Greg Kroah-Hartman | b244131 | 2017-11-01 15:07:57 +0100 | [diff] [blame] | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2 | /* |
| 3 | * Access vector cache interface for object managers. |
| 4 | * |
Stephen Smalley | 7efbb60 | 2017-08-17 13:32:36 -0400 | [diff] [blame] | 5 | * Author : Stephen Smalley, <sds@tycho.nsa.gov> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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> |
KaiGai Kohei | d9250de | 2008-08-28 16:35:57 +0900 | [diff] [blame] | 16 | #include <linux/audit.h> |
Thomas Liu | 2bf4969 | 2009-07-14 12:14:09 -0400 | [diff] [blame] | 17 | #include <linux/lsm_audit.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 18 | #include <linux/in6.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 19 | #include "flask.h" |
| 20 | #include "av_permissions.h" |
| 21 | #include "security.h" |
| 22 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | /* |
| 24 | * An entry in the AVC. |
| 25 | */ |
| 26 | struct avc_entry; |
| 27 | |
| 28 | struct task_struct; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 29 | struct inode; |
| 30 | struct sock; |
| 31 | struct sk_buff; |
| 32 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 33 | /* |
| 34 | * AVC statistics |
| 35 | */ |
Eric Paris | f526971 | 2008-05-14 11:27:45 -0400 | [diff] [blame] | 36 | struct avc_cache_stats { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 37 | unsigned int lookups; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 38 | unsigned int misses; |
| 39 | unsigned int allocations; |
| 40 | unsigned int reclaims; |
| 41 | unsigned int frees; |
| 42 | }; |
| 43 | |
Eric Paris | 3f0882c | 2012-04-03 09:38:00 -0700 | [diff] [blame] | 44 | /* |
| 45 | * We only need this data after we have decided to send an audit message. |
| 46 | */ |
Eric Paris | 899838b | 2012-04-04 15:01:43 -0400 | [diff] [blame] | 47 | struct selinux_audit_data { |
Eric Paris | 3b3b0e4 | 2012-04-03 09:37:02 -0700 | [diff] [blame] | 48 | u32 ssid; |
| 49 | u32 tsid; |
| 50 | u16 tclass; |
| 51 | u32 requested; |
| 52 | u32 audited; |
| 53 | u32 denied; |
Eric Paris | 3f0882c | 2012-04-03 09:38:00 -0700 | [diff] [blame] | 54 | int result; |
Stephen Smalley | 6b6bc62 | 2018-03-05 11:47:56 -0500 | [diff] [blame] | 55 | struct selinux_state *state; |
Eric Paris | 3f0882c | 2012-04-03 09:38:00 -0700 | [diff] [blame] | 56 | }; |
| 57 | |
| 58 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 59 | * AVC operations |
| 60 | */ |
| 61 | |
| 62 | void __init avc_init(void); |
| 63 | |
Eric Paris | 2e334057 | 2012-04-04 15:01:42 -0400 | [diff] [blame] | 64 | static 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 | |
Stephen Smalley | 6b6bc62 | 2018-03-05 11:47:56 -0500 | [diff] [blame] | 100 | int slow_avc_audit(struct selinux_state *state, |
| 101 | u32 ssid, u32 tsid, u16 tclass, |
Stephen Smalley | ca7786a | 2014-04-29 11:29:04 -0700 | [diff] [blame] | 102 | u32 requested, u32 audited, u32 denied, int result, |
Stephen Smalley | 0188d5c | 2019-11-22 12:22:45 -0500 | [diff] [blame] | 103 | struct common_audit_data *a); |
Eric Paris | 2e334057 | 2012-04-04 15:01:42 -0400 | [diff] [blame] | 104 | |
| 105 | /** |
| 106 | * avc_audit - Audit the granting or denial of permissions. |
| 107 | * @ssid: source security identifier |
| 108 | * @tsid: target security identifier |
| 109 | * @tclass: target security class |
| 110 | * @requested: requested permissions |
| 111 | * @avd: access vector decisions |
| 112 | * @result: result from avc_has_perm_noaudit |
| 113 | * @a: auxiliary audit data |
| 114 | * @flags: VFS walk flags |
| 115 | * |
| 116 | * Audit the granting or denial of permissions in accordance |
| 117 | * with the policy. This function is typically called by |
| 118 | * avc_has_perm() after a permission check, but can also be |
| 119 | * called directly by callers who use avc_has_perm_noaudit() |
| 120 | * in order to separate the permission check from the auditing. |
| 121 | * For example, this separation is useful when the permission check must |
| 122 | * be performed under a lock, to allow the lock to be released |
| 123 | * before calling the auditing code. |
| 124 | */ |
Stephen Smalley | 6b6bc62 | 2018-03-05 11:47:56 -0500 | [diff] [blame] | 125 | static inline int avc_audit(struct selinux_state *state, |
| 126 | u32 ssid, u32 tsid, |
Eric Paris | 2e334057 | 2012-04-04 15:01:42 -0400 | [diff] [blame] | 127 | u16 tclass, u32 requested, |
| 128 | struct av_decision *avd, |
| 129 | int result, |
NeilBrown | 7b20ea2 | 2015-03-23 13:37:39 +1100 | [diff] [blame] | 130 | struct common_audit_data *a, |
| 131 | int flags) |
Eric Paris | 2e334057 | 2012-04-04 15:01:42 -0400 | [diff] [blame] | 132 | { |
| 133 | u32 audited, denied; |
Eric Paris | 1d34929 | 2012-04-04 15:01:43 -0400 | [diff] [blame] | 134 | audited = avc_audit_required(requested, avd, result, 0, &denied); |
Eric Paris | 2e334057 | 2012-04-04 15:01:42 -0400 | [diff] [blame] | 135 | if (likely(!audited)) |
| 136 | return 0; |
Stephen Smalley | 0188d5c | 2019-11-22 12:22:45 -0500 | [diff] [blame] | 137 | /* fall back to ref-walk if we have to generate audit */ |
| 138 | if (flags & MAY_NOT_BLOCK) |
| 139 | return -ECHILD; |
Stephen Smalley | 6b6bc62 | 2018-03-05 11:47:56 -0500 | [diff] [blame] | 140 | return slow_avc_audit(state, ssid, tsid, tclass, |
Stephen Smalley | ca7786a | 2014-04-29 11:29:04 -0700 | [diff] [blame] | 141 | requested, audited, denied, result, |
Stephen Smalley | 0188d5c | 2019-11-22 12:22:45 -0500 | [diff] [blame] | 142 | a); |
Eric Paris | 2e334057 | 2012-04-04 15:01:42 -0400 | [diff] [blame] | 143 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 144 | |
Stephen Smalley | 2c3c05d | 2007-06-07 15:34:10 -0400 | [diff] [blame] | 145 | #define AVC_STRICT 1 /* Ignore permissive mode. */ |
Jeff Vander Stoep | fa1aa14 | 2015-07-10 17:19:56 -0400 | [diff] [blame] | 146 | #define AVC_EXTENDED_PERMS 2 /* update extended permissions */ |
Stephen Smalley | 3a28cff | 2018-12-12 10:10:55 -0500 | [diff] [blame] | 147 | #define AVC_NONBLOCKING 4 /* non blocking */ |
Stephen Smalley | 6b6bc62 | 2018-03-05 11:47:56 -0500 | [diff] [blame] | 148 | int avc_has_perm_noaudit(struct selinux_state *state, |
| 149 | u32 ssid, u32 tsid, |
Stephen Smalley | 2c3c05d | 2007-06-07 15:34:10 -0400 | [diff] [blame] | 150 | u16 tclass, u32 requested, |
| 151 | unsigned flags, |
| 152 | struct av_decision *avd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 153 | |
Stephen Smalley | 6b6bc62 | 2018-03-05 11:47:56 -0500 | [diff] [blame] | 154 | int avc_has_perm(struct selinux_state *state, |
| 155 | u32 ssid, u32 tsid, |
Linus Torvalds | cb4fbe5 | 2013-10-04 12:57:22 -0700 | [diff] [blame] | 156 | u16 tclass, u32 requested, |
| 157 | struct common_audit_data *auditdata); |
Stephen Smalley | 1a37079 | 2019-11-22 12:22:44 -0500 | [diff] [blame] | 158 | int avc_has_perm_flags(struct selinux_state *state, |
| 159 | u32 ssid, u32 tsid, |
| 160 | u16 tclass, u32 requested, |
| 161 | struct common_audit_data *auditdata, |
| 162 | int flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 163 | |
Stephen Smalley | 6b6bc62 | 2018-03-05 11:47:56 -0500 | [diff] [blame] | 164 | int avc_has_extended_perms(struct selinux_state *state, |
| 165 | u32 ssid, u32 tsid, u16 tclass, u32 requested, |
| 166 | u8 driver, u8 perm, struct common_audit_data *ad); |
Jeff Vander Stoep | fa1aa14 | 2015-07-10 17:19:56 -0400 | [diff] [blame] | 167 | |
| 168 | |
Stephen Smalley | 6b6bc62 | 2018-03-05 11:47:56 -0500 | [diff] [blame] | 169 | u32 avc_policy_seqno(struct selinux_state *state); |
Yuichi Nakamura | 788e7dd | 2007-09-14 09:27:07 +0900 | [diff] [blame] | 170 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 171 | #define AVC_CALLBACK_GRANT 1 |
| 172 | #define AVC_CALLBACK_TRY_REVOKE 2 |
| 173 | #define AVC_CALLBACK_REVOKE 4 |
| 174 | #define AVC_CALLBACK_RESET 8 |
| 175 | #define AVC_CALLBACK_AUDITALLOW_ENABLE 16 |
| 176 | #define AVC_CALLBACK_AUDITALLOW_DISABLE 32 |
| 177 | #define AVC_CALLBACK_AUDITDENY_ENABLE 64 |
| 178 | #define AVC_CALLBACK_AUDITDENY_DISABLE 128 |
Jeff Vander Stoep | fa1aa14 | 2015-07-10 17:19:56 -0400 | [diff] [blame] | 179 | #define AVC_CALLBACK_ADD_XPERMS 256 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 180 | |
Wanlong Gao | 562c99f | 2012-03-07 22:17:14 +0800 | [diff] [blame] | 181 | int avc_add_callback(int (*callback)(u32 event), u32 events); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 182 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 183 | /* Exported to selinuxfs */ |
Stephen Smalley | 6b6bc62 | 2018-03-05 11:47:56 -0500 | [diff] [blame] | 184 | struct selinux_avc; |
| 185 | int avc_get_hash_stats(struct selinux_avc *avc, char *page); |
| 186 | unsigned int avc_get_cache_threshold(struct selinux_avc *avc); |
| 187 | void avc_set_cache_threshold(struct selinux_avc *avc, |
| 188 | unsigned int cache_threshold); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 189 | |
Thomas Liu | 89c8657 | 2009-06-24 17:58:05 -0400 | [diff] [blame] | 190 | /* Attempt to free avc node cache */ |
| 191 | void avc_disable(void); |
| 192 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 193 | #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS |
| 194 | DECLARE_PER_CPU(struct avc_cache_stats, avc_cache_stats); |
| 195 | #endif |
| 196 | |
| 197 | #endif /* _SELINUX_AVC_H_ */ |
| 198 | |