Now that kernel-install creates the machine-id directory, we don't need to do
this is 'bootctl install', and in fact it's better not to do this since it
might never be necessary. So let's change the default behaviour to 'no'.
I kept support for 'auto' to maintain backwards compatibility, even though the
default was changed. Previous behaviour can be requested by specifying
--make-machine-id-directory=auto.
This is a natural extension of d6bce6e224: if we are installing sd-boot, we
want to use the sd-boot layout, so let's write the appropriate
KERNEL_INSTALL_LAYOUT setting. Effectively, if we do 'booctl install',
kernel-install will not autodetect the layout anymore.
And 357376d0bb added support for KERNEL_INSTALL_MACHINE_ID. We need to support
it here too. We both read it, so that we create the right directories, and also
write it if it wasn't written yet and we created some directories using it, so
that kernel-install that is executed later knows the machine-id that matches
the directories we crated.
The code is changed in some places to fail if we can't figure out the current
status. When installing the boot loader it's probably better not to guess.
if /usr/lib/systemd/boot/efi/systemd-bootx64.efi.signed exists
install that instead of /usr/lib/systemd/boot/efi/systemd-bootx64.efi
the idea is that SecureBoot tooling can create the efi.signed file
whenever /usr/lib/systemd/boot/efi/systemd-bootx64.efi from the package
is updated.
Let's make sure '@' is never written as entry ID into any EFI variable,
as we want the ability to add new ids like this later on, with them
resulting in a clear error on older implementations.
These functions are used pretty much independently of locale, i.e. the
only info relevant is whether th locale is UTF-8 or not. Hence let's
give this its own pair of .c/.h files.
"bootctl update" tries to add sd-boot to the EFI boot loader list if it
is not already there. To do so, it uses find_slot() which finds the
proper BootXXXX slot ID to use and also returns 1 if an existing sd-boot
entry was found at this ID or 0 if it is a new unused ID. In "update"
case install_variables() only writes the entry in case 0 (no existing
entry).
However, find_slot() erroneously returns 1 if it finds a gap in the Boot
IDs (i.e. when not resorting to max(ids) + 1). This causes
"bootctl update" to not add a missing systemd-boot boot entry if the
existing BootXXXX entry IDs are not consecutive.
Fix that by returning 0 in find_slot() when an empty gap ID is selected
to make it match the behavior when selecting an empty non-gap ID.
Let's be paranoid and do something useful if we operate with empty
haystack/needle. This doesn't actually fix anything, as the places as
far as I can see check for non-emptyness already beforehand, but I will
sleep safer at night, if we don't even allow the trap to be fallen in,
ever, even if the code is changed sooner or later.
This is like memmem_safe() but returns a pointer after the needle,
instead to the beginning of the needle.
This is then used at one place. Not much, but it makes me sleep safer at
night, as it avoids the manual counting done so far.
In general we almost never hit those asserts in production code, so users see
them very rarely, if ever. But either way, we just need something that users
can pass to the developers.
We have quite a few of those asserts, and some have fairly nice messages, but
many are like "WTF?" or "???" or "unexpected something". The error that is
printed includes the file location, and function name. In almost all functions
there's at most one assert, so the function name alone is enough to identify
the failure for a developer. So we don't get much extra from the message, and
we might just as well drop them.
Dropping them makes our code a tiny bit smaller, and most importantly, improves
development experience by making it easy to insert such an assert in the code
without thinking how to phrase the argument.
Previously, the "bootctl update" logic would refrain from downrgading a
boot loader, but if the boot loader that is installed already matched
the version we could install we'd install it anyway, under the
assumption this was effectively without effect. This behaviour was handy
while developing boot loaders, since installing a modified boot loader
didn't require a version bump.
However, outside of the systems of boot loader developers I don't think
this behaviour makes much sense: we should always emphasize doing
minimal changes to the ESP, hence when an update is supposedly not
necessary, then don't do it. Only update if it really makes sense, to
minimize writes to the ESP. Updating the boot loader is a good thing
after all, but doing so redundantly is not.
Also, downgrade the message about this to LOG_NOTICE, given this
shouldn't be a reason to log.
Finally, exit cleanly in this cases (or if another boot loader is
detected)
The logic is that if the options are updated after boot, we *don't* use
the new value. But we still want to print out the changed contents in
bootctl as to not confuse people.
Fixes#19597.
Also https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=988450.
$ build/bootctl systemd-efi-options
quiet
Note: SystemdOptions EFI variable has been modified since boot. New value: debug
The hint is printed to stderr, so scripts should not be confused.
Creating those string dynamically at runtime is slow and unnecessary.
Let's use static strings with a bit of macro magic and the let the compiler
coalesce as much as possible.
$ size build/src/shared/libsystemd-shared-248.so{.old,}
text data bss dec hex filename
2813453 94572 4584 2912609 2c7161 build/src/shared/libsystemd-shared-248.so.old
2812309 94564 4584 2911457 2c6ce1 build/src/shared/libsystemd-shared-248.so
A nice side-effect is that the same form is used everywhere, so it's easier to
figure out all variables that are used, and where each specific variable is
used.
C.f. 2b0445262a.
Note: 'const char *foo = alloca(…);' seems OK. Our coding style document and
alloca(3) only warn against using alloca() in function invocations. Declaring
both stack variable and alloca at the same time should be fine: no matter in
which order they happen, i.e. if the pointer variable is above the contents,
or the contents are above the pointer, or even if the pointer is elided by the
compiler, everything should be fine.
Some motherboards convert the path to uppercase under certain circumstances
(e.g. after booting into the Boot Menu in the ASUS ROG STRIX B350-F GAMING).
With some versions of the compiler, the _cleanup_ attr makes it think
the variable might be freed/closed when uninitialized, even though it
cannot happen. The added cost is small enough to be worth the benefit,
and optimized builds will help reduce it even further.
I think this formatting was originally used because it simplified
adding new options to the help messages. However, these days, most
tools their help message end with "\nSee the %s for details.\n" so
the final line almost never has to be edited which eliminates the
benefit of the custom formatting used for printf() help messages.
Let's make things more consistent and use the same formatting for
printf() help messages that we use everywhere else.
Prompted by https://github.com/systemd/systemd/pull/18355#discussion_r567241580
Using `bootctl set-default @current` will set the default loader entry
to the currently booted entry as read from the `LoaderEntrySelected` EFI
variable.
Also `bootctl set-oneshot @current` will set the oneshot loader entry to
the current booted entry.
Correspondingly `@default` and `@oneshot` can be used to read from the
LoaderEntryDefault and LoaderEntryOneshot EFI variables.
bootctl implements three types of operation: those that work with an EFI
boot loader, those which work with any EFI boot loader that implements
the boot loader spec + interface, and finally those specific to sd-boot.
Previously the --help text and the man page mixed them all up. Let's put
them clearly in three separate sections however, to communicate clearly
what is supposed to work everywhere, and what is specific to
systemd-boot or boot loaders implementing the two specs.
This adjusts wording here and there, but is mostly just about
re-ordering existing docs, and putting them under new sections.
The machine-id is used to create a few directories and setup a default
loader entry in loader.conf. Having bootctl create the directories
itself is not particularly useful as it does not put anything in them
and bootctl install is not guaranteed to be called before an initramfs
tool like kernel-install so other programs will always need to have
logic to create the directories themselves if they happen to be called
before bootctl install is called.
On top of this, when using unified kernel images, these are installed to
$BOOT/EFI/Linux which removes the need to have the directories created
by bootctl at all. This further indicates that these directories should
be created by the program that puts something in them rather than by
bootctl.
Removing the machine-id dependency allows bootctl install to be called
even when there's no machine-id in the image. This is useful for image
builders such as mkosi which don't have a machine-id when
installing systemd-boot (via bootctl) because it should only be
generated by systemd when the final image is booted.
The default entry in loader.conf based on the machine-id in loader.conf
is also removed which shouldn't be a massive loss in usability overall.
This commit reverts commit 341890d.