1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * A policy database (policydb) specifies the
4 * configuration data for the security policy.
5 *
6 * Author : Stephen Smalley, <sds@tycho.nsa.gov>
7 */
8
9 /*
10 * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
11 *
12 * Support for enhanced MLS infrastructure.
13 *
14 * Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
15 *
16 * Added conditional policy language extensions
17 *
18 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
19 * Copyright (C) 2003 - 2004 Tresys Technology, LLC
20 */
21
22 #ifndef _SS_POLICYDB_H_
23 #define _SS_POLICYDB_H_
24
25 #include "symtab.h"
26 #include "avtab.h"
27 #include "sidtab.h"
28 #include "ebitmap.h"
29 #include "mls_types.h"
30 #include "context.h"
31 #include "constraint.h"
32
33 /*
34 * A datum type is defined for each kind of symbol
35 * in the configuration data: individual permissions,
36 * common prefixes for access vectors, classes,
37 * users, roles, types, sensitivities, categories, etc.
38 */
39
40 /* Permission attributes */
41 struct perm_datum {
42 u32 value; /* permission bit + 1 */
43 };
44
45 /* Attributes of a common prefix for access vectors */
46 struct common_datum {
47 u32 value; /* internal common value */
48 struct symtab permissions; /* common permissions */
49 };
50
51 /* Class attributes */
52 struct class_datum {
53 u32 value; /* class value */
54 char *comkey; /* common name */
55 struct common_datum *comdatum; /* common datum */
56 struct symtab permissions; /* class-specific permission symbol table */
57 struct constraint_node *constraints; /* constraints on class permissions */
58 struct constraint_node *validatetrans; /* special transition rules */
59 /* Options how a new object user, role, and type should be decided */
60 #define DEFAULT_SOURCE 1
61 #define DEFAULT_TARGET 2
62 char default_user;
63 char default_role;
64 char default_type;
65 /* Options how a new object range should be decided */
66 #define DEFAULT_SOURCE_LOW 1
67 #define DEFAULT_SOURCE_HIGH 2
68 #define DEFAULT_SOURCE_LOW_HIGH 3
69 #define DEFAULT_TARGET_LOW 4
70 #define DEFAULT_TARGET_HIGH 5
71 #define DEFAULT_TARGET_LOW_HIGH 6
72 char default_range;
73 };
74
75 /* Role attributes */
76 struct role_datum {
77 u32 value; /* internal role value */
78 u32 bounds; /* boundary of role */
79 struct ebitmap dominates; /* set of roles dominated by this role */
80 struct ebitmap types; /* set of authorized types for role */
81 };
82
83 struct role_trans {
84 u32 role; /* current role */
85 u32 type; /* program executable type, or new object type */
86 u32 tclass; /* process class, or new object class */
87 u32 new_role; /* new role */
88 struct role_trans *next;
89 };
90
91 struct filename_trans {
92 u32 stype; /* current process */
93 u32 ttype; /* parent dir context */
94 u16 tclass; /* class of new object */
95 const char *name; /* last path component */
96 };
97
98 struct filename_trans_datum {
99 u32 otype; /* expected of new object */
100 };
101
102 struct role_allow {
103 u32 role; /* current role */
104 u32 new_role; /* new role */
105 struct role_allow *next;
106 };
107
108 /* Type attributes */
109 struct type_datum {
110 u32 value; /* internal type value */
111 u32 bounds; /* boundary of type */
112 unsigned char primary; /* primary name? */
113 unsigned char attribute;/* attribute ?*/
114 };
115
116 /* User attributes */
117 struct user_datum {
118 u32 value; /* internal user value */
119 u32 bounds; /* bounds of user */
120 struct ebitmap roles; /* set of authorized roles for user */
121 struct mls_range range; /* MLS range (min - max) for user */
122 struct mls_level dfltlevel; /* default login MLS level for user */
123 };
124
125
126 /* Sensitivity attributes */
127 struct level_datum {
128 struct mls_level *level; /* sensitivity and associated categories */
129 unsigned char isalias; /* is this sensitivity an alias for another? */
130 };
131
132 /* Category attributes */
133 struct cat_datum {
134 u32 value; /* internal category bit + 1 */
135 unsigned char isalias; /* is this category an alias for another? */
136 };
137
138 struct range_trans {
139 u32 source_type;
140 u32 target_type;
141 u32 target_class;
142 };
143
144 /* Boolean data type */
145 struct cond_bool_datum {
146 __u32 value; /* internal type value */
147 int state;
148 };
149
150 struct cond_node;
151
152 /*
153 * type set preserves data needed to determine constraint info from
154 * policy source. This is not used by the kernel policy but allows
155 * utilities such as audit2allow to determine constraint denials.
156 */
157 struct type_set {
158 struct ebitmap types;
159 struct ebitmap negset;
160 u32 flags;
161 };
162
163 /*
164 * The configuration data includes security contexts for
165 * initial SIDs, unlabeled file systems, TCP and UDP port numbers,
166 * network interfaces, and nodes. This structure stores the
167 * relevant data for one such entry. Entries of the same kind
168 * (e.g. all initial SIDs) are linked together into a list.
169 */
170 struct ocontext {
171 union {
172 char *name; /* name of initial SID, fs, netif, fstype, path */
173 struct {
174 u8 protocol;
175 u16 low_port;
176 u16 high_port;
177 } port; /* TCP or UDP port information */
178 struct {
179 u32 addr;
180 u32 mask;
181 } node; /* node information */
182 struct {
183 u32 addr[4];
184 u32 mask[4];
185 } node6; /* IPv6 node information */
186 struct {
187 u64 subnet_prefix;
188 u16 low_pkey;
189 u16 high_pkey;
190 } ibpkey;
191 struct {
192 char *dev_name;
193 u8 port;
194 } ibendport;
195 } u;
196 union {
197 u32 sclass; /* security class for genfs */
198 u32 behavior; /* labeling behavior for fs_use */
199 } v;
200 struct context context[2]; /* security context(s) */
201 u32 sid[2]; /* SID(s) */
202 struct ocontext *next;
203 };
204
205 struct genfs {
206 char *fstype;
207 struct ocontext *head;
208 struct genfs *next;
209 };
210
211 /* symbol table array indices */
212 #define SYM_COMMONS 0
213 #define SYM_CLASSES 1
214 #define SYM_ROLES 2
215 #define SYM_TYPES 3
216 #define SYM_USERS 4
217 #define SYM_BOOLS 5
218 #define SYM_LEVELS 6
219 #define SYM_CATS 7
220 #define SYM_NUM 8
221
222 /* object context array indices */
223 #define OCON_ISID 0 /* initial SIDs */
224 #define OCON_FS 1 /* unlabeled file systems */
225 #define OCON_PORT 2 /* TCP and UDP port numbers */
226 #define OCON_NETIF 3 /* network interfaces */
227 #define OCON_NODE 4 /* nodes */
228 #define OCON_FSUSE 5 /* fs_use */
229 #define OCON_NODE6 6 /* IPv6 nodes */
230 #define OCON_IBPKEY 7 /* Infiniband PKeys */
231 #define OCON_IBENDPORT 8 /* Infiniband end ports */
232 #define OCON_NUM 9
233
234 /* The policy database */
235 struct policydb {
236 int mls_enabled;
237 int android_netlink_route;
238
239 /* symbol tables */
240 struct symtab symtab[SYM_NUM];
241 #define p_commons symtab[SYM_COMMONS]
242 #define p_classes symtab[SYM_CLASSES]
243 #define p_roles symtab[SYM_ROLES]
244 #define p_types symtab[SYM_TYPES]
245 #define p_users symtab[SYM_USERS]
246 #define p_bools symtab[SYM_BOOLS]
247 #define p_levels symtab[SYM_LEVELS]
248 #define p_cats symtab[SYM_CATS]
249
250 /* symbol names indexed by (value - 1) */
251 char **sym_val_to_name[SYM_NUM];
252
253 /* class, role, and user attributes indexed by (value - 1) */
254 struct class_datum **class_val_to_struct;
255 struct role_datum **role_val_to_struct;
256 struct user_datum **user_val_to_struct;
257 struct type_datum **type_val_to_struct;
258
259 /* type enforcement access vectors and transitions */
260 struct avtab te_avtab;
261
262 /* role transitions */
263 struct role_trans *role_tr;
264
265 /* file transitions with the last path component */
266 /* quickly exclude lookups when parent ttype has no rules */
267 struct ebitmap filename_trans_ttypes;
268 /* actual set of filename_trans rules */
269 struct hashtab *filename_trans;
270
271 /* bools indexed by (value - 1) */
272 struct cond_bool_datum **bool_val_to_struct;
273 /* type enforcement conditional access vectors and transitions */
274 struct avtab te_cond_avtab;
275 /* linked list indexing te_cond_avtab by conditional */
276 struct cond_node *cond_list;
277
278 /* role allows */
279 struct role_allow *role_allow;
280
281 /* security contexts of initial SIDs, unlabeled file systems,
282 TCP or UDP port numbers, network interfaces and nodes */
283 struct ocontext *ocontexts[OCON_NUM];
284
285 /* security contexts for files in filesystems that cannot support
286 a persistent label mapping or use another
287 fixed labeling behavior. */
288 struct genfs *genfs;
289
290 /* range transitions table (range_trans_key -> mls_range) */
291 struct hashtab *range_tr;
292
293 /* type -> attribute reverse mapping */
294 struct ebitmap *type_attr_map_array;
295
296 struct ebitmap policycaps;
297
298 struct ebitmap permissive_map;
299
300 /* length of this policy when it was loaded */
301 size_t len;
302
303 unsigned int policyvers;
304
305 unsigned int reject_unknown : 1;
306 unsigned int allow_unknown : 1;
307
308 u16 process_class;
309 u32 process_trans_perms;
310 };
311
312 extern void policydb_destroy(struct policydb *p);
313 extern int policydb_load_isids(struct policydb *p, struct sidtab *s);
314 extern int policydb_context_isvalid(struct policydb *p, struct context *c);
315 extern int policydb_class_isvalid(struct policydb *p, unsigned int class);
316 extern int policydb_type_isvalid(struct policydb *p, unsigned int type);
317 extern int policydb_role_isvalid(struct policydb *p, unsigned int role);
318 extern int policydb_read(struct policydb *p, void *fp);
319 extern int policydb_write(struct policydb *p, void *fp);
320
321 #define PERM_SYMTAB_SIZE 32
322
323 #define POLICYDB_CONFIG_MLS 1
324 #define POLICYDB_CONFIG_ANDROID_NETLINK_ROUTE (1 << 31)
325
326 /* the config flags related to unknown classes/perms are bits 2 and 3 */
327 #define REJECT_UNKNOWN 0x00000002
328 #define ALLOW_UNKNOWN 0x00000004
329
330 #define OBJECT_R "object_r"
331 #define OBJECT_R_VAL 1
332
333 #define POLICYDB_MAGIC SELINUX_MAGIC
334 #define POLICYDB_STRING "SE Linux"
335
336 struct policy_file {
337 char *data;
338 size_t len;
339 };
340
341 struct policy_data {
342 struct policydb *p;
343 void *fp;
344 };
345
next_entry(void * buf,struct policy_file * fp,size_t bytes)346 static inline int next_entry(void *buf, struct policy_file *fp, size_t bytes)
347 {
348 if (bytes > fp->len)
349 return -EINVAL;
350
351 memcpy(buf, fp->data, bytes);
352 fp->data += bytes;
353 fp->len -= bytes;
354 return 0;
355 }
356
put_entry(const void * buf,size_t bytes,int num,struct policy_file * fp)357 static inline int put_entry(const void *buf, size_t bytes, int num, struct policy_file *fp)
358 {
359 size_t len = bytes * num;
360
361 memcpy(fp->data, buf, len);
362 fp->data += len;
363 fp->len -= len;
364
365 return 0;
366 }
367
sym_name(struct policydb * p,unsigned int sym_num,unsigned int element_nr)368 static inline char *sym_name(struct policydb *p, unsigned int sym_num, unsigned int element_nr)
369 {
370 return p->sym_val_to_name[sym_num][element_nr];
371 }
372
373 extern u16 string_to_security_class(struct policydb *p, const char *name);
374 extern u32 string_to_av_perm(struct policydb *p, u16 tclass, const char *name);
375
376 #endif /* _SS_POLICYDB_H_ */
377
378