xref: /linux/security/integrity/ima/ima_mok.c (revision e9a83bd2322035ed9d7dcf35753d3f984d76c6a5)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2015 Juniper Networks, Inc.
4  *
5  * Author:
6  * Petko Manolov <petko.manolov@konsulko.com>
7  */
8 
9 #include <linux/export.h>
10 #include <linux/kernel.h>
11 #include <linux/sched.h>
12 #include <linux/cred.h>
13 #include <linux/err.h>
14 #include <linux/init.h>
15 #include <linux/slab.h>
16 #include <keys/system_keyring.h>
17 
18 
19 static struct key_acl integrity_blacklist_keyring_acl = {
20 	.usage	= REFCOUNT_INIT(1),
21 	.nr_ace	= 2,
22 	.aces = {
23 		KEY_POSSESSOR_ACE(KEY_ACE_SEARCH | KEY_ACE_WRITE),
24 		KEY_OWNER_ACE(KEY_ACE_VIEW | KEY_ACE_READ | KEY_ACE_WRITE | KEY_ACE_SEARCH),
25 	}
26 };
27 
28 struct key *ima_blacklist_keyring;
29 
30 /*
31  * Allocate the IMA blacklist keyring
32  */
33 __init int ima_mok_init(void)
34 {
35 	struct key_restriction *restriction;
36 
37 	pr_notice("Allocating IMA blacklist keyring.\n");
38 
39 	restriction = kzalloc(sizeof(struct key_restriction), GFP_KERNEL);
40 	if (!restriction)
41 		panic("Can't allocate IMA blacklist restriction.");
42 
43 	restriction->check = restrict_link_by_builtin_trusted;
44 
45 	ima_blacklist_keyring = keyring_alloc(".ima_blacklist",
46 				KUIDT_INIT(0), KGIDT_INIT(0), current_cred(),
47 			        &integrity_blacklist_keyring_acl,
48 				KEY_ALLOC_NOT_IN_QUOTA,
49 				restriction, NULL);
50 
51 	if (IS_ERR(ima_blacklist_keyring))
52 		panic("Can't allocate IMA blacklist keyring.");
53 
54 	set_bit(KEY_FLAG_KEEP, &ima_blacklist_keyring->flags);
55 	return 0;
56 }
57 device_initcall(ima_mok_init);
58