1 // SPDX-License-Identifier: GPL-2.0
2
3 #include <linux/kernel.h>
4 #include <linux/sched.h>
5 #include <linux/cred.h>
6 #include <linux/err.h>
7 #include <linux/efi.h>
8 #include <linux/slab.h>
9 #include <keys/asymmetric-type.h>
10 #include <keys/system_keyring.h>
11 #include "../integrity.h"
12 #include "keyring_handler.h"
13
14 static efi_guid_t efi_cert_x509_guid __initdata = EFI_CERT_X509_GUID;
15 static efi_guid_t efi_cert_x509_sha256_guid __initdata =
16 EFI_CERT_X509_SHA256_GUID;
17 static efi_guid_t efi_cert_sha256_guid __initdata = EFI_CERT_SHA256_GUID;
18
19 /*
20 * Blacklist an X509 TBS hash.
21 */
uefi_blacklist_x509_tbs(const char * source,const void * data,size_t len)22 static __init void uefi_blacklist_x509_tbs(const char *source,
23 const void *data, size_t len)
24 {
25 mark_hash_blacklisted(data, len, BLACKLIST_HASH_X509_TBS);
26 }
27
28 /*
29 * Blacklist the hash of an executable.
30 */
uefi_blacklist_binary(const char * source,const void * data,size_t len)31 static __init void uefi_blacklist_binary(const char *source,
32 const void *data, size_t len)
33 {
34 mark_hash_blacklisted(data, len, BLACKLIST_HASH_BINARY);
35 }
36
37 /*
38 * Add an X509 cert to the revocation list.
39 */
uefi_revocation_list_x509(const char * source,const void * data,size_t len)40 static __init void uefi_revocation_list_x509(const char *source,
41 const void *data, size_t len)
42 {
43 add_key_to_revocation_list(data, len);
44 }
45
46 /*
47 * Return the appropriate handler for particular signature list types found in
48 * the UEFI db tables.
49 */
get_handler_for_db(const efi_guid_t * sig_type)50 __init efi_element_handler_t get_handler_for_db(const efi_guid_t *sig_type)
51 {
52 if (efi_guidcmp(*sig_type, efi_cert_x509_guid) == 0)
53 return add_to_platform_keyring;
54 return NULL;
55 }
56
57 /*
58 * Return the appropriate handler for particular signature list types found in
59 * the MokListRT tables.
60 */
get_handler_for_mok(const efi_guid_t * sig_type)61 __init efi_element_handler_t get_handler_for_mok(const efi_guid_t *sig_type)
62 {
63 if (efi_guidcmp(*sig_type, efi_cert_x509_guid) == 0) {
64 if (IS_ENABLED(CONFIG_INTEGRITY_MACHINE_KEYRING) &&
65 imputed_trust_enabled())
66 return add_to_machine_keyring;
67 else
68 return add_to_platform_keyring;
69 }
70 return NULL;
71 }
72
get_handler_for_ca_keys(const efi_guid_t * sig_type)73 __init efi_element_handler_t get_handler_for_ca_keys(const efi_guid_t *sig_type)
74 {
75 if (efi_guidcmp(*sig_type, efi_cert_x509_guid) == 0)
76 return add_to_machine_keyring;
77
78 return NULL;
79 }
80
get_handler_for_code_signing_keys(const efi_guid_t * sig_type)81 __init efi_element_handler_t get_handler_for_code_signing_keys(const efi_guid_t *sig_type)
82 {
83 if (efi_guidcmp(*sig_type, efi_cert_x509_guid) == 0)
84 return add_to_secondary_keyring;
85
86 return NULL;
87 }
88
89 /*
90 * Return the appropriate handler for particular signature list types found in
91 * the UEFI dbx and MokListXRT tables.
92 */
get_handler_for_dbx(const efi_guid_t * sig_type)93 __init efi_element_handler_t get_handler_for_dbx(const efi_guid_t *sig_type)
94 {
95 if (efi_guidcmp(*sig_type, efi_cert_x509_sha256_guid) == 0)
96 return uefi_blacklist_x509_tbs;
97 if (efi_guidcmp(*sig_type, efi_cert_sha256_guid) == 0)
98 return uefi_blacklist_binary;
99 if (efi_guidcmp(*sig_type, efi_cert_x509_guid) == 0)
100 return uefi_revocation_list_x509;
101 return NULL;
102 }
103