Do not use data from the loaded image object after deleting it.

Fixes: 126a43f15b36 ("efi_loader: unload applications upon Exit()")
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

Add the missing description of some fields of struct efi_loaded_image_obj.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

Since U-boot EFI implementation is getting richer it makes sense to
add support for EFI_TCG2_PROTOCOL taking advantage of any hardware TPM
available on the device.

This is the initial implementation of the protocol which only adds
support for GetCapability(). It's limited in the newer and safer
TPMv2 devices.

Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Acked-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

When calling ExitBootServices during out unit tests we should not detach
devices as we need console output for runtime tests.

Fixes: 529441ca89b1 ("efi_loader: Disable devices before handing over control")
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

This function will be used from several places in UEFI subsystem
to generate some specific form of utf-16 variable name.
For example, L"Capsule0001"

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Move function to separate module.
Use char * as argument instead of u16 *.
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

Having an EFI_RNG_PROTOCOL without a backing RNG device leads to failure
to boot Linux 5.8.

Only install the EFI_RNG_PROTOCOL if we have a RNG device.

Reported-by: Scott K Logan <logans@cottsay.net>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

We need to check that device paths provided via UEFI variables are not
malformed.

Provide function efi_dp_check_length() to check if a device path has an
end node within a given number of bytes.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

Under the current implementation, all the signatures, if any, in
a signed image must be verified before loading it.

Meanwhile, UEFI specification v2.8b section 32.5.3.3 says,
    Multiple signatures are allowed to exist in the binary’s certificate
    table (as per PE/COFF Section “Attribute Certificate Table”). Only
    one hash or signature is required to be present in db in order to pass
    validation, so long as neither the SHA-256 hash of the binary nor any
    present signature is reflected in dbx.

This patch makes the semantics of signature verification compliant with
the specification mentioned above.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reported-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

In this commit, efi_signature_verify(with_sigdb) will be re-implemented
using pcks7_verify_one() in order to support certificates chain, where
the signer's certificate will be signed by an intermediate CA (certificate
authority) and the latter's certificate will also be signed by another CA
and so on.

What we need to do here is to search for certificates in a signature,
build up a chain of certificates and verify one by one. pkcs7_verify_one()
handles most of these steps except the last one.

pkcs7_verify_one() returns, if succeeded, the last certificate to verify,
which can be either a self-signed one or one that should be signed by one
of certificates in "db". Re-worked efi_signature_verify() will take care
of this step.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>

Up to now we used the value of the bootargs environment variable as load
options in the boot manager. This is not correct. The data has to be taken
from the Boot#### variable.

Let the boot manager copy the optional data of the EFI_LOAD_OPTION as load
options to the loaded image protocol.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>