1 menu "Certificates for signature checking"
4 string "File name or PKCS#11 URI of module signing key"
5 default "certs/signing_key.pem"
8 Provide the file name of a private key/certificate in PEM format,
9 or a PKCS#11 URI according to RFC7512. The file should contain, or
10 the URI should identify, both the certificate and its corresponding
13 If this option is unchanged from its default "certs/signing_key.pem",
14 then the kernel will automatically generate the private key and
15 certificate as described in Documentation/module-signing.txt
17 config SYSTEM_TRUSTED_KEYRING
18 bool "Provide system-wide ring of trusted keys"
20 depends on ASYMMETRIC_KEY_TYPE
22 Provide a system keyring to which trusted keys can be added. Keys in
23 the keyring are considered to be trusted. Keys may be added at will
24 by the kernel from compiled-in data and from hardware key stores, but
25 userspace may only add extra keys if those keys can be verified by
26 keys already in the keyring.
28 Keys in this keyring are used by module signature checking.
30 config SYSTEM_TRUSTED_KEYS
31 string "Additional X.509 keys for default system keyring"
32 depends on SYSTEM_TRUSTED_KEYRING
34 If set, this option should be the filename of a PEM-formatted file
35 containing trusted X.509 certificates to be included in the default
36 system keyring. Any certificate used for module signing is implicitly
39 NOTE: If you previously provided keys for the system keyring in the
40 form of DER-encoded *.x509 files in the top-level build directory,
41 those are no longer used. You will need to set this option instead.
43 config SYSTEM_EXTRA_CERTIFICATE
44 bool "Reserve area for inserting a certificate without recompiling"
45 depends on SYSTEM_TRUSTED_KEYRING
47 If set, space for an extra certificate will be reserved in the kernel
48 image. This allows introducing a trusted certificate to the default
49 system keyring without recompiling the kernel.
51 config SYSTEM_EXTRA_CERTIFICATE_SIZE
52 int "Number of bytes to reserve for the extra certificate"
53 depends on SYSTEM_EXTRA_CERTIFICATE
56 This is the number of bytes reserved in the kernel image for a
57 certificate to be inserted.
59 config SECONDARY_TRUSTED_KEYRING
60 bool "Provide a keyring to which extra trustable keys may be added"
61 depends on SYSTEM_TRUSTED_KEYRING
63 If set, provide a keyring to which extra keys may be added, provided
64 those keys are not blacklisted and are vouched for by a key built
65 into the kernel or already in the secondary trusted keyring.
67 config SYSTEM_BLACKLIST_KEYRING
68 bool "Provide system-wide ring of blacklisted keys"
71 Provide a system keyring to which blacklisted keys can be added.
72 Keys in the keyring are considered entirely untrusted. Keys in this
73 keyring are used by the module signature checking to reject loading
74 of modules signed with a blacklisted key.
76 config SYSTEM_BLACKLIST_HASH_LIST
77 string "Hashes to be preloaded into the system blacklist keyring"
78 depends on SYSTEM_BLACKLIST_KEYRING
80 If set, this option should be the filename of a list of hashes in the
81 form "<hash>", "<hash>", ... . This will be included into a C
82 wrapper to incorporate the list into the kernel. Each <hash> should
83 be a string of hex digits.
85 config EFI_SIGNATURE_LIST_PARSER
86 bool "EFI signature list parser"
88 select X509_CERTIFICATE_PARSER
90 This option provides support for parsing EFI signature lists for
91 X.509 certificates and turning them into keys.
94 bool "Load certs and blacklist from UEFI db for module checking"
95 depends on SYSTEM_BLACKLIST_KEYRING
96 depends on SECONDARY_TRUSTED_KEYRING
98 depends on EFI_SIGNATURE_LIST_PARSER
100 If the kernel is booted in secure boot mode, this option will cause
101 the kernel to load the certificates from the UEFI db and MokListRT
102 into the secondary trusted keyring. It will also load any X.509
103 SHA256 hashes in the dbx list into the blacklist.
105 The effect of this is that, if the kernel is booted in secure boot
106 mode, modules signed with UEFI-stored keys will be permitted to be
107 loaded and keys that match the blacklist will be rejected.