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 #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_ */ 64