1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3 * An access vector table (avtab) is a hash table
4 * of access vectors and transition types indexed
5 * by a type pair and a class. An access vector
6 * table is used to represent the type enforcement
7 * tables.
8 *
9 * Author : Stephen Smalley, <stephen.smalley.work@gmail.com>
10 */
11
12 /* Updated: Frank Mayer <mayerf@tresys.com> and
13 * Karl MacMillan <kmacmillan@tresys.com>
14 * Added conditional policy language extensions
15 * Copyright (C) 2003 Tresys Technology, LLC
16 *
17 * Updated: Yuichi Nakamura <ynakam@hitachisoft.jp>
18 * Tuned number of hash slots for avtab to reduce memory usage
19 */
20
21 #ifndef _SS_AVTAB_H_
22 #define _SS_AVTAB_H_
23
24 #include "security.h"
25
26 struct avtab_key {
27 u16 source_type; /* source type */
28 u16 target_type; /* target type */
29 u16 target_class; /* target object class */
30 #define AVTAB_ALLOWED 0x0001
31 #define AVTAB_AUDITALLOW 0x0002
32 #define AVTAB_AUDITDENY 0x0004
33 #define AVTAB_AV (AVTAB_ALLOWED | AVTAB_AUDITALLOW | AVTAB_AUDITDENY)
34 #define AVTAB_TRANSITION 0x0010
35 #define AVTAB_MEMBER 0x0020
36 #define AVTAB_CHANGE 0x0040
37 #define AVTAB_TYPE (AVTAB_TRANSITION | AVTAB_MEMBER | AVTAB_CHANGE)
38 /* extended permissions */
39 #define AVTAB_XPERMS_ALLOWED 0x0100
40 #define AVTAB_XPERMS_AUDITALLOW 0x0200
41 #define AVTAB_XPERMS_DONTAUDIT 0x0400
42 #define AVTAB_XPERMS \
43 (AVTAB_XPERMS_ALLOWED | AVTAB_XPERMS_AUDITALLOW | \
44 AVTAB_XPERMS_DONTAUDIT)
45 #define AVTAB_ENABLED_OLD 0x80000000 /* reserved for used in cond_avtab */
46 #define AVTAB_ENABLED 0x8000 /* reserved for used in cond_avtab */
47 u16 specified; /* what field is specified */
48 };
49
50 /*
51 * For operations that require more than the 32 permissions provided by the avc
52 * extended permissions may be used to provide 256 bits of permissions.
53 */
54 struct avtab_extended_perms {
55 /* These are not flags. All 256 values may be used */
56 #define AVTAB_XPERMS_IOCTLFUNCTION 0x01
57 #define AVTAB_XPERMS_IOCTLDRIVER 0x02
58 /* extension of the avtab_key specified */
59 u8 specified; /* ioctl, netfilter, ... */
60 /*
61 * if 256 bits is not adequate as is often the case with ioctls, then
62 * multiple extended perms may be used and the driver field
63 * specifies which permissions are included.
64 */
65 u8 driver;
66 /* 256 bits of permissions */
67 struct extended_perms_data perms;
68 };
69
70 struct avtab_datum {
71 union {
72 u32 data; /* access vector or type value */
73 struct avtab_extended_perms *xperms;
74 } u;
75 };
76
77 struct avtab_node {
78 struct avtab_key key;
79 struct avtab_datum datum;
80 struct avtab_node *next;
81 };
82
83 struct avtab {
84 struct avtab_node **htable;
85 u32 nel; /* number of elements */
86 u32 nslot; /* number of hash slots */
87 u32 mask; /* mask to compute hash func */
88 };
89
90 void avtab_init(struct avtab *h);
91 int avtab_alloc(struct avtab *, u32);
92 int avtab_alloc_dup(struct avtab *new, const struct avtab *orig);
93 void avtab_destroy(struct avtab *h);
94
95 #define MAX_AVTAB_HASH_BITS 16
96 #define MAX_AVTAB_HASH_BUCKETS (1 << MAX_AVTAB_HASH_BITS)
97
98 #ifdef CONFIG_SECURITY_SELINUX_DEBUG
99 void avtab_hash_eval(struct avtab *h, const char *tag);
100 #else
101 static inline void avtab_hash_eval(struct avtab *h, const char *tag)
102 {
103 }
104 #endif
105
106 struct policydb;
107 int avtab_read_item(struct avtab *a, void *fp, struct policydb *pol,
108 int (*insert)(struct avtab *a, const struct avtab_key *k,
109 const struct avtab_datum *d, void *p),
110 void *p);
111
112 int avtab_read(struct avtab *a, void *fp, struct policydb *pol);
113 int avtab_write_item(struct policydb *p, const struct avtab_node *cur,
114 void *fp);
115 int avtab_write(struct policydb *p, struct avtab *a, void *fp);
116
117 struct avtab_node *avtab_insert_nonunique(struct avtab *h,
118 const struct avtab_key *key,
119 const struct avtab_datum *datum);
120
121 struct avtab_node *avtab_search_node(struct avtab *h,
122 const struct avtab_key *key);
123 struct avtab_node *avtab_search_node_next(struct avtab_node *node,
124 u16 specified);
125
126 #endif /* _SS_AVTAB_H_ */
127
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.