Offline encryption can be done without mounting the luks device. For
now we still use loop devices to split out the partition we want to
write to but in a later commit we'll replace this with a regular file.
For offline encryption, we need to keep 2x the luks header size space
free at the end of the partition, so this means our encrypted partitions
will be 16M larger than before.
mkfs.vfat doesn't support specifying a root directory to bootstrap
the filesystem from (see https://github.com/dosfstools/dosfstools/issues/183).
Instead, we can use the mcopy tool from the mtools package to copy
files into the vfat filesystem after creating it without needing to
mount the vfat filesystem.
Let's allow filtering the partitions to operate on by partition
type UUID. This is necessary when building bootable images with a
verity protected root/usr partition as we can only build the UKI
image when we have the verity roothash which means we cannot populate
the EFI partition yet when we run repart initially to determine the
verity roothash.
If we skip some partition types in a first run of systemd-repart,
we don't want their partition numbers to be different than usual,
so let's change the allocation of partition numbers to account for
that.
Instead of exposing just the partition type UUID, let's expose the
GptPartitionType struct, which has a lot more information available
in a much more accessible way.
Also, let's get rid of SECONDARY/OTHER in PartitionDesignator. These
were only there to support preferred architectures in dissect-image.c,
but we can easily handle that by comparing architectures when we decide
whether to override a partition. This is done in a new function
compare_arch().
On some kernels/distros (RHEL/aarch64) /dev/mem is
turned off. This means that the ACPI FPDT data is
missing from systemd-analyze output when /dev/mem
fails to provide the boot times.
Instead recent kernels can export that data from
/sys/firmware/acpi/fpdt/boot/ entries. Use that
information if available first.
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Since this runs at shutdown to write a new seed, we should also keep the
bootloader's seed maximally fresh by doing the same. So we follow the
same pattern - hash some new random bytes with the old seed to make a
new seed. We let this fail without warning, because it's just an
opportunistic thing. If the user happens to have set up the random seed
with bootctl, and the RNG is initialized, then things should be fine. If
not, we create a new seed if systemd-boot is in use. And if not, then we
just don't do anything.
Rather than passing seeds up to userspace via EFI variables, pass seeds
directly to the kernel's EFI stub loader, via LINUX_EFI_RANDOM_SEED_TABLE_GUID.
EFI variables can potentially leak and suffer from forward secrecy
issues, and processing these with userspace means that they are
initialized much too late in boot to be useful. In contrast,
LINUX_EFI_RANDOM_SEED_TABLE_GUID uses EFI configuration tables, and so
is hidden from userspace entirely, and is parsed extremely early on by
the kernel, so that every single call to get_random_bytes() by the
kernel is seeded.
In order to do this properly, we use a bit more robust hashing scheme,
and make sure that each input is properly memzeroed out after use. The
scheme is:
key = HASH(LABEL || sizeof(input1) || input1 || ... || sizeof(inputN) || inputN)
new_disk_seed = HASH(key || 0)
seed_for_linux = HASH(key || 1)
The various inputs are:
- LINUX_EFI_RANDOM_SEED_TABLE_GUID from prior bootloaders
- 256 bits of seed from EFI's RNG
- The (immutable) system token, from its EFI variable
- The prior on-disk seed
- The UEFI monotonic counter
- A timestamp
This also adjusts the secure boot semantics, so that the operation is
only aborted if it's not possible to get random bytes from EFI's RNG or
a prior boot stage. With the proper hashing scheme, this should make
boot seeds safe even on secure boot.
There is currently a bug in Linux's EFI stub in which if the EFI stub
manages to generate random bytes on its own using EFI's RNG, it will
ignore what the bootloader passes. That's annoying, but it means that
either way, via systemd-boot or via EFI stub's mechanism, the RNG *does*
get initialized in a good safe way. And this bug is now fixed in the
efi.git tree, and will hopefully be backported to older kernels.
As the kernel recommends, the resultant seeds are 256 bits and are
allocated using pool memory of type EfiACPIReclaimMemory, so that it
gets freed at the right moment in boot.
In provision.conf we ship:
d- /root :0700 root :root -
d- /root/.ssh :0700 root :root -
These are allowed to fail, for example on a read-only filesystem. But they still
log at error level, which is annoying and gets flagged. Tune those specific errors
down to info.
There are likely more that could be tuned down, but the important thing is to cover
the tmpfiles.d that we ship right now.
Before:
$ echo -e "d- /root :0700 root :root - \nd- /root/.ssh :0700 root :root -" | SYSTEMD_LOG_LEVEL=err build/systemd-tmpfiles --root=/tmp/img --create -
Failed to create directory or subvolume "/tmp/img/root": Read-only file system
Failed to open path '/tmp/img/root': No such file or directory
$
After:
$ echo -e "d- /root :0700 root :root - \nd- /root/.ssh :0700 root :root -" | SYSTEMD_LOG_LEVEL=err build/systemd-tmpfiles --root=/tmp/img --create -
$
When a module is blacklisted using module_blacklist=
we shouldn't fail with 'Operation not permitted'.
Instead we check for it and skip it if this is the case.
Let's make use of the new flag whenever we access the ESP or XBOOTLDR.
The resources we make use of in these partitions can't possibly use
symlinks (because UEFI knows no symlink concept), and they are untrusted
territory, hence under no circumstances we should be tricked into
following symlinks that shouldn't be there in the first place.
Of course, you might argue thta ESP/XBOOTLDR are VFAT and thus don#t
know symlinks. But the thing is, they don#t have to be. Firmware can
support other file systems too, and people can use efifs to gain access
to arbitrary Linux file systems from EFI. Hence, let's better be safe
than sorry.
This is useful when operating in the ESP, which is untrusted territory,
and where under no circumstances we should be tricked by symlinks into
doing anything we don't want to.
Let's change the return semantics of strv_make_nulstr() so that we can
properly distuingish the case where we have a no entries in the nulstr
from the case where we have a single empty string in a nulstr.
Previously we couldn't distuingish those, we'd in both cases return a
size of zero, and a buffer with two NUL bytes.
With this change, we'll still return a buffer with two NULL bytes, but
for the case where no entries are defined we'll return a size of zero,
and where we have two a size of one.
This is a good idea, as it makes sure we can properly handle all corner
cases.
Nowadays the function is used by one place only: ask-password-api.c. The
corner case never mattered there, since it was used to serialize
passwords, and it was known that there was exactly one password, not
less. But let's clean this up. This means the subtraction of the final
NUL byte now happens in ask-password-api.c instead.
if the nulstr is not nul-terminated, we shouldn't use strndup() but
memdup_suffix0(), to not trip up static analyzers which imply we are
duping a string here.
This rework the logic for handling the "header" cells a bit. Instead of
special casing the first row in regards to uppercasing/coloring let's
just intrduce a proper cell type TABLE_HEADER which is in most ways
identical to TABLE_STRING except that it defaults to uppercase output
and underlined coloring.
This is mostly refactoring, but I think it makes a ton of sense as it
makes the first row less special and you could in fact insert
TABLE_HEADER (and in fact TABLE_FIELD) cells wherever you like and
something sensible would happen (i.e. a string cell is displayed with
a specific formatting).
If a battery is not present or its status is not discharging, then
the battery should not be used as a power source.
Let's count batteries currently discharging.
Fixes#25316.
Daan De Meyer
Li kunyu
Jeremy Linton
Jason A. Donenfeld
Yu Watanabe
Luca Boccassi
Mike Yuan
Jan Janssen
David Tardon
Lennart Poettering