linux-stable.git/Documentation/security, branch linux-5.15.y

KEYS: trusted: allow use of kernel RNG for key material

2023-10-19T21:05:33+00:00

[ Upstream commit fcd7c26901c83681532c6daac599e53d4df11738 ]

The two existing trusted key sources don't make use of the kernel RNG,
but instead let the hardware doing the sealing/unsealing also
generate the random key material. However, both users and future
backends may want to place less trust into the quality of the trust
source's random number generator and instead reuse the kernel entropy
pool, which can be seeded from multiple entropy sources.

Make this possible by adding a new trusted.rng parameter,
that will force use of the kernel RNG. In its absence, it's up
to the trust source to decide, which random numbers to use,
maintaining the existing behavior.

Suggested-by: Jarkko Sakkinen 
Acked-by: Sumit Garg 
Acked-by: Pankaj Gupta 
Reviewed-by: David Gstir 
Reviewed-by: Pankaj Gupta 
Reviewed-by: Jarkko Sakkinen 
Tested-by: Pankaj Gupta 
Tested-by: Michael Walle  # on ls1028a (non-E and E)
Tested-by: John Ernberg  # iMX8QXP
Signed-off-by: Ahmad Fatoum 
Signed-off-by: Jarkko Sakkinen 
Stable-dep-of: 01bbafc63b65 ("KEYS: trusted: Remove redundant static calls usage")
Signed-off-by: Sasha Levin

Merge tag 'docs-5.14' of git://git.lwn.net/linux

2021-06-28T23:53:05+00:00

Pull documentation updates from Jonathan Corbet:
 "This was a reasonably active cycle for documentation; this includes:

   - Some kernel-doc cleanups. That script is still regex onslaught from
     hell, but it has gotten a little better.

   - Improvements to the checkpatch docs, which are also used by the
     tool itself.

   - A major update to the pathname lookup documentation.

   - Elimination of :doc: markup, since our automarkup magic can create
     references from filenames without all the extra noise.

   - The flurry of Chinese translation activity continues.

  Plus, of course, the usual collection of updates, typo fixes, and
  warning fixes"

* tag 'docs-5.14' of git://git.lwn.net/linux: (115 commits)
  docs: path-lookup: use bare function() rather than literals
  docs: path-lookup: update symlink description
  docs: path-lookup: update get_link() ->follow_link description
  docs: path-lookup: update WALK_GET, WALK_PUT desc
  docs: path-lookup: no get_link()
  docs: path-lookup: update i_op->put_link and cookie description
  docs: path-lookup: i_op->follow_link replaced with i_op->get_link
  docs: path-lookup: Add macro name to symlink limit description
  docs: path-lookup: remove filename_mountpoint
  docs: path-lookup: update do_last() part
  docs: path-lookup: update path_mountpoint() part
  docs: path-lookup: update path_to_nameidata() part
  docs: path-lookup: update follow_managed() part
  docs: Makefile: Use CONFIG_SHELL not SHELL
  docs: Take a little noise out of the build process
  docs: x86: avoid using ReST :doc:`foo` markup
  docs: virt: kvm: s390-pv-boot.rst: avoid using ReST :doc:`foo` markup
  docs: userspace-api: landlock.rst: avoid using ReST :doc:`foo` markup
  docs: trace: ftrace.rst: avoid using ReST :doc:`foo` markup
  docs: trace: coresight: coresight.rst: avoid using ReST :doc:`foo` markup
  ...

docs: security: landlock.rst: avoid using ReST :doc:`foo` markup

2021-06-17T19:24:39+00:00

The :doc:`foo` tag is auto-generated via automarkup.py.
So, use the filename at the sources, instead of :doc:`foo`.

Signed-off-by: Mauro Carvalho Chehab 
Link: https://lore.kernel.org/r/9174021ef2c87f395a4cc0895a4b2f7fd97db626.1623824363.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet

doc: Fix warning in Documentation/security/IMA-templates.rst

2021-06-08T20:29:10+00:00

This patch fixes the warning:

Documentation/security/IMA-templates.rst:81: WARNING: Inline
substitution_reference start-string without end-string.

Reported-by: Stephen Rothwell 
Signed-off-by: Roberto Sassu 
Signed-off-by: Mimi Zohar

ima: Define new template evm-sig

2021-06-03T14:02:37+00:00

With the recent introduction of the evmsig template field, remote verifiers
can obtain the EVM portable signature instead of the IMA signature, to
verify file metadata.

After introducing the new fields to include file metadata in the
measurement list, this patch finally defines the evm-sig template, whose
format is:

d-ng|n-ng|evmsig|xattrnames|xattrlengths|xattrvalues|iuid|igid|imode

xattrnames, xattrlengths and xattrvalues are populated only from defined
EVM protected xattrs, i.e. the ones that EVM considers to verify the
portable signature. xattrnames and xattrlengths are populated only if the
xattr is present.

xattrnames and xattrlengths are not necessary for verifying the EVM
portable signature, but they are included for completeness of information,
if a remote verifier wants to infer more from file metadata.

Signed-off-by: Roberto Sassu 
Signed-off-by: Mimi Zohar

ima: Define new template fields xattrnames, xattrlengths and xattrvalues

2021-06-02T22:56:13+00:00

This patch defines the new template fields xattrnames, xattrlengths and
xattrvalues, which contain respectively a list of xattr names (strings,
separated by |), lengths (u32, hex) and values (hex). If an xattr is not
present, the name and length are not displayed in the measurement list.

Reported-by: kernel test robot  (Missing prototype def)
Signed-off-by: Roberto Sassu 
Signed-off-by: Mimi Zohar

ima: Define new template field imode

2021-06-01T19:17:30+00:00

This patch defines the new template field imode, which includes the
inode mode. It can be used by a remote verifier to verify the EVM portable
signature, if it was included with the template fields sig or evmsig.

Signed-off-by: Roberto Sassu 
Signed-off-by: Mimi Zohar

ima: Define new template fields iuid and igid

2021-06-01T19:17:30+00:00

This patch defines the new template fields iuid and igid, which include
respectively the inode UID and GID. For idmapped mounts, still the original
UID and GID are provided.

These fields can be used to verify the EVM portable signature, if it was
included with the template fields sig or evmsig.

Signed-off-by: Roberto Sassu 
Acked-by: Christian Brauner 
Signed-off-by: Mimi Zohar

ima: Introduce template field evmsig and write to field sig as fallback

2021-06-01T16:30:51+00:00

With the patch to accept EVM portable signatures when the
appraise_type=imasig requirement is specified in the policy, appraisal can
be successfully done even if the file does not have an IMA signature.

However, remote attestation would not see that a different signature type
was used, as only IMA signatures can be included in the measurement list.
This patch solves the issue by introducing the new template field 'evmsig'
to show EVM portable signatures and by including its value in the existing
field 'sig' if the IMA signature is not found.

Suggested-by: Mimi Zohar 
Signed-off-by: Roberto Sassu 
Signed-off-by: Mimi Zohar

Documentation: drop optional BOMs

2021-05-10T21:17:34+00:00

A few of the Documentation .rst files begin with a Unicode
byte order mark (BOM). The BOM may signify endianess for
16-bit or 32-bit encodings or indicate that the text stream
is indeed Unicode. We don't need it for either of those uses.
It may also interfere with (confuse) some software.

Since we don't need it and its use is optional, just delete
the uses of it in Documentation/.

https://en.wikipedia.org/wiki/Byte_order_mark

Signed-off-by: Randy Dunlap 
Reviewed-by: Matthew Wilcox (Oracle) 
Reviewed-by: Greg Kroah-Hartman 
Cc: Mauro Carvalho Chehab 
Link: https://lore.kernel.org/r/20210506231907.14359-1-rdunlap@infradead.org
Signed-off-by: Jonathan Corbet