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, <stephen.smalley.work@gmail.com>
15 */
16
17#ifndef _SS_CONSTRAINT_H_
18#define _SS_CONSTRAINT_H_
19
20#include "ebitmap.h"
21
22#define CEXPR_MAXDEPTH 5
23
24struct constraint_expr {
25#define CEXPR_NOT   1 /* not expr */
26#define CEXPR_AND   2 /* expr and expr */
27#define CEXPR_OR    3 /* expr or expr */
28#define CEXPR_ATTR  4 /* attr op attr */
29#define CEXPR_NAMES 5 /* attr op names */
30	u32 expr_type; /* expression type */
31
32#define CEXPR_USER    1 /* user */
33#define CEXPR_ROLE    2 /* role */
34#define CEXPR_TYPE    4 /* type */
35#define CEXPR_TARGET  8 /* target if set, source otherwise */
36#define CEXPR_XTARGET 16 /* special 3rd target for validatetrans rule */
37#define CEXPR_L1L2    32 /* low level 1 vs. low level 2 */
38#define CEXPR_L1H2    64 /* low level 1 vs. high level 2 */
39#define CEXPR_H1L2    128 /* high level 1 vs. low level 2 */
40#define CEXPR_H1H2    256 /* high level 1 vs. high level 2 */
41#define CEXPR_L1H1    512 /* low level 1 vs. high level 1 */
42#define CEXPR_L2H2    1024 /* low level 2 vs. high level 2 */
43	u32 attr; /* attribute */
44
45#define CEXPR_EQ     1 /* == or eq */
46#define CEXPR_NEQ    2 /* != */
47#define CEXPR_DOM    3 /* dom */
48#define CEXPR_DOMBY  4 /* domby  */
49#define CEXPR_INCOMP 5 /* incomp */
50	u32 op; /* operator */
51
52	struct ebitmap names; /* names */
53	struct type_set *type_names;
54
55	struct constraint_expr *next; /* next expression */
56};
57
58struct constraint_node {
59	u32 permissions; /* constrained permissions */
60	struct constraint_expr *expr; /* constraint on permissions */
61	struct constraint_node *next; /* next constraint */
62};
63
64#endif /* _SS_CONSTRAINT_H_ */
65