1 /*
2 * A policy database (policydb) specifies the
3 * configuration data for the security policy.
4 *
5 * Author : Stephen Smalley, <sds@epoch.ncsc.mil>
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 };
64
65 /* Role attributes */
66 struct role_datum {
67 u32 value; /* internal role value */
68 u32 bounds; /* boundary of role */
69 struct ebitmap dominates; /* set of roles dominated by this role */
70 struct ebitmap types; /* set of authorized types for role */
71 };
72
73 struct role_trans {
74 u32 role; /* current role */
75 u32 type; /* program executable type, or new object type */
76 u32 tclass; /* process class, or new object class */
77 u32 new_role; /* new role */
78 struct role_trans *next;
79 };
80
81 struct filename_trans {
82 u32 stype; /* current process */
83 u32 ttype; /* parent dir context */
84 u16 tclass; /* class of new object */
85 const char *name; /* last path component */
86 };
87
88 struct filename_trans_datum {
89 u32 otype; /* expected of new object */
90 };
91
92 struct role_allow {
93 u32 role; /* current role */
94 u32 new_role; /* new role */
95 struct role_allow *next;
96 };
97
98 /* Type attributes */
99 struct type_datum {
100 u32 value; /* internal type value */
101 u32 bounds; /* boundary of type */
102 unsigned char primary; /* primary name? */
103 unsigned char attribute;/* attribute ?*/
104 };
105
106 /* User attributes */
107 struct user_datum {
108 u32 value; /* internal user value */
109 u32 bounds; /* bounds of user */
110 struct ebitmap roles; /* set of authorized roles for user */
111 struct mls_range range; /* MLS range (min - max) for user */
112 struct mls_level dfltlevel; /* default login MLS level for user */
113 };
114
115
116 /* Sensitivity attributes */
117 struct level_datum {
118 struct mls_level *level; /* sensitivity and associated categories */
119 unsigned char isalias; /* is this sensitivity an alias for another? */
120 };
121
122 /* Category attributes */
123 struct cat_datum {
124 u32 value; /* internal category bit + 1 */
125 unsigned char isalias; /* is this category an alias for another? */
126 };
127
128 struct range_trans {
129 u32 source_type;
130 u32 target_type;
131 u32 target_class;
132 };
133
134 /* Boolean data type */
135 struct cond_bool_datum {
136 __u32 value; /* internal type value */
137 int state;
138 };
139
140 struct cond_node;
141
142 /*
143 * The configuration data includes security contexts for
144 * initial SIDs, unlabeled file systems, TCP and UDP port numbers,
145 * network interfaces, and nodes. This structure stores the
146 * relevant data for one such entry. Entries of the same kind
147 * (e.g. all initial SIDs) are linked together into a list.
148 */
149 struct ocontext {
150 union {
151 char *name; /* name of initial SID, fs, netif, fstype, path */
152 struct {
153 u8 protocol;
154 u16 low_port;
155 u16 high_port;
156 } port; /* TCP or UDP port information */
157 struct {
158 u32 addr;
159 u32 mask;
160 } node; /* node information */
161 struct {
162 u32 addr[4];
163 u32 mask[4];
164 } node6; /* IPv6 node information */
165 } u;
166 union {
167 u32 sclass; /* security class for genfs */
168 u32 behavior; /* labeling behavior for fs_use */
169 } v;
170 struct context context[2]; /* security context(s) */
171 u32 sid[2]; /* SID(s) */
172 struct ocontext *next;
173 };
174
175 struct genfs {
176 char *fstype;
177 struct ocontext *head;
178 struct genfs *next;
179 };
180
181 /* symbol table array indices */
182 #define SYM_COMMONS 0
183 #define SYM_CLASSES 1
184 #define SYM_ROLES 2
185 #define SYM_TYPES 3
186 #define SYM_USERS 4
187 #define SYM_BOOLS 5
188 #define SYM_LEVELS 6
189 #define SYM_CATS 7
190 #define SYM_NUM 8
191
192 /* object context array indices */
193 #define OCON_ISID 0 /* initial SIDs */
194 #define OCON_FS 1 /* unlabeled file systems */
195 #define OCON_PORT 2 /* TCP and UDP port numbers */
196 #define OCON_NETIF 3 /* network interfaces */
197 #define OCON_NODE 4 /* nodes */
198 #define OCON_FSUSE 5 /* fs_use */
199 #define OCON_NODE6 6 /* IPv6 nodes */
200 #define OCON_NUM 7
201
202 /* The policy database */
203 struct policydb {
204 int mls_enabled;
205
206 /* symbol tables */
207 struct symtab symtab[SYM_NUM];
208 #define p_commons symtab[SYM_COMMONS]
209 #define p_classes symtab[SYM_CLASSES]
210 #define p_roles symtab[SYM_ROLES]
211 #define p_types symtab[SYM_TYPES]
212 #define p_users symtab[SYM_USERS]
213 #define p_bools symtab[SYM_BOOLS]
214 #define p_levels symtab[SYM_LEVELS]
215 #define p_cats symtab[SYM_CATS]
216
217 /* symbol names indexed by (value - 1) */
218 struct flex_array *sym_val_to_name[SYM_NUM];
219
220 /* class, role, and user attributes indexed by (value - 1) */
221 struct class_datum **class_val_to_struct;
222 struct role_datum **role_val_to_struct;
223 struct user_datum **user_val_to_struct;
224 struct flex_array *type_val_to_struct_array;
225
226 /* type enforcement access vectors and transitions */
227 struct avtab te_avtab;
228
229 /* role transitions */
230 struct role_trans *role_tr;
231
232 /* file transitions with the last path component */
233 /* quickly exclude lookups when parent ttype has no rules */
234 struct ebitmap filename_trans_ttypes;
235 /* actual set of filename_trans rules */
236 struct hashtab *filename_trans;
237
238 /* bools indexed by (value - 1) */
239 struct cond_bool_datum **bool_val_to_struct;
240 /* type enforcement conditional access vectors and transitions */
241 struct avtab te_cond_avtab;
242 /* linked list indexing te_cond_avtab by conditional */
243 struct cond_node *cond_list;
244
245 /* role allows */
246 struct role_allow *role_allow;
247
248 /* security contexts of initial SIDs, unlabeled file systems,
249 TCP or UDP port numbers, network interfaces and nodes */
250 struct ocontext *ocontexts[OCON_NUM];
251
252 /* security contexts for files in filesystems that cannot support
253 a persistent label mapping or use another
254 fixed labeling behavior. */
255 struct genfs *genfs;
256
257 /* range transitions table (range_trans_key -> mls_range) */
258 struct hashtab *range_tr;
259
260 /* type -> attribute reverse mapping */
261 struct flex_array *type_attr_map_array;
262
263 struct ebitmap policycaps;
264
265 struct ebitmap permissive_map;
266
267 /* length of this policy when it was loaded */
268 size_t len;
269
270 unsigned int policyvers;
271
272 unsigned int reject_unknown : 1;
273 unsigned int allow_unknown : 1;
274
275 u16 process_class;
276 u32 process_trans_perms;
277 };
278
279 extern void policydb_destroy(struct policydb *p);
280 extern int policydb_load_isids(struct policydb *p, struct sidtab *s);
281 extern int policydb_context_isvalid(struct policydb *p, struct context *c);
282 extern int policydb_class_isvalid(struct policydb *p, unsigned int class);
283 extern int policydb_type_isvalid(struct policydb *p, unsigned int type);
284 extern int policydb_role_isvalid(struct policydb *p, unsigned int role);
285 extern int policydb_read(struct policydb *p, void *fp);
286 extern int policydb_write(struct policydb *p, void *fp);
287
288 #define PERM_SYMTAB_SIZE 32
289
290 #define POLICYDB_CONFIG_MLS 1
291
292 /* the config flags related to unknown classes/perms are bits 2 and 3 */
293 #define REJECT_UNKNOWN 0x00000002
294 #define ALLOW_UNKNOWN 0x00000004
295
296 #define OBJECT_R "object_r"
297 #define OBJECT_R_VAL 1
298
299 #define POLICYDB_MAGIC SELINUX_MAGIC
300 #define POLICYDB_STRING "SE Linux"
301
302 struct policy_file {
303 char *data;
304 size_t len;
305 };
306
307 struct policy_data {
308 struct policydb *p;
309 void *fp;
310 };
311
next_entry(void * buf,struct policy_file * fp,size_t bytes)312 static inline int next_entry(void *buf, struct policy_file *fp, size_t bytes)
313 {
314 if (bytes > fp->len)
315 return -EINVAL;
316
317 memcpy(buf, fp->data, bytes);
318 fp->data += bytes;
319 fp->len -= bytes;
320 return 0;
321 }
322
put_entry(const void * buf,size_t bytes,int num,struct policy_file * fp)323 static inline int put_entry(const void *buf, size_t bytes, int num, struct policy_file *fp)
324 {
325 size_t len = bytes * num;
326
327 memcpy(fp->data, buf, len);
328 fp->data += len;
329 fp->len -= len;
330
331 return 0;
332 }
333
sym_name(struct policydb * p,unsigned int sym_num,unsigned int element_nr)334 static inline char *sym_name(struct policydb *p, unsigned int sym_num, unsigned int element_nr)
335 {
336 struct flex_array *fa = p->sym_val_to_name[sym_num];
337
338 return flex_array_get_ptr(fa, element_nr);
339 }
340
341 extern u16 string_to_security_class(struct policydb *p, const char *name);
342 extern u32 string_to_av_perm(struct policydb *p, u16 tclass, const char *name);
343
344 #endif /* _SS_POLICYDB_H_ */
345
346