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 */
45struct perm_datum {
46	u32 value;		/* permission bit + 1 */
47};
48
49/* Attributes of a common prefix for access vectors */
50struct common_datum {
51	u32 value;			/* internal common value */
52	struct symtab permissions;	/* common permissions */
53};
54
55/* Class attributes */
56struct 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 */
80struct 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
87struct 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
95struct 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
102struct filename_trans_datum {
103	u32 otype;		/* expected of new object */
104};
105
106struct role_allow {
107	u32 role;		/* current role */
108	u32 new_role;		/* new role */
109	struct role_allow *next;
110};
111
112/* Type attributes */
113struct 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 */
121struct 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 */
131struct 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 */
137struct cat_datum {
138	u32 value;		/* internal category bit + 1 */
139	unsigned char isalias;  /* is this category an alias for another? */
140};
141
142struct range_trans {
143	u32 source_type;
144	u32 target_type;
145	u32 target_class;
146};
147
148/* Boolean data type */
149struct cond_bool_datum {
150	__u32 value;		/* internal type value */
151	int state;
152};
153
154struct 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 */
161struct 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 */
174struct 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	} u;
191	union {
192		u32 sclass;  /* security class for genfs */
193		u32 behavior;  /* labeling behavior for fs_use */
194	} v;
195	struct context context[2];	/* security context(s) */
196	u32 sid[2];	/* SID(s) */
197	struct ocontext *next;
198};
199
200struct genfs {
201	char *fstype;
202	struct ocontext *head;
203	struct genfs *next;
204};
205
206/* symbol table array indices */
207#define SYM_COMMONS 0
208#define SYM_CLASSES 1
209#define SYM_ROLES   2
210#define SYM_TYPES   3
211#define SYM_USERS   4
212#define SYM_BOOLS   5
213#define SYM_LEVELS  6
214#define SYM_CATS    7
215#define SYM_NUM     8
216
217/* object context array indices */
218#define OCON_ISID  0	/* initial SIDs */
219#define OCON_FS    1	/* unlabeled file systems */
220#define OCON_PORT  2	/* TCP and UDP port numbers */
221#define OCON_NETIF 3	/* network interfaces */
222#define OCON_NODE  4	/* nodes */
223#define OCON_FSUSE 5	/* fs_use */
224#define OCON_NODE6 6	/* IPv6 nodes */
225#define OCON_NUM   7
226
227/* The policy database */
228struct policydb {
229	int mls_enabled;
230
231	/* symbol tables */
232	struct symtab symtab[SYM_NUM];
233#define p_commons symtab[SYM_COMMONS]
234#define p_classes symtab[SYM_CLASSES]
235#define p_roles symtab[SYM_ROLES]
236#define p_types symtab[SYM_TYPES]
237#define p_users symtab[SYM_USERS]
238#define p_bools symtab[SYM_BOOLS]
239#define p_levels symtab[SYM_LEVELS]
240#define p_cats symtab[SYM_CATS]
241
242	/* symbol names indexed by (value - 1) */
243	struct flex_array *sym_val_to_name[SYM_NUM];
244
245	/* class, role, and user attributes indexed by (value - 1) */
246	struct class_datum **class_val_to_struct;
247	struct role_datum **role_val_to_struct;
248	struct user_datum **user_val_to_struct;
249	struct flex_array *type_val_to_struct_array;
250
251	/* type enforcement access vectors and transitions */
252	struct avtab te_avtab;
253
254	/* role transitions */
255	struct role_trans *role_tr;
256
257	/* file transitions with the last path component */
258	/* quickly exclude lookups when parent ttype has no rules */
259	struct ebitmap filename_trans_ttypes;
260	/* actual set of filename_trans rules */
261	struct hashtab *filename_trans;
262
263	/* bools indexed by (value - 1) */
264	struct cond_bool_datum **bool_val_to_struct;
265	/* type enforcement conditional access vectors and transitions */
266	struct avtab te_cond_avtab;
267	/* linked list indexing te_cond_avtab by conditional */
268	struct cond_node *cond_list;
269
270	/* role allows */
271	struct role_allow *role_allow;
272
273	/* security contexts of initial SIDs, unlabeled file systems,
274	   TCP or UDP port numbers, network interfaces and nodes */
275	struct ocontext *ocontexts[OCON_NUM];
276
277	/* security contexts for files in filesystems that cannot support
278	   a persistent label mapping or use another
279	   fixed labeling behavior. */
280	struct genfs *genfs;
281
282	/* range transitions table (range_trans_key -> mls_range) */
283	struct hashtab *range_tr;
284
285	/* type -> attribute reverse mapping */
286	struct flex_array *type_attr_map_array;
287
288	struct ebitmap policycaps;
289
290	struct ebitmap permissive_map;
291
292	/* length of this policy when it was loaded */
293	size_t len;
294
295	unsigned int policyvers;
296
297	unsigned int reject_unknown : 1;
298	unsigned int allow_unknown : 1;
299
300	u16 process_class;
301	u32 process_trans_perms;
302};
303
304extern void policydb_destroy(struct policydb *p);
305extern int policydb_load_isids(struct policydb *p, struct sidtab *s);
306extern int policydb_context_isvalid(struct policydb *p, struct context *c);
307extern int policydb_class_isvalid(struct policydb *p, unsigned int class);
308extern int policydb_type_isvalid(struct policydb *p, unsigned int type);
309extern int policydb_role_isvalid(struct policydb *p, unsigned int role);
310extern int policydb_read(struct policydb *p, void *fp);
311extern int policydb_write(struct policydb *p, void *fp);
312
313#define PERM_SYMTAB_SIZE 32
314
315#define POLICYDB_CONFIG_MLS    1
316
317/* the config flags related to unknown classes/perms are bits 2 and 3 */
318#define REJECT_UNKNOWN	0x00000002
319#define ALLOW_UNKNOWN	0x00000004
320
321#define OBJECT_R "object_r"
322#define OBJECT_R_VAL 1
323
324#define POLICYDB_MAGIC SELINUX_MAGIC
325#define POLICYDB_STRING "SE Linux"
326
327struct policy_file {
328	char *data;
329	size_t len;
330};
331
332struct policy_data {
333	struct policydb *p;
334	void *fp;
335};
336
337static inline int next_entry(void *buf, struct policy_file *fp, size_t bytes)
338{
339	if (bytes > fp->len)
340		return -EINVAL;
341
342	memcpy(buf, fp->data, bytes);
343	fp->data += bytes;
344	fp->len -= bytes;
345	return 0;
346}
347
348static inline int put_entry(const void *buf, size_t bytes, int num, struct policy_file *fp)
349{
350	size_t len = bytes * num;
351
352	memcpy(fp->data, buf, len);
353	fp->data += len;
354	fp->len -= len;
355
356	return 0;
357}
358
359static inline char *sym_name(struct policydb *p, unsigned int sym_num, unsigned int element_nr)
360{
361	struct flex_array *fa = p->sym_val_to_name[sym_num];
362
363	return flex_array_get_ptr(fa, element_nr);
364}
365
366extern u16 string_to_security_class(struct policydb *p, const char *name);
367extern u32 string_to_av_perm(struct policydb *p, u16 tclass, const char *name);
368
369#endif	/* _SS_POLICYDB_H_ */
370
371