Currently in mkosi and ukify we use sbsigntools to do secure boot
signing. This has multiple issues:
- sbsigntools is practically unmaintained, sbvarsign is completely
broken with the latest gnu-efi when built without -fshort-wchar and
upstream has completely ignored my bug report about this.
- sbsigntools only supports openssl engines and not the new providers
API.
- sbsigntools doesn't allow us to cache hardware token pins in the
kernel keyring like we do nowadays when we sign stuff ourselves in
systemd-repart or systemd-measure
There are alternative tools like sbctl and pesign but these do not
support caching hardware token pins in the kernel keyring either.
To get around the issues with sbsigntools, let's introduce our own
tool systemd-sbsign to do secure boot signing. This allows us to
take advantage of our own openssl infra so that hardware token pins
are cached in the kernel keyring as expected and we get openssl
provider support as well.
We used both, in fact "Devicetree" was more common. But we have a general rule
that we capitalize all words in names and also we have a DeviceTree=
configuration setting, which we cannot change. If we use two different
spelllings, this will make it harder for people to use the correct one in
config files. So use the "DeviceTree" spelling everywhere.
Since v256 we completely fail to boot if v1 is configured. Fedora 41 was just
released with v256.7 and this is probably the first major exposure of users to
this code. It turns out not work very well. Fedora switched to v2 as default in
F31 (2019) and at that time some people added configuration to use v1 either
because of Docker or for other reasons. But it's been long enough ago that
people don't remember this and are now very unhappy when the system refuses to
boot after an upgrade.
Refusing to boot is also unnecessarilly punishing to users. For machines that
are used remotely, this could mean somebody needs to physically access the
machine. For other users, the machine might be the only way to access the net
and help, and people might not know how to set kernel parameters without some
docs. And because this is in systemd, after an upgrade all boot choices are
affected, and it's not possible to e.g. select an older kernel for boot. And
crashing the machine doesn't really serve our goal either: we were giving a
hint how to continue using v1 and nothing else.
If the new override is configured, warn and immediately boot to v1.
If v1 is configured w/o the override, warn and wait 30 s and boot to v2.
Also give a hint how to switch to v2.
https://bugzilla.redhat.com/show_bug.cgi?id=2323323https://bugzilla.redhat.com/show_bug.cgi?id=2323345https://bugzilla.redhat.com/show_bug.cgi?id=2322467https://www.reddit.com/r/Fedora/comments/1gfcyw9/refusing_to_run_under_cgroup_01_sy_specified_on/
The advice is to set systemd.unified_cgroup_hierarchy=1 (instead of removing
systemd.unified_cgroup_hierarchy=0). I think this is easier to convey. Users
who are understand what is going on can just remove the option instead.
The caching is dropped in cg_is_legacy_wanted(). It turns out that the
order in which those functions are called during early setup is very fragile.
If cg_is_legacy_wanted() is called before we have set up the v2 hierarchy,
we incorrectly cache a true answer. The function is called just a handful
of times at most, so we don't really need to cache the response.
Currently in mkosi and ukify we use sbsigntools to do secure boot
signing. This has multiple issues:
- sbsigntools is practically unmaintained, sbvarsign is completely
broken with the latest gnu-efi when built without -fshort-wchar and
upstream has completely ignored my bug report about this.
- sbsigntools only supports openssl engines and not the new providers
API.
- sbsigntools doesn't allow us to cache hardware token pins in the
kernel keyring like we do nowadays when we sign stuff ourselves in
systemd-repart or systemd-measure
There are alternative tools like sbctl and pesign but these do not
support caching hardware token pins in the kernel keyring either.
To get around the issues with sbsigntools, let's introduce our own
tool systemd-sbsign to do secure boot signing. This allows us to
take advantage of our own openssl infra so that hardware token pins
are cached in the kernel keyring as expected and we get openssl
provider support as well.
.dtbauto section contains DT blobs, just like .dtb, the difference is
that multiple .dtbauto sections are allowed to be in a UKI and only one
is selected automatically
Temporarily drop an assert_cc() check in systemd-measure to make it compilable before the next commit
It is normal for DHCP leases not to have DNR options. We need to be less
verbose and more forgiving in these cases. Also, if either DHCP does not
have DNR options, make sure to still consider any DHCPv6/RA options.
Fixes: c7c9e3c7c0 (network: adjust log message about DNR)
While for engines we have ENGINE_ctrl() to set the UI method for the
second PIN prompt, for openssl providers we don't have such a feature
which means we get the default openssl UI for the second pin prompt.
Instead, let's set the default UI method which does get used for the
second pin prompt by the pkcs11 provider.
And use it when explicit reconfiguration is requested by Reconfigure() DBus method
or networkd certainly detects that connected network is changed.
Otherwise do not use the flag especially when we come back from sleep mode.
E.g. when a .network file is updated, but DHCP setting is unchanged, it
is not necessary to drop acquired DHCP lease.
So, let's not stop DHCP client and friends in link_reconfigure_impl(),
but stop them later when we know they are not necessary anymore.
Still DHCP clients and friends are stopped and leases are dropped when
the explicit reconfiguration is requested
When a reconfiguration of an interface is triggered, previously we
call link_foreignize_config(), which sets all static configurations as
foreign, then later call link_drop_foreign_config(), which drops
unnecessary foreign configurations.
This commit merges these two steps into one, link_drop_unmanaged_config(),
which drops unnecessary static and foreign configurations.
Also, this renames link_drop_managed_configs() to
link_drop_static_config(), as it only drops static configurations.
Note that dynamically aquired configurations are dropped by
link_stop_engines().
Effectively no functional changes, just refactoring and preparation for
later changes.
- convert boolean flag 'force' to LinkReconfigurationFlag enum,
- merge link_reconfigure() and reconfigure_handler_on_bus_method_reload() as
link_reconfigure_full(),
- Rename ReconfigureData -> LinkReconfigurationData,
- make Reconfigure() DBus message wait for reconfiguration being
started before sending reply.
This new setting allows unsharing the pid namespace in a unit. Because
you have to fork to get a process into a pid namespace, we fork in
systemd-executor to get into the new pid namespace. The parent then
sends the pid of the child process back to the manager and exits while
the child process continues on with the rest of exec_invoke() and then
executes the actual payload.
Communicating the child pid is done via a new pidref socket pair that is
set up on manager startup.
We unshare the PID namespace right before the mount namespace so we
mount procfs correctly. Note PrivatePIDs=yes always implies MountAPIVFS=yes
to mount procfs.
When running unprivileged in a user session, user namespace is set up first
to allow for PID namespace to be unshared. However, when running in
privileged mode, we unshare the user namespace last to ensure the user
namespace does not own the PID namespace and cannot break out of the sandbox.
Note we disallow Type=forking services from using PrivatePIDs=yes since the
init proess inside the PID namespace must not exit for other processes in
the namespace to exist.
Note Daan De Meyer did the original work for this commit with Ryan Wilson
addressing follow-ups.
Co-authored-by: Daan De Meyer <daan.j.demeyer@gmail.com>