1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * A constraint is a condition that must be satisfied in
4 * order for one or more permissions to be granted.
5 * Constraints are used to impose additional restrictions
6 * beyond the type-based rules in `te' or the role-based
7 * transition rules in `rbac'. Constraints are typically
8 * used to prevent a process from transitioning to a new user
9 * identity or role unless it is in a privileged type.
10 * Constraints are likewise typically used to prevent a
11 * process from labeling an object with a different user
12 * identity.
13 *
14 * Author : Stephen Smalley, <sds@tycho.nsa.gov>
15 */
16 #ifndef _SS_CONSTRAINT_H_
17 #define _SS_CONSTRAINT_H_
18
19 #include "ebitmap.h"
20
21 #define CEXPR_MAXDEPTH 5
22
23 struct constraint_expr {
24 #define CEXPR_NOT 1 /* not expr */
25 #define CEXPR_AND 2 /* expr and expr */
26 #define CEXPR_OR 3 /* expr or expr */
27 #define CEXPR_ATTR 4 /* attr op attr */
28 #define CEXPR_NAMES 5 /* attr op names */
29 u32 expr_type; /* expression type */
30
31 #define CEXPR_USER 1 /* user */
32 #define CEXPR_ROLE 2 /* role */
33 #define CEXPR_TYPE 4 /* type */
34 #define CEXPR_TARGET 8 /* target if set, source otherwise */
35 #define CEXPR_XTARGET 16 /* special 3rd target for validatetrans rule */
36 #define CEXPR_L1L2 32 /* low level 1 vs. low level 2 */
37 #define CEXPR_L1H2 64 /* low level 1 vs. high level 2 */
38 #define CEXPR_H1L2 128 /* high level 1 vs. low level 2 */
39 #define CEXPR_H1H2 256 /* high level 1 vs. high level 2 */
40 #define CEXPR_L1H1 512 /* low level 1 vs. high level 1 */
41 #define CEXPR_L2H2 1024 /* low level 2 vs. high level 2 */
42 u32 attr; /* attribute */
43
44 #define CEXPR_EQ 1 /* == or eq */
45 #define CEXPR_NEQ 2 /* != */
46 #define CEXPR_DOM 3 /* dom */
47 #define CEXPR_DOMBY 4 /* domby */
48 #define CEXPR_INCOMP 5 /* incomp */
49 u32 op; /* operator */
50
51 struct ebitmap names; /* names */
52 struct type_set *type_names;
53
54 struct constraint_expr *next; /* next expression */
55 };
56
57 struct constraint_node {
58 u32 permissions; /* constrained permissions */
59 struct constraint_expr *expr; /* constraint on permissions */
60 struct constraint_node *next; /* next constraint */
61 };
62
63 #endif /* _SS_CONSTRAINT_H_ */