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