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_REQUEST_CACHE
 25	bool "Enable temporary caching of the last request_key() result"
 26	depends on KEYS
 27	help
 28	  This option causes the result of the last successful request_key()
 29	  call that didn't upcall to the kernel to be cached temporarily in the
 30	  task_struct.  The cache is cleared by exit and just prior to the
 31	  resumption of userspace.
 32
 33	  This allows the key used for multiple step processes where each step
 34	  wants to request a key that is likely the same as the one requested
 35	  by the last step to save on the searching.
 36
 37	  An example of such a process is a pathwalk through a network
 38	  filesystem in which each method needs to request an authentication
 39	  key.  Pathwalk will call multiple methods for each dentry traversed
 40	  (permission, d_revalidate, lookup, getxattr, getacl, ...).
 41
 42config PERSISTENT_KEYRINGS
 43	bool "Enable register of persistent per-UID keyrings"
 44	depends on KEYS
 45	help
 46	  This option provides a register of persistent per-UID keyrings,
 47	  primarily aimed at Kerberos key storage.  The keyrings are persistent
 48	  in the sense that they stay around after all processes of that UID
 49	  have exited, not that they survive the machine being rebooted.
 50
 51	  A particular keyring may be accessed by either the user whose keyring
 52	  it is or by a process with administrative privileges.  The active
 53	  LSMs gets to rule on which admin-level processes get to access the
 54	  cache.
 55
 56	  Keyrings are created and added into the register upon demand and get
 57	  removed if they expire (a default timeout is set upon creation).
 58
 59config BIG_KEYS
 60	bool "Large payload keys"
 61	depends on KEYS
 62	depends on TMPFS
 63	depends on CRYPTO_LIB_CHACHA20POLY1305 = y
 64	help
 65	  This option provides support for holding large keys within the kernel
 66	  (for example Kerberos ticket caches).  The data may be stored out to
 67	  swapspace by tmpfs.
 68
 69	  If you are unsure as to whether this is required, answer N.
 70
 71config TRUSTED_KEYS
 72	tristate "TRUSTED KEYS"
 73	depends on KEYS
 
 
 
 
 74	help
 75	  This option provides support for creating, sealing, and unsealing
 76	  keys in the kernel. Trusted keys are random number symmetric keys,
 77	  generated and sealed by a trust source selected at kernel boot-time.
 78	  Userspace will only ever see encrypted blobs.
 
 79
 80	  If you are unsure as to whether this is required, answer N.
 81
 82if TRUSTED_KEYS
 83source "security/keys/trusted-keys/Kconfig"
 84endif
 85
 86config ENCRYPTED_KEYS
 87	tristate "ENCRYPTED KEYS"
 88	depends on KEYS
 89	select CRYPTO
 90	select CRYPTO_HMAC
 91	select CRYPTO_AES
 92	select CRYPTO_CBC
 93	select CRYPTO_SHA256
 94	select CRYPTO_RNG
 95	help
 96	  This option provides support for create/encrypting/decrypting keys
 97	  in the kernel.  Encrypted keys are instantiated using kernel
 98	  generated random numbers or provided decrypted data, and are
 99	  encrypted/decrypted with a 'master' symmetric key. The 'master'
100	  key can be either a trusted-key or user-key type. Only encrypted
101	  blobs are ever output to Userspace.
102
103	  If you are unsure as to whether this is required, answer N.
104
105config USER_DECRYPTED_DATA
106	bool "Allow encrypted keys with user decrypted data"
107	depends on ENCRYPTED_KEYS
108	help
109	  This option provides support for instantiating encrypted keys using
110	  user-provided decrypted data.  The decrypted data must be hex-ascii
111	  encoded.
112
113	  If you are unsure as to whether this is required, answer N.
114
115config KEY_DH_OPERATIONS
116       bool "Diffie-Hellman operations on retained keys"
117       depends on KEYS
118       select CRYPTO
119       select CRYPTO_KDF800108_CTR
120       select CRYPTO_DH
121       help
122	 This option provides support for calculating Diffie-Hellman
123	 public keys and shared secrets using values stored as keys
124	 in the kernel.
125
126	 If you are unsure as to whether this is required, answer N.
127
128config KEY_NOTIFICATIONS
129	bool "Provide key/keyring change notifications"
130	depends on KEYS && WATCH_QUEUE
131	help
132	  This option provides support for getting change notifications
133	  on keys and keyrings on which the caller has View permission.
134	  This makes use of pipes to handle the notification buffer and
135	  provides KEYCTL_WATCH_KEY to enable/disable watches.