security/Kconfig

   1 #
   2 # Security configuration
   3 #
   4
   5 menu "Security options"
   6
   7 source security/keys/Kconfig
   8
   9 config SECURITY_DMESG_RESTRICT
  10         bool "Restrict unprivileged access to the kernel syslog"
  11         default n
  12         help
  13           This enforces restrictions on unprivileged users reading the kernel
  14           syslog via dmesg(8).
  15
  16           If this option is not selected, no restrictions will be enforced
  17           unless the dmesg_restrict sysctl is explicitly set to (1).
  18
  19           If you are unsure how to answer this question, answer N.
  20
  21 config SECURITY
  22         bool "Enable different security models"
  23         depends on SYSFS
  24         depends on MULTIUSER
  25         help
  26           This allows you to choose different security modules to be
  27           configured into your kernel.
  28
  29           If this option is not selected, the default Linux security
  30           model will be used.
  31
  32           If you are unsure how to answer this question, answer N.
  33
  34 config PAGE_TABLE_ISOLATION
  35         bool "Remove the kernel mapping in user mode"
  36         default y
  37         depends on X86_64 && SMP
  38         help
  39           This enforces a strict kernel and user space isolation, in order
  40           to close hardware side channels on kernel address information.
  41
  42           If you are unsure how to answer this question, answer Y.
  43
  44 config SECURITYFS
  45         bool "Enable the securityfs filesystem"
  46         help
  47           This will build the securityfs filesystem.  It is currently used by
  48           the TPM bios character driver and IMA, an integrity provider.  It is
  49           not used by SELinux or SMACK.
  50
  51           If you are unsure how to answer this question, answer N.
  52
  53 config SECURITY_NETWORK
  54         bool "Socket and Networking Security Hooks"
  55         depends on SECURITY
  56         help
  57           This enables the socket and networking security hooks.
  58           If enabled, a security module can use these hooks to
  59           implement socket and networking access controls.
  60           If you are unsure how to answer this question, answer N.
  61
  62 config SECURITY_NETWORK_XFRM
  63         bool "XFRM (IPSec) Networking Security Hooks"
  64         depends on XFRM && SECURITY_NETWORK
  65         help
  66           This enables the XFRM (IPSec) networking security hooks.
  67           If enabled, a security module can use these hooks to
  68           implement per-packet access controls based on labels
  69           derived from IPSec policy.  Non-IPSec communications are
  70           designated as unlabelled, and only sockets authorized
  71           to communicate unlabelled data can send without using
  72           IPSec.
  73           If you are unsure how to answer this question, answer N.
  74
  75 config SECURITY_PATH
  76         bool "Security hooks for pathname based access control"
  77         depends on SECURITY
  78         help
  79           This enables the security hooks for pathname based access control.
  80           If enabled, a security module can use these hooks to
  81           implement pathname based access controls.
  82           If you are unsure how to answer this question, answer N.
  83
  84 config INTEL_TXT
  85         bool "Enable Intel(R) Trusted Execution Technology (Intel(R) TXT)"
  86         depends on HAVE_INTEL_TXT
  87         help
  88           This option enables support for booting the kernel with the
  89           Trusted Boot (tboot) module. This will utilize
  90           Intel(R) Trusted Execution Technology to perform a measured launch
  91           of the kernel. If the system does not support Intel(R) TXT, this
  92           will have no effect.
  93
  94           Intel TXT will provide higher assurance of system configuration and
  95           initial state as well as data reset protection.  This is used to
  96           create a robust initial kernel measurement and verification, which
  97           helps to ensure that kernel security mechanisms are functioning
  98           correctly. This level of protection requires a root of trust outside
  99           of the kernel itself.
 100
 101           Intel TXT also helps solve real end user concerns about having
 102           confidence that their hardware is running the VMM or kernel that
 103           it was configured with, especially since they may be responsible for
 104           providing such assurances to VMs and services running on it.
 105
 106           See <http://www.intel.com/technology/security/> for more information
 107           about Intel(R) TXT.
 108           See <http://tboot.sourceforge.net> for more information about tboot.
 109           See Documentation/intel_txt.txt for a description of how to enable
 110           Intel TXT support in a kernel boot.
 111
 112           If you are unsure as to whether this is required, answer N.
 113
 114 config LSM_MMAP_MIN_ADDR
 115         int "Low address space for LSM to protect from user allocation"
 116         depends on SECURITY && SECURITY_SELINUX
 117         default 32768 if ARM || (ARM64 && COMPAT)
 118         default 65536
 119         help
 120           This is the portion of low virtual memory which should be protected
 121           from userspace allocation.  Keeping a user from writing to low pages
 122           can help reduce the impact of kernel NULL pointer bugs.
 123
 124           For most ia64, ppc64 and x86 users with lots of address space
 125           a value of 65536 is reasonable and should cause no problems.
 126           On arm and other archs it should not be higher than 32768.
 127           Programs which use vm86 functionality or have some need to map
 128           this low address space will need the permission specific to the
 129           systems running LSM.
 130
 131 source security/selinux/Kconfig
 132 source security/smack/Kconfig
 133 source security/tomoyo/Kconfig
 134 source security/apparmor/Kconfig
 135 source security/yama/Kconfig
 136
 137 source security/integrity/Kconfig
 138
 139 choice
 140         prompt "Default security module"
 141         default DEFAULT_SECURITY_SELINUX if SECURITY_SELINUX
 142         default DEFAULT_SECURITY_SMACK if SECURITY_SMACK
 143         default DEFAULT_SECURITY_TOMOYO if SECURITY_TOMOYO
 144         default DEFAULT_SECURITY_APPARMOR if SECURITY_APPARMOR
 145         default DEFAULT_SECURITY_DAC
 146
 147         help
 148           Select the security module that will be used by default if the
 149           kernel parameter security= is not specified.
 150
 151         config DEFAULT_SECURITY_SELINUX
 152                 bool "SELinux" if SECURITY_SELINUX=y
 153
 154         config DEFAULT_SECURITY_SMACK
 155                 bool "Simplified Mandatory Access Control" if SECURITY_SMACK=y
 156
 157         config DEFAULT_SECURITY_TOMOYO
 158                 bool "TOMOYO" if SECURITY_TOMOYO=y
 159
 160         config DEFAULT_SECURITY_APPARMOR
 161                 bool "AppArmor" if SECURITY_APPARMOR=y
 162
 163         config DEFAULT_SECURITY_DAC
 164                 bool "Unix Discretionary Access Controls"
 165
 166 endchoice
 167
 168 config DEFAULT_SECURITY
 169         string
 170         default "selinux" if DEFAULT_SECURITY_SELINUX
 171         default "smack" if DEFAULT_SECURITY_SMACK
 172         default "tomoyo" if DEFAULT_SECURITY_TOMOYO
 173         default "apparmor" if DEFAULT_SECURITY_APPARMOR
 174         default "" if DEFAULT_SECURITY_DAC
 175
 176 endmenu
 177