1 # SPDX-License-Identifier: GPL-2.0-only
2 # IBM Integrity Measurement Architecture
5 bool "Integrity Measurement Architecture(IMA)"
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
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.
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.
33 bool "Enable carrying the IMA measurement list across a soft boot"
34 depends on IMA && TCG_TPM && HAVE_IMA_KEXEC
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.
41 Depending on the IMA policy, the measurement list can grow to
44 config IMA_MEASURE_PCR_IDX
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.
56 depends on IMA && AUDIT && (SECURITY_SELINUX || SECURITY_SMACK || SECURITY_APPARMOR)
59 Disabling this option will disregard LSM based policy rules.
62 prompt "Default template"
63 default IMA_NG_TEMPLATE
66 Select the default IMA measurement template.
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.
75 config IMA_NG_TEMPLATE
76 bool "ima-ng (default)"
77 config IMA_SIG_TEMPLATE
81 config IMA_DEFAULT_TEMPLATE
84 default "ima-ng" if IMA_NG_TEMPLATE
85 default "ima-sig" if IMA_SIG_TEMPLATE
88 prompt "Default integrity hash algorithm"
89 default IMA_DEFAULT_HASH_SHA1
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.
97 config IMA_DEFAULT_HASH_SHA1
99 depends on CRYPTO_SHA1=y
101 config IMA_DEFAULT_HASH_SHA256
103 depends on CRYPTO_SHA256=y
105 config IMA_DEFAULT_HASH_SHA512
107 depends on CRYPTO_SHA512=y
109 config IMA_DEFAULT_HASH_WP512
111 depends on CRYPTO_WP512=y
113 config IMA_DEFAULT_HASH_SM3
115 depends on CRYPTO_SM3=y
118 config IMA_DEFAULT_HASH
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
127 config IMA_WRITE_POLICY
128 bool "Enable multiple writes to the IMA policy"
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.
138 config IMA_READ_POLICY
139 bool "Enable reading back the current IMA policy"
141 default y if IMA_WRITE_POLICY
142 default n if !IMA_WRITE_POLICY
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.
149 bool "Appraise integrity measurements"
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
159 For more information on integrity appraisal refer to:
160 <http://linux-ima.sourceforge.net>
163 config IMA_ARCH_POLICY
164 bool "Enable loading an IMA architecture specific policy"
165 depends on (KEXEC_SIG && IMA) || IMA_APPRAISE \
166 && INTEGRITY_ASYMMETRIC_KEYS
169 This option enables loading an IMA architecture specific policy
170 based on run time secure boot flags.
172 config IMA_APPRAISE_BUILD_POLICY
173 bool "IMA build time configured policy rules"
174 depends on IMA_APPRAISE && INTEGRITY_ASYMMETRIC_KEYS
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.
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.
187 config IMA_APPRAISE_REQUIRE_FIRMWARE_SIGS
188 bool "Appraise firmware signatures"
189 depends on IMA_APPRAISE_BUILD_POLICY
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.
197 config IMA_APPRAISE_REQUIRE_KEXEC_SIGS
198 bool "Appraise kexec kernel image signatures"
199 depends on IMA_APPRAISE_BUILD_POLICY
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
206 Kernel image signatures can not be verified by the original
207 kexec_load syscall. Enabling this rule will prevent its
210 config IMA_APPRAISE_REQUIRE_MODULE_SIGS
211 bool "Appraise kernel modules signatures"
212 depends on IMA_APPRAISE_BUILD_POLICY
215 Enabling this rule will require all kernel modules to be signed
216 and verified by a public key on the trusted IMA keyring.
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.
222 config IMA_APPRAISE_REQUIRE_POLICY_SIGS
223 bool "Appraise IMA policy signature"
224 depends on IMA_APPRAISE_BUILD_POLICY
227 Enabling this rule will require the IMA policy to be signed and
228 and verified by a key on the trusted IMA keyring.
230 config IMA_APPRAISE_BOOTPARAM
231 bool "ima_appraise boot parameter"
232 depends on IMA_APPRAISE
235 This option enables the different "ima_appraise=" modes
236 (eg. fix, log) from the boot command line.
238 config 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
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.
251 config 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
258 This option requires that all keys added to the .ima
259 keyring be signed by a key on the system trusted keyring.
261 This option is deprecated in favor of INTEGRITY_TRUSTED_KEYRING
263 config 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
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.
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.
280 config IMA_BLACKLIST_KEYRING
281 bool "Create IMA machine owner blacklist keyrings (EXPERIMENTAL)"
282 depends on SYSTEM_TRUSTED_KEYRING
283 depends on IMA_TRUSTED_KEYRING
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.
292 bool "Load X509 certificate onto the '.ima' trusted keyring"
293 depends on IMA_TRUSTED_KEYRING
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.
303 string "IMA X509 certificate path"
304 depends on IMA_LOAD_X509
305 default "/etc/keys/x509_ima.der"
307 This option defines IMA X509 certificate path.
309 config IMA_APPRAISE_SIGNED_INIT
310 bool "Require signed user-space initialization"
311 depends on IMA_LOAD_X509
314 This option requires user-space init to be signed.
316 config IMA_MEASURE_ASYMMETRIC_KEYS
319 depends on ASYMMETRIC_PUBLIC_KEY_SUBTYPE=y
322 config IMA_QUEUE_EARLY_BOOT_KEYS
324 depends on IMA_MEASURE_ASYMMETRIC_KEYS
325 depends on SYSTEM_TRUSTED_KEYRING
328 config IMA_SECURE_AND_OR_TRUSTED_BOOT
330 depends on IMA_ARCH_POLICY
332 This option is selected by architectures to enable secure and/or
333 trusted boot based on IMA runtime policies.