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
34 struct aa_ns;
35
36 extern int unprivileged_userns_apparmor_policy;
37
38 extern 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 CHECK_DEBUG1(_profile) ((_profile)->label.flags & FLAG_DEBUG1)
52
53 #define CHECK_DEBUG2(_profile) ((_profile)->label.flags & FLAG_DEBUG2)
54
55 #define profile_is_stale(_profile) (label_is_stale(&(_profile)->label))
56
57 #define on_list_rcu(X) (!list_empty(X) && (X)->prev != LIST_POISON2)
58
59 /*
60 * FIXME: currently need a clean way to replace and remove profiles as a
61 * set. It should be done at the namespace level.
62 * Either, with a set of profiles loaded at the namespace level or via
63 * a mark and remove marked interface.
64 */
65 enum profile_mode {
66 APPARMOR_ENFORCE, /* enforce access rules */
67 APPARMOR_COMPLAIN, /* allow and log access violations */
68 APPARMOR_KILL, /* kill task on access violation */
69 APPARMOR_UNCONFINED, /* profile set to unconfined */
70 };
71
72
73 /* struct aa_policydb - match engine for a policy
74 * dfa: dfa pattern match
75 * start: set of start states for the different classes of data
76 */
77 struct aa_policydb {
78 /* Generic policy DFA specific rule types will be subsections of it */
79 struct aa_dfa *dfa;
80 unsigned int start[AA_CLASS_LAST + 1];
81
82 };
83
84 /* struct aa_data - generic data structure
85 * key: name for retrieving this data
86 * size: size of data in bytes
87 * data: binary data
88 * head: reserved for rhashtable
89 */
90 struct aa_data {
91 char *key;
92 u32 size;
93 char *data;
94 struct rhash_head head;
95 };
96
97
98 /* struct aa_profile - basic confinement data
99 * @base - base components of the profile (name, refcount, lists, lock ...)
100 * @label - label this profile is an extension of
101 * @parent: parent of profile
102 * @ns: namespace the profile is in
103 * @rename: optional profile name that this profile renamed
104 * @attach: human readable attachment string
105 * @xmatch: optional extended matching for unconfined executables names
106 * @xmatch_len: xmatch prefix len, used to determine xmatch priority
107 * @audit: the auditing mode of the profile
108 * @mode: the enforcement mode of the profile
109 * @path_flags: flags controlling path generation behavior
110 * @disconnected: what to prepend if attach_disconnected is specified
111 * @size: the memory consumed by this profiles rules
112 * @policy: general match rules governing policy
113 * @file: The set of rules governing basic file access and domain transitions
114 * @caps: capabilities for the profile
115 * @rlimits: rlimits for the profile
116 *
117 * @dents: dentries for the profiles file entries in apparmorfs
118 * @dirname: name of the profile dir in apparmorfs
119 * @data: hashtable for free-form policy aa_data
120 *
121 * The AppArmor profile contains the basic confinement data. Each profile
122 * has a name, and exists in a namespace. The @name and @exec_match are
123 * used to determine profile attachment against unconfined tasks. All other
124 * attachments are determined by profile X transition rules.
125 *
126 * Profiles have a hierarchy where hats and children profiles keep
127 * a reference to their parent.
128 *
129 * Profile names can not begin with a : and can not contain the \0
130 * character. If a profile name begins with / it will be considered when
131 * determining profile attachment on "unconfined" tasks.
132 */
133 struct aa_profile {
134 struct aa_policy base;
135 struct aa_profile __rcu *parent;
136
137 struct aa_ns *ns;
138 const char *rename;
139
140 const char *attach;
141 struct aa_dfa *xmatch;
142 unsigned int xmatch_len;
143 enum audit_mode audit;
144 long mode;
145 u32 path_flags;
146 const char *disconnected;
147 int size;
148
149 struct aa_policydb policy;
150 struct aa_file_rules file;
151 struct aa_caps caps;
152
153 int xattr_count;
154 char **xattrs;
155
156 struct aa_rlimit rlimits;
157
158 int secmark_count;
159 struct aa_secmark *secmark;
160
161 struct aa_loaddata *rawdata;
162 unsigned char *hash;
163 char *dirname;
164 struct dentry *dents[AAFS_PROF_SIZEOF];
165 struct rhashtable *data;
166 struct aa_label label;
167 };
168
169 extern enum profile_mode aa_g_profile_mode;
170
171 #define AA_MAY_LOAD_POLICY AA_MAY_APPEND
172 #define AA_MAY_REPLACE_POLICY AA_MAY_WRITE
173 #define AA_MAY_REMOVE_POLICY AA_MAY_DELETE
174
175 #define profiles_ns(P) ((P)->ns)
176 #define name_is_shared(A, B) ((A)->hname && (A)->hname == (B)->hname)
177
178 void aa_add_profile(struct aa_policy *common, struct aa_profile *profile);
179
180
181 void aa_free_proxy_kref(struct kref *kref);
182 struct aa_profile *aa_alloc_profile(const char *name, struct aa_proxy *proxy,
183 gfp_t gfp);
184 struct aa_profile *aa_new_null_profile(struct aa_profile *parent, bool hat,
185 const char *base, gfp_t gfp);
186 void aa_free_profile(struct aa_profile *profile);
187 void aa_free_profile_kref(struct kref *kref);
188 struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name);
189 struct aa_profile *aa_lookupn_profile(struct aa_ns *ns, const char *hname,
190 size_t n);
191 struct aa_profile *aa_lookup_profile(struct aa_ns *ns, const char *name);
192 struct aa_profile *aa_fqlookupn_profile(struct aa_label *base,
193 const char *fqname, size_t n);
194 struct aa_profile *aa_match_profile(struct aa_ns *ns, const char *name);
195
196 ssize_t aa_replace_profiles(struct aa_ns *view, struct aa_label *label,
197 u32 mask, struct aa_loaddata *udata);
198 ssize_t aa_remove_profiles(struct aa_ns *view, struct aa_label *label,
199 char *name, size_t size);
200 void __aa_profile_list_release(struct list_head *head);
201
202 #define PROF_ADD 1
203 #define PROF_REPLACE 0
204
205 #define profile_unconfined(X) ((X)->mode == APPARMOR_UNCONFINED)
206
207 /**
208 * aa_get_newest_profile - simple wrapper fn to wrap the label version
209 * @p: profile (NOT NULL)
210 *
211 * Returns refcount to newest version of the profile (maybe @p)
212 *
213 * Requires: @p must be held with a valid refcount
214 */
aa_get_newest_profile(struct aa_profile * p)215 static inline struct aa_profile *aa_get_newest_profile(struct aa_profile *p)
216 {
217 return labels_profile(aa_get_newest_label(&p->label));
218 }
219
PROFILE_MEDIATES(struct aa_profile * profile,unsigned char class)220 static inline unsigned int PROFILE_MEDIATES(struct aa_profile *profile,
221 unsigned char class)
222 {
223 if (class <= AA_CLASS_LAST)
224 return profile->policy.start[class];
225 else
226 return aa_dfa_match_len(profile->policy.dfa,
227 profile->policy.start[0], &class, 1);
228 }
229
PROFILE_MEDIATES_AF(struct aa_profile * profile,u16 AF)230 static inline unsigned int PROFILE_MEDIATES_AF(struct aa_profile *profile,
231 u16 AF) {
232 unsigned int state = PROFILE_MEDIATES(profile, AA_CLASS_NET);
233 __be16 be_af = cpu_to_be16(AF);
234
235 if (!state)
236 return 0;
237 return aa_dfa_match_len(profile->policy.dfa, state, (char *) &be_af, 2);
238 }
239
240 /**
241 * aa_get_profile - increment refcount on profile @p
242 * @p: profile (MAYBE NULL)
243 *
244 * Returns: pointer to @p if @p is NULL will return NULL
245 * Requires: @p must be held with valid refcount when called
246 */
aa_get_profile(struct aa_profile * p)247 static inline struct aa_profile *aa_get_profile(struct aa_profile *p)
248 {
249 if (p)
250 kref_get(&(p->label.count));
251
252 return p;
253 }
254
255 /**
256 * aa_get_profile_not0 - increment refcount on profile @p found via lookup
257 * @p: profile (MAYBE NULL)
258 *
259 * Returns: pointer to @p if @p is NULL will return NULL
260 * Requires: @p must be held with valid refcount when called
261 */
aa_get_profile_not0(struct aa_profile * p)262 static inline struct aa_profile *aa_get_profile_not0(struct aa_profile *p)
263 {
264 if (p && kref_get_unless_zero(&p->label.count))
265 return p;
266
267 return NULL;
268 }
269
270 /**
271 * aa_get_profile_rcu - increment a refcount profile that can be replaced
272 * @p: pointer to profile that can be replaced (NOT NULL)
273 *
274 * Returns: pointer to a refcounted profile.
275 * else NULL if no profile
276 */
aa_get_profile_rcu(struct aa_profile __rcu ** p)277 static inline struct aa_profile *aa_get_profile_rcu(struct aa_profile __rcu **p)
278 {
279 struct aa_profile *c;
280
281 rcu_read_lock();
282 do {
283 c = rcu_dereference(*p);
284 } while (c && !kref_get_unless_zero(&c->label.count));
285 rcu_read_unlock();
286
287 return c;
288 }
289
290 /**
291 * aa_put_profile - decrement refcount on profile @p
292 * @p: profile (MAYBE NULL)
293 */
aa_put_profile(struct aa_profile * p)294 static inline void aa_put_profile(struct aa_profile *p)
295 {
296 if (p)
297 kref_put(&p->label.count, aa_label_kref);
298 }
299
AUDIT_MODE(struct aa_profile * profile)300 static inline int AUDIT_MODE(struct aa_profile *profile)
301 {
302 if (aa_g_audit != AUDIT_NORMAL)
303 return aa_g_audit;
304
305 return profile->audit;
306 }
307
308 bool aa_policy_view_capable(struct aa_label *label, struct aa_ns *ns);
309 bool aa_policy_admin_capable(struct aa_label *label, struct aa_ns *ns);
310 int aa_may_manage_policy(struct aa_label *label, struct aa_ns *ns,
311 u32 mask);
312 bool aa_current_policy_view_capable(struct aa_ns *ns);
313 bool aa_current_policy_admin_capable(struct aa_ns *ns);
314
315 #endif /* __AA_POLICY_H */
316