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