# # 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_CAPABILITIES bool "Default Linux Capabilities" depends on SECURITY default y help This enables the "default" Linux capabilities functionality. If you are unsure how to answer this question, answer Y. config SECURITY_FILE_CAPABILITIES bool "File POSIX Capabilities (EXPERIMENTAL)" depends on (SECURITY=n || SECURITY_CAPABILITIES!=n) && EXPERIMENTAL 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