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_IBMVTPM if TCG_TPM && PPC_PSERIES 14 help 15 The Trusted Computing Group(TCG) runtime Integrity 16 Measurement Architecture(IMA) maintains a list of hash 17 values of executables and other sensitive system files, 18 as they are read or executed. If an attacker manages 19 to change the contents of an important system file 20 being measured, we can tell. 21 22 If your system has a TPM chip, then IMA also maintains 23 an aggregate integrity value over this list inside the 24 TPM hardware, so that the TPM can prove to a third party 25 whether or not critical system files have been modified. 26 Read <http://www.usenix.org/events/sec04/tech/sailer.html> 27 to learn more about IMA. 28 If unsure, say N. 29 30config IMA_MEASURE_PCR_IDX 31 int 32 depends on IMA 33 range 8 14 34 default 10 35 help 36 IMA_MEASURE_PCR_IDX determines the TPM PCR register index 37 that IMA uses to maintain the integrity aggregate of the 38 measurement list. If unsure, use the default 10. 39 40config IMA_LSM_RULES 41 bool 42 depends on IMA && AUDIT && (SECURITY_SELINUX || SECURITY_SMACK) 43 default y 44 help 45 Disabling this option will disregard LSM based policy rules. 46 47choice 48 prompt "Default template" 49 default IMA_NG_TEMPLATE 50 depends on IMA 51 help 52 Select the default IMA measurement template. 53 54 The original 'ima' measurement list template contains a 55 hash, defined as 20 bytes, and a null terminated pathname, 56 limited to 255 characters. The 'ima-ng' measurement list 57 template permits both larger hash digests and longer 58 pathnames. 59 60 config IMA_TEMPLATE 61 bool "ima" 62 config IMA_NG_TEMPLATE 63 bool "ima-ng (default)" 64 config IMA_SIG_TEMPLATE 65 bool "ima-sig" 66endchoice 67 68config IMA_DEFAULT_TEMPLATE 69 string 70 depends on IMA 71 default "ima" if IMA_TEMPLATE 72 default "ima-ng" if IMA_NG_TEMPLATE 73 default "ima-sig" if IMA_SIG_TEMPLATE 74 75choice 76 prompt "Default integrity hash algorithm" 77 default IMA_DEFAULT_HASH_SHA1 78 depends on IMA 79 help 80 Select the default hash algorithm used for the measurement 81 list, integrity appraisal and audit log. The compiled default 82 hash algorithm can be overwritten using the kernel command 83 line 'ima_hash=' option. 84 85 config IMA_DEFAULT_HASH_SHA1 86 bool "SHA1 (default)" 87 depends on CRYPTO_SHA1 88 89 config IMA_DEFAULT_HASH_SHA256 90 bool "SHA256" 91 depends on CRYPTO_SHA256 && !IMA_TEMPLATE 92 93 config IMA_DEFAULT_HASH_SHA512 94 bool "SHA512" 95 depends on CRYPTO_SHA512 && !IMA_TEMPLATE 96 97 config IMA_DEFAULT_HASH_WP512 98 bool "WP512" 99 depends on CRYPTO_WP512 && !IMA_TEMPLATE 100endchoice 101 102config IMA_DEFAULT_HASH 103 string 104 depends on IMA 105 default "sha1" if IMA_DEFAULT_HASH_SHA1 106 default "sha256" if IMA_DEFAULT_HASH_SHA256 107 default "sha512" if IMA_DEFAULT_HASH_SHA512 108 default "wp512" if IMA_DEFAULT_HASH_WP512 109 110config IMA_WRITE_POLICY 111 bool "Enable multiple writes to the IMA policy" 112 depends on IMA 113 default n 114 help 115 IMA policy can now be updated multiple times. The new rules get 116 appended to the original policy. Have in mind that the rules are 117 scanned in FIFO order so be careful when you design and add new ones. 118 119 If unsure, say N. 120 121config IMA_READ_POLICY 122 bool "Enable reading back the current IMA policy" 123 depends on IMA 124 default y if IMA_WRITE_POLICY 125 default n if !IMA_WRITE_POLICY 126 help 127 It is often useful to be able to read back the IMA policy. It is 128 even more important after introducing CONFIG_IMA_WRITE_POLICY. 129 This option allows the root user to see the current policy rules. 130 131config IMA_APPRAISE 132 bool "Appraise integrity measurements" 133 depends on IMA 134 default n 135 help 136 This option enables local measurement integrity appraisal. 137 It requires the system to be labeled with a security extended 138 attribute containing the file hash measurement. To protect 139 the security extended attributes from offline attack, enable 140 and configure EVM. 141 142 For more information on integrity appraisal refer to: 143 <http://linux-ima.sourceforge.net> 144 If unsure, say N. 145 146config IMA_TRUSTED_KEYRING 147 bool "Require all keys on the .ima keyring be signed (deprecated)" 148 depends on IMA_APPRAISE && SYSTEM_TRUSTED_KEYRING 149 depends on INTEGRITY_ASYMMETRIC_KEYS 150 select INTEGRITY_TRUSTED_KEYRING 151 default y 152 help 153 This option requires that all keys added to the .ima 154 keyring be signed by a key on the system trusted keyring. 155 156 This option is deprecated in favor of INTEGRITY_TRUSTED_KEYRING 157 158config IMA_KEYRINGS_PERMIT_SIGNED_BY_BUILTIN_OR_SECONDARY 159 bool "Permit keys validly signed by a built-in or secondary CA cert (EXPERIMENTAL)" 160 depends on SYSTEM_TRUSTED_KEYRING 161 depends on SECONDARY_TRUSTED_KEYRING 162 depends on INTEGRITY_ASYMMETRIC_KEYS 163 select INTEGRITY_TRUSTED_KEYRING 164 default n 165 help 166 Keys may be added to the IMA or IMA blacklist keyrings, if the 167 key is validly signed by a CA cert in the system built-in or 168 secondary trusted keyrings. 169 170 Intermediate keys between those the kernel has compiled in and the 171 IMA keys to be added may be added to the system secondary keyring, 172 provided they are validly signed by a key already resident in the 173 built-in or secondary trusted keyrings. 174 175config IMA_BLACKLIST_KEYRING 176 bool "Create IMA machine owner blacklist keyrings (EXPERIMENTAL)" 177 depends on SYSTEM_TRUSTED_KEYRING 178 depends on IMA_TRUSTED_KEYRING 179 default n 180 help 181 This option creates an IMA blacklist keyring, which contains all 182 revoked IMA keys. It is consulted before any other keyring. If 183 the search is successful the requested operation is rejected and 184 an error is returned to the caller. 185 186config IMA_LOAD_X509 187 bool "Load X509 certificate onto the '.ima' trusted keyring" 188 depends on IMA_TRUSTED_KEYRING 189 default n 190 help 191 File signature verification is based on the public keys 192 loaded on the .ima trusted keyring. These public keys are 193 X509 certificates signed by a trusted key on the 194 .system keyring. This option enables X509 certificate 195 loading from the kernel onto the '.ima' trusted keyring. 196 197config IMA_X509_PATH 198 string "IMA X509 certificate path" 199 depends on IMA_LOAD_X509 200 default "/etc/keys/x509_ima.der" 201 help 202 This option defines IMA X509 certificate path. 203 204config IMA_APPRAISE_SIGNED_INIT 205 bool "Require signed user-space initialization" 206 depends on IMA_LOAD_X509 207 default n 208 help 209 This option requires user-space init to be signed. 210