This introduces PinnedResources as a structure combining pinned
references to a root directory, root image, or root mstack. This is not
only easier to work with, but essential to make certain unpriv things
work, as we need some mechanism to pin resources before we drop into a
userns which might possibly not provide access anymore to those
resources.
Hence this does two things: introduce the new structure, and immediately
hook it up so that we pin things properly before dropping into userns,
and then makes use of this after dropping the right way, and enables
unpriv userns operation.
The concept is generic enough to eventually implement extension images +
mount images with the same structure, but in order to keep the changes
managable this is left for another time.
(This also makes one further clean-up: client-side verity-reuse checks
are moved server side if we are unpriv. Previously we'd do them client
side, but they were doomed to fail because of lack of privs. Hence let's
drop the client side if we are unpriv and purely do them server-side in
that case.)
So far we opened a new Varlink connection for every mountfsd/nsresourced
method call. Given each tool only does a very small number of calls
(usually 1…5) on them and the connections are cheap this is not too
wasteful. Nonetheless, let's do something about it, and allow reusing
the connection for multiple calls.
This not only makes things a bit more efficient, but has one more
important benefit: Varlink connections pin the security context of the
client when connecting. This means that varlink method calls done with a
connection established while some code was privileged will still operate
as privieged once privs are dropped, until the connection is closed.
This pinning effect is really nice, as it gives us behaviour in a
"capability system" like scheme. Later code is going to use that to
continue doing certain priv userns ops even after unsharing userns and
becoming fully unpriv.
A later commit will add transient allocation of user namespaces with
dynamic UID range assignment. That creates certain permission issues.
Let's hence allow them to be handled gracefully in case the 'ignore'
field is set for a mount.
This is not just refactoring, but has the big benefit that it makes us
indepdendent from a temporary directory we might not have enough access
to create. (This matters with the new PrivateUsers=managed).
We have two very similar checks in place: in some contexts we want to
know if *any* RootDirectory= is configured, in the other we want to
suppress if it is configured to our regular root. Let's add a helper for
both (even if we only need it once), to make the mirrored behaviour
clear.
Let's flush out all response state from the job, but let's keep the
request data previously configured, in particular the headers set. This
is useful to re-request a resource, just with a slightly modified or
identical URL.
Observed with the tpm2 provider and the tpm2tss engine was that the
auth process failed because the provider/engine could not ask for the
PIN through the callback, resulting in:
"Failed to load private key from ...: Input/output error"
Apparently the default UI method is not enough and the key setup
functions expect an explicit method.
Pass the existing UI method through as callback for the key setup.
The warning will still be reported if XAUTHORITY is set but not exported.
However, such scenario is unlikely for xinitrc.d scripts environment.
Fixes#40745
Signed-off-by: Dmytro Bagrii <dimich.dmb@gmail.com>
Follow-up to 02cab70acf. pe_hash(),
section_offset_cmp() and uki_hash() still had a bunch of raw accesses
to LE fields (e_lfanew, SizeOfHeaders, PointerToRawData, SizeOfRawData,
VirtualSize, certificate_table->Size) without le32toh(), so they'd
produce garbage on big-endian.
Also wrap VirtualSize in bootspec.c for consistency.
This was made a strv to handle either directories or raw images but
since we now handle that via multiple PickFilter instances, we don't
need suffixes to be a strv anymore.
Fixes failure on Rawhide:
TEST-88-UPGRADE.sh[512]: Transaction failed: Rpm transaction failed.
TEST-88-UPGRADE.sh[512]: Warning: skipped OpenPGP checks for 15 packages from repository: @commandline
TEST-88-UPGRADE.sh[512]: - package systemd-shared-260~devel-20260218150812.fc45.x86_64 does not verify: no signature
You can register whatever process you want in the user machined instance
that is running in the same namespace as pid 1 as machined won't be allowed
to do anything privileged anyway that could be dangerous when running as a user
instance.
We have to skip the check as we user machined instances don't have
privileges to inspect pid1's user namespaces.
Lennart Poettering
Kai Lüke
Dmytro Bagrii
Oblivionsage
Daan De Meyer
David Santamaría Rogado
Luca Boccassi
Mario Limonciello (AMD)
Zbigniew Jędrzejewski-Szmek
dependabot[bot]