According to the TCG Platform Reset Attack Mitigation Specification (May
15, 2008):
> 5 Interface for UEFI
> 5.1 UEFI Variable
> 5.1.1 The MemoryOverwriteRequestControl
>
> Start of informative comment:
>
> [...] The OS loader should not create the variable. Rather, the firmware
> is required to create it and must support the semantics described here.
>
> End of informative comment.
However, some OS kernels create the MOR variable even if the platform
firmware does not support it (see one Bugzilla reference below). This OS
issue breaks the logic added in the last patch.
Strengthen the MOR check by searching for the TCG or TCG2 protocols, as
edk2's implementation of MOR depends on (one of) those protocols.
The protocols are defined under MdePkg, thus there's no inter-package
dependency issue. In addition, calling UEFI services in
MorLockInitAtEndOfDxe() is safe, due to the following order of events /
actions:
- platform BDS signals the EndOfDxe event group,
- the SMM core installs the SmmEndOfDxe protocol,
- MorLockInitAtEndOfDxe() is invoked, and it calls UEFI services,
- some time later, platform BDS installs the DxeSmmReadyToLock protocol,
- SMM / SMRAM is locked down and UEFI services become unavailable to SMM
drivers.
Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Ladi Prosek <lprosek@redhat.com>
Cc: Star Zeng <star.zeng@intel.com>
Ref: https://bugzilla.redhat.com/show_bug.cgi?id=1498159
Suggested-by: Jiewen Yao <jiewen.yao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Tested-by: Ladi Prosek <lprosek@redhat.com>
If the platform supports SMM, a gRT->SetVariable() call at boot time
results in the following call tree to SecureBootHook():
RuntimeServiceSetVariable() [VariableSmmRuntimeDxe.c, unprivileged]
SmmVariableHandler() [VariableSmm.c, PRIVILEGED]
VariableServiceSetVariable() [Variable.c, PRIVILEGED]
SecureBootHook() [VariableSmm.c, PRIVILEGED]
//
// do nothing
//
SecureBootHook() [Measurement.c, unprivileged]
//
// measure variable if it
// is related to SB policy
//
And if the platform does not support SMM:
VariableServiceSetVariable() [Variable.c, unprivileged]
SecureBootHook() [Measurement.c, unprivileged]
//
// measure variable if it
// is related to SB policy
//
In other words, the measurement always happens outside of SMM.
Because there are two implementations of the SecureBootHook() API, one
that is called from SMM and does nothing, and another that is called
outside of SMM and measures variables, the function declaration should be
in a header file. This way the compiler can enforce that the function
declaration and all function definitions match.
"Variable.h" is used for "including common header files, defining internal
structures and functions used by Variable modules". Technically, we could
declare SecureBootHook() in "Variable.h". However, "Measurement.c" and
"VariableSmmRuntimeDxe.c" themselves do not include "Variable.h", and that
is likely intentional -- "Variable.h" exposes so much of the privileged
variable implementation that it is likely excluded from these C source
files on purpose.
Therefore introduce a new header file called "PrivilegePolymorphic.h".
"Variable.h" includes this header (so that all C source files that have
been allowed to see the variable internals learn about the new
SecureBootHook() declaration immediately). In "Measurement.c" and
"VariableSmmRuntimeDxe.c", include *only* the new header.
This change cleans up commit fa0737a839 ("MdeModulePkg Variable: Merge
from Auth Variable driver in SecurityPkg", 2015-07-01).
Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Ladi Prosek <lprosek@redhat.com>
Cc: Star Zeng <star.zeng@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Tested-by: Ladi Prosek <lprosek@redhat.com>
Instead of comparing a GUID with gZeroGuid via the CompareGuid API, the
commit uses the IsZeroGuid API to check if the given GUID is a zero GUID.
Cc: Feng Tian <feng.tian@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Feng Tian <feng.tian@Intel.com>
Since the variable check service has be separated to VarCheckLib
from Variable driver, so update Variable driver to consume the
separated VarCheckLib.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18286 6f19259b-4bc3-4df7-8a09-765794883524
MdeModulePkg has defined gZeroGuid in 'Guid/ZeroGuid.h', therefore, the
mZeroGuid defined in Universal/Variable/RuntimeDxe is redundant.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
Reviewed-by: Jaben Carsey <jaben.carsey@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@17840 6f19259b-4bc3-4df7-8a09-765794883524
What to do:
1. Merge from Auth Variable driver in SecurityPkg to Variable drive in
MdeModulePkg. Then the merged Variable driver in MdeModulePkg will
link to AuthVariableLib and TpmMeasurementLib.
AuthVariableLibNull and TpmMeasurementLibNull in MdeModulePkg
could be used for non auth variable support.
AuthVariableLib and DxeTpmMeasurementLib in SecurityPkg
may be used for auth variable support.
Why to do:
1. Remove code duplication and reduce maintenance effort.
After auth variable service separated from Auth Variable driver in SecurityPkg
to AuthVariableLib. The remaining code logic of Auth Variable driver in SecurityPkg
will be almost same with Variable driver in MdeModulePkg. Now it is to
merge them.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@17765 6f19259b-4bc3-4df7-8a09-765794883524
As the drivers and library do not reference gEfiSmmAccess2ProtocolGuid explicitly now
after SmmMemLib introduced.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16760 6f19259b-4bc3-4df7-8a09-765794883524
for trying to reclaim variable space at EndOfDxe.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16687 6f19259b-4bc3-4df7-8a09-765794883524
and follow UEFI spec to check UEFI defined variables.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16579 6f19259b-4bc3-4df7-8a09-765794883524
1. Usage information in INF file comment blocks are either incomplete or incorrect.
This includes usage information for Protocols/PPIs/GUIDs/PCDs/HOBs/Events/BootModes.
The syntax for usage information in comment blocks is defined in the EDK II Module Information (INF) Specification
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Zeng, Star <star.zeng@intel.com>
Reviewed-by: Gao, Liming <liming.gao@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@15962 6f19259b-4bc3-4df7-8a09-765794883524
PEI variable implementation checks only the variable header signature for validity. This does not seem robust if system crash occurred during previous Reclaim() operation. If the crash occurred while FTW was rewriting the variable FV, the signature could be valid even though the rest of the FV isn't valid.
Solution: Add a FaultTolerantWritePei driver to check and provide the FTW last write status, then PEI variable and early phase(before FTW protocol ready) of DXE variable can check the status and determine if all or partial variable data has been backed up in spare block, and then use the backed up data.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@14454 6f19259b-4bc3-4df7-8a09-765794883524
Add code in BdsDxe driver to call the protocol to mark the read-only variables defined in the UEFI Spec.
Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Guo Dong <guo.dong@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@14372 6f19259b-4bc3-4df7-8a09-765794883524