Although U-Boot supports capsule update on-disk, it's lack of support for
SetVariable at runtime prevents applications like fwupd from using it.
In order to perform the capsule update on-disk the spec says that the OS
must copy the capsule to the \EFI\UpdateCapsule directory and set a bit in
the OsIndications variable. The firmware then checks for the
EFI_OS_INDICATIONS_FILE_CAPSULE_DELIVERY_SUPPORTED bit in OsIndications
variable, which is set by the submitter to trigger processing of the
capsule on the next reboot.
Let's add a config option which ignores the bit and just relies on the
capsule being present. Since U-Boot deletes the capsule while processing
it, we won't end up applying it multiple times.
Note that this is allowed for all capsules. In the future, once
authenticated capsules are fully supported, we can limit the functionality
to those only.
Signed-off-by: apalos <ilias.apalodimas@linaro.org>
Reword Kconfig description.
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
After each reboot we must clear flag
EFI_OS_INDICATIONS_FILE_CAPSULE_DELIVERY_SUPPORTED in variable
OsIndications.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Improve efi_query_variable_info() to check the parameter settings and
return correct error code according to the UEFI Specification 2.9,
and the Self Certification Test (SCT) II Case Specification, June
2017, chapter 4.1.4 QueryVariableInfo().
Reported-by: Kazuhiko Sakamoto <sakamoto.kazuhiko@socionext.com>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
After if we should use parentheses to keep the code readable.
Fixes: a95f4c8859 ("efi_loader: NULL dereference in EFI console")
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
We only install FMPs if a CapsuleUpdate is requested. Since we now have an
ESRT table which relies on FMPs to build the required information, it
makes more sense to unconditionally install them. This will allow userspace
applications (e.g fwupd) to make use of the ERST and provide us with files
we can use to run CapsuleUpdate on-disk
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Chapter 23 of the EFI spec (rev 2.9) says:
"A specific updatable hardware firmware store must be represented by
exactly one FMP instance".
This is not the case for us, since both of our FMP protocols can be
installed at the same time because they are controlled by a single
'dfu_alt_info' env variable.
So make the config options depend on each other and allow the user to
install one of them at any given time. If we fix the meta-data provided
by the 'dfu_alt_info' in the future, to hint about the capsule type
(fit or raw) we can revise this and enable both FMPs to be installed, as
long as they target different firmware hardware stores
Note that we are not using a Kconfig 'choice' on purpose, since we
want to allow both of those to be installed and tested in sandbox
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
When running the efidebug capsule disk-update command, the efi_fmp_raw
protocol installation fails with 2 (EFI_INVALID_PARAMETER) as below.
This is because the code passes efi_root instead of the handle local var.
=> efidebug capsule disk-update
EFI: Call: efi_install_multiple_protocol_interfaces( &handle, &efi_guid_firmware_management_protocol, &efi_fmp_fit, NULL)
EFI: Entry efi_install_multiple_protocol_interfaces(00000000fbaf5988)
EFI: Call: efi_install_protocol_interface( handle, protocol, EFI_NATIVE_INTERFACE, protocol_interface)
EFI: Entry efi_install_protocol_interface(00000000fbaf5988, 86c77a67-0b97-4633-a187-49104d0685c7, 0, 00000000fbfa6ee8)
EFI: new handle 00000000fbb37520
EFI: Exit: efi_install_protocol_interface: 0
EFI: 0 returned by efi_install_protocol_interface( handle, protocol, EFI_NATIVE_INTERFACE, protocol_interface)
EFI: Exit: efi_install_multiple_protocol_interfaces: 0
EFI: 0 returned by efi_install_multiple_protocol_interfaces( &handle, &efi_guid_firmware_management_protocol, &efi_fmp_fit, NULL)
EFI: Call: efi_install_multiple_protocol_interfaces( &efi_root, &efi_guid_firmware_management_protocol, &efi_fmp_raw, NULL)
EFI: Entry efi_install_multiple_protocol_interfaces(00000000fbfec648)
EFI: Call: efi_install_protocol_interface( handle, protocol, EFI_NATIVE_INTERFACE, protocol_interface)
EFI: Entry efi_install_protocol_interface(00000000fbfec648, 86c77a67-0b97-4633-a187-49104d0685c7, 0, 00000000fbfa6f18)
EFI: handle 00000000fbaf8520
EFI: Exit: efi_install_protocol_interface: 2
EFI: 2 returned by efi_install_protocol_interface( handle, protocol, EFI_NATIVE_INTERFACE, protocol_interface)
EFI: Exit: efi_install_multiple_protocol_interfaces: 2
EFI: 2 returned by efi_install_multiple_protocol_interfaces( &efi_root, &efi_guid_firmware_management_protocol, &efi_fmp_raw, NULL)
Command failed, result=1
To fix this issue, pass the handle local var which is set NULL right
before installing efi_fmp_raw as same as the installing efi_fmp_fit.
(In both cases, the local reference to the handle will be just discarded)
Signed-off-by: Masami Hiramatsu <masami.hiramatsu@linaro.org>
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
According to chapter 7.1 "Event, Timer, and Task Priority Services"
TPL_HIGH_LEVEL should not be exposed to applications and drivers.
According to the discussion with EDK II contributors this implies that
CreateEvent() shall not allow to create events with TPL_HIGH_LEVEL.
Cc: Samer El-Haj-Mahmoud <Samer.El-Haj-Mahmoud@arm.com>
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Acked-by: Samer El-Haj-Mahmoud <Samer.El-Haj-Mahmoud@arm.com>
Brackets '[' need to be escaped to avoid a build warning
lib/efi_loader/efi_image_loader.c:223:
WARNING: Inline strong start-string without end-string.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Masahisa Kojima <masahisa.kojima@linaro.org>
If we want to address partition 15 of virtio block device 11, we have to
write:
virtio b:f
When calling sprintf() we must use %x for the device and partition numbers.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
"TCG PC Client Platform Firmware Profile Specification"
requires to measure every attempt to load and execute
a OS Loader(a UEFI application) into PCR[4].
This commit adds the PE/COFF image measurement, extends PCR,
and appends measurement into Event Log.
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Tested-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Masahisa Kojima <masahisa.kojima@linaro.org>
Replace CONFIG_HASH_CALCULATE by CONFIG_HASH
Fix conversions between pointers and u64.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
The hash_calculate() symbol is provided by hash-checksum.c. It depends
on hash_progressive_lookup_algo(), provided when CONFIG_HASH=y.
The issue is that hash_calculate() is used by the efi_loader,
irregardless of CONFIG_FIT_SIGNATURE. As pointed out in
commit 87316da05f ("lib: introduce HASH_CALCULATE option"),
enabling hash_calculate() based on CONFIG_FIT_SIGNATURE is incorrect.
To resolve this, use CONFIG_HASH as the compile switch for
hash-checksum.c. This ensures that all dependencies are compiled, and
is the most natural Kconfig to use.
There is the issue of having to 'select HASH' in a couple of places
that already 'select SHA256'. This is a deeper problem with how hashes
are organized, and fixing it is beyonf the scope of this change.
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Acked-by: Masahisa Kojima <masahisa.kojima@linaro.org>
When we think of Kconfig, we usually think of features that we like
to enable or not. Ideally, we wouldn't use Kconfig to fix a build
issue, although sometimes it might make sense. With Kconfig it's hard
to guarantee that the fix is universal. We can only say that it works
for the set of tested configurations. In the majority of cases, it's
preferable to let the linker figure things out for us.
The reverted commit attempted to fix a build issue by adding an
invisible Kconfig option. This is wrong in several ways:
It invents a new Kconfig variable when CONFIG_HASH already
exists for the same purpose.
Second, hash-checksum.c makes use of the hash_progressive_lookup_algo()
symbol, which is only provided with CONFIG_HASH, but this dependency
was not expressed in the reverted patch.
It feels like Kconfig is turning into a listing of all available
source files, and a buffet to 'select' which ones to compile. The
purpose of this revert is to enable the next change to make use of
CONFIG_HASH instead of adding to Kconfig.
This reverts commit 87316da05f.
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Acked-by: Masahisa Kojima <masahisa.kojima@linaro.org>
Coverity reported 3 warnings on the current code.
CID 331856, 331855, 331854 on the latest scan.
Fix the rest of the warnings by initializing the variables before
passing them to tpm2_get_pcr_info().
In order to avoid future warnings and errors initialize them to 0 within
the function as well, since the values are always OR'ed after querying the
hardware.
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Compiling with -Wextra produces a number of (harmless) warnings for the EFI
TCG2 protocol. Let's fix those in case we ever enable the flag on the EFI
subsystem
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Before this patch efi_dp_from_name() only accommodated a maximum file path
length of 31 characters. This leads to boot failures due to file name
truncation.
Allow arbitrary path lengths.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
This is preparation for PE/COFF measurement support.
PE/COFF image hash calculation is same in both
UEFI Secure Boot image verification and measurement in
measured boot. PE/COFF image parsing functions are
gathered into efi_image_loader.c, and exposed even if
UEFI Secure Boot is not enabled.
This commit also adds the EFI_SIGNATURE_SUPPORT option
to decide if efi_signature.c shall be compiled.
Signed-off-by: Masahisa Kojima <masahisa.kojima@linaro.org>
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Configuring a system with CONFIG_EFI_CAPSULE_AUTHENTICATE=y but without a
method to retrieve the public key data is a misconfiguration. We should get
a build failure for it. Therefore remove the weak efi_get_public_key_data()
implementation.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Build error occurs when CONFIG_EFI_SECURE_BOOT or
CONFIG_EFI_CAPSULE_AUTHENTICATE is enabled,
because hash-checksum.c is not compiled.
Since hash_calculate() implemented in hash-checksum.c can be
commonly used aside from FIT image signature verification,
this commit itroduces HASH_CALCULATE option to decide
if hash-checksum.c shall be compiled.
Signed-off-by: Masahisa Kojima <masahisa.kojima@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
EFI_TCG2 depends not only on TPMv2 but also on the underlying algorithms.
So select the missing SHA1, SHA256, SHA384 and SHA512 we currently support
Reported-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Add 'default y'.
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Up to now we are stopping the EFI subsystem if a TPMv2 exists but the
protocol fails to install. Now that we've switched the config to 'default
y' the sandbox TPM fails, since it doesn't support all the required
capabilities of the protocol.
Not installing the protocol is not catastrophic. If the protocol fails
to install the PCRs will never be extended to the expected values, so
some other entity later in the boot flow will eventually figure it out
and take the necessary actions.
While at it fix a corner case were the user can see an invalid error
message when the protocol failed to install. We do have a tcg2_uninit()
which we call when the protocol installation fails. There are cases though
that this might be called before the configuration table is installed (e.g
probing the TPM for capabilities failed). In that case the user will see
"Failed to delete final events config table". So stop printing it since it's
not an actual failure , simply because the config table was never installed
in the first place.
In order to stop printing it make efi_init_event_log() and create_final_event()
cleanup themselves and only call tcg2_uninit() when the protocol installation
fails.
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Instead of just failing, clean up the installed config table and
EventLog memory if logging an s-crtm event fails during the protocol
installation
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Eliminate label 'out:' by using return.
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
efi_init_event_log() calls tcg2_uninit() in case of failure.
We can skip that since the function is called on efi_tcg2_register()
which also cleans up if an error occurs
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
This is same issue as https://bugzilla.redhat.com/show_bug.cgi?id=1733817,
but that fix was wrongly partial reverted.
When reading a directory, EFI_BUFFER_TOO_SMALL should be returned when
the supplied buffer is too small, so a use-case is to call
EFI_FILE_PROTOCOL.Read() with *buffer_size=0 and buffer=NULL to
obtain the needed size before doing the actual read.
So remove the check only for directory reading, file reading already
do the check by itself.
Fixes: db12f518edb0("efi_loader: implement non-blocking file services")
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Cc: Stefan Sørensen <stefan.sorensen@spectralink.com>
Tested-by: Peter Robinson <pbrobinson@gmail.com>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
The current capsule authentication code checks if the environment
variable capsule_authentication_enabled is set, for authenticating the
capsule. This is in addition to the check for the config symbol
CONFIG_EFI_CAPSULE_AUTHENTICATE. Remove the check for the environment
variable. The capsule will now be authenticated if the config symbol
is set.
Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
Reviwed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Building 32bit boards with the TCG2 protocol enabled leads to a build
warning due to a missing conversion.
lib/efi_loader/efi_tcg2.c:774:27:
error: cast to pointer from integer of different size
[-Werror=int-to-pointer-cast]
774 | ret = tcg2_create_digest((u8 *)data_to_hash, data_to_hash_len,
| ^
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
In case of failure at efi_get_variable_int("BootOrder"), we should
skip examining boot option variables and return an appropriate error
code which is the one the function returned.
Fixes: CID 331153 Code maintainability issues (UNUSED_VALUE)
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Indicated by Coverity Scan CID 331147
The ESRT was being refreshed in situations where the UpdateCapsule
procedure failed. In that scenario:
1) the ESRT refresh was superfluous.
2) a failed ESRT refresh return code overwrites the UpdateCapsule error
return code.
This commit ensures that the ESRT is only refreshed when the
UpdateCapsule performs successfully.
CC: Heinrich Schuchardt <xypron.glpk@gmx.de>
CC: Sughosh Ganu <sughosh.ganu@linaro.org>
CC: AKASHI Takahiro <takahiro.akashi@linaro.org>
CC: Tom Rini <trini@konsulko.com>
CC: Andre Przywara <andre.przywara@arm.com>
CC: nd@arm.com
Signed-off-by: Jose Marinho <jose.marinho@arm.com>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Bumping the digest list count, for all supported algorithms, can be
calculated outside of the individual switch statements. So let's do that
for every loop iteration instead and simplify the code a bit.
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
To avoid diverging function definitions we need to include efi_loader.h.
Fixes: fe179d7fb5 ("efi_loader: Add size checks to efi_create_indexed_name()")
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Variable "final" will have SHA512 digest, but currently
the array size is not sufficient. Let's fix it.
Signed-off-by: Masahisa Kojima <masahisa.kojima@linaro.org>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
If realloc() fails, we should free the old buffer.
Fixes: c74cd8bd08: ("efi_loader: capsule: add capsule_on_disk support")
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Remove function invocations using the EFI_CALL macro for those
functions that do not have an EFI_ENTRY call in their definition. Such
functions can use u-boot api's which rely on u-boot global data(gd)
pointer. The Arm and RiscV architectures maintain a separate gd
pointer, one for u-boot, and a separate gd for the efi application.
Calling a function through the EFI_CALL macro changes the gd pointer
to that used for the efi application, with u-boot gd being
unavailable. Any function then trying to dereference u-boot's gd will
result in an abort.
Fix this issue by removing the EFI_CALL macro for all of such
functions which do not begin by an EFI_ENTRY function call.
Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Although ptr arithmetics are allowed with extensions in gcc, they
are not allowed by the C spec. So switch to (void *)(uintptr_t) instead
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Fix the build warning when building for 32 bit systems by using the
length modifier for size_t.
lib/efi_loader/efi_esrt.c: In function ‘efi_esrt_populate’:
include/efi_loader.h:126:8: warning: format ‘%ld’ expects argument of type ‘long int’, but argument 8 has type ‘size_t’ {aka ‘unsigned int’} [-Wformat=]
Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Enable building of the crypto helper functions used during capsule
authentication by selecting IMAGE_SIGN_INFO.
Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
get_var() is defined statically in efi_bootmgr.c and doesn't properly
check a buffer allocation. Remove it completely and use the exported
function from efi_var_common.c that does the same thing
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
In the devicepath node to text conversion for Uart nodes a break statement
is missing.
Indicated by Coverity Scan CID 330038
Fixes: 62df6e9c99 ("efi_loader: Uart device path")
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
We recently added a common function for calculating file size,
instead of copy pasting the code around. Switch one of the
occurences over to the common function
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviwed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
TCG PC Client Platform Firmware Profile Spec mandates that an S-CRTM
event for the version identifier using the event type EV_S_CRTM_VERSION
must be measured.
So since we are trying to add more conformance into U-Boot, let's add
the event using U_BOOT_VERSION_STRING, extend PCR[0] accordingly and log
it in the EventLog
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Current code doesn't free the efi allocated memory in case the protocol
failed to install
Fixes: c8d0fd5825 ("efi_loader: Introduce eventlog support for TCG2_PROTOCOL")
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
The ESRT is initialised during efi_init_objlist after
efi_initialize_system_table().
The ESRT is recreated from scratch at the following events:
- successful UpdateCapsule;
- FMP instance install.
The code ensures that every ESRT entry has a unique fw_class value.
Limitations:
- The ESRT is not updated if an FMP instance is uninstalled;
- the fields image_type and flags are in the current implementation left
undefined. Setting these values will require a per-platform function
that returns the image_type/flags as a function of the image fw_class.
CC: Heinrich Schuchardt <xypron.glpk@gmx.de>
CC: Sughosh Ganu <sughosh.ganu@linaro.org>
CC: AKASHI Takahiro <takahiro.akashi@linaro.org>
CC: Ilias Apalodimas <ilias.apalodimas@linaro.org>
CC: Andre Przywara <andre.przywara@arm.com>
CC: Alexander Graf <agraf@csgraf.de>
CC: nd@arm.com
Signed-off-by: Jose Marinho <jose.marinho@arm.com>
Remove two EFI_CALL() indirections.
Move ESRT GUID in efidebug's list of GUIDs.
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Up to now we install EFI_LOAD_FILE2_PROTOCOL to load an initrd
unconditionally. Although we correctly return various EFI exit codes
depending on the file status (i.e EFI_NO_MEDIA, EFI_NOT_FOUND etc), the
kernel loader, only falls back to the cmdline interpreted initrd if the
protocol is not installed.
This creates a problem for EFI installers, since they won't be able to
load their own initrd and continue the installation. It also makes the
feature hard to use, since we can either have a single initrd or we have
to recompile u-boot if the filename changes.
So let's introduce a different logic that will decouple the initrd
path from the config option we currently have.
When defining a UEFI BootXXXX we can use the filepathlist and store
a file path pointing to our initrd. Specifically the EFI spec describes:
"The first element of the array is a device path that describes the device
and location of the Image for this load option. Other device paths may
optionally exist in the FilePathList, but their usage is OSV specific"
When the EFI application is launched through the bootmgr, we'll try to
interpret the extra device path. If that points to a file that exists on
our disk, we'll now install the load_file2 and the efi-stub will be able
to use it.
This opens up another path using U-Boot and defines a new boot flow.
A user will be able to control the kernel/initrd pairs without explicit
cmdline args or GRUB.
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
A following patch introduces a different logic for loading initrd's
based on the EFI_LOAD_FILE2_PROTOCOL.
Since similar logic can be applied in the future for other system files
(i.e DTBs), let's add some helper functions which will retrieve and
parse file paths stored in EFI variables.
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
On the following patches we allow for an initrd path to be stored in
Boot#### variables. Specifically we encode in the FIlePathList[] of
the EFI_LOAD_OPTIONS for each Boot#### variable.
The FilePathList[] array looks like this:
kernel - 0xff - VenMedia(initrd GUID) - initrd1 - 0x01 initrd2 - 0xff
So let's add the relevant functions to concatenate and retrieve a device
path based on a Vendor GUID.
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reformat function descriptions.
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
