Edit File: conditional.h
/* Authors: Karl MacMillan <kmacmillan@tresys.com> * Frank Mayer <mayerf@tresys.com> * * Copyright (C) 2003 - 2005 Tresys Technology, LLC * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef _SEPOL_POLICYDB_CONDITIONAL_H_ #define _SEPOL_POLICYDB_CONDITIONAL_H_ #include <sepol/policydb/flask_types.h> #include <sepol/policydb/avtab.h> #include <sepol/policydb/symtab.h> #include <sepol/policydb/policydb.h> #include <sys/cdefs.h> __BEGIN_DECLS #define COND_EXPR_MAXDEPTH 10 /* this is the max unique bools in a conditional expression * for which we precompute all outcomes for the expression. * * NOTE - do _NOT_ use value greater than 5 because * cond_node_t->expr_pre_comp can only hold at most 32 values */ #define COND_MAX_BOOLS 5 /* * A conditional expression is a list of operators and operands * in reverse polish notation. */ typedef struct cond_expr { #define COND_BOOL 1 /* plain bool */ #define COND_NOT 2 /* !bool */ #define COND_OR 3 /* bool || bool */ #define COND_AND 4 /* bool && bool */ #define COND_XOR 5 /* bool ^ bool */ #define COND_EQ 6 /* bool == bool */ #define COND_NEQ 7 /* bool != bool */ #define COND_LAST COND_NEQ uint32_t expr_type; uint32_t bool; struct cond_expr *next; } cond_expr_t; /* * Each cond_node_t contains a list of rules to be enabled/disabled * depending on the current value of the conditional expression. This * struct is for that list. */ typedef struct cond_av_list { avtab_ptr_t node; struct cond_av_list *next; } cond_av_list_t; /* * A cond node represents a conditional block in a policy. It * contains a conditional expression, the current state of the expression, * two lists of rules to enable/disable depending on the value of the * expression (the true list corresponds to if and the false list corresponds * to else).. */ typedef struct cond_node { int cur_state; cond_expr_t *expr; /* these true/false lists point into te_avtab when that is used */ cond_av_list_t *true_list; cond_av_list_t *false_list; /* and these are used during parsing and for modules */ avrule_t *avtrue_list; avrule_t *avfalse_list; /* these fields are not written to binary policy */ unsigned int nbools; uint32_t bool_ids[COND_MAX_BOOLS]; uint32_t expr_pre_comp; struct cond_node *next; /* a tunable conditional, calculated and used at expansion */ #define COND_NODE_FLAGS_TUNABLE 0x01 uint32_t flags; } cond_node_t; extern int cond_evaluate_expr(policydb_t * p, cond_expr_t * expr); extern cond_expr_t *cond_copy_expr(cond_expr_t * expr); extern int cond_expr_equal(cond_node_t * a, cond_node_t * b); extern int cond_normalize_expr(policydb_t * p, cond_node_t * cn); extern void cond_node_destroy(cond_node_t * node); extern void cond_expr_destroy(cond_expr_t * expr); extern cond_node_t *cond_node_find(policydb_t * p, cond_node_t * needle, cond_node_t * haystack, int *was_created); extern cond_node_t *cond_node_create(policydb_t * p, cond_node_t * node); extern cond_node_t *cond_node_search(policydb_t * p, cond_node_t * list, cond_node_t * cn); extern int evaluate_conds(policydb_t * p); extern avtab_datum_t *cond_av_list_search(avtab_key_t * key, cond_av_list_t * cond_list); extern void cond_av_list_destroy(cond_av_list_t * list); extern void cond_optimize_lists(cond_list_t * cl); extern int cond_policydb_init(policydb_t * p); extern void cond_policydb_destroy(policydb_t * p); extern void cond_list_destroy(cond_list_t * list); extern int cond_init_bool_indexes(policydb_t * p); extern int cond_destroy_bool(hashtab_key_t key, hashtab_datum_t datum, void *p); extern int cond_index_bool(hashtab_key_t key, hashtab_datum_t datum, void *datap); extern int cond_read_bool(policydb_t * p, hashtab_t h, struct policy_file *fp); extern int cond_read_list(policydb_t * p, cond_list_t ** list, void *fp); extern void cond_compute_av(avtab_t * ctab, avtab_key_t * key, struct sepol_av_decision *avd); __END_DECLS #endif /* _CONDITIONAL_H_ */