Commit graph

858 commits

Author SHA1 Message Date
Heinrich Schuchardt
578d7cc8fa efi_loader: remove duplicate image size check
The image size is checked in efi_load_pe(). Avoid checking it twice.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-09-06 21:21:41 +02:00
Heinrich Schuchardt
0f7878b853 efi_loader: error message if image not authenticated
Currently if the bootefi command fails due to missing authentication, the
user gets no feedback.

Write a log message 'Image not authenticated' if LoadImage() fails due to
missing authentication.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-09-06 21:21:41 +02:00
Heinrich Schuchardt
24586059d3 efi_loader: log function in image loader
Use log_err() for error messages.
Replace debug() by EFI_PRINT().

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-09-06 21:21:41 +02:00
Heinrich Schuchardt
15d8f008dc efi_loader: validate device path length in boot manager
Bootxxxx variables are provided by the user and therefore cannot be
trusted. We have to validate them before usage.

A device path provided by a Bootxxxx variable must have an end node within
the indicated device path length.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-08-24 16:37:53 +02:00
Heinrich Schuchardt
5cad4a3093 efi_loader: efi_dp_check_length()
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>
2020-08-24 16:37:53 +02:00
Heinrich Schuchardt
f03a879d67 efi_loader: ResetSystem() should not hang
If ResetSystem() is not implemented at runtime, it should return instead
of hanging in an endless loop. This allows the operating system to reset
the system by other means as Linux does. It also matches what EDK II
suggests in comments for functions ResetShutdown() and ResetWarm() in
OvmfPkg/Library/ResetSystemLib/ResetSystemLib.c.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-08-24 16:37:53 +02:00
AKASHI Takahiro
52956e535e efi_loader: signature: correct a behavior against multiple signatures
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>
2020-08-14 12:28:25 +02:00
AKASHI Takahiro
f68a6d5835 efi_loader: variable: fix secure state initialization
Under the new file-based variable implementation, the secure state
is always and falsely set to 0 (hence, the secure boot gets disabled)
after the reboot even if PK (and other signature database) has already
been enrolled in the previous boot.

This is because the secure state is set up *before* loading non-volatile
variables' values from saved data.

This patch fixes the order of variable initialization and secure state
initialization.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Fixes: 5f7dcf079d ("efi_loader: UEFI variable persistence")
2020-08-13 22:37:42 +02:00
AKASHI Takahiro
1115edd846 efi_loader: signature: rework for intermediate certificates support
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>
2020-08-13 22:37:36 +02:00
AKASHI Takahiro
0658bb29b0 efi_loader: variable: keep temporary buffer during the authentication
This is a bug fix; Setting an authenticated variable may fail due to
a memory corruption in the authentication.

A temporary buffer will, if needed, be allocated to parse a variable's
authentication data, and some portion of buffer, specifically signer's
certificates, will be referenced by efi_signature_verify().

So the buffer should be kept valid until the authentication process
is finished.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Tested-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-08-13 22:37:36 +02:00
Heinrich Schuchardt
0ad64007fe efi_loader: set load options in boot manager
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>
2020-08-08 19:03:24 +02:00
Heinrich Schuchardt
1064d04920 efi_loader: factor out efi_set_load_options()
The bootefi bootmgr command has to set the load options for a loaded image
from the value of BootXXXX variable. If the boot manager is not used, the
value is set from the environment variable bootargs (or efi_selftest).

Factor out a common function efi_set_load_options().

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-08-08 19:03:24 +02:00
AKASHI Takahiro
dd92aad81c efi_loader: add copyright notice
Some amount of code was moved/derived from efi_variable.c regarding
UEFI secure boot, in particluar in the commit 012c56ac76 ("efi_loader:
restructure code for TEE variables").
So add the orignal author's copyright notice.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-08-08 19:03:24 +02:00
Heinrich Schuchardt
74b869bae7 efi_loader: use CONFIG_STACK_SIZE in the UEFI sub-system
The Kconfig symbol CONFIG_STACK_SIZE is used both by ARM and Microblaze
with the same meaning. Move it to menu 'General setup' so that we can use
it for all architectures.

Use the value of CONFIG_STACK_SIZE instead of a hard coded 16 MiB value for
reserving memory in the UEFI sub-system.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-08-01 11:58:23 +02:00
Ilias Apalodimas
e01aed47d6 efi_loader: Enable run-time variable support for tee based variables
We recently added functions for storing/restoring variables
from a file to a memory backed buffer marked as __efi_runtime_data
commit f1f990a8c9 ("efi_loader: memory buffer for variables")
commit 5f7dcf079d ("efi_loader: UEFI variable persistence")

Using the same idea we now can support GetVariable() and GetNextVariable()
on the OP-TEE based variables as well.

So let's re-arrange the code a bit and move the commmon code for
accessing variables out of efi_variable.c. Create common functions for
reading variables from memory that both implementations can use on
run-time. Then just use those functions in the run-time variants of the
OP-TEE based EFI variable implementation and initialize the memory
buffer on ExitBootServices()

Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-08-01 11:57:41 +02:00
Ilias Apalodimas
db94dfbd52 efi_loader: Trim output buffer size correctly for tee variables
The current code does not trim the output buffer correctly.
In fact it doesn't trim the buffer at all, since it calculates a wrong
value for it, which isn't even applied.
So let's remove the unused temporary size variable and trim the buffer
correctly.
Since we are editing efi_get_next_variable_name_int(), fix an indentation
error along the way.

Fixes: f042e47e8f ("efi_loader: Implement EFI variable handling via OP-TEE")
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>

Remove superfluous conversion to (u8 *) for memcpy argument.
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-08-01 11:57:41 +02:00
Heinrich Schuchardt
af457cfca9 efi_loader: use logging for block device messages
Use logging instead of printf() for messages occurring when scanning block
devices during the initialization of the UEFI sub-system.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-22 12:32:42 +02:00
Heinrich Schuchardt
e7d64065cb efi_loader: document efi_save_gd(), efi_restore_gd()
Provide function descriptions for efi_save_gd() and efi_restore_gd().

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-22 12:32:42 +02:00
Stefan Sørensen
1ef1cf1f93 efi_loader: loosen buffer parameter check in efi_file_read
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_read with *buffer_size=0 and buffer=NULL to obtain the needed
size before doing the actual read.

So move the buffer!=NULL check to after the buffer size has been checked.

This fix allows the Redhat shim fallback to run and e.g. Fedora 32 now
boots out of the box.

Signed-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-22 12:32:41 +02:00
Ilias Apalodimas
9b87d4429c efi_loader: Check for the native OP-TEE result on mm_communicate calls
Currently we only check for the return value of tee_invoke_func().
Although OP-TEE and StMM will correctly set param[1].u.value.a and we'll
eventually return an error, the correct thing to do is check for the
OP_TEE return code as well.
So let's check for that and move tee_shm_free() and tee_close_session()
before exiting with an error to make sure we always clear the registered
memory.

Fixes: f042e47e8f ("efi_loader: Implement EFI variable handling via OP-TEE")
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Use EFI_DEVICE_ERROR for TEE communication problems.
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-22 12:32:41 +02:00
Ilias Apalodimas
5d1f79ba43 efi_loader: Rename and correct values for ARM_SMC_MM_*
Instead of adding the definition for the specific MM SVC used in
StandAloneMM we added the one used in the standard SMC calls.
So change the value from -4 to -5 to match the correct one defined in
EDK2 and rename them to avoid future confusion

Fixes 23a397d2e2: ("efi_loader: Add headers for EDK2 StandAloneMM communication")
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-22 12:32:41 +02:00
Heinrich Schuchardt
ebbad02c1b efi_loader: don't use memmove() in efi_var_mem_del()
efi_var_mem_del() is in __efi_runtime because it would be needed for a
runtime implementation of SetVariable(). memmove() is not in __efi_runtime.
So we should not use it in efi_var_mem_del().

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-22 12:32:41 +02:00
Heinrich Schuchardt
01fa922bbb efi_loader: efi_current_var after SetVirtualAddressMap
Variable efi_current_var is a pointer to a physical memory address that
becomes invalid after SetVirtualAddressMap(). Instead of converting it via
ConvertPointer() simply set it to NULL.

Fixes: b02a707152 ("efi_loader: enable UEFI variables at runtime")
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-22 12:32:41 +02:00
Heinrich Schuchardt
7dda16343d efi_loader: pre-seed UEFI variables
Include a file with the initial values for non-volatile UEFI variables
into the U-Boot binary. If this variable is set, changes to variable PK
will not be allowed.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-16 12:37:02 +02:00
Heinrich Schuchardt
99bfab8b58 efi_loader: identify PK, KEK, db, dbx correctly
To determine if a varible is on the of the authentication variables
PK, KEK, db, dbx we have to check both the name and the GUID.

Provide a function converting the variable-name/guid pair to an enum and
use it consistently.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-16 12:37:02 +02:00
Heinrich Schuchardt
be66b89da3 efi_loader: configuration of variables store
The file based and the OP-TEE based UEFI variable store are mutually
exclusive. Define them as choice options in Kconfig.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-16 12:37:02 +02:00
Heinrich Schuchardt
1a7b0f6e4e efi_loader: update secure state
Update the UEFI secure state when variable 'PK' is updated in the TEE
variables implementation.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
2020-07-16 12:37:02 +02:00
Heinrich Schuchardt
012c56ac76 efi_loader: restructure code for TEE variables
When using secure boot functions needed both for file and TEE based UEFI
variables have to be moved to the common code module efi_var_common.c.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-16 12:37:02 +02:00
Ilias Apalodimas
f96744b250 efi_loader: display RO attribute with TEE-backed variables
A previous commit adds support for displaying variables RO flag.
Let's add it on the TEE backed variable storage as well.

Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-16 12:37:02 +02:00
Heinrich Schuchardt
b02a707152 efi_loader: enable UEFI variables at runtime
Enable UEFI variables at runtime.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-11 23:14:17 +02:00
Heinrich Schuchardt
ab7296c99c efi_loader: use memory based variable storage
Saving UEFI variable as encoded U-Boot environment variables does not allow
implement run-time support.

Use a memory buffer for storing UEFI variables.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-11 23:14:17 +02:00
Heinrich Schuchardt
f1f990a8c9 efi_loader: memory buffer for variables
Saving UEFI variable as encoded U-Boot environment variables does not allow
support at runtime.

Provide functions to manage a memory buffer with UEFI variables.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-11 23:14:17 +02:00
Heinrich Schuchardt
b0dd8cb407 efi_loader: new function efi_memcpy_runtime()
Provide a memcpy() function that we can use at UEFI runtime.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-11 23:14:17 +02:00
Heinrich Schuchardt
724d28171e efi_loader: optional pointer for ConvertPointer
If the EFI_OPTIONAL_PTR is set in DebugDisposition, a NULL pointer does not
constitute an invalid parameter.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-11 23:14:17 +02:00
Heinrich Schuchardt
a44d2a2399 efi_loader: export efi_convert_pointer()
We need ConvertPointer() to adjust pointers when implementing  runtime
services within U-Boot.

After ExitBootServices() gd is not available anymore. So we should not use
EFI_ENTRY() and EFI_EXIT().

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-11 23:14:17 +02:00
Heinrich Schuchardt
5f7dcf079d efi_loader: UEFI variable persistence
Persist non-volatile UEFI variables in a file on the EFI system partition.

The file is written whenever a non-volatile UEFI variable is changed after
initialization of the UEFI sub-system.

The file is read during the UEFI sub-system initialization to restore
non-volatile UEFI variables.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-11 23:14:17 +02:00
Heinrich Schuchardt
198bf6418e efi_loader: secure boot flag
In audit mode the UEFI variable SecureBoot is set to zero but the
efi_secure_boot flag is set to true.

The efi_secure_boot flag should match the UEFIvariable SecureBoot.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-11 23:14:17 +02:00
Heinrich Schuchardt
55a830560e efi_loader: read-only AuditMode and DeployedMode
Set the read only property of the UEFI variables AuditMode and DeployedMode
conforming to the UEFI specification.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-11 23:14:17 +02:00
Heinrich Schuchardt
fd7b6730ab efi_loader: value of VendorKeys
According to the UEFI specification the variable VendorKeys is 1 if the
"system is configured to use only vendor-provided keys".

As we do not supply any vendor keys yet the variable VendorKeys must be
zero.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-11 23:14:17 +02:00
Heinrich Schuchardt
37fa7cb045 efi_loader: keep attributes in efi_set_variable_int
Do not change the value of parameter attributes in function
efi_set_variable_int(). This allows to use it later.

Do not use variable attr for different purposes but declare separate
variables (attr and old_attr).

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-11 23:14:17 +02:00
Heinrich Schuchardt
dda8c7163a efi_loader: simplify boot manager
Simplify the implementation of the UEFI boot manager:

* avoid EFI_CALL for SetVariable() and GetVariable()
* remove unnecessary type conversions

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-11 23:14:17 +02:00
Heinrich Schuchardt
dc90e5c491 efi_loader: OsIndicationsSupported, PlatformLangCodes
UEFI variables OsIndicationsSupported, PlatformLangCodes should be read
only.

Avoid EFI_CALL() for SetVariable().

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-11 23:14:16 +02:00
Heinrich Schuchardt
01df8cf336 efi_loader: separate UEFI variable API from implemementation
Separate the remaining UEFI variable API functions GetNextVariableName and
QueryVariableInfo() from internal functions implementing them.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-11 23:14:16 +02:00
Heinrich Schuchardt
f2d2b3a11c efi_loader: prepare for read only OP-TEE variables
We currently have two implementations of UEFI variables:

* variables provided via an OP-TEE module
* variables stored in the U-Boot environment

Read only variables are up to now only implemented in the U-Boot
environment implementation.

Provide a common interface for both implementations that allows handling
read-only variables.

As variable access is limited to very few source files put variable
related definitions into new include efi_variable.h instead of efi_loader.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-11 23:14:16 +02:00
Heinrich Schuchardt
a27c78fddb efi_loader: NULL dereference in efi_convert_pointer
Avoid a possible NULL pointer dereference in efi_convert_pointer().

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-11 23:14:16 +02:00
Heinrich Schuchardt
1047c6e23c efi_loader: fix efi_get_child_controllers()
Don't call calloc(0, ..).
Consider return value of efi_get_child_controllers().

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-11 23:14:16 +02:00
Heinrich Schuchardt
39a75f5af1 efi_loader: wrong printf format in efi_image_parse
Commit 1b6c08548c ("efi_loader: image_loader: replace debug to
EFI_PRINT") leads to a build warning on 32bit systems:

lib/efi_loader/efi_image_loader.c: In function ‘efi_image_parse’:
include/efi_loader.h:123:8: warning: format ‘%lu’ expects argument
of type ‘long unsigned int’, but argument 8 has
type ‘size_t’ {aka ‘unsigned int’} [-Wformat=]

Use %zu for printing size_t.

Fixes: 1b6c08548c ("efi_loader: image_loader: replace debug to
EFI_PRINT")

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-11 23:14:16 +02:00
Ilias Apalodimas
ecb833a0c6 efi_loader: cleanup for tee backed variables
There's 2 variables in efi_get_next_variable_name() checking the size of
the variable name. Let's get rid of the reduntant definition and
simplitfy the code a bit.

Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-11 23:14:16 +02:00
AKASHI Takahiro
7926dfb579 efi_loader: image_loader: add digest-based verification for signed image
In case that a type of certificate in "db" or "dbx" is
EFI_CERT_X509_SHA256_GUID, it is actually not a certificate which contains
a public key for RSA decryption, but a digest of image to be loaded.
If the value matches to a value calculated from a given binary image, it is
granted for loading.

With this patch, common digest check code, which used to be used for
unsigned image verification, will be extracted from
efi_signature_verify_with_sigdb() into efi_signature_lookup_digest(), and
extra step for digest check will be added to efi_image_authenticate().

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
2020-07-11 23:14:15 +02:00
AKASHI Takahiro
11bafb2596 efi_loader: image_loader: verification for all signatures should pass
A signed image may have multiple signatures in
  - each WIN_CERTIFICATE in authenticode, and/or
  - each SignerInfo in pkcs7 SignedData (of WIN_CERTIFICATE)

In the initial implementation of efi_image_authenticate(), the criteria
of verification check for multiple signatures case is a bit ambiguous
and it may cause inconsistent result.

With this patch, we will make sure that verification check in
efi_image_authenticate() should pass against all the signatures.
The only exception would be
  - the case where a digest algorithm used in signature is not supported by
    U-Boot, or
  - the case where parsing some portion of authenticode has failed
In those cases, we don't know how the signature be handled and should
just ignore them.

Please note that, due to this change, efi_signature_verify_with_sigdb()'s
function prototype will be modified, taking "dbx" as well as "db"
instead of outputing a "certificate." If "dbx" is null, the behavior would
be the exact same as before.
The function's name will be changed to efi_signature_verify() once
current efi_signature_verify() has gone due to further improvement
in intermediate certificates support.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
2020-07-11 23:14:15 +02:00