xref: /linux/crypto/asymmetric_keys/x509_loader.c (revision 4b132aacb0768ac1e652cf517097ea6f237214b9)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 
3 #include <linux/kernel.h>
4 #include <linux/key.h>
5 #include <keys/asymmetric-type.h>
6 
7 int x509_load_certificate_list(const u8 cert_list[],
8 			       const unsigned long list_size,
9 			       const struct key *keyring)
10 {
11 	key_ref_t key;
12 	const u8 *p, *end;
13 	size_t plen;
14 
15 	p = cert_list;
16 	end = p + list_size;
17 	while (p < end) {
18 		/* Each cert begins with an ASN.1 SEQUENCE tag and must be more
19 		 * than 256 bytes in size.
20 		 */
21 		if (end - p < 4)
22 			goto dodgy_cert;
23 		if (p[0] != 0x30 &&
24 		    p[1] != 0x82)
25 			goto dodgy_cert;
26 		plen = (p[2] << 8) | p[3];
27 		plen += 4;
28 		if (plen > end - p)
29 			goto dodgy_cert;
30 
31 		key = key_create_or_update(make_key_ref(keyring, 1),
32 					   "asymmetric",
33 					   NULL,
34 					   p,
35 					   plen,
36 					   ((KEY_POS_ALL & ~KEY_POS_SETATTR) |
37 					   KEY_USR_VIEW | KEY_USR_READ),
38 					   KEY_ALLOC_NOT_IN_QUOTA |
39 					   KEY_ALLOC_BUILT_IN |
40 					   KEY_ALLOC_BYPASS_RESTRICTION);
41 		if (IS_ERR(key)) {
42 			pr_err("Problem loading in-kernel X.509 certificate (%ld)\n",
43 			       PTR_ERR(key));
44 		} else {
45 			pr_notice("Loaded X.509 cert '%s'\n",
46 				  key_ref_to_ptr(key)->description);
47 			key_ref_put(key);
48 		}
49 		p += plen;
50 	}
51 
52 	return 0;
53 
54 dodgy_cert:
55 	pr_err("Problem parsing in-kernel X.509 certificate list\n");
56 	return 0;
57 }
58 EXPORT_SYMBOL_GPL(x509_load_certificate_list);
59