1 //===- MachO.h - MachO object file implementation ---------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file declares the MachOObjectFile class, which implement the ObjectFile
10 // interface for MachO files.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #ifndef LLVM_OBJECT_MACHO_H
15 #define LLVM_OBJECT_MACHO_H
16
17 #include "llvm/ADT/ArrayRef.h"
18 #include "llvm/ADT/SmallString.h"
19 #include "llvm/ADT/SmallVector.h"
20 #include "llvm/ADT/StringExtras.h"
21 #include "llvm/ADT/StringRef.h"
22 #include "llvm/ADT/iterator_range.h"
23 #include "llvm/BinaryFormat/MachO.h"
24 #include "llvm/BinaryFormat/Swift.h"
25 #include "llvm/Object/Binary.h"
26 #include "llvm/Object/ObjectFile.h"
27 #include "llvm/Object/SymbolicFile.h"
28 #include "llvm/Support/Error.h"
29 #include "llvm/Support/Format.h"
30 #include "llvm/Support/MemoryBuffer.h"
31 #include "llvm/Support/raw_ostream.h"
32 #include "llvm/TargetParser/SubtargetFeature.h"
33 #include "llvm/TargetParser/Triple.h"
34 #include <cstdint>
35 #include <memory>
36 #include <string>
37 #include <system_error>
38
39 namespace llvm {
40 namespace object {
41
42 /// DiceRef - This is a value type class that represents a single
43 /// data in code entry in the table in a Mach-O object file.
44 class DiceRef {
45 DataRefImpl DicePimpl;
46 const ObjectFile *OwningObject = nullptr;
47
48 public:
49 DiceRef() = default;
50 DiceRef(DataRefImpl DiceP, const ObjectFile *Owner);
51
52 bool operator==(const DiceRef &Other) const;
53 bool operator<(const DiceRef &Other) const;
54
55 void moveNext();
56
57 std::error_code getOffset(uint32_t &Result) const;
58 std::error_code getLength(uint16_t &Result) const;
59 std::error_code getKind(uint16_t &Result) const;
60
61 DataRefImpl getRawDataRefImpl() const;
62 const ObjectFile *getObjectFile() const;
63 };
64 using dice_iterator = content_iterator<DiceRef>;
65
66 /// ExportEntry encapsulates the current-state-of-the-walk used when doing a
67 /// non-recursive walk of the trie data structure. This allows you to iterate
68 /// across all exported symbols using:
69 /// Error Err = Error::success();
70 /// for (const llvm::object::ExportEntry &AnExport : Obj->exports(&Err)) {
71 /// }
72 /// if (Err) { report error ...
73 class ExportEntry {
74 public:
75 ExportEntry(Error *Err, const MachOObjectFile *O, ArrayRef<uint8_t> Trie);
76
77 StringRef name() const;
78 uint64_t flags() const;
79 uint64_t address() const;
80 uint64_t other() const;
81 StringRef otherName() const;
82 uint32_t nodeOffset() const;
83
84 bool operator==(const ExportEntry &) const;
85
86 void moveNext();
87
88 private:
89 friend class MachOObjectFile;
90
91 void moveToFirst();
92 void moveToEnd();
93 uint64_t readULEB128(const uint8_t *&p, const char **error);
94 void pushDownUntilBottom();
95 void pushNode(uint64_t Offset);
96
97 // Represents a node in the mach-o exports trie.
98 struct NodeState {
99 NodeState(const uint8_t *Ptr);
100
101 const uint8_t *Start;
102 const uint8_t *Current;
103 uint64_t Flags = 0;
104 uint64_t Address = 0;
105 uint64_t Other = 0;
106 const char *ImportName = nullptr;
107 unsigned ChildCount = 0;
108 unsigned NextChildIndex = 0;
109 unsigned ParentStringLength = 0;
110 bool IsExportNode = false;
111 };
112 using NodeList = SmallVector<NodeState, 16>;
113 using node_iterator = NodeList::const_iterator;
114
115 Error *E;
116 const MachOObjectFile *O;
117 ArrayRef<uint8_t> Trie;
118 SmallString<256> CumulativeString;
119 NodeList Stack;
120 bool Done = false;
121
nodes()122 iterator_range<node_iterator> nodes() const {
123 return make_range(Stack.begin(), Stack.end());
124 }
125 };
126 using export_iterator = content_iterator<ExportEntry>;
127
128 // Segment info so SegIndex/SegOffset pairs in a Mach-O Bind or Rebase entry
129 // can be checked and translated. Only the SegIndex/SegOffset pairs from
130 // checked entries are to be used with the segmentName(), sectionName() and
131 // address() methods below.
132 class BindRebaseSegInfo {
133 public:
134 BindRebaseSegInfo(const MachOObjectFile *Obj);
135
136 // Used to check a Mach-O Bind or Rebase entry for errors when iterating.
137 const char *checkSegAndOffsets(int32_t SegIndex, uint64_t SegOffset,
138 uint8_t PointerSize, uint64_t Count = 1,
139 uint64_t Skip = 0);
140 // Used with valid SegIndex/SegOffset values from checked entries.
141 StringRef segmentName(int32_t SegIndex);
142 StringRef sectionName(int32_t SegIndex, uint64_t SegOffset);
143 uint64_t address(uint32_t SegIndex, uint64_t SegOffset);
144
145 private:
146 struct SectionInfo {
147 uint64_t Address;
148 uint64_t Size;
149 StringRef SectionName;
150 StringRef SegmentName;
151 uint64_t OffsetInSegment;
152 uint64_t SegmentStartAddress;
153 int32_t SegmentIndex;
154 };
155 const SectionInfo &findSection(int32_t SegIndex, uint64_t SegOffset);
156
157 SmallVector<SectionInfo, 32> Sections;
158 int32_t MaxSegIndex;
159 };
160
161 /// MachORebaseEntry encapsulates the current state in the decompression of
162 /// rebasing opcodes. This allows you to iterate through the compressed table of
163 /// rebasing using:
164 /// Error Err = Error::success();
165 /// for (const llvm::object::MachORebaseEntry &Entry : Obj->rebaseTable(&Err)) {
166 /// }
167 /// if (Err) { report error ...
168 class MachORebaseEntry {
169 public:
170 MachORebaseEntry(Error *Err, const MachOObjectFile *O,
171 ArrayRef<uint8_t> opcodes, bool is64Bit);
172
173 int32_t segmentIndex() const;
174 uint64_t segmentOffset() const;
175 StringRef typeName() const;
176 StringRef segmentName() const;
177 StringRef sectionName() const;
178 uint64_t address() const;
179
180 bool operator==(const MachORebaseEntry &) const;
181
182 void moveNext();
183
184 private:
185 friend class MachOObjectFile;
186
187 void moveToFirst();
188 void moveToEnd();
189 uint64_t readULEB128(const char **error);
190
191 Error *E;
192 const MachOObjectFile *O;
193 ArrayRef<uint8_t> Opcodes;
194 const uint8_t *Ptr;
195 uint64_t SegmentOffset = 0;
196 int32_t SegmentIndex = -1;
197 uint64_t RemainingLoopCount = 0;
198 uint64_t AdvanceAmount = 0;
199 uint8_t RebaseType = 0;
200 uint8_t PointerSize;
201 bool Done = false;
202 };
203 using rebase_iterator = content_iterator<MachORebaseEntry>;
204
205 /// MachOBindEntry encapsulates the current state in the decompression of
206 /// binding opcodes. This allows you to iterate through the compressed table of
207 /// bindings using:
208 /// Error Err = Error::success();
209 /// for (const llvm::object::MachOBindEntry &Entry : Obj->bindTable(&Err)) {
210 /// }
211 /// if (Err) { report error ...
212 class MachOBindEntry {
213 public:
214 enum class Kind { Regular, Lazy, Weak };
215
216 MachOBindEntry(Error *Err, const MachOObjectFile *O,
217 ArrayRef<uint8_t> Opcodes, bool is64Bit, MachOBindEntry::Kind);
218
219 int32_t segmentIndex() const;
220 uint64_t segmentOffset() const;
221 StringRef typeName() const;
222 StringRef symbolName() const;
223 uint32_t flags() const;
224 int64_t addend() const;
225 int ordinal() const;
226
227 StringRef segmentName() const;
228 StringRef sectionName() const;
229 uint64_t address() const;
230
231 bool operator==(const MachOBindEntry &) const;
232
233 void moveNext();
234
235 private:
236 friend class MachOObjectFile;
237
238 void moveToFirst();
239 void moveToEnd();
240 uint64_t readULEB128(const char **error);
241 int64_t readSLEB128(const char **error);
242
243 Error *E;
244 const MachOObjectFile *O;
245 ArrayRef<uint8_t> Opcodes;
246 const uint8_t *Ptr;
247 uint64_t SegmentOffset = 0;
248 int32_t SegmentIndex = -1;
249 StringRef SymbolName;
250 bool LibraryOrdinalSet = false;
251 int Ordinal = 0;
252 uint32_t Flags = 0;
253 int64_t Addend = 0;
254 uint64_t RemainingLoopCount = 0;
255 uint64_t AdvanceAmount = 0;
256 uint8_t BindType = 0;
257 uint8_t PointerSize;
258 Kind TableKind;
259 bool Done = false;
260 };
261 using bind_iterator = content_iterator<MachOBindEntry>;
262
263 /// ChainedFixupTarget holds all the information about an external symbol
264 /// necessary to bind this binary to that symbol. These values are referenced
265 /// indirectly by chained fixup binds. This structure captures values from all
266 /// import and symbol formats.
267 ///
268 /// Be aware there are two notions of weak here:
269 /// WeakImport == true
270 /// The associated bind may be set to 0 if this symbol is missing from its
271 /// parent library. This is called a "weak import."
272 /// LibOrdinal == BIND_SPECIAL_DYLIB_WEAK_LOOKUP
273 /// This symbol may be coalesced with other libraries vending the same
274 /// symbol. E.g., C++'s "operator new". This is called a "weak bind."
275 struct ChainedFixupTarget {
276 public:
ChainedFixupTargetChainedFixupTarget277 ChainedFixupTarget(int LibOrdinal, uint32_t NameOffset, StringRef Symbol,
278 uint64_t Addend, bool WeakImport)
279 : LibOrdinal(LibOrdinal), NameOffset(NameOffset), SymbolName(Symbol),
280 Addend(Addend), WeakImport(WeakImport) {}
281
libOrdinalChainedFixupTarget282 int libOrdinal() { return LibOrdinal; }
nameOffsetChainedFixupTarget283 uint32_t nameOffset() { return NameOffset; }
symbolNameChainedFixupTarget284 StringRef symbolName() { return SymbolName; }
addendChainedFixupTarget285 uint64_t addend() { return Addend; }
weakImportChainedFixupTarget286 bool weakImport() { return WeakImport; }
weakBindChainedFixupTarget287 bool weakBind() {
288 return LibOrdinal == MachO::BIND_SPECIAL_DYLIB_WEAK_LOOKUP;
289 }
290
291 private:
292 int LibOrdinal;
293 uint32_t NameOffset;
294 StringRef SymbolName;
295 uint64_t Addend;
296 bool WeakImport;
297 };
298
299 struct ChainedFixupsSegment {
ChainedFixupsSegmentChainedFixupsSegment300 ChainedFixupsSegment(uint8_t SegIdx, uint32_t Offset,
301 const MachO::dyld_chained_starts_in_segment &Header,
302 std::vector<uint16_t> &&PageStarts)
303 : SegIdx(SegIdx), Offset(Offset), Header(Header),
304 PageStarts(PageStarts){};
305
306 uint32_t SegIdx;
307 uint32_t Offset; // dyld_chained_starts_in_image::seg_info_offset[SegIdx]
308 MachO::dyld_chained_starts_in_segment Header;
309 std::vector<uint16_t> PageStarts; // page_start[] entries, host endianness
310 };
311
312 /// MachOAbstractFixupEntry is an abstract class representing a fixup in a
313 /// MH_DYLDLINK file. Fixups generally represent rebases and binds. Binds also
314 /// subdivide into additional subtypes (weak, lazy, reexport).
315 ///
316 /// The two concrete subclasses of MachOAbstractFixupEntry are:
317 ///
318 /// MachORebaseBindEntry - for dyld opcode-based tables, including threaded-
319 /// rebase, where rebases are mixed in with other
320 /// bind opcodes.
321 /// MachOChainedFixupEntry - for pointer chains embedded in data pages.
322 class MachOAbstractFixupEntry {
323 public:
324 MachOAbstractFixupEntry(Error *Err, const MachOObjectFile *O);
325
326 int32_t segmentIndex() const;
327 uint64_t segmentOffset() const;
328 uint64_t segmentAddress() const;
329 StringRef segmentName() const;
330 StringRef sectionName() const;
331 StringRef typeName() const;
332 StringRef symbolName() const;
333 uint32_t flags() const;
334 int64_t addend() const;
335 int ordinal() const;
336
337 /// \return the location of this fixup as a VM Address. For the VM
338 /// Address this fixup is pointing to, use pointerValue().
339 uint64_t address() const;
340
341 /// \return the VM Address pointed to by this fixup. Use
342 /// pointerValue() to compare against other VM Addresses, such as
343 /// section addresses or segment vmaddrs.
pointerValue()344 uint64_t pointerValue() const { return PointerValue; }
345
346 /// \return the raw "on-disk" representation of the fixup. For
347 /// Threaded rebases and Chained pointers these values are generally
348 /// encoded into various different pointer formats. This value is
349 /// exposed in API for tools that want to display and annotate the
350 /// raw bits.
rawValue()351 uint64_t rawValue() const { return RawValue; }
352
353 void moveNext();
354
355 protected:
356 Error *E;
357 const MachOObjectFile *O;
358 uint64_t SegmentOffset = 0;
359 int32_t SegmentIndex = -1;
360 StringRef SymbolName;
361 int32_t Ordinal = 0;
362 uint32_t Flags = 0;
363 int64_t Addend = 0;
364 uint64_t PointerValue = 0;
365 uint64_t RawValue = 0;
366 bool Done = false;
367
368 void moveToFirst();
369 void moveToEnd();
370
371 /// \return the vm address of the start of __TEXT segment.
textAddress()372 uint64_t textAddress() const { return TextAddress; }
373
374 private:
375 uint64_t TextAddress;
376 };
377
378 class MachOChainedFixupEntry : public MachOAbstractFixupEntry {
379 public:
380 enum class FixupKind { Bind, Rebase };
381
382 MachOChainedFixupEntry(Error *Err, const MachOObjectFile *O, bool Parse);
383
384 bool operator==(const MachOChainedFixupEntry &) const;
385
isBind()386 bool isBind() const { return Kind == FixupKind::Bind; }
isRebase()387 bool isRebase() const { return Kind == FixupKind::Rebase; }
388
389 void moveNext();
390 void moveToFirst();
391 void moveToEnd();
392
393 private:
394 void findNextPageWithFixups();
395
396 std::vector<ChainedFixupTarget> FixupTargets;
397 std::vector<ChainedFixupsSegment> Segments;
398 ArrayRef<uint8_t> SegmentData;
399 FixupKind Kind;
400 uint32_t InfoSegIndex = 0; // Index into Segments
401 uint32_t PageIndex = 0; // Index into Segments[InfoSegIdx].PageStarts
402 uint32_t PageOffset = 0; // Page offset of the current fixup
403 };
404 using fixup_iterator = content_iterator<MachOChainedFixupEntry>;
405
406 class MachOObjectFile : public ObjectFile {
407 public:
408 struct LoadCommandInfo {
409 const char *Ptr; // Where in memory the load command is.
410 MachO::load_command C; // The command itself.
411 };
412 using LoadCommandList = SmallVector<LoadCommandInfo, 4>;
413 using load_command_iterator = LoadCommandList::const_iterator;
414
415 static Expected<std::unique_ptr<MachOObjectFile>>
416 create(MemoryBufferRef Object, bool IsLittleEndian, bool Is64Bits,
417 uint32_t UniversalCputype = 0, uint32_t UniversalIndex = 0,
418 size_t MachOFilesetEntryOffset = 0);
419
420 static bool isMachOPairedReloc(uint64_t RelocType, uint64_t Arch);
421
422 void moveSymbolNext(DataRefImpl &Symb) const override;
423
424 uint64_t getNValue(DataRefImpl Sym) const;
425 Expected<StringRef> getSymbolName(DataRefImpl Symb) const override;
426
427 // MachO specific.
428 Error checkSymbolTable() const;
429
430 std::error_code getIndirectName(DataRefImpl Symb, StringRef &Res) const;
431 unsigned getSectionType(SectionRef Sec) const;
432
433 Expected<uint64_t> getSymbolAddress(DataRefImpl Symb) const override;
434 uint32_t getSymbolAlignment(DataRefImpl Symb) const override;
435 uint64_t getCommonSymbolSizeImpl(DataRefImpl Symb) const override;
436 Expected<SymbolRef::Type> getSymbolType(DataRefImpl Symb) const override;
437 Expected<uint32_t> getSymbolFlags(DataRefImpl Symb) const override;
438 Expected<section_iterator> getSymbolSection(DataRefImpl Symb) const override;
439 unsigned getSymbolSectionID(SymbolRef Symb) const;
440 unsigned getSectionID(SectionRef Sec) const;
441
442 void moveSectionNext(DataRefImpl &Sec) const override;
443 Expected<StringRef> getSectionName(DataRefImpl Sec) const override;
444 uint64_t getSectionAddress(DataRefImpl Sec) const override;
445 uint64_t getSectionIndex(DataRefImpl Sec) const override;
446 uint64_t getSectionSize(DataRefImpl Sec) const override;
447 ArrayRef<uint8_t> getSectionContents(uint32_t Offset, uint64_t Size) const;
448 Expected<ArrayRef<uint8_t>>
449 getSectionContents(DataRefImpl Sec) const override;
450 uint64_t getSectionAlignment(DataRefImpl Sec) const override;
451 Expected<SectionRef> getSection(unsigned SectionIndex) const;
452 Expected<SectionRef> getSection(StringRef SectionName) const;
453 bool isSectionCompressed(DataRefImpl Sec) const override;
454 bool isSectionText(DataRefImpl Sec) const override;
455 bool isSectionData(DataRefImpl Sec) const override;
456 bool isSectionBSS(DataRefImpl Sec) const override;
457 bool isSectionVirtual(DataRefImpl Sec) const override;
458 bool isSectionBitcode(DataRefImpl Sec) const override;
459 bool isDebugSection(DataRefImpl Sec) const override;
460
461 /// Return the raw contents of an entire segment.
462 ArrayRef<uint8_t> getSegmentContents(StringRef SegmentName) const;
463 ArrayRef<uint8_t> getSegmentContents(size_t SegmentIndex) const;
464
465 /// When dsymutil generates the companion file, it strips all unnecessary
466 /// sections (e.g. everything in the _TEXT segment) by omitting their body
467 /// and setting the offset in their corresponding load command to zero.
468 ///
469 /// While the load command itself is valid, reading the section corresponds
470 /// to reading the number of bytes specified in the load command, starting
471 /// from offset 0 (i.e. the Mach-O header at the beginning of the file).
472 bool isSectionStripped(DataRefImpl Sec) const override;
473
474 relocation_iterator section_rel_begin(DataRefImpl Sec) const override;
475 relocation_iterator section_rel_end(DataRefImpl Sec) const override;
476
477 relocation_iterator extrel_begin() const;
478 relocation_iterator extrel_end() const;
external_relocations()479 iterator_range<relocation_iterator> external_relocations() const {
480 return make_range(extrel_begin(), extrel_end());
481 }
482
483 relocation_iterator locrel_begin() const;
484 relocation_iterator locrel_end() const;
485
486 void moveRelocationNext(DataRefImpl &Rel) const override;
487 uint64_t getRelocationOffset(DataRefImpl Rel) const override;
488 symbol_iterator getRelocationSymbol(DataRefImpl Rel) const override;
489 section_iterator getRelocationSection(DataRefImpl Rel) const;
490 uint64_t getRelocationType(DataRefImpl Rel) const override;
491 void getRelocationTypeName(DataRefImpl Rel,
492 SmallVectorImpl<char> &Result) const override;
493 uint8_t getRelocationLength(DataRefImpl Rel) const;
494
495 // MachO specific.
496 std::error_code getLibraryShortNameByIndex(unsigned Index, StringRef &) const;
497 uint32_t getLibraryCount() const;
498
499 section_iterator getRelocationRelocatedSection(relocation_iterator Rel) const;
500
501 // TODO: Would be useful to have an iterator based version
502 // of the load command interface too.
503
504 basic_symbol_iterator symbol_begin() const override;
505 basic_symbol_iterator symbol_end() const override;
506
507 bool is64Bit() const override;
508
509 // MachO specific.
510 symbol_iterator getSymbolByIndex(unsigned Index) const;
511 uint64_t getSymbolIndex(DataRefImpl Symb) const;
512
513 section_iterator section_begin() const override;
514 section_iterator section_end() const override;
515
516 uint8_t getBytesInAddress() const override;
517
518 StringRef getFileFormatName() const override;
519 Triple::ArchType getArch() const override;
getFeatures()520 Expected<SubtargetFeatures> getFeatures() const override {
521 return SubtargetFeatures();
522 }
523 Triple getArchTriple(const char **McpuDefault = nullptr) const;
524
525 relocation_iterator section_rel_begin(unsigned Index) const;
526 relocation_iterator section_rel_end(unsigned Index) const;
527
528 dice_iterator begin_dices() const;
529 dice_iterator end_dices() const;
530
531 load_command_iterator begin_load_commands() const;
532 load_command_iterator end_load_commands() const;
533 iterator_range<load_command_iterator> load_commands() const;
534
535 /// For use iterating over all exported symbols.
536 iterator_range<export_iterator> exports(Error &Err) const;
537
538 /// For use examining a trie not in a MachOObjectFile.
539 static iterator_range<export_iterator> exports(Error &Err,
540 ArrayRef<uint8_t> Trie,
541 const MachOObjectFile *O =
542 nullptr);
543
544 /// For use iterating over all rebase table entries.
545 iterator_range<rebase_iterator> rebaseTable(Error &Err);
546
547 /// For use examining rebase opcodes in a MachOObjectFile.
548 static iterator_range<rebase_iterator> rebaseTable(Error &Err,
549 MachOObjectFile *O,
550 ArrayRef<uint8_t> Opcodes,
551 bool is64);
552
553 /// For use iterating over all bind table entries.
554 iterator_range<bind_iterator> bindTable(Error &Err);
555
556 /// For iterating over all chained fixups.
557 iterator_range<fixup_iterator> fixupTable(Error &Err);
558
559 /// For use iterating over all lazy bind table entries.
560 iterator_range<bind_iterator> lazyBindTable(Error &Err);
561
562 /// For use iterating over all weak bind table entries.
563 iterator_range<bind_iterator> weakBindTable(Error &Err);
564
565 /// For use examining bind opcodes in a MachOObjectFile.
566 static iterator_range<bind_iterator> bindTable(Error &Err,
567 MachOObjectFile *O,
568 ArrayRef<uint8_t> Opcodes,
569 bool is64,
570 MachOBindEntry::Kind);
571
572 // Given a SegIndex, SegOffset, and PointerSize, verify a valid section exists
573 // that fully contains a pointer at that location. Multiple fixups in a bind
574 // (such as with the BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB opcode) can
575 // be tested via the Count and Skip parameters.
576 //
577 // This is used by MachOBindEntry::moveNext() to validate a MachOBindEntry.
578 const char *BindEntryCheckSegAndOffsets(int32_t SegIndex, uint64_t SegOffset,
579 uint8_t PointerSize,
580 uint64_t Count = 1,
581 uint64_t Skip = 0) const {
582 return BindRebaseSectionTable->checkSegAndOffsets(SegIndex, SegOffset,
583 PointerSize, Count, Skip);
584 }
585
586 // Given a SegIndex, SegOffset, and PointerSize, verify a valid section exists
587 // that fully contains a pointer at that location. Multiple fixups in a rebase
588 // (such as with the REBASE_OPCODE_DO_*_TIMES* opcodes) can be tested via the
589 // Count and Skip parameters.
590 //
591 // This is used by MachORebaseEntry::moveNext() to validate a MachORebaseEntry
592 const char *RebaseEntryCheckSegAndOffsets(int32_t SegIndex,
593 uint64_t SegOffset,
594 uint8_t PointerSize,
595 uint64_t Count = 1,
596 uint64_t Skip = 0) const {
597 return BindRebaseSectionTable->checkSegAndOffsets(SegIndex, SegOffset,
598 PointerSize, Count, Skip);
599 }
600
601 /// For use with the SegIndex of a checked Mach-O Bind or Rebase entry to
602 /// get the segment name.
BindRebaseSegmentName(int32_t SegIndex)603 StringRef BindRebaseSegmentName(int32_t SegIndex) const {
604 return BindRebaseSectionTable->segmentName(SegIndex);
605 }
606
607 /// For use with a SegIndex,SegOffset pair from a checked Mach-O Bind or
608 /// Rebase entry to get the section name.
BindRebaseSectionName(uint32_t SegIndex,uint64_t SegOffset)609 StringRef BindRebaseSectionName(uint32_t SegIndex, uint64_t SegOffset) const {
610 return BindRebaseSectionTable->sectionName(SegIndex, SegOffset);
611 }
612
613 /// For use with a SegIndex,SegOffset pair from a checked Mach-O Bind or
614 /// Rebase entry to get the address.
BindRebaseAddress(uint32_t SegIndex,uint64_t SegOffset)615 uint64_t BindRebaseAddress(uint32_t SegIndex, uint64_t SegOffset) const {
616 return BindRebaseSectionTable->address(SegIndex, SegOffset);
617 }
618
619 // In a MachO file, sections have a segment name. This is used in the .o
620 // files. They have a single segment, but this field specifies which segment
621 // a section should be put in the final object.
622 StringRef getSectionFinalSegmentName(DataRefImpl Sec) const;
623
624 // Names are stored as 16 bytes. These returns the raw 16 bytes without
625 // interpreting them as a C string.
626 ArrayRef<char> getSectionRawName(DataRefImpl Sec) const;
627 ArrayRef<char> getSectionRawFinalSegmentName(DataRefImpl Sec) const;
628
629 // MachO specific Info about relocations.
630 bool isRelocationScattered(const MachO::any_relocation_info &RE) const;
631 unsigned getPlainRelocationSymbolNum(
632 const MachO::any_relocation_info &RE) const;
633 bool getPlainRelocationExternal(const MachO::any_relocation_info &RE) const;
634 bool getScatteredRelocationScattered(
635 const MachO::any_relocation_info &RE) const;
636 uint32_t getScatteredRelocationValue(
637 const MachO::any_relocation_info &RE) const;
638 uint32_t getScatteredRelocationType(
639 const MachO::any_relocation_info &RE) const;
640 unsigned getAnyRelocationAddress(const MachO::any_relocation_info &RE) const;
641 unsigned getAnyRelocationPCRel(const MachO::any_relocation_info &RE) const;
642 unsigned getAnyRelocationLength(const MachO::any_relocation_info &RE) const;
643 unsigned getAnyRelocationType(const MachO::any_relocation_info &RE) const;
644 SectionRef getAnyRelocationSection(const MachO::any_relocation_info &RE) const;
645
646 // MachO specific structures.
647 MachO::section getSection(DataRefImpl DRI) const;
648 MachO::section_64 getSection64(DataRefImpl DRI) const;
649 MachO::section getSection(const LoadCommandInfo &L, unsigned Index) const;
650 MachO::section_64 getSection64(const LoadCommandInfo &L,unsigned Index) const;
651 MachO::nlist getSymbolTableEntry(DataRefImpl DRI) const;
652 MachO::nlist_64 getSymbol64TableEntry(DataRefImpl DRI) const;
653
654 MachO::linkedit_data_command
655 getLinkeditDataLoadCommand(const LoadCommandInfo &L) const;
656 MachO::segment_command
657 getSegmentLoadCommand(const LoadCommandInfo &L) const;
658 MachO::segment_command_64
659 getSegment64LoadCommand(const LoadCommandInfo &L) const;
660 MachO::linker_option_command
661 getLinkerOptionLoadCommand(const LoadCommandInfo &L) const;
662 MachO::version_min_command
663 getVersionMinLoadCommand(const LoadCommandInfo &L) const;
664 MachO::note_command
665 getNoteLoadCommand(const LoadCommandInfo &L) const;
666 MachO::build_version_command
667 getBuildVersionLoadCommand(const LoadCommandInfo &L) const;
668 MachO::build_tool_version
669 getBuildToolVersion(unsigned index) const;
670 MachO::dylib_command
671 getDylibIDLoadCommand(const LoadCommandInfo &L) const;
672 MachO::dyld_info_command
673 getDyldInfoLoadCommand(const LoadCommandInfo &L) const;
674 MachO::dylinker_command
675 getDylinkerCommand(const LoadCommandInfo &L) const;
676 MachO::uuid_command
677 getUuidCommand(const LoadCommandInfo &L) const;
678 MachO::rpath_command
679 getRpathCommand(const LoadCommandInfo &L) const;
680 MachO::source_version_command
681 getSourceVersionCommand(const LoadCommandInfo &L) const;
682 MachO::entry_point_command
683 getEntryPointCommand(const LoadCommandInfo &L) const;
684 MachO::encryption_info_command
685 getEncryptionInfoCommand(const LoadCommandInfo &L) const;
686 MachO::encryption_info_command_64
687 getEncryptionInfoCommand64(const LoadCommandInfo &L) const;
688 MachO::sub_framework_command
689 getSubFrameworkCommand(const LoadCommandInfo &L) const;
690 MachO::sub_umbrella_command
691 getSubUmbrellaCommand(const LoadCommandInfo &L) const;
692 MachO::sub_library_command
693 getSubLibraryCommand(const LoadCommandInfo &L) const;
694 MachO::sub_client_command
695 getSubClientCommand(const LoadCommandInfo &L) const;
696 MachO::routines_command
697 getRoutinesCommand(const LoadCommandInfo &L) const;
698 MachO::routines_command_64
699 getRoutinesCommand64(const LoadCommandInfo &L) const;
700 MachO::thread_command
701 getThreadCommand(const LoadCommandInfo &L) const;
702 MachO::fileset_entry_command
703 getFilesetEntryLoadCommand(const LoadCommandInfo &L) const;
704
705 MachO::any_relocation_info getRelocation(DataRefImpl Rel) const;
706 MachO::data_in_code_entry getDice(DataRefImpl Rel) const;
707 const MachO::mach_header &getHeader() const;
708 const MachO::mach_header_64 &getHeader64() const;
709 uint32_t
710 getIndirectSymbolTableEntry(const MachO::dysymtab_command &DLC,
711 unsigned Index) const;
712 MachO::data_in_code_entry getDataInCodeTableEntry(uint32_t DataOffset,
713 unsigned Index) const;
714 MachO::symtab_command getSymtabLoadCommand() const;
715 MachO::dysymtab_command getDysymtabLoadCommand() const;
716 MachO::linkedit_data_command getDataInCodeLoadCommand() const;
717 MachO::linkedit_data_command getLinkOptHintsLoadCommand() const;
718 ArrayRef<uint8_t> getDyldInfoRebaseOpcodes() const;
719 ArrayRef<uint8_t> getDyldInfoBindOpcodes() const;
720 ArrayRef<uint8_t> getDyldInfoWeakBindOpcodes() const;
721 ArrayRef<uint8_t> getDyldInfoLazyBindOpcodes() const;
722 ArrayRef<uint8_t> getDyldInfoExportsTrie() const;
723
724 /// If the optional is std::nullopt, no header was found, but the object was
725 /// well-formed.
726 Expected<std::optional<MachO::dyld_chained_fixups_header>>
727 getChainedFixupsHeader() const;
728 Expected<std::vector<ChainedFixupTarget>> getDyldChainedFixupTargets() const;
729
730 // Note: This is a limited, temporary API, which will be removed when Apple
731 // upstreams their implementation. Please do not rely on this.
732 Expected<std::optional<MachO::linkedit_data_command>>
733 getChainedFixupsLoadCommand() const;
734 // Returns the number of sections listed in dyld_chained_starts_in_image, and
735 // a ChainedFixupsSegment for each segment that has fixups.
736 Expected<std::pair<size_t, std::vector<ChainedFixupsSegment>>>
737 getChainedFixupsSegments() const;
738 ArrayRef<uint8_t> getDyldExportsTrie() const;
739
740 SmallVector<uint64_t> getFunctionStarts() const;
741 ArrayRef<uint8_t> getUuid() const;
742
743 StringRef getStringTableData() const;
744
745 void ReadULEB128s(uint64_t Index, SmallVectorImpl<uint64_t> &Out) const;
746
747 static StringRef guessLibraryShortName(StringRef Name, bool &isFramework,
748 StringRef &Suffix);
749
750 static Triple::ArchType getArch(uint32_t CPUType, uint32_t CPUSubType);
751 static Triple getArchTriple(uint32_t CPUType, uint32_t CPUSubType,
752 const char **McpuDefault = nullptr,
753 const char **ArchFlag = nullptr);
754 static bool isValidArch(StringRef ArchFlag);
755 static ArrayRef<StringRef> getValidArchs();
756 static Triple getHostArch();
757
758 bool isRelocatableObject() const override;
759
760 StringRef mapDebugSectionName(StringRef Name) const override;
761
762 llvm::binaryformat::Swift5ReflectionSectionKind
763 mapReflectionSectionNameToEnumValue(StringRef SectionName) const override;
764
hasPageZeroSegment()765 bool hasPageZeroSegment() const { return HasPageZeroSegment; }
766
getMachOFilesetEntryOffset()767 size_t getMachOFilesetEntryOffset() const { return MachOFilesetEntryOffset; }
768
classof(const Binary * v)769 static bool classof(const Binary *v) {
770 return v->isMachO();
771 }
772
773 static uint32_t
getVersionMinMajor(MachO::version_min_command & C,bool SDK)774 getVersionMinMajor(MachO::version_min_command &C, bool SDK) {
775 uint32_t VersionOrSDK = (SDK) ? C.sdk : C.version;
776 return (VersionOrSDK >> 16) & 0xffff;
777 }
778
779 static uint32_t
getVersionMinMinor(MachO::version_min_command & C,bool SDK)780 getVersionMinMinor(MachO::version_min_command &C, bool SDK) {
781 uint32_t VersionOrSDK = (SDK) ? C.sdk : C.version;
782 return (VersionOrSDK >> 8) & 0xff;
783 }
784
785 static uint32_t
getVersionMinUpdate(MachO::version_min_command & C,bool SDK)786 getVersionMinUpdate(MachO::version_min_command &C, bool SDK) {
787 uint32_t VersionOrSDK = (SDK) ? C.sdk : C.version;
788 return VersionOrSDK & 0xff;
789 }
790
getBuildPlatform(uint32_t platform)791 static std::string getBuildPlatform(uint32_t platform) {
792 switch (platform) {
793 #define PLATFORM(platform, id, name, build_name, target, tapi_target, \
794 marketing) \
795 case MachO::PLATFORM_##platform: \
796 return #name;
797 #include "llvm/BinaryFormat/MachO.def"
798 default:
799 std::string ret;
800 raw_string_ostream ss(ret);
801 ss << format_hex(platform, 8, true);
802 return ret;
803 }
804 }
805
getBuildTool(uint32_t tools)806 static std::string getBuildTool(uint32_t tools) {
807 switch (tools) {
808 case MachO::TOOL_CLANG: return "clang";
809 case MachO::TOOL_SWIFT: return "swift";
810 case MachO::TOOL_LD: return "ld";
811 case MachO::TOOL_LLD:
812 return "lld";
813 default:
814 std::string ret;
815 raw_string_ostream ss(ret);
816 ss << format_hex(tools, 8, true);
817 return ret;
818 }
819 }
820
getVersionString(uint32_t version)821 static std::string getVersionString(uint32_t version) {
822 uint32_t major = (version >> 16) & 0xffff;
823 uint32_t minor = (version >> 8) & 0xff;
824 uint32_t update = version & 0xff;
825
826 SmallString<32> Version;
827 Version = utostr(major) + "." + utostr(minor);
828 if (update != 0)
829 Version += "." + utostr(update);
830 return std::string(std::string(Version));
831 }
832
833 /// If the input path is a .dSYM bundle (as created by the dsymutil tool),
834 /// return the paths to the object files found in the bundle, otherwise return
835 /// an empty vector. If the path appears to be a .dSYM bundle but no objects
836 /// were found or there was a filesystem error, then return an error.
837 static Expected<std::vector<std::string>>
838 findDsymObjectMembers(StringRef Path);
839
840 private:
841 MachOObjectFile(MemoryBufferRef Object, bool IsLittleEndian, bool Is64Bits,
842 Error &Err, uint32_t UniversalCputype = 0,
843 uint32_t UniversalIndex = 0,
844 size_t MachOFilesetEntryOffset = 0);
845
846 uint64_t getSymbolValueImpl(DataRefImpl Symb) const override;
847
848 union {
849 MachO::mach_header_64 Header64;
850 MachO::mach_header Header;
851 };
852 using SectionList = SmallVector<const char*, 1>;
853 SectionList Sections;
854 using LibraryList = SmallVector<const char*, 1>;
855 LibraryList Libraries;
856 LoadCommandList LoadCommands;
857 using LibraryShortName = SmallVector<StringRef, 1>;
858 using BuildToolList = SmallVector<const char*, 1>;
859 BuildToolList BuildTools;
860 mutable LibraryShortName LibrariesShortNames;
861 std::unique_ptr<BindRebaseSegInfo> BindRebaseSectionTable;
862 const char *SymtabLoadCmd = nullptr;
863 const char *DysymtabLoadCmd = nullptr;
864 const char *DataInCodeLoadCmd = nullptr;
865 const char *LinkOptHintsLoadCmd = nullptr;
866 const char *DyldInfoLoadCmd = nullptr;
867 const char *FuncStartsLoadCmd = nullptr;
868 const char *DyldChainedFixupsLoadCmd = nullptr;
869 const char *DyldExportsTrieLoadCmd = nullptr;
870 const char *UuidLoadCmd = nullptr;
871 bool HasPageZeroSegment = false;
872 size_t MachOFilesetEntryOffset = 0;
873 };
874
875 /// DiceRef
DiceRef(DataRefImpl DiceP,const ObjectFile * Owner)876 inline DiceRef::DiceRef(DataRefImpl DiceP, const ObjectFile *Owner)
877 : DicePimpl(DiceP) , OwningObject(Owner) {}
878
879 inline bool DiceRef::operator==(const DiceRef &Other) const {
880 return DicePimpl == Other.DicePimpl;
881 }
882
883 inline bool DiceRef::operator<(const DiceRef &Other) const {
884 return DicePimpl < Other.DicePimpl;
885 }
886
moveNext()887 inline void DiceRef::moveNext() {
888 const MachO::data_in_code_entry *P =
889 reinterpret_cast<const MachO::data_in_code_entry *>(DicePimpl.p);
890 DicePimpl.p = reinterpret_cast<uintptr_t>(P + 1);
891 }
892
893 // Since a Mach-O data in code reference, a DiceRef, can only be created when
894 // the OwningObject ObjectFile is a MachOObjectFile a static_cast<> is used for
895 // the methods that get the values of the fields of the reference.
896
getOffset(uint32_t & Result)897 inline std::error_code DiceRef::getOffset(uint32_t &Result) const {
898 const MachOObjectFile *MachOOF =
899 static_cast<const MachOObjectFile *>(OwningObject);
900 MachO::data_in_code_entry Dice = MachOOF->getDice(DicePimpl);
901 Result = Dice.offset;
902 return std::error_code();
903 }
904
getLength(uint16_t & Result)905 inline std::error_code DiceRef::getLength(uint16_t &Result) const {
906 const MachOObjectFile *MachOOF =
907 static_cast<const MachOObjectFile *>(OwningObject);
908 MachO::data_in_code_entry Dice = MachOOF->getDice(DicePimpl);
909 Result = Dice.length;
910 return std::error_code();
911 }
912
getKind(uint16_t & Result)913 inline std::error_code DiceRef::getKind(uint16_t &Result) const {
914 const MachOObjectFile *MachOOF =
915 static_cast<const MachOObjectFile *>(OwningObject);
916 MachO::data_in_code_entry Dice = MachOOF->getDice(DicePimpl);
917 Result = Dice.kind;
918 return std::error_code();
919 }
920
getRawDataRefImpl()921 inline DataRefImpl DiceRef::getRawDataRefImpl() const {
922 return DicePimpl;
923 }
924
getObjectFile()925 inline const ObjectFile *DiceRef::getObjectFile() const {
926 return OwningObject;
927 }
928
929 } // end namespace object
930 } // end namespace llvm
931
932 #endif // LLVM_OBJECT_MACHO_H
933