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1/*
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>
15#include <linux/audit.h>
16#include <linux/lsm_audit.h>
17#include <linux/in6.h>
18#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;
34struct inode;
35struct sock;
36struct sk_buff;
37
38/*
39 * AVC statistics
40 */
41struct avc_cache_stats {
42 unsigned int lookups;
43 unsigned int misses;
44 unsigned int allocations;
45 unsigned int reclaims;
46 unsigned int frees;
47};
48
49/*
50 * We only need this data after we have decided to send an audit message.
51 */
52struct selinux_audit_data {
53 u32 ssid;
54 u32 tsid;
55 u16 tclass;
56 u32 requested;
57 u32 audited;
58 u32 denied;
59 int result;
60};
61
62/*
63 * AVC operations
64 */
65
66void __init avc_init(void);
67
68static 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,
105 u32 requested, u32 audited, u32 denied, int result,
106 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,
133 struct common_audit_data *a,
134 int flags)
135{
136 u32 audited, denied;
137 audited = avc_audit_required(requested, avd, result, 0, &denied);
138 if (likely(!audited))
139 return 0;
140 return slow_avc_audit(ssid, tsid, tclass,
141 requested, audited, denied, result,
142 a, flags);
143}
144
145#define AVC_STRICT 1 /* Ignore permissive mode. */
146#define AVC_EXTENDED_PERMS 2 /* update extended permissions */
147int avc_has_perm_noaudit(u32 ssid, u32 tsid,
148 u16 tclass, u32 requested,
149 unsigned flags,
150 struct av_decision *avd);
151
152int avc_has_perm(u32 ssid, u32 tsid,
153 u16 tclass, u32 requested,
154 struct common_audit_data *auditdata);
155int avc_has_perm_flags(u32 ssid, u32 tsid,
156 u16 tclass, u32 requested,
157 struct common_audit_data *auditdata,
158 int flags);
159
160int avc_has_extended_perms(u32 ssid, u32 tsid, u16 tclass, u32 requested,
161 u8 driver, u8 perm, struct common_audit_data *ad);
162
163
164u32 avc_policy_seqno(void);
165
166#define AVC_CALLBACK_GRANT 1
167#define AVC_CALLBACK_TRY_REVOKE 2
168#define AVC_CALLBACK_REVOKE 4
169#define AVC_CALLBACK_RESET 8
170#define AVC_CALLBACK_AUDITALLOW_ENABLE 16
171#define AVC_CALLBACK_AUDITALLOW_DISABLE 32
172#define AVC_CALLBACK_AUDITDENY_ENABLE 64
173#define AVC_CALLBACK_AUDITDENY_DISABLE 128
174#define AVC_CALLBACK_ADD_XPERMS 256
175
176int avc_add_callback(int (*callback)(u32 event), u32 events);
177
178/* Exported to selinuxfs */
179int avc_get_hash_stats(char *page);
180extern unsigned int avc_cache_threshold;
181
182/* Attempt to free avc node cache */
183void avc_disable(void);
184
185#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
186DECLARE_PER_CPU(struct avc_cache_stats, avc_cache_stats);
187#endif
188
189#endif /* _SELINUX_AVC_H_ */
190
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Access vector cache interface for object managers.
4 *
5 * Author : Stephen Smalley, <stephen.smalley.work@gmail.com>
6 */
7
8#ifndef _SELINUX_AVC_H_
9#define _SELINUX_AVC_H_
10
11#include <linux/stddef.h>
12#include <linux/errno.h>
13#include <linux/kernel.h>
14#include <linux/kdev_t.h>
15#include <linux/spinlock.h>
16#include <linux/init.h>
17#include <linux/audit.h>
18#include <linux/lsm_audit.h>
19#include <linux/in6.h>
20#include "flask.h"
21#include "av_permissions.h"
22#include "security.h"
23
24/*
25 * An entry in the AVC.
26 */
27struct avc_entry;
28
29struct task_struct;
30struct inode;
31struct sock;
32struct sk_buff;
33
34/*
35 * AVC statistics
36 */
37struct avc_cache_stats {
38 unsigned int lookups;
39 unsigned int misses;
40 unsigned int allocations;
41 unsigned int reclaims;
42 unsigned int frees;
43};
44
45/*
46 * We only need this data after we have decided to send an audit message.
47 */
48struct selinux_audit_data {
49 u32 ssid;
50 u32 tsid;
51 u16 tclass;
52 u32 requested;
53 u32 audited;
54 u32 denied;
55 int result;
56} __randomize_layout;
57
58/*
59 * AVC operations
60 */
61
62void __init avc_init(void);
63
64static inline u32 avc_audit_required(u32 requested, struct av_decision *avd,
65 int result, u32 auditdeny, u32 *deniedp)
66{
67 u32 denied, audited;
68 denied = requested & ~avd->allowed;
69 if (unlikely(denied)) {
70 audited = denied & avd->auditdeny;
71 /*
72 * auditdeny is TRICKY! Setting a bit in
73 * this field means that ANY denials should NOT be audited if
74 * the policy contains an explicit dontaudit rule for that
75 * permission. Take notice that this is unrelated to the
76 * actual permissions that were denied. As an example lets
77 * assume:
78 *
79 * denied == READ
80 * avd.auditdeny & ACCESS == 0 (not set means explicit rule)
81 * auditdeny & ACCESS == 1
82 *
83 * We will NOT audit the denial even though the denied
84 * permission was READ and the auditdeny checks were for
85 * ACCESS
86 */
87 if (auditdeny && !(auditdeny & avd->auditdeny))
88 audited = 0;
89 } else if (result)
90 audited = denied = requested;
91 else
92 audited = requested & avd->auditallow;
93 *deniedp = denied;
94 return audited;
95}
96
97int slow_avc_audit(u32 ssid, u32 tsid, u16 tclass, u32 requested, u32 audited,
98 u32 denied, int result, struct common_audit_data *a);
99
100/**
101 * avc_audit - Audit the granting or denial of permissions.
102 * @ssid: source security identifier
103 * @tsid: target security identifier
104 * @tclass: target security class
105 * @requested: requested permissions
106 * @avd: access vector decisions
107 * @result: result from avc_has_perm_noaudit
108 * @a: auxiliary audit data
109 *
110 * Audit the granting or denial of permissions in accordance
111 * with the policy. This function is typically called by
112 * avc_has_perm() after a permission check, but can also be
113 * called directly by callers who use avc_has_perm_noaudit()
114 * in order to separate the permission check from the auditing.
115 * For example, this separation is useful when the permission check must
116 * be performed under a lock, to allow the lock to be released
117 * before calling the auditing code.
118 */
119static inline int avc_audit(u32 ssid, u32 tsid, u16 tclass, u32 requested,
120 struct av_decision *avd, int result,
121 struct common_audit_data *a)
122{
123 u32 audited, denied;
124 audited = avc_audit_required(requested, avd, result, 0, &denied);
125 if (likely(!audited))
126 return 0;
127 return slow_avc_audit(ssid, tsid, tclass, requested, audited, denied,
128 result, a);
129}
130
131#define AVC_STRICT 1 /* Ignore permissive mode. */
132#define AVC_EXTENDED_PERMS 2 /* update extended permissions */
133int avc_has_perm_noaudit(u32 ssid, u32 tsid, u16 tclass, u32 requested,
134 unsigned int flags, struct av_decision *avd);
135
136int avc_has_perm(u32 ssid, u32 tsid, u16 tclass, u32 requested,
137 struct common_audit_data *auditdata);
138
139int avc_has_extended_perms(u32 ssid, u32 tsid, u16 tclass, u32 requested,
140 u8 driver, u8 perm, struct common_audit_data *ad);
141
142u32 avc_policy_seqno(void);
143
144#define AVC_CALLBACK_GRANT 1
145#define AVC_CALLBACK_TRY_REVOKE 2
146#define AVC_CALLBACK_REVOKE 4
147#define AVC_CALLBACK_RESET 8
148#define AVC_CALLBACK_AUDITALLOW_ENABLE 16
149#define AVC_CALLBACK_AUDITALLOW_DISABLE 32
150#define AVC_CALLBACK_AUDITDENY_ENABLE 64
151#define AVC_CALLBACK_AUDITDENY_DISABLE 128
152#define AVC_CALLBACK_ADD_XPERMS 256
153
154int avc_add_callback(int (*callback)(u32 event), u32 events);
155
156/* Exported to selinuxfs */
157int avc_get_hash_stats(char *page);
158unsigned int avc_get_cache_threshold(void);
159void avc_set_cache_threshold(unsigned int cache_threshold);
160
161#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
162DECLARE_PER_CPU(struct avc_cache_stats, avc_cache_stats);
163#endif
164
165#endif /* _SELINUX_AVC_H_ */