xref: /openbmc/linux/security/Kconfig (revision a1e58bbd)
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_CAPABILITIES
77	bool "Default Linux Capabilities"
78	depends on SECURITY
79	default y
80	help
81	  This enables the "default" Linux capabilities functionality.
82	  If you are unsure how to answer this question, answer Y.
83
84config SECURITY_FILE_CAPABILITIES
85	bool "File POSIX Capabilities (EXPERIMENTAL)"
86	depends on (SECURITY=n || SECURITY_CAPABILITIES!=n) && EXPERIMENTAL
87	default n
88	help
89	  This enables filesystem capabilities, allowing you to give
90	  binaries a subset of root's powers without using setuid 0.
91
92	  If in doubt, answer N.
93
94config SECURITY_ROOTPLUG
95	bool "Root Plug Support"
96	depends on USB=y && SECURITY
97	help
98	  This is a sample LSM module that should only be used as such.
99	  It prevents any programs running with egid == 0 if a specific
100	  USB device is not present in the system.
101
102	  See <http://www.linuxjournal.com/article.php?sid=6279> for
103	  more information about this module.
104
105	  If you are unsure how to answer this question, answer N.
106
107config SECURITY_DEFAULT_MMAP_MIN_ADDR
108        int "Low address space to protect from user allocation"
109        depends on SECURITY
110        default 0
111        help
112	  This is the portion of low virtual memory which should be protected
113	  from userspace allocation.  Keeping a user from writing to low pages
114	  can help reduce the impact of kernel NULL pointer bugs.
115
116	  For most users with lots of address space a value of 65536 is
117	  reasonable and should cause no problems.  Programs which use vm86
118	  functionality would either need additional permissions from either
119	  the LSM or the capabilities module or have this protection disabled.
120
121	  This value can be changed after boot using the
122	  /proc/sys/vm/mmap_min_addr tunable.
123
124
125source security/selinux/Kconfig
126source security/smack/Kconfig
127
128endmenu
129
130