security/selinux/Kconfig

   1 # SPDX-License-Identifier: GPL-2.0-only
   2 config SECURITY_SELINUX
   3         bool "NSA SELinux Support"
   4         depends on SECURITY_NETWORK && AUDIT && NET && INET
   5         select NETWORK_SECMARK
   6         default n
   7         help
   8           This selects NSA Security-Enhanced Linux (SELinux).
   9           You will also need a policy configuration and a labeled filesystem.
  10           If you are unsure how to answer this question, answer N.
  11
  12 config SECURITY_SELINUX_BOOTPARAM
  13         bool "NSA SELinux boot parameter"
  14         depends on SECURITY_SELINUX
  15         default n
  16         help
  17           This option adds a kernel parameter 'selinux', which allows SELinux
  18           to be disabled at boot.  If this option is selected, SELinux
  19           functionality can be disabled with selinux=0 on the kernel
  20           command line.  The purpose of this option is to allow a single
  21           kernel image to be distributed with SELinux built in, but not
  22           necessarily enabled.
  23
  24           If you are unsure how to answer this question, answer N.
  25
  26 config SECURITY_SELINUX_DISABLE
  27         bool "NSA SELinux runtime disable"
  28         depends on SECURITY_SELINUX
  29         select SECURITY_WRITABLE_HOOKS
  30         default n
  31         help
  32           This option enables writing to a selinuxfs node 'disable', which
  33           allows SELinux to be disabled at runtime prior to the policy load.
  34           SELinux will then remain disabled until the next boot.
  35           This option is similar to the selinux=0 boot parameter, but is to
  36           support runtime disabling of SELinux, e.g. from /sbin/init, for
  37           portability across platforms where boot parameters are difficult
  38           to employ.
  39
  40           NOTE: selecting this option will disable the '__ro_after_init'
  41           kernel hardening feature for security hooks.   Please consider
  42           using the selinux=0 boot parameter instead of enabling this
  43           option.
  44
  45           WARNING: this option is deprecated and will be removed in a future
  46           kernel release.
  47
  48           If you are unsure how to answer this question, answer N.
  49
  50 config SECURITY_SELINUX_DEVELOP
  51         bool "NSA SELinux Development Support"
  52         depends on SECURITY_SELINUX
  53         default y
  54         help
  55           This enables the development support option of NSA SELinux,
  56           which is useful for experimenting with SELinux and developing
  57           policies.  If unsure, say Y.  With this option enabled, the
  58           kernel will start in permissive mode (log everything, deny nothing)
  59           unless you specify enforcing=1 on the kernel command line.  You
  60           can interactively toggle the kernel between enforcing mode and
  61           permissive mode (if permitted by the policy) via
  62           /sys/fs/selinux/enforce.
  63
  64 config SECURITY_SELINUX_AVC_STATS
  65         bool "NSA SELinux AVC Statistics"
  66         depends on SECURITY_SELINUX
  67         default y
  68         help
  69           This option collects access vector cache statistics to
  70           /sys/fs/selinux/avc/cache_stats, which may be monitored via
  71           tools such as avcstat.
  72
  73 config SECURITY_SELINUX_CHECKREQPROT_VALUE
  74         int "NSA SELinux checkreqprot default value"
  75         depends on SECURITY_SELINUX
  76         range 0 1
  77         default 0
  78         help
  79           This option sets the default value for the 'checkreqprot' flag
  80           that determines whether SELinux checks the protection requested
  81           by the application or the protection that will be applied by the
  82           kernel (including any implied execute for read-implies-exec) for
  83           mmap and mprotect calls.  If this option is set to 0 (zero),
  84           SELinux will default to checking the protection that will be applied
  85           by the kernel.  If this option is set to 1 (one), SELinux will
  86           default to checking the protection requested by the application.
  87           The checkreqprot flag may be changed from the default via the
  88           'checkreqprot=' boot parameter.  It may also be changed at runtime
  89           via /sys/fs/selinux/checkreqprot if authorized by policy.
  90
  91           WARNING: this option is deprecated and will be removed in a future
  92           kernel release.
  93
  94           If you are unsure how to answer this question, answer 0.
  95
  96 config SECURITY_SELINUX_SIDTAB_HASH_BITS
  97         int "NSA SELinux sidtab hashtable size"
  98         depends on SECURITY_SELINUX
  99         range 8 13
 100         default 9
 101         help
 102           This option sets the number of buckets used in the sidtab hashtable
 103           to 2^SECURITY_SELINUX_SIDTAB_HASH_BITS buckets. The number of hash
 104           collisions may be viewed at /sys/fs/selinux/ss/sidtab_hash_stats. If
 105           chain lengths are high (e.g. > 20) then selecting a higher value here
 106           will ensure that lookups times are short and stable.
 107
 108 config SECURITY_SELINUX_SID2STR_CACHE_SIZE
 109         int "NSA SELinux SID to context string translation cache size"
 110         depends on SECURITY_SELINUX
 111         default 256
 112         help
 113           This option defines the size of the internal SID -> context string
 114           cache, which improves the performance of context to string
 115           conversion.  Setting this option to 0 disables the cache completely.
 116
 117           If unsure, keep the default value.