into (NOT NULL) | |
629 | * @label: new label to insert (NOT NULL) | |
630 | * @replace: whether insertion should replace existing entry that is not stale | |
631 | * | |
632 | * Requires: @ls->lock | |
633 | * caller to hold a valid ref on l | |
634 | * if @replace is true l has a preallocated proxy associated | |
635 | * Returns: @l if successful in inserting @l - with additional refcount | |
636 | * else ref counted equivalent label that is already in the set, | |
637 | the else condition only happens if @replace is false | |
638 | */ | |
639 | static struct aa_label *__label_insert(struct aa_labelset *ls, | |
640 | struct aa_label *label, bool replace) | |
641 | { | |
642 | struct rb_node **new, *parent = NULL; | |
643 | ||
644 | AA_BUG(!ls); | |
645 | AA_BUG(!label); | |
646 | AA_BUG(labels_set(label) != ls); | |
647 | AA_BUG(!write_is_locked(&ls->lock)); | |
648 | AA_BUG(label->flags & FLAG_IN_TREE); | |
649 | ||
650 | /* Figure out where to put new node */ | |
651 | new = &ls->root.rb_node; | |
652 | while (*new) { | |
653 | struct aa_label *this = rb_entry(*new, struct aa_label, node); | |
654 | int result = label_cmp(label, this); | |
655 | ||
656 | parent = *new; | |
657 | if (result == 0) { | |
658 | labelsetstats_inc(ls, existing); | |
659 | /* !aa_get_label_not0 means queued for destruction, | |
660 | * so replace in place, however the label has | |
661 | * died before the replacement so do not share | |
662 | * the proxy | |
663 | */ | |
664 | if (!replace && !label_is_stale(this)) { | |
665 | if (aa_get_label_not0(this)) | |
666 | return this; | |
667 | } else | |
668 | __proxy_share(this, label); | |
669 | AA_BUG(!__label_replace(this, label)); | |
670 | return aa_get_label(label); | |
671 | } else if (result < 0) | |
672 | new = &((*new)->rb_left); | |
673 | else /* (result > 0) */ | |
674 | new = &((*new)->rb_right); | |
675 | } | |
676 | ||
677 | /* Add new node and rebalance tree. */ | |
678 | rb_link_node(&label->node, parent, new); | |
679 | rb_insert_color(&label->node, &ls->root); | |
680 | label->flags |= FLAG_IN_TREE; | |
681 | labelsetstats_inc(ls, insert); | |
682 | labelsetstats_inc(ls, intree); | |
683 | ||
684 | return aa_get_label(label); | |
685 | } | |
686 | ||
687 | /** | |
688 | * __vec_find - find label that matches @vec in label set | |
689 | * @vec: vec of profiles to find matching label for (NOT NULL) | |
690 | * @n: length of @vec | |
691 | * | |
692 | * Requires: @vec_labelset(vec) lock held | |
693 | * caller to hold a valid ref on l | |
694 | * | |
695 | * Returns: ref counted @label if matching label is in tree | |
696 | * ref counted label that is equiv to @l in tree | |
697 | * else NULL if @vec equiv is not in tree | |
698 | */ | |
699 | static struct aa_label *__vec_find(struct aa_profile **vec, int n) | |
700 | { | |
701 | struct rb_node *node; | |
702 | ||
703 | AA_BUG(!vec); | |
704 | AA_BUG(!*vec); | |
705 | AA_BUG(n <= 0); | |
706 | ||
707 | node = vec_labelset(vec, n)->root.rb_node; | |
708 | while (node) { | |
709 | struct aa_label *this = rb_entry(node, struct aa_label, node); | |
710 | int result = vec_cmp(this->vec, this->size, vec, n); | |
711 | ||
712 | if (result > 0) | |
713 | node = node->rb_left; | |
714 | else if (result < 0) | |
715 | node = node->rb_right; | |
716 | else | |
717 | return aa_get_label_not0(this); | |
718 | } | |
719 | ||
720 | return NULL; | |
721 | } | |
722 | ||
723 | /** | |
724 | * __label_find - find label @label in label set | |
725 | * @label: label to find (NOT NULL) | |
726 | * | |
727 | * Requires: labels_set(@label)->lock held | |
728 | * caller to hold a valid ref on l | |
729 | * | |
730 | * Returns: ref counted @label if @label is in tree OR | |
731 | * ref counted label that is equiv to @label in tree | |
732 | * else NULL if @label or equiv is not in tree | |
733 | */ | |
734 | static struct aa_label *__label_find(struct aa_label *label) | |
735 | { | |
736 | AA_BUG(!label); | |
737 | ||
738 | return __vec_find(label->vec, label->size); | |
739 | } | |
740 | ||
741 | ||
742 | /** | |
743 | * aa_label_remove - remove a label from the labelset | |
744 | * @label: label to remove | |
745 | * | |
746 | * Returns: true if @label was removed from the tree | |
747 | * else @label was not in tree so it could not be removed | |
748 | */ | |
749 | bool aa_label_remove(struct aa_label *label) | |
750 | { | |
751 | struct aa_labelset *ls = labels_set(label); | |
752 | unsigned long flags; | |
753 | bool res; | |
754 | ||
755 | AA_BUG(!ls); | |
756 | ||
757 | write_lock_irqsave(&ls->lock, flags); | |
758 | res = __label_remove(label, ns_unconfined(labels_ns(label))); | |
759 | write_unlock_irqrestore(&ls->lock, flags); | |
760 | ||
761 | return res; | |
762 | } | |
763 | ||
764 | /** | |
765 | * aa_label_replace - replace a label @old with a new version @new | |
766 | * @old: label to replace | |
767 | * @new: label replacing @old | |
768 | * | |
769 | * Returns: true if @old was in tree and replaced | |
770 | * else @old was not in tree, and @new was not inserted | |
771 | */ | |
772 | bool aa_label_replace(struct aa_label *old, struct aa_label *new) | |
773 | { | |
774 | unsigned long flags; | |
775 | bool res; | |
776 | ||
777 | if (name_is_shared(old, new) && labels_ns(old) == labels_ns(new)) { | |
778 | write_lock_irqsave(&labels_set(old)->lock, flags); | |
779 | if (old->proxy != new->proxy) { | |
780 | __proxy_share(old, new); | |
781 | } else | |
782 | __aa_proxy_redirect(old, new); | |
783 | res = __label_replace(old, new); | |
784 | write_unlock_irqrestore(&labels_set(old)->lock, flags); | |
785 | } else { | |
786 | struct aa_label *l; | |
787 | struct aa_labelset *ls = labels_set(old); | |
788 | write_lock_irqsave(&ls->lock, flags); | |
789 | res = __label_remove(old, new); | |
790 | if (labels_ns(old) != labels_ns(new)) { | |
791 | write_unlock_irqrestore(&ls->lock, flags); | |
792 | ls = labels_set(new); | |
793 | write_lock_irqsave(&ls->lock, flags); | |
794 | } | |
795 | l = __label_insert(ls, new, true); | |
796 | res = (l == new); | |
797 | write_unlock_irqrestore(&ls->lock, flags); | |
798 | aa_put_label(l); | |
799 | } | |
800 | ||
801 | return res; | |
802 | } | |
803 | ||
804 | /** | |
805 | * vec_find - find label @l in label set | |
806 | * @vec: array of profiles to find equiv label for (NOT NULL) | |
807 | * @n: length of @vec | |
808 | * | |
809 | * Returns: refcounted label if @vec equiv is in tree | |
810 | * else NULL if @vec equiv is not in tree | |
811 | */ | |
812 | static struct aa_label *vec_find(struct aa_profile **vec, int n) | |
813 | { | |
814 | struct aa_labelset *ls; | |
815 | struct aa_label *label; | |
816 | unsigned long flags; | |
817 | ||
818 | AA_BUG(!vec); | |
819 | AA_BUG(!*vec); | |
820 | AA_BUG(n <= 0); | |
821 | ||
822 | ls = vec_labelset(vec, n); | |
823 | read_lock_irqsave(&ls->lock, flags); | |
824 | label = __vec_find(vec, n); | |
825 | labelstats_inc(sread); | |
826 | read_unlock_irqrestore(&ls->lock, flags); | |
827 | ||
828 | return label; | |
829 | } | |
830 | ||
831 | /* requires sort and merge done first */ | |
832 | static struct aa_label *vec_create_and_insert_label(struct aa_profile **vec, | |
833 | int len, gfp_t gfp) | |
834 | { | |
835 | struct aa_label *label = NULL; | |
836 | struct aa_labelset *ls; | |
837 | unsigned long flags; | |
838 | struct aa_label *new; | |
839 | int i; | |
840 | ||
841 | AA_BUG(!vec); | |
842 | ||
843 | if (len == 1) | |
844 | return aa_get_label(&vec[0]->label); | |
845 | ||
846 | ls = labels_set(&vec[len - 1]->label); | |
847 | ||
848 | /* TODO: enable when read side is lockless | |
849 | * check if label exists before taking locks | |
850 | */ | |
851 | new = aa_label_alloc(len, NULL, gfp); | |
852 | if (!new) | |
853 | return NULL; | |
854 | ||
855 | for (i = 0; i < len; i++) { | |
856 | new->vec[i] = aa_get_profile(vec[i]); | |
857 | } | |
858 | write_lock_irqsave(&ls->lock, flags); | |
859 | label = __label_insert(ls, new, false); | |
860 | write_unlock_irqrestore(&ls->lock, flags); | |
a8b02048 | 861 | label_free_or_put_new(label, new); |
80594fc2 JJ |
862 | |
863 | return label; | |
864 | } | |
865 | ||
866 | struct aa_label *aa_vec_find_or_create_label(struct aa_profile **vec, int len, | |
867 | gfp_t gfp) | |
868 | { | |
869 | struct aa_label *label = vec_find(vec, len); | |
870 | if (label) | |
871 | return label; | |
872 | ||
873 | return vec_create_and_insert_label(vec, len, gfp); | |
874 | } | |
875 | ||
876 | /** | |
877 | * aa_label_find - find label @label in label set | |
878 | * @label: label to find (NOT NULL) | |
879 | * | |
880 | * Requires: caller to hold a valid ref on l | |
881 | * | |
882 | * Returns: refcounted @label if @label is in tree | |
883 | * refcounted label that is equiv to @label in tree | |
884 | * else NULL if @label or equiv is not in tree | |
885 | */ | |
886 | struct aa_label *aa_label_find(struct aa_label *label) | |
887 | { | |
888 | AA_BUG(!label); | |
889 | ||
890 | return vec_find(label->vec, label->size); | |
891 | } | |
892 | ||
893 | ||
894 | /** | |
895 | * aa_label_insert - insert label @label into @ls or return existing label | |
896 | * @ls - labelset to insert @label into | |
897 | * @label - label to insert | |
898 | * | |
899 | * Requires: caller to hold a valid ref on @label | |
900 | * | |
901 | * Returns: ref counted @label if successful in inserting @label | |
902 | * else ref counted equivalent label that is already in the set | |
903 | */ | |
904 | struct aa_label *aa_label_insert(struct aa_labelset *ls, struct aa_label *label) | |
905 | { | |
906 | struct aa_label *l; | |
907 | unsigned long flags; | |
908 | ||
909 | AA_BUG(!ls); | |
910 | AA_BUG(!label); | |
911 | ||
912 | /* check if label exists before taking lock */ | |
913 | if (!label_is_stale(label)) { | |
914 | read_lock_irqsave(&ls->lock, flags); | |
915 | l = __label_find(label); | |
916 | read_unlock_irqrestore(&ls->lock, flags); | |
917 | labelstats_inc(fread); | |
918 | if (l) | |
919 | return l; | |
920 | } | |
921 | ||
922 | write_lock_irqsave(&ls->lock, flags); | |
923 | l = __label_insert(ls, label, false); | |
924 | write_unlock_irqrestore(&ls->lock, flags); | |
925 | ||
926 | return l; | |
927 | } | |
928 | ||
929 | ||
930 | /** | |
931 | * aa_label_next_in_merge - find the next profile when merging @a and @b | |
932 | * @I: label iterator | |
933 | * @a: label to merge | |
934 | * @b: label to merge | |
935 | * | |
936 | * Returns: next profile | |
937 | * else null if no more profiles | |
938 | */ | |
939 | struct aa_profile *aa_label_next_in_merge(struct label_it *I, | |
940 | struct aa_label *a, | |
941 | struct aa_label *b) | |
942 | { | |
943 | AA_BUG(!a); | |
944 | AA_BUG(!b); | |
945 | AA_BUG(!I); | |
946 | AA_BUG(I->i < 0); | |
947 | AA_BUG(I->i > a->size); | |
948 | AA_BUG(I->j < 0); | |
949 | AA_BUG(I->j > b->size); | |
950 | ||
951 | if (I->i < a->size) { | |
952 | if (I->j < b->size) { | |
953 | int res = profile_cmp(a->vec[I->i], b->vec[I->j]); | |
954 | if (res > 0) | |
955 | return b->vec[(I->j)++]; | |
956 | if (res == 0) | |
957 | (I->j)++; | |
958 | } | |
959 | ||
960 | return a->vec[(I->i)++]; | |
961 | } | |
962 | ||
963 | if (I->j < b->size) | |
964 | return b->vec[(I->j)++]; | |
965 | ||
966 | return NULL; | |
967 | } | |
968 | ||
969 | /** | |
970 | * label_merge_cmp - cmp of @a merging with @b against @z for set ordering | |
971 | * @a: label to merge then compare (NOT NULL) | |
972 | * @b: label to merge then compare (NOT NULL) | |
973 | * @z: label to compare merge against (NOT NULL) | |
974 | * | |
975 | * Assumes: using the most recent versions of @a, @b, and @z | |
976 | * | |
977 | * Returns: <0 if a < b | |
978 | * ==0 if a == b | |
979 | * >0 if a > b | |
980 | */ | |
981 | static int label_merge_cmp(struct aa_label *a, struct aa_label *b, | |
982 | struct aa_label *z) | |
983 | { | |
984 | struct aa_profile *p = NULL; | |
985 | struct label_it i = { }; | |
986 | int k; | |
987 | ||
988 | AA_BUG(!a); | |
989 | AA_BUG(!b); | |
990 | AA_BUG(!z); | |
991 | ||
992 | for (k = 0; | |
993 | k < z->size && (p = aa_label_next_in_merge(&i, a, b)); | |
994 | k++) { | |
995 | int res = profile_cmp(p, z->vec[k]); | |
996 | ||
997 | if (res != 0) | |
998 | return res; | |
999 | } | |
1000 | ||
1001 | if (p) | |
1002 | return 1; | |
1003 | else if (k < z->size) | |
1004 | return -1; | |
1005 | return 0; | |
1006 | } | |
1007 | ||
1008 | #if 0 | |
1009 | /** | |
1010 | * label_merge_len - find the length of the merge of @a and @b | |
1011 | * @a: label to merge (NOT NULL) | |
1012 | * @b: label to merge (NOT NULL) | |
1013 | * | |
1014 | * Assumes: using newest versions of labels @a and @b | |
1015 | * | |
1016 | * Returns: length of a label vector for merge of @a and @b | |
1017 | */ | |
1018 | static int label_merge_len(struct aa_label *a, struct aa_label *b) | |
1019 | { | |
1020 | int len = a->size + b->size; | |
1021 | int i, j; | |
1022 | ||
1023 | AA_BUG(!a); | |
1024 | AA_BUG(!b); | |
1025 | ||
1026 | /* find entries in common and remove from count */ | |
1027 | for (i = j = 0; i < a->size && j < b->size; ) { | |
1028 | int res = profile_cmp(a->vec[i], b->vec[j]); | |
1029 | if (res == 0) { | |
1030 | len--; | |
1031 | i++; | |
1032 | j++; | |
1033 | } else if (res < 0) | |
1034 | i++; | |
1035 | else | |
1036 | j++; | |
1037 | } | |
1038 | ||
1039 | return len; | |
1040 | } | |
1041 | #endif | |
1042 | ||
1043 | /** | |
1044 | * label_merge_insert - create a new label by merging @a and @b | |
1045 | * @new: preallocated label to merge into (NOT NULL) | |
1046 | * @a: label to merge with @b (NOT NULL) | |
1047 | * @b: label to merge with @a (NOT NULL) | |
1048 | * | |
1049 | * Requires: preallocated proxy | |
1050 | * | |
1051 | * Returns: ref counted label either @new if merge is unique | |
1052 | * @a if @b is a subset of @a | |
1053 | * @b if @a is a subset of @b | |
1054 | * | |
1055 | * NOTE: will not use @new if the merge results in @new == @a or @b | |
1056 | * | |
1057 | * Must be used within labelset write lock to avoid racing with | |
1058 | * setting labels stale. | |
1059 | */ | |
1060 | static struct aa_label *label_merge_insert(struct aa_label *new, | |
1061 | struct aa_label *a, | |
1062 | struct aa_label *b) | |
1063 | { | |
1064 | struct aa_label *label; | |
1065 | struct aa_labelset *ls; | |
1066 | struct aa_profile *next; | |
1067 | struct label_it i; | |
1068 | unsigned long flags; | |
1069 | int k = 0, invcount = 0; | |
1070 | bool stale = false; | |
1071 | ||
1072 | AA_BUG(!a); | |
1073 | AA_BUG(a->size < 0); | |
1074 | AA_BUG(!b); | |
1075 | AA_BUG(b->size < 0); | |
1076 | AA_BUG(!new); | |
1077 | AA_BUG(new->size < a->size + b->size); | |
1078 | ||
1079 | label_for_each_in_merge(i, a, b, next) { | |
bfa31064 | 1080 | AA_BUG(!next); |
80594fc2 JJ |
1081 | if (profile_is_stale(next)) { |
1082 | new->vec[k] = aa_get_newest_profile(next); | |
bfa31064 JJ |
1083 | AA_BUG(!new->vec[k]->label.proxy); |
1084 | AA_BUG(!new->vec[k]->label.proxy->label); | |
80594fc2 JJ |
1085 | if (next->label.proxy != new->vec[k]->label.proxy) |
1086 | invcount++; | |
1087 | k++; | |
1088 | stale = true; | |
1089 | } else | |
1090 | new->vec[k++] = aa_get_profile(next); | |
1091 | } | |
1092 | /* set to actual size which is <= allocated len */ | |
1093 | new->size = k; | |
1094 | new->vec[k] = NULL; | |
1095 | ||
1096 | if (invcount) { | |
1097 | new->size -= aa_vec_unique(&new->vec[0], new->size, | |
1098 | VEC_FLAG_TERMINATE); | |
6c96ac34 JJ |
1099 | /* TODO: deal with reference labels */ |
1100 | if (new->size == 1) { | |
1101 | label = aa_get_label(&new->vec[0]->label); | |
6c96ac34 JJ |
1102 | return label; |
1103 | } | |
80594fc2 JJ |
1104 | } else if (!stale) { |
1105 | /* merge could be same as a || b, note: it is not possible | |
1106 | * for new->size == a->size == b->size unless a == b */ | |
1107 | if (k == a->size) | |
1108 | return aa_get_label(a); | |
1109 | else if (k == b->size) | |
1110 | return aa_get_label(b); | |
1111 | } | |
1112 | if (vec_unconfined(new->vec, new->size)) | |
1113 | new->flags |= FLAG_UNCONFINED; | |
1114 | ls = labels_set(new); | |
1115 | write_lock_irqsave(&ls->lock, flags); | |
1116 | label = __label_insert(labels_set(new), new, false); | |
1117 | write_unlock_irqrestore(&ls->lock, flags); | |
1118 | ||
1119 | return label; | |
1120 | } | |
1121 | ||
1122 | /** | |
1123 | * labelset_of_merge - find into which labelset a merged label should be inserted | |
1124 | * @a: label to merge and insert | |
1125 | * @b: label to merge and insert | |
1126 | * | |
1127 | * Returns: labelset that the merged label should be inserted into | |
1128 | */ | |
1129 | static struct aa_labelset *labelset_of_merge(struct aa_label *a, struct aa_label *b) | |
1130 | { | |
1131 | struct aa_ns *nsa = labels_ns(a); | |
1132 | struct aa_ns *nsb = labels_ns(b); | |
1133 | ||
1134 | if (ns_cmp(nsa, nsb) <= 0) | |
1135 | return &nsa->labels; | |
1136 | return &nsb->labels; | |
1137 | } | |
1138 | ||
1139 | /** | |
1140 | * __label_find_merge - find label that is equiv to merge of @a and @b | |
1141 | * @ls: set of labels to search (NOT NULL) | |
1142 | * @a: label to merge with @b (NOT NULL) | |
1143 | * @b: label to merge with @a (NOT NULL) | |
1144 | * | |
1145 | * Requires: ls->lock read_lock held | |
1146 | * | |
1147 | * Returns: ref counted label that is equiv to merge of @a and @b | |
1148 | * else NULL if merge of @a and @b is not in set | |
1149 | */ | |
1150 | static struct aa_label *__label_find_merge(struct aa_labelset *ls, | |
1151 | struct aa_label *a, | |
1152 | struct aa_label *b) | |
1153 | { | |
1154 | struct rb_node *node; | |
1155 | ||
1156 | AA_BUG(!ls); | |
1157 | AA_BUG(!a); | |
1158 | AA_BUG(!b); | |
1159 | ||
1160 | if (a == b) | |
1161 | return __label_find(a); | |
1162 | ||
1163 | node = ls->root.rb_node; | |
1164 | while (node) { | |
1165 | struct aa_label *this = container_of(node, struct aa_label, | |
1166 | node); | |
1167 | int result = label_merge_cmp(a, b, this); | |
1168 | ||
1169 | if (result < 0) | |
1170 | node = node->rb_left; | |
1171 | else if (result > 0) | |
1172 | node = node->rb_right; | |
1173 | else | |
1174 | return aa_get_label_not0(this); | |
1175 | } | |
1176 | ||
1177 | return NULL; | |
1178 | } | |
1179 | ||
1180 | ||
1181 | /** | |
1182 | * aa_label_find_merge - find label that is equiv to merge of @a and @b | |
1183 | * @a: label to merge with @b (NOT NULL) | |
1184 | * @b: label to merge with @a (NOT NULL) | |
1185 | * | |
1186 | * Requires: labels be fully constructed with a valid ns | |
1187 | * | |
1188 | * Returns: ref counted label that is equiv to merge of @a and @b | |
1189 | * else NULL if merge of @a and @b is not in set | |
1190 | */ | |
1191 | struct aa_label *aa_label_find_merge(struct aa_label *a, struct aa_label *b) | |
1192 | { | |
1193 | struct aa_labelset *ls; | |
1194 | struct aa_label *label, *ar = NULL, *br = NULL; | |
1195 | unsigned long flags; | |
1196 | ||
1197 | AA_BUG(!a); | |
1198 | AA_BUG(!b); | |
1199 | ||
1200 | if (label_is_stale(a)) | |
1201 | a = ar = aa_get_newest_label(a); | |
1202 | if (label_is_stale(b)) | |
1203 | b = br = aa_get_newest_label(b); | |
1204 | ls = labelset_of_merge(a, b); | |
1205 | read_lock_irqsave(&ls->lock, flags); | |
1206 | label = __label_find_merge(ls, a, b); | |
1207 | read_unlock_irqrestore(&ls->lock, flags); | |
1208 | aa_put_label(ar); | |
1209 | aa_put_label(br); | |
1210 | labelsetstats_inc(ls, msread); | |
1211 | ||
1212 | return label; | |
1213 | } | |
1214 | ||
1215 | /** | |
1216 | * aa_label_merge - attempt to insert new merged label of @a and @b | |
1217 | * @ls: set of labels to insert label into (NOT NULL) | |
1218 | * @a: label to merge with @b (NOT NULL) | |
1219 | * @b: label to merge with @a (NOT NULL) | |
1220 | * @gfp: memory allocation type | |
1221 | * | |
1222 | * Requires: caller to hold valid refs on @a and @b | |
1223 | * labels be fully constructed with a valid ns | |
1224 | * | |
1225 | * Returns: ref counted new label if successful in inserting merge of a & b | |
1226 | * else ref counted equivalent label that is already in the set. | |
1227 | * else NULL if could not create label (-ENOMEM) | |
1228 | */ | |
1229 | struct aa_label *aa_label_merge(struct aa_label *a, struct aa_label *b, | |
1230 | gfp_t gfp) | |
1231 | { | |
1232 | struct aa_label *label = NULL; | |
1233 | ||
1234 | AA_BUG(!a); | |
1235 | AA_BUG(!b); | |
1236 | ||
1237 | if (a == b) | |
1238 | return aa_get_newest_label(a); | |
1239 | ||
1240 | /* TODO: enable when read side is lockless | |
1241 | * check if label exists before taking locks | |
1242 | if (!label_is_stale(a) && !label_is_stale(b)) | |
1243 | label = aa_label_find_merge(a, b); | |
1244 | */ | |
1245 | ||
1246 | if (!label) { | |
1247 | struct aa_label *new; | |
1248 | ||
1249 | a = aa_get_newest_label(a); | |
1250 | b = aa_get_newest_label(b); | |
1251 | ||
1252 | /* could use label_merge_len(a, b), but requires double | |
1253 | * comparison for small savings | |
1254 | */ | |
1255 | new = aa_label_alloc(a->size + b->size, NULL, gfp); | |
1256 | if (!new) | |
1257 | goto out; | |
1258 | ||
1259 | label = label_merge_insert(new, a, b); | |
a8b02048 | 1260 | label_free_or_put_new(label, new); |
80594fc2 JJ |
1261 | out: |
1262 | aa_put_label(a); | |
1263 | aa_put_label(b); | |
1264 | } | |
1265 | ||
1266 | return label; | |
1267 | } | |
1268 | ||
1269 | static inline bool label_is_visible(struct aa_profile *profile, | |
1270 | struct aa_label *label) | |
1271 | { | |
1272 | return aa_ns_visible(profile->ns, labels_ns(label), true); | |
1273 | } | |
1274 | ||
1275 | /* match a profile and its associated ns component if needed | |
1276 | * Assumes visibility test has already been done. | |
1277 | * If a subns profile is not to be matched should be prescreened with | |
1278 | * visibility test. | |
1279 | */ | |
1280 | static inline unsigned int match_component(struct aa_profile *profile, | |
1281 | struct aa_profile *tp, | |
1282 | unsigned int state) | |
1283 | { | |
1284 | const char *ns_name; | |
1285 | ||
1286 | if (profile->ns == tp->ns) | |
1287 | return aa_dfa_match(profile->policy.dfa, state, tp->base.hname); | |
1288 | ||
1289 | /* try matching with namespace name and then profile */ | |
1290 | ns_name = aa_ns_name(profile->ns, tp->ns, true); | |
1291 | state = aa_dfa_match_len(profile->policy.dfa, state, ":", 1); | |
1292 | state = aa_dfa_match(profile->policy.dfa, state, ns_name); | |
1293 | state = aa_dfa_match_len(profile->policy.dfa, state, ":", 1); | |
1294 | return aa_dfa_match(profile->policy.dfa, state, tp->base.hname); | |
1295 | } | |
1296 | ||
1297 | /** | |
1298 | * label_component_match - find perms for full compound label | |
1299 | * @profile: profile to find perms for | |
1300 | * @label: label to check access permissions for | |
1301 | * @start: state to start match in | |
1302 | * @subns: whether to do permission checks on components in a subns | |
1303 | * @request: permissions to request | |
1304 | * @perms: perms struct to set | |
1305 | * | |
1306 | * Returns: 0 on success else ERROR | |
1307 | * | |
1308 | * For the label A//&B//&C this does the perm match for A//&B//&C | |
1309 | * @perms should be preinitialized with allperms OR a previous permission | |
1310 | * check to be stacked. | |
1311 | */ | |
1312 | static int label_compound_match(struct aa_profile *profile, | |
1313 | struct aa_label *label, | |
1314 | unsigned int state, bool subns, u32 request, | |
1315 | struct aa_perms *perms) | |
1316 | { | |
1317 | struct aa_profile *tp; | |
1318 | struct label_it i; | |
1319 | ||
1320 | /* find first subcomponent that is visible */ | |
1321 | label_for_each(i, label, tp) { | |
1322 | if (!aa_ns_visible(profile->ns, tp->ns, subns)) | |
1323 | continue; | |
1324 | state = match_component(profile, tp, state); | |
1325 | if (!state) | |
1326 | goto fail; | |
1327 | goto next; | |
1328 | } | |
1329 | ||
1330 | /* no component visible */ | |
1331 | *perms = allperms; | |
1332 | return 0; | |
1333 | ||
1334 | next: | |
1335 | label_for_each_cont(i, label, tp) { | |
1336 | if (!aa_ns_visible(profile->ns, tp->ns, subns)) | |
1337 | continue; | |
1338 | state = aa_dfa_match(profile->policy.dfa, state, "//&"); | |
1339 | state = match_component(profile, tp, state); | |
1340 | if (!state) | |
1341 | goto fail; | |
1342 | } | |
1343 | aa_compute_perms(profile->policy.dfa, state, perms); | |
1344 | aa_apply_modes_to_perms(profile, perms); | |
1345 | if ((perms->allow & request) != request) | |
1346 | return -EACCES; | |
1347 | ||
1348 | return 0; | |
1349 | ||
1350 | fail: | |
1351 | *perms = nullperms; | |
1352 | return state; | |
1353 | } | |
1354 | ||
1355 | /** | |
1356 | * label_component_match - find perms for all subcomponents of a label | |
1357 | * @profile: profile to find perms for | |
1358 | * @label: label to check access permissions for | |
1359 | * @start: state to start match in | |
1360 | * @subns: whether to do permission checks on components in a subns | |
1361 | * @request: permissions to request | |
1362 | * @perms: an initialized perms struct to add accumulation to | |
1363 | * | |
1364 | * Returns: 0 on success else ERROR | |
1365 | * | |
1366 | * For the label A//&B//&C this does the perm match for each of A and B and C | |
1367 | * @perms should be preinitialized with allperms OR a previous permission | |
1368 | * check to be stacked. | |
1369 | */ | |
1370 | static int label_components_match(struct aa_profile *profile, | |
1371 | struct aa_label *label, unsigned int start, | |
1372 | bool subns, u32 request, | |
1373 | struct aa_perms *perms) | |
1374 | { | |
1375 | struct aa_profile *tp; | |
1376 | struct label_it i; | |
1377 | struct aa_perms tmp; | |
1378 | unsigned int state = 0; | |
1379 | ||
1380 | /* find first subcomponent to test */ | |
1381 | label_for_each(i, label, tp) { | |
1382 | if (!aa_ns_visible(profile->ns, tp->ns, subns)) | |
1383 | continue; | |
1384 | state = match_component(profile, tp, start); | |
1385 | if (!state) | |
1386 | goto fail; | |
1387 | goto next; | |
1388 | } | |
1389 | ||
1390 | /* no subcomponents visible - no change in perms */ | |
1391 | return 0; | |
1392 | ||
1393 | next: | |
1394 | aa_compute_perms(profile->policy.dfa, state, &tmp); | |
1395 | aa_apply_modes_to_perms(profile, &tmp); | |
1396 | aa_perms_accum(perms, &tmp); | |
1397 | label_for_each_cont(i, label, tp) { | |
1398 | if (!aa_ns_visible(profile->ns, tp->ns, subns)) | |
1399 | continue; | |
1400 | state = match_component(profile, tp, start); | |
1401 | if (!state) | |
1402 | goto fail; | |
1403 | aa_compute_perms(profile->policy.dfa, state, &tmp); | |
1404 | aa_apply_modes_to_perms(profile, &tmp); | |
1405 | aa_perms_accum(perms, &tmp); | |
1406 | } | |
1407 | ||
1408 | if ((perms->allow & request) != request) | |
1409 | return -EACCES; | |
1410 | ||
1411 | return 0; | |
1412 | ||
1413 | fail: | |
1414 | *perms = nullperms; | |
1415 | return -EACCES; | |
1416 | } | |
1417 | ||
1418 | /** | |
1419 | * aa_label_match - do a multi-component label match | |
1420 | * @profile: profile to match against (NOT NULL) | |
1421 | * @label: label to match (NOT NULL) | |
1422 | * @state: state to start in | |
1423 | * @subns: whether to match subns components | |
1424 | * @request: permission request | |
1425 | * @perms: Returns computed perms (NOT NULL) | |
1426 | * | |
1427 | * Returns: the state the match finished in, may be the none matching state | |
1428 | */ | |
1429 | int aa_label_match(struct aa_profile *profile, struct aa_label *label, | |
1430 | unsigned int state, bool subns, u32 request, | |
1431 | struct aa_perms *perms) | |
1432 | { | |
1433 | int error = label_compound_match(profile, label, state, subns, request, | |
1434 | perms); | |
1435 | if (!error) | |
1436 | return error; | |
1437 | ||
1438 | *perms = allperms; | |
1439 | return label_components_match(profile, label, state, subns, request, | |
1440 | perms); | |
1441 | } | |
1442 | ||
1443 | ||
1444 | /** | |
1445 | * aa_update_label_name - update a label to have a stored name | |
1446 | * @ns: ns being viewed from (NOT NULL) | |
1447 | * @label: label to update (NOT NULL) | |
1448 | * @gfp: type of memory allocation | |
1449 | * | |
1450 | * Requires: labels_set(label) not locked in caller | |
1451 | * | |
1452 | * note: only updates the label name if it does not have a name already | |
1453 | * and if it is in the labelset | |
1454 | */ | |
1455 | bool aa_update_label_name(struct aa_ns *ns, struct aa_label *label, gfp_t gfp) | |
1456 | { | |
1457 | struct aa_labelset *ls; | |
1458 | unsigned long flags; | |
1459 | char __counted *name; | |
1460 | bool res = false; | |
1461 | ||
1462 | AA_BUG(!ns); | |
1463 | AA_BUG(!label); | |
1464 | ||
1465 | if (label->hname || labels_ns(label) != ns) | |
1466 | return res; | |
1467 | ||
1468 | if (aa_label_acntsxprint(&name, ns, label, FLAGS_NONE, gfp) == -1) | |
1469 | return res; | |
1470 | ||
1471 | ls = labels_set(label); | |
1472 | write_lock_irqsave(&ls->lock, flags); | |
1473 | if (!label->hname && label->flags & FLAG_IN_TREE) { | |
1474 | label->hname = name; | |
1475 | res = true; | |
1476 | } else | |
1477 | aa_put_str(name); | |
1478 | write_unlock_irqrestore(&ls->lock, flags); | |
1479 | ||
1480 | return res; | |
1481 | } | |
1482 | ||
1483 | /* cached label name is present and visible | |
1484 | * @label->hname only exists if label is namespace hierachical */ | |
1485 | static inline bool use_label_hname(struct aa_ns *ns, struct aa_label *label) | |
1486 | { | |
1487 | if (label->hname && labels_ns(label) == ns) | |
1488 | return true; | |
1489 | ||
1490 | return false; | |
1491 | } | |
1492 | ||
1493 | /* helper macro for snprint routines */ | |
1494 | #define update_for_len(total, len, size, str) \ | |
1495 | do { \ | |
1496 | AA_BUG(len < 0); \ | |
1497 | total += len; \ | |
1498 | len = min(len, size); \ | |
1499 | size -= len; \ | |
1500 | str += len; \ | |
1501 | } while (0) | |
1502 | ||
1503 | /** | |
1504 | * aa_profile_snxprint_profile - print a profile name to a buffer | |
1505 | * @str: buffer to write to. (MAY BE NULL if @size == 0) | |
1506 | * @size: size of buffer | |
1507 | * @ns: namespace profile is being viewed from | |
1508 | * @profile: profile to view (NOT NULL) | |
1509 | * @flags: whether to include the mode string | |
1510 | * | |
1511 | * Returns: size of name written or would be written if larger than | |
1512 | * available buffer | |
1513 | * | |
1514 | * Note: will not print anything if the profile is not visible | |
1515 | */ | |
1516 | int aa_profile_snxprint(char *str, size_t size, struct aa_ns *ns, | |
1517 | struct aa_profile *profile, int flags) | |
1518 | { | |
1519 | const char *ns_name = ""; | |
1520 | ||
1521 | AA_BUG(!str && size != 0); | |
1522 | AA_BUG(!profile); | |
1523 | ||
1524 | if (!ns) | |
1525 | ns = profiles_ns(profile); | |
1526 | ||
1527 | if (ns != profile->ns) { | |
1528 | ns_name = aa_ns_name(ns, profile->ns, flags & FLAG_VIEW_SUBNS); | |
1529 | if (ns_name == aa_hidden_ns_name) { | |
1530 | if (flags & FLAG_HIDDEN_UNCONFINED) | |
1531 | return snprintf(str, size, "%s", "unconfined"); | |
1532 | return snprintf(str, size, "%s", ns_name); | |
1533 | } | |
1534 | } | |
1535 | ||
1536 | if ((flags & FLAG_SHOW_MODE) && profile != profile->ns->unconfined) { | |
1537 | const char *modestr = aa_profile_mode_names[profile->mode]; | |
1538 | if (strlen(ns_name)) | |
1539 | return snprintf(str, size, ":%s://%s (%s)", ns_name, | |
1540 | profile->base.hname, modestr); | |
1541 | return snprintf(str, size, "%s (%s)", profile->base.hname, | |
1542 | modestr); | |
1543 | } | |
1544 | ||
1545 | if (strlen(ns_name)) | |
1546 | return snprintf(str, size, ":%s://%s", ns_name, | |
1547 | profile->base.hname); | |
1548 | return snprintf(str, size, "%s", profile->base.hname); | |
1549 | } | |
1550 | ||
1551 | static const char *label_modename(struct aa_ns *ns, struct aa_label *label, | |
1552 | int flags) | |
1553 | { | |
1554 | struct aa_profile *profile; | |
1555 | struct label_it i; | |
5c068217 | 1556 | int mode = -1, count = 0; |
80594fc2 JJ |
1557 | |
1558 | label_for_each(i, label, profile) { | |
1559 | if (aa_ns_visible(ns, profile->ns, flags & FLAG_VIEW_SUBNS)) { | |
5c068217 JJ |
1560 | if (profile->mode == APPARMOR_UNCONFINED) |
1561 | /* special case unconfined so stacks with | |
1562 | * unconfined don't report as mixed. ie. | |
1563 | * profile_foo//&:ns1://unconfined (mixed) | |
1564 | */ | |
1565 | continue; | |
80594fc2 | 1566 | count++; |
5c068217 JJ |
1567 | if (mode == -1) |
1568 | mode = profile->mode; | |
1569 | else if (mode != profile->mode) | |
80594fc2 JJ |
1570 | return "mixed"; |
1571 | } | |
1572 | } | |
1573 | ||
1574 | if (count == 0) | |
1575 | return "-"; | |
5c068217 JJ |
1576 | if (mode == -1) |
1577 | /* everything was unconfined */ | |
1578 | mode = APPARMOR_UNCONFINED; | |
80594fc2 | 1579 | |
5c068217 | 1580 | return aa_profile_mode_names[mode]; |
80594fc2 JJ |
1581 | } |
1582 | ||
1583 | /* if any visible label is not unconfined the display_mode returns true */ | |
1584 | static inline bool display_mode(struct aa_ns *ns, struct aa_label *label, | |
1585 | int flags) | |
1586 | { | |
1587 | if ((flags & FLAG_SHOW_MODE)) { | |
1588 | struct aa_profile *profile; | |
1589 | struct label_it i; | |
1590 | ||
1591 | label_for_each(i, label, profile) { | |
1592 | if (aa_ns_visible(ns, profile->ns, | |
1593 | flags & FLAG_VIEW_SUBNS) && | |
1594 | profile != profile->ns->unconfined) | |
1595 | return true; | |
1596 | } | |
1597 | /* only ns->unconfined in set of profiles in ns */ | |
1598 | return false; | |
1599 | } | |
1600 | ||
1601 | return false; | |
1602 | } | |
1603 | ||
1604 | /** | |
1605 | * aa_label_snxprint - print a label name to a string buffer | |
1606 | * @str: buffer to write to. (MAY BE NULL if @size == 0) | |
1607 | * @size: size of buffer | |
1608 | * @ns: namespace profile is being viewed from | |
1609 | * @label: label to view (NOT NULL) | |
1610 | * @flags: whether to include the mode string | |
1611 | * | |
1612 | * Returns: size of name written or would be written if larger than | |
1613 | * available buffer | |
1614 | * | |
1615 | * Note: labels do not have to be strictly hierarchical to the ns as | |
1616 | * objects may be shared across different namespaces and thus | |
1617 | * pickup labeling from each ns. If a particular part of the | |
1618 | * label is not visible it will just be excluded. And if none | |
1619 | * of the label is visible "---" will be used. | |
1620 | */ | |
1621 | int aa_label_snxprint(char *str, size_t size, struct aa_ns *ns, | |
1622 | struct aa_label *label, int flags) | |
1623 | { | |
1624 | struct aa_profile *profile; | |
1625 | struct label_it i; | |
1626 | int count = 0, total = 0; | |
1627 | size_t len; | |
1628 | ||
1629 | AA_BUG(!str && size != 0); | |
1630 | AA_BUG(!label); | |
1631 | ||
1632 | if (!ns) | |
1633 | ns = labels_ns(label); | |
1634 | ||
1635 | label_for_each(i, label, profile) { | |
1636 | if (aa_ns_visible(ns, profile->ns, flags & FLAG_VIEW_SUBNS)) { | |
1637 | if (count > 0) { | |
1638 | len = snprintf(str, size, "//&"); | |
1639 | update_for_len(total, len, size, str); | |
1640 | } | |
1641 | len = aa_profile_snxprint(str, size, ns, profile, | |
1642 | flags & FLAG_VIEW_SUBNS); | |
1643 | update_for_len(total, len, size, str); | |
1644 | count++; | |
1645 | } | |
1646 | } | |
1647 | ||
1648 | if (count == 0) { | |
1649 | if (flags & FLAG_HIDDEN_UNCONFINED) | |
1650 | return snprintf(str, size, "%s", "unconfined"); | |
1651 | return snprintf(str, size, "%s", aa_hidden_ns_name); | |
1652 | } | |
1653 | ||
1654 | /* count == 1 && ... is for backwards compat where the mode | |
1655 | * is not displayed for 'unconfined' in the current ns | |
1656 | */ | |
1657 | if (display_mode(ns, label, flags)) { | |
1658 | len = snprintf(str, size, " (%s)", | |
1659 | label_modename(ns, label, flags)); | |
1660 | update_for_len(total, len, size, str); | |
1661 | } | |
1662 | ||
1663 | return total; | |
1664 | } | |
1665 | #undef update_for_len | |
1666 | ||
1667 | /** | |
1668 | * aa_label_asxprint - allocate a string buffer and print label into it | |
1669 | * @strp: Returns - the allocated buffer with the label name. (NOT NULL) | |
1670 | * @ns: namespace profile is being viewed from | |
1671 | * @label: label to view (NOT NULL) | |
1672 | * @flags: flags controlling what label info is printed | |
1673 | * @gfp: kernel memory allocation type | |
1674 | * | |
1675 | * Returns: size of name written or would be written if larger than | |
1676 | * available buffer | |
1677 | */ | |
1678 | int aa_label_asxprint(char **strp, struct aa_ns *ns, struct aa_label *label, | |
1679 | int flags, gfp_t gfp) | |
1680 | { | |
1681 | int size; | |
1682 | ||
1683 | AA_BUG(!strp); | |
1684 | AA_BUG(!label); | |
1685 | ||
1686 | size = aa_label_snxprint(NULL, 0, ns, label, flags); | |
1687 | if (size < 0) | |
1688 | return size; | |
1689 | ||
1690 | *strp = kmalloc(size + 1, gfp); | |
1691 | if (!*strp) | |
1692 | return -ENOMEM; | |
1693 | return aa_label_snxprint(*strp, size + 1, ns, label, flags); | |
1694 | } | |
1695 | ||
1696 | /** | |
1697 | * aa_label_acntsxprint - allocate a __counted string buffer and print label | |
1698 | * @strp: buffer to write to. (MAY BE NULL if @size == 0) | |
1699 | * @ns: namespace profile is being viewed from | |
1700 | * @label: label to view (NOT NULL) | |
1701 | * @flags: flags controlling what label info is printed | |
1702 | * @gfp: kernel memory allocation type | |
1703 | * | |
1704 | * Returns: size of name written or would be written if larger than | |
1705 | * available buffer | |
1706 | */ | |
1707 | int aa_label_acntsxprint(char __counted **strp, struct aa_ns *ns, | |
1708 | struct aa_label *label, int flags, gfp_t gfp) | |
1709 | { | |
1710 | int size; | |
1711 | ||
1712 | AA_BUG(!strp); | |
1713 | AA_BUG(!label); | |
1714 | ||
1715 | size = aa_label_snxprint(NULL, 0, ns, label, flags); | |
1716 | if (size < 0) | |
1717 | return size; | |
1718 | ||
1719 | *strp = aa_str_alloc(size + 1, gfp); | |
1720 | if (!*strp) | |
1721 | return -ENOMEM; | |
1722 | return aa_label_snxprint(*strp, size + 1, ns, label, flags); | |
1723 | } | |
1724 | ||
1725 | ||
1726 | void aa_label_xaudit(struct audit_buffer *ab, struct aa_ns *ns, | |
1727 | struct aa_label *label, int flags, gfp_t gfp) | |
1728 | { | |
1729 | const char *str; | |
1730 | char *name = NULL; | |
1731 | int len; | |
1732 | ||
1733 | AA_BUG(!ab); | |
1734 | AA_BUG(!label); | |
1735 | ||
1736 | if (!ns) | |
1737 | ns = labels_ns(label); | |
1738 | ||
1739 | if (!use_label_hname(ns, label) || display_mode(ns, label, flags)) { | |
1740 | labelstats_inc(audit_name_alloc); | |
1741 | len = aa_label_asxprint(&name, ns, label, flags, gfp); | |
1742 | if (len == -1) { | |
1743 | labelstats_inc(audit_name_fail); | |
1744 | AA_DEBUG("label print error"); | |
1745 | return; | |
1746 | } | |
1747 | str = name; | |
1748 | } else { | |
1749 | str = (char *) label->hname; | |
1750 | len = strlen(str); | |
1751 | } | |
1752 | if (audit_string_contains_control(str, len)) | |
1753 | audit_log_n_hex(ab, str, len); | |
1754 | else | |
1755 | audit_log_n_string(ab, str, len); | |
1756 | ||
1757 | kfree(name); | |
1758 | } | |
1759 | ||
1760 | void aa_label_seq_xprint(struct seq_file *f, struct aa_ns *ns, | |
1761 | struct aa_label *label, int flags, gfp_t gfp) | |
1762 | { | |
1763 | AA_BUG(!f); | |
1764 | AA_BUG(!label); | |
1765 | ||
1766 | if (!ns) | |
1767 | ns = labels_ns(label); | |
1768 | ||
1769 | if (!use_label_hname(ns, label)) { | |
1770 | char *str; | |
1771 | int len; | |
1772 | ||
1773 | labelstats_inc(seq_print_name_alloc); | |
1774 | len = aa_label_asxprint(&str, ns, label, flags, gfp); | |
1775 | if (len == -1) { | |
1776 | labelstats_inc(seq_print_name_fail); | |
1777 | AA_DEBUG("label print error"); | |
1778 | return; | |
1779 | } | |
1780 | seq_printf(f, "%s", str); | |
1781 | kfree(str); | |
1782 | } else if (display_mode(ns, label, flags)) | |
1783 | seq_printf(f, "%s (%s)", label->hname, | |
1784 | label_modename(ns, label, flags)); | |
1785 | else | |
1786 | seq_printf(f, "%s", label->hname); | |
1787 | } | |
1788 | ||
1789 | void aa_label_xprintk(struct aa_ns *ns, struct aa_label *label, int flags, | |
1790 | gfp_t gfp) | |
1791 | { | |
1792 | AA_BUG(!label); | |
1793 | ||
1794 | if (!ns) | |
1795 | ns = labels_ns(label); | |
1796 | ||
1797 | if (!use_label_hname(ns, label)) { | |
1798 | char *str; | |
1799 | int len; | |
1800 | ||
1801 | labelstats_inc(printk_name_alloc); | |
1802 | len = aa_label_asxprint(&str, ns, label, flags, gfp); | |
1803 | if (len == -1) { | |
1804 | labelstats_inc(printk_name_fail); | |
1805 | AA_DEBUG("label print error"); | |
1806 | return; | |
1807 | } | |
1808 | printk("%s", str); | |
1809 | kfree(str); | |
1810 | } else if (display_mode(ns, label, flags)) | |
1811 | printk("%s (%s)", label->hname, | |
1812 | label_modename(ns, label, flags)); | |
1813 | else | |
1814 | printk("%s", label->hname); | |
1815 | } | |
1816 | ||
1817 | void aa_label_audit(struct audit_buffer *ab, struct aa_label *label, gfp_t gfp) | |
1818 | { | |
1819 | struct aa_ns *ns = aa_get_current_ns(); | |
1820 | aa_label_xaudit(ab, ns, label, FLAG_VIEW_SUBNS, gfp); | |
1821 | aa_put_ns(ns); | |
1822 | } | |
1823 | ||
1824 | void aa_label_seq_print(struct seq_file *f, struct aa_label *label, gfp_t gfp) | |
1825 | { | |
1826 | struct aa_ns *ns = aa_get_current_ns(); | |
1827 | aa_label_seq_xprint(f, ns, label, FLAG_VIEW_SUBNS, gfp); | |
1828 | aa_put_ns(ns); | |
1829 | } | |
1830 | ||
1831 | void aa_label_printk(struct aa_label *label, gfp_t gfp) | |
1832 | { | |
1833 | struct aa_ns *ns = aa_get_current_ns(); | |
1834 | aa_label_xprintk(ns, label, FLAG_VIEW_SUBNS, gfp); | |
1835 | aa_put_ns(ns); | |
1836 | } | |
1837 | ||
1838 | static int label_count_str_entries(const char *str) | |
1839 | { | |
1840 | const char *split; | |
1841 | int count = 1; | |
1842 | ||
1843 | AA_BUG(!str); | |
1844 | ||
1845 | for (split = strstr(str, "//&"); split; split = strstr(str, "//&")) { | |
1846 | count++; | |
1847 | str = split + 3; | |
1848 | } | |
1849 | ||
1850 | return count; | |
1851 | } | |
1852 | ||
bd5bc987 JJ |
1853 | /* |
1854 | * ensure stacks with components like | |
1855 | * :ns://A//&B | |
1856 | * have :ns: applied to both 'A' and 'B' by making the lookup relative | |
1857 | * to the base if the lookup specifies an ns, else making the stacked lookup | |
1858 | * relative to the last embedded ns in the string. | |
1859 | */ | |
1860 | static struct aa_profile *fqlookupn_profile(struct aa_label *base, | |
1861 | struct aa_label *currentbase, | |
1862 | const char *str, size_t n) | |
1863 | { | |
1864 | const char *first = skipn_spaces(str, n); | |
1865 | if (first && *first == ':') | |
1866 | return aa_fqlookupn_profile(base, str, n); | |
1867 | return aa_fqlookupn_profile(currentbase, str, n); | |
1868 | } | |
1869 | ||
80594fc2 JJ |
1870 | /** |
1871 | * aa_label_parse - parse, validate and convert a text string to a label | |
1872 | * @base: base label to use for lookups (NOT NULL) | |
1873 | * @str: null terminated text string (NOT NULL) | |
1874 | * @gfp: allocation type | |
1875 | * @create: true if should create compound labels if they don't exist | |
1876 | * @force_stack: true if should stack even if no leading & | |
1877 | * | |
1878 | * Returns: the matching refcounted label if present | |
1879 | * else ERRPTR | |
1880 | */ | |
1881 | struct aa_label *aa_label_parse(struct aa_label *base, const char *str, | |
1882 | gfp_t gfp, bool create, bool force_stack) | |
1883 | { | |
1884 | DEFINE_VEC(profile, vec); | |
bd5bc987 | 1885 | struct aa_label *label, *currbase = base; |
80594fc2 JJ |
1886 | int i, len, stack = 0, error; |
1887 | char *split; | |
1888 | ||
1889 | AA_BUG(!base); | |
1890 | AA_BUG(!str); | |
1891 | ||
1892 | str = skip_spaces(str); | |
1893 | len = label_count_str_entries(str); | |
1894 | if (*str == '&' || force_stack) { | |
1895 | /* stack on top of base */ | |
1896 | stack = base->size; | |
1897 | len += stack; | |
1898 | if (*str == '&') | |
1899 | str++; | |
1900 | } | |
1901 | error = vec_setup(profile, vec, len, gfp); | |
1902 | if (error) | |
1903 | return ERR_PTR(error); | |
1904 | ||
1905 | for (i = 0; i < stack; i++) | |
1906 | vec[i] = aa_get_profile(base->vec[i]); | |
1907 | ||
1908 | for (split = strstr(str, "//&"), i = stack; split && i < len; i++) { | |
bd5bc987 | 1909 | vec[i] = fqlookupn_profile(base, currbase, str, split - str); |
80594fc2 JJ |
1910 | if (!vec[i]) |
1911 | goto fail; | |
bd5bc987 JJ |
1912 | /* |
1913 | * if component specified a new ns it becomes the new base | |
1914 | * so that subsequent lookups are relative to it | |
1915 | */ | |
1916 | if (vec[i]->ns != labels_ns(currbase)) | |
1917 | currbase = &vec[i]->label; | |
80594fc2 JJ |
1918 | str = split + 3; |
1919 | split = strstr(str, "//&"); | |
1920 | } | |
1921 | /* last element doesn't have a split so this should be the case but just to be safe */ | |
1922 | if (i < len) { | |
bd5bc987 | 1923 | vec[i] = fqlookupn_profile(base, currbase, str, strlen(str)); |
80594fc2 JJ |
1924 | if (!vec[i]) |
1925 | goto fail; | |
1926 | } | |
1927 | if (len == 1) | |
1928 | /* no need to free vec as len < LOCAL_VEC_ENTRIES */ | |
1929 | return &vec[0]->label; | |
1930 | ||
1931 | len -= aa_vec_unique(vec, len, VEC_FLAG_TERMINATE); | |
6c96ac34 JJ |
1932 | /* TODO: deal with reference labels */ |
1933 | if (len == 1) { | |
1934 | label = aa_get_label(&vec[0]->label); | |
1935 | goto out; | |
1936 | } | |
80594fc2 JJ |
1937 | |
1938 | if (create) | |
1939 | label = aa_vec_find_or_create_label(vec, len, gfp); | |
1940 | else | |
1941 | label = vec_find(vec, len); | |
1942 | if (!label) | |
1943 | goto fail; | |
1944 | ||
1945 | out: | |
1946 | /* use adjusted len from after vec_unique, not original */ | |
1947 | vec_cleanup(profile, vec, len); | |
1948 | return label; | |
1949 | ||
1950 | fail: | |
1951 | label = ERR_PTR(-ENOENT); | |
1952 | goto out; | |
1953 | } | |
1954 | ||
1955 | ||
1956 | /** | |
1957 | * aa_labelset_destroy - remove all labels from the label set | |
1958 | * @ls: label set to cleanup (NOT NULL) | |
1959 | * | |
1960 | * Labels that are removed from the set may still exist beyond the set | |
1961 | * being destroyed depending on their reference counting | |
1962 | */ | |
1963 | void aa_labelset_destroy(struct aa_labelset *ls) | |
1964 | { | |
1965 | struct rb_node *node; | |
1966 | unsigned long flags; | |
1967 | ||
1968 | AA_BUG(!ls); | |
1969 | ||
1970 | write_lock_irqsave(&ls->lock, flags); | |
1971 | for (node = rb_first(&ls->root); node; node = rb_first(&ls->root)) { | |
1972 | struct aa_label *this = rb_entry(node, struct aa_label, node); | |
1973 | if (labels_ns(this) != root_ns) | |
1974 | __label_remove(this, | |
1975 | ns_unconfined(labels_ns(this)->parent)); | |
1976 | else | |
1977 | __label_remove(this, NULL); | |
1978 | } | |
1979 | write_unlock_irqrestore(&ls->lock, flags); | |
1980 | } | |
1981 | ||
1982 | /* | |
1983 | * @ls: labelset to init (NOT NULL) | |
1984 | */ | |
1985 | void aa_labelset_init(struct aa_labelset *ls) | |
1986 | { | |
1987 | AA_BUG(!ls); | |
1988 | ||
1989 | rwlock_init(&ls->lock); | |
1990 | ls->root = RB_ROOT; | |
1991 | labelstats_init(&ls); | |
1992 | } | |
1993 | ||
1994 | static struct aa_label *labelset_next_stale(struct aa_labelset *ls) | |
1995 | { | |
1996 | struct aa_label *label; | |
1997 | struct rb_node *node; | |
1998 | unsigned long flags; | |
1999 | ||
2000 | AA_BUG(!ls); | |
2001 | ||
2002 | read_lock_irqsave(&ls->lock, flags); | |
2003 | ||
2004 | __labelset_for_each(ls, node) { | |
2005 | label = rb_entry(node, struct aa_label, node); | |
2006 | if ((label_is_stale(label) || vec_is_stale(label->vec, label->size)) && | |
2007 | aa_get_label_not0(label)) | |
2008 | goto out; | |
2009 | ||
2010 | } | |
2011 | label = NULL; | |
2012 | ||
2013 | out: | |
2014 | read_unlock_irqrestore(&ls->lock, flags); | |
2015 | ||
2016 | return label; | |
2017 | } | |
2018 | ||
2019 | /** | |
2020 | * __label_update - insert updated version of @label into labelset | |
2021 | * @label - the label to update/repace | |
2022 | * | |
2023 | * Returns: new label that is up to date | |
2024 | * else NULL on failure | |
2025 | * | |
2026 | * Requires: @ns lock be held | |
2027 | * | |
2028 | * Note: worst case is the stale @label does not get updated and has | |
2029 | * to be updated at a later time. | |
2030 | */ | |
2031 | static struct aa_label *__label_update(struct aa_label *label) | |
2032 | { | |
2033 | struct aa_label *new, *tmp; | |
2034 | struct aa_labelset *ls; | |
80594fc2 | 2035 | unsigned long flags; |
4529e31d | 2036 | int i, invcount = 0; |
80594fc2 JJ |
2037 | |
2038 | AA_BUG(!label); | |
2039 | AA_BUG(!mutex_is_locked(&labels_ns(label)->lock)); | |
2040 | ||
2041 | new = aa_label_alloc(label->size, label->proxy, GFP_KERNEL); | |
2042 | if (!new) | |
2043 | return NULL; | |
2044 | ||
2045 | /* while holding the ns_lock will stop profile replacement, removal, | |
2046 | * and label updates, label merging and removal can be occuring | |
2047 | */ | |
2048 | ls = labels_set(label); | |
2049 | write_lock_irqsave(&ls->lock, flags); | |
4529e31d | 2050 | for (i = 0; i < label->size; i++) { |
bfa31064 | 2051 | AA_BUG(!label->vec[i]); |
4529e31d | 2052 | new->vec[i] = aa_get_newest_profile(label->vec[i]); |
bfa31064 JJ |
2053 | AA_BUG(!new->vec[i]); |
2054 | AA_BUG(!new->vec[i]->label.proxy); | |
2055 | AA_BUG(!new->vec[i]->label.proxy->label); | |
4529e31d | 2056 | if (new->vec[i]->label.proxy != label->vec[i]->label.proxy) |
80594fc2 JJ |
2057 | invcount++; |
2058 | } | |
2059 | ||
2060 | /* updated stale label by being removed/renamed from labelset */ | |
2061 | if (invcount) { | |
2062 | new->size -= aa_vec_unique(&new->vec[0], new->size, | |
2063 | VEC_FLAG_TERMINATE); | |
6c96ac34 JJ |
2064 | /* TODO: deal with reference labels */ |
2065 | if (new->size == 1) { | |
2066 | tmp = aa_get_label(&new->vec[0]->label); | |
2067 | AA_BUG(tmp == label); | |
2068 | goto remove; | |
2069 | } | |
80594fc2 JJ |
2070 | if (labels_set(label) != labels_set(new)) { |
2071 | write_unlock_irqrestore(&ls->lock, flags); | |
2072 | tmp = aa_label_insert(labels_set(new), new); | |
2073 | write_lock_irqsave(&ls->lock, flags); | |
2074 | goto remove; | |
2075 | } | |
2076 | } else | |
2077 | AA_BUG(labels_ns(label) != labels_ns(new)); | |
2078 | ||
2079 | tmp = __label_insert(labels_set(label), new, true); | |
2080 | remove: | |
2081 | /* ensure label is removed, and redirected correctly */ | |
2082 | __label_remove(label, tmp); | |
2083 | write_unlock_irqrestore(&ls->lock, flags); | |
a8b02048 | 2084 | label_free_or_put_new(tmp, new); |
80594fc2 JJ |
2085 | |
2086 | return tmp; | |
2087 | } | |
2088 | ||
2089 | /** | |
2090 | * __labelset_update - update labels in @ns | |
2091 | * @ns: namespace to update labels in (NOT NULL) | |
2092 | * | |
2093 | * Requires: @ns lock be held | |
2094 | * | |
2095 | * Walk the labelset ensuring that all labels are up to date and valid | |
2096 | * Any label that has a stale component is marked stale and replaced and | |
2097 | * by an updated version. | |
2098 | * | |
2099 | * If failures happen due to memory pressures then stale labels will | |
2100 | * be left in place until the next pass. | |
2101 | */ | |
2102 | static void __labelset_update(struct aa_ns *ns) | |
2103 | { | |
2104 | struct aa_label *label; | |
2105 | ||
2106 | AA_BUG(!ns); | |
2107 | AA_BUG(!mutex_is_locked(&ns->lock)); | |
2108 | ||
2109 | do { | |
2110 | label = labelset_next_stale(&ns->labels); | |
2111 | if (label) { | |
2112 | struct aa_label *l; | |
2113 | l = __label_update(label); | |
2114 | aa_put_label(l); | |
2115 | aa_put_label(label); | |
2116 | } | |
2117 | } while (label); | |
2118 | } | |
2119 | ||
2120 | /** | |
2121 | * __aa_labelset_udate_subtree - update all labels with a stale component | |
2122 | * @ns: ns to start update at (NOT NULL) | |
2123 | * | |
2124 | * Requires: @ns lock be held | |
2125 | * | |
2126 | * Invalidates labels based on @p in @ns and any children namespaces. | |
2127 | */ | |
2128 | void __aa_labelset_update_subtree(struct aa_ns *ns) | |
2129 | { | |
2130 | struct aa_ns *child; | |
2131 | ||
2132 | AA_BUG(!ns); | |
2133 | AA_BUG(!mutex_is_locked(&ns->lock)); | |
2134 | ||
2135 | __labelset_update(ns); | |
2136 | ||
2137 | list_for_each_entry(child, &ns->sub_ns, base.list) { | |
2138 | mutex_lock(&child->lock); | |
2139 | __aa_labelset_update_subtree(child); | |
2140 | mutex_unlock(&child->lock); | |
2141 | } | |
2142 | } |