security/integrity/ima/Kconfig

   1 # IBM Integrity Measurement Architecture
   2 #
   3 config 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
  30 config 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
  40 config 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
  47 choice
  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"
  66 endchoice
  67
  68 config 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
  75 choice
  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
 100 endchoice
 101
 102 config 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
 110 config 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
 121 config 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
 131 config 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
 146 config 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
 158 config 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
 175 config 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
 186 config 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
 197 config 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
 204 config 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.