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_SHA1 10 select CRYPTO_HASH_INFO 11 select TCG_TPM if HAS_IOMEM && !UML 12 select TCG_TIS if TCG_TPM && X86 13 select TCG_CRB if TCG_TPM && ACPI 14 select TCG_IBMVTPM if TCG_TPM && PPC_PSERIES 15 select INTEGRITY_AUDIT if AUDIT 16 help 17 The Trusted Computing Group(TCG) runtime Integrity 18 Measurement Architecture(IMA) maintains a list of hash 19 values of executables and other sensitive system files, 20 as they are read or executed. If an attacker manages 21 to change the contents of an important system file 22 being measured, we can tell. 23 24 If your system has a TPM chip, then IMA also maintains 25 an aggregate integrity value over this list inside the 26 TPM hardware, so that the TPM can prove to a third party 27 whether or not critical system files have been modified. 28 Read <https://www.usenix.org/events/sec04/tech/sailer.html> 29 to learn more about IMA. 30 If unsure, say N. 31 32config IMA_KEXEC 33 bool "Enable carrying the IMA measurement list across a soft boot" 34 depends on IMA && TCG_TPM && HAVE_IMA_KEXEC 35 default n 36 help 37 TPM PCRs are only reset on a hard reboot. In order to validate 38 a TPM's quote after a soft boot, the IMA measurement list of the 39 running kernel must be saved and restored on boot. 40 41 Depending on the IMA policy, the measurement list can grow to 42 be very large. 43 44config IMA_MEASURE_PCR_IDX 45 int 46 depends on IMA 47 range 8 14 48 default 10 49 help 50 IMA_MEASURE_PCR_IDX determines the TPM PCR register index 51 that IMA uses to maintain the integrity aggregate of the 52 measurement list. If unsure, use the default 10. 53 54config IMA_LSM_RULES 55 bool 56 depends on IMA && AUDIT && (SECURITY_SELINUX || SECURITY_SMACK || SECURITY_APPARMOR) 57 default y 58 help 59 Disabling this option will disregard LSM based policy rules. 60 61choice 62 prompt "Default template" 63 default IMA_NG_TEMPLATE 64 depends on IMA 65 help 66 Select the default IMA measurement template. 67 68 The original 'ima' measurement list template contains a 69 hash, defined as 20 bytes, and a null terminated pathname, 70 limited to 255 characters. The 'ima-ng' measurement list 71 template permits both larger hash digests and longer 72 pathnames. The configured default template can be replaced 73 by specifying "ima_template=" on the boot command line. 74 75 config IMA_NG_TEMPLATE 76 bool "ima-ng (default)" 77 config IMA_SIG_TEMPLATE 78 bool "ima-sig" 79endchoice 80 81config IMA_DEFAULT_TEMPLATE 82 string 83 depends on IMA 84 default "ima-ng" if IMA_NG_TEMPLATE 85 default "ima-sig" if IMA_SIG_TEMPLATE 86 87choice 88 prompt "Default integrity hash algorithm" 89 default IMA_DEFAULT_HASH_SHA1 90 depends on IMA 91 help 92 Select the default hash algorithm used for the measurement 93 list, integrity appraisal and audit log. The compiled default 94 hash algorithm can be overwritten using the kernel command 95 line 'ima_hash=' option. 96 97 config IMA_DEFAULT_HASH_SHA1 98 bool "SHA1 (default)" 99 depends on CRYPTO_SHA1=y 100 101 config IMA_DEFAULT_HASH_SHA256 102 bool "SHA256" 103 depends on CRYPTO_SHA256=y 104 105 config IMA_DEFAULT_HASH_SHA512 106 bool "SHA512" 107 depends on CRYPTO_SHA512=y 108 109 config IMA_DEFAULT_HASH_WP512 110 bool "WP512" 111 depends on CRYPTO_WP512=y 112 113 config IMA_DEFAULT_HASH_SM3 114 bool "SM3" 115 depends on CRYPTO_SM3=y 116endchoice 117 118config IMA_DEFAULT_HASH 119 string 120 depends on IMA 121 default "sha1" if IMA_DEFAULT_HASH_SHA1 122 default "sha256" if IMA_DEFAULT_HASH_SHA256 123 default "sha512" if IMA_DEFAULT_HASH_SHA512 124 default "wp512" if IMA_DEFAULT_HASH_WP512 125 default "sm3" if IMA_DEFAULT_HASH_SM3 126 127config IMA_WRITE_POLICY 128 bool "Enable multiple writes to the IMA policy" 129 depends on IMA 130 default n 131 help 132 IMA policy can now be updated multiple times. The new rules get 133 appended to the original policy. Have in mind that the rules are 134 scanned in FIFO order so be careful when you design and add new ones. 135 136 If unsure, say N. 137 138config IMA_READ_POLICY 139 bool "Enable reading back the current IMA policy" 140 depends on IMA 141 default y if IMA_WRITE_POLICY 142 default n if !IMA_WRITE_POLICY 143 help 144 It is often useful to be able to read back the IMA policy. It is 145 even more important after introducing CONFIG_IMA_WRITE_POLICY. 146 This option allows the root user to see the current policy rules. 147 148config IMA_APPRAISE 149 bool "Appraise integrity measurements" 150 depends on IMA 151 default n 152 help 153 This option enables local measurement integrity appraisal. 154 It requires the system to be labeled with a security extended 155 attribute containing the file hash measurement. To protect 156 the security extended attributes from offline attack, enable 157 and configure EVM. 158 159 For more information on integrity appraisal refer to: 160 <http://linux-ima.sourceforge.net> 161 If unsure, say N. 162 163config IMA_ARCH_POLICY 164 bool "Enable loading an IMA architecture specific policy" 165 depends on (KEXEC_SIG && IMA) || IMA_APPRAISE \ 166 && INTEGRITY_ASYMMETRIC_KEYS 167 default n 168 help 169 This option enables loading an IMA architecture specific policy 170 based on run time secure boot flags. 171 172config IMA_APPRAISE_BUILD_POLICY 173 bool "IMA build time configured policy rules" 174 depends on IMA_APPRAISE && INTEGRITY_ASYMMETRIC_KEYS 175 default n 176 help 177 This option defines an IMA appraisal policy at build time, which 178 is enforced at run time without having to specify a builtin 179 policy name on the boot command line. The build time appraisal 180 policy rules persist after loading a custom policy. 181 182 Depending on the rules configured, this policy may require kernel 183 modules, firmware, the kexec kernel image, and/or the IMA policy 184 to be signed. Unsigned files might prevent the system from 185 booting or applications from working properly. 186 187config IMA_APPRAISE_REQUIRE_FIRMWARE_SIGS 188 bool "Appraise firmware signatures" 189 depends on IMA_APPRAISE_BUILD_POLICY 190 default n 191 help 192 This option defines a policy requiring all firmware to be signed, 193 including the regulatory.db. If both this option and 194 CFG80211_REQUIRE_SIGNED_REGDB are enabled, then both signature 195 verification methods are necessary. 196 197config IMA_APPRAISE_REQUIRE_KEXEC_SIGS 198 bool "Appraise kexec kernel image signatures" 199 depends on IMA_APPRAISE_BUILD_POLICY 200 default n 201 help 202 Enabling this rule will require all kexec'ed kernel images to 203 be signed and verified by a public key on the trusted IMA 204 keyring. 205 206 Kernel image signatures can not be verified by the original 207 kexec_load syscall. Enabling this rule will prevent its 208 usage. 209 210config IMA_APPRAISE_REQUIRE_MODULE_SIGS 211 bool "Appraise kernel modules signatures" 212 depends on IMA_APPRAISE_BUILD_POLICY 213 default n 214 help 215 Enabling this rule will require all kernel modules to be signed 216 and verified by a public key on the trusted IMA keyring. 217 218 Kernel module signatures can only be verified by IMA-appraisal, 219 via the finit_module syscall. Enabling this rule will prevent 220 the usage of the init_module syscall. 221 222config IMA_APPRAISE_REQUIRE_POLICY_SIGS 223 bool "Appraise IMA policy signature" 224 depends on IMA_APPRAISE_BUILD_POLICY 225 default n 226 help 227 Enabling this rule will require the IMA policy to be signed and 228 and verified by a key on the trusted IMA keyring. 229 230config IMA_APPRAISE_BOOTPARAM 231 bool "ima_appraise boot parameter" 232 depends on IMA_APPRAISE 233 default y 234 help 235 This option enables the different "ima_appraise=" modes 236 (eg. fix, log) from the boot command line. 237 238config IMA_APPRAISE_MODSIG 239 bool "Support module-style signatures for appraisal" 240 depends on IMA_APPRAISE 241 depends on INTEGRITY_ASYMMETRIC_KEYS 242 select PKCS7_MESSAGE_PARSER 243 select MODULE_SIG_FORMAT 244 default n 245 help 246 Adds support for signatures appended to files. The format of the 247 appended signature is the same used for signed kernel modules. 248 The modsig keyword can be used in the IMA policy to allow a hook 249 to accept such signatures. 250 251config IMA_TRUSTED_KEYRING 252 bool "Require all keys on the .ima keyring be signed (deprecated)" 253 depends on IMA_APPRAISE && SYSTEM_TRUSTED_KEYRING 254 depends on INTEGRITY_ASYMMETRIC_KEYS 255 select INTEGRITY_TRUSTED_KEYRING 256 default y 257 help 258 This option requires that all keys added to the .ima 259 keyring be signed by a key on the system trusted keyring. 260 261 This option is deprecated in favor of INTEGRITY_TRUSTED_KEYRING 262 263config IMA_KEYRINGS_PERMIT_SIGNED_BY_BUILTIN_OR_SECONDARY 264 bool "Permit keys validly signed by a built-in or secondary CA cert (EXPERIMENTAL)" 265 depends on SYSTEM_TRUSTED_KEYRING 266 depends on SECONDARY_TRUSTED_KEYRING 267 depends on INTEGRITY_ASYMMETRIC_KEYS 268 select INTEGRITY_TRUSTED_KEYRING 269 default n 270 help 271 Keys may be added to the IMA or IMA blacklist keyrings, if the 272 key is validly signed by a CA cert in the system built-in or 273 secondary trusted keyrings. 274 275 Intermediate keys between those the kernel has compiled in and the 276 IMA keys to be added may be added to the system secondary keyring, 277 provided they are validly signed by a key already resident in the 278 built-in or secondary trusted keyrings. 279 280config IMA_BLACKLIST_KEYRING 281 bool "Create IMA machine owner blacklist keyrings (EXPERIMENTAL)" 282 depends on SYSTEM_TRUSTED_KEYRING 283 depends on IMA_TRUSTED_KEYRING 284 default n 285 help 286 This option creates an IMA blacklist keyring, which contains all 287 revoked IMA keys. It is consulted before any other keyring. If 288 the search is successful the requested operation is rejected and 289 an error is returned to the caller. 290 291config IMA_LOAD_X509 292 bool "Load X509 certificate onto the '.ima' trusted keyring" 293 depends on IMA_TRUSTED_KEYRING 294 default n 295 help 296 File signature verification is based on the public keys 297 loaded on the .ima trusted keyring. These public keys are 298 X509 certificates signed by a trusted key on the 299 .system keyring. This option enables X509 certificate 300 loading from the kernel onto the '.ima' trusted keyring. 301 302config IMA_X509_PATH 303 string "IMA X509 certificate path" 304 depends on IMA_LOAD_X509 305 default "/etc/keys/x509_ima.der" 306 help 307 This option defines IMA X509 certificate path. 308 309config IMA_APPRAISE_SIGNED_INIT 310 bool "Require signed user-space initialization" 311 depends on IMA_LOAD_X509 312 default n 313 help 314 This option requires user-space init to be signed. 315 316config IMA_MEASURE_ASYMMETRIC_KEYS 317 bool 318 depends on IMA 319 depends on ASYMMETRIC_PUBLIC_KEY_SUBTYPE=y 320 default y 321 322config IMA_QUEUE_EARLY_BOOT_KEYS 323 bool 324 depends on IMA_MEASURE_ASYMMETRIC_KEYS 325 depends on SYSTEM_TRUSTED_KEYRING 326 default y 327 328config IMA_SECURE_AND_OR_TRUSTED_BOOT 329 bool 330 depends on IMA_ARCH_POLICY 331 help 332 This option is selected by architectures to enable secure and/or 333 trusted boot based on IMA runtime policies. 334 335config IMA_DISABLE_HTABLE 336 bool "Disable htable to allow measurement of duplicate records" 337 depends on IMA 338 default n 339 help 340 This option disables htable to allow measurement of duplicate records. 341