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