1 
2 /* Author : Stephen Smalley, <sds@epoch.ncsc.mil> */
3 
4 /*
5  * Updated: Yuichi Nakamura <ynakam@hitachisoft.jp>
6  * 	Tuned number of hash slots for avtab to reduce memory usage
7  */
8 
9 /* Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
10  *
11  * 	Added conditional policy language extensions
12  *
13  * Copyright (C) 2003 Tresys Technology, LLC
14  *
15  *  This library is free software; you can redistribute it and/or
16  *  modify it under the terms of the GNU Lesser General Public
17  *  License as published by the Free Software Foundation; either
18  *  version 2.1 of the License, or (at your option) any later version.
19  *
20  *  This library is distributed in the hope that it will be useful,
21  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
22  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
23  *  Lesser General Public License for more details.
24  *
25  *  You should have received a copy of the GNU Lesser General Public
26  *  License along with this library; if not, write to the Free Software
27  *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
28  */
29 
30 /* FLASK */
31 
32 /*
33  * An access vector table (avtab) is a hash table
34  * of access vectors and transition types indexed
35  * by a type pair and a class.  An access vector
36  * table is used to represent the type enforcement
37  * tables.
38  */
39 
40 #ifndef _SEPOL_POLICYDB_AVTAB_H_
41 #define _SEPOL_POLICYDB_AVTAB_H_
42 
43 #include <sys/cdefs.h>
44 #include <sys/types.h>
45 #include <stdint.h>
46 
47 __BEGIN_DECLS
48 
49 typedef struct avtab_key {
50 	uint16_t source_type;
51 	uint16_t target_type;
52 	uint16_t target_class;
53 #define AVTAB_ALLOWED		0x0001
54 #define AVTAB_AUDITALLOW	0x0002
55 #define AVTAB_AUDITDENY		0x0004
56 #define AVTAB_NEVERALLOW	0x0080
57 #define AVTAB_AV		(AVTAB_ALLOWED | AVTAB_AUDITALLOW | AVTAB_AUDITDENY)
58 #define AVTAB_TRANSITION	0x0010
59 #define AVTAB_MEMBER		0x0020
60 #define AVTAB_CHANGE		0x0040
61 #define AVTAB_TYPE		(AVTAB_TRANSITION | AVTAB_MEMBER | AVTAB_CHANGE)
62 #define AVTAB_OPNUM_ALLOWED	0x0100
63 #define AVTAB_OPNUM_AUDITALLOW	0x0200
64 #define AVTAB_OPNUM_DONTAUDIT	0x0400
65 #define AVTAB_OPNUM		(AVTAB_OPNUM_ALLOWED | AVTAB_OPNUM_AUDITALLOW | AVTAB_OPNUM_DONTAUDIT)
66 #define AVTAB_OPTYPE_ALLOWED	0x1000
67 #define AVTAB_OPTYPE_AUDITALLOW	0x2000
68 #define AVTAB_OPTYPE_DONTAUDIT	0x4000
69 #define AVTAB_OPTYPE		(AVTAB_OPTYPE_ALLOWED | AVTAB_OPTYPE_AUDITALLOW | AVTAB_OPTYPE_DONTAUDIT)
70 #define AVTAB_OP		(AVTAB_OPNUM | AVTAB_OPTYPE)
71 #define AVTAB_ENABLED_OLD	0x80000000
72 #define AVTAB_ENABLED		0x8000	/* reserved for used in cond_avtab */
73 	uint16_t specified;	/* what fields are specified */
74 } avtab_key_t;
75 
76 typedef struct avtab_operations {
77 	uint8_t type;
78 	uint32_t perms[8];
79 } avtab_operations_t;
80 
81 typedef struct avtab_datum {
82 	uint32_t data;		/* access vector or type */
83 	avtab_operations_t *ops;
84 } avtab_datum_t;
85 
86 typedef struct avtab_node *avtab_ptr_t;
87 
88 struct avtab_node {
89 	avtab_key_t key;
90 	avtab_datum_t datum;
91 	avtab_ptr_t next;
92 	void *parse_context;	/* generic context pointer used by parser;
93 				 * not saved in binary policy */
94 	unsigned merged;	/* flag for avtab_write only;
95 				   not saved in binary policy */
96 };
97 
98 typedef struct avtab {
99 	avtab_ptr_t *htable;
100 	uint32_t nel;		/* number of elements */
101 	uint32_t nslot;         /* number of hash slots */
102 	uint32_t mask;          /* mask to compute hash func */
103 } avtab_t;
104 
105 extern int avtab_init(avtab_t *);
106 extern int avtab_alloc(avtab_t *, uint32_t);
107 extern int avtab_insert(avtab_t * h, avtab_key_t * k, avtab_datum_t * d);
108 
109 extern avtab_datum_t *avtab_search(avtab_t * h, avtab_key_t * k);
110 
111 extern void avtab_destroy(avtab_t * h);
112 
113 extern int avtab_map(avtab_t * h,
114 		     int (*apply) (avtab_key_t * k,
115 				   avtab_datum_t * d, void *args), void *args);
116 
117 extern void avtab_hash_eval(avtab_t * h, char *tag);
118 
119 struct policy_file;
120 extern int avtab_read_item(struct policy_file *fp, uint32_t vers, avtab_t * a,
121 			   int (*insert) (avtab_t * a, avtab_key_t * k,
122 					  avtab_datum_t * d, void *p), void *p);
123 
124 extern int avtab_read(avtab_t * a, struct policy_file *fp, uint32_t vers);
125 
126 extern avtab_ptr_t avtab_insert_nonunique(avtab_t * h, avtab_key_t * key,
127 					  avtab_datum_t * datum);
128 
129 extern avtab_ptr_t avtab_insert_with_parse_context(avtab_t * h,
130 						   avtab_key_t * key,
131 						   avtab_datum_t * datum,
132 						   void *parse_context);
133 
134 extern avtab_ptr_t avtab_search_node(avtab_t * h, avtab_key_t * key);
135 
136 extern avtab_ptr_t avtab_search_node_next(avtab_ptr_t node, int specified);
137 
138 #define MAX_AVTAB_HASH_BITS 20
139 #define MAX_AVTAB_HASH_BUCKETS (1 << MAX_AVTAB_HASH_BITS)
140 #define MAX_AVTAB_HASH_MASK (MAX_AVTAB_HASH_BUCKETS-1)
141 /* avtab_alloc uses one bucket per 2-4 elements, so adjust to get maximum buckets */
142 #define MAX_AVTAB_SIZE (MAX_AVTAB_HASH_BUCKETS << 1)
143 
144 __END_DECLS
145 #endif				/* _AVTAB_H_ */
146 
147 /* FLASK */
148