MdeModulePkg/Library/DxeCrc32GuidedSectionExtractLib/DxeCrc32GuidedSectionExtractLib.c

   1 /** @file
   2
   3   Implements CRC32 guided section handler to parse CRC32 encapsulation section,
   4   extract data and authenticate 32 bit CRC value.
   5
   6 Copyright (c) 2007 - 2008, Intel Corporation
   7 All rights reserved. This program and the accompanying materials
   8 are licensed and made available under the terms and conditions of the BSD License
   9 which accompanies this distribution.  The full text of the license may be found at
  10 http://opensource.org/licenses/bsd-license.php
  11
  12 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  13 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  14
  15 **/
  16
  17 #include <PiDxe.h>
  18 #include <Protocol/Crc32GuidedSectionExtraction.h>
  19 #include <Protocol/SecurityPolicy.h>
  20 #include <Library/ExtractGuidedSectionLib.h>
  21 #include <Library/DebugLib.h>
  22 #include <Library/BaseMemoryLib.h>
  23 #include <Library/UefiBootServicesTableLib.h>
  24
  25 typedef struct {
  26   EFI_GUID_DEFINED_SECTION  GuidedSectionHeader;
  27   UINT32                    CRC32Checksum;
  28 } CRC32_SECTION_HEADER;
  29
  30 /**
  31
  32   The implementation of Crc32 guided section GetInfo() to get
  33   size and attribute of the guided section.
  34
  35   @param InputSection       Buffer containing the input GUIDed section to be processed.
  36   @param OutputBufferSize   The size of OutputBuffer.
  37   @param ScratchBufferSize  The size of ScratchBuffer.
  38   @param SectionAttribute   The attribute of the input guided section.
  39
  40   @retval EFI_SUCCESS            The size of destination buffer, the size of scratch buffer and
  41                                  the attribute of the input section are successull retrieved.
  42   @retval EFI_INVALID_PARAMETER  The GUID in InputSection does not match this instance guid.
  43
  44 **/
  45 EFI_STATUS
  46 EFIAPI
  47 Crc32GuidedSectionGetInfo (
  48   IN  CONST VOID  *InputSection,
  49   OUT UINT32      *OutputBufferSize,
  50   OUT UINT32      *ScratchBufferSize,
  51   OUT UINT16      *SectionAttribute
  52   )
  53 {
  54   //
  55   // Check whether the input guid section is recognized.
  56   //
  57   if (!CompareGuid (
  58         &gEfiCrc32GuidedSectionExtractionProtocolGuid,
  59         &(((EFI_GUID_DEFINED_SECTION *) InputSection)->SectionDefinitionGuid))) {
  60     return EFI_INVALID_PARAMETER;
  61   }
  62   //
  63   // Retrieve the size and attribute of the input section data.
  64   //
  65   *SectionAttribute  = ((EFI_GUID_DEFINED_SECTION *) InputSection)->Attributes;
  66   *ScratchBufferSize = 0;
  67   *OutputBufferSize  = *(UINT32 *) (((EFI_COMMON_SECTION_HEADER *) InputSection)->Size) & 0x00ffffff;
  68   *OutputBufferSize  -= ((EFI_GUID_DEFINED_SECTION *) InputSection)->DataOffset;
  69
  70   return EFI_SUCCESS;
  71 }
  72
  73 /**
  74
  75   The implementation of Crc32 Guided section extraction to get the section data.
  76
  77   @param InputSection    Buffer containing the input GUIDed section to be processed.
  78   @param OutputBuffer    to contain the output data, which is allocated by the caller.
  79   @param ScratchBuffer   A pointer to a caller-allocated buffer for function internal use.
  80   @param AuthenticationStatus A pointer to a caller-allocated UINT32 that indicates the
  81                          authentication status of the output buffer.
  82
  83   @retval EFI_SUCCESS            Section Data and Auth Status is extracted successfully.
  84   @retval EFI_INVALID_PARAMETER  The GUID in InputSection does not match this instance guid.
  85
  86 **/
  87 EFI_STATUS
  88 EFIAPI
  89 Crc32GuidedSectionHandler (
  90   IN CONST  VOID    *InputSection,
  91   OUT       VOID    **OutputBuffer,
  92   IN        VOID    *ScratchBuffer,        OPTIONAL
  93   OUT       UINT32  *AuthenticationStatus
  94   )
  95 {
  96   EFI_STATUS                Status;
  97   CRC32_SECTION_HEADER      *Crc32SectionHeader;
  98   UINT32                    Crc32Checksum;
  99   UINT32                    OutputBufferSize;
 100   VOID                      *DummyInterface;
 101
 102   //
 103   // Check whether the input guid section is recognized.
 104   //
 105   if (!CompareGuid (
 106         &gEfiCrc32GuidedSectionExtractionProtocolGuid,
 107         &(((EFI_GUID_DEFINED_SECTION *) InputSection)->SectionDefinitionGuid))) {
 108     return EFI_INVALID_PARAMETER;
 109   }
 110
 111   //
 112   // Init Checksum value to Zero.
 113   //
 114   Crc32Checksum = 0;
 115   //
 116   // Points to the Crc32 section header
 117   //
 118   Crc32SectionHeader = (CRC32_SECTION_HEADER *) InputSection;
 119   *OutputBuffer      = (UINT8 *) InputSection + Crc32SectionHeader->GuidedSectionHeader.DataOffset;
 120   OutputBufferSize   = *(UINT32 *) (((EFI_COMMON_SECTION_HEADER *) InputSection)->Size) & 0x00ffffff;
 121   OutputBufferSize   -= Crc32SectionHeader->GuidedSectionHeader.DataOffset;
 122
 123   //
 124   // Implictly CRC32 GUIDed section should have STATUS_VALID bit set
 125   //
 126   ASSERT (Crc32SectionHeader->GuidedSectionHeader.Attributes & EFI_GUIDED_SECTION_AUTH_STATUS_VALID);
 127   *AuthenticationStatus = EFI_AUTH_STATUS_IMAGE_SIGNED;
 128
 129   //
 130   // Check whether there exists EFI_SECURITY_POLICY_PROTOCOL_GUID.
 131   //
 132   Status = gBS->LocateProtocol (&gEfiSecurityPolicyProtocolGuid, NULL, &DummyInterface);
 133   if (!EFI_ERROR (Status)) {
 134     //
 135     // If SecurityPolicy Protocol exist, AUTH platform override bit is set.
 136     //
 137     *AuthenticationStatus |= EFI_AUTH_STATUS_PLATFORM_OVERRIDE;
 138   } else {
 139     //
 140     // Calculate CRC32 Checksum of Image
 141     //
 142     Status = gBS->CalculateCrc32 (*OutputBuffer, OutputBufferSize, &Crc32Checksum);
 143     if (Status == EFI_SUCCESS) {
 144       if (Crc32Checksum != Crc32SectionHeader->CRC32Checksum) {
 145         //
 146         // If Crc32 checksum is not matched, AUTH tested failed bit is set.
 147         //
 148         *AuthenticationStatus |= EFI_AUTH_STATUS_TEST_FAILED;
 149       }
 150     } else {
 151       //
 152       // If Crc32 checksum is not calculated, AUTH not tested bit is set.
 153       //
 154       *AuthenticationStatus |= EFI_AUTH_STATUS_NOT_TESTED;
 155     }
 156   }
 157
 158   return EFI_SUCCESS;
 159 }
 160
 161 /**
 162   Register Crc32 section handler.
 163
 164   @retval  RETURN_SUCCESS            Register successfully.
 165   @retval  RETURN_OUT_OF_RESOURCES   No enough memory to register this handler.
 166 **/
 167 EFI_STATUS
 168 EFIAPI
 169 DxeCrc32GuidedSectionExtractLibConstructor (
 170   )
 171 {
 172   return ExtractGuidedSectionRegisterHandlers (
 173           &gEfiCrc32GuidedSectionExtractionProtocolGuid,
 174           Crc32GuidedSectionGetInfo,
 175           Crc32GuidedSectionHandler
 176           );
 177 }
 178