10 Sep, 2018

1 commit

  • commit 817aef260037f33ee0f44c17fe341323d3aebd6d upstream.

    Replace the use of a magic number that indicates that verify_*_signature()
    should use the secondary keyring with a symbol.

    Signed-off-by: Yannik Sembritzki
    Signed-off-by: David Howells
    Cc: keyrings@vger.kernel.org
    Cc: linux-security-module@vger.kernel.org
    Signed-off-by: Linus Torvalds
    Signed-off-by: Greg Kroah-Hartman

    Yannik Sembritzki
     

02 Nov, 2017

1 commit

  • Many source files in the tree are missing licensing information, which
    makes it harder for compliance tools to determine the correct license.

    By default all files without license information are under the default
    license of the kernel, which is GPL version 2.

    Update the files which contain no license information with the 'GPL-2.0'
    SPDX license identifier. The SPDX identifier is a legally binding
    shorthand, which can be used instead of the full boiler plate text.

    This patch is based on work done by Thomas Gleixner and Kate Stewart and
    Philippe Ombredanne.

    How this work was done:

    Patches were generated and checked against linux-4.14-rc6 for a subset of
    the use cases:
    - file had no licensing information it it.
    - file was a */uapi/* one with no licensing information in it,
    - file was a */uapi/* one with existing licensing information,

    Further patches will be generated in subsequent months to fix up cases
    where non-standard license headers were used, and references to license
    had to be inferred by heuristics based on keywords.

    The analysis to determine which SPDX License Identifier to be applied to
    a file was done in a spreadsheet of side by side results from of the
    output of two independent scanners (ScanCode & Windriver) producing SPDX
    tag:value files created by Philippe Ombredanne. Philippe prepared the
    base worksheet, and did an initial spot review of a few 1000 files.

    The 4.13 kernel was the starting point of the analysis with 60,537 files
    assessed. Kate Stewart did a file by file comparison of the scanner
    results in the spreadsheet to determine which SPDX license identifier(s)
    to be applied to the file. She confirmed any determination that was not
    immediately clear with lawyers working with the Linux Foundation.

    Criteria used to select files for SPDX license identifier tagging was:
    - Files considered eligible had to be source code files.
    - Make and config files were included as candidates if they contained >5
    lines of source
    - File already had some variant of a license header in it (even if
    Reviewed-by: Philippe Ombredanne
    Reviewed-by: Thomas Gleixner
    Signed-off-by: Greg Kroah-Hartman

    Greg Kroah-Hartman
     

14 Jul, 2017

1 commit


09 May, 2017

1 commit

  • Fix typos and add the following to the scripts/spelling.txt:

    intialisation||initialisation
    intialised||initialised
    intialise||initialise

    This commit does not intend to change the British spelling itself.

    Link: http://lkml.kernel.org/r/1481573103-11329-18-git-send-email-yamada.masahiro@socionext.com
    Signed-off-by: Masahiro Yamada
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Masahiro Yamada
     

05 Apr, 2017

1 commit

  • Replace struct key's restrict_link function pointer with a pointer to
    the new struct key_restriction. The structure contains pointers to the
    restriction function as well as relevant data for evaluating the
    restriction.

    The garbage collector checks restrict_link->keytype when key types are
    unregistered. Restrictions involving a removed key type are converted
    to use restrict_link_reject so that restrictions cannot be removed by
    unregistering key types.

    Signed-off-by: Mat Martineau

    Mat Martineau
     

04 Apr, 2017

1 commit

  • The first argument to the restrict_link_func_t functions was a keyring
    pointer. These functions are called by the key subsystem with this
    argument set to the destination keyring, but restrict_link_by_signature
    expects a pointer to the relevant trusted keyring.

    Restrict functions may need something other than a single struct key
    pointer to allow or reject key linkage, so the data used to make that
    decision (such as the trust keyring) is moved to a new, fourth
    argument. The first argument is now always the destination keyring.

    Signed-off-by: Mat Martineau

    Mat Martineau
     

03 Apr, 2017

1 commit

  • 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:

    "", "", ..., ""

    where each 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

    David Howells
     

12 Apr, 2016

5 commits

  • Add a secondary system keyring that can be added to by root whilst the
    system is running - provided the key being added is vouched for by a key
    built into the kernel or already added to the secondary keyring.

    Rename .system_keyring to .builtin_trusted_keys to distinguish it more
    obviously from the new keyring (called .secondary_trusted_keys).

    The new keyring needs to be enabled with CONFIG_SECONDARY_TRUSTED_KEYRING.

    If the secondary keyring is enabled, a link is created from that to
    .builtin_trusted_keys so that the the latter will automatically be searched
    too if the secondary keyring is searched.

    Signed-off-by: David Howells

    David Howells
     
  • Remove KEY_FLAG_TRUSTED and KEY_ALLOC_TRUSTED as they're no longer
    meaningful. Also we can drop the trusted flag from the preparse structure.

    Given this, we no longer need to pass the key flags through to
    restrict_link().

    Further, we can now get rid of keyring_restrict_trusted_only() also.

    Signed-off-by: David Howells

    David Howells
     
  • Move the point at which a key is determined to be trustworthy to
    __key_link() so that we use the contents of the keyring being linked in to
    to determine whether the key being linked in is trusted or not.

    What is 'trusted' then becomes a matter of what's in the keyring.

    Currently, the test is done when the key is parsed, but given that at that
    point we can only sensibly refer to the contents of the system trusted
    keyring, we can only use that as the basis for working out the
    trustworthiness of a new key.

    With this change, a trusted keyring is a set of keys that once the
    trusted-only flag is set cannot be added to except by verification through
    one of the contained keys.

    Further, adding a key into a trusted keyring, whilst it might grant
    trustworthiness in the context of that keyring, does not automatically
    grant trustworthiness in the context of a second keyring to which it could
    be secondarily linked.

    To accomplish this, the authentication data associated with the key source
    must now be retained. For an X.509 cert, this means the contents of the
    AuthorityKeyIdentifier and the signature data.

    If system keyrings are disabled then restrict_link_by_builtin_trusted()
    resolves to restrict_link_reject(). The integrity digital signature code
    still works correctly with this as it was previously using
    KEY_FLAG_TRUSTED_ONLY, which doesn't permit anything to be added if there
    is no system keyring against which trust can be determined.

    Signed-off-by: David Howells

    David Howells
     
  • Make the system trusted keyring depend on the asymmetric key type as
    there's not a lot of point having it if you can't then load asymmetric keys
    onto it.

    This requires the ASYMMETRIC_KEY_TYPE to be made a bool, not a tristate, as
    the Kconfig language doesn't then correctly force ASYMMETRIC_KEY_TYPE to
    'y' rather than 'm' if SYSTEM_TRUSTED_KEYRING is 'y'.

    Making SYSTEM_TRUSTED_KEYRING *select* ASYMMETRIC_KEY_TYPE instead doesn't
    work as the Kconfig interpreter then wrongly complains about dependency
    loops.

    Signed-off-by: David Howells

    David Howells
     
  • Add a facility whereby proposed new links to be added to a keyring can be
    vetted, permitting them to be rejected if necessary. This can be used to
    block public keys from which the signature cannot be verified or for which
    the signature verification fails. It could also be used to provide
    blacklisting.

    This affects operations like add_key(), KEYCTL_LINK and KEYCTL_INSTANTIATE.

    To this end:

    (1) A function pointer is added to the key struct that, if set, points to
    the vetting function. This is called as:

    int (*restrict_link)(struct key *keyring,
    const struct key_type *key_type,
    unsigned long key_flags,
    const union key_payload *key_payload),

    where 'keyring' will be the keyring being added to, key_type and
    key_payload will describe the key being added and key_flags[*] can be
    AND'ed with KEY_FLAG_TRUSTED.

    [*] This parameter will be removed in a later patch when
    KEY_FLAG_TRUSTED is removed.

    The function should return 0 to allow the link to take place or an
    error (typically -ENOKEY, -ENOPKG or -EKEYREJECTED) to reject the
    link.

    The pointer should not be set directly, but rather should be set
    through keyring_alloc().

    Note that if called during add_key(), preparse is called before this
    method, but a key isn't actually allocated until after this function
    is called.

    (2) KEY_ALLOC_BYPASS_RESTRICTION is added. This can be passed to
    key_create_or_update() or key_instantiate_and_link() to bypass the
    restriction check.

    (3) KEY_FLAG_TRUSTED_ONLY is removed. The entire contents of a keyring
    with this restriction emplaced can be considered 'trustworthy' by
    virtue of being in the keyring when that keyring is consulted.

    (4) key_alloc() and keyring_alloc() take an extra argument that will be
    used to set restrict_link in the new key. This ensures that the
    pointer is set before the key is published, thus preventing a window
    of unrestrictedness. Normally this argument will be NULL.

    (5) As a temporary affair, keyring_restrict_trusted_only() is added. It
    should be passed to keyring_alloc() as the extra argument instead of
    setting KEY_FLAG_TRUSTED_ONLY on a keyring. This will be replaced in
    a later patch with functions that look in the appropriate places for
    authoritative keys.

    Signed-off-by: David Howells
    Reviewed-by: Mimi Zohar

    David Howells
     

06 Apr, 2016

2 commits

  • Make the determination of the trustworthiness of a key dependent on whether
    a key that can verify it is present in the supplied ring of trusted keys
    rather than whether or not the verifying key has KEY_FLAG_TRUSTED set.

    verify_pkcs7_signature() will return -ENOKEY if the PKCS#7 message trust
    chain cannot be verified.

    Signed-off-by: David Howells

    David Howells
     
  • Generalise system_verify_data() to provide access to internal content
    through a callback. This allows all the PKCS#7 stuff to be hidden inside
    this function and removed from the PE file parser and the PKCS#7 test key.

    If external content is not required, NULL should be passed as data to the
    function. If the callback is not required, that can be set to NULL.

    The function is now called verify_pkcs7_signature() to contrast with
    verify_pefile_signature() and the definitions of both have been moved into
    linux/verification.h along with the key_being_used_for enum.

    Signed-off-by: David Howells

    David Howells
     

29 Feb, 2016

1 commit


26 Feb, 2016

2 commits

  • Place a system_extra_cert buffer of configurable size, right after the
    system_certificate_list, so that inserted keys can be readily processed by
    the existing mechanism. Added script takes a key file and a kernel image
    and inserts its contents to the reserved area. The
    system_certificate_list_size is also adjusted accordingly.

    Call the script as:

    scripts/insert-sys-cert -b -c

    If vmlinux has no symbol table, supply System.map file with -s flag.
    Subsequent runs replace the previously inserted key, instead of appending
    the new one.

    Signed-off-by: Mehmet Kayaalp
    Signed-off-by: David Howells
    Acked-by: Mimi Zohar

    Mehmet Kayaalp
     
  • When a user calls 'make -s', we can assume they don't want to
    see any output except for warnings and errors, but instead
    they see this for a warning free build:

    ###
    ### Now generating an X.509 key pair to be used for signing modules.
    ###
    ### If this takes a long time, you might wish to run rngd in the
    ### background to keep the supply of entropy topped up. It
    ### needs to be run as root, and uses a hardware random
    ### number generator if one is available.
    ###
    Generating a 4096 bit RSA private key
    .................................................................................................................................................................................................................................++
    ..............................................................................................................................++
    writing new private key to 'certs/signing_key.pem'
    -----
    ###
    ### Key pair generated.
    ###

    The output can confuse simple build testing scripts that just check
    for an empty build log.

    This patch silences all the output:
    - "echo" is changed to "@$(kecho)", which is dropped when "-s" gets
    passed
    - the openssl command itself is only printed with V=1, using the
    $(Q) macro
    - The output of openssl gets redirected to /dev/null on "-s" builds.

    Signed-off-by: Arnd Bergmann
    Signed-off-by: David Howells

    Arnd Bergmann
     

10 Feb, 2016

1 commit


21 Oct, 2015

1 commit

  • Currently we see this in "git status" if we build in the source dir:

    Untracked files:
    (use "git add ..." to include in what will be committed)

    certs/x509_certificate_list

    It looks like it used to live in kernel/ so we squash that .gitignore
    entry at the same time. I didn't bother to dig through git history to
    see when it moved, since it is just a minor annoyance at most.

    Cc: David Woodhouse
    Cc: keyrings@linux-nfs.org
    Signed-off-by: Paul Gortmaker
    Signed-off-by: David Howells

    Paul Gortmaker
     

14 Aug, 2015

3 commits

  • Since commit 1329e8cc69 ("modsign: Extract signing cert from
    CONFIG_MODULE_SIG_KEY if needed"), the build system has carefully coped
    with the signing key being specified as a relative path in either the
    source or or the build trees.

    However, the actual signing of modules has not worked if the filename
    is relative to the source tree.

    Fix that by moving the config_filename helper into scripts/Kbuild.include
    so that it can be used from elsewhere, and then using it in the top-level
    Makefile to find the signing key file.

    Kill the intermediate $(MODPUBKEY) and $(MODSECKEY) variables too, while
    we're at it. There's no need for them.

    Signed-off-by: David Woodhouse
    Signed-off-by: David Howells

    David Woodhouse
     
  • We couldn't use if_changed for this before, because it didn't live in
    the kernel/ directory so we couldn't add it to $(targets). It was easier
    just to leave it as it was.

    Now it's in the certs/ directory we can use if_changed, the same as we
    do for the trusted certificate list.

    Aside from making things consistent, this means we don't need to depend
    explicitly on the include/config/module/sig/key.h file. And we also get
    to automatically do the right thing and re-extract the cert if the user
    does odd things like using a relative filename and then playing silly
    buggers with adding/removing that file in both the source and object
    trees. We always favour the one in the object tree if it exists, and
    now we'll correctly re-extract the cert when it changes. Previously we'd
    *only* re-extract the cert if the config option changed, even if the
    actual file we're using did change.

    Signed-off-by: David Woodhouse
    Signed-off-by: David Howells

    David Woodhouse
     
  • Move certificate handling out of the kernel/ directory and into a certs/
    directory to get all the weird stuff in one place and move the generated
    signing keys into this directory.

    Signed-off-by: David Howells
    Reviewed-by: David Woodhouse

    David Howells