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