[mirror_ubuntu-jammy-kernel.git] / certs / Kconfig

# SPDX-License-Identifier: GPL-2.0
menu "Certificates for signature checking"

config MODULE_SIG_KEY
	string "File name or PKCS#11 URI of module signing key"
	default "certs/signing_key.pem"
	depends on MODULE_SIG || (IMA_APPRAISE_MODSIG && MODULES)
	help
         Provide the file name of a private key/certificate in PEM format,
         or a PKCS#11 URI according to RFC7512. The file should contain, or
         the URI should identify, both the certificate and its corresponding
         private key.

         If this option is unchanged from its default "certs/signing_key.pem",
         then the kernel will automatically generate the private key and
         certificate as described in Documentation/admin-guide/module-signing.rst

choice
	prompt "Type of module signing key to be generated"
	default MODULE_SIG_KEY_TYPE_RSA
	help
	 The type of module signing key type to generate. This option
	 does not apply if a #PKCS11 URI is used.

config MODULE_SIG_KEY_TYPE_RSA
	bool "RSA"
	depends on MODULE_SIG || (IMA_APPRAISE_MODSIG && MODULES)
	help
	 Use an RSA key for module signing.

config MODULE_SIG_KEY_TYPE_ECDSA
	bool "ECDSA"
	select CRYPTO_ECDSA
	depends on MODULE_SIG || (IMA_APPRAISE_MODSIG && MODULES)
	help
	 Use an elliptic curve key (NIST P384) for module signing. Consider
	 using a strong hash like sha256 or sha384 for hashing modules.

	 Note: Remove all ECDSA signing keys, e.g. certs/signing_key.pem,
	 when falling back to building Linux 5.14 and older kernels.

endchoice

config SYSTEM_TRUSTED_KEYRING
	bool "Provide system-wide ring of trusted keys"
	depends on KEYS
	depends on ASYMMETRIC_KEY_TYPE
	help
	  Provide a system keyring to which trusted keys can be added.  Keys in
	  the keyring are considered to be trusted.  Keys may be added at will
	  by the kernel from compiled-in data and from hardware key stores, but
	  userspace may only add extra keys if those keys can be verified by
	  keys already in the keyring.

	  Keys in this keyring are used by module signature checking.

config SYSTEM_TRUSTED_KEYS
	string "Additional X.509 keys for default system keyring"
	depends on SYSTEM_TRUSTED_KEYRING
	help
	  If set, this option should be the filename of a PEM-formatted file
	  containing trusted X.509 certificates to be included in the default
	  system keyring. Any certificate used for module signing is implicitly
	  also trusted.

	  NOTE: If you previously provided keys for the system keyring in the
	  form of DER-encoded *.x509 files in the top-level build directory,
	  those are no longer used. You will need to set this option instead.

config SYSTEM_EXTRA_CERTIFICATE
	bool "Reserve area for inserting a certificate without recompiling"
	depends on SYSTEM_TRUSTED_KEYRING
	help
	  If set, space for an extra certificate will be reserved in the kernel
	  image. This allows introducing a trusted certificate to the default
	  system keyring without recompiling the kernel.

config SYSTEM_EXTRA_CERTIFICATE_SIZE
	int "Number of bytes to reserve for the extra certificate"
	depends on SYSTEM_EXTRA_CERTIFICATE
	default 4096
	help
	  This is the number of bytes reserved in the kernel image for a
	  certificate to be inserted.

config SECONDARY_TRUSTED_KEYRING
	bool "Provide a keyring to which extra trustable keys may be added"
	depends on SYSTEM_TRUSTED_KEYRING
	help
	  If set, provide a keyring to which extra keys may be added, provided
	  those keys are not blacklisted and are vouched for by a key built
	  into the kernel or already in the secondary trusted keyring.

config SYSTEM_BLACKLIST_KEYRING
	bool "Provide system-wide ring of blacklisted keys"
	depends on KEYS
	help
	  Provide a system keyring to which blacklisted keys can be added.
	  Keys in the keyring are considered entirely untrusted.  Keys in this
	  keyring are used by the module signature checking to reject loading
	  of modules signed with a blacklisted key.

config SYSTEM_BLACKLIST_HASH_LIST
	string "Hashes to be preloaded into the system blacklist keyring"
	depends on SYSTEM_BLACKLIST_KEYRING
	help
	  If set, this option should be the filename of a list of hashes in the
	  form "<hash>", "<hash>", ... .  This will be included into a C
	  wrapper to incorporate the list into the kernel.  Each <hash> should
	  be a string of hex digits.

config SYSTEM_REVOCATION_LIST
	bool "Provide system-wide ring of revocation certificates"
	depends on SYSTEM_BLACKLIST_KEYRING
	depends on PKCS7_MESSAGE_PARSER=y
	help
	  If set, this allows revocation certificates to be stored in the
	  blacklist keyring and implements a hook whereby a PKCS#7 message can
	  be checked to see if it matches such a certificate.

config SYSTEM_REVOCATION_KEYS
	string "X.509 certificates to be preloaded into the system blacklist keyring"
	depends on SYSTEM_REVOCATION_LIST
	help
	  If set, this option should be the filename of a PEM-formatted file
	  containing X.509 certificates to be included in the default blacklist
	  keyring.

endmenu
Commit	Line	Data
b2441318	1	# SPDX-License-Identifier: GPL-2.0
cfc411e7 DH	2	menu "Certificates for signature checking"
	3
	4	config MODULE_SIG_KEY
	5	string "File name or PKCS#11 URI of module signing key"
	6	default "certs/signing_key.pem"
781a5739	7	depends on MODULE_SIG \|\| (IMA_APPRAISE_MODSIG && MODULES)
cfc411e7 DH	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
5fb94e9c	16	certificate as described in Documentation/admin-guide/module-signing.rst
cfc411e7	17
a4aed36e SB	18	choice
	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
	25	config 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
	31	config 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
	42	endchoice
	43
cfc411e7 DH	44	config SYSTEM_TRUSTED_KEYRING
	45	bool "Provide system-wide ring of trusted keys"
	46	depends on KEYS
99716b7c	47	depends on ASYMMETRIC_KEY_TYPE
cfc411e7 DH	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
	57	config 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
c4c36105 MK	70	config 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
	78	config 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
d3bfe841 DH	86	config 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
734114f8 DH	94	config 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
	103	config 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
56c58126 ES	112	config 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
d1f04410 ES	121	config 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
cfc411e7	129	endmenu