When key_file is passed along with tpm2-device= to systemd-cryptsetup, the
logic is to try the blob as a TPM blob first, and then fall back to trying the
file as a regular key file. Check that this fallback works.
When a keyfile is passed with tpm2-device=, e.g.,
systemd-cryptsetup attach test_data /vol /my-pass tpm2-device=auto
the logic in attach_luks_or_plain_or_bitlk_by_tpm2() tries to process it as a
TPM blob first. This did not work properly because it passes n_blobs=1 to
acquire_tpm2_key(), and the key_file is only read when n_blobs == 0. As a
result, the code ends up calling tpm2_unseal(..., blobs=NULL, n_blobs=1, ...).
Before commit 5c6aad9 ("cryptsetup-tokens: Print tpm2-primary-alg: only when it
is known"), the segfault was not observed because tpm2_unseal() was bailing out
early when primary_alg == 0. However, after that change, it attempts to process
the blob (which is NULL) and crashes.
Fix this logic by passing n_blobs=0 to acquire_tpm2_key() so that it actually
reads the key_file. Additionally, assert 'blobs' in tpm2_unseal() as a
safeguard.
Fixes#41867
While it is possible to disable sysext/confext merging in the main system
with 'systemctl disable', sysext/confext are always merged in the initrd,
both by systemd-{sys,conf}ext-initrd.service and by
systemd-{sys,conf}ext-sysroot.service and especially the latter can be
unexpected. Provide kernel cmdline options systemd.{sys,conf}ext=0 and
rd.systemd.{sys,conf}ext=0 covering all options.
The new services are used to activate system and configuration extensions
for the main system from the initrd, this allows to overcome the limitation
that sysext/confext cannot be used to update the resources which are required
in the earliest boot of the system (before systemd-sysext/systemd-confext
start).
tpm_log_tagged_event() only measures the event to the TPM while
tpm_log_ipl_event() measures the event both to the TPM and CC. Fix the
inconsistency.
Note, this is a potentially breaking change for TDX guests as systemd will
now measure more stuff to the MRTD/RTMRs, reference values for attestation may
need to be adjusted.
Found by Claude Code Review.
When 'tpm2-primary-alg' is missing in LUKS JSON token, the output of
'cryptsetup luksDump' is always:
tpm2-primary-alg: ecc
because tpm2_parse_luks2_json() returns the default (TPM2_ALG_ECC). This can be
misleading and wrong. Make tpm2_parse_luks2_json() return the reality and move
the default to tpm2_unseal().
'tpm2-primary-alg' field is currently unset in LUKS JSON token both for the
case when SRK was used for enrolling (--tpm2-device-key=) and for the case when
SRK was obtained/generated (--tpm2-device=). While this information is not
really needed for unsealing (the sealed object itself has key type in it), it
may be convenient to see key type in e.g. 'cryptsetup luksDump' in the
situations where key type matters. Since 'tpm2-primary-alg' is already defined,
just set it properly in all cases.
Commit 15b1c33 ("repart: Generate fstab and crypttab late") moved
fstab/crypttab generation to the late stage but this introduced a regression:
it may be necessary to include fstab and crypttab into the generated partition
(e.g. with CopyFiles=). This is incompatible with 'fixate-volume-key' option as
it is impossible to capture LUKS volume key before it gets created but all the
rest should work fine.
Generate crypttab twice: early and late to capture possible changes. There's no
need to do the same for fstab for now, so keep the status quo.
The test checks that the expected hash is correctly recorded to the
generated crypttab and also checks that systemd-cryptsetup handles
the option correctly.
The expected hash (SHA265 HMAC signature) uses the exact same algorithm which
is used to calculate sha256 PCR bank digest when 'tpm2-measure-pcr=' is used.
tpm2_pcr_extend_bytes() has differences in parameter names between the
declaration and the implementation, in particular, 'event' in the header is
named 'event_type' in the implementation.
The immediate need for the change is to allow to capture the expected
LUKS volume key hash and record it to the generated crypttab but it
also seems to make sense to not generate crypttab/fstab before we know
that partition creation succeeded as fstab/crypttab entries are bogus
otherwise.
LUKS2 supports built-in integrity checking which may come very handy to
mitigate partial rollback attacks on the storage when only some specific
parts are restored to some old encrypted state. Specific use-cases like
Confidential VMs may want to mandate the usage of feature e.g. on the root
volume. Introduce "encryptedwithintegrity" image policy to support that.
Note, due to the current libcryptsetup limitations, checking whether the
feature is enabled or not for the 'file' case (e.g. DDI image as a raw file)
requires setting up a loop device. To avoid that and keep dissect fully
functional when working unpriviliged, implement a minimal custom LUKS header
parser.
Authenticated disk encryption is experimentally supported by cryptsetup since
v2.0.0 and allows for automatic dm-integrity setup for LUKS devices. Add
support for the mode to systemd-repart. Currently, the option can only be used
in 'online' mode as libcryptsetup does not support creating integrity data
without the use of in-kernel dm-integrity infrastructure.
Integrity=/IntegrityAlgorithm= are added in the anticipation of other integrity
protection options, e.g. enabling dm-integrity for a plain unencrypted
partition.
Load global sysext/confext from /.extra/global_{sysext,confext} which
systemd-stub puts there from ESP/loader/credentials/*.{sysext,confext}.raw.
Global extensions are handled the exact same way as per-UKI ones.
Systemd-stub support loading addons, credentials, system and configuration
extensions from ESP and while addons and credentials can be both global and
per-UKI, sysext/confext are only per-UKI.
Add support for loading ESP/loader/credentials/*.{sysext,confext}.raw to
systemd-stub.
Note: for backwards compatibility reasons, per-UKI sysexts can also be
*.raw (not only *.sysext.raw) but as global extensions are new, there's
no need to bring this legacy there.
ephemeral/ephemeral-import are described as possible '--mutable' options but
not present in the list. Note, "systemd-sysext --help" lists them correctly.
Commit 201e0d53bd ("stub: split out random seed part out of run()")
looks like refactoring but apparently it changed the logic when random
seed is refreshed in the ESP completely. Previously, process_random_seed()
was called when either:
- sd-stub was not present (LoaderFeatures var is unset) OR
- sd-stub was present but EFI_LOADER_FEATURE_RANDOM_SEED flag was unset.
Post-change, refresh_random_seed() bails under the exact same conditions (no
sd-stub or EFI_LOADER_FEATURE_RANDOM_SEED is unset) and thus
process_random_seed() is NOT called.
Restore the original logic. efivar_get_uint64_le()'s return value doesn't
require checking: loader_features is initialized to 0 and in case of failure it
stays untouched.
In case kernel-install is called to install what's already a UKI, 60-ukify
must be skipped. E.g. when distro shipped and signed UKI is being installed,
it is counter-productive to try to rebuild it with ukify. Also, the existing
script is not ready to handle UKIs with embedded initramfs.
Note, it is already possible to disable 60-ukify by setting
KERNEL_INSTALL_UKI_GENERATOR to something but in case it is not set, 60-ukify
assumes it should run.
systemd-cryptenroll complains (but succeeds!) upon binding to a signed PCR
policy:
$ systemd-cryptenroll --unlock-key-file=/tmp/passphrase --tpm2-device=auto
--tpm2-public-key=... --tpm2-signature=..." /tmp/tmp.img
ERROR:esys:src/tss2-esys/esys_iutil.c:394:iesys_handle_to_tpm_handle() Error: Esys invalid ESAPI handle (40000001).
WARNING:esys:src/tss2-esys/esys_iutil.c:415:iesys_is_platform_handle() Convert handle from TPM2_RH to ESYS_TR, got: 0x40000001
ERROR:esys:src/tss2-esys/esys_iutil.c:394:iesys_handle_to_tpm_handle() Error: Esys invalid ESAPI handle (40000001).
WARNING:esys:src/tss2-esys/esys_iutil.c:415:iesys_is_platform_handle() Convert handle from TPM2_RH to ESYS_TR, got: 0x4000000
New TPM2 token enrolled as key slot 1.
The problem seems to be that Esys_LoadExternal() function from tpm2-tss
expects a 'ESYS_TR_RH*' constant specifying the requested hierarchy and not
a 'TPM2_RH_*' one (see Esys_LoadExternal() -> Esys_LoadExternal_Async() ->
iesys_handle_to_tpm_handle() call chain).
It all works because Esys_LoadExternal_Async() falls back to using the
supplied values when iesys_handle_to_tpm_handle() fails:
r = iesys_handle_to_tpm_handle(hierarchy, &tpm_hierarchy);
if (r != TSS2_RC_SUCCESS) {
...
tpm_hierarchy = hierarchy;
}
Note, TPM2_RH_OWNER was used on purpose to support older tpm2-tss versions
(pre https://github.com/tpm2-software/tpm2-tss/pull/1531), use meson magic
to preserve compatibility.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
A copy paste error has crippled in the objcopy example in 'systemd-measure'
manual, "--change-section-vma" should reference the section being added,
not ".splash". When used as-is, the resulting UKI is unbootable.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Vitaly Kuznetsov