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git.proxmox.com Git - mirror_ubuntu-zesty-kernel.git/blob - security/apparmor/policy_ns.c
2 * AppArmor security module
4 * This file contains AppArmor policy manipulation functions
6 * Copyright (C) 1998-2008 Novell/SUSE
7 * Copyright 2009-2015 Canonical Ltd.
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
14 * AppArmor policy namespaces, allow for different sets of policies
15 * to be loaded for tasks within the namespace.
18 #include <linux/list.h>
19 #include <linux/mutex.h>
20 #include <linux/slab.h>
21 #include <linux/string.h>
23 #include "include/apparmor.h"
24 #include "include/context.h"
25 #include "include/policy_ns.h"
26 #include "include/label.h"
27 #include "include/policy.h"
29 /* root profile namespace */
30 struct aa_ns
*root_ns
;
31 const char *aa_hidden_ns_name
= "---";
34 * aa_ns_visible - test if @view is visible from @curr
35 * @curr: namespace to treat as the parent (NOT NULL)
36 * @view: namespace to test if visible from @curr (NOT NULL)
37 * @subns: whether view of a subns is allowed
39 * Returns: true if @view is visible from @curr else false
41 bool aa_ns_visible(struct aa_ns
*curr
, struct aa_ns
*view
, bool subns
)
49 for ( ; view
; view
= view
->parent
) {
50 if (view
->parent
== curr
)
58 * aa_na_name - Find the ns name to display for @view from @curr
59 * @curr - current namespace (NOT NULL)
60 * @view - namespace attempting to view (NOT NULL)
61 * @subns - are subns visible
63 * Returns: name of @view visible from @curr
65 const char *aa_ns_name(struct aa_ns
*curr
, struct aa_ns
*view
, bool subns
)
67 /* if view == curr then the namespace name isn't displayed */
71 if (aa_ns_visible(curr
, view
, subns
)) {
72 /* at this point if a ns is visible it is in a view ns
73 * thus the curr ns.hname is a prefix of its name.
74 * Only output the virtualized portion of the name
75 * Add + 2 to skip over // separating curr hname prefix
76 * from the visible tail of the views hname
78 return view
->base
.hname
+ strlen(curr
->base
.hname
) + 2;
80 return aa_hidden_ns_name
;
84 * alloc_ns - allocate, initialize and return a new namespace
85 * @prefix: parent namespace name (MAYBE NULL)
86 * @name: a preallocated name (NOT NULL)
88 * Returns: refcounted namespace or NULL on failure.
90 static struct aa_ns
*alloc_ns(const char *prefix
, const char *name
)
94 ns
= kzalloc(sizeof(*ns
), GFP_KERNEL
);
95 AA_DEBUG("%s(%p)\n", __func__
, ns
);
98 if (!aa_policy_init(&ns
->base
, prefix
, name
, GFP_KERNEL
))
101 INIT_LIST_HEAD(&ns
->sub_ns
);
102 mutex_init(&ns
->lock
);
104 /* released by free_namespace */
105 ns
->unconfined
= aa_alloc_profile("unconfined", NULL
, GFP_KERNEL
);
107 goto fail_unconfined
;
109 ns
->unconfined
->label
.flags
|= FLAG_IX_ON_NAME_ERROR
|
110 FLAG_IMMUTIBLE
| FLAG_NS_COUNT
| FLAG_UNCONFINED
;
111 ns
->unconfined
->mode
= APPARMOR_UNCONFINED
;
113 /* ns and ns->unconfined share ns->unconfined refcount */
114 ns
->unconfined
->ns
= ns
;
116 atomic_set(&ns
->uniq_null
, 0);
118 aa_labelset_init(&ns
->labels
);
123 kzfree(ns
->base
.hname
);
130 * aa_free_ns - free a profile namespace
131 * @ns: the namespace to free (MAYBE NULL)
133 * Requires: All references to the namespace must have been put, if the
134 * namespace was referenced by a profile confining a task,
136 void aa_free_ns(struct aa_ns
*ns
)
141 aa_policy_destroy(&ns
->base
);
142 aa_labelset_destroy(&ns
->labels
);
143 aa_put_ns(ns
->parent
);
145 ns
->unconfined
->ns
= NULL
;
146 aa_free_profile(ns
->unconfined
);
151 * aa_find_ns - look up a profile namespace on the namespace list
152 * @root: namespace to search in (NOT NULL)
153 * @name: name of namespace to find (NOT NULL)
154 * @n: length of @name
156 * Returns: a refcounted namespace on the list, or NULL if no namespace
157 * called @name exists.
159 * refcount released by caller
161 struct aa_ns
*aa_findn_ns(struct aa_ns
*root
, const char *name
, size_t n
)
163 struct aa_ns
*ns
= NULL
;
166 ns
= aa_get_ns(__aa_findn_ns(&root
->sub_ns
, name
, n
));
173 * aa_find_ns - look up a profile namespace on the namespace list
174 * @root: namespace to search in (NOT NULL)
175 * @name: name of namespace to find (NOT NULL)
177 * Returns: a refcounted namespace on the list, or NULL if no namespace
178 * called @name exists.
180 * refcount released by caller
182 struct aa_ns
*aa_find_ns(struct aa_ns
*root
, const char *name
)
184 return aa_findn_ns(root
, name
, strlen(name
));
187 static struct aa_ns
*__aa_create_ns(struct aa_ns
*parent
, const char *name
,
195 AA_BUG(!mutex_is_locked(&parent
->lock
));
197 ns
= alloc_ns(parent
->base
.hname
, name
);
200 mutex_lock(&ns
->lock
);
201 error
= __aa_fs_ns_mkdir(ns
, ns_subns_dir(parent
), name
, dir
);
203 AA_ERROR("Failed to create interface for ns %s\n",
205 mutex_unlock(&ns
->lock
);
207 return ERR_PTR(error
);
209 ns
->parent
= aa_get_ns(parent
);
210 ns
->level
= parent
->level
+ 1;
211 list_add_rcu(&ns
->base
.list
, &parent
->sub_ns
);
215 mutex_unlock(&ns
->lock
);
221 * aa_create_ns - create an ns, fail if it already exists
222 * @parent: the parent of the namespace being created
223 * @name: the name of the namespace
224 * @dir: if not null the dir to put the ns entries in
226 * Returns: the a refcounted ns that has been add or an ERR_PTR
228 struct aa_ns
*__aa_find_or_create_ns(struct aa_ns
*parent
, const char *name
,
233 AA_BUG(!mutex_is_locked(&parent
->lock
));
235 /* try and find the specified ns */
236 /* released by caller */
237 ns
= aa_get_ns(__aa_find_ns(&parent
->sub_ns
, name
));
239 ns
= __aa_create_ns(parent
, name
, dir
);
241 ns
= ERR_PTR(-EEXIST
);
248 * aa_prepare_ns - find an existing or create a new namespace of @name
249 * @parent: ns to treat as parent
250 * @name: the namespace to find or add (NOT NULL)
252 * Returns: refcounted namespace or PTR_ERR if failed to create one
254 struct aa_ns
*aa_prepare_ns(struct aa_ns
*parent
, const char *name
)
258 mutex_lock(&parent
->lock
);
259 /* try and find the specified ns and if it doesn't exist create it */
260 /* released by caller */
261 ns
= aa_get_ns(__aa_find_ns(&parent
->sub_ns
, name
));
263 ns
= __aa_create_ns(parent
, name
, NULL
);
264 mutex_unlock(&parent
->lock
);
270 static void __ns_list_release(struct list_head
*head
);
273 * destroy_namespace - remove everything contained by @ns
274 * @ns: namespace to have it contents removed (NOT NULL)
276 static void destroy_ns(struct aa_ns
*ns
)
281 mutex_lock(&ns
->lock
);
282 /* release all profiles in this namespace */
283 __aa_profile_list_release(&ns
->base
.profiles
);
285 /* release all sub namespaces */
286 __ns_list_release(&ns
->sub_ns
);
290 write_lock_irqsave(&ns
->labels
.lock
, flags
);
291 __aa_proxy_redirect(ns_unconfined(ns
),
292 ns_unconfined(ns
->parent
));
293 write_unlock_irqrestore(&ns
->labels
.lock
, flags
);
295 __aa_fs_ns_rmdir(ns
);
296 mutex_unlock(&ns
->lock
);
300 * __aa_remove_ns - remove a namespace and all its children
301 * @ns: namespace to be removed (NOT NULL)
303 * Requires: ns->parent->lock be held and ns removed from parent.
305 void __aa_remove_ns(struct aa_ns
*ns
)
307 /* remove ns from namespace list */
308 list_del_rcu(&ns
->base
.list
);
314 * __ns_list_release - remove all profile namespaces on the list put refs
315 * @head: list of profile namespaces (NOT NULL)
317 * Requires: namespace lock be held
319 static void __ns_list_release(struct list_head
*head
)
321 struct aa_ns
*ns
, *tmp
;
322 list_for_each_entry_safe(ns
, tmp
, head
, base
.list
)
328 * aa_alloc_root_ns - allocate the root profile namespace
330 * Returns: %0 on success else error
333 int __init
aa_alloc_root_ns(void)
335 /* released by aa_free_root_ns - used as list ref*/
336 root_ns
= alloc_ns(NULL
, "root");
344 * aa_free_root_ns - free the root profile namespace
346 void __init
aa_free_root_ns(void)
348 struct aa_ns
*ns
= root_ns
;