Let's make sure IMAGE_ID/IMAGE_VERSION are properly honoured, and
explain in a long comment why.
Let's also use ID= field again, which was lost by accident.
(While we are at it do some minimal OOM checks wherever we touch
something)
Unfortunately they forgot the "const" decoration on the MetaiMatch()
prototype, but let that omission not leak into our code, let's hide it
away in the innermost use.
Moving all of the gnu-efi detection into src/boot/efi/meson.build makes
more sense than having it partially split.
And thanks to subdir_done() we can simplify the code a lot.
Fixes: #21258
This allows starting systemd-boot from \EFI\Linux for easier testing
and bisection without risking an unbootable system as the user does not
need to replace their working loader.
efi_arch is set to whatever meson returns from host_machine.cpu_family() and
gnu_efi_arch is then set accordingly.
On x86, efi_arch == x86 and gnu_efi_arch == ia32. Surprisingly, compilation
worked (without disabling some instruction sets) and nobody ever complained
about systemd-bootia32.efi not working.
This brings the final list of compiler arguments more in line with
how meson does things. In particular, --buildtype=plain will not
add any optimizations on its own (and would have to be provided
through CFLAGS=).
These flags are used by gnu-efi. Adding --no-undefined even allows
us to drop the no-undefined-symbols.sh test in favor of immediate
compile time errors.
This is not a hosted environment and we should not pretend otherwise
if -ffreestanding is not supported.
With EFI strings being in UCS2, it is not supported to build without
-fshort-wchar as gcc/clang default to a w_char_t size of 4 bytes.
This also makes the charset for wide chars explicit on gcc. This way
we get a nice error message if anyone ever tries to add 💩 to strings.
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.
This is useful if the auto-firmware setting has been disabled. The
keys used here are based on what the majority of firmware employ in
the wild.
This also ensures there's a chance for the user to discover this in
case they were too slow during POST or simply used the wrong ones.
This version is from 2017 and should be stale enough to not cause
an outrage. All the relevant distros have it or a newer version.
We also already depend on some symbols defined in 3.0.5 anyway,
so let's take the opportunity to reduce our missing_efi.h
baggage.
The uefi_call_wrapper exists to convert to the right calling convention
and presumably predates compilers that can do so natively. The only
architecture where this is even needed is x86_64.
But because we are building with GNU_EFI_USE_MS_ABI defined, the
EFIAPI macro tells the compiler to use the right calling convention
for EFI functions. Our shim callback (which is called by EFI itself)
already relies on this.
This also adds a safety check to make se we are compiling with
GNU_EFI_USE_MS_ABI defined and also adds it to the compiler args
unconditionally. It is only used with x86_64 anyways, so it should
be fine to do so. EFI_FUNCTION_WRAPPER is unused in gnu-efi, so
it is dropped.
We are already using void in several places and having a screaming
typedef for void feels pointless. There are also CONST, IN, OUT
and OPTIONAL which we aren't using either.
This leaves missing_efi.h to keep it in line with how they are
defined in gnu-efi and/or the specs.
A little helper function and some unusual formatting makes this
whole thing a lot easier on the eyes. Also, right-aligning the
properties for better readability at runtime.
Let's define two helpers strdupa_safe() + strndupa_safe() which do the
same as their non-safe counterparts, except that they abort if called
with allocations larger than ALLOCA_MAX.
This should ensure that all our alloca() based allocations are subject
to this limit.
afaics glibc offers three alloca() based APIs: alloca() itself,
strndupa() + strdupa(). With this we have now replacements for all of
them, that take the limit into account.
Lennart Poettering
Jan Janssen
Luca Boccassi
Zbigniew Jędrzejewski-Szmek
Dimitri Papadopoulos
Max Resch