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 TRUSTED_KEYS
25	tristate "TRUSTED KEYS"
26	depends on KEYS && TCG_TPM
27	select CRYPTO
28	select CRYPTO_HMAC
29	select CRYPTO_SHA1
30	help
31	  This option provides support for creating, sealing, and unsealing
32	  keys in the kernel. Trusted keys are random number symmetric keys,
33	  generated and RSA-sealed by the TPM. The TPM only unseals the keys,
34	  if the boot PCRs and other criteria match.  Userspace will only ever
35	  see encrypted blobs.
36
37	  If you are unsure as to whether this is required, answer N.
38
39config ENCRYPTED_KEYS
40	tristate "ENCRYPTED KEYS"
41	depends on KEYS
42	select CRYPTO
43	select CRYPTO_HMAC
44	select CRYPTO_AES
45	select CRYPTO_CBC
46	select CRYPTO_SHA256
47	select CRYPTO_RNG
48	help
49	  This option provides support for create/encrypting/decrypting keys
50	  in the kernel.  Encrypted keys are kernel generated random numbers,
51	  which are encrypted/decrypted with a 'master' symmetric key. The
52	  'master' key can be either a trusted-key or user-key type.
53	  Userspace only ever sees/stores encrypted blobs.
54
55	  If you are unsure as to whether this is required, answer N.
56
57config KEYS_DEBUG_PROC_KEYS
58	bool "Enable the /proc/keys file by which keys may be viewed"
59	depends on KEYS
60	help
61	  This option turns on support for the /proc/keys file - through which
62	  can be listed all the keys on the system that are viewable by the
63	  reading process.
64
65	  The only keys included in the list are those that grant View
66	  permission to the reading process whether or not it possesses them.
67	  Note that LSM security checks are still performed, and may further
68	  filter out keys that the current process is not authorised to view.
69
70	  Only key attributes are listed here; key payloads are not included in
71	  the resulting table.
72
73	  If you are unsure as to whether this is required, answer N.
74
75config SECURITY_DMESG_RESTRICT
76	bool "Restrict unprivileged access to the kernel syslog"
77	default n
78	help
79	  This enforces restrictions on unprivileged users reading the kernel
80	  syslog via dmesg(8).
81
82	  If this option is not selected, no restrictions will be enforced
83	  unless the dmesg_restrict sysctl is explicitly set to (1).
84
85	  If you are unsure how to answer this question, answer N.
86
87config SECURITY
88	bool "Enable different security models"
89	depends on SYSFS
90	help
91	  This allows you to choose different security modules to be
92	  configured into your kernel.
93
94	  If this option is not selected, the default Linux security
95	  model will be used.
96
97	  If you are unsure how to answer this question, answer N.
98
99config SECURITYFS
100	bool "Enable the securityfs filesystem"
101	help
102	  This will build the securityfs filesystem.  It is currently used by
103	  the TPM bios character driver and IMA, an integrity provider.  It is
104	  not used by SELinux or SMACK.
105
106	  If you are unsure how to answer this question, answer N.
107
108config SECURITY_NETWORK
109	bool "Socket and Networking Security Hooks"
110	depends on SECURITY
111	help
112	  This enables the socket and networking security hooks.
113	  If enabled, a security module can use these hooks to
114	  implement socket and networking access controls.
115	  If you are unsure how to answer this question, answer N.
116
117config SECURITY_NETWORK_XFRM
118	bool "XFRM (IPSec) Networking Security Hooks"
119	depends on XFRM && SECURITY_NETWORK
120	help
121	  This enables the XFRM (IPSec) networking security hooks.
122	  If enabled, a security module can use these hooks to
123	  implement per-packet access controls based on labels
124	  derived from IPSec policy.  Non-IPSec communications are
125	  designated as unlabelled, and only sockets authorized
126	  to communicate unlabelled data can send without using
127	  IPSec.
128	  If you are unsure how to answer this question, answer N.
129
130config SECURITY_PATH
131	bool "Security hooks for pathname based access control"
132	depends on SECURITY
133	help
134	  This enables the security hooks for pathname based access control.
135	  If enabled, a security module can use these hooks to
136	  implement pathname based access controls.
137	  If you are unsure how to answer this question, answer N.
138
139config INTEL_TXT
140	bool "Enable Intel(R) Trusted Execution Technology (Intel(R) TXT)"
141	depends on HAVE_INTEL_TXT
142	help
143	  This option enables support for booting the kernel with the
144	  Trusted Boot (tboot) module. This will utilize
145	  Intel(R) Trusted Execution Technology to perform a measured launch
146	  of the kernel. If the system does not support Intel(R) TXT, this
147	  will have no effect.
148
149	  Intel TXT will provide higher assurance of system configuration and
150	  initial state as well as data reset protection.  This is used to
151	  create a robust initial kernel measurement and verification, which
152	  helps to ensure that kernel security mechanisms are functioning
153	  correctly. This level of protection requires a root of trust outside
154	  of the kernel itself.
155
156	  Intel TXT also helps solve real end user concerns about having
157	  confidence that their hardware is running the VMM or kernel that
158	  it was configured with, especially since they may be responsible for
159	  providing such assurances to VMs and services running on it.
160
161	  See <http://www.intel.com/technology/security/> for more information
162	  about Intel(R) TXT.
163	  See <http://tboot.sourceforge.net> for more information about tboot.
164	  See Documentation/intel_txt.txt for a description of how to enable
165	  Intel TXT support in a kernel boot.
166
167	  If you are unsure as to whether this is required, answer N.
168
169config LSM_MMAP_MIN_ADDR
170	int "Low address space for LSM to protect from user allocation"
171	depends on SECURITY && SECURITY_SELINUX
172	default 32768 if ARM
173	default 65536
174	help
175	  This is the portion of low virtual memory which should be protected
176	  from userspace allocation.  Keeping a user from writing to low pages
177	  can help reduce the impact of kernel NULL pointer bugs.
178
179	  For most ia64, ppc64 and x86 users with lots of address space
180	  a value of 65536 is reasonable and should cause no problems.
181	  On arm and other archs it should not be higher than 32768.
182	  Programs which use vm86 functionality or have some need to map
183	  this low address space will need the permission specific to the
184	  systems running LSM.
185
186source security/selinux/Kconfig
187source security/smack/Kconfig
188source security/tomoyo/Kconfig
189source security/apparmor/Kconfig
190
191source security/integrity/Kconfig
192
193choice
194	prompt "Default security module"
195	default DEFAULT_SECURITY_SELINUX if SECURITY_SELINUX
196	default DEFAULT_SECURITY_SMACK if SECURITY_SMACK
197	default DEFAULT_SECURITY_TOMOYO if SECURITY_TOMOYO
198	default DEFAULT_SECURITY_APPARMOR if SECURITY_APPARMOR
199	default DEFAULT_SECURITY_DAC
200
201	help
202	  Select the security module that will be used by default if the
203	  kernel parameter security= is not specified.
204
205	config DEFAULT_SECURITY_SELINUX
206		bool "SELinux" if SECURITY_SELINUX=y
207
208	config DEFAULT_SECURITY_SMACK
209		bool "Simplified Mandatory Access Control" if SECURITY_SMACK=y
210
211	config DEFAULT_SECURITY_TOMOYO
212		bool "TOMOYO" if SECURITY_TOMOYO=y
213
214	config DEFAULT_SECURITY_APPARMOR
215		bool "AppArmor" if SECURITY_APPARMOR=y
216
217	config DEFAULT_SECURITY_DAC
218		bool "Unix Discretionary Access Controls"
219
220endchoice
221
222config DEFAULT_SECURITY
223	string
224	default "selinux" if DEFAULT_SECURITY_SELINUX
225	default "smack" if DEFAULT_SECURITY_SMACK
226	default "tomoyo" if DEFAULT_SECURITY_TOMOYO
227	default "apparmor" if DEFAULT_SECURITY_APPARMOR
228	default "" if DEFAULT_SECURITY_DAC
229
230endmenu
231
232