1 files changed, 83 insertions, 3 deletions
diff --git a/MdeModulePkg/Universal/SectionExtractionDxe/SectionExtractionDxe.c b/MdeModulePkg/Universal/SectionExtractionDxe/SectionExtractionDxe.c
index 0cdfdefeb8..b100883be6 100644
--- a/MdeModulePkg/Universal/SectionExtractionDxe/SectionExtractionDxe.c
+++ b/MdeModulePkg/Universal/SectionExtractionDxe/SectionExtractionDxe.c
@@ -20,9 +20,89 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
 #include <Library/BaseMemoryLib.h>
 #include <Library/UefiBootServicesTableLib.h>
 
-//
-// Function prototype for Section Extraction Protocol service
-//
+/**
+  The ExtractSection() function processes the input section and
+  allocates a buffer from the pool in which it returns the section
+  contents. If the section being extracted contains
+  authentication information (the section's
+  GuidedSectionHeader.Attributes field has the
+  EFI_GUIDED_SECTION_AUTH_STATUS_VALID bit set), the values
+  returned in AuthenticationStatus must reflect the results of
+  the authentication operation. Depending on the algorithm and
+  size of the encapsulated data, the time that is required to do
+  a full authentication may be prohibitively long for some
+  classes of systems. To indicate this, use
+  EFI_SECURITY_POLICY_PROTOCOL_GUID, which may be published by
+  the security policy driver (see the Platform Initialization
+  Driver Execution Environment Core Interface Specification for
+  more details and the GUID definition). If the
+  EFI_SECURITY_POLICY_PROTOCOL_GUID exists in the handle
+  database, then, if possible, full authentication should be
+  skipped and the section contents simply returned in the
+  OutputBuffer. In this case, the
+  EFI_AUTH_STATUS_PLATFORM_OVERRIDE bit AuthenticationStatus
+  must be set on return. ExtractSection() is callable only from
+  TPL_NOTIFY and below. Behavior of ExtractSection() at any
+  EFI_TPL above TPL_NOTIFY is undefined. Type EFI_TPL is
+  defined in RaiseTPL() in the UEFI 2.0 specification.
+
+
+  @param This         Indicates the
+                      EFI_GUIDED_SECTION_EXTRACTION_PROTOCOL instance.
+  @param InputSection Buffer containing the input GUIDed section
+                      to be processed. OutputBuffer OutputBuffer
+                      is allocated from boot services pool
+                      memory and contains the new section
+                      stream. The caller is responsible for
+                      freeing this buffer.
+  @param OutputBuffer *OutputBuffer is allocated from boot services
+                      pool memory and contains the new section stream.
+                      The caller is responsible for freeing this buffer.
+  @param OutputSize   A pointer to a caller-allocated UINTN in
+                      which the size of OutputBuffer allocation
+                      is stored. If the function returns
+                      anything other than EFI_SUCCESS, the value
+                      of OutputSize is undefined.
+
+  @param AuthenticationStatus A pointer to a caller-allocated
+                              UINT32 that indicates the
+                              authentication status of the
+                              output buffer. If the input
+                              section's
+                              GuidedSectionHeader.Attributes
+                              field has the
+                              EFI_GUIDED_SECTION_AUTH_STATUS_VAL
+                              bit as clear, AuthenticationStatus
+                              must return zero. Both local bits
+                              (19:16) and aggregate bits (3:0)
+                              in AuthenticationStatus are
+                              returned by ExtractSection().
+                              These bits reflect the status of
+                              the extraction operation. The bit
+                              pattern in both regions must be
+                              the same, as the local and
+                              aggregate authentication statuses
+                              have equivalent meaning at this
+                              level. If the function returns
+                              anything other than EFI_SUCCESS,
+                              the value of AuthenticationStatus
+                              is undefined.
+
+
+  @retval EFI_SUCCESS          The InputSection was successfully
+                               processed and the section contents were
+                               returned.
+
+  @retval EFI_OUT_OF_RESOURCES The system has insufficient
+                               resources to process the
+                               request.
+
+  @retval EFI_INVALID_PARAMETER The GUID in InputSection does
+                                not match this instance of the
+                                GUIDed Section Extraction
+                                Protocol.
+
+**/
 EFI_STATUS
 EFIAPI
 CustomGuidedSectionExtract (