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/Triple.h" 23 #include "llvm/ADT/iterator_range.h" 24 #include "llvm/BinaryFormat/MachO.h" 25 #include "llvm/BinaryFormat/Swift.h" 26 #include "llvm/MC/SubtargetFeature.h" 27 #include "llvm/Object/Binary.h" 28 #include "llvm/Object/ObjectFile.h" 29 #include "llvm/Object/SymbolicFile.h" 30 #include "llvm/Support/Error.h" 31 #include "llvm/Support/Format.h" 32 #include "llvm/Support/MemoryBuffer.h" 33 #include "llvm/Support/raw_ostream.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; 121 122 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, uint32_t Count=1, 139 uint32_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: 277 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) {} 281 282 int libOrdinal() { return LibOrdinal; } 283 uint32_t nameOffset() { return NameOffset; } 284 StringRef symbolName() { return SymbolName; } 285 uint64_t addend() { return Addend; } 286 bool weakImport() { return WeakImport; } 287 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 { 300 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. 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. 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. 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; 385 386 bool isBind() const { return Kind == FixupKind::Bind; } 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); 418 419 static bool isMachOPairedReloc(uint64_t RelocType, uint64_t Arch); 420 421 void moveSymbolNext(DataRefImpl &Symb) const override; 422 423 uint64_t getNValue(DataRefImpl Sym) const; 424 Expected<StringRef> getSymbolName(DataRefImpl Symb) const override; 425 426 // MachO specific. 427 Error checkSymbolTable() const; 428 429 std::error_code getIndirectName(DataRefImpl Symb, StringRef &Res) const; 430 unsigned getSectionType(SectionRef Sec) const; 431 432 Expected<uint64_t> getSymbolAddress(DataRefImpl Symb) const override; 433 uint32_t getSymbolAlignment(DataRefImpl Symb) const override; 434 uint64_t getCommonSymbolSizeImpl(DataRefImpl Symb) const override; 435 Expected<SymbolRef::Type> getSymbolType(DataRefImpl Symb) const override; 436 Expected<uint32_t> getSymbolFlags(DataRefImpl Symb) const override; 437 Expected<section_iterator> getSymbolSection(DataRefImpl Symb) const override; 438 unsigned getSymbolSectionID(SymbolRef Symb) const; 439 unsigned getSectionID(SectionRef Sec) const; 440 441 void moveSectionNext(DataRefImpl &Sec) const override; 442 Expected<StringRef> getSectionName(DataRefImpl Sec) const override; 443 uint64_t getSectionAddress(DataRefImpl Sec) const override; 444 uint64_t getSectionIndex(DataRefImpl Sec) const override; 445 uint64_t getSectionSize(DataRefImpl Sec) const override; 446 ArrayRef<uint8_t> getSectionContents(uint32_t Offset, uint64_t Size) const; 447 Expected<ArrayRef<uint8_t>> 448 getSectionContents(DataRefImpl Sec) const override; 449 uint64_t getSectionAlignment(DataRefImpl Sec) const override; 450 Expected<SectionRef> getSection(unsigned SectionIndex) const; 451 Expected<SectionRef> getSection(StringRef SectionName) const; 452 bool isSectionCompressed(DataRefImpl Sec) const override; 453 bool isSectionText(DataRefImpl Sec) const override; 454 bool isSectionData(DataRefImpl Sec) const override; 455 bool isSectionBSS(DataRefImpl Sec) const override; 456 bool isSectionVirtual(DataRefImpl Sec) const override; 457 bool isSectionBitcode(DataRefImpl Sec) const override; 458 bool isDebugSection(DataRefImpl Sec) const override; 459 460 /// Return the raw contents of an entire segment. 461 ArrayRef<uint8_t> getSegmentContents(StringRef SegmentName) const; 462 ArrayRef<uint8_t> getSegmentContents(size_t SegmentIndex) const; 463 464 /// When dsymutil generates the companion file, it strips all unnecessary 465 /// sections (e.g. everything in the _TEXT segment) by omitting their body 466 /// and setting the offset in their corresponding load command to zero. 467 /// 468 /// While the load command itself is valid, reading the section corresponds 469 /// to reading the number of bytes specified in the load command, starting 470 /// from offset 0 (i.e. the Mach-O header at the beginning of the file). 471 bool isSectionStripped(DataRefImpl Sec) const override; 472 473 relocation_iterator section_rel_begin(DataRefImpl Sec) const override; 474 relocation_iterator section_rel_end(DataRefImpl Sec) const override; 475 476 relocation_iterator extrel_begin() const; 477 relocation_iterator extrel_end() const; 478 iterator_range<relocation_iterator> external_relocations() const { 479 return make_range(extrel_begin(), extrel_end()); 480 } 481 482 relocation_iterator locrel_begin() const; 483 relocation_iterator locrel_end() const; 484 485 void moveRelocationNext(DataRefImpl &Rel) const override; 486 uint64_t getRelocationOffset(DataRefImpl Rel) const override; 487 symbol_iterator getRelocationSymbol(DataRefImpl Rel) const override; 488 section_iterator getRelocationSection(DataRefImpl Rel) const; 489 uint64_t getRelocationType(DataRefImpl Rel) const override; 490 void getRelocationTypeName(DataRefImpl Rel, 491 SmallVectorImpl<char> &Result) const override; 492 uint8_t getRelocationLength(DataRefImpl Rel) const; 493 494 // MachO specific. 495 std::error_code getLibraryShortNameByIndex(unsigned Index, StringRef &) const; 496 uint32_t getLibraryCount() const; 497 498 section_iterator getRelocationRelocatedSection(relocation_iterator Rel) const; 499 500 // TODO: Would be useful to have an iterator based version 501 // of the load command interface too. 502 503 basic_symbol_iterator symbol_begin() const override; 504 basic_symbol_iterator symbol_end() const override; 505 506 // MachO specific. 507 symbol_iterator getSymbolByIndex(unsigned Index) const; 508 uint64_t getSymbolIndex(DataRefImpl Symb) const; 509 510 section_iterator section_begin() const override; 511 section_iterator section_end() const override; 512 513 uint8_t getBytesInAddress() const override; 514 515 StringRef getFileFormatName() const override; 516 Triple::ArchType getArch() const override; 517 Expected<SubtargetFeatures> getFeatures() const override { 518 return SubtargetFeatures(); 519 } 520 Triple getArchTriple(const char **McpuDefault = nullptr) const; 521 522 relocation_iterator section_rel_begin(unsigned Index) const; 523 relocation_iterator section_rel_end(unsigned Index) const; 524 525 dice_iterator begin_dices() const; 526 dice_iterator end_dices() const; 527 528 load_command_iterator begin_load_commands() const; 529 load_command_iterator end_load_commands() const; 530 iterator_range<load_command_iterator> load_commands() const; 531 532 /// For use iterating over all exported symbols. 533 iterator_range<export_iterator> exports(Error &Err) const; 534 535 /// For use examining a trie not in a MachOObjectFile. 536 static iterator_range<export_iterator> exports(Error &Err, 537 ArrayRef<uint8_t> Trie, 538 const MachOObjectFile *O = 539 nullptr); 540 541 /// For use iterating over all rebase table entries. 542 iterator_range<rebase_iterator> rebaseTable(Error &Err); 543 544 /// For use examining rebase opcodes in a MachOObjectFile. 545 static iterator_range<rebase_iterator> rebaseTable(Error &Err, 546 MachOObjectFile *O, 547 ArrayRef<uint8_t> Opcodes, 548 bool is64); 549 550 /// For use iterating over all bind table entries. 551 iterator_range<bind_iterator> bindTable(Error &Err); 552 553 /// For iterating over all chained fixups. 554 iterator_range<fixup_iterator> fixupTable(Error &Err); 555 556 /// For use iterating over all lazy bind table entries. 557 iterator_range<bind_iterator> lazyBindTable(Error &Err); 558 559 /// For use iterating over all weak bind table entries. 560 iterator_range<bind_iterator> weakBindTable(Error &Err); 561 562 /// For use examining bind opcodes in a MachOObjectFile. 563 static iterator_range<bind_iterator> bindTable(Error &Err, 564 MachOObjectFile *O, 565 ArrayRef<uint8_t> Opcodes, 566 bool is64, 567 MachOBindEntry::Kind); 568 569 // Given a SegIndex, SegOffset, and PointerSize, verify a valid section exists 570 // that fully contains a pointer at that location. Multiple fixups in a bind 571 // (such as with the BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB opcode) can 572 // be tested via the Count and Skip parameters. 573 // 574 // This is used by MachOBindEntry::moveNext() to validate a MachOBindEntry. 575 const char *BindEntryCheckSegAndOffsets(int32_t SegIndex, uint64_t SegOffset, 576 uint8_t PointerSize, uint32_t Count=1, 577 uint32_t Skip=0) const { 578 return BindRebaseSectionTable->checkSegAndOffsets(SegIndex, SegOffset, 579 PointerSize, Count, Skip); 580 } 581 582 // Given a SegIndex, SegOffset, and PointerSize, verify a valid section exists 583 // that fully contains a pointer at that location. Multiple fixups in a rebase 584 // (such as with the REBASE_OPCODE_DO_*_TIMES* opcodes) can be tested via the 585 // Count and Skip parameters. 586 // 587 // This is used by MachORebaseEntry::moveNext() to validate a MachORebaseEntry 588 const char *RebaseEntryCheckSegAndOffsets(int32_t SegIndex, 589 uint64_t SegOffset, 590 uint8_t PointerSize, 591 uint32_t Count=1, 592 uint32_t Skip=0) const { 593 return BindRebaseSectionTable->checkSegAndOffsets(SegIndex, SegOffset, 594 PointerSize, Count, Skip); 595 } 596 597 /// For use with the SegIndex of a checked Mach-O Bind or Rebase entry to 598 /// get the segment name. 599 StringRef BindRebaseSegmentName(int32_t SegIndex) const { 600 return BindRebaseSectionTable->segmentName(SegIndex); 601 } 602 603 /// For use with a SegIndex,SegOffset pair from a checked Mach-O Bind or 604 /// Rebase entry to get the section name. 605 StringRef BindRebaseSectionName(uint32_t SegIndex, uint64_t SegOffset) const { 606 return BindRebaseSectionTable->sectionName(SegIndex, SegOffset); 607 } 608 609 /// For use with a SegIndex,SegOffset pair from a checked Mach-O Bind or 610 /// Rebase entry to get the address. 611 uint64_t BindRebaseAddress(uint32_t SegIndex, uint64_t SegOffset) const { 612 return BindRebaseSectionTable->address(SegIndex, SegOffset); 613 } 614 615 // In a MachO file, sections have a segment name. This is used in the .o 616 // files. They have a single segment, but this field specifies which segment 617 // a section should be put in the final object. 618 StringRef getSectionFinalSegmentName(DataRefImpl Sec) const; 619 620 // Names are stored as 16 bytes. These returns the raw 16 bytes without 621 // interpreting them as a C string. 622 ArrayRef<char> getSectionRawName(DataRefImpl Sec) const; 623 ArrayRef<char> getSectionRawFinalSegmentName(DataRefImpl Sec) const; 624 625 // MachO specific Info about relocations. 626 bool isRelocationScattered(const MachO::any_relocation_info &RE) const; 627 unsigned getPlainRelocationSymbolNum( 628 const MachO::any_relocation_info &RE) const; 629 bool getPlainRelocationExternal(const MachO::any_relocation_info &RE) const; 630 bool getScatteredRelocationScattered( 631 const MachO::any_relocation_info &RE) const; 632 uint32_t getScatteredRelocationValue( 633 const MachO::any_relocation_info &RE) const; 634 uint32_t getScatteredRelocationType( 635 const MachO::any_relocation_info &RE) const; 636 unsigned getAnyRelocationAddress(const MachO::any_relocation_info &RE) const; 637 unsigned getAnyRelocationPCRel(const MachO::any_relocation_info &RE) const; 638 unsigned getAnyRelocationLength(const MachO::any_relocation_info &RE) const; 639 unsigned getAnyRelocationType(const MachO::any_relocation_info &RE) const; 640 SectionRef getAnyRelocationSection(const MachO::any_relocation_info &RE) const; 641 642 // MachO specific structures. 643 MachO::section getSection(DataRefImpl DRI) const; 644 MachO::section_64 getSection64(DataRefImpl DRI) const; 645 MachO::section getSection(const LoadCommandInfo &L, unsigned Index) const; 646 MachO::section_64 getSection64(const LoadCommandInfo &L,unsigned Index) const; 647 MachO::nlist getSymbolTableEntry(DataRefImpl DRI) const; 648 MachO::nlist_64 getSymbol64TableEntry(DataRefImpl DRI) const; 649 650 MachO::linkedit_data_command 651 getLinkeditDataLoadCommand(const LoadCommandInfo &L) const; 652 MachO::segment_command 653 getSegmentLoadCommand(const LoadCommandInfo &L) const; 654 MachO::segment_command_64 655 getSegment64LoadCommand(const LoadCommandInfo &L) const; 656 MachO::linker_option_command 657 getLinkerOptionLoadCommand(const LoadCommandInfo &L) const; 658 MachO::version_min_command 659 getVersionMinLoadCommand(const LoadCommandInfo &L) const; 660 MachO::note_command 661 getNoteLoadCommand(const LoadCommandInfo &L) const; 662 MachO::build_version_command 663 getBuildVersionLoadCommand(const LoadCommandInfo &L) const; 664 MachO::build_tool_version 665 getBuildToolVersion(unsigned index) const; 666 MachO::dylib_command 667 getDylibIDLoadCommand(const LoadCommandInfo &L) const; 668 MachO::dyld_info_command 669 getDyldInfoLoadCommand(const LoadCommandInfo &L) const; 670 MachO::dylinker_command 671 getDylinkerCommand(const LoadCommandInfo &L) const; 672 MachO::uuid_command 673 getUuidCommand(const LoadCommandInfo &L) const; 674 MachO::rpath_command 675 getRpathCommand(const LoadCommandInfo &L) const; 676 MachO::source_version_command 677 getSourceVersionCommand(const LoadCommandInfo &L) const; 678 MachO::entry_point_command 679 getEntryPointCommand(const LoadCommandInfo &L) const; 680 MachO::encryption_info_command 681 getEncryptionInfoCommand(const LoadCommandInfo &L) const; 682 MachO::encryption_info_command_64 683 getEncryptionInfoCommand64(const LoadCommandInfo &L) const; 684 MachO::sub_framework_command 685 getSubFrameworkCommand(const LoadCommandInfo &L) const; 686 MachO::sub_umbrella_command 687 getSubUmbrellaCommand(const LoadCommandInfo &L) const; 688 MachO::sub_library_command 689 getSubLibraryCommand(const LoadCommandInfo &L) const; 690 MachO::sub_client_command 691 getSubClientCommand(const LoadCommandInfo &L) const; 692 MachO::routines_command 693 getRoutinesCommand(const LoadCommandInfo &L) const; 694 MachO::routines_command_64 695 getRoutinesCommand64(const LoadCommandInfo &L) const; 696 MachO::thread_command 697 getThreadCommand(const LoadCommandInfo &L) const; 698 699 MachO::any_relocation_info getRelocation(DataRefImpl Rel) const; 700 MachO::data_in_code_entry getDice(DataRefImpl Rel) const; 701 const MachO::mach_header &getHeader() const; 702 const MachO::mach_header_64 &getHeader64() const; 703 uint32_t 704 getIndirectSymbolTableEntry(const MachO::dysymtab_command &DLC, 705 unsigned Index) const; 706 MachO::data_in_code_entry getDataInCodeTableEntry(uint32_t DataOffset, 707 unsigned Index) const; 708 MachO::symtab_command getSymtabLoadCommand() const; 709 MachO::dysymtab_command getDysymtabLoadCommand() const; 710 MachO::linkedit_data_command getDataInCodeLoadCommand() const; 711 MachO::linkedit_data_command getLinkOptHintsLoadCommand() const; 712 ArrayRef<uint8_t> getDyldInfoRebaseOpcodes() const; 713 ArrayRef<uint8_t> getDyldInfoBindOpcodes() const; 714 ArrayRef<uint8_t> getDyldInfoWeakBindOpcodes() const; 715 ArrayRef<uint8_t> getDyldInfoLazyBindOpcodes() const; 716 ArrayRef<uint8_t> getDyldInfoExportsTrie() const; 717 718 /// If the optional is None, no header was found, but the object was 719 /// well-formed. 720 Expected<std::optional<MachO::dyld_chained_fixups_header>> 721 getChainedFixupsHeader() const; 722 Expected<std::vector<ChainedFixupTarget>> getDyldChainedFixupTargets() const; 723 724 // Note: This is a limited, temporary API, which will be removed when Apple 725 // upstreams their implementation. Please do not rely on this. 726 Expected<std::optional<MachO::linkedit_data_command>> 727 getChainedFixupsLoadCommand() const; 728 // Returns the number of sections listed in dyld_chained_starts_in_image, and 729 // a ChainedFixupsSegment for each segment that has fixups. 730 Expected<std::pair<size_t, std::vector<ChainedFixupsSegment>>> 731 getChainedFixupsSegments() const; 732 ArrayRef<uint8_t> getDyldExportsTrie() const; 733 734 SmallVector<uint64_t> getFunctionStarts() const; 735 ArrayRef<uint8_t> getUuid() const; 736 737 StringRef getStringTableData() const; 738 bool is64Bit() const; 739 void ReadULEB128s(uint64_t Index, SmallVectorImpl<uint64_t> &Out) const; 740 741 static StringRef guessLibraryShortName(StringRef Name, bool &isFramework, 742 StringRef &Suffix); 743 744 static Triple::ArchType getArch(uint32_t CPUType, uint32_t CPUSubType); 745 static Triple getArchTriple(uint32_t CPUType, uint32_t CPUSubType, 746 const char **McpuDefault = nullptr, 747 const char **ArchFlag = nullptr); 748 static bool isValidArch(StringRef ArchFlag); 749 static ArrayRef<StringRef> getValidArchs(); 750 static Triple getHostArch(); 751 752 bool isRelocatableObject() const override; 753 754 StringRef mapDebugSectionName(StringRef Name) const override; 755 756 llvm::binaryformat::Swift5ReflectionSectionKind 757 mapReflectionSectionNameToEnumValue(StringRef SectionName) const override; 758 759 bool hasPageZeroSegment() const { return HasPageZeroSegment; } 760 761 static bool classof(const Binary *v) { 762 return v->isMachO(); 763 } 764 765 static uint32_t 766 getVersionMinMajor(MachO::version_min_command &C, bool SDK) { 767 uint32_t VersionOrSDK = (SDK) ? C.sdk : C.version; 768 return (VersionOrSDK >> 16) & 0xffff; 769 } 770 771 static uint32_t 772 getVersionMinMinor(MachO::version_min_command &C, bool SDK) { 773 uint32_t VersionOrSDK = (SDK) ? C.sdk : C.version; 774 return (VersionOrSDK >> 8) & 0xff; 775 } 776 777 static uint32_t 778 getVersionMinUpdate(MachO::version_min_command &C, bool SDK) { 779 uint32_t VersionOrSDK = (SDK) ? C.sdk : C.version; 780 return VersionOrSDK & 0xff; 781 } 782 783 static std::string getBuildPlatform(uint32_t platform) { 784 switch (platform) { 785 case MachO::PLATFORM_MACOS: return "macos"; 786 case MachO::PLATFORM_IOS: return "ios"; 787 case MachO::PLATFORM_TVOS: return "tvos"; 788 case MachO::PLATFORM_WATCHOS: return "watchos"; 789 case MachO::PLATFORM_BRIDGEOS: return "bridgeos"; 790 case MachO::PLATFORM_MACCATALYST: return "macCatalyst"; 791 case MachO::PLATFORM_IOSSIMULATOR: return "iossimulator"; 792 case MachO::PLATFORM_TVOSSIMULATOR: return "tvossimulator"; 793 case MachO::PLATFORM_WATCHOSSIMULATOR: return "watchossimulator"; 794 case MachO::PLATFORM_DRIVERKIT: return "driverkit"; 795 default: 796 std::string ret; 797 raw_string_ostream ss(ret); 798 ss << format_hex(platform, 8, true); 799 return ss.str(); 800 } 801 } 802 803 static std::string getBuildTool(uint32_t tools) { 804 switch (tools) { 805 case MachO::TOOL_CLANG: return "clang"; 806 case MachO::TOOL_SWIFT: return "swift"; 807 case MachO::TOOL_LD: return "ld"; 808 default: 809 std::string ret; 810 raw_string_ostream ss(ret); 811 ss << format_hex(tools, 8, true); 812 return ss.str(); 813 } 814 } 815 816 static std::string getVersionString(uint32_t version) { 817 uint32_t major = (version >> 16) & 0xffff; 818 uint32_t minor = (version >> 8) & 0xff; 819 uint32_t update = version & 0xff; 820 821 SmallString<32> Version; 822 Version = utostr(major) + "." + utostr(minor); 823 if (update != 0) 824 Version += "." + utostr(update); 825 return std::string(std::string(Version.str())); 826 } 827 828 /// If the input path is a .dSYM bundle (as created by the dsymutil tool), 829 /// return the paths to the object files found in the bundle, otherwise return 830 /// an empty vector. If the path appears to be a .dSYM bundle but no objects 831 /// were found or there was a filesystem error, then return an error. 832 static Expected<std::vector<std::string>> 833 findDsymObjectMembers(StringRef Path); 834 835 private: 836 MachOObjectFile(MemoryBufferRef Object, bool IsLittleEndian, bool Is64Bits, 837 Error &Err, uint32_t UniversalCputype = 0, 838 uint32_t UniversalIndex = 0); 839 840 uint64_t getSymbolValueImpl(DataRefImpl Symb) const override; 841 842 union { 843 MachO::mach_header_64 Header64; 844 MachO::mach_header Header; 845 }; 846 using SectionList = SmallVector<const char*, 1>; 847 SectionList Sections; 848 using LibraryList = SmallVector<const char*, 1>; 849 LibraryList Libraries; 850 LoadCommandList LoadCommands; 851 using LibraryShortName = SmallVector<StringRef, 1>; 852 using BuildToolList = SmallVector<const char*, 1>; 853 BuildToolList BuildTools; 854 mutable LibraryShortName LibrariesShortNames; 855 std::unique_ptr<BindRebaseSegInfo> BindRebaseSectionTable; 856 const char *SymtabLoadCmd = nullptr; 857 const char *DysymtabLoadCmd = nullptr; 858 const char *DataInCodeLoadCmd = nullptr; 859 const char *LinkOptHintsLoadCmd = nullptr; 860 const char *DyldInfoLoadCmd = nullptr; 861 const char *FuncStartsLoadCmd = nullptr; 862 const char *DyldChainedFixupsLoadCmd = nullptr; 863 const char *DyldExportsTrieLoadCmd = nullptr; 864 const char *UuidLoadCmd = nullptr; 865 bool HasPageZeroSegment = false; 866 }; 867 868 /// DiceRef 869 inline DiceRef::DiceRef(DataRefImpl DiceP, const ObjectFile *Owner) 870 : DicePimpl(DiceP) , OwningObject(Owner) {} 871 872 inline bool DiceRef::operator==(const DiceRef &Other) const { 873 return DicePimpl == Other.DicePimpl; 874 } 875 876 inline bool DiceRef::operator<(const DiceRef &Other) const { 877 return DicePimpl < Other.DicePimpl; 878 } 879 880 inline void DiceRef::moveNext() { 881 const MachO::data_in_code_entry *P = 882 reinterpret_cast<const MachO::data_in_code_entry *>(DicePimpl.p); 883 DicePimpl.p = reinterpret_cast<uintptr_t>(P + 1); 884 } 885 886 // Since a Mach-O data in code reference, a DiceRef, can only be created when 887 // the OwningObject ObjectFile is a MachOObjectFile a static_cast<> is used for 888 // the methods that get the values of the fields of the reference. 889 890 inline std::error_code DiceRef::getOffset(uint32_t &Result) const { 891 const MachOObjectFile *MachOOF = 892 static_cast<const MachOObjectFile *>(OwningObject); 893 MachO::data_in_code_entry Dice = MachOOF->getDice(DicePimpl); 894 Result = Dice.offset; 895 return std::error_code(); 896 } 897 898 inline std::error_code DiceRef::getLength(uint16_t &Result) const { 899 const MachOObjectFile *MachOOF = 900 static_cast<const MachOObjectFile *>(OwningObject); 901 MachO::data_in_code_entry Dice = MachOOF->getDice(DicePimpl); 902 Result = Dice.length; 903 return std::error_code(); 904 } 905 906 inline std::error_code DiceRef::getKind(uint16_t &Result) const { 907 const MachOObjectFile *MachOOF = 908 static_cast<const MachOObjectFile *>(OwningObject); 909 MachO::data_in_code_entry Dice = MachOOF->getDice(DicePimpl); 910 Result = Dice.kind; 911 return std::error_code(); 912 } 913 914 inline DataRefImpl DiceRef::getRawDataRefImpl() const { 915 return DicePimpl; 916 } 917 918 inline const ObjectFile *DiceRef::getObjectFile() const { 919 return OwningObject; 920 } 921 922 } // end namespace object 923 } // end namespace llvm 924 925 #endif // LLVM_OBJECT_MACHO_H 926