21 May, 2019

1 commit


26 Apr, 2019

1 commit

  • Read the IPL Report block provided by secure-boot, add the entries
    of the certificate list to the system key ring and print the list
    of components.

    PR: Adjust to Vasilys bootdata_preserved patch set. Preserve ipl_cert_list
    for later use in kexec_file.

    Signed-off-by: Martin Schwidefsky
    Signed-off-by: Philipp Rudo
    Signed-off-by: Martin Schwidefsky

    Martin Schwidefsky
     

03 Jan, 2019

1 commit

  • …morris/linux-security

    Pull integrity updates from James Morris:
    "In Linux 4.19, a new LSM hook named security_kernel_load_data was
    upstreamed, allowing LSMs and IMA to prevent the kexec_load syscall.
    Different signature verification methods exist for verifying the
    kexec'ed kernel image. This adds additional support in IMA to prevent
    loading unsigned kernel images via the kexec_load syscall,
    independently of the IMA policy rules, based on the runtime "secure
    boot" flag. An initial IMA kselftest is included.

    In addition, this pull request defines a new, separate keyring named
    ".platform" for storing the preboot/firmware keys needed for verifying
    the kexec'ed kernel image's signature and includes the associated IMA
    kexec usage of the ".platform" keyring.

    (David Howell's and Josh Boyer's patches for reading the
    preboot/firmware keys, which were previously posted for a different
    use case scenario, are included here)"

    * 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
    integrity: Remove references to module keyring
    ima: Use inode_is_open_for_write
    ima: Support platform keyring for kernel appraisal
    efi: Allow the "db" UEFI variable to be suppressed
    efi: Import certificates from UEFI Secure Boot
    efi: Add an EFI signature blob parser
    efi: Add EFI signature data types
    integrity: Load certs to the platform keyring
    integrity: Define a trusted platform keyring
    selftests/ima: kexec_load syscall test
    ima: don't measure/appraise files on efivarfs
    x86/ima: retry detecting secure boot mode
    docs: Extend trusted keys documentation for TPM 2.0
    x86/ima: define arch_get_ima_policy() for x86
    ima: add support for arch specific policies
    ima: refactor ima_init_policy()
    ima: prevent kexec_load syscall based on runtime secureboot flag
    x86/ima: define arch_ima_get_secureboot
    integrity: support new struct public_key_signature encoding field

    Linus Torvalds
     

21 Dec, 2018

1 commit

  • The Kconfig lexer supports special characters such as '.' and '/' in
    the parameter context. In my understanding, the reason is just to
    support bare file paths in the source statement.

    I do not see a good reason to complicate Kconfig for the room of
    ambiguity.

    The majority of code already surrounds file paths with double quotes,
    and it makes sense since file paths are constant string literals.

    Make it treewide consistent now.

    Signed-off-by: Masahiro Yamada
    Acked-by: Wolfram Sang
    Acked-by: Geert Uytterhoeven
    Acked-by: Ingo Molnar

    Masahiro Yamada
     

13 Dec, 2018

1 commit

  • On secure boot enabled systems, a verified kernel may need to kexec
    additional kernels. For example, it may be used as a bootloader needing
    to kexec a target kernel or it may need to kexec a crashdump kernel. In
    such cases, it may want to verify the signature of the next kernel
    image.

    It is further possible that the kernel image is signed with third party
    keys which are stored as platform or firmware keys in the 'db' variable.
    The kernel, however, can not directly verify these platform keys, and an
    administrator may therefore not want to trust them for arbitrary usage.
    In order to differentiate platform keys from other keys and provide the
    necessary separation of trust, the kernel needs an additional keyring to
    store platform keys.

    This patch creates the new keyring called ".platform" to isolate keys
    provided by platform from keys by kernel. These keys are used to
    facilitate signature verification during kexec. Since the scope of this
    keyring is only the platform/firmware keys, it cannot be updated from
    userspace.

    This keyring can be enabled by setting CONFIG_INTEGRITY_PLATFORM_KEYRING.

    Signed-off-by: Nayna Jain
    Reviewed-by: Mimi Zohar
    Acked-by: Serge Hallyn
    Reviewed-by: James Morris
    Reviewed-by: Thiago Jung Bauermann
    Signed-off-by: Mimi Zohar

    Nayna Jain
     

13 Apr, 2016

1 commit


18 Feb, 2016

1 commit


10 Feb, 2016

1 commit

  • CONFIG_KEYS_DEBUG_PROC_KEYS is no longer an option as /proc/keys is now
    mandatory if the keyrings facility is enabled (it's used by libkeyutils in
    userspace).

    The defconfig references were removed with:

    perl -p -i -e 's/CONFIG_KEYS_DEBUG_PROC_KEYS=y\n//' \
    `git grep -l CONFIG_KEYS_DEBUG_PROC_KEYS=y`

    and the integrity Kconfig fixed by hand.

    Signed-off-by: David Howells
    cc: Andreas Ziegler
    cc: Dmitry Kasatkin

    David Howells
     

24 Nov, 2015

1 commit

  • Require all keys added to the EVM keyring be signed by an
    existing trusted key on the system trusted keyring.

    This patch also switches IMA to use integrity_init_keyring().

    Changes in v3:
    * Added 'init_keyring' config based variable to skip initializing
    keyring instead of using __integrity_init_keyring() wrapper.
    * Added dependency back to CONFIG_IMA_TRUSTED_KEYRING

    Changes in v2:
    * Replace CONFIG_EVM_TRUSTED_KEYRING with IMA and EVM common
    CONFIG_INTEGRITY_TRUSTED_KEYRING configuration option
    * Deprecate CONFIG_IMA_TRUSTED_KEYRING but keep it for config
    file compatibility. (Mimi Zohar)

    Signed-off-by: Dmitry Kasatkin
    Signed-off-by: Mimi Zohar

    Dmitry Kasatkin
     

07 Jan, 2015

1 commit


09 Sep, 2014

2 commits

  • The integrity subsystem has lots of options and takes more than
    half of the security menu. This patch consolidates the options
    under "integrity", which are hidden if not enabled. This change
    does not affect existing configurations. Re-configuration is not
    needed.

    Changes v4:
    - no need to change "integrity subsystem" to menuconfig as
    options are hidden, when not enabled. (Mimi)
    - add INTEGRITY Kconfig help description

    Changes v3:
    - dependency to INTEGRITY removed when behind 'if INTEGRITY'

    Changes v2:
    - previous patch moved integrity out of the 'security' menu.
    This version keeps integrity as a security option (Mimi).

    Signed-off-by: Dmitry Kasatkin
    Signed-off-by: Mimi Zohar

    Dmitry Kasatkin
     
  • For better visual appearance it is better to co-locate
    asymmetric key options together with signature support.

    Signed-off-by: Dmitry Kasatkin
    Signed-off-by: Mimi Zohar

    Dmitry Kasatkin
     

20 Jun, 2013

1 commit

  • This patch moves the integrity_audit_msg() function and defintion to
    security/integrity/, the parent directory, renames the 'ima_audit'
    boot command line option to 'integrity_audit', and fixes the Kconfig
    help text to reflect the actual code.

    Changelog:
    - Fixed ifdef inclusion of integrity_audit_msg() (Fengguang Wu)

    Signed-off-by: Mimi Zohar

    Mimi Zohar
     

07 Feb, 2013

1 commit

  • Asymmetric keys were introduced in linux-3.7 to verify the signature on
    signed kernel modules. The asymmetric keys infrastructure abstracts the
    signature verification from the crypto details. This patch adds IMA/EVM
    signature verification using asymmetric keys. Support for additional
    signature verification methods can now be delegated to the asymmetric
    key infrastructure.

    Although the module signature header and the IMA/EVM signature header
    could use the same format, to minimize the signature length and save
    space in the extended attribute, this patch defines a new IMA/EVM
    header format. The main difference is that the key identifier is a
    sha1[12 - 19] hash of the key modulus and exponent, similar to the
    current implementation. The only purpose of the key identifier is to
    identify the corresponding key in the kernel keyring. ima-evm-utils
    was updated to support the new signature format.

    While asymmetric signature verification functionality supports many
    different hash algorithms, the hash used in this patch is calculated
    during the IMA collection phase, based on the configured algorithm.
    The default algorithm is sha1, but for backwards compatibility md5
    is supported. Due to this current limitation, signatures should be
    generated using a sha1 hash algorithm.

    Changes in this patch:
    - Functionality has been moved to separate source file in order to get rid of
    in source #ifdefs.
    - keyid is derived according to the RFC 3280. It does not require to assign
    IMA/EVM specific "description" when loading X509 certificate. Kernel
    asymmetric key subsystem automatically generate the description. Also
    loading a certificate does not require using of ima-evm-utils and can be
    done using keyctl only.
    - keyid size is reduced to 32 bits to save xattr space. Key search is done
    using partial match functionality of asymmetric_key_match().
    - Kconfig option title was changed

    Signed-off-by: Dmitry Kasatkin
    Acked-by: David Howells
    Signed-off-by: Mimi Zohar

    Dmitry Kasatkin
     

18 Jan, 2012

2 commits


22 Nov, 2011

1 commit

  • Fix build errors by adding Kconfig dependency on KEYS.
    CRYPTO dependency removed.

    CC security/integrity/digsig.o
    security/integrity/digsig.c: In function ?integrity_digsig_verify?:
    security/integrity/digsig.c:38:4: error: implicit declaration of function ?request_key?
    security/integrity/digsig.c:38:17: error: ?key_type_keyring? undeclared (first use in this function)
    security/integrity/digsig.c:38:17: note: each undeclared identifier is reported only once for each function it appears in
    make[2]: *** [security/integrity/digsig.o] Error 1

    Reported-by: Randy Dunlap
    Signed-off-by: Dmitry Kasatkin
    Signed-off-by: James Morris

    Dmitry Kasatkin
     

09 Nov, 2011

1 commit


19 Jul, 2011

2 commits

  • EVM protects a file's security extended attributes(xattrs) against integrity
    attacks. This patchset provides the framework and an initial method. The
    initial method maintains an HMAC-sha1 value across the security extended
    attributes, storing the HMAC value as the extended attribute 'security.evm'.
    Other methods of validating the integrity of a file's metadata will be posted
    separately (eg. EVM-digital-signatures).

    While this patchset does authenticate the security xattrs, and
    cryptographically binds them to the inode, coming extensions will bind other
    directory and inode metadata for more complete protection. To help simplify
    the review and upstreaming process, each extension will be posted separately
    (eg. IMA-appraisal, IMA-appraisal-directory). For a general overview of the
    proposed Linux integrity subsystem, refer to Dave Safford's whitepaper:
    http://downloads.sf.net/project/linux-ima/linux-ima/Integrity_overview.pdf.

    EVM depends on the Kernel Key Retention System to provide it with a
    trusted/encrypted key for the HMAC-sha1 operation. The key is loaded onto the
    root's keyring using keyctl. Until EVM receives notification that the key has
    been successfully loaded onto the keyring (echo 1 > /evm), EVM can
    not create or validate the 'security.evm' xattr, but returns INTEGRITY_UNKNOWN.
    Loading the key and signaling EVM should be done as early as possible. Normally
    this is done in the initramfs, which has already been measured as part of the
    trusted boot. For more information on creating and loading existing
    trusted/encrypted keys, refer to Documentation/keys-trusted-encrypted.txt. A
    sample dracut patch, which loads the trusted/encrypted key and enables EVM, is
    available from http://linux-ima.sourceforge.net/#EVM.

    Based on the LSMs enabled, the set of EVM protected security xattrs is defined
    at compile. EVM adds the following three calls to the existing security hooks:
    evm_inode_setxattr(), evm_inode_post_setxattr(), and evm_inode_removexattr. To
    initialize and update the 'security.evm' extended attribute, EVM defines three
    calls: evm_inode_post_init(), evm_inode_post_setattr() and
    evm_inode_post_removexattr() hooks. To verify the integrity of a security
    xattr, EVM exports evm_verifyxattr().

    Changelog v7:
    - Fixed URL in EVM ABI documentation

    Changelog v6: (based on Serge Hallyn's review)
    - fix URL in patch description
    - remove evm_hmac_size definition
    - use SHA1_DIGEST_SIZE (removed both MAX_DIGEST_SIZE and evm_hmac_size)
    - moved linux include before other includes
    - test for crypto_hash_setkey failure
    - fail earlier for invalid key
    - clear entire encrypted key, even on failure
    - check xattr name length before comparing xattr names

    Changelog:
    - locking based on i_mutex, remove evm_mutex
    - using trusted/encrypted keys for storing the EVM key used in the HMAC-sha1
    operation.
    - replaced crypto hash with shash (Dmitry Kasatkin)
    - support for additional methods of verifying the security xattrs
    (Dmitry Kasatkin)
    - iint not allocated for all regular files, but only for those appraised
    - Use cap_sys_admin in lieu of cap_mac_admin
    - Use __vfs_setxattr_noperm(), without permission checks, from EVM

    Signed-off-by: Mimi Zohar
    Acked-by: Serge Hallyn

    Mimi Zohar
     
  • Move the inode integrity data(iint) management up to the integrity directory
    in order to share the iint among the different integrity models.

    Changelog:
    - don't define MAX_DIGEST_SIZE
    - rename several globally visible 'ima_' prefixed functions, structs,
    locks, etc to 'integrity_'
    - replace '20' with SHA1_DIGEST_SIZE
    - reflect location change in appropriate Kconfig and Makefiles
    - remove unnecessary initialization of iint_initialized to 0
    - rebased on current ima_iint.c
    - define integrity_iint_store/lock as static

    There should be no other functional changes.

    Signed-off-by: Mimi Zohar
    Acked-by: Serge Hallyn

    Mimi Zohar