xref: /openbmc/linux/security/selinux/ss/policydb.h (revision b6dcefde)
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 "symtab.h"
28 #include "avtab.h"
29 #include "sidtab.h"
30 #include "context.h"
31 #include "constraint.h"
32 
33 /*
34  * A datum type is defined for each kind of symbol
35  * in the configuration data:  individual permissions,
36  * common prefixes for access vectors, classes,
37  * users, roles, types, sensitivities, categories, etc.
38  */
39 
40 /* Permission attributes */
41 struct perm_datum {
42 	u32 value;		/* permission bit + 1 */
43 };
44 
45 /* Attributes of a common prefix for access vectors */
46 struct common_datum {
47 	u32 value;			/* internal common value */
48 	struct symtab permissions;	/* common permissions */
49 };
50 
51 /* Class attributes */
52 struct class_datum {
53 	u32 value;			/* class value */
54 	char *comkey;			/* common name */
55 	struct common_datum *comdatum;	/* common datum */
56 	struct symtab permissions;	/* class-specific permission symbol table */
57 	struct constraint_node *constraints;	/* constraints on class permissions */
58 	struct constraint_node *validatetrans;	/* special transition rules */
59 };
60 
61 /* Role attributes */
62 struct role_datum {
63 	u32 value;			/* internal role value */
64 	u32 bounds;			/* boundary of role */
65 	struct ebitmap dominates;	/* set of roles dominated by this role */
66 	struct ebitmap types;		/* set of authorized types for role */
67 };
68 
69 struct role_trans {
70 	u32 role;		/* current role */
71 	u32 type;		/* program executable type */
72 	u32 new_role;		/* new role */
73 	struct role_trans *next;
74 };
75 
76 struct role_allow {
77 	u32 role;		/* current role */
78 	u32 new_role;		/* new role */
79 	struct role_allow *next;
80 };
81 
82 /* Type attributes */
83 struct type_datum {
84 	u32 value;		/* internal type value */
85 	u32 bounds;		/* boundary of type */
86 	unsigned char primary;	/* primary name? */
87 	unsigned char attribute;/* attribute ?*/
88 };
89 
90 /* User attributes */
91 struct user_datum {
92 	u32 value;			/* internal user value */
93 	u32 bounds;			/* bounds of user */
94 	struct ebitmap roles;		/* set of authorized roles for user */
95 	struct mls_range range;		/* MLS range (min - max) for user */
96 	struct mls_level dfltlevel;	/* default login MLS level for user */
97 };
98 
99 
100 /* Sensitivity attributes */
101 struct level_datum {
102 	struct mls_level *level;	/* sensitivity and associated categories */
103 	unsigned char isalias;	/* is this sensitivity an alias for another? */
104 };
105 
106 /* Category attributes */
107 struct cat_datum {
108 	u32 value;		/* internal category bit + 1 */
109 	unsigned char isalias;  /* is this category an alias for another? */
110 };
111 
112 struct range_trans {
113 	u32 source_type;
114 	u32 target_type;
115 	u32 target_class;
116 	struct mls_range target_range;
117 	struct range_trans *next;
118 };
119 
120 /* Boolean data type */
121 struct cond_bool_datum {
122 	__u32 value;		/* internal type value */
123 	int state;
124 };
125 
126 struct cond_node;
127 
128 /*
129  * The configuration data includes security contexts for
130  * initial SIDs, unlabeled file systems, TCP and UDP port numbers,
131  * network interfaces, and nodes.  This structure stores the
132  * relevant data for one such entry.  Entries of the same kind
133  * (e.g. all initial SIDs) are linked together into a list.
134  */
135 struct ocontext {
136 	union {
137 		char *name;	/* name of initial SID, fs, netif, fstype, path */
138 		struct {
139 			u8 protocol;
140 			u16 low_port;
141 			u16 high_port;
142 		} port;		/* TCP or UDP port information */
143 		struct {
144 			u32 addr;
145 			u32 mask;
146 		} node;		/* node information */
147 		struct {
148 			u32 addr[4];
149 			u32 mask[4];
150 		} node6;        /* IPv6 node information */
151 	} u;
152 	union {
153 		u32 sclass;  /* security class for genfs */
154 		u32 behavior;  /* labeling behavior for fs_use */
155 	} v;
156 	struct context context[2];	/* security context(s) */
157 	u32 sid[2];	/* SID(s) */
158 	struct ocontext *next;
159 };
160 
161 struct genfs {
162 	char *fstype;
163 	struct ocontext *head;
164 	struct genfs *next;
165 };
166 
167 /* symbol table array indices */
168 #define SYM_COMMONS 0
169 #define SYM_CLASSES 1
170 #define SYM_ROLES   2
171 #define SYM_TYPES   3
172 #define SYM_USERS   4
173 #define SYM_BOOLS   5
174 #define SYM_LEVELS  6
175 #define SYM_CATS    7
176 #define SYM_NUM     8
177 
178 /* object context array indices */
179 #define OCON_ISID  0	/* initial SIDs */
180 #define OCON_FS    1	/* unlabeled file systems */
181 #define OCON_PORT  2	/* TCP and UDP port numbers */
182 #define OCON_NETIF 3	/* network interfaces */
183 #define OCON_NODE  4	/* nodes */
184 #define OCON_FSUSE 5	/* fs_use */
185 #define OCON_NODE6 6	/* IPv6 nodes */
186 #define OCON_NUM   7
187 
188 /* The policy database */
189 struct policydb {
190 	/* symbol tables */
191 	struct symtab symtab[SYM_NUM];
192 #define p_commons symtab[SYM_COMMONS]
193 #define p_classes symtab[SYM_CLASSES]
194 #define p_roles symtab[SYM_ROLES]
195 #define p_types symtab[SYM_TYPES]
196 #define p_users symtab[SYM_USERS]
197 #define p_bools symtab[SYM_BOOLS]
198 #define p_levels symtab[SYM_LEVELS]
199 #define p_cats symtab[SYM_CATS]
200 
201 	/* symbol names indexed by (value - 1) */
202 	char **sym_val_to_name[SYM_NUM];
203 #define p_common_val_to_name sym_val_to_name[SYM_COMMONS]
204 #define p_class_val_to_name sym_val_to_name[SYM_CLASSES]
205 #define p_role_val_to_name sym_val_to_name[SYM_ROLES]
206 #define p_type_val_to_name sym_val_to_name[SYM_TYPES]
207 #define p_user_val_to_name sym_val_to_name[SYM_USERS]
208 #define p_bool_val_to_name sym_val_to_name[SYM_BOOLS]
209 #define p_sens_val_to_name sym_val_to_name[SYM_LEVELS]
210 #define p_cat_val_to_name sym_val_to_name[SYM_CATS]
211 
212 	/* class, role, and user attributes indexed by (value - 1) */
213 	struct class_datum **class_val_to_struct;
214 	struct role_datum **role_val_to_struct;
215 	struct user_datum **user_val_to_struct;
216 	struct type_datum **type_val_to_struct;
217 
218 	/* type enforcement access vectors and transitions */
219 	struct avtab te_avtab;
220 
221 	/* role transitions */
222 	struct role_trans *role_tr;
223 
224 	/* bools indexed by (value - 1) */
225 	struct cond_bool_datum **bool_val_to_struct;
226 	/* type enforcement conditional access vectors and transitions */
227 	struct avtab te_cond_avtab;
228 	/* linked list indexing te_cond_avtab by conditional */
229 	struct cond_node *cond_list;
230 
231 	/* role allows */
232 	struct role_allow *role_allow;
233 
234 	/* security contexts of initial SIDs, unlabeled file systems,
235 	   TCP or UDP port numbers, network interfaces and nodes */
236 	struct ocontext *ocontexts[OCON_NUM];
237 
238 	/* security contexts for files in filesystems that cannot support
239 	   a persistent label mapping or use another
240 	   fixed labeling behavior. */
241 	struct genfs *genfs;
242 
243 	/* range transitions */
244 	struct range_trans *range_tr;
245 
246 	/* type -> attribute reverse mapping */
247 	struct ebitmap *type_attr_map;
248 
249 	struct ebitmap policycaps;
250 
251 	struct ebitmap permissive_map;
252 
253 	unsigned int policyvers;
254 
255 	unsigned int reject_unknown : 1;
256 	unsigned int allow_unknown : 1;
257 
258 	u16 process_class;
259 	u32 process_trans_perms;
260 };
261 
262 extern void policydb_destroy(struct policydb *p);
263 extern int policydb_load_isids(struct policydb *p, struct sidtab *s);
264 extern int policydb_context_isvalid(struct policydb *p, struct context *c);
265 extern int policydb_class_isvalid(struct policydb *p, unsigned int class);
266 extern int policydb_type_isvalid(struct policydb *p, unsigned int type);
267 extern int policydb_role_isvalid(struct policydb *p, unsigned int role);
268 extern int policydb_read(struct policydb *p, void *fp);
269 
270 #define PERM_SYMTAB_SIZE 32
271 
272 #define POLICYDB_CONFIG_MLS    1
273 
274 /* the config flags related to unknown classes/perms are bits 2 and 3 */
275 #define REJECT_UNKNOWN	0x00000002
276 #define ALLOW_UNKNOWN	0x00000004
277 
278 #define OBJECT_R "object_r"
279 #define OBJECT_R_VAL 1
280 
281 #define POLICYDB_MAGIC SELINUX_MAGIC
282 #define POLICYDB_STRING "SE Linux"
283 
284 struct policy_file {
285 	char *data;
286 	size_t len;
287 };
288 
289 static inline int next_entry(void *buf, struct policy_file *fp, size_t bytes)
290 {
291 	if (bytes > fp->len)
292 		return -EINVAL;
293 
294 	memcpy(buf, fp->data, bytes);
295 	fp->data += bytes;
296 	fp->len -= bytes;
297 	return 0;
298 }
299 
300 extern u16 string_to_security_class(struct policydb *p, const char *name);
301 extern u32 string_to_av_perm(struct policydb *p, u16 tclass, const char *name);
302 
303 #endif	/* _SS_POLICYDB_H_ */
304 
305