xref: /freebsd/contrib/llvm-project/llvm/lib/Object/MachOObjectFile.cpp (revision 62cfcf62f627e5093fb37026a6d8c98e4d2ef04c)
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 (isLoadCommandObsolete(Load.C.cmd)) {
1600       Err = malformedError("load command " + Twine(I) + " for cmd value of: " +
1601                            Twine(Load.C.cmd) + " is obsolete and not "
1602                            "supported");
1603       return;
1604     }
1605     // TODO: generate a error for unknown load commands by default.  But still
1606     // need work out an approach to allow or not allow unknown values like this
1607     // as an option for some uses like lldb.
1608     if (I < LoadCommandCount - 1) {
1609       if (auto LoadOrErr = getNextLoadCommandInfo(*this, I, Load))
1610         Load = *LoadOrErr;
1611       else {
1612         Err = LoadOrErr.takeError();
1613         return;
1614       }
1615     }
1616   }
1617   if (!SymtabLoadCmd) {
1618     if (DysymtabLoadCmd) {
1619       Err = malformedError("contains LC_DYSYMTAB load command without a "
1620                            "LC_SYMTAB load command");
1621       return;
1622     }
1623   } else if (DysymtabLoadCmd) {
1624     MachO::symtab_command Symtab =
1625       getStruct<MachO::symtab_command>(*this, SymtabLoadCmd);
1626     MachO::dysymtab_command Dysymtab =
1627       getStruct<MachO::dysymtab_command>(*this, DysymtabLoadCmd);
1628     if (Dysymtab.nlocalsym != 0 && Dysymtab.ilocalsym > Symtab.nsyms) {
1629       Err = malformedError("ilocalsym in LC_DYSYMTAB load command "
1630                            "extends past the end of the symbol table");
1631       return;
1632     }
1633     uint64_t BigSize = Dysymtab.ilocalsym;
1634     BigSize += Dysymtab.nlocalsym;
1635     if (Dysymtab.nlocalsym != 0 && BigSize > Symtab.nsyms) {
1636       Err = malformedError("ilocalsym plus nlocalsym in LC_DYSYMTAB load "
1637                            "command extends past the end of the symbol table");
1638       return;
1639     }
1640     if (Dysymtab.nextdefsym != 0 && Dysymtab.iextdefsym > Symtab.nsyms) {
1641       Err = malformedError("iextdefsym in LC_DYSYMTAB load command "
1642                            "extends past the end of the symbol table");
1643       return;
1644     }
1645     BigSize = Dysymtab.iextdefsym;
1646     BigSize += Dysymtab.nextdefsym;
1647     if (Dysymtab.nextdefsym != 0 && BigSize > Symtab.nsyms) {
1648       Err = malformedError("iextdefsym plus nextdefsym in LC_DYSYMTAB "
1649                            "load command extends past the end of the symbol "
1650                            "table");
1651       return;
1652     }
1653     if (Dysymtab.nundefsym != 0 && Dysymtab.iundefsym > Symtab.nsyms) {
1654       Err = malformedError("iundefsym in LC_DYSYMTAB load command "
1655                            "extends past the end of the symbol table");
1656       return;
1657     }
1658     BigSize = Dysymtab.iundefsym;
1659     BigSize += Dysymtab.nundefsym;
1660     if (Dysymtab.nundefsym != 0 && BigSize > Symtab.nsyms) {
1661       Err = malformedError("iundefsym plus nundefsym in LC_DYSYMTAB load "
1662                            " command extends past the end of the symbol table");
1663       return;
1664     }
1665   }
1666   if ((getHeader().filetype == MachO::MH_DYLIB ||
1667        getHeader().filetype == MachO::MH_DYLIB_STUB) &&
1668        DyldIdLoadCmd == nullptr) {
1669     Err = malformedError("no LC_ID_DYLIB load command in dynamic library "
1670                          "filetype");
1671     return;
1672   }
1673   assert(LoadCommands.size() == LoadCommandCount);
1674 
1675   Err = Error::success();
1676 }
1677 
1678 Error MachOObjectFile::checkSymbolTable() const {
1679   uint32_t Flags = 0;
1680   if (is64Bit()) {
1681     MachO::mach_header_64 H_64 = MachOObjectFile::getHeader64();
1682     Flags = H_64.flags;
1683   } else {
1684     MachO::mach_header H = MachOObjectFile::getHeader();
1685     Flags = H.flags;
1686   }
1687   uint8_t NType = 0;
1688   uint8_t NSect = 0;
1689   uint16_t NDesc = 0;
1690   uint32_t NStrx = 0;
1691   uint64_t NValue = 0;
1692   uint32_t SymbolIndex = 0;
1693   MachO::symtab_command S = getSymtabLoadCommand();
1694   for (const SymbolRef &Symbol : symbols()) {
1695     DataRefImpl SymDRI = Symbol.getRawDataRefImpl();
1696     if (is64Bit()) {
1697       MachO::nlist_64 STE_64 = getSymbol64TableEntry(SymDRI);
1698       NType = STE_64.n_type;
1699       NSect = STE_64.n_sect;
1700       NDesc = STE_64.n_desc;
1701       NStrx = STE_64.n_strx;
1702       NValue = STE_64.n_value;
1703     } else {
1704       MachO::nlist STE = getSymbolTableEntry(SymDRI);
1705       NType = STE.n_type;
1706       NSect = STE.n_sect;
1707       NDesc = STE.n_desc;
1708       NStrx = STE.n_strx;
1709       NValue = STE.n_value;
1710     }
1711     if ((NType & MachO::N_STAB) == 0) {
1712       if ((NType & MachO::N_TYPE) == MachO::N_SECT) {
1713         if (NSect == 0 || NSect > Sections.size())
1714           return malformedError("bad section index: " + Twine((int)NSect) +
1715                                 " for symbol at index " + Twine(SymbolIndex));
1716       }
1717       if ((NType & MachO::N_TYPE) == MachO::N_INDR) {
1718         if (NValue >= S.strsize)
1719           return malformedError("bad n_value: " + Twine((int)NValue) + " past "
1720                                 "the end of string table, for N_INDR symbol at "
1721                                 "index " + Twine(SymbolIndex));
1722       }
1723       if ((Flags & MachO::MH_TWOLEVEL) == MachO::MH_TWOLEVEL &&
1724           (((NType & MachO::N_TYPE) == MachO::N_UNDF && NValue == 0) ||
1725            (NType & MachO::N_TYPE) == MachO::N_PBUD)) {
1726             uint32_t LibraryOrdinal = MachO::GET_LIBRARY_ORDINAL(NDesc);
1727             if (LibraryOrdinal != 0 &&
1728                 LibraryOrdinal != MachO::EXECUTABLE_ORDINAL &&
1729                 LibraryOrdinal != MachO::DYNAMIC_LOOKUP_ORDINAL &&
1730                 LibraryOrdinal - 1 >= Libraries.size() ) {
1731               return malformedError("bad library ordinal: " + Twine(LibraryOrdinal) +
1732                                     " for symbol at index " + Twine(SymbolIndex));
1733             }
1734           }
1735     }
1736     if (NStrx >= S.strsize)
1737       return malformedError("bad string table index: " + Twine((int)NStrx) +
1738                             " past the end of string table, for symbol at "
1739                             "index " + Twine(SymbolIndex));
1740     SymbolIndex++;
1741   }
1742   return Error::success();
1743 }
1744 
1745 void MachOObjectFile::moveSymbolNext(DataRefImpl &Symb) const {
1746   unsigned SymbolTableEntrySize = is64Bit() ?
1747     sizeof(MachO::nlist_64) :
1748     sizeof(MachO::nlist);
1749   Symb.p += SymbolTableEntrySize;
1750 }
1751 
1752 Expected<StringRef> MachOObjectFile::getSymbolName(DataRefImpl Symb) const {
1753   StringRef StringTable = getStringTableData();
1754   MachO::nlist_base Entry = getSymbolTableEntryBase(*this, Symb);
1755   if (Entry.n_strx == 0)
1756     // A n_strx value of 0 indicates that no name is associated with a
1757     // particular symbol table entry.
1758     return StringRef();
1759   const char *Start = &StringTable.data()[Entry.n_strx];
1760   if (Start < getData().begin() || Start >= getData().end()) {
1761     return malformedError("bad string index: " + Twine(Entry.n_strx) +
1762                           " for symbol at index " + Twine(getSymbolIndex(Symb)));
1763   }
1764   return StringRef(Start);
1765 }
1766 
1767 unsigned MachOObjectFile::getSectionType(SectionRef Sec) const {
1768   DataRefImpl DRI = Sec.getRawDataRefImpl();
1769   uint32_t Flags = getSectionFlags(*this, DRI);
1770   return Flags & MachO::SECTION_TYPE;
1771 }
1772 
1773 uint64_t MachOObjectFile::getNValue(DataRefImpl Sym) const {
1774   if (is64Bit()) {
1775     MachO::nlist_64 Entry = getSymbol64TableEntry(Sym);
1776     return Entry.n_value;
1777   }
1778   MachO::nlist Entry = getSymbolTableEntry(Sym);
1779   return Entry.n_value;
1780 }
1781 
1782 // getIndirectName() returns the name of the alias'ed symbol who's string table
1783 // index is in the n_value field.
1784 std::error_code MachOObjectFile::getIndirectName(DataRefImpl Symb,
1785                                                  StringRef &Res) const {
1786   StringRef StringTable = getStringTableData();
1787   MachO::nlist_base Entry = getSymbolTableEntryBase(*this, Symb);
1788   if ((Entry.n_type & MachO::N_TYPE) != MachO::N_INDR)
1789     return object_error::parse_failed;
1790   uint64_t NValue = getNValue(Symb);
1791   if (NValue >= StringTable.size())
1792     return object_error::parse_failed;
1793   const char *Start = &StringTable.data()[NValue];
1794   Res = StringRef(Start);
1795   return std::error_code();
1796 }
1797 
1798 uint64_t MachOObjectFile::getSymbolValueImpl(DataRefImpl Sym) const {
1799   return getNValue(Sym);
1800 }
1801 
1802 Expected<uint64_t> MachOObjectFile::getSymbolAddress(DataRefImpl Sym) const {
1803   return getSymbolValue(Sym);
1804 }
1805 
1806 uint32_t MachOObjectFile::getSymbolAlignment(DataRefImpl DRI) const {
1807   uint32_t flags = getSymbolFlags(DRI);
1808   if (flags & SymbolRef::SF_Common) {
1809     MachO::nlist_base Entry = getSymbolTableEntryBase(*this, DRI);
1810     return 1 << MachO::GET_COMM_ALIGN(Entry.n_desc);
1811   }
1812   return 0;
1813 }
1814 
1815 uint64_t MachOObjectFile::getCommonSymbolSizeImpl(DataRefImpl DRI) const {
1816   return getNValue(DRI);
1817 }
1818 
1819 Expected<SymbolRef::Type>
1820 MachOObjectFile::getSymbolType(DataRefImpl Symb) const {
1821   MachO::nlist_base Entry = getSymbolTableEntryBase(*this, Symb);
1822   uint8_t n_type = Entry.n_type;
1823 
1824   // If this is a STAB debugging symbol, we can do nothing more.
1825   if (n_type & MachO::N_STAB)
1826     return SymbolRef::ST_Debug;
1827 
1828   switch (n_type & MachO::N_TYPE) {
1829     case MachO::N_UNDF :
1830       return SymbolRef::ST_Unknown;
1831     case MachO::N_SECT :
1832       Expected<section_iterator> SecOrError = getSymbolSection(Symb);
1833       if (!SecOrError)
1834         return SecOrError.takeError();
1835       section_iterator Sec = *SecOrError;
1836       if (Sec->isData() || Sec->isBSS())
1837         return SymbolRef::ST_Data;
1838       return SymbolRef::ST_Function;
1839   }
1840   return SymbolRef::ST_Other;
1841 }
1842 
1843 uint32_t MachOObjectFile::getSymbolFlags(DataRefImpl DRI) const {
1844   MachO::nlist_base Entry = getSymbolTableEntryBase(*this, DRI);
1845 
1846   uint8_t MachOType = Entry.n_type;
1847   uint16_t MachOFlags = Entry.n_desc;
1848 
1849   uint32_t Result = SymbolRef::SF_None;
1850 
1851   if ((MachOType & MachO::N_TYPE) == MachO::N_INDR)
1852     Result |= SymbolRef::SF_Indirect;
1853 
1854   if (MachOType & MachO::N_STAB)
1855     Result |= SymbolRef::SF_FormatSpecific;
1856 
1857   if (MachOType & MachO::N_EXT) {
1858     Result |= SymbolRef::SF_Global;
1859     if ((MachOType & MachO::N_TYPE) == MachO::N_UNDF) {
1860       if (getNValue(DRI))
1861         Result |= SymbolRef::SF_Common;
1862       else
1863         Result |= SymbolRef::SF_Undefined;
1864     }
1865 
1866     if (!(MachOType & MachO::N_PEXT))
1867       Result |= SymbolRef::SF_Exported;
1868   }
1869 
1870   if (MachOFlags & (MachO::N_WEAK_REF | MachO::N_WEAK_DEF))
1871     Result |= SymbolRef::SF_Weak;
1872 
1873   if (MachOFlags & (MachO::N_ARM_THUMB_DEF))
1874     Result |= SymbolRef::SF_Thumb;
1875 
1876   if ((MachOType & MachO::N_TYPE) == MachO::N_ABS)
1877     Result |= SymbolRef::SF_Absolute;
1878 
1879   return Result;
1880 }
1881 
1882 Expected<section_iterator>
1883 MachOObjectFile::getSymbolSection(DataRefImpl Symb) const {
1884   MachO::nlist_base Entry = getSymbolTableEntryBase(*this, Symb);
1885   uint8_t index = Entry.n_sect;
1886 
1887   if (index == 0)
1888     return section_end();
1889   DataRefImpl DRI;
1890   DRI.d.a = index - 1;
1891   if (DRI.d.a >= Sections.size()){
1892     return malformedError("bad section index: " + Twine((int)index) +
1893                           " for symbol at index " + Twine(getSymbolIndex(Symb)));
1894   }
1895   return section_iterator(SectionRef(DRI, this));
1896 }
1897 
1898 unsigned MachOObjectFile::getSymbolSectionID(SymbolRef Sym) const {
1899   MachO::nlist_base Entry =
1900       getSymbolTableEntryBase(*this, Sym.getRawDataRefImpl());
1901   return Entry.n_sect - 1;
1902 }
1903 
1904 void MachOObjectFile::moveSectionNext(DataRefImpl &Sec) const {
1905   Sec.d.a++;
1906 }
1907 
1908 Expected<StringRef> MachOObjectFile::getSectionName(DataRefImpl Sec) const {
1909   ArrayRef<char> Raw = getSectionRawName(Sec);
1910   return parseSegmentOrSectionName(Raw.data());
1911 }
1912 
1913 uint64_t MachOObjectFile::getSectionAddress(DataRefImpl Sec) const {
1914   if (is64Bit())
1915     return getSection64(Sec).addr;
1916   return getSection(Sec).addr;
1917 }
1918 
1919 uint64_t MachOObjectFile::getSectionIndex(DataRefImpl Sec) const {
1920   return Sec.d.a;
1921 }
1922 
1923 uint64_t MachOObjectFile::getSectionSize(DataRefImpl Sec) const {
1924   // In the case if a malformed Mach-O file where the section offset is past
1925   // the end of the file or some part of the section size is past the end of
1926   // the file return a size of zero or a size that covers the rest of the file
1927   // but does not extend past the end of the file.
1928   uint32_t SectOffset, SectType;
1929   uint64_t SectSize;
1930 
1931   if (is64Bit()) {
1932     MachO::section_64 Sect = getSection64(Sec);
1933     SectOffset = Sect.offset;
1934     SectSize = Sect.size;
1935     SectType = Sect.flags & MachO::SECTION_TYPE;
1936   } else {
1937     MachO::section Sect = getSection(Sec);
1938     SectOffset = Sect.offset;
1939     SectSize = Sect.size;
1940     SectType = Sect.flags & MachO::SECTION_TYPE;
1941   }
1942   if (SectType == MachO::S_ZEROFILL || SectType == MachO::S_GB_ZEROFILL)
1943     return SectSize;
1944   uint64_t FileSize = getData().size();
1945   if (SectOffset > FileSize)
1946     return 0;
1947   if (FileSize - SectOffset < SectSize)
1948     return FileSize - SectOffset;
1949   return SectSize;
1950 }
1951 
1952 ArrayRef<uint8_t> MachOObjectFile::getSectionContents(uint32_t Offset,
1953                                                       uint64_t Size) const {
1954   return arrayRefFromStringRef(getData().substr(Offset, Size));
1955 }
1956 
1957 Expected<ArrayRef<uint8_t>>
1958 MachOObjectFile::getSectionContents(DataRefImpl Sec) const {
1959   uint32_t Offset;
1960   uint64_t Size;
1961 
1962   if (is64Bit()) {
1963     MachO::section_64 Sect = getSection64(Sec);
1964     Offset = Sect.offset;
1965     Size = Sect.size;
1966   } else {
1967     MachO::section Sect = getSection(Sec);
1968     Offset = Sect.offset;
1969     Size = Sect.size;
1970   }
1971 
1972   return getSectionContents(Offset, Size);
1973 }
1974 
1975 uint64_t MachOObjectFile::getSectionAlignment(DataRefImpl Sec) const {
1976   uint32_t Align;
1977   if (is64Bit()) {
1978     MachO::section_64 Sect = getSection64(Sec);
1979     Align = Sect.align;
1980   } else {
1981     MachO::section Sect = getSection(Sec);
1982     Align = Sect.align;
1983   }
1984 
1985   return uint64_t(1) << Align;
1986 }
1987 
1988 Expected<SectionRef> MachOObjectFile::getSection(unsigned SectionIndex) const {
1989   if (SectionIndex < 1 || SectionIndex > Sections.size())
1990     return malformedError("bad section index: " + Twine((int)SectionIndex));
1991 
1992   DataRefImpl DRI;
1993   DRI.d.a = SectionIndex - 1;
1994   return SectionRef(DRI, this);
1995 }
1996 
1997 Expected<SectionRef> MachOObjectFile::getSection(StringRef SectionName) const {
1998   for (const SectionRef &Section : sections()) {
1999     auto NameOrErr = Section.getName();
2000     if (!NameOrErr)
2001       return NameOrErr.takeError();
2002     if (*NameOrErr == SectionName)
2003       return Section;
2004   }
2005   return errorCodeToError(object_error::parse_failed);
2006 }
2007 
2008 bool MachOObjectFile::isSectionCompressed(DataRefImpl Sec) const {
2009   return false;
2010 }
2011 
2012 bool MachOObjectFile::isSectionText(DataRefImpl Sec) const {
2013   uint32_t Flags = getSectionFlags(*this, Sec);
2014   return Flags & MachO::S_ATTR_PURE_INSTRUCTIONS;
2015 }
2016 
2017 bool MachOObjectFile::isSectionData(DataRefImpl Sec) const {
2018   uint32_t Flags = getSectionFlags(*this, Sec);
2019   unsigned SectionType = Flags & MachO::SECTION_TYPE;
2020   return !(Flags & MachO::S_ATTR_PURE_INSTRUCTIONS) &&
2021          !(SectionType == MachO::S_ZEROFILL ||
2022            SectionType == MachO::S_GB_ZEROFILL);
2023 }
2024 
2025 bool MachOObjectFile::isSectionBSS(DataRefImpl Sec) const {
2026   uint32_t Flags = getSectionFlags(*this, Sec);
2027   unsigned SectionType = Flags & MachO::SECTION_TYPE;
2028   return !(Flags & MachO::S_ATTR_PURE_INSTRUCTIONS) &&
2029          (SectionType == MachO::S_ZEROFILL ||
2030           SectionType == MachO::S_GB_ZEROFILL);
2031 }
2032 
2033 unsigned MachOObjectFile::getSectionID(SectionRef Sec) const {
2034   return Sec.getRawDataRefImpl().d.a;
2035 }
2036 
2037 bool MachOObjectFile::isSectionVirtual(DataRefImpl Sec) const {
2038   uint32_t Flags = getSectionFlags(*this, Sec);
2039   unsigned SectionType = Flags & MachO::SECTION_TYPE;
2040   return SectionType == MachO::S_ZEROFILL ||
2041          SectionType == MachO::S_GB_ZEROFILL;
2042 }
2043 
2044 bool MachOObjectFile::isSectionBitcode(DataRefImpl Sec) const {
2045   StringRef SegmentName = getSectionFinalSegmentName(Sec);
2046   if (Expected<StringRef> NameOrErr = getSectionName(Sec))
2047     return (SegmentName == "__LLVM" && *NameOrErr == "__bitcode");
2048   return false;
2049 }
2050 
2051 bool MachOObjectFile::isSectionStripped(DataRefImpl Sec) const {
2052   if (is64Bit())
2053     return getSection64(Sec).offset == 0;
2054   return getSection(Sec).offset == 0;
2055 }
2056 
2057 relocation_iterator MachOObjectFile::section_rel_begin(DataRefImpl Sec) const {
2058   DataRefImpl Ret;
2059   Ret.d.a = Sec.d.a;
2060   Ret.d.b = 0;
2061   return relocation_iterator(RelocationRef(Ret, this));
2062 }
2063 
2064 relocation_iterator
2065 MachOObjectFile::section_rel_end(DataRefImpl Sec) const {
2066   uint32_t Num;
2067   if (is64Bit()) {
2068     MachO::section_64 Sect = getSection64(Sec);
2069     Num = Sect.nreloc;
2070   } else {
2071     MachO::section Sect = getSection(Sec);
2072     Num = Sect.nreloc;
2073   }
2074 
2075   DataRefImpl Ret;
2076   Ret.d.a = Sec.d.a;
2077   Ret.d.b = Num;
2078   return relocation_iterator(RelocationRef(Ret, this));
2079 }
2080 
2081 relocation_iterator MachOObjectFile::extrel_begin() const {
2082   DataRefImpl Ret;
2083   // for DYSYMTAB symbols, Ret.d.a == 0 for external relocations
2084   Ret.d.a = 0; // Would normally be a section index.
2085   Ret.d.b = 0; // Index into the external relocations
2086   return relocation_iterator(RelocationRef(Ret, this));
2087 }
2088 
2089 relocation_iterator MachOObjectFile::extrel_end() const {
2090   MachO::dysymtab_command DysymtabLoadCmd = getDysymtabLoadCommand();
2091   DataRefImpl Ret;
2092   // for DYSYMTAB symbols, Ret.d.a == 0 for external relocations
2093   Ret.d.a = 0; // Would normally be a section index.
2094   Ret.d.b = DysymtabLoadCmd.nextrel; // Index into the external relocations
2095   return relocation_iterator(RelocationRef(Ret, this));
2096 }
2097 
2098 relocation_iterator MachOObjectFile::locrel_begin() const {
2099   DataRefImpl Ret;
2100   // for DYSYMTAB symbols, Ret.d.a == 1 for local relocations
2101   Ret.d.a = 1; // Would normally be a section index.
2102   Ret.d.b = 0; // Index into the local relocations
2103   return relocation_iterator(RelocationRef(Ret, this));
2104 }
2105 
2106 relocation_iterator MachOObjectFile::locrel_end() const {
2107   MachO::dysymtab_command DysymtabLoadCmd = getDysymtabLoadCommand();
2108   DataRefImpl Ret;
2109   // for DYSYMTAB symbols, Ret.d.a == 1 for local relocations
2110   Ret.d.a = 1; // Would normally be a section index.
2111   Ret.d.b = DysymtabLoadCmd.nlocrel; // Index into the local relocations
2112   return relocation_iterator(RelocationRef(Ret, this));
2113 }
2114 
2115 void MachOObjectFile::moveRelocationNext(DataRefImpl &Rel) const {
2116   ++Rel.d.b;
2117 }
2118 
2119 uint64_t MachOObjectFile::getRelocationOffset(DataRefImpl Rel) const {
2120   assert((getHeader().filetype == MachO::MH_OBJECT ||
2121           getHeader().filetype == MachO::MH_KEXT_BUNDLE) &&
2122          "Only implemented for MH_OBJECT && MH_KEXT_BUNDLE");
2123   MachO::any_relocation_info RE = getRelocation(Rel);
2124   return getAnyRelocationAddress(RE);
2125 }
2126 
2127 symbol_iterator
2128 MachOObjectFile::getRelocationSymbol(DataRefImpl Rel) const {
2129   MachO::any_relocation_info RE = getRelocation(Rel);
2130   if (isRelocationScattered(RE))
2131     return symbol_end();
2132 
2133   uint32_t SymbolIdx = getPlainRelocationSymbolNum(RE);
2134   bool isExtern = getPlainRelocationExternal(RE);
2135   if (!isExtern)
2136     return symbol_end();
2137 
2138   MachO::symtab_command S = getSymtabLoadCommand();
2139   unsigned SymbolTableEntrySize = is64Bit() ?
2140     sizeof(MachO::nlist_64) :
2141     sizeof(MachO::nlist);
2142   uint64_t Offset = S.symoff + SymbolIdx * SymbolTableEntrySize;
2143   DataRefImpl Sym;
2144   Sym.p = reinterpret_cast<uintptr_t>(getPtr(*this, Offset));
2145   return symbol_iterator(SymbolRef(Sym, this));
2146 }
2147 
2148 section_iterator
2149 MachOObjectFile::getRelocationSection(DataRefImpl Rel) const {
2150   return section_iterator(getAnyRelocationSection(getRelocation(Rel)));
2151 }
2152 
2153 uint64_t MachOObjectFile::getRelocationType(DataRefImpl Rel) const {
2154   MachO::any_relocation_info RE = getRelocation(Rel);
2155   return getAnyRelocationType(RE);
2156 }
2157 
2158 void MachOObjectFile::getRelocationTypeName(
2159     DataRefImpl Rel, SmallVectorImpl<char> &Result) const {
2160   StringRef res;
2161   uint64_t RType = getRelocationType(Rel);
2162 
2163   unsigned Arch = this->getArch();
2164 
2165   switch (Arch) {
2166     case Triple::x86: {
2167       static const char *const Table[] =  {
2168         "GENERIC_RELOC_VANILLA",
2169         "GENERIC_RELOC_PAIR",
2170         "GENERIC_RELOC_SECTDIFF",
2171         "GENERIC_RELOC_PB_LA_PTR",
2172         "GENERIC_RELOC_LOCAL_SECTDIFF",
2173         "GENERIC_RELOC_TLV" };
2174 
2175       if (RType > 5)
2176         res = "Unknown";
2177       else
2178         res = Table[RType];
2179       break;
2180     }
2181     case Triple::x86_64: {
2182       static const char *const Table[] =  {
2183         "X86_64_RELOC_UNSIGNED",
2184         "X86_64_RELOC_SIGNED",
2185         "X86_64_RELOC_BRANCH",
2186         "X86_64_RELOC_GOT_LOAD",
2187         "X86_64_RELOC_GOT",
2188         "X86_64_RELOC_SUBTRACTOR",
2189         "X86_64_RELOC_SIGNED_1",
2190         "X86_64_RELOC_SIGNED_2",
2191         "X86_64_RELOC_SIGNED_4",
2192         "X86_64_RELOC_TLV" };
2193 
2194       if (RType > 9)
2195         res = "Unknown";
2196       else
2197         res = Table[RType];
2198       break;
2199     }
2200     case Triple::arm: {
2201       static const char *const Table[] =  {
2202         "ARM_RELOC_VANILLA",
2203         "ARM_RELOC_PAIR",
2204         "ARM_RELOC_SECTDIFF",
2205         "ARM_RELOC_LOCAL_SECTDIFF",
2206         "ARM_RELOC_PB_LA_PTR",
2207         "ARM_RELOC_BR24",
2208         "ARM_THUMB_RELOC_BR22",
2209         "ARM_THUMB_32BIT_BRANCH",
2210         "ARM_RELOC_HALF",
2211         "ARM_RELOC_HALF_SECTDIFF" };
2212 
2213       if (RType > 9)
2214         res = "Unknown";
2215       else
2216         res = Table[RType];
2217       break;
2218     }
2219     case Triple::aarch64:
2220     case Triple::aarch64_32: {
2221       static const char *const Table[] = {
2222         "ARM64_RELOC_UNSIGNED",           "ARM64_RELOC_SUBTRACTOR",
2223         "ARM64_RELOC_BRANCH26",           "ARM64_RELOC_PAGE21",
2224         "ARM64_RELOC_PAGEOFF12",          "ARM64_RELOC_GOT_LOAD_PAGE21",
2225         "ARM64_RELOC_GOT_LOAD_PAGEOFF12", "ARM64_RELOC_POINTER_TO_GOT",
2226         "ARM64_RELOC_TLVP_LOAD_PAGE21",   "ARM64_RELOC_TLVP_LOAD_PAGEOFF12",
2227         "ARM64_RELOC_ADDEND"
2228       };
2229 
2230       if (RType >= array_lengthof(Table))
2231         res = "Unknown";
2232       else
2233         res = Table[RType];
2234       break;
2235     }
2236     case Triple::ppc: {
2237       static const char *const Table[] =  {
2238         "PPC_RELOC_VANILLA",
2239         "PPC_RELOC_PAIR",
2240         "PPC_RELOC_BR14",
2241         "PPC_RELOC_BR24",
2242         "PPC_RELOC_HI16",
2243         "PPC_RELOC_LO16",
2244         "PPC_RELOC_HA16",
2245         "PPC_RELOC_LO14",
2246         "PPC_RELOC_SECTDIFF",
2247         "PPC_RELOC_PB_LA_PTR",
2248         "PPC_RELOC_HI16_SECTDIFF",
2249         "PPC_RELOC_LO16_SECTDIFF",
2250         "PPC_RELOC_HA16_SECTDIFF",
2251         "PPC_RELOC_JBSR",
2252         "PPC_RELOC_LO14_SECTDIFF",
2253         "PPC_RELOC_LOCAL_SECTDIFF" };
2254 
2255       if (RType > 15)
2256         res = "Unknown";
2257       else
2258         res = Table[RType];
2259       break;
2260     }
2261     case Triple::UnknownArch:
2262       res = "Unknown";
2263       break;
2264   }
2265   Result.append(res.begin(), res.end());
2266 }
2267 
2268 uint8_t MachOObjectFile::getRelocationLength(DataRefImpl Rel) const {
2269   MachO::any_relocation_info RE = getRelocation(Rel);
2270   return getAnyRelocationLength(RE);
2271 }
2272 
2273 //
2274 // guessLibraryShortName() is passed a name of a dynamic library and returns a
2275 // guess on what the short name is.  Then name is returned as a substring of the
2276 // StringRef Name passed in.  The name of the dynamic library is recognized as
2277 // a framework if it has one of the two following forms:
2278 //      Foo.framework/Versions/A/Foo
2279 //      Foo.framework/Foo
2280 // Where A and Foo can be any string.  And may contain a trailing suffix
2281 // starting with an underbar.  If the Name is recognized as a framework then
2282 // isFramework is set to true else it is set to false.  If the Name has a
2283 // suffix then Suffix is set to the substring in Name that contains the suffix
2284 // else it is set to a NULL StringRef.
2285 //
2286 // The Name of the dynamic library is recognized as a library name if it has
2287 // one of the two following forms:
2288 //      libFoo.A.dylib
2289 //      libFoo.dylib
2290 //
2291 // The library may have a suffix trailing the name Foo of the form:
2292 //      libFoo_profile.A.dylib
2293 //      libFoo_profile.dylib
2294 // These dyld image suffixes are separated from the short name by a '_'
2295 // character. Because the '_' character is commonly used to separate words in
2296 // filenames guessLibraryShortName() cannot reliably separate a dylib's short
2297 // name from an arbitrary image suffix; imagine if both the short name and the
2298 // suffix contains an '_' character! To better deal with this ambiguity,
2299 // guessLibraryShortName() will recognize only "_debug" and "_profile" as valid
2300 // Suffix values. Calling code needs to be tolerant of guessLibraryShortName()
2301 // guessing incorrectly.
2302 //
2303 // The Name of the dynamic library is also recognized as a library name if it
2304 // has the following form:
2305 //      Foo.qtx
2306 //
2307 // If the Name of the dynamic library is none of the forms above then a NULL
2308 // StringRef is returned.
2309 StringRef MachOObjectFile::guessLibraryShortName(StringRef Name,
2310                                                  bool &isFramework,
2311                                                  StringRef &Suffix) {
2312   StringRef Foo, F, DotFramework, V, Dylib, Lib, Dot, Qtx;
2313   size_t a, b, c, d, Idx;
2314 
2315   isFramework = false;
2316   Suffix = StringRef();
2317 
2318   // Pull off the last component and make Foo point to it
2319   a = Name.rfind('/');
2320   if (a == Name.npos || a == 0)
2321     goto guess_library;
2322   Foo = Name.slice(a+1, Name.npos);
2323 
2324   // Look for a suffix starting with a '_'
2325   Idx = Foo.rfind('_');
2326   if (Idx != Foo.npos && Foo.size() >= 2) {
2327     Suffix = Foo.slice(Idx, Foo.npos);
2328     if (Suffix != "_debug" && Suffix != "_profile")
2329       Suffix = StringRef();
2330     else
2331       Foo = Foo.slice(0, Idx);
2332   }
2333 
2334   // First look for the form Foo.framework/Foo
2335   b = Name.rfind('/', a);
2336   if (b == Name.npos)
2337     Idx = 0;
2338   else
2339     Idx = b+1;
2340   F = Name.slice(Idx, Idx + Foo.size());
2341   DotFramework = Name.slice(Idx + Foo.size(),
2342                             Idx + Foo.size() + sizeof(".framework/")-1);
2343   if (F == Foo && DotFramework == ".framework/") {
2344     isFramework = true;
2345     return Foo;
2346   }
2347 
2348   // Next look for the form Foo.framework/Versions/A/Foo
2349   if (b == Name.npos)
2350     goto guess_library;
2351   c =  Name.rfind('/', b);
2352   if (c == Name.npos || c == 0)
2353     goto guess_library;
2354   V = Name.slice(c+1, Name.npos);
2355   if (!V.startswith("Versions/"))
2356     goto guess_library;
2357   d =  Name.rfind('/', c);
2358   if (d == Name.npos)
2359     Idx = 0;
2360   else
2361     Idx = d+1;
2362   F = Name.slice(Idx, Idx + Foo.size());
2363   DotFramework = Name.slice(Idx + Foo.size(),
2364                             Idx + Foo.size() + sizeof(".framework/")-1);
2365   if (F == Foo && DotFramework == ".framework/") {
2366     isFramework = true;
2367     return Foo;
2368   }
2369 
2370 guess_library:
2371   // pull off the suffix after the "." and make a point to it
2372   a = Name.rfind('.');
2373   if (a == Name.npos || a == 0)
2374     return StringRef();
2375   Dylib = Name.slice(a, Name.npos);
2376   if (Dylib != ".dylib")
2377     goto guess_qtx;
2378 
2379   // First pull off the version letter for the form Foo.A.dylib if any.
2380   if (a >= 3) {
2381     Dot = Name.slice(a-2, a-1);
2382     if (Dot == ".")
2383       a = a - 2;
2384   }
2385 
2386   b = Name.rfind('/', a);
2387   if (b == Name.npos)
2388     b = 0;
2389   else
2390     b = b+1;
2391   // ignore any suffix after an underbar like Foo_profile.A.dylib
2392   Idx = Name.rfind('_');
2393   if (Idx != Name.npos && Idx != b) {
2394     Lib = Name.slice(b, Idx);
2395     Suffix = Name.slice(Idx, a);
2396     if (Suffix != "_debug" && Suffix != "_profile") {
2397       Suffix = StringRef();
2398       Lib = Name.slice(b, a);
2399     }
2400   }
2401   else
2402     Lib = Name.slice(b, a);
2403   // There are incorrect library names of the form:
2404   // libATS.A_profile.dylib so check for these.
2405   if (Lib.size() >= 3) {
2406     Dot = Lib.slice(Lib.size()-2, Lib.size()-1);
2407     if (Dot == ".")
2408       Lib = Lib.slice(0, Lib.size()-2);
2409   }
2410   return Lib;
2411 
2412 guess_qtx:
2413   Qtx = Name.slice(a, Name.npos);
2414   if (Qtx != ".qtx")
2415     return StringRef();
2416   b = Name.rfind('/', a);
2417   if (b == Name.npos)
2418     Lib = Name.slice(0, a);
2419   else
2420     Lib = Name.slice(b+1, a);
2421   // There are library names of the form: QT.A.qtx so check for these.
2422   if (Lib.size() >= 3) {
2423     Dot = Lib.slice(Lib.size()-2, Lib.size()-1);
2424     if (Dot == ".")
2425       Lib = Lib.slice(0, Lib.size()-2);
2426   }
2427   return Lib;
2428 }
2429 
2430 // getLibraryShortNameByIndex() is used to get the short name of the library
2431 // for an undefined symbol in a linked Mach-O binary that was linked with the
2432 // normal two-level namespace default (that is MH_TWOLEVEL in the header).
2433 // It is passed the index (0 - based) of the library as translated from
2434 // GET_LIBRARY_ORDINAL (1 - based).
2435 std::error_code MachOObjectFile::getLibraryShortNameByIndex(unsigned Index,
2436                                                          StringRef &Res) const {
2437   if (Index >= Libraries.size())
2438     return object_error::parse_failed;
2439 
2440   // If the cache of LibrariesShortNames is not built up do that first for
2441   // all the Libraries.
2442   if (LibrariesShortNames.size() == 0) {
2443     for (unsigned i = 0; i < Libraries.size(); i++) {
2444       auto CommandOrErr =
2445         getStructOrErr<MachO::dylib_command>(*this, Libraries[i]);
2446       if (!CommandOrErr)
2447         return object_error::parse_failed;
2448       MachO::dylib_command D = CommandOrErr.get();
2449       if (D.dylib.name >= D.cmdsize)
2450         return object_error::parse_failed;
2451       const char *P = (const char *)(Libraries[i]) + D.dylib.name;
2452       StringRef Name = StringRef(P);
2453       if (D.dylib.name+Name.size() >= D.cmdsize)
2454         return object_error::parse_failed;
2455       StringRef Suffix;
2456       bool isFramework;
2457       StringRef shortName = guessLibraryShortName(Name, isFramework, Suffix);
2458       if (shortName.empty())
2459         LibrariesShortNames.push_back(Name);
2460       else
2461         LibrariesShortNames.push_back(shortName);
2462     }
2463   }
2464 
2465   Res = LibrariesShortNames[Index];
2466   return std::error_code();
2467 }
2468 
2469 uint32_t MachOObjectFile::getLibraryCount() const {
2470   return Libraries.size();
2471 }
2472 
2473 section_iterator
2474 MachOObjectFile::getRelocationRelocatedSection(relocation_iterator Rel) const {
2475   DataRefImpl Sec;
2476   Sec.d.a = Rel->getRawDataRefImpl().d.a;
2477   return section_iterator(SectionRef(Sec, this));
2478 }
2479 
2480 basic_symbol_iterator MachOObjectFile::symbol_begin() const {
2481   DataRefImpl DRI;
2482   MachO::symtab_command Symtab = getSymtabLoadCommand();
2483   if (!SymtabLoadCmd || Symtab.nsyms == 0)
2484     return basic_symbol_iterator(SymbolRef(DRI, this));
2485 
2486   return getSymbolByIndex(0);
2487 }
2488 
2489 basic_symbol_iterator MachOObjectFile::symbol_end() const {
2490   DataRefImpl DRI;
2491   MachO::symtab_command Symtab = getSymtabLoadCommand();
2492   if (!SymtabLoadCmd || Symtab.nsyms == 0)
2493     return basic_symbol_iterator(SymbolRef(DRI, this));
2494 
2495   unsigned SymbolTableEntrySize = is64Bit() ?
2496     sizeof(MachO::nlist_64) :
2497     sizeof(MachO::nlist);
2498   unsigned Offset = Symtab.symoff +
2499     Symtab.nsyms * SymbolTableEntrySize;
2500   DRI.p = reinterpret_cast<uintptr_t>(getPtr(*this, Offset));
2501   return basic_symbol_iterator(SymbolRef(DRI, this));
2502 }
2503 
2504 symbol_iterator MachOObjectFile::getSymbolByIndex(unsigned Index) const {
2505   MachO::symtab_command Symtab = getSymtabLoadCommand();
2506   if (!SymtabLoadCmd || Index >= Symtab.nsyms)
2507     report_fatal_error("Requested symbol index is out of range.");
2508   unsigned SymbolTableEntrySize =
2509     is64Bit() ? sizeof(MachO::nlist_64) : sizeof(MachO::nlist);
2510   DataRefImpl DRI;
2511   DRI.p = reinterpret_cast<uintptr_t>(getPtr(*this, Symtab.symoff));
2512   DRI.p += Index * SymbolTableEntrySize;
2513   return basic_symbol_iterator(SymbolRef(DRI, this));
2514 }
2515 
2516 uint64_t MachOObjectFile::getSymbolIndex(DataRefImpl Symb) const {
2517   MachO::symtab_command Symtab = getSymtabLoadCommand();
2518   if (!SymtabLoadCmd)
2519     report_fatal_error("getSymbolIndex() called with no symbol table symbol");
2520   unsigned SymbolTableEntrySize =
2521     is64Bit() ? sizeof(MachO::nlist_64) : sizeof(MachO::nlist);
2522   DataRefImpl DRIstart;
2523   DRIstart.p = reinterpret_cast<uintptr_t>(getPtr(*this, Symtab.symoff));
2524   uint64_t Index = (Symb.p - DRIstart.p) / SymbolTableEntrySize;
2525   return Index;
2526 }
2527 
2528 section_iterator MachOObjectFile::section_begin() const {
2529   DataRefImpl DRI;
2530   return section_iterator(SectionRef(DRI, this));
2531 }
2532 
2533 section_iterator MachOObjectFile::section_end() const {
2534   DataRefImpl DRI;
2535   DRI.d.a = Sections.size();
2536   return section_iterator(SectionRef(DRI, this));
2537 }
2538 
2539 uint8_t MachOObjectFile::getBytesInAddress() const {
2540   return is64Bit() ? 8 : 4;
2541 }
2542 
2543 StringRef MachOObjectFile::getFileFormatName() const {
2544   unsigned CPUType = getCPUType(*this);
2545   if (!is64Bit()) {
2546     switch (CPUType) {
2547     case MachO::CPU_TYPE_I386:
2548       return "Mach-O 32-bit i386";
2549     case MachO::CPU_TYPE_ARM:
2550       return "Mach-O arm";
2551     case MachO::CPU_TYPE_ARM64_32:
2552       return "Mach-O arm64 (ILP32)";
2553     case MachO::CPU_TYPE_POWERPC:
2554       return "Mach-O 32-bit ppc";
2555     default:
2556       return "Mach-O 32-bit unknown";
2557     }
2558   }
2559 
2560   switch (CPUType) {
2561   case MachO::CPU_TYPE_X86_64:
2562     return "Mach-O 64-bit x86-64";
2563   case MachO::CPU_TYPE_ARM64:
2564     return "Mach-O arm64";
2565   case MachO::CPU_TYPE_POWERPC64:
2566     return "Mach-O 64-bit ppc64";
2567   default:
2568     return "Mach-O 64-bit unknown";
2569   }
2570 }
2571 
2572 Triple::ArchType MachOObjectFile::getArch(uint32_t CPUType, uint32_t CPUSubType) {
2573   switch (CPUType) {
2574   case MachO::CPU_TYPE_I386:
2575     return Triple::x86;
2576   case MachO::CPU_TYPE_X86_64:
2577     return Triple::x86_64;
2578   case MachO::CPU_TYPE_ARM:
2579     return Triple::arm;
2580   case MachO::CPU_TYPE_ARM64:
2581     return Triple::aarch64;
2582   case MachO::CPU_TYPE_ARM64_32:
2583     return Triple::aarch64_32;
2584   case MachO::CPU_TYPE_POWERPC:
2585     return Triple::ppc;
2586   case MachO::CPU_TYPE_POWERPC64:
2587     return Triple::ppc64;
2588   default:
2589     return Triple::UnknownArch;
2590   }
2591 }
2592 
2593 Triple MachOObjectFile::getArchTriple(uint32_t CPUType, uint32_t CPUSubType,
2594                                       const char **McpuDefault,
2595                                       const char **ArchFlag) {
2596   if (McpuDefault)
2597     *McpuDefault = nullptr;
2598   if (ArchFlag)
2599     *ArchFlag = nullptr;
2600 
2601   switch (CPUType) {
2602   case MachO::CPU_TYPE_I386:
2603     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
2604     case MachO::CPU_SUBTYPE_I386_ALL:
2605       if (ArchFlag)
2606         *ArchFlag = "i386";
2607       return Triple("i386-apple-darwin");
2608     default:
2609       return Triple();
2610     }
2611   case MachO::CPU_TYPE_X86_64:
2612     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
2613     case MachO::CPU_SUBTYPE_X86_64_ALL:
2614       if (ArchFlag)
2615         *ArchFlag = "x86_64";
2616       return Triple("x86_64-apple-darwin");
2617     case MachO::CPU_SUBTYPE_X86_64_H:
2618       if (ArchFlag)
2619         *ArchFlag = "x86_64h";
2620       return Triple("x86_64h-apple-darwin");
2621     default:
2622       return Triple();
2623     }
2624   case MachO::CPU_TYPE_ARM:
2625     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
2626     case MachO::CPU_SUBTYPE_ARM_V4T:
2627       if (ArchFlag)
2628         *ArchFlag = "armv4t";
2629       return Triple("armv4t-apple-darwin");
2630     case MachO::CPU_SUBTYPE_ARM_V5TEJ:
2631       if (ArchFlag)
2632         *ArchFlag = "armv5e";
2633       return Triple("armv5e-apple-darwin");
2634     case MachO::CPU_SUBTYPE_ARM_XSCALE:
2635       if (ArchFlag)
2636         *ArchFlag = "xscale";
2637       return Triple("xscale-apple-darwin");
2638     case MachO::CPU_SUBTYPE_ARM_V6:
2639       if (ArchFlag)
2640         *ArchFlag = "armv6";
2641       return Triple("armv6-apple-darwin");
2642     case MachO::CPU_SUBTYPE_ARM_V6M:
2643       if (McpuDefault)
2644         *McpuDefault = "cortex-m0";
2645       if (ArchFlag)
2646         *ArchFlag = "armv6m";
2647       return Triple("armv6m-apple-darwin");
2648     case MachO::CPU_SUBTYPE_ARM_V7:
2649       if (ArchFlag)
2650         *ArchFlag = "armv7";
2651       return Triple("armv7-apple-darwin");
2652     case MachO::CPU_SUBTYPE_ARM_V7EM:
2653       if (McpuDefault)
2654         *McpuDefault = "cortex-m4";
2655       if (ArchFlag)
2656         *ArchFlag = "armv7em";
2657       return Triple("thumbv7em-apple-darwin");
2658     case MachO::CPU_SUBTYPE_ARM_V7K:
2659       if (McpuDefault)
2660         *McpuDefault = "cortex-a7";
2661       if (ArchFlag)
2662         *ArchFlag = "armv7k";
2663       return Triple("armv7k-apple-darwin");
2664     case MachO::CPU_SUBTYPE_ARM_V7M:
2665       if (McpuDefault)
2666         *McpuDefault = "cortex-m3";
2667       if (ArchFlag)
2668         *ArchFlag = "armv7m";
2669       return Triple("thumbv7m-apple-darwin");
2670     case MachO::CPU_SUBTYPE_ARM_V7S:
2671       if (McpuDefault)
2672         *McpuDefault = "cortex-a7";
2673       if (ArchFlag)
2674         *ArchFlag = "armv7s";
2675       return Triple("armv7s-apple-darwin");
2676     default:
2677       return Triple();
2678     }
2679   case MachO::CPU_TYPE_ARM64:
2680     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
2681     case MachO::CPU_SUBTYPE_ARM64_ALL:
2682       if (McpuDefault)
2683         *McpuDefault = "cyclone";
2684       if (ArchFlag)
2685         *ArchFlag = "arm64";
2686       return Triple("arm64-apple-darwin");
2687     default:
2688       return Triple();
2689     }
2690   case MachO::CPU_TYPE_ARM64_32:
2691     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
2692     case MachO::CPU_SUBTYPE_ARM64_32_V8:
2693       if (McpuDefault)
2694         *McpuDefault = "cyclone";
2695       if (ArchFlag)
2696         *ArchFlag = "arm64_32";
2697       return Triple("arm64_32-apple-darwin");
2698     default:
2699       return Triple();
2700     }
2701   case MachO::CPU_TYPE_POWERPC:
2702     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
2703     case MachO::CPU_SUBTYPE_POWERPC_ALL:
2704       if (ArchFlag)
2705         *ArchFlag = "ppc";
2706       return Triple("ppc-apple-darwin");
2707     default:
2708       return Triple();
2709     }
2710   case MachO::CPU_TYPE_POWERPC64:
2711     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
2712     case MachO::CPU_SUBTYPE_POWERPC_ALL:
2713       if (ArchFlag)
2714         *ArchFlag = "ppc64";
2715       return Triple("ppc64-apple-darwin");
2716     default:
2717       return Triple();
2718     }
2719   default:
2720     return Triple();
2721   }
2722 }
2723 
2724 Triple MachOObjectFile::getHostArch() {
2725   return Triple(sys::getDefaultTargetTriple());
2726 }
2727 
2728 bool MachOObjectFile::isValidArch(StringRef ArchFlag) {
2729   auto validArchs = getValidArchs();
2730   return llvm::find(validArchs, ArchFlag) != validArchs.end();
2731 }
2732 
2733 ArrayRef<StringRef> MachOObjectFile::getValidArchs() {
2734   static const std::array<StringRef, 17> validArchs = {{
2735       "i386",   "x86_64", "x86_64h",  "armv4t",  "arm",    "armv5e",
2736       "armv6",  "armv6m", "armv7",    "armv7em", "armv7k", "armv7m",
2737       "armv7s", "arm64",  "arm64_32", "ppc",     "ppc64",
2738   }};
2739 
2740   return validArchs;
2741 }
2742 
2743 Triple::ArchType MachOObjectFile::getArch() const {
2744   return getArch(getCPUType(*this), getCPUSubType(*this));
2745 }
2746 
2747 Triple MachOObjectFile::getArchTriple(const char **McpuDefault) const {
2748   return getArchTriple(Header.cputype, Header.cpusubtype, McpuDefault);
2749 }
2750 
2751 relocation_iterator MachOObjectFile::section_rel_begin(unsigned Index) const {
2752   DataRefImpl DRI;
2753   DRI.d.a = Index;
2754   return section_rel_begin(DRI);
2755 }
2756 
2757 relocation_iterator MachOObjectFile::section_rel_end(unsigned Index) const {
2758   DataRefImpl DRI;
2759   DRI.d.a = Index;
2760   return section_rel_end(DRI);
2761 }
2762 
2763 dice_iterator MachOObjectFile::begin_dices() const {
2764   DataRefImpl DRI;
2765   if (!DataInCodeLoadCmd)
2766     return dice_iterator(DiceRef(DRI, this));
2767 
2768   MachO::linkedit_data_command DicLC = getDataInCodeLoadCommand();
2769   DRI.p = reinterpret_cast<uintptr_t>(getPtr(*this, DicLC.dataoff));
2770   return dice_iterator(DiceRef(DRI, this));
2771 }
2772 
2773 dice_iterator MachOObjectFile::end_dices() const {
2774   DataRefImpl DRI;
2775   if (!DataInCodeLoadCmd)
2776     return dice_iterator(DiceRef(DRI, this));
2777 
2778   MachO::linkedit_data_command DicLC = getDataInCodeLoadCommand();
2779   unsigned Offset = DicLC.dataoff + DicLC.datasize;
2780   DRI.p = reinterpret_cast<uintptr_t>(getPtr(*this, Offset));
2781   return dice_iterator(DiceRef(DRI, this));
2782 }
2783 
2784 ExportEntry::ExportEntry(Error *E, const MachOObjectFile *O,
2785                          ArrayRef<uint8_t> T) : E(E), O(O), Trie(T) {}
2786 
2787 void ExportEntry::moveToFirst() {
2788   ErrorAsOutParameter ErrAsOutParam(E);
2789   pushNode(0);
2790   if (*E)
2791     return;
2792   pushDownUntilBottom();
2793 }
2794 
2795 void ExportEntry::moveToEnd() {
2796   Stack.clear();
2797   Done = true;
2798 }
2799 
2800 bool ExportEntry::operator==(const ExportEntry &Other) const {
2801   // Common case, one at end, other iterating from begin.
2802   if (Done || Other.Done)
2803     return (Done == Other.Done);
2804   // Not equal if different stack sizes.
2805   if (Stack.size() != Other.Stack.size())
2806     return false;
2807   // Not equal if different cumulative strings.
2808   if (!CumulativeString.equals(Other.CumulativeString))
2809     return false;
2810   // Equal if all nodes in both stacks match.
2811   for (unsigned i=0; i < Stack.size(); ++i) {
2812     if (Stack[i].Start != Other.Stack[i].Start)
2813       return false;
2814   }
2815   return true;
2816 }
2817 
2818 uint64_t ExportEntry::readULEB128(const uint8_t *&Ptr, const char **error) {
2819   unsigned Count;
2820   uint64_t Result = decodeULEB128(Ptr, &Count, Trie.end(), error);
2821   Ptr += Count;
2822   if (Ptr > Trie.end())
2823     Ptr = Trie.end();
2824   return Result;
2825 }
2826 
2827 StringRef ExportEntry::name() const {
2828   return CumulativeString;
2829 }
2830 
2831 uint64_t ExportEntry::flags() const {
2832   return Stack.back().Flags;
2833 }
2834 
2835 uint64_t ExportEntry::address() const {
2836   return Stack.back().Address;
2837 }
2838 
2839 uint64_t ExportEntry::other() const {
2840   return Stack.back().Other;
2841 }
2842 
2843 StringRef ExportEntry::otherName() const {
2844   const char* ImportName = Stack.back().ImportName;
2845   if (ImportName)
2846     return StringRef(ImportName);
2847   return StringRef();
2848 }
2849 
2850 uint32_t ExportEntry::nodeOffset() const {
2851   return Stack.back().Start - Trie.begin();
2852 }
2853 
2854 ExportEntry::NodeState::NodeState(const uint8_t *Ptr)
2855     : Start(Ptr), Current(Ptr) {}
2856 
2857 void ExportEntry::pushNode(uint64_t offset) {
2858   ErrorAsOutParameter ErrAsOutParam(E);
2859   const uint8_t *Ptr = Trie.begin() + offset;
2860   NodeState State(Ptr);
2861   const char *error;
2862   uint64_t ExportInfoSize = readULEB128(State.Current, &error);
2863   if (error) {
2864     *E = malformedError("export info size " + Twine(error) +
2865                         " in export trie data at node: 0x" +
2866                         Twine::utohexstr(offset));
2867     moveToEnd();
2868     return;
2869   }
2870   State.IsExportNode = (ExportInfoSize != 0);
2871   const uint8_t* Children = State.Current + ExportInfoSize;
2872   if (Children > Trie.end()) {
2873     *E = malformedError(
2874         "export info size: 0x" + Twine::utohexstr(ExportInfoSize) +
2875         " in export trie data at node: 0x" + Twine::utohexstr(offset) +
2876         " too big and extends past end of trie data");
2877     moveToEnd();
2878     return;
2879   }
2880   if (State.IsExportNode) {
2881     const uint8_t *ExportStart = State.Current;
2882     State.Flags = readULEB128(State.Current, &error);
2883     if (error) {
2884       *E = malformedError("flags " + Twine(error) +
2885                           " in export trie data at node: 0x" +
2886                           Twine::utohexstr(offset));
2887       moveToEnd();
2888       return;
2889     }
2890     uint64_t Kind = State.Flags & MachO::EXPORT_SYMBOL_FLAGS_KIND_MASK;
2891     if (State.Flags != 0 &&
2892         (Kind != MachO::EXPORT_SYMBOL_FLAGS_KIND_REGULAR &&
2893          Kind != MachO::EXPORT_SYMBOL_FLAGS_KIND_ABSOLUTE &&
2894          Kind != MachO::EXPORT_SYMBOL_FLAGS_KIND_THREAD_LOCAL)) {
2895       *E = malformedError(
2896           "unsupported exported symbol kind: " + Twine((int)Kind) +
2897           " in flags: 0x" + Twine::utohexstr(State.Flags) +
2898           " in export trie data at node: 0x" + Twine::utohexstr(offset));
2899       moveToEnd();
2900       return;
2901     }
2902     if (State.Flags & MachO::EXPORT_SYMBOL_FLAGS_REEXPORT) {
2903       State.Address = 0;
2904       State.Other = readULEB128(State.Current, &error); // dylib ordinal
2905       if (error) {
2906         *E = malformedError("dylib ordinal of re-export " + Twine(error) +
2907                             " in export trie data at node: 0x" +
2908                             Twine::utohexstr(offset));
2909         moveToEnd();
2910         return;
2911       }
2912       if (O != nullptr) {
2913         if (State.Other > O->getLibraryCount()) {
2914           *E = malformedError(
2915               "bad library ordinal: " + Twine((int)State.Other) + " (max " +
2916               Twine((int)O->getLibraryCount()) +
2917               ") in export trie data at node: 0x" + Twine::utohexstr(offset));
2918           moveToEnd();
2919           return;
2920         }
2921       }
2922       State.ImportName = reinterpret_cast<const char*>(State.Current);
2923       if (*State.ImportName == '\0') {
2924         State.Current++;
2925       } else {
2926         const uint8_t *End = State.Current + 1;
2927         if (End >= Trie.end()) {
2928           *E = malformedError("import name of re-export in export trie data at "
2929                               "node: 0x" +
2930                               Twine::utohexstr(offset) +
2931                               " starts past end of trie data");
2932           moveToEnd();
2933           return;
2934         }
2935         while(*End != '\0' && End < Trie.end())
2936           End++;
2937         if (*End != '\0') {
2938           *E = malformedError("import name of re-export in export trie data at "
2939                               "node: 0x" +
2940                               Twine::utohexstr(offset) +
2941                               " extends past end of trie data");
2942           moveToEnd();
2943           return;
2944         }
2945         State.Current = End + 1;
2946       }
2947     } else {
2948       State.Address = readULEB128(State.Current, &error);
2949       if (error) {
2950         *E = malformedError("address " + Twine(error) +
2951                             " in export trie data at node: 0x" +
2952                             Twine::utohexstr(offset));
2953         moveToEnd();
2954         return;
2955       }
2956       if (State.Flags & MachO::EXPORT_SYMBOL_FLAGS_STUB_AND_RESOLVER) {
2957         State.Other = readULEB128(State.Current, &error);
2958         if (error) {
2959           *E = malformedError("resolver of stub and resolver " + Twine(error) +
2960                               " in export trie data at node: 0x" +
2961                               Twine::utohexstr(offset));
2962           moveToEnd();
2963           return;
2964         }
2965       }
2966     }
2967     if(ExportStart + ExportInfoSize != State.Current) {
2968       *E = malformedError(
2969           "inconsistant export info size: 0x" +
2970           Twine::utohexstr(ExportInfoSize) + " where actual size was: 0x" +
2971           Twine::utohexstr(State.Current - ExportStart) +
2972           " in export trie data at node: 0x" + Twine::utohexstr(offset));
2973       moveToEnd();
2974       return;
2975     }
2976   }
2977   State.ChildCount = *Children;
2978   if (State.ChildCount != 0 && Children + 1 >= Trie.end()) {
2979     *E = malformedError("byte for count of childern in export trie data at "
2980                         "node: 0x" +
2981                         Twine::utohexstr(offset) +
2982                         " extends past end of trie data");
2983     moveToEnd();
2984     return;
2985   }
2986   State.Current = Children + 1;
2987   State.NextChildIndex = 0;
2988   State.ParentStringLength = CumulativeString.size();
2989   Stack.push_back(State);
2990 }
2991 
2992 void ExportEntry::pushDownUntilBottom() {
2993   ErrorAsOutParameter ErrAsOutParam(E);
2994   const char *error;
2995   while (Stack.back().NextChildIndex < Stack.back().ChildCount) {
2996     NodeState &Top = Stack.back();
2997     CumulativeString.resize(Top.ParentStringLength);
2998     for (;*Top.Current != 0 && Top.Current < Trie.end(); Top.Current++) {
2999       char C = *Top.Current;
3000       CumulativeString.push_back(C);
3001     }
3002     if (Top.Current >= Trie.end()) {
3003       *E = malformedError("edge sub-string in export trie data at node: 0x" +
3004                           Twine::utohexstr(Top.Start - Trie.begin()) +
3005                           " for child #" + Twine((int)Top.NextChildIndex) +
3006                           " extends past end of trie data");
3007       moveToEnd();
3008       return;
3009     }
3010     Top.Current += 1;
3011     uint64_t childNodeIndex = readULEB128(Top.Current, &error);
3012     if (error) {
3013       *E = malformedError("child node offset " + Twine(error) +
3014                           " in export trie data at node: 0x" +
3015                           Twine::utohexstr(Top.Start - Trie.begin()));
3016       moveToEnd();
3017       return;
3018     }
3019     for (const NodeState &node : nodes()) {
3020       if (node.Start == Trie.begin() + childNodeIndex){
3021         *E = malformedError("loop in childern in export trie data at node: 0x" +
3022                             Twine::utohexstr(Top.Start - Trie.begin()) +
3023                             " back to node: 0x" +
3024                             Twine::utohexstr(childNodeIndex));
3025         moveToEnd();
3026         return;
3027       }
3028     }
3029     Top.NextChildIndex += 1;
3030     pushNode(childNodeIndex);
3031     if (*E)
3032       return;
3033   }
3034   if (!Stack.back().IsExportNode) {
3035     *E = malformedError("node is not an export node in export trie data at "
3036                         "node: 0x" +
3037                         Twine::utohexstr(Stack.back().Start - Trie.begin()));
3038     moveToEnd();
3039     return;
3040   }
3041 }
3042 
3043 // We have a trie data structure and need a way to walk it that is compatible
3044 // with the C++ iterator model. The solution is a non-recursive depth first
3045 // traversal where the iterator contains a stack of parent nodes along with a
3046 // string that is the accumulation of all edge strings along the parent chain
3047 // to this point.
3048 //
3049 // There is one "export" node for each exported symbol.  But because some
3050 // symbols may be a prefix of another symbol (e.g. _dup and _dup2), an export
3051 // node may have child nodes too.
3052 //
3053 // The algorithm for moveNext() is to keep moving down the leftmost unvisited
3054 // child until hitting a node with no children (which is an export node or
3055 // else the trie is malformed). On the way down, each node is pushed on the
3056 // stack ivar.  If there is no more ways down, it pops up one and tries to go
3057 // down a sibling path until a childless node is reached.
3058 void ExportEntry::moveNext() {
3059   assert(!Stack.empty() && "ExportEntry::moveNext() with empty node stack");
3060   if (!Stack.back().IsExportNode) {
3061     *E = malformedError("node is not an export node in export trie data at "
3062                         "node: 0x" +
3063                         Twine::utohexstr(Stack.back().Start - Trie.begin()));
3064     moveToEnd();
3065     return;
3066   }
3067 
3068   Stack.pop_back();
3069   while (!Stack.empty()) {
3070     NodeState &Top = Stack.back();
3071     if (Top.NextChildIndex < Top.ChildCount) {
3072       pushDownUntilBottom();
3073       // Now at the next export node.
3074       return;
3075     } else {
3076       if (Top.IsExportNode) {
3077         // This node has no children but is itself an export node.
3078         CumulativeString.resize(Top.ParentStringLength);
3079         return;
3080       }
3081       Stack.pop_back();
3082     }
3083   }
3084   Done = true;
3085 }
3086 
3087 iterator_range<export_iterator>
3088 MachOObjectFile::exports(Error &E, ArrayRef<uint8_t> Trie,
3089                          const MachOObjectFile *O) {
3090   ExportEntry Start(&E, O, Trie);
3091   if (Trie.empty())
3092     Start.moveToEnd();
3093   else
3094     Start.moveToFirst();
3095 
3096   ExportEntry Finish(&E, O, Trie);
3097   Finish.moveToEnd();
3098 
3099   return make_range(export_iterator(Start), export_iterator(Finish));
3100 }
3101 
3102 iterator_range<export_iterator> MachOObjectFile::exports(Error &Err) const {
3103   return exports(Err, getDyldInfoExportsTrie(), this);
3104 }
3105 
3106 MachORebaseEntry::MachORebaseEntry(Error *E, const MachOObjectFile *O,
3107                                    ArrayRef<uint8_t> Bytes, bool is64Bit)
3108     : E(E), O(O), Opcodes(Bytes), Ptr(Bytes.begin()),
3109       PointerSize(is64Bit ? 8 : 4) {}
3110 
3111 void MachORebaseEntry::moveToFirst() {
3112   Ptr = Opcodes.begin();
3113   moveNext();
3114 }
3115 
3116 void MachORebaseEntry::moveToEnd() {
3117   Ptr = Opcodes.end();
3118   RemainingLoopCount = 0;
3119   Done = true;
3120 }
3121 
3122 void MachORebaseEntry::moveNext() {
3123   ErrorAsOutParameter ErrAsOutParam(E);
3124   // If in the middle of some loop, move to next rebasing in loop.
3125   SegmentOffset += AdvanceAmount;
3126   if (RemainingLoopCount) {
3127     --RemainingLoopCount;
3128     return;
3129   }
3130   // REBASE_OPCODE_DONE is only used for padding if we are not aligned to
3131   // pointer size. Therefore it is possible to reach the end without ever having
3132   // seen REBASE_OPCODE_DONE.
3133   if (Ptr == Opcodes.end()) {
3134     Done = true;
3135     return;
3136   }
3137   bool More = true;
3138   while (More) {
3139     // Parse next opcode and set up next loop.
3140     const uint8_t *OpcodeStart = Ptr;
3141     uint8_t Byte = *Ptr++;
3142     uint8_t ImmValue = Byte & MachO::REBASE_IMMEDIATE_MASK;
3143     uint8_t Opcode = Byte & MachO::REBASE_OPCODE_MASK;
3144     uint32_t Count, Skip;
3145     const char *error = nullptr;
3146     switch (Opcode) {
3147     case MachO::REBASE_OPCODE_DONE:
3148       More = false;
3149       Done = true;
3150       moveToEnd();
3151       DEBUG_WITH_TYPE("mach-o-rebase", dbgs() << "REBASE_OPCODE_DONE\n");
3152       break;
3153     case MachO::REBASE_OPCODE_SET_TYPE_IMM:
3154       RebaseType = ImmValue;
3155       if (RebaseType > MachO::REBASE_TYPE_TEXT_PCREL32) {
3156         *E = malformedError("for REBASE_OPCODE_SET_TYPE_IMM bad bind type: " +
3157                             Twine((int)RebaseType) + " for opcode at: 0x" +
3158                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3159         moveToEnd();
3160         return;
3161       }
3162       DEBUG_WITH_TYPE(
3163           "mach-o-rebase",
3164           dbgs() << "REBASE_OPCODE_SET_TYPE_IMM: "
3165                  << "RebaseType=" << (int) RebaseType << "\n");
3166       break;
3167     case MachO::REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
3168       SegmentIndex = ImmValue;
3169       SegmentOffset = readULEB128(&error);
3170       if (error) {
3171         *E = malformedError("for REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB " +
3172                             Twine(error) + " for opcode at: 0x" +
3173                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3174         moveToEnd();
3175         return;
3176       }
3177       error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3178                                                PointerSize);
3179       if (error) {
3180         *E = malformedError("for REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB " +
3181                             Twine(error) + " for opcode at: 0x" +
3182                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3183         moveToEnd();
3184         return;
3185       }
3186       DEBUG_WITH_TYPE(
3187           "mach-o-rebase",
3188           dbgs() << "REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB: "
3189                  << "SegmentIndex=" << SegmentIndex << ", "
3190                  << format("SegmentOffset=0x%06X", SegmentOffset)
3191                  << "\n");
3192       break;
3193     case MachO::REBASE_OPCODE_ADD_ADDR_ULEB:
3194       SegmentOffset += readULEB128(&error);
3195       if (error) {
3196         *E = malformedError("for REBASE_OPCODE_ADD_ADDR_ULEB " + Twine(error) +
3197                             " for opcode at: 0x" +
3198                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3199         moveToEnd();
3200         return;
3201       }
3202       error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3203                                                PointerSize);
3204       if (error) {
3205         *E = malformedError("for REBASE_OPCODE_ADD_ADDR_ULEB " + Twine(error) +
3206                             " for opcode at: 0x" +
3207                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3208         moveToEnd();
3209         return;
3210       }
3211       DEBUG_WITH_TYPE("mach-o-rebase",
3212                       dbgs() << "REBASE_OPCODE_ADD_ADDR_ULEB: "
3213                              << format("SegmentOffset=0x%06X",
3214                                        SegmentOffset) << "\n");
3215       break;
3216     case MachO::REBASE_OPCODE_ADD_ADDR_IMM_SCALED:
3217       error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3218                                                PointerSize);
3219       if (error) {
3220         *E = malformedError("for REBASE_OPCODE_ADD_ADDR_IMM_SCALED " +
3221                             Twine(error) + " for opcode at: 0x" +
3222                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3223         moveToEnd();
3224         return;
3225       }
3226       SegmentOffset += ImmValue * PointerSize;
3227       error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3228                                                PointerSize);
3229       if (error) {
3230         *E =
3231             malformedError("for REBASE_OPCODE_ADD_ADDR_IMM_SCALED "
3232                            " (after adding immediate times the pointer size) " +
3233                            Twine(error) + " for opcode at: 0x" +
3234                            Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3235         moveToEnd();
3236         return;
3237       }
3238       DEBUG_WITH_TYPE("mach-o-rebase",
3239                       dbgs() << "REBASE_OPCODE_ADD_ADDR_IMM_SCALED: "
3240                              << format("SegmentOffset=0x%06X",
3241                                        SegmentOffset) << "\n");
3242       break;
3243     case MachO::REBASE_OPCODE_DO_REBASE_IMM_TIMES:
3244       AdvanceAmount = PointerSize;
3245       Skip = 0;
3246       Count = ImmValue;
3247       if (ImmValue != 0)
3248         RemainingLoopCount = ImmValue - 1;
3249       else
3250         RemainingLoopCount = 0;
3251       error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3252                                                PointerSize, Count, Skip);
3253       if (error) {
3254         *E = malformedError("for REBASE_OPCODE_DO_REBASE_IMM_TIMES " +
3255                             Twine(error) + " for opcode at: 0x" +
3256                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3257         moveToEnd();
3258         return;
3259       }
3260       DEBUG_WITH_TYPE(
3261           "mach-o-rebase",
3262           dbgs() << "REBASE_OPCODE_DO_REBASE_IMM_TIMES: "
3263                  << format("SegmentOffset=0x%06X", SegmentOffset)
3264                  << ", AdvanceAmount=" << AdvanceAmount
3265                  << ", RemainingLoopCount=" << RemainingLoopCount
3266                  << "\n");
3267       return;
3268     case MachO::REBASE_OPCODE_DO_REBASE_ULEB_TIMES:
3269       AdvanceAmount = PointerSize;
3270       Skip = 0;
3271       Count = readULEB128(&error);
3272       if (error) {
3273         *E = malformedError("for REBASE_OPCODE_DO_REBASE_ULEB_TIMES " +
3274                             Twine(error) + " for opcode at: 0x" +
3275                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3276         moveToEnd();
3277         return;
3278       }
3279       if (Count != 0)
3280         RemainingLoopCount = Count - 1;
3281       else
3282         RemainingLoopCount = 0;
3283       error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3284                                                PointerSize, Count, Skip);
3285       if (error) {
3286         *E = malformedError("for REBASE_OPCODE_DO_REBASE_ULEB_TIMES " +
3287                             Twine(error) + " for opcode at: 0x" +
3288                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3289         moveToEnd();
3290         return;
3291       }
3292       DEBUG_WITH_TYPE(
3293           "mach-o-rebase",
3294           dbgs() << "REBASE_OPCODE_DO_REBASE_ULEB_TIMES: "
3295                  << format("SegmentOffset=0x%06X", SegmentOffset)
3296                  << ", AdvanceAmount=" << AdvanceAmount
3297                  << ", RemainingLoopCount=" << RemainingLoopCount
3298                  << "\n");
3299       return;
3300     case MachO::REBASE_OPCODE_DO_REBASE_ADD_ADDR_ULEB:
3301       Skip = readULEB128(&error);
3302       if (error) {
3303         *E = malformedError("for REBASE_OPCODE_DO_REBASE_ADD_ADDR_ULEB " +
3304                             Twine(error) + " for opcode at: 0x" +
3305                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3306         moveToEnd();
3307         return;
3308       }
3309       AdvanceAmount = Skip + PointerSize;
3310       Count = 1;
3311       RemainingLoopCount = 0;
3312       error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3313                                                PointerSize, Count, Skip);
3314       if (error) {
3315         *E = malformedError("for REBASE_OPCODE_DO_REBASE_ADD_ADDR_ULEB " +
3316                             Twine(error) + " for opcode at: 0x" +
3317                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3318         moveToEnd();
3319         return;
3320       }
3321       DEBUG_WITH_TYPE(
3322           "mach-o-rebase",
3323           dbgs() << "REBASE_OPCODE_DO_REBASE_ADD_ADDR_ULEB: "
3324                  << format("SegmentOffset=0x%06X", SegmentOffset)
3325                  << ", AdvanceAmount=" << AdvanceAmount
3326                  << ", RemainingLoopCount=" << RemainingLoopCount
3327                  << "\n");
3328       return;
3329     case MachO::REBASE_OPCODE_DO_REBASE_ULEB_TIMES_SKIPPING_ULEB:
3330       Count = readULEB128(&error);
3331       if (error) {
3332         *E = malformedError("for REBASE_OPCODE_DO_REBASE_ULEB_TIMES_SKIPPING_"
3333                             "ULEB " +
3334                             Twine(error) + " for opcode at: 0x" +
3335                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3336         moveToEnd();
3337         return;
3338       }
3339       if (Count != 0)
3340         RemainingLoopCount = Count - 1;
3341       else
3342         RemainingLoopCount = 0;
3343       Skip = readULEB128(&error);
3344       if (error) {
3345         *E = malformedError("for REBASE_OPCODE_DO_REBASE_ULEB_TIMES_SKIPPING_"
3346                             "ULEB " +
3347                             Twine(error) + " for opcode at: 0x" +
3348                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3349         moveToEnd();
3350         return;
3351       }
3352       AdvanceAmount = Skip + PointerSize;
3353 
3354       error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3355                                                PointerSize, Count, Skip);
3356       if (error) {
3357         *E = malformedError("for REBASE_OPCODE_DO_REBASE_ULEB_TIMES_SKIPPING_"
3358                             "ULEB " +
3359                             Twine(error) + " for opcode at: 0x" +
3360                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3361         moveToEnd();
3362         return;
3363       }
3364       DEBUG_WITH_TYPE(
3365           "mach-o-rebase",
3366           dbgs() << "REBASE_OPCODE_DO_REBASE_ULEB_TIMES_SKIPPING_ULEB: "
3367                  << format("SegmentOffset=0x%06X", SegmentOffset)
3368                  << ", AdvanceAmount=" << AdvanceAmount
3369                  << ", RemainingLoopCount=" << RemainingLoopCount
3370                  << "\n");
3371       return;
3372     default:
3373       *E = malformedError("bad rebase info (bad opcode value 0x" +
3374                           Twine::utohexstr(Opcode) + " for opcode at: 0x" +
3375                           Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3376       moveToEnd();
3377       return;
3378     }
3379   }
3380 }
3381 
3382 uint64_t MachORebaseEntry::readULEB128(const char **error) {
3383   unsigned Count;
3384   uint64_t Result = decodeULEB128(Ptr, &Count, Opcodes.end(), error);
3385   Ptr += Count;
3386   if (Ptr > Opcodes.end())
3387     Ptr = Opcodes.end();
3388   return Result;
3389 }
3390 
3391 int32_t MachORebaseEntry::segmentIndex() const { return SegmentIndex; }
3392 
3393 uint64_t MachORebaseEntry::segmentOffset() const { return SegmentOffset; }
3394 
3395 StringRef MachORebaseEntry::typeName() const {
3396   switch (RebaseType) {
3397   case MachO::REBASE_TYPE_POINTER:
3398     return "pointer";
3399   case MachO::REBASE_TYPE_TEXT_ABSOLUTE32:
3400     return "text abs32";
3401   case MachO::REBASE_TYPE_TEXT_PCREL32:
3402     return "text rel32";
3403   }
3404   return "unknown";
3405 }
3406 
3407 // For use with the SegIndex of a checked Mach-O Rebase entry
3408 // to get the segment name.
3409 StringRef MachORebaseEntry::segmentName() const {
3410   return O->BindRebaseSegmentName(SegmentIndex);
3411 }
3412 
3413 // For use with a SegIndex,SegOffset pair from a checked Mach-O Rebase entry
3414 // to get the section name.
3415 StringRef MachORebaseEntry::sectionName() const {
3416   return O->BindRebaseSectionName(SegmentIndex, SegmentOffset);
3417 }
3418 
3419 // For use with a SegIndex,SegOffset pair from a checked Mach-O Rebase entry
3420 // to get the address.
3421 uint64_t MachORebaseEntry::address() const {
3422   return O->BindRebaseAddress(SegmentIndex, SegmentOffset);
3423 }
3424 
3425 bool MachORebaseEntry::operator==(const MachORebaseEntry &Other) const {
3426 #ifdef EXPENSIVE_CHECKS
3427   assert(Opcodes == Other.Opcodes && "compare iterators of different files");
3428 #else
3429   assert(Opcodes.data() == Other.Opcodes.data() && "compare iterators of different files");
3430 #endif
3431   return (Ptr == Other.Ptr) &&
3432          (RemainingLoopCount == Other.RemainingLoopCount) &&
3433          (Done == Other.Done);
3434 }
3435 
3436 iterator_range<rebase_iterator>
3437 MachOObjectFile::rebaseTable(Error &Err, MachOObjectFile *O,
3438                              ArrayRef<uint8_t> Opcodes, bool is64) {
3439   if (O->BindRebaseSectionTable == nullptr)
3440     O->BindRebaseSectionTable = std::make_unique<BindRebaseSegInfo>(O);
3441   MachORebaseEntry Start(&Err, O, Opcodes, is64);
3442   Start.moveToFirst();
3443 
3444   MachORebaseEntry Finish(&Err, O, Opcodes, is64);
3445   Finish.moveToEnd();
3446 
3447   return make_range(rebase_iterator(Start), rebase_iterator(Finish));
3448 }
3449 
3450 iterator_range<rebase_iterator> MachOObjectFile::rebaseTable(Error &Err) {
3451   return rebaseTable(Err, this, getDyldInfoRebaseOpcodes(), is64Bit());
3452 }
3453 
3454 MachOBindEntry::MachOBindEntry(Error *E, const MachOObjectFile *O,
3455                                ArrayRef<uint8_t> Bytes, bool is64Bit, Kind BK)
3456     : E(E), O(O), Opcodes(Bytes), Ptr(Bytes.begin()),
3457       PointerSize(is64Bit ? 8 : 4), TableKind(BK) {}
3458 
3459 void MachOBindEntry::moveToFirst() {
3460   Ptr = Opcodes.begin();
3461   moveNext();
3462 }
3463 
3464 void MachOBindEntry::moveToEnd() {
3465   Ptr = Opcodes.end();
3466   RemainingLoopCount = 0;
3467   Done = true;
3468 }
3469 
3470 void MachOBindEntry::moveNext() {
3471   ErrorAsOutParameter ErrAsOutParam(E);
3472   // If in the middle of some loop, move to next binding in loop.
3473   SegmentOffset += AdvanceAmount;
3474   if (RemainingLoopCount) {
3475     --RemainingLoopCount;
3476     return;
3477   }
3478   // BIND_OPCODE_DONE is only used for padding if we are not aligned to
3479   // pointer size. Therefore it is possible to reach the end without ever having
3480   // seen BIND_OPCODE_DONE.
3481   if (Ptr == Opcodes.end()) {
3482     Done = true;
3483     return;
3484   }
3485   bool More = true;
3486   while (More) {
3487     // Parse next opcode and set up next loop.
3488     const uint8_t *OpcodeStart = Ptr;
3489     uint8_t Byte = *Ptr++;
3490     uint8_t ImmValue = Byte & MachO::BIND_IMMEDIATE_MASK;
3491     uint8_t Opcode = Byte & MachO::BIND_OPCODE_MASK;
3492     int8_t SignExtended;
3493     const uint8_t *SymStart;
3494     uint32_t Count, Skip;
3495     const char *error = nullptr;
3496     switch (Opcode) {
3497     case MachO::BIND_OPCODE_DONE:
3498       if (TableKind == Kind::Lazy) {
3499         // Lazying bindings have a DONE opcode between entries.  Need to ignore
3500         // it to advance to next entry.  But need not if this is last entry.
3501         bool NotLastEntry = false;
3502         for (const uint8_t *P = Ptr; P < Opcodes.end(); ++P) {
3503           if (*P) {
3504             NotLastEntry = true;
3505           }
3506         }
3507         if (NotLastEntry)
3508           break;
3509       }
3510       More = false;
3511       moveToEnd();
3512       DEBUG_WITH_TYPE("mach-o-bind", dbgs() << "BIND_OPCODE_DONE\n");
3513       break;
3514     case MachO::BIND_OPCODE_SET_DYLIB_ORDINAL_IMM:
3515       if (TableKind == Kind::Weak) {
3516         *E = malformedError("BIND_OPCODE_SET_DYLIB_ORDINAL_IMM not allowed in "
3517                             "weak bind table for opcode at: 0x" +
3518                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3519         moveToEnd();
3520         return;
3521       }
3522       Ordinal = ImmValue;
3523       LibraryOrdinalSet = true;
3524       if (ImmValue > O->getLibraryCount()) {
3525         *E = malformedError("for BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB bad "
3526                             "library ordinal: " +
3527                             Twine((int)ImmValue) + " (max " +
3528                             Twine((int)O->getLibraryCount()) +
3529                             ") for opcode at: 0x" +
3530                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3531         moveToEnd();
3532         return;
3533       }
3534       DEBUG_WITH_TYPE(
3535           "mach-o-bind",
3536           dbgs() << "BIND_OPCODE_SET_DYLIB_ORDINAL_IMM: "
3537                  << "Ordinal=" << Ordinal << "\n");
3538       break;
3539     case MachO::BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB:
3540       if (TableKind == Kind::Weak) {
3541         *E = malformedError("BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB not allowed in "
3542                             "weak bind table for opcode at: 0x" +
3543                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3544         moveToEnd();
3545         return;
3546       }
3547       Ordinal = readULEB128(&error);
3548       LibraryOrdinalSet = true;
3549       if (error) {
3550         *E = malformedError("for BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB " +
3551                             Twine(error) + " for opcode at: 0x" +
3552                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3553         moveToEnd();
3554         return;
3555       }
3556       if (Ordinal > (int)O->getLibraryCount()) {
3557         *E = malformedError("for BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB bad "
3558                             "library ordinal: " +
3559                             Twine((int)Ordinal) + " (max " +
3560                             Twine((int)O->getLibraryCount()) +
3561                             ") for opcode at: 0x" +
3562                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3563         moveToEnd();
3564         return;
3565       }
3566       DEBUG_WITH_TYPE(
3567           "mach-o-bind",
3568           dbgs() << "BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB: "
3569                  << "Ordinal=" << Ordinal << "\n");
3570       break;
3571     case MachO::BIND_OPCODE_SET_DYLIB_SPECIAL_IMM:
3572       if (TableKind == Kind::Weak) {
3573         *E = malformedError("BIND_OPCODE_SET_DYLIB_SPECIAL_IMM not allowed in "
3574                             "weak bind table for opcode at: 0x" +
3575                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3576         moveToEnd();
3577         return;
3578       }
3579       if (ImmValue) {
3580         SignExtended = MachO::BIND_OPCODE_MASK | ImmValue;
3581         Ordinal = SignExtended;
3582         if (Ordinal < MachO::BIND_SPECIAL_DYLIB_FLAT_LOOKUP) {
3583           *E = malformedError("for BIND_OPCODE_SET_DYLIB_SPECIAL_IMM unknown "
3584                               "special ordinal: " +
3585                               Twine((int)Ordinal) + " for opcode at: 0x" +
3586                               Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3587           moveToEnd();
3588           return;
3589         }
3590       } else
3591         Ordinal = 0;
3592       LibraryOrdinalSet = true;
3593       DEBUG_WITH_TYPE(
3594           "mach-o-bind",
3595           dbgs() << "BIND_OPCODE_SET_DYLIB_SPECIAL_IMM: "
3596                  << "Ordinal=" << Ordinal << "\n");
3597       break;
3598     case MachO::BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM:
3599       Flags = ImmValue;
3600       SymStart = Ptr;
3601       while (*Ptr && (Ptr < Opcodes.end())) {
3602         ++Ptr;
3603       }
3604       if (Ptr == Opcodes.end()) {
3605         *E = malformedError(
3606             "for BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM "
3607             "symbol name extends past opcodes for opcode at: 0x" +
3608             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3609         moveToEnd();
3610         return;
3611       }
3612       SymbolName = StringRef(reinterpret_cast<const char*>(SymStart),
3613                              Ptr-SymStart);
3614       ++Ptr;
3615       DEBUG_WITH_TYPE(
3616           "mach-o-bind",
3617           dbgs() << "BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM: "
3618                  << "SymbolName=" << SymbolName << "\n");
3619       if (TableKind == Kind::Weak) {
3620         if (ImmValue & MachO::BIND_SYMBOL_FLAGS_NON_WEAK_DEFINITION)
3621           return;
3622       }
3623       break;
3624     case MachO::BIND_OPCODE_SET_TYPE_IMM:
3625       BindType = ImmValue;
3626       if (ImmValue > MachO::BIND_TYPE_TEXT_PCREL32) {
3627         *E = malformedError("for BIND_OPCODE_SET_TYPE_IMM bad bind type: " +
3628                             Twine((int)ImmValue) + " for opcode at: 0x" +
3629                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3630         moveToEnd();
3631         return;
3632       }
3633       DEBUG_WITH_TYPE(
3634           "mach-o-bind",
3635           dbgs() << "BIND_OPCODE_SET_TYPE_IMM: "
3636                  << "BindType=" << (int)BindType << "\n");
3637       break;
3638     case MachO::BIND_OPCODE_SET_ADDEND_SLEB:
3639       Addend = readSLEB128(&error);
3640       if (error) {
3641         *E = malformedError("for BIND_OPCODE_SET_ADDEND_SLEB " + Twine(error) +
3642                             " for opcode at: 0x" +
3643                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3644         moveToEnd();
3645         return;
3646       }
3647       DEBUG_WITH_TYPE(
3648           "mach-o-bind",
3649           dbgs() << "BIND_OPCODE_SET_ADDEND_SLEB: "
3650                  << "Addend=" << Addend << "\n");
3651       break;
3652     case MachO::BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
3653       SegmentIndex = ImmValue;
3654       SegmentOffset = readULEB128(&error);
3655       if (error) {
3656         *E = malformedError("for BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB " +
3657                             Twine(error) + " for opcode at: 0x" +
3658                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3659         moveToEnd();
3660         return;
3661       }
3662       error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3663                                              PointerSize);
3664       if (error) {
3665         *E = malformedError("for BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB " +
3666                             Twine(error) + " for opcode at: 0x" +
3667                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3668         moveToEnd();
3669         return;
3670       }
3671       DEBUG_WITH_TYPE(
3672           "mach-o-bind",
3673           dbgs() << "BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB: "
3674                  << "SegmentIndex=" << SegmentIndex << ", "
3675                  << format("SegmentOffset=0x%06X", SegmentOffset)
3676                  << "\n");
3677       break;
3678     case MachO::BIND_OPCODE_ADD_ADDR_ULEB:
3679       SegmentOffset += readULEB128(&error);
3680       if (error) {
3681         *E = malformedError("for BIND_OPCODE_ADD_ADDR_ULEB " + Twine(error) +
3682                             " for opcode at: 0x" +
3683                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3684         moveToEnd();
3685         return;
3686       }
3687       error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3688                                              PointerSize);
3689       if (error) {
3690         *E = malformedError("for BIND_OPCODE_ADD_ADDR_ULEB " + Twine(error) +
3691                             " for opcode at: 0x" +
3692                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3693         moveToEnd();
3694         return;
3695       }
3696       DEBUG_WITH_TYPE("mach-o-bind",
3697                       dbgs() << "BIND_OPCODE_ADD_ADDR_ULEB: "
3698                              << format("SegmentOffset=0x%06X",
3699                                        SegmentOffset) << "\n");
3700       break;
3701     case MachO::BIND_OPCODE_DO_BIND:
3702       AdvanceAmount = PointerSize;
3703       RemainingLoopCount = 0;
3704       error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3705                                              PointerSize);
3706       if (error) {
3707         *E = malformedError("for BIND_OPCODE_DO_BIND " + Twine(error) +
3708                             " for opcode at: 0x" +
3709                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3710         moveToEnd();
3711         return;
3712       }
3713       if (SymbolName == StringRef()) {
3714         *E = malformedError(
3715             "for BIND_OPCODE_DO_BIND missing preceding "
3716             "BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM for opcode at: 0x" +
3717             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3718         moveToEnd();
3719         return;
3720       }
3721       if (!LibraryOrdinalSet && TableKind != Kind::Weak) {
3722         *E =
3723             malformedError("for BIND_OPCODE_DO_BIND missing preceding "
3724                            "BIND_OPCODE_SET_DYLIB_ORDINAL_* for opcode at: 0x" +
3725                            Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3726         moveToEnd();
3727         return;
3728       }
3729       DEBUG_WITH_TYPE("mach-o-bind",
3730                       dbgs() << "BIND_OPCODE_DO_BIND: "
3731                              << format("SegmentOffset=0x%06X",
3732                                        SegmentOffset) << "\n");
3733       return;
3734      case MachO::BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB:
3735       if (TableKind == Kind::Lazy) {
3736         *E = malformedError("BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB not allowed in "
3737                             "lazy bind table for opcode at: 0x" +
3738                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3739         moveToEnd();
3740         return;
3741       }
3742       error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3743                                              PointerSize);
3744       if (error) {
3745         *E = malformedError("for BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB " +
3746                             Twine(error) + " for opcode at: 0x" +
3747                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3748         moveToEnd();
3749         return;
3750       }
3751       if (SymbolName == StringRef()) {
3752         *E = malformedError(
3753             "for BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB missing "
3754             "preceding BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM for opcode "
3755             "at: 0x" +
3756             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3757         moveToEnd();
3758         return;
3759       }
3760       if (!LibraryOrdinalSet && TableKind != Kind::Weak) {
3761         *E = malformedError(
3762             "for BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB missing "
3763             "preceding BIND_OPCODE_SET_DYLIB_ORDINAL_* for opcode at: 0x" +
3764             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3765         moveToEnd();
3766         return;
3767       }
3768       AdvanceAmount = readULEB128(&error) + PointerSize;
3769       if (error) {
3770         *E = malformedError("for BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB " +
3771                             Twine(error) + " for opcode at: 0x" +
3772                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3773         moveToEnd();
3774         return;
3775       }
3776       // Note, this is not really an error until the next bind but make no sense
3777       // for a BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB to not be followed by another
3778       // bind operation.
3779       error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset +
3780                                             AdvanceAmount, PointerSize);
3781       if (error) {
3782         *E = malformedError("for BIND_OPCODE_ADD_ADDR_ULEB (after adding "
3783                             "ULEB) " +
3784                             Twine(error) + " for opcode at: 0x" +
3785                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3786         moveToEnd();
3787         return;
3788       }
3789       RemainingLoopCount = 0;
3790       DEBUG_WITH_TYPE(
3791           "mach-o-bind",
3792           dbgs() << "BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB: "
3793                  << format("SegmentOffset=0x%06X", SegmentOffset)
3794                  << ", AdvanceAmount=" << AdvanceAmount
3795                  << ", RemainingLoopCount=" << RemainingLoopCount
3796                  << "\n");
3797       return;
3798     case MachO::BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED:
3799       if (TableKind == Kind::Lazy) {
3800         *E = malformedError("BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED not "
3801                             "allowed in lazy bind table for opcode at: 0x" +
3802                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3803         moveToEnd();
3804         return;
3805       }
3806       error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3807                                              PointerSize);
3808       if (error) {
3809         *E = malformedError("for BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED " +
3810                             Twine(error) + " for opcode at: 0x" +
3811                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3812         moveToEnd();
3813         return;
3814       }
3815       if (SymbolName == StringRef()) {
3816         *E = malformedError(
3817             "for BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED "
3818             "missing preceding BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM for "
3819             "opcode at: 0x" +
3820             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3821         moveToEnd();
3822         return;
3823       }
3824       if (!LibraryOrdinalSet && TableKind != Kind::Weak) {
3825         *E = malformedError(
3826             "for BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED "
3827             "missing preceding BIND_OPCODE_SET_DYLIB_ORDINAL_* for opcode "
3828             "at: 0x" +
3829             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3830         moveToEnd();
3831         return;
3832       }
3833       AdvanceAmount = ImmValue * PointerSize + PointerSize;
3834       RemainingLoopCount = 0;
3835       error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset +
3836                                              AdvanceAmount, PointerSize);
3837       if (error) {
3838         *E =
3839             malformedError("for BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED "
3840                            " (after adding immediate times the pointer size) " +
3841                            Twine(error) + " for opcode at: 0x" +
3842                            Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3843         moveToEnd();
3844         return;
3845       }
3846       DEBUG_WITH_TYPE("mach-o-bind",
3847                       dbgs()
3848                       << "BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED: "
3849                       << format("SegmentOffset=0x%06X", SegmentOffset) << "\n");
3850       return;
3851     case MachO::BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB:
3852       if (TableKind == Kind::Lazy) {
3853         *E = malformedError("BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB not "
3854                             "allowed in lazy bind table for opcode at: 0x" +
3855                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3856         moveToEnd();
3857         return;
3858       }
3859       Count = readULEB128(&error);
3860       if (Count != 0)
3861         RemainingLoopCount = Count - 1;
3862       else
3863         RemainingLoopCount = 0;
3864       if (error) {
3865         *E = malformedError("for BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB "
3866                             " (count value) " +
3867                             Twine(error) + " for opcode at: 0x" +
3868                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3869         moveToEnd();
3870         return;
3871       }
3872       Skip = readULEB128(&error);
3873       AdvanceAmount = Skip + PointerSize;
3874       if (error) {
3875         *E = malformedError("for BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB "
3876                             " (skip value) " +
3877                             Twine(error) + " for opcode at: 0x" +
3878                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3879         moveToEnd();
3880         return;
3881       }
3882       if (SymbolName == StringRef()) {
3883         *E = malformedError(
3884             "for BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB "
3885             "missing preceding BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM for "
3886             "opcode at: 0x" +
3887             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3888         moveToEnd();
3889         return;
3890       }
3891       if (!LibraryOrdinalSet && TableKind != Kind::Weak) {
3892         *E = malformedError(
3893             "for BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB "
3894             "missing preceding BIND_OPCODE_SET_DYLIB_ORDINAL_* for opcode "
3895             "at: 0x" +
3896             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3897         moveToEnd();
3898         return;
3899       }
3900       error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3901                                              PointerSize, Count, Skip);
3902       if (error) {
3903         *E =
3904             malformedError("for BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB " +
3905                            Twine(error) + " for opcode at: 0x" +
3906                            Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3907         moveToEnd();
3908         return;
3909       }
3910       DEBUG_WITH_TYPE(
3911           "mach-o-bind",
3912           dbgs() << "BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB: "
3913                  << format("SegmentOffset=0x%06X", SegmentOffset)
3914                  << ", AdvanceAmount=" << AdvanceAmount
3915                  << ", RemainingLoopCount=" << RemainingLoopCount
3916                  << "\n");
3917       return;
3918     default:
3919       *E = malformedError("bad bind info (bad opcode value 0x" +
3920                           Twine::utohexstr(Opcode) + " for opcode at: 0x" +
3921                           Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3922       moveToEnd();
3923       return;
3924     }
3925   }
3926 }
3927 
3928 uint64_t MachOBindEntry::readULEB128(const char **error) {
3929   unsigned Count;
3930   uint64_t Result = decodeULEB128(Ptr, &Count, Opcodes.end(), error);
3931   Ptr += Count;
3932   if (Ptr > Opcodes.end())
3933     Ptr = Opcodes.end();
3934   return Result;
3935 }
3936 
3937 int64_t MachOBindEntry::readSLEB128(const char **error) {
3938   unsigned Count;
3939   int64_t Result = decodeSLEB128(Ptr, &Count, Opcodes.end(), error);
3940   Ptr += Count;
3941   if (Ptr > Opcodes.end())
3942     Ptr = Opcodes.end();
3943   return Result;
3944 }
3945 
3946 int32_t MachOBindEntry::segmentIndex() const { return SegmentIndex; }
3947 
3948 uint64_t MachOBindEntry::segmentOffset() const { return SegmentOffset; }
3949 
3950 StringRef MachOBindEntry::typeName() const {
3951   switch (BindType) {
3952   case MachO::BIND_TYPE_POINTER:
3953     return "pointer";
3954   case MachO::BIND_TYPE_TEXT_ABSOLUTE32:
3955     return "text abs32";
3956   case MachO::BIND_TYPE_TEXT_PCREL32:
3957     return "text rel32";
3958   }
3959   return "unknown";
3960 }
3961 
3962 StringRef MachOBindEntry::symbolName() const { return SymbolName; }
3963 
3964 int64_t MachOBindEntry::addend() const { return Addend; }
3965 
3966 uint32_t MachOBindEntry::flags() const { return Flags; }
3967 
3968 int MachOBindEntry::ordinal() const { return Ordinal; }
3969 
3970 // For use with the SegIndex of a checked Mach-O Bind entry
3971 // to get the segment name.
3972 StringRef MachOBindEntry::segmentName() const {
3973   return O->BindRebaseSegmentName(SegmentIndex);
3974 }
3975 
3976 // For use with a SegIndex,SegOffset pair from a checked Mach-O Bind entry
3977 // to get the section name.
3978 StringRef MachOBindEntry::sectionName() const {
3979   return O->BindRebaseSectionName(SegmentIndex, SegmentOffset);
3980 }
3981 
3982 // For use with a SegIndex,SegOffset pair from a checked Mach-O Bind entry
3983 // to get the address.
3984 uint64_t MachOBindEntry::address() const {
3985   return O->BindRebaseAddress(SegmentIndex, SegmentOffset);
3986 }
3987 
3988 bool MachOBindEntry::operator==(const MachOBindEntry &Other) const {
3989 #ifdef EXPENSIVE_CHECKS
3990   assert(Opcodes == Other.Opcodes && "compare iterators of different files");
3991 #else
3992   assert(Opcodes.data() == Other.Opcodes.data() && "compare iterators of different files");
3993 #endif
3994   return (Ptr == Other.Ptr) &&
3995          (RemainingLoopCount == Other.RemainingLoopCount) &&
3996          (Done == Other.Done);
3997 }
3998 
3999 // Build table of sections so SegIndex/SegOffset pairs can be translated.
4000 BindRebaseSegInfo::BindRebaseSegInfo(const object::MachOObjectFile *Obj) {
4001   uint32_t CurSegIndex = Obj->hasPageZeroSegment() ? 1 : 0;
4002   StringRef CurSegName;
4003   uint64_t CurSegAddress;
4004   for (const SectionRef &Section : Obj->sections()) {
4005     SectionInfo Info;
4006     Expected<StringRef> NameOrErr = Section.getName();
4007     if (!NameOrErr)
4008       consumeError(NameOrErr.takeError());
4009     else
4010       Info.SectionName = *NameOrErr;
4011     Info.Address = Section.getAddress();
4012     Info.Size = Section.getSize();
4013     Info.SegmentName =
4014         Obj->getSectionFinalSegmentName(Section.getRawDataRefImpl());
4015     if (!Info.SegmentName.equals(CurSegName)) {
4016       ++CurSegIndex;
4017       CurSegName = Info.SegmentName;
4018       CurSegAddress = Info.Address;
4019     }
4020     Info.SegmentIndex = CurSegIndex - 1;
4021     Info.OffsetInSegment = Info.Address - CurSegAddress;
4022     Info.SegmentStartAddress = CurSegAddress;
4023     Sections.push_back(Info);
4024   }
4025   MaxSegIndex = CurSegIndex;
4026 }
4027 
4028 // For use with a SegIndex, SegOffset, and PointerSize triple in
4029 // MachOBindEntry::moveNext() to validate a MachOBindEntry or MachORebaseEntry.
4030 //
4031 // Given a SegIndex, SegOffset, and PointerSize, verify a valid section exists
4032 // that fully contains a pointer at that location. Multiple fixups in a bind
4033 // (such as with the BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB opcode) can
4034 // be tested via the Count and Skip parameters.
4035 const char * BindRebaseSegInfo::checkSegAndOffsets(int32_t SegIndex,
4036                                                    uint64_t SegOffset,
4037                                                    uint8_t PointerSize,
4038                                                    uint32_t Count,
4039                                                    uint32_t Skip) {
4040   if (SegIndex == -1)
4041     return "missing preceding *_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB";
4042   if (SegIndex >= MaxSegIndex)
4043     return "bad segIndex (too large)";
4044   for (uint32_t i = 0; i < Count; ++i) {
4045     uint32_t Start = SegOffset + i * (PointerSize + Skip);
4046     uint32_t End = Start + PointerSize;
4047     bool Found = false;
4048     for (const SectionInfo &SI : Sections) {
4049       if (SI.SegmentIndex != SegIndex)
4050         continue;
4051       if ((SI.OffsetInSegment<=Start) && (Start<(SI.OffsetInSegment+SI.Size))) {
4052         if (End <= SI.OffsetInSegment + SI.Size) {
4053           Found = true;
4054           break;
4055         }
4056         else
4057           return "bad offset, extends beyond section boundary";
4058       }
4059     }
4060     if (!Found)
4061       return "bad offset, not in section";
4062   }
4063   return nullptr;
4064 }
4065 
4066 // For use with the SegIndex of a checked Mach-O Bind or Rebase entry
4067 // to get the segment name.
4068 StringRef BindRebaseSegInfo::segmentName(int32_t SegIndex) {
4069   for (const SectionInfo &SI : Sections) {
4070     if (SI.SegmentIndex == SegIndex)
4071       return SI.SegmentName;
4072   }
4073   llvm_unreachable("invalid SegIndex");
4074 }
4075 
4076 // For use with a SegIndex,SegOffset pair from a checked Mach-O Bind or Rebase
4077 // to get the SectionInfo.
4078 const BindRebaseSegInfo::SectionInfo &BindRebaseSegInfo::findSection(
4079                                      int32_t SegIndex, uint64_t SegOffset) {
4080   for (const SectionInfo &SI : Sections) {
4081     if (SI.SegmentIndex != SegIndex)
4082       continue;
4083     if (SI.OffsetInSegment > SegOffset)
4084       continue;
4085     if (SegOffset >= (SI.OffsetInSegment + SI.Size))
4086       continue;
4087     return SI;
4088   }
4089   llvm_unreachable("SegIndex and SegOffset not in any section");
4090 }
4091 
4092 // For use with a SegIndex,SegOffset pair from a checked Mach-O Bind or Rebase
4093 // entry to get the section name.
4094 StringRef BindRebaseSegInfo::sectionName(int32_t SegIndex,
4095                                          uint64_t SegOffset) {
4096   return findSection(SegIndex, SegOffset).SectionName;
4097 }
4098 
4099 // For use with a SegIndex,SegOffset pair from a checked Mach-O Bind or Rebase
4100 // entry to get the address.
4101 uint64_t BindRebaseSegInfo::address(uint32_t SegIndex, uint64_t OffsetInSeg) {
4102   const SectionInfo &SI = findSection(SegIndex, OffsetInSeg);
4103   return SI.SegmentStartAddress + OffsetInSeg;
4104 }
4105 
4106 iterator_range<bind_iterator>
4107 MachOObjectFile::bindTable(Error &Err, MachOObjectFile *O,
4108                            ArrayRef<uint8_t> Opcodes, bool is64,
4109                            MachOBindEntry::Kind BKind) {
4110   if (O->BindRebaseSectionTable == nullptr)
4111     O->BindRebaseSectionTable = std::make_unique<BindRebaseSegInfo>(O);
4112   MachOBindEntry Start(&Err, O, Opcodes, is64, BKind);
4113   Start.moveToFirst();
4114 
4115   MachOBindEntry Finish(&Err, O, Opcodes, is64, BKind);
4116   Finish.moveToEnd();
4117 
4118   return make_range(bind_iterator(Start), bind_iterator(Finish));
4119 }
4120 
4121 iterator_range<bind_iterator> MachOObjectFile::bindTable(Error &Err) {
4122   return bindTable(Err, this, getDyldInfoBindOpcodes(), is64Bit(),
4123                    MachOBindEntry::Kind::Regular);
4124 }
4125 
4126 iterator_range<bind_iterator> MachOObjectFile::lazyBindTable(Error &Err) {
4127   return bindTable(Err, this, getDyldInfoLazyBindOpcodes(), is64Bit(),
4128                    MachOBindEntry::Kind::Lazy);
4129 }
4130 
4131 iterator_range<bind_iterator> MachOObjectFile::weakBindTable(Error &Err) {
4132   return bindTable(Err, this, getDyldInfoWeakBindOpcodes(), is64Bit(),
4133                    MachOBindEntry::Kind::Weak);
4134 }
4135 
4136 MachOObjectFile::load_command_iterator
4137 MachOObjectFile::begin_load_commands() const {
4138   return LoadCommands.begin();
4139 }
4140 
4141 MachOObjectFile::load_command_iterator
4142 MachOObjectFile::end_load_commands() const {
4143   return LoadCommands.end();
4144 }
4145 
4146 iterator_range<MachOObjectFile::load_command_iterator>
4147 MachOObjectFile::load_commands() const {
4148   return make_range(begin_load_commands(), end_load_commands());
4149 }
4150 
4151 StringRef
4152 MachOObjectFile::getSectionFinalSegmentName(DataRefImpl Sec) const {
4153   ArrayRef<char> Raw = getSectionRawFinalSegmentName(Sec);
4154   return parseSegmentOrSectionName(Raw.data());
4155 }
4156 
4157 ArrayRef<char>
4158 MachOObjectFile::getSectionRawName(DataRefImpl Sec) const {
4159   assert(Sec.d.a < Sections.size() && "Should have detected this earlier");
4160   const section_base *Base =
4161     reinterpret_cast<const section_base *>(Sections[Sec.d.a]);
4162   return makeArrayRef(Base->sectname);
4163 }
4164 
4165 ArrayRef<char>
4166 MachOObjectFile::getSectionRawFinalSegmentName(DataRefImpl Sec) const {
4167   assert(Sec.d.a < Sections.size() && "Should have detected this earlier");
4168   const section_base *Base =
4169     reinterpret_cast<const section_base *>(Sections[Sec.d.a]);
4170   return makeArrayRef(Base->segname);
4171 }
4172 
4173 bool
4174 MachOObjectFile::isRelocationScattered(const MachO::any_relocation_info &RE)
4175   const {
4176   if (getCPUType(*this) == MachO::CPU_TYPE_X86_64)
4177     return false;
4178   return getPlainRelocationAddress(RE) & MachO::R_SCATTERED;
4179 }
4180 
4181 unsigned MachOObjectFile::getPlainRelocationSymbolNum(
4182     const MachO::any_relocation_info &RE) const {
4183   if (isLittleEndian())
4184     return RE.r_word1 & 0xffffff;
4185   return RE.r_word1 >> 8;
4186 }
4187 
4188 bool MachOObjectFile::getPlainRelocationExternal(
4189     const MachO::any_relocation_info &RE) const {
4190   if (isLittleEndian())
4191     return (RE.r_word1 >> 27) & 1;
4192   return (RE.r_word1 >> 4) & 1;
4193 }
4194 
4195 bool MachOObjectFile::getScatteredRelocationScattered(
4196     const MachO::any_relocation_info &RE) const {
4197   return RE.r_word0 >> 31;
4198 }
4199 
4200 uint32_t MachOObjectFile::getScatteredRelocationValue(
4201     const MachO::any_relocation_info &RE) const {
4202   return RE.r_word1;
4203 }
4204 
4205 uint32_t MachOObjectFile::getScatteredRelocationType(
4206     const MachO::any_relocation_info &RE) const {
4207   return (RE.r_word0 >> 24) & 0xf;
4208 }
4209 
4210 unsigned MachOObjectFile::getAnyRelocationAddress(
4211     const MachO::any_relocation_info &RE) const {
4212   if (isRelocationScattered(RE))
4213     return getScatteredRelocationAddress(RE);
4214   return getPlainRelocationAddress(RE);
4215 }
4216 
4217 unsigned MachOObjectFile::getAnyRelocationPCRel(
4218     const MachO::any_relocation_info &RE) const {
4219   if (isRelocationScattered(RE))
4220     return getScatteredRelocationPCRel(RE);
4221   return getPlainRelocationPCRel(*this, RE);
4222 }
4223 
4224 unsigned MachOObjectFile::getAnyRelocationLength(
4225     const MachO::any_relocation_info &RE) const {
4226   if (isRelocationScattered(RE))
4227     return getScatteredRelocationLength(RE);
4228   return getPlainRelocationLength(*this, RE);
4229 }
4230 
4231 unsigned
4232 MachOObjectFile::getAnyRelocationType(
4233                                    const MachO::any_relocation_info &RE) const {
4234   if (isRelocationScattered(RE))
4235     return getScatteredRelocationType(RE);
4236   return getPlainRelocationType(*this, RE);
4237 }
4238 
4239 SectionRef
4240 MachOObjectFile::getAnyRelocationSection(
4241                                    const MachO::any_relocation_info &RE) const {
4242   if (isRelocationScattered(RE) || getPlainRelocationExternal(RE))
4243     return *section_end();
4244   unsigned SecNum = getPlainRelocationSymbolNum(RE);
4245   if (SecNum == MachO::R_ABS || SecNum > Sections.size())
4246     return *section_end();
4247   DataRefImpl DRI;
4248   DRI.d.a = SecNum - 1;
4249   return SectionRef(DRI, this);
4250 }
4251 
4252 MachO::section MachOObjectFile::getSection(DataRefImpl DRI) const {
4253   assert(DRI.d.a < Sections.size() && "Should have detected this earlier");
4254   return getStruct<MachO::section>(*this, Sections[DRI.d.a]);
4255 }
4256 
4257 MachO::section_64 MachOObjectFile::getSection64(DataRefImpl DRI) const {
4258   assert(DRI.d.a < Sections.size() && "Should have detected this earlier");
4259   return getStruct<MachO::section_64>(*this, Sections[DRI.d.a]);
4260 }
4261 
4262 MachO::section MachOObjectFile::getSection(const LoadCommandInfo &L,
4263                                            unsigned Index) const {
4264   const char *Sec = getSectionPtr(*this, L, Index);
4265   return getStruct<MachO::section>(*this, Sec);
4266 }
4267 
4268 MachO::section_64 MachOObjectFile::getSection64(const LoadCommandInfo &L,
4269                                                 unsigned Index) const {
4270   const char *Sec = getSectionPtr(*this, L, Index);
4271   return getStruct<MachO::section_64>(*this, Sec);
4272 }
4273 
4274 MachO::nlist
4275 MachOObjectFile::getSymbolTableEntry(DataRefImpl DRI) const {
4276   const char *P = reinterpret_cast<const char *>(DRI.p);
4277   return getStruct<MachO::nlist>(*this, P);
4278 }
4279 
4280 MachO::nlist_64
4281 MachOObjectFile::getSymbol64TableEntry(DataRefImpl DRI) const {
4282   const char *P = reinterpret_cast<const char *>(DRI.p);
4283   return getStruct<MachO::nlist_64>(*this, P);
4284 }
4285 
4286 MachO::linkedit_data_command
4287 MachOObjectFile::getLinkeditDataLoadCommand(const LoadCommandInfo &L) const {
4288   return getStruct<MachO::linkedit_data_command>(*this, L.Ptr);
4289 }
4290 
4291 MachO::segment_command
4292 MachOObjectFile::getSegmentLoadCommand(const LoadCommandInfo &L) const {
4293   return getStruct<MachO::segment_command>(*this, L.Ptr);
4294 }
4295 
4296 MachO::segment_command_64
4297 MachOObjectFile::getSegment64LoadCommand(const LoadCommandInfo &L) const {
4298   return getStruct<MachO::segment_command_64>(*this, L.Ptr);
4299 }
4300 
4301 MachO::linker_option_command
4302 MachOObjectFile::getLinkerOptionLoadCommand(const LoadCommandInfo &L) const {
4303   return getStruct<MachO::linker_option_command>(*this, L.Ptr);
4304 }
4305 
4306 MachO::version_min_command
4307 MachOObjectFile::getVersionMinLoadCommand(const LoadCommandInfo &L) const {
4308   return getStruct<MachO::version_min_command>(*this, L.Ptr);
4309 }
4310 
4311 MachO::note_command
4312 MachOObjectFile::getNoteLoadCommand(const LoadCommandInfo &L) const {
4313   return getStruct<MachO::note_command>(*this, L.Ptr);
4314 }
4315 
4316 MachO::build_version_command
4317 MachOObjectFile::getBuildVersionLoadCommand(const LoadCommandInfo &L) const {
4318   return getStruct<MachO::build_version_command>(*this, L.Ptr);
4319 }
4320 
4321 MachO::build_tool_version
4322 MachOObjectFile::getBuildToolVersion(unsigned index) const {
4323   return getStruct<MachO::build_tool_version>(*this, BuildTools[index]);
4324 }
4325 
4326 MachO::dylib_command
4327 MachOObjectFile::getDylibIDLoadCommand(const LoadCommandInfo &L) const {
4328   return getStruct<MachO::dylib_command>(*this, L.Ptr);
4329 }
4330 
4331 MachO::dyld_info_command
4332 MachOObjectFile::getDyldInfoLoadCommand(const LoadCommandInfo &L) const {
4333   return getStruct<MachO::dyld_info_command>(*this, L.Ptr);
4334 }
4335 
4336 MachO::dylinker_command
4337 MachOObjectFile::getDylinkerCommand(const LoadCommandInfo &L) const {
4338   return getStruct<MachO::dylinker_command>(*this, L.Ptr);
4339 }
4340 
4341 MachO::uuid_command
4342 MachOObjectFile::getUuidCommand(const LoadCommandInfo &L) const {
4343   return getStruct<MachO::uuid_command>(*this, L.Ptr);
4344 }
4345 
4346 MachO::rpath_command
4347 MachOObjectFile::getRpathCommand(const LoadCommandInfo &L) const {
4348   return getStruct<MachO::rpath_command>(*this, L.Ptr);
4349 }
4350 
4351 MachO::source_version_command
4352 MachOObjectFile::getSourceVersionCommand(const LoadCommandInfo &L) const {
4353   return getStruct<MachO::source_version_command>(*this, L.Ptr);
4354 }
4355 
4356 MachO::entry_point_command
4357 MachOObjectFile::getEntryPointCommand(const LoadCommandInfo &L) const {
4358   return getStruct<MachO::entry_point_command>(*this, L.Ptr);
4359 }
4360 
4361 MachO::encryption_info_command
4362 MachOObjectFile::getEncryptionInfoCommand(const LoadCommandInfo &L) const {
4363   return getStruct<MachO::encryption_info_command>(*this, L.Ptr);
4364 }
4365 
4366 MachO::encryption_info_command_64
4367 MachOObjectFile::getEncryptionInfoCommand64(const LoadCommandInfo &L) const {
4368   return getStruct<MachO::encryption_info_command_64>(*this, L.Ptr);
4369 }
4370 
4371 MachO::sub_framework_command
4372 MachOObjectFile::getSubFrameworkCommand(const LoadCommandInfo &L) const {
4373   return getStruct<MachO::sub_framework_command>(*this, L.Ptr);
4374 }
4375 
4376 MachO::sub_umbrella_command
4377 MachOObjectFile::getSubUmbrellaCommand(const LoadCommandInfo &L) const {
4378   return getStruct<MachO::sub_umbrella_command>(*this, L.Ptr);
4379 }
4380 
4381 MachO::sub_library_command
4382 MachOObjectFile::getSubLibraryCommand(const LoadCommandInfo &L) const {
4383   return getStruct<MachO::sub_library_command>(*this, L.Ptr);
4384 }
4385 
4386 MachO::sub_client_command
4387 MachOObjectFile::getSubClientCommand(const LoadCommandInfo &L) const {
4388   return getStruct<MachO::sub_client_command>(*this, L.Ptr);
4389 }
4390 
4391 MachO::routines_command
4392 MachOObjectFile::getRoutinesCommand(const LoadCommandInfo &L) const {
4393   return getStruct<MachO::routines_command>(*this, L.Ptr);
4394 }
4395 
4396 MachO::routines_command_64
4397 MachOObjectFile::getRoutinesCommand64(const LoadCommandInfo &L) const {
4398   return getStruct<MachO::routines_command_64>(*this, L.Ptr);
4399 }
4400 
4401 MachO::thread_command
4402 MachOObjectFile::getThreadCommand(const LoadCommandInfo &L) const {
4403   return getStruct<MachO::thread_command>(*this, L.Ptr);
4404 }
4405 
4406 MachO::any_relocation_info
4407 MachOObjectFile::getRelocation(DataRefImpl Rel) const {
4408   uint32_t Offset;
4409   if (getHeader().filetype == MachO::MH_OBJECT) {
4410     DataRefImpl Sec;
4411     Sec.d.a = Rel.d.a;
4412     if (is64Bit()) {
4413       MachO::section_64 Sect = getSection64(Sec);
4414       Offset = Sect.reloff;
4415     } else {
4416       MachO::section Sect = getSection(Sec);
4417       Offset = Sect.reloff;
4418     }
4419   } else {
4420     MachO::dysymtab_command DysymtabLoadCmd = getDysymtabLoadCommand();
4421     if (Rel.d.a == 0)
4422       Offset = DysymtabLoadCmd.extreloff; // Offset to the external relocations
4423     else
4424       Offset = DysymtabLoadCmd.locreloff; // Offset to the local relocations
4425   }
4426 
4427   auto P = reinterpret_cast<const MachO::any_relocation_info *>(
4428       getPtr(*this, Offset)) + Rel.d.b;
4429   return getStruct<MachO::any_relocation_info>(
4430       *this, reinterpret_cast<const char *>(P));
4431 }
4432 
4433 MachO::data_in_code_entry
4434 MachOObjectFile::getDice(DataRefImpl Rel) const {
4435   const char *P = reinterpret_cast<const char *>(Rel.p);
4436   return getStruct<MachO::data_in_code_entry>(*this, P);
4437 }
4438 
4439 const MachO::mach_header &MachOObjectFile::getHeader() const {
4440   return Header;
4441 }
4442 
4443 const MachO::mach_header_64 &MachOObjectFile::getHeader64() const {
4444   assert(is64Bit());
4445   return Header64;
4446 }
4447 
4448 uint32_t MachOObjectFile::getIndirectSymbolTableEntry(
4449                                              const MachO::dysymtab_command &DLC,
4450                                              unsigned Index) const {
4451   uint64_t Offset = DLC.indirectsymoff + Index * sizeof(uint32_t);
4452   return getStruct<uint32_t>(*this, getPtr(*this, Offset));
4453 }
4454 
4455 MachO::data_in_code_entry
4456 MachOObjectFile::getDataInCodeTableEntry(uint32_t DataOffset,
4457                                          unsigned Index) const {
4458   uint64_t Offset = DataOffset + Index * sizeof(MachO::data_in_code_entry);
4459   return getStruct<MachO::data_in_code_entry>(*this, getPtr(*this, Offset));
4460 }
4461 
4462 MachO::symtab_command MachOObjectFile::getSymtabLoadCommand() const {
4463   if (SymtabLoadCmd)
4464     return getStruct<MachO::symtab_command>(*this, SymtabLoadCmd);
4465 
4466   // If there is no SymtabLoadCmd return a load command with zero'ed fields.
4467   MachO::symtab_command Cmd;
4468   Cmd.cmd = MachO::LC_SYMTAB;
4469   Cmd.cmdsize = sizeof(MachO::symtab_command);
4470   Cmd.symoff = 0;
4471   Cmd.nsyms = 0;
4472   Cmd.stroff = 0;
4473   Cmd.strsize = 0;
4474   return Cmd;
4475 }
4476 
4477 MachO::dysymtab_command MachOObjectFile::getDysymtabLoadCommand() const {
4478   if (DysymtabLoadCmd)
4479     return getStruct<MachO::dysymtab_command>(*this, DysymtabLoadCmd);
4480 
4481   // If there is no DysymtabLoadCmd return a load command with zero'ed fields.
4482   MachO::dysymtab_command Cmd;
4483   Cmd.cmd = MachO::LC_DYSYMTAB;
4484   Cmd.cmdsize = sizeof(MachO::dysymtab_command);
4485   Cmd.ilocalsym = 0;
4486   Cmd.nlocalsym = 0;
4487   Cmd.iextdefsym = 0;
4488   Cmd.nextdefsym = 0;
4489   Cmd.iundefsym = 0;
4490   Cmd.nundefsym = 0;
4491   Cmd.tocoff = 0;
4492   Cmd.ntoc = 0;
4493   Cmd.modtaboff = 0;
4494   Cmd.nmodtab = 0;
4495   Cmd.extrefsymoff = 0;
4496   Cmd.nextrefsyms = 0;
4497   Cmd.indirectsymoff = 0;
4498   Cmd.nindirectsyms = 0;
4499   Cmd.extreloff = 0;
4500   Cmd.nextrel = 0;
4501   Cmd.locreloff = 0;
4502   Cmd.nlocrel = 0;
4503   return Cmd;
4504 }
4505 
4506 MachO::linkedit_data_command
4507 MachOObjectFile::getDataInCodeLoadCommand() const {
4508   if (DataInCodeLoadCmd)
4509     return getStruct<MachO::linkedit_data_command>(*this, DataInCodeLoadCmd);
4510 
4511   // If there is no DataInCodeLoadCmd return a load command with zero'ed fields.
4512   MachO::linkedit_data_command Cmd;
4513   Cmd.cmd = MachO::LC_DATA_IN_CODE;
4514   Cmd.cmdsize = sizeof(MachO::linkedit_data_command);
4515   Cmd.dataoff = 0;
4516   Cmd.datasize = 0;
4517   return Cmd;
4518 }
4519 
4520 MachO::linkedit_data_command
4521 MachOObjectFile::getLinkOptHintsLoadCommand() const {
4522   if (LinkOptHintsLoadCmd)
4523     return getStruct<MachO::linkedit_data_command>(*this, LinkOptHintsLoadCmd);
4524 
4525   // If there is no LinkOptHintsLoadCmd return a load command with zero'ed
4526   // fields.
4527   MachO::linkedit_data_command Cmd;
4528   Cmd.cmd = MachO::LC_LINKER_OPTIMIZATION_HINT;
4529   Cmd.cmdsize = sizeof(MachO::linkedit_data_command);
4530   Cmd.dataoff = 0;
4531   Cmd.datasize = 0;
4532   return Cmd;
4533 }
4534 
4535 ArrayRef<uint8_t> MachOObjectFile::getDyldInfoRebaseOpcodes() const {
4536   if (!DyldInfoLoadCmd)
4537     return None;
4538 
4539   auto DyldInfoOrErr =
4540     getStructOrErr<MachO::dyld_info_command>(*this, DyldInfoLoadCmd);
4541   if (!DyldInfoOrErr)
4542     return None;
4543   MachO::dyld_info_command DyldInfo = DyldInfoOrErr.get();
4544   const uint8_t *Ptr =
4545       reinterpret_cast<const uint8_t *>(getPtr(*this, DyldInfo.rebase_off));
4546   return makeArrayRef(Ptr, DyldInfo.rebase_size);
4547 }
4548 
4549 ArrayRef<uint8_t> MachOObjectFile::getDyldInfoBindOpcodes() const {
4550   if (!DyldInfoLoadCmd)
4551     return None;
4552 
4553   auto DyldInfoOrErr =
4554     getStructOrErr<MachO::dyld_info_command>(*this, DyldInfoLoadCmd);
4555   if (!DyldInfoOrErr)
4556     return None;
4557   MachO::dyld_info_command DyldInfo = DyldInfoOrErr.get();
4558   const uint8_t *Ptr =
4559       reinterpret_cast<const uint8_t *>(getPtr(*this, DyldInfo.bind_off));
4560   return makeArrayRef(Ptr, DyldInfo.bind_size);
4561 }
4562 
4563 ArrayRef<uint8_t> MachOObjectFile::getDyldInfoWeakBindOpcodes() const {
4564   if (!DyldInfoLoadCmd)
4565     return None;
4566 
4567   auto DyldInfoOrErr =
4568     getStructOrErr<MachO::dyld_info_command>(*this, DyldInfoLoadCmd);
4569   if (!DyldInfoOrErr)
4570     return None;
4571   MachO::dyld_info_command DyldInfo = DyldInfoOrErr.get();
4572   const uint8_t *Ptr =
4573       reinterpret_cast<const uint8_t *>(getPtr(*this, DyldInfo.weak_bind_off));
4574   return makeArrayRef(Ptr, DyldInfo.weak_bind_size);
4575 }
4576 
4577 ArrayRef<uint8_t> MachOObjectFile::getDyldInfoLazyBindOpcodes() const {
4578   if (!DyldInfoLoadCmd)
4579     return None;
4580 
4581   auto DyldInfoOrErr =
4582     getStructOrErr<MachO::dyld_info_command>(*this, DyldInfoLoadCmd);
4583   if (!DyldInfoOrErr)
4584     return None;
4585   MachO::dyld_info_command DyldInfo = DyldInfoOrErr.get();
4586   const uint8_t *Ptr =
4587       reinterpret_cast<const uint8_t *>(getPtr(*this, DyldInfo.lazy_bind_off));
4588   return makeArrayRef(Ptr, DyldInfo.lazy_bind_size);
4589 }
4590 
4591 ArrayRef<uint8_t> MachOObjectFile::getDyldInfoExportsTrie() const {
4592   if (!DyldInfoLoadCmd)
4593     return None;
4594 
4595   auto DyldInfoOrErr =
4596     getStructOrErr<MachO::dyld_info_command>(*this, DyldInfoLoadCmd);
4597   if (!DyldInfoOrErr)
4598     return None;
4599   MachO::dyld_info_command DyldInfo = DyldInfoOrErr.get();
4600   const uint8_t *Ptr =
4601       reinterpret_cast<const uint8_t *>(getPtr(*this, DyldInfo.export_off));
4602   return makeArrayRef(Ptr, DyldInfo.export_size);
4603 }
4604 
4605 ArrayRef<uint8_t> MachOObjectFile::getUuid() const {
4606   if (!UuidLoadCmd)
4607     return None;
4608   // Returning a pointer is fine as uuid doesn't need endian swapping.
4609   const char *Ptr = UuidLoadCmd + offsetof(MachO::uuid_command, uuid);
4610   return makeArrayRef(reinterpret_cast<const uint8_t *>(Ptr), 16);
4611 }
4612 
4613 StringRef MachOObjectFile::getStringTableData() const {
4614   MachO::symtab_command S = getSymtabLoadCommand();
4615   return getData().substr(S.stroff, S.strsize);
4616 }
4617 
4618 bool MachOObjectFile::is64Bit() const {
4619   return getType() == getMachOType(false, true) ||
4620     getType() == getMachOType(true, true);
4621 }
4622 
4623 void MachOObjectFile::ReadULEB128s(uint64_t Index,
4624                                    SmallVectorImpl<uint64_t> &Out) const {
4625   DataExtractor extractor(ObjectFile::getData(), true, 0);
4626 
4627   uint64_t offset = Index;
4628   uint64_t data = 0;
4629   while (uint64_t delta = extractor.getULEB128(&offset)) {
4630     data += delta;
4631     Out.push_back(data);
4632   }
4633 }
4634 
4635 bool MachOObjectFile::isRelocatableObject() const {
4636   return getHeader().filetype == MachO::MH_OBJECT;
4637 }
4638 
4639 Expected<std::unique_ptr<MachOObjectFile>>
4640 ObjectFile::createMachOObjectFile(MemoryBufferRef Buffer,
4641                                   uint32_t UniversalCputype,
4642                                   uint32_t UniversalIndex) {
4643   StringRef Magic = Buffer.getBuffer().slice(0, 4);
4644   if (Magic == "\xFE\xED\xFA\xCE")
4645     return MachOObjectFile::create(Buffer, false, false,
4646                                    UniversalCputype, UniversalIndex);
4647   if (Magic == "\xCE\xFA\xED\xFE")
4648     return MachOObjectFile::create(Buffer, true, false,
4649                                    UniversalCputype, UniversalIndex);
4650   if (Magic == "\xFE\xED\xFA\xCF")
4651     return MachOObjectFile::create(Buffer, false, true,
4652                                    UniversalCputype, UniversalIndex);
4653   if (Magic == "\xCF\xFA\xED\xFE")
4654     return MachOObjectFile::create(Buffer, true, true,
4655                                    UniversalCputype, UniversalIndex);
4656   return make_error<GenericBinaryError>("Unrecognized MachO magic number",
4657                                         object_error::invalid_file_type);
4658 }
4659 
4660 StringRef MachOObjectFile::mapDebugSectionName(StringRef Name) const {
4661   return StringSwitch<StringRef>(Name)
4662       .Case("debug_str_offs", "debug_str_offsets")
4663       .Default(Name);
4664 }
4665