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 successfully retrieved.
52   @retval EFI_INVALID_PARAMETER  The GUID in InputSection does not match this instance guid.
53 
54 **/
55 EFI_STATUS
56 EFIAPI
Crc32GuidedSectionGetInfo(IN CONST VOID * InputSection,OUT UINT32 * OutputBufferSize,OUT UINT32 * ScratchBufferSize,OUT UINT16 * SectionAttribute)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
Crc32GuidedSectionHandler(IN CONST VOID * InputSection,OUT VOID ** OutputBuffer,IN VOID * ScratchBuffer,OPTIONAL OUT UINT32 * AuthenticationStatus)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
DxeCrc32GuidedSectionExtractLibConstructor(IN EFI_HANDLE ImageHandle,IN EFI_SYSTEM_TABLE * SystemTable)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