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_XPERMS_ALLOWED	0x0100
63 #define AVTAB_XPERMS_AUDITALLOW	0x0200
64 #define AVTAB_XPERMS_DONTAUDIT	0x0400
65 #define AVTAB_XPERMS_NEVERALLOW	0x0800
66 #define AVTAB_XPERMS		(AVTAB_XPERMS_ALLOWED | AVTAB_XPERMS_AUDITALLOW | AVTAB_XPERMS_DONTAUDIT)
67 #define AVTAB_ENABLED_OLD	0x80000000
68 #define AVTAB_ENABLED		0x8000	/* reserved for used in cond_avtab */
69 	uint16_t specified;	/* what fields are specified */
70 } avtab_key_t;
71 
72 typedef struct avtab_extended_perms {
73 
74 #define AVTAB_XPERMS_IOCTLFUNCTION	0x01
75 #define AVTAB_XPERMS_IOCTLDRIVER	0x02
76 	/* extension of the avtab_key specified */
77 	uint8_t specified;
78 	uint8_t driver;
79 	uint32_t perms[8];
80 } avtab_extended_perms_t;
81 
82 typedef struct avtab_datum {
83 	uint32_t data;		/* access vector or type */
84 	avtab_extended_perms_t *xperms;
85 } avtab_datum_t;
86 
87 typedef struct avtab_node *avtab_ptr_t;
88 
89 struct avtab_node {
90 	avtab_key_t key;
91 	avtab_datum_t datum;
92 	avtab_ptr_t next;
93 	void *parse_context;	/* generic context pointer used by parser;
94 				 * not saved in binary policy */
95 	unsigned merged;	/* flag for avtab_write only;
96 				   not saved in binary policy */
97 };
98 
99 typedef struct avtab {
100 	avtab_ptr_t *htable;
101 	uint32_t nel;		/* number of elements */
102 	uint32_t nslot;         /* number of hash slots */
103 	uint32_t mask;          /* mask to compute hash func */
104 } avtab_t;
105 
106 extern int avtab_init(avtab_t *);
107 extern int avtab_alloc(avtab_t *, uint32_t);
108 extern int avtab_insert(avtab_t * h, avtab_key_t * k, avtab_datum_t * d);
109 
110 extern avtab_datum_t *avtab_search(avtab_t * h, avtab_key_t * k);
111 
112 extern void avtab_destroy(avtab_t * h);
113 
114 extern int avtab_map(avtab_t * h,
115 		     int (*apply) (avtab_key_t * k,
116 				   avtab_datum_t * d, void *args), void *args);
117 
118 extern void avtab_hash_eval(avtab_t * h, char *tag);
119 
120 struct policy_file;
121 extern int avtab_read_item(struct policy_file *fp, uint32_t vers, avtab_t * a,
122 			   int (*insert) (avtab_t * a, avtab_key_t * k,
123 					  avtab_datum_t * d, void *p), void *p);
124 
125 extern int avtab_read(avtab_t * a, struct policy_file *fp, uint32_t vers);
126 
127 extern avtab_ptr_t avtab_insert_nonunique(avtab_t * h, avtab_key_t * key,
128 					  avtab_datum_t * datum);
129 
130 extern avtab_ptr_t avtab_insert_with_parse_context(avtab_t * h,
131 						   avtab_key_t * key,
132 						   avtab_datum_t * datum,
133 						   void *parse_context);
134 
135 extern avtab_ptr_t avtab_search_node(avtab_t * h, avtab_key_t * key);
136 
137 extern avtab_ptr_t avtab_search_node_next(avtab_ptr_t node, int specified);
138 
139 #define MAX_AVTAB_HASH_BITS 20
140 #define MAX_AVTAB_HASH_BUCKETS (1 << MAX_AVTAB_HASH_BITS)
141 #define MAX_AVTAB_HASH_MASK (MAX_AVTAB_HASH_BUCKETS-1)
142 /* avtab_alloc uses one bucket per 2-4 elements, so adjust to get maximum buckets */
143 #define MAX_AVTAB_SIZE (MAX_AVTAB_HASH_BUCKETS << 1)
144 
145 __END_DECLS
146 #endif				/* _AVTAB_H_ */
147 
148 /* FLASK */
149