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
26struct 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 */
54struct 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#define AVTAB_XPERMS_NLMSG 0x03
59 /* extension of the avtab_key specified */
60 u8 specified; /* ioctl, netfilter, ... */
61 /*
62 * if 256 bits is not adequate as is often the case with ioctls, then
63 * multiple extended perms may be used and the driver field
64 * specifies which permissions are included.
65 */
66 u8 driver;
67 /* 256 bits of permissions */
68 struct extended_perms_data perms;
69};
70
71struct avtab_datum {
72 union {
73 u32 data; /* access vector or type value */
74 struct avtab_extended_perms *xperms;
75 } u;
76};
77
78struct avtab_node {
79 struct avtab_key key;
80 struct avtab_datum datum;
81 struct avtab_node *next;
82};
83
84struct avtab {
85 struct avtab_node **htable;
86 u32 nel; /* number of elements */
87 u32 nslot; /* number of hash slots */
88 u32 mask; /* mask to compute hash func */
89};
90
91void avtab_init(struct avtab *h);
92int avtab_alloc(struct avtab *h, u32 nrules);
93int avtab_alloc_dup(struct avtab *new, const struct avtab *orig);
94void avtab_destroy(struct avtab *h);
95
96#define MAX_AVTAB_HASH_BITS 16
97#define MAX_AVTAB_HASH_BUCKETS (1 << MAX_AVTAB_HASH_BITS)
98
99#ifdef CONFIG_SECURITY_SELINUX_DEBUG
100void avtab_hash_eval(struct avtab *h, const char *tag);
101#else
102static inline void avtab_hash_eval(struct avtab *h, const char *tag)
103{
104}
105#endif
106
107struct policydb;
108struct policy_file;
109int avtab_read_item(struct avtab *a, struct policy_file *fp, struct policydb *pol,
110 int (*insert)(struct avtab *a, const struct avtab_key *k,
111 const struct avtab_datum *d, void *p),
112 void *p, bool conditional);
113
114int avtab_read(struct avtab *a, struct policy_file *fp, struct policydb *pol);
115int avtab_write_item(struct policydb *p, const struct avtab_node *cur,
116 struct policy_file *fp);
117int avtab_write(struct policydb *p, struct avtab *a, struct policy_file *fp);
118
119struct avtab_node *avtab_insert_nonunique(struct avtab *h,
120 const struct avtab_key *key,
121 const struct avtab_datum *datum);
122
123struct avtab_node *avtab_search_node(struct avtab *h,
124 const struct avtab_key *key);
125struct avtab_node *avtab_search_node_next(struct avtab_node *node,
126 u16 specified);
127
128#endif /* _SS_AVTAB_H_ */
129