xref: /linux/security/integrity/platform_certs/platform_keyring.c (revision ed63b9c873601ca113da5c7b1745e3946493e9f3)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Platform keyring for firmware/platform keys
4  *
5  * Copyright IBM Corporation, 2018
6  * Author(s): Nayna Jain <nayna@linux.ibm.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/slab.h>
15 #include "../integrity.h"
16 
17 static struct key_acl platform_key_acl = {
18 	.usage	= REFCOUNT_INIT(1),
19 	.nr_ace	= 2,
20 	.aces = {
21 		KEY_POSSESSOR_ACE(KEY_ACE_SEARCH | KEY_ACE_READ),
22 		KEY_OWNER_ACE(KEY_ACE_VIEW),
23 	}
24 };
25 
26 /**
27  * add_to_platform_keyring - Add to platform keyring without validation.
28  * @source: Source of key
29  * @data: The blob holding the key
30  * @len: The length of the data blob
31  *
32  * Add a key to the platform keyring without checking its trust chain.  This
33  * is available only during kernel initialisation.
34  */
35 void __init add_to_platform_keyring(const char *source, const void *data,
36 				    size_t len)
37 {
38 	int rc;
39 
40 	rc = integrity_load_cert(INTEGRITY_KEYRING_PLATFORM, source, data, len,
41 				 &platform_key_acl);
42 	if (rc)
43 		pr_info("Error adding keys to platform keyring %s\n", source);
44 }
45 
46 /*
47  * Create the trusted keyrings.
48  */
49 static __init int platform_keyring_init(void)
50 {
51 	int rc;
52 
53 	rc = integrity_init_keyring(INTEGRITY_KEYRING_PLATFORM);
54 	if (rc)
55 		return rc;
56 
57 	pr_notice("Platform Keyring initialized\n");
58 	return 0;
59 }
60 
61 /*
62  * Must be initialised before we try and load the keys into the keyring.
63  */
64 device_initcall(platform_keyring_init);
65