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 <system_error>
46 
47 using namespace llvm;
48 using namespace object;
49 
50 namespace {
51 
52   struct section_base {
53     char sectname[16];
54     char segname[16];
55   };
56 
57 } // end anonymous namespace
58 
malformedError(const Twine & Msg)59 static Error malformedError(const Twine &Msg) {
60   return make_error<GenericBinaryError>("truncated or malformed object (" +
61                                             Msg + ")",
62                                         object_error::parse_failed);
63 }
64 
65 // FIXME: Replace all uses of this function with getStructOrErr.
66 template <typename T>
getStruct(const MachOObjectFile & O,const char * P)67 static T getStruct(const MachOObjectFile &O, const char *P) {
68   // Don't read before the beginning or past the end of the file
69   if (P < O.getData().begin() || P + sizeof(T) > O.getData().end())
70     report_fatal_error("Malformed MachO file.");
71 
72   T Cmd;
73   memcpy(&Cmd, P, sizeof(T));
74   if (O.isLittleEndian() != sys::IsLittleEndianHost)
75     MachO::swapStruct(Cmd);
76   return Cmd;
77 }
78 
79 template <typename T>
getStructOrErr(const MachOObjectFile & O,const char * P)80 static Expected<T> getStructOrErr(const MachOObjectFile &O, const char *P) {
81   // Don't read before the beginning or past the end of the file
82   if (P < O.getData().begin() || P + sizeof(T) > O.getData().end())
83     return malformedError("Structure read out-of-range");
84 
85   T Cmd;
86   memcpy(&Cmd, P, sizeof(T));
87   if (O.isLittleEndian() != sys::IsLittleEndianHost)
88     MachO::swapStruct(Cmd);
89   return Cmd;
90 }
91 
92 static const char *
getSectionPtr(const MachOObjectFile & O,MachOObjectFile::LoadCommandInfo L,unsigned Sec)93 getSectionPtr(const MachOObjectFile &O, MachOObjectFile::LoadCommandInfo L,
94               unsigned Sec) {
95   uintptr_t CommandAddr = reinterpret_cast<uintptr_t>(L.Ptr);
96 
97   bool Is64 = O.is64Bit();
98   unsigned SegmentLoadSize = Is64 ? sizeof(MachO::segment_command_64) :
99                                     sizeof(MachO::segment_command);
100   unsigned SectionSize = Is64 ? sizeof(MachO::section_64) :
101                                 sizeof(MachO::section);
102 
103   uintptr_t SectionAddr = CommandAddr + SegmentLoadSize + Sec * SectionSize;
104   return reinterpret_cast<const char*>(SectionAddr);
105 }
106 
getPtr(const MachOObjectFile & O,size_t Offset)107 static const char *getPtr(const MachOObjectFile &O, size_t Offset) {
108   assert(Offset <= O.getData().size());
109   return O.getData().data() + Offset;
110 }
111 
112 static MachO::nlist_base
getSymbolTableEntryBase(const MachOObjectFile & O,DataRefImpl DRI)113 getSymbolTableEntryBase(const MachOObjectFile &O, DataRefImpl DRI) {
114   const char *P = reinterpret_cast<const char *>(DRI.p);
115   return getStruct<MachO::nlist_base>(O, P);
116 }
117 
parseSegmentOrSectionName(const char * P)118 static StringRef parseSegmentOrSectionName(const char *P) {
119   if (P[15] == 0)
120     // Null terminated.
121     return P;
122   // Not null terminated, so this is a 16 char string.
123   return StringRef(P, 16);
124 }
125 
getCPUType(const MachOObjectFile & O)126 static unsigned getCPUType(const MachOObjectFile &O) {
127   return O.getHeader().cputype;
128 }
129 
getCPUSubType(const MachOObjectFile & O)130 static unsigned getCPUSubType(const MachOObjectFile &O) {
131   return O.getHeader().cpusubtype;
132 }
133 
134 static uint32_t
getPlainRelocationAddress(const MachO::any_relocation_info & RE)135 getPlainRelocationAddress(const MachO::any_relocation_info &RE) {
136   return RE.r_word0;
137 }
138 
139 static unsigned
getScatteredRelocationAddress(const MachO::any_relocation_info & RE)140 getScatteredRelocationAddress(const MachO::any_relocation_info &RE) {
141   return RE.r_word0 & 0xffffff;
142 }
143 
getPlainRelocationPCRel(const MachOObjectFile & O,const MachO::any_relocation_info & RE)144 static bool getPlainRelocationPCRel(const MachOObjectFile &O,
145                                     const MachO::any_relocation_info &RE) {
146   if (O.isLittleEndian())
147     return (RE.r_word1 >> 24) & 1;
148   return (RE.r_word1 >> 7) & 1;
149 }
150 
151 static bool
getScatteredRelocationPCRel(const MachO::any_relocation_info & RE)152 getScatteredRelocationPCRel(const MachO::any_relocation_info &RE) {
153   return (RE.r_word0 >> 30) & 1;
154 }
155 
getPlainRelocationLength(const MachOObjectFile & O,const MachO::any_relocation_info & RE)156 static unsigned getPlainRelocationLength(const MachOObjectFile &O,
157                                          const MachO::any_relocation_info &RE) {
158   if (O.isLittleEndian())
159     return (RE.r_word1 >> 25) & 3;
160   return (RE.r_word1 >> 5) & 3;
161 }
162 
163 static unsigned
getScatteredRelocationLength(const MachO::any_relocation_info & RE)164 getScatteredRelocationLength(const MachO::any_relocation_info &RE) {
165   return (RE.r_word0 >> 28) & 3;
166 }
167 
getPlainRelocationType(const MachOObjectFile & O,const MachO::any_relocation_info & RE)168 static unsigned getPlainRelocationType(const MachOObjectFile &O,
169                                        const MachO::any_relocation_info &RE) {
170   if (O.isLittleEndian())
171     return RE.r_word1 >> 28;
172   return RE.r_word1 & 0xf;
173 }
174 
getSectionFlags(const MachOObjectFile & O,DataRefImpl Sec)175 static uint32_t getSectionFlags(const MachOObjectFile &O,
176                                 DataRefImpl Sec) {
177   if (O.is64Bit()) {
178     MachO::section_64 Sect = O.getSection64(Sec);
179     return Sect.flags;
180   }
181   MachO::section Sect = O.getSection(Sec);
182   return Sect.flags;
183 }
184 
185 static Expected<MachOObjectFile::LoadCommandInfo>
getLoadCommandInfo(const MachOObjectFile & Obj,const char * Ptr,uint32_t LoadCommandIndex)186 getLoadCommandInfo(const MachOObjectFile &Obj, const char *Ptr,
187                    uint32_t LoadCommandIndex) {
188   if (auto CmdOrErr = getStructOrErr<MachO::load_command>(Obj, Ptr)) {
189     if (CmdOrErr->cmdsize + Ptr > Obj.getData().end())
190       return malformedError("load command " + Twine(LoadCommandIndex) +
191                             " extends past end of file");
192     if (CmdOrErr->cmdsize < 8)
193       return malformedError("load command " + Twine(LoadCommandIndex) +
194                             " with size less than 8 bytes");
195     return MachOObjectFile::LoadCommandInfo({Ptr, *CmdOrErr});
196   } else
197     return CmdOrErr.takeError();
198 }
199 
200 static Expected<MachOObjectFile::LoadCommandInfo>
getFirstLoadCommandInfo(const MachOObjectFile & Obj)201 getFirstLoadCommandInfo(const MachOObjectFile &Obj) {
202   unsigned HeaderSize = Obj.is64Bit() ? sizeof(MachO::mach_header_64)
203                                       : sizeof(MachO::mach_header);
204   if (sizeof(MachO::load_command) > Obj.getHeader().sizeofcmds)
205     return malformedError("load command 0 extends past the end all load "
206                           "commands in the file");
207   return getLoadCommandInfo(Obj, getPtr(Obj, HeaderSize), 0);
208 }
209 
210 static Expected<MachOObjectFile::LoadCommandInfo>
getNextLoadCommandInfo(const MachOObjectFile & Obj,uint32_t LoadCommandIndex,const MachOObjectFile::LoadCommandInfo & L)211 getNextLoadCommandInfo(const MachOObjectFile &Obj, uint32_t LoadCommandIndex,
212                        const MachOObjectFile::LoadCommandInfo &L) {
213   unsigned HeaderSize = Obj.is64Bit() ? sizeof(MachO::mach_header_64)
214                                       : sizeof(MachO::mach_header);
215   if (L.Ptr + L.C.cmdsize + sizeof(MachO::load_command) >
216       Obj.getData().data() + HeaderSize + Obj.getHeader().sizeofcmds)
217     return malformedError("load command " + Twine(LoadCommandIndex + 1) +
218                           " extends past the end all load commands in the file");
219   return getLoadCommandInfo(Obj, L.Ptr + L.C.cmdsize, LoadCommandIndex + 1);
220 }
221 
222 template <typename T>
parseHeader(const MachOObjectFile & Obj,T & Header,Error & Err)223 static void parseHeader(const MachOObjectFile &Obj, T &Header,
224                         Error &Err) {
225   if (sizeof(T) > Obj.getData().size()) {
226     Err = malformedError("the mach header extends past the end of the "
227                          "file");
228     return;
229   }
230   if (auto HeaderOrErr = getStructOrErr<T>(Obj, getPtr(Obj, 0)))
231     Header = *HeaderOrErr;
232   else
233     Err = HeaderOrErr.takeError();
234 }
235 
236 // This is used to check for overlapping of Mach-O elements.
237 struct MachOElement {
238   uint64_t Offset;
239   uint64_t Size;
240   const char *Name;
241 };
242 
checkOverlappingElement(std::list<MachOElement> & Elements,uint64_t Offset,uint64_t Size,const char * Name)243 static Error checkOverlappingElement(std::list<MachOElement> &Elements,
244                                      uint64_t Offset, uint64_t Size,
245                                      const char *Name) {
246   if (Size == 0)
247     return Error::success();
248 
249   for (auto it=Elements.begin() ; it != Elements.end(); ++it) {
250     auto E = *it;
251     if ((Offset >= E.Offset && Offset < E.Offset + E.Size) ||
252         (Offset + Size > E.Offset && Offset + Size < E.Offset + E.Size) ||
253         (Offset <= E.Offset && Offset + Size >= E.Offset + E.Size))
254       return malformedError(Twine(Name) + " at offset " + Twine(Offset) +
255                             " with a size of " + Twine(Size) + ", overlaps " +
256                             E.Name + " at offset " + Twine(E.Offset) + " with "
257                             "a size of " + Twine(E.Size));
258     auto nt = it;
259     nt++;
260     if (nt != Elements.end()) {
261       auto N = *nt;
262       if (Offset + Size <= N.Offset) {
263         Elements.insert(nt, {Offset, Size, Name});
264         return Error::success();
265       }
266     }
267   }
268   Elements.push_back({Offset, Size, Name});
269   return Error::success();
270 }
271 
272 // Parses LC_SEGMENT or LC_SEGMENT_64 load command, adds addresses of all
273 // sections to \param Sections, and optionally sets
274 // \param IsPageZeroSegment to true.
275 template <typename Segment, typename Section>
parseSegmentLoadCommand(const MachOObjectFile & Obj,const MachOObjectFile::LoadCommandInfo & Load,SmallVectorImpl<const char * > & Sections,bool & IsPageZeroSegment,uint32_t LoadCommandIndex,const char * CmdName,uint64_t SizeOfHeaders,std::list<MachOElement> & Elements)276 static Error parseSegmentLoadCommand(
277     const MachOObjectFile &Obj, const MachOObjectFile::LoadCommandInfo &Load,
278     SmallVectorImpl<const char *> &Sections, bool &IsPageZeroSegment,
279     uint32_t LoadCommandIndex, const char *CmdName, uint64_t SizeOfHeaders,
280     std::list<MachOElement> &Elements) {
281   const unsigned SegmentLoadSize = sizeof(Segment);
282   if (Load.C.cmdsize < SegmentLoadSize)
283     return malformedError("load command " + Twine(LoadCommandIndex) +
284                           " " + CmdName + " cmdsize too small");
285   if (auto SegOrErr = getStructOrErr<Segment>(Obj, Load.Ptr)) {
286     Segment S = SegOrErr.get();
287     const unsigned SectionSize = sizeof(Section);
288     uint64_t FileSize = Obj.getData().size();
289     if (S.nsects > std::numeric_limits<uint32_t>::max() / SectionSize ||
290         S.nsects * SectionSize > Load.C.cmdsize - SegmentLoadSize)
291       return malformedError("load command " + Twine(LoadCommandIndex) +
292                             " inconsistent cmdsize in " + CmdName +
293                             " for the number of sections");
294     for (unsigned J = 0; J < S.nsects; ++J) {
295       const char *Sec = getSectionPtr(Obj, Load, J);
296       Sections.push_back(Sec);
297       auto SectionOrErr = getStructOrErr<Section>(Obj, Sec);
298       if (!SectionOrErr)
299         return SectionOrErr.takeError();
300       Section s = SectionOrErr.get();
301       if (Obj.getHeader().filetype != MachO::MH_DYLIB_STUB &&
302           Obj.getHeader().filetype != MachO::MH_DSYM &&
303           s.flags != MachO::S_ZEROFILL &&
304           s.flags != MachO::S_THREAD_LOCAL_ZEROFILL &&
305           s.offset > FileSize)
306         return malformedError("offset field of section " + Twine(J) + " in " +
307                               CmdName + " command " + Twine(LoadCommandIndex) +
308                               " extends past the end of the file");
309       if (Obj.getHeader().filetype != MachO::MH_DYLIB_STUB &&
310           Obj.getHeader().filetype != MachO::MH_DSYM &&
311           s.flags != MachO::S_ZEROFILL &&
312           s.flags != MachO::S_THREAD_LOCAL_ZEROFILL && S.fileoff == 0 &&
313           s.offset < SizeOfHeaders && s.size != 0)
314         return malformedError("offset field of section " + Twine(J) + " in " +
315                               CmdName + " command " + Twine(LoadCommandIndex) +
316                               " not past the headers of the file");
317       uint64_t BigSize = s.offset;
318       BigSize += s.size;
319       if (Obj.getHeader().filetype != MachO::MH_DYLIB_STUB &&
320           Obj.getHeader().filetype != MachO::MH_DSYM &&
321           s.flags != MachO::S_ZEROFILL &&
322           s.flags != MachO::S_THREAD_LOCAL_ZEROFILL &&
323           BigSize > FileSize)
324         return malformedError("offset field plus size field of section " +
325                               Twine(J) + " in " + CmdName + " command " +
326                               Twine(LoadCommandIndex) +
327                               " extends past the end of the file");
328       if (Obj.getHeader().filetype != MachO::MH_DYLIB_STUB &&
329           Obj.getHeader().filetype != MachO::MH_DSYM &&
330           s.flags != MachO::S_ZEROFILL &&
331           s.flags != MachO::S_THREAD_LOCAL_ZEROFILL &&
332           s.size > S.filesize)
333         return malformedError("size field of section " +
334                               Twine(J) + " in " + CmdName + " command " +
335                               Twine(LoadCommandIndex) +
336                               " greater than the segment");
337       if (Obj.getHeader().filetype != MachO::MH_DYLIB_STUB &&
338           Obj.getHeader().filetype != MachO::MH_DSYM && s.size != 0 &&
339           s.addr < S.vmaddr)
340         return malformedError("addr field of section " + Twine(J) + " in " +
341                               CmdName + " command " + Twine(LoadCommandIndex) +
342                               " less than the segment's vmaddr");
343       BigSize = s.addr;
344       BigSize += s.size;
345       uint64_t BigEnd = S.vmaddr;
346       BigEnd += S.vmsize;
347       if (S.vmsize != 0 && s.size != 0 && BigSize > BigEnd)
348         return malformedError("addr field plus size of section " + Twine(J) +
349                               " in " + CmdName + " command " +
350                               Twine(LoadCommandIndex) +
351                               " greater than than "
352                               "the segment's vmaddr plus vmsize");
353       if (Obj.getHeader().filetype != MachO::MH_DYLIB_STUB &&
354           Obj.getHeader().filetype != MachO::MH_DSYM &&
355           s.flags != MachO::S_ZEROFILL &&
356           s.flags != MachO::S_THREAD_LOCAL_ZEROFILL)
357         if (Error Err = checkOverlappingElement(Elements, s.offset, s.size,
358                                                 "section contents"))
359           return Err;
360       if (s.reloff > FileSize)
361         return malformedError("reloff field of section " + Twine(J) + " in " +
362                               CmdName + " command " + Twine(LoadCommandIndex) +
363                               " extends past the end of the file");
364       BigSize = s.nreloc;
365       BigSize *= sizeof(struct MachO::relocation_info);
366       BigSize += s.reloff;
367       if (BigSize > FileSize)
368         return malformedError("reloff field plus nreloc field times sizeof("
369                               "struct relocation_info) of section " +
370                               Twine(J) + " in " + CmdName + " command " +
371                               Twine(LoadCommandIndex) +
372                               " extends past the end of the file");
373       if (Error Err = checkOverlappingElement(Elements, s.reloff, s.nreloc *
374                                               sizeof(struct
375                                               MachO::relocation_info),
376                                               "section relocation entries"))
377         return Err;
378     }
379     if (S.fileoff > FileSize)
380       return malformedError("load command " + Twine(LoadCommandIndex) +
381                             " fileoff field in " + CmdName +
382                             " extends past the end of the file");
383     uint64_t BigSize = S.fileoff;
384     BigSize += S.filesize;
385     if (BigSize > FileSize)
386       return malformedError("load command " + Twine(LoadCommandIndex) +
387                             " fileoff field plus filesize field in " +
388                             CmdName + " extends past the end of the file");
389     if (S.vmsize != 0 && S.filesize > S.vmsize)
390       return malformedError("load command " + Twine(LoadCommandIndex) +
391                             " filesize field in " + CmdName +
392                             " greater than vmsize field");
393     IsPageZeroSegment |= StringRef("__PAGEZERO").equals(S.segname);
394   } else
395     return SegOrErr.takeError();
396 
397   return Error::success();
398 }
399 
checkSymtabCommand(const MachOObjectFile & Obj,const MachOObjectFile::LoadCommandInfo & Load,uint32_t LoadCommandIndex,const char ** SymtabLoadCmd,std::list<MachOElement> & Elements)400 static Error checkSymtabCommand(const MachOObjectFile &Obj,
401                                 const MachOObjectFile::LoadCommandInfo &Load,
402                                 uint32_t LoadCommandIndex,
403                                 const char **SymtabLoadCmd,
404                                 std::list<MachOElement> &Elements) {
405   if (Load.C.cmdsize < sizeof(MachO::symtab_command))
406     return malformedError("load command " + Twine(LoadCommandIndex) +
407                           " LC_SYMTAB cmdsize too small");
408   if (*SymtabLoadCmd != nullptr)
409     return malformedError("more than one LC_SYMTAB command");
410   auto SymtabOrErr = getStructOrErr<MachO::symtab_command>(Obj, Load.Ptr);
411   if (!SymtabOrErr)
412     return SymtabOrErr.takeError();
413   MachO::symtab_command Symtab = SymtabOrErr.get();
414   if (Symtab.cmdsize != sizeof(MachO::symtab_command))
415     return malformedError("LC_SYMTAB command " + Twine(LoadCommandIndex) +
416                           " has incorrect cmdsize");
417   uint64_t FileSize = Obj.getData().size();
418   if (Symtab.symoff > FileSize)
419     return malformedError("symoff field of LC_SYMTAB command " +
420                           Twine(LoadCommandIndex) + " extends past the end "
421                           "of the file");
422   uint64_t SymtabSize = Symtab.nsyms;
423   const char *struct_nlist_name;
424   if (Obj.is64Bit()) {
425     SymtabSize *= sizeof(MachO::nlist_64);
426     struct_nlist_name = "struct nlist_64";
427   } else {
428     SymtabSize *= sizeof(MachO::nlist);
429     struct_nlist_name = "struct nlist";
430   }
431   uint64_t BigSize = SymtabSize;
432   BigSize += Symtab.symoff;
433   if (BigSize > FileSize)
434     return malformedError("symoff field plus nsyms field times sizeof(" +
435                           Twine(struct_nlist_name) + ") of LC_SYMTAB command " +
436                           Twine(LoadCommandIndex) + " extends past the end "
437                           "of the file");
438   if (Error Err = checkOverlappingElement(Elements, Symtab.symoff, SymtabSize,
439                                           "symbol table"))
440     return Err;
441   if (Symtab.stroff > FileSize)
442     return malformedError("stroff field of LC_SYMTAB command " +
443                           Twine(LoadCommandIndex) + " extends past the end "
444                           "of the file");
445   BigSize = Symtab.stroff;
446   BigSize += Symtab.strsize;
447   if (BigSize > FileSize)
448     return malformedError("stroff field plus strsize field of LC_SYMTAB "
449                           "command " + Twine(LoadCommandIndex) + " extends "
450                           "past the end of the file");
451   if (Error Err = checkOverlappingElement(Elements, Symtab.stroff,
452                                           Symtab.strsize, "string table"))
453     return Err;
454   *SymtabLoadCmd = Load.Ptr;
455   return Error::success();
456 }
457 
checkDysymtabCommand(const MachOObjectFile & Obj,const MachOObjectFile::LoadCommandInfo & Load,uint32_t LoadCommandIndex,const char ** DysymtabLoadCmd,std::list<MachOElement> & Elements)458 static Error checkDysymtabCommand(const MachOObjectFile &Obj,
459                                   const MachOObjectFile::LoadCommandInfo &Load,
460                                   uint32_t LoadCommandIndex,
461                                   const char **DysymtabLoadCmd,
462                                   std::list<MachOElement> &Elements) {
463   if (Load.C.cmdsize < sizeof(MachO::dysymtab_command))
464     return malformedError("load command " + Twine(LoadCommandIndex) +
465                           " LC_DYSYMTAB cmdsize too small");
466   if (*DysymtabLoadCmd != nullptr)
467     return malformedError("more than one LC_DYSYMTAB command");
468   auto DysymtabOrErr =
469     getStructOrErr<MachO::dysymtab_command>(Obj, Load.Ptr);
470   if (!DysymtabOrErr)
471     return DysymtabOrErr.takeError();
472   MachO::dysymtab_command Dysymtab = DysymtabOrErr.get();
473   if (Dysymtab.cmdsize != sizeof(MachO::dysymtab_command))
474     return malformedError("LC_DYSYMTAB command " + Twine(LoadCommandIndex) +
475                           " has incorrect cmdsize");
476   uint64_t FileSize = Obj.getData().size();
477   if (Dysymtab.tocoff > FileSize)
478     return malformedError("tocoff field of LC_DYSYMTAB command " +
479                           Twine(LoadCommandIndex) + " extends past the end of "
480                           "the file");
481   uint64_t BigSize = Dysymtab.ntoc;
482   BigSize *= sizeof(MachO::dylib_table_of_contents);
483   BigSize += Dysymtab.tocoff;
484   if (BigSize > FileSize)
485     return malformedError("tocoff field plus ntoc field times sizeof(struct "
486                           "dylib_table_of_contents) of LC_DYSYMTAB command " +
487                           Twine(LoadCommandIndex) + " extends past the end of "
488                           "the file");
489   if (Error Err = checkOverlappingElement(Elements, Dysymtab.tocoff,
490                                           Dysymtab.ntoc * sizeof(struct
491                                           MachO::dylib_table_of_contents),
492                                           "table of contents"))
493     return Err;
494   if (Dysymtab.modtaboff > FileSize)
495     return malformedError("modtaboff field of LC_DYSYMTAB command " +
496                           Twine(LoadCommandIndex) + " extends past the end of "
497                           "the file");
498   BigSize = Dysymtab.nmodtab;
499   const char *struct_dylib_module_name;
500   uint64_t sizeof_modtab;
501   if (Obj.is64Bit()) {
502     sizeof_modtab = sizeof(MachO::dylib_module_64);
503     struct_dylib_module_name = "struct dylib_module_64";
504   } else {
505     sizeof_modtab = sizeof(MachO::dylib_module);
506     struct_dylib_module_name = "struct dylib_module";
507   }
508   BigSize *= sizeof_modtab;
509   BigSize += Dysymtab.modtaboff;
510   if (BigSize > FileSize)
511     return malformedError("modtaboff field plus nmodtab field times sizeof(" +
512                           Twine(struct_dylib_module_name) + ") of LC_DYSYMTAB "
513                           "command " + Twine(LoadCommandIndex) + " extends "
514                           "past the end of the file");
515   if (Error Err = checkOverlappingElement(Elements, Dysymtab.modtaboff,
516                                           Dysymtab.nmodtab * sizeof_modtab,
517                                           "module table"))
518     return Err;
519   if (Dysymtab.extrefsymoff > FileSize)
520     return malformedError("extrefsymoff field of LC_DYSYMTAB command " +
521                           Twine(LoadCommandIndex) + " extends past the end of "
522                           "the file");
523   BigSize = Dysymtab.nextrefsyms;
524   BigSize *= sizeof(MachO::dylib_reference);
525   BigSize += Dysymtab.extrefsymoff;
526   if (BigSize > FileSize)
527     return malformedError("extrefsymoff field plus nextrefsyms field times "
528                           "sizeof(struct dylib_reference) of LC_DYSYMTAB "
529                           "command " + Twine(LoadCommandIndex) + " extends "
530                           "past the end of the file");
531   if (Error Err = checkOverlappingElement(Elements, Dysymtab.extrefsymoff,
532                                           Dysymtab.nextrefsyms *
533                                               sizeof(MachO::dylib_reference),
534                                           "reference table"))
535     return Err;
536   if (Dysymtab.indirectsymoff > FileSize)
537     return malformedError("indirectsymoff field of LC_DYSYMTAB command " +
538                           Twine(LoadCommandIndex) + " extends past the end of "
539                           "the file");
540   BigSize = Dysymtab.nindirectsyms;
541   BigSize *= sizeof(uint32_t);
542   BigSize += Dysymtab.indirectsymoff;
543   if (BigSize > FileSize)
544     return malformedError("indirectsymoff field plus nindirectsyms field times "
545                           "sizeof(uint32_t) of LC_DYSYMTAB command " +
546                           Twine(LoadCommandIndex) + " extends past the end of "
547                           "the file");
548   if (Error Err = checkOverlappingElement(Elements, Dysymtab.indirectsymoff,
549                                           Dysymtab.nindirectsyms *
550                                           sizeof(uint32_t),
551                                           "indirect table"))
552     return Err;
553   if (Dysymtab.extreloff > FileSize)
554     return malformedError("extreloff field of LC_DYSYMTAB command " +
555                           Twine(LoadCommandIndex) + " extends past the end of "
556                           "the file");
557   BigSize = Dysymtab.nextrel;
558   BigSize *= sizeof(MachO::relocation_info);
559   BigSize += Dysymtab.extreloff;
560   if (BigSize > FileSize)
561     return malformedError("extreloff field plus nextrel field times sizeof"
562                           "(struct relocation_info) of LC_DYSYMTAB command " +
563                           Twine(LoadCommandIndex) + " extends past the end of "
564                           "the file");
565   if (Error Err = checkOverlappingElement(Elements, Dysymtab.extreloff,
566                                           Dysymtab.nextrel *
567                                               sizeof(MachO::relocation_info),
568                                           "external relocation table"))
569     return Err;
570   if (Dysymtab.locreloff > FileSize)
571     return malformedError("locreloff field of LC_DYSYMTAB command " +
572                           Twine(LoadCommandIndex) + " extends past the end of "
573                           "the file");
574   BigSize = Dysymtab.nlocrel;
575   BigSize *= sizeof(MachO::relocation_info);
576   BigSize += Dysymtab.locreloff;
577   if (BigSize > FileSize)
578     return malformedError("locreloff field plus nlocrel field times sizeof"
579                           "(struct relocation_info) of LC_DYSYMTAB command " +
580                           Twine(LoadCommandIndex) + " extends past the end of "
581                           "the file");
582   if (Error Err = checkOverlappingElement(Elements, Dysymtab.locreloff,
583                                           Dysymtab.nlocrel *
584                                               sizeof(MachO::relocation_info),
585                                           "local relocation table"))
586     return Err;
587   *DysymtabLoadCmd = Load.Ptr;
588   return Error::success();
589 }
590 
checkLinkeditDataCommand(const MachOObjectFile & Obj,const MachOObjectFile::LoadCommandInfo & Load,uint32_t LoadCommandIndex,const char ** LoadCmd,const char * CmdName,std::list<MachOElement> & Elements,const char * ElementName)591 static Error checkLinkeditDataCommand(const MachOObjectFile &Obj,
592                                  const MachOObjectFile::LoadCommandInfo &Load,
593                                  uint32_t LoadCommandIndex,
594                                  const char **LoadCmd, const char *CmdName,
595                                  std::list<MachOElement> &Elements,
596                                  const char *ElementName) {
597   if (Load.C.cmdsize < sizeof(MachO::linkedit_data_command))
598     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
599                           CmdName + " cmdsize too small");
600   if (*LoadCmd != nullptr)
601     return malformedError("more than one " + Twine(CmdName) + " command");
602   auto LinkDataOrError =
603     getStructOrErr<MachO::linkedit_data_command>(Obj, Load.Ptr);
604   if (!LinkDataOrError)
605     return LinkDataOrError.takeError();
606   MachO::linkedit_data_command LinkData = LinkDataOrError.get();
607   if (LinkData.cmdsize != sizeof(MachO::linkedit_data_command))
608     return malformedError(Twine(CmdName) + " command " +
609                           Twine(LoadCommandIndex) + " has incorrect cmdsize");
610   uint64_t FileSize = Obj.getData().size();
611   if (LinkData.dataoff > FileSize)
612     return malformedError("dataoff field of " + Twine(CmdName) + " command " +
613                           Twine(LoadCommandIndex) + " extends past the end of "
614                           "the file");
615   uint64_t BigSize = LinkData.dataoff;
616   BigSize += LinkData.datasize;
617   if (BigSize > FileSize)
618     return malformedError("dataoff field plus datasize field of " +
619                           Twine(CmdName) + " command " +
620                           Twine(LoadCommandIndex) + " extends past the end of "
621                           "the file");
622   if (Error Err = checkOverlappingElement(Elements, LinkData.dataoff,
623                                           LinkData.datasize, ElementName))
624     return Err;
625   *LoadCmd = Load.Ptr;
626   return Error::success();
627 }
628 
checkDyldInfoCommand(const MachOObjectFile & Obj,const MachOObjectFile::LoadCommandInfo & Load,uint32_t LoadCommandIndex,const char ** LoadCmd,const char * CmdName,std::list<MachOElement> & Elements)629 static Error checkDyldInfoCommand(const MachOObjectFile &Obj,
630                                   const MachOObjectFile::LoadCommandInfo &Load,
631                                   uint32_t LoadCommandIndex,
632                                   const char **LoadCmd, const char *CmdName,
633                                   std::list<MachOElement> &Elements) {
634   if (Load.C.cmdsize < sizeof(MachO::dyld_info_command))
635     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
636                           CmdName + " cmdsize too small");
637   if (*LoadCmd != nullptr)
638     return malformedError("more than one LC_DYLD_INFO and or LC_DYLD_INFO_ONLY "
639                           "command");
640   auto DyldInfoOrErr =
641     getStructOrErr<MachO::dyld_info_command>(Obj, Load.Ptr);
642   if (!DyldInfoOrErr)
643     return DyldInfoOrErr.takeError();
644   MachO::dyld_info_command DyldInfo = DyldInfoOrErr.get();
645   if (DyldInfo.cmdsize != sizeof(MachO::dyld_info_command))
646     return malformedError(Twine(CmdName) + " command " +
647                           Twine(LoadCommandIndex) + " has incorrect cmdsize");
648   uint64_t FileSize = Obj.getData().size();
649   if (DyldInfo.rebase_off > FileSize)
650     return malformedError("rebase_off field of " + Twine(CmdName) +
651                           " command " + Twine(LoadCommandIndex) + " extends "
652                           "past the end of the file");
653   uint64_t BigSize = DyldInfo.rebase_off;
654   BigSize += DyldInfo.rebase_size;
655   if (BigSize > FileSize)
656     return malformedError("rebase_off field plus rebase_size field of " +
657                           Twine(CmdName) + " command " +
658                           Twine(LoadCommandIndex) + " extends past the end of "
659                           "the file");
660   if (Error Err = checkOverlappingElement(Elements, DyldInfo.rebase_off,
661                                           DyldInfo.rebase_size,
662                                           "dyld rebase info"))
663     return Err;
664   if (DyldInfo.bind_off > FileSize)
665     return malformedError("bind_off field of " + Twine(CmdName) +
666                           " command " + Twine(LoadCommandIndex) + " extends "
667                           "past the end of the file");
668   BigSize = DyldInfo.bind_off;
669   BigSize += DyldInfo.bind_size;
670   if (BigSize > FileSize)
671     return malformedError("bind_off field plus bind_size field of " +
672                           Twine(CmdName) + " command " +
673                           Twine(LoadCommandIndex) + " extends past the end of "
674                           "the file");
675   if (Error Err = checkOverlappingElement(Elements, DyldInfo.bind_off,
676                                           DyldInfo.bind_size,
677                                           "dyld bind info"))
678     return Err;
679   if (DyldInfo.weak_bind_off > FileSize)
680     return malformedError("weak_bind_off field of " + Twine(CmdName) +
681                           " command " + Twine(LoadCommandIndex) + " extends "
682                           "past the end of the file");
683   BigSize = DyldInfo.weak_bind_off;
684   BigSize += DyldInfo.weak_bind_size;
685   if (BigSize > FileSize)
686     return malformedError("weak_bind_off field plus weak_bind_size field of " +
687                           Twine(CmdName) + " command " +
688                           Twine(LoadCommandIndex) + " extends past the end of "
689                           "the file");
690   if (Error Err = checkOverlappingElement(Elements, DyldInfo.weak_bind_off,
691                                           DyldInfo.weak_bind_size,
692                                           "dyld weak bind info"))
693     return Err;
694   if (DyldInfo.lazy_bind_off > FileSize)
695     return malformedError("lazy_bind_off field of " + Twine(CmdName) +
696                           " command " + Twine(LoadCommandIndex) + " extends "
697                           "past the end of the file");
698   BigSize = DyldInfo.lazy_bind_off;
699   BigSize += DyldInfo.lazy_bind_size;
700   if (BigSize > FileSize)
701     return malformedError("lazy_bind_off field plus lazy_bind_size field of " +
702                           Twine(CmdName) + " command " +
703                           Twine(LoadCommandIndex) + " extends past the end of "
704                           "the file");
705   if (Error Err = checkOverlappingElement(Elements, DyldInfo.lazy_bind_off,
706                                           DyldInfo.lazy_bind_size,
707                                           "dyld lazy bind info"))
708     return Err;
709   if (DyldInfo.export_off > FileSize)
710     return malformedError("export_off field of " + Twine(CmdName) +
711                           " command " + Twine(LoadCommandIndex) + " extends "
712                           "past the end of the file");
713   BigSize = DyldInfo.export_off;
714   BigSize += DyldInfo.export_size;
715   if (BigSize > FileSize)
716     return malformedError("export_off field plus export_size field of " +
717                           Twine(CmdName) + " command " +
718                           Twine(LoadCommandIndex) + " extends past the end of "
719                           "the file");
720   if (Error Err = checkOverlappingElement(Elements, DyldInfo.export_off,
721                                           DyldInfo.export_size,
722                                           "dyld export info"))
723     return Err;
724   *LoadCmd = Load.Ptr;
725   return Error::success();
726 }
727 
checkDylibCommand(const MachOObjectFile & Obj,const MachOObjectFile::LoadCommandInfo & Load,uint32_t LoadCommandIndex,const char * CmdName)728 static Error checkDylibCommand(const MachOObjectFile &Obj,
729                                const MachOObjectFile::LoadCommandInfo &Load,
730                                uint32_t LoadCommandIndex, const char *CmdName) {
731   if (Load.C.cmdsize < sizeof(MachO::dylib_command))
732     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
733                           CmdName + " cmdsize too small");
734   auto CommandOrErr = getStructOrErr<MachO::dylib_command>(Obj, Load.Ptr);
735   if (!CommandOrErr)
736     return CommandOrErr.takeError();
737   MachO::dylib_command D = CommandOrErr.get();
738   if (D.dylib.name < sizeof(MachO::dylib_command))
739     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
740                           CmdName + " name.offset field too small, not past "
741                           "the end of the dylib_command struct");
742   if (D.dylib.name >= D.cmdsize)
743     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
744                           CmdName + " name.offset field extends past the end "
745                           "of the load command");
746   // Make sure there is a null between the starting offset of the name and
747   // the end of the load command.
748   uint32_t i;
749   const char *P = (const char *)Load.Ptr;
750   for (i = D.dylib.name; i < D.cmdsize; i++)
751     if (P[i] == '\0')
752       break;
753   if (i >= D.cmdsize)
754     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
755                           CmdName + " library name extends past the end of the "
756                           "load command");
757   return Error::success();
758 }
759 
checkDylibIdCommand(const MachOObjectFile & Obj,const MachOObjectFile::LoadCommandInfo & Load,uint32_t LoadCommandIndex,const char ** LoadCmd)760 static Error checkDylibIdCommand(const MachOObjectFile &Obj,
761                                  const MachOObjectFile::LoadCommandInfo &Load,
762                                  uint32_t LoadCommandIndex,
763                                  const char **LoadCmd) {
764   if (Error Err = checkDylibCommand(Obj, Load, LoadCommandIndex,
765                                      "LC_ID_DYLIB"))
766     return Err;
767   if (*LoadCmd != nullptr)
768     return malformedError("more than one LC_ID_DYLIB command");
769   if (Obj.getHeader().filetype != MachO::MH_DYLIB &&
770       Obj.getHeader().filetype != MachO::MH_DYLIB_STUB)
771     return malformedError("LC_ID_DYLIB load command in non-dynamic library "
772                           "file type");
773   *LoadCmd = Load.Ptr;
774   return Error::success();
775 }
776 
checkDyldCommand(const MachOObjectFile & Obj,const MachOObjectFile::LoadCommandInfo & Load,uint32_t LoadCommandIndex,const char * CmdName)777 static Error checkDyldCommand(const MachOObjectFile &Obj,
778                               const MachOObjectFile::LoadCommandInfo &Load,
779                               uint32_t LoadCommandIndex, const char *CmdName) {
780   if (Load.C.cmdsize < sizeof(MachO::dylinker_command))
781     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
782                           CmdName + " cmdsize too small");
783   auto CommandOrErr = getStructOrErr<MachO::dylinker_command>(Obj, Load.Ptr);
784   if (!CommandOrErr)
785     return CommandOrErr.takeError();
786   MachO::dylinker_command D = CommandOrErr.get();
787   if (D.name < sizeof(MachO::dylinker_command))
788     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
789                           CmdName + " name.offset field too small, not past "
790                           "the end of the dylinker_command struct");
791   if (D.name >= D.cmdsize)
792     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
793                           CmdName + " name.offset field extends past the end "
794                           "of the load command");
795   // Make sure there is a null between the starting offset of the name and
796   // the end of the load command.
797   uint32_t i;
798   const char *P = (const char *)Load.Ptr;
799   for (i = D.name; i < D.cmdsize; i++)
800     if (P[i] == '\0')
801       break;
802   if (i >= D.cmdsize)
803     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
804                           CmdName + " dyld name extends past the end of the "
805                           "load command");
806   return Error::success();
807 }
808 
checkVersCommand(const MachOObjectFile & Obj,const MachOObjectFile::LoadCommandInfo & Load,uint32_t LoadCommandIndex,const char ** LoadCmd,const char * CmdName)809 static Error checkVersCommand(const MachOObjectFile &Obj,
810                               const MachOObjectFile::LoadCommandInfo &Load,
811                               uint32_t LoadCommandIndex,
812                               const char **LoadCmd, const char *CmdName) {
813   if (Load.C.cmdsize != sizeof(MachO::version_min_command))
814     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
815                           CmdName + " has incorrect cmdsize");
816   if (*LoadCmd != nullptr)
817     return malformedError("more than one LC_VERSION_MIN_MACOSX, "
818                           "LC_VERSION_MIN_IPHONEOS, LC_VERSION_MIN_TVOS or "
819                           "LC_VERSION_MIN_WATCHOS command");
820   *LoadCmd = Load.Ptr;
821   return Error::success();
822 }
823 
checkNoteCommand(const MachOObjectFile & Obj,const MachOObjectFile::LoadCommandInfo & Load,uint32_t LoadCommandIndex,std::list<MachOElement> & Elements)824 static Error checkNoteCommand(const MachOObjectFile &Obj,
825                               const MachOObjectFile::LoadCommandInfo &Load,
826                               uint32_t LoadCommandIndex,
827                               std::list<MachOElement> &Elements) {
828   if (Load.C.cmdsize != sizeof(MachO::note_command))
829     return malformedError("load command " + Twine(LoadCommandIndex) +
830                           " LC_NOTE has incorrect cmdsize");
831   auto NoteCmdOrErr = getStructOrErr<MachO::note_command>(Obj, Load.Ptr);
832   if (!NoteCmdOrErr)
833     return NoteCmdOrErr.takeError();
834   MachO::note_command Nt = NoteCmdOrErr.get();
835   uint64_t FileSize = Obj.getData().size();
836   if (Nt.offset > FileSize)
837     return malformedError("offset field of LC_NOTE command " +
838                           Twine(LoadCommandIndex) + " extends "
839                           "past the end of the file");
840   uint64_t BigSize = Nt.offset;
841   BigSize += Nt.size;
842   if (BigSize > FileSize)
843     return malformedError("size field plus offset field of LC_NOTE command " +
844                           Twine(LoadCommandIndex) + " extends past the end of "
845                           "the file");
846   if (Error Err = checkOverlappingElement(Elements, Nt.offset, Nt.size,
847                                           "LC_NOTE data"))
848     return Err;
849   return Error::success();
850 }
851 
852 static Error
parseBuildVersionCommand(const MachOObjectFile & Obj,const MachOObjectFile::LoadCommandInfo & Load,SmallVectorImpl<const char * > & BuildTools,uint32_t LoadCommandIndex)853 parseBuildVersionCommand(const MachOObjectFile &Obj,
854                          const MachOObjectFile::LoadCommandInfo &Load,
855                          SmallVectorImpl<const char*> &BuildTools,
856                          uint32_t LoadCommandIndex) {
857   auto BVCOrErr =
858     getStructOrErr<MachO::build_version_command>(Obj, Load.Ptr);
859   if (!BVCOrErr)
860     return BVCOrErr.takeError();
861   MachO::build_version_command BVC = BVCOrErr.get();
862   if (Load.C.cmdsize !=
863       sizeof(MachO::build_version_command) +
864           BVC.ntools * sizeof(MachO::build_tool_version))
865     return malformedError("load command " + Twine(LoadCommandIndex) +
866                           " LC_BUILD_VERSION_COMMAND has incorrect cmdsize");
867 
868   auto Start = Load.Ptr + sizeof(MachO::build_version_command);
869   BuildTools.resize(BVC.ntools);
870   for (unsigned i = 0; i < BVC.ntools; ++i)
871     BuildTools[i] = Start + i * sizeof(MachO::build_tool_version);
872 
873   return Error::success();
874 }
875 
checkRpathCommand(const MachOObjectFile & Obj,const MachOObjectFile::LoadCommandInfo & Load,uint32_t LoadCommandIndex)876 static Error checkRpathCommand(const MachOObjectFile &Obj,
877                                const MachOObjectFile::LoadCommandInfo &Load,
878                                uint32_t LoadCommandIndex) {
879   if (Load.C.cmdsize < sizeof(MachO::rpath_command))
880     return malformedError("load command " + Twine(LoadCommandIndex) +
881                           " LC_RPATH cmdsize too small");
882   auto ROrErr = getStructOrErr<MachO::rpath_command>(Obj, Load.Ptr);
883   if (!ROrErr)
884     return ROrErr.takeError();
885   MachO::rpath_command R = ROrErr.get();
886   if (R.path < sizeof(MachO::rpath_command))
887     return malformedError("load command " + Twine(LoadCommandIndex) +
888                           " LC_RPATH path.offset field too small, not past "
889                           "the end of the rpath_command struct");
890   if (R.path >= R.cmdsize)
891     return malformedError("load command " + Twine(LoadCommandIndex) +
892                           " LC_RPATH path.offset field extends past the end "
893                           "of the load command");
894   // Make sure there is a null between the starting offset of the path and
895   // the end of the load command.
896   uint32_t i;
897   const char *P = (const char *)Load.Ptr;
898   for (i = R.path; i < R.cmdsize; i++)
899     if (P[i] == '\0')
900       break;
901   if (i >= R.cmdsize)
902     return malformedError("load command " + Twine(LoadCommandIndex) +
903                           " LC_RPATH library name extends past the end of the "
904                           "load command");
905   return Error::success();
906 }
907 
checkEncryptCommand(const MachOObjectFile & Obj,const MachOObjectFile::LoadCommandInfo & Load,uint32_t LoadCommandIndex,uint64_t cryptoff,uint64_t cryptsize,const char ** LoadCmd,const char * CmdName)908 static Error checkEncryptCommand(const MachOObjectFile &Obj,
909                                  const MachOObjectFile::LoadCommandInfo &Load,
910                                  uint32_t LoadCommandIndex,
911                                  uint64_t cryptoff, uint64_t cryptsize,
912                                  const char **LoadCmd, const char *CmdName) {
913   if (*LoadCmd != nullptr)
914     return malformedError("more than one LC_ENCRYPTION_INFO and or "
915                           "LC_ENCRYPTION_INFO_64 command");
916   uint64_t FileSize = Obj.getData().size();
917   if (cryptoff > FileSize)
918     return malformedError("cryptoff field of " + Twine(CmdName) +
919                           " command " + Twine(LoadCommandIndex) + " extends "
920                           "past the end of the file");
921   uint64_t BigSize = cryptoff;
922   BigSize += cryptsize;
923   if (BigSize > FileSize)
924     return malformedError("cryptoff field plus cryptsize field of " +
925                           Twine(CmdName) + " command " +
926                           Twine(LoadCommandIndex) + " extends past the end of "
927                           "the file");
928   *LoadCmd = Load.Ptr;
929   return Error::success();
930 }
931 
checkLinkerOptCommand(const MachOObjectFile & Obj,const MachOObjectFile::LoadCommandInfo & Load,uint32_t LoadCommandIndex)932 static Error checkLinkerOptCommand(const MachOObjectFile &Obj,
933                                    const MachOObjectFile::LoadCommandInfo &Load,
934                                    uint32_t LoadCommandIndex) {
935   if (Load.C.cmdsize < sizeof(MachO::linker_option_command))
936     return malformedError("load command " + Twine(LoadCommandIndex) +
937                           " LC_LINKER_OPTION cmdsize too small");
938   auto LinkOptionOrErr =
939     getStructOrErr<MachO::linker_option_command>(Obj, Load.Ptr);
940   if (!LinkOptionOrErr)
941     return LinkOptionOrErr.takeError();
942   MachO::linker_option_command L = LinkOptionOrErr.get();
943   // Make sure the count of strings is correct.
944   const char *string = (const char *)Load.Ptr +
945                        sizeof(struct MachO::linker_option_command);
946   uint32_t left = L.cmdsize - sizeof(struct MachO::linker_option_command);
947   uint32_t i = 0;
948   while (left > 0) {
949     while (*string == '\0' && left > 0) {
950       string++;
951       left--;
952     }
953     if (left > 0) {
954       i++;
955       uint32_t NullPos = StringRef(string, left).find('\0');
956       if (0xffffffff == NullPos)
957         return malformedError("load command " + Twine(LoadCommandIndex) +
958                               " LC_LINKER_OPTION string #" + Twine(i) +
959                               " is not NULL terminated");
960       uint32_t len = std::min(NullPos, left) + 1;
961       string += len;
962       left -= len;
963     }
964   }
965   if (L.count != i)
966     return malformedError("load command " + Twine(LoadCommandIndex) +
967                           " LC_LINKER_OPTION string count " + Twine(L.count) +
968                           " does not match number of strings");
969   return Error::success();
970 }
971 
checkSubCommand(const MachOObjectFile & Obj,const MachOObjectFile::LoadCommandInfo & Load,uint32_t LoadCommandIndex,const char * CmdName,size_t SizeOfCmd,const char * CmdStructName,uint32_t PathOffset,const char * PathFieldName)972 static Error checkSubCommand(const MachOObjectFile &Obj,
973                              const MachOObjectFile::LoadCommandInfo &Load,
974                              uint32_t LoadCommandIndex, const char *CmdName,
975                              size_t SizeOfCmd, const char *CmdStructName,
976                              uint32_t PathOffset, const char *PathFieldName) {
977   if (PathOffset < SizeOfCmd)
978     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
979                           CmdName + " " + PathFieldName + ".offset field too "
980                           "small, not past the end of the " + CmdStructName);
981   if (PathOffset >= Load.C.cmdsize)
982     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
983                           CmdName + " " + PathFieldName + ".offset field "
984                           "extends past the end of the load command");
985   // Make sure there is a null between the starting offset of the path and
986   // the end of the load command.
987   uint32_t i;
988   const char *P = (const char *)Load.Ptr;
989   for (i = PathOffset; i < Load.C.cmdsize; i++)
990     if (P[i] == '\0')
991       break;
992   if (i >= Load.C.cmdsize)
993     return malformedError("load command " + Twine(LoadCommandIndex) + " " +
994                           CmdName + " " + PathFieldName + " name extends past "
995                           "the end of the load command");
996   return Error::success();
997 }
998 
checkThreadCommand(const MachOObjectFile & Obj,const MachOObjectFile::LoadCommandInfo & Load,uint32_t LoadCommandIndex,const char * CmdName)999 static Error checkThreadCommand(const MachOObjectFile &Obj,
1000                                 const MachOObjectFile::LoadCommandInfo &Load,
1001                                 uint32_t LoadCommandIndex,
1002                                 const char *CmdName) {
1003   if (Load.C.cmdsize < sizeof(MachO::thread_command))
1004     return malformedError("load command " + Twine(LoadCommandIndex) +
1005                           CmdName + " cmdsize too small");
1006   auto ThreadCommandOrErr =
1007     getStructOrErr<MachO::thread_command>(Obj, Load.Ptr);
1008   if (!ThreadCommandOrErr)
1009     return ThreadCommandOrErr.takeError();
1010   MachO::thread_command T = ThreadCommandOrErr.get();
1011   const char *state = Load.Ptr + sizeof(MachO::thread_command);
1012   const char *end = Load.Ptr + T.cmdsize;
1013   uint32_t nflavor = 0;
1014   uint32_t cputype = getCPUType(Obj);
1015   while (state < end) {
1016     if(state + sizeof(uint32_t) > end)
1017       return malformedError("load command " + Twine(LoadCommandIndex) +
1018                             "flavor in " + CmdName + " extends past end of "
1019                             "command");
1020     uint32_t flavor;
1021     memcpy(&flavor, state, sizeof(uint32_t));
1022     if (Obj.isLittleEndian() != sys::IsLittleEndianHost)
1023       sys::swapByteOrder(flavor);
1024     state += sizeof(uint32_t);
1025 
1026     if(state + sizeof(uint32_t) > end)
1027       return malformedError("load command " + Twine(LoadCommandIndex) +
1028                             " count in " + CmdName + " extends past end of "
1029                             "command");
1030     uint32_t count;
1031     memcpy(&count, state, sizeof(uint32_t));
1032     if (Obj.isLittleEndian() != sys::IsLittleEndianHost)
1033       sys::swapByteOrder(count);
1034     state += sizeof(uint32_t);
1035 
1036     if (cputype == MachO::CPU_TYPE_I386) {
1037       if (flavor == MachO::x86_THREAD_STATE32) {
1038         if (count != MachO::x86_THREAD_STATE32_COUNT)
1039           return malformedError("load command " + Twine(LoadCommandIndex) +
1040                                 " count not x86_THREAD_STATE32_COUNT for "
1041                                 "flavor number " + Twine(nflavor) + " which is "
1042                                 "a x86_THREAD_STATE32 flavor in " + CmdName +
1043                                 " command");
1044         if (state + sizeof(MachO::x86_thread_state32_t) > end)
1045           return malformedError("load command " + Twine(LoadCommandIndex) +
1046                                 " x86_THREAD_STATE32 extends past end of "
1047                                 "command in " + CmdName + " command");
1048         state += sizeof(MachO::x86_thread_state32_t);
1049       } else {
1050         return malformedError("load command " + Twine(LoadCommandIndex) +
1051                               " unknown flavor (" + Twine(flavor) + ") for "
1052                               "flavor number " + Twine(nflavor) + " in " +
1053                               CmdName + " command");
1054       }
1055     } else if (cputype == MachO::CPU_TYPE_X86_64) {
1056       if (flavor == MachO::x86_THREAD_STATE) {
1057         if (count != MachO::x86_THREAD_STATE_COUNT)
1058           return malformedError("load command " + Twine(LoadCommandIndex) +
1059                                 " count not x86_THREAD_STATE_COUNT for "
1060                                 "flavor number " + Twine(nflavor) + " which is "
1061                                 "a x86_THREAD_STATE flavor in " + CmdName +
1062                                 " command");
1063         if (state + sizeof(MachO::x86_thread_state_t) > end)
1064           return malformedError("load command " + Twine(LoadCommandIndex) +
1065                                 " x86_THREAD_STATE extends past end of "
1066                                 "command in " + CmdName + " command");
1067         state += sizeof(MachO::x86_thread_state_t);
1068       } else if (flavor == MachO::x86_FLOAT_STATE) {
1069         if (count != MachO::x86_FLOAT_STATE_COUNT)
1070           return malformedError("load command " + Twine(LoadCommandIndex) +
1071                                 " count not x86_FLOAT_STATE_COUNT for "
1072                                 "flavor number " + Twine(nflavor) + " which is "
1073                                 "a x86_FLOAT_STATE flavor in " + CmdName +
1074                                 " command");
1075         if (state + sizeof(MachO::x86_float_state_t) > end)
1076           return malformedError("load command " + Twine(LoadCommandIndex) +
1077                                 " x86_FLOAT_STATE extends past end of "
1078                                 "command in " + CmdName + " command");
1079         state += sizeof(MachO::x86_float_state_t);
1080       } else if (flavor == MachO::x86_EXCEPTION_STATE) {
1081         if (count != MachO::x86_EXCEPTION_STATE_COUNT)
1082           return malformedError("load command " + Twine(LoadCommandIndex) +
1083                                 " count not x86_EXCEPTION_STATE_COUNT for "
1084                                 "flavor number " + Twine(nflavor) + " which is "
1085                                 "a x86_EXCEPTION_STATE flavor in " + CmdName +
1086                                 " command");
1087         if (state + sizeof(MachO::x86_exception_state_t) > end)
1088           return malformedError("load command " + Twine(LoadCommandIndex) +
1089                                 " x86_EXCEPTION_STATE extends past end of "
1090                                 "command in " + CmdName + " command");
1091         state += sizeof(MachO::x86_exception_state_t);
1092       } else if (flavor == MachO::x86_THREAD_STATE64) {
1093         if (count != MachO::x86_THREAD_STATE64_COUNT)
1094           return malformedError("load command " + Twine(LoadCommandIndex) +
1095                                 " count not x86_THREAD_STATE64_COUNT for "
1096                                 "flavor number " + Twine(nflavor) + " which is "
1097                                 "a x86_THREAD_STATE64 flavor in " + CmdName +
1098                                 " command");
1099         if (state + sizeof(MachO::x86_thread_state64_t) > end)
1100           return malformedError("load command " + Twine(LoadCommandIndex) +
1101                                 " x86_THREAD_STATE64 extends past end of "
1102                                 "command in " + CmdName + " command");
1103         state += sizeof(MachO::x86_thread_state64_t);
1104       } else if (flavor == MachO::x86_EXCEPTION_STATE64) {
1105         if (count != MachO::x86_EXCEPTION_STATE64_COUNT)
1106           return malformedError("load command " + Twine(LoadCommandIndex) +
1107                                 " count not x86_EXCEPTION_STATE64_COUNT for "
1108                                 "flavor number " + Twine(nflavor) + " which is "
1109                                 "a x86_EXCEPTION_STATE64 flavor in " + CmdName +
1110                                 " command");
1111         if (state + sizeof(MachO::x86_exception_state64_t) > end)
1112           return malformedError("load command " + Twine(LoadCommandIndex) +
1113                                 " x86_EXCEPTION_STATE64 extends past end of "
1114                                 "command in " + CmdName + " command");
1115         state += sizeof(MachO::x86_exception_state64_t);
1116       } else {
1117         return malformedError("load command " + Twine(LoadCommandIndex) +
1118                               " unknown flavor (" + Twine(flavor) + ") for "
1119                               "flavor number " + Twine(nflavor) + " in " +
1120                               CmdName + " command");
1121       }
1122     } else if (cputype == MachO::CPU_TYPE_ARM) {
1123       if (flavor == MachO::ARM_THREAD_STATE) {
1124         if (count != MachO::ARM_THREAD_STATE_COUNT)
1125           return malformedError("load command " + Twine(LoadCommandIndex) +
1126                                 " count not ARM_THREAD_STATE_COUNT for "
1127                                 "flavor number " + Twine(nflavor) + " which is "
1128                                 "a ARM_THREAD_STATE flavor in " + CmdName +
1129                                 " command");
1130         if (state + sizeof(MachO::arm_thread_state32_t) > end)
1131           return malformedError("load command " + Twine(LoadCommandIndex) +
1132                                 " ARM_THREAD_STATE extends past end of "
1133                                 "command in " + CmdName + " command");
1134         state += sizeof(MachO::arm_thread_state32_t);
1135       } else {
1136         return malformedError("load command " + Twine(LoadCommandIndex) +
1137                               " unknown flavor (" + Twine(flavor) + ") for "
1138                               "flavor number " + Twine(nflavor) + " in " +
1139                               CmdName + " command");
1140       }
1141     } else if (cputype == MachO::CPU_TYPE_ARM64 ||
1142                cputype == MachO::CPU_TYPE_ARM64_32) {
1143       if (flavor == MachO::ARM_THREAD_STATE64) {
1144         if (count != MachO::ARM_THREAD_STATE64_COUNT)
1145           return malformedError("load command " + Twine(LoadCommandIndex) +
1146                                 " count not ARM_THREAD_STATE64_COUNT for "
1147                                 "flavor number " + Twine(nflavor) + " which is "
1148                                 "a ARM_THREAD_STATE64 flavor in " + CmdName +
1149                                 " command");
1150         if (state + sizeof(MachO::arm_thread_state64_t) > end)
1151           return malformedError("load command " + Twine(LoadCommandIndex) +
1152                                 " ARM_THREAD_STATE64 extends past end of "
1153                                 "command in " + CmdName + " command");
1154         state += sizeof(MachO::arm_thread_state64_t);
1155       } else {
1156         return malformedError("load command " + Twine(LoadCommandIndex) +
1157                               " unknown flavor (" + Twine(flavor) + ") for "
1158                               "flavor number " + Twine(nflavor) + " in " +
1159                               CmdName + " command");
1160       }
1161     } else if (cputype == MachO::CPU_TYPE_POWERPC) {
1162       if (flavor == MachO::PPC_THREAD_STATE) {
1163         if (count != MachO::PPC_THREAD_STATE_COUNT)
1164           return malformedError("load command " + Twine(LoadCommandIndex) +
1165                                 " count not PPC_THREAD_STATE_COUNT for "
1166                                 "flavor number " + Twine(nflavor) + " which is "
1167                                 "a PPC_THREAD_STATE flavor in " + CmdName +
1168                                 " command");
1169         if (state + sizeof(MachO::ppc_thread_state32_t) > end)
1170           return malformedError("load command " + Twine(LoadCommandIndex) +
1171                                 " PPC_THREAD_STATE extends past end of "
1172                                 "command in " + CmdName + " command");
1173         state += sizeof(MachO::ppc_thread_state32_t);
1174       } else {
1175         return malformedError("load command " + Twine(LoadCommandIndex) +
1176                               " unknown flavor (" + Twine(flavor) + ") for "
1177                               "flavor number " + Twine(nflavor) + " in " +
1178                               CmdName + " command");
1179       }
1180     } else {
1181       return malformedError("unknown cputype (" + Twine(cputype) + ") load "
1182                             "command " + Twine(LoadCommandIndex) + " for " +
1183                             CmdName + " command can't be checked");
1184     }
1185     nflavor++;
1186   }
1187   return Error::success();
1188 }
1189 
checkTwoLevelHintsCommand(const MachOObjectFile & Obj,const MachOObjectFile::LoadCommandInfo & Load,uint32_t LoadCommandIndex,const char ** LoadCmd,std::list<MachOElement> & Elements)1190 static Error checkTwoLevelHintsCommand(const MachOObjectFile &Obj,
1191                                        const MachOObjectFile::LoadCommandInfo
1192                                          &Load,
1193                                        uint32_t LoadCommandIndex,
1194                                        const char **LoadCmd,
1195                                        std::list<MachOElement> &Elements) {
1196   if (Load.C.cmdsize != sizeof(MachO::twolevel_hints_command))
1197     return malformedError("load command " + Twine(LoadCommandIndex) +
1198                           " LC_TWOLEVEL_HINTS has incorrect cmdsize");
1199   if (*LoadCmd != nullptr)
1200     return malformedError("more than one LC_TWOLEVEL_HINTS command");
1201   auto HintsOrErr = getStructOrErr<MachO::twolevel_hints_command>(Obj, Load.Ptr);
1202   if(!HintsOrErr)
1203     return HintsOrErr.takeError();
1204   MachO::twolevel_hints_command Hints = HintsOrErr.get();
1205   uint64_t FileSize = Obj.getData().size();
1206   if (Hints.offset > FileSize)
1207     return malformedError("offset field of LC_TWOLEVEL_HINTS command " +
1208                           Twine(LoadCommandIndex) + " extends past the end of "
1209                           "the file");
1210   uint64_t BigSize = Hints.nhints;
1211   BigSize *= sizeof(MachO::twolevel_hint);
1212   BigSize += Hints.offset;
1213   if (BigSize > FileSize)
1214     return malformedError("offset field plus nhints times sizeof(struct "
1215                           "twolevel_hint) field of LC_TWOLEVEL_HINTS command " +
1216                           Twine(LoadCommandIndex) + " extends past the end of "
1217                           "the file");
1218   if (Error Err = checkOverlappingElement(Elements, Hints.offset, Hints.nhints *
1219                                           sizeof(MachO::twolevel_hint),
1220                                           "two level hints"))
1221     return Err;
1222   *LoadCmd = Load.Ptr;
1223   return Error::success();
1224 }
1225 
1226 // Returns true if the libObject code does not support the load command and its
1227 // contents.  The cmd value it is treated as an unknown load command but with
1228 // an error message that says the cmd value is obsolete.
isLoadCommandObsolete(uint32_t cmd)1229 static bool isLoadCommandObsolete(uint32_t cmd) {
1230   if (cmd == MachO::LC_SYMSEG ||
1231       cmd == MachO::LC_LOADFVMLIB ||
1232       cmd == MachO::LC_IDFVMLIB ||
1233       cmd == MachO::LC_IDENT ||
1234       cmd == MachO::LC_FVMFILE ||
1235       cmd == MachO::LC_PREPAGE ||
1236       cmd == MachO::LC_PREBOUND_DYLIB ||
1237       cmd == MachO::LC_TWOLEVEL_HINTS ||
1238       cmd == MachO::LC_PREBIND_CKSUM)
1239     return true;
1240   return false;
1241 }
1242 
1243 Expected<std::unique_ptr<MachOObjectFile>>
create(MemoryBufferRef Object,bool IsLittleEndian,bool Is64Bits,uint32_t UniversalCputype,uint32_t UniversalIndex)1244 MachOObjectFile::create(MemoryBufferRef Object, bool IsLittleEndian,
1245                         bool Is64Bits, uint32_t UniversalCputype,
1246                         uint32_t UniversalIndex) {
1247   Error Err = Error::success();
1248   std::unique_ptr<MachOObjectFile> Obj(
1249       new MachOObjectFile(std::move(Object), IsLittleEndian,
1250                           Is64Bits, Err, UniversalCputype,
1251                           UniversalIndex));
1252   if (Err)
1253     return std::move(Err);
1254   return std::move(Obj);
1255 }
1256 
MachOObjectFile(MemoryBufferRef Object,bool IsLittleEndian,bool Is64bits,Error & Err,uint32_t UniversalCputype,uint32_t UniversalIndex)1257 MachOObjectFile::MachOObjectFile(MemoryBufferRef Object, bool IsLittleEndian,
1258                                  bool Is64bits, Error &Err,
1259                                  uint32_t UniversalCputype,
1260                                  uint32_t UniversalIndex)
1261     : ObjectFile(getMachOType(IsLittleEndian, Is64bits), Object) {
1262   ErrorAsOutParameter ErrAsOutParam(&Err);
1263   uint64_t SizeOfHeaders;
1264   uint32_t cputype;
1265   if (is64Bit()) {
1266     parseHeader(*this, Header64, Err);
1267     SizeOfHeaders = sizeof(MachO::mach_header_64);
1268     cputype = Header64.cputype;
1269   } else {
1270     parseHeader(*this, Header, Err);
1271     SizeOfHeaders = sizeof(MachO::mach_header);
1272     cputype = Header.cputype;
1273   }
1274   if (Err)
1275     return;
1276   SizeOfHeaders += getHeader().sizeofcmds;
1277   if (getData().data() + SizeOfHeaders > getData().end()) {
1278     Err = malformedError("load commands extend past the end of the file");
1279     return;
1280   }
1281   if (UniversalCputype != 0 && cputype != UniversalCputype) {
1282     Err = malformedError("universal header architecture: " +
1283                          Twine(UniversalIndex) + "'s cputype does not match "
1284                          "object file's mach header");
1285     return;
1286   }
1287   std::list<MachOElement> Elements;
1288   Elements.push_back({0, SizeOfHeaders, "Mach-O headers"});
1289 
1290   uint32_t LoadCommandCount = getHeader().ncmds;
1291   LoadCommandInfo Load;
1292   if (LoadCommandCount != 0) {
1293     if (auto LoadOrErr = getFirstLoadCommandInfo(*this))
1294       Load = *LoadOrErr;
1295     else {
1296       Err = LoadOrErr.takeError();
1297       return;
1298     }
1299   }
1300 
1301   const char *DyldIdLoadCmd = nullptr;
1302   const char *FuncStartsLoadCmd = nullptr;
1303   const char *SplitInfoLoadCmd = nullptr;
1304   const char *CodeSignDrsLoadCmd = nullptr;
1305   const char *CodeSignLoadCmd = nullptr;
1306   const char *VersLoadCmd = nullptr;
1307   const char *SourceLoadCmd = nullptr;
1308   const char *EntryPointLoadCmd = nullptr;
1309   const char *EncryptLoadCmd = nullptr;
1310   const char *RoutinesLoadCmd = nullptr;
1311   const char *UnixThreadLoadCmd = nullptr;
1312   const char *TwoLevelHintsLoadCmd = nullptr;
1313   for (unsigned I = 0; I < LoadCommandCount; ++I) {
1314     if (is64Bit()) {
1315       if (Load.C.cmdsize % 8 != 0) {
1316         // We have a hack here to allow 64-bit Mach-O core files to have
1317         // LC_THREAD commands that are only a multiple of 4 and not 8 to be
1318         // allowed since the macOS kernel produces them.
1319         if (getHeader().filetype != MachO::MH_CORE ||
1320             Load.C.cmd != MachO::LC_THREAD || Load.C.cmdsize % 4) {
1321           Err = malformedError("load command " + Twine(I) + " cmdsize not a "
1322                                "multiple of 8");
1323           return;
1324         }
1325       }
1326     } else {
1327       if (Load.C.cmdsize % 4 != 0) {
1328         Err = malformedError("load command " + Twine(I) + " cmdsize not a "
1329                              "multiple of 4");
1330         return;
1331       }
1332     }
1333     LoadCommands.push_back(Load);
1334     if (Load.C.cmd == MachO::LC_SYMTAB) {
1335       if ((Err = checkSymtabCommand(*this, Load, I, &SymtabLoadCmd, Elements)))
1336         return;
1337     } else if (Load.C.cmd == MachO::LC_DYSYMTAB) {
1338       if ((Err = checkDysymtabCommand(*this, Load, I, &DysymtabLoadCmd,
1339                                       Elements)))
1340         return;
1341     } else if (Load.C.cmd == MachO::LC_DATA_IN_CODE) {
1342       if ((Err = checkLinkeditDataCommand(*this, Load, I, &DataInCodeLoadCmd,
1343                                           "LC_DATA_IN_CODE", Elements,
1344                                           "data in code info")))
1345         return;
1346     } else if (Load.C.cmd == MachO::LC_LINKER_OPTIMIZATION_HINT) {
1347       if ((Err = checkLinkeditDataCommand(*this, Load, I, &LinkOptHintsLoadCmd,
1348                                           "LC_LINKER_OPTIMIZATION_HINT",
1349                                           Elements, "linker optimization "
1350                                           "hints")))
1351         return;
1352     } else if (Load.C.cmd == MachO::LC_FUNCTION_STARTS) {
1353       if ((Err = checkLinkeditDataCommand(*this, Load, I, &FuncStartsLoadCmd,
1354                                           "LC_FUNCTION_STARTS", Elements,
1355                                           "function starts data")))
1356         return;
1357     } else if (Load.C.cmd == MachO::LC_SEGMENT_SPLIT_INFO) {
1358       if ((Err = checkLinkeditDataCommand(*this, Load, I, &SplitInfoLoadCmd,
1359                                           "LC_SEGMENT_SPLIT_INFO", Elements,
1360                                           "split info data")))
1361         return;
1362     } else if (Load.C.cmd == MachO::LC_DYLIB_CODE_SIGN_DRS) {
1363       if ((Err = checkLinkeditDataCommand(*this, Load, I, &CodeSignDrsLoadCmd,
1364                                           "LC_DYLIB_CODE_SIGN_DRS", Elements,
1365                                           "code signing RDs data")))
1366         return;
1367     } else if (Load.C.cmd == MachO::LC_CODE_SIGNATURE) {
1368       if ((Err = checkLinkeditDataCommand(*this, Load, I, &CodeSignLoadCmd,
1369                                           "LC_CODE_SIGNATURE", Elements,
1370                                           "code signature data")))
1371         return;
1372     } else if (Load.C.cmd == MachO::LC_DYLD_INFO) {
1373       if ((Err = checkDyldInfoCommand(*this, Load, I, &DyldInfoLoadCmd,
1374                                       "LC_DYLD_INFO", Elements)))
1375         return;
1376     } else if (Load.C.cmd == MachO::LC_DYLD_INFO_ONLY) {
1377       if ((Err = checkDyldInfoCommand(*this, Load, I, &DyldInfoLoadCmd,
1378                                       "LC_DYLD_INFO_ONLY", Elements)))
1379         return;
1380     } else if (Load.C.cmd == MachO::LC_UUID) {
1381       if (Load.C.cmdsize != sizeof(MachO::uuid_command)) {
1382         Err = malformedError("LC_UUID command " + Twine(I) + " has incorrect "
1383                              "cmdsize");
1384         return;
1385       }
1386       if (UuidLoadCmd) {
1387         Err = malformedError("more than one LC_UUID command");
1388         return;
1389       }
1390       UuidLoadCmd = Load.Ptr;
1391     } else if (Load.C.cmd == MachO::LC_SEGMENT_64) {
1392       if ((Err = parseSegmentLoadCommand<MachO::segment_command_64,
1393                                          MachO::section_64>(
1394                    *this, Load, Sections, HasPageZeroSegment, I,
1395                    "LC_SEGMENT_64", SizeOfHeaders, Elements)))
1396         return;
1397     } else if (Load.C.cmd == MachO::LC_SEGMENT) {
1398       if ((Err = parseSegmentLoadCommand<MachO::segment_command,
1399                                          MachO::section>(
1400                    *this, Load, Sections, HasPageZeroSegment, I,
1401                    "LC_SEGMENT", SizeOfHeaders, Elements)))
1402         return;
1403     } else if (Load.C.cmd == MachO::LC_ID_DYLIB) {
1404       if ((Err = checkDylibIdCommand(*this, Load, I, &DyldIdLoadCmd)))
1405         return;
1406     } else if (Load.C.cmd == MachO::LC_LOAD_DYLIB) {
1407       if ((Err = checkDylibCommand(*this, Load, I, "LC_LOAD_DYLIB")))
1408         return;
1409       Libraries.push_back(Load.Ptr);
1410     } else if (Load.C.cmd == MachO::LC_LOAD_WEAK_DYLIB) {
1411       if ((Err = checkDylibCommand(*this, Load, I, "LC_LOAD_WEAK_DYLIB")))
1412         return;
1413       Libraries.push_back(Load.Ptr);
1414     } else if (Load.C.cmd == MachO::LC_LAZY_LOAD_DYLIB) {
1415       if ((Err = checkDylibCommand(*this, Load, I, "LC_LAZY_LOAD_DYLIB")))
1416         return;
1417       Libraries.push_back(Load.Ptr);
1418     } else if (Load.C.cmd == MachO::LC_REEXPORT_DYLIB) {
1419       if ((Err = checkDylibCommand(*this, Load, I, "LC_REEXPORT_DYLIB")))
1420         return;
1421       Libraries.push_back(Load.Ptr);
1422     } else if (Load.C.cmd == MachO::LC_LOAD_UPWARD_DYLIB) {
1423       if ((Err = checkDylibCommand(*this, Load, I, "LC_LOAD_UPWARD_DYLIB")))
1424         return;
1425       Libraries.push_back(Load.Ptr);
1426     } else if (Load.C.cmd == MachO::LC_ID_DYLINKER) {
1427       if ((Err = checkDyldCommand(*this, Load, I, "LC_ID_DYLINKER")))
1428         return;
1429     } else if (Load.C.cmd == MachO::LC_LOAD_DYLINKER) {
1430       if ((Err = checkDyldCommand(*this, Load, I, "LC_LOAD_DYLINKER")))
1431         return;
1432     } else if (Load.C.cmd == MachO::LC_DYLD_ENVIRONMENT) {
1433       if ((Err = checkDyldCommand(*this, Load, I, "LC_DYLD_ENVIRONMENT")))
1434         return;
1435     } else if (Load.C.cmd == MachO::LC_VERSION_MIN_MACOSX) {
1436       if ((Err = checkVersCommand(*this, Load, I, &VersLoadCmd,
1437                                   "LC_VERSION_MIN_MACOSX")))
1438         return;
1439     } else if (Load.C.cmd == MachO::LC_VERSION_MIN_IPHONEOS) {
1440       if ((Err = checkVersCommand(*this, Load, I, &VersLoadCmd,
1441                                   "LC_VERSION_MIN_IPHONEOS")))
1442         return;
1443     } else if (Load.C.cmd == MachO::LC_VERSION_MIN_TVOS) {
1444       if ((Err = checkVersCommand(*this, Load, I, &VersLoadCmd,
1445                                   "LC_VERSION_MIN_TVOS")))
1446         return;
1447     } else if (Load.C.cmd == MachO::LC_VERSION_MIN_WATCHOS) {
1448       if ((Err = checkVersCommand(*this, Load, I, &VersLoadCmd,
1449                                   "LC_VERSION_MIN_WATCHOS")))
1450         return;
1451     } else if (Load.C.cmd == MachO::LC_NOTE) {
1452       if ((Err = checkNoteCommand(*this, Load, I, Elements)))
1453         return;
1454     } else if (Load.C.cmd == MachO::LC_BUILD_VERSION) {
1455       if ((Err = parseBuildVersionCommand(*this, Load, BuildTools, I)))
1456         return;
1457     } else if (Load.C.cmd == MachO::LC_RPATH) {
1458       if ((Err = checkRpathCommand(*this, Load, I)))
1459         return;
1460     } else if (Load.C.cmd == MachO::LC_SOURCE_VERSION) {
1461       if (Load.C.cmdsize != sizeof(MachO::source_version_command)) {
1462         Err = malformedError("LC_SOURCE_VERSION command " + Twine(I) +
1463                              " has incorrect cmdsize");
1464         return;
1465       }
1466       if (SourceLoadCmd) {
1467         Err = malformedError("more than one LC_SOURCE_VERSION command");
1468         return;
1469       }
1470       SourceLoadCmd = Load.Ptr;
1471     } else if (Load.C.cmd == MachO::LC_MAIN) {
1472       if (Load.C.cmdsize != sizeof(MachO::entry_point_command)) {
1473         Err = malformedError("LC_MAIN command " + Twine(I) +
1474                              " has incorrect cmdsize");
1475         return;
1476       }
1477       if (EntryPointLoadCmd) {
1478         Err = malformedError("more than one LC_MAIN command");
1479         return;
1480       }
1481       EntryPointLoadCmd = Load.Ptr;
1482     } else if (Load.C.cmd == MachO::LC_ENCRYPTION_INFO) {
1483       if (Load.C.cmdsize != sizeof(MachO::encryption_info_command)) {
1484         Err = malformedError("LC_ENCRYPTION_INFO command " + Twine(I) +
1485                              " has incorrect cmdsize");
1486         return;
1487       }
1488       MachO::encryption_info_command E =
1489         getStruct<MachO::encryption_info_command>(*this, Load.Ptr);
1490       if ((Err = checkEncryptCommand(*this, Load, I, E.cryptoff, E.cryptsize,
1491                                      &EncryptLoadCmd, "LC_ENCRYPTION_INFO")))
1492         return;
1493     } else if (Load.C.cmd == MachO::LC_ENCRYPTION_INFO_64) {
1494       if (Load.C.cmdsize != sizeof(MachO::encryption_info_command_64)) {
1495         Err = malformedError("LC_ENCRYPTION_INFO_64 command " + Twine(I) +
1496                              " has incorrect cmdsize");
1497         return;
1498       }
1499       MachO::encryption_info_command_64 E =
1500         getStruct<MachO::encryption_info_command_64>(*this, Load.Ptr);
1501       if ((Err = checkEncryptCommand(*this, Load, I, E.cryptoff, E.cryptsize,
1502                                      &EncryptLoadCmd, "LC_ENCRYPTION_INFO_64")))
1503         return;
1504     } else if (Load.C.cmd == MachO::LC_LINKER_OPTION) {
1505       if ((Err = checkLinkerOptCommand(*this, Load, I)))
1506         return;
1507     } else if (Load.C.cmd == MachO::LC_SUB_FRAMEWORK) {
1508       if (Load.C.cmdsize < sizeof(MachO::sub_framework_command)) {
1509         Err =  malformedError("load command " + Twine(I) +
1510                               " LC_SUB_FRAMEWORK cmdsize too small");
1511         return;
1512       }
1513       MachO::sub_framework_command S =
1514         getStruct<MachO::sub_framework_command>(*this, Load.Ptr);
1515       if ((Err = checkSubCommand(*this, Load, I, "LC_SUB_FRAMEWORK",
1516                                  sizeof(MachO::sub_framework_command),
1517                                  "sub_framework_command", S.umbrella,
1518                                  "umbrella")))
1519         return;
1520     } else if (Load.C.cmd == MachO::LC_SUB_UMBRELLA) {
1521       if (Load.C.cmdsize < sizeof(MachO::sub_umbrella_command)) {
1522         Err =  malformedError("load command " + Twine(I) +
1523                               " LC_SUB_UMBRELLA cmdsize too small");
1524         return;
1525       }
1526       MachO::sub_umbrella_command S =
1527         getStruct<MachO::sub_umbrella_command>(*this, Load.Ptr);
1528       if ((Err = checkSubCommand(*this, Load, I, "LC_SUB_UMBRELLA",
1529                                  sizeof(MachO::sub_umbrella_command),
1530                                  "sub_umbrella_command", S.sub_umbrella,
1531                                  "sub_umbrella")))
1532         return;
1533     } else if (Load.C.cmd == MachO::LC_SUB_LIBRARY) {
1534       if (Load.C.cmdsize < sizeof(MachO::sub_library_command)) {
1535         Err =  malformedError("load command " + Twine(I) +
1536                               " LC_SUB_LIBRARY cmdsize too small");
1537         return;
1538       }
1539       MachO::sub_library_command S =
1540         getStruct<MachO::sub_library_command>(*this, Load.Ptr);
1541       if ((Err = checkSubCommand(*this, Load, I, "LC_SUB_LIBRARY",
1542                                  sizeof(MachO::sub_library_command),
1543                                  "sub_library_command", S.sub_library,
1544                                  "sub_library")))
1545         return;
1546     } else if (Load.C.cmd == MachO::LC_SUB_CLIENT) {
1547       if (Load.C.cmdsize < sizeof(MachO::sub_client_command)) {
1548         Err =  malformedError("load command " + Twine(I) +
1549                               " LC_SUB_CLIENT cmdsize too small");
1550         return;
1551       }
1552       MachO::sub_client_command S =
1553         getStruct<MachO::sub_client_command>(*this, Load.Ptr);
1554       if ((Err = checkSubCommand(*this, Load, I, "LC_SUB_CLIENT",
1555                                  sizeof(MachO::sub_client_command),
1556                                  "sub_client_command", S.client, "client")))
1557         return;
1558     } else if (Load.C.cmd == MachO::LC_ROUTINES) {
1559       if (Load.C.cmdsize != sizeof(MachO::routines_command)) {
1560         Err = malformedError("LC_ROUTINES command " + Twine(I) +
1561                              " has incorrect cmdsize");
1562         return;
1563       }
1564       if (RoutinesLoadCmd) {
1565         Err = malformedError("more than one LC_ROUTINES and or LC_ROUTINES_64 "
1566                              "command");
1567         return;
1568       }
1569       RoutinesLoadCmd = Load.Ptr;
1570     } else if (Load.C.cmd == MachO::LC_ROUTINES_64) {
1571       if (Load.C.cmdsize != sizeof(MachO::routines_command_64)) {
1572         Err = malformedError("LC_ROUTINES_64 command " + Twine(I) +
1573                              " has incorrect cmdsize");
1574         return;
1575       }
1576       if (RoutinesLoadCmd) {
1577         Err = malformedError("more than one LC_ROUTINES_64 and or LC_ROUTINES "
1578                              "command");
1579         return;
1580       }
1581       RoutinesLoadCmd = Load.Ptr;
1582     } else if (Load.C.cmd == MachO::LC_UNIXTHREAD) {
1583       if ((Err = checkThreadCommand(*this, Load, I, "LC_UNIXTHREAD")))
1584         return;
1585       if (UnixThreadLoadCmd) {
1586         Err = malformedError("more than one LC_UNIXTHREAD command");
1587         return;
1588       }
1589       UnixThreadLoadCmd = Load.Ptr;
1590     } else if (Load.C.cmd == MachO::LC_THREAD) {
1591       if ((Err = checkThreadCommand(*this, Load, I, "LC_THREAD")))
1592         return;
1593     // Note: LC_TWOLEVEL_HINTS is really obsolete and is not supported.
1594     } else if (Load.C.cmd == MachO::LC_TWOLEVEL_HINTS) {
1595        if ((Err = checkTwoLevelHintsCommand(*this, Load, I,
1596                                             &TwoLevelHintsLoadCmd, Elements)))
1597          return;
1598     } else if (Load.C.cmd == MachO::LC_IDENT) {
1599       // Note: LC_IDENT is ignored.
1600       continue;
1601     } else if (isLoadCommandObsolete(Load.C.cmd)) {
1602       Err = malformedError("load command " + Twine(I) + " for cmd value of: " +
1603                            Twine(Load.C.cmd) + " is obsolete and not "
1604                            "supported");
1605       return;
1606     }
1607     // TODO: generate a error for unknown load commands by default.  But still
1608     // need work out an approach to allow or not allow unknown values like this
1609     // as an option for some uses like lldb.
1610     if (I < LoadCommandCount - 1) {
1611       if (auto LoadOrErr = getNextLoadCommandInfo(*this, I, Load))
1612         Load = *LoadOrErr;
1613       else {
1614         Err = LoadOrErr.takeError();
1615         return;
1616       }
1617     }
1618   }
1619   if (!SymtabLoadCmd) {
1620     if (DysymtabLoadCmd) {
1621       Err = malformedError("contains LC_DYSYMTAB load command without a "
1622                            "LC_SYMTAB load command");
1623       return;
1624     }
1625   } else if (DysymtabLoadCmd) {
1626     MachO::symtab_command Symtab =
1627       getStruct<MachO::symtab_command>(*this, SymtabLoadCmd);
1628     MachO::dysymtab_command Dysymtab =
1629       getStruct<MachO::dysymtab_command>(*this, DysymtabLoadCmd);
1630     if (Dysymtab.nlocalsym != 0 && Dysymtab.ilocalsym > Symtab.nsyms) {
1631       Err = malformedError("ilocalsym in LC_DYSYMTAB load command "
1632                            "extends past the end of the symbol table");
1633       return;
1634     }
1635     uint64_t BigSize = Dysymtab.ilocalsym;
1636     BigSize += Dysymtab.nlocalsym;
1637     if (Dysymtab.nlocalsym != 0 && BigSize > Symtab.nsyms) {
1638       Err = malformedError("ilocalsym plus nlocalsym in LC_DYSYMTAB load "
1639                            "command extends past the end of the symbol table");
1640       return;
1641     }
1642     if (Dysymtab.nextdefsym != 0 && Dysymtab.iextdefsym > Symtab.nsyms) {
1643       Err = malformedError("iextdefsym in LC_DYSYMTAB load command "
1644                            "extends past the end of the symbol table");
1645       return;
1646     }
1647     BigSize = Dysymtab.iextdefsym;
1648     BigSize += Dysymtab.nextdefsym;
1649     if (Dysymtab.nextdefsym != 0 && BigSize > Symtab.nsyms) {
1650       Err = malformedError("iextdefsym plus nextdefsym in LC_DYSYMTAB "
1651                            "load command extends past the end of the symbol "
1652                            "table");
1653       return;
1654     }
1655     if (Dysymtab.nundefsym != 0 && Dysymtab.iundefsym > Symtab.nsyms) {
1656       Err = malformedError("iundefsym in LC_DYSYMTAB load command "
1657                            "extends past the end of the symbol table");
1658       return;
1659     }
1660     BigSize = Dysymtab.iundefsym;
1661     BigSize += Dysymtab.nundefsym;
1662     if (Dysymtab.nundefsym != 0 && BigSize > Symtab.nsyms) {
1663       Err = malformedError("iundefsym plus nundefsym in LC_DYSYMTAB load "
1664                            " command extends past the end of the symbol table");
1665       return;
1666     }
1667   }
1668   if ((getHeader().filetype == MachO::MH_DYLIB ||
1669        getHeader().filetype == MachO::MH_DYLIB_STUB) &&
1670        DyldIdLoadCmd == nullptr) {
1671     Err = malformedError("no LC_ID_DYLIB load command in dynamic library "
1672                          "filetype");
1673     return;
1674   }
1675   assert(LoadCommands.size() == LoadCommandCount);
1676 
1677   Err = Error::success();
1678 }
1679 
checkSymbolTable() const1680 Error MachOObjectFile::checkSymbolTable() const {
1681   uint32_t Flags = 0;
1682   if (is64Bit()) {
1683     MachO::mach_header_64 H_64 = MachOObjectFile::getHeader64();
1684     Flags = H_64.flags;
1685   } else {
1686     MachO::mach_header H = MachOObjectFile::getHeader();
1687     Flags = H.flags;
1688   }
1689   uint8_t NType = 0;
1690   uint8_t NSect = 0;
1691   uint16_t NDesc = 0;
1692   uint32_t NStrx = 0;
1693   uint64_t NValue = 0;
1694   uint32_t SymbolIndex = 0;
1695   MachO::symtab_command S = getSymtabLoadCommand();
1696   for (const SymbolRef &Symbol : symbols()) {
1697     DataRefImpl SymDRI = Symbol.getRawDataRefImpl();
1698     if (is64Bit()) {
1699       MachO::nlist_64 STE_64 = getSymbol64TableEntry(SymDRI);
1700       NType = STE_64.n_type;
1701       NSect = STE_64.n_sect;
1702       NDesc = STE_64.n_desc;
1703       NStrx = STE_64.n_strx;
1704       NValue = STE_64.n_value;
1705     } else {
1706       MachO::nlist STE = getSymbolTableEntry(SymDRI);
1707       NType = STE.n_type;
1708       NSect = STE.n_sect;
1709       NDesc = STE.n_desc;
1710       NStrx = STE.n_strx;
1711       NValue = STE.n_value;
1712     }
1713     if ((NType & MachO::N_STAB) == 0) {
1714       if ((NType & MachO::N_TYPE) == MachO::N_SECT) {
1715         if (NSect == 0 || NSect > Sections.size())
1716           return malformedError("bad section index: " + Twine((int)NSect) +
1717                                 " for symbol at index " + Twine(SymbolIndex));
1718       }
1719       if ((NType & MachO::N_TYPE) == MachO::N_INDR) {
1720         if (NValue >= S.strsize)
1721           return malformedError("bad n_value: " + Twine((int)NValue) + " past "
1722                                 "the end of string table, for N_INDR symbol at "
1723                                 "index " + Twine(SymbolIndex));
1724       }
1725       if ((Flags & MachO::MH_TWOLEVEL) == MachO::MH_TWOLEVEL &&
1726           (((NType & MachO::N_TYPE) == MachO::N_UNDF && NValue == 0) ||
1727            (NType & MachO::N_TYPE) == MachO::N_PBUD)) {
1728             uint32_t LibraryOrdinal = MachO::GET_LIBRARY_ORDINAL(NDesc);
1729             if (LibraryOrdinal != 0 &&
1730                 LibraryOrdinal != MachO::EXECUTABLE_ORDINAL &&
1731                 LibraryOrdinal != MachO::DYNAMIC_LOOKUP_ORDINAL &&
1732                 LibraryOrdinal - 1 >= Libraries.size() ) {
1733               return malformedError("bad library ordinal: " + Twine(LibraryOrdinal) +
1734                                     " for symbol at index " + Twine(SymbolIndex));
1735             }
1736           }
1737     }
1738     if (NStrx >= S.strsize)
1739       return malformedError("bad string table index: " + Twine((int)NStrx) +
1740                             " past the end of string table, for symbol at "
1741                             "index " + Twine(SymbolIndex));
1742     SymbolIndex++;
1743   }
1744   return Error::success();
1745 }
1746 
moveSymbolNext(DataRefImpl & Symb) const1747 void MachOObjectFile::moveSymbolNext(DataRefImpl &Symb) const {
1748   unsigned SymbolTableEntrySize = is64Bit() ?
1749     sizeof(MachO::nlist_64) :
1750     sizeof(MachO::nlist);
1751   Symb.p += SymbolTableEntrySize;
1752 }
1753 
getSymbolName(DataRefImpl Symb) const1754 Expected<StringRef> MachOObjectFile::getSymbolName(DataRefImpl Symb) const {
1755   StringRef StringTable = getStringTableData();
1756   MachO::nlist_base Entry = getSymbolTableEntryBase(*this, Symb);
1757   if (Entry.n_strx == 0)
1758     // A n_strx value of 0 indicates that no name is associated with a
1759     // particular symbol table entry.
1760     return StringRef();
1761   const char *Start = &StringTable.data()[Entry.n_strx];
1762   if (Start < getData().begin() || Start >= getData().end()) {
1763     return malformedError("bad string index: " + Twine(Entry.n_strx) +
1764                           " for symbol at index " + Twine(getSymbolIndex(Symb)));
1765   }
1766   return StringRef(Start);
1767 }
1768 
getSectionType(SectionRef Sec) const1769 unsigned MachOObjectFile::getSectionType(SectionRef Sec) const {
1770   DataRefImpl DRI = Sec.getRawDataRefImpl();
1771   uint32_t Flags = getSectionFlags(*this, DRI);
1772   return Flags & MachO::SECTION_TYPE;
1773 }
1774 
getNValue(DataRefImpl Sym) const1775 uint64_t MachOObjectFile::getNValue(DataRefImpl Sym) const {
1776   if (is64Bit()) {
1777     MachO::nlist_64 Entry = getSymbol64TableEntry(Sym);
1778     return Entry.n_value;
1779   }
1780   MachO::nlist Entry = getSymbolTableEntry(Sym);
1781   return Entry.n_value;
1782 }
1783 
1784 // getIndirectName() returns the name of the alias'ed symbol who's string table
1785 // index is in the n_value field.
getIndirectName(DataRefImpl Symb,StringRef & Res) const1786 std::error_code MachOObjectFile::getIndirectName(DataRefImpl Symb,
1787                                                  StringRef &Res) const {
1788   StringRef StringTable = getStringTableData();
1789   MachO::nlist_base Entry = getSymbolTableEntryBase(*this, Symb);
1790   if ((Entry.n_type & MachO::N_TYPE) != MachO::N_INDR)
1791     return object_error::parse_failed;
1792   uint64_t NValue = getNValue(Symb);
1793   if (NValue >= StringTable.size())
1794     return object_error::parse_failed;
1795   const char *Start = &StringTable.data()[NValue];
1796   Res = StringRef(Start);
1797   return std::error_code();
1798 }
1799 
getSymbolValueImpl(DataRefImpl Sym) const1800 uint64_t MachOObjectFile::getSymbolValueImpl(DataRefImpl Sym) const {
1801   return getNValue(Sym);
1802 }
1803 
getSymbolAddress(DataRefImpl Sym) const1804 Expected<uint64_t> MachOObjectFile::getSymbolAddress(DataRefImpl Sym) const {
1805   return getSymbolValue(Sym);
1806 }
1807 
getSymbolAlignment(DataRefImpl DRI) const1808 uint32_t MachOObjectFile::getSymbolAlignment(DataRefImpl DRI) const {
1809   uint32_t Flags = cantFail(getSymbolFlags(DRI));
1810   if (Flags & SymbolRef::SF_Common) {
1811     MachO::nlist_base Entry = getSymbolTableEntryBase(*this, DRI);
1812     return 1 << MachO::GET_COMM_ALIGN(Entry.n_desc);
1813   }
1814   return 0;
1815 }
1816 
getCommonSymbolSizeImpl(DataRefImpl DRI) const1817 uint64_t MachOObjectFile::getCommonSymbolSizeImpl(DataRefImpl DRI) const {
1818   return getNValue(DRI);
1819 }
1820 
1821 Expected<SymbolRef::Type>
getSymbolType(DataRefImpl Symb) const1822 MachOObjectFile::getSymbolType(DataRefImpl Symb) const {
1823   MachO::nlist_base Entry = getSymbolTableEntryBase(*this, Symb);
1824   uint8_t n_type = Entry.n_type;
1825 
1826   // If this is a STAB debugging symbol, we can do nothing more.
1827   if (n_type & MachO::N_STAB)
1828     return SymbolRef::ST_Debug;
1829 
1830   switch (n_type & MachO::N_TYPE) {
1831     case MachO::N_UNDF :
1832       return SymbolRef::ST_Unknown;
1833     case MachO::N_SECT :
1834       Expected<section_iterator> SecOrError = getSymbolSection(Symb);
1835       if (!SecOrError)
1836         return SecOrError.takeError();
1837       section_iterator Sec = *SecOrError;
1838       if (Sec == section_end())
1839         return SymbolRef::ST_Other;
1840       if (Sec->isData() || Sec->isBSS())
1841         return SymbolRef::ST_Data;
1842       return SymbolRef::ST_Function;
1843   }
1844   return SymbolRef::ST_Other;
1845 }
1846 
getSymbolFlags(DataRefImpl DRI) const1847 Expected<uint32_t> MachOObjectFile::getSymbolFlags(DataRefImpl DRI) const {
1848   MachO::nlist_base Entry = getSymbolTableEntryBase(*this, DRI);
1849 
1850   uint8_t MachOType = Entry.n_type;
1851   uint16_t MachOFlags = Entry.n_desc;
1852 
1853   uint32_t Result = SymbolRef::SF_None;
1854 
1855   if ((MachOType & MachO::N_TYPE) == MachO::N_INDR)
1856     Result |= SymbolRef::SF_Indirect;
1857 
1858   if (MachOType & MachO::N_STAB)
1859     Result |= SymbolRef::SF_FormatSpecific;
1860 
1861   if (MachOType & MachO::N_EXT) {
1862     Result |= SymbolRef::SF_Global;
1863     if ((MachOType & MachO::N_TYPE) == MachO::N_UNDF) {
1864       if (getNValue(DRI))
1865         Result |= SymbolRef::SF_Common;
1866       else
1867         Result |= SymbolRef::SF_Undefined;
1868     }
1869 
1870     if (!(MachOType & MachO::N_PEXT))
1871       Result |= SymbolRef::SF_Exported;
1872   }
1873 
1874   if (MachOFlags & (MachO::N_WEAK_REF | MachO::N_WEAK_DEF))
1875     Result |= SymbolRef::SF_Weak;
1876 
1877   if (MachOFlags & (MachO::N_ARM_THUMB_DEF))
1878     Result |= SymbolRef::SF_Thumb;
1879 
1880   if ((MachOType & MachO::N_TYPE) == MachO::N_ABS)
1881     Result |= SymbolRef::SF_Absolute;
1882 
1883   return Result;
1884 }
1885 
1886 Expected<section_iterator>
getSymbolSection(DataRefImpl Symb) const1887 MachOObjectFile::getSymbolSection(DataRefImpl Symb) const {
1888   MachO::nlist_base Entry = getSymbolTableEntryBase(*this, Symb);
1889   uint8_t index = Entry.n_sect;
1890 
1891   if (index == 0)
1892     return section_end();
1893   DataRefImpl DRI;
1894   DRI.d.a = index - 1;
1895   if (DRI.d.a >= Sections.size()){
1896     return malformedError("bad section index: " + Twine((int)index) +
1897                           " for symbol at index " + Twine(getSymbolIndex(Symb)));
1898   }
1899   return section_iterator(SectionRef(DRI, this));
1900 }
1901 
getSymbolSectionID(SymbolRef Sym) const1902 unsigned MachOObjectFile::getSymbolSectionID(SymbolRef Sym) const {
1903   MachO::nlist_base Entry =
1904       getSymbolTableEntryBase(*this, Sym.getRawDataRefImpl());
1905   return Entry.n_sect - 1;
1906 }
1907 
moveSectionNext(DataRefImpl & Sec) const1908 void MachOObjectFile::moveSectionNext(DataRefImpl &Sec) const {
1909   Sec.d.a++;
1910 }
1911 
getSectionName(DataRefImpl Sec) const1912 Expected<StringRef> MachOObjectFile::getSectionName(DataRefImpl Sec) const {
1913   ArrayRef<char> Raw = getSectionRawName(Sec);
1914   return parseSegmentOrSectionName(Raw.data());
1915 }
1916 
getSectionAddress(DataRefImpl Sec) const1917 uint64_t MachOObjectFile::getSectionAddress(DataRefImpl Sec) const {
1918   if (is64Bit())
1919     return getSection64(Sec).addr;
1920   return getSection(Sec).addr;
1921 }
1922 
getSectionIndex(DataRefImpl Sec) const1923 uint64_t MachOObjectFile::getSectionIndex(DataRefImpl Sec) const {
1924   return Sec.d.a;
1925 }
1926 
getSectionSize(DataRefImpl Sec) const1927 uint64_t MachOObjectFile::getSectionSize(DataRefImpl Sec) const {
1928   // In the case if a malformed Mach-O file where the section offset is past
1929   // the end of the file or some part of the section size is past the end of
1930   // the file return a size of zero or a size that covers the rest of the file
1931   // but does not extend past the end of the file.
1932   uint32_t SectOffset, SectType;
1933   uint64_t SectSize;
1934 
1935   if (is64Bit()) {
1936     MachO::section_64 Sect = getSection64(Sec);
1937     SectOffset = Sect.offset;
1938     SectSize = Sect.size;
1939     SectType = Sect.flags & MachO::SECTION_TYPE;
1940   } else {
1941     MachO::section Sect = getSection(Sec);
1942     SectOffset = Sect.offset;
1943     SectSize = Sect.size;
1944     SectType = Sect.flags & MachO::SECTION_TYPE;
1945   }
1946   if (SectType == MachO::S_ZEROFILL || SectType == MachO::S_GB_ZEROFILL)
1947     return SectSize;
1948   uint64_t FileSize = getData().size();
1949   if (SectOffset > FileSize)
1950     return 0;
1951   if (FileSize - SectOffset < SectSize)
1952     return FileSize - SectOffset;
1953   return SectSize;
1954 }
1955 
getSectionContents(uint32_t Offset,uint64_t Size) const1956 ArrayRef<uint8_t> MachOObjectFile::getSectionContents(uint32_t Offset,
1957                                                       uint64_t Size) const {
1958   return arrayRefFromStringRef(getData().substr(Offset, Size));
1959 }
1960 
1961 Expected<ArrayRef<uint8_t>>
getSectionContents(DataRefImpl Sec) const1962 MachOObjectFile::getSectionContents(DataRefImpl Sec) const {
1963   uint32_t Offset;
1964   uint64_t Size;
1965 
1966   if (is64Bit()) {
1967     MachO::section_64 Sect = getSection64(Sec);
1968     Offset = Sect.offset;
1969     Size = Sect.size;
1970   } else {
1971     MachO::section Sect = getSection(Sec);
1972     Offset = Sect.offset;
1973     Size = Sect.size;
1974   }
1975 
1976   return getSectionContents(Offset, Size);
1977 }
1978 
getSectionAlignment(DataRefImpl Sec) const1979 uint64_t MachOObjectFile::getSectionAlignment(DataRefImpl Sec) const {
1980   uint32_t Align;
1981   if (is64Bit()) {
1982     MachO::section_64 Sect = getSection64(Sec);
1983     Align = Sect.align;
1984   } else {
1985     MachO::section Sect = getSection(Sec);
1986     Align = Sect.align;
1987   }
1988 
1989   return uint64_t(1) << Align;
1990 }
1991 
getSection(unsigned SectionIndex) const1992 Expected<SectionRef> MachOObjectFile::getSection(unsigned SectionIndex) const {
1993   if (SectionIndex < 1 || SectionIndex > Sections.size())
1994     return malformedError("bad section index: " + Twine((int)SectionIndex));
1995 
1996   DataRefImpl DRI;
1997   DRI.d.a = SectionIndex - 1;
1998   return SectionRef(DRI, this);
1999 }
2000 
getSection(StringRef SectionName) const2001 Expected<SectionRef> MachOObjectFile::getSection(StringRef SectionName) const {
2002   for (const SectionRef &Section : sections()) {
2003     auto NameOrErr = Section.getName();
2004     if (!NameOrErr)
2005       return NameOrErr.takeError();
2006     if (*NameOrErr == SectionName)
2007       return Section;
2008   }
2009   return errorCodeToError(object_error::parse_failed);
2010 }
2011 
isSectionCompressed(DataRefImpl Sec) const2012 bool MachOObjectFile::isSectionCompressed(DataRefImpl Sec) const {
2013   return false;
2014 }
2015 
isSectionText(DataRefImpl Sec) const2016 bool MachOObjectFile::isSectionText(DataRefImpl Sec) const {
2017   uint32_t Flags = getSectionFlags(*this, Sec);
2018   return Flags & MachO::S_ATTR_PURE_INSTRUCTIONS;
2019 }
2020 
isSectionData(DataRefImpl Sec) const2021 bool MachOObjectFile::isSectionData(DataRefImpl Sec) const {
2022   uint32_t Flags = getSectionFlags(*this, Sec);
2023   unsigned SectionType = Flags & MachO::SECTION_TYPE;
2024   return !(Flags & MachO::S_ATTR_PURE_INSTRUCTIONS) &&
2025          !(SectionType == MachO::S_ZEROFILL ||
2026            SectionType == MachO::S_GB_ZEROFILL);
2027 }
2028 
isSectionBSS(DataRefImpl Sec) const2029 bool MachOObjectFile::isSectionBSS(DataRefImpl Sec) const {
2030   uint32_t Flags = getSectionFlags(*this, Sec);
2031   unsigned SectionType = Flags & MachO::SECTION_TYPE;
2032   return !(Flags & MachO::S_ATTR_PURE_INSTRUCTIONS) &&
2033          (SectionType == MachO::S_ZEROFILL ||
2034           SectionType == MachO::S_GB_ZEROFILL);
2035 }
2036 
isDebugSection(DataRefImpl Sec) const2037 bool MachOObjectFile::isDebugSection(DataRefImpl Sec) const {
2038   Expected<StringRef> SectionNameOrErr = getSectionName(Sec);
2039   if (!SectionNameOrErr) {
2040     // TODO: Report the error message properly.
2041     consumeError(SectionNameOrErr.takeError());
2042     return false;
2043   }
2044   StringRef SectionName = SectionNameOrErr.get();
2045   return SectionName.startswith("__debug") ||
2046          SectionName.startswith("__zdebug") ||
2047          SectionName.startswith("__apple") || SectionName == "__gdb_index" ||
2048          SectionName == "__swift_ast";
2049 }
2050 
getSectionID(SectionRef Sec) const2051 unsigned MachOObjectFile::getSectionID(SectionRef Sec) const {
2052   return Sec.getRawDataRefImpl().d.a;
2053 }
2054 
isSectionVirtual(DataRefImpl Sec) const2055 bool MachOObjectFile::isSectionVirtual(DataRefImpl Sec) const {
2056   uint32_t Flags = getSectionFlags(*this, Sec);
2057   unsigned SectionType = Flags & MachO::SECTION_TYPE;
2058   return SectionType == MachO::S_ZEROFILL ||
2059          SectionType == MachO::S_GB_ZEROFILL;
2060 }
2061 
isSectionBitcode(DataRefImpl Sec) const2062 bool MachOObjectFile::isSectionBitcode(DataRefImpl Sec) const {
2063   StringRef SegmentName = getSectionFinalSegmentName(Sec);
2064   if (Expected<StringRef> NameOrErr = getSectionName(Sec))
2065     return (SegmentName == "__LLVM" && *NameOrErr == "__bitcode");
2066   return false;
2067 }
2068 
isSectionStripped(DataRefImpl Sec) const2069 bool MachOObjectFile::isSectionStripped(DataRefImpl Sec) const {
2070   if (is64Bit())
2071     return getSection64(Sec).offset == 0;
2072   return getSection(Sec).offset == 0;
2073 }
2074 
section_rel_begin(DataRefImpl Sec) const2075 relocation_iterator MachOObjectFile::section_rel_begin(DataRefImpl Sec) const {
2076   DataRefImpl Ret;
2077   Ret.d.a = Sec.d.a;
2078   Ret.d.b = 0;
2079   return relocation_iterator(RelocationRef(Ret, this));
2080 }
2081 
2082 relocation_iterator
section_rel_end(DataRefImpl Sec) const2083 MachOObjectFile::section_rel_end(DataRefImpl Sec) const {
2084   uint32_t Num;
2085   if (is64Bit()) {
2086     MachO::section_64 Sect = getSection64(Sec);
2087     Num = Sect.nreloc;
2088   } else {
2089     MachO::section Sect = getSection(Sec);
2090     Num = Sect.nreloc;
2091   }
2092 
2093   DataRefImpl Ret;
2094   Ret.d.a = Sec.d.a;
2095   Ret.d.b = Num;
2096   return relocation_iterator(RelocationRef(Ret, this));
2097 }
2098 
extrel_begin() const2099 relocation_iterator MachOObjectFile::extrel_begin() const {
2100   DataRefImpl Ret;
2101   // for DYSYMTAB symbols, Ret.d.a == 0 for external relocations
2102   Ret.d.a = 0; // Would normally be a section index.
2103   Ret.d.b = 0; // Index into the external relocations
2104   return relocation_iterator(RelocationRef(Ret, this));
2105 }
2106 
extrel_end() const2107 relocation_iterator MachOObjectFile::extrel_end() const {
2108   MachO::dysymtab_command DysymtabLoadCmd = getDysymtabLoadCommand();
2109   DataRefImpl Ret;
2110   // for DYSYMTAB symbols, Ret.d.a == 0 for external relocations
2111   Ret.d.a = 0; // Would normally be a section index.
2112   Ret.d.b = DysymtabLoadCmd.nextrel; // Index into the external relocations
2113   return relocation_iterator(RelocationRef(Ret, this));
2114 }
2115 
locrel_begin() const2116 relocation_iterator MachOObjectFile::locrel_begin() const {
2117   DataRefImpl Ret;
2118   // for DYSYMTAB symbols, Ret.d.a == 1 for local relocations
2119   Ret.d.a = 1; // Would normally be a section index.
2120   Ret.d.b = 0; // Index into the local relocations
2121   return relocation_iterator(RelocationRef(Ret, this));
2122 }
2123 
locrel_end() const2124 relocation_iterator MachOObjectFile::locrel_end() const {
2125   MachO::dysymtab_command DysymtabLoadCmd = getDysymtabLoadCommand();
2126   DataRefImpl Ret;
2127   // for DYSYMTAB symbols, Ret.d.a == 1 for local relocations
2128   Ret.d.a = 1; // Would normally be a section index.
2129   Ret.d.b = DysymtabLoadCmd.nlocrel; // Index into the local relocations
2130   return relocation_iterator(RelocationRef(Ret, this));
2131 }
2132 
moveRelocationNext(DataRefImpl & Rel) const2133 void MachOObjectFile::moveRelocationNext(DataRefImpl &Rel) const {
2134   ++Rel.d.b;
2135 }
2136 
getRelocationOffset(DataRefImpl Rel) const2137 uint64_t MachOObjectFile::getRelocationOffset(DataRefImpl Rel) const {
2138   assert((getHeader().filetype == MachO::MH_OBJECT ||
2139           getHeader().filetype == MachO::MH_KEXT_BUNDLE) &&
2140          "Only implemented for MH_OBJECT && MH_KEXT_BUNDLE");
2141   MachO::any_relocation_info RE = getRelocation(Rel);
2142   return getAnyRelocationAddress(RE);
2143 }
2144 
2145 symbol_iterator
getRelocationSymbol(DataRefImpl Rel) const2146 MachOObjectFile::getRelocationSymbol(DataRefImpl Rel) const {
2147   MachO::any_relocation_info RE = getRelocation(Rel);
2148   if (isRelocationScattered(RE))
2149     return symbol_end();
2150 
2151   uint32_t SymbolIdx = getPlainRelocationSymbolNum(RE);
2152   bool isExtern = getPlainRelocationExternal(RE);
2153   if (!isExtern)
2154     return symbol_end();
2155 
2156   MachO::symtab_command S = getSymtabLoadCommand();
2157   unsigned SymbolTableEntrySize = is64Bit() ?
2158     sizeof(MachO::nlist_64) :
2159     sizeof(MachO::nlist);
2160   uint64_t Offset = S.symoff + SymbolIdx * SymbolTableEntrySize;
2161   DataRefImpl Sym;
2162   Sym.p = reinterpret_cast<uintptr_t>(getPtr(*this, Offset));
2163   return symbol_iterator(SymbolRef(Sym, this));
2164 }
2165 
2166 section_iterator
getRelocationSection(DataRefImpl Rel) const2167 MachOObjectFile::getRelocationSection(DataRefImpl Rel) const {
2168   return section_iterator(getAnyRelocationSection(getRelocation(Rel)));
2169 }
2170 
getRelocationType(DataRefImpl Rel) const2171 uint64_t MachOObjectFile::getRelocationType(DataRefImpl Rel) const {
2172   MachO::any_relocation_info RE = getRelocation(Rel);
2173   return getAnyRelocationType(RE);
2174 }
2175 
getRelocationTypeName(DataRefImpl Rel,SmallVectorImpl<char> & Result) const2176 void MachOObjectFile::getRelocationTypeName(
2177     DataRefImpl Rel, SmallVectorImpl<char> &Result) const {
2178   StringRef res;
2179   uint64_t RType = getRelocationType(Rel);
2180 
2181   unsigned Arch = this->getArch();
2182 
2183   switch (Arch) {
2184     case Triple::x86: {
2185       static const char *const Table[] =  {
2186         "GENERIC_RELOC_VANILLA",
2187         "GENERIC_RELOC_PAIR",
2188         "GENERIC_RELOC_SECTDIFF",
2189         "GENERIC_RELOC_PB_LA_PTR",
2190         "GENERIC_RELOC_LOCAL_SECTDIFF",
2191         "GENERIC_RELOC_TLV" };
2192 
2193       if (RType > 5)
2194         res = "Unknown";
2195       else
2196         res = Table[RType];
2197       break;
2198     }
2199     case Triple::x86_64: {
2200       static const char *const Table[] =  {
2201         "X86_64_RELOC_UNSIGNED",
2202         "X86_64_RELOC_SIGNED",
2203         "X86_64_RELOC_BRANCH",
2204         "X86_64_RELOC_GOT_LOAD",
2205         "X86_64_RELOC_GOT",
2206         "X86_64_RELOC_SUBTRACTOR",
2207         "X86_64_RELOC_SIGNED_1",
2208         "X86_64_RELOC_SIGNED_2",
2209         "X86_64_RELOC_SIGNED_4",
2210         "X86_64_RELOC_TLV" };
2211 
2212       if (RType > 9)
2213         res = "Unknown";
2214       else
2215         res = Table[RType];
2216       break;
2217     }
2218     case Triple::arm: {
2219       static const char *const Table[] =  {
2220         "ARM_RELOC_VANILLA",
2221         "ARM_RELOC_PAIR",
2222         "ARM_RELOC_SECTDIFF",
2223         "ARM_RELOC_LOCAL_SECTDIFF",
2224         "ARM_RELOC_PB_LA_PTR",
2225         "ARM_RELOC_BR24",
2226         "ARM_THUMB_RELOC_BR22",
2227         "ARM_THUMB_32BIT_BRANCH",
2228         "ARM_RELOC_HALF",
2229         "ARM_RELOC_HALF_SECTDIFF" };
2230 
2231       if (RType > 9)
2232         res = "Unknown";
2233       else
2234         res = Table[RType];
2235       break;
2236     }
2237     case Triple::aarch64:
2238     case Triple::aarch64_32: {
2239       static const char *const Table[] = {
2240         "ARM64_RELOC_UNSIGNED",           "ARM64_RELOC_SUBTRACTOR",
2241         "ARM64_RELOC_BRANCH26",           "ARM64_RELOC_PAGE21",
2242         "ARM64_RELOC_PAGEOFF12",          "ARM64_RELOC_GOT_LOAD_PAGE21",
2243         "ARM64_RELOC_GOT_LOAD_PAGEOFF12", "ARM64_RELOC_POINTER_TO_GOT",
2244         "ARM64_RELOC_TLVP_LOAD_PAGE21",   "ARM64_RELOC_TLVP_LOAD_PAGEOFF12",
2245         "ARM64_RELOC_ADDEND"
2246       };
2247 
2248       if (RType >= array_lengthof(Table))
2249         res = "Unknown";
2250       else
2251         res = Table[RType];
2252       break;
2253     }
2254     case Triple::ppc: {
2255       static const char *const Table[] =  {
2256         "PPC_RELOC_VANILLA",
2257         "PPC_RELOC_PAIR",
2258         "PPC_RELOC_BR14",
2259         "PPC_RELOC_BR24",
2260         "PPC_RELOC_HI16",
2261         "PPC_RELOC_LO16",
2262         "PPC_RELOC_HA16",
2263         "PPC_RELOC_LO14",
2264         "PPC_RELOC_SECTDIFF",
2265         "PPC_RELOC_PB_LA_PTR",
2266         "PPC_RELOC_HI16_SECTDIFF",
2267         "PPC_RELOC_LO16_SECTDIFF",
2268         "PPC_RELOC_HA16_SECTDIFF",
2269         "PPC_RELOC_JBSR",
2270         "PPC_RELOC_LO14_SECTDIFF",
2271         "PPC_RELOC_LOCAL_SECTDIFF" };
2272 
2273       if (RType > 15)
2274         res = "Unknown";
2275       else
2276         res = Table[RType];
2277       break;
2278     }
2279     case Triple::UnknownArch:
2280       res = "Unknown";
2281       break;
2282   }
2283   Result.append(res.begin(), res.end());
2284 }
2285 
getRelocationLength(DataRefImpl Rel) const2286 uint8_t MachOObjectFile::getRelocationLength(DataRefImpl Rel) const {
2287   MachO::any_relocation_info RE = getRelocation(Rel);
2288   return getAnyRelocationLength(RE);
2289 }
2290 
2291 //
2292 // guessLibraryShortName() is passed a name of a dynamic library and returns a
2293 // guess on what the short name is.  Then name is returned as a substring of the
2294 // StringRef Name passed in.  The name of the dynamic library is recognized as
2295 // a framework if it has one of the two following forms:
2296 //      Foo.framework/Versions/A/Foo
2297 //      Foo.framework/Foo
2298 // Where A and Foo can be any string.  And may contain a trailing suffix
2299 // starting with an underbar.  If the Name is recognized as a framework then
2300 // isFramework is set to true else it is set to false.  If the Name has a
2301 // suffix then Suffix is set to the substring in Name that contains the suffix
2302 // else it is set to a NULL StringRef.
2303 //
2304 // The Name of the dynamic library is recognized as a library name if it has
2305 // one of the two following forms:
2306 //      libFoo.A.dylib
2307 //      libFoo.dylib
2308 //
2309 // The library may have a suffix trailing the name Foo of the form:
2310 //      libFoo_profile.A.dylib
2311 //      libFoo_profile.dylib
2312 // These dyld image suffixes are separated from the short name by a '_'
2313 // character. Because the '_' character is commonly used to separate words in
2314 // filenames guessLibraryShortName() cannot reliably separate a dylib's short
2315 // name from an arbitrary image suffix; imagine if both the short name and the
2316 // suffix contains an '_' character! To better deal with this ambiguity,
2317 // guessLibraryShortName() will recognize only "_debug" and "_profile" as valid
2318 // Suffix values. Calling code needs to be tolerant of guessLibraryShortName()
2319 // guessing incorrectly.
2320 //
2321 // The Name of the dynamic library is also recognized as a library name if it
2322 // has the following form:
2323 //      Foo.qtx
2324 //
2325 // If the Name of the dynamic library is none of the forms above then a NULL
2326 // StringRef is returned.
guessLibraryShortName(StringRef Name,bool & isFramework,StringRef & Suffix)2327 StringRef MachOObjectFile::guessLibraryShortName(StringRef Name,
2328                                                  bool &isFramework,
2329                                                  StringRef &Suffix) {
2330   StringRef Foo, F, DotFramework, V, Dylib, Lib, Dot, Qtx;
2331   size_t a, b, c, d, Idx;
2332 
2333   isFramework = false;
2334   Suffix = StringRef();
2335 
2336   // Pull off the last component and make Foo point to it
2337   a = Name.rfind('/');
2338   if (a == Name.npos || a == 0)
2339     goto guess_library;
2340   Foo = Name.slice(a+1, Name.npos);
2341 
2342   // Look for a suffix starting with a '_'
2343   Idx = Foo.rfind('_');
2344   if (Idx != Foo.npos && Foo.size() >= 2) {
2345     Suffix = Foo.slice(Idx, Foo.npos);
2346     if (Suffix != "_debug" && Suffix != "_profile")
2347       Suffix = StringRef();
2348     else
2349       Foo = Foo.slice(0, Idx);
2350   }
2351 
2352   // First look for the form Foo.framework/Foo
2353   b = Name.rfind('/', a);
2354   if (b == Name.npos)
2355     Idx = 0;
2356   else
2357     Idx = b+1;
2358   F = Name.slice(Idx, Idx + Foo.size());
2359   DotFramework = Name.slice(Idx + Foo.size(),
2360                             Idx + Foo.size() + sizeof(".framework/")-1);
2361   if (F == Foo && DotFramework == ".framework/") {
2362     isFramework = true;
2363     return Foo;
2364   }
2365 
2366   // Next look for the form Foo.framework/Versions/A/Foo
2367   if (b == Name.npos)
2368     goto guess_library;
2369   c =  Name.rfind('/', b);
2370   if (c == Name.npos || c == 0)
2371     goto guess_library;
2372   V = Name.slice(c+1, Name.npos);
2373   if (!V.startswith("Versions/"))
2374     goto guess_library;
2375   d =  Name.rfind('/', c);
2376   if (d == Name.npos)
2377     Idx = 0;
2378   else
2379     Idx = d+1;
2380   F = Name.slice(Idx, Idx + Foo.size());
2381   DotFramework = Name.slice(Idx + Foo.size(),
2382                             Idx + Foo.size() + sizeof(".framework/")-1);
2383   if (F == Foo && DotFramework == ".framework/") {
2384     isFramework = true;
2385     return Foo;
2386   }
2387 
2388 guess_library:
2389   // pull off the suffix after the "." and make a point to it
2390   a = Name.rfind('.');
2391   if (a == Name.npos || a == 0)
2392     return StringRef();
2393   Dylib = Name.slice(a, Name.npos);
2394   if (Dylib != ".dylib")
2395     goto guess_qtx;
2396 
2397   // First pull off the version letter for the form Foo.A.dylib if any.
2398   if (a >= 3) {
2399     Dot = Name.slice(a-2, a-1);
2400     if (Dot == ".")
2401       a = a - 2;
2402   }
2403 
2404   b = Name.rfind('/', a);
2405   if (b == Name.npos)
2406     b = 0;
2407   else
2408     b = b+1;
2409   // ignore any suffix after an underbar like Foo_profile.A.dylib
2410   Idx = Name.rfind('_');
2411   if (Idx != Name.npos && Idx != b) {
2412     Lib = Name.slice(b, Idx);
2413     Suffix = Name.slice(Idx, a);
2414     if (Suffix != "_debug" && Suffix != "_profile") {
2415       Suffix = StringRef();
2416       Lib = Name.slice(b, a);
2417     }
2418   }
2419   else
2420     Lib = Name.slice(b, a);
2421   // There are incorrect library names of the form:
2422   // libATS.A_profile.dylib so check for these.
2423   if (Lib.size() >= 3) {
2424     Dot = Lib.slice(Lib.size()-2, Lib.size()-1);
2425     if (Dot == ".")
2426       Lib = Lib.slice(0, Lib.size()-2);
2427   }
2428   return Lib;
2429 
2430 guess_qtx:
2431   Qtx = Name.slice(a, Name.npos);
2432   if (Qtx != ".qtx")
2433     return StringRef();
2434   b = Name.rfind('/', a);
2435   if (b == Name.npos)
2436     Lib = Name.slice(0, a);
2437   else
2438     Lib = Name.slice(b+1, a);
2439   // There are library names of the form: QT.A.qtx so check for these.
2440   if (Lib.size() >= 3) {
2441     Dot = Lib.slice(Lib.size()-2, Lib.size()-1);
2442     if (Dot == ".")
2443       Lib = Lib.slice(0, Lib.size()-2);
2444   }
2445   return Lib;
2446 }
2447 
2448 // getLibraryShortNameByIndex() is used to get the short name of the library
2449 // for an undefined symbol in a linked Mach-O binary that was linked with the
2450 // normal two-level namespace default (that is MH_TWOLEVEL in the header).
2451 // It is passed the index (0 - based) of the library as translated from
2452 // GET_LIBRARY_ORDINAL (1 - based).
getLibraryShortNameByIndex(unsigned Index,StringRef & Res) const2453 std::error_code MachOObjectFile::getLibraryShortNameByIndex(unsigned Index,
2454                                                          StringRef &Res) const {
2455   if (Index >= Libraries.size())
2456     return object_error::parse_failed;
2457 
2458   // If the cache of LibrariesShortNames is not built up do that first for
2459   // all the Libraries.
2460   if (LibrariesShortNames.size() == 0) {
2461     for (unsigned i = 0; i < Libraries.size(); i++) {
2462       auto CommandOrErr =
2463         getStructOrErr<MachO::dylib_command>(*this, Libraries[i]);
2464       if (!CommandOrErr)
2465         return object_error::parse_failed;
2466       MachO::dylib_command D = CommandOrErr.get();
2467       if (D.dylib.name >= D.cmdsize)
2468         return object_error::parse_failed;
2469       const char *P = (const char *)(Libraries[i]) + D.dylib.name;
2470       StringRef Name = StringRef(P);
2471       if (D.dylib.name+Name.size() >= D.cmdsize)
2472         return object_error::parse_failed;
2473       StringRef Suffix;
2474       bool isFramework;
2475       StringRef shortName = guessLibraryShortName(Name, isFramework, Suffix);
2476       if (shortName.empty())
2477         LibrariesShortNames.push_back(Name);
2478       else
2479         LibrariesShortNames.push_back(shortName);
2480     }
2481   }
2482 
2483   Res = LibrariesShortNames[Index];
2484   return std::error_code();
2485 }
2486 
getLibraryCount() const2487 uint32_t MachOObjectFile::getLibraryCount() const {
2488   return Libraries.size();
2489 }
2490 
2491 section_iterator
getRelocationRelocatedSection(relocation_iterator Rel) const2492 MachOObjectFile::getRelocationRelocatedSection(relocation_iterator Rel) const {
2493   DataRefImpl Sec;
2494   Sec.d.a = Rel->getRawDataRefImpl().d.a;
2495   return section_iterator(SectionRef(Sec, this));
2496 }
2497 
symbol_begin() const2498 basic_symbol_iterator MachOObjectFile::symbol_begin() const {
2499   DataRefImpl DRI;
2500   MachO::symtab_command Symtab = getSymtabLoadCommand();
2501   if (!SymtabLoadCmd || Symtab.nsyms == 0)
2502     return basic_symbol_iterator(SymbolRef(DRI, this));
2503 
2504   return getSymbolByIndex(0);
2505 }
2506 
symbol_end() const2507 basic_symbol_iterator MachOObjectFile::symbol_end() const {
2508   DataRefImpl DRI;
2509   MachO::symtab_command Symtab = getSymtabLoadCommand();
2510   if (!SymtabLoadCmd || Symtab.nsyms == 0)
2511     return basic_symbol_iterator(SymbolRef(DRI, this));
2512 
2513   unsigned SymbolTableEntrySize = is64Bit() ?
2514     sizeof(MachO::nlist_64) :
2515     sizeof(MachO::nlist);
2516   unsigned Offset = Symtab.symoff +
2517     Symtab.nsyms * SymbolTableEntrySize;
2518   DRI.p = reinterpret_cast<uintptr_t>(getPtr(*this, Offset));
2519   return basic_symbol_iterator(SymbolRef(DRI, this));
2520 }
2521 
getSymbolByIndex(unsigned Index) const2522 symbol_iterator MachOObjectFile::getSymbolByIndex(unsigned Index) const {
2523   MachO::symtab_command Symtab = getSymtabLoadCommand();
2524   if (!SymtabLoadCmd || Index >= Symtab.nsyms)
2525     report_fatal_error("Requested symbol index is out of range.");
2526   unsigned SymbolTableEntrySize =
2527     is64Bit() ? sizeof(MachO::nlist_64) : sizeof(MachO::nlist);
2528   DataRefImpl DRI;
2529   DRI.p = reinterpret_cast<uintptr_t>(getPtr(*this, Symtab.symoff));
2530   DRI.p += Index * SymbolTableEntrySize;
2531   return basic_symbol_iterator(SymbolRef(DRI, this));
2532 }
2533 
getSymbolIndex(DataRefImpl Symb) const2534 uint64_t MachOObjectFile::getSymbolIndex(DataRefImpl Symb) const {
2535   MachO::symtab_command Symtab = getSymtabLoadCommand();
2536   if (!SymtabLoadCmd)
2537     report_fatal_error("getSymbolIndex() called with no symbol table symbol");
2538   unsigned SymbolTableEntrySize =
2539     is64Bit() ? sizeof(MachO::nlist_64) : sizeof(MachO::nlist);
2540   DataRefImpl DRIstart;
2541   DRIstart.p = reinterpret_cast<uintptr_t>(getPtr(*this, Symtab.symoff));
2542   uint64_t Index = (Symb.p - DRIstart.p) / SymbolTableEntrySize;
2543   return Index;
2544 }
2545 
section_begin() const2546 section_iterator MachOObjectFile::section_begin() const {
2547   DataRefImpl DRI;
2548   return section_iterator(SectionRef(DRI, this));
2549 }
2550 
section_end() const2551 section_iterator MachOObjectFile::section_end() const {
2552   DataRefImpl DRI;
2553   DRI.d.a = Sections.size();
2554   return section_iterator(SectionRef(DRI, this));
2555 }
2556 
getBytesInAddress() const2557 uint8_t MachOObjectFile::getBytesInAddress() const {
2558   return is64Bit() ? 8 : 4;
2559 }
2560 
getFileFormatName() const2561 StringRef MachOObjectFile::getFileFormatName() const {
2562   unsigned CPUType = getCPUType(*this);
2563   if (!is64Bit()) {
2564     switch (CPUType) {
2565     case MachO::CPU_TYPE_I386:
2566       return "Mach-O 32-bit i386";
2567     case MachO::CPU_TYPE_ARM:
2568       return "Mach-O arm";
2569     case MachO::CPU_TYPE_ARM64_32:
2570       return "Mach-O arm64 (ILP32)";
2571     case MachO::CPU_TYPE_POWERPC:
2572       return "Mach-O 32-bit ppc";
2573     default:
2574       return "Mach-O 32-bit unknown";
2575     }
2576   }
2577 
2578   switch (CPUType) {
2579   case MachO::CPU_TYPE_X86_64:
2580     return "Mach-O 64-bit x86-64";
2581   case MachO::CPU_TYPE_ARM64:
2582     return "Mach-O arm64";
2583   case MachO::CPU_TYPE_POWERPC64:
2584     return "Mach-O 64-bit ppc64";
2585   default:
2586     return "Mach-O 64-bit unknown";
2587   }
2588 }
2589 
getArch(uint32_t CPUType,uint32_t CPUSubType)2590 Triple::ArchType MachOObjectFile::getArch(uint32_t CPUType, uint32_t CPUSubType) {
2591   switch (CPUType) {
2592   case MachO::CPU_TYPE_I386:
2593     return Triple::x86;
2594   case MachO::CPU_TYPE_X86_64:
2595     return Triple::x86_64;
2596   case MachO::CPU_TYPE_ARM:
2597     return Triple::arm;
2598   case MachO::CPU_TYPE_ARM64:
2599     return Triple::aarch64;
2600   case MachO::CPU_TYPE_ARM64_32:
2601     return Triple::aarch64_32;
2602   case MachO::CPU_TYPE_POWERPC:
2603     return Triple::ppc;
2604   case MachO::CPU_TYPE_POWERPC64:
2605     return Triple::ppc64;
2606   default:
2607     return Triple::UnknownArch;
2608   }
2609 }
2610 
getArchTriple(uint32_t CPUType,uint32_t CPUSubType,const char ** McpuDefault,const char ** ArchFlag)2611 Triple MachOObjectFile::getArchTriple(uint32_t CPUType, uint32_t CPUSubType,
2612                                       const char **McpuDefault,
2613                                       const char **ArchFlag) {
2614   if (McpuDefault)
2615     *McpuDefault = nullptr;
2616   if (ArchFlag)
2617     *ArchFlag = nullptr;
2618 
2619   switch (CPUType) {
2620   case MachO::CPU_TYPE_I386:
2621     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
2622     case MachO::CPU_SUBTYPE_I386_ALL:
2623       if (ArchFlag)
2624         *ArchFlag = "i386";
2625       return Triple("i386-apple-darwin");
2626     default:
2627       return Triple();
2628     }
2629   case MachO::CPU_TYPE_X86_64:
2630     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
2631     case MachO::CPU_SUBTYPE_X86_64_ALL:
2632       if (ArchFlag)
2633         *ArchFlag = "x86_64";
2634       return Triple("x86_64-apple-darwin");
2635     case MachO::CPU_SUBTYPE_X86_64_H:
2636       if (ArchFlag)
2637         *ArchFlag = "x86_64h";
2638       return Triple("x86_64h-apple-darwin");
2639     default:
2640       return Triple();
2641     }
2642   case MachO::CPU_TYPE_ARM:
2643     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
2644     case MachO::CPU_SUBTYPE_ARM_V4T:
2645       if (ArchFlag)
2646         *ArchFlag = "armv4t";
2647       return Triple("armv4t-apple-darwin");
2648     case MachO::CPU_SUBTYPE_ARM_V5TEJ:
2649       if (ArchFlag)
2650         *ArchFlag = "armv5e";
2651       return Triple("armv5e-apple-darwin");
2652     case MachO::CPU_SUBTYPE_ARM_XSCALE:
2653       if (ArchFlag)
2654         *ArchFlag = "xscale";
2655       return Triple("xscale-apple-darwin");
2656     case MachO::CPU_SUBTYPE_ARM_V6:
2657       if (ArchFlag)
2658         *ArchFlag = "armv6";
2659       return Triple("armv6-apple-darwin");
2660     case MachO::CPU_SUBTYPE_ARM_V6M:
2661       if (McpuDefault)
2662         *McpuDefault = "cortex-m0";
2663       if (ArchFlag)
2664         *ArchFlag = "armv6m";
2665       return Triple("armv6m-apple-darwin");
2666     case MachO::CPU_SUBTYPE_ARM_V7:
2667       if (ArchFlag)
2668         *ArchFlag = "armv7";
2669       return Triple("armv7-apple-darwin");
2670     case MachO::CPU_SUBTYPE_ARM_V7EM:
2671       if (McpuDefault)
2672         *McpuDefault = "cortex-m4";
2673       if (ArchFlag)
2674         *ArchFlag = "armv7em";
2675       return Triple("thumbv7em-apple-darwin");
2676     case MachO::CPU_SUBTYPE_ARM_V7K:
2677       if (McpuDefault)
2678         *McpuDefault = "cortex-a7";
2679       if (ArchFlag)
2680         *ArchFlag = "armv7k";
2681       return Triple("armv7k-apple-darwin");
2682     case MachO::CPU_SUBTYPE_ARM_V7M:
2683       if (McpuDefault)
2684         *McpuDefault = "cortex-m3";
2685       if (ArchFlag)
2686         *ArchFlag = "armv7m";
2687       return Triple("thumbv7m-apple-darwin");
2688     case MachO::CPU_SUBTYPE_ARM_V7S:
2689       if (McpuDefault)
2690         *McpuDefault = "cortex-a7";
2691       if (ArchFlag)
2692         *ArchFlag = "armv7s";
2693       return Triple("armv7s-apple-darwin");
2694     default:
2695       return Triple();
2696     }
2697   case MachO::CPU_TYPE_ARM64:
2698     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
2699     case MachO::CPU_SUBTYPE_ARM64_ALL:
2700       if (McpuDefault)
2701         *McpuDefault = "cyclone";
2702       if (ArchFlag)
2703         *ArchFlag = "arm64";
2704       return Triple("arm64-apple-darwin");
2705     case MachO::CPU_SUBTYPE_ARM64E:
2706       if (McpuDefault)
2707         *McpuDefault = "apple-a12";
2708       if (ArchFlag)
2709         *ArchFlag = "arm64e";
2710       return Triple("arm64e-apple-darwin");
2711     default:
2712       return Triple();
2713     }
2714   case MachO::CPU_TYPE_ARM64_32:
2715     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
2716     case MachO::CPU_SUBTYPE_ARM64_32_V8:
2717       if (McpuDefault)
2718         *McpuDefault = "cyclone";
2719       if (ArchFlag)
2720         *ArchFlag = "arm64_32";
2721       return Triple("arm64_32-apple-darwin");
2722     default:
2723       return Triple();
2724     }
2725   case MachO::CPU_TYPE_POWERPC:
2726     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
2727     case MachO::CPU_SUBTYPE_POWERPC_ALL:
2728       if (ArchFlag)
2729         *ArchFlag = "ppc";
2730       return Triple("ppc-apple-darwin");
2731     default:
2732       return Triple();
2733     }
2734   case MachO::CPU_TYPE_POWERPC64:
2735     switch (CPUSubType & ~MachO::CPU_SUBTYPE_MASK) {
2736     case MachO::CPU_SUBTYPE_POWERPC_ALL:
2737       if (ArchFlag)
2738         *ArchFlag = "ppc64";
2739       return Triple("ppc64-apple-darwin");
2740     default:
2741       return Triple();
2742     }
2743   default:
2744     return Triple();
2745   }
2746 }
2747 
getHostArch()2748 Triple MachOObjectFile::getHostArch() {
2749   return Triple(sys::getDefaultTargetTriple());
2750 }
2751 
isValidArch(StringRef ArchFlag)2752 bool MachOObjectFile::isValidArch(StringRef ArchFlag) {
2753   auto validArchs = getValidArchs();
2754   return llvm::is_contained(validArchs, ArchFlag);
2755 }
2756 
getValidArchs()2757 ArrayRef<StringRef> MachOObjectFile::getValidArchs() {
2758   static const std::array<StringRef, 18> ValidArchs = {{
2759       "i386",
2760       "x86_64",
2761       "x86_64h",
2762       "armv4t",
2763       "arm",
2764       "armv5e",
2765       "armv6",
2766       "armv6m",
2767       "armv7",
2768       "armv7em",
2769       "armv7k",
2770       "armv7m",
2771       "armv7s",
2772       "arm64",
2773       "arm64e",
2774       "arm64_32",
2775       "ppc",
2776       "ppc64",
2777   }};
2778 
2779   return ValidArchs;
2780 }
2781 
getArch() const2782 Triple::ArchType MachOObjectFile::getArch() const {
2783   return getArch(getCPUType(*this), getCPUSubType(*this));
2784 }
2785 
getArchTriple(const char ** McpuDefault) const2786 Triple MachOObjectFile::getArchTriple(const char **McpuDefault) const {
2787   return getArchTriple(Header.cputype, Header.cpusubtype, McpuDefault);
2788 }
2789 
section_rel_begin(unsigned Index) const2790 relocation_iterator MachOObjectFile::section_rel_begin(unsigned Index) const {
2791   DataRefImpl DRI;
2792   DRI.d.a = Index;
2793   return section_rel_begin(DRI);
2794 }
2795 
section_rel_end(unsigned Index) const2796 relocation_iterator MachOObjectFile::section_rel_end(unsigned Index) const {
2797   DataRefImpl DRI;
2798   DRI.d.a = Index;
2799   return section_rel_end(DRI);
2800 }
2801 
begin_dices() const2802 dice_iterator MachOObjectFile::begin_dices() const {
2803   DataRefImpl DRI;
2804   if (!DataInCodeLoadCmd)
2805     return dice_iterator(DiceRef(DRI, this));
2806 
2807   MachO::linkedit_data_command DicLC = getDataInCodeLoadCommand();
2808   DRI.p = reinterpret_cast<uintptr_t>(getPtr(*this, DicLC.dataoff));
2809   return dice_iterator(DiceRef(DRI, this));
2810 }
2811 
end_dices() const2812 dice_iterator MachOObjectFile::end_dices() const {
2813   DataRefImpl DRI;
2814   if (!DataInCodeLoadCmd)
2815     return dice_iterator(DiceRef(DRI, this));
2816 
2817   MachO::linkedit_data_command DicLC = getDataInCodeLoadCommand();
2818   unsigned Offset = DicLC.dataoff + DicLC.datasize;
2819   DRI.p = reinterpret_cast<uintptr_t>(getPtr(*this, Offset));
2820   return dice_iterator(DiceRef(DRI, this));
2821 }
2822 
ExportEntry(Error * E,const MachOObjectFile * O,ArrayRef<uint8_t> T)2823 ExportEntry::ExportEntry(Error *E, const MachOObjectFile *O,
2824                          ArrayRef<uint8_t> T) : E(E), O(O), Trie(T) {}
2825 
moveToFirst()2826 void ExportEntry::moveToFirst() {
2827   ErrorAsOutParameter ErrAsOutParam(E);
2828   pushNode(0);
2829   if (*E)
2830     return;
2831   pushDownUntilBottom();
2832 }
2833 
moveToEnd()2834 void ExportEntry::moveToEnd() {
2835   Stack.clear();
2836   Done = true;
2837 }
2838 
operator ==(const ExportEntry & Other) const2839 bool ExportEntry::operator==(const ExportEntry &Other) const {
2840   // Common case, one at end, other iterating from begin.
2841   if (Done || Other.Done)
2842     return (Done == Other.Done);
2843   // Not equal if different stack sizes.
2844   if (Stack.size() != Other.Stack.size())
2845     return false;
2846   // Not equal if different cumulative strings.
2847   if (!CumulativeString.equals(Other.CumulativeString))
2848     return false;
2849   // Equal if all nodes in both stacks match.
2850   for (unsigned i=0; i < Stack.size(); ++i) {
2851     if (Stack[i].Start != Other.Stack[i].Start)
2852       return false;
2853   }
2854   return true;
2855 }
2856 
readULEB128(const uint8_t * & Ptr,const char ** error)2857 uint64_t ExportEntry::readULEB128(const uint8_t *&Ptr, const char **error) {
2858   unsigned Count;
2859   uint64_t Result = decodeULEB128(Ptr, &Count, Trie.end(), error);
2860   Ptr += Count;
2861   if (Ptr > Trie.end())
2862     Ptr = Trie.end();
2863   return Result;
2864 }
2865 
name() const2866 StringRef ExportEntry::name() const {
2867   return CumulativeString;
2868 }
2869 
flags() const2870 uint64_t ExportEntry::flags() const {
2871   return Stack.back().Flags;
2872 }
2873 
address() const2874 uint64_t ExportEntry::address() const {
2875   return Stack.back().Address;
2876 }
2877 
other() const2878 uint64_t ExportEntry::other() const {
2879   return Stack.back().Other;
2880 }
2881 
otherName() const2882 StringRef ExportEntry::otherName() const {
2883   const char* ImportName = Stack.back().ImportName;
2884   if (ImportName)
2885     return StringRef(ImportName);
2886   return StringRef();
2887 }
2888 
nodeOffset() const2889 uint32_t ExportEntry::nodeOffset() const {
2890   return Stack.back().Start - Trie.begin();
2891 }
2892 
NodeState(const uint8_t * Ptr)2893 ExportEntry::NodeState::NodeState(const uint8_t *Ptr)
2894     : Start(Ptr), Current(Ptr) {}
2895 
pushNode(uint64_t offset)2896 void ExportEntry::pushNode(uint64_t offset) {
2897   ErrorAsOutParameter ErrAsOutParam(E);
2898   const uint8_t *Ptr = Trie.begin() + offset;
2899   NodeState State(Ptr);
2900   const char *error;
2901   uint64_t ExportInfoSize = readULEB128(State.Current, &error);
2902   if (error) {
2903     *E = malformedError("export info size " + Twine(error) +
2904                         " in export trie data at node: 0x" +
2905                         Twine::utohexstr(offset));
2906     moveToEnd();
2907     return;
2908   }
2909   State.IsExportNode = (ExportInfoSize != 0);
2910   const uint8_t* Children = State.Current + ExportInfoSize;
2911   if (Children > Trie.end()) {
2912     *E = malformedError(
2913         "export info size: 0x" + Twine::utohexstr(ExportInfoSize) +
2914         " in export trie data at node: 0x" + Twine::utohexstr(offset) +
2915         " too big and extends past end of trie data");
2916     moveToEnd();
2917     return;
2918   }
2919   if (State.IsExportNode) {
2920     const uint8_t *ExportStart = State.Current;
2921     State.Flags = readULEB128(State.Current, &error);
2922     if (error) {
2923       *E = malformedError("flags " + Twine(error) +
2924                           " in export trie data at node: 0x" +
2925                           Twine::utohexstr(offset));
2926       moveToEnd();
2927       return;
2928     }
2929     uint64_t Kind = State.Flags & MachO::EXPORT_SYMBOL_FLAGS_KIND_MASK;
2930     if (State.Flags != 0 &&
2931         (Kind != MachO::EXPORT_SYMBOL_FLAGS_KIND_REGULAR &&
2932          Kind != MachO::EXPORT_SYMBOL_FLAGS_KIND_ABSOLUTE &&
2933          Kind != MachO::EXPORT_SYMBOL_FLAGS_KIND_THREAD_LOCAL)) {
2934       *E = malformedError(
2935           "unsupported exported symbol kind: " + Twine((int)Kind) +
2936           " in flags: 0x" + Twine::utohexstr(State.Flags) +
2937           " in export trie data at node: 0x" + Twine::utohexstr(offset));
2938       moveToEnd();
2939       return;
2940     }
2941     if (State.Flags & MachO::EXPORT_SYMBOL_FLAGS_REEXPORT) {
2942       State.Address = 0;
2943       State.Other = readULEB128(State.Current, &error); // dylib ordinal
2944       if (error) {
2945         *E = malformedError("dylib ordinal of re-export " + Twine(error) +
2946                             " in export trie data at node: 0x" +
2947                             Twine::utohexstr(offset));
2948         moveToEnd();
2949         return;
2950       }
2951       if (O != nullptr) {
2952         if (State.Other > O->getLibraryCount()) {
2953           *E = malformedError(
2954               "bad library ordinal: " + Twine((int)State.Other) + " (max " +
2955               Twine((int)O->getLibraryCount()) +
2956               ") in export trie data at node: 0x" + Twine::utohexstr(offset));
2957           moveToEnd();
2958           return;
2959         }
2960       }
2961       State.ImportName = reinterpret_cast<const char*>(State.Current);
2962       if (*State.ImportName == '\0') {
2963         State.Current++;
2964       } else {
2965         const uint8_t *End = State.Current + 1;
2966         if (End >= Trie.end()) {
2967           *E = malformedError("import name of re-export in export trie data at "
2968                               "node: 0x" +
2969                               Twine::utohexstr(offset) +
2970                               " starts past end of trie data");
2971           moveToEnd();
2972           return;
2973         }
2974         while(*End != '\0' && End < Trie.end())
2975           End++;
2976         if (*End != '\0') {
2977           *E = malformedError("import name of re-export in export trie data at "
2978                               "node: 0x" +
2979                               Twine::utohexstr(offset) +
2980                               " extends past end of trie data");
2981           moveToEnd();
2982           return;
2983         }
2984         State.Current = End + 1;
2985       }
2986     } else {
2987       State.Address = readULEB128(State.Current, &error);
2988       if (error) {
2989         *E = malformedError("address " + Twine(error) +
2990                             " in export trie data at node: 0x" +
2991                             Twine::utohexstr(offset));
2992         moveToEnd();
2993         return;
2994       }
2995       if (State.Flags & MachO::EXPORT_SYMBOL_FLAGS_STUB_AND_RESOLVER) {
2996         State.Other = readULEB128(State.Current, &error);
2997         if (error) {
2998           *E = malformedError("resolver of stub and resolver " + Twine(error) +
2999                               " in export trie data at node: 0x" +
3000                               Twine::utohexstr(offset));
3001           moveToEnd();
3002           return;
3003         }
3004       }
3005     }
3006     if(ExportStart + ExportInfoSize != State.Current) {
3007       *E = malformedError(
3008           "inconsistant export info size: 0x" +
3009           Twine::utohexstr(ExportInfoSize) + " where actual size was: 0x" +
3010           Twine::utohexstr(State.Current - ExportStart) +
3011           " in export trie data at node: 0x" + Twine::utohexstr(offset));
3012       moveToEnd();
3013       return;
3014     }
3015   }
3016   State.ChildCount = *Children;
3017   if (State.ChildCount != 0 && Children + 1 >= Trie.end()) {
3018     *E = malformedError("byte for count of childern in export trie data at "
3019                         "node: 0x" +
3020                         Twine::utohexstr(offset) +
3021                         " extends past end of trie data");
3022     moveToEnd();
3023     return;
3024   }
3025   State.Current = Children + 1;
3026   State.NextChildIndex = 0;
3027   State.ParentStringLength = CumulativeString.size();
3028   Stack.push_back(State);
3029 }
3030 
pushDownUntilBottom()3031 void ExportEntry::pushDownUntilBottom() {
3032   ErrorAsOutParameter ErrAsOutParam(E);
3033   const char *error;
3034   while (Stack.back().NextChildIndex < Stack.back().ChildCount) {
3035     NodeState &Top = Stack.back();
3036     CumulativeString.resize(Top.ParentStringLength);
3037     for (;*Top.Current != 0 && Top.Current < Trie.end(); Top.Current++) {
3038       char C = *Top.Current;
3039       CumulativeString.push_back(C);
3040     }
3041     if (Top.Current >= Trie.end()) {
3042       *E = malformedError("edge sub-string in export trie data at node: 0x" +
3043                           Twine::utohexstr(Top.Start - Trie.begin()) +
3044                           " for child #" + Twine((int)Top.NextChildIndex) +
3045                           " extends past end of trie data");
3046       moveToEnd();
3047       return;
3048     }
3049     Top.Current += 1;
3050     uint64_t childNodeIndex = readULEB128(Top.Current, &error);
3051     if (error) {
3052       *E = malformedError("child node offset " + Twine(error) +
3053                           " in export trie data at node: 0x" +
3054                           Twine::utohexstr(Top.Start - Trie.begin()));
3055       moveToEnd();
3056       return;
3057     }
3058     for (const NodeState &node : nodes()) {
3059       if (node.Start == Trie.begin() + childNodeIndex){
3060         *E = malformedError("loop in childern in export trie data at node: 0x" +
3061                             Twine::utohexstr(Top.Start - Trie.begin()) +
3062                             " back to node: 0x" +
3063                             Twine::utohexstr(childNodeIndex));
3064         moveToEnd();
3065         return;
3066       }
3067     }
3068     Top.NextChildIndex += 1;
3069     pushNode(childNodeIndex);
3070     if (*E)
3071       return;
3072   }
3073   if (!Stack.back().IsExportNode) {
3074     *E = malformedError("node is not an export node in export trie data at "
3075                         "node: 0x" +
3076                         Twine::utohexstr(Stack.back().Start - Trie.begin()));
3077     moveToEnd();
3078     return;
3079   }
3080 }
3081 
3082 // We have a trie data structure and need a way to walk it that is compatible
3083 // with the C++ iterator model. The solution is a non-recursive depth first
3084 // traversal where the iterator contains a stack of parent nodes along with a
3085 // string that is the accumulation of all edge strings along the parent chain
3086 // to this point.
3087 //
3088 // There is one "export" node for each exported symbol.  But because some
3089 // symbols may be a prefix of another symbol (e.g. _dup and _dup2), an export
3090 // node may have child nodes too.
3091 //
3092 // The algorithm for moveNext() is to keep moving down the leftmost unvisited
3093 // child until hitting a node with no children (which is an export node or
3094 // else the trie is malformed). On the way down, each node is pushed on the
3095 // stack ivar.  If there is no more ways down, it pops up one and tries to go
3096 // down a sibling path until a childless node is reached.
moveNext()3097 void ExportEntry::moveNext() {
3098   assert(!Stack.empty() && "ExportEntry::moveNext() with empty node stack");
3099   if (!Stack.back().IsExportNode) {
3100     *E = malformedError("node is not an export node in export trie data at "
3101                         "node: 0x" +
3102                         Twine::utohexstr(Stack.back().Start - Trie.begin()));
3103     moveToEnd();
3104     return;
3105   }
3106 
3107   Stack.pop_back();
3108   while (!Stack.empty()) {
3109     NodeState &Top = Stack.back();
3110     if (Top.NextChildIndex < Top.ChildCount) {
3111       pushDownUntilBottom();
3112       // Now at the next export node.
3113       return;
3114     } else {
3115       if (Top.IsExportNode) {
3116         // This node has no children but is itself an export node.
3117         CumulativeString.resize(Top.ParentStringLength);
3118         return;
3119       }
3120       Stack.pop_back();
3121     }
3122   }
3123   Done = true;
3124 }
3125 
3126 iterator_range<export_iterator>
exports(Error & E,ArrayRef<uint8_t> Trie,const MachOObjectFile * O)3127 MachOObjectFile::exports(Error &E, ArrayRef<uint8_t> Trie,
3128                          const MachOObjectFile *O) {
3129   ExportEntry Start(&E, O, Trie);
3130   if (Trie.empty())
3131     Start.moveToEnd();
3132   else
3133     Start.moveToFirst();
3134 
3135   ExportEntry Finish(&E, O, Trie);
3136   Finish.moveToEnd();
3137 
3138   return make_range(export_iterator(Start), export_iterator(Finish));
3139 }
3140 
exports(Error & Err) const3141 iterator_range<export_iterator> MachOObjectFile::exports(Error &Err) const {
3142   return exports(Err, getDyldInfoExportsTrie(), this);
3143 }
3144 
MachORebaseEntry(Error * E,const MachOObjectFile * O,ArrayRef<uint8_t> Bytes,bool is64Bit)3145 MachORebaseEntry::MachORebaseEntry(Error *E, const MachOObjectFile *O,
3146                                    ArrayRef<uint8_t> Bytes, bool is64Bit)
3147     : E(E), O(O), Opcodes(Bytes), Ptr(Bytes.begin()),
3148       PointerSize(is64Bit ? 8 : 4) {}
3149 
moveToFirst()3150 void MachORebaseEntry::moveToFirst() {
3151   Ptr = Opcodes.begin();
3152   moveNext();
3153 }
3154 
moveToEnd()3155 void MachORebaseEntry::moveToEnd() {
3156   Ptr = Opcodes.end();
3157   RemainingLoopCount = 0;
3158   Done = true;
3159 }
3160 
moveNext()3161 void MachORebaseEntry::moveNext() {
3162   ErrorAsOutParameter ErrAsOutParam(E);
3163   // If in the middle of some loop, move to next rebasing in loop.
3164   SegmentOffset += AdvanceAmount;
3165   if (RemainingLoopCount) {
3166     --RemainingLoopCount;
3167     return;
3168   }
3169   // REBASE_OPCODE_DONE is only used for padding if we are not aligned to
3170   // pointer size. Therefore it is possible to reach the end without ever having
3171   // seen REBASE_OPCODE_DONE.
3172   if (Ptr == Opcodes.end()) {
3173     Done = true;
3174     return;
3175   }
3176   bool More = true;
3177   while (More) {
3178     // Parse next opcode and set up next loop.
3179     const uint8_t *OpcodeStart = Ptr;
3180     uint8_t Byte = *Ptr++;
3181     uint8_t ImmValue = Byte & MachO::REBASE_IMMEDIATE_MASK;
3182     uint8_t Opcode = Byte & MachO::REBASE_OPCODE_MASK;
3183     uint32_t Count, Skip;
3184     const char *error = nullptr;
3185     switch (Opcode) {
3186     case MachO::REBASE_OPCODE_DONE:
3187       More = false;
3188       Done = true;
3189       moveToEnd();
3190       DEBUG_WITH_TYPE("mach-o-rebase", dbgs() << "REBASE_OPCODE_DONE\n");
3191       break;
3192     case MachO::REBASE_OPCODE_SET_TYPE_IMM:
3193       RebaseType = ImmValue;
3194       if (RebaseType > MachO::REBASE_TYPE_TEXT_PCREL32) {
3195         *E = malformedError("for REBASE_OPCODE_SET_TYPE_IMM bad bind type: " +
3196                             Twine((int)RebaseType) + " for opcode at: 0x" +
3197                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3198         moveToEnd();
3199         return;
3200       }
3201       DEBUG_WITH_TYPE(
3202           "mach-o-rebase",
3203           dbgs() << "REBASE_OPCODE_SET_TYPE_IMM: "
3204                  << "RebaseType=" << (int) RebaseType << "\n");
3205       break;
3206     case MachO::REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
3207       SegmentIndex = ImmValue;
3208       SegmentOffset = readULEB128(&error);
3209       if (error) {
3210         *E = malformedError("for REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB " +
3211                             Twine(error) + " for opcode at: 0x" +
3212                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3213         moveToEnd();
3214         return;
3215       }
3216       error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3217                                                PointerSize);
3218       if (error) {
3219         *E = malformedError("for REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB " +
3220                             Twine(error) + " for opcode at: 0x" +
3221                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3222         moveToEnd();
3223         return;
3224       }
3225       DEBUG_WITH_TYPE(
3226           "mach-o-rebase",
3227           dbgs() << "REBASE_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB: "
3228                  << "SegmentIndex=" << SegmentIndex << ", "
3229                  << format("SegmentOffset=0x%06X", SegmentOffset)
3230                  << "\n");
3231       break;
3232     case MachO::REBASE_OPCODE_ADD_ADDR_ULEB:
3233       SegmentOffset += readULEB128(&error);
3234       if (error) {
3235         *E = malformedError("for REBASE_OPCODE_ADD_ADDR_ULEB " + Twine(error) +
3236                             " for opcode at: 0x" +
3237                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3238         moveToEnd();
3239         return;
3240       }
3241       error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3242                                                PointerSize);
3243       if (error) {
3244         *E = malformedError("for REBASE_OPCODE_ADD_ADDR_ULEB " + Twine(error) +
3245                             " for opcode at: 0x" +
3246                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3247         moveToEnd();
3248         return;
3249       }
3250       DEBUG_WITH_TYPE("mach-o-rebase",
3251                       dbgs() << "REBASE_OPCODE_ADD_ADDR_ULEB: "
3252                              << format("SegmentOffset=0x%06X",
3253                                        SegmentOffset) << "\n");
3254       break;
3255     case MachO::REBASE_OPCODE_ADD_ADDR_IMM_SCALED:
3256       SegmentOffset += ImmValue * PointerSize;
3257       error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3258                                                PointerSize);
3259       if (error) {
3260         *E = malformedError("for REBASE_OPCODE_ADD_ADDR_IMM_SCALED " +
3261                             Twine(error) + " for opcode at: 0x" +
3262                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3263         moveToEnd();
3264         return;
3265       }
3266       DEBUG_WITH_TYPE("mach-o-rebase",
3267                       dbgs() << "REBASE_OPCODE_ADD_ADDR_IMM_SCALED: "
3268                              << format("SegmentOffset=0x%06X",
3269                                        SegmentOffset) << "\n");
3270       break;
3271     case MachO::REBASE_OPCODE_DO_REBASE_IMM_TIMES:
3272       AdvanceAmount = PointerSize;
3273       Skip = 0;
3274       Count = ImmValue;
3275       if (ImmValue != 0)
3276         RemainingLoopCount = ImmValue - 1;
3277       else
3278         RemainingLoopCount = 0;
3279       error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3280                                                PointerSize, Count, Skip);
3281       if (error) {
3282         *E = malformedError("for REBASE_OPCODE_DO_REBASE_IMM_TIMES " +
3283                             Twine(error) + " for opcode at: 0x" +
3284                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3285         moveToEnd();
3286         return;
3287       }
3288       DEBUG_WITH_TYPE(
3289           "mach-o-rebase",
3290           dbgs() << "REBASE_OPCODE_DO_REBASE_IMM_TIMES: "
3291                  << format("SegmentOffset=0x%06X", SegmentOffset)
3292                  << ", AdvanceAmount=" << AdvanceAmount
3293                  << ", RemainingLoopCount=" << RemainingLoopCount
3294                  << "\n");
3295       return;
3296     case MachO::REBASE_OPCODE_DO_REBASE_ULEB_TIMES:
3297       AdvanceAmount = PointerSize;
3298       Skip = 0;
3299       Count = readULEB128(&error);
3300       if (error) {
3301         *E = malformedError("for REBASE_OPCODE_DO_REBASE_ULEB_TIMES " +
3302                             Twine(error) + " for opcode at: 0x" +
3303                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3304         moveToEnd();
3305         return;
3306       }
3307       if (Count != 0)
3308         RemainingLoopCount = Count - 1;
3309       else
3310         RemainingLoopCount = 0;
3311       error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3312                                                PointerSize, Count, Skip);
3313       if (error) {
3314         *E = malformedError("for REBASE_OPCODE_DO_REBASE_ULEB_TIMES " +
3315                             Twine(error) + " for opcode at: 0x" +
3316                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3317         moveToEnd();
3318         return;
3319       }
3320       DEBUG_WITH_TYPE(
3321           "mach-o-rebase",
3322           dbgs() << "REBASE_OPCODE_DO_REBASE_ULEB_TIMES: "
3323                  << format("SegmentOffset=0x%06X", SegmentOffset)
3324                  << ", AdvanceAmount=" << AdvanceAmount
3325                  << ", RemainingLoopCount=" << RemainingLoopCount
3326                  << "\n");
3327       return;
3328     case MachO::REBASE_OPCODE_DO_REBASE_ADD_ADDR_ULEB:
3329       Skip = readULEB128(&error);
3330       if (error) {
3331         *E = malformedError("for REBASE_OPCODE_DO_REBASE_ADD_ADDR_ULEB " +
3332                             Twine(error) + " for opcode at: 0x" +
3333                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3334         moveToEnd();
3335         return;
3336       }
3337       AdvanceAmount = Skip + PointerSize;
3338       Count = 1;
3339       RemainingLoopCount = 0;
3340       error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3341                                                PointerSize, Count, Skip);
3342       if (error) {
3343         *E = malformedError("for REBASE_OPCODE_DO_REBASE_ADD_ADDR_ULEB " +
3344                             Twine(error) + " for opcode at: 0x" +
3345                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3346         moveToEnd();
3347         return;
3348       }
3349       DEBUG_WITH_TYPE(
3350           "mach-o-rebase",
3351           dbgs() << "REBASE_OPCODE_DO_REBASE_ADD_ADDR_ULEB: "
3352                  << format("SegmentOffset=0x%06X", SegmentOffset)
3353                  << ", AdvanceAmount=" << AdvanceAmount
3354                  << ", RemainingLoopCount=" << RemainingLoopCount
3355                  << "\n");
3356       return;
3357     case MachO::REBASE_OPCODE_DO_REBASE_ULEB_TIMES_SKIPPING_ULEB:
3358       Count = readULEB128(&error);
3359       if (error) {
3360         *E = malformedError("for REBASE_OPCODE_DO_REBASE_ULEB_TIMES_SKIPPING_"
3361                             "ULEB " +
3362                             Twine(error) + " for opcode at: 0x" +
3363                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3364         moveToEnd();
3365         return;
3366       }
3367       if (Count != 0)
3368         RemainingLoopCount = Count - 1;
3369       else
3370         RemainingLoopCount = 0;
3371       Skip = readULEB128(&error);
3372       if (error) {
3373         *E = malformedError("for REBASE_OPCODE_DO_REBASE_ULEB_TIMES_SKIPPING_"
3374                             "ULEB " +
3375                             Twine(error) + " for opcode at: 0x" +
3376                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3377         moveToEnd();
3378         return;
3379       }
3380       AdvanceAmount = Skip + PointerSize;
3381 
3382       error = O->RebaseEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3383                                                PointerSize, Count, Skip);
3384       if (error) {
3385         *E = malformedError("for REBASE_OPCODE_DO_REBASE_ULEB_TIMES_SKIPPING_"
3386                             "ULEB " +
3387                             Twine(error) + " for opcode at: 0x" +
3388                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3389         moveToEnd();
3390         return;
3391       }
3392       DEBUG_WITH_TYPE(
3393           "mach-o-rebase",
3394           dbgs() << "REBASE_OPCODE_DO_REBASE_ULEB_TIMES_SKIPPING_ULEB: "
3395                  << format("SegmentOffset=0x%06X", SegmentOffset)
3396                  << ", AdvanceAmount=" << AdvanceAmount
3397                  << ", RemainingLoopCount=" << RemainingLoopCount
3398                  << "\n");
3399       return;
3400     default:
3401       *E = malformedError("bad rebase info (bad opcode value 0x" +
3402                           Twine::utohexstr(Opcode) + " for opcode at: 0x" +
3403                           Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3404       moveToEnd();
3405       return;
3406     }
3407   }
3408 }
3409 
readULEB128(const char ** error)3410 uint64_t MachORebaseEntry::readULEB128(const char **error) {
3411   unsigned Count;
3412   uint64_t Result = decodeULEB128(Ptr, &Count, Opcodes.end(), error);
3413   Ptr += Count;
3414   if (Ptr > Opcodes.end())
3415     Ptr = Opcodes.end();
3416   return Result;
3417 }
3418 
segmentIndex() const3419 int32_t MachORebaseEntry::segmentIndex() const { return SegmentIndex; }
3420 
segmentOffset() const3421 uint64_t MachORebaseEntry::segmentOffset() const { return SegmentOffset; }
3422 
typeName() const3423 StringRef MachORebaseEntry::typeName() const {
3424   switch (RebaseType) {
3425   case MachO::REBASE_TYPE_POINTER:
3426     return "pointer";
3427   case MachO::REBASE_TYPE_TEXT_ABSOLUTE32:
3428     return "text abs32";
3429   case MachO::REBASE_TYPE_TEXT_PCREL32:
3430     return "text rel32";
3431   }
3432   return "unknown";
3433 }
3434 
3435 // For use with the SegIndex of a checked Mach-O Rebase entry
3436 // to get the segment name.
segmentName() const3437 StringRef MachORebaseEntry::segmentName() const {
3438   return O->BindRebaseSegmentName(SegmentIndex);
3439 }
3440 
3441 // For use with a SegIndex,SegOffset pair from a checked Mach-O Rebase entry
3442 // to get the section name.
sectionName() const3443 StringRef MachORebaseEntry::sectionName() const {
3444   return O->BindRebaseSectionName(SegmentIndex, SegmentOffset);
3445 }
3446 
3447 // For use with a SegIndex,SegOffset pair from a checked Mach-O Rebase entry
3448 // to get the address.
address() const3449 uint64_t MachORebaseEntry::address() const {
3450   return O->BindRebaseAddress(SegmentIndex, SegmentOffset);
3451 }
3452 
operator ==(const MachORebaseEntry & Other) const3453 bool MachORebaseEntry::operator==(const MachORebaseEntry &Other) const {
3454 #ifdef EXPENSIVE_CHECKS
3455   assert(Opcodes == Other.Opcodes && "compare iterators of different files");
3456 #else
3457   assert(Opcodes.data() == Other.Opcodes.data() && "compare iterators of different files");
3458 #endif
3459   return (Ptr == Other.Ptr) &&
3460          (RemainingLoopCount == Other.RemainingLoopCount) &&
3461          (Done == Other.Done);
3462 }
3463 
3464 iterator_range<rebase_iterator>
rebaseTable(Error & Err,MachOObjectFile * O,ArrayRef<uint8_t> Opcodes,bool is64)3465 MachOObjectFile::rebaseTable(Error &Err, MachOObjectFile *O,
3466                              ArrayRef<uint8_t> Opcodes, bool is64) {
3467   if (O->BindRebaseSectionTable == nullptr)
3468     O->BindRebaseSectionTable = std::make_unique<BindRebaseSegInfo>(O);
3469   MachORebaseEntry Start(&Err, O, Opcodes, is64);
3470   Start.moveToFirst();
3471 
3472   MachORebaseEntry Finish(&Err, O, Opcodes, is64);
3473   Finish.moveToEnd();
3474 
3475   return make_range(rebase_iterator(Start), rebase_iterator(Finish));
3476 }
3477 
rebaseTable(Error & Err)3478 iterator_range<rebase_iterator> MachOObjectFile::rebaseTable(Error &Err) {
3479   return rebaseTable(Err, this, getDyldInfoRebaseOpcodes(), is64Bit());
3480 }
3481 
MachOBindEntry(Error * E,const MachOObjectFile * O,ArrayRef<uint8_t> Bytes,bool is64Bit,Kind BK)3482 MachOBindEntry::MachOBindEntry(Error *E, const MachOObjectFile *O,
3483                                ArrayRef<uint8_t> Bytes, bool is64Bit, Kind BK)
3484     : E(E), O(O), Opcodes(Bytes), Ptr(Bytes.begin()),
3485       PointerSize(is64Bit ? 8 : 4), TableKind(BK) {}
3486 
moveToFirst()3487 void MachOBindEntry::moveToFirst() {
3488   Ptr = Opcodes.begin();
3489   moveNext();
3490 }
3491 
moveToEnd()3492 void MachOBindEntry::moveToEnd() {
3493   Ptr = Opcodes.end();
3494   RemainingLoopCount = 0;
3495   Done = true;
3496 }
3497 
moveNext()3498 void MachOBindEntry::moveNext() {
3499   ErrorAsOutParameter ErrAsOutParam(E);
3500   // If in the middle of some loop, move to next binding in loop.
3501   SegmentOffset += AdvanceAmount;
3502   if (RemainingLoopCount) {
3503     --RemainingLoopCount;
3504     return;
3505   }
3506   // BIND_OPCODE_DONE is only used for padding if we are not aligned to
3507   // pointer size. Therefore it is possible to reach the end without ever having
3508   // seen BIND_OPCODE_DONE.
3509   if (Ptr == Opcodes.end()) {
3510     Done = true;
3511     return;
3512   }
3513   bool More = true;
3514   while (More) {
3515     // Parse next opcode and set up next loop.
3516     const uint8_t *OpcodeStart = Ptr;
3517     uint8_t Byte = *Ptr++;
3518     uint8_t ImmValue = Byte & MachO::BIND_IMMEDIATE_MASK;
3519     uint8_t Opcode = Byte & MachO::BIND_OPCODE_MASK;
3520     int8_t SignExtended;
3521     const uint8_t *SymStart;
3522     uint32_t Count, Skip;
3523     const char *error = nullptr;
3524     switch (Opcode) {
3525     case MachO::BIND_OPCODE_DONE:
3526       if (TableKind == Kind::Lazy) {
3527         // Lazying bindings have a DONE opcode between entries.  Need to ignore
3528         // it to advance to next entry.  But need not if this is last entry.
3529         bool NotLastEntry = false;
3530         for (const uint8_t *P = Ptr; P < Opcodes.end(); ++P) {
3531           if (*P) {
3532             NotLastEntry = true;
3533           }
3534         }
3535         if (NotLastEntry)
3536           break;
3537       }
3538       More = false;
3539       moveToEnd();
3540       DEBUG_WITH_TYPE("mach-o-bind", dbgs() << "BIND_OPCODE_DONE\n");
3541       break;
3542     case MachO::BIND_OPCODE_SET_DYLIB_ORDINAL_IMM:
3543       if (TableKind == Kind::Weak) {
3544         *E = malformedError("BIND_OPCODE_SET_DYLIB_ORDINAL_IMM not allowed in "
3545                             "weak bind table for opcode at: 0x" +
3546                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3547         moveToEnd();
3548         return;
3549       }
3550       Ordinal = ImmValue;
3551       LibraryOrdinalSet = true;
3552       if (ImmValue > O->getLibraryCount()) {
3553         *E = malformedError("for BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB bad "
3554                             "library ordinal: " +
3555                             Twine((int)ImmValue) + " (max " +
3556                             Twine((int)O->getLibraryCount()) +
3557                             ") for opcode at: 0x" +
3558                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3559         moveToEnd();
3560         return;
3561       }
3562       DEBUG_WITH_TYPE(
3563           "mach-o-bind",
3564           dbgs() << "BIND_OPCODE_SET_DYLIB_ORDINAL_IMM: "
3565                  << "Ordinal=" << Ordinal << "\n");
3566       break;
3567     case MachO::BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB:
3568       if (TableKind == Kind::Weak) {
3569         *E = malformedError("BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB not allowed in "
3570                             "weak bind table for opcode at: 0x" +
3571                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3572         moveToEnd();
3573         return;
3574       }
3575       Ordinal = readULEB128(&error);
3576       LibraryOrdinalSet = true;
3577       if (error) {
3578         *E = malformedError("for BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB " +
3579                             Twine(error) + " for opcode at: 0x" +
3580                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3581         moveToEnd();
3582         return;
3583       }
3584       if (Ordinal > (int)O->getLibraryCount()) {
3585         *E = malformedError("for BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB bad "
3586                             "library ordinal: " +
3587                             Twine((int)Ordinal) + " (max " +
3588                             Twine((int)O->getLibraryCount()) +
3589                             ") for opcode at: 0x" +
3590                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3591         moveToEnd();
3592         return;
3593       }
3594       DEBUG_WITH_TYPE(
3595           "mach-o-bind",
3596           dbgs() << "BIND_OPCODE_SET_DYLIB_ORDINAL_ULEB: "
3597                  << "Ordinal=" << Ordinal << "\n");
3598       break;
3599     case MachO::BIND_OPCODE_SET_DYLIB_SPECIAL_IMM:
3600       if (TableKind == Kind::Weak) {
3601         *E = malformedError("BIND_OPCODE_SET_DYLIB_SPECIAL_IMM not allowed in "
3602                             "weak bind table for opcode at: 0x" +
3603                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3604         moveToEnd();
3605         return;
3606       }
3607       if (ImmValue) {
3608         SignExtended = MachO::BIND_OPCODE_MASK | ImmValue;
3609         Ordinal = SignExtended;
3610         if (Ordinal < MachO::BIND_SPECIAL_DYLIB_FLAT_LOOKUP) {
3611           *E = malformedError("for BIND_OPCODE_SET_DYLIB_SPECIAL_IMM unknown "
3612                               "special ordinal: " +
3613                               Twine((int)Ordinal) + " for opcode at: 0x" +
3614                               Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3615           moveToEnd();
3616           return;
3617         }
3618       } else
3619         Ordinal = 0;
3620       LibraryOrdinalSet = true;
3621       DEBUG_WITH_TYPE(
3622           "mach-o-bind",
3623           dbgs() << "BIND_OPCODE_SET_DYLIB_SPECIAL_IMM: "
3624                  << "Ordinal=" << Ordinal << "\n");
3625       break;
3626     case MachO::BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM:
3627       Flags = ImmValue;
3628       SymStart = Ptr;
3629       while (*Ptr && (Ptr < Opcodes.end())) {
3630         ++Ptr;
3631       }
3632       if (Ptr == Opcodes.end()) {
3633         *E = malformedError(
3634             "for BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM "
3635             "symbol name extends past opcodes for opcode at: 0x" +
3636             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3637         moveToEnd();
3638         return;
3639       }
3640       SymbolName = StringRef(reinterpret_cast<const char*>(SymStart),
3641                              Ptr-SymStart);
3642       ++Ptr;
3643       DEBUG_WITH_TYPE(
3644           "mach-o-bind",
3645           dbgs() << "BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM: "
3646                  << "SymbolName=" << SymbolName << "\n");
3647       if (TableKind == Kind::Weak) {
3648         if (ImmValue & MachO::BIND_SYMBOL_FLAGS_NON_WEAK_DEFINITION)
3649           return;
3650       }
3651       break;
3652     case MachO::BIND_OPCODE_SET_TYPE_IMM:
3653       BindType = ImmValue;
3654       if (ImmValue > MachO::BIND_TYPE_TEXT_PCREL32) {
3655         *E = malformedError("for BIND_OPCODE_SET_TYPE_IMM bad bind type: " +
3656                             Twine((int)ImmValue) + " for opcode at: 0x" +
3657                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3658         moveToEnd();
3659         return;
3660       }
3661       DEBUG_WITH_TYPE(
3662           "mach-o-bind",
3663           dbgs() << "BIND_OPCODE_SET_TYPE_IMM: "
3664                  << "BindType=" << (int)BindType << "\n");
3665       break;
3666     case MachO::BIND_OPCODE_SET_ADDEND_SLEB:
3667       Addend = readSLEB128(&error);
3668       if (error) {
3669         *E = malformedError("for BIND_OPCODE_SET_ADDEND_SLEB " + Twine(error) +
3670                             " for opcode at: 0x" +
3671                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3672         moveToEnd();
3673         return;
3674       }
3675       DEBUG_WITH_TYPE(
3676           "mach-o-bind",
3677           dbgs() << "BIND_OPCODE_SET_ADDEND_SLEB: "
3678                  << "Addend=" << Addend << "\n");
3679       break;
3680     case MachO::BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB:
3681       SegmentIndex = ImmValue;
3682       SegmentOffset = readULEB128(&error);
3683       if (error) {
3684         *E = malformedError("for BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB " +
3685                             Twine(error) + " for opcode at: 0x" +
3686                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3687         moveToEnd();
3688         return;
3689       }
3690       error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3691                                              PointerSize);
3692       if (error) {
3693         *E = malformedError("for BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB " +
3694                             Twine(error) + " for opcode at: 0x" +
3695                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3696         moveToEnd();
3697         return;
3698       }
3699       DEBUG_WITH_TYPE(
3700           "mach-o-bind",
3701           dbgs() << "BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB: "
3702                  << "SegmentIndex=" << SegmentIndex << ", "
3703                  << format("SegmentOffset=0x%06X", SegmentOffset)
3704                  << "\n");
3705       break;
3706     case MachO::BIND_OPCODE_ADD_ADDR_ULEB:
3707       SegmentOffset += readULEB128(&error);
3708       if (error) {
3709         *E = malformedError("for BIND_OPCODE_ADD_ADDR_ULEB " + Twine(error) +
3710                             " for opcode at: 0x" +
3711                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3712         moveToEnd();
3713         return;
3714       }
3715       error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3716                                              PointerSize);
3717       if (error) {
3718         *E = malformedError("for BIND_OPCODE_ADD_ADDR_ULEB " + Twine(error) +
3719                             " for opcode at: 0x" +
3720                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3721         moveToEnd();
3722         return;
3723       }
3724       DEBUG_WITH_TYPE("mach-o-bind",
3725                       dbgs() << "BIND_OPCODE_ADD_ADDR_ULEB: "
3726                              << format("SegmentOffset=0x%06X",
3727                                        SegmentOffset) << "\n");
3728       break;
3729     case MachO::BIND_OPCODE_DO_BIND:
3730       AdvanceAmount = PointerSize;
3731       RemainingLoopCount = 0;
3732       error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3733                                              PointerSize);
3734       if (error) {
3735         *E = malformedError("for BIND_OPCODE_DO_BIND " + Twine(error) +
3736                             " for opcode at: 0x" +
3737                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3738         moveToEnd();
3739         return;
3740       }
3741       if (SymbolName == StringRef()) {
3742         *E = malformedError(
3743             "for BIND_OPCODE_DO_BIND missing preceding "
3744             "BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM for opcode at: 0x" +
3745             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3746         moveToEnd();
3747         return;
3748       }
3749       if (!LibraryOrdinalSet && TableKind != Kind::Weak) {
3750         *E =
3751             malformedError("for BIND_OPCODE_DO_BIND missing preceding "
3752                            "BIND_OPCODE_SET_DYLIB_ORDINAL_* for opcode at: 0x" +
3753                            Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3754         moveToEnd();
3755         return;
3756       }
3757       DEBUG_WITH_TYPE("mach-o-bind",
3758                       dbgs() << "BIND_OPCODE_DO_BIND: "
3759                              << format("SegmentOffset=0x%06X",
3760                                        SegmentOffset) << "\n");
3761       return;
3762      case MachO::BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB:
3763       if (TableKind == Kind::Lazy) {
3764         *E = malformedError("BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB not allowed in "
3765                             "lazy bind table for opcode at: 0x" +
3766                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3767         moveToEnd();
3768         return;
3769       }
3770       error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3771                                              PointerSize);
3772       if (error) {
3773         *E = malformedError("for BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB " +
3774                             Twine(error) + " for opcode at: 0x" +
3775                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3776         moveToEnd();
3777         return;
3778       }
3779       if (SymbolName == StringRef()) {
3780         *E = malformedError(
3781             "for BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB missing "
3782             "preceding BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM for opcode "
3783             "at: 0x" +
3784             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3785         moveToEnd();
3786         return;
3787       }
3788       if (!LibraryOrdinalSet && TableKind != Kind::Weak) {
3789         *E = malformedError(
3790             "for BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB missing "
3791             "preceding BIND_OPCODE_SET_DYLIB_ORDINAL_* for opcode at: 0x" +
3792             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3793         moveToEnd();
3794         return;
3795       }
3796       AdvanceAmount = readULEB128(&error) + PointerSize;
3797       if (error) {
3798         *E = malformedError("for BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB " +
3799                             Twine(error) + " for opcode at: 0x" +
3800                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3801         moveToEnd();
3802         return;
3803       }
3804       // Note, this is not really an error until the next bind but make no sense
3805       // for a BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB to not be followed by another
3806       // bind operation.
3807       error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset +
3808                                             AdvanceAmount, PointerSize);
3809       if (error) {
3810         *E = malformedError("for BIND_OPCODE_ADD_ADDR_ULEB (after adding "
3811                             "ULEB) " +
3812                             Twine(error) + " for opcode at: 0x" +
3813                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3814         moveToEnd();
3815         return;
3816       }
3817       RemainingLoopCount = 0;
3818       DEBUG_WITH_TYPE(
3819           "mach-o-bind",
3820           dbgs() << "BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB: "
3821                  << format("SegmentOffset=0x%06X", SegmentOffset)
3822                  << ", AdvanceAmount=" << AdvanceAmount
3823                  << ", RemainingLoopCount=" << RemainingLoopCount
3824                  << "\n");
3825       return;
3826     case MachO::BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED:
3827       if (TableKind == Kind::Lazy) {
3828         *E = malformedError("BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED not "
3829                             "allowed in lazy bind table for opcode at: 0x" +
3830                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3831         moveToEnd();
3832         return;
3833       }
3834       if (SymbolName == StringRef()) {
3835         *E = malformedError(
3836             "for BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED "
3837             "missing preceding BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM for "
3838             "opcode at: 0x" +
3839             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3840         moveToEnd();
3841         return;
3842       }
3843       if (!LibraryOrdinalSet && TableKind != Kind::Weak) {
3844         *E = malformedError(
3845             "for BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED "
3846             "missing preceding BIND_OPCODE_SET_DYLIB_ORDINAL_* for opcode "
3847             "at: 0x" +
3848             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3849         moveToEnd();
3850         return;
3851       }
3852       AdvanceAmount = ImmValue * PointerSize + PointerSize;
3853       RemainingLoopCount = 0;
3854       error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset +
3855                                              AdvanceAmount, PointerSize);
3856       if (error) {
3857         *E = malformedError("for BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED " +
3858                             Twine(error) + " for opcode at: 0x" +
3859                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3860         moveToEnd();
3861         return;
3862       }
3863       DEBUG_WITH_TYPE("mach-o-bind",
3864                       dbgs()
3865                       << "BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED: "
3866                       << format("SegmentOffset=0x%06X", SegmentOffset) << "\n");
3867       return;
3868     case MachO::BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB:
3869       if (TableKind == Kind::Lazy) {
3870         *E = malformedError("BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB not "
3871                             "allowed in lazy bind table for opcode at: 0x" +
3872                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3873         moveToEnd();
3874         return;
3875       }
3876       Count = readULEB128(&error);
3877       if (Count != 0)
3878         RemainingLoopCount = Count - 1;
3879       else
3880         RemainingLoopCount = 0;
3881       if (error) {
3882         *E = malformedError("for BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB "
3883                             " (count value) " +
3884                             Twine(error) + " for opcode at: 0x" +
3885                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3886         moveToEnd();
3887         return;
3888       }
3889       Skip = readULEB128(&error);
3890       AdvanceAmount = Skip + PointerSize;
3891       if (error) {
3892         *E = malformedError("for BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB "
3893                             " (skip value) " +
3894                             Twine(error) + " for opcode at: 0x" +
3895                             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3896         moveToEnd();
3897         return;
3898       }
3899       if (SymbolName == StringRef()) {
3900         *E = malformedError(
3901             "for BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB "
3902             "missing preceding BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM for "
3903             "opcode at: 0x" +
3904             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3905         moveToEnd();
3906         return;
3907       }
3908       if (!LibraryOrdinalSet && TableKind != Kind::Weak) {
3909         *E = malformedError(
3910             "for BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB "
3911             "missing preceding BIND_OPCODE_SET_DYLIB_ORDINAL_* for opcode "
3912             "at: 0x" +
3913             Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3914         moveToEnd();
3915         return;
3916       }
3917       error = O->BindEntryCheckSegAndOffsets(SegmentIndex, SegmentOffset,
3918                                              PointerSize, Count, Skip);
3919       if (error) {
3920         *E =
3921             malformedError("for BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB " +
3922                            Twine(error) + " for opcode at: 0x" +
3923                            Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3924         moveToEnd();
3925         return;
3926       }
3927       DEBUG_WITH_TYPE(
3928           "mach-o-bind",
3929           dbgs() << "BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB: "
3930                  << format("SegmentOffset=0x%06X", SegmentOffset)
3931                  << ", AdvanceAmount=" << AdvanceAmount
3932                  << ", RemainingLoopCount=" << RemainingLoopCount
3933                  << "\n");
3934       return;
3935     default:
3936       *E = malformedError("bad bind info (bad opcode value 0x" +
3937                           Twine::utohexstr(Opcode) + " for opcode at: 0x" +
3938                           Twine::utohexstr(OpcodeStart - Opcodes.begin()));
3939       moveToEnd();
3940       return;
3941     }
3942   }
3943 }
3944 
readULEB128(const char ** error)3945 uint64_t MachOBindEntry::readULEB128(const char **error) {
3946   unsigned Count;
3947   uint64_t Result = decodeULEB128(Ptr, &Count, Opcodes.end(), error);
3948   Ptr += Count;
3949   if (Ptr > Opcodes.end())
3950     Ptr = Opcodes.end();
3951   return Result;
3952 }
3953 
readSLEB128(const char ** error)3954 int64_t MachOBindEntry::readSLEB128(const char **error) {
3955   unsigned Count;
3956   int64_t Result = decodeSLEB128(Ptr, &Count, Opcodes.end(), error);
3957   Ptr += Count;
3958   if (Ptr > Opcodes.end())
3959     Ptr = Opcodes.end();
3960   return Result;
3961 }
3962 
segmentIndex() const3963 int32_t MachOBindEntry::segmentIndex() const { return SegmentIndex; }
3964 
segmentOffset() const3965 uint64_t MachOBindEntry::segmentOffset() const { return SegmentOffset; }
3966 
typeName() const3967 StringRef MachOBindEntry::typeName() const {
3968   switch (BindType) {
3969   case MachO::BIND_TYPE_POINTER:
3970     return "pointer";
3971   case MachO::BIND_TYPE_TEXT_ABSOLUTE32:
3972     return "text abs32";
3973   case MachO::BIND_TYPE_TEXT_PCREL32:
3974     return "text rel32";
3975   }
3976   return "unknown";
3977 }
3978 
symbolName() const3979 StringRef MachOBindEntry::symbolName() const { return SymbolName; }
3980 
addend() const3981 int64_t MachOBindEntry::addend() const { return Addend; }
3982 
flags() const3983 uint32_t MachOBindEntry::flags() const { return Flags; }
3984 
ordinal() const3985 int MachOBindEntry::ordinal() const { return Ordinal; }
3986 
3987 // For use with the SegIndex of a checked Mach-O Bind entry
3988 // to get the segment name.
segmentName() const3989 StringRef MachOBindEntry::segmentName() const {
3990   return O->BindRebaseSegmentName(SegmentIndex);
3991 }
3992 
3993 // For use with a SegIndex,SegOffset pair from a checked Mach-O Bind entry
3994 // to get the section name.
sectionName() const3995 StringRef MachOBindEntry::sectionName() const {
3996   return O->BindRebaseSectionName(SegmentIndex, SegmentOffset);
3997 }
3998 
3999 // For use with a SegIndex,SegOffset pair from a checked Mach-O Bind entry
4000 // to get the address.
address() const4001 uint64_t MachOBindEntry::address() const {
4002   return O->BindRebaseAddress(SegmentIndex, SegmentOffset);
4003 }
4004 
operator ==(const MachOBindEntry & Other) const4005 bool MachOBindEntry::operator==(const MachOBindEntry &Other) const {
4006 #ifdef EXPENSIVE_CHECKS
4007   assert(Opcodes == Other.Opcodes && "compare iterators of different files");
4008 #else
4009   assert(Opcodes.data() == Other.Opcodes.data() && "compare iterators of different files");
4010 #endif
4011   return (Ptr == Other.Ptr) &&
4012          (RemainingLoopCount == Other.RemainingLoopCount) &&
4013          (Done == Other.Done);
4014 }
4015 
4016 // Build table of sections so SegIndex/SegOffset pairs can be translated.
BindRebaseSegInfo(const object::MachOObjectFile * Obj)4017 BindRebaseSegInfo::BindRebaseSegInfo(const object::MachOObjectFile *Obj) {
4018   uint32_t CurSegIndex = Obj->hasPageZeroSegment() ? 1 : 0;
4019   StringRef CurSegName;
4020   uint64_t CurSegAddress;
4021   for (const SectionRef &Section : Obj->sections()) {
4022     SectionInfo Info;
4023     Expected<StringRef> NameOrErr = Section.getName();
4024     if (!NameOrErr)
4025       consumeError(NameOrErr.takeError());
4026     else
4027       Info.SectionName = *NameOrErr;
4028     Info.Address = Section.getAddress();
4029     Info.Size = Section.getSize();
4030     Info.SegmentName =
4031         Obj->getSectionFinalSegmentName(Section.getRawDataRefImpl());
4032     if (!Info.SegmentName.equals(CurSegName)) {
4033       ++CurSegIndex;
4034       CurSegName = Info.SegmentName;
4035       CurSegAddress = Info.Address;
4036     }
4037     Info.SegmentIndex = CurSegIndex - 1;
4038     Info.OffsetInSegment = Info.Address - CurSegAddress;
4039     Info.SegmentStartAddress = CurSegAddress;
4040     Sections.push_back(Info);
4041   }
4042   MaxSegIndex = CurSegIndex;
4043 }
4044 
4045 // For use with a SegIndex, SegOffset, and PointerSize triple in
4046 // MachOBindEntry::moveNext() to validate a MachOBindEntry or MachORebaseEntry.
4047 //
4048 // Given a SegIndex, SegOffset, and PointerSize, verify a valid section exists
4049 // that fully contains a pointer at that location. Multiple fixups in a bind
4050 // (such as with the BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB opcode) can
4051 // be tested via the Count and Skip parameters.
checkSegAndOffsets(int32_t SegIndex,uint64_t SegOffset,uint8_t PointerSize,uint32_t Count,uint32_t Skip)4052 const char * BindRebaseSegInfo::checkSegAndOffsets(int32_t SegIndex,
4053                                                    uint64_t SegOffset,
4054                                                    uint8_t PointerSize,
4055                                                    uint32_t Count,
4056                                                    uint32_t Skip) {
4057   if (SegIndex == -1)
4058     return "missing preceding *_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB";
4059   if (SegIndex >= MaxSegIndex)
4060     return "bad segIndex (too large)";
4061   for (uint32_t i = 0; i < Count; ++i) {
4062     uint32_t Start = SegOffset + i * (PointerSize + Skip);
4063     uint32_t End = Start + PointerSize;
4064     bool Found = false;
4065     for (const SectionInfo &SI : Sections) {
4066       if (SI.SegmentIndex != SegIndex)
4067         continue;
4068       if ((SI.OffsetInSegment<=Start) && (Start<(SI.OffsetInSegment+SI.Size))) {
4069         if (End <= SI.OffsetInSegment + SI.Size) {
4070           Found = true;
4071           break;
4072         }
4073         else
4074           return "bad offset, extends beyond section boundary";
4075       }
4076     }
4077     if (!Found)
4078       return "bad offset, not in section";
4079   }
4080   return nullptr;
4081 }
4082 
4083 // For use with the SegIndex of a checked Mach-O Bind or Rebase entry
4084 // to get the segment name.
segmentName(int32_t SegIndex)4085 StringRef BindRebaseSegInfo::segmentName(int32_t SegIndex) {
4086   for (const SectionInfo &SI : Sections) {
4087     if (SI.SegmentIndex == SegIndex)
4088       return SI.SegmentName;
4089   }
4090   llvm_unreachable("invalid SegIndex");
4091 }
4092 
4093 // For use with a SegIndex,SegOffset pair from a checked Mach-O Bind or Rebase
4094 // to get the SectionInfo.
findSection(int32_t SegIndex,uint64_t SegOffset)4095 const BindRebaseSegInfo::SectionInfo &BindRebaseSegInfo::findSection(
4096                                      int32_t SegIndex, uint64_t SegOffset) {
4097   for (const SectionInfo &SI : Sections) {
4098     if (SI.SegmentIndex != SegIndex)
4099       continue;
4100     if (SI.OffsetInSegment > SegOffset)
4101       continue;
4102     if (SegOffset >= (SI.OffsetInSegment + SI.Size))
4103       continue;
4104     return SI;
4105   }
4106   llvm_unreachable("SegIndex and SegOffset not in any section");
4107 }
4108 
4109 // For use with a SegIndex,SegOffset pair from a checked Mach-O Bind or Rebase
4110 // entry to get the section name.
sectionName(int32_t SegIndex,uint64_t SegOffset)4111 StringRef BindRebaseSegInfo::sectionName(int32_t SegIndex,
4112                                          uint64_t SegOffset) {
4113   return findSection(SegIndex, SegOffset).SectionName;
4114 }
4115 
4116 // For use with a SegIndex,SegOffset pair from a checked Mach-O Bind or Rebase
4117 // entry to get the address.
address(uint32_t SegIndex,uint64_t OffsetInSeg)4118 uint64_t BindRebaseSegInfo::address(uint32_t SegIndex, uint64_t OffsetInSeg) {
4119   const SectionInfo &SI = findSection(SegIndex, OffsetInSeg);
4120   return SI.SegmentStartAddress + OffsetInSeg;
4121 }
4122 
4123 iterator_range<bind_iterator>
bindTable(Error & Err,MachOObjectFile * O,ArrayRef<uint8_t> Opcodes,bool is64,MachOBindEntry::Kind BKind)4124 MachOObjectFile::bindTable(Error &Err, MachOObjectFile *O,
4125                            ArrayRef<uint8_t> Opcodes, bool is64,
4126                            MachOBindEntry::Kind BKind) {
4127   if (O->BindRebaseSectionTable == nullptr)
4128     O->BindRebaseSectionTable = std::make_unique<BindRebaseSegInfo>(O);
4129   MachOBindEntry Start(&Err, O, Opcodes, is64, BKind);
4130   Start.moveToFirst();
4131 
4132   MachOBindEntry Finish(&Err, O, Opcodes, is64, BKind);
4133   Finish.moveToEnd();
4134 
4135   return make_range(bind_iterator(Start), bind_iterator(Finish));
4136 }
4137 
bindTable(Error & Err)4138 iterator_range<bind_iterator> MachOObjectFile::bindTable(Error &Err) {
4139   return bindTable(Err, this, getDyldInfoBindOpcodes(), is64Bit(),
4140                    MachOBindEntry::Kind::Regular);
4141 }
4142 
lazyBindTable(Error & Err)4143 iterator_range<bind_iterator> MachOObjectFile::lazyBindTable(Error &Err) {
4144   return bindTable(Err, this, getDyldInfoLazyBindOpcodes(), is64Bit(),
4145                    MachOBindEntry::Kind::Lazy);
4146 }
4147 
weakBindTable(Error & Err)4148 iterator_range<bind_iterator> MachOObjectFile::weakBindTable(Error &Err) {
4149   return bindTable(Err, this, getDyldInfoWeakBindOpcodes(), is64Bit(),
4150                    MachOBindEntry::Kind::Weak);
4151 }
4152 
4153 MachOObjectFile::load_command_iterator
begin_load_commands() const4154 MachOObjectFile::begin_load_commands() const {
4155   return LoadCommands.begin();
4156 }
4157 
4158 MachOObjectFile::load_command_iterator
end_load_commands() const4159 MachOObjectFile::end_load_commands() const {
4160   return LoadCommands.end();
4161 }
4162 
4163 iterator_range<MachOObjectFile::load_command_iterator>
load_commands() const4164 MachOObjectFile::load_commands() const {
4165   return make_range(begin_load_commands(), end_load_commands());
4166 }
4167 
4168 StringRef
getSectionFinalSegmentName(DataRefImpl Sec) const4169 MachOObjectFile::getSectionFinalSegmentName(DataRefImpl Sec) const {
4170   ArrayRef<char> Raw = getSectionRawFinalSegmentName(Sec);
4171   return parseSegmentOrSectionName(Raw.data());
4172 }
4173 
4174 ArrayRef<char>
getSectionRawName(DataRefImpl Sec) const4175 MachOObjectFile::getSectionRawName(DataRefImpl Sec) const {
4176   assert(Sec.d.a < Sections.size() && "Should have detected this earlier");
4177   const section_base *Base =
4178     reinterpret_cast<const section_base *>(Sections[Sec.d.a]);
4179   return makeArrayRef(Base->sectname);
4180 }
4181 
4182 ArrayRef<char>
getSectionRawFinalSegmentName(DataRefImpl Sec) const4183 MachOObjectFile::getSectionRawFinalSegmentName(DataRefImpl Sec) const {
4184   assert(Sec.d.a < Sections.size() && "Should have detected this earlier");
4185   const section_base *Base =
4186     reinterpret_cast<const section_base *>(Sections[Sec.d.a]);
4187   return makeArrayRef(Base->segname);
4188 }
4189 
4190 bool
isRelocationScattered(const MachO::any_relocation_info & RE) const4191 MachOObjectFile::isRelocationScattered(const MachO::any_relocation_info &RE)
4192   const {
4193   if (getCPUType(*this) == MachO::CPU_TYPE_X86_64)
4194     return false;
4195   return getPlainRelocationAddress(RE) & MachO::R_SCATTERED;
4196 }
4197 
getPlainRelocationSymbolNum(const MachO::any_relocation_info & RE) const4198 unsigned MachOObjectFile::getPlainRelocationSymbolNum(
4199     const MachO::any_relocation_info &RE) const {
4200   if (isLittleEndian())
4201     return RE.r_word1 & 0xffffff;
4202   return RE.r_word1 >> 8;
4203 }
4204 
getPlainRelocationExternal(const MachO::any_relocation_info & RE) const4205 bool MachOObjectFile::getPlainRelocationExternal(
4206     const MachO::any_relocation_info &RE) const {
4207   if (isLittleEndian())
4208     return (RE.r_word1 >> 27) & 1;
4209   return (RE.r_word1 >> 4) & 1;
4210 }
4211 
getScatteredRelocationScattered(const MachO::any_relocation_info & RE) const4212 bool MachOObjectFile::getScatteredRelocationScattered(
4213     const MachO::any_relocation_info &RE) const {
4214   return RE.r_word0 >> 31;
4215 }
4216 
getScatteredRelocationValue(const MachO::any_relocation_info & RE) const4217 uint32_t MachOObjectFile::getScatteredRelocationValue(
4218     const MachO::any_relocation_info &RE) const {
4219   return RE.r_word1;
4220 }
4221 
getScatteredRelocationType(const MachO::any_relocation_info & RE) const4222 uint32_t MachOObjectFile::getScatteredRelocationType(
4223     const MachO::any_relocation_info &RE) const {
4224   return (RE.r_word0 >> 24) & 0xf;
4225 }
4226 
getAnyRelocationAddress(const MachO::any_relocation_info & RE) const4227 unsigned MachOObjectFile::getAnyRelocationAddress(
4228     const MachO::any_relocation_info &RE) const {
4229   if (isRelocationScattered(RE))
4230     return getScatteredRelocationAddress(RE);
4231   return getPlainRelocationAddress(RE);
4232 }
4233 
getAnyRelocationPCRel(const MachO::any_relocation_info & RE) const4234 unsigned MachOObjectFile::getAnyRelocationPCRel(
4235     const MachO::any_relocation_info &RE) const {
4236   if (isRelocationScattered(RE))
4237     return getScatteredRelocationPCRel(RE);
4238   return getPlainRelocationPCRel(*this, RE);
4239 }
4240 
getAnyRelocationLength(const MachO::any_relocation_info & RE) const4241 unsigned MachOObjectFile::getAnyRelocationLength(
4242     const MachO::any_relocation_info &RE) const {
4243   if (isRelocationScattered(RE))
4244     return getScatteredRelocationLength(RE);
4245   return getPlainRelocationLength(*this, RE);
4246 }
4247 
4248 unsigned
getAnyRelocationType(const MachO::any_relocation_info & RE) const4249 MachOObjectFile::getAnyRelocationType(
4250                                    const MachO::any_relocation_info &RE) const {
4251   if (isRelocationScattered(RE))
4252     return getScatteredRelocationType(RE);
4253   return getPlainRelocationType(*this, RE);
4254 }
4255 
4256 SectionRef
getAnyRelocationSection(const MachO::any_relocation_info & RE) const4257 MachOObjectFile::getAnyRelocationSection(
4258                                    const MachO::any_relocation_info &RE) const {
4259   if (isRelocationScattered(RE) || getPlainRelocationExternal(RE))
4260     return *section_end();
4261   unsigned SecNum = getPlainRelocationSymbolNum(RE);
4262   if (SecNum == MachO::R_ABS || SecNum > Sections.size())
4263     return *section_end();
4264   DataRefImpl DRI;
4265   DRI.d.a = SecNum - 1;
4266   return SectionRef(DRI, this);
4267 }
4268 
getSection(DataRefImpl DRI) const4269 MachO::section MachOObjectFile::getSection(DataRefImpl DRI) const {
4270   assert(DRI.d.a < Sections.size() && "Should have detected this earlier");
4271   return getStruct<MachO::section>(*this, Sections[DRI.d.a]);
4272 }
4273 
getSection64(DataRefImpl DRI) const4274 MachO::section_64 MachOObjectFile::getSection64(DataRefImpl DRI) const {
4275   assert(DRI.d.a < Sections.size() && "Should have detected this earlier");
4276   return getStruct<MachO::section_64>(*this, Sections[DRI.d.a]);
4277 }
4278 
getSection(const LoadCommandInfo & L,unsigned Index) const4279 MachO::section MachOObjectFile::getSection(const LoadCommandInfo &L,
4280                                            unsigned Index) const {
4281   const char *Sec = getSectionPtr(*this, L, Index);
4282   return getStruct<MachO::section>(*this, Sec);
4283 }
4284 
getSection64(const LoadCommandInfo & L,unsigned Index) const4285 MachO::section_64 MachOObjectFile::getSection64(const LoadCommandInfo &L,
4286                                                 unsigned Index) const {
4287   const char *Sec = getSectionPtr(*this, L, Index);
4288   return getStruct<MachO::section_64>(*this, Sec);
4289 }
4290 
4291 MachO::nlist
getSymbolTableEntry(DataRefImpl DRI) const4292 MachOObjectFile::getSymbolTableEntry(DataRefImpl DRI) const {
4293   const char *P = reinterpret_cast<const char *>(DRI.p);
4294   return getStruct<MachO::nlist>(*this, P);
4295 }
4296 
4297 MachO::nlist_64
getSymbol64TableEntry(DataRefImpl DRI) const4298 MachOObjectFile::getSymbol64TableEntry(DataRefImpl DRI) const {
4299   const char *P = reinterpret_cast<const char *>(DRI.p);
4300   return getStruct<MachO::nlist_64>(*this, P);
4301 }
4302 
4303 MachO::linkedit_data_command
getLinkeditDataLoadCommand(const LoadCommandInfo & L) const4304 MachOObjectFile::getLinkeditDataLoadCommand(const LoadCommandInfo &L) const {
4305   return getStruct<MachO::linkedit_data_command>(*this, L.Ptr);
4306 }
4307 
4308 MachO::segment_command
getSegmentLoadCommand(const LoadCommandInfo & L) const4309 MachOObjectFile::getSegmentLoadCommand(const LoadCommandInfo &L) const {
4310   return getStruct<MachO::segment_command>(*this, L.Ptr);
4311 }
4312 
4313 MachO::segment_command_64
getSegment64LoadCommand(const LoadCommandInfo & L) const4314 MachOObjectFile::getSegment64LoadCommand(const LoadCommandInfo &L) const {
4315   return getStruct<MachO::segment_command_64>(*this, L.Ptr);
4316 }
4317 
4318 MachO::linker_option_command
getLinkerOptionLoadCommand(const LoadCommandInfo & L) const4319 MachOObjectFile::getLinkerOptionLoadCommand(const LoadCommandInfo &L) const {
4320   return getStruct<MachO::linker_option_command>(*this, L.Ptr);
4321 }
4322 
4323 MachO::version_min_command
getVersionMinLoadCommand(const LoadCommandInfo & L) const4324 MachOObjectFile::getVersionMinLoadCommand(const LoadCommandInfo &L) const {
4325   return getStruct<MachO::version_min_command>(*this, L.Ptr);
4326 }
4327 
4328 MachO::note_command
getNoteLoadCommand(const LoadCommandInfo & L) const4329 MachOObjectFile::getNoteLoadCommand(const LoadCommandInfo &L) const {
4330   return getStruct<MachO::note_command>(*this, L.Ptr);
4331 }
4332 
4333 MachO::build_version_command
getBuildVersionLoadCommand(const LoadCommandInfo & L) const4334 MachOObjectFile::getBuildVersionLoadCommand(const LoadCommandInfo &L) const {
4335   return getStruct<MachO::build_version_command>(*this, L.Ptr);
4336 }
4337 
4338 MachO::build_tool_version
getBuildToolVersion(unsigned index) const4339 MachOObjectFile::getBuildToolVersion(unsigned index) const {
4340   return getStruct<MachO::build_tool_version>(*this, BuildTools[index]);
4341 }
4342 
4343 MachO::dylib_command
getDylibIDLoadCommand(const LoadCommandInfo & L) const4344 MachOObjectFile::getDylibIDLoadCommand(const LoadCommandInfo &L) const {
4345   return getStruct<MachO::dylib_command>(*this, L.Ptr);
4346 }
4347 
4348 MachO::dyld_info_command
getDyldInfoLoadCommand(const LoadCommandInfo & L) const4349 MachOObjectFile::getDyldInfoLoadCommand(const LoadCommandInfo &L) const {
4350   return getStruct<MachO::dyld_info_command>(*this, L.Ptr);
4351 }
4352 
4353 MachO::dylinker_command
getDylinkerCommand(const LoadCommandInfo & L) const4354 MachOObjectFile::getDylinkerCommand(const LoadCommandInfo &L) const {
4355   return getStruct<MachO::dylinker_command>(*this, L.Ptr);
4356 }
4357 
4358 MachO::uuid_command
getUuidCommand(const LoadCommandInfo & L) const4359 MachOObjectFile::getUuidCommand(const LoadCommandInfo &L) const {
4360   return getStruct<MachO::uuid_command>(*this, L.Ptr);
4361 }
4362 
4363 MachO::rpath_command
getRpathCommand(const LoadCommandInfo & L) const4364 MachOObjectFile::getRpathCommand(const LoadCommandInfo &L) const {
4365   return getStruct<MachO::rpath_command>(*this, L.Ptr);
4366 }
4367 
4368 MachO::source_version_command
getSourceVersionCommand(const LoadCommandInfo & L) const4369 MachOObjectFile::getSourceVersionCommand(const LoadCommandInfo &L) const {
4370   return getStruct<MachO::source_version_command>(*this, L.Ptr);
4371 }
4372 
4373 MachO::entry_point_command
getEntryPointCommand(const LoadCommandInfo & L) const4374 MachOObjectFile::getEntryPointCommand(const LoadCommandInfo &L) const {
4375   return getStruct<MachO::entry_point_command>(*this, L.Ptr);
4376 }
4377 
4378 MachO::encryption_info_command
getEncryptionInfoCommand(const LoadCommandInfo & L) const4379 MachOObjectFile::getEncryptionInfoCommand(const LoadCommandInfo &L) const {
4380   return getStruct<MachO::encryption_info_command>(*this, L.Ptr);
4381 }
4382 
4383 MachO::encryption_info_command_64
getEncryptionInfoCommand64(const LoadCommandInfo & L) const4384 MachOObjectFile::getEncryptionInfoCommand64(const LoadCommandInfo &L) const {
4385   return getStruct<MachO::encryption_info_command_64>(*this, L.Ptr);
4386 }
4387 
4388 MachO::sub_framework_command
getSubFrameworkCommand(const LoadCommandInfo & L) const4389 MachOObjectFile::getSubFrameworkCommand(const LoadCommandInfo &L) const {
4390   return getStruct<MachO::sub_framework_command>(*this, L.Ptr);
4391 }
4392 
4393 MachO::sub_umbrella_command
getSubUmbrellaCommand(const LoadCommandInfo & L) const4394 MachOObjectFile::getSubUmbrellaCommand(const LoadCommandInfo &L) const {
4395   return getStruct<MachO::sub_umbrella_command>(*this, L.Ptr);
4396 }
4397 
4398 MachO::sub_library_command
getSubLibraryCommand(const LoadCommandInfo & L) const4399 MachOObjectFile::getSubLibraryCommand(const LoadCommandInfo &L) const {
4400   return getStruct<MachO::sub_library_command>(*this, L.Ptr);
4401 }
4402 
4403 MachO::sub_client_command
getSubClientCommand(const LoadCommandInfo & L) const4404 MachOObjectFile::getSubClientCommand(const LoadCommandInfo &L) const {
4405   return getStruct<MachO::sub_client_command>(*this, L.Ptr);
4406 }
4407 
4408 MachO::routines_command
getRoutinesCommand(const LoadCommandInfo & L) const4409 MachOObjectFile::getRoutinesCommand(const LoadCommandInfo &L) const {
4410   return getStruct<MachO::routines_command>(*this, L.Ptr);
4411 }
4412 
4413 MachO::routines_command_64
getRoutinesCommand64(const LoadCommandInfo & L) const4414 MachOObjectFile::getRoutinesCommand64(const LoadCommandInfo &L) const {
4415   return getStruct<MachO::routines_command_64>(*this, L.Ptr);
4416 }
4417 
4418 MachO::thread_command
getThreadCommand(const LoadCommandInfo & L) const4419 MachOObjectFile::getThreadCommand(const LoadCommandInfo &L) const {
4420   return getStruct<MachO::thread_command>(*this, L.Ptr);
4421 }
4422 
4423 MachO::any_relocation_info
getRelocation(DataRefImpl Rel) const4424 MachOObjectFile::getRelocation(DataRefImpl Rel) const {
4425   uint32_t Offset;
4426   if (getHeader().filetype == MachO::MH_OBJECT) {
4427     DataRefImpl Sec;
4428     Sec.d.a = Rel.d.a;
4429     if (is64Bit()) {
4430       MachO::section_64 Sect = getSection64(Sec);
4431       Offset = Sect.reloff;
4432     } else {
4433       MachO::section Sect = getSection(Sec);
4434       Offset = Sect.reloff;
4435     }
4436   } else {
4437     MachO::dysymtab_command DysymtabLoadCmd = getDysymtabLoadCommand();
4438     if (Rel.d.a == 0)
4439       Offset = DysymtabLoadCmd.extreloff; // Offset to the external relocations
4440     else
4441       Offset = DysymtabLoadCmd.locreloff; // Offset to the local relocations
4442   }
4443 
4444   auto P = reinterpret_cast<const MachO::any_relocation_info *>(
4445       getPtr(*this, Offset)) + Rel.d.b;
4446   return getStruct<MachO::any_relocation_info>(
4447       *this, reinterpret_cast<const char *>(P));
4448 }
4449 
4450 MachO::data_in_code_entry
getDice(DataRefImpl Rel) const4451 MachOObjectFile::getDice(DataRefImpl Rel) const {
4452   const char *P = reinterpret_cast<const char *>(Rel.p);
4453   return getStruct<MachO::data_in_code_entry>(*this, P);
4454 }
4455 
getHeader() const4456 const MachO::mach_header &MachOObjectFile::getHeader() const {
4457   return Header;
4458 }
4459 
getHeader64() const4460 const MachO::mach_header_64 &MachOObjectFile::getHeader64() const {
4461   assert(is64Bit());
4462   return Header64;
4463 }
4464 
getIndirectSymbolTableEntry(const MachO::dysymtab_command & DLC,unsigned Index) const4465 uint32_t MachOObjectFile::getIndirectSymbolTableEntry(
4466                                              const MachO::dysymtab_command &DLC,
4467                                              unsigned Index) const {
4468   uint64_t Offset = DLC.indirectsymoff + Index * sizeof(uint32_t);
4469   return getStruct<uint32_t>(*this, getPtr(*this, Offset));
4470 }
4471 
4472 MachO::data_in_code_entry
getDataInCodeTableEntry(uint32_t DataOffset,unsigned Index) const4473 MachOObjectFile::getDataInCodeTableEntry(uint32_t DataOffset,
4474                                          unsigned Index) const {
4475   uint64_t Offset = DataOffset + Index * sizeof(MachO::data_in_code_entry);
4476   return getStruct<MachO::data_in_code_entry>(*this, getPtr(*this, Offset));
4477 }
4478 
getSymtabLoadCommand() const4479 MachO::symtab_command MachOObjectFile::getSymtabLoadCommand() const {
4480   if (SymtabLoadCmd)
4481     return getStruct<MachO::symtab_command>(*this, SymtabLoadCmd);
4482 
4483   // If there is no SymtabLoadCmd return a load command with zero'ed fields.
4484   MachO::symtab_command Cmd;
4485   Cmd.cmd = MachO::LC_SYMTAB;
4486   Cmd.cmdsize = sizeof(MachO::symtab_command);
4487   Cmd.symoff = 0;
4488   Cmd.nsyms = 0;
4489   Cmd.stroff = 0;
4490   Cmd.strsize = 0;
4491   return Cmd;
4492 }
4493 
getDysymtabLoadCommand() const4494 MachO::dysymtab_command MachOObjectFile::getDysymtabLoadCommand() const {
4495   if (DysymtabLoadCmd)
4496     return getStruct<MachO::dysymtab_command>(*this, DysymtabLoadCmd);
4497 
4498   // If there is no DysymtabLoadCmd return a load command with zero'ed fields.
4499   MachO::dysymtab_command Cmd;
4500   Cmd.cmd = MachO::LC_DYSYMTAB;
4501   Cmd.cmdsize = sizeof(MachO::dysymtab_command);
4502   Cmd.ilocalsym = 0;
4503   Cmd.nlocalsym = 0;
4504   Cmd.iextdefsym = 0;
4505   Cmd.nextdefsym = 0;
4506   Cmd.iundefsym = 0;
4507   Cmd.nundefsym = 0;
4508   Cmd.tocoff = 0;
4509   Cmd.ntoc = 0;
4510   Cmd.modtaboff = 0;
4511   Cmd.nmodtab = 0;
4512   Cmd.extrefsymoff = 0;
4513   Cmd.nextrefsyms = 0;
4514   Cmd.indirectsymoff = 0;
4515   Cmd.nindirectsyms = 0;
4516   Cmd.extreloff = 0;
4517   Cmd.nextrel = 0;
4518   Cmd.locreloff = 0;
4519   Cmd.nlocrel = 0;
4520   return Cmd;
4521 }
4522 
4523 MachO::linkedit_data_command
getDataInCodeLoadCommand() const4524 MachOObjectFile::getDataInCodeLoadCommand() const {
4525   if (DataInCodeLoadCmd)
4526     return getStruct<MachO::linkedit_data_command>(*this, DataInCodeLoadCmd);
4527 
4528   // If there is no DataInCodeLoadCmd return a load command with zero'ed fields.
4529   MachO::linkedit_data_command Cmd;
4530   Cmd.cmd = MachO::LC_DATA_IN_CODE;
4531   Cmd.cmdsize = sizeof(MachO::linkedit_data_command);
4532   Cmd.dataoff = 0;
4533   Cmd.datasize = 0;
4534   return Cmd;
4535 }
4536 
4537 MachO::linkedit_data_command
getLinkOptHintsLoadCommand() const4538 MachOObjectFile::getLinkOptHintsLoadCommand() const {
4539   if (LinkOptHintsLoadCmd)
4540     return getStruct<MachO::linkedit_data_command>(*this, LinkOptHintsLoadCmd);
4541 
4542   // If there is no LinkOptHintsLoadCmd return a load command with zero'ed
4543   // fields.
4544   MachO::linkedit_data_command Cmd;
4545   Cmd.cmd = MachO::LC_LINKER_OPTIMIZATION_HINT;
4546   Cmd.cmdsize = sizeof(MachO::linkedit_data_command);
4547   Cmd.dataoff = 0;
4548   Cmd.datasize = 0;
4549   return Cmd;
4550 }
4551 
getDyldInfoRebaseOpcodes() const4552 ArrayRef<uint8_t> MachOObjectFile::getDyldInfoRebaseOpcodes() const {
4553   if (!DyldInfoLoadCmd)
4554     return None;
4555 
4556   auto DyldInfoOrErr =
4557     getStructOrErr<MachO::dyld_info_command>(*this, DyldInfoLoadCmd);
4558   if (!DyldInfoOrErr)
4559     return None;
4560   MachO::dyld_info_command DyldInfo = DyldInfoOrErr.get();
4561   const uint8_t *Ptr =
4562       reinterpret_cast<const uint8_t *>(getPtr(*this, DyldInfo.rebase_off));
4563   return makeArrayRef(Ptr, DyldInfo.rebase_size);
4564 }
4565 
getDyldInfoBindOpcodes() const4566 ArrayRef<uint8_t> MachOObjectFile::getDyldInfoBindOpcodes() const {
4567   if (!DyldInfoLoadCmd)
4568     return None;
4569 
4570   auto DyldInfoOrErr =
4571     getStructOrErr<MachO::dyld_info_command>(*this, DyldInfoLoadCmd);
4572   if (!DyldInfoOrErr)
4573     return None;
4574   MachO::dyld_info_command DyldInfo = DyldInfoOrErr.get();
4575   const uint8_t *Ptr =
4576       reinterpret_cast<const uint8_t *>(getPtr(*this, DyldInfo.bind_off));
4577   return makeArrayRef(Ptr, DyldInfo.bind_size);
4578 }
4579 
getDyldInfoWeakBindOpcodes() const4580 ArrayRef<uint8_t> MachOObjectFile::getDyldInfoWeakBindOpcodes() const {
4581   if (!DyldInfoLoadCmd)
4582     return None;
4583 
4584   auto DyldInfoOrErr =
4585     getStructOrErr<MachO::dyld_info_command>(*this, DyldInfoLoadCmd);
4586   if (!DyldInfoOrErr)
4587     return None;
4588   MachO::dyld_info_command DyldInfo = DyldInfoOrErr.get();
4589   const uint8_t *Ptr =
4590       reinterpret_cast<const uint8_t *>(getPtr(*this, DyldInfo.weak_bind_off));
4591   return makeArrayRef(Ptr, DyldInfo.weak_bind_size);
4592 }
4593 
getDyldInfoLazyBindOpcodes() const4594 ArrayRef<uint8_t> MachOObjectFile::getDyldInfoLazyBindOpcodes() const {
4595   if (!DyldInfoLoadCmd)
4596     return None;
4597 
4598   auto DyldInfoOrErr =
4599     getStructOrErr<MachO::dyld_info_command>(*this, DyldInfoLoadCmd);
4600   if (!DyldInfoOrErr)
4601     return None;
4602   MachO::dyld_info_command DyldInfo = DyldInfoOrErr.get();
4603   const uint8_t *Ptr =
4604       reinterpret_cast<const uint8_t *>(getPtr(*this, DyldInfo.lazy_bind_off));
4605   return makeArrayRef(Ptr, DyldInfo.lazy_bind_size);
4606 }
4607 
getDyldInfoExportsTrie() const4608 ArrayRef<uint8_t> MachOObjectFile::getDyldInfoExportsTrie() const {
4609   if (!DyldInfoLoadCmd)
4610     return None;
4611 
4612   auto DyldInfoOrErr =
4613     getStructOrErr<MachO::dyld_info_command>(*this, DyldInfoLoadCmd);
4614   if (!DyldInfoOrErr)
4615     return None;
4616   MachO::dyld_info_command DyldInfo = DyldInfoOrErr.get();
4617   const uint8_t *Ptr =
4618       reinterpret_cast<const uint8_t *>(getPtr(*this, DyldInfo.export_off));
4619   return makeArrayRef(Ptr, DyldInfo.export_size);
4620 }
4621 
getUuid() const4622 ArrayRef<uint8_t> MachOObjectFile::getUuid() const {
4623   if (!UuidLoadCmd)
4624     return None;
4625   // Returning a pointer is fine as uuid doesn't need endian swapping.
4626   const char *Ptr = UuidLoadCmd + offsetof(MachO::uuid_command, uuid);
4627   return makeArrayRef(reinterpret_cast<const uint8_t *>(Ptr), 16);
4628 }
4629 
getStringTableData() const4630 StringRef MachOObjectFile::getStringTableData() const {
4631   MachO::symtab_command S = getSymtabLoadCommand();
4632   return getData().substr(S.stroff, S.strsize);
4633 }
4634 
is64Bit() const4635 bool MachOObjectFile::is64Bit() const {
4636   return getType() == getMachOType(false, true) ||
4637     getType() == getMachOType(true, true);
4638 }
4639 
ReadULEB128s(uint64_t Index,SmallVectorImpl<uint64_t> & Out) const4640 void MachOObjectFile::ReadULEB128s(uint64_t Index,
4641                                    SmallVectorImpl<uint64_t> &Out) const {
4642   DataExtractor extractor(ObjectFile::getData(), true, 0);
4643 
4644   uint64_t offset = Index;
4645   uint64_t data = 0;
4646   while (uint64_t delta = extractor.getULEB128(&offset)) {
4647     data += delta;
4648     Out.push_back(data);
4649   }
4650 }
4651 
isRelocatableObject() const4652 bool MachOObjectFile::isRelocatableObject() const {
4653   return getHeader().filetype == MachO::MH_OBJECT;
4654 }
4655 
4656 Expected<std::unique_ptr<MachOObjectFile>>
createMachOObjectFile(MemoryBufferRef Buffer,uint32_t UniversalCputype,uint32_t UniversalIndex)4657 ObjectFile::createMachOObjectFile(MemoryBufferRef Buffer,
4658                                   uint32_t UniversalCputype,
4659                                   uint32_t UniversalIndex) {
4660   StringRef Magic = Buffer.getBuffer().slice(0, 4);
4661   if (Magic == "\xFE\xED\xFA\xCE")
4662     return MachOObjectFile::create(Buffer, false, false,
4663                                    UniversalCputype, UniversalIndex);
4664   if (Magic == "\xCE\xFA\xED\xFE")
4665     return MachOObjectFile::create(Buffer, true, false,
4666                                    UniversalCputype, UniversalIndex);
4667   if (Magic == "\xFE\xED\xFA\xCF")
4668     return MachOObjectFile::create(Buffer, false, true,
4669                                    UniversalCputype, UniversalIndex);
4670   if (Magic == "\xCF\xFA\xED\xFE")
4671     return MachOObjectFile::create(Buffer, true, true,
4672                                    UniversalCputype, UniversalIndex);
4673   return make_error<GenericBinaryError>("Unrecognized MachO magic number",
4674                                         object_error::invalid_file_type);
4675 }
4676 
mapDebugSectionName(StringRef Name) const4677 StringRef MachOObjectFile::mapDebugSectionName(StringRef Name) const {
4678   return StringSwitch<StringRef>(Name)
4679       .Case("debug_str_offs", "debug_str_offsets")
4680       .Default(Name);
4681 }
4682