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1/*
2 * AppArmor security module
3 *
4 * This file contains AppArmor policy manipulation functions
5 *
6 * Copyright (C) 1998-2008 Novell/SUSE
7 * Copyright 2009-2010 Canonical Ltd.
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License as
11 * published by the Free Software Foundation, version 2 of the
12 * License.
13 *
14 *
15 * AppArmor policy is based around profiles, which contain the rules a
16 * task is confined by. Every task in the system has a profile attached
17 * to it determined either by matching "unconfined" tasks against the
18 * visible set of profiles or by following a profiles attachment rules.
19 *
20 * Each profile exists in a profile namespace which is a container of
21 * visible profiles. Each namespace contains a special "unconfined" profile,
22 * which doesn't enforce any confinement on a task beyond DAC.
23 *
24 * Namespace and profile names can be written together in either
25 * of two syntaxes.
26 * :namespace:profile - used by kernel interfaces for easy detection
27 * namespace://profile - used by policy
28 *
29 * Profile names can not start with : or @ or ^ and may not contain \0
30 *
31 * Reserved profile names
32 * unconfined - special automatically generated unconfined profile
33 * inherit - special name to indicate profile inheritance
34 * null-XXXX-YYYY - special automatically generated learning profiles
35 *
36 * Namespace names may not start with / or @ and may not contain \0 or :
37 * Reserved namespace names
38 * user-XXXX - user defined profiles
39 *
40 * a // in a profile or namespace name indicates a hierarchical name with the
41 * name before the // being the parent and the name after the child.
42 *
43 * Profile and namespace hierarchies serve two different but similar purposes.
44 * The namespace contains the set of visible profiles that are considered
45 * for attachment. The hierarchy of namespaces allows for virtualizing
46 * the namespace so that for example a chroot can have its own set of profiles
47 * which may define some local user namespaces.
48 * The profile hierarchy severs two distinct purposes,
49 * - it allows for sub profiles or hats, which allows an application to run
50 * subprograms under its own profile with different restriction than it
51 * self, and not have it use the system profile.
52 * eg. if a mail program starts an editor, the policy might make the
53 * restrictions tighter on the editor tighter than the mail program,
54 * and definitely different than general editor restrictions
55 * - it allows for binary hierarchy of profiles, so that execution history
56 * is preserved. This feature isn't exploited by AppArmor reference policy
57 * but is allowed. NOTE: this is currently suboptimal because profile
58 * aliasing is not currently implemented so that a profile for each
59 * level must be defined.
60 * eg. /bin/bash///bin/ls as a name would indicate /bin/ls was started
61 * from /bin/bash
62 *
63 * A profile or namespace name that can contain one or more // separators
64 * is referred to as an hname (hierarchical).
65 * eg. /bin/bash//bin/ls
66 *
67 * An fqname is a name that may contain both namespace and profile hnames.
68 * eg. :ns:/bin/bash//bin/ls
69 *
70 * NOTES:
71 * - locking of profile lists is currently fairly coarse. All profile
72 * lists within a namespace use the namespace lock.
73 * FIXME: move profile lists to using rcu_lists
74 */
75
76#include <linux/slab.h>
77#include <linux/spinlock.h>
78#include <linux/string.h>
79#include <linux/cred.h>
80#include <linux/rculist.h>
81#include <linux/user_namespace.h>
82
83#include "include/apparmor.h"
84#include "include/capability.h"
85#include "include/cred.h"
86#include "include/file.h"
87#include "include/ipc.h"
88#include "include/match.h"
89#include "include/path.h"
90#include "include/policy.h"
91#include "include/policy_ns.h"
92#include "include/policy_unpack.h"
93#include "include/resource.h"
94
95int unprivileged_userns_apparmor_policy = 1;
96
97const char *const aa_profile_mode_names[] = {
98 "enforce",
99 "complain",
100 "kill",
101 "unconfined",
102};
103
104
105/**
106 * __add_profile - add a profiles to list and label tree
107 * @list: list to add it to (NOT NULL)
108 * @profile: the profile to add (NOT NULL)
109 *
110 * refcount @profile, should be put by __list_remove_profile
111 *
112 * Requires: namespace lock be held, or list not be shared
113 */
114static void __add_profile(struct list_head *list, struct aa_profile *profile)
115{
116 struct aa_label *l;
117
118 AA_BUG(!list);
119 AA_BUG(!profile);
120 AA_BUG(!profile->ns);
121 AA_BUG(!mutex_is_locked(&profile->ns->lock));
122
123 list_add_rcu(&profile->base.list, list);
124 /* get list reference */
125 aa_get_profile(profile);
126 l = aa_label_insert(&profile->ns->labels, &profile->label);
127 AA_BUG(l != &profile->label);
128 aa_put_label(l);
129}
130
131/**
132 * __list_remove_profile - remove a profile from the list it is on
133 * @profile: the profile to remove (NOT NULL)
134 *
135 * remove a profile from the list, warning generally removal should
136 * be done with __replace_profile as most profile removals are
137 * replacements to the unconfined profile.
138 *
139 * put @profile list refcount
140 *
141 * Requires: namespace lock be held, or list not have been live
142 */
143static void __list_remove_profile(struct aa_profile *profile)
144{
145 AA_BUG(!profile);
146 AA_BUG(!profile->ns);
147 AA_BUG(!mutex_is_locked(&profile->ns->lock));
148
149 list_del_rcu(&profile->base.list);
150 aa_put_profile(profile);
151}
152
153/**
154 * __remove_profile - remove old profile, and children
155 * @profile: profile to be replaced (NOT NULL)
156 *
157 * Requires: namespace list lock be held, or list not be shared
158 */
159static void __remove_profile(struct aa_profile *profile)
160{
161 AA_BUG(!profile);
162 AA_BUG(!profile->ns);
163 AA_BUG(!mutex_is_locked(&profile->ns->lock));
164
165 /* release any children lists first */
166 __aa_profile_list_release(&profile->base.profiles);
167 /* released by free_profile */
168 aa_label_remove(&profile->label);
169 __aafs_profile_rmdir(profile);
170 __list_remove_profile(profile);
171}
172
173/**
174 * __aa_profile_list_release - remove all profiles on the list and put refs
175 * @head: list of profiles (NOT NULL)
176 *
177 * Requires: namespace lock be held
178 */
179void __aa_profile_list_release(struct list_head *head)
180{
181 struct aa_profile *profile, *tmp;
182 list_for_each_entry_safe(profile, tmp, head, base.list)
183 __remove_profile(profile);
184}
185
186/**
187 * aa_free_data - free a data blob
188 * @ptr: data to free
189 * @arg: unused
190 */
191static void aa_free_data(void *ptr, void *arg)
192{
193 struct aa_data *data = ptr;
194
195 kzfree(data->data);
196 kzfree(data->key);
197 kzfree(data);
198}
199
200/**
201 * aa_free_profile - free a profile
202 * @profile: the profile to free (MAYBE NULL)
203 *
204 * Free a profile, its hats and null_profile. All references to the profile,
205 * its hats and null_profile must have been put.
206 *
207 * If the profile was referenced from a task context, free_profile() will
208 * be called from an rcu callback routine, so we must not sleep here.
209 */
210void aa_free_profile(struct aa_profile *profile)
211{
212 struct rhashtable *rht;
213 int i;
214
215 AA_DEBUG("%s(%p)\n", __func__, profile);
216
217 if (!profile)
218 return;
219
220 /* free children profiles */
221 aa_policy_destroy(&profile->base);
222 aa_put_profile(rcu_access_pointer(profile->parent));
223
224 aa_put_ns(profile->ns);
225 kzfree(profile->rename);
226
227 aa_free_file_rules(&profile->file);
228 aa_free_cap_rules(&profile->caps);
229 aa_free_rlimit_rules(&profile->rlimits);
230
231 for (i = 0; i < profile->xattr_count; i++)
232 kzfree(profile->xattrs[i]);
233 kzfree(profile->xattrs);
234 kzfree(profile->dirname);
235 aa_put_dfa(profile->xmatch);
236 aa_put_dfa(profile->policy.dfa);
237
238 if (profile->data) {
239 rht = profile->data;
240 profile->data = NULL;
241 rhashtable_free_and_destroy(rht, aa_free_data, NULL);
242 kzfree(rht);
243 }
244
245 kzfree(profile->hash);
246 aa_put_loaddata(profile->rawdata);
247
248 kzfree(profile);
249}
250
251/**
252 * aa_alloc_profile - allocate, initialize and return a new profile
253 * @hname: name of the profile (NOT NULL)
254 * @gfp: allocation type
255 *
256 * Returns: refcount profile or NULL on failure
257 */
258struct aa_profile *aa_alloc_profile(const char *hname, struct aa_proxy *proxy,
259 gfp_t gfp)
260{
261 struct aa_profile *profile;
262
263 /* freed by free_profile - usually through aa_put_profile */
264 profile = kzalloc(sizeof(*profile) + sizeof(struct aa_profile *) * 2,
265 gfp);
266 if (!profile)
267 return NULL;
268
269 if (!aa_policy_init(&profile->base, NULL, hname, gfp))
270 goto fail;
271 if (!aa_label_init(&profile->label, 1))
272 goto fail;
273
274 /* update being set needed by fs interface */
275 if (!proxy) {
276 proxy = aa_alloc_proxy(&profile->label, gfp);
277 if (!proxy)
278 goto fail;
279 } else
280 aa_get_proxy(proxy);
281 profile->label.proxy = proxy;
282
283 profile->label.hname = profile->base.hname;
284 profile->label.flags |= FLAG_PROFILE;
285 profile->label.vec[0] = profile;
286
287 /* refcount released by caller */
288 return profile;
289
290fail:
291 aa_free_profile(profile);
292
293 return NULL;
294}
295
296/* TODO: profile accounting - setup in remove */
297
298/**
299 * __strn_find_child - find a profile on @head list using substring of @name
300 * @head: list to search (NOT NULL)
301 * @name: name of profile (NOT NULL)
302 * @len: length of @name substring to match
303 *
304 * Requires: rcu_read_lock be held
305 *
306 * Returns: unrefcounted profile ptr, or NULL if not found
307 */
308static struct aa_profile *__strn_find_child(struct list_head *head,
309 const char *name, int len)
310{
311 return (struct aa_profile *)__policy_strn_find(head, name, len);
312}
313
314/**
315 * __find_child - find a profile on @head list with a name matching @name
316 * @head: list to search (NOT NULL)
317 * @name: name of profile (NOT NULL)
318 *
319 * Requires: rcu_read_lock be held
320 *
321 * Returns: unrefcounted profile ptr, or NULL if not found
322 */
323static struct aa_profile *__find_child(struct list_head *head, const char *name)
324{
325 return __strn_find_child(head, name, strlen(name));
326}
327
328/**
329 * aa_find_child - find a profile by @name in @parent
330 * @parent: profile to search (NOT NULL)
331 * @name: profile name to search for (NOT NULL)
332 *
333 * Returns: a refcounted profile or NULL if not found
334 */
335struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name)
336{
337 struct aa_profile *profile;
338
339 rcu_read_lock();
340 do {
341 profile = __find_child(&parent->base.profiles, name);
342 } while (profile && !aa_get_profile_not0(profile));
343 rcu_read_unlock();
344
345 /* refcount released by caller */
346 return profile;
347}
348
349/**
350 * __lookup_parent - lookup the parent of a profile of name @hname
351 * @ns: namespace to lookup profile in (NOT NULL)
352 * @hname: hierarchical profile name to find parent of (NOT NULL)
353 *
354 * Lookups up the parent of a fully qualified profile name, the profile
355 * that matches hname does not need to exist, in general this
356 * is used to load a new profile.
357 *
358 * Requires: rcu_read_lock be held
359 *
360 * Returns: unrefcounted policy or NULL if not found
361 */
362static struct aa_policy *__lookup_parent(struct aa_ns *ns,
363 const char *hname)
364{
365 struct aa_policy *policy;
366 struct aa_profile *profile = NULL;
367 char *split;
368
369 policy = &ns->base;
370
371 for (split = strstr(hname, "//"); split;) {
372 profile = __strn_find_child(&policy->profiles, hname,
373 split - hname);
374 if (!profile)
375 return NULL;
376 policy = &profile->base;
377 hname = split + 2;
378 split = strstr(hname, "//");
379 }
380 if (!profile)
381 return &ns->base;
382 return &profile->base;
383}
384
385/**
386 * __lookupn_profile - lookup the profile matching @hname
387 * @base: base list to start looking up profile name from (NOT NULL)
388 * @hname: hierarchical profile name (NOT NULL)
389 * @n: length of @hname
390 *
391 * Requires: rcu_read_lock be held
392 *
393 * Returns: unrefcounted profile pointer or NULL if not found
394 *
395 * Do a relative name lookup, recursing through profile tree.
396 */
397static struct aa_profile *__lookupn_profile(struct aa_policy *base,
398 const char *hname, size_t n)
399{
400 struct aa_profile *profile = NULL;
401 const char *split;
402
403 for (split = strnstr(hname, "//", n); split;
404 split = strnstr(hname, "//", n)) {
405 profile = __strn_find_child(&base->profiles, hname,
406 split - hname);
407 if (!profile)
408 return NULL;
409
410 base = &profile->base;
411 n -= split + 2 - hname;
412 hname = split + 2;
413 }
414
415 if (n)
416 return __strn_find_child(&base->profiles, hname, n);
417 return NULL;
418}
419
420static struct aa_profile *__lookup_profile(struct aa_policy *base,
421 const char *hname)
422{
423 return __lookupn_profile(base, hname, strlen(hname));
424}
425
426/**
427 * aa_lookup_profile - find a profile by its full or partial name
428 * @ns: the namespace to start from (NOT NULL)
429 * @hname: name to do lookup on. Does not contain namespace prefix (NOT NULL)
430 * @n: size of @hname
431 *
432 * Returns: refcounted profile or NULL if not found
433 */
434struct aa_profile *aa_lookupn_profile(struct aa_ns *ns, const char *hname,
435 size_t n)
436{
437 struct aa_profile *profile;
438
439 rcu_read_lock();
440 do {
441 profile = __lookupn_profile(&ns->base, hname, n);
442 } while (profile && !aa_get_profile_not0(profile));
443 rcu_read_unlock();
444
445 /* the unconfined profile is not in the regular profile list */
446 if (!profile && strncmp(hname, "unconfined", n) == 0)
447 profile = aa_get_newest_profile(ns->unconfined);
448
449 /* refcount released by caller */
450 return profile;
451}
452
453struct aa_profile *aa_lookup_profile(struct aa_ns *ns, const char *hname)
454{
455 return aa_lookupn_profile(ns, hname, strlen(hname));
456}
457
458struct aa_profile *aa_fqlookupn_profile(struct aa_label *base,
459 const char *fqname, size_t n)
460{
461 struct aa_profile *profile;
462 struct aa_ns *ns;
463 const char *name, *ns_name;
464 size_t ns_len;
465
466 name = aa_splitn_fqname(fqname, n, &ns_name, &ns_len);
467 if (ns_name) {
468 ns = aa_lookupn_ns(labels_ns(base), ns_name, ns_len);
469 if (!ns)
470 return NULL;
471 } else
472 ns = aa_get_ns(labels_ns(base));
473
474 if (name)
475 profile = aa_lookupn_profile(ns, name, n - (name - fqname));
476 else if (ns)
477 /* default profile for ns, currently unconfined */
478 profile = aa_get_newest_profile(ns->unconfined);
479 else
480 profile = NULL;
481 aa_put_ns(ns);
482
483 return profile;
484}
485
486/**
487 * aa_new_null_profile - create or find a null-X learning profile
488 * @parent: profile that caused this profile to be created (NOT NULL)
489 * @hat: true if the null- learning profile is a hat
490 * @base: name to base the null profile off of
491 * @gfp: type of allocation
492 *
493 * Find/Create a null- complain mode profile used in learning mode. The
494 * name of the profile is unique and follows the format of parent//null-XXX.
495 * where XXX is based on the @name or if that fails or is not supplied
496 * a unique number
497 *
498 * null profiles are added to the profile list but the list does not
499 * hold a count on them so that they are automatically released when
500 * not in use.
501 *
502 * Returns: new refcounted profile else NULL on failure
503 */
504struct aa_profile *aa_new_null_profile(struct aa_profile *parent, bool hat,
505 const char *base, gfp_t gfp)
506{
507 struct aa_profile *p, *profile;
508 const char *bname;
509 char *name = NULL;
510
511 AA_BUG(!parent);
512
513 if (base) {
514 name = kmalloc(strlen(parent->base.hname) + 8 + strlen(base),
515 gfp);
516 if (name) {
517 sprintf(name, "%s//null-%s", parent->base.hname, base);
518 goto name;
519 }
520 /* fall through to try shorter uniq */
521 }
522
523 name = kmalloc(strlen(parent->base.hname) + 2 + 7 + 8, gfp);
524 if (!name)
525 return NULL;
526 sprintf(name, "%s//null-%x", parent->base.hname,
527 atomic_inc_return(&parent->ns->uniq_null));
528
529name:
530 /* lookup to see if this is a dup creation */
531 bname = basename(name);
532 profile = aa_find_child(parent, bname);
533 if (profile)
534 goto out;
535
536 profile = aa_alloc_profile(name, NULL, gfp);
537 if (!profile)
538 goto fail;
539
540 profile->mode = APPARMOR_COMPLAIN;
541 profile->label.flags |= FLAG_NULL;
542 if (hat)
543 profile->label.flags |= FLAG_HAT;
544 profile->path_flags = parent->path_flags;
545
546 /* released on free_profile */
547 rcu_assign_pointer(profile->parent, aa_get_profile(parent));
548 profile->ns = aa_get_ns(parent->ns);
549 profile->file.dfa = aa_get_dfa(nulldfa);
550 profile->policy.dfa = aa_get_dfa(nulldfa);
551
552 mutex_lock_nested(&profile->ns->lock, profile->ns->level);
553 p = __find_child(&parent->base.profiles, bname);
554 if (p) {
555 aa_free_profile(profile);
556 profile = aa_get_profile(p);
557 } else {
558 __add_profile(&parent->base.profiles, profile);
559 }
560 mutex_unlock(&profile->ns->lock);
561
562 /* refcount released by caller */
563out:
564 kfree(name);
565
566 return profile;
567
568fail:
569 kfree(name);
570 aa_free_profile(profile);
571 return NULL;
572}
573
574/**
575 * replacement_allowed - test to see if replacement is allowed
576 * @profile: profile to test if it can be replaced (MAYBE NULL)
577 * @noreplace: true if replacement shouldn't be allowed but addition is okay
578 * @info: Returns - info about why replacement failed (NOT NULL)
579 *
580 * Returns: %0 if replacement allowed else error code
581 */
582static int replacement_allowed(struct aa_profile *profile, int noreplace,
583 const char **info)
584{
585 if (profile) {
586 if (profile->label.flags & FLAG_IMMUTIBLE) {
587 *info = "cannot replace immutible profile";
588 return -EPERM;
589 } else if (noreplace) {
590 *info = "profile already exists";
591 return -EEXIST;
592 }
593 }
594 return 0;
595}
596
597/* audit callback for net specific fields */
598static void audit_cb(struct audit_buffer *ab, void *va)
599{
600 struct common_audit_data *sa = va;
601
602 if (aad(sa)->iface.ns) {
603 audit_log_format(ab, " ns=");
604 audit_log_untrustedstring(ab, aad(sa)->iface.ns);
605 }
606}
607
608/**
609 * audit_policy - Do auditing of policy changes
610 * @label: label to check if it can manage policy
611 * @op: policy operation being performed
612 * @ns_name: name of namespace being manipulated
613 * @name: name of profile being manipulated (NOT NULL)
614 * @info: any extra information to be audited (MAYBE NULL)
615 * @error: error code
616 *
617 * Returns: the error to be returned after audit is done
618 */
619static int audit_policy(struct aa_label *label, const char *op,
620 const char *ns_name, const char *name,
621 const char *info, int error)
622{
623 DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, op);
624
625 aad(&sa)->iface.ns = ns_name;
626 aad(&sa)->name = name;
627 aad(&sa)->info = info;
628 aad(&sa)->error = error;
629 aad(&sa)->label = label;
630
631 aa_audit_msg(AUDIT_APPARMOR_STATUS, &sa, audit_cb);
632
633 return error;
634}
635
636/**
637 * policy_view_capable - check if viewing policy in at @ns is allowed
638 * ns: namespace being viewed by current task (may be NULL)
639 * Returns: true if viewing policy is allowed
640 *
641 * If @ns is NULL then the namespace being viewed is assumed to be the
642 * tasks current namespace.
643 */
644bool policy_view_capable(struct aa_ns *ns)
645{
646 struct user_namespace *user_ns = current_user_ns();
647 struct aa_ns *view_ns = aa_get_current_ns();
648 bool root_in_user_ns = uid_eq(current_euid(), make_kuid(user_ns, 0)) ||
649 in_egroup_p(make_kgid(user_ns, 0));
650 bool response = false;
651 if (!ns)
652 ns = view_ns;
653
654 if (root_in_user_ns && aa_ns_visible(view_ns, ns, true) &&
655 (user_ns == &init_user_ns ||
656 (unprivileged_userns_apparmor_policy != 0 &&
657 user_ns->level == view_ns->level)))
658 response = true;
659 aa_put_ns(view_ns);
660
661 return response;
662}
663
664bool policy_admin_capable(struct aa_ns *ns)
665{
666 struct user_namespace *user_ns = current_user_ns();
667 bool capable = ns_capable(user_ns, CAP_MAC_ADMIN);
668
669 AA_DEBUG("cap_mac_admin? %d\n", capable);
670 AA_DEBUG("policy locked? %d\n", aa_g_lock_policy);
671
672 return policy_view_capable(ns) && capable && !aa_g_lock_policy;
673}
674
675/**
676 * aa_may_manage_policy - can the current task manage policy
677 * @label: label to check if it can manage policy
678 * @op: the policy manipulation operation being done
679 *
680 * Returns: 0 if the task is allowed to manipulate policy else error
681 */
682int aa_may_manage_policy(struct aa_label *label, struct aa_ns *ns, u32 mask)
683{
684 const char *op;
685
686 if (mask & AA_MAY_REMOVE_POLICY)
687 op = OP_PROF_RM;
688 else if (mask & AA_MAY_REPLACE_POLICY)
689 op = OP_PROF_REPL;
690 else
691 op = OP_PROF_LOAD;
692
693 /* check if loading policy is locked out */
694 if (aa_g_lock_policy)
695 return audit_policy(label, op, NULL, NULL, "policy_locked",
696 -EACCES);
697
698 if (!policy_admin_capable(ns))
699 return audit_policy(label, op, NULL, NULL, "not policy admin",
700 -EACCES);
701
702 /* TODO: add fine grained mediation of policy loads */
703 return 0;
704}
705
706static struct aa_profile *__list_lookup_parent(struct list_head *lh,
707 struct aa_profile *profile)
708{
709 const char *base = basename(profile->base.hname);
710 long len = base - profile->base.hname;
711 struct aa_load_ent *ent;
712
713 /* parent won't have trailing // so remove from len */
714 if (len <= 2)
715 return NULL;
716 len -= 2;
717
718 list_for_each_entry(ent, lh, list) {
719 if (ent->new == profile)
720 continue;
721 if (strncmp(ent->new->base.hname, profile->base.hname, len) ==
722 0 && ent->new->base.hname[len] == 0)
723 return ent->new;
724 }
725
726 return NULL;
727}
728
729/**
730 * __replace_profile - replace @old with @new on a list
731 * @old: profile to be replaced (NOT NULL)
732 * @new: profile to replace @old with (NOT NULL)
733 * @share_proxy: transfer @old->proxy to @new
734 *
735 * Will duplicate and refcount elements that @new inherits from @old
736 * and will inherit @old children.
737 *
738 * refcount @new for list, put @old list refcount
739 *
740 * Requires: namespace list lock be held, or list not be shared
741 */
742static void __replace_profile(struct aa_profile *old, struct aa_profile *new)
743{
744 struct aa_profile *child, *tmp;
745
746 if (!list_empty(&old->base.profiles)) {
747 LIST_HEAD(lh);
748 list_splice_init_rcu(&old->base.profiles, &lh, synchronize_rcu);
749
750 list_for_each_entry_safe(child, tmp, &lh, base.list) {
751 struct aa_profile *p;
752
753 list_del_init(&child->base.list);
754 p = __find_child(&new->base.profiles, child->base.name);
755 if (p) {
756 /* @p replaces @child */
757 __replace_profile(child, p);
758 continue;
759 }
760
761 /* inherit @child and its children */
762 /* TODO: update hname of inherited children */
763 /* list refcount transferred to @new */
764 p = aa_deref_parent(child);
765 rcu_assign_pointer(child->parent, aa_get_profile(new));
766 list_add_rcu(&child->base.list, &new->base.profiles);
767 aa_put_profile(p);
768 }
769 }
770
771 if (!rcu_access_pointer(new->parent)) {
772 struct aa_profile *parent = aa_deref_parent(old);
773 rcu_assign_pointer(new->parent, aa_get_profile(parent));
774 }
775 aa_label_replace(&old->label, &new->label);
776 /* migrate dents must come after label replacement b/c update */
777 __aafs_profile_migrate_dents(old, new);
778
779 if (list_empty(&new->base.list)) {
780 /* new is not on a list already */
781 list_replace_rcu(&old->base.list, &new->base.list);
782 aa_get_profile(new);
783 aa_put_profile(old);
784 } else
785 __list_remove_profile(old);
786}
787
788/**
789 * __lookup_replace - lookup replacement information for a profile
790 * @ns - namespace the lookup occurs in
791 * @hname - name of profile to lookup
792 * @noreplace - true if not replacing an existing profile
793 * @p - Returns: profile to be replaced
794 * @info - Returns: info string on why lookup failed
795 *
796 * Returns: profile to replace (no ref) on success else ptr error
797 */
798static int __lookup_replace(struct aa_ns *ns, const char *hname,
799 bool noreplace, struct aa_profile **p,
800 const char **info)
801{
802 *p = aa_get_profile(__lookup_profile(&ns->base, hname));
803 if (*p) {
804 int error = replacement_allowed(*p, noreplace, info);
805 if (error) {
806 *info = "profile can not be replaced";
807 return error;
808 }
809 }
810
811 return 0;
812}
813
814static void share_name(struct aa_profile *old, struct aa_profile *new)
815{
816 aa_put_str(new->base.hname);
817 aa_get_str(old->base.hname);
818 new->base.hname = old->base.hname;
819 new->base.name = old->base.name;
820 new->label.hname = old->label.hname;
821}
822
823/* Update to newest version of parent after previous replacements
824 * Returns: unrefcount newest version of parent
825 */
826static struct aa_profile *update_to_newest_parent(struct aa_profile *new)
827{
828 struct aa_profile *parent, *newest;
829
830 parent = rcu_dereference_protected(new->parent,
831 mutex_is_locked(&new->ns->lock));
832 newest = aa_get_newest_profile(parent);
833
834 /* parent replaced in this atomic set? */
835 if (newest != parent) {
836 aa_put_profile(parent);
837 rcu_assign_pointer(new->parent, newest);
838 } else
839 aa_put_profile(newest);
840
841 return newest;
842}
843
844/**
845 * aa_replace_profiles - replace profile(s) on the profile list
846 * @policy_ns: namespace load is occurring on
847 * @label: label that is attempting to load/replace policy
848 * @mask: permission mask
849 * @udata: serialized data stream (NOT NULL)
850 *
851 * unpack and replace a profile on the profile list and uses of that profile
852 * by any task creds via invalidating the old version of the profile, which
853 * tasks will notice to update their own cred. If the profile does not exist
854 * on the profile list it is added.
855 *
856 * Returns: size of data consumed else error code on failure.
857 */
858ssize_t aa_replace_profiles(struct aa_ns *policy_ns, struct aa_label *label,
859 u32 mask, struct aa_loaddata *udata)
860{
861 const char *ns_name, *info = NULL;
862 struct aa_ns *ns = NULL;
863 struct aa_load_ent *ent, *tmp;
864 struct aa_loaddata *rawdata_ent;
865 const char *op;
866 ssize_t count, error;
867 LIST_HEAD(lh);
868
869 op = mask & AA_MAY_REPLACE_POLICY ? OP_PROF_REPL : OP_PROF_LOAD;
870 aa_get_loaddata(udata);
871 /* released below */
872 error = aa_unpack(udata, &lh, &ns_name);
873 if (error)
874 goto out;
875
876 /* ensure that profiles are all for the same ns
877 * TODO: update locking to remove this constaint. All profiles in
878 * the load set must succeed as a set or the load will
879 * fail. Sort ent list and take ns locks in hierarchy order
880 */
881 count = 0;
882 list_for_each_entry(ent, &lh, list) {
883 if (ns_name) {
884 if (ent->ns_name &&
885 strcmp(ent->ns_name, ns_name) != 0) {
886 info = "policy load has mixed namespaces";
887 error = -EACCES;
888 goto fail;
889 }
890 } else if (ent->ns_name) {
891 if (count) {
892 info = "policy load has mixed namespaces";
893 error = -EACCES;
894 goto fail;
895 }
896 ns_name = ent->ns_name;
897 } else
898 count++;
899 }
900 if (ns_name) {
901 ns = aa_prepare_ns(policy_ns ? policy_ns : labels_ns(label),
902 ns_name);
903 if (IS_ERR(ns)) {
904 op = OP_PROF_LOAD;
905 info = "failed to prepare namespace";
906 error = PTR_ERR(ns);
907 ns = NULL;
908 ent = NULL;
909 goto fail;
910 }
911 } else
912 ns = aa_get_ns(policy_ns ? policy_ns : labels_ns(label));
913
914 mutex_lock_nested(&ns->lock, ns->level);
915 /* check for duplicate rawdata blobs: space and file dedup */
916 list_for_each_entry(rawdata_ent, &ns->rawdata_list, list) {
917 if (aa_rawdata_eq(rawdata_ent, udata)) {
918 struct aa_loaddata *tmp;
919
920 tmp = __aa_get_loaddata(rawdata_ent);
921 /* check we didn't fail the race */
922 if (tmp) {
923 aa_put_loaddata(udata);
924 udata = tmp;
925 break;
926 }
927 }
928 }
929 /* setup parent and ns info */
930 list_for_each_entry(ent, &lh, list) {
931 struct aa_policy *policy;
932
933 ent->new->rawdata = aa_get_loaddata(udata);
934 error = __lookup_replace(ns, ent->new->base.hname,
935 !(mask & AA_MAY_REPLACE_POLICY),
936 &ent->old, &info);
937 if (error)
938 goto fail_lock;
939
940 if (ent->new->rename) {
941 error = __lookup_replace(ns, ent->new->rename,
942 !(mask & AA_MAY_REPLACE_POLICY),
943 &ent->rename, &info);
944 if (error)
945 goto fail_lock;
946 }
947
948 /* released when @new is freed */
949 ent->new->ns = aa_get_ns(ns);
950
951 if (ent->old || ent->rename)
952 continue;
953
954 /* no ref on policy only use inside lock */
955 policy = __lookup_parent(ns, ent->new->base.hname);
956 if (!policy) {
957 struct aa_profile *p;
958 p = __list_lookup_parent(&lh, ent->new);
959 if (!p) {
960 error = -ENOENT;
961 info = "parent does not exist";
962 goto fail_lock;
963 }
964 rcu_assign_pointer(ent->new->parent, aa_get_profile(p));
965 } else if (policy != &ns->base) {
966 /* released on profile replacement or free_profile */
967 struct aa_profile *p = (struct aa_profile *) policy;
968 rcu_assign_pointer(ent->new->parent, aa_get_profile(p));
969 }
970 }
971
972 /* create new fs entries for introspection if needed */
973 if (!udata->dents[AAFS_LOADDATA_DIR]) {
974 error = __aa_fs_create_rawdata(ns, udata);
975 if (error) {
976 info = "failed to create raw_data dir and files";
977 ent = NULL;
978 goto fail_lock;
979 }
980 }
981 list_for_each_entry(ent, &lh, list) {
982 if (!ent->old) {
983 struct dentry *parent;
984 if (rcu_access_pointer(ent->new->parent)) {
985 struct aa_profile *p;
986 p = aa_deref_parent(ent->new);
987 parent = prof_child_dir(p);
988 } else
989 parent = ns_subprofs_dir(ent->new->ns);
990 error = __aafs_profile_mkdir(ent->new, parent);
991 }
992
993 if (error) {
994 info = "failed to create";
995 goto fail_lock;
996 }
997 }
998
999 /* Done with checks that may fail - do actual replacement */
1000 __aa_bump_ns_revision(ns);
1001 __aa_loaddata_update(udata, ns->revision);
1002 list_for_each_entry_safe(ent, tmp, &lh, list) {
1003 list_del_init(&ent->list);
1004 op = (!ent->old && !ent->rename) ? OP_PROF_LOAD : OP_PROF_REPL;
1005
1006 if (ent->old && ent->old->rawdata == ent->new->rawdata) {
1007 /* dedup actual profile replacement */
1008 audit_policy(label, op, ns_name, ent->new->base.hname,
1009 "same as current profile, skipping",
1010 error);
1011 goto skip;
1012 }
1013
1014 /*
1015 * TODO: finer dedup based on profile range in data. Load set
1016 * can differ but profile may remain unchanged
1017 */
1018 audit_policy(label, op, ns_name, ent->new->base.hname, NULL,
1019 error);
1020
1021 if (ent->old) {
1022 share_name(ent->old, ent->new);
1023 __replace_profile(ent->old, ent->new);
1024 } else {
1025 struct list_head *lh;
1026
1027 if (rcu_access_pointer(ent->new->parent)) {
1028 struct aa_profile *parent;
1029
1030 parent = update_to_newest_parent(ent->new);
1031 lh = &parent->base.profiles;
1032 } else
1033 lh = &ns->base.profiles;
1034 __add_profile(lh, ent->new);
1035 }
1036 skip:
1037 aa_load_ent_free(ent);
1038 }
1039 __aa_labelset_update_subtree(ns);
1040 mutex_unlock(&ns->lock);
1041
1042out:
1043 aa_put_ns(ns);
1044 aa_put_loaddata(udata);
1045
1046 if (error)
1047 return error;
1048 return udata->size;
1049
1050fail_lock:
1051 mutex_unlock(&ns->lock);
1052
1053 /* audit cause of failure */
1054 op = (ent && !ent->old) ? OP_PROF_LOAD : OP_PROF_REPL;
1055fail:
1056 audit_policy(label, op, ns_name, ent ? ent->new->base.hname : NULL,
1057 info, error);
1058 /* audit status that rest of profiles in the atomic set failed too */
1059 info = "valid profile in failed atomic policy load";
1060 list_for_each_entry(tmp, &lh, list) {
1061 if (tmp == ent) {
1062 info = "unchecked profile in failed atomic policy load";
1063 /* skip entry that caused failure */
1064 continue;
1065 }
1066 op = (!tmp->old) ? OP_PROF_LOAD : OP_PROF_REPL;
1067 audit_policy(label, op, ns_name, tmp->new->base.hname, info,
1068 error);
1069 }
1070 list_for_each_entry_safe(ent, tmp, &lh, list) {
1071 list_del_init(&ent->list);
1072 aa_load_ent_free(ent);
1073 }
1074
1075 goto out;
1076}
1077
1078/**
1079 * aa_remove_profiles - remove profile(s) from the system
1080 * @policy_ns: namespace the remove is being done from
1081 * @subj: label attempting to remove policy
1082 * @fqname: name of the profile or namespace to remove (NOT NULL)
1083 * @size: size of the name
1084 *
1085 * Remove a profile or sub namespace from the current namespace, so that
1086 * they can not be found anymore and mark them as replaced by unconfined
1087 *
1088 * NOTE: removing confinement does not restore rlimits to preconfinemnet values
1089 *
1090 * Returns: size of data consume else error code if fails
1091 */
1092ssize_t aa_remove_profiles(struct aa_ns *policy_ns, struct aa_label *subj,
1093 char *fqname, size_t size)
1094{
1095 struct aa_ns *ns = NULL;
1096 struct aa_profile *profile = NULL;
1097 const char *name = fqname, *info = NULL;
1098 const char *ns_name = NULL;
1099 ssize_t error = 0;
1100
1101 if (*fqname == 0) {
1102 info = "no profile specified";
1103 error = -ENOENT;
1104 goto fail;
1105 }
1106
1107 if (fqname[0] == ':') {
1108 size_t ns_len;
1109
1110 name = aa_splitn_fqname(fqname, size, &ns_name, &ns_len);
1111 /* released below */
1112 ns = aa_lookupn_ns(policy_ns ? policy_ns : labels_ns(subj),
1113 ns_name, ns_len);
1114 if (!ns) {
1115 info = "namespace does not exist";
1116 error = -ENOENT;
1117 goto fail;
1118 }
1119 } else
1120 /* released below */
1121 ns = aa_get_ns(policy_ns ? policy_ns : labels_ns(subj));
1122
1123 if (!name) {
1124 /* remove namespace - can only happen if fqname[0] == ':' */
1125 mutex_lock_nested(&ns->parent->lock, ns->level);
1126 __aa_remove_ns(ns);
1127 __aa_bump_ns_revision(ns);
1128 mutex_unlock(&ns->parent->lock);
1129 } else {
1130 /* remove profile */
1131 mutex_lock_nested(&ns->lock, ns->level);
1132 profile = aa_get_profile(__lookup_profile(&ns->base, name));
1133 if (!profile) {
1134 error = -ENOENT;
1135 info = "profile does not exist";
1136 goto fail_ns_lock;
1137 }
1138 name = profile->base.hname;
1139 __remove_profile(profile);
1140 __aa_labelset_update_subtree(ns);
1141 __aa_bump_ns_revision(ns);
1142 mutex_unlock(&ns->lock);
1143 }
1144
1145 /* don't fail removal if audit fails */
1146 (void) audit_policy(subj, OP_PROF_RM, ns_name, name, info,
1147 error);
1148 aa_put_ns(ns);
1149 aa_put_profile(profile);
1150 return size;
1151
1152fail_ns_lock:
1153 mutex_unlock(&ns->lock);
1154 aa_put_ns(ns);
1155
1156fail:
1157 (void) audit_policy(subj, OP_PROF_RM, ns_name, name, info,
1158 error);
1159 return error;
1160}
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * AppArmor security module
4 *
5 * This file contains AppArmor policy manipulation functions
6 *
7 * Copyright (C) 1998-2008 Novell/SUSE
8 * Copyright 2009-2010 Canonical Ltd.
9 *
10 * AppArmor policy is based around profiles, which contain the rules a
11 * task is confined by. Every task in the system has a profile attached
12 * to it determined either by matching "unconfined" tasks against the
13 * visible set of profiles or by following a profiles attachment rules.
14 *
15 * Each profile exists in a profile namespace which is a container of
16 * visible profiles. Each namespace contains a special "unconfined" profile,
17 * which doesn't enforce any confinement on a task beyond DAC.
18 *
19 * Namespace and profile names can be written together in either
20 * of two syntaxes.
21 * :namespace:profile - used by kernel interfaces for easy detection
22 * namespace://profile - used by policy
23 *
24 * Profile names can not start with : or @ or ^ and may not contain \0
25 *
26 * Reserved profile names
27 * unconfined - special automatically generated unconfined profile
28 * inherit - special name to indicate profile inheritance
29 * null-XXXX-YYYY - special automatically generated learning profiles
30 *
31 * Namespace names may not start with / or @ and may not contain \0 or :
32 * Reserved namespace names
33 * user-XXXX - user defined profiles
34 *
35 * a // in a profile or namespace name indicates a hierarchical name with the
36 * name before the // being the parent and the name after the child.
37 *
38 * Profile and namespace hierarchies serve two different but similar purposes.
39 * The namespace contains the set of visible profiles that are considered
40 * for attachment. The hierarchy of namespaces allows for virtualizing
41 * the namespace so that for example a chroot can have its own set of profiles
42 * which may define some local user namespaces.
43 * The profile hierarchy severs two distinct purposes,
44 * - it allows for sub profiles or hats, which allows an application to run
45 * subprograms under its own profile with different restriction than it
46 * self, and not have it use the system profile.
47 * eg. if a mail program starts an editor, the policy might make the
48 * restrictions tighter on the editor tighter than the mail program,
49 * and definitely different than general editor restrictions
50 * - it allows for binary hierarchy of profiles, so that execution history
51 * is preserved. This feature isn't exploited by AppArmor reference policy
52 * but is allowed. NOTE: this is currently suboptimal because profile
53 * aliasing is not currently implemented so that a profile for each
54 * level must be defined.
55 * eg. /bin/bash///bin/ls as a name would indicate /bin/ls was started
56 * from /bin/bash
57 *
58 * A profile or namespace name that can contain one or more // separators
59 * is referred to as an hname (hierarchical).
60 * eg. /bin/bash//bin/ls
61 *
62 * An fqname is a name that may contain both namespace and profile hnames.
63 * eg. :ns:/bin/bash//bin/ls
64 *
65 * NOTES:
66 * - locking of profile lists is currently fairly coarse. All profile
67 * lists within a namespace use the namespace lock.
68 * FIXME: move profile lists to using rcu_lists
69 */
70
71#include <linux/slab.h>
72#include <linux/spinlock.h>
73#include <linux/string.h>
74#include <linux/cred.h>
75#include <linux/rculist.h>
76#include <linux/user_namespace.h>
77
78#include "include/apparmor.h"
79#include "include/capability.h"
80#include "include/cred.h"
81#include "include/file.h"
82#include "include/ipc.h"
83#include "include/match.h"
84#include "include/path.h"
85#include "include/policy.h"
86#include "include/policy_ns.h"
87#include "include/policy_unpack.h"
88#include "include/resource.h"
89
90int unprivileged_userns_apparmor_policy = 1;
91
92const char *const aa_profile_mode_names[] = {
93 "enforce",
94 "complain",
95 "kill",
96 "unconfined",
97};
98
99
100/**
101 * __add_profile - add a profiles to list and label tree
102 * @list: list to add it to (NOT NULL)
103 * @profile: the profile to add (NOT NULL)
104 *
105 * refcount @profile, should be put by __list_remove_profile
106 *
107 * Requires: namespace lock be held, or list not be shared
108 */
109static void __add_profile(struct list_head *list, struct aa_profile *profile)
110{
111 struct aa_label *l;
112
113 AA_BUG(!list);
114 AA_BUG(!profile);
115 AA_BUG(!profile->ns);
116 AA_BUG(!mutex_is_locked(&profile->ns->lock));
117
118 list_add_rcu(&profile->base.list, list);
119 /* get list reference */
120 aa_get_profile(profile);
121 l = aa_label_insert(&profile->ns->labels, &profile->label);
122 AA_BUG(l != &profile->label);
123 aa_put_label(l);
124}
125
126/**
127 * __list_remove_profile - remove a profile from the list it is on
128 * @profile: the profile to remove (NOT NULL)
129 *
130 * remove a profile from the list, warning generally removal should
131 * be done with __replace_profile as most profile removals are
132 * replacements to the unconfined profile.
133 *
134 * put @profile list refcount
135 *
136 * Requires: namespace lock be held, or list not have been live
137 */
138static void __list_remove_profile(struct aa_profile *profile)
139{
140 AA_BUG(!profile);
141 AA_BUG(!profile->ns);
142 AA_BUG(!mutex_is_locked(&profile->ns->lock));
143
144 list_del_rcu(&profile->base.list);
145 aa_put_profile(profile);
146}
147
148/**
149 * __remove_profile - remove old profile, and children
150 * @profile: profile to be replaced (NOT NULL)
151 *
152 * Requires: namespace list lock be held, or list not be shared
153 */
154static void __remove_profile(struct aa_profile *profile)
155{
156 AA_BUG(!profile);
157 AA_BUG(!profile->ns);
158 AA_BUG(!mutex_is_locked(&profile->ns->lock));
159
160 /* release any children lists first */
161 __aa_profile_list_release(&profile->base.profiles);
162 /* released by free_profile */
163 aa_label_remove(&profile->label);
164 __aafs_profile_rmdir(profile);
165 __list_remove_profile(profile);
166}
167
168/**
169 * __aa_profile_list_release - remove all profiles on the list and put refs
170 * @head: list of profiles (NOT NULL)
171 *
172 * Requires: namespace lock be held
173 */
174void __aa_profile_list_release(struct list_head *head)
175{
176 struct aa_profile *profile, *tmp;
177 list_for_each_entry_safe(profile, tmp, head, base.list)
178 __remove_profile(profile);
179}
180
181/**
182 * aa_free_data - free a data blob
183 * @ptr: data to free
184 * @arg: unused
185 */
186static void aa_free_data(void *ptr, void *arg)
187{
188 struct aa_data *data = ptr;
189
190 kfree_sensitive(data->data);
191 kfree_sensitive(data->key);
192 kfree_sensitive(data);
193}
194
195/**
196 * aa_free_profile - free a profile
197 * @profile: the profile to free (MAYBE NULL)
198 *
199 * Free a profile, its hats and null_profile. All references to the profile,
200 * its hats and null_profile must have been put.
201 *
202 * If the profile was referenced from a task context, free_profile() will
203 * be called from an rcu callback routine, so we must not sleep here.
204 */
205void aa_free_profile(struct aa_profile *profile)
206{
207 struct rhashtable *rht;
208 int i;
209
210 AA_DEBUG("%s(%p)\n", __func__, profile);
211
212 if (!profile)
213 return;
214
215 /* free children profiles */
216 aa_policy_destroy(&profile->base);
217 aa_put_profile(rcu_access_pointer(profile->parent));
218
219 aa_put_ns(profile->ns);
220 kfree_sensitive(profile->rename);
221
222 aa_free_file_rules(&profile->file);
223 aa_free_cap_rules(&profile->caps);
224 aa_free_rlimit_rules(&profile->rlimits);
225
226 for (i = 0; i < profile->xattr_count; i++)
227 kfree_sensitive(profile->xattrs[i]);
228 kfree_sensitive(profile->xattrs);
229 for (i = 0; i < profile->secmark_count; i++)
230 kfree_sensitive(profile->secmark[i].label);
231 kfree_sensitive(profile->secmark);
232 kfree_sensitive(profile->dirname);
233 aa_put_dfa(profile->xmatch);
234 aa_put_dfa(profile->policy.dfa);
235
236 if (profile->data) {
237 rht = profile->data;
238 profile->data = NULL;
239 rhashtable_free_and_destroy(rht, aa_free_data, NULL);
240 kfree_sensitive(rht);
241 }
242
243 kfree_sensitive(profile->hash);
244 aa_put_loaddata(profile->rawdata);
245 aa_label_destroy(&profile->label);
246
247 kfree_sensitive(profile);
248}
249
250/**
251 * aa_alloc_profile - allocate, initialize and return a new profile
252 * @hname: name of the profile (NOT NULL)
253 * @gfp: allocation type
254 *
255 * Returns: refcount profile or NULL on failure
256 */
257struct aa_profile *aa_alloc_profile(const char *hname, struct aa_proxy *proxy,
258 gfp_t gfp)
259{
260 struct aa_profile *profile;
261
262 /* freed by free_profile - usually through aa_put_profile */
263 profile = kzalloc(sizeof(*profile) + sizeof(struct aa_profile *) * 2,
264 gfp);
265 if (!profile)
266 return NULL;
267
268 if (!aa_policy_init(&profile->base, NULL, hname, gfp))
269 goto fail;
270 if (!aa_label_init(&profile->label, 1, gfp))
271 goto fail;
272
273 /* update being set needed by fs interface */
274 if (!proxy) {
275 proxy = aa_alloc_proxy(&profile->label, gfp);
276 if (!proxy)
277 goto fail;
278 } else
279 aa_get_proxy(proxy);
280 profile->label.proxy = proxy;
281
282 profile->label.hname = profile->base.hname;
283 profile->label.flags |= FLAG_PROFILE;
284 profile->label.vec[0] = profile;
285
286 /* refcount released by caller */
287 return profile;
288
289fail:
290 aa_free_profile(profile);
291
292 return NULL;
293}
294
295/* TODO: profile accounting - setup in remove */
296
297/**
298 * __strn_find_child - find a profile on @head list using substring of @name
299 * @head: list to search (NOT NULL)
300 * @name: name of profile (NOT NULL)
301 * @len: length of @name substring to match
302 *
303 * Requires: rcu_read_lock be held
304 *
305 * Returns: unrefcounted profile ptr, or NULL if not found
306 */
307static struct aa_profile *__strn_find_child(struct list_head *head,
308 const char *name, int len)
309{
310 return (struct aa_profile *)__policy_strn_find(head, name, len);
311}
312
313/**
314 * __find_child - find a profile on @head list with a name matching @name
315 * @head: list to search (NOT NULL)
316 * @name: name of profile (NOT NULL)
317 *
318 * Requires: rcu_read_lock be held
319 *
320 * Returns: unrefcounted profile ptr, or NULL if not found
321 */
322static struct aa_profile *__find_child(struct list_head *head, const char *name)
323{
324 return __strn_find_child(head, name, strlen(name));
325}
326
327/**
328 * aa_find_child - find a profile by @name in @parent
329 * @parent: profile to search (NOT NULL)
330 * @name: profile name to search for (NOT NULL)
331 *
332 * Returns: a refcounted profile or NULL if not found
333 */
334struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name)
335{
336 struct aa_profile *profile;
337
338 rcu_read_lock();
339 do {
340 profile = __find_child(&parent->base.profiles, name);
341 } while (profile && !aa_get_profile_not0(profile));
342 rcu_read_unlock();
343
344 /* refcount released by caller */
345 return profile;
346}
347
348/**
349 * __lookup_parent - lookup the parent of a profile of name @hname
350 * @ns: namespace to lookup profile in (NOT NULL)
351 * @hname: hierarchical profile name to find parent of (NOT NULL)
352 *
353 * Lookups up the parent of a fully qualified profile name, the profile
354 * that matches hname does not need to exist, in general this
355 * is used to load a new profile.
356 *
357 * Requires: rcu_read_lock be held
358 *
359 * Returns: unrefcounted policy or NULL if not found
360 */
361static struct aa_policy *__lookup_parent(struct aa_ns *ns,
362 const char *hname)
363{
364 struct aa_policy *policy;
365 struct aa_profile *profile = NULL;
366 char *split;
367
368 policy = &ns->base;
369
370 for (split = strstr(hname, "//"); split;) {
371 profile = __strn_find_child(&policy->profiles, hname,
372 split - hname);
373 if (!profile)
374 return NULL;
375 policy = &profile->base;
376 hname = split + 2;
377 split = strstr(hname, "//");
378 }
379 if (!profile)
380 return &ns->base;
381 return &profile->base;
382}
383
384/**
385 * __lookupn_profile - lookup the profile matching @hname
386 * @base: base list to start looking up profile name from (NOT NULL)
387 * @hname: hierarchical profile name (NOT NULL)
388 * @n: length of @hname
389 *
390 * Requires: rcu_read_lock be held
391 *
392 * Returns: unrefcounted profile pointer or NULL if not found
393 *
394 * Do a relative name lookup, recursing through profile tree.
395 */
396static struct aa_profile *__lookupn_profile(struct aa_policy *base,
397 const char *hname, size_t n)
398{
399 struct aa_profile *profile = NULL;
400 const char *split;
401
402 for (split = strnstr(hname, "//", n); split;
403 split = strnstr(hname, "//", n)) {
404 profile = __strn_find_child(&base->profiles, hname,
405 split - hname);
406 if (!profile)
407 return NULL;
408
409 base = &profile->base;
410 n -= split + 2 - hname;
411 hname = split + 2;
412 }
413
414 if (n)
415 return __strn_find_child(&base->profiles, hname, n);
416 return NULL;
417}
418
419static struct aa_profile *__lookup_profile(struct aa_policy *base,
420 const char *hname)
421{
422 return __lookupn_profile(base, hname, strlen(hname));
423}
424
425/**
426 * aa_lookup_profile - find a profile by its full or partial name
427 * @ns: the namespace to start from (NOT NULL)
428 * @hname: name to do lookup on. Does not contain namespace prefix (NOT NULL)
429 * @n: size of @hname
430 *
431 * Returns: refcounted profile or NULL if not found
432 */
433struct aa_profile *aa_lookupn_profile(struct aa_ns *ns, const char *hname,
434 size_t n)
435{
436 struct aa_profile *profile;
437
438 rcu_read_lock();
439 do {
440 profile = __lookupn_profile(&ns->base, hname, n);
441 } while (profile && !aa_get_profile_not0(profile));
442 rcu_read_unlock();
443
444 /* the unconfined profile is not in the regular profile list */
445 if (!profile && strncmp(hname, "unconfined", n) == 0)
446 profile = aa_get_newest_profile(ns->unconfined);
447
448 /* refcount released by caller */
449 return profile;
450}
451
452struct aa_profile *aa_lookup_profile(struct aa_ns *ns, const char *hname)
453{
454 return aa_lookupn_profile(ns, hname, strlen(hname));
455}
456
457struct aa_profile *aa_fqlookupn_profile(struct aa_label *base,
458 const char *fqname, size_t n)
459{
460 struct aa_profile *profile;
461 struct aa_ns *ns;
462 const char *name, *ns_name;
463 size_t ns_len;
464
465 name = aa_splitn_fqname(fqname, n, &ns_name, &ns_len);
466 if (ns_name) {
467 ns = aa_lookupn_ns(labels_ns(base), ns_name, ns_len);
468 if (!ns)
469 return NULL;
470 } else
471 ns = aa_get_ns(labels_ns(base));
472
473 if (name)
474 profile = aa_lookupn_profile(ns, name, n - (name - fqname));
475 else if (ns)
476 /* default profile for ns, currently unconfined */
477 profile = aa_get_newest_profile(ns->unconfined);
478 else
479 profile = NULL;
480 aa_put_ns(ns);
481
482 return profile;
483}
484
485/**
486 * aa_new_null_profile - create or find a null-X learning profile
487 * @parent: profile that caused this profile to be created (NOT NULL)
488 * @hat: true if the null- learning profile is a hat
489 * @base: name to base the null profile off of
490 * @gfp: type of allocation
491 *
492 * Find/Create a null- complain mode profile used in learning mode. The
493 * name of the profile is unique and follows the format of parent//null-XXX.
494 * where XXX is based on the @name or if that fails or is not supplied
495 * a unique number
496 *
497 * null profiles are added to the profile list but the list does not
498 * hold a count on them so that they are automatically released when
499 * not in use.
500 *
501 * Returns: new refcounted profile else NULL on failure
502 */
503struct aa_profile *aa_new_null_profile(struct aa_profile *parent, bool hat,
504 const char *base, gfp_t gfp)
505{
506 struct aa_profile *p, *profile;
507 const char *bname;
508 char *name = NULL;
509
510 AA_BUG(!parent);
511
512 if (base) {
513 name = kmalloc(strlen(parent->base.hname) + 8 + strlen(base),
514 gfp);
515 if (name) {
516 sprintf(name, "%s//null-%s", parent->base.hname, base);
517 goto name;
518 }
519 /* fall through to try shorter uniq */
520 }
521
522 name = kmalloc(strlen(parent->base.hname) + 2 + 7 + 8, gfp);
523 if (!name)
524 return NULL;
525 sprintf(name, "%s//null-%x", parent->base.hname,
526 atomic_inc_return(&parent->ns->uniq_null));
527
528name:
529 /* lookup to see if this is a dup creation */
530 bname = basename(name);
531 profile = aa_find_child(parent, bname);
532 if (profile)
533 goto out;
534
535 profile = aa_alloc_profile(name, NULL, gfp);
536 if (!profile)
537 goto fail;
538
539 profile->mode = APPARMOR_COMPLAIN;
540 profile->label.flags |= FLAG_NULL;
541 if (hat)
542 profile->label.flags |= FLAG_HAT;
543 profile->path_flags = parent->path_flags;
544
545 /* released on free_profile */
546 rcu_assign_pointer(profile->parent, aa_get_profile(parent));
547 profile->ns = aa_get_ns(parent->ns);
548 profile->file.dfa = aa_get_dfa(nulldfa);
549 profile->policy.dfa = aa_get_dfa(nulldfa);
550
551 mutex_lock_nested(&profile->ns->lock, profile->ns->level);
552 p = __find_child(&parent->base.profiles, bname);
553 if (p) {
554 aa_free_profile(profile);
555 profile = aa_get_profile(p);
556 } else {
557 __add_profile(&parent->base.profiles, profile);
558 }
559 mutex_unlock(&profile->ns->lock);
560
561 /* refcount released by caller */
562out:
563 kfree(name);
564
565 return profile;
566
567fail:
568 kfree(name);
569 aa_free_profile(profile);
570 return NULL;
571}
572
573/**
574 * replacement_allowed - test to see if replacement is allowed
575 * @profile: profile to test if it can be replaced (MAYBE NULL)
576 * @noreplace: true if replacement shouldn't be allowed but addition is okay
577 * @info: Returns - info about why replacement failed (NOT NULL)
578 *
579 * Returns: %0 if replacement allowed else error code
580 */
581static int replacement_allowed(struct aa_profile *profile, int noreplace,
582 const char **info)
583{
584 if (profile) {
585 if (profile->label.flags & FLAG_IMMUTIBLE) {
586 *info = "cannot replace immutable profile";
587 return -EPERM;
588 } else if (noreplace) {
589 *info = "profile already exists";
590 return -EEXIST;
591 }
592 }
593 return 0;
594}
595
596/* audit callback for net specific fields */
597static void audit_cb(struct audit_buffer *ab, void *va)
598{
599 struct common_audit_data *sa = va;
600
601 if (aad(sa)->iface.ns) {
602 audit_log_format(ab, " ns=");
603 audit_log_untrustedstring(ab, aad(sa)->iface.ns);
604 }
605}
606
607/**
608 * audit_policy - Do auditing of policy changes
609 * @label: label to check if it can manage policy
610 * @op: policy operation being performed
611 * @ns_name: name of namespace being manipulated
612 * @name: name of profile being manipulated (NOT NULL)
613 * @info: any extra information to be audited (MAYBE NULL)
614 * @error: error code
615 *
616 * Returns: the error to be returned after audit is done
617 */
618static int audit_policy(struct aa_label *label, const char *op,
619 const char *ns_name, const char *name,
620 const char *info, int error)
621{
622 DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, op);
623
624 aad(&sa)->iface.ns = ns_name;
625 aad(&sa)->name = name;
626 aad(&sa)->info = info;
627 aad(&sa)->error = error;
628 aad(&sa)->label = label;
629
630 aa_audit_msg(AUDIT_APPARMOR_STATUS, &sa, audit_cb);
631
632 return error;
633}
634
635/**
636 * policy_view_capable - check if viewing policy in at @ns is allowed
637 * ns: namespace being viewed by current task (may be NULL)
638 * Returns: true if viewing policy is allowed
639 *
640 * If @ns is NULL then the namespace being viewed is assumed to be the
641 * tasks current namespace.
642 */
643bool policy_view_capable(struct aa_ns *ns)
644{
645 struct user_namespace *user_ns = current_user_ns();
646 struct aa_ns *view_ns = aa_get_current_ns();
647 bool root_in_user_ns = uid_eq(current_euid(), make_kuid(user_ns, 0)) ||
648 in_egroup_p(make_kgid(user_ns, 0));
649 bool response = false;
650 if (!ns)
651 ns = view_ns;
652
653 if (root_in_user_ns && aa_ns_visible(view_ns, ns, true) &&
654 (user_ns == &init_user_ns ||
655 (unprivileged_userns_apparmor_policy != 0 &&
656 user_ns->level == view_ns->level)))
657 response = true;
658 aa_put_ns(view_ns);
659
660 return response;
661}
662
663bool policy_admin_capable(struct aa_ns *ns)
664{
665 struct user_namespace *user_ns = current_user_ns();
666 bool capable = ns_capable(user_ns, CAP_MAC_ADMIN);
667
668 AA_DEBUG("cap_mac_admin? %d\n", capable);
669 AA_DEBUG("policy locked? %d\n", aa_g_lock_policy);
670
671 return policy_view_capable(ns) && capable && !aa_g_lock_policy;
672}
673
674/**
675 * aa_may_manage_policy - can the current task manage policy
676 * @label: label to check if it can manage policy
677 * @op: the policy manipulation operation being done
678 *
679 * Returns: 0 if the task is allowed to manipulate policy else error
680 */
681int aa_may_manage_policy(struct aa_label *label, struct aa_ns *ns, u32 mask)
682{
683 const char *op;
684
685 if (mask & AA_MAY_REMOVE_POLICY)
686 op = OP_PROF_RM;
687 else if (mask & AA_MAY_REPLACE_POLICY)
688 op = OP_PROF_REPL;
689 else
690 op = OP_PROF_LOAD;
691
692 /* check if loading policy is locked out */
693 if (aa_g_lock_policy)
694 return audit_policy(label, op, NULL, NULL, "policy_locked",
695 -EACCES);
696
697 if (!policy_admin_capable(ns))
698 return audit_policy(label, op, NULL, NULL, "not policy admin",
699 -EACCES);
700
701 /* TODO: add fine grained mediation of policy loads */
702 return 0;
703}
704
705static struct aa_profile *__list_lookup_parent(struct list_head *lh,
706 struct aa_profile *profile)
707{
708 const char *base = basename(profile->base.hname);
709 long len = base - profile->base.hname;
710 struct aa_load_ent *ent;
711
712 /* parent won't have trailing // so remove from len */
713 if (len <= 2)
714 return NULL;
715 len -= 2;
716
717 list_for_each_entry(ent, lh, list) {
718 if (ent->new == profile)
719 continue;
720 if (strncmp(ent->new->base.hname, profile->base.hname, len) ==
721 0 && ent->new->base.hname[len] == 0)
722 return ent->new;
723 }
724
725 return NULL;
726}
727
728/**
729 * __replace_profile - replace @old with @new on a list
730 * @old: profile to be replaced (NOT NULL)
731 * @new: profile to replace @old with (NOT NULL)
732 * @share_proxy: transfer @old->proxy to @new
733 *
734 * Will duplicate and refcount elements that @new inherits from @old
735 * and will inherit @old children.
736 *
737 * refcount @new for list, put @old list refcount
738 *
739 * Requires: namespace list lock be held, or list not be shared
740 */
741static void __replace_profile(struct aa_profile *old, struct aa_profile *new)
742{
743 struct aa_profile *child, *tmp;
744
745 if (!list_empty(&old->base.profiles)) {
746 LIST_HEAD(lh);
747 list_splice_init_rcu(&old->base.profiles, &lh, synchronize_rcu);
748
749 list_for_each_entry_safe(child, tmp, &lh, base.list) {
750 struct aa_profile *p;
751
752 list_del_init(&child->base.list);
753 p = __find_child(&new->base.profiles, child->base.name);
754 if (p) {
755 /* @p replaces @child */
756 __replace_profile(child, p);
757 continue;
758 }
759
760 /* inherit @child and its children */
761 /* TODO: update hname of inherited children */
762 /* list refcount transferred to @new */
763 p = aa_deref_parent(child);
764 rcu_assign_pointer(child->parent, aa_get_profile(new));
765 list_add_rcu(&child->base.list, &new->base.profiles);
766 aa_put_profile(p);
767 }
768 }
769
770 if (!rcu_access_pointer(new->parent)) {
771 struct aa_profile *parent = aa_deref_parent(old);
772 rcu_assign_pointer(new->parent, aa_get_profile(parent));
773 }
774 aa_label_replace(&old->label, &new->label);
775 /* migrate dents must come after label replacement b/c update */
776 __aafs_profile_migrate_dents(old, new);
777
778 if (list_empty(&new->base.list)) {
779 /* new is not on a list already */
780 list_replace_rcu(&old->base.list, &new->base.list);
781 aa_get_profile(new);
782 aa_put_profile(old);
783 } else
784 __list_remove_profile(old);
785}
786
787/**
788 * __lookup_replace - lookup replacement information for a profile
789 * @ns - namespace the lookup occurs in
790 * @hname - name of profile to lookup
791 * @noreplace - true if not replacing an existing profile
792 * @p - Returns: profile to be replaced
793 * @info - Returns: info string on why lookup failed
794 *
795 * Returns: profile to replace (no ref) on success else ptr error
796 */
797static int __lookup_replace(struct aa_ns *ns, const char *hname,
798 bool noreplace, struct aa_profile **p,
799 const char **info)
800{
801 *p = aa_get_profile(__lookup_profile(&ns->base, hname));
802 if (*p) {
803 int error = replacement_allowed(*p, noreplace, info);
804 if (error) {
805 *info = "profile can not be replaced";
806 return error;
807 }
808 }
809
810 return 0;
811}
812
813static void share_name(struct aa_profile *old, struct aa_profile *new)
814{
815 aa_put_str(new->base.hname);
816 aa_get_str(old->base.hname);
817 new->base.hname = old->base.hname;
818 new->base.name = old->base.name;
819 new->label.hname = old->label.hname;
820}
821
822/* Update to newest version of parent after previous replacements
823 * Returns: unrefcount newest version of parent
824 */
825static struct aa_profile *update_to_newest_parent(struct aa_profile *new)
826{
827 struct aa_profile *parent, *newest;
828
829 parent = rcu_dereference_protected(new->parent,
830 mutex_is_locked(&new->ns->lock));
831 newest = aa_get_newest_profile(parent);
832
833 /* parent replaced in this atomic set? */
834 if (newest != parent) {
835 aa_put_profile(parent);
836 rcu_assign_pointer(new->parent, newest);
837 } else
838 aa_put_profile(newest);
839
840 return newest;
841}
842
843/**
844 * aa_replace_profiles - replace profile(s) on the profile list
845 * @policy_ns: namespace load is occurring on
846 * @label: label that is attempting to load/replace policy
847 * @mask: permission mask
848 * @udata: serialized data stream (NOT NULL)
849 *
850 * unpack and replace a profile on the profile list and uses of that profile
851 * by any task creds via invalidating the old version of the profile, which
852 * tasks will notice to update their own cred. If the profile does not exist
853 * on the profile list it is added.
854 *
855 * Returns: size of data consumed else error code on failure.
856 */
857ssize_t aa_replace_profiles(struct aa_ns *policy_ns, struct aa_label *label,
858 u32 mask, struct aa_loaddata *udata)
859{
860 const char *ns_name = NULL, *info = NULL;
861 struct aa_ns *ns = NULL;
862 struct aa_load_ent *ent, *tmp;
863 struct aa_loaddata *rawdata_ent;
864 const char *op;
865 ssize_t count, error;
866 LIST_HEAD(lh);
867
868 op = mask & AA_MAY_REPLACE_POLICY ? OP_PROF_REPL : OP_PROF_LOAD;
869 aa_get_loaddata(udata);
870 /* released below */
871 error = aa_unpack(udata, &lh, &ns_name);
872 if (error)
873 goto out;
874
875 /* ensure that profiles are all for the same ns
876 * TODO: update locking to remove this constaint. All profiles in
877 * the load set must succeed as a set or the load will
878 * fail. Sort ent list and take ns locks in hierarchy order
879 */
880 count = 0;
881 list_for_each_entry(ent, &lh, list) {
882 if (ns_name) {
883 if (ent->ns_name &&
884 strcmp(ent->ns_name, ns_name) != 0) {
885 info = "policy load has mixed namespaces";
886 error = -EACCES;
887 goto fail;
888 }
889 } else if (ent->ns_name) {
890 if (count) {
891 info = "policy load has mixed namespaces";
892 error = -EACCES;
893 goto fail;
894 }
895 ns_name = ent->ns_name;
896 } else
897 count++;
898 }
899 if (ns_name) {
900 ns = aa_prepare_ns(policy_ns ? policy_ns : labels_ns(label),
901 ns_name);
902 if (IS_ERR(ns)) {
903 op = OP_PROF_LOAD;
904 info = "failed to prepare namespace";
905 error = PTR_ERR(ns);
906 ns = NULL;
907 ent = NULL;
908 goto fail;
909 }
910 } else
911 ns = aa_get_ns(policy_ns ? policy_ns : labels_ns(label));
912
913 mutex_lock_nested(&ns->lock, ns->level);
914 /* check for duplicate rawdata blobs: space and file dedup */
915 list_for_each_entry(rawdata_ent, &ns->rawdata_list, list) {
916 if (aa_rawdata_eq(rawdata_ent, udata)) {
917 struct aa_loaddata *tmp;
918
919 tmp = __aa_get_loaddata(rawdata_ent);
920 /* check we didn't fail the race */
921 if (tmp) {
922 aa_put_loaddata(udata);
923 udata = tmp;
924 break;
925 }
926 }
927 }
928 /* setup parent and ns info */
929 list_for_each_entry(ent, &lh, list) {
930 struct aa_policy *policy;
931
932 ent->new->rawdata = aa_get_loaddata(udata);
933 error = __lookup_replace(ns, ent->new->base.hname,
934 !(mask & AA_MAY_REPLACE_POLICY),
935 &ent->old, &info);
936 if (error)
937 goto fail_lock;
938
939 if (ent->new->rename) {
940 error = __lookup_replace(ns, ent->new->rename,
941 !(mask & AA_MAY_REPLACE_POLICY),
942 &ent->rename, &info);
943 if (error)
944 goto fail_lock;
945 }
946
947 /* released when @new is freed */
948 ent->new->ns = aa_get_ns(ns);
949
950 if (ent->old || ent->rename)
951 continue;
952
953 /* no ref on policy only use inside lock */
954 policy = __lookup_parent(ns, ent->new->base.hname);
955 if (!policy) {
956 struct aa_profile *p;
957 p = __list_lookup_parent(&lh, ent->new);
958 if (!p) {
959 error = -ENOENT;
960 info = "parent does not exist";
961 goto fail_lock;
962 }
963 rcu_assign_pointer(ent->new->parent, aa_get_profile(p));
964 } else if (policy != &ns->base) {
965 /* released on profile replacement or free_profile */
966 struct aa_profile *p = (struct aa_profile *) policy;
967 rcu_assign_pointer(ent->new->parent, aa_get_profile(p));
968 }
969 }
970
971 /* create new fs entries for introspection if needed */
972 if (!udata->dents[AAFS_LOADDATA_DIR]) {
973 error = __aa_fs_create_rawdata(ns, udata);
974 if (error) {
975 info = "failed to create raw_data dir and files";
976 ent = NULL;
977 goto fail_lock;
978 }
979 }
980 list_for_each_entry(ent, &lh, list) {
981 if (!ent->old) {
982 struct dentry *parent;
983 if (rcu_access_pointer(ent->new->parent)) {
984 struct aa_profile *p;
985 p = aa_deref_parent(ent->new);
986 parent = prof_child_dir(p);
987 } else
988 parent = ns_subprofs_dir(ent->new->ns);
989 error = __aafs_profile_mkdir(ent->new, parent);
990 }
991
992 if (error) {
993 info = "failed to create";
994 goto fail_lock;
995 }
996 }
997
998 /* Done with checks that may fail - do actual replacement */
999 __aa_bump_ns_revision(ns);
1000 __aa_loaddata_update(udata, ns->revision);
1001 list_for_each_entry_safe(ent, tmp, &lh, list) {
1002 list_del_init(&ent->list);
1003 op = (!ent->old && !ent->rename) ? OP_PROF_LOAD : OP_PROF_REPL;
1004
1005 if (ent->old && ent->old->rawdata == ent->new->rawdata) {
1006 /* dedup actual profile replacement */
1007 audit_policy(label, op, ns_name, ent->new->base.hname,
1008 "same as current profile, skipping",
1009 error);
1010 /* break refcount cycle with proxy. */
1011 aa_put_proxy(ent->new->label.proxy);
1012 ent->new->label.proxy = NULL;
1013 goto skip;
1014 }
1015
1016 /*
1017 * TODO: finer dedup based on profile range in data. Load set
1018 * can differ but profile may remain unchanged
1019 */
1020 audit_policy(label, op, ns_name, ent->new->base.hname, NULL,
1021 error);
1022
1023 if (ent->old) {
1024 share_name(ent->old, ent->new);
1025 __replace_profile(ent->old, ent->new);
1026 } else {
1027 struct list_head *lh;
1028
1029 if (rcu_access_pointer(ent->new->parent)) {
1030 struct aa_profile *parent;
1031
1032 parent = update_to_newest_parent(ent->new);
1033 lh = &parent->base.profiles;
1034 } else
1035 lh = &ns->base.profiles;
1036 __add_profile(lh, ent->new);
1037 }
1038 skip:
1039 aa_load_ent_free(ent);
1040 }
1041 __aa_labelset_update_subtree(ns);
1042 mutex_unlock(&ns->lock);
1043
1044out:
1045 aa_put_ns(ns);
1046 aa_put_loaddata(udata);
1047 kfree(ns_name);
1048
1049 if (error)
1050 return error;
1051 return udata->size;
1052
1053fail_lock:
1054 mutex_unlock(&ns->lock);
1055
1056 /* audit cause of failure */
1057 op = (ent && !ent->old) ? OP_PROF_LOAD : OP_PROF_REPL;
1058fail:
1059 audit_policy(label, op, ns_name, ent ? ent->new->base.hname : NULL,
1060 info, error);
1061 /* audit status that rest of profiles in the atomic set failed too */
1062 info = "valid profile in failed atomic policy load";
1063 list_for_each_entry(tmp, &lh, list) {
1064 if (tmp == ent) {
1065 info = "unchecked profile in failed atomic policy load";
1066 /* skip entry that caused failure */
1067 continue;
1068 }
1069 op = (!tmp->old) ? OP_PROF_LOAD : OP_PROF_REPL;
1070 audit_policy(label, op, ns_name, tmp->new->base.hname, info,
1071 error);
1072 }
1073 list_for_each_entry_safe(ent, tmp, &lh, list) {
1074 list_del_init(&ent->list);
1075 aa_load_ent_free(ent);
1076 }
1077
1078 goto out;
1079}
1080
1081/**
1082 * aa_remove_profiles - remove profile(s) from the system
1083 * @policy_ns: namespace the remove is being done from
1084 * @subj: label attempting to remove policy
1085 * @fqname: name of the profile or namespace to remove (NOT NULL)
1086 * @size: size of the name
1087 *
1088 * Remove a profile or sub namespace from the current namespace, so that
1089 * they can not be found anymore and mark them as replaced by unconfined
1090 *
1091 * NOTE: removing confinement does not restore rlimits to preconfinement values
1092 *
1093 * Returns: size of data consume else error code if fails
1094 */
1095ssize_t aa_remove_profiles(struct aa_ns *policy_ns, struct aa_label *subj,
1096 char *fqname, size_t size)
1097{
1098 struct aa_ns *ns = NULL;
1099 struct aa_profile *profile = NULL;
1100 const char *name = fqname, *info = NULL;
1101 const char *ns_name = NULL;
1102 ssize_t error = 0;
1103
1104 if (*fqname == 0) {
1105 info = "no profile specified";
1106 error = -ENOENT;
1107 goto fail;
1108 }
1109
1110 if (fqname[0] == ':') {
1111 size_t ns_len;
1112
1113 name = aa_splitn_fqname(fqname, size, &ns_name, &ns_len);
1114 /* released below */
1115 ns = aa_lookupn_ns(policy_ns ? policy_ns : labels_ns(subj),
1116 ns_name, ns_len);
1117 if (!ns) {
1118 info = "namespace does not exist";
1119 error = -ENOENT;
1120 goto fail;
1121 }
1122 } else
1123 /* released below */
1124 ns = aa_get_ns(policy_ns ? policy_ns : labels_ns(subj));
1125
1126 if (!name) {
1127 /* remove namespace - can only happen if fqname[0] == ':' */
1128 mutex_lock_nested(&ns->parent->lock, ns->level);
1129 __aa_bump_ns_revision(ns);
1130 __aa_remove_ns(ns);
1131 mutex_unlock(&ns->parent->lock);
1132 } else {
1133 /* remove profile */
1134 mutex_lock_nested(&ns->lock, ns->level);
1135 profile = aa_get_profile(__lookup_profile(&ns->base, name));
1136 if (!profile) {
1137 error = -ENOENT;
1138 info = "profile does not exist";
1139 goto fail_ns_lock;
1140 }
1141 name = profile->base.hname;
1142 __aa_bump_ns_revision(ns);
1143 __remove_profile(profile);
1144 __aa_labelset_update_subtree(ns);
1145 mutex_unlock(&ns->lock);
1146 }
1147
1148 /* don't fail removal if audit fails */
1149 (void) audit_policy(subj, OP_PROF_RM, ns_name, name, info,
1150 error);
1151 aa_put_ns(ns);
1152 aa_put_profile(profile);
1153 return size;
1154
1155fail_ns_lock:
1156 mutex_unlock(&ns->lock);
1157 aa_put_ns(ns);
1158
1159fail:
1160 (void) audit_policy(subj, OP_PROF_RM, ns_name, name, info,
1161 error);
1162 return error;
1163}