1 # SPDX-License-Identifier: GPL-2.0-only 1 # SPDX-License-Identifier: GPL-2.0-only
2 # IBM Integrity Measurement Architecture 2 # IBM Integrity Measurement Architecture
3 # 3 #
4 config IMA 4 config IMA
5 bool "Integrity Measurement Architectu 5 bool "Integrity Measurement Architecture(IMA)"
6 select SECURITYFS 6 select SECURITYFS
7 select CRYPTO 7 select CRYPTO
8 select CRYPTO_HMAC 8 select CRYPTO_HMAC
9 select CRYPTO_SHA1 9 select CRYPTO_SHA1
10 select CRYPTO_HASH_INFO 10 select CRYPTO_HASH_INFO
11 select SECURITY_PATH <<
12 select TCG_TPM if HAS_IOMEM 11 select TCG_TPM if HAS_IOMEM
13 select TCG_TIS if TCG_TPM && X86 12 select TCG_TIS if TCG_TPM && X86
14 select TCG_CRB if TCG_TPM && ACPI 13 select TCG_CRB if TCG_TPM && ACPI
15 select TCG_IBMVTPM if TCG_TPM && PPC_P 14 select TCG_IBMVTPM if TCG_TPM && PPC_PSERIES
16 select INTEGRITY_AUDIT if AUDIT 15 select INTEGRITY_AUDIT if AUDIT
17 help 16 help
18 The Trusted Computing Group(TCG) run 17 The Trusted Computing Group(TCG) runtime Integrity
19 Measurement Architecture(IMA) mainta 18 Measurement Architecture(IMA) maintains a list of hash
20 values of executables and other sens 19 values of executables and other sensitive system files,
21 as they are read or executed. If an 20 as they are read or executed. If an attacker manages
22 to change the contents of an importa 21 to change the contents of an important system file
23 being measured, we can tell. 22 being measured, we can tell.
24 23
25 If your system has a TPM chip, then 24 If your system has a TPM chip, then IMA also maintains
26 an aggregate integrity value over th 25 an aggregate integrity value over this list inside the
27 TPM hardware, so that the TPM can pr 26 TPM hardware, so that the TPM can prove to a third party
28 whether or not critical system files 27 whether or not critical system files have been modified.
29 Read <https://www.usenix.org/events/ 28 Read <https://www.usenix.org/events/sec04/tech/sailer.html>
30 to learn more about IMA. 29 to learn more about IMA.
31 If unsure, say N. 30 If unsure, say N.
32 31
33 if IMA <<
34 <<
35 config IMA_KEXEC 32 config IMA_KEXEC
36 bool "Enable carrying the IMA measurem 33 bool "Enable carrying the IMA measurement list across a soft boot"
37 depends on TCG_TPM && HAVE_IMA_KEXEC !! 34 depends on IMA && TCG_TPM && HAVE_IMA_KEXEC
38 default n 35 default n
39 help 36 help
40 TPM PCRs are only reset on a hard r 37 TPM PCRs are only reset on a hard reboot. In order to validate
41 a TPM's quote after a soft boot, th 38 a TPM's quote after a soft boot, the IMA measurement list of the
42 running kernel must be saved and re 39 running kernel must be saved and restored on boot.
43 40
44 Depending on the IMA policy, the me 41 Depending on the IMA policy, the measurement list can grow to
45 be very large. 42 be very large.
46 43
47 config IMA_MEASURE_PCR_IDX 44 config IMA_MEASURE_PCR_IDX
48 int 45 int
>> 46 depends on IMA
49 range 8 14 47 range 8 14
50 default 10 48 default 10
51 help 49 help
52 IMA_MEASURE_PCR_IDX determines the T 50 IMA_MEASURE_PCR_IDX determines the TPM PCR register index
53 that IMA uses to maintain the integr 51 that IMA uses to maintain the integrity aggregate of the
54 measurement list. If unsure, use th 52 measurement list. If unsure, use the default 10.
55 53
56 config IMA_LSM_RULES 54 config IMA_LSM_RULES
57 bool 55 bool
58 depends on AUDIT && (SECURITY_SELINUX !! 56 depends on IMA && AUDIT && (SECURITY_SELINUX || SECURITY_SMACK || SECURITY_APPARMOR)
59 default y 57 default y
60 help 58 help
61 Disabling this option will disregard 59 Disabling this option will disregard LSM based policy rules.
62 60
63 choice 61 choice
64 prompt "Default template" 62 prompt "Default template"
65 default IMA_NG_TEMPLATE 63 default IMA_NG_TEMPLATE
>> 64 depends on IMA
66 help 65 help
67 Select the default IMA measurement t 66 Select the default IMA measurement template.
68 67
69 The original 'ima' measurement list 68 The original 'ima' measurement list template contains a
70 hash, defined as 20 bytes, and a nul 69 hash, defined as 20 bytes, and a null terminated pathname,
71 limited to 255 characters. The 'ima 70 limited to 255 characters. The 'ima-ng' measurement list
72 template permits both larger hash di 71 template permits both larger hash digests and longer
73 pathnames. The configured default te 72 pathnames. The configured default template can be replaced
74 by specifying "ima_template=" on the 73 by specifying "ima_template=" on the boot command line.
75 74
76 config IMA_NG_TEMPLATE 75 config IMA_NG_TEMPLATE
77 bool "ima-ng (default)" 76 bool "ima-ng (default)"
78 config IMA_SIG_TEMPLATE 77 config IMA_SIG_TEMPLATE
79 bool "ima-sig" 78 bool "ima-sig"
80 endchoice 79 endchoice
81 80
82 config IMA_DEFAULT_TEMPLATE 81 config IMA_DEFAULT_TEMPLATE
83 string 82 string
>> 83 depends on IMA
84 default "ima-ng" if IMA_NG_TEMPLATE 84 default "ima-ng" if IMA_NG_TEMPLATE
85 default "ima-sig" if IMA_SIG_TEMPLATE 85 default "ima-sig" if IMA_SIG_TEMPLATE
86 86
87 choice 87 choice
88 prompt "Default integrity hash algorit 88 prompt "Default integrity hash algorithm"
89 default IMA_DEFAULT_HASH_SHA1 89 default IMA_DEFAULT_HASH_SHA1
>> 90 depends on IMA
90 help 91 help
91 Select the default hash algorithm u 92 Select the default hash algorithm used for the measurement
92 list, integrity appraisal and audit 93 list, integrity appraisal and audit log. The compiled default
93 hash algorithm can be overwritten u 94 hash algorithm can be overwritten using the kernel command
94 line 'ima_hash=' option. 95 line 'ima_hash=' option.
95 96
96 config IMA_DEFAULT_HASH_SHA1 97 config IMA_DEFAULT_HASH_SHA1
97 bool "SHA1 (default)" 98 bool "SHA1 (default)"
98 depends on CRYPTO_SHA1=y 99 depends on CRYPTO_SHA1=y
99 100
100 config IMA_DEFAULT_HASH_SHA256 101 config IMA_DEFAULT_HASH_SHA256
101 bool "SHA256" 102 bool "SHA256"
102 depends on CRYPTO_SHA256=y 103 depends on CRYPTO_SHA256=y
103 104
104 config IMA_DEFAULT_HASH_SHA512 105 config IMA_DEFAULT_HASH_SHA512
105 bool "SHA512" 106 bool "SHA512"
106 depends on CRYPTO_SHA512=y 107 depends on CRYPTO_SHA512=y
107 108
108 config IMA_DEFAULT_HASH_WP512 109 config IMA_DEFAULT_HASH_WP512
109 bool "WP512" 110 bool "WP512"
110 depends on CRYPTO_WP512=y 111 depends on CRYPTO_WP512=y
111 112
112 config IMA_DEFAULT_HASH_SM3 113 config IMA_DEFAULT_HASH_SM3
113 bool "SM3" 114 bool "SM3"
114 depends on CRYPTO_SM3_GENERIC= 115 depends on CRYPTO_SM3_GENERIC=y
115 endchoice 116 endchoice
116 117
117 config IMA_DEFAULT_HASH 118 config IMA_DEFAULT_HASH
118 string 119 string
>> 120 depends on IMA
119 default "sha1" if IMA_DEFAULT_HASH_SHA 121 default "sha1" if IMA_DEFAULT_HASH_SHA1
120 default "sha256" if IMA_DEFAULT_HASH_S 122 default "sha256" if IMA_DEFAULT_HASH_SHA256
121 default "sha512" if IMA_DEFAULT_HASH_S 123 default "sha512" if IMA_DEFAULT_HASH_SHA512
122 default "wp512" if IMA_DEFAULT_HASH_WP 124 default "wp512" if IMA_DEFAULT_HASH_WP512
123 default "sm3" if IMA_DEFAULT_HASH_SM3 125 default "sm3" if IMA_DEFAULT_HASH_SM3
124 126
125 config IMA_WRITE_POLICY 127 config IMA_WRITE_POLICY
126 bool "Enable multiple writes to the IM 128 bool "Enable multiple writes to the IMA policy"
>> 129 depends on IMA
127 default n 130 default n
128 help 131 help
129 IMA policy can now be updated multip 132 IMA policy can now be updated multiple times. The new rules get
130 appended to the original policy. Ha 133 appended to the original policy. Have in mind that the rules are
131 scanned in FIFO order so be careful 134 scanned in FIFO order so be careful when you design and add new ones.
132 135
133 If unsure, say N. 136 If unsure, say N.
134 137
135 config IMA_READ_POLICY 138 config IMA_READ_POLICY
136 bool "Enable reading back the current 139 bool "Enable reading back the current IMA policy"
>> 140 depends on IMA
137 default y if IMA_WRITE_POLICY 141 default y if IMA_WRITE_POLICY
138 default n if !IMA_WRITE_POLICY 142 default n if !IMA_WRITE_POLICY
139 help 143 help
140 It is often useful to be able to re 144 It is often useful to be able to read back the IMA policy. It is
141 even more important after introduci 145 even more important after introducing CONFIG_IMA_WRITE_POLICY.
142 This option allows the root user to 146 This option allows the root user to see the current policy rules.
143 147
144 config IMA_APPRAISE 148 config IMA_APPRAISE
145 bool "Appraise integrity measurements" 149 bool "Appraise integrity measurements"
>> 150 depends on IMA
146 default n 151 default n
147 help 152 help
148 This option enables local measuremen 153 This option enables local measurement integrity appraisal.
149 It requires the system to be labeled 154 It requires the system to be labeled with a security extended
150 attribute containing the file hash m 155 attribute containing the file hash measurement. To protect
151 the security extended attributes fro 156 the security extended attributes from offline attack, enable
152 and configure EVM. 157 and configure EVM.
153 158
154 For more information on integrity ap 159 For more information on integrity appraisal refer to:
155 <http://linux-ima.sourceforge.net> 160 <http://linux-ima.sourceforge.net>
156 If unsure, say N. 161 If unsure, say N.
157 162
158 config IMA_ARCH_POLICY 163 config IMA_ARCH_POLICY
159 bool "Enable loading an IMA architectu 164 bool "Enable loading an IMA architecture specific policy"
160 depends on (KEXEC_SIG && IMA) || IMA_A 165 depends on (KEXEC_SIG && IMA) || IMA_APPRAISE \
161 && INTEGRITY_ASYMMETRIC_KEY 166 && INTEGRITY_ASYMMETRIC_KEYS
162 default n 167 default n
163 help 168 help
164 This option enables loading an IMA a 169 This option enables loading an IMA architecture specific policy
165 based on run time secure boot flags. 170 based on run time secure boot flags.
166 171
167 config IMA_APPRAISE_BUILD_POLICY 172 config IMA_APPRAISE_BUILD_POLICY
168 bool "IMA build time configured policy 173 bool "IMA build time configured policy rules"
169 depends on IMA_APPRAISE && INTEGRITY_A 174 depends on IMA_APPRAISE && INTEGRITY_ASYMMETRIC_KEYS
170 default n 175 default n
171 help 176 help
172 This option defines an IMA appraisal 177 This option defines an IMA appraisal policy at build time, which
173 is enforced at run time without havi 178 is enforced at run time without having to specify a builtin
174 policy name on the boot command line 179 policy name on the boot command line. The build time appraisal
175 policy rules persist after loading a 180 policy rules persist after loading a custom policy.
176 181
177 Depending on the rules configured, t 182 Depending on the rules configured, this policy may require kernel
178 modules, firmware, the kexec kernel 183 modules, firmware, the kexec kernel image, and/or the IMA policy
179 to be signed. Unsigned files might 184 to be signed. Unsigned files might prevent the system from
180 booting or applications from working 185 booting or applications from working properly.
181 186
182 config IMA_APPRAISE_REQUIRE_FIRMWARE_SIGS 187 config IMA_APPRAISE_REQUIRE_FIRMWARE_SIGS
183 bool "Appraise firmware signatures" 188 bool "Appraise firmware signatures"
184 depends on IMA_APPRAISE_BUILD_POLICY 189 depends on IMA_APPRAISE_BUILD_POLICY
185 default n 190 default n
186 help 191 help
187 This option defines a policy requiri 192 This option defines a policy requiring all firmware to be signed,
188 including the regulatory.db. If bot 193 including the regulatory.db. If both this option and
189 CFG80211_REQUIRE_SIGNED_REGDB are en 194 CFG80211_REQUIRE_SIGNED_REGDB are enabled, then both signature
190 verification methods are necessary. 195 verification methods are necessary.
191 196
192 config IMA_APPRAISE_REQUIRE_KEXEC_SIGS 197 config IMA_APPRAISE_REQUIRE_KEXEC_SIGS
193 bool "Appraise kexec kernel image sign 198 bool "Appraise kexec kernel image signatures"
194 depends on IMA_APPRAISE_BUILD_POLICY 199 depends on IMA_APPRAISE_BUILD_POLICY
195 default n 200 default n
196 help 201 help
197 Enabling this rule will require all 202 Enabling this rule will require all kexec'ed kernel images to
198 be signed and verified by a public k 203 be signed and verified by a public key on the trusted IMA
199 keyring. 204 keyring.
200 205
201 Kernel image signatures can not be v 206 Kernel image signatures can not be verified by the original
202 kexec_load syscall. Enabling this r 207 kexec_load syscall. Enabling this rule will prevent its
203 usage. 208 usage.
204 209
205 config IMA_APPRAISE_REQUIRE_MODULE_SIGS 210 config IMA_APPRAISE_REQUIRE_MODULE_SIGS
206 bool "Appraise kernel modules signatur 211 bool "Appraise kernel modules signatures"
207 depends on IMA_APPRAISE_BUILD_POLICY 212 depends on IMA_APPRAISE_BUILD_POLICY
208 default n 213 default n
209 help 214 help
210 Enabling this rule will require all 215 Enabling this rule will require all kernel modules to be signed
211 and verified by a public key on the 216 and verified by a public key on the trusted IMA keyring.
212 217
213 Kernel module signatures can only be 218 Kernel module signatures can only be verified by IMA-appraisal,
214 via the finit_module syscall. Enabli 219 via the finit_module syscall. Enabling this rule will prevent
215 the usage of the init_module syscall 220 the usage of the init_module syscall.
216 221
217 config IMA_APPRAISE_REQUIRE_POLICY_SIGS 222 config IMA_APPRAISE_REQUIRE_POLICY_SIGS
218 bool "Appraise IMA policy signature" 223 bool "Appraise IMA policy signature"
219 depends on IMA_APPRAISE_BUILD_POLICY 224 depends on IMA_APPRAISE_BUILD_POLICY
220 default n 225 default n
221 help 226 help
222 Enabling this rule will require the 227 Enabling this rule will require the IMA policy to be signed and
223 and verified by a key on the trusted 228 and verified by a key on the trusted IMA keyring.
224 229
225 config IMA_APPRAISE_BOOTPARAM 230 config IMA_APPRAISE_BOOTPARAM
226 bool "ima_appraise boot parameter" 231 bool "ima_appraise boot parameter"
227 depends on IMA_APPRAISE 232 depends on IMA_APPRAISE
228 default y 233 default y
229 help 234 help
230 This option enables the different "i 235 This option enables the different "ima_appraise=" modes
231 (eg. fix, log) from the boot command 236 (eg. fix, log) from the boot command line.
232 237
233 config IMA_APPRAISE_MODSIG 238 config IMA_APPRAISE_MODSIG
234 bool "Support module-style signatures 239 bool "Support module-style signatures for appraisal"
235 depends on IMA_APPRAISE 240 depends on IMA_APPRAISE
236 depends on INTEGRITY_ASYMMETRIC_KEYS 241 depends on INTEGRITY_ASYMMETRIC_KEYS
237 select PKCS7_MESSAGE_PARSER 242 select PKCS7_MESSAGE_PARSER
238 select MODULE_SIG_FORMAT 243 select MODULE_SIG_FORMAT
239 default n 244 default n
240 help 245 help
241 Adds support for signatures appende 246 Adds support for signatures appended to files. The format of the
242 appended signature is the same used 247 appended signature is the same used for signed kernel modules.
243 The modsig keyword can be used in t 248 The modsig keyword can be used in the IMA policy to allow a hook
244 to accept such signatures. 249 to accept such signatures.
245 250
246 config IMA_KEYRINGS_PERMIT_SIGNED_BY_BUILTIN_O 251 config IMA_KEYRINGS_PERMIT_SIGNED_BY_BUILTIN_OR_SECONDARY
247 bool "Permit keys validly signed by a !! 252 bool "Permit keys validly signed by a built-in or secondary CA cert (EXPERIMENTAL)"
248 depends on SYSTEM_TRUSTED_KEYRING 253 depends on SYSTEM_TRUSTED_KEYRING
249 depends on SECONDARY_TRUSTED_KEYRING 254 depends on SECONDARY_TRUSTED_KEYRING
250 depends on INTEGRITY_ASYMMETRIC_KEYS 255 depends on INTEGRITY_ASYMMETRIC_KEYS
251 select INTEGRITY_TRUSTED_KEYRING 256 select INTEGRITY_TRUSTED_KEYRING
252 default n 257 default n
253 help 258 help
254 Keys may be added to the IMA or IMA 259 Keys may be added to the IMA or IMA blacklist keyrings, if the
255 key is validly signed by a CA cert i !! 260 key is validly signed by a CA cert in the system built-in or
256 machine (if configured), or secondar !! 261 secondary trusted keyrings.
257 key must also have the digitalSignat <<
258 262
259 Intermediate keys between those the 263 Intermediate keys between those the kernel has compiled in and the
260 IMA keys to be added may be added to 264 IMA keys to be added may be added to the system secondary keyring,
261 provided they are validly signed by 265 provided they are validly signed by a key already resident in the
262 built-in, machine (if configured) or !! 266 built-in or secondary trusted keyrings.
263 267
264 config IMA_BLACKLIST_KEYRING 268 config IMA_BLACKLIST_KEYRING
265 bool "Create IMA machine owner blackli 269 bool "Create IMA machine owner blacklist keyrings (EXPERIMENTAL)"
266 depends on SYSTEM_TRUSTED_KEYRING 270 depends on SYSTEM_TRUSTED_KEYRING
267 depends on INTEGRITY_TRUSTED_KEYRING !! 271 depends on IMA_TRUSTED_KEYRING
268 default n 272 default n
269 help 273 help
270 This option creates an IMA blacklis 274 This option creates an IMA blacklist keyring, which contains all
271 revoked IMA keys. It is consulted 275 revoked IMA keys. It is consulted before any other keyring. If
272 the search is successful the reques 276 the search is successful the requested operation is rejected and
273 an error is returned to the caller. 277 an error is returned to the caller.
274 278
275 config IMA_LOAD_X509 279 config IMA_LOAD_X509
276 bool "Load X509 certificate onto the ' 280 bool "Load X509 certificate onto the '.ima' trusted keyring"
277 depends on INTEGRITY_TRUSTED_KEYRING !! 281 depends on IMA_TRUSTED_KEYRING
278 default n 282 default n
279 help 283 help
280 File signature verification is base 284 File signature verification is based on the public keys
281 loaded on the .ima trusted keyring. 285 loaded on the .ima trusted keyring. These public keys are
282 X509 certificates signed by a trust 286 X509 certificates signed by a trusted key on the
283 .system keyring. This option enabl 287 .system keyring. This option enables X509 certificate
284 loading from the kernel onto the '. 288 loading from the kernel onto the '.ima' trusted keyring.
285 289
286 config IMA_X509_PATH 290 config IMA_X509_PATH
287 string "IMA X509 certificate path" 291 string "IMA X509 certificate path"
288 depends on IMA_LOAD_X509 292 depends on IMA_LOAD_X509
289 default "/etc/keys/x509_ima.der" 293 default "/etc/keys/x509_ima.der"
290 help 294 help
291 This option defines IMA X509 certif 295 This option defines IMA X509 certificate path.
292 296
293 config IMA_APPRAISE_SIGNED_INIT 297 config IMA_APPRAISE_SIGNED_INIT
294 bool "Require signed user-space initia 298 bool "Require signed user-space initialization"
295 depends on IMA_LOAD_X509 299 depends on IMA_LOAD_X509
296 default n 300 default n
297 help 301 help
298 This option requires user-space ini 302 This option requires user-space init to be signed.
299 303
300 config IMA_MEASURE_ASYMMETRIC_KEYS 304 config IMA_MEASURE_ASYMMETRIC_KEYS
301 bool 305 bool
>> 306 depends on IMA
302 depends on ASYMMETRIC_PUBLIC_KEY_SUBTY 307 depends on ASYMMETRIC_PUBLIC_KEY_SUBTYPE=y
303 default y 308 default y
304 309
305 config IMA_QUEUE_EARLY_BOOT_KEYS 310 config IMA_QUEUE_EARLY_BOOT_KEYS
306 bool 311 bool
307 depends on IMA_MEASURE_ASYMMETRIC_KEYS 312 depends on IMA_MEASURE_ASYMMETRIC_KEYS
308 depends on SYSTEM_TRUSTED_KEYRING 313 depends on SYSTEM_TRUSTED_KEYRING
309 default y 314 default y
310 315
311 config IMA_SECURE_AND_OR_TRUSTED_BOOT 316 config IMA_SECURE_AND_OR_TRUSTED_BOOT
312 bool 317 bool
313 depends on IMA_ARCH_POLICY 318 depends on IMA_ARCH_POLICY
314 help 319 help
315 This option is selected by architect 320 This option is selected by architectures to enable secure and/or
316 trusted boot based on IMA runtime po 321 trusted boot based on IMA runtime policies.
317 322
318 config IMA_DISABLE_HTABLE 323 config IMA_DISABLE_HTABLE
319 bool "Disable htable to allow measurem 324 bool "Disable htable to allow measurement of duplicate records"
>> 325 depends on IMA
320 default n 326 default n
321 help 327 help
322 This option disables htable to allo 328 This option disables htable to allow measurement of duplicate records.
323 <<
324 endif <<
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