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;
37extern int aa_unprivileged_unconfined_restricted;
38
39extern const char *const aa_profile_mode_names[];
40#define APPARMOR_MODE_NAMES_MAX_INDEX 4
41
42#define PROFILE_MODE(_profile, _mode) \
43 ((aa_g_profile_mode == (_mode)) || \
44 ((_profile)->mode == (_mode)))
45
46#define COMPLAIN_MODE(_profile) PROFILE_MODE((_profile), APPARMOR_COMPLAIN)
47
48#define USER_MODE(_profile) PROFILE_MODE((_profile), APPARMOR_USER)
49
50#define KILL_MODE(_profile) PROFILE_MODE((_profile), APPARMOR_KILL)
51
52#define PROFILE_IS_HAT(_profile) ((_profile)->label.flags & FLAG_HAT)
53
54#define CHECK_DEBUG1(_profile) ((_profile)->label.flags & FLAG_DEBUG1)
55
56#define CHECK_DEBUG2(_profile) ((_profile)->label.flags & FLAG_DEBUG2)
57
58#define profile_is_stale(_profile) (label_is_stale(&(_profile)->label))
59
60#define on_list_rcu(X) (!list_empty(X) && (X)->prev != LIST_POISON2)
61
62/*
63 * FIXME: currently need a clean way to replace and remove profiles as a
64 * set. It should be done at the namespace level.
65 * Either, with a set of profiles loaded at the namespace level or via
66 * a mark and remove marked interface.
67 */
68enum profile_mode {
69 APPARMOR_ENFORCE, /* enforce access rules */
70 APPARMOR_COMPLAIN, /* allow and log access violations */
71 APPARMOR_KILL, /* kill task on access violation */
72 APPARMOR_UNCONFINED, /* profile set to unconfined */
73 APPARMOR_USER, /* modified complain mode to userspace */
74};
75
76
77/* struct aa_policydb - match engine for a policy
78 * count: refcount for the pdb
79 * dfa: dfa pattern match
80 * perms: table of permissions
81 * strs: table of strings, index by x
82 * start: set of start states for the different classes of data
83 */
84struct aa_policydb {
85 struct kref count;
86 struct aa_dfa *dfa;
87 struct {
88 struct aa_perms *perms;
89 u32 size;
90 };
91 struct aa_str_table trans;
92 aa_state_t start[AA_CLASS_LAST + 1];
93};
94
95extern struct aa_policydb *nullpdb;
96
97struct aa_policydb *aa_alloc_pdb(gfp_t gfp);
98void aa_pdb_free_kref(struct kref *kref);
99
100/**
101 * aa_get_pdb - increment refcount on @pdb
102 * @pdb: policydb (MAYBE NULL)
103 *
104 * Returns: pointer to @pdb if @pdb is NULL will return NULL
105 * Requires: @pdb must be held with valid refcount when called
106 */
107static inline struct aa_policydb *aa_get_pdb(struct aa_policydb *pdb)
108{
109 if (pdb)
110 kref_get(kref: &(pdb->count));
111
112 return pdb;
113}
114
115/**
116 * aa_put_pdb - put a pdb refcount
117 * @pdb: pdb to put refcount (MAYBE NULL)
118 *
119 * Requires: if @pdb != NULL that a valid refcount be held
120 */
121static inline void aa_put_pdb(struct aa_policydb *pdb)
122{
123 if (pdb)
124 kref_put(kref: &pdb->count, release: aa_pdb_free_kref);
125}
126
127static inline struct aa_perms *aa_lookup_perms(struct aa_policydb *policy,
128 aa_state_t state)
129{
130 unsigned int index = ACCEPT_TABLE(policy->dfa)[state];
131
132 if (!(policy->perms))
133 return &default_perms;
134
135 return &(policy->perms[index]);
136}
137
138
139/* struct aa_data - generic data structure
140 * key: name for retrieving this data
141 * size: size of data in bytes
142 * data: binary data
143 * head: reserved for rhashtable
144 */
145struct aa_data {
146 char *key;
147 u32 size;
148 char *data;
149 struct rhash_head head;
150};
151
152/* struct aa_ruleset - data covering mediation rules
153 * @list: list the rule is on
154 * @size: the memory consumed by this ruleset
155 * @policy: general match rules governing policy
156 * @file: The set of rules governing basic file access and domain transitions
157 * @caps: capabilities for the profile
158 * @rlimits: rlimits for the profile
159 * @secmark_count: number of secmark entries
160 * @secmark: secmark label match info
161 */
162struct aa_ruleset {
163 struct list_head list;
164
165 int size;
166
167 /* TODO: merge policy and file */
168 struct aa_policydb *policy;
169 struct aa_policydb *file;
170 struct aa_caps caps;
171
172 struct aa_rlimit rlimits;
173
174 int secmark_count;
175 struct aa_secmark *secmark;
176};
177
178/* struct aa_attachment - data and rules for a profiles attachment
179 * @list:
180 * @xmatch_str: human readable attachment string
181 * @xmatch: optional extended matching for unconfined executables names
182 * @xmatch_len: xmatch prefix len, used to determine xmatch priority
183 * @xattr_count: number of xattrs in table
184 * @xattrs: table of xattrs
185 */
186struct aa_attachment {
187 const char *xmatch_str;
188 struct aa_policydb *xmatch;
189 unsigned int xmatch_len;
190 int xattr_count;
191 char **xattrs;
192};
193
194/* struct aa_profile - basic confinement data
195 * @base - base components of the profile (name, refcount, lists, lock ...)
196 * @label - label this profile is an extension of
197 * @parent: parent of profile
198 * @ns: namespace the profile is in
199 * @rename: optional profile name that this profile renamed
200 *
201 * @audit: the auditing mode of the profile
202 * @mode: the enforcement mode of the profile
203 * @path_flags: flags controlling path generation behavior
204 * @disconnected: what to prepend if attach_disconnected is specified
205 * @attach: attachment rules for the profile
206 * @rules: rules to be enforced
207 *
208 * @dents: dentries for the profiles file entries in apparmorfs
209 * @dirname: name of the profile dir in apparmorfs
210 * @data: hashtable for free-form policy aa_data
211 *
212 * The AppArmor profile contains the basic confinement data. Each profile
213 * has a name, and exists in a namespace. The @name and @exec_match are
214 * used to determine profile attachment against unconfined tasks. All other
215 * attachments are determined by profile X transition rules.
216 *
217 * Profiles have a hierarchy where hats and children profiles keep
218 * a reference to their parent.
219 *
220 * Profile names can not begin with a : and can not contain the \0
221 * character. If a profile name begins with / it will be considered when
222 * determining profile attachment on "unconfined" tasks.
223 */
224struct aa_profile {
225 struct aa_policy base;
226 struct aa_profile __rcu *parent;
227
228 struct aa_ns *ns;
229 const char *rename;
230
231 enum audit_mode audit;
232 long mode;
233 u32 path_flags;
234 const char *disconnected;
235
236 struct aa_attachment attach;
237 struct list_head rules;
238
239 struct aa_loaddata *rawdata;
240 unsigned char *hash;
241 char *dirname;
242 struct dentry *dents[AAFS_PROF_SIZEOF];
243 struct rhashtable *data;
244 struct aa_label label;
245};
246
247extern enum profile_mode aa_g_profile_mode;
248
249#define AA_MAY_LOAD_POLICY AA_MAY_APPEND
250#define AA_MAY_REPLACE_POLICY AA_MAY_WRITE
251#define AA_MAY_REMOVE_POLICY AA_MAY_DELETE
252
253#define profiles_ns(P) ((P)->ns)
254#define name_is_shared(A, B) ((A)->hname && (A)->hname == (B)->hname)
255
256struct aa_ruleset *aa_alloc_ruleset(gfp_t gfp);
257struct aa_profile *aa_alloc_profile(const char *name, struct aa_proxy *proxy,
258 gfp_t gfp);
259struct aa_profile *aa_alloc_null(struct aa_profile *parent, const char *name,
260 gfp_t gfp);
261struct aa_profile *aa_new_learning_profile(struct aa_profile *parent, bool hat,
262 const char *base, gfp_t gfp);
263void aa_free_profile(struct aa_profile *profile);
264struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name);
265struct aa_profile *aa_lookupn_profile(struct aa_ns *ns, const char *hname,
266 size_t n);
267struct aa_profile *aa_fqlookupn_profile(struct aa_label *base,
268 const char *fqname, size_t n);
269
270ssize_t aa_replace_profiles(struct aa_ns *view, struct aa_label *label,
271 u32 mask, struct aa_loaddata *udata);
272ssize_t aa_remove_profiles(struct aa_ns *view, struct aa_label *label,
273 char *name, size_t size);
274void __aa_profile_list_release(struct list_head *head);
275
276#define profile_unconfined(X) ((X)->mode == APPARMOR_UNCONFINED)
277
278/**
279 * aa_get_newest_profile - simple wrapper fn to wrap the label version
280 * @p: profile (NOT NULL)
281 *
282 * Returns refcount to newest version of the profile (maybe @p)
283 *
284 * Requires: @p must be held with a valid refcount
285 */
286static inline struct aa_profile *aa_get_newest_profile(struct aa_profile *p)
287{
288 return labels_profile(aa_get_newest_label(&p->label));
289}
290
291static inline aa_state_t RULE_MEDIATES(struct aa_ruleset *rules,
292 unsigned char class)
293{
294 if (class <= AA_CLASS_LAST)
295 return rules->policy->start[class];
296 else
297 return aa_dfa_match_len(dfa: rules->policy->dfa,
298 start: rules->policy->start[0], str: &class, len: 1);
299}
300
301static inline aa_state_t RULE_MEDIATES_AF(struct aa_ruleset *rules, u16 AF)
302{
303 aa_state_t state = RULE_MEDIATES(rules, AA_CLASS_NET);
304 __be16 be_af = cpu_to_be16(AF);
305
306 if (!state)
307 return DFA_NOMATCH;
308 return aa_dfa_match_len(dfa: rules->policy->dfa, start: state, str: (char *) &be_af, len: 2);
309}
310
311static inline aa_state_t ANY_RULE_MEDIATES(struct list_head *head,
312 unsigned char class)
313{
314 struct aa_ruleset *rule;
315
316 /* TODO: change to list walk */
317 rule = list_first_entry(head, typeof(*rule), list);
318 return RULE_MEDIATES(rules: rule, class);
319}
320
321/**
322 * aa_get_profile - increment refcount on profile @p
323 * @p: profile (MAYBE NULL)
324 *
325 * Returns: pointer to @p if @p is NULL will return NULL
326 * Requires: @p must be held with valid refcount when called
327 */
328static inline struct aa_profile *aa_get_profile(struct aa_profile *p)
329{
330 if (p)
331 kref_get(kref: &(p->label.count));
332
333 return p;
334}
335
336/**
337 * aa_get_profile_not0 - increment refcount on profile @p found via lookup
338 * @p: profile (MAYBE NULL)
339 *
340 * Returns: pointer to @p if @p is NULL will return NULL
341 * Requires: @p must be held with valid refcount when called
342 */
343static inline struct aa_profile *aa_get_profile_not0(struct aa_profile *p)
344{
345 if (p && kref_get_unless_zero(kref: &p->label.count))
346 return p;
347
348 return NULL;
349}
350
351/**
352 * aa_get_profile_rcu - increment a refcount profile that can be replaced
353 * @p: pointer to profile that can be replaced (NOT NULL)
354 *
355 * Returns: pointer to a refcounted profile.
356 * else NULL if no profile
357 */
358static inline struct aa_profile *aa_get_profile_rcu(struct aa_profile __rcu **p)
359{
360 struct aa_profile *c;
361
362 rcu_read_lock();
363 do {
364 c = rcu_dereference(*p);
365 } while (c && !kref_get_unless_zero(kref: &c->label.count));
366 rcu_read_unlock();
367
368 return c;
369}
370
371/**
372 * aa_put_profile - decrement refcount on profile @p
373 * @p: profile (MAYBE NULL)
374 */
375static inline void aa_put_profile(struct aa_profile *p)
376{
377 if (p)
378 kref_put(kref: &p->label.count, release: aa_label_kref);
379}
380
381static inline int AUDIT_MODE(struct aa_profile *profile)
382{
383 if (aa_g_audit != AUDIT_NORMAL)
384 return aa_g_audit;
385
386 return profile->audit;
387}
388
389bool aa_policy_view_capable(const struct cred *subj_cred,
390 struct aa_label *label, struct aa_ns *ns);
391bool aa_policy_admin_capable(const struct cred *subj_cred,
392 struct aa_label *label, struct aa_ns *ns);
393int aa_may_manage_policy(const struct cred *subj_cred,
394 struct aa_label *label, struct aa_ns *ns,
395 u32 mask);
396bool aa_current_policy_view_capable(struct aa_ns *ns);
397bool aa_current_policy_admin_capable(struct aa_ns *ns);
398
399#endif /* __AA_POLICY_H */
400

source code of linux/security/apparmor/include/policy.h