1 /** @file
2
3 Copyright (c) 2015, Intel Corporation. All rights reserved.<BR>
4 Copyright (c) 2016 - 2018, ARM Limited. All rights reserved.<BR>
5
6 SPDX-License-Identifier: BSD-2-Clause-Patent
7
8 **/
9
10 #include <Library/FvLib.h>
11
12 #include <Library/BaseLib.h>
13 #include <Library/BaseMemoryLib.h>
14 #include <Library/DebugLib.h>
15
16 #define GET_OCCUPIED_SIZE(ActualSize, Alignment) \
17 (ActualSize) + (((Alignment) - ((ActualSize) & ((Alignment) - 1))) & ((Alignment) - 1))
18
19 /**
20 Returns the highest bit set of the State field
21
22 @param ErasePolarity Erase Polarity as defined by EFI_FVB_ERASE_POLARITY
23 in the Attributes field.
24 @param FfsHeader Pointer to FFS File Header.
25
26 @return the highest bit in the State field
27 **/
28 EFI_FFS_FILE_STATE
GetFileState(IN UINT8 ErasePolarity,IN EFI_FFS_FILE_HEADER * FfsHeader)29 GetFileState (
30 IN UINT8 ErasePolarity,
31 IN EFI_FFS_FILE_HEADER *FfsHeader
32 )
33 {
34 EFI_FFS_FILE_STATE FileState;
35 EFI_FFS_FILE_STATE HighestBit;
36
37 FileState = FfsHeader->State;
38
39 if (ErasePolarity != 0) {
40 FileState = (EFI_FFS_FILE_STATE)~FileState;
41 }
42
43 HighestBit = 0x80;
44 while (HighestBit != 0 && (HighestBit & FileState) == 0) {
45 HighestBit >>= 1;
46 }
47
48 return HighestBit;
49 }
50
51 /**
52 Calculates the checksum of the header of a file.
53
54 @param FileHeader Pointer to FFS File Header.
55
56 @return Checksum of the header.
57 **/
58 UINT8
CalculateHeaderChecksum(IN EFI_FFS_FILE_HEADER * FileHeader)59 CalculateHeaderChecksum (
60 IN EFI_FFS_FILE_HEADER *FileHeader
61 )
62 {
63 UINT8 *ptr;
64 UINTN Index;
65 UINT8 Sum;
66
67 Sum = 0;
68 ptr = (UINT8 *) FileHeader;
69
70 for (Index = 0; Index < sizeof (EFI_FFS_FILE_HEADER) - 3; Index += 4) {
71 Sum = (UINT8) (Sum + ptr[Index]);
72 Sum = (UINT8) (Sum + ptr[Index + 1]);
73 Sum = (UINT8) (Sum + ptr[Index + 2]);
74 Sum = (UINT8) (Sum + ptr[Index + 3]);
75 }
76
77 for (; Index < sizeof (EFI_FFS_FILE_HEADER); Index++) {
78 Sum = (UINT8) (Sum + ptr[Index]);
79 }
80 //
81 // State field (since this indicates the different state of file).
82 //
83 Sum = (UINT8) (Sum - FileHeader->State);
84 //
85 // Checksum field of the file is not part of the header checksum.
86 //
87 Sum = (UINT8) (Sum - FileHeader->IntegrityCheck.Checksum.File);
88
89 return Sum;
90 }
91
92 /**
93 Given the input file pointer, search for the next matching file in the
94 FFS volume as defined by SearchType. The search starts from FileHeader inside
95 the Firmware Volume defined by FwVolHeader.
96
97 @param SearchType Filter to find only files of this type.
98 Type EFI_FV_FILETYPE_ALL causes no filtering to be done.
99 @param FwVolHeader Pointer to the FV header of the volume to search.
100 This parameter must point to a valid FFS volume.
101 @param FileHeader Pointer to the current file from which to begin searching.
102 This pointer will be updated upon return to reflect the file found.
103
104 @retval EFI_NOT_FOUND No files matching the search criteria were found
105 @retval EFI_SUCCESS
106 **/
107 EFI_STATUS
108 EFIAPI
FfsFindNextFile(IN EFI_FV_FILETYPE SearchType,IN EFI_FIRMWARE_VOLUME_HEADER * FwVolHeader,IN OUT EFI_FFS_FILE_HEADER ** FileHeader)109 FfsFindNextFile (
110 IN EFI_FV_FILETYPE SearchType,
111 IN EFI_FIRMWARE_VOLUME_HEADER *FwVolHeader,
112 IN OUT EFI_FFS_FILE_HEADER **FileHeader
113 )
114 {
115 EFI_FIRMWARE_VOLUME_EXT_HEADER *FvExtHeader;
116
117 EFI_FFS_FILE_HEADER *FfsFileHeader;
118 UINT32 FileLength;
119 UINT32 FileOccupiedSize;
120 UINT32 FileOffset;
121 UINT64 FvLength;
122 UINT8 ErasePolarity;
123 UINT8 FileState;
124
125 FvLength = FwVolHeader->FvLength;
126 if (FwVolHeader->Attributes & EFI_FVB2_ERASE_POLARITY) {
127 ErasePolarity = 1;
128 } else {
129 ErasePolarity = 0;
130 }
131 //
132 // If FileHeader is not specified (NULL) start with the first file in the
133 // firmware volume. Otherwise, start from the FileHeader.
134 //
135 if (*FileHeader == NULL) {
136
137 if (FwVolHeader->ExtHeaderOffset != 0) {
138
139 FvExtHeader = (EFI_FIRMWARE_VOLUME_EXT_HEADER *)((UINT8 *)FwVolHeader +
140 FwVolHeader->ExtHeaderOffset);
141
142 FfsFileHeader = (EFI_FFS_FILE_HEADER *)((UINT8 *)FvExtHeader +
143 FvExtHeader->ExtHeaderSize);
144
145 } else {
146
147 FfsFileHeader = (EFI_FFS_FILE_HEADER *)((UINT8 *)FwVolHeader +
148 FwVolHeader->HeaderLength);
149
150 }
151
152 FfsFileHeader = (EFI_FFS_FILE_HEADER *)((UINTN)FwVolHeader +
153 ALIGN_VALUE((UINTN)FfsFileHeader -
154 (UINTN)FwVolHeader, 8));
155 } else {
156 //
157 // Length is 24 bits wide so mask upper 8 bits
158 // FileLength is adjusted to FileOccupiedSize as it is 8 byte aligned.
159 //
160 FileLength = FFS_FILE_SIZE(*FileHeader);
161 FileOccupiedSize = GET_OCCUPIED_SIZE (FileLength, 8);
162 FfsFileHeader = (EFI_FFS_FILE_HEADER *) ((UINT8 *) *FileHeader + FileOccupiedSize);
163 }
164
165 FileOffset = (UINT32) ((UINT8 *) FfsFileHeader - (UINT8 *) FwVolHeader);
166
167 while (FileOffset < (FvLength - sizeof (EFI_FFS_FILE_HEADER))) {
168 //
169 // Get FileState which is the highest bit of the State
170 //
171 FileState = GetFileState (ErasePolarity, FfsFileHeader);
172
173 switch (FileState) {
174
175 case EFI_FILE_HEADER_INVALID:
176 FileOffset += sizeof (EFI_FFS_FILE_HEADER);
177 FfsFileHeader = (EFI_FFS_FILE_HEADER *) ((UINT8 *) FfsFileHeader + sizeof (EFI_FFS_FILE_HEADER));
178 break;
179
180 case EFI_FILE_DATA_VALID:
181 case EFI_FILE_MARKED_FOR_UPDATE:
182 if (CalculateHeaderChecksum (FfsFileHeader) == 0) {
183 FileLength = FFS_FILE_SIZE(FfsFileHeader);
184 FileOccupiedSize = GET_OCCUPIED_SIZE (FileLength, 8);
185
186 if ((SearchType == FfsFileHeader->Type) || (SearchType == EFI_FV_FILETYPE_ALL)) {
187
188 *FileHeader = FfsFileHeader;
189
190 return EFI_SUCCESS;
191 }
192
193 FileOffset += FileOccupiedSize;
194 FfsFileHeader = (EFI_FFS_FILE_HEADER *) ((UINT8 *) FfsFileHeader + FileOccupiedSize);
195 } else {
196 return EFI_NOT_FOUND;
197 }
198 break;
199
200 case EFI_FILE_DELETED:
201 FileLength = FFS_FILE_SIZE(FfsFileHeader);
202 FileOccupiedSize = GET_OCCUPIED_SIZE (FileLength, 8);
203 FileOffset += FileOccupiedSize;
204 FfsFileHeader = (EFI_FFS_FILE_HEADER *) ((UINT8 *) FfsFileHeader + FileOccupiedSize);
205 break;
206
207 default:
208 return EFI_NOT_FOUND;
209
210 }
211 }
212
213 return EFI_NOT_FOUND;
214 }
215
216 /**
217 Locates a section within a series of sections
218 with the specified section type.
219
220 @param[in] Sections The sections to search
221 @param[in] SizeOfSections Total size of all sections
222 @param[in] SectionType The section type to locate
223 @param[out] FoundSection The FFS section if found
224
225 @retval EFI_SUCCESS The file and section was found
226 @retval EFI_NOT_FOUND The file and section was not found
227 @retval EFI_VOLUME_CORRUPTED The firmware volume was corrupted
228 **/
229 EFI_STATUS
230 EFIAPI
FindFfsSectionInSections(IN VOID * Sections,IN UINTN SizeOfSections,IN EFI_SECTION_TYPE SectionType,OUT EFI_COMMON_SECTION_HEADER ** FoundSection)231 FindFfsSectionInSections (
232 IN VOID *Sections,
233 IN UINTN SizeOfSections,
234 IN EFI_SECTION_TYPE SectionType,
235 OUT EFI_COMMON_SECTION_HEADER **FoundSection
236 )
237 {
238 EFI_PHYSICAL_ADDRESS CurrentAddress;
239 UINT32 Size;
240 EFI_PHYSICAL_ADDRESS EndOfSections;
241 EFI_COMMON_SECTION_HEADER *Section;
242 EFI_PHYSICAL_ADDRESS EndOfSection;
243
244 //
245 // Loop through the FFS file sections
246 //
247 EndOfSection = (EFI_PHYSICAL_ADDRESS)(UINTN) Sections;
248 EndOfSections = EndOfSection + SizeOfSections;
249 for (;;) {
250 if (EndOfSection == EndOfSections) {
251 break;
252 }
253 CurrentAddress = EndOfSection;
254
255 Section = (EFI_COMMON_SECTION_HEADER*)(UINTN) CurrentAddress;
256
257 Size = SECTION_SIZE (Section);
258 if (Size < sizeof (*Section)) {
259 return EFI_VOLUME_CORRUPTED;
260 }
261
262 EndOfSection = CurrentAddress + Size;
263 if (EndOfSection > EndOfSections) {
264 return EFI_VOLUME_CORRUPTED;
265 }
266 Size = GET_OCCUPIED_SIZE (Size, 4);
267
268 //
269 // Look for the requested section type
270 //
271 if (Section->Type == SectionType) {
272 *FoundSection = Section;
273 return EFI_SUCCESS;
274 }
275 }
276
277 return EFI_NOT_FOUND;
278 }
279
280 /**
281 Given the input file pointer, search for the next matching section in the
282 FFS volume.
283
284 @param SearchType Filter to find only sections of this type.
285 @param FfsFileHeader Pointer to the current file to search.
286 @param SectionHeader Pointer to the Section matching SectionType in FfsFileHeader.
287 NULL if section not found
288
289 @retval EFI_NOT_FOUND No files matching the search criteria were found
290 @retval EFI_SUCCESS
291 **/
292 EFI_STATUS
293 EFIAPI
FfsFindSection(IN EFI_SECTION_TYPE SectionType,IN EFI_FFS_FILE_HEADER * FfsFileHeader,IN OUT EFI_COMMON_SECTION_HEADER ** SectionHeader)294 FfsFindSection (
295 IN EFI_SECTION_TYPE SectionType,
296 IN EFI_FFS_FILE_HEADER *FfsFileHeader,
297 IN OUT EFI_COMMON_SECTION_HEADER **SectionHeader
298 )
299 {
300 UINT32 FileSize;
301 EFI_COMMON_SECTION_HEADER *Section;
302 EFI_STATUS Status;
303
304 //
305 // Size is 24 bits wide so mask upper 8 bits.
306 // Does not include FfsFileHeader header size
307 // FileSize is adjusted to FileOccupiedSize as it is 8 byte aligned.
308 //
309 Section = (EFI_COMMON_SECTION_HEADER *) (FfsFileHeader + 1);
310 FileSize = FFS_FILE_SIZE(FfsFileHeader);
311 FileSize -= sizeof (EFI_FFS_FILE_HEADER);
312
313 Status = FindFfsSectionInSections (
314 Section,
315 FileSize,
316 SectionType,
317 SectionHeader
318 );
319 return Status;
320 }
321
322 /**
323 Given the input file pointer, search for the next matching section in the
324 FFS volume.
325
326 @param SearchType Filter to find only sections of this type.
327 @param FfsFileHeader Pointer to the current file to search.
328 @param SectionData Pointer to the Section matching SectionType in FfsFileHeader.
329 NULL if section not found
330 @param SectionDataSize The size of SectionData
331
332 @retval EFI_NOT_FOUND No files matching the search criteria were found
333 @retval EFI_SUCCESS
334 **/
335 EFI_STATUS
336 EFIAPI
FfsFindSectionData(IN EFI_SECTION_TYPE SectionType,IN EFI_FFS_FILE_HEADER * FfsFileHeader,IN OUT VOID ** SectionData,IN OUT UINTN * SectionDataSize)337 FfsFindSectionData (
338 IN EFI_SECTION_TYPE SectionType,
339 IN EFI_FFS_FILE_HEADER *FfsFileHeader,
340 IN OUT VOID **SectionData,
341 IN OUT UINTN *SectionDataSize
342 )
343 {
344 UINT32 FileSize;
345 EFI_COMMON_SECTION_HEADER *Section;
346 UINT32 SectionLength;
347 UINT32 ParsedLength;
348
349 //
350 // Size is 24 bits wide so mask upper 8 bits.
351 // Does not include FfsFileHeader header size
352 // FileSize is adjusted to FileOccupiedSize as it is 8 byte aligned.
353 //
354 Section = (EFI_COMMON_SECTION_HEADER *) (FfsFileHeader + 1);
355 FileSize = FFS_FILE_SIZE(FfsFileHeader);
356 FileSize -= sizeof (EFI_FFS_FILE_HEADER);
357
358 *SectionData = NULL;
359 ParsedLength = 0;
360 while (ParsedLength < FileSize) {
361 if (Section->Type == SectionType) {
362 *SectionData = (VOID *) (Section + 1);
363 *SectionDataSize = SECTION_SIZE(Section);
364 return EFI_SUCCESS;
365 }
366 //
367 // Size is 24 bits wide so mask upper 8 bits.
368 // SectionLength is adjusted it is 4 byte aligned.
369 // Go to the next section
370 //
371 SectionLength = SECTION_SIZE(Section);
372 SectionLength = GET_OCCUPIED_SIZE (SectionLength, 4);
373
374 ParsedLength += SectionLength;
375 Section = (EFI_COMMON_SECTION_HEADER *) ((UINT8 *) Section + SectionLength);
376 }
377
378 return EFI_NOT_FOUND;
379 }
380