1/* Authors: Karl MacMillan <kmacmillan@tresys.com> 2 * Frank Mayer <mayerf@tresys.com> 3 * 4 * Copyright (C) 2003 - 2004 Tresys Technology, LLC 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License as published by 7 * the Free Software Foundation, version 2. 8 */ 9 10#ifndef _CONDITIONAL_H_ 11#define _CONDITIONAL_H_ 12 13#include "avtab.h" 14#include "symtab.h" 15#include "policydb.h" 16 17#define COND_EXPR_MAXDEPTH 10 18 19/* 20 * A conditional expression is a list of operators and operands 21 * in reverse polish notation. 22 */ 23struct cond_expr { 24#define COND_BOOL 1 /* plain bool */ 25#define COND_NOT 2 /* !bool */ 26#define COND_OR 3 /* bool || bool */ 27#define COND_AND 4 /* bool && bool */ 28#define COND_XOR 5 /* bool ^ bool */ 29#define COND_EQ 6 /* bool == bool */ 30#define COND_NEQ 7 /* bool != bool */ 31#define COND_LAST COND_NEQ 32 __u32 expr_type; 33 __u32 bool; 34 struct cond_expr *next; 35}; 36 37/* 38 * Each cond_node contains a list of rules to be enabled/disabled 39 * depending on the current value of the conditional expression. This 40 * struct is for that list. 41 */ 42struct cond_av_list { 43 struct avtab_node *node; 44 struct cond_av_list *next; 45}; 46 47/* 48 * A cond node represents a conditional block in a policy. It 49 * contains a conditional expression, the current state of the expression, 50 * two lists of rules to enable/disable depending on the value of the 51 * expression (the true list corresponds to if and the false list corresponds 52 * to else).. 53 */ 54struct cond_node { 55 int cur_state; 56 struct cond_expr *expr; 57 struct cond_av_list *true_list; 58 struct cond_av_list *false_list; 59 struct cond_node *next; 60}; 61 62int cond_policydb_init(struct policydb *p); 63void cond_policydb_destroy(struct policydb *p); 64 65int cond_init_bool_indexes(struct policydb *p); 66int cond_destroy_bool(void *key, void *datum, void *p); 67 68int cond_index_bool(void *key, void *datum, void *datap); 69 70int cond_read_bool(struct policydb *p, struct hashtab *h, void *fp); 71int cond_read_list(struct policydb *p, void *fp); 72 73void cond_compute_av(struct avtab *ctab, struct avtab_key *key, struct av_decision *avd); 74 75int evaluate_cond_node(struct policydb *p, struct cond_node *node); 76 77#endif /* _CONDITIONAL_H_ */ 78