[linux-2.6-block.git] / security / keys / Kconfig

# SPDX-License-Identifier: GPL-2.0-only
#
# Key management configuration
#

config KEYS
	bool "Enable access key retention support"
	select ASSOCIATIVE_ARRAY
	help
	  This option provides support for retaining authentication tokens and
	  access keys in the kernel.

	  It also includes provision of methods by which such keys might be
	  associated with a process so that network filesystems, encryption
	  support and the like can find them.

	  Furthermore, a special type of key is available that acts as keyring:
	  a searchable sequence of keys. Each process is equipped with access
	  to five standard keyrings: UID-specific, GID-specific, session,
	  process and thread.

	  If you are unsure as to whether this is required, answer N.

config KEYS_COMPAT
	def_bool y
	depends on COMPAT && KEYS

config PERSISTENT_KEYRINGS
	bool "Enable register of persistent per-UID keyrings"
	depends on KEYS
	help
	  This option provides a register of persistent per-UID keyrings,
	  primarily aimed at Kerberos key storage.  The keyrings are persistent
	  in the sense that they stay around after all processes of that UID
	  have exited, not that they survive the machine being rebooted.

	  A particular keyring may be accessed by either the user whose keyring
	  it is or by a process with administrative privileges.  The active
	  LSMs gets to rule on which admin-level processes get to access the
	  cache.

	  Keyrings are created and added into the register upon demand and get
	  removed if they expire (a default timeout is set upon creation).

config BIG_KEYS
	bool "Large payload keys"
	depends on KEYS
	depends on TMPFS
	select CRYPTO
	select CRYPTO_AES
	select CRYPTO_GCM
	help
	  This option provides support for holding large keys within the kernel
	  (for example Kerberos ticket caches).  The data may be stored out to
	  swapspace by tmpfs.

	  If you are unsure as to whether this is required, answer N.

config TRUSTED_KEYS
	tristate "TRUSTED KEYS"
	depends on KEYS && TCG_TPM
	select CRYPTO
	select CRYPTO_HMAC
	select CRYPTO_SHA1
	select CRYPTO_HASH_INFO
	help
	  This option provides support for creating, sealing, and unsealing
	  keys in the kernel. Trusted keys are random number symmetric keys,
	  generated and RSA-sealed by the TPM. The TPM only unseals the keys,
	  if the boot PCRs and other criteria match.  Userspace will only ever
	  see encrypted blobs.

	  If you are unsure as to whether this is required, answer N.

config ENCRYPTED_KEYS
	tristate "ENCRYPTED KEYS"
	depends on KEYS
	select CRYPTO
	select CRYPTO_HMAC
	select CRYPTO_AES
	select CRYPTO_CBC
	select CRYPTO_SHA256
	select CRYPTO_RNG
	help
	  This option provides support for create/encrypting/decrypting keys
	  in the kernel.  Encrypted keys are kernel generated random numbers,
	  which are encrypted/decrypted with a 'master' symmetric key. The
	  'master' key can be either a trusted-key or user-key type.
	  Userspace only ever sees/stores encrypted blobs.

	  If you are unsure as to whether this is required, answer N.

config KEY_DH_OPERATIONS
       bool "Diffie-Hellman operations on retained keys"
       depends on KEYS
       select CRYPTO
       select CRYPTO_HASH
       select CRYPTO_DH
       help
	 This option provides support for calculating Diffie-Hellman
	 public keys and shared secrets using values stored as keys
	 in the kernel.

	 If you are unsure as to whether this is required, answer N.
Commit	Line	Data
ec8f24b7	1	# SPDX-License-Identifier: GPL-2.0-only
f0894940 DH	2	#
	3	# Key management configuration
	4	#
	5
	6	config KEYS
	7	bool "Enable access key retention support"
b2a4df20	8	select ASSOCIATIVE_ARRAY
f0894940 DH	9	help
	10	This option provides support for retaining authentication tokens and
	11	access keys in the kernel.
	12
	13	It also includes provision of methods by which such keys might be
	14	associated with a process so that network filesystems, encryption
	15	support and the like can find them.
	16
	17	Furthermore, a special type of key is available that acts as keyring:
	18	a searchable sequence of keys. Each process is equipped with access
	19	to five standard keyrings: UID-specific, GID-specific, session,
	20	process and thread.
	21
	22	If you are unsure as to whether this is required, answer N.
	23
47b2c3ff BA	24	config KEYS_COMPAT
	25	def_bool y
	26	depends on COMPAT && KEYS
	27
f36f8c75 DH	28	config PERSISTENT_KEYRINGS
	29	bool "Enable register of persistent per-UID keyrings"
	30	depends on KEYS
	31	help
	32	This option provides a register of persistent per-UID keyrings,
	33	primarily aimed at Kerberos key storage. The keyrings are persistent
	34	in the sense that they stay around after all processes of that UID
	35	have exited, not that they survive the machine being rebooted.
	36
	37	A particular keyring may be accessed by either the user whose keyring
	38	it is or by a process with administrative privileges. The active
	39	LSMs gets to rule on which admin-level processes get to access the
	40	cache.
	41
	42	Keyrings are created and added into the register upon demand and get
	43	removed if they expire (a default timeout is set upon creation).
	44
ab3c3587	45	config BIG_KEYS
2eaf6b5d	46	bool "Large payload keys"
ab3c3587 DH	47	depends on KEYS
ab3c3587 DH	48	depends on TMPFS
3cd18d19	49	select CRYPTO
13100a72	50	select CRYPTO_AES
428490e3	51	select CRYPTO_GCM
ab3c3587 DH	52	help
	53	This option provides support for holding large keys within the kernel
	54	(for example Kerberos ticket caches). The data may be stored out to
	55	swapspace by tmpfs.
	56
	57	If you are unsure as to whether this is required, answer N.
	58
f0894940 DH	59	config TRUSTED_KEYS
	60	tristate "TRUSTED KEYS"
	61	depends on KEYS && TCG_TPM
	62	select CRYPTO
	63	select CRYPTO_HMAC
	64	select CRYPTO_SHA1
5ca4c20c	65	select CRYPTO_HASH_INFO
f0894940 DH	66	help
	67	This option provides support for creating, sealing, and unsealing
	68	keys in the kernel. Trusted keys are random number symmetric keys,
	69	generated and RSA-sealed by the TPM. The TPM only unseals the keys,
	70	if the boot PCRs and other criteria match. Userspace will only ever
	71	see encrypted blobs.
	72
	73	If you are unsure as to whether this is required, answer N.
	74
	75	config ENCRYPTED_KEYS
	76	tristate "ENCRYPTED KEYS"
	77	depends on KEYS
	78	select CRYPTO
	79	select CRYPTO_HMAC
	80	select CRYPTO_AES
	81	select CRYPTO_CBC
	82	select CRYPTO_SHA256
	83	select CRYPTO_RNG
	84	help
	85	This option provides support for create/encrypting/decrypting keys
	86	in the kernel. Encrypted keys are kernel generated random numbers,
	87	which are encrypted/decrypted with a 'master' symmetric key. The
	88	'master' key can be either a trusted-key or user-key type.
	89	Userspace only ever sees/stores encrypted blobs.
	90
	91	If you are unsure as to whether this is required, answer N.
ddbb4114 MM	92
	93	config KEY_DH_OPERATIONS
	94	bool "Diffie-Hellman operations on retained keys"
	95	depends on KEYS
4cd4ca7c	96	select CRYPTO
f1c316a3	97	select CRYPTO_HASH
7cbe0932	98	select CRYPTO_DH
ddbb4114 MM	99	help
	100	This option provides support for calculating Diffie-Hellman
	101	public keys and shared secrets using values stored as keys
	102	in the kernel.
	103
	104	If you are unsure as to whether this is required, answer N.