[PATCH v7 11/11] SecurityPkg: Add option to reset secure boot keys.


Grzegorz Bernacki
 

This commit add option which allows reset content of Secure Boot
keys and databases to default variables.

Signed-off-by: Grzegorz Bernacki <gjb@semihalf.com>
Reviewed-by: Sunny Wang <sunny.wang@arm.com>
Reviewed-by: Jiewen Yao <Jiewen.yao@intel.com>
Reviewed-by: Pete Batard <pete@akeo.ie>
Tested-by: Pete Batard <pete@akeo.ie> on Raspberry Pi 4
---
SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigDxe.inf | 1 +
SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigNvData.h | 2 +
SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfig.vfr | 6 +
SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigImpl.c | 154 ++++++++++++++++++++
SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigStrings.uni | 4 +
5 files changed, 167 insertions(+)

diff --git a/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigDxe.inf b/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigDxe.inf
index 14c7311b08..420687a211 100644
--- a/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigDxe.inf
+++ b/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigDxe.inf
@@ -110,6 +110,7 @@
[Protocols]
gEfiHiiConfigAccessProtocolGuid ## PRODUCES
gEfiDevicePathProtocolGuid ## PRODUCES
+ gEfiHiiPopupProtocolGuid

[Depex]
gEfiHiiConfigRoutingProtocolGuid AND
diff --git a/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigNvData.h b/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigNvData.h
index 6e54a4b0f2..4ecc25efc3 100644
--- a/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigNvData.h
+++ b/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigNvData.h
@@ -54,6 +54,8 @@ SPDX-License-Identifier: BSD-2-Clause-Patent

#define KEY_VALUE_FROM_DBX_TO_LIST_FORM 0x100f

+#define KEY_SECURE_BOOT_RESET_TO_DEFAULT 0x1010
+
#define KEY_SECURE_BOOT_OPTION 0x1100
#define KEY_SECURE_BOOT_PK_OPTION 0x1101
#define KEY_SECURE_BOOT_KEK_OPTION 0x1102
diff --git a/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfig.vfr b/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfig.vfr
index fa7e11848c..e4560c592c 100644
--- a/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfig.vfr
+++ b/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfig.vfr
@@ -69,6 +69,12 @@ formset
endif;
endif;

+ text
+ help = STRING_TOKEN(STR_SECURE_RESET_TO_DEFAULTS_HELP),
+ text = STRING_TOKEN(STR_SECURE_RESET_TO_DEFAULTS),
+ flags = INTERACTIVE,
+ key = KEY_SECURE_BOOT_RESET_TO_DEFAULT;
+
endform;

//
diff --git a/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigImpl.c b/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigImpl.c
index f527aa32e6..f102607a27 100644
--- a/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigImpl.c
+++ b/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigImpl.c
@@ -8,6 +8,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
**/

#include "SecureBootConfigImpl.h"
+#include <Protocol/HiiPopup.h>
#include <Library/BaseCryptLib.h>
#include <Library/SecureBootVariableLib.h>
#include <Library/SecureBootVariableProvisionLib.h>
@@ -4155,6 +4156,132 @@ ON_EXIT:
return Status;
}

+/**
+ This function reinitializes Secure Boot variables with default values.
+
+ @retval EFI_SUCCESS Success to update the signature list page
+ @retval others Fail to delete or enroll signature data.
+**/
+
+STATIC EFI_STATUS
+EFIAPI
+KeyEnrollReset (
+ VOID
+ )
+{
+ EFI_STATUS Status;
+ UINT8 SetupMode;
+
+ Status = EFI_SUCCESS;
+
+ Status = SetSecureBootMode (CUSTOM_SECURE_BOOT_MODE);
+ if (EFI_ERROR(Status)) {
+ return Status;
+ }
+
+ // Clear all the keys and databases
+ Status = DeleteDb ();
+ if (EFI_ERROR (Status) && (Status != EFI_NOT_FOUND)) {
+ DEBUG ((DEBUG_ERROR, "Fail to clear DB: %r\n", Status));
+ return Status;
+ }
+
+ Status = DeleteDbx ();
+ if (EFI_ERROR (Status) && (Status != EFI_NOT_FOUND)) {
+ DEBUG ((DEBUG_ERROR, "Fail to clear DBX: %r\n", Status));
+ return Status;
+ }
+
+ Status = DeleteDbt ();
+ if (EFI_ERROR (Status) && (Status != EFI_NOT_FOUND)) {
+ DEBUG ((DEBUG_ERROR, "Fail to clear DBT: %r\n", Status));
+ return Status;
+ }
+
+ Status = DeleteKEK ();
+ if (EFI_ERROR (Status) && (Status != EFI_NOT_FOUND)) {
+ DEBUG ((DEBUG_ERROR, "Fail to clear KEK: %r\n", Status));
+ return Status;
+ }
+
+ Status = DeletePlatformKey ();
+ if (EFI_ERROR (Status) && (Status != EFI_NOT_FOUND)) {
+ DEBUG ((DEBUG_ERROR, "Fail to clear PK: %r\n", Status));
+ return Status;
+ }
+
+ // After PK clear, Setup Mode shall be enabled
+ Status = GetSetupMode (&SetupMode);
+ if (EFI_ERROR (Status)) {
+ DEBUG ((DEBUG_ERROR, "Cannot get SetupMode variable: %r\n",
+ Status));
+ return Status;
+ }
+
+ if (SetupMode == USER_MODE) {
+ DEBUG((DEBUG_INFO, "Skipped - USER_MODE\n"));
+ return EFI_SUCCESS;
+ }
+
+ Status = SetSecureBootMode (CUSTOM_SECURE_BOOT_MODE);
+ if (EFI_ERROR (Status)) {
+ DEBUG ((DEBUG_ERROR, "Cannot set CUSTOM_SECURE_BOOT_MODE: %r\n",
+ Status));
+ return EFI_SUCCESS;
+ }
+
+ // Enroll all the keys from default variables
+ Status = EnrollDbFromDefault ();
+ if (EFI_ERROR (Status)) {
+ DEBUG ((DEBUG_ERROR, "Cannot enroll db: %r\n", Status));
+ goto error;
+ }
+
+ Status = EnrollDbxFromDefault ();
+ if (EFI_ERROR (Status)) {
+ DEBUG ((DEBUG_ERROR, "Cannot enroll dbx: %r\n", Status));
+ }
+
+ Status = EnrollDbtFromDefault ();
+ if (EFI_ERROR (Status)) {
+ DEBUG ((DEBUG_ERROR, "Cannot enroll dbt: %r\n", Status));
+ }
+
+ Status = EnrollKEKFromDefault ();
+ if (EFI_ERROR (Status)) {
+ DEBUG ((DEBUG_ERROR, "Cannot enroll KEK: %r\n", Status));
+ goto cleardbs;
+ }
+
+ Status = EnrollPKFromDefault ();
+ if (EFI_ERROR (Status)) {
+ DEBUG ((DEBUG_ERROR, "Cannot enroll PK: %r\n", Status));
+ goto clearKEK;
+ }
+
+ Status = SetSecureBootMode (STANDARD_SECURE_BOOT_MODE);
+ if (EFI_ERROR (Status)) {
+ DEBUG ((DEBUG_ERROR, "Cannot set CustomMode to STANDARD_SECURE_BOOT_MODE\n"
+ "Please do it manually, otherwise system can be easily compromised\n"));
+ }
+
+ return Status;
+
+clearKEK:
+ DeleteKEK ();
+
+cleardbs:
+ DeleteDbt ();
+ DeleteDbx ();
+ DeleteDb ();
+
+error:
+ if (SetSecureBootMode (STANDARD_SECURE_BOOT_MODE) != EFI_SUCCESS) {
+ DEBUG ((DEBUG_ERROR, "Cannot set mode to Secure: %r\n", Status));
+ }
+ return Status;
+}
+
/**
This function is called to provide results data to the driver.

@@ -4206,6 +4333,8 @@ SecureBootCallback (
SECUREBOOT_CONFIG_PRIVATE_DATA *PrivateData;
BOOLEAN GetBrowserDataResult;
ENROLL_KEY_ERROR EnrollKeyErrorCode;
+ EFI_HII_POPUP_PROTOCOL *HiiPopup;
+ EFI_HII_POPUP_SELECTION UserSelection;

Status = EFI_SUCCESS;
SecureBootEnable = NULL;
@@ -4756,6 +4885,31 @@ SecureBootCallback (
FreePool (SetupMode);
}
break;
+ case KEY_SECURE_BOOT_RESET_TO_DEFAULT:
+ {
+ Status = gBS->LocateProtocol (&gEfiHiiPopupProtocolGuid, NULL, (VOID **) &HiiPopup);
+ if (EFI_ERROR (Status)) {
+ return Status;
+ }
+ Status = HiiPopup->CreatePopup (
+ HiiPopup,
+ EfiHiiPopupStyleInfo,
+ EfiHiiPopupTypeYesNo,
+ Private->HiiHandle,
+ STRING_TOKEN (STR_RESET_TO_DEFAULTS_POPUP),
+ &UserSelection
+ );
+ if (UserSelection == EfiHiiPopupSelectionYes) {
+ Status = KeyEnrollReset ();
+ }
+ //
+ // Update secure boot strings after key reset
+ //
+ if (Status == EFI_SUCCESS) {
+ Status = UpdateSecureBootString (Private);
+ SecureBootExtractConfigFromVariable (Private, IfrNvData);
+ }
+ }
default:
break;
}
diff --git a/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigStrings.uni b/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigStrings.uni
index ac783453cc..0d01701de7 100644
--- a/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigStrings.uni
+++ b/SecurityPkg/VariableAuthenticated/SecureBootConfigDxe/SecureBootConfigStrings.uni
@@ -21,6 +21,10 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
#string STR_SECURE_BOOT_PROMPT #language en-US "Attempt Secure Boot"
#string STR_SECURE_BOOT_HELP #language en-US "Enable/Disable the Secure Boot feature after platform reset"

+#string STR_SECURE_RESET_TO_DEFAULTS_HELP #language en-US "Enroll keys with data from default variables"
+#string STR_SECURE_RESET_TO_DEFAULTS #language en-US "Reset Secure Boot Keys"
+#string STR_RESET_TO_DEFAULTS_POPUP #language en-US "Secure Boot Keys & databases will be initialized from defaults.\n Are you sure?"
+
#string STR_SECURE_BOOT_ENROLL_SIGNATURE #language en-US "Enroll Signature"
#string STR_SECURE_BOOT_DELETE_SIGNATURE #language en-US "Delete Signature"
#string STR_SECURE_BOOT_DELETE_LIST_FORM #language en-US "Delete Signature List Form"
--
2.25.1

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