1
2
3
4
5menu "Security options"
6
7source security/keys/Kconfig
8
9config 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
21config SECURITY
22 bool "Enable different security models"
23 depends on SYSFS
24 depends on MULTIUSER
25 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
34config SECURITYFS
35 bool "Enable the securityfs filesystem"
36 help
37 This will build the securityfs filesystem. It is currently used by
38 the TPM bios character driver and IMA, an integrity provider. It is
39 not used by SELinux or SMACK.
40
41 If you are unsure how to answer this question, answer N.
42
43config 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
52config 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
65config 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
74config INTEL_TXT
75 bool "Enable Intel(R) Trusted Execution Technology (Intel(R) TXT)"
76 depends on HAVE_INTEL_TXT
77 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
84 Intel TXT will provide higher assurance of system configuration and
85 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
93 it was configured with, especially since they may be responsible for
94 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
104config LSM_MMAP_MIN_ADDR
105 int "Low address space for LSM to protect from user allocation"
106 depends on SECURITY && SECURITY_SELINUX
107 default 32768 if ARM || (ARM64 && COMPAT)
108 default 65536
109 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
121config 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
139 depends on HAVE_HARDENED_USERCOPY_ALLOCATOR
140 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
150config HARDENED_USERCOPY_PAGESPAN
151 bool "Refuse to copy allocations that span multiple pages"
152 depends on HARDENED_USERCOPY
153 depends on EXPERT
154 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
161source security/selinux/Kconfig
162source security/smack/Kconfig
163source security/tomoyo/Kconfig
164source security/apparmor/Kconfig
165source security/loadpin/Kconfig
166source security/yama/Kconfig
167
168source security/integrity/Kconfig
169
170choice
171 prompt "Default security module"
172 default DEFAULT_SECURITY_SELINUX if SECURITY_SELINUX
173 default DEFAULT_SECURITY_SMACK if SECURITY_SMACK
174 default DEFAULT_SECURITY_TOMOYO if SECURITY_TOMOYO
175 default DEFAULT_SECURITY_APPARMOR if SECURITY_APPARMOR
176 default DEFAULT_SECURITY_DAC
177
178 help
179 Select the security module that will be used by default if the
180 kernel parameter security= is not specified.
181
182 config DEFAULT_SECURITY_SELINUX
183 bool "SELinux" if SECURITY_SELINUX=y
184
185 config DEFAULT_SECURITY_SMACK
186 bool "Simplified Mandatory Access Control" if SECURITY_SMACK=y
187
188 config DEFAULT_SECURITY_TOMOYO
189 bool "TOMOYO" if SECURITY_TOMOYO=y
190
191 config DEFAULT_SECURITY_APPARMOR
192 bool "AppArmor" if SECURITY_APPARMOR=y
193
194 config DEFAULT_SECURITY_DAC
195 bool "Unix Discretionary Access Controls"
196
197endchoice
198
199config DEFAULT_SECURITY
200 string
201 default "selinux" if DEFAULT_SECURITY_SELINUX
202 default "smack" if DEFAULT_SECURITY_SMACK
203 default "tomoyo" if DEFAULT_SECURITY_TOMOYO
204 default "apparmor" if DEFAULT_SECURITY_APPARMOR
205 default "" if DEFAULT_SECURITY_DAC
206
207endmenu
208
209
