xref: /llvm-project/llvm/lib/Object/MachOObjectFile.cpp (revision d76e01a6a7c26051146fa65776cf63eb17f46fa3)
1 //===- MachOObjectFile.cpp - Mach-O object file binding -------------------===//
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 defines the MachOObjectFile class, which binds the MachOObject
10 // class to the generic ObjectFile wrapper.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "llvm/ADT/ArrayRef.h"
15 #include "llvm/ADT/None.h"
16 #include "llvm/ADT/STLExtras.h"
17 #include "llvm/ADT/SmallVector.h"
18 #include "llvm/ADT/StringRef.h"
19 #include "llvm/ADT/StringSwitch.h"
20 #include "llvm/ADT/Triple.h"
21 #include "llvm/ADT/Twine.h"
22 #include "llvm/BinaryFormat/MachO.h"
23 #include "llvm/Object/Error.h"
24 #include "llvm/Object/MachO.h"
25 #include "llvm/Object/ObjectFile.h"
26 #include "llvm/Object/SymbolicFile.h"
27 #include "llvm/Support/DataExtractor.h"
28 #include "llvm/Support/Debug.h"
29 #include "llvm/Support/Error.h"
30 #include "llvm/Support/ErrorHandling.h"
31 #include "llvm/Support/Format.h"
32 #include "llvm/Support/Host.h"
33 #include "llvm/Support/LEB128.h"
34 #include "llvm/Support/MemoryBuffer.h"
35 #include "llvm/Support/SwapByteOrder.h"
36 #include "llvm/Support/raw_ostream.h"
37 #include <algorithm>
38 #include <cassert>
39 #include <cstddef>
40 #include <cstdint>
41 #include <cstring>
42 #include <limits>
43 #include <list>
44 #include <memory>
45 #include <string>
46 #include <system_error>
47 
48 using namespace llvm;
49 using namespace object;
50 
51 namespace {
52 
53   struct section_base {
54     char sectname[16];
55     char segname[16];
56   };
57 
58 } // end anonymous namespace
59 
60 static Error malformedError(const Twine &Msg) {
61   return make_error<GenericBinaryError>("truncated or malformed object (" +
62                                             Msg + ")",
63                                         object_error::parse_failed);
64 }
65 
66 // FIXME: Replace all uses of this function with getStructOrErr.
67 template <typename T>
68 static T getStruct(const MachOObjectFile &O, const char *P) {
69   // Don't read before the beginning or past the end of the file
70   if (P < O.getData().begin() || P + sizeof(T) > O.getData().end())
71     report_fatal_error("Malformed MachO file.");
72 
73   T Cmd;
74   memcpy(&Cmd, P, sizeof(T));
75   if (O.isLittleEndian() != sys::IsLittleEndianHost)
76     MachO::swapStruct(Cmd);
77   return Cmd;
78 }
79 
80 template <typename T>
81 static Expected<T> getStructOrErr(const MachOObjectFile &O, const char *P) {
82   // Don't read before the beginning or past the end of the file
83   if (P < O.getData().begin() || P + sizeof(T) > O.getData().end())
84     return malformedError("Structure read out-of-range");
85 
86   T Cmd;
87   memcpy(&Cmd, P, sizeof(T));
88   if (O.isLittleEndian() != sys::IsLittleEndianHost)
89     MachO::swapStruct(Cmd);
90   return Cmd;
91 }
92 
93 static const char *
94 getSectionPtr(const MachOObjectFile &O, MachOObjectFile::LoadCommandInfo L,
95               unsigned Sec) {
96   uintptr_t CommandAddr = reinterpret_cast<uintptr_t>(L.Ptr);
97 
98   bool Is64 = O.is64Bit();
99   unsigned SegmentLoadSize = Is64 ? sizeof(MachO::segment_command_64) :
100                                     sizeof(MachO::segment_command);
101   unsigned SectionSize = Is64 ? sizeof(MachO::section_64) :
102                                 sizeof(MachO::section);
103 
104   uintptr_t SectionAddr = CommandAddr + SegmentLoadSize + Sec * SectionSize;
105   return reinterpret_cast<const char*>(SectionAddr);
106 }
107 
108 static const char *getPtr(const MachOObjectFile &O, size_t Offset) {
109   assert(Offset <= O.getData().size());
110   return O.getData().data() + Offset;
111 }
112 
113 static MachO::nlist_base
114 getSymbolTableEntryBase(const MachOObjectFile &O, DataRefImpl DRI) {
115   const char *P = reinterpret_cast<const char *>(DRI.p);
116   return getStruct<MachO::nlist_base>(O, P);
117 }
118 
119 static StringRef parseSegmentOrSectionName(const char *P) {
120   if (P[15] == 0)
121     // Null terminated.
122     return P;
123   // Not null terminated, so this is a 16 char string.
124   return StringRef(P, 16);
125 }
126 
127 static unsigned getCPUType(const MachOObjectFile &O) {
128   return O.getHeader().cputype;
129 }
130 
131 static unsigned getCPUSubType(const MachOObjectFile &O) {
132   return O.getHeader().cpusubtype;
133 }
134 
135 static uint32_t
136 getPlainRelocationAddress(const MachO::any_relocation_info &RE) {
137   return RE.r_word0;
138 }
139 
140 static unsigned
141 getScatteredRelocationAddress(const MachO::any_relocation_info &RE) {
142   return RE.r_word0 & 0xffffff;
143 }
144 
145 static bool getPlainRelocationPCRel(const MachOObjectFile &O,
146                                     const MachO::any_relocation_info &RE) {
147   if (O.isLittleEndian())
148     return (RE.r_word1 >> 24) & 1;
149   return (RE.r_word1 >> 7) & 1;
150 }
151 
152 static bool
153 getScatteredRelocationPCRel(const MachO::any_relocation_info &RE) {
154   return (RE.r_word0 >> 30) & 1;
155 }
156 
157 static unsigned getPlainRelocationLength(const MachOObjectFile &O,
158                                          const MachO::any_relocation_info &RE) {
159   if (O.isLittleEndian())
160     return (RE.r_word1 >> 25) & 3;
161   return (RE.r_word1 >> 5) & 3;
162 }
163 
164 static unsigned
165 getScatteredRelocationLength(const MachO::any_relocation_info &RE) {
166   return (RE.r_word0 >> 28) & 3;
167 }
168 
169 static unsigned getPlainRelocationType(const MachOObjectFile &O,
170                                        const MachO::any_relocation_info &RE) {
171   if (O.isLittleEndian())
172     return RE.r_word1 >> 28;
173   return RE.r_word1 & 0xf;
174 }
175 
176 static uint32_t getSectionFlags(const MachOObjectFile &O,
177                                 DataRefImpl Sec) {
178   if (O.is64Bit()) {
179     MachO::section_64 Sect = O.getSection64(Sec);
180     return Sect.flags;
181   }
182   MachO::section Sect = O.getSection(Sec);
183   return Sect.flags;
184 }
185 
186 static Expected<MachOObjectFile::LoadCommandInfo>
187 getLoadCommandInfo(const MachOObjectFile &Obj, const char *Ptr,
188                    uint32_t LoadCommandIndex) {
189   if (auto CmdOrErr = getStructOrErr<MachO::load_command>(Obj, Ptr)) {
190     if (CmdOrErr->cmdsize + Ptr > Obj.getData().end())
191       return malformedError("load command " + Twine(LoadCommandIndex) +
192                             " extends past end of file");
193     if (CmdOrErr->cmdsize < 8)
194       return malformedError("load command " + Twine(LoadCommandIndex) +
195                             " with size less than 8 bytes");
196     return MachOObjectFile::LoadCommandInfo({Ptr, *CmdOrErr});
197   } else
198     return CmdOrErr.takeError();
199 }
200 
201 static Expected<MachOObjectFile::LoadCommandInfo>
202 getFirstLoadCommandInfo(const MachOObjectFile &Obj) {
203   unsigned HeaderSize = Obj.is64Bit() ? sizeof(MachO::mach_header_64)
204                                       : sizeof(MachO::mach_header);
205   if (sizeof(MachO::load_command) > Obj.getHeader().sizeofcmds)
206     return malformedError("load command 0 extends past the end all load "
207                           "commands in the file");
208   return getLoadCommandInfo(Obj, getPtr(Obj, HeaderSize), 0);
209 }
210 
211 static Expected<MachOObjectFile::LoadCommandInfo>
212 getNextLoadCommandInfo(const MachOObjectFile &Obj, uint32_t LoadCommandIndex,
213                        const MachOObjectFile::LoadCommandInfo &L) {
214   unsigned HeaderSize = Obj.is64Bit() ? sizeof(MachO::mach_header_64)
215                                       : sizeof(MachO::mach_header);
216   if (L.Ptr + L.C.cmdsize + sizeof(MachO::load_command) >
217       Obj.getData().data() + HeaderSize + Obj.getHeader().sizeofcmds)
218     return malformedError("load command " + Twine(LoadCommandIndex + 1) +
219                           " extends past the end all load commands in the file");
220   return getLoadCommandInfo(Obj, L.Ptr + L.C.cmdsize, LoadCommandIndex + 1);
221 }
222 
223 template <typename T>
224 static void parseHeader(const MachOObjectFile &Obj, T &Header,
225                         Error &Err) {
226   if (sizeof(T) > Obj.getData().size()) {
227     Err = malformedError("the mach header extends past the end of the "
228                          "file");
229     return;
230   }
231   if (auto HeaderOrErr = getStructOrErr<T>(Obj, getPtr(Obj, 0)))
232     Header = *HeaderOrErr;
233   else
234     Err = HeaderOrErr.takeError();
235 }
236 
237 // This is used to check for overlapping of Mach-O elements.
238 struct MachOElement {
239   uint64_t Offset;
240   uint64_t Size;
241   const char *Name;
242 };
243 
244 static Error checkOverlappingElement(std::list<MachOElement> &Elements,
245                                      uint64_t Offset, uint64_t Size,
246                                      const char *Name) {
247   if (Size == 0)
248     return Error::success();
249 
250   for (auto it=Elements.begin() ; it != Elements.end(); ++it) {
251     auto E = *it;
252     if ((Offset >= E.Offset && Offset < E.Offset + E.Size) ||
253         (Offset + Size > E.Offset && Offset + Size < E.Offset + E.Size) ||
254         (Offset <= E.Offset && Offset + Size >= E.Offset + E.Size))
255       return malformedError(Twine(Name) + " at offset " + Twine(Offset) +
256                             " with a size of " + Twine(Size) + ", overlaps " +
257                             E.Name + " at offset " + Twine(E.Offset) + " with "
258                             "a size of " + Twine(E.Size));
259     auto nt = it;
260     nt++;
261     if (nt != Elements.end()) {
262       auto N = *nt;
263       if (Offset + Size <= N.Offset) {
264         Elements.insert(nt, {Offset, Size, Name});
265         return Error::success();
266       }
267     }
268   }
269   Elements.push_back({Offset, Size, Name});
270   return Error::success();
271 }
272 
273 // Parses LC_SEGMENT or LC_SEGMENT_64 load command, adds addresses of all
274 // sections to \param Sections, and optionally sets
275 // \param IsPageZeroSegment to true.
276 template <typename Segment, typename Section>
277 static Error parseSegmentLoadCommand(
278     const MachOObjectFile &Obj, const MachOObjectFile::LoadCommandInfo &Load,
279     SmallVectorImpl<const char *> &Sections, bool &IsPageZeroSegment,
280     uint32_t LoadCommandIndex, const char *CmdName, uint64_t SizeOfHeaders,
281     std::list<MachOElement> &Elements) {
282   const unsigned SegmentLoadSize = sizeof(Segment);
283   if (Load.C.cmdsize < SegmentLoadSize)
284     return malformedError("load command " + Twine(LoadCommandIndex) +
285                           " " + CmdName + " cmdsize too small");
286   if (auto SegOrErr = getStructOrErr<Segment>(Obj, Load.Ptr)) {
287     Segment S = SegOrErr.get();
288     const unsigned SectionSize = sizeof(Section);
289     uint64_t FileSize = Obj.getData().size();
290     if (S.nsects > std::numeric_limits<uint32_t>::max() / SectionSize ||
291         S.nsects * SectionSize > Load.C.cmdsize - SegmentLoadSize)
292       return malformedError("load command " + Twine(LoadCommandIndex) +
293                             " inconsistent cmdsize in " + CmdName +
294                             " for the number of sections");
295     for (unsigned J = 0; J < S.nsects; ++J) {
296       const char *Sec = getSectionPtr(Obj, Load, J);
297       Sections.push_back(Sec);
298       auto SectionOrErr = getStructOrErr<Section>(Obj, Sec);
299       if (!SectionOrErr)
300         return SectionOrErr.takeError();
301       Section s = SectionOrErr.get();
302       if (Obj.getHeader().filetype != MachO::MH_DYLIB_STUB &&
303           Obj.getHeader().filetype != MachO::MH_DSYM &&
304           s.flags != MachO::S_ZEROFILL &&
305           s.flags != MachO::S_THREAD_LOCAL_ZEROFILL &&
306           s.offset > FileSize)
307         return malformedError("offset field of section " + Twine(J) + " in " +
308                               CmdName + " command " + Twine(LoadCommandIndex) +
309                               " extends past the end of the file");
310       if (Obj.getHeader().filetype != MachO::MH_DYLIB_STUB &&
311           Obj.getHeader().filetype != MachO::MH_DSYM &&
312           s.flags != MachO::S_ZEROFILL &&
313           s.flags != MachO::S_THREAD_LOCAL_ZEROFILL && S.fileoff == 0 &&
314           s.offset < SizeOfHeaders && s.size != 0)
315         return malformedError("offset field of section " + Twine(J) + " in " +
316                               CmdName + " command " + Twine(LoadCommandIndex) +
317                               " not past the headers of the file");
318       uint64_t BigSize = s.offset;
319       BigSize += s.size;
320       if (Obj.getHeader().filetype != MachO::MH_DYLIB_STUB &&
321           Obj.getHeader().filetype != MachO::MH_DSYM &&
322           s.flags != MachO::S_ZEROFILL &&
323           s.flags != MachO::S_THREAD_LOCAL_ZEROFILL &&
324           BigSize > FileSize)
325         return malformedError("offset field plus size field of section " +
326                               Twine(J) + " in " + CmdName + " command " +
327                               Twine(LoadCommandIndex) +
328                               " extends past the end of the file");
329       if (Obj.getHeader().filetype != MachO::MH_DYLIB_STUB &&
330           Obj.getHeader().filetype != MachO::MH_DSYM &&
331           s.flags != MachO::S_ZEROFILL &&
332           s.flags != MachO::S_THREAD_LOCAL_ZEROFILL &&
333           s.size > S.filesize)
334         return malformedError("size field of section " +
335                               Twine(J) + " in " + CmdName + " command " +
336                               Twine(LoadCommandIndex) +
337                               " greater than the segment");
338       if (Obj.getHeader().filetype != MachO::MH_DYLIB_STUB &&
339           Obj.getHeader().filetype != MachO::MH_DSYM && s.size != 0 &&
340           s.addr < S.vmaddr)
341         return malformedError("addr field of section " + Twine(J) + " in " +
342                               CmdName + " command " + Twine(LoadCommandIndex) +
343                               " less than the segment's vmaddr");
344       BigSize = s.addr;
345       BigSize += s.size;
346       uint64_t BigEnd = S.vmaddr;
347       BigEnd += S.vmsize;
348       if (S.vmsize != 0 && s.size != 0 && BigSize > BigEnd)
349         return malformedError("addr field plus size of section " + Twine(J) +
350                               " in " + CmdName + " command " +
351                               Twine(LoadCommandIndex) +
352                               " greater than than "
353                               "the segment's vmaddr plus vmsize");
354       if (Obj.getHeader().filetype != MachO::MH_DYLIB_STUB &&
355           Obj.getHeader().filetype != MachO::MH_DSYM &&
356           s.flags != MachO::S_ZEROFILL &&
357           s.flags != MachO::S_THREAD_LOCAL_ZEROFILL)
358         if (Error Err = checkOverlappingElement(Elements, s.offset, s.size,
359                                                 "section contents"))
360           return Err;
361       if (s.reloff > FileSize)
362         return malformedError("reloff field of section " + Twine(J) + " in " +
363                               CmdName + " command " + Twine(LoadCommandIndex) +
364                               " extends past the end of the file");
365       BigSize = s.nreloc;
366       BigSize *= sizeof(struct MachO::relocation_info);
367       BigSize += s.reloff;
368       if (BigSize > FileSize)
369         return malformedError("reloff field plus nreloc field times sizeof("
370                               "struct relocation_info) of section " +
371                               Twine(J) + " in " + CmdName + " command " +
372                               Twine(LoadCommandIndex) +
373                               " extends past the end of the file");
374       if (Error Err = checkOverlappingElement(Elements, s.reloff, s.nreloc *
375                                               sizeof(struct
376                                               MachO::relocation_info),
377                                               "section relocation entries"))
378         return Err;
379     }
380     if (S.fileoff > FileSize)
381       return malformedError("load command " + Twine(LoadCommandIndex) +
382                             " fileoff field in " + CmdName +
383                             " extends past the end of the file");
384     uint64_t BigSize = S.fileoff;
385     BigSize += S.filesize;
386     if (BigSize > FileSize)
387       return malformedError("load command " + Twine(LoadCommandIndex) +
388                             " fileoff field plus filesize field in " +
389                             CmdName + " extends past the end of the file");
390     if (S.vmsize != 0 && S.filesize > S.vmsize)
391       return malformedError("load command " + Twine(LoadCommandIndex) +
392                             " filesize field in " + CmdName +
393                             " greater than vmsize field");
394     IsPageZeroSegment |= StringRef("__PAGEZERO").equals(S.segname);
395   } else
396     return SegOrErr.takeError();
397 
398   return Error::success();
399 }
400 
401 static Error checkSymtabCommand(const MachOObjectFile &Obj,
402                                 const MachOObjectFile::LoadCommandInfo &Load,
403                                 uint32_t LoadCommandIndex,
404                                 const char **SymtabLoadCmd,
405                                 std::list<MachOElement> &Elements) {
406   if (Load.C.cmdsize < sizeof(MachO::symtab_command))
407     return malformedError("load command " + Twine(LoadCommandIndex) +
408                           " LC_SYMTAB cmdsize too small");
409   if (*SymtabLoadCmd != nullptr)
410     return malformedError("more than one LC_SYMTAB command");
411   auto SymtabOrErr = getStructOrErr<MachO::symtab_command>(Obj, Load.Ptr);
412   if (!SymtabOrErr)
413     return SymtabOrErr.takeError();
414   MachO::symtab_command Symtab = SymtabOrErr.get();
415   if (Symtab.cmdsize != sizeof(MachO::symtab_command))
416     return malformedError("LC_SYMTAB command " + Twine(LoadCommandIndex) +
417                           " has incorrect cmdsize");
418   uint64_t FileSize = Obj.getData().size();
419   if (Symtab.symoff > FileSize)
420     return malformedError("symoff field of LC_SYMTAB command " +
421                           Twine(LoadCommandIndex) + " extends past the end "
422                           "of the file");
423   uint64_t SymtabSize = Symtab.nsyms;
424   const char *struct_nlist_name;
425   if (Obj.is64Bit()) {
426     SymtabSize *= sizeof(MachO::nlist_64);
427     struct_nlist_name = "struct nlist_64";
428   } else {
429     SymtabSize *= sizeof(MachO::nlist);
430     struct_nlist_name = "struct nlist";
431   }
432   uint64_t BigSize = SymtabSize;
433   BigSize += Symtab.symoff;
434   if (BigSize > FileSize)
435     return malformedError("symoff field plus nsyms field times sizeof(" +
436                           Twine(struct_nlist_name) + ") of LC_SYMTAB command " +
437                           Twine(LoadCommandIndex) + " extends past the end "
438                           "of the file");
439   if (Error Err = checkOverlappingElement(Elements, Symtab.symoff, SymtabSize,
440                                           "symbol table"))
441     return Err;
442   if (Symtab.stroff > FileSize)
443     return malformedError("stroff field of LC_SYMTAB command " +
444                           Twine(LoadCommandIndex) + " extends past the end "
445                           "of the file");
446   BigSize = Symtab.stroff;
447   BigSize += Symtab.strsize;
448   if (BigSize > FileSize)
449     return malformedError("stroff field plus strsize field of LC_SYMTAB "
450                           "command " + Twine(LoadCommandIndex) + " extends "
451                           "past the end of the file");
452   if (Error Err = checkOverlappingElement(Elements, Symtab.stroff,
453                                           Symtab.strsize, "string table"))
454     return Err;
455   *SymtabLoadCmd = Load.Ptr;
456   return Error::success();
457 }
458 
459 static Error checkDysymtabCommand(const MachOObjectFile &Obj,
460                                   const MachOObjectFile::LoadCommandInfo &Load,
461                                   uint32_t LoadCommandIndex,
462                                   const char **DysymtabLoadCmd,
463                                   std::list<MachOElement> &Elements) {
464   if (Load.C.cmdsize < sizeof(MachO::dysymtab_command))
465     return malformedError("load command " + Twine(LoadCommandIndex) +
466                           " LC_DYSYMTAB cmdsize too small");
467   if (*DysymtabLoadCmd != nullptr)
468     return malformedError("more than one LC_DYSYMTAB command");
469   auto DysymtabOrErr =
470     getStructOrErr<MachO::dysymtab_command>(Obj, Load.Ptr);
471   if (!DysymtabOrErr)
472     return DysymtabOrErr.takeError();
473   MachO::dysymtab_command Dysymtab = DysymtabOrErr.get();
474   if (Dysymtab.cmdsize != sizeof(MachO::dysymtab_command))
475     return malformedError("LC_DYSYMTAB command " + Twine(LoadCommandIndex) +
476                           " has incorrect cmdsize");
477   uint64_t FileSize = Obj.getData().size();
478   if (Dysymtab.tocoff > FileSize)
479     return malformedError("tocoff field of LC_DYSYMTAB command " +
480                           Twine(LoadCommandIndex) + " extends past the end of "
481                           "the file");
482   uint64_t BigSize = Dysymtab.ntoc;
483   BigSize *= sizeof(MachO::dylib_table_of_contents);
484   BigSize += Dysymtab.tocoff;
485   if (BigSize > FileSize)
486     return malformedError("tocoff field plus ntoc field times sizeof(struct "
487                           "dylib_table_of_contents) of LC_DYSYMTAB command " +
488                           Twine(LoadCommandIndex) + " extends past the end of "
489                           "the file");
490   if (Error Err = checkOverlappingElement(Elements, Dysymtab.tocoff,
491                                           Dysymtab.ntoc * sizeof(struct
492                                           MachO::dylib_table_of_contents),
493                                           "table of contents"))
494     return Err;
495   if (Dysymtab.modtaboff > FileSize)
496     return malformedError("modtaboff field of LC_DYSYMTAB command " +
497                           Twine(LoadCommandIndex) + " extends past the end of "
498                           "the file");
499   BigSize = Dysymtab.nmodtab;
500   const char *struct_dylib_module_name;
501   uint64_t sizeof_modtab;
502   if (Obj.is64Bit()) {
503     sizeof_modtab = sizeof(MachO::dylib_module_64);
504     struct_dylib_module_name = "struct dylib_module_64";
505   } else {
506     sizeof_modtab = sizeof(MachO::dylib_module);
507     struct_dylib_module_name = "struct dylib_module";
508   }
509   BigSize *= sizeof_modtab;
510   BigSize += Dysymtab.modtaboff;
511   if (BigSize > FileSize)
512     return malformedError("modtaboff field plus nmodtab field times sizeof(" +
513                           Twine(struct_dylib_module_name) + ") of LC_DYSYMTAB "
514                           "command " + Twine(LoadCommandIndex) + " extends "
515                           "past the end of the file");
516   if (Error Err = checkOverlappingElement(Elements, Dysymtab.modtaboff,
517                                           Dysymtab.nmodtab * sizeof_modtab,
518                                           "module table"))
519     return Err;
520   if (Dysymtab.extrefsymoff > FileSize)
521     return malformedError("extrefsymoff field of LC_DYSYMTAB command " +
522                           Twine(LoadCommandIndex) + " extends past the end of "
523                           "the file");
524   BigSize = Dysymtab.nextrefsyms;
525   BigSize *= sizeof(MachO::dylib_reference);
526   BigSize += Dysymtab.extrefsymoff;
527   if (BigSize > FileSize)
528     return malformedError("extrefsymoff field plus nextrefsyms field times "
529                           "sizeof(struct dylib_reference) of LC_DYSYMTAB "
530                           "command " + Twine(LoadCommandIndex) + " extends "
531                           "past the end of the file");
532   if (Error Err = checkOverlappingElement(Elements, Dysymtab.extrefsymoff,
533                                           Dysymtab.nextrefsyms *
534                                               sizeof(MachO::dylib_reference),
535                                           "reference table"))
536     return Err;
537   if (Dysymtab.indirectsymoff > FileSize)
538     return malformedError("indirectsymoff field of LC_DYSYMTAB command " +
539                           Twine(LoadCommandIndex) + " extends past the end of "
540                           "the file");
541   BigSize = Dysymtab.nindirectsyms;
542   BigSize *= sizeof(uint32_t);
543   BigSize += Dysymtab.indirectsymoff;
544   if (BigSize > FileSize)
545     return malformedError("indirectsymoff field plus nindirectsyms field times "
546                           "sizeof(uint32_t) of LC_DYSYMTAB command " +
547                           Twine(LoadCommandIndex) + " extends past the end of "
548                           "the file");
549   if (Error Err = checkOverlappingElement(Elements, Dysymtab.indirectsymoff,
550                                           Dysymtab.nindirectsyms *
551                                           sizeof(uint32_t),
552                                           "indirect table"))
553     return Err;
554   if (Dysymtab.extreloff > FileSize)
555     return malformedError("extreloff field of LC_DYSYMTAB command " +
556                           Twine(LoadCommandIndex) + " extends past the end of "
557                           "the file");
558   BigSize = Dysymtab.nextrel;
559   BigSize *= sizeof(MachO::relocation_info);
560   BigSize += Dysymtab.extreloff;
561   if (BigSize > FileSize)
562     return malformedError("extreloff field plus nextrel field times sizeof"
563                           "(struct relocation_info) of LC_DYSYMTAB command " +
564                           Twine(LoadCommandIndex) + " extends past the end of "
565                           "the file");
566   if (Error Err = checkOverlappingElement(Elements, Dysymtab.extreloff,
567                                           Dysymtab.nextrel *
568                                               sizeof(MachO::relocation_info),
569                                           "external relocation table"))
570     return Err;
571   if (Dysymtab.locreloff > FileSize)
572     return malformedError("locreloff field of LC_DYSYMTAB command " +
573                           Twine(LoadCommandIndex) + " extends past the end of "
574                           "the file");
575   BigSize = Dysymtab.nlocrel;
576   BigSize *= sizeof(MachO::relocation_info);
577   BigSize += Dysymtab.locreloff;
578   if (BigSize > FileSize)
579     return malformedError("locreloff field plus nlocrel field times sizeof"
580                           "(struct relocation_info) of LC_DYSYMTAB command " +
581                           Twine(LoadCommandIndex) + " extends past the end of "
582                           "the file");
583   if (Error Err = checkOverlappingElement(Elements, Dysymtab.locreloff,
584                                           Dysymtab.nlocrel *
585                                               sizeof(MachO::relocation_info),
586                                           "local relocation table"))
587     return Err;
588   *DysymtabLoadCmd = Load.Ptr;
589   return Error::success();
590 }
591 
592 static Error checkLinkeditDataCommand(const MachOObjectFile &Obj,
593                                  const MachOObjectFile::LoadCommandInfo &Load,
594                                  uint32_t LoadCommandIndex,
595                                  const char **LoadCmd, const char *CmdName,
596                                  std::list<MachOElement> &Elements,
597                                  const char *ElementName) {
598   if (Load.C.cmdsize < sizeof(MachO::linkedit_data_command))
599     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
600                           CmdName + " cmdsize too small");
601   if (*LoadCmd != nullptr)
602     return malformedError("more than one " + Twine(CmdName) + " command");
603   auto LinkDataOrError =
604     getStructOrErr<MachO::linkedit_data_command>(Obj, Load.Ptr);
605   if (!LinkDataOrError)
606     return LinkDataOrError.takeError();
607   MachO::linkedit_data_command LinkData = LinkDataOrError.get();
608   if (LinkData.cmdsize != sizeof(MachO::linkedit_data_command))
609     return malformedError(Twine(CmdName) + " command " +
610                           Twine(LoadCommandIndex) + " has incorrect cmdsize");
611   uint64_t FileSize = Obj.getData().size();
612   if (LinkData.dataoff > FileSize)
613     return malformedError("dataoff field of " + Twine(CmdName) + " command " +
614                           Twine(LoadCommandIndex) + " extends past the end of "
615                           "the file");
616   uint64_t BigSize = LinkData.dataoff;
617   BigSize += LinkData.datasize;
618   if (BigSize > FileSize)
619     return malformedError("dataoff field plus datasize field of " +
620                           Twine(CmdName) + " command " +
621                           Twine(LoadCommandIndex) + " extends past the end of "
622                           "the file");
623   if (Error Err = checkOverlappingElement(Elements, LinkData.dataoff,
624                                           LinkData.datasize, ElementName))
625     return Err;
626   *LoadCmd = Load.Ptr;
627   return Error::success();
628 }
629 
630 static Error checkDyldInfoCommand(const MachOObjectFile &Obj,
631                                   const MachOObjectFile::LoadCommandInfo &Load,
632                                   uint32_t LoadCommandIndex,
633                                   const char **LoadCmd, const char *CmdName,
634                                   std::list<MachOElement> &Elements) {
635   if (Load.C.cmdsize < sizeof(MachO::dyld_info_command))
636     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
637                           CmdName + " cmdsize too small");
638   if (*LoadCmd != nullptr)
639     return malformedError("more than one LC_DYLD_INFO and or LC_DYLD_INFO_ONLY "
640                           "command");
641   auto DyldInfoOrErr =
642     getStructOrErr<MachO::dyld_info_command>(Obj, Load.Ptr);
643   if (!DyldInfoOrErr)
644     return DyldInfoOrErr.takeError();
645   MachO::dyld_info_command DyldInfo = DyldInfoOrErr.get();
646   if (DyldInfo.cmdsize != sizeof(MachO::dyld_info_command))
647     return malformedError(Twine(CmdName) + " command " +
648                           Twine(LoadCommandIndex) + " has incorrect cmdsize");
649   uint64_t FileSize = Obj.getData().size();
650   if (DyldInfo.rebase_off > FileSize)
651     return malformedError("rebase_off field of " + Twine(CmdName) +
652                           " command " + Twine(LoadCommandIndex) + " extends "
653                           "past the end of the file");
654   uint64_t BigSize = DyldInfo.rebase_off;
655   BigSize += DyldInfo.rebase_size;
656   if (BigSize > FileSize)
657     return malformedError("rebase_off field plus rebase_size field of " +
658                           Twine(CmdName) + " command " +
659                           Twine(LoadCommandIndex) + " extends past the end of "
660                           "the file");
661   if (Error Err = checkOverlappingElement(Elements, DyldInfo.rebase_off,
662                                           DyldInfo.rebase_size,
663                                           "dyld rebase info"))
664     return Err;
665   if (DyldInfo.bind_off > FileSize)
666     return malformedError("bind_off field of " + Twine(CmdName) +
667                           " command " + Twine(LoadCommandIndex) + " extends "
668                           "past the end of the file");
669   BigSize = DyldInfo.bind_off;
670   BigSize += DyldInfo.bind_size;
671   if (BigSize > FileSize)
672     return malformedError("bind_off field plus bind_size field of " +
673                           Twine(CmdName) + " command " +
674                           Twine(LoadCommandIndex) + " extends past the end of "
675                           "the file");
676   if (Error Err = checkOverlappingElement(Elements, DyldInfo.bind_off,
677                                           DyldInfo.bind_size,
678                                           "dyld bind info"))
679     return Err;
680   if (DyldInfo.weak_bind_off > FileSize)
681     return malformedError("weak_bind_off field of " + Twine(CmdName) +
682                           " command " + Twine(LoadCommandIndex) + " extends "
683                           "past the end of the file");
684   BigSize = DyldInfo.weak_bind_off;
685   BigSize += DyldInfo.weak_bind_size;
686   if (BigSize > FileSize)
687     return malformedError("weak_bind_off field plus weak_bind_size field of " +
688                           Twine(CmdName) + " command " +
689                           Twine(LoadCommandIndex) + " extends past the end of "
690                           "the file");
691   if (Error Err = checkOverlappingElement(Elements, DyldInfo.weak_bind_off,
692                                           DyldInfo.weak_bind_size,
693                                           "dyld weak bind info"))
694     return Err;
695   if (DyldInfo.lazy_bind_off > FileSize)
696     return malformedError("lazy_bind_off field of " + Twine(CmdName) +
697                           " command " + Twine(LoadCommandIndex) + " extends "
698                           "past the end of the file");
699   BigSize = DyldInfo.lazy_bind_off;
700   BigSize += DyldInfo.lazy_bind_size;
701   if (BigSize > FileSize)
702     return malformedError("lazy_bind_off field plus lazy_bind_size field of " +
703                           Twine(CmdName) + " command " +
704                           Twine(LoadCommandIndex) + " extends past the end of "
705                           "the file");
706   if (Error Err = checkOverlappingElement(Elements, DyldInfo.lazy_bind_off,
707                                           DyldInfo.lazy_bind_size,
708                                           "dyld lazy bind info"))
709     return Err;
710   if (DyldInfo.export_off > FileSize)
711     return malformedError("export_off field of " + Twine(CmdName) +
712                           " command " + Twine(LoadCommandIndex) + " extends "
713                           "past the end of the file");
714   BigSize = DyldInfo.export_off;
715   BigSize += DyldInfo.export_size;
716   if (BigSize > FileSize)
717     return malformedError("export_off field plus export_size field of " +
718                           Twine(CmdName) + " command " +
719                           Twine(LoadCommandIndex) + " extends past the end of "
720                           "the file");
721   if (Error Err = checkOverlappingElement(Elements, DyldInfo.export_off,
722                                           DyldInfo.export_size,
723                                           "dyld export info"))
724     return Err;
725   *LoadCmd = Load.Ptr;
726   return Error::success();
727 }
728 
729 static Error checkDylibCommand(const MachOObjectFile &Obj,
730                                const MachOObjectFile::LoadCommandInfo &Load,
731                                uint32_t LoadCommandIndex, const char *CmdName) {
732   if (Load.C.cmdsize < sizeof(MachO::dylib_command))
733     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
734                           CmdName + " cmdsize too small");
735   auto CommandOrErr = getStructOrErr<MachO::dylib_command>(Obj, Load.Ptr);
736   if (!CommandOrErr)
737     return CommandOrErr.takeError();
738   MachO::dylib_command D = CommandOrErr.get();
739   if (D.dylib.name < sizeof(MachO::dylib_command))
740     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
741                           CmdName + " name.offset field too small, not past "
742                           "the end of the dylib_command struct");
743   if (D.dylib.name >= D.cmdsize)
744     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
745                           CmdName + " name.offset field extends past the end "
746                           "of the load command");
747   // Make sure there is a null between the starting offset of the name and
748   // the end of the load command.
749   uint32_t i;
750   const char *P = (const char *)Load.Ptr;
751   for (i = D.dylib.name; i < D.cmdsize; i++)
752     if (P[i] == '\0')
753       break;
754   if (i >= D.cmdsize)
755     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
756                           CmdName + " library name extends past the end of the "
757                           "load command");
758   return Error::success();
759 }
760 
761 static Error checkDylibIdCommand(const MachOObjectFile &Obj,
762                                  const MachOObjectFile::LoadCommandInfo &Load,
763                                  uint32_t LoadCommandIndex,
764                                  const char **LoadCmd) {
765   if (Error Err = checkDylibCommand(Obj, Load, LoadCommandIndex,
766                                      "LC_ID_DYLIB"))
767     return Err;
768   if (*LoadCmd != nullptr)
769     return malformedError("more than one LC_ID_DYLIB command");
770   if (Obj.getHeader().filetype != MachO::MH_DYLIB &&
771       Obj.getHeader().filetype != MachO::MH_DYLIB_STUB)
772     return malformedError("LC_ID_DYLIB load command in non-dynamic library "
773                           "file type");
774   *LoadCmd = Load.Ptr;
775   return Error::success();
776 }
777 
778 static Error checkDyldCommand(const MachOObjectFile &Obj,
779                               const MachOObjectFile::LoadCommandInfo &Load,
780                               uint32_t LoadCommandIndex, const char *CmdName) {
781   if (Load.C.cmdsize < sizeof(MachO::dylinker_command))
782     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
783                           CmdName + " cmdsize too small");
784   auto CommandOrErr = getStructOrErr<MachO::dylinker_command>(Obj, Load.Ptr);
785   if (!CommandOrErr)
786     return CommandOrErr.takeError();
787   MachO::dylinker_command D = CommandOrErr.get();
788   if (D.name < sizeof(MachO::dylinker_command))
789     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
790                           CmdName + " name.offset field too small, not past "
791                           "the end of the dylinker_command struct");
792   if (D.name >= D.cmdsize)
793     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
794                           CmdName + " name.offset field extends past the end "
795                           "of the load command");
796   // Make sure there is a null between the starting offset of the name and
797   // the end of the load command.
798   uint32_t i;
799   const char *P = (const char *)Load.Ptr;
800   for (i = D.name; i < D.cmdsize; i++)
801     if (P[i] == '\0')
802       break;
803   if (i >= D.cmdsize)
804     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
805                           CmdName + " dyld name extends past the end of the "
806                           "load command");
807   return Error::success();
808 }
809 
810 static Error checkVersCommand(const MachOObjectFile &Obj,
811                               const MachOObjectFile::LoadCommandInfo &Load,
812                               uint32_t LoadCommandIndex,
813                               const char **LoadCmd, const char *CmdName) {
814   if (Load.C.cmdsize != sizeof(MachO::version_min_command))
815     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
816                           CmdName + " has incorrect cmdsize");
817   if (*LoadCmd != nullptr)
818     return malformedError("more than one LC_VERSION_MIN_MACOSX, "
819                           "LC_VERSION_MIN_IPHONEOS, LC_VERSION_MIN_TVOS or "
820                           "LC_VERSION_MIN_WATCHOS command");
821   *LoadCmd = Load.Ptr;
822   return Error::success();
823 }
824 
825 static Error checkNoteCommand(const MachOObjectFile &Obj,
826                               const MachOObjectFile::LoadCommandInfo &Load,
827                               uint32_t LoadCommandIndex,
828                               std::list<MachOElement> &Elements) {
829   if (Load.C.cmdsize != sizeof(MachO::note_command))
830     return malformedError("load command " + Twine(LoadCommandIndex) +
831                           " LC_NOTE has incorrect cmdsize");
832   auto NoteCmdOrErr = getStructOrErr<MachO::note_command>(Obj, Load.Ptr);
833   if (!NoteCmdOrErr)
834     return NoteCmdOrErr.takeError();
835   MachO::note_command Nt = NoteCmdOrErr.get();
836   uint64_t FileSize = Obj.getData().size();
837   if (Nt.offset > FileSize)
838     return malformedError("offset field of LC_NOTE command " +
839                           Twine(LoadCommandIndex) + " extends "
840                           "past the end of the file");
841   uint64_t BigSize = Nt.offset;
842   BigSize += Nt.size;
843   if (BigSize > FileSize)
844     return malformedError("size field plus offset field of LC_NOTE command " +
845                           Twine(LoadCommandIndex) + " extends past the end of "
846                           "the file");
847   if (Error Err = checkOverlappingElement(Elements, Nt.offset, Nt.size,
848                                           "LC_NOTE data"))
849     return Err;
850   return Error::success();
851 }
852 
853 static Error
854 parseBuildVersionCommand(const MachOObjectFile &Obj,
855                          const MachOObjectFile::LoadCommandInfo &Load,
856                          SmallVectorImpl<const char*> &BuildTools,
857                          uint32_t LoadCommandIndex) {
858   auto BVCOrErr =
859     getStructOrErr<MachO::build_version_command>(Obj, Load.Ptr);
860   if (!BVCOrErr)
861     return BVCOrErr.takeError();
862   MachO::build_version_command BVC = BVCOrErr.get();
863   if (Load.C.cmdsize !=
864       sizeof(MachO::build_version_command) +
865           BVC.ntools * sizeof(MachO::build_tool_version))
866     return malformedError("load command " + Twine(LoadCommandIndex) +
867                           " LC_BUILD_VERSION_COMMAND has incorrect cmdsize");
868 
869   auto Start = Load.Ptr + sizeof(MachO::build_version_command);
870   BuildTools.resize(BVC.ntools);
871   for (unsigned i = 0; i < BVC.ntools; ++i)
872     BuildTools[i] = Start + i * sizeof(MachO::build_tool_version);
873 
874   return Error::success();
875 }
876 
877 static Error checkRpathCommand(const MachOObjectFile &Obj,
878                                const MachOObjectFile::LoadCommandInfo &Load,
879                                uint32_t LoadCommandIndex) {
880   if (Load.C.cmdsize < sizeof(MachO::rpath_command))
881     return malformedError("load command " + Twine(LoadCommandIndex) +
882                           " LC_RPATH cmdsize too small");
883   auto ROrErr = getStructOrErr<MachO::rpath_command>(Obj, Load.Ptr);
884   if (!ROrErr)
885     return ROrErr.takeError();
886   MachO::rpath_command R = ROrErr.get();
887   if (R.path < sizeof(MachO::rpath_command))
888     return malformedError("load command " + Twine(LoadCommandIndex) +
889                           " LC_RPATH path.offset field too small, not past "
890                           "the end of the rpath_command struct");
891   if (R.path >= R.cmdsize)
892     return malformedError("load command " + Twine(LoadCommandIndex) +
893                           " LC_RPATH path.offset field extends past the end "
894                           "of the load command");
895   // Make sure there is a null between the starting offset of the path and
896   // the end of the load command.
897   uint32_t i;
898   const char *P = (const char *)Load.Ptr;
899   for (i = R.path; i < R.cmdsize; i++)
900     if (P[i] == '\0')
901       break;
902   if (i >= R.cmdsize)
903     return malformedError("load command " + Twine(LoadCommandIndex) +
904                           " LC_RPATH library name extends past the end of the "
905                           "load command");
906   return Error::success();
907 }
908 
909 static Error checkEncryptCommand(const MachOObjectFile &Obj,
910                                  const MachOObjectFile::LoadCommandInfo &Load,
911                                  uint32_t LoadCommandIndex,
912                                  uint64_t cryptoff, uint64_t cryptsize,
913                                  const char **LoadCmd, const char *CmdName) {
914   if (*LoadCmd != nullptr)
915     return malformedError("more than one LC_ENCRYPTION_INFO and or "
916                           "LC_ENCRYPTION_INFO_64 command");
917   uint64_t FileSize = Obj.getData().size();
918   if (cryptoff > FileSize)
919     return malformedError("cryptoff field of " + Twine(CmdName) +
920                           " command " + Twine(LoadCommandIndex) + " extends "
921                           "past the end of the file");
922   uint64_t BigSize = cryptoff;
923   BigSize += cryptsize;
924   if (BigSize > FileSize)
925     return malformedError("cryptoff field plus cryptsize field of " +
926                           Twine(CmdName) + " command " +
927                           Twine(LoadCommandIndex) + " extends past the end of "
928                           "the file");
929   *LoadCmd = Load.Ptr;
930   return Error::success();
931 }
932 
933 static Error checkLinkerOptCommand(const MachOObjectFile &Obj,
934                                    const MachOObjectFile::LoadCommandInfo &Load,
935                                    uint32_t LoadCommandIndex) {
936   if (Load.C.cmdsize < sizeof(MachO::linker_option_command))
937     return malformedError("load command " + Twine(LoadCommandIndex) +
938                           " LC_LINKER_OPTION cmdsize too small");
939   auto LinkOptionOrErr =
940     getStructOrErr<MachO::linker_option_command>(Obj, Load.Ptr);
941   if (!LinkOptionOrErr)
942     return LinkOptionOrErr.takeError();
943   MachO::linker_option_command L = LinkOptionOrErr.get();
944   // Make sure the count of strings is correct.
945   const char *string = (const char *)Load.Ptr +
946                        sizeof(struct MachO::linker_option_command);
947   uint32_t left = L.cmdsize - sizeof(struct MachO::linker_option_command);
948   uint32_t i = 0;
949   while (left > 0) {
950     while (*string == '\0' && left > 0) {
951       string++;
952       left--;
953     }
954     if (left > 0) {
955       i++;
956       uint32_t NullPos = StringRef(string, left).find('\0');
957       if (0xffffffff == NullPos)
958         return malformedError("load command " + Twine(LoadCommandIndex) +
959                               " LC_LINKER_OPTION string #" + Twine(i) +
960                               " is not NULL terminated");
961       uint32_t len = std::min(NullPos, left) + 1;
962       string += len;
963       left -= len;
964     }
965   }
966   if (L.count != i)
967     return malformedError("load command " + Twine(LoadCommandIndex) +
968                           " LC_LINKER_OPTION string count " + Twine(L.count) +
969                           " does not match number of strings");
970   return Error::success();
971 }
972 
973 static Error checkSubCommand(const MachOObjectFile &Obj,
974                              const MachOObjectFile::LoadCommandInfo &Load,
975                              uint32_t LoadCommandIndex, const char *CmdName,
976                              size_t SizeOfCmd, const char *CmdStructName,
977                              uint32_t PathOffset, const char *PathFieldName) {
978   if (PathOffset < SizeOfCmd)
979     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
980                           CmdName + " " + PathFieldName + ".offset field too "
981                           "small, not past the end of the " + CmdStructName);
982   if (PathOffset >= Load.C.cmdsize)
983     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
984                           CmdName + " " + PathFieldName + ".offset field "
985                           "extends past the end of the load command");
986   // Make sure there is a null between the starting offset of the path and
987   // the end of the load command.
988   uint32_t i;
989   const char *P = (const char *)Load.Ptr;
990   for (i = PathOffset; i < Load.C.cmdsize; i++)
991     if (P[i] == '\0')
992       break;
993   if (i >= Load.C.cmdsize)
994     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
995                           CmdName + " " + PathFieldName + " name extends past "
996                           "the end of the load command");
997   return Error::success();
998 }
999 
1000 static Error checkThreadCommand(const MachOObjectFile &Obj,
1001                                 const MachOObjectFile::LoadCommandInfo &Load,
1002                                 uint32_t LoadCommandIndex,
1003                                 const char *CmdName) {
1004   if (Load.C.cmdsize < sizeof(MachO::thread_command))
1005     return malformedError("load command " + Twine(LoadCommandIndex) +
1006                           CmdName + " cmdsize too small");
1007   auto ThreadCommandOrErr =
1008     getStructOrErr<MachO::thread_command>(Obj, Load.Ptr);
1009   if (!ThreadCommandOrErr)
1010     return ThreadCommandOrErr.takeError();
1011   MachO::thread_command T = ThreadCommandOrErr.get();
1012   const char *state = Load.Ptr + sizeof(MachO::thread_command);
1013   const char *end = Load.Ptr + T.cmdsize;
1014   uint32_t nflavor = 0;
1015   uint32_t cputype = getCPUType(Obj);
1016   while (state < end) {
1017     if(state + sizeof(uint32_t) > end)
1018       return malformedError("load command " + Twine(LoadCommandIndex) +
1019                             "flavor in " + CmdName + " extends past end of "
1020                             "command");
1021     uint32_t flavor;
1022     memcpy(&flavor, state, sizeof(uint32_t));
1023     if (Obj.isLittleEndian() != sys::IsLittleEndianHost)
1024       sys::swapByteOrder(flavor);
1025     state += sizeof(uint32_t);
1026 
1027     if(state + sizeof(uint32_t) > end)
1028       return malformedError("load command " + Twine(LoadCommandIndex) +
1029                             " count in " + CmdName + " extends past end of "
1030                             "command");
1031     uint32_t count;
1032     memcpy(&count, state, sizeof(uint32_t));
1033     if (Obj.isLittleEndian() != sys::IsLittleEndianHost)
1034       sys::swapByteOrder(count);
1035     state += sizeof(uint32_t);
1036 
1037     if (cputype == MachO::CPU_TYPE_I386) {
1038       if (flavor == MachO::x86_THREAD_STATE32) {
1039         if (count != MachO::x86_THREAD_STATE32_COUNT)
1040           return malformedError("load command " + Twine(LoadCommandIndex) +
1041                                 " count not x86_THREAD_STATE32_COUNT for "
1042                                 "flavor number " + Twine(nflavor) + " which is "
1043                                 "a x86_THREAD_STATE32 flavor in " + CmdName +
1044                                 " command");
1045         if (state + sizeof(MachO::x86_thread_state32_t) > end)
1046           return malformedError("load command " + Twine(LoadCommandIndex) +
1047                                 " x86_THREAD_STATE32 extends past end of "
1048                                 "command in " + CmdName + " command");
1049         state += sizeof(MachO::x86_thread_state32_t);
1050       } else {
1051         return malformedError("load command " + Twine(LoadCommandIndex) +
1052                               " unknown flavor (" + Twine(flavor) + ") for "
1053                               "flavor number " + Twine(nflavor) + " in " +
1054                               CmdName + " command");
1055       }
1056     } else if (cputype == MachO::CPU_TYPE_X86_64) {
1057       if (flavor == MachO::x86_THREAD_STATE) {
1058         if (count != MachO::x86_THREAD_STATE_COUNT)
1059           return malformedError("load command " + Twine(LoadCommandIndex) +
1060                                 " count not x86_THREAD_STATE_COUNT for "
1061                                 "flavor number " + Twine(nflavor) + " which is "
1062                                 "a x86_THREAD_STATE flavor in " + CmdName +
1063                                 " command");
1064         if (state + sizeof(MachO::x86_thread_state_t) > end)
1065           return malformedError("load command " + Twine(LoadCommandIndex) +
1066                                 " x86_THREAD_STATE extends past end of "
1067                                 "command in " + CmdName + " command");
1068         state += sizeof(MachO::x86_thread_state_t);
1069       } else if (flavor == MachO::x86_FLOAT_STATE) {
1070         if (count != MachO::x86_FLOAT_STATE_COUNT)
1071           return malformedError("load command " + Twine(LoadCommandIndex) +
1072                                 " count not x86_FLOAT_STATE_COUNT for "
1073                                 "flavor number " + Twine(nflavor) + " which is "
1074                                 "a x86_FLOAT_STATE flavor in " + CmdName +
1075                                 " command");
1076         if (state + sizeof(MachO::x86_float_state_t) > end)
1077           return malformedError("load command " + Twine(LoadCommandIndex) +
1078                                 " x86_FLOAT_STATE extends past end of "
1079                                 "command in " + CmdName + " command");
1080         state += sizeof(MachO::x86_float_state_t);
1081       } else if (flavor == MachO::x86_EXCEPTION_STATE) {
1082         if (count != MachO::x86_EXCEPTION_STATE_COUNT)
1083           return malformedError("load command " + Twine(LoadCommandIndex) +
1084                                 " count not x86_EXCEPTION_STATE_COUNT for "
1085                                 "flavor number " + Twine(nflavor) + " which is "
1086                                 "a x86_EXCEPTION_STATE flavor in " + CmdName +
1087                                 " command");
1088         if (state + sizeof(MachO::x86_exception_state_t) > end)
1089           return malformedError("load command " + Twine(LoadCommandIndex) +
1090                                 " x86_EXCEPTION_STATE extends past end of "
1091                                 "command in " + CmdName + " command");
1092         state += sizeof(MachO::x86_exception_state_t);
1093       } else if (flavor == MachO::x86_THREAD_STATE64) {
1094         if (count != MachO::x86_THREAD_STATE64_COUNT)
1095           return malformedError("load command " + Twine(LoadCommandIndex) +
1096                                 " count not x86_THREAD_STATE64_COUNT for "
1097                                 "flavor number " + Twine(nflavor) + " which is "
1098                                 "a x86_THREAD_STATE64 flavor in " + CmdName +
1099                                 " command");
1100         if (state + sizeof(MachO::x86_thread_state64_t) > end)
1101           return malformedError("load command " + Twine(LoadCommandIndex) +
1102                                 " x86_THREAD_STATE64 extends past end of "
1103                                 "command in " + CmdName + " command");
1104         state += sizeof(MachO::x86_thread_state64_t);
1105       } else if (flavor == MachO::x86_EXCEPTION_STATE64) {
1106         if (count != MachO::x86_EXCEPTION_STATE64_COUNT)
1107           return malformedError("load command " + Twine(LoadCommandIndex) +
1108                                 " count not x86_EXCEPTION_STATE64_COUNT for "
1109                                 "flavor number " + Twine(nflavor) + " which is "
1110                                 "a x86_EXCEPTION_STATE64 flavor in " + CmdName +
1111                                 " command");
1112         if (state + sizeof(MachO::x86_exception_state64_t) > end)
1113           return malformedError("load command " + Twine(LoadCommandIndex) +
1114                                 " x86_EXCEPTION_STATE64 extends past end of "
1115                                 "command in " + CmdName + " command");
1116         state += sizeof(MachO::x86_exception_state64_t);
1117       } else {
1118         return malformedError("load command " + Twine(LoadCommandIndex) +
1119                               " unknown flavor (" + Twine(flavor) + ") for "
1120                               "flavor number " + Twine(nflavor) + " in " +
1121                               CmdName + " command");
1122       }
1123     } else if (cputype == MachO::CPU_TYPE_ARM) {
1124       if (flavor == MachO::ARM_THREAD_STATE) {
1125         if (count != MachO::ARM_THREAD_STATE_COUNT)
1126           return malformedError("load command " + Twine(LoadCommandIndex) +
1127                                 " count not ARM_THREAD_STATE_COUNT for "
1128                                 "flavor number " + Twine(nflavor) + " which is "
1129                                 "a ARM_THREAD_STATE flavor in " + CmdName +
1130                                 " command");
1131         if (state + sizeof(MachO::arm_thread_state32_t) > end)
1132           return malformedError("load command " + Twine(LoadCommandIndex) +
1133                                 " ARM_THREAD_STATE extends past end of "
1134                                 "command in " + CmdName + " command");
1135         state += sizeof(MachO::arm_thread_state32_t);
1136       } else {
1137         return malformedError("load command " + Twine(LoadCommandIndex) +
1138                               " unknown flavor (" + Twine(flavor) + ") for "
1139                               "flavor number " + Twine(nflavor) + " in " +
1140                               CmdName + " command");
1141       }
1142     } else if (cputype == MachO::CPU_TYPE_ARM64 ||
1143                cputype == MachO::CPU_TYPE_ARM64_32) {
1144       if (flavor == MachO::ARM_THREAD_STATE64) {
1145         if (count != MachO::ARM_THREAD_STATE64_COUNT)
1146           return malformedError("load command " + Twine(LoadCommandIndex) +
1147                                 " count not ARM_THREAD_STATE64_COUNT for "
1148                                 "flavor number " + Twine(nflavor) + " which is "
1149                                 "a ARM_THREAD_STATE64 flavor in " + CmdName +
1150                                 " command");
1151         if (state + sizeof(MachO::arm_thread_state64_t) > end)
1152           return malformedError("load command " + Twine(LoadCommandIndex) +
1153                                 " ARM_THREAD_STATE64 extends past end of "
1154                                 "command in " + CmdName + " command");
1155         state += sizeof(MachO::arm_thread_state64_t);
1156       } else {
1157         return malformedError("load command " + Twine(LoadCommandIndex) +
1158                               " unknown flavor (" + Twine(flavor) + ") for "
1159                               "flavor number " + Twine(nflavor) + " in " +
1160                               CmdName + " command");
1161       }
1162     } else if (cputype == MachO::CPU_TYPE_POWERPC) {
1163       if (flavor == MachO::PPC_THREAD_STATE) {
1164         if (count != MachO::PPC_THREAD_STATE_COUNT)
1165           return malformedError("load command " + Twine(LoadCommandIndex) +
1166                                 " count not PPC_THREAD_STATE_COUNT for "
1167                                 "flavor number " + Twine(nflavor) + " which is "
1168                                 "a PPC_THREAD_STATE flavor in " + CmdName +
1169                                 " command");
1170         if (state + sizeof(MachO::ppc_thread_state32_t) > end)
1171           return malformedError("load command " + Twine(LoadCommandIndex) +
1172                                 " PPC_THREAD_STATE extends past end of "
1173                                 "command in " + CmdName + " command");
1174         state += sizeof(MachO::ppc_thread_state32_t);
1175       } else {
1176         return malformedError("load command " + Twine(LoadCommandIndex) +
1177                               " unknown flavor (" + Twine(flavor) + ") for "
1178                               "flavor number " + Twine(nflavor) + " in " +
1179                               CmdName + " command");
1180       }
1181     } else {
1182       return malformedError("unknown cputype (" + Twine(cputype) + ") load "
1183                             "command " + Twine(LoadCommandIndex) + " for " +
1184                             CmdName + " command can't be checked");
1185     }
1186     nflavor++;
1187   }
1188   return Error::success();
1189 }
1190 
1191 static Error checkTwoLevelHintsCommand(const MachOObjectFile &Obj,
1192                                        const MachOObjectFile::LoadCommandInfo
1193                                          &Load,
1194                                        uint32_t LoadCommandIndex,
1195                                        const char **LoadCmd,
1196                                        std::list<MachOElement> &Elements) {
1197   if (Load.C.cmdsize != sizeof(MachO::twolevel_hints_command))
1198     return malformedError("load command " + Twine(LoadCommandIndex) +
1199                           " LC_TWOLEVEL_HINTS has incorrect cmdsize");
1200   if (*LoadCmd != nullptr)
1201     return malformedError("more than one LC_TWOLEVEL_HINTS command");
1202   auto HintsOrErr = getStructOrErr<MachO::twolevel_hints_command>(Obj, Load.Ptr);
1203   if(!HintsOrErr)
1204     return HintsOrErr.takeError();
1205   MachO::twolevel_hints_command Hints = HintsOrErr.get();
1206   uint64_t FileSize = Obj.getData().size();
1207   if (Hints.offset > FileSize)
1208     return malformedError("offset field of LC_TWOLEVEL_HINTS command " +
1209                           Twine(LoadCommandIndex) + " extends past the end of "
1210                           "the file");
1211   uint64_t BigSize = Hints.nhints;
1212   BigSize *= sizeof(MachO::twolevel_hint);
1213   BigSize += Hints.offset;
1214   if (BigSize > FileSize)
1215     return malformedError("offset field plus nhints times sizeof(struct "
1216                           "twolevel_hint) field of LC_TWOLEVEL_HINTS command " +
1217                           Twine(LoadCommandIndex) + " extends past the end of "
1218                           "the file");
1219   if (Error Err = checkOverlappingElement(Elements, Hints.offset, Hints.nhints *
1220                                           sizeof(MachO::twolevel_hint),
1221                                           "two level hints"))
1222     return Err;
1223   *LoadCmd = Load.Ptr;
1224   return Error::success();
1225 }
1226 
1227 // Returns true if the libObject code does not support the load command and its
1228 // contents.  The cmd value it is treated as an unknown load command but with
1229 // an error message that says the cmd value is obsolete.
1230 static bool isLoadCommandObsolete(uint32_t cmd) {
1231   if (cmd == MachO::LC_SYMSEG ||
1232       cmd == MachO::LC_LOADFVMLIB ||
1233       cmd == MachO::LC_IDFVMLIB ||
1234       cmd == MachO::LC_IDENT ||
1235       cmd == MachO::LC_FVMFILE ||
1236       cmd == MachO::LC_PREPAGE ||
1237       cmd == MachO::LC_PREBOUND_DYLIB ||
1238       cmd == MachO::LC_TWOLEVEL_HINTS ||
1239       cmd == MachO::LC_PREBIND_CKSUM)
1240     return true;
1241   return false;
1242 }
1243 
1244 Expected<std::unique_ptr<MachOObjectFile>>
1245 MachOObjectFile::create(MemoryBufferRef Object, bool IsLittleEndian,
1246                         bool Is64Bits, uint32_t UniversalCputype,
1247                         uint32_t UniversalIndex) {
1248   Error Err = Error::success();
1249   std::unique_ptr<MachOObjectFile> Obj(
1250       new MachOObjectFile(std::move(Object), IsLittleEndian,
1251                           Is64Bits, Err, UniversalCputype,
1252                           UniversalIndex));
1253   if (Err)
1254     return std::move(Err);
1255   return std::move(Obj);
1256 }
1257 
1258 MachOObjectFile::MachOObjectFile(MemoryBufferRef Object, bool IsLittleEndian,
1259                                  bool Is64bits, Error &Err,
1260                                  uint32_t UniversalCputype,
1261                                  uint32_t UniversalIndex)
1262     : ObjectFile(getMachOType(IsLittleEndian, Is64bits), Object) {
1263   ErrorAsOutParameter ErrAsOutParam(&Err);
1264   uint64_t SizeOfHeaders;
1265   uint32_t cputype;
1266   if (is64Bit()) {
1267     parseHeader(*this, Header64, Err);
1268     SizeOfHeaders = sizeof(MachO::mach_header_64);
1269     cputype = Header64.cputype;
1270   } else {
1271     parseHeader(*this, Header, Err);
1272     SizeOfHeaders = sizeof(MachO::mach_header);
1273     cputype = Header.cputype;
1274   }
1275   if (Err)
1276     return;
1277   SizeOfHeaders += getHeader().sizeofcmds;
1278   if (getData().data() + SizeOfHeaders > getData().end()) {
1279     Err = malformedError("load commands extend past the end of the file");
1280     return;
1281   }
1282   if (UniversalCputype != 0 && cputype != UniversalCputype) {
1283     Err = malformedError("universal header architecture: " +
1284                          Twine(UniversalIndex) + "'s cputype does not match "
1285                          "object file's mach header");
1286     return;
1287   }
1288   std::list<MachOElement> Elements;
1289   Elements.push_back({0, SizeOfHeaders, "Mach-O headers"});
1290 
1291   uint32_t LoadCommandCount = getHeader().ncmds;
1292   LoadCommandInfo Load;
1293   if (LoadCommandCount != 0) {
1294     if (auto LoadOrErr = getFirstLoadCommandInfo(*this))
1295       Load = *LoadOrErr;
1296     else {
1297       Err = LoadOrErr.takeError();
1298       return;
1299     }
1300   }
1301 
1302   const char *DyldIdLoadCmd = nullptr;
1303   const char *FuncStartsLoadCmd = nullptr;
1304   const char *SplitInfoLoadCmd = nullptr;
1305   const char *CodeSignDrsLoadCmd = nullptr;
1306   const char *CodeSignLoadCmd = nullptr;
1307   const char *VersLoadCmd = nullptr;
1308   const char *SourceLoadCmd = nullptr;
1309   const char *EntryPointLoadCmd = nullptr;
1310   const char *EncryptLoadCmd = nullptr;
1311   const char *RoutinesLoadCmd = nullptr;
1312   const char *UnixThreadLoadCmd = nullptr;
1313   const char *TwoLevelHintsLoadCmd = nullptr;
1314   for (unsigned I = 0; I < LoadCommandCount; ++I) {
1315     if (is64Bit()) {
1316       if (Load.C.cmdsize % 8 != 0) {
1317         // We have a hack here to allow 64-bit Mach-O core files to have
1318         // LC_THREAD commands that are only a multiple of 4 and not 8 to be
1319         // allowed since the macOS kernel produces them.
1320         if (getHeader().filetype != MachO::MH_CORE ||
1321             Load.C.cmd != MachO::LC_THREAD || Load.C.cmdsize % 4) {
1322           Err = malformedError("load command " + Twine(I) + " cmdsize not a "
1323                                "multiple of 8");
1324           return;
1325         }
1326       }
1327     } else {
1328       if (Load.C.cmdsize % 4 != 0) {
1329         Err = malformedError("load command " + Twine(I) + " cmdsize not a "
1330                              "multiple of 4");
1331         return;
1332       }
1333     }
1334     LoadCommands.push_back(Load);
1335     if (Load.C.cmd == MachO::LC_SYMTAB) {
1336       if ((Err = checkSymtabCommand(*this, Load, I, &SymtabLoadCmd, Elements)))
1337         return;
1338     } else if (Load.C.cmd == MachO::LC_DYSYMTAB) {
1339       if ((Err = checkDysymtabCommand(*this, Load, I, &DysymtabLoadCmd,
1340                                       Elements)))
1341         return;
1342     } else if (Load.C.cmd == MachO::LC_DATA_IN_CODE) {
1343       if ((Err = checkLinkeditDataCommand(*this, Load, I, &DataInCodeLoadCmd,
1344                                           "LC_DATA_IN_CODE", Elements,
1345                                           "data in code info")))
1346         return;
1347     } else if (Load.C.cmd == MachO::LC_LINKER_OPTIMIZATION_HINT) {
1348       if ((Err = checkLinkeditDataCommand(*this, Load, I, &LinkOptHintsLoadCmd,
1349                                           "LC_LINKER_OPTIMIZATION_HINT",
1350                                           Elements, "linker optimization "
1351                                           "hints")))
1352         return;
1353     } else if (Load.C.cmd == MachO::LC_FUNCTION_STARTS) {
1354       if ((Err = checkLinkeditDataCommand(*this, Load, I, &FuncStartsLoadCmd,
1355                                           "LC_FUNCTION_STARTS", Elements,
1356                                           "function starts data")))
1357         return;
1358     } else if (Load.C.cmd == MachO::LC_SEGMENT_SPLIT_INFO) {
1359       if ((Err = checkLinkeditDataCommand(*this, Load, I, &SplitInfoLoadCmd,
1360                                           "LC_SEGMENT_SPLIT_INFO", Elements,
1361                                           "split info data")))
1362         return;
1363     } else if (Load.C.cmd == MachO::LC_DYLIB_CODE_SIGN_DRS) {
1364       if ((Err = checkLinkeditDataCommand(*this, Load, I, &CodeSignDrsLoadCmd,
1365                                           "LC_DYLIB_CODE_SIGN_DRS", Elements,
1366                                           "code signing RDs data")))
1367         return;
1368     } else if (Load.C.cmd == MachO::LC_CODE_SIGNATURE) {
1369       if ((Err = checkLinkeditDataCommand(*this, Load, I, &CodeSignLoadCmd,
1370                                           "LC_CODE_SIGNATURE", Elements,
1371                                           "code signature data")))
1372         return;
1373     } else if (Load.C.cmd == MachO::LC_DYLD_INFO) {
1374       if ((Err = checkDyldInfoCommand(*this, Load, I, &DyldInfoLoadCmd,
1375                                       "LC_DYLD_INFO", Elements)))
1376         return;
1377     } else if (Load.C.cmd == MachO::LC_DYLD_INFO_ONLY) {
1378       if ((Err = checkDyldInfoCommand(*this, Load, I, &DyldInfoLoadCmd,
1379                                       "LC_DYLD_INFO_ONLY", Elements)))
1380         return;
1381     } else if (Load.C.cmd == MachO::LC_UUID) {
1382       if (Load.C.cmdsize != sizeof(MachO::uuid_command)) {
1383         Err = malformedError("LC_UUID command " + Twine(I) + " has incorrect "
1384                              "cmdsize");
1385         return;
1386       }
1387       if (UuidLoadCmd) {
1388         Err = malformedError("more than one LC_UUID command");
1389         return;
1390       }
1391       UuidLoadCmd = Load.Ptr;
1392     } else if (Load.C.cmd == MachO::LC_SEGMENT_64) {
1393       if ((Err = parseSegmentLoadCommand<MachO::segment_command_64,
1394                                          MachO::section_64>(
1395                    *this, Load, Sections, HasPageZeroSegment, I,
1396                    "LC_SEGMENT_64", SizeOfHeaders, Elements)))
1397         return;
1398     } else if (Load.C.cmd == MachO::LC_SEGMENT) {
1399       if ((Err = parseSegmentLoadCommand<MachO::segment_command,
1400                                          MachO::section>(
1401                    *this, Load, Sections, HasPageZeroSegment, I,
1402                    "LC_SEGMENT", SizeOfHeaders, Elements)))
1403         return;
1404     } else if (Load.C.cmd == MachO::LC_ID_DYLIB) {
1405       if ((Err = checkDylibIdCommand(*this, Load, I, &DyldIdLoadCmd)))
1406         return;
1407     } else if (Load.C.cmd == MachO::LC_LOAD_DYLIB) {
1408       if ((Err = checkDylibCommand(*this, Load, I, "LC_LOAD_DYLIB")))
1409         return;
1410       Libraries.push_back(Load.Ptr);
1411     } else if (Load.C.cmd == MachO::LC_LOAD_WEAK_DYLIB) {
1412       if ((Err = checkDylibCommand(*this, Load, I, "LC_LOAD_WEAK_DYLIB")))
1413         return;
1414       Libraries.push_back(Load.Ptr);
1415     } else if (Load.C.cmd == MachO::LC_LAZY_LOAD_DYLIB) {
1416       if ((Err = checkDylibCommand(*this, Load, I, "LC_LAZY_LOAD_DYLIB")))
1417         return;
1418       Libraries.push_back(Load.Ptr);
1419     } else if (Load.C.cmd == MachO::LC_REEXPORT_DYLIB) {
1420       if ((Err = checkDylibCommand(*this, Load, I, "LC_REEXPORT_DYLIB")))
1421         return;
1422       Libraries.push_back(Load.Ptr);
1423     } else if (Load.C.cmd == MachO::LC_LOAD_UPWARD_DYLIB) {
1424       if ((Err = checkDylibCommand(*this, Load, I, "LC_LOAD_UPWARD_DYLIB")))
1425         return;
1426       Libraries.push_back(Load.Ptr);
1427     } else if (Load.C.cmd == MachO::LC_ID_DYLINKER) {
1428       if ((Err = checkDyldCommand(*this, Load, I, "LC_ID_DYLINKER")))
1429         return;
1430     } else if (Load.C.cmd == MachO::LC_LOAD_DYLINKER) {
1431       if ((Err = checkDyldCommand(*this, Load, I, "LC_LOAD_DYLINKER")))
1432         return;
1433     } else if (Load.C.cmd == MachO::LC_DYLD_ENVIRONMENT) {
1434       if ((Err = checkDyldCommand(*this, Load, I, "LC_DYLD_ENVIRONMENT")))
1435         return;
1436     } else if (Load.C.cmd == MachO::LC_VERSION_MIN_MACOSX) {
1437       if ((Err = checkVersCommand(*this, Load, I, &VersLoadCmd,
1438                                   "LC_VERSION_MIN_MACOSX")))
1439         return;
1440     } else if (Load.C.cmd == MachO::LC_VERSION_MIN_IPHONEOS) {
1441       if ((Err = checkVersCommand(*this, Load, I, &VersLoadCmd,
1442                                   "LC_VERSION_MIN_IPHONEOS")))
1443         return;
1444     } else if (Load.C.cmd == MachO::LC_VERSION_MIN_TVOS) {
1445       if ((Err = checkVersCommand(*this, Load, I, &VersLoadCmd,
1446                                   "LC_VERSION_MIN_TVOS")))
1447         return;
1448     } else if (Load.C.cmd == MachO::LC_VERSION_MIN_WATCHOS) {
1449       if ((Err = checkVersCommand(*this, Load, I, &VersLoadCmd,
1450                                   "LC_VERSION_MIN_WATCHOS")))
1451         return;
1452     } else if (Load.C.cmd == MachO::LC_NOTE) {
1453       if ((Err = checkNoteCommand(*this, Load, I, Elements)))
1454         return;
1455     } else if (Load.C.cmd == MachO::LC_BUILD_VERSION) {
1456       if ((Err = parseBuildVersionCommand(*this, Load, BuildTools, I)))
1457         return;
1458     } else if (Load.C.cmd == MachO::LC_RPATH) {
1459       if ((Err = checkRpathCommand(*this, Load, I)))
1460         return;
1461     } else if (Load.C.cmd == MachO::LC_SOURCE_VERSION) {
1462       if (Load.C.cmdsize != sizeof(MachO::source_version_command)) {
1463         Err = malformedError("LC_SOURCE_VERSION command " + Twine(I) +
1464                              " has incorrect cmdsize");
1465         return;
1466       }
1467       if (SourceLoadCmd) {
1468         Err = malformedError("more than one LC_SOURCE_VERSION command");
1469         return;
1470       }
1471       SourceLoadCmd = Load.Ptr;
1472     } else if (Load.C.cmd == MachO::LC_MAIN) {
1473       if (Load.C.cmdsize != sizeof(MachO::entry_point_command)) {
1474         Err = malformedError("LC_MAIN command " + Twine(I) +
1475                              " has incorrect cmdsize");
1476         return;
1477       }
1478       if (EntryPointLoadCmd) {
1479         Err = malformedError("more than one LC_MAIN command");
1480         return;
1481       }
1482       EntryPointLoadCmd = Load.Ptr;
1483     } else if (Load.C.cmd == MachO::LC_ENCRYPTION_INFO) {
1484       if (Load.C.cmdsize != sizeof(MachO::encryption_info_command)) {
1485         Err = malformedError("LC_ENCRYPTION_INFO command " + Twine(I) +
1486                              " has incorrect cmdsize");
1487         return;
1488       }
1489       MachO::encryption_info_command E =
1490         getStruct<MachO::encryption_info_command>(*this, Load.Ptr);
1491       if ((Err = checkEncryptCommand(*this, Load, I, E.cryptoff, E.cryptsize,
1492                                      &EncryptLoadCmd, "LC_ENCRYPTION_INFO")))
1493         return;
1494     } else if (Load.C.cmd == MachO::LC_ENCRYPTION_INFO_64) {
1495       if (Load.C.cmdsize != sizeof(MachO::encryption_info_command_64)) {
1496         Err = malformedError("LC_ENCRYPTION_INFO_64 command " + Twine(I) +
1497                              " has incorrect cmdsize");
1498         return;
1499       }
1500       MachO::encryption_info_command_64 E =
1501         getStruct<MachO::encryption_info_command_64>(*this, Load.Ptr);
1502       if ((Err = checkEncryptCommand(*this, Load, I, E.cryptoff, E.cryptsize,
1503                                      &EncryptLoadCmd, "LC_ENCRYPTION_INFO_64")))
1504         return;
1505     } else if (Load.C.cmd == MachO::LC_LINKER_OPTION) {
1506       if ((Err = checkLinkerOptCommand(*this, Load, I)))
1507         return;
1508     } else if (Load.C.cmd == MachO::LC_SUB_FRAMEWORK) {
1509       if (Load.C.cmdsize < sizeof(MachO::sub_framework_command)) {
1510         Err =  malformedError("load command " + Twine(I) +
1511                               " LC_SUB_FRAMEWORK cmdsize too small");
1512         return;
1513       }
1514       MachO::sub_framework_command S =
1515         getStruct<MachO::sub_framework_command>(*this, Load.Ptr);
1516       if ((Err = checkSubCommand(*this, Load, I, "LC_SUB_FRAMEWORK",
1517                                  sizeof(MachO::sub_framework_command),
1518                                  "sub_framework_command", S.umbrella,
1519                                  "umbrella")))
1520         return;
1521     } else if (Load.C.cmd == MachO::LC_SUB_UMBRELLA) {
1522       if (Load.C.cmdsize < sizeof(MachO::sub_umbrella_command)) {
1523         Err =  malformedError("load command " + Twine(I) +
1524                               " LC_SUB_UMBRELLA cmdsize too small");
1525         return;
1526       }
1527       MachO::sub_umbrella_command S =
1528         getStruct<MachO::sub_umbrella_command>(*this, Load.Ptr);
1529       if ((Err = checkSubCommand(*this, Load, I, "LC_SUB_UMBRELLA",
1530                                  sizeof(MachO::sub_umbrella_command),
1531                                  "sub_umbrella_command", S.sub_umbrella,
1532                                  "sub_umbrella")))
1533         return;
1534     } else if (Load.C.cmd == MachO::LC_SUB_LIBRARY) {
1535       if (Load.C.cmdsize < sizeof(MachO::sub_library_command)) {
1536         Err =  malformedError("load command " + Twine(I) +
1537                               " LC_SUB_LIBRARY cmdsize too small");
1538         return;
1539       }
1540       MachO::sub_library_command S =
1541         getStruct<MachO::sub_library_command>(*this, Load.Ptr);
1542       if ((Err = checkSubCommand(*this, Load, I, "LC_SUB_LIBRARY",
1543                                  sizeof(MachO::sub_library_command),
1544                                  "sub_library_command", S.sub_library,
1545                                  "sub_library")))
1546         return;
1547     } else if (Load.C.cmd == MachO::LC_SUB_CLIENT) {
1548       if (Load.C.cmdsize < sizeof(MachO::sub_client_command)) {
1549         Err =  malformedError("load command " + Twine(I) +
1550                               " LC_SUB_CLIENT cmdsize too small");
1551         return;
1552       }
1553       MachO::sub_client_command S =
1554         getStruct<MachO::sub_client_command>(*this, Load.Ptr);
1555       if ((Err = checkSubCommand(*this, Load, I, "LC_SUB_CLIENT",
1556                                  sizeof(MachO::sub_client_command),
1557                                  "sub_client_command", S.client, "client")))
1558         return;
1559     } else if (Load.C.cmd == MachO::LC_ROUTINES) {
1560       if (Load.C.cmdsize != sizeof(MachO::routines_command)) {
1561         Err = malformedError("LC_ROUTINES command " + Twine(I) +
1562                              " has incorrect cmdsize");
1563         return;
1564       }
1565       if (RoutinesLoadCmd) {
1566         Err = malformedError("more than one LC_ROUTINES and or LC_ROUTINES_64 "
1567                              "command");
1568         return;
1569       }
1570       RoutinesLoadCmd = Load.Ptr;
1571     } else if (Load.C.cmd == MachO::LC_ROUTINES_64) {
1572       if (Load.C.cmdsize != sizeof(MachO::routines_command_64)) {
1573         Err = malformedError("LC_ROUTINES_64 command " + Twine(I) +
1574                              " has incorrect cmdsize");
1575         return;
1576       }
1577       if (RoutinesLoadCmd) {
1578         Err = malformedError("more than one LC_ROUTINES_64 and or LC_ROUTINES "
1579                              "command");
1580         return;
1581       }
1582       RoutinesLoadCmd = Load.Ptr;
1583     } else if (Load.C.cmd == MachO::LC_UNIXTHREAD) {
1584       if ((Err = checkThreadCommand(*this, Load, I, "LC_UNIXTHREAD")))
1585         return;
1586       if (UnixThreadLoadCmd) {
1587         Err = malformedError("more than one LC_UNIXTHREAD command");
1588         return;
1589       }
1590       UnixThreadLoadCmd = Load.Ptr;
1591     } else if (Load.C.cmd == MachO::LC_THREAD) {
1592       if ((Err = checkThreadCommand(*this, Load, I, "LC_THREAD")))
1593         return;
1594     // Note: LC_TWOLEVEL_HINTS is really obsolete and is not supported.
1595     } else if (Load.C.cmd == MachO::LC_TWOLEVEL_HINTS) {
1596        if ((Err = checkTwoLevelHintsCommand(*this, Load, I,
1597                                             &TwoLevelHintsLoadCmd, Elements)))
1598          return;
1599     } else if (Load.C.cmd == MachO::LC_IDENT) {
1600       // Note: LC_IDENT is ignored.
1601       continue;
1602     } else if (isLoadCommandObsolete(Load.C.cmd)) {
1603       Err = malformedError("load command " + Twine(I) + " for cmd value of: " +
1604                            Twine(Load.C.cmd) + " is obsolete and not "
1605                            "supported");
1606       return;
1607     }
1608     // TODO: generate a error for unknown load commands by default.  But still
1609     // need work out an approach to allow or not allow unknown values like this
1610     // as an option for some uses like lldb.
1611     if (I < LoadCommandCount - 1) {
1612       if (auto LoadOrErr = getNextLoadCommandInfo(*this, I, Load))
1613         Load = *LoadOrErr;
1614       else {
1615         Err = LoadOrErr.takeError();
1616         return;
1617       }
1618     }
1619   }
1620   if (!SymtabLoadCmd) {
1621     if (DysymtabLoadCmd) {
1622       Err = malformedError("contains LC_DYSYMTAB load command without a "
1623                            "LC_SYMTAB load command");
1624       return;
1625     }
1626   } else if (DysymtabLoadCmd) {
1627     MachO::symtab_command Symtab =
1628       getStruct<MachO::symtab_command>(*this, SymtabLoadCmd);
1629     MachO::dysymtab_command Dysymtab =
1630       getStruct<MachO::dysymtab_command>(*this, DysymtabLoadCmd);
1631     if (Dysymtab.nlocalsym != 0 && Dysymtab.ilocalsym > Symtab.nsyms) {
1632       Err = malformedError("ilocalsym in LC_DYSYMTAB load command "
1633                            "extends past the end of the symbol table");
1634       return;
1635     }
1636     uint64_t BigSize = Dysymtab.ilocalsym;
1637     BigSize += Dysymtab.nlocalsym;
1638     if (Dysymtab.nlocalsym != 0 && BigSize > Symtab.nsyms) {
1639       Err = malformedError("ilocalsym plus nlocalsym in LC_DYSYMTAB load "
1640                            "command extends past the end of the symbol table");
1641       return;
1642     }
1643     if (Dysymtab.nextdefsym != 0 && Dysymtab.iextdefsym > Symtab.nsyms) {
1644       Err = malformedError("iextdefsym in LC_DYSYMTAB load command "
1645                            "extends past the end of the symbol table");
1646       return;
1647     }
1648     BigSize = Dysymtab.iextdefsym;
1649     BigSize += Dysymtab.nextdefsym;
1650     if (Dysymtab.nextdefsym != 0 && BigSize > Symtab.nsyms) {
1651       Err = malformedError("iextdefsym plus nextdefsym in LC_DYSYMTAB "
1652                            "load command extends past the end of the symbol "
1653                            "table");
1654       return;
1655     }
1656     if (Dysymtab.nundefsym != 0 && Dysymtab.iundefsym > Symtab.nsyms) {
1657       Err = malformedError("iundefsym in LC_DYSYMTAB load command "
1658                            "extends past the end of the symbol table");
1659       return;
1660     }
1661     BigSize = Dysymtab.iundefsym;
1662     BigSize += Dysymtab.nundefsym;
1663     if (Dysymtab.nundefsym != 0 && BigSize > Symtab.nsyms) {
1664       Err = malformedError("iundefsym plus nundefsym in LC_DYSYMTAB load "
1665                            " command extends past the end of the symbol table");
1666       return;
1667     }
1668   }
1669   if ((getHeader().filetype == MachO::MH_DYLIB ||
1670        getHeader().filetype == MachO::MH_DYLIB_STUB) &&
1671        DyldIdLoadCmd == nullptr) {
1672     Err = malformedError("no LC_ID_DYLIB load command in dynamic library "
1673                          "filetype");
1674     return;
1675   }
1676   assert(LoadCommands.size() == LoadCommandCount);
1677 
1678   Err = Error::success();
1679 }
1680 
1681 Error MachOObjectFile::checkSymbolTable() const {
1682   uint32_t Flags = 0;
1683   if (is64Bit()) {
1684     MachO::mach_header_64 H_64 = MachOObjectFile::getHeader64();
1685     Flags = H_64.flags;
1686   } else {
1687     MachO::mach_header H = MachOObjectFile::getHeader();
1688     Flags = H.flags;
1689   }
1690   uint8_t NType = 0;
1691   uint8_t NSect = 0;
1692   uint16_t NDesc = 0;
1693   uint32_t NStrx = 0;
1694   uint64_t NValue = 0;
1695   uint32_t SymbolIndex = 0;
1696   MachO::symtab_command S = getSymtabLoadCommand();
1697   for (const SymbolRef &Symbol : symbols()) {
1698     DataRefImpl SymDRI = Symbol.getRawDataRefImpl();
1699     if (is64Bit()) {
1700       MachO::nlist_64 STE_64 = getSymbol64TableEntry(SymDRI);
1701       NType = STE_64.n_type;
1702       NSect = STE_64.n_sect;
1703       NDesc = STE_64.n_desc;
1704       NStrx = STE_64.n_strx;
1705       NValue = STE_64.n_value;
1706     } else {
1707       MachO::nlist STE = getSymbolTableEntry(SymDRI);
1708       NType = STE.n_type;
1709       NSect = STE.n_sect;
1710       NDesc = STE.n_desc;
1711       NStrx = STE.n_strx;
1712       NValue = STE.n_value;
1713     }
1714     if ((NType & MachO::N_STAB) == 0) {
1715       if ((NType & MachO::N_TYPE) == MachO::N_SECT) {
1716         if (NSect == 0 || NSect > Sections.size())
1717           return malformedError("bad section index: " + Twine((int)NSect) +
1718                                 " for symbol at index " + Twine(SymbolIndex));
1719       }
1720       if ((NType & MachO::N_TYPE) == MachO::N_INDR) {
1721         if (NValue >= S.strsize)
1722           return malformedError("bad n_value: " + Twine((int)NValue) + " past "
1723                                 "the end of string table, for N_INDR symbol at "
1724                                 "index " + Twine(SymbolIndex));
1725       }
1726       if ((Flags & MachO::MH_TWOLEVEL) == MachO::MH_TWOLEVEL &&
1727           (((NType & MachO::N_TYPE) == MachO::N_UNDF && NValue == 0) ||
1728            (NType & MachO::N_TYPE) == MachO::N_PBUD)) {
1729             uint32_t LibraryOrdinal = MachO::GET_LIBRARY_ORDINAL(NDesc);
1730             if (LibraryOrdinal != 0 &&
1731                 LibraryOrdinal != MachO::EXECUTABLE_ORDINAL &&
1732                 LibraryOrdinal != MachO::DYNAMIC_LOOKUP_ORDINAL &&
1733                 LibraryOrdinal - 1 >= Libraries.size() ) {
1734               return malformedError("bad library ordinal: " + Twine(LibraryOrdinal) +
1735                                     " for symbol at index " + Twine(SymbolIndex));
1736             }
1737           }
1738     }
1739     if (NStrx >= S.strsize)
1740       return malformedError("bad string table index: " + Twine((int)NStrx) +
1741                             " past the end of string table, for symbol at "
1742                             "index " + Twine(SymbolIndex));
1743     SymbolIndex++;
1744   }
1745   return Error::success();
1746 }
1747 
1748 void MachOObjectFile::moveSymbolNext(DataRefImpl &Symb) const {
1749   unsigned SymbolTableEntrySize = is64Bit() ?
1750     sizeof(MachO::nlist_64) :
1751     sizeof(MachO::nlist);
1752   Symb.p += SymbolTableEntrySize;
1753 }
1754 
1755 Expected<StringRef> MachOObjectFile::getSymbolName(DataRefImpl Symb) const {
1756   StringRef StringTable = getStringTableData();
1757   MachO::nlist_base Entry = getSymbolTableEntryBase(*this, Symb);
1758   if (Entry.n_strx == 0)
1759     // A n_strx value of 0 indicates that no name is associated with a
1760     // particular symbol table entry.
1761     return StringRef();
1762   const char *Start = &StringTable.data()[Entry.n_strx];
1763   if (Start < getData().begin() || Start >= getData().end()) {
1764     return malformedError("bad string index: " + Twine(Entry.n_strx) +
1765                           " for symbol at index " + Twine(getSymbolIndex(Symb)));
1766   }
1767   return StringRef(Start);
1768 }
1769 
1770 unsigned MachOObjectFile::getSectionType(SectionRef Sec) const {
1771   DataRefImpl DRI = Sec.getRawDataRefImpl();
1772   uint32_t Flags = getSectionFlags(*this, DRI);
1773   return Flags & MachO::SECTION_TYPE;
1774 }
1775 
1776 uint64_t MachOObjectFile::getNValue(DataRefImpl Sym) const {
1777   if (is64Bit()) {
1778     MachO::nlist_64 Entry = getSymbol64TableEntry(Sym);
1779     return Entry.n_value;
1780   }
1781   MachO::nlist Entry = getSymbolTableEntry(Sym);
1782   return Entry.n_value;
1783 }
1784 
1785 // getIndirectName() returns the name of the alias'ed symbol who's string table
1786 // index is in the n_value field.
1787 std::error_code MachOObjectFile::getIndirectName(DataRefImpl Symb,
1788                                                  StringRef &Res) const {
1789   StringRef StringTable = getStringTableData();
1790   MachO::nlist_base Entry = getSymbolTableEntryBase(*this, Symb);
1791   if ((Entry.n_type & MachO::N_TYPE) != MachO::N_INDR)
1792     return object_error::parse_failed;
1793   uint64_t NValue = getNValue(Symb);
1794   if (NValue >= StringTable.size())
1795     return object_error::parse_failed;
1796   const char *Start = &StringTable.data()[NValue];
1797   Res = StringRef(Start);
1798   return std::error_code();
1799 }
1800 
1801 uint64_t MachOObjectFile::getSymbolValueImpl(DataRefImpl Sym) const {
1802   return getNValue(Sym);
1803 }
1804 
1805 Expected<uint64_t> MachOObjectFile::getSymbolAddress(DataRefImpl Sym) const {
1806   return getSymbolValue(Sym);
1807 }
1808 
1809 uint32_t MachOObjectFile::getSymbolAlignment(DataRefImpl DRI) const {
1810   uint32_t Flags = cantFail(getSymbolFlags(DRI));
1811   if (Flags & SymbolRef::SF_Common) {
1812     MachO::nlist_base Entry = getSymbolTableEntryBase(*this, DRI);
1813     return 1 << MachO::GET_COMM_ALIGN(Entry.n_desc);
1814   }
1815   return 0;
1816 }
1817 
1818 uint64_t MachOObjectFile::getCommonSymbolSizeImpl(DataRefImpl DRI) const {
1819   return getNValue(DRI);
1820 }
1821 
1822 Expected<SymbolRef::Type>
1823 MachOObjectFile::getSymbolType(DataRefImpl Symb) const {
1824   MachO::nlist_base Entry = getSymbolTableEntryBase(*this, Symb);
1825   uint8_t n_type = Entry.n_type;
1826 
1827   // If this is a STAB debugging symbol, we can do nothing more.
1828   if (n_type & MachO::N_STAB)
1829     return SymbolRef::ST_Debug;
1830 
1831   switch (n_type & MachO::N_TYPE) {
1832     case MachO::N_UNDF :
1833       return SymbolRef::ST_Unknown;
1834     case MachO::N_SECT :
1835       Expected<section_iterator> SecOrError = getSymbolSection(Symb);
1836       if (!SecOrError)
1837         return SecOrError.takeError();
1838       section_iterator Sec = *SecOrError;
1839       if (Sec->isData() || Sec->isBSS())
1840         return SymbolRef::ST_Data;
1841       return SymbolRef::ST_Function;
1842   }
1843   return SymbolRef::ST_Other;
1844 }
1845 
1846 Expected<uint32_t> MachOObjectFile::getSymbolFlags(DataRefImpl DRI) const {
1847   MachO::nlist_base Entry = getSymbolTableEntryBase(*this, DRI);
1848 
1849   uint8_t MachOType = Entry.n_type;
1850   uint16_t MachOFlags = Entry.n_desc;
1851 
1852   uint32_t Result = SymbolRef::SF_None;
1853 
1854   if ((MachOType & MachO::N_TYPE) == MachO::N_INDR)
1855     Result |= SymbolRef::SF_Indirect;
1856 
1857   if (MachOType & MachO::N_STAB)
1858     Result |= SymbolRef::SF_FormatSpecific;
1859 
1860   if (MachOType & MachO::N_EXT) {
1861     Result |= SymbolRef::SF_Global;
1862     if ((MachOType & MachO::N_TYPE) == MachO::N_UNDF) {
1863       if (getNValue(DRI))
1864         Result |= SymbolRef::SF_Common;
1865       else
1866         Result |= SymbolRef::SF_Undefined;
1867     }
1868 
1869     if (!(MachOType & MachO::N_PEXT))
1870       Result |= SymbolRef::SF_Exported;
1871   }
1872 
1873   if (MachOFlags & (MachO::N_WEAK_REF | MachO::N_WEAK_DEF))
1874     Result |= SymbolRef::SF_Weak;
1875 
1876   if (MachOFlags & (MachO::N_ARM_THUMB_DEF))
1877     Result |= SymbolRef::SF_Thumb;
1878 
1879   if ((MachOType & MachO::N_TYPE) == MachO::N_ABS)
1880     Result |= SymbolRef::SF_Absolute;
1881 
1882   return Result;
1883 }
1884 
1885 Expected<section_iterator>
1886 MachOObjectFile::getSymbolSection(DataRefImpl Symb) const {
1887   MachO::nlist_base Entry = getSymbolTableEntryBase(*this, Symb);
1888   uint8_t index = Entry.n_sect;
1889 
1890   if (index == 0)
1891     return section_end();
1892   DataRefImpl DRI;
1893   DRI.d.a = index - 1;
1894   if (DRI.d.a >= Sections.size()){
1895     return malformedError("bad section index: " + Twine((int)index) +
1896                           " for symbol at index " + Twine(getSymbolIndex(Symb)));
1897   }
1898   return section_iterator(SectionRef(DRI, this));
1899 }
1900 
1901 unsigned MachOObjectFile::getSymbolSectionID(SymbolRef Sym) const {
1902   MachO::nlist_base Entry =
1903       getSymbolTableEntryBase(*this, Sym.getRawDataRefImpl());
1904   return Entry.n_sect - 1;
1905 }
1906 
1907 void MachOObjectFile::moveSectionNext(DataRefImpl &Sec) const {
1908   Sec.d.a++;
1909 }
1910 
1911 Expected<StringRef> MachOObjectFile::getSectionName(DataRefImpl Sec) const {
1912   ArrayRef<char> Raw = getSectionRawName(Sec);
1913   return parseSegmentOrSectionName(Raw.data());
1914 }
1915 
1916 uint64_t MachOObjectFile::getSectionAddress(DataRefImpl Sec) const {
1917   if (is64Bit())
1918     return getSection64(Sec).addr;
1919   return getSection(Sec).addr;
1920 }
1921 
1922 uint64_t MachOObjectFile::getSectionIndex(DataRefImpl Sec) const {
1923   return Sec.d.a;
1924 }
1925 
1926 uint64_t MachOObjectFile::getSectionSize(DataRefImpl Sec) const {
1927   // In the case if a malformed Mach-O file where the section offset is past
1928   // the end of the file or some part of the section size is past the end of
1929   // the file return a size of zero or a size that covers the rest of the file
1930   // but does not extend past the end of the file.
1931   uint32_t SectOffset, SectType;
1932   uint64_t SectSize;
1933 
1934   if (is64Bit()) {
1935     MachO::section_64 Sect = getSection64(Sec);
1936     SectOffset = Sect.offset;
1937     SectSize = Sect.size;
1938     SectType = Sect.flags & MachO::SECTION_TYPE;
1939   } else {
1940     MachO::section Sect = getSection(Sec);
1941     SectOffset = Sect.offset;
1942     SectSize = Sect.size;
1943     SectType = Sect.flags & MachO::SECTION_TYPE;
1944   }
1945   if (SectType == MachO::S_ZEROFILL || SectType == MachO::S_GB_ZEROFILL)
1946     return SectSize;
1947   uint64_t FileSize = getData().size();
1948   if (SectOffset > FileSize)
1949     return 0;
1950   if (FileSize - SectOffset < SectSize)
1951     return FileSize - SectOffset;
1952   return SectSize;
1953 }
1954 
1955 ArrayRef<uint8_t> MachOObjectFile::getSectionContents(uint32_t Offset,
1956                                                       uint64_t Size) const {
1957   return arrayRefFromStringRef(getData().substr(Offset, Size));
1958 }
1959 
1960 Expected<ArrayRef<uint8_t>>
1961 MachOObjectFile::getSectionContents(DataRefImpl Sec) const {
1962   uint32_t Offset;
1963   uint64_t Size;
1964 
1965   if (is64Bit()) {
1966     MachO::section_64 Sect = getSection64(Sec);
1967     Offset = Sect.offset;
1968     Size = Sect.size;
1969   } else {
1970     MachO::section Sect = getSection(Sec);
1971     Offset = Sect.offset;
1972     Size = Sect.size;
1973   }
1974 
1975   return getSectionContents(Offset, Size);
1976 }
1977 
1978 uint64_t MachOObjectFile::getSectionAlignment(DataRefImpl Sec) const {
1979   uint32_t Align;
1980   if (is64Bit()) {
1981     MachO::section_64 Sect = getSection64(Sec);
1982     Align = Sect.align;
1983   } else {
1984     MachO::section Sect = getSection(Sec);
1985     Align = Sect.align;
1986   }
1987 
1988   return uint64_t(1) << Align;
1989 }
1990 
1991 Expected<SectionRef> MachOObjectFile::getSection(unsigned SectionIndex) const {
1992   if (SectionIndex < 1 || SectionIndex > Sections.size())
1993     return malformedError("bad section index: " + Twine((int)SectionIndex));
1994 
1995   DataRefImpl DRI;
1996   DRI.d.a = SectionIndex - 1;
1997   return SectionRef(DRI, this);
1998 }
1999 
2000 Expected<SectionRef> MachOObjectFile::getSection(StringRef SectionName) const {
2001   for (const SectionRef &Section : sections()) {
2002     auto NameOrErr = Section.getName();
2003     if (!NameOrErr)
2004       return NameOrErr.takeError();
2005     if (*NameOrErr == SectionName)
2006       return Section;
2007   }
2008   return errorCodeToError(object_error::parse_failed);
2009 }
2010 
2011 bool MachOObjectFile::isSectionCompressed(DataRefImpl Sec) const {
2012   return false;
2013 }
2014 
2015 bool MachOObjectFile::isSectionText(DataRefImpl Sec) const {
2016   uint32_t Flags = getSectionFlags(*this, Sec);
2017   return Flags & MachO::S_ATTR_PURE_INSTRUCTIONS;
2018 }
2019 
2020 bool MachOObjectFile::isSectionData(DataRefImpl Sec) const {
2021   uint32_t Flags = getSectionFlags(*this, Sec);
2022   unsigned SectionType = Flags & MachO::SECTION_TYPE;
2023   return !(Flags & MachO::S_ATTR_PURE_INSTRUCTIONS) &&
2024          !(SectionType == MachO::S_ZEROFILL ||
2025            SectionType == MachO::S_GB_ZEROFILL);
2026 }
2027 
2028 bool MachOObjectFile::isSectionBSS(DataRefImpl Sec) const {
2029   uint32_t Flags = getSectionFlags(*this, Sec);
2030   unsigned SectionType = Flags & MachO::SECTION_TYPE;
2031   return !(Flags & MachO::S_ATTR_PURE_INSTRUCTIONS) &&
2032          (SectionType == MachO::S_ZEROFILL ||
2033           SectionType == MachO::S_GB_ZEROFILL);
2034 }
2035 
2036 bool MachOObjectFile::isDebugSection(StringRef SectionName) const {
2037   return SectionName.startswith("__debug") ||
2038          SectionName.startswith("__zdebug") ||
2039          SectionName.startswith("__apple") || SectionName == "__gdb_index" ||
2040          SectionName == "__swift_ast";
2041 }
2042 
2043 unsigned MachOObjectFile::getSectionID(SectionRef Sec) const {
2044   return Sec.getRawDataRefImpl().d.a;
2045 }
2046 
2047 bool MachOObjectFile::isSectionVirtual(DataRefImpl Sec) const {
2048   uint32_t Flags = getSectionFlags(*this, Sec);
2049   unsigned SectionType = Flags & MachO::SECTION_TYPE;
2050   return SectionType == MachO::S_ZEROFILL ||
2051          SectionType == MachO::S_GB_ZEROFILL;
2052 }
2053 
2054 bool MachOObjectFile::isSectionBitcode(DataRefImpl Sec) const {
2055   StringRef SegmentName = getSectionFinalSegmentName(Sec);
2056   if (Expected<StringRef> NameOrErr = getSectionName(Sec))
2057     return (SegmentName == "__LLVM" && *NameOrErr == "__bitcode");
2058   return false;
2059 }
2060 
2061 bool MachOObjectFile::isSectionStripped(DataRefImpl Sec) const {
2062   if (is64Bit())
2063     return getSection64(Sec).offset == 0;
2064   return getSection(Sec).offset == 0;
2065 }
2066 
2067 relocation_iterator MachOObjectFile::section_rel_begin(DataRefImpl Sec) const {
2068   DataRefImpl Ret;
2069   Ret.d.a = Sec.d.a;
2070   Ret.d.b = 0;
2071   return relocation_iterator(RelocationRef(Ret, this));
2072 }
2073 
2074 relocation_iterator
2075 MachOObjectFile::section_rel_end(DataRefImpl Sec) const {
2076   uint32_t Num;
2077   if (is64Bit()) {
2078     MachO::section_64 Sect = getSection64(Sec);
2079     Num = Sect.nreloc;
2080   } else {
2081     MachO::section Sect = getSection(Sec);
2082     Num = Sect.nreloc;
2083   }
2084 
2085   DataRefImpl Ret;
2086   Ret.d.a = Sec.d.a;
2087   Ret.d.b = Num;
2088   return relocation_iterator(RelocationRef(Ret, this));
2089 }
2090 
2091 relocation_iterator MachOObjectFile::extrel_begin() const {
2092   DataRefImpl Ret;
2093   // for DYSYMTAB symbols, Ret.d.a == 0 for external relocations
2094   Ret.d.a = 0; // Would normally be a section index.
2095   Ret.d.b = 0; // Index into the external relocations
2096   return relocation_iterator(RelocationRef(Ret, this));
2097 }
2098 
2099 relocation_iterator MachOObjectFile::extrel_end() const {
2100   MachO::dysymtab_command DysymtabLoadCmd = getDysymtabLoadCommand();
2101   DataRefImpl Ret;
2102   // for DYSYMTAB symbols, Ret.d.a == 0 for external relocations
2103   Ret.d.a = 0; // Would normally be a section index.
2104   Ret.d.b = DysymtabLoadCmd.nextrel; // Index into the external relocations
2105   return relocation_iterator(RelocationRef(Ret, this));
2106 }
2107 
2108 relocation_iterator MachOObjectFile::locrel_begin() const {
2109   DataRefImpl Ret;
2110   // for DYSYMTAB symbols, Ret.d.a == 1 for local relocations
2111   Ret.d.a = 1; // Would normally be a section index.
2112   Ret.d.b = 0; // Index into the local relocations
2113   return relocation_iterator(RelocationRef(Ret, this));
2114 }
2115 
2116 relocation_iterator MachOObjectFile::locrel_end() const {
2117   MachO::dysymtab_command DysymtabLoadCmd = getDysymtabLoadCommand();
2118   DataRefImpl Ret;
2119   // for DYSYMTAB symbols, Ret.d.a == 1 for local relocations
2120   Ret.d.a = 1; // Would normally be a section index.
2121   Ret.d.b = DysymtabLoadCmd.nlocrel; // Index into the local relocations
2122   return relocation_iterator(RelocationRef(Ret, this));
2123 }
2124 
2125 void MachOObjectFile::moveRelocationNext(DataRefImpl &Rel) const {
2126   ++Rel.d.b;
2127 }
2128 
2129 uint64_t MachOObjectFile::getRelocationOffset(DataRefImpl Rel) const {
2130   assert((getHeader().filetype == MachO::MH_OBJECT ||
2131           getHeader().filetype == MachO::MH_KEXT_BUNDLE) &&
2132          "Only implemented for MH_OBJECT && MH_KEXT_BUNDLE");
2133   MachO::any_relocation_info RE = getRelocation(Rel);
2134   return getAnyRelocationAddress(RE);
2135 }
2136 
2137 symbol_iterator
2138 MachOObjectFile::getRelocationSymbol(DataRefImpl Rel) const {
2139   MachO::any_relocation_info RE = getRelocation(Rel);
2140   if (isRelocationScattered(RE))
2141     return symbol_end();
2142 
2143   uint32_t SymbolIdx = getPlainRelocationSymbolNum(RE);
2144   bool isExtern = getPlainRelocationExternal(RE);
2145   if (!isExtern)
2146     return symbol_end();
2147 
2148   MachO::symtab_command S = getSymtabLoadCommand();
2149   unsigned SymbolTableEntrySize = is64Bit() ?
2150     sizeof(MachO::nlist_64) :
2151     sizeof(MachO::nlist);
2152   uint64_t Offset = S.symoff + SymbolIdx * SymbolTableEntrySize;
2153   DataRefImpl Sym;
2154   Sym.p = reinterpret_cast<uintptr_t>(getPtr(*this, Offset));
2155   return symbol_iterator(SymbolRef(Sym, this));
2156 }
2157 
2158 section_iterator
2159 MachOObjectFile::getRelocationSection(DataRefImpl Rel) const {
2160   return section_iterator(getAnyRelocationSection(getRelocation(Rel)));
2161 }
2162 
2163 uint64_t MachOObjectFile::getRelocationType(DataRefImpl Rel) const {
2164   MachO::any_relocation_info RE = getRelocation(Rel);
2165   return getAnyRelocationType(RE);
2166 }
2167 
2168 void MachOObjectFile::getRelocationTypeName(
2169     DataRefImpl Rel, SmallVectorImpl<char> &Result) const {
2170   StringRef res;
2171   uint64_t RType = getRelocationType(Rel);
2172 
2173   unsigned Arch = this->getArch();
2174 
2175   switch (Arch) {
2176     case Triple::x86: {
2177       static const char *const Table[] =  {
2178         "GENERIC_RELOC_VANILLA",
2179         "GENERIC_RELOC_PAIR",
2180         "GENERIC_RELOC_SECTDIFF",
2181         "GENERIC_RELOC_PB_LA_PTR",
2182         "GENERIC_RELOC_LOCAL_SECTDIFF",
2183         "GENERIC_RELOC_TLV" };
2184 
2185       if (RType > 5)
2186         res = "Unknown";
2187       else
2188         res = Table[RType];
2189       break;
2190     }
2191     case Triple::x86_64: {
2192       static const char *const Table[] =  {
2193         "X86_64_RELOC_UNSIGNED",
2194         "X86_64_RELOC_SIGNED",
2195         "X86_64_RELOC_BRANCH",
2196         "X86_64_RELOC_GOT_LOAD",
2197         "X86_64_RELOC_GOT",
2198         "X86_64_RELOC_SUBTRACTOR",
2199         "X86_64_RELOC_SIGNED_1",
2200         "X86_64_RELOC_SIGNED_2",
2201         "X86_64_RELOC_SIGNED_4",
2202         "X86_64_RELOC_TLV" };
2203 
2204       if (RType > 9)
2205         res = "Unknown";
2206       else
2207         res = Table[RType];
2208       break;
2209     }
2210     case Triple::arm: {
2211       static const char *const Table[] =  {
2212         "ARM_RELOC_VANILLA",
2213         "ARM_RELOC_PAIR",
2214         "ARM_RELOC_SECTDIFF",
2215         "ARM_RELOC_LOCAL_SECTDIFF",
2216         "ARM_RELOC_PB_LA_PTR",
2217         "ARM_RELOC_BR24",
2218         "ARM_THUMB_RELOC_BR22",
2219         "ARM_THUMB_32BIT_BRANCH",
2220         "ARM_RELOC_HALF",
2221         "ARM_RELOC_HALF_SECTDIFF" };
2222 
2223       if (RType > 9)
2224         res = "Unknown";
2225       else
2226         res = Table[RType];
2227       break;
2228     }
2229     case Triple::aarch64:
2230     case Triple::aarch64_32: {
2231       static const char *const Table[] = {
2232         "ARM64_RELOC_UNSIGNED",           "ARM64_RELOC_SUBTRACTOR",
2233         "ARM64_RELOC_BRANCH26",           "ARM64_RELOC_PAGE21",
2234         "ARM64_RELOC_PAGEOFF12",          "ARM64_RELOC_GOT_LOAD_PAGE21",
2235         "ARM64_RELOC_GOT_LOAD_PAGEOFF12", "ARM64_RELOC_POINTER_TO_GOT",
2236         "ARM64_RELOC_TLVP_LOAD_PAGE21",   "ARM64_RELOC_TLVP_LOAD_PAGEOFF12",
2237         "ARM64_RELOC_ADDEND"
2238       };
2239 
2240       if (RType >= array_lengthof(Table))
2241         res = "Unknown";
2242       else
2243         res = Table[RType];
2244       break;
2245     }
2246     case Triple::ppc: {
2247       static const char *const Table[] =  {
2248         "PPC_RELOC_VANILLA",
2249         "PPC_RELOC_PAIR",
2250         "PPC_RELOC_BR14",
2251         "PPC_RELOC_BR24",
2252         "PPC_RELOC_HI16",
2253         "PPC_RELOC_LO16",
2254         "PPC_RELOC_HA16",
2255         "PPC_RELOC_LO14",
2256         "PPC_RELOC_SECTDIFF",
2257         "PPC_RELOC_PB_LA_PTR",
2258         "PPC_RELOC_HI16_SECTDIFF",
2259         "PPC_RELOC_LO16_SECTDIFF",
2260         "PPC_RELOC_HA16_SECTDIFF",
2261         "PPC_RELOC_JBSR",
2262         "PPC_RELOC_LO14_SECTDIFF",
2263         "PPC_RELOC_LOCAL_SECTDIFF" };
2264 
2265       if (RType > 15)
2266         res = "Unknown";
2267       else
2268         res = Table[RType];
2269       break;
2270     }
2271     case Triple::UnknownArch:
2272       res = "Unknown";
2273       break;
2274   }
2275   Result.append(res.begin(), res.end());
2276 }
2277 
2278 uint8_t MachOObjectFile::getRelocationLength(DataRefImpl Rel) const {
2279   MachO::any_relocation_info RE = getRelocation(Rel);
2280   return getAnyRelocationLength(RE);
2281 }
2282 
2283 //
2284 // guessLibraryShortName() is passed a name of a dynamic library and returns a
2285 // guess on what the short name is.  Then name is returned as a substring of the
2286 // StringRef Name passed in.  The name of the dynamic library is recognized as
2287 // a framework if it has one of the two following forms:
2288 //      Foo.framework/Versions/A/Foo
2289 //      Foo.framework/Foo
2290 // Where A and Foo can be any string.  And may contain a trailing suffix
2291 // starting with an underbar.  If the Name is recognized as a framework then
2292 // isFramework is set to true else it is set to false.  If the Name has a
2293 // suffix then Suffix is set to the substring in Name that contains the suffix
2294 // else it is set to a NULL StringRef.
2295 //
2296 // The Name of the dynamic library is recognized as a library name if it has
2297 // one of the two following forms:
2298 //      libFoo.A.dylib
2299 //      libFoo.dylib
2300 //
2301 // The library may have a suffix trailing the name Foo of the form:
2302 //      libFoo_profile.A.dylib
2303 //      libFoo_profile.dylib
2304 // These dyld image suffixes are separated from the short name by a '_'
2305 // character. Because the '_' character is commonly used to separate words in
2306 // filenames guessLibraryShortName() cannot reliably separate a dylib's short
2307 // name from an arbitrary image suffix; imagine if both the short name and the
2308 // suffix contains an '_' character! To better deal with this ambiguity,
2309 // guessLibraryShortName() will recognize only "_debug" and "_profile" as valid
2310 // Suffix values. Calling code needs to be tolerant of guessLibraryShortName()
2311 // guessing incorrectly.
2312 //
2313 // The Name of the dynamic library is also recognized as a library name if it
2314 // has the following form:
2315 //      Foo.qtx
2316 //
2317 // If the Name of the dynamic library is none of the forms above then a NULL
2318 // StringRef is returned.
2319 StringRef MachOObjectFile::guessLibraryShortName(StringRef Name,
2320                                                  bool &isFramework,
2321                                                  StringRef &Suffix) {
2322   StringRef Foo, F, DotFramework, V, Dylib, Lib, Dot, Qtx;
2323   size_t a, b, c, d, Idx;
2324 
2325   isFramework = false;
2326   Suffix = StringRef();
2327 
2328   // Pull off the last component and make Foo point to it
2329   a = Name.rfind('/');
2330   if (a == Name.npos || a == 0)
2331     goto guess_library;
2332   Foo = Name.slice(a+1, Name.npos);
2333 
2334   // Look for a suffix starting with a '_'
2335   Idx = Foo.rfind('_');
2336   if (Idx != Foo.npos && Foo.size() >= 2) {
2337     Suffix = Foo.slice(Idx, Foo.npos);
2338     if (Suffix != "_debug" && Suffix != "_profile")
2339       Suffix = StringRef();
2340     else
2341       Foo = Foo.slice(0, Idx);
2342   }
2343 
2344   // First look for the form Foo.framework/Foo
2345   b = Name.rfind('/', a);
2346   if (b == Name.npos)
2347     Idx = 0;
2348   else
2349     Idx = b+1;
2350   F = Name.slice(Idx, Idx + Foo.size());
2351   DotFramework = Name.slice(Idx + Foo.size(),
2352                             Idx + Foo.size() + sizeof(".framework/")-1);
2353   if (F == Foo && DotFramework == ".framework/") {
2354     isFramework = true;
2355     return Foo;
2356   }
2357 
2358   // Next look for the form Foo.framework/Versions/A/Foo
2359   if (b == Name.npos)
2360     goto guess_library;
2361   c =  Name.rfind('/', b);
2362   if (c == Name.npos || c == 0)
2363     goto guess_library;
2364   V = Name.slice(c+1, Name.npos);
2365   if (!V.startswith("Versions/"))
2366     goto guess_library;
2367   d =  Name.rfind('/', c);
2368   if (d == Name.npos)
2369     Idx = 0;
2370   else
2371     Idx = d+1;
2372   F = Name.slice(Idx, Idx + Foo.size());
2373   DotFramework = Name.slice(Idx + Foo.size(),
2374                             Idx + Foo.size() + sizeof(".framework/")-1);
2375   if (F == Foo && DotFramework == ".framework/") {
2376     isFramework = true;
2377     return Foo;
2378   }
2379 
2380 guess_library:
2381   // pull off the suffix after the "." and make a point to it
2382   a = Name.rfind('.');
2383   if (a == Name.npos || a == 0)
2384     return StringRef();
2385   Dylib = Name.slice(a, Name.npos);
2386   if (Dylib != ".dylib")
2387     goto guess_qtx;
2388 
2389   // First pull off the version letter for the form Foo.A.dylib if any.
2390   if (a >= 3) {
2391     Dot = Name.slice(a-2, a-1);
2392     if (Dot == ".")
2393       a = a - 2;
2394   }
2395 
2396   b = Name.rfind('/', a);
2397   if (b == Name.npos)
2398     b = 0;
2399   else
2400     b = b+1;
2401   // ignore any suffix after an underbar like Foo_profile.A.dylib
2402   Idx = Name.rfind('_');
2403   if (Idx != Name.npos && Idx != b) {
2404     Lib = Name.slice(b, Idx);
2405     Suffix = Name.slice(Idx, a);
2406     if (Suffix != "_debug" && Suffix != "_profile") {
2407       Suffix = StringRef();
2408       Lib = Name.slice(b, a);
2409     }
2410   }
2411   else
2412     Lib = Name.slice(b, a);
2413   // There are incorrect library names of the form:
2414   // libATS.A_profile.dylib so check for these.
2415   if (Lib.size() >= 3) {
2416     Dot = Lib.slice(Lib.size()-2, Lib.size()-1);
2417     if (Dot == ".")
2418       Lib = Lib.slice(0, Lib.size()-2);
2419   }
2420   return Lib;
2421 
2422 guess_qtx:
2423   Qtx = Name.slice(a, Name.npos);
2424   if (Qtx != ".qtx")
2425     return StringRef();
2426   b = Name.rfind('/', a);
2427   if (b == Name.npos)
2428     Lib = Name.slice(0, a);
2429   else
2430     Lib = Name.slice(b+1, a);
2431   // There are library names of the form: QT.A.qtx so check for these.
2432   if (Lib.size() >= 3) {
2433     Dot = Lib.slice(Lib.size()-2, Lib.size()-1);
2434     if (Dot == ".")
2435       Lib = Lib.slice(0, Lib.size()-2);
2436   }
2437   return Lib;
2438 }
2439 
2440 // getLibraryShortNameByIndex() is used to get the short name of the library
2441 // for an undefined symbol in a linked Mach-O binary that was linked with the
2442 // normal two-level namespace default (that is MH_TWOLEVEL in the header).
2443 // It is passed the index (0 - based) of the library as translated from
2444 // GET_LIBRARY_ORDINAL (1 - based).
2445 std::error_code MachOObjectFile::getLibraryShortNameByIndex(unsigned Index,
2446                                                          StringRef &Res) const {
2447   if (Index >= Libraries.size())
2448     return object_error::parse_failed;
2449 
2450   // If the cache of LibrariesShortNames is not built up do that first for
2451   // all the Libraries.
2452   if (LibrariesShortNames.size() == 0) {
2453     for (unsigned i = 0; i < Libraries.size(); i++) {
2454       auto CommandOrErr =
2455         getStructOrErr<MachO::dylib_command>(*this, Libraries[i]);
2456       if (!CommandOrErr)
2457         return object_error::parse_failed;
2458       MachO::dylib_command D = CommandOrErr.get();
2459       if (D.dylib.name >= D.cmdsize)
2460         return object_error::parse_failed;
2461       const char *P = (const char *)(Libraries[i]) + D.dylib.name;
2462       StringRef Name = StringRef(P);
2463       if (D.dylib.name+Name.size() >= D.cmdsize)
2464         return object_error::parse_failed;
2465       StringRef Suffix;
2466       bool isFramework;
2467       StringRef shortName = guessLibraryShortName(Name, isFramework, Suffix);
2468       if (shortName.empty())
2469         LibrariesShortNames.push_back(Name);
2470       else
2471         LibrariesShortNames.push_back(shortName);
2472     }
2473   }
2474 
2475   Res = LibrariesShortNames[Index];
2476   return std::error_code();
2477 }
2478 
2479 uint32_t MachOObjectFile::getLibraryCount() const {
2480   return Libraries.size();
2481 }
2482 
2483 section_iterator
2484 MachOObjectFile::getRelocationRelocatedSection(relocation_iterator Rel) const {
2485   DataRefImpl Sec;
2486   Sec.d.a = Rel->getRawDataRefImpl().d.a;
2487   return section_iterator(SectionRef(Sec, this));
2488 }
2489 
2490 basic_symbol_iterator MachOObjectFile::symbol_begin() const {
2491   DataRefImpl DRI;
2492   MachO::symtab_command Symtab = getSymtabLoadCommand();
2493   if (!SymtabLoadCmd || Symtab.nsyms == 0)
2494     return basic_symbol_iterator(SymbolRef(DRI, this));
2495 
2496   return getSymbolByIndex(0);
2497 }
2498 
2499 basic_symbol_iterator MachOObjectFile::symbol_end() const {
2500   DataRefImpl DRI;
2501   MachO::symtab_command Symtab = getSymtabLoadCommand();
2502   if (!SymtabLoadCmd || Symtab.nsyms == 0)
2503     return basic_symbol_iterator(SymbolRef(DRI, this));
2504 
2505   unsigned SymbolTableEntrySize = is64Bit() ?
2506     sizeof(MachO::nlist_64) :
2507     sizeof(MachO::nlist);
2508   unsigned Offset = Symtab.symoff +
2509     Symtab.nsyms * SymbolTableEntrySize;
2510   DRI.p = reinterpret_cast<uintptr_t>(getPtr(*this, Offset));
2511   return basic_symbol_iterator(SymbolRef(DRI, this));
2512 }
2513 
2514 symbol_iterator MachOObjectFile::getSymbolByIndex(unsigned Index) const {
2515   MachO::symtab_command Symtab = getSymtabLoadCommand();
2516   if (!SymtabLoadCmd || Index >= Symtab.nsyms)
2517     report_fatal_error("Requested symbol index is out of range.");
2518   unsigned SymbolTableEntrySize =
2519     is64Bit() ? sizeof(MachO::nlist_64) : sizeof(MachO::nlist);
2520   DataRefImpl DRI;
2521   DRI.p = reinterpret_cast<uintptr_t>(getPtr(*this, Symtab.symoff));
2522   DRI.p += Index * SymbolTableEntrySize;
2523   return basic_symbol_iterator(SymbolRef(DRI, this));
2524 }
2525 
2526 uint64_t MachOObjectFile::getSymbolIndex(DataRefImpl Symb) const {
2527   MachO::symtab_command Symtab = getSymtabLoadCommand();
2528   if (!SymtabLoadCmd)
2529     report_fatal_error("getSymbolIndex() called with no symbol table symbol");
2530   unsigned SymbolTableEntrySize =
2531     is64Bit() ? sizeof(MachO::nlist_64) : sizeof(MachO::nlist);
2532   DataRefImpl DRIstart;
2533   DRIstart.p = reinterpret_cast<uintptr_t>(getPtr(*this, Symtab.symoff));
2534   uint64_t Index = (Symb.p - DRIstart.p) / SymbolTableEntrySize;
2535   return Index;
2536 }
2537 
2538 section_iterator MachOObjectFile::section_begin() const {
2539   DataRefImpl DRI;
2540   return section_iterator(SectionRef(DRI, this));
2541 }
2542 
2543 section_iterator MachOObjectFile::section_end() const {
2544   DataRefImpl DRI;
2545   DRI.d.a = Sections.size();
2546   return section_iterator(SectionRef(DRI, this));
2547 }
2548 
2549 uint8_t MachOObjectFile::getBytesInAddress() const {
2550   return is64Bit() ? 8 : 4;
2551 }
2552 
2553 StringRef MachOObjectFile::getFileFormatName() const {
2554   unsigned CPUType = getCPUType(*this);
2555   if (!is64Bit()) {
2556     switch (CPUType) {
2557     case MachO::CPU_TYPE_I386:
2558       return "Mach-O 32-bit i386";
2559     case MachO::CPU_TYPE_ARM:
2560       return "Mach-O arm";
2561     case MachO::CPU_TYPE_ARM64_32:
2562       return "Mach-O arm64 (ILP32)";
2563     case MachO::CPU_TYPE_POWERPC:
2564       return "Mach-O 32-bit ppc";
2565     default:
2566       return "Mach-O 32-bit unknown";
2567     }
2568   }
2569 
2570   switch (CPUType) {
2571   case MachO::CPU_TYPE_X86_64:
2572     return "Mach-O 64-bit x86-64";
2573   case MachO::CPU_TYPE_ARM64:
2574     return "Mach-O arm64";
2575   case MachO::CPU_TYPE_POWERPC64:
2576     return "Mach-O 64-bit ppc64";
2577   default:
2578     return "Mach-O 64-bit unknown";
2579   }
2580 }
2581 
2582 Triple::ArchType MachOObjectFile::getArch(uint32_t CPUType, uint32_t CPUSubType) {
2583   switch (CPUType) {
2584   case MachO::CPU_TYPE_I386:
2585     return Triple::x86;
2586   case MachO::CPU_TYPE_X86_64:
2587     return Triple::x86_64;
2588   case MachO::CPU_TYPE_ARM:
2589     return Triple::arm;
2590   case MachO::CPU_TYPE_ARM64:
2591     return Triple::aarch64;
2592   case MachO::CPU_TYPE_ARM64_32:
2593     return Triple::aarch64_32;
2594   case MachO::CPU_TYPE_POWERPC:
2595     return Triple::ppc;
2596   case MachO::CPU_TYPE_POWERPC64:
2597     return Triple::ppc64;
2598   default:
2599     return Triple::UnknownArch;
2600   }
2601 }
2602 
2603 Triple MachOObjectFile::getArchTriple(uint32_t CPUType, uint32_t CPUSubType,
2604                                       const char **McpuDefault,
2605                                       const char **ArchFlag) {
2606   if (McpuDefault)
2607     *McpuDefault = nullptr;
2608   if (ArchFlag)
2609     *ArchFlag = nullptr;
2610 
2611   switch (CPUType) {
2612   case MachO::CPU_TYPE_I386:
2613     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
2614     case MachO::CPU_SUBTYPE_I386_ALL:
2615       if (ArchFlag)
2616         *ArchFlag = "i386";
2617       return Triple("i386-apple-darwin");
2618     default:
2619       return Triple();
2620     }
2621   case MachO::CPU_TYPE_X86_64:
2622     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
2623     case MachO::CPU_SUBTYPE_X86_64_ALL:
2624       if (ArchFlag)
2625         *ArchFlag = "x86_64";
2626       return Triple("x86_64-apple-darwin");
2627     case MachO::CPU_SUBTYPE_X86_64_H:
2628       if (ArchFlag)
2629         *ArchFlag = "x86_64h";
2630       return Triple("x86_64h-apple-darwin");
2631     default:
2632       return Triple();
2633     }
2634   case MachO::CPU_TYPE_ARM:
2635     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
2636     case MachO::CPU_SUBTYPE_ARM_V4T:
2637       if (ArchFlag)
2638         *ArchFlag = "armv4t";
2639       return Triple("armv4t-apple-darwin");
2640     case MachO::CPU_SUBTYPE_ARM_V5TEJ:
2641       if (ArchFlag)
2642         *ArchFlag = "armv5e";
2643       return Triple("armv5e-apple-darwin");
2644     case MachO::CPU_SUBTYPE_ARM_XSCALE:
2645       if (ArchFlag)
2646         *ArchFlag = "xscale";
2647       return Triple("xscale-apple-darwin");
2648     case MachO::CPU_SUBTYPE_ARM_V6:
2649       if (ArchFlag)
2650         *ArchFlag = "armv6";
2651       return Triple("armv6-apple-darwin");
2652     case MachO::CPU_SUBTYPE_ARM_V6M:
2653       if (McpuDefault)
2654         *McpuDefault = "cortex-m0";
2655       if (ArchFlag)
2656         *ArchFlag = "armv6m";
2657       return Triple("armv6m-apple-darwin");
2658     case MachO::CPU_SUBTYPE_ARM_V7:
2659       if (ArchFlag)
2660         *ArchFlag = "armv7";
2661       return Triple("armv7-apple-darwin");
2662     case MachO::CPU_SUBTYPE_ARM_V7EM:
2663       if (McpuDefault)
2664         *McpuDefault = "cortex-m4";
2665       if (ArchFlag)
2666         *ArchFlag = "armv7em";
2667       return Triple("thumbv7em-apple-darwin");
2668     case MachO::CPU_SUBTYPE_ARM_V7K:
2669       if (McpuDefault)
2670         *McpuDefault = "cortex-a7";
2671       if (ArchFlag)
2672         *ArchFlag = "armv7k";
2673       return Triple("armv7k-apple-darwin");
2674     case MachO::CPU_SUBTYPE_ARM_V7M:
2675       if (McpuDefault)
2676         *McpuDefault = "cortex-m3";
2677       if (ArchFlag)
2678         *ArchFlag = "armv7m";
2679       return Triple("thumbv7m-apple-darwin");
2680     case MachO::CPU_SUBTYPE_ARM_V7S:
2681       if (McpuDefault)
2682         *McpuDefault = "cortex-a7";
2683       if (ArchFlag)
2684         *ArchFlag = "armv7s";
2685       return Triple("armv7s-apple-darwin");
2686     default:
2687       return Triple();
2688     }
2689   case MachO::CPU_TYPE_ARM64:
2690     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
2691     case MachO::CPU_SUBTYPE_ARM64_ALL:
2692       if (McpuDefault)
2693         *McpuDefault = "cyclone";
2694       if (ArchFlag)
2695         *ArchFlag = "arm64";
2696       return Triple("arm64-apple-darwin");
2697     default:
2698       return Triple();
2699     }
2700   case MachO::CPU_TYPE_ARM64_32:
2701     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
2702     case MachO::CPU_SUBTYPE_ARM64_32_V8:
2703       if (McpuDefault)
2704         *McpuDefault = "cyclone";
2705       if (ArchFlag)
2706         *ArchFlag = "arm64_32";
2707       return Triple("arm64_32-apple-darwin");
2708     default:
2709       return Triple();
2710     }
2711   case MachO::CPU_TYPE_POWERPC:
2712     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
2713     case MachO::CPU_SUBTYPE_POWERPC_ALL:
2714       if (ArchFlag)
2715         *ArchFlag = "ppc";
2716       return Triple("ppc-apple-darwin");
2717     default:
2718       return Triple();
2719     }
2720   case MachO::CPU_TYPE_POWERPC64:
2721     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
2722     case MachO::CPU_SUBTYPE_POWERPC_ALL:
2723       if (ArchFlag)
2724         *ArchFlag = "ppc64";
2725       return Triple("ppc64-apple-darwin");
2726     default:
2727       return Triple();
2728     }
2729   default:
2730     return Triple();
2731   }
2732 }
2733 
2734 Triple MachOObjectFile::getHostArch() {
2735   return Triple(sys::getDefaultTargetTriple());
2736 }
2737 
2738 bool MachOObjectFile::isValidArch(StringRef ArchFlag) {
2739   auto validArchs = getValidArchs();
2740   return llvm::find(validArchs, ArchFlag) != validArchs.end();
2741 }
2742 
2743 ArrayRef<StringRef> MachOObjectFile::getValidArchs() {
2744   static const std::array<StringRef, 17> validArchs = {{
2745       "i386",   "x86_64", "x86_64h",  "armv4t",  "arm",    "armv5e",
2746       "armv6",  "armv6m", "armv7",    "armv7em", "armv7k", "armv7m",
2747       "armv7s", "arm64",  "arm64_32", "ppc",     "ppc64",
2748   }};
2749 
2750   return validArchs;
2751 }
2752 
2753 Triple::ArchType MachOObjectFile::getArch() const {
2754   return getArch(getCPUType(*this), getCPUSubType(*this));
2755 }
2756 
2757 Triple MachOObjectFile::getArchTriple(const char **McpuDefault) const {
2758   return getArchTriple(Header.cputype, Header.cpusubtype, McpuDefault);
2759 }
2760 
2761 relocation_iterator MachOObjectFile::section_rel_begin(unsigned Index) const {
2762   DataRefImpl DRI;
2763   DRI.d.a = Index;
2764   return section_rel_begin(DRI);
2765 }
2766 
2767 relocation_iterator MachOObjectFile::section_rel_end(unsigned Index) const {
2768   DataRefImpl DRI;
2769   DRI.d.a = Index;
2770   return section_rel_end(DRI);
2771 }
2772 
2773 dice_iterator MachOObjectFile::begin_dices() const {
2774   DataRefImpl DRI;
2775   if (!DataInCodeLoadCmd)
2776     return dice_iterator(DiceRef(DRI, this));
2777 
2778   MachO::linkedit_data_command DicLC = getDataInCodeLoadCommand();
2779   DRI.p = reinterpret_cast<uintptr_t>(getPtr(*this, DicLC.dataoff));
2780   return dice_iterator(DiceRef(DRI, this));
2781 }
2782 
2783 dice_iterator MachOObjectFile::end_dices() const {
2784   DataRefImpl DRI;
2785   if (!DataInCodeLoadCmd)
2786     return dice_iterator(DiceRef(DRI, this));
2787 
2788   MachO::linkedit_data_command DicLC = getDataInCodeLoadCommand();
2789   unsigned Offset = DicLC.dataoff + DicLC.datasize;
2790   DRI.p = reinterpret_cast<uintptr_t>(getPtr(*this, Offset));
2791   return dice_iterator(DiceRef(DRI, this));
2792 }
2793 
2794 ExportEntry::ExportEntry(Error *E, const MachOObjectFile *O,
2795                          ArrayRef<uint8_t> T) : E(E), O(O), Trie(T) {}
2796 
2797 void ExportEntry::moveToFirst() {
2798   ErrorAsOutParameter ErrAsOutParam(E);
2799   pushNode(0);
2800   if (*E)
2801     return;
2802   pushDownUntilBottom();
2803 }
2804 
2805 void ExportEntry::moveToEnd() {
2806   Stack.clear();
2807   Done = true;
2808 }
2809 
2810 bool ExportEntry::operator==(const ExportEntry &Other) const {
2811   // Common case, one at end, other iterating from begin.
2812   if (Done || Other.Done)
2813     return (Done == Other.Done);
2814   // Not equal if different stack sizes.
2815   if (Stack.size() != Other.Stack.size())
2816     return false;
2817   // Not equal if different cumulative strings.
2818   if (!CumulativeString.equals(Other.CumulativeString))
2819     return false;
2820   // Equal if all nodes in both stacks match.
2821   for (unsigned i=0; i < Stack.size(); ++i) {
2822     if (Stack[i].Start != Other.Stack[i].Start)
2823       return false;
2824   }
2825   return true;
2826 }
2827 
2828 uint64_t ExportEntry::readULEB128(const uint8_t *&Ptr, const char **error) {
2829   unsigned Count;
2830   uint64_t Result = decodeULEB128(Ptr, &Count, Trie.end(), error);
2831   Ptr += Count;
2832   if (Ptr > Trie.end())
2833     Ptr = Trie.end();
2834   return Result;
2835 }
2836 
2837 StringRef ExportEntry::name() const {
2838   return CumulativeString;
2839 }
2840 
2841 uint64_t ExportEntry::flags() const {
2842   return Stack.back().Flags;
2843 }
2844 
2845 uint64_t ExportEntry::address() const {
2846   return Stack.back().Address;
2847 }
2848 
2849 uint64_t ExportEntry::other() const {
2850   return Stack.back().Other;
2851 }
2852 
2853 StringRef ExportEntry::otherName() const {
2854   const char* ImportName = Stack.back().ImportName;
2855   if (ImportName)
2856     return StringRef(ImportName);
2857   return StringRef();
2858 }
2859 
2860 uint32_t ExportEntry::nodeOffset() const {
2861   return Stack.back().Start - Trie.begin();
2862 }
2863 
2864 ExportEntry::NodeState::NodeState(const uint8_t *Ptr)
2865     : Start(Ptr), Current(Ptr) {}
2866 
2867 void ExportEntry::pushNode(uint64_t offset) {
2868   ErrorAsOutParameter ErrAsOutParam(E);
2869   const uint8_t *Ptr = Trie.begin() + offset;
2870   NodeState State(Ptr);
2871   const char *error;
2872   uint64_t ExportInfoSize = readULEB128(State.Current, &error);
2873   if (error) {
2874     *E = malformedError("export info size " + Twine(error) +
2875                         " in export trie data at node: 0x" +
2876                         Twine::utohexstr(offset));
2877     moveToEnd();
2878     return;
2879   }
2880   State.IsExportNode = (ExportInfoSize != 0);
2881   const uint8_t* Children = State.Current + ExportInfoSize;
2882   if (Children > Trie.end()) {
2883     *E = malformedError(
2884         "export info size: 0x" + Twine::utohexstr(ExportInfoSize) +
2885         " in export trie data at node: 0x" + Twine::utohexstr(offset) +
2886         " too big and extends past end of trie data");
2887     moveToEnd();
2888     return;
2889   }
2890   if (State.IsExportNode) {
2891     const uint8_t *ExportStart = State.Current;
2892     State.Flags = readULEB128(State.Current, &error);
2893     if (error) {
2894       *E = malformedError("flags " + Twine(error) +
2895                           " in export trie data at node: 0x" +
2896                           Twine::utohexstr(offset));
2897       moveToEnd();
2898       return;
2899     }
2900     uint64_t Kind = State.Flags & MachO::EXPORT_SYMBOL_FLAGS_KIND_MASK;
2901     if (State.Flags != 0 &&
2902         (Kind != MachO::EXPORT_SYMBOL_FLAGS_KIND_REGULAR &&
2903          Kind != MachO::EXPORT_SYMBOL_FLAGS_KIND_ABSOLUTE &&
2904          Kind != MachO::EXPORT_SYMBOL_FLAGS_KIND_THREAD_LOCAL)) {
2905       *E = malformedError(
2906           "unsupported exported symbol kind: " + Twine((int)Kind) +
2907           " in flags: 0x" + Twine::utohexstr(State.Flags) +
2908           " in export trie data at node: 0x" + Twine::utohexstr(offset));
2909       moveToEnd();
2910       return;
2911     }
2912     if (State.Flags & MachO::EXPORT_SYMBOL_FLAGS_REEXPORT) {
2913       State.Address = 0;
2914       State.Other = readULEB128(State.Current, &error); // dylib ordinal
2915       if (error) {
2916         *E = malformedError("dylib ordinal of re-export " + Twine(error) +
2917                             " in export trie data at node: 0x" +
2918                             Twine::utohexstr(offset));
2919         moveToEnd();
2920         return;
2921       }
2922       if (O != nullptr) {
2923         if (State.Other > O->getLibraryCount()) {
2924           *E = malformedError(
2925               "bad library ordinal: " + Twine((int)State.Other) + " (max " +
2926               Twine((int)O->getLibraryCount()) +
2927               ") in export trie data at node: 0x" + Twine::utohexstr(offset));
2928           moveToEnd();
2929           return;
2930         }
2931       }
2932       State.ImportName = reinterpret_cast<const char*>(State.Current);
2933       if (*State.ImportName == '\0') {
2934         State.Current++;
2935       } else {
2936         const uint8_t *End = State.Current + 1;
2937         if (End >= Trie.end()) {
2938           *E = malformedError("import name of re-export in export trie data at "
2939                               "node: 0x" +
2940                               Twine::utohexstr(offset) +
2941                               " starts past end of trie data");
2942           moveToEnd();
2943           return;
2944         }
2945         while(*End != '\0' && End < Trie.end())
2946           End++;
2947         if (*End != '\0') {
2948           *E = malformedError("import name of re-export in export trie data at "
2949                               "node: 0x" +
2950                               Twine::utohexstr(offset) +
2951                               " extends past end of trie data");
2952           moveToEnd();
2953           return;
2954         }
2955         State.Current = End + 1;
2956       }
2957     } else {
2958       State.Address = readULEB128(State.Current, &error);
2959       if (error) {
2960         *E = malformedError("address " + Twine(error) +
2961                             " in export trie data at node: 0x" +
2962                             Twine::utohexstr(offset));
2963         moveToEnd();
2964         return;
2965       }
2966       if (State.Flags & MachO::EXPORT_SYMBOL_FLAGS_STUB_AND_RESOLVER) {
2967         State.Other = readULEB128(State.Current, &error);
2968         if (error) {
2969           *E = malformedError("resolver of stub and resolver " + Twine(error) +
2970                               " in export trie data at node: 0x" +
2971                               Twine::utohexstr(offset));
2972           moveToEnd();
2973           return;
2974         }
2975       }
2976     }
2977     if(ExportStart + ExportInfoSize != State.Current) {
2978       *E = malformedError(
2979           "inconsistant export info size: 0x" +
2980           Twine::utohexstr(ExportInfoSize) + " where actual size was: 0x" +
2981           Twine::utohexstr(State.Current - ExportStart) +
2982           " in export trie data at node: 0x" + Twine::utohexstr(offset));
2983       moveToEnd();
2984       return;
2985     }
2986   }
2987   State.ChildCount = *Children;
2988   if (State.ChildCount != 0 && Children + 1 >= Trie.end()) {
2989     *E = malformedError("byte for count of childern in export trie data at "
2990                         "node: 0x" +
2991                         Twine::utohexstr(offset) +
2992                         " extends past end of trie data");
2993     moveToEnd();
2994     return;
2995   }
2996   State.Current = Children + 1;
2997   State.NextChildIndex = 0;
2998   State.ParentStringLength = CumulativeString.size();
2999   Stack.push_back(State);
3000 }
3001 
3002 void ExportEntry::pushDownUntilBottom() {
3003   ErrorAsOutParameter ErrAsOutParam(E);
3004   const char *error;
3005   while (Stack.back().NextChildIndex < Stack.back().ChildCount) {
3006     NodeState &Top = Stack.back();
3007     CumulativeString.resize(Top.ParentStringLength);
3008     for (;*Top.Current != 0 && Top.Current < Trie.end(); Top.Current++) {
3009       char C = *Top.Current;
3010       CumulativeString.push_back(C);
3011     }
3012     if (Top.Current >= Trie.end()) {
3013       *E = malformedError("edge sub-string in export trie data at node: 0x" +
3014                           Twine::utohexstr(Top.Start - Trie.begin()) +
3015                           " for child #" + Twine((int)Top.NextChildIndex) +
3016                           " extends past end of trie data");
3017       moveToEnd();
3018       return;
3019     }
3020     Top.Current += 1;
3021     uint64_t childNodeIndex = readULEB128(Top.Current, &error);
3022     if (error) {
3023       *E = malformedError("child node offset " + Twine(error) +
3024                           " in export trie data at node: 0x" +
3025                           Twine::utohexstr(Top.Start - Trie.begin()));
3026       moveToEnd();
3027       return;
3028     }
3029     for (const NodeState &node : nodes()) {
3030       if (node.Start == Trie.begin() + childNodeIndex){
3031         *E = malformedError("loop in childern in export trie data at node: 0x" +
3032                             Twine::utohexstr(Top.Start - Trie.begin()) +
3033                             " back to node: 0x" +
3034                             Twine::utohexstr(childNodeIndex));
3035         moveToEnd();
3036         return;
3037       }
3038     }
3039     Top.NextChildIndex += 1;
3040     pushNode(childNodeIndex);
3041     if (*E)
3042       return;
3043   }
3044   if (!Stack.back().IsExportNode) {
3045     *E = malformedError("node is not an export node in export trie data at "
3046                         "node: 0x" +
3047                         Twine::utohexstr(Stack.back().Start - Trie.begin()));
3048     moveToEnd();
3049     return;
3050   }
3051 }
3052 
3053 // We have a trie data structure and need a way to walk it that is compatible
3054 // with the C++ iterator model. The solution is a non-recursive depth first
3055 // traversal where the iterator contains a stack of parent nodes along with a
3056 // string that is the accumulation of all edge strings along the parent chain
3057 // to this point.
3058 //
3059 // There is one "export" node for each exported symbol.  But because some
3060 // symbols may be a prefix of another symbol (e.g. _dup and _dup2), an export
3061 // node may have child nodes too.
3062 //
3063 // The algorithm for moveNext() is to keep moving down the leftmost unvisited
3064 // child until hitting a node with no children (which is an export node or
3065 // else the trie is malformed). On the way down, each node is pushed on the
3066 // stack ivar.  If there is no more ways down, it pops up one and tries to go
3067 // down a sibling path until a childless node is reached.
3068 void ExportEntry::moveNext() {
3069   assert(!Stack.empty() && "ExportEntry::moveNext() with empty node stack");
3070   if (!Stack.back().IsExportNode) {
3071     *E = malformedError("node is not an export node in export trie data at "
3072                         "node: 0x" +
3073                         Twine::utohexstr(Stack.back().Start - Trie.begin()));
3074     moveToEnd();
3075     return;
3076   }
3077 
3078   Stack.pop_back();
3079   while (!Stack.empty()) {
3080     NodeState &Top = Stack.back();
3081     if (Top.NextChildIndex < Top.ChildCount) {
3082       pushDownUntilBottom();
3083       // Now at the next export node.
3084       return;
3085     } else {
3086       if (Top.IsExportNode) {
3087         // This node has no children but is itself an export node.
3088         CumulativeString.resize(Top.ParentStringLength);
3089         return;
3090       }
3091       Stack.pop_back();
3092     }
3093   }
3094   Done = true;
3095 }
3096 
3097 iterator_range<export_iterator>
3098 MachOObjectFile::exports(Error &E, ArrayRef<uint8_t> Trie,
3099                          const MachOObjectFile *O) {
3100   ExportEntry Start(&E, O, Trie);
3101   if (Trie.empty())
3102     Start.moveToEnd();
3103   else
3104     Start.moveToFirst();
3105 
3106   ExportEntry Finish(&E, O, Trie);
3107   Finish.moveToEnd();
3108 
3109   return make_range(export_iterator(Start), export_iterator(Finish));
3110 }
3111 
3112 iterator_range<export_iterator> MachOObjectFile::exports(Error &Err) const {
3113   return exports(Err, getDyldInfoExportsTrie(), this);
3114 }
3115 
3116 MachORebaseEntry::MachORebaseEntry(Error *E, const MachOObjectFile *O,
3117                                    ArrayRef<uint8_t> Bytes, bool is64Bit)
3118     : E(E), O(O), Opcodes(Bytes), Ptr(Bytes.begin()),
3119       PointerSize(is64Bit ? 8 : 4) {}
3120 
3121 void MachORebaseEntry::moveToFirst() {
3122   Ptr = Opcodes.begin();
3123   moveNext();
3124 }
3125 
3126 void MachORebaseEntry::moveToEnd() {
3127   Ptr = Opcodes.end();
3128   RemainingLoopCount = 0;
3129   Done = true;
3130 }
3131 
3132 void MachORebaseEntry::moveNext() {
3133   ErrorAsOutParameter ErrAsOutParam(E);
3134   // If in the middle of some loop, move to next rebasing in loop.
3135   SegmentOffset += AdvanceAmount;
3136   if (RemainingLoopCount) {
3137     --RemainingLoopCount;
3138     return;
3139   }
3140   // REBASE_OPCODE_DONE is only used for padding if we are not aligned to
3141   // pointer size. Therefore it is possible to reach the end without ever having
3142   // seen REBASE_OPCODE_DONE.
3143   if (Ptr == Opcodes.end()) {
3144     Done = true;
3145     return;
3146   }
3147   bool More = true;
3148   while (More) {
3149     // Parse next opcode and set up next loop.
3150     const uint8_t *OpcodeStart = Ptr;
3151     uint8_t Byte = *Ptr++;
3152     uint8_t ImmValue = Byte & MachO::REBASE_IMMEDIATE_MASK;
3153     uint8_t Opcode = Byte & MachO::REBASE_OPCODE_MASK;
3154     uint32_t Count, Skip;
3155     const char *error = nullptr;
3156     switch (Opcode) {
3157     case MachO::REBASE_OPCODE_DONE:
3158       More = false;
3159       Done = true;
3160       moveToEnd();
3161       DEBUG_WITH_TYPE("mach-o-rebase", dbgs() << "REBASE_OPCODE_DONE\n");
3162       break;
3163     case MachO::REBASE_OPCODE_SET_TYPE_IMM:
3164       RebaseType = ImmValue;
3165       if (RebaseType > MachO::REBASE_TYPE_TEXT_PCREL32) {
3166         *E = malformedError("for REBASE_OPCODE_SET_TYPE_IMM bad bind type: " +
3167                             Twine((int)RebaseType) + " for opcode at: 0x" +
3168                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3169         moveToEnd();
3170         return;
3171       }
3172       DEBUG_WITH_TYPE(
3173           "mach-o-rebase",
3174           dbgs() << "REBASE_OPCODE_SET_TYPE_IMM: "
3175                  << "RebaseType=" << (int) RebaseType << "\n");
3176       break;
3177     case MachO::REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
3178       SegmentIndex = ImmValue;
3179       SegmentOffset = readULEB128(&error);
3180       if (error) {
3181         *E = malformedError("for REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB " +
3182                             Twine(error) + " for opcode at: 0x" +
3183                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3184         moveToEnd();
3185         return;
3186       }
3187       error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3188                                                PointerSize);
3189       if (error) {
3190         *E = malformedError("for REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB " +
3191                             Twine(error) + " for opcode at: 0x" +
3192                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3193         moveToEnd();
3194         return;
3195       }
3196       DEBUG_WITH_TYPE(
3197           "mach-o-rebase",
3198           dbgs() << "REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB: "
3199                  << "SegmentIndex=" << SegmentIndex << ", "
3200                  << format("SegmentOffset=0x%06X", SegmentOffset)
3201                  << "\n");
3202       break;
3203     case MachO::REBASE_OPCODE_ADD_ADDR_ULEB:
3204       SegmentOffset += readULEB128(&error);
3205       if (error) {
3206         *E = malformedError("for REBASE_OPCODE_ADD_ADDR_ULEB " + Twine(error) +
3207                             " for opcode at: 0x" +
3208                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3209         moveToEnd();
3210         return;
3211       }
3212       error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3213                                                PointerSize);
3214       if (error) {
3215         *E = malformedError("for REBASE_OPCODE_ADD_ADDR_ULEB " + Twine(error) +
3216                             " for opcode at: 0x" +
3217                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3218         moveToEnd();
3219         return;
3220       }
3221       DEBUG_WITH_TYPE("mach-o-rebase",
3222                       dbgs() << "REBASE_OPCODE_ADD_ADDR_ULEB: "
3223                              << format("SegmentOffset=0x%06X",
3224                                        SegmentOffset) << "\n");
3225       break;
3226     case MachO::REBASE_OPCODE_ADD_ADDR_IMM_SCALED:
3227       SegmentOffset += ImmValue * PointerSize;
3228       error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3229                                                PointerSize);
3230       if (error) {
3231         *E = malformedError("for REBASE_OPCODE_ADD_ADDR_IMM_SCALED " +
3232                             Twine(error) + " for opcode at: 0x" +
3233                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3234         moveToEnd();
3235         return;
3236       }
3237       DEBUG_WITH_TYPE("mach-o-rebase",
3238                       dbgs() << "REBASE_OPCODE_ADD_ADDR_IMM_SCALED: "
3239                              << format("SegmentOffset=0x%06X",
3240                                        SegmentOffset) << "\n");
3241       break;
3242     case MachO::REBASE_OPCODE_DO_REBASE_IMM_TIMES:
3243       AdvanceAmount = PointerSize;
3244       Skip = 0;
3245       Count = ImmValue;
3246       if (ImmValue != 0)
3247         RemainingLoopCount = ImmValue - 1;
3248       else
3249         RemainingLoopCount = 0;
3250       error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3251                                                PointerSize, Count, Skip);
3252       if (error) {
3253         *E = malformedError("for REBASE_OPCODE_DO_REBASE_IMM_TIMES " +
3254                             Twine(error) + " for opcode at: 0x" +
3255                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3256         moveToEnd();
3257         return;
3258       }
3259       DEBUG_WITH_TYPE(
3260           "mach-o-rebase",
3261           dbgs() << "REBASE_OPCODE_DO_REBASE_IMM_TIMES: "
3262                  << format("SegmentOffset=0x%06X", SegmentOffset)
3263                  << ", AdvanceAmount=" << AdvanceAmount
3264                  << ", RemainingLoopCount=" << RemainingLoopCount
3265                  << "\n");
3266       return;
3267     case MachO::REBASE_OPCODE_DO_REBASE_ULEB_TIMES:
3268       AdvanceAmount = PointerSize;
3269       Skip = 0;
3270       Count = readULEB128(&error);
3271       if (error) {
3272         *E = malformedError("for REBASE_OPCODE_DO_REBASE_ULEB_TIMES " +
3273                             Twine(error) + " for opcode at: 0x" +
3274                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3275         moveToEnd();
3276         return;
3277       }
3278       if (Count != 0)
3279         RemainingLoopCount = Count - 1;
3280       else
3281         RemainingLoopCount = 0;
3282       error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3283                                                PointerSize, Count, Skip);
3284       if (error) {
3285         *E = malformedError("for REBASE_OPCODE_DO_REBASE_ULEB_TIMES " +
3286                             Twine(error) + " for opcode at: 0x" +
3287                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3288         moveToEnd();
3289         return;
3290       }
3291       DEBUG_WITH_TYPE(
3292           "mach-o-rebase",
3293           dbgs() << "REBASE_OPCODE_DO_REBASE_ULEB_TIMES: "
3294                  << format("SegmentOffset=0x%06X", SegmentOffset)
3295                  << ", AdvanceAmount=" << AdvanceAmount
3296                  << ", RemainingLoopCount=" << RemainingLoopCount
3297                  << "\n");
3298       return;
3299     case MachO::REBASE_OPCODE_DO_REBASE_ADD_ADDR_ULEB:
3300       Skip = readULEB128(&error);
3301       if (error) {
3302         *E = malformedError("for REBASE_OPCODE_DO_REBASE_ADD_ADDR_ULEB " +
3303                             Twine(error) + " for opcode at: 0x" +
3304                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3305         moveToEnd();
3306         return;
3307       }
3308       AdvanceAmount = Skip + PointerSize;
3309       Count = 1;
3310       RemainingLoopCount = 0;
3311       error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3312                                                PointerSize, Count, Skip);
3313       if (error) {
3314         *E = malformedError("for REBASE_OPCODE_DO_REBASE_ADD_ADDR_ULEB " +
3315                             Twine(error) + " for opcode at: 0x" +
3316                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3317         moveToEnd();
3318         return;
3319       }
3320       DEBUG_WITH_TYPE(
3321           "mach-o-rebase",
3322           dbgs() << "REBASE_OPCODE_DO_REBASE_ADD_ADDR_ULEB: "
3323                  << format("SegmentOffset=0x%06X", SegmentOffset)
3324                  << ", AdvanceAmount=" << AdvanceAmount
3325                  << ", RemainingLoopCount=" << RemainingLoopCount
3326                  << "\n");
3327       return;
3328     case MachO::REBASE_OPCODE_DO_REBASE_ULEB_TIMES_SKIPPING_ULEB:
3329       Count = readULEB128(&error);
3330       if (error) {
3331         *E = malformedError("for REBASE_OPCODE_DO_REBASE_ULEB_TIMES_SKIPPING_"
3332                             "ULEB " +
3333                             Twine(error) + " for opcode at: 0x" +
3334                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3335         moveToEnd();
3336         return;
3337       }
3338       if (Count != 0)
3339         RemainingLoopCount = Count - 1;
3340       else
3341         RemainingLoopCount = 0;
3342       Skip = readULEB128(&error);
3343       if (error) {
3344         *E = malformedError("for REBASE_OPCODE_DO_REBASE_ULEB_TIMES_SKIPPING_"
3345                             "ULEB " +
3346                             Twine(error) + " for opcode at: 0x" +
3347                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3348         moveToEnd();
3349         return;
3350       }
3351       AdvanceAmount = Skip + PointerSize;
3352 
3353       error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3354                                                PointerSize, Count, Skip);
3355       if (error) {
3356         *E = malformedError("for REBASE_OPCODE_DO_REBASE_ULEB_TIMES_SKIPPING_"
3357                             "ULEB " +
3358                             Twine(error) + " for opcode at: 0x" +
3359                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3360         moveToEnd();
3361         return;
3362       }
3363       DEBUG_WITH_TYPE(
3364           "mach-o-rebase",
3365           dbgs() << "REBASE_OPCODE_DO_REBASE_ULEB_TIMES_SKIPPING_ULEB: "
3366                  << format("SegmentOffset=0x%06X", SegmentOffset)
3367                  << ", AdvanceAmount=" << AdvanceAmount
3368                  << ", RemainingLoopCount=" << RemainingLoopCount
3369                  << "\n");
3370       return;
3371     default:
3372       *E = malformedError("bad rebase info (bad opcode value 0x" +
3373                           Twine::utohexstr(Opcode) + " for opcode at: 0x" +
3374                           Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3375       moveToEnd();
3376       return;
3377     }
3378   }
3379 }
3380 
3381 uint64_t MachORebaseEntry::readULEB128(const char **error) {
3382   unsigned Count;
3383   uint64_t Result = decodeULEB128(Ptr, &Count, Opcodes.end(), error);
3384   Ptr += Count;
3385   if (Ptr > Opcodes.end())
3386     Ptr = Opcodes.end();
3387   return Result;
3388 }
3389 
3390 int32_t MachORebaseEntry::segmentIndex() const { return SegmentIndex; }
3391 
3392 uint64_t MachORebaseEntry::segmentOffset() const { return SegmentOffset; }
3393 
3394 StringRef MachORebaseEntry::typeName() const {
3395   switch (RebaseType) {
3396   case MachO::REBASE_TYPE_POINTER:
3397     return "pointer";
3398   case MachO::REBASE_TYPE_TEXT_ABSOLUTE32:
3399     return "text abs32";
3400   case MachO::REBASE_TYPE_TEXT_PCREL32:
3401     return "text rel32";
3402   }
3403   return "unknown";
3404 }
3405 
3406 // For use with the SegIndex of a checked Mach-O Rebase entry
3407 // to get the segment name.
3408 StringRef MachORebaseEntry::segmentName() const {
3409   return O->BindRebaseSegmentName(SegmentIndex);
3410 }
3411 
3412 // For use with a SegIndex,SegOffset pair from a checked Mach-O Rebase entry
3413 // to get the section name.
3414 StringRef MachORebaseEntry::sectionName() const {
3415   return O->BindRebaseSectionName(SegmentIndex, SegmentOffset);
3416 }
3417 
3418 // For use with a SegIndex,SegOffset pair from a checked Mach-O Rebase entry
3419 // to get the address.
3420 uint64_t MachORebaseEntry::address() const {
3421   return O->BindRebaseAddress(SegmentIndex, SegmentOffset);
3422 }
3423 
3424 bool MachORebaseEntry::operator==(const MachORebaseEntry &Other) const {
3425 #ifdef EXPENSIVE_CHECKS
3426   assert(Opcodes == Other.Opcodes && "compare iterators of different files");
3427 #else
3428   assert(Opcodes.data() == Other.Opcodes.data() && "compare iterators of different files");
3429 #endif
3430   return (Ptr == Other.Ptr) &&
3431          (RemainingLoopCount == Other.RemainingLoopCount) &&
3432          (Done == Other.Done);
3433 }
3434 
3435 iterator_range<rebase_iterator>
3436 MachOObjectFile::rebaseTable(Error &Err, MachOObjectFile *O,
3437                              ArrayRef<uint8_t> Opcodes, bool is64) {
3438   if (O->BindRebaseSectionTable == nullptr)
3439     O->BindRebaseSectionTable = std::make_unique<BindRebaseSegInfo>(O);
3440   MachORebaseEntry Start(&Err, O, Opcodes, is64);
3441   Start.moveToFirst();
3442 
3443   MachORebaseEntry Finish(&Err, O, Opcodes, is64);
3444   Finish.moveToEnd();
3445 
3446   return make_range(rebase_iterator(Start), rebase_iterator(Finish));
3447 }
3448 
3449 iterator_range<rebase_iterator> MachOObjectFile::rebaseTable(Error &Err) {
3450   return rebaseTable(Err, this, getDyldInfoRebaseOpcodes(), is64Bit());
3451 }
3452 
3453 MachOBindEntry::MachOBindEntry(Error *E, const MachOObjectFile *O,
3454                                ArrayRef<uint8_t> Bytes, bool is64Bit, Kind BK)
3455     : E(E), O(O), Opcodes(Bytes), Ptr(Bytes.begin()),
3456       PointerSize(is64Bit ? 8 : 4), TableKind(BK) {}
3457 
3458 void MachOBindEntry::moveToFirst() {
3459   Ptr = Opcodes.begin();
3460   moveNext();
3461 }
3462 
3463 void MachOBindEntry::moveToEnd() {
3464   Ptr = Opcodes.end();
3465   RemainingLoopCount = 0;
3466   Done = true;
3467 }
3468 
3469 void MachOBindEntry::moveNext() {
3470   ErrorAsOutParameter ErrAsOutParam(E);
3471   // If in the middle of some loop, move to next binding in loop.
3472   SegmentOffset += AdvanceAmount;
3473   if (RemainingLoopCount) {
3474     --RemainingLoopCount;
3475     return;
3476   }
3477   // BIND_OPCODE_DONE is only used for padding if we are not aligned to
3478   // pointer size. Therefore it is possible to reach the end without ever having
3479   // seen BIND_OPCODE_DONE.
3480   if (Ptr == Opcodes.end()) {
3481     Done = true;
3482     return;
3483   }
3484   bool More = true;
3485   while (More) {
3486     // Parse next opcode and set up next loop.
3487     const uint8_t *OpcodeStart = Ptr;
3488     uint8_t Byte = *Ptr++;
3489     uint8_t ImmValue = Byte & MachO::BIND_IMMEDIATE_MASK;
3490     uint8_t Opcode = Byte & MachO::BIND_OPCODE_MASK;
3491     int8_t SignExtended;
3492     const uint8_t *SymStart;
3493     uint32_t Count, Skip;
3494     const char *error = nullptr;
3495     switch (Opcode) {
3496     case MachO::BIND_OPCODE_DONE:
3497       if (TableKind == Kind::Lazy) {
3498         // Lazying bindings have a DONE opcode between entries.  Need to ignore
3499         // it to advance to next entry.  But need not if this is last entry.
3500         bool NotLastEntry = false;
3501         for (const uint8_t *P = Ptr; P < Opcodes.end(); ++P) {
3502           if (*P) {
3503             NotLastEntry = true;
3504           }
3505         }
3506         if (NotLastEntry)
3507           break;
3508       }
3509       More = false;
3510       moveToEnd();
3511       DEBUG_WITH_TYPE("mach-o-bind", dbgs() << "BIND_OPCODE_DONE\n");
3512       break;
3513     case MachO::BIND_OPCODE_SET_DYLIB_ORDINAL_IMM:
3514       if (TableKind == Kind::Weak) {
3515         *E = malformedError("BIND_OPCODE_SET_DYLIB_ORDINAL_IMM not allowed in "
3516                             "weak bind table for opcode at: 0x" +
3517                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3518         moveToEnd();
3519         return;
3520       }
3521       Ordinal = ImmValue;
3522       LibraryOrdinalSet = true;
3523       if (ImmValue > O->getLibraryCount()) {
3524         *E = malformedError("for BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB bad "
3525                             "library ordinal: " +
3526                             Twine((int)ImmValue) + " (max " +
3527                             Twine((int)O->getLibraryCount()) +
3528                             ") for opcode at: 0x" +
3529                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3530         moveToEnd();
3531         return;
3532       }
3533       DEBUG_WITH_TYPE(
3534           "mach-o-bind",
3535           dbgs() << "BIND_OPCODE_SET_DYLIB_ORDINAL_IMM: "
3536                  << "Ordinal=" << Ordinal << "\n");
3537       break;
3538     case MachO::BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB:
3539       if (TableKind == Kind::Weak) {
3540         *E = malformedError("BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB not allowed in "
3541                             "weak bind table for opcode at: 0x" +
3542                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3543         moveToEnd();
3544         return;
3545       }
3546       Ordinal = readULEB128(&error);
3547       LibraryOrdinalSet = true;
3548       if (error) {
3549         *E = malformedError("for BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB " +
3550                             Twine(error) + " for opcode at: 0x" +
3551                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3552         moveToEnd();
3553         return;
3554       }
3555       if (Ordinal > (int)O->getLibraryCount()) {
3556         *E = malformedError("for BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB bad "
3557                             "library ordinal: " +
3558                             Twine((int)Ordinal) + " (max " +
3559                             Twine((int)O->getLibraryCount()) +
3560                             ") for opcode at: 0x" +
3561                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3562         moveToEnd();
3563         return;
3564       }
3565       DEBUG_WITH_TYPE(
3566           "mach-o-bind",
3567           dbgs() << "BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB: "
3568                  << "Ordinal=" << Ordinal << "\n");
3569       break;
3570     case MachO::BIND_OPCODE_SET_DYLIB_SPECIAL_IMM:
3571       if (TableKind == Kind::Weak) {
3572         *E = malformedError("BIND_OPCODE_SET_DYLIB_SPECIAL_IMM not allowed in "
3573                             "weak bind table for opcode at: 0x" +
3574                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3575         moveToEnd();
3576         return;
3577       }
3578       if (ImmValue) {
3579         SignExtended = MachO::BIND_OPCODE_MASK | ImmValue;
3580         Ordinal = SignExtended;
3581         if (Ordinal < MachO::BIND_SPECIAL_DYLIB_FLAT_LOOKUP) {
3582           *E = malformedError("for BIND_OPCODE_SET_DYLIB_SPECIAL_IMM unknown "
3583                               "special ordinal: " +
3584                               Twine((int)Ordinal) + " for opcode at: 0x" +
3585                               Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3586           moveToEnd();
3587           return;
3588         }
3589       } else
3590         Ordinal = 0;
3591       LibraryOrdinalSet = true;
3592       DEBUG_WITH_TYPE(
3593           "mach-o-bind",
3594           dbgs() << "BIND_OPCODE_SET_DYLIB_SPECIAL_IMM: "
3595                  << "Ordinal=" << Ordinal << "\n");
3596       break;
3597     case MachO::BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM:
3598       Flags = ImmValue;
3599       SymStart = Ptr;
3600       while (*Ptr && (Ptr < Opcodes.end())) {
3601         ++Ptr;
3602       }
3603       if (Ptr == Opcodes.end()) {
3604         *E = malformedError(
3605             "for BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM "
3606             "symbol name extends past opcodes for opcode at: 0x" +
3607             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3608         moveToEnd();
3609         return;
3610       }
3611       SymbolName = StringRef(reinterpret_cast<const char*>(SymStart),
3612                              Ptr-SymStart);
3613       ++Ptr;
3614       DEBUG_WITH_TYPE(
3615           "mach-o-bind",
3616           dbgs() << "BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM: "
3617                  << "SymbolName=" << SymbolName << "\n");
3618       if (TableKind == Kind::Weak) {
3619         if (ImmValue & MachO::BIND_SYMBOL_FLAGS_NON_WEAK_DEFINITION)
3620           return;
3621       }
3622       break;
3623     case MachO::BIND_OPCODE_SET_TYPE_IMM:
3624       BindType = ImmValue;
3625       if (ImmValue > MachO::BIND_TYPE_TEXT_PCREL32) {
3626         *E = malformedError("for BIND_OPCODE_SET_TYPE_IMM bad bind type: " +
3627                             Twine((int)ImmValue) + " for opcode at: 0x" +
3628                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3629         moveToEnd();
3630         return;
3631       }
3632       DEBUG_WITH_TYPE(
3633           "mach-o-bind",
3634           dbgs() << "BIND_OPCODE_SET_TYPE_IMM: "
3635                  << "BindType=" << (int)BindType << "\n");
3636       break;
3637     case MachO::BIND_OPCODE_SET_ADDEND_SLEB:
3638       Addend = readSLEB128(&error);
3639       if (error) {
3640         *E = malformedError("for BIND_OPCODE_SET_ADDEND_SLEB " + Twine(error) +
3641                             " for opcode at: 0x" +
3642                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3643         moveToEnd();
3644         return;
3645       }
3646       DEBUG_WITH_TYPE(
3647           "mach-o-bind",
3648           dbgs() << "BIND_OPCODE_SET_ADDEND_SLEB: "
3649                  << "Addend=" << Addend << "\n");
3650       break;
3651     case MachO::BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
3652       SegmentIndex = ImmValue;
3653       SegmentOffset = readULEB128(&error);
3654       if (error) {
3655         *E = malformedError("for BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB " +
3656                             Twine(error) + " for opcode at: 0x" +
3657                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3658         moveToEnd();
3659         return;
3660       }
3661       error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3662                                              PointerSize);
3663       if (error) {
3664         *E = malformedError("for BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB " +
3665                             Twine(error) + " for opcode at: 0x" +
3666                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3667         moveToEnd();
3668         return;
3669       }
3670       DEBUG_WITH_TYPE(
3671           "mach-o-bind",
3672           dbgs() << "BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB: "
3673                  << "SegmentIndex=" << SegmentIndex << ", "
3674                  << format("SegmentOffset=0x%06X", SegmentOffset)
3675                  << "\n");
3676       break;
3677     case MachO::BIND_OPCODE_ADD_ADDR_ULEB:
3678       SegmentOffset += readULEB128(&error);
3679       if (error) {
3680         *E = malformedError("for BIND_OPCODE_ADD_ADDR_ULEB " + Twine(error) +
3681                             " for opcode at: 0x" +
3682                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3683         moveToEnd();
3684         return;
3685       }
3686       error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3687                                              PointerSize);
3688       if (error) {
3689         *E = malformedError("for BIND_OPCODE_ADD_ADDR_ULEB " + Twine(error) +
3690                             " for opcode at: 0x" +
3691                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3692         moveToEnd();
3693         return;
3694       }
3695       DEBUG_WITH_TYPE("mach-o-bind",
3696                       dbgs() << "BIND_OPCODE_ADD_ADDR_ULEB: "
3697                              << format("SegmentOffset=0x%06X",
3698                                        SegmentOffset) << "\n");
3699       break;
3700     case MachO::BIND_OPCODE_DO_BIND:
3701       AdvanceAmount = PointerSize;
3702       RemainingLoopCount = 0;
3703       error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3704                                              PointerSize);
3705       if (error) {
3706         *E = malformedError("for BIND_OPCODE_DO_BIND " + Twine(error) +
3707                             " for opcode at: 0x" +
3708                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3709         moveToEnd();
3710         return;
3711       }
3712       if (SymbolName == StringRef()) {
3713         *E = malformedError(
3714             "for BIND_OPCODE_DO_BIND missing preceding "
3715             "BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM for opcode at: 0x" +
3716             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3717         moveToEnd();
3718         return;
3719       }
3720       if (!LibraryOrdinalSet && TableKind != Kind::Weak) {
3721         *E =
3722             malformedError("for BIND_OPCODE_DO_BIND missing preceding "
3723                            "BIND_OPCODE_SET_DYLIB_ORDINAL_* for opcode at: 0x" +
3724                            Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3725         moveToEnd();
3726         return;
3727       }
3728       DEBUG_WITH_TYPE("mach-o-bind",
3729                       dbgs() << "BIND_OPCODE_DO_BIND: "
3730                              << format("SegmentOffset=0x%06X",
3731                                        SegmentOffset) << "\n");
3732       return;
3733      case MachO::BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB:
3734       if (TableKind == Kind::Lazy) {
3735         *E = malformedError("BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB not allowed in "
3736                             "lazy bind table for opcode at: 0x" +
3737                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3738         moveToEnd();
3739         return;
3740       }
3741       error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3742                                              PointerSize);
3743       if (error) {
3744         *E = malformedError("for BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB " +
3745                             Twine(error) + " for opcode at: 0x" +
3746                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3747         moveToEnd();
3748         return;
3749       }
3750       if (SymbolName == StringRef()) {
3751         *E = malformedError(
3752             "for BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB missing "
3753             "preceding BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM for opcode "
3754             "at: 0x" +
3755             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3756         moveToEnd();
3757         return;
3758       }
3759       if (!LibraryOrdinalSet && TableKind != Kind::Weak) {
3760         *E = malformedError(
3761             "for BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB missing "
3762             "preceding BIND_OPCODE_SET_DYLIB_ORDINAL_* for opcode at: 0x" +
3763             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3764         moveToEnd();
3765         return;
3766       }
3767       AdvanceAmount = readULEB128(&error) + PointerSize;
3768       if (error) {
3769         *E = malformedError("for BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB " +
3770                             Twine(error) + " for opcode at: 0x" +
3771                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3772         moveToEnd();
3773         return;
3774       }
3775       // Note, this is not really an error until the next bind but make no sense
3776       // for a BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB to not be followed by another
3777       // bind operation.
3778       error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset +
3779                                             AdvanceAmount, PointerSize);
3780       if (error) {
3781         *E = malformedError("for BIND_OPCODE_ADD_ADDR_ULEB (after adding "
3782                             "ULEB) " +
3783                             Twine(error) + " for opcode at: 0x" +
3784                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3785         moveToEnd();
3786         return;
3787       }
3788       RemainingLoopCount = 0;
3789       DEBUG_WITH_TYPE(
3790           "mach-o-bind",
3791           dbgs() << "BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB: "
3792                  << format("SegmentOffset=0x%06X", SegmentOffset)
3793                  << ", AdvanceAmount=" << AdvanceAmount
3794                  << ", RemainingLoopCount=" << RemainingLoopCount
3795                  << "\n");
3796       return;
3797     case MachO::BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED:
3798       if (TableKind == Kind::Lazy) {
3799         *E = malformedError("BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED not "
3800                             "allowed in lazy bind table for opcode at: 0x" +
3801                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3802         moveToEnd();
3803         return;
3804       }
3805       if (SymbolName == StringRef()) {
3806         *E = malformedError(
3807             "for BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED "
3808             "missing preceding BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM for "
3809             "opcode at: 0x" +
3810             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3811         moveToEnd();
3812         return;
3813       }
3814       if (!LibraryOrdinalSet && TableKind != Kind::Weak) {
3815         *E = malformedError(
3816             "for BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED "
3817             "missing preceding BIND_OPCODE_SET_DYLIB_ORDINAL_* for opcode "
3818             "at: 0x" +
3819             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3820         moveToEnd();
3821         return;
3822       }
3823       AdvanceAmount = ImmValue * PointerSize + PointerSize;
3824       RemainingLoopCount = 0;
3825       error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset +
3826                                              AdvanceAmount, PointerSize);
3827       if (error) {
3828         *E = malformedError("for BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED " +
3829                             Twine(error) + " for opcode at: 0x" +
3830                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3831         moveToEnd();
3832         return;
3833       }
3834       DEBUG_WITH_TYPE("mach-o-bind",
3835                       dbgs()
3836                       << "BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED: "
3837                       << format("SegmentOffset=0x%06X", SegmentOffset) << "\n");
3838       return;
3839     case MachO::BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB:
3840       if (TableKind == Kind::Lazy) {
3841         *E = malformedError("BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB not "
3842                             "allowed in lazy bind table for opcode at: 0x" +
3843                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3844         moveToEnd();
3845         return;
3846       }
3847       Count = readULEB128(&error);
3848       if (Count != 0)
3849         RemainingLoopCount = Count - 1;
3850       else
3851         RemainingLoopCount = 0;
3852       if (error) {
3853         *E = malformedError("for BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB "
3854                             " (count value) " +
3855                             Twine(error) + " for opcode at: 0x" +
3856                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3857         moveToEnd();
3858         return;
3859       }
3860       Skip = readULEB128(&error);
3861       AdvanceAmount = Skip + PointerSize;
3862       if (error) {
3863         *E = malformedError("for BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB "
3864                             " (skip value) " +
3865                             Twine(error) + " for opcode at: 0x" +
3866                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3867         moveToEnd();
3868         return;
3869       }
3870       if (SymbolName == StringRef()) {
3871         *E = malformedError(
3872             "for BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB "
3873             "missing preceding BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM for "
3874             "opcode at: 0x" +
3875             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3876         moveToEnd();
3877         return;
3878       }
3879       if (!LibraryOrdinalSet && TableKind != Kind::Weak) {
3880         *E = malformedError(
3881             "for BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB "
3882             "missing preceding BIND_OPCODE_SET_DYLIB_ORDINAL_* for opcode "
3883             "at: 0x" +
3884             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3885         moveToEnd();
3886         return;
3887       }
3888       error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3889                                              PointerSize, Count, Skip);
3890       if (error) {
3891         *E =
3892             malformedError("for BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB " +
3893                            Twine(error) + " for opcode at: 0x" +
3894                            Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3895         moveToEnd();
3896         return;
3897       }
3898       DEBUG_WITH_TYPE(
3899           "mach-o-bind",
3900           dbgs() << "BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB: "
3901                  << format("SegmentOffset=0x%06X", SegmentOffset)
3902                  << ", AdvanceAmount=" << AdvanceAmount
3903                  << ", RemainingLoopCount=" << RemainingLoopCount
3904                  << "\n");
3905       return;
3906     default:
3907       *E = malformedError("bad bind info (bad opcode value 0x" +
3908                           Twine::utohexstr(Opcode) + " for opcode at: 0x" +
3909                           Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3910       moveToEnd();
3911       return;
3912     }
3913   }
3914 }
3915 
3916 uint64_t MachOBindEntry::readULEB128(const char **error) {
3917   unsigned Count;
3918   uint64_t Result = decodeULEB128(Ptr, &Count, Opcodes.end(), error);
3919   Ptr += Count;
3920   if (Ptr > Opcodes.end())
3921     Ptr = Opcodes.end();
3922   return Result;
3923 }
3924 
3925 int64_t MachOBindEntry::readSLEB128(const char **error) {
3926   unsigned Count;
3927   int64_t Result = decodeSLEB128(Ptr, &Count, Opcodes.end(), error);
3928   Ptr += Count;
3929   if (Ptr > Opcodes.end())
3930     Ptr = Opcodes.end();
3931   return Result;
3932 }
3933 
3934 int32_t MachOBindEntry::segmentIndex() const { return SegmentIndex; }
3935 
3936 uint64_t MachOBindEntry::segmentOffset() const { return SegmentOffset; }
3937 
3938 StringRef MachOBindEntry::typeName() const {
3939   switch (BindType) {
3940   case MachO::BIND_TYPE_POINTER:
3941     return "pointer";
3942   case MachO::BIND_TYPE_TEXT_ABSOLUTE32:
3943     return "text abs32";
3944   case MachO::BIND_TYPE_TEXT_PCREL32:
3945     return "text rel32";
3946   }
3947   return "unknown";
3948 }
3949 
3950 StringRef MachOBindEntry::symbolName() const { return SymbolName; }
3951 
3952 int64_t MachOBindEntry::addend() const { return Addend; }
3953 
3954 uint32_t MachOBindEntry::flags() const { return Flags; }
3955 
3956 int MachOBindEntry::ordinal() const { return Ordinal; }
3957 
3958 // For use with the SegIndex of a checked Mach-O Bind entry
3959 // to get the segment name.
3960 StringRef MachOBindEntry::segmentName() const {
3961   return O->BindRebaseSegmentName(SegmentIndex);
3962 }
3963 
3964 // For use with a SegIndex,SegOffset pair from a checked Mach-O Bind entry
3965 // to get the section name.
3966 StringRef MachOBindEntry::sectionName() const {
3967   return O->BindRebaseSectionName(SegmentIndex, SegmentOffset);
3968 }
3969 
3970 // For use with a SegIndex,SegOffset pair from a checked Mach-O Bind entry
3971 // to get the address.
3972 uint64_t MachOBindEntry::address() const {
3973   return O->BindRebaseAddress(SegmentIndex, SegmentOffset);
3974 }
3975 
3976 bool MachOBindEntry::operator==(const MachOBindEntry &Other) const {
3977 #ifdef EXPENSIVE_CHECKS
3978   assert(Opcodes == Other.Opcodes && "compare iterators of different files");
3979 #else
3980   assert(Opcodes.data() == Other.Opcodes.data() && "compare iterators of different files");
3981 #endif
3982   return (Ptr == Other.Ptr) &&
3983          (RemainingLoopCount == Other.RemainingLoopCount) &&
3984          (Done == Other.Done);
3985 }
3986 
3987 // Build table of sections so SegIndex/SegOffset pairs can be translated.
3988 BindRebaseSegInfo::BindRebaseSegInfo(const object::MachOObjectFile *Obj) {
3989   uint32_t CurSegIndex = Obj->hasPageZeroSegment() ? 1 : 0;
3990   StringRef CurSegName;
3991   uint64_t CurSegAddress;
3992   for (const SectionRef &Section : Obj->sections()) {
3993     SectionInfo Info;
3994     Expected<StringRef> NameOrErr = Section.getName();
3995     if (!NameOrErr)
3996       consumeError(NameOrErr.takeError());
3997     else
3998       Info.SectionName = *NameOrErr;
3999     Info.Address = Section.getAddress();
4000     Info.Size = Section.getSize();
4001     Info.SegmentName =
4002         Obj->getSectionFinalSegmentName(Section.getRawDataRefImpl());
4003     if (!Info.SegmentName.equals(CurSegName)) {
4004       ++CurSegIndex;
4005       CurSegName = Info.SegmentName;
4006       CurSegAddress = Info.Address;
4007     }
4008     Info.SegmentIndex = CurSegIndex - 1;
4009     Info.OffsetInSegment = Info.Address - CurSegAddress;
4010     Info.SegmentStartAddress = CurSegAddress;
4011     Sections.push_back(Info);
4012   }
4013   MaxSegIndex = CurSegIndex;
4014 }
4015 
4016 // For use with a SegIndex, SegOffset, and PointerSize triple in
4017 // MachOBindEntry::moveNext() to validate a MachOBindEntry or MachORebaseEntry.
4018 //
4019 // Given a SegIndex, SegOffset, and PointerSize, verify a valid section exists
4020 // that fully contains a pointer at that location. Multiple fixups in a bind
4021 // (such as with the BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB opcode) can
4022 // be tested via the Count and Skip parameters.
4023 const char * BindRebaseSegInfo::checkSegAndOffsets(int32_t SegIndex,
4024                                                    uint64_t SegOffset,
4025                                                    uint8_t PointerSize,
4026                                                    uint32_t Count,
4027                                                    uint32_t Skip) {
4028   if (SegIndex == -1)
4029     return "missing preceding *_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB";
4030   if (SegIndex >= MaxSegIndex)
4031     return "bad segIndex (too large)";
4032   for (uint32_t i = 0; i < Count; ++i) {
4033     uint32_t Start = SegOffset + i * (PointerSize + Skip);
4034     uint32_t End = Start + PointerSize;
4035     bool Found = false;
4036     for (const SectionInfo &SI : Sections) {
4037       if (SI.SegmentIndex != SegIndex)
4038         continue;
4039       if ((SI.OffsetInSegment<=Start) && (Start<(SI.OffsetInSegment+SI.Size))) {
4040         if (End <= SI.OffsetInSegment + SI.Size) {
4041           Found = true;
4042           break;
4043         }
4044         else
4045           return "bad offset, extends beyond section boundary";
4046       }
4047     }
4048     if (!Found)
4049       return "bad offset, not in section";
4050   }
4051   return nullptr;
4052 }
4053 
4054 // For use with the SegIndex of a checked Mach-O Bind or Rebase entry
4055 // to get the segment name.
4056 StringRef BindRebaseSegInfo::segmentName(int32_t SegIndex) {
4057   for (const SectionInfo &SI : Sections) {
4058     if (SI.SegmentIndex == SegIndex)
4059       return SI.SegmentName;
4060   }
4061   llvm_unreachable("invalid SegIndex");
4062 }
4063 
4064 // For use with a SegIndex,SegOffset pair from a checked Mach-O Bind or Rebase
4065 // to get the SectionInfo.
4066 const BindRebaseSegInfo::SectionInfo &BindRebaseSegInfo::findSection(
4067                                      int32_t SegIndex, uint64_t SegOffset) {
4068   for (const SectionInfo &SI : Sections) {
4069     if (SI.SegmentIndex != SegIndex)
4070       continue;
4071     if (SI.OffsetInSegment > SegOffset)
4072       continue;
4073     if (SegOffset >= (SI.OffsetInSegment + SI.Size))
4074       continue;
4075     return SI;
4076   }
4077   llvm_unreachable("SegIndex and SegOffset not in any section");
4078 }
4079 
4080 // For use with a SegIndex,SegOffset pair from a checked Mach-O Bind or Rebase
4081 // entry to get the section name.
4082 StringRef BindRebaseSegInfo::sectionName(int32_t SegIndex,
4083                                          uint64_t SegOffset) {
4084   return findSection(SegIndex, SegOffset).SectionName;
4085 }
4086 
4087 // For use with a SegIndex,SegOffset pair from a checked Mach-O Bind or Rebase
4088 // entry to get the address.
4089 uint64_t BindRebaseSegInfo::address(uint32_t SegIndex, uint64_t OffsetInSeg) {
4090   const SectionInfo &SI = findSection(SegIndex, OffsetInSeg);
4091   return SI.SegmentStartAddress + OffsetInSeg;
4092 }
4093 
4094 iterator_range<bind_iterator>
4095 MachOObjectFile::bindTable(Error &Err, MachOObjectFile *O,
4096                            ArrayRef<uint8_t> Opcodes, bool is64,
4097                            MachOBindEntry::Kind BKind) {
4098   if (O->BindRebaseSectionTable == nullptr)
4099     O->BindRebaseSectionTable = std::make_unique<BindRebaseSegInfo>(O);
4100   MachOBindEntry Start(&Err, O, Opcodes, is64, BKind);
4101   Start.moveToFirst();
4102 
4103   MachOBindEntry Finish(&Err, O, Opcodes, is64, BKind);
4104   Finish.moveToEnd();
4105 
4106   return make_range(bind_iterator(Start), bind_iterator(Finish));
4107 }
4108 
4109 iterator_range<bind_iterator> MachOObjectFile::bindTable(Error &Err) {
4110   return bindTable(Err, this, getDyldInfoBindOpcodes(), is64Bit(),
4111                    MachOBindEntry::Kind::Regular);
4112 }
4113 
4114 iterator_range<bind_iterator> MachOObjectFile::lazyBindTable(Error &Err) {
4115   return bindTable(Err, this, getDyldInfoLazyBindOpcodes(), is64Bit(),
4116                    MachOBindEntry::Kind::Lazy);
4117 }
4118 
4119 iterator_range<bind_iterator> MachOObjectFile::weakBindTable(Error &Err) {
4120   return bindTable(Err, this, getDyldInfoWeakBindOpcodes(), is64Bit(),
4121                    MachOBindEntry::Kind::Weak);
4122 }
4123 
4124 MachOObjectFile::load_command_iterator
4125 MachOObjectFile::begin_load_commands() const {
4126   return LoadCommands.begin();
4127 }
4128 
4129 MachOObjectFile::load_command_iterator
4130 MachOObjectFile::end_load_commands() const {
4131   return LoadCommands.end();
4132 }
4133 
4134 iterator_range<MachOObjectFile::load_command_iterator>
4135 MachOObjectFile::load_commands() const {
4136   return make_range(begin_load_commands(), end_load_commands());
4137 }
4138 
4139 StringRef
4140 MachOObjectFile::getSectionFinalSegmentName(DataRefImpl Sec) const {
4141   ArrayRef<char> Raw = getSectionRawFinalSegmentName(Sec);
4142   return parseSegmentOrSectionName(Raw.data());
4143 }
4144 
4145 ArrayRef<char>
4146 MachOObjectFile::getSectionRawName(DataRefImpl Sec) const {
4147   assert(Sec.d.a < Sections.size() && "Should have detected this earlier");
4148   const section_base *Base =
4149     reinterpret_cast<const section_base *>(Sections[Sec.d.a]);
4150   return makeArrayRef(Base->sectname);
4151 }
4152 
4153 ArrayRef<char>
4154 MachOObjectFile::getSectionRawFinalSegmentName(DataRefImpl Sec) const {
4155   assert(Sec.d.a < Sections.size() && "Should have detected this earlier");
4156   const section_base *Base =
4157     reinterpret_cast<const section_base *>(Sections[Sec.d.a]);
4158   return makeArrayRef(Base->segname);
4159 }
4160 
4161 bool
4162 MachOObjectFile::isRelocationScattered(const MachO::any_relocation_info &RE)
4163   const {
4164   if (getCPUType(*this) == MachO::CPU_TYPE_X86_64)
4165     return false;
4166   return getPlainRelocationAddress(RE) & MachO::R_SCATTERED;
4167 }
4168 
4169 unsigned MachOObjectFile::getPlainRelocationSymbolNum(
4170     const MachO::any_relocation_info &RE) const {
4171   if (isLittleEndian())
4172     return RE.r_word1 & 0xffffff;
4173   return RE.r_word1 >> 8;
4174 }
4175 
4176 bool MachOObjectFile::getPlainRelocationExternal(
4177     const MachO::any_relocation_info &RE) const {
4178   if (isLittleEndian())
4179     return (RE.r_word1 >> 27) & 1;
4180   return (RE.r_word1 >> 4) & 1;
4181 }
4182 
4183 bool MachOObjectFile::getScatteredRelocationScattered(
4184     const MachO::any_relocation_info &RE) const {
4185   return RE.r_word0 >> 31;
4186 }
4187 
4188 uint32_t MachOObjectFile::getScatteredRelocationValue(
4189     const MachO::any_relocation_info &RE) const {
4190   return RE.r_word1;
4191 }
4192 
4193 uint32_t MachOObjectFile::getScatteredRelocationType(
4194     const MachO::any_relocation_info &RE) const {
4195   return (RE.r_word0 >> 24) & 0xf;
4196 }
4197 
4198 unsigned MachOObjectFile::getAnyRelocationAddress(
4199     const MachO::any_relocation_info &RE) const {
4200   if (isRelocationScattered(RE))
4201     return getScatteredRelocationAddress(RE);
4202   return getPlainRelocationAddress(RE);
4203 }
4204 
4205 unsigned MachOObjectFile::getAnyRelocationPCRel(
4206     const MachO::any_relocation_info &RE) const {
4207   if (isRelocationScattered(RE))
4208     return getScatteredRelocationPCRel(RE);
4209   return getPlainRelocationPCRel(*this, RE);
4210 }
4211 
4212 unsigned MachOObjectFile::getAnyRelocationLength(
4213     const MachO::any_relocation_info &RE) const {
4214   if (isRelocationScattered(RE))
4215     return getScatteredRelocationLength(RE);
4216   return getPlainRelocationLength(*this, RE);
4217 }
4218 
4219 unsigned
4220 MachOObjectFile::getAnyRelocationType(
4221                                    const MachO::any_relocation_info &RE) const {
4222   if (isRelocationScattered(RE))
4223     return getScatteredRelocationType(RE);
4224   return getPlainRelocationType(*this, RE);
4225 }
4226 
4227 SectionRef
4228 MachOObjectFile::getAnyRelocationSection(
4229                                    const MachO::any_relocation_info &RE) const {
4230   if (isRelocationScattered(RE) || getPlainRelocationExternal(RE))
4231     return *section_end();
4232   unsigned SecNum = getPlainRelocationSymbolNum(RE);
4233   if (SecNum == MachO::R_ABS || SecNum > Sections.size())
4234     return *section_end();
4235   DataRefImpl DRI;
4236   DRI.d.a = SecNum - 1;
4237   return SectionRef(DRI, this);
4238 }
4239 
4240 MachO::section MachOObjectFile::getSection(DataRefImpl DRI) const {
4241   assert(DRI.d.a < Sections.size() && "Should have detected this earlier");
4242   return getStruct<MachO::section>(*this, Sections[DRI.d.a]);
4243 }
4244 
4245 MachO::section_64 MachOObjectFile::getSection64(DataRefImpl DRI) const {
4246   assert(DRI.d.a < Sections.size() && "Should have detected this earlier");
4247   return getStruct<MachO::section_64>(*this, Sections[DRI.d.a]);
4248 }
4249 
4250 MachO::section MachOObjectFile::getSection(const LoadCommandInfo &L,
4251                                            unsigned Index) const {
4252   const char *Sec = getSectionPtr(*this, L, Index);
4253   return getStruct<MachO::section>(*this, Sec);
4254 }
4255 
4256 MachO::section_64 MachOObjectFile::getSection64(const LoadCommandInfo &L,
4257                                                 unsigned Index) const {
4258   const char *Sec = getSectionPtr(*this, L, Index);
4259   return getStruct<MachO::section_64>(*this, Sec);
4260 }
4261 
4262 MachO::nlist
4263 MachOObjectFile::getSymbolTableEntry(DataRefImpl DRI) const {
4264   const char *P = reinterpret_cast<const char *>(DRI.p);
4265   return getStruct<MachO::nlist>(*this, P);
4266 }
4267 
4268 MachO::nlist_64
4269 MachOObjectFile::getSymbol64TableEntry(DataRefImpl DRI) const {
4270   const char *P = reinterpret_cast<const char *>(DRI.p);
4271   return getStruct<MachO::nlist_64>(*this, P);
4272 }
4273 
4274 MachO::linkedit_data_command
4275 MachOObjectFile::getLinkeditDataLoadCommand(const LoadCommandInfo &L) const {
4276   return getStruct<MachO::linkedit_data_command>(*this, L.Ptr);
4277 }
4278 
4279 MachO::segment_command
4280 MachOObjectFile::getSegmentLoadCommand(const LoadCommandInfo &L) const {
4281   return getStruct<MachO::segment_command>(*this, L.Ptr);
4282 }
4283 
4284 MachO::segment_command_64
4285 MachOObjectFile::getSegment64LoadCommand(const LoadCommandInfo &L) const {
4286   return getStruct<MachO::segment_command_64>(*this, L.Ptr);
4287 }
4288 
4289 MachO::linker_option_command
4290 MachOObjectFile::getLinkerOptionLoadCommand(const LoadCommandInfo &L) const {
4291   return getStruct<MachO::linker_option_command>(*this, L.Ptr);
4292 }
4293 
4294 MachO::version_min_command
4295 MachOObjectFile::getVersionMinLoadCommand(const LoadCommandInfo &L) const {
4296   return getStruct<MachO::version_min_command>(*this, L.Ptr);
4297 }
4298 
4299 MachO::note_command
4300 MachOObjectFile::getNoteLoadCommand(const LoadCommandInfo &L) const {
4301   return getStruct<MachO::note_command>(*this, L.Ptr);
4302 }
4303 
4304 MachO::build_version_command
4305 MachOObjectFile::getBuildVersionLoadCommand(const LoadCommandInfo &L) const {
4306   return getStruct<MachO::build_version_command>(*this, L.Ptr);
4307 }
4308 
4309 MachO::build_tool_version
4310 MachOObjectFile::getBuildToolVersion(unsigned index) const {
4311   return getStruct<MachO::build_tool_version>(*this, BuildTools[index]);
4312 }
4313 
4314 MachO::dylib_command
4315 MachOObjectFile::getDylibIDLoadCommand(const LoadCommandInfo &L) const {
4316   return getStruct<MachO::dylib_command>(*this, L.Ptr);
4317 }
4318 
4319 MachO::dyld_info_command
4320 MachOObjectFile::getDyldInfoLoadCommand(const LoadCommandInfo &L) const {
4321   return getStruct<MachO::dyld_info_command>(*this, L.Ptr);
4322 }
4323 
4324 MachO::dylinker_command
4325 MachOObjectFile::getDylinkerCommand(const LoadCommandInfo &L) const {
4326   return getStruct<MachO::dylinker_command>(*this, L.Ptr);
4327 }
4328 
4329 MachO::uuid_command
4330 MachOObjectFile::getUuidCommand(const LoadCommandInfo &L) const {
4331   return getStruct<MachO::uuid_command>(*this, L.Ptr);
4332 }
4333 
4334 MachO::rpath_command
4335 MachOObjectFile::getRpathCommand(const LoadCommandInfo &L) const {
4336   return getStruct<MachO::rpath_command>(*this, L.Ptr);
4337 }
4338 
4339 MachO::source_version_command
4340 MachOObjectFile::getSourceVersionCommand(const LoadCommandInfo &L) const {
4341   return getStruct<MachO::source_version_command>(*this, L.Ptr);
4342 }
4343 
4344 MachO::entry_point_command
4345 MachOObjectFile::getEntryPointCommand(const LoadCommandInfo &L) const {
4346   return getStruct<MachO::entry_point_command>(*this, L.Ptr);
4347 }
4348 
4349 MachO::encryption_info_command
4350 MachOObjectFile::getEncryptionInfoCommand(const LoadCommandInfo &L) const {
4351   return getStruct<MachO::encryption_info_command>(*this, L.Ptr);
4352 }
4353 
4354 MachO::encryption_info_command_64
4355 MachOObjectFile::getEncryptionInfoCommand64(const LoadCommandInfo &L) const {
4356   return getStruct<MachO::encryption_info_command_64>(*this, L.Ptr);
4357 }
4358 
4359 MachO::sub_framework_command
4360 MachOObjectFile::getSubFrameworkCommand(const LoadCommandInfo &L) const {
4361   return getStruct<MachO::sub_framework_command>(*this, L.Ptr);
4362 }
4363 
4364 MachO::sub_umbrella_command
4365 MachOObjectFile::getSubUmbrellaCommand(const LoadCommandInfo &L) const {
4366   return getStruct<MachO::sub_umbrella_command>(*this, L.Ptr);
4367 }
4368 
4369 MachO::sub_library_command
4370 MachOObjectFile::getSubLibraryCommand(const LoadCommandInfo &L) const {
4371   return getStruct<MachO::sub_library_command>(*this, L.Ptr);
4372 }
4373 
4374 MachO::sub_client_command
4375 MachOObjectFile::getSubClientCommand(const LoadCommandInfo &L) const {
4376   return getStruct<MachO::sub_client_command>(*this, L.Ptr);
4377 }
4378 
4379 MachO::routines_command
4380 MachOObjectFile::getRoutinesCommand(const LoadCommandInfo &L) const {
4381   return getStruct<MachO::routines_command>(*this, L.Ptr);
4382 }
4383 
4384 MachO::routines_command_64
4385 MachOObjectFile::getRoutinesCommand64(const LoadCommandInfo &L) const {
4386   return getStruct<MachO::routines_command_64>(*this, L.Ptr);
4387 }
4388 
4389 MachO::thread_command
4390 MachOObjectFile::getThreadCommand(const LoadCommandInfo &L) const {
4391   return getStruct<MachO::thread_command>(*this, L.Ptr);
4392 }
4393 
4394 MachO::any_relocation_info
4395 MachOObjectFile::getRelocation(DataRefImpl Rel) const {
4396   uint32_t Offset;
4397   if (getHeader().filetype == MachO::MH_OBJECT) {
4398     DataRefImpl Sec;
4399     Sec.d.a = Rel.d.a;
4400     if (is64Bit()) {
4401       MachO::section_64 Sect = getSection64(Sec);
4402       Offset = Sect.reloff;
4403     } else {
4404       MachO::section Sect = getSection(Sec);
4405       Offset = Sect.reloff;
4406     }
4407   } else {
4408     MachO::dysymtab_command DysymtabLoadCmd = getDysymtabLoadCommand();
4409     if (Rel.d.a == 0)
4410       Offset = DysymtabLoadCmd.extreloff; // Offset to the external relocations
4411     else
4412       Offset = DysymtabLoadCmd.locreloff; // Offset to the local relocations
4413   }
4414 
4415   auto P = reinterpret_cast<const MachO::any_relocation_info *>(
4416       getPtr(*this, Offset)) + Rel.d.b;
4417   return getStruct<MachO::any_relocation_info>(
4418       *this, reinterpret_cast<const char *>(P));
4419 }
4420 
4421 MachO::data_in_code_entry
4422 MachOObjectFile::getDice(DataRefImpl Rel) const {
4423   const char *P = reinterpret_cast<const char *>(Rel.p);
4424   return getStruct<MachO::data_in_code_entry>(*this, P);
4425 }
4426 
4427 const MachO::mach_header &MachOObjectFile::getHeader() const {
4428   return Header;
4429 }
4430 
4431 const MachO::mach_header_64 &MachOObjectFile::getHeader64() const {
4432   assert(is64Bit());
4433   return Header64;
4434 }
4435 
4436 uint32_t MachOObjectFile::getIndirectSymbolTableEntry(
4437                                              const MachO::dysymtab_command &DLC,
4438                                              unsigned Index) const {
4439   uint64_t Offset = DLC.indirectsymoff + Index * sizeof(uint32_t);
4440   return getStruct<uint32_t>(*this, getPtr(*this, Offset));
4441 }
4442 
4443 MachO::data_in_code_entry
4444 MachOObjectFile::getDataInCodeTableEntry(uint32_t DataOffset,
4445                                          unsigned Index) const {
4446   uint64_t Offset = DataOffset + Index * sizeof(MachO::data_in_code_entry);
4447   return getStruct<MachO::data_in_code_entry>(*this, getPtr(*this, Offset));
4448 }
4449 
4450 MachO::symtab_command MachOObjectFile::getSymtabLoadCommand() const {
4451   if (SymtabLoadCmd)
4452     return getStruct<MachO::symtab_command>(*this, SymtabLoadCmd);
4453 
4454   // If there is no SymtabLoadCmd return a load command with zero'ed fields.
4455   MachO::symtab_command Cmd;
4456   Cmd.cmd = MachO::LC_SYMTAB;
4457   Cmd.cmdsize = sizeof(MachO::symtab_command);
4458   Cmd.symoff = 0;
4459   Cmd.nsyms = 0;
4460   Cmd.stroff = 0;
4461   Cmd.strsize = 0;
4462   return Cmd;
4463 }
4464 
4465 MachO::dysymtab_command MachOObjectFile::getDysymtabLoadCommand() const {
4466   if (DysymtabLoadCmd)
4467     return getStruct<MachO::dysymtab_command>(*this, DysymtabLoadCmd);
4468 
4469   // If there is no DysymtabLoadCmd return a load command with zero'ed fields.
4470   MachO::dysymtab_command Cmd;
4471   Cmd.cmd = MachO::LC_DYSYMTAB;
4472   Cmd.cmdsize = sizeof(MachO::dysymtab_command);
4473   Cmd.ilocalsym = 0;
4474   Cmd.nlocalsym = 0;
4475   Cmd.iextdefsym = 0;
4476   Cmd.nextdefsym = 0;
4477   Cmd.iundefsym = 0;
4478   Cmd.nundefsym = 0;
4479   Cmd.tocoff = 0;
4480   Cmd.ntoc = 0;
4481   Cmd.modtaboff = 0;
4482   Cmd.nmodtab = 0;
4483   Cmd.extrefsymoff = 0;
4484   Cmd.nextrefsyms = 0;
4485   Cmd.indirectsymoff = 0;
4486   Cmd.nindirectsyms = 0;
4487   Cmd.extreloff = 0;
4488   Cmd.nextrel = 0;
4489   Cmd.locreloff = 0;
4490   Cmd.nlocrel = 0;
4491   return Cmd;
4492 }
4493 
4494 MachO::linkedit_data_command
4495 MachOObjectFile::getDataInCodeLoadCommand() const {
4496   if (DataInCodeLoadCmd)
4497     return getStruct<MachO::linkedit_data_command>(*this, DataInCodeLoadCmd);
4498 
4499   // If there is no DataInCodeLoadCmd return a load command with zero'ed fields.
4500   MachO::linkedit_data_command Cmd;
4501   Cmd.cmd = MachO::LC_DATA_IN_CODE;
4502   Cmd.cmdsize = sizeof(MachO::linkedit_data_command);
4503   Cmd.dataoff = 0;
4504   Cmd.datasize = 0;
4505   return Cmd;
4506 }
4507 
4508 MachO::linkedit_data_command
4509 MachOObjectFile::getLinkOptHintsLoadCommand() const {
4510   if (LinkOptHintsLoadCmd)
4511     return getStruct<MachO::linkedit_data_command>(*this, LinkOptHintsLoadCmd);
4512 
4513   // If there is no LinkOptHintsLoadCmd return a load command with zero'ed
4514   // fields.
4515   MachO::linkedit_data_command Cmd;
4516   Cmd.cmd = MachO::LC_LINKER_OPTIMIZATION_HINT;
4517   Cmd.cmdsize = sizeof(MachO::linkedit_data_command);
4518   Cmd.dataoff = 0;
4519   Cmd.datasize = 0;
4520   return Cmd;
4521 }
4522 
4523 ArrayRef<uint8_t> MachOObjectFile::getDyldInfoRebaseOpcodes() const {
4524   if (!DyldInfoLoadCmd)
4525     return None;
4526 
4527   auto DyldInfoOrErr =
4528     getStructOrErr<MachO::dyld_info_command>(*this, DyldInfoLoadCmd);
4529   if (!DyldInfoOrErr)
4530     return None;
4531   MachO::dyld_info_command DyldInfo = DyldInfoOrErr.get();
4532   const uint8_t *Ptr =
4533       reinterpret_cast<const uint8_t *>(getPtr(*this, DyldInfo.rebase_off));
4534   return makeArrayRef(Ptr, DyldInfo.rebase_size);
4535 }
4536 
4537 ArrayRef<uint8_t> MachOObjectFile::getDyldInfoBindOpcodes() const {
4538   if (!DyldInfoLoadCmd)
4539     return None;
4540 
4541   auto DyldInfoOrErr =
4542     getStructOrErr<MachO::dyld_info_command>(*this, DyldInfoLoadCmd);
4543   if (!DyldInfoOrErr)
4544     return None;
4545   MachO::dyld_info_command DyldInfo = DyldInfoOrErr.get();
4546   const uint8_t *Ptr =
4547       reinterpret_cast<const uint8_t *>(getPtr(*this, DyldInfo.bind_off));
4548   return makeArrayRef(Ptr, DyldInfo.bind_size);
4549 }
4550 
4551 ArrayRef<uint8_t> MachOObjectFile::getDyldInfoWeakBindOpcodes() const {
4552   if (!DyldInfoLoadCmd)
4553     return None;
4554 
4555   auto DyldInfoOrErr =
4556     getStructOrErr<MachO::dyld_info_command>(*this, DyldInfoLoadCmd);
4557   if (!DyldInfoOrErr)
4558     return None;
4559   MachO::dyld_info_command DyldInfo = DyldInfoOrErr.get();
4560   const uint8_t *Ptr =
4561       reinterpret_cast<const uint8_t *>(getPtr(*this, DyldInfo.weak_bind_off));
4562   return makeArrayRef(Ptr, DyldInfo.weak_bind_size);
4563 }
4564 
4565 ArrayRef<uint8_t> MachOObjectFile::getDyldInfoLazyBindOpcodes() const {
4566   if (!DyldInfoLoadCmd)
4567     return None;
4568 
4569   auto DyldInfoOrErr =
4570     getStructOrErr<MachO::dyld_info_command>(*this, DyldInfoLoadCmd);
4571   if (!DyldInfoOrErr)
4572     return None;
4573   MachO::dyld_info_command DyldInfo = DyldInfoOrErr.get();
4574   const uint8_t *Ptr =
4575       reinterpret_cast<const uint8_t *>(getPtr(*this, DyldInfo.lazy_bind_off));
4576   return makeArrayRef(Ptr, DyldInfo.lazy_bind_size);
4577 }
4578 
4579 ArrayRef<uint8_t> MachOObjectFile::getDyldInfoExportsTrie() const {
4580   if (!DyldInfoLoadCmd)
4581     return None;
4582 
4583   auto DyldInfoOrErr =
4584     getStructOrErr<MachO::dyld_info_command>(*this, DyldInfoLoadCmd);
4585   if (!DyldInfoOrErr)
4586     return None;
4587   MachO::dyld_info_command DyldInfo = DyldInfoOrErr.get();
4588   const uint8_t *Ptr =
4589       reinterpret_cast<const uint8_t *>(getPtr(*this, DyldInfo.export_off));
4590   return makeArrayRef(Ptr, DyldInfo.export_size);
4591 }
4592 
4593 ArrayRef<uint8_t> MachOObjectFile::getUuid() const {
4594   if (!UuidLoadCmd)
4595     return None;
4596   // Returning a pointer is fine as uuid doesn't need endian swapping.
4597   const char *Ptr = UuidLoadCmd + offsetof(MachO::uuid_command, uuid);
4598   return makeArrayRef(reinterpret_cast<const uint8_t *>(Ptr), 16);
4599 }
4600 
4601 StringRef MachOObjectFile::getStringTableData() const {
4602   MachO::symtab_command S = getSymtabLoadCommand();
4603   return getData().substr(S.stroff, S.strsize);
4604 }
4605 
4606 bool MachOObjectFile::is64Bit() const {
4607   return getType() == getMachOType(false, true) ||
4608     getType() == getMachOType(true, true);
4609 }
4610 
4611 void MachOObjectFile::ReadULEB128s(uint64_t Index,
4612                                    SmallVectorImpl<uint64_t> &Out) const {
4613   DataExtractor extractor(ObjectFile::getData(), true, 0);
4614 
4615   uint64_t offset = Index;
4616   uint64_t data = 0;
4617   while (uint64_t delta = extractor.getULEB128(&offset)) {
4618     data += delta;
4619     Out.push_back(data);
4620   }
4621 }
4622 
4623 bool MachOObjectFile::isRelocatableObject() const {
4624   return getHeader().filetype == MachO::MH_OBJECT;
4625 }
4626 
4627 Expected<std::unique_ptr<MachOObjectFile>>
4628 ObjectFile::createMachOObjectFile(MemoryBufferRef Buffer,
4629                                   uint32_t UniversalCputype,
4630                                   uint32_t UniversalIndex) {
4631   StringRef Magic = Buffer.getBuffer().slice(0, 4);
4632   if (Magic == "\xFE\xED\xFA\xCE")
4633     return MachOObjectFile::create(Buffer, false, false,
4634                                    UniversalCputype, UniversalIndex);
4635   if (Magic == "\xCE\xFA\xED\xFE")
4636     return MachOObjectFile::create(Buffer, true, false,
4637                                    UniversalCputype, UniversalIndex);
4638   if (Magic == "\xFE\xED\xFA\xCF")
4639     return MachOObjectFile::create(Buffer, false, true,
4640                                    UniversalCputype, UniversalIndex);
4641   if (Magic == "\xCF\xFA\xED\xFE")
4642     return MachOObjectFile::create(Buffer, true, true,
4643                                    UniversalCputype, UniversalIndex);
4644   return make_error<GenericBinaryError>("Unrecognized MachO magic number",
4645                                         object_error::invalid_file_type);
4646 }
4647 
4648 StringRef MachOObjectFile::mapDebugSectionName(StringRef Name) const {
4649   return StringSwitch<StringRef>(Name)
4650       .Case("debug_str_offs", "debug_str_offsets")
4651       .Default(Name);
4652 }
4653