The UEFI spec has a generic `Path` node representation that can be used
for device path nodes that are unknown. So we can use that instead of
giving up when we see a node other than FilePath.
This also simplifies the FilePath case by just using xasprintf(). The
code is really just a fallback for silly firmware that does not
implement EFI_DEVICE_PATH_TO_TEXT_PROTOCOL (looking at you, Apple).
The correctness of this was tested by round-tripping it through
EFI_DEVICE_PATH_FROM_TEXT_PROTOCOL, which yielded an identical device
compared to our input path.
This takes heavy inspiration from @zx2c4 (Jason A. Donenfeld)'s
PR #25531 but changes it considerably, but always going by fd instead of
paths, and only warning about the side file itself and the ESP mount
point, nothing else. This shuld be more than enough and should not be
brittle against concurrent path modifications.
Replaces: #25531
This changes a boolean param into a proper bitflag field.
Given this only defines a single flag for now this doesn't look like
much of an improvement. But we'll add another flag shortly, where it
starts to make more sense.
We are using HandleProtocol everywhere except in these few cases. This
unifies on HandleProtocol as it is simpler to use and equivalent to
OpenProtocol.
The only difference between the two is that OpenProtocol attributes the
opened protocol to a firmware-owned handle instead of our image handle.
This has no real use for regular UEFI applications as any protocols
opened via BY_HANDLE or GET_PROTOCOL is not required to be closed. In
fact, when a protocol is uninstalled it will do nothing more than reduce
the open count for these.
Remove _cleanup_tpm2_context_ and _cleanup_tpm2_handle_ macros, replacing their
use with _cleanup_(tpm2_context_unrefp) and _cleanup_(tpm2_handle_freep),
respectively.
Without this, the tests would generally be skipped, since we haven't made a
release with the addon stub yet. But even if the file is there, we always want
to test the freshly-built item.
Previously, unprivileged mode for find_esp_and_warn() and
find_xbootldr_and_warn() could be enabled or disabled. With this change
it can also be set to negative in which case the functions will enable
it automatically if found to be executing without privileges.
This just moves te geteuid() check we often do for the param inside of
the functions.
At the same time internally in the functions we also pass around the
VerifyESPFlags field across the various functions instead of booleans.
Both changes are just refactoring. No changes in behaviour.
In 9b9f6aa412 (#27069)
we changed get_file_version to return 0 instead of 1 on success.
However we did not update the printing of the version number to
handle this change so we would never print the version number.
Files placed in /EFI/Linux/UKI.efi.extra.d/ and /loader/addons/ are
opened and verified using the LoadImage protocol, and will thus get
verified via shim/firmware.
If they are valid signed PE files, the .cmdline section will be
extracted and appended. If there are multiple addons in each directory,
they will be parsed in alphanumerical order.
Optionally the .uname sections are also matched if present, so
that they can be used to filter out addons as well if needed, and only
addons that correspond exactly to the UKI being loaded are used.
It is recommended to also always add a .sbat section to addons, so
that they can be mass-revoked with just a policy update.
The files must have a .addon.efi suffix.
Files in the per-UKI directory are parsed, sorted, measured and
appended first. Then, files in the generic directory are processed.
We'll use it from the stub to validate files. Requires Shim 5.18.
By default, Shim uninstalls its protocol when calling StartImage(),
so when loading systemd-boot via shim and then loading an UKI, the
UKI's sd-stub will no longer be able to use the shim verification
protocol by default.
PCR1, where SMBIOS strings are measured, is filled with data that is not
under the control of the machine owner. Measure cmdline extensions in
PCR12 too, where we measure other optional addons that are loaded by
sd-stub.
The kernel, systemd, and many other things print their version during boot.
sd-boot and sd-stub are also important, so let's print the version if EFI_DEBUG.
(If !EFI_DEBUG, continue to be quiet.)
When updating the docs, I saw that that the text in HACKING.md was out of date.
Instead of trying to update the instructions there, make it shorter and refer
the reader to tools/debug-sd-boot.sh for details.
Let's use the same common directory as the unit logic uses.
This means we have less to clean up, and opens the door to eventually
allow unprivileged operation of the
mount_image_privately_interactively() logic.
We were using the wrong memory type when allocating pool memory. This
does not seem to cause a problem on x86, but the kernel will fail to
boot at least on ARM in QEMU.
This is caused by mixing different allocation types which ended up
breaking the kernel or EDK2 during boot services exit. Commit
2f3c3b0bee appears to fix this boot
failure because it was replacing the gnu-efi xpool_print with xasprintf
thereby unifying the allocation type.
But this same issue can also happen without this fix somehow when the
random-seed logic is in use.
Fixes: #27371
__builtin_popcount() is a bit of a mouthful, so let's provide a helper.
Using _Generic has the advantage that if a type other then the ones on
the list is given, compilation will fail. This is nice, because if by any
change we pass a wider type, it is rejected immediately instead of being
truncated.
log.h is also needed. It is included transitively, but let's include it
directly.
macro.h is *not* needed.
On x86 EFI follows the windows ABI, which expects 8-byte aligned long
long. The x86 sysv ELF ABI expects them to be 8-byte aligned when used
alone, but 4-byte aligned when they appear inside of structs:
struct S {
int i;
long long ll;
};
// _Static_assert(sizeof(struct S) == 12, "x86 sysv ABI");
_Static_assert(sizeof(struct S) == 16, "EFI/MS ABI");
To get the behavior we need when building with sysv ELF ABI we need to
pass '-malign-double' to the compiler as done by EDK2.
This in turn will make ubsan unhappy as the stack may not be properly
aligned on entry, so we have to tell the compiler explicitly to re-align
the stack on entry to efi_main.
This fixes loading EFI drivers on x86 that were previously always
rejected as the EFI_LOADED_IMAGE_PROTOCOL had a wrong memory layout.
See also: https://github.com/rhboot/shim/pull/516