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 */ 23 struct 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 8 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 */ 42 struct 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 */ 54 struct 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 62 int cond_policydb_init(struct policydb *p); 63 void cond_policydb_destroy(struct policydb *p); 64 65 int cond_init_bool_indexes(struct policydb *p); 66 int cond_destroy_bool(void *key, void *datum, void *p); 67 68 int cond_index_bool(void *key, void *datum, void *datap); 69 70 int cond_read_bool(struct policydb *p, struct hashtab *h, void *fp); 71 int cond_read_list(struct policydb *p, void *fp); 72 73 void cond_compute_av(struct avtab *ctab, struct avtab_key *key, struct av_decision *avd); 74 75 int evaluate_cond_node(struct policydb *p, struct cond_node *node); 76 77 #endif /* _CONDITIONAL_H_ */ 78