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 190source security/yama/Kconfig 191 192source security/integrity/Kconfig 193 194choice 195 prompt "Default security module" 196 default DEFAULT_SECURITY_SELINUX if SECURITY_SELINUX 197 default DEFAULT_SECURITY_SMACK if SECURITY_SMACK 198 default DEFAULT_SECURITY_TOMOYO if SECURITY_TOMOYO 199 default DEFAULT_SECURITY_APPARMOR if SECURITY_APPARMOR 200 default DEFAULT_SECURITY_YAMA if SECURITY_YAMA 201 default DEFAULT_SECURITY_DAC 202 203 help 204 Select the security module that will be used by default if the 205 kernel parameter security= is not specified. 206 207 config DEFAULT_SECURITY_SELINUX 208 bool "SELinux" if SECURITY_SELINUX=y 209 210 config DEFAULT_SECURITY_SMACK 211 bool "Simplified Mandatory Access Control" if SECURITY_SMACK=y 212 213 config DEFAULT_SECURITY_TOMOYO 214 bool "TOMOYO" if SECURITY_TOMOYO=y 215 216 config DEFAULT_SECURITY_APPARMOR 217 bool "AppArmor" if SECURITY_APPARMOR=y 218 219 config DEFAULT_SECURITY_YAMA 220 bool "Yama" if SECURITY_YAMA=y 221 222 config DEFAULT_SECURITY_DAC 223 bool "Unix Discretionary Access Controls" 224 225endchoice 226 227config DEFAULT_SECURITY 228 string 229 default "selinux" if DEFAULT_SECURITY_SELINUX 230 default "smack" if DEFAULT_SECURITY_SMACK 231 default "tomoyo" if DEFAULT_SECURITY_TOMOYO 232 default "apparmor" if DEFAULT_SECURITY_APPARMOR 233 default "yama" if DEFAULT_SECURITY_YAMA 234 default "" if DEFAULT_SECURITY_DAC 235 236endmenu 237 238