1#
 2# Key management configuration
 3#
 4
 5config KEYS
 6	bool "Enable access key retention support"
 7	select ASSOCIATIVE_ARRAY
 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
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
23config 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
40config BIG_KEYS
41	bool "Large payload keys"
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
51config TRUSTED_KEYS
52	tristate "TRUSTED KEYS"
53	depends on KEYS && TCG_TPM
54	select CRYPTO
55	select CRYPTO_HMAC
56	select CRYPTO_SHA1
57	select CRYPTO_HASH_INFO
58	help
59	  This option provides support for creating, sealing, and unsealing
60	  keys in the kernel. Trusted keys are random number symmetric keys,
61	  generated and RSA-sealed by the TPM. The TPM only unseals the keys,
62	  if the boot PCRs and other criteria match.  Userspace will only ever
63	  see encrypted blobs.
64
65	  If you are unsure as to whether this is required, answer N.
66
67config ENCRYPTED_KEYS
68	tristate "ENCRYPTED KEYS"
69	depends on KEYS
70	select CRYPTO
71	select CRYPTO_HMAC
72	select CRYPTO_AES
73	select CRYPTO_CBC
74	select CRYPTO_SHA256
75	select CRYPTO_RNG
76	help
77	  This option provides support for create/encrypting/decrypting keys
78	  in the kernel.  Encrypted keys are kernel generated random numbers,
79	  which are encrypted/decrypted with a 'master' symmetric key. The
80	  'master' key can be either a trusted-key or user-key type.
81	  Userspace only ever sees/stores encrypted blobs.
82
83	  If you are unsure as to whether this is required, answer N.

  1# SPDX-License-Identifier: GPL-2.0-only
  2#
  3# Key management configuration
  4#
  5
  6config KEYS
  7	bool "Enable access key retention support"
  8	select ASSOCIATIVE_ARRAY
  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
 24config KEYS_COMPAT
 25	def_bool y
 26	depends on COMPAT && KEYS
 27
 28config KEYS_REQUEST_CACHE
 29	bool "Enable temporary caching of the last request_key() result"
 30	depends on KEYS
 31	help
 32	  This option causes the result of the last successful request_key()
 33	  call that didn't upcall to the kernel to be cached temporarily in the
 34	  task_struct.  The cache is cleared by exit and just prior to the
 35	  resumption of userspace.
 36
 37	  This allows the key used for multiple step processes where each step
 38	  wants to request a key that is likely the same as the one requested
 39	  by the last step to save on the searching.
 40
 41	  An example of such a process is a pathwalk through a network
 42	  filesystem in which each method needs to request an authentication
 43	  key.  Pathwalk will call multiple methods for each dentry traversed
 44	  (permission, d_revalidate, lookup, getxattr, getacl, ...).
 45
 46config PERSISTENT_KEYRINGS
 47	bool "Enable register of persistent per-UID keyrings"
 48	depends on KEYS
 49	help
 50	  This option provides a register of persistent per-UID keyrings,
 51	  primarily aimed at Kerberos key storage.  The keyrings are persistent
 52	  in the sense that they stay around after all processes of that UID
 53	  have exited, not that they survive the machine being rebooted.
 54
 55	  A particular keyring may be accessed by either the user whose keyring
 56	  it is or by a process with administrative privileges.  The active
 57	  LSMs gets to rule on which admin-level processes get to access the
 58	  cache.
 59
 60	  Keyrings are created and added into the register upon demand and get
 61	  removed if they expire (a default timeout is set upon creation).
 62
 63config BIG_KEYS
 64	bool "Large payload keys"
 65	depends on KEYS
 66	depends on TMPFS
 67	select CRYPTO
 68	select CRYPTO_AES
 69	select CRYPTO_GCM
 70	help
 71	  This option provides support for holding large keys within the kernel
 72	  (for example Kerberos ticket caches).  The data may be stored out to
 73	  swapspace by tmpfs.
 74
 75	  If you are unsure as to whether this is required, answer N.
 76
 77config TRUSTED_KEYS
 78	tristate "TRUSTED KEYS"
 79	depends on KEYS && TCG_TPM
 80	select CRYPTO
 81	select CRYPTO_HMAC
 82	select CRYPTO_SHA1
 83	select CRYPTO_HASH_INFO
 84	help
 85	  This option provides support for creating, sealing, and unsealing
 86	  keys in the kernel. Trusted keys are random number symmetric keys,
 87	  generated and RSA-sealed by the TPM. The TPM only unseals the keys,
 88	  if the boot PCRs and other criteria match.  Userspace will only ever
 89	  see encrypted blobs.
 90
 91	  If you are unsure as to whether this is required, answer N.
 92
 93config ENCRYPTED_KEYS
 94	tristate "ENCRYPTED KEYS"
 95	depends on KEYS
 96	select CRYPTO
 97	select CRYPTO_HMAC
 98	select CRYPTO_AES
 99	select CRYPTO_CBC
100	select CRYPTO_SHA256
101	select CRYPTO_RNG
102	help
103	  This option provides support for create/encrypting/decrypting keys
104	  in the kernel.  Encrypted keys are kernel generated random numbers,
105	  which are encrypted/decrypted with a 'master' symmetric key. The
106	  'master' key can be either a trusted-key or user-key type.
107	  Userspace only ever sees/stores encrypted blobs.
108
109	  If you are unsure as to whether this is required, answer N.
110
111config KEY_DH_OPERATIONS
112       bool "Diffie-Hellman operations on retained keys"
113       depends on KEYS
114       select CRYPTO
115       select CRYPTO_HASH
116       select CRYPTO_DH
117       help
118	 This option provides support for calculating Diffie-Hellman
119	 public keys and shared secrets using values stored as keys
120	 in the kernel.
121
122	 If you are unsure as to whether this is required, answer N.