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 */
76 u32 new_role; /* new role */
77 struct role_trans *next;
78 };
79
80 struct filename_trans {
81 struct filename_trans *next;
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 u32 otype; /* expected of new object */
87 };
88
89 struct role_allow {
90 u32 role; /* current role */
91 u32 new_role; /* new role */
92 struct role_allow *next;
93 };
94
95 /* Type attributes */
96 struct type_datum {
97 u32 value; /* internal type value */
98 u32 bounds; /* boundary of type */
99 unsigned char primary; /* primary name? */
100 unsigned char attribute;/* attribute ?*/
101 };
102
103 /* User attributes */
104 struct user_datum {
105 u32 value; /* internal user value */
106 u32 bounds; /* bounds of user */
107 struct ebitmap roles; /* set of authorized roles for user */
108 struct mls_range range; /* MLS range (min - max) for user */
109 struct mls_level dfltlevel; /* default login MLS level for user */
110 };
111
112
113 /* Sensitivity attributes */
114 struct level_datum {
115 struct mls_level *level; /* sensitivity and associated categories */
116 unsigned char isalias; /* is this sensitivity an alias for another? */
117 };
118
119 /* Category attributes */
120 struct cat_datum {
121 u32 value; /* internal category bit + 1 */
122 unsigned char isalias; /* is this category an alias for another? */
123 };
124
125 struct range_trans {
126 u32 source_type;
127 u32 target_type;
128 u32 target_class;
129 };
130
131 /* Boolean data type */
132 struct cond_bool_datum {
133 __u32 value; /* internal type value */
134 int state;
135 };
136
137 struct cond_node;
138
139 /*
140 * The configuration data includes security contexts for
141 * initial SIDs, unlabeled file systems, TCP and UDP port numbers,
142 * network interfaces, and nodes. This structure stores the
143 * relevant data for one such entry. Entries of the same kind
144 * (e.g. all initial SIDs) are linked together into a list.
145 */
146 struct ocontext {
147 union {
148 char *name; /* name of initial SID, fs, netif, fstype, path */
149 struct {
150 u8 protocol;
151 u16 low_port;
152 u16 high_port;
153 } port; /* TCP or UDP port information */
154 struct {
155 u32 addr;
156 u32 mask;
157 } node; /* node information */
158 struct {
159 u32 addr[4];
160 u32 mask[4];
161 } node6; /* IPv6 node information */
162 } u;
163 union {
164 u32 sclass; /* security class for genfs */
165 u32 behavior; /* labeling behavior for fs_use */
166 } v;
167 struct context context[2]; /* security context(s) */
168 u32 sid[2]; /* SID(s) */
169 struct ocontext *next;
170 };
171
172 struct genfs {
173 char *fstype;
174 struct ocontext *head;
175 struct genfs *next;
176 };
177
178 /* symbol table array indices */
179 #define SYM_COMMONS 0
180 #define SYM_CLASSES 1
181 #define SYM_ROLES 2
182 #define SYM_TYPES 3
183 #define SYM_USERS 4
184 #define SYM_BOOLS 5
185 #define SYM_LEVELS 6
186 #define SYM_CATS 7
187 #define SYM_NUM 8
188
189 /* object context array indices */
190 #define OCON_ISID 0 /* initial SIDs */
191 #define OCON_FS 1 /* unlabeled file systems */
192 #define OCON_PORT 2 /* TCP and UDP port numbers */
193 #define OCON_NETIF 3 /* network interfaces */
194 #define OCON_NODE 4 /* nodes */
195 #define OCON_FSUSE 5 /* fs_use */
196 #define OCON_NODE6 6 /* IPv6 nodes */
197 #define OCON_NUM 7
198
199 /* The policy database */
200 struct policydb {
201 int mls_enabled;
202
203 /* symbol tables */
204 struct symtab symtab[SYM_NUM];
205 #define p_commons symtab[SYM_COMMONS]
206 #define p_classes symtab[SYM_CLASSES]
207 #define p_roles symtab[SYM_ROLES]
208 #define p_types symtab[SYM_TYPES]
209 #define p_users symtab[SYM_USERS]
210 #define p_bools symtab[SYM_BOOLS]
211 #define p_levels symtab[SYM_LEVELS]
212 #define p_cats symtab[SYM_CATS]
213
214 /* symbol names indexed by (value - 1) */
215 struct flex_array *sym_val_to_name[SYM_NUM];
216
217 /* class, role, and user attributes indexed by (value - 1) */
218 struct class_datum **class_val_to_struct;
219 struct role_datum **role_val_to_struct;
220 struct user_datum **user_val_to_struct;
221 struct flex_array *type_val_to_struct_array;
222
223 /* type enforcement access vectors and transitions */
224 struct avtab te_avtab;
225
226 /* role transitions */
227 struct role_trans *role_tr;
228
229 /* file transitions with the last path component */
230 struct filename_trans *filename_trans;
231
232 /* bools indexed by (value - 1) */
233 struct cond_bool_datum **bool_val_to_struct;
234 /* type enforcement conditional access vectors and transitions */
235 struct avtab te_cond_avtab;
236 /* linked list indexing te_cond_avtab by conditional */
237 struct cond_node *cond_list;
238
239 /* role allows */
240 struct role_allow *role_allow;
241
242 /* security contexts of initial SIDs, unlabeled file systems,
243 TCP or UDP port numbers, network interfaces and nodes */
244 struct ocontext *ocontexts[OCON_NUM];
245
246 /* security contexts for files in filesystems that cannot support
247 a persistent label mapping or use another
248 fixed labeling behavior. */
249 struct genfs *genfs;
250
251 /* range transitions table (range_trans_key -> mls_range) */
252 struct hashtab *range_tr;
253
254 /* type -> attribute reverse mapping */
255 struct flex_array *type_attr_map_array;
256
257 struct ebitmap policycaps;
258
259 struct ebitmap permissive_map;
260
261 /* length of this policy when it was loaded */
262 size_t len;
263
264 unsigned int policyvers;
265
266 unsigned int reject_unknown : 1;
267 unsigned int allow_unknown : 1;
268
269 u16 process_class;
270 u32 process_trans_perms;
271 };
272
273 extern void policydb_destroy(struct policydb *p);
274 extern int policydb_load_isids(struct policydb *p, struct sidtab *s);
275 extern int policydb_context_isvalid(struct policydb *p, struct context *c);
276 extern int policydb_class_isvalid(struct policydb *p, unsigned int class);
277 extern int policydb_type_isvalid(struct policydb *p, unsigned int type);
278 extern int policydb_role_isvalid(struct policydb *p, unsigned int role);
279 extern int policydb_read(struct policydb *p, void *fp);
280 extern int policydb_write(struct policydb *p, void *fp);
281
282 #define PERM_SYMTAB_SIZE 32
283
284 #define POLICYDB_CONFIG_MLS 1
285
286 /* the config flags related to unknown classes/perms are bits 2 and 3 */
287 #define REJECT_UNKNOWN 0x00000002
288 #define ALLOW_UNKNOWN 0x00000004
289
290 #define OBJECT_R "object_r"
291 #define OBJECT_R_VAL 1
292
293 #define POLICYDB_MAGIC SELINUX_MAGIC
294 #define POLICYDB_STRING "SE Linux"
295
296 struct policy_file {
297 char *data;
298 size_t len;
299 };
300
301 struct policy_data {
302 struct policydb *p;
303 void *fp;
304 };
305
next_entry(void * buf,struct policy_file * fp,size_t bytes)306 static inline int next_entry(void *buf, struct policy_file *fp, size_t bytes)
307 {
308 if (bytes > fp->len)
309 return -EINVAL;
310
311 memcpy(buf, fp->data, bytes);
312 fp->data += bytes;
313 fp->len -= bytes;
314 return 0;
315 }
316
put_entry(const void * buf,size_t bytes,int num,struct policy_file * fp)317 static inline int put_entry(const void *buf, size_t bytes, int num, struct policy_file *fp)
318 {
319 size_t len = bytes * num;
320
321 memcpy(fp->data, buf, len);
322 fp->data += len;
323 fp->len -= len;
324
325 return 0;
326 }
327
sym_name(struct policydb * p,unsigned int sym_num,unsigned int element_nr)328 static inline char *sym_name(struct policydb *p, unsigned int sym_num, unsigned int element_nr)
329 {
330 struct flex_array *fa = p->sym_val_to_name[sym_num];
331
332 return flex_array_get_ptr(fa, element_nr);
333 }
334
335 extern u16 string_to_security_class(struct policydb *p, const char *name);
336 extern u32 string_to_av_perm(struct policydb *p, u16 tclass, const char *name);
337
338 #endif /* _SS_POLICYDB_H_ */
339
340