1# IBM Integrity Measurement Architecture 2# 3config IMA 4 bool "Integrity Measurement Architecture(IMA)" 5 select SECURITYFS 6 select CRYPTO 7 select CRYPTO_HMAC 8 select CRYPTO_MD5 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 help 16 The Trusted Computing Group(TCG) runtime Integrity 17 Measurement Architecture(IMA) maintains a list of hash 18 values of executables and other sensitive system files, 19 as they are read or executed. If an attacker manages 20 to change the contents of an important system file 21 being measured, we can tell. 22 23 If your system has a TPM chip, then IMA also maintains 24 an aggregate integrity value over this list inside the 25 TPM hardware, so that the TPM can prove to a third party 26 whether or not critical system files have been modified. 27 Read <http://www.usenix.org/events/sec04/tech/sailer.html> 28 to learn more about IMA. 29 If unsure, say N. 30 31config IMA_KEXEC 32 bool "Enable carrying the IMA measurement list across a soft boot" 33 depends on IMA && TCG_TPM && HAVE_IMA_KEXEC 34 default n 35 help 36 TPM PCRs are only reset on a hard reboot. In order to validate 37 a TPM's quote after a soft boot, the IMA measurement list of the 38 running kernel must be saved and restored on boot. 39 40 Depending on the IMA policy, the measurement list can grow to 41 be very large. 42 43config IMA_MEASURE_PCR_IDX 44 int 45 depends on IMA 46 range 8 14 47 default 10 48 help 49 IMA_MEASURE_PCR_IDX determines the TPM PCR register index 50 that IMA uses to maintain the integrity aggregate of the 51 measurement list. If unsure, use the default 10. 52 53config IMA_LSM_RULES 54 bool 55 depends on IMA && AUDIT && (SECURITY_SELINUX || SECURITY_SMACK) 56 default y 57 help 58 Disabling this option will disregard LSM based policy rules. 59 60choice 61 prompt "Default template" 62 default IMA_NG_TEMPLATE 63 depends on IMA 64 help 65 Select the default IMA measurement template. 66 67 The original 'ima' measurement list template contains a 68 hash, defined as 20 bytes, and a null terminated pathname, 69 limited to 255 characters. The 'ima-ng' measurement list 70 template permits both larger hash digests and longer 71 pathnames. 72 73 config IMA_TEMPLATE 74 bool "ima" 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" if IMA_TEMPLATE 85 default "ima-ng" if IMA_NG_TEMPLATE 86 default "ima-sig" if IMA_SIG_TEMPLATE 87 88choice 89 prompt "Default integrity hash algorithm" 90 default IMA_DEFAULT_HASH_SHA1 91 depends on IMA 92 help 93 Select the default hash algorithm used for the measurement 94 list, integrity appraisal and audit log. The compiled default 95 hash algorithm can be overwritten using the kernel command 96 line 'ima_hash=' option. 97 98 config IMA_DEFAULT_HASH_SHA1 99 bool "SHA1 (default)" 100 depends on CRYPTO_SHA1=y 101 102 config IMA_DEFAULT_HASH_SHA256 103 bool "SHA256" 104 depends on CRYPTO_SHA256=y && !IMA_TEMPLATE 105 106 config IMA_DEFAULT_HASH_SHA512 107 bool "SHA512" 108 depends on CRYPTO_SHA512=y && !IMA_TEMPLATE 109 110 config IMA_DEFAULT_HASH_WP512 111 bool "WP512" 112 depends on CRYPTO_WP512=y && !IMA_TEMPLATE 113endchoice 114 115config IMA_DEFAULT_HASH 116 string 117 depends on IMA 118 default "sha1" if IMA_DEFAULT_HASH_SHA1 119 default "sha256" if IMA_DEFAULT_HASH_SHA256 120 default "sha512" if IMA_DEFAULT_HASH_SHA512 121 default "wp512" if IMA_DEFAULT_HASH_WP512 122 123config IMA_WRITE_POLICY 124 bool "Enable multiple writes to the IMA policy" 125 depends on IMA 126 default n 127 help 128 IMA policy can now be updated multiple times. The new rules get 129 appended to the original policy. Have in mind that the rules are 130 scanned in FIFO order so be careful when you design and add new ones. 131 132 If unsure, say N. 133 134config IMA_READ_POLICY 135 bool "Enable reading back the current IMA policy" 136 depends on IMA 137 default y if IMA_WRITE_POLICY 138 default n if !IMA_WRITE_POLICY 139 help 140 It is often useful to be able to read back the IMA policy. It is 141 even more important after introducing CONFIG_IMA_WRITE_POLICY. 142 This option allows the root user to see the current policy rules. 143 144config IMA_APPRAISE 145 bool "Appraise integrity measurements" 146 depends on IMA 147 default n 148 help 149 This option enables local measurement integrity appraisal. 150 It requires the system to be labeled with a security extended 151 attribute containing the file hash measurement. To protect 152 the security extended attributes from offline attack, enable 153 and configure EVM. 154 155 For more information on integrity appraisal refer to: 156 <http://linux-ima.sourceforge.net> 157 If unsure, say N. 158 159config IMA_APPRAISE_BOOTPARAM 160 bool "ima_appraise boot parameter" 161 depends on IMA_APPRAISE 162 default y 163 help 164 This option enables the different "ima_appraise=" modes 165 (eg. fix, log) from the boot command line. 166 167config IMA_TRUSTED_KEYRING 168 bool "Require all keys on the .ima keyring be signed (deprecated)" 169 depends on IMA_APPRAISE && SYSTEM_TRUSTED_KEYRING 170 depends on INTEGRITY_ASYMMETRIC_KEYS 171 select INTEGRITY_TRUSTED_KEYRING 172 default y 173 help 174 This option requires that all keys added to the .ima 175 keyring be signed by a key on the system trusted keyring. 176 177 This option is deprecated in favor of INTEGRITY_TRUSTED_KEYRING 178 179config IMA_KEYRINGS_PERMIT_SIGNED_BY_BUILTIN_OR_SECONDARY 180 bool "Permit keys validly signed by a built-in or secondary CA cert (EXPERIMENTAL)" 181 depends on SYSTEM_TRUSTED_KEYRING 182 depends on SECONDARY_TRUSTED_KEYRING 183 depends on INTEGRITY_ASYMMETRIC_KEYS 184 select INTEGRITY_TRUSTED_KEYRING 185 default n 186 help 187 Keys may be added to the IMA or IMA blacklist keyrings, if the 188 key is validly signed by a CA cert in the system built-in or 189 secondary trusted keyrings. 190 191 Intermediate keys between those the kernel has compiled in and the 192 IMA keys to be added may be added to the system secondary keyring, 193 provided they are validly signed by a key already resident in the 194 built-in or secondary trusted keyrings. 195 196config IMA_BLACKLIST_KEYRING 197 bool "Create IMA machine owner blacklist keyrings (EXPERIMENTAL)" 198 depends on SYSTEM_TRUSTED_KEYRING 199 depends on IMA_TRUSTED_KEYRING 200 default n 201 help 202 This option creates an IMA blacklist keyring, which contains all 203 revoked IMA keys. It is consulted before any other keyring. If 204 the search is successful the requested operation is rejected and 205 an error is returned to the caller. 206 207config IMA_LOAD_X509 208 bool "Load X509 certificate onto the '.ima' trusted keyring" 209 depends on IMA_TRUSTED_KEYRING 210 default n 211 help 212 File signature verification is based on the public keys 213 loaded on the .ima trusted keyring. These public keys are 214 X509 certificates signed by a trusted key on the 215 .system keyring. This option enables X509 certificate 216 loading from the kernel onto the '.ima' trusted keyring. 217 218config IMA_X509_PATH 219 string "IMA X509 certificate path" 220 depends on IMA_LOAD_X509 221 default "/etc/keys/x509_ima.der" 222 help 223 This option defines IMA X509 certificate path. 224 225config IMA_APPRAISE_SIGNED_INIT 226 bool "Require signed user-space initialization" 227 depends on IMA_LOAD_X509 228 default n 229 help 230 This option requires user-space init to be signed. 231