2 * Access vector cache interface for object managers.
4 * Author : Stephen Smalley, <sds@epoch.ncsc.mil>
6 #ifndef _SELINUX_AVC_H_
7 #define _SELINUX_AVC_H_
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>
19 #include "av_permissions.h"
22 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
23 extern int selinux_enforcing;
25 #define selinux_enforcing 1
29 * An entry in the AVC.
41 struct avc_cache_stats {
44 unsigned int allocations;
45 unsigned int reclaims;
50 * We only need this data after we have decided to send an audit message.
52 struct selinux_late_audit_data {
63 * We collect this at the beginning or during an selinux security operation
65 struct selinux_audit_data {
67 * auditdeny is a bit tricky and unintuitive. See the
68 * comments in avc.c for it's meaning and usage.
71 struct selinux_late_audit_data *slad;
78 void __init avc_init(void);
80 static inline u32 avc_audit_required(u32 requested,
81 struct av_decision *avd,
87 denied = requested & ~avd->allowed;
88 if (unlikely(denied)) {
89 audited = denied & avd->auditdeny;
91 * auditdeny is TRICKY! Setting a bit in
92 * this field means that ANY denials should NOT be audited if
93 * the policy contains an explicit dontaudit rule for that
94 * permission. Take notice that this is unrelated to the
95 * actual permissions that were denied. As an example lets
99 * avd.auditdeny & ACCESS == 0 (not set means explicit rule)
100 * auditdeny & ACCESS == 1
102 * We will NOT audit the denial even though the denied
103 * permission was READ and the auditdeny checks were for
106 if (auditdeny && !(auditdeny & avd->auditdeny))
109 audited = denied = requested;
111 audited = requested & avd->auditallow;
116 int slow_avc_audit(u32 ssid, u32 tsid, u16 tclass,
117 u32 requested, u32 audited, u32 denied,
118 struct common_audit_data *a,
122 * avc_audit - Audit the granting or denial of permissions.
123 * @ssid: source security identifier
124 * @tsid: target security identifier
125 * @tclass: target security class
126 * @requested: requested permissions
127 * @avd: access vector decisions
128 * @result: result from avc_has_perm_noaudit
129 * @a: auxiliary audit data
130 * @flags: VFS walk flags
132 * Audit the granting or denial of permissions in accordance
133 * with the policy. This function is typically called by
134 * avc_has_perm() after a permission check, but can also be
135 * called directly by callers who use avc_has_perm_noaudit()
136 * in order to separate the permission check from the auditing.
137 * For example, this separation is useful when the permission check must
138 * be performed under a lock, to allow the lock to be released
139 * before calling the auditing code.
141 static inline int avc_audit(u32 ssid, u32 tsid,
142 u16 tclass, u32 requested,
143 struct av_decision *avd,
145 struct common_audit_data *a, unsigned flags)
148 audited = avc_audit_required(requested, avd, result,
149 a ? a->selinux_audit_data->auditdeny : 0,
151 if (likely(!audited))
153 return slow_avc_audit(ssid, tsid, tclass,
154 requested, audited, denied,
158 #define AVC_STRICT 1 /* Ignore permissive mode. */
159 int avc_has_perm_noaudit(u32 ssid, u32 tsid,
160 u16 tclass, u32 requested,
162 struct av_decision *avd);
164 int avc_has_perm_flags(u32 ssid, u32 tsid,
165 u16 tclass, u32 requested,
166 struct common_audit_data *auditdata,
169 static inline int avc_has_perm(u32 ssid, u32 tsid,
170 u16 tclass, u32 requested,
171 struct common_audit_data *auditdata)
173 return avc_has_perm_flags(ssid, tsid, tclass, requested, auditdata, 0);
176 u32 avc_policy_seqno(void);
178 #define AVC_CALLBACK_GRANT 1
179 #define AVC_CALLBACK_TRY_REVOKE 2
180 #define AVC_CALLBACK_REVOKE 4
181 #define AVC_CALLBACK_RESET 8
182 #define AVC_CALLBACK_AUDITALLOW_ENABLE 16
183 #define AVC_CALLBACK_AUDITALLOW_DISABLE 32
184 #define AVC_CALLBACK_AUDITDENY_ENABLE 64
185 #define AVC_CALLBACK_AUDITDENY_DISABLE 128
187 int avc_add_callback(int (*callback)(u32 event, u32 ssid, u32 tsid,
188 u16 tclass, u32 perms,
190 u32 events, u32 ssid, u32 tsid,
191 u16 tclass, u32 perms);
193 /* Exported to selinuxfs */
194 int avc_get_hash_stats(char *page);
195 extern unsigned int avc_cache_threshold;
197 /* Attempt to free avc node cache */
198 void avc_disable(void);
200 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
201 DECLARE_PER_CPU(struct avc_cache_stats, avc_cache_stats);
204 #endif /* _SELINUX_AVC_H_ */