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