xref: /OK3568_Linux_fs/kernel/security/safesetid/lsm.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * SafeSetID Linux Security Module
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  * Author: Micah Morton <mortonm@chromium.org>
6*4882a593Smuzhiyun  *
7*4882a593Smuzhiyun  * Copyright (C) 2018 The Chromium OS Authors.
8*4882a593Smuzhiyun  *
9*4882a593Smuzhiyun  * This program is free software; you can redistribute it and/or modify
10*4882a593Smuzhiyun  * it under the terms of the GNU General Public License version 2, as
11*4882a593Smuzhiyun  * published by the Free Software Foundation.
12*4882a593Smuzhiyun  *
13*4882a593Smuzhiyun  */
14*4882a593Smuzhiyun #ifndef _SAFESETID_H
15*4882a593Smuzhiyun #define _SAFESETID_H
16*4882a593Smuzhiyun 
17*4882a593Smuzhiyun #include <linux/types.h>
18*4882a593Smuzhiyun #include <linux/uidgid.h>
19*4882a593Smuzhiyun #include <linux/hashtable.h>
20*4882a593Smuzhiyun 
21*4882a593Smuzhiyun /* Flag indicating whether initialization completed */
22*4882a593Smuzhiyun extern int safesetid_initialized;
23*4882a593Smuzhiyun 
24*4882a593Smuzhiyun enum sid_policy_type {
25*4882a593Smuzhiyun 	SIDPOL_DEFAULT, /* source ID is unaffected by policy */
26*4882a593Smuzhiyun 	SIDPOL_CONSTRAINED, /* source ID is affected by policy */
27*4882a593Smuzhiyun 	SIDPOL_ALLOWED /* target ID explicitly allowed */
28*4882a593Smuzhiyun };
29*4882a593Smuzhiyun 
30*4882a593Smuzhiyun typedef union {
31*4882a593Smuzhiyun 	kuid_t uid;
32*4882a593Smuzhiyun 	kgid_t gid;
33*4882a593Smuzhiyun } kid_t;
34*4882a593Smuzhiyun 
35*4882a593Smuzhiyun enum setid_type {
36*4882a593Smuzhiyun 	UID,
37*4882a593Smuzhiyun 	GID
38*4882a593Smuzhiyun };
39*4882a593Smuzhiyun 
40*4882a593Smuzhiyun /*
41*4882a593Smuzhiyun  * Hash table entry to store safesetid policy signifying that 'src_id'
42*4882a593Smuzhiyun  * can set*id to 'dst_id'.
43*4882a593Smuzhiyun  */
44*4882a593Smuzhiyun struct setid_rule {
45*4882a593Smuzhiyun 	struct hlist_node next;
46*4882a593Smuzhiyun 	kid_t src_id;
47*4882a593Smuzhiyun 	kid_t dst_id;
48*4882a593Smuzhiyun 
49*4882a593Smuzhiyun 	/* Flag to signal if rule is for UID's or GID's */
50*4882a593Smuzhiyun 	enum setid_type type;
51*4882a593Smuzhiyun };
52*4882a593Smuzhiyun 
53*4882a593Smuzhiyun #define SETID_HASH_BITS 8 /* 256 buckets in hash table */
54*4882a593Smuzhiyun 
55*4882a593Smuzhiyun /* Extension of INVALID_UID/INVALID_GID for kid_t type */
56*4882a593Smuzhiyun #define INVALID_ID (kid_t){.uid = INVALID_UID}
57*4882a593Smuzhiyun 
58*4882a593Smuzhiyun struct setid_ruleset {
59*4882a593Smuzhiyun 	DECLARE_HASHTABLE(rules, SETID_HASH_BITS);
60*4882a593Smuzhiyun 	char *policy_str;
61*4882a593Smuzhiyun 	struct rcu_head rcu;
62*4882a593Smuzhiyun 
63*4882a593Smuzhiyun 	//Flag to signal if ruleset is for UID's or GID's
64*4882a593Smuzhiyun 	enum setid_type type;
65*4882a593Smuzhiyun };
66*4882a593Smuzhiyun 
67*4882a593Smuzhiyun enum sid_policy_type _setid_policy_lookup(struct setid_ruleset *policy,
68*4882a593Smuzhiyun 		kid_t src, kid_t dst);
69*4882a593Smuzhiyun 
70*4882a593Smuzhiyun extern struct setid_ruleset __rcu *safesetid_setuid_rules;
71*4882a593Smuzhiyun extern struct setid_ruleset __rcu *safesetid_setgid_rules;
72*4882a593Smuzhiyun 
73*4882a593Smuzhiyun #endif /* _SAFESETID_H */
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