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, <stephen.smalley.work@gmail.com>
7 */
8
9 /*
10 * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
11 * Support for enhanced MLS infrastructure.
12 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
13 *
14 * Updated: Frank Mayer <mayerf@tresys.com> and
15 * Karl MacMillan <kmacmillan@tresys.com>
16 * Added conditional policy language extensions
17 * Copyright (C) 2003-2004 Tresys Technology, LLC
18 */
19
20 #ifndef _SS_POLICYDB_H_
21 #define _SS_POLICYDB_H_
22
23 #include "symtab.h"
24 #include "avtab.h"
25 #include "sidtab.h"
26 #include "ebitmap.h"
27 #include "mls_types.h"
28 #include "context.h"
29 #include "constraint.h"
30
31 /*
32 * A datum type is defined for each kind of symbol
33 * in the configuration data: individual permissions,
34 * common prefixes for access vectors, classes,
35 * users, roles, types, sensitivities, categories, etc.
36 */
37
38 /* Permission attributes */
39 struct perm_datum {
40 u32 value; /* permission bit + 1 */
41 };
42
43 /* Attributes of a common prefix for access vectors */
44 struct common_datum {
45 u32 value; /* internal common value */
46 struct symtab permissions; /* common permissions */
47 };
48
49 /* Class attributes */
50 struct class_datum {
51 u32 value; /* class value */
52 char *comkey; /* common name */
53 struct common_datum *comdatum; /* common datum */
54 struct symtab permissions; /* class-specific permission symbol table */
55 struct constraint_node *constraints; /* constraints on class perms */
56 struct constraint_node *validatetrans; /* special transition rules */
57 /* Options how a new object user, role, and type should be decided */
58 #define DEFAULT_SOURCE 1
59 #define DEFAULT_TARGET 2
60 char default_user;
61 char default_role;
62 char default_type;
63 /* Options how a new object range should be decided */
64 #define DEFAULT_SOURCE_LOW 1
65 #define DEFAULT_SOURCE_HIGH 2
66 #define DEFAULT_SOURCE_LOW_HIGH 3
67 #define DEFAULT_TARGET_LOW 4
68 #define DEFAULT_TARGET_HIGH 5
69 #define DEFAULT_TARGET_LOW_HIGH 6
70 #define DEFAULT_GLBLUB 7
71 char default_range;
72 };
73
74 /* Role attributes */
75 struct role_datum {
76 u32 value; /* internal role value */
77 u32 bounds; /* boundary of role */
78 struct ebitmap dominates; /* set of roles dominated by this role */
79 struct ebitmap types; /* set of authorized types for role */
80 };
81
82 struct role_trans_key {
83 u32 role; /* current role */
84 u32 type; /* program executable type, or new object type */
85 u32 tclass; /* process class, or new object class */
86 };
87
88 struct role_trans_datum {
89 u32 new_role; /* new role */
90 };
91
92 struct filename_trans_key {
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 struct ebitmap stypes; /* bitmap of source types for this otype */
100 u32 otype; /* resulting type of new object */
101 struct filename_trans_datum *next; /* record for next otype*/
102 };
103
104 struct role_allow {
105 u32 role; /* current role */
106 u32 new_role; /* new role */
107 struct role_allow *next;
108 };
109
110 /* Type attributes */
111 struct type_datum {
112 u32 value; /* internal type value */
113 u32 bounds; /* boundary of type */
114 unsigned char primary; /* primary name? */
115 unsigned char attribute; /* attribute ?*/
116 };
117
118 /* User attributes */
119 struct user_datum {
120 u32 value; /* internal user value */
121 u32 bounds; /* bounds of user */
122 struct ebitmap roles; /* set of authorized roles for user */
123 struct mls_range range; /* MLS range (min - max) for user */
124 struct mls_level dfltlevel; /* default login MLS level for user */
125 };
126
127 /* Sensitivity attributes */
128 struct level_datum {
129 struct mls_level level; /* sensitivity and associated categories */
130 unsigned char isalias; /* is this sensitivity an alias for another? */
131 };
132
133 /* Category attributes */
134 struct cat_datum {
135 u32 value; /* internal category bit + 1 */
136 unsigned char isalias; /* is this category an alias for another? */
137 };
138
139 struct range_trans {
140 u32 source_type;
141 u32 target_type;
142 u32 target_class;
143 };
144
145 /* Boolean data type */
146 struct cond_bool_datum {
147 u32 value; /* internal type value */
148 int state;
149 };
150
151 struct cond_node;
152
153 /*
154 * type set preserves data needed to determine constraint info from
155 * policy source. This is not used by the kernel policy but allows
156 * utilities such as audit2allow to determine constraint denials.
157 */
158 struct type_set {
159 struct ebitmap types;
160 struct ebitmap negset;
161 u32 flags;
162 };
163
164 /*
165 * The configuration data includes security contexts for
166 * initial SIDs, unlabeled file systems, TCP and UDP port numbers,
167 * network interfaces, and nodes. This structure stores the
168 * relevant data for one such entry. Entries of the same kind
169 * (e.g. all initial SIDs) are linked together into a list.
170 */
171 struct ocontext {
172 union {
173 char *name; /* name of initial SID, fs, netif, fstype, path */
174 struct {
175 u8 protocol;
176 u16 low_port;
177 u16 high_port;
178 } port; /* TCP or UDP port information */
179 struct {
180 u32 addr;
181 u32 mask;
182 } node; /* node information */
183 struct {
184 u32 addr[4];
185 u32 mask[4];
186 } node6; /* IPv6 node information */
187 struct {
188 u64 subnet_prefix;
189 u16 low_pkey;
190 u16 high_pkey;
191 } ibpkey;
192 struct {
193 char *dev_name;
194 u8 port;
195 } ibendport;
196 } u;
197 union {
198 u32 sclass; /* security class for genfs */
199 u32 behavior; /* labeling behavior for fs_use */
200 } v;
201 struct context context[2]; /* security context(s) */
202 u32 sid[2]; /* SID(s) */
203 struct ocontext *next;
204 };
205
206 struct genfs {
207 char *fstype;
208 struct ocontext *head;
209 struct genfs *next;
210 };
211
212 /* symbol table array indices */
213 #define SYM_COMMONS 0
214 #define SYM_CLASSES 1
215 #define SYM_ROLES 2
216 #define SYM_TYPES 3
217 #define SYM_USERS 4
218 #define SYM_BOOLS 5
219 #define SYM_LEVELS 6
220 #define SYM_CATS 7
221 #define SYM_NUM 8
222
223 /* object context array indices */
224 #define OCON_ISID 0 /* initial SIDs */
225 #define OCON_FS 1 /* unlabeled file systems (deprecated) */
226 #define OCON_PORT 2 /* TCP and UDP port numbers */
227 #define OCON_NETIF 3 /* network interfaces */
228 #define OCON_NODE 4 /* nodes */
229 #define OCON_FSUSE 5 /* fs_use */
230 #define OCON_NODE6 6 /* IPv6 nodes */
231 #define OCON_IBPKEY 7 /* Infiniband PKeys */
232 #define OCON_IBENDPORT 8 /* Infiniband end ports */
233 #define OCON_NUM 9
234
235 /* The policy database */
236 struct policydb {
237 int mls_enabled;
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 hashtab 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 /* only used if policyvers < POLICYDB_VERSION_COMP_FTRANS */
271 u32 compat_filename_trans_count;
272
273 /* bools indexed by (value - 1) */
274 struct cond_bool_datum **bool_val_to_struct;
275 /* type enforcement conditional access vectors and transitions */
276 struct avtab te_cond_avtab;
277 /* array indexing te_cond_avtab by conditional */
278 struct cond_node *cond_list;
279 u32 cond_list_len;
280
281 /* role allows */
282 struct role_allow *role_allow;
283
284 /* security contexts of initial SIDs, unlabeled file systems,
285 TCP or UDP port numbers, network interfaces and nodes */
286 struct ocontext *ocontexts[OCON_NUM];
287
288 /* security contexts for files in filesystems that cannot support
289 a persistent label mapping or use another
290 fixed labeling behavior. */
291 struct genfs *genfs;
292
293 /* range transitions table (range_trans_key -> mls_range) */
294 struct hashtab range_tr;
295
296 /* type -> attribute reverse mapping */
297 struct ebitmap *type_attr_map_array;
298
299 struct ebitmap policycaps;
300
301 struct ebitmap permissive_map;
302
303 struct ebitmap neveraudit_map;
304
305 /* length of this policy when it was loaded */
306 size_t len;
307
308 unsigned int policyvers;
309
310 unsigned int reject_unknown : 1;
311 unsigned int allow_unknown : 1;
312
313 u16 process_class;
314 u32 process_trans_perms;
315 } __randomize_layout;
316
317 struct policy_file {
318 char *data;
319 size_t len;
320 };
321
322 extern void policydb_destroy(struct policydb *p);
323 extern int policydb_load_isids(struct policydb *p, struct sidtab *s);
324 extern int policydb_context_isvalid(struct policydb *p, struct context *c);
325 extern int policydb_class_isvalid(struct policydb *p, unsigned int class);
326 extern int policydb_type_isvalid(struct policydb *p, unsigned int type);
327 extern int policydb_role_isvalid(struct policydb *p, unsigned int role);
328 extern int policydb_read(struct policydb *p, struct policy_file *fp);
329 extern int policydb_write(struct policydb *p, struct policy_file *fp);
330
331 extern struct filename_trans_datum *
332 policydb_filenametr_search(struct policydb *p, struct filename_trans_key *key);
333
334 extern struct mls_range *policydb_rangetr_search(struct policydb *p,
335 struct range_trans *key);
336
337 extern struct role_trans_datum *
338 policydb_roletr_search(struct policydb *p, struct role_trans_key *key);
339
340 #define POLICYDB_CONFIG_MLS 1
341
342 /* the config flags related to unknown classes/perms are bits 2 and 3 */
343 #define REJECT_UNKNOWN 0x00000002
344 #define ALLOW_UNKNOWN 0x00000004
345
346 #define OBJECT_R "object_r"
347 #define OBJECT_R_VAL 1
348
349 #define POLICYDB_MAGIC SELINUX_MAGIC
350 #define POLICYDB_STRING "SE Linux"
351
352 struct policy_data {
353 struct policydb *p;
354 struct policy_file *fp;
355 };
356
next_entry(void * buf,struct policy_file * fp,size_t bytes)357 static inline int next_entry(void *buf, struct policy_file *fp, size_t bytes)
358 {
359 if (bytes > fp->len)
360 return -EINVAL;
361
362 memcpy(buf, fp->data, bytes);
363 fp->data += bytes;
364 fp->len -= bytes;
365 return 0;
366 }
367
put_entry(const void * buf,size_t bytes,size_t num,struct policy_file * fp)368 static inline int put_entry(const void *buf, size_t bytes, size_t num,
369 struct policy_file *fp)
370 {
371 size_t len;
372
373 if (unlikely(check_mul_overflow(bytes, num, &len)))
374 return -EINVAL;
375
376 if (len > fp->len)
377 return -EINVAL;
378 memcpy(fp->data, buf, len);
379 fp->data += len;
380 fp->len -= len;
381
382 return 0;
383 }
384
sym_name(struct policydb * p,unsigned int sym_num,unsigned int element_nr)385 static inline char *sym_name(struct policydb *p, unsigned int sym_num,
386 unsigned int element_nr)
387 {
388 return p->sym_val_to_name[sym_num][element_nr];
389 }
390
391 extern int str_read(char **strp, gfp_t flags, struct policy_file *fp, u32 len);
392
393 extern u16 string_to_security_class(struct policydb *p, const char *name);
394 extern u32 string_to_av_perm(struct policydb *p, u16 tclass, const char *name);
395
396 #endif /* _SS_POLICYDB_H_ */
397