1# 2# Security configuration 3# 4 5menu "Security options" 6 7config 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 24config 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 42config 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 54config 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 63config 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 76config SECURITY_FILE_CAPABILITIES 77 bool "File POSIX Capabilities (EXPERIMENTAL)" 78 depends on EXPERIMENTAL 79 default n 80 help 81 This enables filesystem capabilities, allowing you to give 82 binaries a subset of root's powers without using setuid 0. 83 84 If in doubt, answer N. 85 86config SECURITY_ROOTPLUG 87 bool "Root Plug Support" 88 depends on USB=y && SECURITY 89 help 90 This is a sample LSM module that should only be used as such. 91 It prevents any programs running with egid == 0 if a specific 92 USB device is not present in the system. 93 94 See <http://www.linuxjournal.com/article.php?sid=6279> for 95 more information about this module. 96 97 If you are unsure how to answer this question, answer N. 98 99config SECURITY_DEFAULT_MMAP_MIN_ADDR 100 int "Low address space to protect from user allocation" 101 depends on SECURITY 102 default 0 103 help 104 This is the portion of low virtual memory which should be protected 105 from userspace allocation. Keeping a user from writing to low pages 106 can help reduce the impact of kernel NULL pointer bugs. 107 108 For most ia64, ppc64 and x86 users with lots of address space 109 a value of 65536 is reasonable and should cause no problems. 110 On arm and other archs it should not be higher than 32768. 111 Programs which use vm86 functionality would either need additional 112 permissions from either the LSM or the capabilities module or have 113 this protection disabled. 114 115 This value can be changed after boot using the 116 /proc/sys/vm/mmap_min_addr tunable. 117 118 119source security/selinux/Kconfig 120source security/smack/Kconfig 121 122endmenu 123 124