]>
Commit | Line | Data |
---|---|---|
1 | # | |
2 | # Security configuration | |
3 | # | |
4 | ||
5 | menu "Security options" | |
6 | ||
7 | source security/keys/Kconfig | |
8 | ||
9 | config 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 | ||
21 | config 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 | ||
34 | config SECURITY_WRITABLE_HOOKS | |
35 | depends on SECURITY | |
36 | bool | |
37 | default n | |
38 | ||
39 | config SECURITYFS | |
40 | bool "Enable the securityfs filesystem" | |
41 | help | |
42 | This will build the securityfs filesystem. It is currently used by | |
43 | the TPM bios character driver and IMA, an integrity provider. It is | |
44 | not used by SELinux or SMACK. | |
45 | ||
46 | If you are unsure how to answer this question, answer N. | |
47 | ||
48 | config SECURITY_NETWORK | |
49 | bool "Socket and Networking Security Hooks" | |
50 | depends on SECURITY | |
51 | help | |
52 | This enables the socket and networking security hooks. | |
53 | If enabled, a security module can use these hooks to | |
54 | implement socket and networking access controls. | |
55 | If you are unsure how to answer this question, answer N. | |
56 | ||
57 | config PAGE_TABLE_ISOLATION | |
58 | bool "Remove the kernel mapping in user mode" | |
59 | depends on X86_64 && !UML | |
60 | help | |
61 | This feature reduces the number of hardware side channels by | |
62 | ensuring that the majority of kernel addresses are not mapped | |
63 | into userspace. | |
64 | ||
65 | See Documentation/x86/pagetable-isolation.txt for more details. | |
66 | ||
67 | config SECURITY_INFINIBAND | |
68 | bool "Infiniband Security Hooks" | |
69 | depends on SECURITY && INFINIBAND | |
70 | help | |
71 | This enables the Infiniband security hooks. | |
72 | If enabled, a security module can use these hooks to | |
73 | implement Infiniband access controls. | |
74 | If you are unsure how to answer this question, answer N. | |
75 | ||
76 | config SECURITY_NETWORK_XFRM | |
77 | bool "XFRM (IPSec) Networking Security Hooks" | |
78 | depends on XFRM && SECURITY_NETWORK | |
79 | help | |
80 | This enables the XFRM (IPSec) networking security hooks. | |
81 | If enabled, a security module can use these hooks to | |
82 | implement per-packet access controls based on labels | |
83 | derived from IPSec policy. Non-IPSec communications are | |
84 | designated as unlabelled, and only sockets authorized | |
85 | to communicate unlabelled data can send without using | |
86 | IPSec. | |
87 | If you are unsure how to answer this question, answer N. | |
88 | ||
89 | config SECURITY_PATH | |
90 | bool "Security hooks for pathname based access control" | |
91 | depends on SECURITY | |
92 | help | |
93 | This enables the security hooks for pathname based access control. | |
94 | If enabled, a security module can use these hooks to | |
95 | implement pathname based access controls. | |
96 | If you are unsure how to answer this question, answer N. | |
97 | ||
98 | config INTEL_TXT | |
99 | bool "Enable Intel(R) Trusted Execution Technology (Intel(R) TXT)" | |
100 | depends on HAVE_INTEL_TXT | |
101 | help | |
102 | This option enables support for booting the kernel with the | |
103 | Trusted Boot (tboot) module. This will utilize | |
104 | Intel(R) Trusted Execution Technology to perform a measured launch | |
105 | of the kernel. If the system does not support Intel(R) TXT, this | |
106 | will have no effect. | |
107 | ||
108 | Intel TXT will provide higher assurance of system configuration and | |
109 | initial state as well as data reset protection. This is used to | |
110 | create a robust initial kernel measurement and verification, which | |
111 | helps to ensure that kernel security mechanisms are functioning | |
112 | correctly. This level of protection requires a root of trust outside | |
113 | of the kernel itself. | |
114 | ||
115 | Intel TXT also helps solve real end user concerns about having | |
116 | confidence that their hardware is running the VMM or kernel that | |
117 | it was configured with, especially since they may be responsible for | |
118 | providing such assurances to VMs and services running on it. | |
119 | ||
120 | See <http://www.intel.com/technology/security/> for more information | |
121 | about Intel(R) TXT. | |
122 | See <http://tboot.sourceforge.net> for more information about tboot. | |
123 | See Documentation/intel_txt.txt for a description of how to enable | |
124 | Intel TXT support in a kernel boot. | |
125 | ||
126 | If you are unsure as to whether this is required, answer N. | |
127 | ||
128 | config LSM_MMAP_MIN_ADDR | |
129 | int "Low address space for LSM to protect from user allocation" | |
130 | depends on SECURITY && SECURITY_SELINUX | |
131 | default 32768 if ARM || (ARM64 && COMPAT) | |
132 | default 65536 | |
133 | help | |
134 | This is the portion of low virtual memory which should be protected | |
135 | from userspace allocation. Keeping a user from writing to low pages | |
136 | can help reduce the impact of kernel NULL pointer bugs. | |
137 | ||
138 | For most ia64, ppc64 and x86 users with lots of address space | |
139 | a value of 65536 is reasonable and should cause no problems. | |
140 | On arm and other archs it should not be higher than 32768. | |
141 | Programs which use vm86 functionality or have some need to map | |
142 | this low address space will need the permission specific to the | |
143 | systems running LSM. | |
144 | ||
145 | config HAVE_HARDENED_USERCOPY_ALLOCATOR | |
146 | bool | |
147 | help | |
148 | The heap allocator implements __check_heap_object() for | |
149 | validating memory ranges against heap object sizes in | |
150 | support of CONFIG_HARDENED_USERCOPY. | |
151 | ||
152 | config HARDENED_USERCOPY | |
153 | bool "Harden memory copies between kernel and userspace" | |
154 | depends on HAVE_HARDENED_USERCOPY_ALLOCATOR | |
155 | select BUG | |
156 | help | |
157 | This option checks for obviously wrong memory regions when | |
158 | copying memory to/from the kernel (via copy_to_user() and | |
159 | copy_from_user() functions) by rejecting memory ranges that | |
160 | are larger than the specified heap object, span multiple | |
161 | separately allocated pages, are not on the process stack, | |
162 | or are part of the kernel text. This kills entire classes | |
163 | of heap overflow exploits and similar kernel memory exposures. | |
164 | ||
165 | config HARDENED_USERCOPY_PAGESPAN | |
166 | bool "Refuse to copy allocations that span multiple pages" | |
167 | depends on HARDENED_USERCOPY | |
168 | depends on EXPERT | |
169 | help | |
170 | When a multi-page allocation is done without __GFP_COMP, | |
171 | hardened usercopy will reject attempts to copy it. There are, | |
172 | however, several cases of this in the kernel that have not all | |
173 | been removed. This config is intended to be used only while | |
174 | trying to find such users. | |
175 | ||
176 | config FORTIFY_SOURCE | |
177 | bool "Harden common str/mem functions against buffer overflows" | |
178 | depends on ARCH_HAS_FORTIFY_SOURCE | |
179 | help | |
180 | Detect overflows of buffers in common string and memory functions | |
181 | where the compiler can determine and validate the buffer sizes. | |
182 | ||
183 | config STATIC_USERMODEHELPER | |
184 | bool "Force all usermode helper calls through a single binary" | |
185 | help | |
186 | By default, the kernel can call many different userspace | |
187 | binary programs through the "usermode helper" kernel | |
188 | interface. Some of these binaries are statically defined | |
189 | either in the kernel code itself, or as a kernel configuration | |
190 | option. However, some of these are dynamically created at | |
191 | runtime, or can be modified after the kernel has started up. | |
192 | To provide an additional layer of security, route all of these | |
193 | calls through a single executable that can not have its name | |
194 | changed. | |
195 | ||
196 | Note, it is up to this single binary to then call the relevant | |
197 | "real" usermode helper binary, based on the first argument | |
198 | passed to it. If desired, this program can filter and pick | |
199 | and choose what real programs are called. | |
200 | ||
201 | If you wish for all usermode helper programs are to be | |
202 | disabled, choose this option and then set | |
203 | STATIC_USERMODEHELPER_PATH to an empty string. | |
204 | ||
205 | config STATIC_USERMODEHELPER_PATH | |
206 | string "Path to the static usermode helper binary" | |
207 | depends on STATIC_USERMODEHELPER | |
208 | default "/sbin/usermode-helper" | |
209 | help | |
210 | The binary called by the kernel when any usermode helper | |
211 | program is wish to be run. The "real" application's name will | |
212 | be in the first argument passed to this program on the command | |
213 | line. | |
214 | ||
215 | If you wish for all usermode helper programs to be disabled, | |
216 | specify an empty string here (i.e. ""). | |
217 | ||
218 | source security/selinux/Kconfig | |
219 | source security/smack/Kconfig | |
220 | source security/tomoyo/Kconfig | |
221 | source security/apparmor/Kconfig | |
222 | source security/loadpin/Kconfig | |
223 | source security/yama/Kconfig | |
224 | ||
225 | source security/integrity/Kconfig | |
226 | ||
227 | choice | |
228 | prompt "Default security module" | |
229 | default DEFAULT_SECURITY_SELINUX if SECURITY_SELINUX | |
230 | default DEFAULT_SECURITY_SMACK if SECURITY_SMACK | |
231 | default DEFAULT_SECURITY_TOMOYO if SECURITY_TOMOYO | |
232 | default DEFAULT_SECURITY_APPARMOR if SECURITY_APPARMOR | |
233 | default DEFAULT_SECURITY_DAC | |
234 | ||
235 | help | |
236 | Select the security module that will be used by default if the | |
237 | kernel parameter security= is not specified. | |
238 | ||
239 | config DEFAULT_SECURITY_SELINUX | |
240 | bool "SELinux" if SECURITY_SELINUX=y | |
241 | ||
242 | config DEFAULT_SECURITY_SMACK | |
243 | bool "Simplified Mandatory Access Control" if SECURITY_SMACK=y | |
244 | ||
245 | config DEFAULT_SECURITY_TOMOYO | |
246 | bool "TOMOYO" if SECURITY_TOMOYO=y | |
247 | ||
248 | config DEFAULT_SECURITY_APPARMOR | |
249 | bool "AppArmor" if SECURITY_APPARMOR=y | |
250 | ||
251 | config DEFAULT_SECURITY_DAC | |
252 | bool "Unix Discretionary Access Controls" | |
253 | ||
254 | endchoice | |
255 | ||
256 | config DEFAULT_SECURITY | |
257 | string | |
258 | default "selinux" if DEFAULT_SECURITY_SELINUX | |
259 | default "smack" if DEFAULT_SECURITY_SMACK | |
260 | default "tomoyo" if DEFAULT_SECURITY_TOMOYO | |
261 | default "apparmor" if DEFAULT_SECURITY_APPARMOR | |
262 | default "" if DEFAULT_SECURITY_DAC | |
263 | ||
264 | endmenu | |
265 |