xref: /openbmc/linux/security/Kconfig (revision 84aaa7ab)

#
# Security configuration
#

menu "Security options"

config KEYS
	bool "Enable access key retention support"
	help
	  This option provides support for retaining authentication tokens and
	  access keys in the kernel.

	  It also includes provision of methods by which such keys might be
	  associated with a process so that network filesystems, encryption
	  support and the like can find them.

	  Furthermore, a special type of key is available that acts as keyring:
	  a searchable sequence of keys. Each process is equipped with access
	  to five standard keyrings: UID-specific, GID-specific, session,
	  process and thread.

	  If you are unsure as to whether this is required, answer N.

config KEYS_DEBUG_PROC_KEYS
	bool "Enable the /proc/keys file by which keys may be viewed"
	depends on KEYS
	help
	  This option turns on support for the /proc/keys file - through which
	  can be listed all the keys on the system that are viewable by the
	  reading process.

	  The only keys included in the list are those that grant View
	  permission to the reading process whether or not it possesses them.
	  Note that LSM security checks are still performed, and may further
	  filter out keys that the current process is not authorised to view.

	  Only key attributes are listed here; key payloads are not included in
	  the resulting table.

	  If you are unsure as to whether this is required, answer N.

config SECURITY
	bool "Enable different security models"
	depends on SYSFS
	help
	  This allows you to choose different security modules to be
	  configured into your kernel.

	  If this option is not selected, the default Linux security
	  model will be used.

	  If you are unsure how to answer this question, answer N.

config SECURITY_NETWORK
	bool "Socket and Networking Security Hooks"
	depends on SECURITY
	help
	  This enables the socket and networking security hooks.
	  If enabled, a security module can use these hooks to
	  implement socket and networking access controls.
	  If you are unsure how to answer this question, answer N.

config SECURITY_NETWORK_XFRM
	bool "XFRM (IPSec) Networking Security Hooks"
	depends on XFRM && SECURITY_NETWORK
	help
	  This enables the XFRM (IPSec) networking security hooks.
	  If enabled, a security module can use these hooks to
	  implement per-packet access controls based on labels
	  derived from IPSec policy.  Non-IPSec communications are
	  designated as unlabelled, and only sockets authorized
	  to communicate unlabelled data can send without using
	  IPSec.
	  If you are unsure how to answer this question, answer N.

config SECURITY_FILE_CAPABILITIES
	bool "File POSIX Capabilities"
	default n
	help
	  This enables filesystem capabilities, allowing you to give
	  binaries a subset of root's powers without using setuid 0.

	  If in doubt, answer N.

config SECURITY_ROOTPLUG
	bool "Root Plug Support"
	depends on USB=y && SECURITY
	help
	  This is a sample LSM module that should only be used as such.
	  It prevents any programs running with egid == 0 if a specific
	  USB device is not present in the system.

	  See <http://www.linuxjournal.com/article.php?sid=6279> for
	  more information about this module.

	  If you are unsure how to answer this question, answer N.

config SECURITY_DEFAULT_MMAP_MIN_ADDR
        int "Low address space to protect from user allocation"
        depends on SECURITY
        default 0
        help
	  This is the portion of low virtual memory which should be protected
	  from userspace allocation.  Keeping a user from writing to low pages
	  can help reduce the impact of kernel NULL pointer bugs.

	  For most ia64, ppc64 and x86 users with lots of address space
	  a value of 65536 is reasonable and should cause no problems.
	  On arm and other archs it should not be higher than 32768.
	  Programs which use vm86 functionality would either need additional
	  permissions from either the LSM or the capabilities module or have
	  this protection disabled.

	  This value can be changed after boot using the
	  /proc/sys/vm/mmap_min_addr tunable.


source security/selinux/Kconfig
source security/smack/Kconfig

endmenu