security/keys/Kconfig

   1 #
   2 # Key management configuration
   3 #
   4
   5 config 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
  23 config KEYS_COMPAT
  24         def_bool y
  25         depends on COMPAT && KEYS
  26
  27 config PERSISTENT_KEYRINGS
  28         bool "Enable register of persistent per-UID keyrings"
  29         depends on KEYS
  30         help
  31           This option provides a register of persistent per-UID keyrings,
  32           primarily aimed at Kerberos key storage.  The keyrings are persistent
  33           in the sense that they stay around after all processes of that UID
  34           have exited, not that they survive the machine being rebooted.
  35
  36           A particular keyring may be accessed by either the user whose keyring
  37           it is or by a process with administrative privileges.  The active
  38           LSMs gets to rule on which admin-level processes get to access the
  39           cache.
  40
  41           Keyrings are created and added into the register upon demand and get
  42           removed if they expire (a default timeout is set upon creation).
  43
  44 config BIG_KEYS
  45         bool "Large payload keys"
  46         depends on KEYS
  47         depends on TMPFS
  48         select CRYPTO
  49         select CRYPTO_AES
  50         select CRYPTO_GCM
  51         help
  52           This option provides support for holding large keys within the kernel
  53           (for example Kerberos ticket caches).  The data may be stored out to
  54           swapspace by tmpfs.
  55
  56           If you are unsure as to whether this is required, answer N.
  57
  58 config TRUSTED_KEYS
  59         tristate "TRUSTED KEYS"
  60         depends on KEYS && TCG_TPM
  61         select CRYPTO
  62         select CRYPTO_HMAC
  63         select CRYPTO_SHA1
  64         select CRYPTO_HASH_INFO
  65         help
  66           This option provides support for creating, sealing, and unsealing
  67           keys in the kernel. Trusted keys are random number symmetric keys,
  68           generated and RSA-sealed by the TPM. The TPM only unseals the keys,
  69           if the boot PCRs and other criteria match.  Userspace will only ever
  70           see encrypted blobs.
  71
  72           If you are unsure as to whether this is required, answer N.
  73
  74 config ENCRYPTED_KEYS
  75         tristate "ENCRYPTED KEYS"
  76         depends on KEYS
  77         select CRYPTO
  78         select CRYPTO_HMAC
  79         select CRYPTO_AES
  80         select CRYPTO_CBC
  81         select CRYPTO_SHA256
  82         select CRYPTO_RNG
  83         help
  84           This option provides support for create/encrypting/decrypting keys
  85           in the kernel.  Encrypted keys are kernel generated random numbers,
  86           which are encrypted/decrypted with a 'master' symmetric key. The
  87           'master' key can be either a trusted-key or user-key type.
  88           Userspace only ever sees/stores encrypted blobs.
  89
  90           If you are unsure as to whether this is required, answer N.
  91
  92 config KEY_DH_OPERATIONS
  93        bool "Diffie-Hellman operations on retained keys"
  94        depends on KEYS
  95        select CRYPTO
  96        select CRYPTO_HASH
  97        select CRYPTO_DH
  98        help
  99          This option provides support for calculating Diffie-Hellman
 100          public keys and shared secrets using values stored as keys
 101          in the kernel.
 102
 103          If you are unsure as to whether this is required, answer N.