[deliverable/linux.git] / security / keys / Kconfig

#
# 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 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
	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
	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 KEYS_DEBUG_PROC_KEYS
	bool "Enable the /proc/keys file by which keys may be viewed"
	depends on KEYS
	help
	  This option turns on support for the /proc/keys file - through which
	  can be listed all the keys on the system that are viewable by the
	  reading process.

	  The only keys included in the list are those that grant View
	  permission to the reading process whether or not it possesses them.
	  Note that LSM security checks are still performed, and may further
	  filter out keys that the current process is not authorised to view.

	  Only key attributes are listed here; key payloads are not included in
	  the resulting table.

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