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1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Access vector cache interface for object managers.
4 *
5 * Author : Stephen Smalley, <sds@tycho.nsa.gov>
6 */
7#ifndef _SELINUX_AVC_H_
8#define _SELINUX_AVC_H_
9
10#include <linux/stddef.h>
11#include <linux/errno.h>
12#include <linux/kernel.h>
13#include <linux/kdev_t.h>
14#include <linux/spinlock.h>
15#include <linux/init.h>
16#include <linux/audit.h>
17#include <linux/lsm_audit.h>
18#include <linux/in6.h>
19#include "flask.h"
20#include "av_permissions.h"
21#include "security.h"
22
23/*
24 * An entry in the AVC.
25 */
26struct avc_entry;
27
28struct task_struct;
29struct inode;
30struct sock;
31struct sk_buff;
32
33/*
34 * AVC statistics
35 */
36struct avc_cache_stats {
37 unsigned int lookups;
38 unsigned int misses;
39 unsigned int allocations;
40 unsigned int reclaims;
41 unsigned int frees;
42};
43
44/*
45 * We only need this data after we have decided to send an audit message.
46 */
47struct selinux_audit_data {
48 u32 ssid;
49 u32 tsid;
50 u16 tclass;
51 u32 requested;
52 u32 audited;
53 u32 denied;
54 int result;
55 struct selinux_state *state;
56};
57
58/*
59 * AVC operations
60 */
61
62void __init avc_init(void);
63
64static inline u32 avc_audit_required(u32 requested,
65 struct av_decision *avd,
66 int result,
67 u32 auditdeny,
68 u32 *deniedp)
69{
70 u32 denied, audited;
71 denied = requested & ~avd->allowed;
72 if (unlikely(denied)) {
73 audited = denied & avd->auditdeny;
74 /*
75 * auditdeny is TRICKY! Setting a bit in
76 * this field means that ANY denials should NOT be audited if
77 * the policy contains an explicit dontaudit rule for that
78 * permission. Take notice that this is unrelated to the
79 * actual permissions that were denied. As an example lets
80 * assume:
81 *
82 * denied == READ
83 * avd.auditdeny & ACCESS == 0 (not set means explicit rule)
84 * auditdeny & ACCESS == 1
85 *
86 * We will NOT audit the denial even though the denied
87 * permission was READ and the auditdeny checks were for
88 * ACCESS
89 */
90 if (auditdeny && !(auditdeny & avd->auditdeny))
91 audited = 0;
92 } else if (result)
93 audited = denied = requested;
94 else
95 audited = requested & avd->auditallow;
96 *deniedp = denied;
97 return audited;
98}
99
100int slow_avc_audit(struct selinux_state *state,
101 u32 ssid, u32 tsid, u16 tclass,
102 u32 requested, u32 audited, u32 denied, int result,
103 struct common_audit_data *a,
104 unsigned flags);
105
106/**
107 * avc_audit - Audit the granting or denial of permissions.
108 * @ssid: source security identifier
109 * @tsid: target security identifier
110 * @tclass: target security class
111 * @requested: requested permissions
112 * @avd: access vector decisions
113 * @result: result from avc_has_perm_noaudit
114 * @a: auxiliary audit data
115 * @flags: VFS walk flags
116 *
117 * Audit the granting or denial of permissions in accordance
118 * with the policy. This function is typically called by
119 * avc_has_perm() after a permission check, but can also be
120 * called directly by callers who use avc_has_perm_noaudit()
121 * in order to separate the permission check from the auditing.
122 * For example, this separation is useful when the permission check must
123 * be performed under a lock, to allow the lock to be released
124 * before calling the auditing code.
125 */
126static inline int avc_audit(struct selinux_state *state,
127 u32 ssid, u32 tsid,
128 u16 tclass, u32 requested,
129 struct av_decision *avd,
130 int result,
131 struct common_audit_data *a,
132 int flags)
133{
134 u32 audited, denied;
135 audited = avc_audit_required(requested, avd, result, 0, &denied);
136 if (likely(!audited))
137 return 0;
138 return slow_avc_audit(state, ssid, tsid, tclass,
139 requested, audited, denied, result,
140 a, flags);
141}
142
143#define AVC_STRICT 1 /* Ignore permissive mode. */
144#define AVC_EXTENDED_PERMS 2 /* update extended permissions */
145int avc_has_perm_noaudit(struct selinux_state *state,
146 u32 ssid, u32 tsid,
147 u16 tclass, u32 requested,
148 unsigned flags,
149 struct av_decision *avd);
150
151int avc_has_perm(struct selinux_state *state,
152 u32 ssid, u32 tsid,
153 u16 tclass, u32 requested,
154 struct common_audit_data *auditdata);
155int avc_has_perm_flags(struct selinux_state *state,
156 u32 ssid, u32 tsid,
157 u16 tclass, u32 requested,
158 struct common_audit_data *auditdata,
159 int flags);
160
161int avc_has_extended_perms(struct selinux_state *state,
162 u32 ssid, u32 tsid, u16 tclass, u32 requested,
163 u8 driver, u8 perm, struct common_audit_data *ad);
164
165
166u32 avc_policy_seqno(struct selinux_state *state);
167
168#define AVC_CALLBACK_GRANT 1
169#define AVC_CALLBACK_TRY_REVOKE 2
170#define AVC_CALLBACK_REVOKE 4
171#define AVC_CALLBACK_RESET 8
172#define AVC_CALLBACK_AUDITALLOW_ENABLE 16
173#define AVC_CALLBACK_AUDITALLOW_DISABLE 32
174#define AVC_CALLBACK_AUDITDENY_ENABLE 64
175#define AVC_CALLBACK_AUDITDENY_DISABLE 128
176#define AVC_CALLBACK_ADD_XPERMS 256
177
178int avc_add_callback(int (*callback)(u32 event), u32 events);
179
180/* Exported to selinuxfs */
181struct selinux_avc;
182int avc_get_hash_stats(struct selinux_avc *avc, char *page);
183unsigned int avc_get_cache_threshold(struct selinux_avc *avc);
184void avc_set_cache_threshold(struct selinux_avc *avc,
185 unsigned int cache_threshold);
186
187/* Attempt to free avc node cache */
188void avc_disable(void);
189
190#ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
191DECLARE_PER_CPU(struct avc_cache_stats, avc_cache_stats);
192#endif
193
194#endif /* _SELINUX_AVC_H_ */
195
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_ */