1 /*
2 * A policy database (policydb) specifies the
3 * configuration data for the security policy.
4 *
5 * Author : Stephen Smalley, <sds@tycho.nsa.gov>
6 */
7
8 /*
9 * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
10 *
11 * Support for enhanced MLS infrastructure.
12 *
13 * Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
14 *
15 * Added conditional policy language extensions
16 *
17 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
18 * Copyright (C) 2003 - 2004 Tresys Technology, LLC
19 * This program is free software; you can redistribute it and/or modify
20 * it under the terms of the GNU General Public License as published by
21 * the Free Software Foundation, version 2.
22 */
23
24 #ifndef _SS_POLICYDB_H_
25 #define _SS_POLICYDB_H_
26
27 #include <linux/flex_array.h>
28
29 #include "symtab.h"
30 #include "avtab.h"
31 #include "sidtab.h"
32 #include "ebitmap.h"
33 #include "mls_types.h"
34 #include "context.h"
35 #include "constraint.h"
36
37 /*
38 * A datum type is defined for each kind of symbol
39 * in the configuration data: individual permissions,
40 * common prefixes for access vectors, classes,
41 * users, roles, types, sensitivities, categories, etc.
42 */
43
44 /* Permission attributes */
45 struct perm_datum {
46 u32 value; /* permission bit + 1 */
47 };
48
49 /* Attributes of a common prefix for access vectors */
50 struct common_datum {
51 u32 value; /* internal common value */
52 struct symtab permissions; /* common permissions */
53 };
54
55 /* Class attributes */
56 struct class_datum {
57 u32 value; /* class value */
58 char *comkey; /* common name */
59 struct common_datum *comdatum; /* common datum */
60 struct symtab permissions; /* class-specific permission symbol table */
61 struct constraint_node *constraints; /* constraints on class permissions */
62 struct constraint_node *validatetrans; /* special transition rules */
63 /* Options how a new object user, role, and type should be decided */
64 #define DEFAULT_SOURCE 1
65 #define DEFAULT_TARGET 2
66 char default_user;
67 char default_role;
68 char default_type;
69 /* Options how a new object range should be decided */
70 #define DEFAULT_SOURCE_LOW 1
71 #define DEFAULT_SOURCE_HIGH 2
72 #define DEFAULT_SOURCE_LOW_HIGH 3
73 #define DEFAULT_TARGET_LOW 4
74 #define DEFAULT_TARGET_HIGH 5
75 #define DEFAULT_TARGET_LOW_HIGH 6
76 char default_range;
77 };
78
79 /* Role attributes */
80 struct role_datum {
81 u32 value; /* internal role value */
82 u32 bounds; /* boundary of role */
83 struct ebitmap dominates; /* set of roles dominated by this role */
84 struct ebitmap types; /* set of authorized types for role */
85 };
86
87 struct role_trans {
88 u32 role; /* current role */
89 u32 type; /* program executable type, or new object type */
90 u32 tclass; /* process class, or new object class */
91 u32 new_role; /* new role */
92 struct role_trans *next;
93 };
94
95 struct filename_trans {
96 u32 stype; /* current process */
97 u32 ttype; /* parent dir context */
98 u16 tclass; /* class of new object */
99 const char *name; /* last path component */
100 };
101
102 struct filename_trans_datum {
103 u32 otype; /* expected of new object */
104 };
105
106 struct role_allow {
107 u32 role; /* current role */
108 u32 new_role; /* new role */
109 struct role_allow *next;
110 };
111
112 /* Type attributes */
113 struct type_datum {
114 u32 value; /* internal type value */
115 u32 bounds; /* boundary of type */
116 unsigned char primary; /* primary name? */
117 unsigned char attribute;/* attribute ?*/
118 };
119
120 /* User attributes */
121 struct user_datum {
122 u32 value; /* internal user value */
123 u32 bounds; /* bounds of user */
124 struct ebitmap roles; /* set of authorized roles for user */
125 struct mls_range range; /* MLS range (min - max) for user */
126 struct mls_level dfltlevel; /* default login MLS level for user */
127 };
128
129
130 /* Sensitivity attributes */
131 struct level_datum {
132 struct mls_level *level; /* sensitivity and associated categories */
133 unsigned char isalias; /* is this sensitivity an alias for another? */
134 };
135
136 /* Category attributes */
137 struct cat_datum {
138 u32 value; /* internal category bit + 1 */
139 unsigned char isalias; /* is this category an alias for another? */
140 };
141
142 struct range_trans {
143 u32 source_type;
144 u32 target_type;
145 u32 target_class;
146 };
147
148 /* Boolean data type */
149 struct cond_bool_datum {
150 __u32 value; /* internal type value */
151 int state;
152 };
153
154 struct cond_node;
155
156 /*
157 * type set preserves data needed to determine constraint info from
158 * policy source. This is not used by the kernel policy but allows
159 * utilities such as audit2allow to determine constraint denials.
160 */
161 struct type_set {
162 struct ebitmap types;
163 struct ebitmap negset;
164 u32 flags;
165 };
166
167 /*
168 * The configuration data includes security contexts for
169 * initial SIDs, unlabeled file systems, TCP and UDP port numbers,
170 * network interfaces, and nodes. This structure stores the
171 * relevant data for one such entry. Entries of the same kind
172 * (e.g. all initial SIDs) are linked together into a list.
173 */
174 struct ocontext {
175 union {
176 char *name; /* name of initial SID, fs, netif, fstype, path */
177 struct {
178 u8 protocol;
179 u16 low_port;
180 u16 high_port;
181 } port; /* TCP or UDP port information */
182 struct {
183 u32 addr;
184 u32 mask;
185 } node; /* node information */
186 struct {
187 u32 addr[4];
188 u32 mask[4];
189 } node6; /* IPv6 node information */
190 struct {
191 u64 subnet_prefix;
192 u16 low_pkey;
193 u16 high_pkey;
194 } ibpkey;
195 struct {
196 char *dev_name;
197 u8 port;
198 } ibendport;
199 } u;
200 union {
201 u32 sclass; /* security class for genfs */
202 u32 behavior; /* labeling behavior for fs_use */
203 } v;
204 struct context context[2]; /* security context(s) */
205 u32 sid[2]; /* SID(s) */
206 struct ocontext *next;
207 };
208
209 struct genfs {
210 char *fstype;
211 struct ocontext *head;
212 struct genfs *next;
213 };
214
215 /* symbol table array indices */
216 #define SYM_COMMONS 0
217 #define SYM_CLASSES 1
218 #define SYM_ROLES 2
219 #define SYM_TYPES 3
220 #define SYM_USERS 4
221 #define SYM_BOOLS 5
222 #define SYM_LEVELS 6
223 #define SYM_CATS 7
224 #define SYM_NUM 8
225
226 /* object context array indices */
227 #define OCON_ISID 0 /* initial SIDs */
228 #define OCON_FS 1 /* unlabeled file systems */
229 #define OCON_PORT 2 /* TCP and UDP port numbers */
230 #define OCON_NETIF 3 /* network interfaces */
231 #define OCON_NODE 4 /* nodes */
232 #define OCON_FSUSE 5 /* fs_use */
233 #define OCON_NODE6 6 /* IPv6 nodes */
234 #define OCON_IBPKEY 7 /* Infiniband PKeys */
235 #define OCON_IBENDPORT 8 /* Infiniband end ports */
236 #define OCON_NUM 9
237
238 /* The policy database */
239 struct policydb {
240 int mls_enabled;
241 int android_netlink_route;
242
243 /* symbol tables */
244 struct symtab symtab[SYM_NUM];
245 #define p_commons symtab[SYM_COMMONS]
246 #define p_classes symtab[SYM_CLASSES]
247 #define p_roles symtab[SYM_ROLES]
248 #define p_types symtab[SYM_TYPES]
249 #define p_users symtab[SYM_USERS]
250 #define p_bools symtab[SYM_BOOLS]
251 #define p_levels symtab[SYM_LEVELS]
252 #define p_cats symtab[SYM_CATS]
253
254 /* symbol names indexed by (value - 1) */
255 struct flex_array *sym_val_to_name[SYM_NUM];
256
257 /* class, role, and user attributes indexed by (value - 1) */
258 struct class_datum **class_val_to_struct;
259 struct role_datum **role_val_to_struct;
260 struct user_datum **user_val_to_struct;
261 struct flex_array *type_val_to_struct_array;
262
263 /* type enforcement access vectors and transitions */
264 struct avtab te_avtab;
265
266 /* role transitions */
267 struct role_trans *role_tr;
268
269 /* file transitions with the last path component */
270 /* quickly exclude lookups when parent ttype has no rules */
271 struct ebitmap filename_trans_ttypes;
272 /* actual set of filename_trans rules */
273 struct hashtab *filename_trans;
274
275 /* bools indexed by (value - 1) */
276 struct cond_bool_datum **bool_val_to_struct;
277 /* type enforcement conditional access vectors and transitions */
278 struct avtab te_cond_avtab;
279 /* linked list indexing te_cond_avtab by conditional */
280 struct cond_node *cond_list;
281
282 /* role allows */
283 struct role_allow *role_allow;
284
285 /* security contexts of initial SIDs, unlabeled file systems,
286 TCP or UDP port numbers, network interfaces and nodes */
287 struct ocontext *ocontexts[OCON_NUM];
288
289 /* security contexts for files in filesystems that cannot support
290 a persistent label mapping or use another
291 fixed labeling behavior. */
292 struct genfs *genfs;
293
294 /* range transitions table (range_trans_key -> mls_range) */
295 struct hashtab *range_tr;
296
297 /* type -> attribute reverse mapping */
298 struct flex_array *type_attr_map_array;
299
300 struct ebitmap policycaps;
301
302 struct ebitmap permissive_map;
303
304 /* length of this policy when it was loaded */
305 size_t len;
306
307 unsigned int policyvers;
308
309 unsigned int reject_unknown : 1;
310 unsigned int allow_unknown : 1;
311
312 u16 process_class;
313 u32 process_trans_perms;
314 };
315
316 extern void policydb_destroy(struct policydb *p);
317 extern int policydb_load_isids(struct policydb *p, struct sidtab *s);
318 extern int policydb_context_isvalid(struct policydb *p, struct context *c);
319 extern int policydb_class_isvalid(struct policydb *p, unsigned int class);
320 extern int policydb_type_isvalid(struct policydb *p, unsigned int type);
321 extern int policydb_role_isvalid(struct policydb *p, unsigned int role);
322 extern int policydb_read(struct policydb *p, void *fp);
323 extern int policydb_write(struct policydb *p, void *fp);
324
325 #define PERM_SYMTAB_SIZE 32
326
327 #define POLICYDB_CONFIG_MLS 1
328 #define POLICYDB_CONFIG_ANDROID_NETLINK_ROUTE (1 << 31)
329
330 /* the config flags related to unknown classes/perms are bits 2 and 3 */
331 #define REJECT_UNKNOWN 0x00000002
332 #define ALLOW_UNKNOWN 0x00000004
333
334 #define OBJECT_R "object_r"
335 #define OBJECT_R_VAL 1
336
337 #define POLICYDB_MAGIC SELINUX_MAGIC
338 #define POLICYDB_STRING "SE Linux"
339
340 struct policy_file {
341 char *data;
342 size_t len;
343 };
344
345 struct policy_data {
346 struct policydb *p;
347 void *fp;
348 };
349
next_entry(void * buf,struct policy_file * fp,size_t bytes)350 static inline int next_entry(void *buf, struct policy_file *fp, size_t bytes)
351 {
352 if (bytes > fp->len)
353 return -EINVAL;
354
355 memcpy(buf, fp->data, bytes);
356 fp->data += bytes;
357 fp->len -= bytes;
358 return 0;
359 }
360
put_entry(const void * buf,size_t bytes,int num,struct policy_file * fp)361 static inline int put_entry(const void *buf, size_t bytes, int num, struct policy_file *fp)
362 {
363 size_t len = bytes * num;
364
365 memcpy(fp->data, buf, len);
366 fp->data += len;
367 fp->len -= len;
368
369 return 0;
370 }
371
sym_name(struct policydb * p,unsigned int sym_num,unsigned int element_nr)372 static inline char *sym_name(struct policydb *p, unsigned int sym_num, unsigned int element_nr)
373 {
374 struct flex_array *fa = p->sym_val_to_name[sym_num];
375
376 return flex_array_get_ptr(fa, element_nr);
377 }
378
379 extern u16 string_to_security_class(struct policydb *p, const char *name);
380 extern u32 string_to_av_perm(struct policydb *p, u16 tclass, const char *name);
381
382 #endif /* _SS_POLICYDB_H_ */
383
384