734114f878
Add the following:
(1) A new system keyring that is used to store information about
blacklisted certificates and signatures.
(2) A new key type (called 'blacklist') that is used to store a
blacklisted hash in its description as a hex string. The key accepts
no payload.
(3) The ability to configure a list of blacklisted hashes into the kernel
at build time. This is done by setting
CONFIG_SYSTEM_BLACKLIST_HASH_LIST to the filename of a list of hashes
that are in the form:
"<hash>", "<hash>", ..., "<hash>"
where each <hash> is a hex string representation of the hash and must
include all necessary leading zeros to pad the hash to the right size.
The above are enabled with CONFIG_SYSTEM_BLACKLIST_KEYRING.
Once the kernel is booted, the blacklist keyring can be listed:
root@andromeda ~]# keyctl show %:.blacklist
Keyring
723359729 ---lswrv 0 0 keyring: .blacklist
676257228 ---lswrv 0 0 \_ blacklist: 123412341234c55c1dcc601ab8e172917706aa32fb5eaf826813547fdf02dd46
The blacklist cannot currently be modified by userspace, but it will be
possible to load it, for example, from the UEFI blacklist database.
A later commit will make it possible to load blacklisted asymmetric keys in
here too.
Signed-off-by: David Howells <dhowells@redhat.com>
85 lines
3.4 KiB
Text
85 lines
3.4 KiB
Text
menu "Certificates for signature checking"
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config MODULE_SIG_KEY
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string "File name or PKCS#11 URI of module signing key"
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default "certs/signing_key.pem"
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depends on MODULE_SIG
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help
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Provide the file name of a private key/certificate in PEM format,
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or a PKCS#11 URI according to RFC7512. The file should contain, or
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the URI should identify, both the certificate and its corresponding
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private key.
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If this option is unchanged from its default "certs/signing_key.pem",
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then the kernel will automatically generate the private key and
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certificate as described in Documentation/module-signing.txt
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config SYSTEM_TRUSTED_KEYRING
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bool "Provide system-wide ring of trusted keys"
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depends on KEYS
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depends on ASYMMETRIC_KEY_TYPE
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help
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Provide a system keyring to which trusted keys can be added. Keys in
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the keyring are considered to be trusted. Keys may be added at will
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by the kernel from compiled-in data and from hardware key stores, but
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userspace may only add extra keys if those keys can be verified by
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keys already in the keyring.
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Keys in this keyring are used by module signature checking.
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config SYSTEM_TRUSTED_KEYS
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string "Additional X.509 keys for default system keyring"
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depends on SYSTEM_TRUSTED_KEYRING
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help
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If set, this option should be the filename of a PEM-formatted file
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containing trusted X.509 certificates to be included in the default
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system keyring. Any certificate used for module signing is implicitly
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also trusted.
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NOTE: If you previously provided keys for the system keyring in the
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form of DER-encoded *.x509 files in the top-level build directory,
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those are no longer used. You will need to set this option instead.
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config SYSTEM_EXTRA_CERTIFICATE
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bool "Reserve area for inserting a certificate without recompiling"
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depends on SYSTEM_TRUSTED_KEYRING
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help
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If set, space for an extra certificate will be reserved in the kernel
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image. This allows introducing a trusted certificate to the default
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system keyring without recompiling the kernel.
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config SYSTEM_EXTRA_CERTIFICATE_SIZE
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int "Number of bytes to reserve for the extra certificate"
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depends on SYSTEM_EXTRA_CERTIFICATE
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default 4096
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help
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This is the number of bytes reserved in the kernel image for a
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certificate to be inserted.
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config SECONDARY_TRUSTED_KEYRING
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bool "Provide a keyring to which extra trustable keys may be added"
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depends on SYSTEM_TRUSTED_KEYRING
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help
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If set, provide a keyring to which extra keys may be added, provided
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those keys are not blacklisted and are vouched for by a key built
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into the kernel or already in the secondary trusted keyring.
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config SYSTEM_BLACKLIST_KEYRING
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bool "Provide system-wide ring of blacklisted keys"
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depends on KEYS
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help
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Provide a system keyring to which blacklisted keys can be added.
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Keys in the keyring are considered entirely untrusted. Keys in this
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keyring are used by the module signature checking to reject loading
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of modules signed with a blacklisted key.
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config SYSTEM_BLACKLIST_HASH_LIST
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string "Hashes to be preloaded into the system blacklist keyring"
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depends on SYSTEM_BLACKLIST_KEYRING
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help
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If set, this option should be the filename of a list of hashes in the
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form "<hash>", "<hash>", ... . This will be included into a C
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wrapper to incorporate the list into the kernel. Each <hash> should
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be a string of hex digits.
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endmenu
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