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Linus Torvalds1da177e2005-04-16 15:20:36 -07001#
2# Security configuration
3#
4
5menu "Security options"
6
David Howellsf0894942012-05-11 10:56:56 +01007source security/keys/Kconfig
Linus Torvalds1da177e2005-04-16 15:20:36 -07008
Dan Rosenbergeaf06b22010-11-11 14:05:18 -08009config SECURITY_DMESG_RESTRICT
10 bool "Restrict unprivileged access to the kernel syslog"
11 default n
12 help
13 This enforces restrictions on unprivileged users reading the kernel
14 syslog via dmesg(8).
15
16 If this option is not selected, no restrictions will be enforced
17 unless the dmesg_restrict sysctl is explicitly set to (1).
18
19 If you are unsure how to answer this question, answer N.
20
Linus Torvalds1da177e2005-04-16 15:20:36 -070021config SECURITY
22 bool "Enable different security models"
Adrian Bunk2c405792005-08-22 18:20:50 +020023 depends on SYSFS
Iulia Manda28138932015-04-15 16:16:41 -070024 depends on MULTIUSER
Linus Torvalds1da177e2005-04-16 15:20:36 -070025 help
26 This allows you to choose different security modules to be
27 configured into your kernel.
28
29 If this option is not selected, the default Linux security
30 model will be used.
31
32 If you are unsure how to answer this question, answer N.
33
Eric Parisda318942008-08-22 11:35:57 -040034config SECURITYFS
35 bool "Enable the securityfs filesystem"
36 help
37 This will build the securityfs filesystem. It is currently used by
Mimi Zohar3323eec2009-02-04 09:06:58 -050038 the TPM bios character driver and IMA, an integrity provider. It is
39 not used by SELinux or SMACK.
Eric Parisda318942008-08-22 11:35:57 -040040
41 If you are unsure how to answer this question, answer N.
42
Linus Torvalds1da177e2005-04-16 15:20:36 -070043config SECURITY_NETWORK
44 bool "Socket and Networking Security Hooks"
45 depends on SECURITY
46 help
47 This enables the socket and networking security hooks.
48 If enabled, a security module can use these hooks to
49 implement socket and networking access controls.
50 If you are unsure how to answer this question, answer N.
51
Trent Jaegerdf718372005-12-13 23:12:27 -080052config SECURITY_NETWORK_XFRM
53 bool "XFRM (IPSec) Networking Security Hooks"
54 depends on XFRM && SECURITY_NETWORK
55 help
56 This enables the XFRM (IPSec) networking security hooks.
57 If enabled, a security module can use these hooks to
58 implement per-packet access controls based on labels
59 derived from IPSec policy. Non-IPSec communications are
60 designated as unlabelled, and only sockets authorized
61 to communicate unlabelled data can send without using
62 IPSec.
63 If you are unsure how to answer this question, answer N.
64
Kentaro Takedabe6d3e52008-12-17 13:24:15 +090065config SECURITY_PATH
66 bool "Security hooks for pathname based access control"
67 depends on SECURITY
68 help
69 This enables the security hooks for pathname based access control.
70 If enabled, a security module can use these hooks to
71 implement pathname based access controls.
72 If you are unsure how to answer this question, answer N.
73
Joseph Cihula31625342009-06-30 19:30:59 -070074config INTEL_TXT
75 bool "Enable Intel(R) Trusted Execution Technology (Intel(R) TXT)"
Shane Wang69575d32009-09-01 18:25:07 -070076 depends on HAVE_INTEL_TXT
Joseph Cihula31625342009-06-30 19:30:59 -070077 help
78 This option enables support for booting the kernel with the
79 Trusted Boot (tboot) module. This will utilize
80 Intel(R) Trusted Execution Technology to perform a measured launch
81 of the kernel. If the system does not support Intel(R) TXT, this
82 will have no effect.
83
Arnaldo Carvalho de Melo3c556e42009-08-12 12:00:40 -030084 Intel TXT will provide higher assurance of system configuration and
Joseph Cihula31625342009-06-30 19:30:59 -070085 initial state as well as data reset protection. This is used to
86 create a robust initial kernel measurement and verification, which
87 helps to ensure that kernel security mechanisms are functioning
88 correctly. This level of protection requires a root of trust outside
89 of the kernel itself.
90
91 Intel TXT also helps solve real end user concerns about having
92 confidence that their hardware is running the VMM or kernel that
Arnaldo Carvalho de Melo3c556e42009-08-12 12:00:40 -030093 it was configured with, especially since they may be responsible for
Joseph Cihula31625342009-06-30 19:30:59 -070094 providing such assurances to VMs and services running on it.
95
96 See <http://www.intel.com/technology/security/> for more information
97 about Intel(R) TXT.
98 See <http://tboot.sourceforge.net> for more information about tboot.
99 See Documentation/intel_txt.txt for a description of how to enable
100 Intel TXT support in a kernel boot.
101
102 If you are unsure as to whether this is required, answer N.
103
Eric Paris788084a2009-07-31 12:54:11 -0400104config LSM_MMAP_MIN_ADDR
Andreas Schwab024e6cb2009-08-18 22:14:29 +0200105 int "Low address space for LSM to protect from user allocation"
Eric Paris788084a2009-07-31 12:54:11 -0400106 depends on SECURITY && SECURITY_SELINUX
Colin Cross530b0992014-02-04 02:15:32 +0000107 default 32768 if ARM || (ARM64 && COMPAT)
Dave Jonesa58578e2009-08-18 13:47:37 -0400108 default 65536
Eric Paris788084a2009-07-31 12:54:11 -0400109 help
110 This is the portion of low virtual memory which should be protected
111 from userspace allocation. Keeping a user from writing to low pages
112 can help reduce the impact of kernel NULL pointer bugs.
113
114 For most ia64, ppc64 and x86 users with lots of address space
115 a value of 65536 is reasonable and should cause no problems.
116 On arm and other archs it should not be higher than 32768.
117 Programs which use vm86 functionality or have some need to map
118 this low address space will need the permission specific to the
119 systems running LSM.
120
Kees Cookf5509cc2016-06-07 11:05:33 -0700121config HAVE_HARDENED_USERCOPY_ALLOCATOR
122 bool
123 help
124 The heap allocator implements __check_heap_object() for
125 validating memory ranges against heap object sizes in
126 support of CONFIG_HARDENED_USERCOPY.
127
128config HAVE_ARCH_HARDENED_USERCOPY
129 bool
130 help
131 The architecture supports CONFIG_HARDENED_USERCOPY by
132 calling check_object_size() just before performing the
133 userspace copies in the low level implementation of
134 copy_to_user() and copy_from_user().
135
136config HARDENED_USERCOPY
137 bool "Harden memory copies between kernel and userspace"
138 depends on HAVE_ARCH_HARDENED_USERCOPY
Linus Torvalds6040e572016-08-19 12:47:01 -0700139 depends on HAVE_HARDENED_USERCOPY_ALLOCATOR
Kees Cookf5509cc2016-06-07 11:05:33 -0700140 select BUG
141 help
142 This option checks for obviously wrong memory regions when
143 copying memory to/from the kernel (via copy_to_user() and
144 copy_from_user() functions) by rejecting memory ranges that
145 are larger than the specified heap object, span multiple
146 separately allocates pages, are not on the process stack,
147 or are part of the kernel text. This kills entire classes
148 of heap overflow exploits and similar kernel memory exposures.
149
Kees Cook8e1f74e2016-09-07 09:54:34 -0700150config HARDENED_USERCOPY_PAGESPAN
151 bool "Refuse to copy allocations that span multiple pages"
152 depends on HARDENED_USERCOPY
Linus Torvalds80a77042016-09-07 14:03:49 -0700153 depends on EXPERT
Kees Cook8e1f74e2016-09-07 09:54:34 -0700154 help
155 When a multi-page allocation is done without __GFP_COMP,
156 hardened usercopy will reject attempts to copy it. There are,
157 however, several cases of this in the kernel that have not all
158 been removed. This config is intended to be used only while
159 trying to find such users.
160
Greg Kroah-Hartman64e90a8a2017-01-16 16:22:39 +0100161config STATIC_USERMODEHELPER
162 bool "Force all usermode helper calls through a single binary"
163 help
164 By default, the kernel can call many different userspace
165 binary programs through the "usermode helper" kernel
166 interface. Some of these binaries are statically defined
167 either in the kernel code itself, or as a kernel configuration
168 option. However, some of these are dynamically created at
169 runtime, or can be modified after the kernel has started up.
170 To provide an additional layer of security, route all of these
171 calls through a single executable that can not have its name
172 changed.
173
174 Note, it is up to this single binary to then call the relevant
175 "real" usermode helper binary, based on the first argument
176 passed to it. If desired, this program can filter and pick
177 and choose what real programs are called.
178
179 If you wish for all usermode helper programs are to be
180 disabled, choose this option and then set
181 STATIC_USERMODEHELPER_PATH to an empty string.
182
183config STATIC_USERMODEHELPER_PATH
184 string "Path to the static usermode helper binary"
185 depends on STATIC_USERMODEHELPER
186 default "/sbin/usermode-helper"
187 help
188 The binary called by the kernel when any usermode helper
189 program is wish to be run. The "real" application's name will
190 be in the first argument passed to this program on the command
191 line.
192
193 If you wish for all usermode helper programs to be disabled,
194 specify an empty string here (i.e. "").
195
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196source security/selinux/Kconfig
Casey Schauflere114e472008-02-04 22:29:50 -0800197source security/smack/Kconfig
Kentaro Takeda00d7d6f2009-02-05 17:18:17 +0900198source security/tomoyo/Kconfig
John Johansenf9ad1af2010-07-29 14:48:08 -0700199source security/apparmor/Kconfig
Kees Cook9b091552016-04-20 15:46:28 -0700200source security/loadpin/Kconfig
Kees Cook2d514482011-12-21 12:17:04 -0800201source security/yama/Kconfig
Linus Torvalds1da177e2005-04-16 15:20:36 -0700202
Mimi Zoharf381c272011-03-09 14:13:22 -0500203source security/integrity/Kconfig
Mimi Zohar3323eec2009-02-04 09:06:58 -0500204
John Johansen6e65f922009-11-05 17:03:20 -0800205choice
206 prompt "Default security module"
207 default DEFAULT_SECURITY_SELINUX if SECURITY_SELINUX
208 default DEFAULT_SECURITY_SMACK if SECURITY_SMACK
209 default DEFAULT_SECURITY_TOMOYO if SECURITY_TOMOYO
John Johansenf9ad1af2010-07-29 14:48:08 -0700210 default DEFAULT_SECURITY_APPARMOR if SECURITY_APPARMOR
John Johansen6e65f922009-11-05 17:03:20 -0800211 default DEFAULT_SECURITY_DAC
212
213 help
214 Select the security module that will be used by default if the
215 kernel parameter security= is not specified.
216
217 config DEFAULT_SECURITY_SELINUX
218 bool "SELinux" if SECURITY_SELINUX=y
219
220 config DEFAULT_SECURITY_SMACK
221 bool "Simplified Mandatory Access Control" if SECURITY_SMACK=y
222
223 config DEFAULT_SECURITY_TOMOYO
224 bool "TOMOYO" if SECURITY_TOMOYO=y
225
John Johansenf9ad1af2010-07-29 14:48:08 -0700226 config DEFAULT_SECURITY_APPARMOR
227 bool "AppArmor" if SECURITY_APPARMOR=y
228
John Johansen6e65f922009-11-05 17:03:20 -0800229 config DEFAULT_SECURITY_DAC
230 bool "Unix Discretionary Access Controls"
231
232endchoice
233
234config DEFAULT_SECURITY
235 string
236 default "selinux" if DEFAULT_SECURITY_SELINUX
237 default "smack" if DEFAULT_SECURITY_SMACK
238 default "tomoyo" if DEFAULT_SECURITY_TOMOYO
John Johansenf9ad1af2010-07-29 14:48:08 -0700239 default "apparmor" if DEFAULT_SECURITY_APPARMOR
John Johansen6e65f922009-11-05 17:03:20 -0800240 default "" if DEFAULT_SECURITY_DAC
241
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242endmenu
243