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# IBM Integrity Measurement Architecture
#
config IMA
bool "Integrity Measurement Architecture(IMA)"
depends on SECURITY
select INTEGRITY
select SECURITYFS
select CRYPTO
select CRYPTO_HMAC
select CRYPTO_MD5
select CRYPTO_SHA1
select CRYPTO_HASH_INFO
select TCG_TPM if HAS_IOMEM && !UML
select TCG_TIS if TCG_TPM && X86
select TCG_IBMVTPM if TCG_TPM && PPC64
help
The Trusted Computing Group(TCG) runtime Integrity
Measurement Architecture(IMA) maintains a list of hash
values of executables and other sensitive system files,
as they are read or executed. If an attacker manages
to change the contents of an important system file
being measured, we can tell.
If your system has a TPM chip, then IMA also maintains
an aggregate integrity value over this list inside the
TPM hardware, so that the TPM can prove to a third party
whether or not critical system files have been modified.
Read <http://www.usenix.org/events/sec04/tech/sailer.html>
to learn more about IMA.
If unsure, say N.
config IMA_MEASURE_PCR_IDX
int
depends on IMA
range 8 14
default 10
help
IMA_MEASURE_PCR_IDX determines the TPM PCR register index
that IMA uses to maintain the integrity aggregate of the
measurement list. If unsure, use the default 10.
config IMA_LSM_RULES
bool
depends on IMA && AUDIT && (SECURITY_SELINUX || SECURITY_SMACK)
default y
help
Disabling this option will disregard LSM based policy rules.
choice
prompt "Default template"
default IMA_NG_TEMPLATE
depends on IMA
help
Select the default IMA measurement template.
The original 'ima' measurement list template contains a
hash, defined as 20 bytes, and a null terminated pathname,
limited to 255 characters. The 'ima-ng' measurement list
template permits both larger hash digests and longer
pathnames.
config IMA_TEMPLATE
bool "ima"
config IMA_NG_TEMPLATE
bool "ima-ng (default)"
config IMA_SIG_TEMPLATE
bool "ima-sig"
endchoice
config IMA_DEFAULT_TEMPLATE
string
depends on IMA
default "ima" if IMA_TEMPLATE
default "ima-ng" if IMA_NG_TEMPLATE
default "ima-sig" if IMA_SIG_TEMPLATE
choice
prompt "Default integrity hash algorithm"
default IMA_DEFAULT_HASH_SHA1
depends on IMA
help
Select the default hash algorithm used for the measurement
list, integrity appraisal and audit log. The compiled default
hash algorithm can be overwritten using the kernel command
line 'ima_hash=' option.
config IMA_DEFAULT_HASH_SHA1
bool "SHA1 (default)"
depends on CRYPTO_SHA1
config IMA_DEFAULT_HASH_SHA256
bool "SHA256"
depends on CRYPTO_SHA256 && !IMA_TEMPLATE
config IMA_DEFAULT_HASH_SHA512
bool "SHA512"
depends on CRYPTO_SHA512 && !IMA_TEMPLATE
config IMA_DEFAULT_HASH_WP512
bool "WP512"
depends on CRYPTO_WP512 && !IMA_TEMPLATE
endchoice
config IMA_DEFAULT_HASH
string
depends on IMA
default "sha1" if IMA_DEFAULT_HASH_SHA1
default "sha256" if IMA_DEFAULT_HASH_SHA256
default "sha512" if IMA_DEFAULT_HASH_SHA512
default "wp512" if IMA_DEFAULT_HASH_WP512
config IMA_APPRAISE
bool "Appraise integrity measurements"
depends on IMA
default n
help
This option enables local measurement integrity appraisal.
It requires the system to be labeled with a security extended
attribute containing the file hash measurement. To protect
the security extended attributes from offline attack, enable
and configure EVM.
For more information on integrity appraisal refer to:
<http://linux-ima.sourceforge.net>
If unsure, say N.
config IMA_TRUSTED_KEYRING
bool "Require all keys on the _ima keyring be signed"
depends on IMA_APPRAISE && SYSTEM_TRUSTED_KEYRING
default y
help
This option requires that all keys added to the _ima
keyring be signed by a key on the system trusted keyring.
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