[PATCH v1 1/4] SecurityPkg: limit verification of enrolled PK in setup mode

["Jan Bobek" <jbobek@nvidia.com>]

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=2506

Per UEFI spec, enrolling a new PK in setup mode should not require a
self-signature. Introduce a feature PCD called PcdRequireSelfSignedPk
to control this requirement. Default to TRUE in order to preserve the
legacy behavior.

Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Min Xu <min.m.xu@intel.com>
Co-authored-by: Matthew Carlson <macarl@microsoft.com>
Signed-off-by: Jan Bobek <jbobek@nvidia.com>
---
 SecurityPkg/SecurityPkg.dec                             | 7 +++++++
 SecurityPkg/Library/AuthVariableLib/AuthVariableLib.inf | 3 +++
 SecurityPkg/Library/AuthVariableLib/AuthService.c       | 9 +++++++--
 3 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/SecurityPkg/SecurityPkg.dec b/SecurityPkg/SecurityPkg.dec
index 8257f11d17c7..d3b7ad7ff6fb 100644
--- a/SecurityPkg/SecurityPkg.dec
+++ b/SecurityPkg/SecurityPkg.dec
@@ -580,5 +580,12 @@ [PcdsDynamic, PcdsDynamicEx]
   ## This PCD records LASA field in CC EVENTLOG ACPI table.
   gEfiSecurityPkgTokenSpaceGuid.PcdCcEventlogAcpiTableLasa|0|UINT64|0x00010026
 
+[PcdsFeatureFlag]
+  ## Indicates if the platform requires PK to be self-signed when setting the PK in setup mode.
+  #   TRUE  - Require PK to be self-signed.
+  #   FALSE - Do not require PK to be self-signed.
+  # @Prompt Require PK to be self-signed
+  gEfiMdeModulePkgTokenSpaceGuid.PcdRequireSelfSignedPk|TRUE|BOOLEAN|0x00010027
+
 [UserExtensions.TianoCore."ExtraFiles"]
   SecurityPkgExtra.uni
diff --git a/SecurityPkg/Library/AuthVariableLib/AuthVariableLib.inf b/SecurityPkg/Library/AuthVariableLib/AuthVariableLib.inf
index 8eadeebcebd7..e5985c5f8b60 100644
--- a/SecurityPkg/Library/AuthVariableLib/AuthVariableLib.inf
+++ b/SecurityPkg/Library/AuthVariableLib/AuthVariableLib.inf
@@ -86,3 +86,6 @@ [Guids]
   gEfiCertTypeRsa2048Sha256Guid  ## SOMETIMES_CONSUMES   ## GUID  # Unique ID for the type of the certificate.
   gEfiCertPkcs7Guid              ## SOMETIMES_CONSUMES   ## GUID  # Unique ID for the type of the certificate.
   gEfiCertX509Guid               ## SOMETIMES_CONSUMES   ## GUID  # Unique ID for the type of the signature.
+
+[FeaturePcd]
+  gEfiMdeModulePkgTokenSpaceGuid.PcdRequireSelfSignedPk
diff --git a/SecurityPkg/Library/AuthVariableLib/AuthService.c b/SecurityPkg/Library/AuthVariableLib/AuthService.c
index 054ee4d1d988..e9989695626e 100644
--- a/SecurityPkg/Library/AuthVariableLib/AuthService.c
+++ b/SecurityPkg/Library/AuthVariableLib/AuthService.c
@@ -603,7 +603,10 @@ ProcessVarWithPk (
   // Init state of Del. State may change due to secure check
   //
   Del = FALSE;
-  if ((InCustomMode () && UserPhysicalPresent ()) || ((mPlatformMode == SETUP_MODE) && !IsPk)) {
+  if (  (InCustomMode () && UserPhysicalPresent ())
+     || (  (mPlatformMode == SETUP_MODE)
+        && !(FeaturePcdGet (PcdRequireSelfSignedPk) && IsPk)))
+  {
     Payload     = (UINT8 *)Data + AUTHINFO2_SIZE (Data);
     PayloadSize = DataSize - AUTHINFO2_SIZE (Data);
     if (PayloadSize == 0) {
@@ -627,7 +630,9 @@ ProcessVarWithPk (
       return Status;
     }
 
-    if ((mPlatformMode != SETUP_MODE) || IsPk) {
+    if (  (mPlatformMode != SETUP_MODE)
+       || (FeaturePcdGet (PcdRequireSelfSignedPk) && IsPk))
+    {
       Status = VendorKeyIsModified ();
     }
   } else if (mPlatformMode == USER_MODE) {
-- 
2.30.2