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 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 */
61 enum 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 */
73 struct 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 */
86 struct 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 */
129 struct 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
165 extern 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
174 void aa_add_profile(struct aa_policy *common, struct aa_profile *profile);
175
176
177 void aa_free_proxy_kref(struct kref *kref);
178 struct aa_profile *aa_alloc_profile(const char *name, struct aa_proxy *proxy,
179 gfp_t gfp);
180 struct aa_profile *aa_new_null_profile(struct aa_profile *parent, bool hat,
181 const char *base, gfp_t gfp);
182 void aa_free_profile(struct aa_profile *profile);
183 void aa_free_profile_kref(struct kref *kref);
184 struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name);
185 struct aa_profile *aa_lookupn_profile(struct aa_ns *ns, const char *hname,
186 size_t n);
187 struct aa_profile *aa_lookup_profile(struct aa_ns *ns, const char *name);
188 struct aa_profile *aa_fqlookupn_profile(struct aa_label *base,
189 const char *fqname, size_t n);
190 struct aa_profile *aa_match_profile(struct aa_ns *ns, const char *name);
191
192 ssize_t aa_replace_profiles(struct aa_ns *view, struct aa_label *label,
193 u32 mask, struct aa_loaddata *udata);
194 ssize_t aa_remove_profiles(struct aa_ns *view, struct aa_label *label,
195 char *name, size_t size);
196 void __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 */
aa_get_newest_profile(struct aa_profile * p)211 static 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
PROFILE_MEDIATES(struct aa_profile * profile,unsigned char class)216 static 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
PROFILE_MEDIATES_AF(struct aa_profile * profile,u16 AF)226 static 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 */
aa_get_profile(struct aa_profile * p)243 static 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 */
aa_get_profile_not0(struct aa_profile * p)258 static 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 */
aa_get_profile_rcu(struct aa_profile __rcu ** p)273 static 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 */
aa_put_profile(struct aa_profile * p)290 static inline void aa_put_profile(struct aa_profile *p)
291 {
292 if (p)
293 kref_put(&p->label.count, aa_label_kref);
294 }
295
AUDIT_MODE(struct aa_profile * profile)296 static 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
304 bool policy_view_capable(struct aa_ns *ns);
305 bool policy_admin_capable(struct aa_ns *ns);
306 int aa_may_manage_policy(struct aa_label *label, struct aa_ns *ns,
307 u32 mask);
308
309 #endif /* __AA_POLICY_H */
310