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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Access vector cache interface for object managers.
3 *
4 * Author : Stephen Smalley, <sds@epoch.ncsc.mil>
5 */
6#ifndef _SELINUX_AVC_H_
7#define _SELINUX_AVC_H_
8
9#include <linux/stddef.h>
10#include <linux/errno.h>
11#include <linux/kernel.h>
12#include <linux/kdev_t.h>
13#include <linux/spinlock.h>
14#include <linux/init.h>
KaiGai Koheid9250de2008-08-28 16:35:57 +090015#include <linux/audit.h>
Thomas Liu2bf49692009-07-14 12:14:09 -040016#include <linux/lsm_audit.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070017#include <linux/in6.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070018#include "flask.h"
19#include "av_permissions.h"
20#include "security.h"
21
22#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
23extern int selinux_enforcing;
24#else
25#define selinux_enforcing 1
26#endif
27
28/*
29 * An entry in the AVC.
30 */
31struct avc_entry;
32
33struct task_struct;
Linus Torvalds1da177e2005-04-16 15:20:36 -070034struct inode;
35struct sock;
36struct sk_buff;
37
Linus Torvalds1da177e2005-04-16 15:20:36 -070038/*
39 * AVC statistics
40 */
Eric Parisf5269712008-05-14 11:27:45 -040041struct avc_cache_stats {
Linus Torvalds1da177e2005-04-16 15:20:36 -070042 unsigned int lookups;
Linus Torvalds1da177e2005-04-16 15:20:36 -070043 unsigned int misses;
44 unsigned int allocations;
45 unsigned int reclaims;
46 unsigned int frees;
47};
48
Eric Paris3f0882c2012-04-03 09:38:00 -070049/*
50 * We only need this data after we have decided to send an audit message.
51 */
Eric Paris899838b2012-04-04 15:01:43 -040052struct selinux_audit_data {
Eric Paris3b3b0e42012-04-03 09:37:02 -070053 u32 ssid;
54 u32 tsid;
55 u16 tclass;
56 u32 requested;
57 u32 audited;
58 u32 denied;
Eric Paris3f0882c2012-04-03 09:38:00 -070059 int result;
60};
61
62/*
Linus Torvalds1da177e2005-04-16 15:20:36 -070063 * AVC operations
64 */
65
66void __init avc_init(void);
67
Eric Paris2e334052012-04-04 15:01:42 -040068static inline u32 avc_audit_required(u32 requested,
69 struct av_decision *avd,
70 int result,
71 u32 auditdeny,
72 u32 *deniedp)
73{
74 u32 denied, audited;
75 denied = requested & ~avd->allowed;
76 if (unlikely(denied)) {
77 audited = denied & avd->auditdeny;
78 /*
79 * auditdeny is TRICKY! Setting a bit in
80 * this field means that ANY denials should NOT be audited if
81 * the policy contains an explicit dontaudit rule for that
82 * permission. Take notice that this is unrelated to the
83 * actual permissions that were denied. As an example lets
84 * assume:
85 *
86 * denied == READ
87 * avd.auditdeny & ACCESS == 0 (not set means explicit rule)
88 * auditdeny & ACCESS == 1
89 *
90 * We will NOT audit the denial even though the denied
91 * permission was READ and the auditdeny checks were for
92 * ACCESS
93 */
94 if (auditdeny && !(auditdeny & avd->auditdeny))
95 audited = 0;
96 } else if (result)
97 audited = denied = requested;
98 else
99 audited = requested & avd->auditallow;
100 *deniedp = denied;
101 return audited;
102}
103
104int slow_avc_audit(u32 ssid, u32 tsid, u16 tclass,
Stephen Smalleyca7786a2014-04-29 11:29:04 -0700105 u32 requested, u32 audited, u32 denied, int result,
Eric Paris2e334052012-04-04 15:01:42 -0400106 struct common_audit_data *a,
107 unsigned flags);
108
109/**
110 * avc_audit - Audit the granting or denial of permissions.
111 * @ssid: source security identifier
112 * @tsid: target security identifier
113 * @tclass: target security class
114 * @requested: requested permissions
115 * @avd: access vector decisions
116 * @result: result from avc_has_perm_noaudit
117 * @a: auxiliary audit data
118 * @flags: VFS walk flags
119 *
120 * Audit the granting or denial of permissions in accordance
121 * with the policy. This function is typically called by
122 * avc_has_perm() after a permission check, but can also be
123 * called directly by callers who use avc_has_perm_noaudit()
124 * in order to separate the permission check from the auditing.
125 * For example, this separation is useful when the permission check must
126 * be performed under a lock, to allow the lock to be released
127 * before calling the auditing code.
128 */
129static inline int avc_audit(u32 ssid, u32 tsid,
130 u16 tclass, u32 requested,
131 struct av_decision *avd,
132 int result,
Linus Torvaldsab354062013-10-04 14:05:38 -0700133 struct common_audit_data *a)
Eric Paris2e334052012-04-04 15:01:42 -0400134{
135 u32 audited, denied;
Eric Paris1d349292012-04-04 15:01:43 -0400136 audited = avc_audit_required(requested, avd, result, 0, &denied);
Eric Paris2e334052012-04-04 15:01:42 -0400137 if (likely(!audited))
138 return 0;
139 return slow_avc_audit(ssid, tsid, tclass,
Stephen Smalleyca7786a2014-04-29 11:29:04 -0700140 requested, audited, denied, result,
Linus Torvaldsab354062013-10-04 14:05:38 -0700141 a, 0);
Eric Paris2e334052012-04-04 15:01:42 -0400142}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700143
Stephen Smalley2c3c05d2007-06-07 15:34:10 -0400144#define AVC_STRICT 1 /* Ignore permissive mode. */
Jeff Vander Stoepfa1aa142015-07-10 17:19:56 -0400145#define AVC_EXTENDED_PERMS 2 /* update extended permissions */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146int avc_has_perm_noaudit(u32 ssid, u32 tsid,
Stephen Smalley2c3c05d2007-06-07 15:34:10 -0400147 u16 tclass, u32 requested,
148 unsigned flags,
149 struct av_decision *avd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700150
Linus Torvaldscb4fbe52013-10-04 12:57:22 -0700151int avc_has_perm(u32 ssid, u32 tsid,
152 u16 tclass, u32 requested,
153 struct common_audit_data *auditdata);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154
Jeff Vander Stoepfa1aa142015-07-10 17:19:56 -0400155int avc_has_extended_perms(u32 ssid, u32 tsid, u16 tclass, u32 requested,
156 u8 driver, u8 perm, struct common_audit_data *ad);
157
158
Yuichi Nakamura788e7dd2007-09-14 09:27:07 +0900159u32 avc_policy_seqno(void);
160
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161#define AVC_CALLBACK_GRANT 1
162#define AVC_CALLBACK_TRY_REVOKE 2
163#define AVC_CALLBACK_REVOKE 4
164#define AVC_CALLBACK_RESET 8
165#define AVC_CALLBACK_AUDITALLOW_ENABLE 16
166#define AVC_CALLBACK_AUDITALLOW_DISABLE 32
167#define AVC_CALLBACK_AUDITDENY_ENABLE 64
168#define AVC_CALLBACK_AUDITDENY_DISABLE 128
Jeff Vander Stoepfa1aa142015-07-10 17:19:56 -0400169#define AVC_CALLBACK_ADD_XPERMS 256
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170
Wanlong Gao562c99f2012-03-07 22:17:14 +0800171int avc_add_callback(int (*callback)(u32 event), u32 events);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172
Linus Torvalds1da177e2005-04-16 15:20:36 -0700173/* Exported to selinuxfs */
174int avc_get_hash_stats(char *page);
175extern unsigned int avc_cache_threshold;
176
Thomas Liu89c86572009-06-24 17:58:05 -0400177/* Attempt to free avc node cache */
178void avc_disable(void);
179
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
181DECLARE_PER_CPU(struct avc_cache_stats, avc_cache_stats);
182#endif
183
184#endif /* _SELINUX_AVC_H_ */
185