1# SPDX-License-Identifier: GPL-2.0-only 2# IBM Integrity Measurement Architecture 3# 4config IMA 5 bool "Integrity Measurement Architecture(IMA)" 6 select SECURITYFS 7 select CRYPTO 8 select CRYPTO_HMAC 9 select CRYPTO_MD5 10 select CRYPTO_SHA1 11 select CRYPTO_HASH_INFO 12 select TCG_TPM if HAS_IOMEM && !UML 13 select TCG_TIS if TCG_TPM && X86 14 select TCG_CRB if TCG_TPM && ACPI 15 select TCG_IBMVTPM if TCG_TPM && PPC_PSERIES 16 select INTEGRITY_AUDIT if AUDIT 17 help 18 The Trusted Computing Group(TCG) runtime Integrity 19 Measurement Architecture(IMA) maintains a list of hash 20 values of executables and other sensitive system files, 21 as they are read or executed. If an attacker manages 22 to change the contents of an important system file 23 being measured, we can tell. 24 25 If your system has a TPM chip, then IMA also maintains 26 an aggregate integrity value over this list inside the 27 TPM hardware, so that the TPM can prove to a third party 28 whether or not critical system files have been modified. 29 Read <https://www.usenix.org/events/sec04/tech/sailer.html> 30 to learn more about IMA. 31 If unsure, say N. 32 33config IMA_KEXEC 34 bool "Enable carrying the IMA measurement list across a soft boot" 35 depends on IMA && TCG_TPM && HAVE_IMA_KEXEC 36 default n 37 help 38 TPM PCRs are only reset on a hard reboot. In order to validate 39 a TPM's quote after a soft boot, the IMA measurement list of the 40 running kernel must be saved and restored on boot. 41 42 Depending on the IMA policy, the measurement list can grow to 43 be very large. 44 45config IMA_MEASURE_PCR_IDX 46 int 47 depends on IMA 48 range 8 14 49 default 10 50 help 51 IMA_MEASURE_PCR_IDX determines the TPM PCR register index 52 that IMA uses to maintain the integrity aggregate of the 53 measurement list. If unsure, use the default 10. 54 55config IMA_LSM_RULES 56 bool 57 depends on IMA && AUDIT && (SECURITY_SELINUX || SECURITY_SMACK || SECURITY_APPARMOR) 58 default y 59 help 60 Disabling this option will disregard LSM based policy rules. 61 62choice 63 prompt "Default template" 64 default IMA_NG_TEMPLATE 65 depends on IMA 66 help 67 Select the default IMA measurement template. 68 69 The original 'ima' measurement list template contains a 70 hash, defined as 20 bytes, and a null terminated pathname, 71 limited to 255 characters. The 'ima-ng' measurement list 72 template permits both larger hash digests and longer 73 pathnames. 74 75 config IMA_TEMPLATE 76 bool "ima" 77 config IMA_NG_TEMPLATE 78 bool "ima-ng (default)" 79 config IMA_SIG_TEMPLATE 80 bool "ima-sig" 81endchoice 82 83config IMA_DEFAULT_TEMPLATE 84 string 85 depends on IMA 86 default "ima" if IMA_TEMPLATE 87 default "ima-ng" if IMA_NG_TEMPLATE 88 default "ima-sig" if IMA_SIG_TEMPLATE 89 90choice 91 prompt "Default integrity hash algorithm" 92 default IMA_DEFAULT_HASH_SHA1 93 depends on IMA 94 help 95 Select the default hash algorithm used for the measurement 96 list, integrity appraisal and audit log. The compiled default 97 hash algorithm can be overwritten using the kernel command 98 line 'ima_hash=' option. 99 100 config IMA_DEFAULT_HASH_SHA1 101 bool "SHA1 (default)" 102 depends on CRYPTO_SHA1=y 103 104 config IMA_DEFAULT_HASH_SHA256 105 bool "SHA256" 106 depends on CRYPTO_SHA256=y && !IMA_TEMPLATE 107 108 config IMA_DEFAULT_HASH_SHA512 109 bool "SHA512" 110 depends on CRYPTO_SHA512=y && !IMA_TEMPLATE 111 112 config IMA_DEFAULT_HASH_WP512 113 bool "WP512" 114 depends on CRYPTO_WP512=y && !IMA_TEMPLATE 115 116 config IMA_DEFAULT_HASH_SM3 117 bool "SM3" 118 depends on CRYPTO_SM3=y && !IMA_TEMPLATE 119endchoice 120 121config IMA_DEFAULT_HASH 122 string 123 depends on IMA 124 default "sha1" if IMA_DEFAULT_HASH_SHA1 125 default "sha256" if IMA_DEFAULT_HASH_SHA256 126 default "sha512" if IMA_DEFAULT_HASH_SHA512 127 default "wp512" if IMA_DEFAULT_HASH_WP512 128 default "sm3" if IMA_DEFAULT_HASH_SM3 129 130config IMA_WRITE_POLICY 131 bool "Enable multiple writes to the IMA policy" 132 depends on IMA 133 default n 134 help 135 IMA policy can now be updated multiple times. The new rules get 136 appended to the original policy. Have in mind that the rules are 137 scanned in FIFO order so be careful when you design and add new ones. 138 139 If unsure, say N. 140 141config IMA_READ_POLICY 142 bool "Enable reading back the current IMA policy" 143 depends on IMA 144 default y if IMA_WRITE_POLICY 145 default n if !IMA_WRITE_POLICY 146 help 147 It is often useful to be able to read back the IMA policy. It is 148 even more important after introducing CONFIG_IMA_WRITE_POLICY. 149 This option allows the root user to see the current policy rules. 150 151config IMA_APPRAISE 152 bool "Appraise integrity measurements" 153 depends on IMA 154 default n 155 help 156 This option enables local measurement integrity appraisal. 157 It requires the system to be labeled with a security extended 158 attribute containing the file hash measurement. To protect 159 the security extended attributes from offline attack, enable 160 and configure EVM. 161 162 For more information on integrity appraisal refer to: 163 <http://linux-ima.sourceforge.net> 164 If unsure, say N. 165 166config IMA_ARCH_POLICY 167 bool "Enable loading an IMA architecture specific policy" 168 depends on (KEXEC_SIG && IMA) || IMA_APPRAISE \ 169 && INTEGRITY_ASYMMETRIC_KEYS 170 default n 171 help 172 This option enables loading an IMA architecture specific policy 173 based on run time secure boot flags. 174 175config IMA_APPRAISE_BUILD_POLICY 176 bool "IMA build time configured policy rules" 177 depends on IMA_APPRAISE && INTEGRITY_ASYMMETRIC_KEYS 178 default n 179 help 180 This option defines an IMA appraisal policy at build time, which 181 is enforced at run time without having to specify a builtin 182 policy name on the boot command line. The build time appraisal 183 policy rules persist after loading a custom policy. 184 185 Depending on the rules configured, this policy may require kernel 186 modules, firmware, the kexec kernel image, and/or the IMA policy 187 to be signed. Unsigned files might prevent the system from 188 booting or applications from working properly. 189 190config IMA_APPRAISE_REQUIRE_FIRMWARE_SIGS 191 bool "Appraise firmware signatures" 192 depends on IMA_APPRAISE_BUILD_POLICY 193 default n 194 help 195 This option defines a policy requiring all firmware to be signed, 196 including the regulatory.db. If both this option and 197 CFG80211_REQUIRE_SIGNED_REGDB are enabled, then both signature 198 verification methods are necessary. 199 200config IMA_APPRAISE_REQUIRE_KEXEC_SIGS 201 bool "Appraise kexec kernel image signatures" 202 depends on IMA_APPRAISE_BUILD_POLICY 203 default n 204 help 205 Enabling this rule will require all kexec'ed kernel images to 206 be signed and verified by a public key on the trusted IMA 207 keyring. 208 209 Kernel image signatures can not be verified by the original 210 kexec_load syscall. Enabling this rule will prevent its 211 usage. 212 213config IMA_APPRAISE_REQUIRE_MODULE_SIGS 214 bool "Appraise kernel modules signatures" 215 depends on IMA_APPRAISE_BUILD_POLICY 216 default n 217 help 218 Enabling this rule will require all kernel modules to be signed 219 and verified by a public key on the trusted IMA keyring. 220 221 Kernel module signatures can only be verified by IMA-appraisal, 222 via the finit_module syscall. Enabling this rule will prevent 223 the usage of the init_module syscall. 224 225config IMA_APPRAISE_REQUIRE_POLICY_SIGS 226 bool "Appraise IMA policy signature" 227 depends on IMA_APPRAISE_BUILD_POLICY 228 default n 229 help 230 Enabling this rule will require the IMA policy to be signed and 231 and verified by a key on the trusted IMA keyring. 232 233config IMA_APPRAISE_BOOTPARAM 234 bool "ima_appraise boot parameter" 235 depends on IMA_APPRAISE 236 default y 237 help 238 This option enables the different "ima_appraise=" modes 239 (eg. fix, log) from the boot command line. 240 241config IMA_APPRAISE_MODSIG 242 bool "Support module-style signatures for appraisal" 243 depends on IMA_APPRAISE 244 depends on INTEGRITY_ASYMMETRIC_KEYS 245 select PKCS7_MESSAGE_PARSER 246 select MODULE_SIG_FORMAT 247 default n 248 help 249 Adds support for signatures appended to files. The format of the 250 appended signature is the same used for signed kernel modules. 251 The modsig keyword can be used in the IMA policy to allow a hook 252 to accept such signatures. 253 254config IMA_TRUSTED_KEYRING 255 bool "Require all keys on the .ima keyring be signed (deprecated)" 256 depends on IMA_APPRAISE && SYSTEM_TRUSTED_KEYRING 257 depends on INTEGRITY_ASYMMETRIC_KEYS 258 select INTEGRITY_TRUSTED_KEYRING 259 default y 260 help 261 This option requires that all keys added to the .ima 262 keyring be signed by a key on the system trusted keyring. 263 264 This option is deprecated in favor of INTEGRITY_TRUSTED_KEYRING 265 266config IMA_KEYRINGS_PERMIT_SIGNED_BY_BUILTIN_OR_SECONDARY 267 bool "Permit keys validly signed by a built-in or secondary CA cert (EXPERIMENTAL)" 268 depends on SYSTEM_TRUSTED_KEYRING 269 depends on SECONDARY_TRUSTED_KEYRING 270 depends on INTEGRITY_ASYMMETRIC_KEYS 271 select INTEGRITY_TRUSTED_KEYRING 272 default n 273 help 274 Keys may be added to the IMA or IMA blacklist keyrings, if the 275 key is validly signed by a CA cert in the system built-in or 276 secondary trusted keyrings. 277 278 Intermediate keys between those the kernel has compiled in and the 279 IMA keys to be added may be added to the system secondary keyring, 280 provided they are validly signed by a key already resident in the 281 built-in or secondary trusted keyrings. 282 283config IMA_BLACKLIST_KEYRING 284 bool "Create IMA machine owner blacklist keyrings (EXPERIMENTAL)" 285 depends on SYSTEM_TRUSTED_KEYRING 286 depends on IMA_TRUSTED_KEYRING 287 default n 288 help 289 This option creates an IMA blacklist keyring, which contains all 290 revoked IMA keys. It is consulted before any other keyring. If 291 the search is successful the requested operation is rejected and 292 an error is returned to the caller. 293 294config IMA_LOAD_X509 295 bool "Load X509 certificate onto the '.ima' trusted keyring" 296 depends on IMA_TRUSTED_KEYRING 297 default n 298 help 299 File signature verification is based on the public keys 300 loaded on the .ima trusted keyring. These public keys are 301 X509 certificates signed by a trusted key on the 302 .system keyring. This option enables X509 certificate 303 loading from the kernel onto the '.ima' trusted keyring. 304 305config IMA_X509_PATH 306 string "IMA X509 certificate path" 307 depends on IMA_LOAD_X509 308 default "/etc/keys/x509_ima.der" 309 help 310 This option defines IMA X509 certificate path. 311 312config IMA_APPRAISE_SIGNED_INIT 313 bool "Require signed user-space initialization" 314 depends on IMA_LOAD_X509 315 default n 316 help 317 This option requires user-space init to be signed. 318 319config IMA_MEASURE_ASYMMETRIC_KEYS 320 bool 321 depends on IMA 322 depends on ASYMMETRIC_PUBLIC_KEY_SUBTYPE=y 323 default y 324 325config IMA_QUEUE_EARLY_BOOT_KEYS 326 bool 327 depends on IMA_MEASURE_ASYMMETRIC_KEYS 328 depends on SYSTEM_TRUSTED_KEYRING 329 default y 330 331config IMA_SECURE_AND_OR_TRUSTED_BOOT 332 bool 333 depends on IMA_ARCH_POLICY 334 help 335 This option is selected by architectures to enable secure and/or 336 trusted boot based on IMA runtime policies. 337