1 /** @file 2 3 This library registers CRC32 guided section handler 4 to parse CRC32 encapsulation section and extract raw data. 5 It uses UEFI boot service CalculateCrc32 to authenticate 32 bit CRC value. 6 7 Copyright (c) 2007 - 2011, Intel Corporation. All rights reserved.<BR> 8 This program and the accompanying materials 9 are licensed and made available under the terms and conditions of the BSD License 10 which accompanies this distribution. The full text of the license may be found at 11 http://opensource.org/licenses/bsd-license.php 12 13 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, 14 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. 15 16 **/ 17 18 #include <PiDxe.h> 19 #include <Guid/Crc32GuidedSectionExtraction.h> 20 #include <Protocol/SecurityPolicy.h> 21 #include <Library/ExtractGuidedSectionLib.h> 22 #include <Library/DebugLib.h> 23 #include <Library/BaseMemoryLib.h> 24 #include <Library/UefiBootServicesTableLib.h> 25 26 /// 27 /// CRC32 Guided Section header 28 /// 29 typedef struct { 30 EFI_GUID_DEFINED_SECTION GuidedSectionHeader; ///< EFI guided section header 31 UINT32 CRC32Checksum; ///< 32bit CRC check sum 32 } CRC32_SECTION_HEADER; 33 34 typedef struct { 35 EFI_GUID_DEFINED_SECTION2 GuidedSectionHeader; ///< EFI guided section header 36 UINT32 CRC32Checksum; ///< 32bit CRC check sum 37 } CRC32_SECTION2_HEADER; 38 39 /** 40 41 GetInfo gets raw data size and attribute of the input guided section. 42 It first checks whether the input guid section is supported. 43 If not, EFI_INVALID_PARAMETER will return. 44 45 @param InputSection Buffer containing the input GUIDed section to be processed. 46 @param OutputBufferSize The size of OutputBuffer. 47 @param ScratchBufferSize The size of ScratchBuffer. 48 @param SectionAttribute The attribute of the input guided section. 49 50 @retval EFI_SUCCESS The size of destination buffer, the size of scratch buffer and 51 the attribute of the input section are successull retrieved. 52 @retval EFI_INVALID_PARAMETER The GUID in InputSection does not match this instance guid. 53 54 **/ 55 EFI_STATUS 56 EFIAPI 57 Crc32GuidedSectionGetInfo ( 58 IN CONST VOID *InputSection, 59 OUT UINT32 *OutputBufferSize, 60 OUT UINT32 *ScratchBufferSize, 61 OUT UINT16 *SectionAttribute 62 ) 63 { 64 if (IS_SECTION2 (InputSection)) { 65 // 66 // Check whether the input guid section is recognized. 67 // 68 if (!CompareGuid ( 69 &gEfiCrc32GuidedSectionExtractionGuid, 70 &(((EFI_GUID_DEFINED_SECTION2 *) InputSection)->SectionDefinitionGuid))) { 71 return EFI_INVALID_PARAMETER; 72 } 73 // 74 // Retrieve the size and attribute of the input section data. 75 // 76 *SectionAttribute = ((EFI_GUID_DEFINED_SECTION2 *) InputSection)->Attributes; 77 *ScratchBufferSize = 0; 78 *OutputBufferSize = SECTION2_SIZE (InputSection) - ((EFI_GUID_DEFINED_SECTION2 *) InputSection)->DataOffset; 79 } else { 80 // 81 // Check whether the input guid section is recognized. 82 // 83 if (!CompareGuid ( 84 &gEfiCrc32GuidedSectionExtractionGuid, 85 &(((EFI_GUID_DEFINED_SECTION *) InputSection)->SectionDefinitionGuid))) { 86 return EFI_INVALID_PARAMETER; 87 } 88 // 89 // Retrieve the size and attribute of the input section data. 90 // 91 *SectionAttribute = ((EFI_GUID_DEFINED_SECTION *) InputSection)->Attributes; 92 *ScratchBufferSize = 0; 93 *OutputBufferSize = SECTION_SIZE (InputSection) - ((EFI_GUID_DEFINED_SECTION *) InputSection)->DataOffset; 94 } 95 96 return EFI_SUCCESS; 97 } 98 99 /** 100 101 Extraction handler tries to extract raw data from the input guided section. 102 It also does authentication check for 32bit CRC value in the input guided section. 103 It first checks whether the input guid section is supported. 104 If not, EFI_INVALID_PARAMETER will return. 105 106 @param InputSection Buffer containing the input GUIDed section to be processed. 107 @param OutputBuffer Buffer to contain the output raw data allocated by the caller. 108 @param ScratchBuffer A pointer to a caller-allocated buffer for function internal use. 109 @param AuthenticationStatus A pointer to a caller-allocated UINT32 that indicates the 110 authentication status of the output buffer. 111 112 @retval EFI_SUCCESS Section Data and Auth Status is extracted successfully. 113 @retval EFI_INVALID_PARAMETER The GUID in InputSection does not match this instance guid. 114 115 **/ 116 EFI_STATUS 117 EFIAPI 118 Crc32GuidedSectionHandler ( 119 IN CONST VOID *InputSection, 120 OUT VOID **OutputBuffer, 121 IN VOID *ScratchBuffer, OPTIONAL 122 OUT UINT32 *AuthenticationStatus 123 ) 124 { 125 EFI_STATUS Status; 126 UINT32 SectionCrc32Checksum; 127 UINT32 Crc32Checksum; 128 UINT32 OutputBufferSize; 129 VOID *DummyInterface; 130 131 if (IS_SECTION2 (InputSection)) { 132 // 133 // Check whether the input guid section is recognized. 134 // 135 if (!CompareGuid ( 136 &gEfiCrc32GuidedSectionExtractionGuid, 137 &(((EFI_GUID_DEFINED_SECTION2 *) InputSection)->SectionDefinitionGuid))) { 138 return EFI_INVALID_PARAMETER; 139 } 140 141 // 142 // Get section Crc32 checksum. 143 // 144 SectionCrc32Checksum = ((CRC32_SECTION2_HEADER *) InputSection)->CRC32Checksum; 145 *OutputBuffer = (UINT8 *) InputSection + ((EFI_GUID_DEFINED_SECTION2 *) InputSection)->DataOffset; 146 OutputBufferSize = SECTION2_SIZE (InputSection) - ((EFI_GUID_DEFINED_SECTION2 *) InputSection)->DataOffset; 147 148 // 149 // Implicitly CRC32 GUIDed section should have STATUS_VALID bit set 150 // 151 ASSERT (((EFI_GUID_DEFINED_SECTION2 *) InputSection)->Attributes & EFI_GUIDED_SECTION_AUTH_STATUS_VALID); 152 *AuthenticationStatus = EFI_AUTH_STATUS_IMAGE_SIGNED; 153 } else { 154 // 155 // Check whether the input guid section is recognized. 156 // 157 if (!CompareGuid ( 158 &gEfiCrc32GuidedSectionExtractionGuid, 159 &(((EFI_GUID_DEFINED_SECTION *) InputSection)->SectionDefinitionGuid))) { 160 return EFI_INVALID_PARAMETER; 161 } 162 163 // 164 // Get section Crc32 checksum. 165 // 166 SectionCrc32Checksum = ((CRC32_SECTION_HEADER *) InputSection)->CRC32Checksum; 167 *OutputBuffer = (UINT8 *) InputSection + ((EFI_GUID_DEFINED_SECTION *) InputSection)->DataOffset; 168 OutputBufferSize = SECTION_SIZE (InputSection) - ((EFI_GUID_DEFINED_SECTION *) InputSection)->DataOffset; 169 170 // 171 // Implicitly CRC32 GUIDed section should have STATUS_VALID bit set 172 // 173 ASSERT (((EFI_GUID_DEFINED_SECTION *) InputSection)->Attributes & EFI_GUIDED_SECTION_AUTH_STATUS_VALID); 174 *AuthenticationStatus = EFI_AUTH_STATUS_IMAGE_SIGNED; 175 } 176 177 // 178 // Init Checksum value to Zero. 179 // 180 Crc32Checksum = 0; 181 182 // 183 // Check whether there exists EFI_SECURITY_POLICY_PROTOCOL_GUID. 184 // 185 Status = gBS->LocateProtocol (&gEfiSecurityPolicyProtocolGuid, NULL, &DummyInterface); 186 if (!EFI_ERROR (Status)) { 187 // 188 // If SecurityPolicy Protocol exist, AUTH platform override bit is set. 189 // 190 *AuthenticationStatus |= EFI_AUTH_STATUS_PLATFORM_OVERRIDE; 191 } else { 192 // 193 // Calculate CRC32 Checksum of Image 194 // 195 Status = gBS->CalculateCrc32 (*OutputBuffer, OutputBufferSize, &Crc32Checksum); 196 if (Status == EFI_SUCCESS) { 197 if (Crc32Checksum != SectionCrc32Checksum) { 198 // 199 // If Crc32 checksum is not matched, AUTH tested failed bit is set. 200 // 201 *AuthenticationStatus |= EFI_AUTH_STATUS_TEST_FAILED; 202 } 203 } else { 204 // 205 // If Crc32 checksum is not calculated, AUTH not tested bit is set. 206 // 207 *AuthenticationStatus |= EFI_AUTH_STATUS_NOT_TESTED; 208 } 209 } 210 211 return EFI_SUCCESS; 212 } 213 214 /** 215 Register the handler to extract CRC32 guided section. 216 217 @param ImageHandle ImageHandle of the loaded driver. 218 @param SystemTable Pointer to the EFI System Table. 219 220 @retval EFI_SUCCESS Register successfully. 221 @retval EFI_OUT_OF_RESOURCES No enough memory to register this handler. 222 **/ 223 EFI_STATUS 224 EFIAPI 225 DxeCrc32GuidedSectionExtractLibConstructor ( 226 IN EFI_HANDLE ImageHandle, 227 IN EFI_SYSTEM_TABLE *SystemTable 228 ) 229 { 230 return ExtractGuidedSectionRegisterHandlers ( 231 &gEfiCrc32GuidedSectionExtractionGuid, 232 Crc32GuidedSectionGetInfo, 233 Crc32GuidedSectionHandler 234 ); 235 } 236 237
