1 //===- MachO.h - MachO object file implementation ---------------*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file declares the MachOObjectFile class, which implement the ObjectFile
11 // interface for MachO files.
12 //
13 //===----------------------------------------------------------------------===//
14
15 #ifndef LLVM_OBJECT_MACHO_H
16 #define LLVM_OBJECT_MACHO_H
17
18 #include "llvm/ADT/ArrayRef.h"
19 #include "llvm/ADT/SmallVector.h"
20 #include "llvm/ADT/Triple.h"
21 #include "llvm/Object/ObjectFile.h"
22 #include "llvm/Support/MachO.h"
23
24 namespace llvm {
25 namespace object {
26
27 /// DiceRef - This is a value type class that represents a single
28 /// data in code entry in the table in a Mach-O object file.
29 class DiceRef {
30 DataRefImpl DicePimpl;
31 const ObjectFile *OwningObject;
32
33 public:
DiceRef()34 DiceRef() : OwningObject(nullptr) { }
35
36 DiceRef(DataRefImpl DiceP, const ObjectFile *Owner);
37
38 bool operator==(const DiceRef &Other) const;
39 bool operator<(const DiceRef &Other) const;
40
41 void moveNext();
42
43 std::error_code getOffset(uint32_t &Result) const;
44 std::error_code getLength(uint16_t &Result) const;
45 std::error_code getKind(uint16_t &Result) const;
46
47 DataRefImpl getRawDataRefImpl() const;
48 const ObjectFile *getObjectFile() const;
49 };
50 typedef content_iterator<DiceRef> dice_iterator;
51
52 /// ExportEntry encapsulates the current-state-of-the-walk used when doing a
53 /// non-recursive walk of the trie data structure. This allows you to iterate
54 /// across all exported symbols using:
55 /// for (const llvm::object::ExportEntry &AnExport : Obj->exports()) {
56 /// }
57 class ExportEntry {
58 public:
59 ExportEntry(ArrayRef<uint8_t> Trie);
60
61 StringRef name() const;
62 uint64_t flags() const;
63 uint64_t address() const;
64 uint64_t other() const;
65 StringRef otherName() const;
66 uint32_t nodeOffset() const;
67
68 bool operator==(const ExportEntry &) const;
69
70 void moveNext();
71
72 private:
73 friend class MachOObjectFile;
74 void moveToFirst();
75 void moveToEnd();
76 uint64_t readULEB128(const uint8_t *&p);
77 void pushDownUntilBottom();
78 void pushNode(uint64_t Offset);
79
80 // Represents a node in the mach-o exports trie.
81 struct NodeState {
82 NodeState(const uint8_t *Ptr);
83 const uint8_t *Start;
84 const uint8_t *Current;
85 uint64_t Flags;
86 uint64_t Address;
87 uint64_t Other;
88 const char *ImportName;
89 unsigned ChildCount;
90 unsigned NextChildIndex;
91 unsigned ParentStringLength;
92 bool IsExportNode;
93 };
94
95 ArrayRef<uint8_t> Trie;
96 SmallString<256> CumulativeString;
97 SmallVector<NodeState, 16> Stack;
98 bool Malformed;
99 bool Done;
100 };
101 typedef content_iterator<ExportEntry> export_iterator;
102
103 /// MachORebaseEntry encapsulates the current state in the decompression of
104 /// rebasing opcodes. This allows you to iterate through the compressed table of
105 /// rebasing using:
106 /// for (const llvm::object::MachORebaseEntry &Entry : Obj->rebaseTable()) {
107 /// }
108 class MachORebaseEntry {
109 public:
110 MachORebaseEntry(ArrayRef<uint8_t> opcodes, bool is64Bit);
111
112 uint32_t segmentIndex() const;
113 uint64_t segmentOffset() const;
114 StringRef typeName() const;
115
116 bool operator==(const MachORebaseEntry &) const;
117
118 void moveNext();
119
120 private:
121 friend class MachOObjectFile;
122 void moveToFirst();
123 void moveToEnd();
124 uint64_t readULEB128();
125
126 ArrayRef<uint8_t> Opcodes;
127 const uint8_t *Ptr;
128 uint64_t SegmentOffset;
129 uint32_t SegmentIndex;
130 uint64_t RemainingLoopCount;
131 uint64_t AdvanceAmount;
132 uint8_t RebaseType;
133 uint8_t PointerSize;
134 bool Malformed;
135 bool Done;
136 };
137 typedef content_iterator<MachORebaseEntry> rebase_iterator;
138
139 /// MachOBindEntry encapsulates the current state in the decompression of
140 /// binding opcodes. This allows you to iterate through the compressed table of
141 /// bindings using:
142 /// for (const llvm::object::MachOBindEntry &Entry : Obj->bindTable()) {
143 /// }
144 class MachOBindEntry {
145 public:
146 enum class Kind { Regular, Lazy, Weak };
147
148 MachOBindEntry(ArrayRef<uint8_t> Opcodes, bool is64Bit, MachOBindEntry::Kind);
149
150 uint32_t segmentIndex() const;
151 uint64_t segmentOffset() const;
152 StringRef typeName() const;
153 StringRef symbolName() const;
154 uint32_t flags() const;
155 int64_t addend() const;
156 int ordinal() const;
157
158 bool operator==(const MachOBindEntry &) const;
159
160 void moveNext();
161
162 private:
163 friend class MachOObjectFile;
164 void moveToFirst();
165 void moveToEnd();
166 uint64_t readULEB128();
167 int64_t readSLEB128();
168
169 ArrayRef<uint8_t> Opcodes;
170 const uint8_t *Ptr;
171 uint64_t SegmentOffset;
172 uint32_t SegmentIndex;
173 StringRef SymbolName;
174 int Ordinal;
175 uint32_t Flags;
176 int64_t Addend;
177 uint64_t RemainingLoopCount;
178 uint64_t AdvanceAmount;
179 uint8_t BindType;
180 uint8_t PointerSize;
181 Kind TableKind;
182 bool Malformed;
183 bool Done;
184 };
185 typedef content_iterator<MachOBindEntry> bind_iterator;
186
187 class MachOObjectFile : public ObjectFile {
188 public:
189 struct LoadCommandInfo {
190 const char *Ptr; // Where in memory the load command is.
191 MachO::load_command C; // The command itself.
192 };
193
194 MachOObjectFile(MemoryBufferRef Object, bool IsLittleEndian, bool Is64Bits,
195 std::error_code &EC);
196
197 void moveSymbolNext(DataRefImpl &Symb) const override;
198 std::error_code getSymbolName(DataRefImpl Symb,
199 StringRef &Res) const override;
200
201 // MachO specific.
202 std::error_code getIndirectName(DataRefImpl Symb, StringRef &Res) const;
203 unsigned getSectionType(SectionRef Sec) const;
204
205 std::error_code getSymbolAddress(DataRefImpl Symb,
206 uint64_t &Res) const override;
207 std::error_code getSymbolAlignment(DataRefImpl Symb,
208 uint32_t &Res) const override;
209 std::error_code getSymbolSize(DataRefImpl Symb, uint64_t &Res) const override;
210 std::error_code getSymbolType(DataRefImpl Symb,
211 SymbolRef::Type &Res) const override;
212 uint32_t getSymbolFlags(DataRefImpl Symb) const override;
213 std::error_code getSymbolSection(DataRefImpl Symb,
214 section_iterator &Res) const override;
215
216 void moveSectionNext(DataRefImpl &Sec) const override;
217 std::error_code getSectionName(DataRefImpl Sec,
218 StringRef &Res) const override;
219 uint64_t getSectionAddress(DataRefImpl Sec) const override;
220 uint64_t getSectionSize(DataRefImpl Sec) const override;
221 std::error_code getSectionContents(DataRefImpl Sec,
222 StringRef &Res) const override;
223 uint64_t getSectionAlignment(DataRefImpl Sec) const override;
224 bool isSectionText(DataRefImpl Sec) const override;
225 bool isSectionData(DataRefImpl Sec) const override;
226 bool isSectionBSS(DataRefImpl Sec) const override;
227 bool isSectionVirtual(DataRefImpl Sec) const override;
228 bool sectionContainsSymbol(DataRefImpl Sec, DataRefImpl Symb) const override;
229 relocation_iterator section_rel_begin(DataRefImpl Sec) const override;
230 relocation_iterator section_rel_end(DataRefImpl Sec) const override;
231
232 void moveRelocationNext(DataRefImpl &Rel) const override;
233 std::error_code getRelocationAddress(DataRefImpl Rel,
234 uint64_t &Res) const override;
235 std::error_code getRelocationOffset(DataRefImpl Rel,
236 uint64_t &Res) const override;
237 symbol_iterator getRelocationSymbol(DataRefImpl Rel) const override;
238 std::error_code getRelocationType(DataRefImpl Rel,
239 uint64_t &Res) const override;
240 std::error_code
241 getRelocationTypeName(DataRefImpl Rel,
242 SmallVectorImpl<char> &Result) const override;
243 std::error_code
244 getRelocationValueString(DataRefImpl Rel,
245 SmallVectorImpl<char> &Result) const override;
246 std::error_code getRelocationHidden(DataRefImpl Rel,
247 bool &Result) const override;
248
249 // MachO specific.
250 std::error_code getLibraryShortNameByIndex(unsigned Index, StringRef &) const;
251
252 // TODO: Would be useful to have an iterator based version
253 // of the load command interface too.
254
255 basic_symbol_iterator symbol_begin_impl() const override;
256 basic_symbol_iterator symbol_end_impl() const override;
257
258 // MachO specific.
259 basic_symbol_iterator getSymbolByIndex(unsigned Index) const;
260
261 section_iterator section_begin() const override;
262 section_iterator section_end() const override;
263
264 uint8_t getBytesInAddress() const override;
265
266 StringRef getFileFormatName() const override;
267 unsigned getArch() const override;
268 Triple getArch(const char **McpuDefault, Triple *ThumbTriple) const;
269
270 relocation_iterator section_rel_begin(unsigned Index) const;
271 relocation_iterator section_rel_end(unsigned Index) const;
272
273 dice_iterator begin_dices() const;
274 dice_iterator end_dices() const;
275
276 /// For use iterating over all exported symbols.
277 iterator_range<export_iterator> exports() const;
278
279 /// For use examining a trie not in a MachOObjectFile.
280 static iterator_range<export_iterator> exports(ArrayRef<uint8_t> Trie);
281
282 /// For use iterating over all rebase table entries.
283 iterator_range<rebase_iterator> rebaseTable() const;
284
285 /// For use examining rebase opcodes not in a MachOObjectFile.
286 static iterator_range<rebase_iterator> rebaseTable(ArrayRef<uint8_t> Opcodes,
287 bool is64);
288
289 /// For use iterating over all bind table entries.
290 iterator_range<bind_iterator> bindTable() const;
291
292 /// For use iterating over all lazy bind table entries.
293 iterator_range<bind_iterator> lazyBindTable() const;
294
295 /// For use iterating over all lazy bind table entries.
296 iterator_range<bind_iterator> weakBindTable() const;
297
298 /// For use examining bind opcodes not in a MachOObjectFile.
299 static iterator_range<bind_iterator> bindTable(ArrayRef<uint8_t> Opcodes,
300 bool is64,
301 MachOBindEntry::Kind);
302
303
304 // In a MachO file, sections have a segment name. This is used in the .o
305 // files. They have a single segment, but this field specifies which segment
306 // a section should be put in in the final object.
307 StringRef getSectionFinalSegmentName(DataRefImpl Sec) const;
308
309 // Names are stored as 16 bytes. These returns the raw 16 bytes without
310 // interpreting them as a C string.
311 ArrayRef<char> getSectionRawName(DataRefImpl Sec) const;
312 ArrayRef<char> getSectionRawFinalSegmentName(DataRefImpl Sec) const;
313
314 // MachO specific Info about relocations.
315 bool isRelocationScattered(const MachO::any_relocation_info &RE) const;
316 unsigned getPlainRelocationSymbolNum(
317 const MachO::any_relocation_info &RE) const;
318 bool getPlainRelocationExternal(const MachO::any_relocation_info &RE) const;
319 bool getScatteredRelocationScattered(
320 const MachO::any_relocation_info &RE) const;
321 uint32_t getScatteredRelocationValue(
322 const MachO::any_relocation_info &RE) const;
323 uint32_t getScatteredRelocationType(
324 const MachO::any_relocation_info &RE) const;
325 unsigned getAnyRelocationAddress(const MachO::any_relocation_info &RE) const;
326 unsigned getAnyRelocationPCRel(const MachO::any_relocation_info &RE) const;
327 unsigned getAnyRelocationLength(const MachO::any_relocation_info &RE) const;
328 unsigned getAnyRelocationType(const MachO::any_relocation_info &RE) const;
329 SectionRef getRelocationSection(const MachO::any_relocation_info &RE) const;
330
331 // Walk load commands.
332 LoadCommandInfo getFirstLoadCommandInfo() const;
333 LoadCommandInfo getNextLoadCommandInfo(const LoadCommandInfo &L) const;
334
335 // MachO specific structures.
336 MachO::section getSection(DataRefImpl DRI) const;
337 MachO::section_64 getSection64(DataRefImpl DRI) const;
338 MachO::section getSection(const LoadCommandInfo &L, unsigned Index) const;
339 MachO::section_64 getSection64(const LoadCommandInfo &L,unsigned Index) const;
340 MachO::nlist getSymbolTableEntry(DataRefImpl DRI) const;
341 MachO::nlist_64 getSymbol64TableEntry(DataRefImpl DRI) const;
342
343 MachO::linkedit_data_command
344 getLinkeditDataLoadCommand(const LoadCommandInfo &L) const;
345 MachO::segment_command
346 getSegmentLoadCommand(const LoadCommandInfo &L) const;
347 MachO::segment_command_64
348 getSegment64LoadCommand(const LoadCommandInfo &L) const;
349 MachO::linker_option_command
350 getLinkerOptionLoadCommand(const LoadCommandInfo &L) const;
351 MachO::version_min_command
352 getVersionMinLoadCommand(const LoadCommandInfo &L) const;
353 MachO::dylib_command
354 getDylibIDLoadCommand(const LoadCommandInfo &L) const;
355 MachO::dyld_info_command
356 getDyldInfoLoadCommand(const LoadCommandInfo &L) const;
357 MachO::dylinker_command
358 getDylinkerCommand(const LoadCommandInfo &L) const;
359 MachO::uuid_command
360 getUuidCommand(const LoadCommandInfo &L) const;
361 MachO::rpath_command
362 getRpathCommand(const LoadCommandInfo &L) const;
363 MachO::source_version_command
364 getSourceVersionCommand(const LoadCommandInfo &L) const;
365 MachO::entry_point_command
366 getEntryPointCommand(const LoadCommandInfo &L) const;
367 MachO::encryption_info_command
368 getEncryptionInfoCommand(const LoadCommandInfo &L) const;
369 MachO::encryption_info_command_64
370 getEncryptionInfoCommand64(const LoadCommandInfo &L) const;
371 MachO::sub_framework_command
372 getSubFrameworkCommand(const LoadCommandInfo &L) const;
373 MachO::sub_umbrella_command
374 getSubUmbrellaCommand(const LoadCommandInfo &L) const;
375 MachO::sub_library_command
376 getSubLibraryCommand(const LoadCommandInfo &L) const;
377 MachO::sub_client_command
378 getSubClientCommand(const LoadCommandInfo &L) const;
379 MachO::routines_command
380 getRoutinesCommand(const LoadCommandInfo &L) const;
381 MachO::routines_command_64
382 getRoutinesCommand64(const LoadCommandInfo &L) const;
383 MachO::thread_command
384 getThreadCommand(const LoadCommandInfo &L) const;
385
386 MachO::any_relocation_info getRelocation(DataRefImpl Rel) const;
387 MachO::data_in_code_entry getDice(DataRefImpl Rel) const;
388 MachO::mach_header getHeader() const;
389 MachO::mach_header_64 getHeader64() const;
390 uint32_t
391 getIndirectSymbolTableEntry(const MachO::dysymtab_command &DLC,
392 unsigned Index) const;
393 MachO::data_in_code_entry getDataInCodeTableEntry(uint32_t DataOffset,
394 unsigned Index) const;
395 MachO::symtab_command getSymtabLoadCommand() const;
396 MachO::dysymtab_command getDysymtabLoadCommand() const;
397 MachO::linkedit_data_command getDataInCodeLoadCommand() const;
398 MachO::linkedit_data_command getLinkOptHintsLoadCommand() const;
399 ArrayRef<uint8_t> getDyldInfoRebaseOpcodes() const;
400 ArrayRef<uint8_t> getDyldInfoBindOpcodes() const;
401 ArrayRef<uint8_t> getDyldInfoWeakBindOpcodes() const;
402 ArrayRef<uint8_t> getDyldInfoLazyBindOpcodes() const;
403 ArrayRef<uint8_t> getDyldInfoExportsTrie() const;
404 ArrayRef<uint8_t> getUuid() const;
405
406 StringRef getStringTableData() const;
407 bool is64Bit() const;
408 void ReadULEB128s(uint64_t Index, SmallVectorImpl<uint64_t> &Out) const;
409
410 static StringRef guessLibraryShortName(StringRef Name, bool &isFramework,
411 StringRef &Suffix);
412
413 static Triple::ArchType getArch(uint32_t CPUType);
414 static Triple getArch(uint32_t CPUType, uint32_t CPUSubType,
415 const char **McpuDefault = nullptr);
416 static Triple getThumbArch(uint32_t CPUType, uint32_t CPUSubType,
417 const char **McpuDefault = nullptr);
418 static Triple getArch(uint32_t CPUType, uint32_t CPUSubType,
419 const char **McpuDefault, Triple *ThumbTriple);
420 static bool isValidArch(StringRef ArchFlag);
421 static Triple getHostArch();
422
423 bool isRelocatableObject() const override;
424
hasPageZeroSegment()425 bool hasPageZeroSegment() const { return HasPageZeroSegment; }
426
classof(const Binary * v)427 static bool classof(const Binary *v) {
428 return v->isMachO();
429 }
430
431 private:
432 typedef SmallVector<const char*, 1> SectionList;
433 SectionList Sections;
434 typedef SmallVector<const char*, 1> LibraryList;
435 LibraryList Libraries;
436 typedef SmallVector<StringRef, 1> LibraryShortName;
437 mutable LibraryShortName LibrariesShortNames;
438 const char *SymtabLoadCmd;
439 const char *DysymtabLoadCmd;
440 const char *DataInCodeLoadCmd;
441 const char *LinkOptHintsLoadCmd;
442 const char *DyldInfoLoadCmd;
443 const char *UuidLoadCmd;
444 bool HasPageZeroSegment;
445 };
446
447 /// DiceRef
DiceRef(DataRefImpl DiceP,const ObjectFile * Owner)448 inline DiceRef::DiceRef(DataRefImpl DiceP, const ObjectFile *Owner)
449 : DicePimpl(DiceP) , OwningObject(Owner) {}
450
451 inline bool DiceRef::operator==(const DiceRef &Other) const {
452 return DicePimpl == Other.DicePimpl;
453 }
454
455 inline bool DiceRef::operator<(const DiceRef &Other) const {
456 return DicePimpl < Other.DicePimpl;
457 }
458
moveNext()459 inline void DiceRef::moveNext() {
460 const MachO::data_in_code_entry *P =
461 reinterpret_cast<const MachO::data_in_code_entry *>(DicePimpl.p);
462 DicePimpl.p = reinterpret_cast<uintptr_t>(P + 1);
463 }
464
465 // Since a Mach-O data in code reference, a DiceRef, can only be created when
466 // the OwningObject ObjectFile is a MachOObjectFile a static_cast<> is used for
467 // the methods that get the values of the fields of the reference.
468
getOffset(uint32_t & Result)469 inline std::error_code DiceRef::getOffset(uint32_t &Result) const {
470 const MachOObjectFile *MachOOF =
471 static_cast<const MachOObjectFile *>(OwningObject);
472 MachO::data_in_code_entry Dice = MachOOF->getDice(DicePimpl);
473 Result = Dice.offset;
474 return object_error::success;
475 }
476
getLength(uint16_t & Result)477 inline std::error_code DiceRef::getLength(uint16_t &Result) const {
478 const MachOObjectFile *MachOOF =
479 static_cast<const MachOObjectFile *>(OwningObject);
480 MachO::data_in_code_entry Dice = MachOOF->getDice(DicePimpl);
481 Result = Dice.length;
482 return object_error::success;
483 }
484
getKind(uint16_t & Result)485 inline std::error_code DiceRef::getKind(uint16_t &Result) const {
486 const MachOObjectFile *MachOOF =
487 static_cast<const MachOObjectFile *>(OwningObject);
488 MachO::data_in_code_entry Dice = MachOOF->getDice(DicePimpl);
489 Result = Dice.kind;
490 return object_error::success;
491 }
492
getRawDataRefImpl()493 inline DataRefImpl DiceRef::getRawDataRefImpl() const {
494 return DicePimpl;
495 }
496
getObjectFile()497 inline const ObjectFile *DiceRef::getObjectFile() const {
498 return OwningObject;
499 }
500
501 }
502 }
503
504 #endif
505
506