security/Kconfig

   1 #
   2 # Security configuration
   3 #
   4
   5 menu "Security options"
   6
   7 config KEYS
   8         bool "Enable access key retention support"
   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
  24 config KEYS_DEBUG_PROC_KEYS
  25         bool "Enable the /proc/keys file by which keys may be viewed"
  26         depends on KEYS
  27         help
  28           This option turns on support for the /proc/keys file - through which
  29           can be listed all the keys on the system that are viewable by the
  30           reading process.
  31
  32           The only keys included in the list are those that grant View
  33           permission to the reading process whether or not it possesses them.
  34           Note that LSM security checks are still performed, and may further
  35           filter out keys that the current process is not authorised to view.
  36
  37           Only key attributes are listed here; key payloads are not included in
  38           the resulting table.
  39
  40           If you are unsure as to whether this is required, answer N.
  41
  42 config SECURITY
  43         bool "Enable different security models"
  44         depends on SYSFS
  45         help
  46           This allows you to choose different security modules to be
  47           configured into your kernel.
  48
  49           If this option is not selected, the default Linux security
  50           model will be used.
  51
  52           If you are unsure how to answer this question, answer N.
  53
  54 config SECURITY_NETWORK
  55         bool "Socket and Networking Security Hooks"
  56         depends on SECURITY
  57         help
  58           This enables the socket and networking security hooks.
  59           If enabled, a security module can use these hooks to
  60           implement socket and networking access controls.
  61           If you are unsure how to answer this question, answer N.
  62
  63 config SECURITY_NETWORK_XFRM
  64         bool "XFRM (IPSec) Networking Security Hooks"
  65         depends on XFRM && SECURITY_NETWORK
  66         help
  67           This enables the XFRM (IPSec) networking security hooks.
  68           If enabled, a security module can use these hooks to
  69           implement per-packet access controls based on labels
  70           derived from IPSec policy.  Non-IPSec communications are
  71           designated as unlabelled, and only sockets authorized
  72           to communicate unlabelled data can send without using
  73           IPSec.
  74           If you are unsure how to answer this question, answer N.
  75
  76 config SECURITY_CAPABILITIES
  77         bool "Default Linux Capabilities"
  78         depends on SECURITY
  79         default y
  80         help
  81           This enables the "default" Linux capabilities functionality.
  82           If you are unsure how to answer this question, answer Y.
  83
  84 config SECURITY_FILE_CAPABILITIES
  85         bool "File POSIX Capabilities (EXPERIMENTAL)"
  86         depends on (SECURITY=n || SECURITY_CAPABILITIES!=n) && EXPERIMENTAL
  87         default n
  88         help
  89           This enables filesystem capabilities, allowing you to give
  90           binaries a subset of root's powers without using setuid 0.
  91
  92           If in doubt, answer N.
  93
  94 config SECURITY_ROOTPLUG
  95         bool "Root Plug Support"
  96         depends on USB=y && SECURITY
  97         help
  98           This is a sample LSM module that should only be used as such.
  99           It prevents any programs running with egid == 0 if a specific
 100           USB device is not present in the system.
 101
 102           See <http://www.linuxjournal.com/article.php?sid=6279> for
 103           more information about this module.
 104
 105           If you are unsure how to answer this question, answer N.
 106
 107 config SECURITY_DEFAULT_MMAP_MIN_ADDR
 108         int "Low address space to protect from user allocation"
 109         depends on SECURITY
 110         default 0
 111         help
 112           This is the portion of low virtual memory which should be protected
 113           from userspace allocation.  Keeping a user from writing to low pages
 114           can help reduce the impact of kernel NULL pointer bugs.
 115
 116           For most ia64, ppc64 and x86 users with lots of address space
 117           a value of 65536 is reasonable and should cause no problems.
 118           On arm and other archs it should not be higher than 32768.
 119           Programs which use vm86 functionality would either need additional
 120           permissions from either the LSM or the capabilities module or have
 121           this protection disabled.
 122
 123           This value can be changed after boot using the
 124           /proc/sys/vm/mmap_min_addr tunable.
 125
 126
 127 source security/selinux/Kconfig
 128 source security/smack/Kconfig
 129
 130 endmenu
 131