OvmfPkg/Tcg2ConfigPei: factor out InternalTpm12Detect()

Move the calls to the Tpm12RequestUseTpm() and Tpm12SubmitCommand()
Tpm12DeviceLib functions to a separate C file, so that we can override
these actions in a subsequent patch.

This code movement requires moving the TPM_RSP_GET_TICKS / TestTpm12()
helper structure / function too.

While at it, give the TestTpm12() function @retval / @return
documentation, plus wrap an overlong line in it.

Functionally, this patch is a no-op.

Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
Cc: Eric Auger <eric.auger@redhat.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Marc-André Lureau <marcandre.lureau@redhat.com>
Cc: Philippe Mathieu-Daudé <philmd@redhat.com>
Cc: Simon Hardy <simon.hardy@itdev.co.uk>
Cc: Stefan Berger <stefanb@linux.ibm.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=2728
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Message-Id: <20200520225841.17793-3-lersek@redhat.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@arm.com>
Tested-by: Ard Biesheuvel <ard.biesheuvel@arm.com>

4 files changed, 115 insertions, 42 deletions

diff --git a/OvmfPkg/Tcg/Tcg2Config/Tcg2ConfigPei.inf b/OvmfPkg/Tcg/Tcg2Config/Tcg2ConfigPei.inf
index b79d0a3fb9..aa996b7da7 100644
--- a/OvmfPkg/Tcg/Tcg2Config/Tcg2ConfigPei.inf
+++ b/OvmfPkg/Tcg/Tcg2Config/Tcg2ConfigPei.inf
@@ -21,6 +21,8 @@
 

 [Sources]

   Tcg2ConfigPeim.c

+  Tpm12Support.c

+  Tpm12Support.h

 

 [Packages]

   MdePkg/MdePkg.dec

diff --git a/OvmfPkg/Tcg/Tcg2Config/Tcg2ConfigPeim.c b/OvmfPkg/Tcg/Tcg2Config/Tcg2ConfigPeim.c
index 44abd6c541..cc54d95cad 100644
--- a/OvmfPkg/Tcg/Tcg2Config/Tcg2ConfigPeim.c
+++ b/OvmfPkg/Tcg/Tcg2Config/Tcg2ConfigPeim.c
@@ -15,13 +15,13 @@
 #include <PiPei.h>

 

 #include <Guid/TpmInstance.h>

-#include <Library/BaseLib.h>

 #include <Library/DebugLib.h>

 #include <Library/PeiServicesLib.h>

 #include <Library/Tpm2DeviceLib.h>

-#include <Library/Tpm12DeviceLib.h>

 #include <Ppi/TpmInitialized.h>

 

+#include "Tpm12Support.h"

+

 STATIC CONST EFI_PEI_PPI_DESCRIPTOR mTpmSelectedPpi = {

   (EFI_PEI_PPI_DESCRIPTOR_PPI | EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST),

   &gEfiTpmDeviceSelectedGuid,

@@ -34,44 +34,6 @@ STATIC CONST EFI_PEI_PPI_DESCRIPTOR  mTpmInitializationDonePpiList = {
   NULL

 };

 

-#pragma pack (1)

-

-typedef struct {

-  TPM_RSP_COMMAND_HDR   Hdr;

-  TPM_CURRENT_TICKS     CurrentTicks;

-} TPM_RSP_GET_TICKS;

-

-#pragma pack ()

-

-/**

-  Probe for the TPM for 1.2 version, by sending TPM1.2 GetTicks

-

-  Sending a TPM1.2 command to a TPM2 should return a TPM1.2

-  header (tag = 0xc4) and error code (TPM_BADTAG = 0x1e)

-**/

-static

-EFI_STATUS

-TestTpm12 (

-  )

-{

-  EFI_STATUS           Status;

-  TPM_RQU_COMMAND_HDR  Command;

-  TPM_RSP_GET_TICKS    Response;

-  UINT32               Length;

-

-  Command.tag       = SwapBytes16 (TPM_TAG_RQU_COMMAND);

-  Command.paramSize = SwapBytes32 (sizeof (Command));

-  Command.ordinal   = SwapBytes32 (TPM_ORD_GetTicks);

-

-  Length = sizeof (Response);

-  Status = Tpm12SubmitCommand (sizeof (Command), (UINT8 *)&Command, &Length, (UINT8 *)&Response);

-  if (EFI_ERROR (Status)) {

-    return Status;

-  }

-

-  return EFI_SUCCESS;

-}

-

 /**

   The entry point for Tcg2 configuration driver.

 

@@ -90,8 +52,8 @@ Tcg2ConfigPeimEntryPoint (
 

   DEBUG ((DEBUG_INFO, "%a\n", __FUNCTION__));

 

-  Status = Tpm12RequestUseTpm ();

-  if (!EFI_ERROR (Status) && !EFI_ERROR (TestTpm12 ())) {

+  Status = InternalTpm12Detect ();

+  if (!EFI_ERROR (Status)) {

     DEBUG ((DEBUG_INFO, "%a: TPM1.2 detected\n", __FUNCTION__));

     Size = sizeof (gEfiTpmDeviceInstanceTpm12Guid);

     Status = PcdSetPtrS (

diff --git a/OvmfPkg/Tcg/Tcg2Config/Tpm12Support.c b/OvmfPkg/Tcg/Tcg2Config/Tpm12Support.c
new file mode 100644
index 0000000000..4f5a775c7a
--- /dev/null
+++ b/OvmfPkg/Tcg/Tcg2Config/Tpm12Support.c
@@ -0,0 +1,79 @@
+/** @file

+  Implement the InternalTpm12Detect() function on top of the Tpm12DeviceLib

+  class.

+

+  Copyright (C) 2020, Red Hat, Inc.

+

+  SPDX-License-Identifier: BSD-2-Clause-Patent

+**/

+

+#include <Library/BaseLib.h>

+#include <Library/Tpm12DeviceLib.h>

+

+#include "Tpm12Support.h"

+

+#pragma pack (1)

+typedef struct {

+  TPM_RSP_COMMAND_HDR   Hdr;

+  TPM_CURRENT_TICKS     CurrentTicks;

+} TPM_RSP_GET_TICKS;

+#pragma pack ()

+

+/**

+  Probe for the TPM for 1.2 version, by sending TPM1.2 GetTicks

+

+  Sending a TPM1.2 command to a TPM2 should return a TPM1.2

+  header (tag = 0xc4) and error code (TPM_BADTAG = 0x1e)

+

+  @retval EFI_SUCCESS  TPM version 1.2 probing successful.

+

+  @return              Error codes propagated from Tpm12SubmitCommand().

+**/

+STATIC

+EFI_STATUS

+TestTpm12 (

+  )

+{

+  EFI_STATUS           Status;

+  TPM_RQU_COMMAND_HDR  Command;

+  TPM_RSP_GET_TICKS    Response;

+  UINT32               Length;

+

+  Command.tag       = SwapBytes16 (TPM_TAG_RQU_COMMAND);

+  Command.paramSize = SwapBytes32 (sizeof (Command));

+  Command.ordinal   = SwapBytes32 (TPM_ORD_GetTicks);

+

+  Length = sizeof (Response);

+  Status = Tpm12SubmitCommand (sizeof (Command), (UINT8 *)&Command, &Length,

+             (UINT8 *)&Response);

+  if (EFI_ERROR (Status)) {

+    return Status;

+  }

+

+  return EFI_SUCCESS;

+}

+

+/**

+  Detect the presence of a TPM with interface version 1.2.

+

+  @retval EFI_SUCCESS      TPM-1.2 available. The Tpm12RequestUseTpm() and

+                           Tpm12SubmitCommand(TPM_ORD_GetTicks) operations

+                           (from the Tpm12DeviceLib class) have succeeded.

+

+  @return                  Error codes propagated from Tpm12RequestUseTpm() and

+                           Tpm12SubmitCommand().

+**/

+EFI_STATUS

+InternalTpm12Detect (

+  VOID

+  )

+{

+  EFI_STATUS Status;

+

+  Status = Tpm12RequestUseTpm ();

+  if (EFI_ERROR (Status)) {

+    return Status;

+  }

+

+  return TestTpm12 ();

+}

diff --git a/OvmfPkg/Tcg/Tcg2Config/Tpm12Support.h b/OvmfPkg/Tcg/Tcg2Config/Tpm12Support.h
new file mode 100644
index 0000000000..c739775d23
--- /dev/null
+++ b/OvmfPkg/Tcg/Tcg2Config/Tpm12Support.h
@@ -0,0 +1,30 @@
+/** @file

+  Declare the InternalTpm12Detect() function, hiding the TPM-1.2 detection

+  internals.

+

+  Copyright (C) 2020, Red Hat, Inc.

+

+  SPDX-License-Identifier: BSD-2-Clause-Patent

+**/

+

+#ifndef TPM12_SUPPORT_H_

+#define TPM12_SUPPORT_H_

+

+#include <Uefi/UefiBaseType.h>

+

+/**

+  Detect the presence of a TPM with interface version 1.2.

+

+  @retval EFI_SUCCESS      TPM-1.2 available. The Tpm12RequestUseTpm() and

+                           Tpm12SubmitCommand(TPM_ORD_GetTicks) operations

+                           (from the Tpm12DeviceLib class) have succeeded.

+

+  @return                  Error codes propagated from Tpm12RequestUseTpm() and

+                           Tpm12SubmitCommand().

+**/

+EFI_STATUS

+InternalTpm12Detect (

+  VOID

+  );

+

+#endif // TPM12_SUPPORT_H_