linux/Documentation
Mimi Zohar 398c42e2c4 ima: support fs-verity file digest based version 3 signatures
IMA may verify a file's integrity against a "good" value stored in the
'security.ima' xattr or as an appended signature, based on policy.  When
the "good value" is stored in the xattr, the xattr may contain a file
hash or signature.  In either case, the "good" value is preceded by a
header.  The first byte of the xattr header indicates the type of data
- hash, signature - stored in the xattr.  To support storing fs-verity
signatures in the 'security.ima' xattr requires further differentiating
the fs-verity signature from the existing IMA signature.

In addition the signatures stored in 'security.ima' xattr, need to be
disambiguated.  Instead of directly signing the fs-verity digest, a new
signature format version 3 is defined as the hash of the ima_file_id
structure, which identifies the type of signature and the digest.

The IMA policy defines "which" files are to be measured, verified, and/or
audited.  For those files being verified, the policy rules indicate "how"
the file should be verified.  For example to require a file be signed,
the appraise policy rule must include the 'appraise_type' option.

	appraise_type:= [imasig] | [imasig|modsig] | [sigv3]
           where 'imasig' is the original or signature format v2 (default),
           where 'modsig' is an appended signature,
           where 'sigv3' is the signature format v3.

The policy rule must also indicate the type of digest, if not the IMA
default, by first specifying the digest type:

	digest_type:= [verity]

The following policy rule requires fsverity signatures.  The rule may be
constrained, for example based on a fsuuid or LSM label.

      appraise func=BPRM_CHECK digest_type=verity appraise_type=sigv3

Acked-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2022-05-05 17:41:51 -04:00
..
ABI ima: support fs-verity file digest based version 3 signatures 2022-05-05 17:41:51 -04:00
accounting - A bunch of fixes: forced idle time accounting, utilization values 2022-01-23 17:35:27 +02:00
admin-guide ima: define a new template field named 'd-ngv2' and templates 2022-05-05 11:49:13 -04:00
arc
arm Documentation: arm: marvell: Extend Avanta list 2022-01-27 11:22:34 -07:00
arm64 Merge branch 'for-next/mte' into for-next/core 2022-03-14 19:01:23 +00:00
block block: remove biodoc.rst 2022-02-15 07:47:52 -07:00
bpf docs: netdev: move the netdev-FAQ to the process pages 2022-03-31 10:49:39 +02:00
cdrom Documentation: Fix links for udftools project and pktcdvd tool 2022-02-15 16:15:33 -07:00
core-api XArray update for 5.18: 2022-04-01 13:40:44 -07:00
cpu-freq cpufreq: Reintroduce ready() callback 2022-02-09 13:18:49 +05:30
crypto
dev-tools Some late-arriving documentation improvements. This is mostly build-system 2022-03-31 12:10:42 -07:00
devicetree dt-bindings: Fix phandle-array issues in the idle-states bindings 2022-04-01 15:09:50 -07:00
doc-guide
driver-api libnvdimm for 5.18 2022-03-30 10:04:11 -07:00
fault-injection
fb
features nds32: Remove the architecture 2022-03-07 13:54:59 +01:00
filesystems six ksmbd server fixes 2022-04-01 14:39:28 -07:00
firmware_class
firmware-guide Merge branch 'i2c/for-mergewindow' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2022-03-26 12:46:08 -07:00
fpga
gpu pci-v5.18-changes 2022-03-25 13:02:05 -07:00
hid
hwmon Char/Misc and other driver updates for 5.18-rc1 2022-03-28 12:27:35 -07:00
i2c i2c: i801: Add support for Intel Raptor Lake PCH-S 2022-02-15 10:03:40 +01:00
ia64
ide
iio
infiniband
input Input: docs: add more details on the use of BTN_TOOL 2022-03-01 15:46:03 +01:00
isdn
kbuild kbuild: Make $(LLVM) more flexible 2022-03-31 12:03:46 +09:00
kernel-hacking docs: fix typo in Documentation/kernel-hacking/locking.rst 2022-01-27 11:22:33 -07:00
leds
litmus-tests
livepatch
locking Documentation: Fix duplicate statement about raw_spinlock_t type 2022-03-25 13:30:08 -06:00
m68k
maintainer Some late-arriving documentation improvements. This is mostly build-system 2022-03-31 12:10:42 -07:00
mhi
mips
misc-devices
netlabel
networking docs: netdev: move the netdev-FAQ to the process pages 2022-03-31 10:49:39 +02:00
nios2
nvdimm
openrisc
parisc
PCI PCI/doc: cleanup references to the legacy PCI DMA API 2022-03-30 16:54:24 +02:00
pcmcia
peci docs: Add PECI documentation 2022-02-09 08:04:44 +01:00
power Documentation: EM: Describe new registration method using DT 2022-03-03 09:35:04 +05:30
powerpc
process docs: netdev: move the netdev-FAQ to the process pages 2022-03-31 10:49:39 +02:00
RCU
riscv Documentation: riscv: remove non-existent directory from table of contents 2022-03-31 16:18:56 -07:00
s390
scheduler Changes in this cycle were: 2022-03-22 14:39:12 -07:00
scsi scsi: ufs: docs: UFS documentation corrections 2022-03-08 22:49:49 -05:00
security ima: support fs-verity file digest based version 3 signatures 2022-05-05 17:41:51 -04:00
sh
sound ALSA: hda/realtek: Add alc256-samsung-headphone fixup 2022-03-22 21:51:02 +01:00
sparc
sphinx docs: sphinx/requirements: Limit jinja2<3.1 2022-03-30 13:44:54 -06:00
sphinx-static
spi spi: pxa2xx_spi: Convert to use GPIO descriptors 2022-01-31 15:17:27 +00:00
staging remoteproc: Change rproc_shutdown() to return a status 2022-03-11 14:31:55 -06:00
target
timers
tools Real Time Analysis Tool updates for 5.18 2022-03-23 11:08:10 -07:00
trace Updates to Tracing: 2022-04-03 12:26:01 -07:00
translations Kbuild -std=gnu11 updates for v5.18 2022-03-25 11:48:01 -07:00
tty
usb usb: gadget: f_uac2: Optionally determine bInterval for HS and SS 2022-01-31 14:26:18 +01:00
userspace-api platform-drivers-x86 for v5.18-1 2022-03-25 12:14:39 -07:00
virt * Only do MSR filtering for MSRs accessed by rdmsr/wrmsr 2022-04-02 12:09:02 -07:00
vm doc/vm/page_owner.rst: remove content related to -c option 2022-04-01 11:46:09 -07:00
w1
watchdog
x86 - More noinstr fixes 2022-03-25 12:34:53 -07:00
xtensa
.gitignore
arch.rst
asm-annotations.rst linkage: remove SYM_FUNC_{START,END}_ALIAS() 2022-02-22 16:21:34 +00:00
atomic_bitops.txt
atomic_t.txt
Changes
CodingStyle
conf.py docs: pdfdocs: Pull LaTeX preamble part out of conf.py 2022-02-24 12:26:13 -07:00
COPYING-logo
docutils.conf
dontdiff
index.rst docs: Add PECI documentation 2022-02-09 08:04:44 +01:00
Kconfig
logo.gif
Makefile docs: Makefile: Add -no-shell-escape option to LATEXOPTS 2022-02-14 12:50:17 -07:00
memory-barriers.txt
SubmittingPatches
watch_queue.rst