xref: /openbmc/linux/security/Kconfig (revision b627b4ed)
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 SECURITYFS
55	bool "Enable the securityfs filesystem"
56	help
57	  This will build the securityfs filesystem.  It is currently used by
58	  the TPM bios character driver and IMA, an integrity provider.  It is
59	  not used by SELinux or SMACK.
60
61	  If you are unsure how to answer this question, answer N.
62
63config SECURITY_NETWORK
64	bool "Socket and Networking Security Hooks"
65	depends on SECURITY
66	help
67	  This enables the socket and networking security hooks.
68	  If enabled, a security module can use these hooks to
69	  implement socket and networking access controls.
70	  If you are unsure how to answer this question, answer N.
71
72config SECURITY_NETWORK_XFRM
73	bool "XFRM (IPSec) Networking Security Hooks"
74	depends on XFRM && SECURITY_NETWORK
75	help
76	  This enables the XFRM (IPSec) networking security hooks.
77	  If enabled, a security module can use these hooks to
78	  implement per-packet access controls based on labels
79	  derived from IPSec policy.  Non-IPSec communications are
80	  designated as unlabelled, and only sockets authorized
81	  to communicate unlabelled data can send without using
82	  IPSec.
83	  If you are unsure how to answer this question, answer N.
84
85config SECURITY_PATH
86	bool "Security hooks for pathname based access control"
87	depends on SECURITY
88	help
89	  This enables the security hooks for pathname based access control.
90	  If enabled, a security module can use these hooks to
91	  implement pathname based access controls.
92	  If you are unsure how to answer this question, answer N.
93
94config SECURITY_FILE_CAPABILITIES
95	bool "File POSIX Capabilities"
96	default n
97	help
98	  This enables filesystem capabilities, allowing you to give
99	  binaries a subset of root's powers without using setuid 0.
100
101	  If in doubt, answer N.
102
103config SECURITY_ROOTPLUG
104	bool "Root Plug Support"
105	depends on USB=y && SECURITY
106	help
107	  This is a sample LSM module that should only be used as such.
108	  It prevents any programs running with egid == 0 if a specific
109	  USB device is not present in the system.
110
111	  See <http://www.linuxjournal.com/article.php?sid=6279> for
112	  more information about this module.
113
114	  If you are unsure how to answer this question, answer N.
115
116config SECURITY_DEFAULT_MMAP_MIN_ADDR
117        int "Low address space to protect from user allocation"
118        depends on SECURITY
119        default 0
120        help
121	  This is the portion of low virtual memory which should be protected
122	  from userspace allocation.  Keeping a user from writing to low pages
123	  can help reduce the impact of kernel NULL pointer bugs.
124
125	  For most ia64, ppc64 and x86 users with lots of address space
126	  a value of 65536 is reasonable and should cause no problems.
127	  On arm and other archs it should not be higher than 32768.
128	  Programs which use vm86 functionality would either need additional
129	  permissions from either the LSM or the capabilities module or have
130	  this protection disabled.
131
132	  This value can be changed after boot using the
133	  /proc/sys/vm/mmap_min_addr tunable.
134
135
136source security/selinux/Kconfig
137source security/smack/Kconfig
138source security/tomoyo/Kconfig
139
140source security/integrity/ima/Kconfig
141
142endmenu
143
144