1/* 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 11 * identity. 12 * 13 * Author : Stephen Smalley, <sds@epoch.ncsc.mil> 14 */ 15#ifndef _SS_CONSTRAINT_H_ 16#define _SS_CONSTRAINT_H_ 17 18#include "ebitmap.h" 19 20#define CEXPR_MAXDEPTH 5 21 22struct 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 */ 29 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 */ 42 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 */ 49 50 struct ebitmap names; /* names */ 51 52 struct constraint_expr *next; /* next expression */ 53}; 54 55struct constraint_node { 56 u32 permissions; /* constrained permissions */ 57 struct constraint_expr *expr; /* constraint on permissions */ 58 struct constraint_node *next; /* next constraint */ 59}; 60 61#endif /* _SS_CONSTRAINT_H_ */ 62