Commit graph

86 commits

Author SHA1 Message Date
Ilias Apalodimas
77bb14758d efi_loader: avoid adding variables twice
When the efi subsystem starts we restore variables that are both in a
file or stored into the .efi_runtime section of U-Boot.  However once
a variable gets created or changed the preseeded entries will end up in
the file.  As a consequence on the next boot we will end up adding
identical variable entries twice.

Fix this by checking if the to be inserted variable already exists.
Also swap the restoration order and start with the file instead of the
builtin variables,  so a user can replace the preseeded ones if needed.

Tested-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
2022-12-29 10:51:50 +01:00
Simon Glass
156ccbc3c4 efi: Use 16-bit unicode strings
At present we use wide characters for unicode but this is not necessary.
Change the code to use the 'u' literal instead. This helps to fix build
warnings for sandbox on rpi.

Signed-off-by: Simon Glass <sjg@chromium.org>
Suggested-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2022-02-03 12:16:01 -05:00
Heinrich Schuchardt
d47671c631 efi_loader: treat UEFI variable name as const
UEFI variable names are typically constants and hence should be defined as
const. Unfortunately some of our API functions do not define the parameters
for UEFI variable names as const. This requires unnecessary conversions.

Adjust parameters of several internal functions to tre UEFI variable names
as const.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
2021-10-25 21:13:06 +02:00
Heinrich Schuchardt
b191aa429e efi_loader: efi_auth_var_type for AuditMode, DeployedMode
Writing variables AuditMode and DeployedMode serves to switch between
Secure Boot modes. Provide a separate value for these in efi_auth_var_type.

With this patch the variables will not be read from from file even if they
are marked as non-volatile by mistake.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
2021-09-04 12:03:57 +02:00
Heinrich Schuchardt
9ef82e2947 efi_loader: don't load signature database from file
The UEFI specification requires that the signature database may only be
stored in tamper-resistant storage. So these variable may not be read
from an unsigned file.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
2021-09-04 12:03:57 +02:00
Sughosh Ganu
201b8068f3 efi_loader: Make the pkcs7 header parsing function an extern
The pkcs7 header parsing functionality is pretty generic, and can be
used by other features like capsule authentication. Make the function
an extern, also changing it's name to efi_parse_pkcs7_header

Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
2020-12-31 14:41:31 +01:00
Heinrich Schuchardt
ab02c3fec4 efi_loader: non-volatile variable not deleted from file
When deleting a non-volatile variable it was deleted from memory but the
deletion was not persisted to the file system.

SetVariable() may be called with attributes == 0 to delete a variable. To
determine if the deletion shall be persisted we have to consider the
non-volatile flag in the attributes of the deleted variable and not the
value passed in the call parameter.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-11-09 17:28:17 +01:00
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
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
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
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
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
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
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
3a92f85f21 efi_loader: rtc_mktime() called twice
Don't call rtc_mktime() twice with the same argument in
efi_variable_authenticate().

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-03 18:03:47 +02:00
Heinrich Schuchardt
cb7116030a efi_loader: time based authentication
When overwriting an existing time base authenticated variable we should
compare to the preceding time value and not to the start of the epoch.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-03 18:03:41 +02:00
Heinrich Schuchardt
33f183f68b efi_loader: add missing validation of timestamp
The UEFI specification requires that when UEFI variables are set using time
based authentication we have to check that unused fields of the timestamp
are zero

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-03 18:03:41 +02:00
AKASHI Takahiro
ce3c3865b0 efi_loader: variable: replace debug to EFI_PRINT
Just for style consistency, replace all the uses of debug() to
EFI_PRINT in efi_variable.c.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-03 18:00:27 +02:00
Heinrich Schuchardt
e4c1c48eeb efi_loader: fix incorrect use of EFI_EXIT()
efi_get_variable_common() does not use EFI_ENTRY(). So we should not use
EFI_EXIT() either.

Fixes: 767f6eeb01 ("efi_loader: variable: support variable authentication")
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-06-29 11:56:10 +02:00
Heinrich Schuchardt
d80dd9e785 efi_loader: size of secure boot variables
The variables SetupMode, AuditMode, DeployedMode are explicitly defined as
UINT8 in the UEFI specification. The type of SecureBoot is UINT8 in EDK2.

Use variable name secure_boot instead of sec_boot for the value of the
UEFI variable SecureBoot.

Avoid abbreviations in function descriptions.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-06-24 16:50:15 +02:00
Heinrich Schuchardt
915f15ac57 efi_loader: type of efi_secure_mode
Variable efi_secure_mode is meant to hold a value of enum efi_secure_mode.
So it should not be defined as int but as enum efi_secure_mode.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-06-24 16:50:15 +02:00
AKASHI Takahiro
a4292eccfd efi_loader: signature: move efi_guid_cert_type_pkcs7 to efi_signature.c
The global variable, efi_guid_cert_type_pkcs7, will also be used in
efi_image_loader.c in a succeeding patch so as to correctly handle
a signature type of authenticode in signed image.

Meanwhile, it is currently defined in efi_variable.c. Once some secure
storage solution for UEFI variables is introduced, efi_variable.c may
not always be compiled in.

So move the definition to efi_signature.c as a common place.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-06-03 17:19:19 +02:00
Pragnesh Patel
9de6ce807e efi_loader: Remove unnecessary debug
Remove unnecessary debug() from efi_set_variable_common().
native_name is NULL, so there is no meaning to print it.

Signed-off-by: Pragnesh Patel <pragnesh.patel@sifive.com>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-05-21 10:00:17 +02:00
Simon Glass
cd93d625fd common: Drop linux/bitops.h from common header
Move this uncommon header out of the common header.

Signed-off-by: Simon Glass <sjg@chromium.org>
2020-05-18 21:19:23 -04:00
Simon Glass
0914011310 command: Remove the cmd_tbl_t typedef
We should not use typedefs in U-Boot. They cannot be used as forward
declarations which means that header files must include the full header to
access them.

Drop the typedef and rename the struct to remove the _s suffix which is
now not useful.

This requires quite a few header-file additions.

Signed-off-by: Simon Glass <sjg@chromium.org>
2020-05-18 18:36:55 -04:00
Simon Glass
ba06b3c50b common: Drop uuid.h from common header
Move this uncommon header out of the common header.

Signed-off-by: Simon Glass <sjg@chromium.org>
2020-05-18 14:53:28 -04:00
AKASHI Takahiro
b433acbb81 efi_loader: variable: check a return value of uuid__str_to_bin()
The only error case is that a given UUID is in wrong format.
So just return EFI_INVALID_PARAMETER here.

Reported-by: Coverity (CID 300333)
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-05-09 09:30:27 +02:00
Patrick Wildt
9ad15227bb efi_loader: efi_variable_parse_signature() returns NULL on error
efi_variable_parse_signature() returns NULL on error, so IS_ERR()
is an incorrect check.  The goto err leads to pkcs7_free_message(),
which works fine on a NULL ptr.

Signed-off-by: Patrick Wildt <patrick@blueri.se>
Reviewed-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
2020-05-07 18:23:16 +02:00
Heinrich Schuchardt
306bf6e7ff efi_loader: do not unnecessarily use EFI_CALL()
There is no need to call efi_get_variable() instead of
efi_get_variable_common(). So let's use the internal function.

Move forward declarations to the top of the file.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-05-07 18:23:16 +02:00
Heinrich Schuchardt
3fdff6be40 efi_loader: error handling in efi_set_variable_common().
Fix unreachable code. Free memory on error.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-05-07 18:23:16 +02:00
Heinrich Schuchardt
30f92ce9d5 efi_loader: correct comments for efi_status_t
EFI_STATUS is unsigned (UINTN). Hence it cannot be negative.
Correct comments for 'Return:'.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-05-04 12:26:11 +02:00
Heinrich Schuchardt
bb0e585c71 efi_loader: eliminate efi_set_(non)volatile_variable
Eliminate superfluous functions efi_set_volatile_variable() and
efi_set_nonvolatile_variable().

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-05-04 12:26:11 +02:00
Heinrich Schuchardt
c08cac0edc efi_loader: eliminate efi_get_(non)volatile_variable
Eliminate superfluous functions efi_get_volatile_variable() and
efi_get_nonvolatile_variable().

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-05-04 12:26:11 +02:00
AKASHI Takahiro
f0ff75f249 efi_loader: factor out the common code from efi_transfer_secure_state()
efi_set_secure_stat() provides the common code for each stat transition
caused by efi_transfer_secure_state().

Suggested-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Correct description of return value.
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-05-04 12:26:11 +02:00
AKASHI Takahiro
e3f5c9cb0f lib/crypto, efi_loader: move some headers to include/crypto
Pkcs7_parse.h and x509_parser.h are used in UEFI subsystem, in particular,
secure boot. So move them to include/crypto to avoid relative paths.

Suggested-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Don't include include x509_parser.h twice.
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-05-04 12:26:11 +02:00
AKASHI Takahiro
8353516f4a efi_loader: variable: add VendorKeys variable
The following variable is exported as UEFI specification defines:
VendorKeys: whether the system is configured to use only vendor-provided
	    keys or not
The value will have to be modified if a platform has its own way of
initializing signature database, in particular, PK.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
2020-04-16 08:12:46 +02:00
AKASHI Takahiro
434ffb6422 efi_loader: variable: add secure boot state transition
UEFI specification defines several global variables which are related to
the current secure boot state. In this commit, those values will be
maintained according to operations. Currently, AuditMode and DeployedMode
are defined but not implemented.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
2020-04-16 08:12:46 +02:00
AKASHI Takahiro
767f6eeb01 efi_loader: variable: support variable authentication
With this commit, EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS
is supported for authenticated variables and the system secure state
will transfer between setup mode and user mode as UEFI specification
section 32.3 describes.

Internally, authentication data is stored as part of authenticated
variable's value. It is nothing but a pkcs7 message (but we need some
wrapper, see efi_variable_parse_signature()) and will be validated by
efi_variable_authenticate(), hence efi_signature_verify_with_db().

Associated time value will be encoded in "{...,time=...}" along with
other UEFI variable's attributes.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
2020-04-16 08:12:46 +02:00
Heinrich Schuchardt
7a4e717b9c efi_loader: definition of GetNextVariableName()
'vendor' is both an input and an output parameter. So it cannot be
constant.

Fixes: 0bda81bfdc ("efi_loader: use const efi_guid_t * for variable services")
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-03-22 18:38:02 +01:00
Heinrich Schuchardt
4d7f5af841 efi_loader: correct reported length in GetNextVariable()
The runtime service GetNextVariable() returns the length of the next
variable including the closing 0x0000. This length should be in bytes.

Comparing the output of EDK2 and U-Boot shows that this is currently not
correctly implemented:

EDK2:
OsIndicationsSupported: 46
PlatformLang: 26
PlatformLangCodes: 36

U-Boot:
OsIndicationsSupported: 23
PlatformLang: 13
PlatformLangCodes: 18

Provide correct length in GetNextVariable().

Fixes: d99a87f84b ("efi_loader: implement GetNextVariableName()")
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-03-22 11:06:23 +01:00
Heinrich Schuchardt
f0b0f7fe0e efi_loader: description of efi_variable.c
Correct the file description.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-03-22 11:06:23 +01:00