1# SPDX-License-Identifier: GPL-2.0
2menu "Certificates for signature checking"
3
4config MODULE_SIG_KEY
5	string "File name or PKCS#11 URI of module signing key"
6	default "certs/signing_key.pem"
7	depends on MODULE_SIG || (IMA_APPRAISE_MODSIG && MODULES)
8	help
9         Provide the file name of a private key/certificate in PEM format,
10         or a PKCS#11 URI according to RFC7512. The file should contain, or
11         the URI should identify, both the certificate and its corresponding
12         private key.
13
14         If this option is unchanged from its default "certs/signing_key.pem",
15         then the kernel will automatically generate the private key and
16         certificate as described in Documentation/admin-guide/module-signing.rst
17
18choice
19	prompt "Type of module signing key to be generated"
20	default MODULE_SIG_KEY_TYPE_RSA
21	help
22	 The type of module signing key type to generate. This option
23	 does not apply if a #PKCS11 URI is used.
24
25config MODULE_SIG_KEY_TYPE_RSA
26	bool "RSA"
27	depends on MODULE_SIG || (IMA_APPRAISE_MODSIG && MODULES)
28	help
29	 Use an RSA key for module signing.
30
31config MODULE_SIG_KEY_TYPE_ECDSA
32	bool "ECDSA"
33	select CRYPTO_ECDSA
34	depends on MODULE_SIG || (IMA_APPRAISE_MODSIG && MODULES)
35	help
36	 Use an elliptic curve key (NIST P384) for module signing. Consider
37	 using a strong hash like sha256 or sha384 for hashing modules.
38
39	 Note: Remove all ECDSA signing keys, e.g. certs/signing_key.pem,
40	 when falling back to building Linux 5.14 and older kernels.
41
42endchoice
43
44config SYSTEM_TRUSTED_KEYRING
45	bool "Provide system-wide ring of trusted keys"
46	depends on KEYS
47	depends on ASYMMETRIC_KEY_TYPE
48	help
49	  Provide a system keyring to which trusted keys can be added.  Keys in
50	  the keyring are considered to be trusted.  Keys may be added at will
51	  by the kernel from compiled-in data and from hardware key stores, but
52	  userspace may only add extra keys if those keys can be verified by
53	  keys already in the keyring.
54
55	  Keys in this keyring are used by module signature checking.
56
57config SYSTEM_TRUSTED_KEYS
58	string "Additional X.509 keys for default system keyring"
59	depends on SYSTEM_TRUSTED_KEYRING
60	help
61	  If set, this option should be the filename of a PEM-formatted file
62	  containing trusted X.509 certificates to be included in the default
63	  system keyring. Any certificate used for module signing is implicitly
64	  also trusted.
65
66	  NOTE: If you previously provided keys for the system keyring in the
67	  form of DER-encoded *.x509 files in the top-level build directory,
68	  those are no longer used. You will need to set this option instead.
69
70config SYSTEM_EXTRA_CERTIFICATE
71	bool "Reserve area for inserting a certificate without recompiling"
72	depends on SYSTEM_TRUSTED_KEYRING
73	help
74	  If set, space for an extra certificate will be reserved in the kernel
75	  image. This allows introducing a trusted certificate to the default
76	  system keyring without recompiling the kernel.
77
78config SYSTEM_EXTRA_CERTIFICATE_SIZE
79	int "Number of bytes to reserve for the extra certificate"
80	depends on SYSTEM_EXTRA_CERTIFICATE
81	default 4096
82	help
83	  This is the number of bytes reserved in the kernel image for a
84	  certificate to be inserted.
85
86config SECONDARY_TRUSTED_KEYRING
87	bool "Provide a keyring to which extra trustable keys may be added"
88	depends on SYSTEM_TRUSTED_KEYRING
89	help
90	  If set, provide a keyring to which extra keys may be added, provided
91	  those keys are not blacklisted and are vouched for by a key built
92	  into the kernel or already in the secondary trusted keyring.
93
94config SYSTEM_BLACKLIST_KEYRING
95	bool "Provide system-wide ring of blacklisted keys"
96	depends on KEYS
97	help
98	  Provide a system keyring to which blacklisted keys can be added.
99	  Keys in the keyring are considered entirely untrusted.  Keys in this
100	  keyring are used by the module signature checking to reject loading
101	  of modules signed with a blacklisted key.
102
103config SYSTEM_BLACKLIST_HASH_LIST
104	string "Hashes to be preloaded into the system blacklist keyring"
105	depends on SYSTEM_BLACKLIST_KEYRING
106	help
107	  If set, this option should be the filename of a list of hashes in the
108	  form "<hash>", "<hash>", ... .  This will be included into a C
109	  wrapper to incorporate the list into the kernel.  Each <hash> should
110	  be a string of hex digits.
111
112config SYSTEM_REVOCATION_LIST
113	bool "Provide system-wide ring of revocation certificates"
114	depends on SYSTEM_BLACKLIST_KEYRING
115	depends on PKCS7_MESSAGE_PARSER=y
116	help
117	  If set, this allows revocation certificates to be stored in the
118	  blacklist keyring and implements a hook whereby a PKCS#7 message can
119	  be checked to see if it matches such a certificate.
120
121config SYSTEM_REVOCATION_KEYS
122	string "X.509 certificates to be preloaded into the system blacklist keyring"
123	depends on SYSTEM_REVOCATION_LIST
124	help
125	  If set, this option should be the filename of a PEM-formatted file
126	  containing X.509 certificates to be included in the default blacklist
127	  keyring.
128
129endmenu
130