xref: /linux/certs/Kconfig (revision 5fb94e9ca333f0fe1d96de06704a79942b3832c3)

# 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
	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

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.

endmenu