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1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * AppArmor security module
4 *
5 * This file contains AppArmor policy definitions.
6 *
7 * Copyright (C) 1998-2008 Novell/SUSE
8 * Copyright 2009-2010 Canonical Ltd.
9 */
10
11#ifndef __AA_POLICY_H
12#define __AA_POLICY_H
13
14#include <linux/capability.h>
15#include <linux/cred.h>
16#include <linux/kref.h>
17#include <linux/rhashtable.h>
18#include <linux/sched.h>
19#include <linux/slab.h>
20#include <linux/socket.h>
21
22#include "apparmor.h"
23#include "audit.h"
24#include "capability.h"
25#include "domain.h"
26#include "file.h"
27#include "lib.h"
28#include "label.h"
29#include "net.h"
30#include "perms.h"
31#include "resource.h"
32
33
34struct aa_ns;
35
36extern int unprivileged_userns_apparmor_policy;
37
38extern const char *const aa_profile_mode_names[];
39#define APPARMOR_MODE_NAMES_MAX_INDEX 4
40
41#define PROFILE_MODE(_profile, _mode) \
42 ((aa_g_profile_mode == (_mode)) || \
43 ((_profile)->mode == (_mode)))
44
45#define COMPLAIN_MODE(_profile) PROFILE_MODE((_profile), APPARMOR_COMPLAIN)
46
47#define KILL_MODE(_profile) PROFILE_MODE((_profile), APPARMOR_KILL)
48
49#define PROFILE_IS_HAT(_profile) ((_profile)->label.flags & FLAG_HAT)
50
51#define profile_is_stale(_profile) (label_is_stale(&(_profile)->label))
52
53#define on_list_rcu(X) (!list_empty(X) && (X)->prev != LIST_POISON2)
54
55/*
56 * FIXME: currently need a clean way to replace and remove profiles as a
57 * set. It should be done at the namespace level.
58 * Either, with a set of profiles loaded at the namespace level or via
59 * a mark and remove marked interface.
60 */
61enum profile_mode {
62 APPARMOR_ENFORCE, /* enforce access rules */
63 APPARMOR_COMPLAIN, /* allow and log access violations */
64 APPARMOR_KILL, /* kill task on access violation */
65 APPARMOR_UNCONFINED, /* profile set to unconfined */
66};
67
68
69/* struct aa_policydb - match engine for a policy
70 * dfa: dfa pattern match
71 * start: set of start states for the different classes of data
72 */
73struct aa_policydb {
74 /* Generic policy DFA specific rule types will be subsections of it */
75 struct aa_dfa *dfa;
76 unsigned int start[AA_CLASS_LAST + 1];
77
78};
79
80/* struct aa_data - generic data structure
81 * key: name for retrieving this data
82 * size: size of data in bytes
83 * data: binary data
84 * head: reserved for rhashtable
85 */
86struct aa_data {
87 char *key;
88 u32 size;
89 char *data;
90 struct rhash_head head;
91};
92
93
94/* struct aa_profile - basic confinement data
95 * @base - base components of the profile (name, refcount, lists, lock ...)
96 * @label - label this profile is an extension of
97 * @parent: parent of profile
98 * @ns: namespace the profile is in
99 * @rename: optional profile name that this profile renamed
100 * @attach: human readable attachment string
101 * @xmatch: optional extended matching for unconfined executables names
102 * @xmatch_len: xmatch prefix len, used to determine xmatch priority
103 * @audit: the auditing mode of the profile
104 * @mode: the enforcement mode of the profile
105 * @path_flags: flags controlling path generation behavior
106 * @disconnected: what to prepend if attach_disconnected is specified
107 * @size: the memory consumed by this profiles rules
108 * @policy: general match rules governing policy
109 * @file: The set of rules governing basic file access and domain transitions
110 * @caps: capabilities for the profile
111 * @rlimits: rlimits for the profile
112 *
113 * @dents: dentries for the profiles file entries in apparmorfs
114 * @dirname: name of the profile dir in apparmorfs
115 * @data: hashtable for free-form policy aa_data
116 *
117 * The AppArmor profile contains the basic confinement data. Each profile
118 * has a name, and exists in a namespace. The @name and @exec_match are
119 * used to determine profile attachment against unconfined tasks. All other
120 * attachments are determined by profile X transition rules.
121 *
122 * Profiles have a hierarchy where hats and children profiles keep
123 * a reference to their parent.
124 *
125 * Profile names can not begin with a : and can not contain the \0
126 * character. If a profile name begins with / it will be considered when
127 * determining profile attachment on "unconfined" tasks.
128 */
129struct aa_profile {
130 struct aa_policy base;
131 struct aa_profile __rcu *parent;
132
133 struct aa_ns *ns;
134 const char *rename;
135
136 const char *attach;
137 struct aa_dfa *xmatch;
138 int xmatch_len;
139 enum audit_mode audit;
140 long mode;
141 u32 path_flags;
142 const char *disconnected;
143 int size;
144
145 struct aa_policydb policy;
146 struct aa_file_rules file;
147 struct aa_caps caps;
148
149 int xattr_count;
150 char **xattrs;
151
152 struct aa_rlimit rlimits;
153
154 int secmark_count;
155 struct aa_secmark *secmark;
156
157 struct aa_loaddata *rawdata;
158 unsigned char *hash;
159 char *dirname;
160 struct dentry *dents[AAFS_PROF_SIZEOF];
161 struct rhashtable *data;
162 struct aa_label label;
163};
164
165extern enum profile_mode aa_g_profile_mode;
166
167#define AA_MAY_LOAD_POLICY AA_MAY_APPEND
168#define AA_MAY_REPLACE_POLICY AA_MAY_WRITE
169#define AA_MAY_REMOVE_POLICY AA_MAY_DELETE
170
171#define profiles_ns(P) ((P)->ns)
172#define name_is_shared(A, B) ((A)->hname && (A)->hname == (B)->hname)
173
174void aa_add_profile(struct aa_policy *common, struct aa_profile *profile);
175
176
177void aa_free_proxy_kref(struct kref *kref);
178struct aa_profile *aa_alloc_profile(const char *name, struct aa_proxy *proxy,
179 gfp_t gfp);
180struct aa_profile *aa_new_null_profile(struct aa_profile *parent, bool hat,
181 const char *base, gfp_t gfp);
182void aa_free_profile(struct aa_profile *profile);
183void aa_free_profile_kref(struct kref *kref);
184struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name);
185struct aa_profile *aa_lookupn_profile(struct aa_ns *ns, const char *hname,
186 size_t n);
187struct aa_profile *aa_lookup_profile(struct aa_ns *ns, const char *name);
188struct aa_profile *aa_fqlookupn_profile(struct aa_label *base,
189 const char *fqname, size_t n);
190struct aa_profile *aa_match_profile(struct aa_ns *ns, const char *name);
191
192ssize_t aa_replace_profiles(struct aa_ns *view, struct aa_label *label,
193 u32 mask, struct aa_loaddata *udata);
194ssize_t aa_remove_profiles(struct aa_ns *view, struct aa_label *label,
195 char *name, size_t size);
196void __aa_profile_list_release(struct list_head *head);
197
198#define PROF_ADD 1
199#define PROF_REPLACE 0
200
201#define profile_unconfined(X) ((X)->mode == APPARMOR_UNCONFINED)
202
203/**
204 * aa_get_newest_profile - simple wrapper fn to wrap the label version
205 * @p: profile (NOT NULL)
206 *
207 * Returns refcount to newest version of the profile (maybe @p)
208 *
209 * Requires: @p must be held with a valid refcount
210 */
211static inline struct aa_profile *aa_get_newest_profile(struct aa_profile *p)
212{
213 return labels_profile(aa_get_newest_label(&p->label));
214}
215
216static inline unsigned int PROFILE_MEDIATES(struct aa_profile *profile,
217 unsigned char class)
218{
219 if (class <= AA_CLASS_LAST)
220 return profile->policy.start[class];
221 else
222 return aa_dfa_match_len(profile->policy.dfa,
223 profile->policy.start[0], &class, 1);
224}
225
226static inline unsigned int PROFILE_MEDIATES_AF(struct aa_profile *profile,
227 u16 AF) {
228 unsigned int state = PROFILE_MEDIATES(profile, AA_CLASS_NET);
229 __be16 be_af = cpu_to_be16(AF);
230
231 if (!state)
232 return 0;
233 return aa_dfa_match_len(profile->policy.dfa, state, (char *) &be_af, 2);
234}
235
236/**
237 * aa_get_profile - increment refcount on profile @p
238 * @p: profile (MAYBE NULL)
239 *
240 * Returns: pointer to @p if @p is NULL will return NULL
241 * Requires: @p must be held with valid refcount when called
242 */
243static inline struct aa_profile *aa_get_profile(struct aa_profile *p)
244{
245 if (p)
246 kref_get(&(p->label.count));
247
248 return p;
249}
250
251/**
252 * aa_get_profile_not0 - increment refcount on profile @p found via lookup
253 * @p: profile (MAYBE NULL)
254 *
255 * Returns: pointer to @p if @p is NULL will return NULL
256 * Requires: @p must be held with valid refcount when called
257 */
258static inline struct aa_profile *aa_get_profile_not0(struct aa_profile *p)
259{
260 if (p && kref_get_unless_zero(&p->label.count))
261 return p;
262
263 return NULL;
264}
265
266/**
267 * aa_get_profile_rcu - increment a refcount profile that can be replaced
268 * @p: pointer to profile that can be replaced (NOT NULL)
269 *
270 * Returns: pointer to a refcounted profile.
271 * else NULL if no profile
272 */
273static inline struct aa_profile *aa_get_profile_rcu(struct aa_profile __rcu **p)
274{
275 struct aa_profile *c;
276
277 rcu_read_lock();
278 do {
279 c = rcu_dereference(*p);
280 } while (c && !kref_get_unless_zero(&c->label.count));
281 rcu_read_unlock();
282
283 return c;
284}
285
286/**
287 * aa_put_profile - decrement refcount on profile @p
288 * @p: profile (MAYBE NULL)
289 */
290static inline void aa_put_profile(struct aa_profile *p)
291{
292 if (p)
293 kref_put(&p->label.count, aa_label_kref);
294}
295
296static inline int AUDIT_MODE(struct aa_profile *profile)
297{
298 if (aa_g_audit != AUDIT_NORMAL)
299 return aa_g_audit;
300
301 return profile->audit;
302}
303
304bool policy_view_capable(struct aa_ns *ns);
305bool policy_admin_capable(struct aa_ns *ns);
306int aa_may_manage_policy(struct aa_label *label, struct aa_ns *ns,
307 u32 mask);
308
309#endif /* __AA_POLICY_H */
1/*
2 * AppArmor security module
3 *
4 * This file contains AppArmor policy definitions.
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#ifndef __AA_POLICY_H
16#define __AA_POLICY_H
17
18#include <linux/capability.h>
19#include <linux/cred.h>
20#include <linux/kref.h>
21#include <linux/sched.h>
22#include <linux/slab.h>
23#include <linux/socket.h>
24
25#include "apparmor.h"
26#include "audit.h"
27#include "capability.h"
28#include "domain.h"
29#include "file.h"
30#include "resource.h"
31
32extern const char *const aa_profile_mode_names[];
33#define APPARMOR_MODE_NAMES_MAX_INDEX 4
34
35#define PROFILE_MODE(_profile, _mode) \
36 ((aa_g_profile_mode == (_mode)) || \
37 ((_profile)->mode == (_mode)))
38
39#define COMPLAIN_MODE(_profile) PROFILE_MODE((_profile), APPARMOR_COMPLAIN)
40
41#define KILL_MODE(_profile) PROFILE_MODE((_profile), APPARMOR_KILL)
42
43#define PROFILE_IS_HAT(_profile) ((_profile)->flags & PFLAG_HAT)
44
45#define PROFILE_INVALID(_profile) ((_profile)->flags & PFLAG_INVALID)
46
47#define on_list_rcu(X) (!list_empty(X) && (X)->prev != LIST_POISON2)
48
49/*
50 * FIXME: currently need a clean way to replace and remove profiles as a
51 * set. It should be done at the namespace level.
52 * Either, with a set of profiles loaded at the namespace level or via
53 * a mark and remove marked interface.
54 */
55enum profile_mode {
56 APPARMOR_ENFORCE, /* enforce access rules */
57 APPARMOR_COMPLAIN, /* allow and log access violations */
58 APPARMOR_KILL, /* kill task on access violation */
59 APPARMOR_UNCONFINED, /* profile set to unconfined */
60};
61
62enum profile_flags {
63 PFLAG_HAT = 1, /* profile is a hat */
64 PFLAG_NULL = 4, /* profile is null learning profile */
65 PFLAG_IX_ON_NAME_ERROR = 8, /* fallback to ix on name lookup fail */
66 PFLAG_IMMUTABLE = 0x10, /* don't allow changes/replacement */
67 PFLAG_USER_DEFINED = 0x20, /* user based profile - lower privs */
68 PFLAG_NO_LIST_REF = 0x40, /* list doesn't keep profile ref */
69 PFLAG_OLD_NULL_TRANS = 0x100, /* use // as the null transition */
70 PFLAG_INVALID = 0x200, /* profile replaced/removed */
71 PFLAG_NS_COUNT = 0x400, /* carries NS ref count */
72
73 /* These flags must correspond with PATH_flags */
74 PFLAG_MEDIATE_DELETED = 0x10000, /* mediate instead delegate deleted */
75};
76
77struct aa_profile;
78
79/* struct aa_policy - common part of both namespaces and profiles
80 * @name: name of the object
81 * @hname - The hierarchical name
82 * @list: list policy object is on
83 * @profiles: head of the profiles list contained in the object
84 */
85struct aa_policy {
86 char *name;
87 char *hname;
88 struct list_head list;
89 struct list_head profiles;
90};
91
92/* struct aa_ns_acct - accounting of profiles in namespace
93 * @max_size: maximum space allowed for all profiles in namespace
94 * @max_count: maximum number of profiles that can be in this namespace
95 * @size: current size of profiles
96 * @count: current count of profiles (includes null profiles)
97 */
98struct aa_ns_acct {
99 int max_size;
100 int max_count;
101 int size;
102 int count;
103};
104
105/* struct aa_namespace - namespace for a set of profiles
106 * @base: common policy
107 * @parent: parent of namespace
108 * @lock: lock for modifying the object
109 * @acct: accounting for the namespace
110 * @unconfined: special unconfined profile for the namespace
111 * @sub_ns: list of namespaces under the current namespace.
112 * @uniq_null: uniq value used for null learning profiles
113 * @uniq_id: a unique id count for the profiles in the namespace
114 * @dents: dentries for the namespaces file entries in apparmorfs
115 *
116 * An aa_namespace defines the set profiles that are searched to determine
117 * which profile to attach to a task. Profiles can not be shared between
118 * aa_namespaces and profile names within a namespace are guaranteed to be
119 * unique. When profiles in separate namespaces have the same name they
120 * are NOT considered to be equivalent.
121 *
122 * Namespaces are hierarchical and only namespaces and profiles below the
123 * current namespace are visible.
124 *
125 * Namespace names must be unique and can not contain the characters :/\0
126 *
127 * FIXME TODO: add vserver support of namespaces (can it all be done in
128 * userspace?)
129 */
130struct aa_namespace {
131 struct aa_policy base;
132 struct aa_namespace *parent;
133 struct mutex lock;
134 struct aa_ns_acct acct;
135 struct aa_profile *unconfined;
136 struct list_head sub_ns;
137 atomic_t uniq_null;
138 long uniq_id;
139
140 struct dentry *dents[AAFS_NS_SIZEOF];
141};
142
143/* struct aa_policydb - match engine for a policy
144 * dfa: dfa pattern match
145 * start: set of start states for the different classes of data
146 */
147struct aa_policydb {
148 /* Generic policy DFA specific rule types will be subsections of it */
149 struct aa_dfa *dfa;
150 unsigned int start[AA_CLASS_LAST + 1];
151
152};
153
154struct aa_replacedby {
155 struct kref count;
156 struct aa_profile __rcu *profile;
157};
158
159
160/* struct aa_profile - basic confinement data
161 * @base - base components of the profile (name, refcount, lists, lock ...)
162 * @count: reference count of the obj
163 * @rcu: rcu head used when removing from @list
164 * @parent: parent of profile
165 * @ns: namespace the profile is in
166 * @replacedby: is set to the profile that replaced this profile
167 * @rename: optional profile name that this profile renamed
168 * @attach: human readable attachment string
169 * @xmatch: optional extended matching for unconfined executables names
170 * @xmatch_len: xmatch prefix len, used to determine xmatch priority
171 * @audit: the auditing mode of the profile
172 * @mode: the enforcement mode of the profile
173 * @flags: flags controlling profile behavior
174 * @path_flags: flags controlling path generation behavior
175 * @size: the memory consumed by this profiles rules
176 * @policy: general match rules governing policy
177 * @file: The set of rules governing basic file access and domain transitions
178 * @caps: capabilities for the profile
179 * @rlimits: rlimits for the profile
180 *
181 * @dents: dentries for the profiles file entries in apparmorfs
182 * @dirname: name of the profile dir in apparmorfs
183 *
184 * The AppArmor profile contains the basic confinement data. Each profile
185 * has a name, and exists in a namespace. The @name and @exec_match are
186 * used to determine profile attachment against unconfined tasks. All other
187 * attachments are determined by profile X transition rules.
188 *
189 * The @replacedby struct is write protected by the profile lock.
190 *
191 * Profiles have a hierarchy where hats and children profiles keep
192 * a reference to their parent.
193 *
194 * Profile names can not begin with a : and can not contain the \0
195 * character. If a profile name begins with / it will be considered when
196 * determining profile attachment on "unconfined" tasks.
197 */
198struct aa_profile {
199 struct aa_policy base;
200 struct kref count;
201 struct rcu_head rcu;
202 struct aa_profile __rcu *parent;
203
204 struct aa_namespace *ns;
205 struct aa_replacedby *replacedby;
206 const char *rename;
207
208 const char *attach;
209 struct aa_dfa *xmatch;
210 int xmatch_len;
211 enum audit_mode audit;
212 long mode;
213 long flags;
214 u32 path_flags;
215 int size;
216
217 struct aa_policydb policy;
218 struct aa_file_rules file;
219 struct aa_caps caps;
220 struct aa_rlimit rlimits;
221
222 unsigned char *hash;
223 char *dirname;
224 struct dentry *dents[AAFS_PROF_SIZEOF];
225};
226
227extern struct aa_namespace *root_ns;
228extern enum profile_mode aa_g_profile_mode;
229
230void aa_add_profile(struct aa_policy *common, struct aa_profile *profile);
231
232bool aa_ns_visible(struct aa_namespace *curr, struct aa_namespace *view);
233const char *aa_ns_name(struct aa_namespace *parent, struct aa_namespace *child);
234int aa_alloc_root_ns(void);
235void aa_free_root_ns(void);
236void aa_free_namespace_kref(struct kref *kref);
237
238struct aa_namespace *aa_find_namespace(struct aa_namespace *root,
239 const char *name);
240
241
242void aa_free_replacedby_kref(struct kref *kref);
243struct aa_profile *aa_alloc_profile(const char *name);
244struct aa_profile *aa_new_null_profile(struct aa_profile *parent, int hat);
245void aa_free_profile(struct aa_profile *profile);
246void aa_free_profile_kref(struct kref *kref);
247struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name);
248struct aa_profile *aa_lookup_profile(struct aa_namespace *ns, const char *name);
249struct aa_profile *aa_match_profile(struct aa_namespace *ns, const char *name);
250
251ssize_t aa_replace_profiles(void *udata, size_t size, bool noreplace);
252ssize_t aa_remove_profiles(char *name, size_t size);
253
254#define PROF_ADD 1
255#define PROF_REPLACE 0
256
257#define unconfined(X) ((X)->mode == APPARMOR_UNCONFINED)
258
259
260static inline struct aa_profile *aa_deref_parent(struct aa_profile *p)
261{
262 return rcu_dereference_protected(p->parent,
263 mutex_is_locked(&p->ns->lock));
264}
265
266/**
267 * aa_get_profile - increment refcount on profile @p
268 * @p: profile (MAYBE NULL)
269 *
270 * Returns: pointer to @p if @p is NULL will return NULL
271 * Requires: @p must be held with valid refcount when called
272 */
273static inline struct aa_profile *aa_get_profile(struct aa_profile *p)
274{
275 if (p)
276 kref_get(&(p->count));
277
278 return p;
279}
280
281/**
282 * aa_get_profile_not0 - increment refcount on profile @p found via lookup
283 * @p: profile (MAYBE NULL)
284 *
285 * Returns: pointer to @p if @p is NULL will return NULL
286 * Requires: @p must be held with valid refcount when called
287 */
288static inline struct aa_profile *aa_get_profile_not0(struct aa_profile *p)
289{
290 if (p && kref_get_not0(&p->count))
291 return p;
292
293 return NULL;
294}
295
296/**
297 * aa_get_profile_rcu - increment a refcount profile that can be replaced
298 * @p: pointer to profile that can be replaced (NOT NULL)
299 *
300 * Returns: pointer to a refcounted profile.
301 * else NULL if no profile
302 */
303static inline struct aa_profile *aa_get_profile_rcu(struct aa_profile __rcu **p)
304{
305 struct aa_profile *c;
306
307 rcu_read_lock();
308 do {
309 c = rcu_dereference(*p);
310 } while (c && !kref_get_not0(&c->count));
311 rcu_read_unlock();
312
313 return c;
314}
315
316/**
317 * aa_get_newest_profile - find the newest version of @profile
318 * @profile: the profile to check for newer versions of
319 *
320 * Returns: refcounted newest version of @profile taking into account
321 * replacement, renames and removals
322 * return @profile.
323 */
324static inline struct aa_profile *aa_get_newest_profile(struct aa_profile *p)
325{
326 if (!p)
327 return NULL;
328
329 if (PROFILE_INVALID(p))
330 return aa_get_profile_rcu(&p->replacedby->profile);
331
332 return aa_get_profile(p);
333}
334
335/**
336 * aa_put_profile - decrement refcount on profile @p
337 * @p: profile (MAYBE NULL)
338 */
339static inline void aa_put_profile(struct aa_profile *p)
340{
341 if (p)
342 kref_put(&p->count, aa_free_profile_kref);
343}
344
345static inline struct aa_replacedby *aa_get_replacedby(struct aa_replacedby *p)
346{
347 if (p)
348 kref_get(&(p->count));
349
350 return p;
351}
352
353static inline void aa_put_replacedby(struct aa_replacedby *p)
354{
355 if (p)
356 kref_put(&p->count, aa_free_replacedby_kref);
357}
358
359/* requires profile list write lock held */
360static inline void __aa_update_replacedby(struct aa_profile *orig,
361 struct aa_profile *new)
362{
363 struct aa_profile *tmp;
364 tmp = rcu_dereference_protected(orig->replacedby->profile,
365 mutex_is_locked(&orig->ns->lock));
366 rcu_assign_pointer(orig->replacedby->profile, aa_get_profile(new));
367 orig->flags |= PFLAG_INVALID;
368 aa_put_profile(tmp);
369}
370
371/**
372 * aa_get_namespace - increment references count on @ns
373 * @ns: namespace to increment reference count of (MAYBE NULL)
374 *
375 * Returns: pointer to @ns, if @ns is NULL returns NULL
376 * Requires: @ns must be held with valid refcount when called
377 */
378static inline struct aa_namespace *aa_get_namespace(struct aa_namespace *ns)
379{
380 if (ns)
381 aa_get_profile(ns->unconfined);
382
383 return ns;
384}
385
386/**
387 * aa_put_namespace - decrement refcount on @ns
388 * @ns: namespace to put reference of
389 *
390 * Decrement reference count of @ns and if no longer in use free it
391 */
392static inline void aa_put_namespace(struct aa_namespace *ns)
393{
394 if (ns)
395 aa_put_profile(ns->unconfined);
396}
397
398static inline int AUDIT_MODE(struct aa_profile *profile)
399{
400 if (aa_g_audit != AUDIT_NORMAL)
401 return aa_g_audit;
402
403 return profile->audit;
404}
405
406bool aa_may_manage_policy(int op);
407
408#endif /* __AA_POLICY_H */