1 //===- ELFObjectFile.h - ELF object file implementation ---------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file declares the ELFObjectFile template class.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_OBJECT_ELFOBJECTFILE_H
15 #define LLVM_OBJECT_ELFOBJECTFILE_H
16 
17 #include "llvm/ADT/DenseMap.h"
18 #include "llvm/ADT/PointerIntPair.h"
19 #include "llvm/ADT/SmallVector.h"
20 #include "llvm/ADT/StringSwitch.h"
21 #include "llvm/ADT/Triple.h"
22 #include "llvm/Object/ELF.h"
23 #include "llvm/Object/ObjectFile.h"
24 #include "llvm/Support/Casting.h"
25 #include "llvm/Support/ELF.h"
26 #include "llvm/Support/Endian.h"
27 #include "llvm/Support/ErrorHandling.h"
28 #include "llvm/Support/MemoryBuffer.h"
29 #include "llvm/Support/raw_ostream.h"
30 #include <algorithm>
31 #include <cctype>
32 #include <limits>
33 #include <utility>
34 
35 namespace llvm {
36 namespace object {
37 
38 class ELFObjectFileBase : public ObjectFile {
39 protected:
40   ELFObjectFileBase(unsigned int Type, MemoryBufferRef Source);
41 
42 public:
43   virtual std::error_code getRelocationAddend(DataRefImpl Rel,
44                                               int64_t &Res) const = 0;
45   virtual std::pair<symbol_iterator, symbol_iterator>
46   getELFDynamicSymbolIterators() const = 0;
47 
48   virtual std::error_code getSymbolVersion(SymbolRef Symb, StringRef &Version,
49                                            bool &IsDefault) const = 0;
50 
51   virtual uint64_t getSectionFlags(SectionRef Sec) const = 0;
52   virtual uint32_t getSectionType(SectionRef Sec) const = 0;
53 
classof(const Binary * v)54   static inline bool classof(const Binary *v) { return v->isELF(); }
55 };
56 
57 template <class ELFT> class ELFObjectFile : public ELFObjectFileBase {
58 public:
59   LLVM_ELF_IMPORT_TYPES_ELFT(ELFT)
60 
61   typedef typename ELFFile<ELFT>::uintX_t uintX_t;
62 
63   typedef typename ELFFile<ELFT>::Elf_Sym Elf_Sym;
64   typedef typename ELFFile<ELFT>::Elf_Shdr Elf_Shdr;
65   typedef typename ELFFile<ELFT>::Elf_Ehdr Elf_Ehdr;
66   typedef typename ELFFile<ELFT>::Elf_Rel Elf_Rel;
67   typedef typename ELFFile<ELFT>::Elf_Rela Elf_Rela;
68   typedef typename ELFFile<ELFT>::Elf_Dyn Elf_Dyn;
69 
70   typedef typename ELFFile<ELFT>::Elf_Sym_Iter Elf_Sym_Iter;
71   typedef typename ELFFile<ELFT>::Elf_Shdr_Iter Elf_Shdr_Iter;
72   typedef typename ELFFile<ELFT>::Elf_Dyn_Iter Elf_Dyn_Iter;
73 
74 protected:
75   ELFFile<ELFT> EF;
76 
77   void moveSymbolNext(DataRefImpl &Symb) const override;
78   std::error_code getSymbolName(DataRefImpl Symb,
79                                 StringRef &Res) const override;
80   std::error_code getSymbolAddress(DataRefImpl Symb,
81                                    uint64_t &Res) const override;
82   std::error_code getSymbolAlignment(DataRefImpl Symb,
83                                      uint32_t &Res) const override;
84   std::error_code getSymbolSize(DataRefImpl Symb, uint64_t &Res) const override;
85   uint32_t getSymbolFlags(DataRefImpl Symb) const override;
86   std::error_code getSymbolOther(DataRefImpl Symb, uint8_t &Res) const override;
87   std::error_code getSymbolType(DataRefImpl Symb,
88                                 SymbolRef::Type &Res) const override;
89   std::error_code getSymbolSection(DataRefImpl Symb,
90                                    section_iterator &Res) const override;
91 
92   void moveSectionNext(DataRefImpl &Sec) const override;
93   std::error_code getSectionName(DataRefImpl Sec,
94                                  StringRef &Res) const override;
95   uint64_t getSectionAddress(DataRefImpl Sec) const override;
96   uint64_t getSectionSize(DataRefImpl Sec) const override;
97   std::error_code getSectionContents(DataRefImpl Sec,
98                                      StringRef &Res) const override;
99   uint64_t getSectionAlignment(DataRefImpl Sec) const override;
100   bool isSectionText(DataRefImpl Sec) const override;
101   bool isSectionData(DataRefImpl Sec) const override;
102   bool isSectionBSS(DataRefImpl Sec) const override;
103   bool isSectionVirtual(DataRefImpl Sec) const override;
104   bool sectionContainsSymbol(DataRefImpl Sec, DataRefImpl Symb) const override;
105   relocation_iterator section_rel_begin(DataRefImpl Sec) const override;
106   relocation_iterator section_rel_end(DataRefImpl Sec) const override;
107   section_iterator getRelocatedSection(DataRefImpl Sec) const override;
108 
109   void moveRelocationNext(DataRefImpl &Rel) const override;
110   std::error_code getRelocationAddress(DataRefImpl Rel,
111                                        uint64_t &Res) const override;
112   std::error_code getRelocationOffset(DataRefImpl Rel,
113                                       uint64_t &Res) const override;
114   symbol_iterator getRelocationSymbol(DataRefImpl Rel) const override;
115   std::error_code getRelocationType(DataRefImpl Rel,
116                                     uint64_t &Res) const override;
117   std::error_code
118   getRelocationTypeName(DataRefImpl Rel,
119                         SmallVectorImpl<char> &Result) const override;
120   std::error_code
121   getRelocationValueString(DataRefImpl Rel,
122                            SmallVectorImpl<char> &Result) const override;
123 
124   uint64_t getROffset(DataRefImpl Rel) const;
125   StringRef getRelocationTypeName(uint32_t Type) const;
126 
127   /// \brief Get the relocation section that contains \a Rel.
getRelSection(DataRefImpl Rel)128   const Elf_Shdr *getRelSection(DataRefImpl Rel) const {
129     return EF.getSection(Rel.d.a);
130   }
131 
132   const Elf_Rel *getRel(DataRefImpl Rel) const;
133   const Elf_Rela *getRela(DataRefImpl Rela) const;
134 
toELFSymIter(DataRefImpl Symb)135   Elf_Sym_Iter toELFSymIter(DataRefImpl Symb) const {
136     bool IsDynamic = Symb.p & 1;
137     if (IsDynamic)
138       return Elf_Sym_Iter(
139           EF.begin_dynamic_symbols().getEntSize(),
140           reinterpret_cast<const char *>(Symb.p & ~uintptr_t(1)), IsDynamic);
141     return Elf_Sym_Iter(EF.begin_symbols().getEntSize(),
142                         reinterpret_cast<const char *>(Symb.p), IsDynamic);
143   }
144 
toDRI(Elf_Sym_Iter Symb)145   DataRefImpl toDRI(Elf_Sym_Iter Symb) const {
146     DataRefImpl DRI;
147     DRI.p = reinterpret_cast<uintptr_t>(Symb.get()) |
148       static_cast<uintptr_t>(Symb.isDynamic());
149     return DRI;
150   }
151 
toELFShdrIter(DataRefImpl Sec)152   Elf_Shdr_Iter toELFShdrIter(DataRefImpl Sec) const {
153     return Elf_Shdr_Iter(EF.getHeader()->e_shentsize,
154                          reinterpret_cast<const char *>(Sec.p));
155   }
156 
toDRI(Elf_Shdr_Iter Sec)157   DataRefImpl toDRI(Elf_Shdr_Iter Sec) const {
158     DataRefImpl DRI;
159     DRI.p = reinterpret_cast<uintptr_t>(Sec.get());
160     return DRI;
161   }
162 
toDRI(const Elf_Shdr * Sec)163   DataRefImpl toDRI(const Elf_Shdr *Sec) const {
164     DataRefImpl DRI;
165     DRI.p = reinterpret_cast<uintptr_t>(Sec);
166     return DRI;
167   }
168 
toELFDynIter(DataRefImpl Dyn)169   Elf_Dyn_Iter toELFDynIter(DataRefImpl Dyn) const {
170     return Elf_Dyn_Iter(EF.begin_dynamic_table().getEntSize(),
171                         reinterpret_cast<const char *>(Dyn.p));
172   }
173 
toDRI(Elf_Dyn_Iter Dyn)174   DataRefImpl toDRI(Elf_Dyn_Iter Dyn) const {
175     DataRefImpl DRI;
176     DRI.p = reinterpret_cast<uintptr_t>(Dyn.get());
177     return DRI;
178   }
179 
isExportedToOtherDSO(const Elf_Sym * ESym)180   bool isExportedToOtherDSO(const Elf_Sym *ESym) const {
181     unsigned char Binding = ESym->getBinding();
182     unsigned char Visibility = ESym->getVisibility();
183 
184     // A symbol is exported if its binding is either GLOBAL or WEAK, and its
185     // visibility is either DEFAULT or PROTECTED. All other symbols are not
186     // exported.
187     if ((Binding == ELF::STB_GLOBAL || Binding == ELF::STB_WEAK) &&
188         (Visibility == ELF::STV_DEFAULT || Visibility == ELF::STV_PROTECTED))
189       return true;
190 
191     return false;
192   }
193 
194   // This flag is used for classof, to distinguish ELFObjectFile from
195   // its subclass. If more subclasses will be created, this flag will
196   // have to become an enum.
197   bool isDyldELFObject;
198 
199 public:
200   ELFObjectFile(MemoryBufferRef Object, std::error_code &EC);
201 
202   const Elf_Sym *getSymbol(DataRefImpl Symb) const;
203 
204   basic_symbol_iterator symbol_begin_impl() const override;
205   basic_symbol_iterator symbol_end_impl() const override;
206 
207   symbol_iterator dynamic_symbol_begin() const;
208   symbol_iterator dynamic_symbol_end() const;
209 
210   section_iterator section_begin() const override;
211   section_iterator section_end() const override;
212 
213   std::error_code getRelocationAddend(DataRefImpl Rel,
214                                       int64_t &Res) const override;
215   std::error_code getSymbolVersion(SymbolRef Symb, StringRef &Version,
216                                    bool &IsDefault) const override;
217 
218   uint64_t getSectionFlags(SectionRef Sec) const override;
219   uint32_t getSectionType(SectionRef Sec) const override;
220 
221   uint8_t getBytesInAddress() const override;
222   StringRef getFileFormatName() const override;
223   unsigned getArch() const override;
224   StringRef getLoadName() const;
225 
getPlatformFlags(unsigned & Result)226   std::error_code getPlatformFlags(unsigned &Result) const override {
227     Result = EF.getHeader()->e_flags;
228     return object_error::success;
229   }
230 
getELFFile()231   const ELFFile<ELFT> *getELFFile() const { return &EF; }
232 
isDyldType()233   bool isDyldType() const { return isDyldELFObject; }
classof(const Binary * v)234   static inline bool classof(const Binary *v) {
235     return v->getType() == getELFType(ELFT::TargetEndianness == support::little,
236                                       ELFT::Is64Bits);
237   }
238 
239   std::pair<symbol_iterator, symbol_iterator>
240   getELFDynamicSymbolIterators() const override;
241 
242   bool isRelocatableObject() const override;
243 };
244 
245 // Use an alignment of 2 for the typedefs since that is the worst case for
246 // ELF files in archives.
247 typedef ELFObjectFile<ELFType<support::little, 2, false> > ELF32LEObjectFile;
248 typedef ELFObjectFile<ELFType<support::little, 2, true> > ELF64LEObjectFile;
249 typedef ELFObjectFile<ELFType<support::big, 2, false> > ELF32BEObjectFile;
250 typedef ELFObjectFile<ELFType<support::big, 2, true> > ELF64BEObjectFile;
251 
252 template <class ELFT>
moveSymbolNext(DataRefImpl & Symb)253 void ELFObjectFile<ELFT>::moveSymbolNext(DataRefImpl &Symb) const {
254   Symb = toDRI(++toELFSymIter(Symb));
255 }
256 
257 template <class ELFT>
getSymbolName(DataRefImpl Symb,StringRef & Result)258 std::error_code ELFObjectFile<ELFT>::getSymbolName(DataRefImpl Symb,
259                                                    StringRef &Result) const {
260   ErrorOr<StringRef> Name = EF.getSymbolName(toELFSymIter(Symb));
261   if (!Name)
262     return Name.getError();
263   Result = *Name;
264   return object_error::success;
265 }
266 
267 template <class ELFT>
getSymbolVersion(SymbolRef SymRef,StringRef & Version,bool & IsDefault)268 std::error_code ELFObjectFile<ELFT>::getSymbolVersion(SymbolRef SymRef,
269                                                       StringRef &Version,
270                                                       bool &IsDefault) const {
271   DataRefImpl Symb = SymRef.getRawDataRefImpl();
272   const Elf_Sym *symb = getSymbol(Symb);
273   ErrorOr<StringRef> Ver =
274       EF.getSymbolVersion(EF.getSection(Symb.d.b), symb, IsDefault);
275   if (!Ver)
276     return Ver.getError();
277   Version = *Ver;
278   return object_error::success;
279 }
280 
281 template <class ELFT>
getSectionFlags(SectionRef Sec)282 uint64_t ELFObjectFile<ELFT>::getSectionFlags(SectionRef Sec) const {
283   DataRefImpl DRI = Sec.getRawDataRefImpl();
284   return toELFShdrIter(DRI)->sh_flags;
285 }
286 
287 template <class ELFT>
getSectionType(SectionRef Sec)288 uint32_t ELFObjectFile<ELFT>::getSectionType(SectionRef Sec) const {
289   DataRefImpl DRI = Sec.getRawDataRefImpl();
290   return toELFShdrIter(DRI)->sh_type;
291 }
292 
293 template <class ELFT>
getSymbolAddress(DataRefImpl Symb,uint64_t & Result)294 std::error_code ELFObjectFile<ELFT>::getSymbolAddress(DataRefImpl Symb,
295                                                       uint64_t &Result) const {
296   const Elf_Sym *ESym = getSymbol(Symb);
297   switch (EF.getSymbolTableIndex(ESym)) {
298   case ELF::SHN_COMMON:
299   case ELF::SHN_UNDEF:
300     Result = UnknownAddressOrSize;
301     return object_error::success;
302   case ELF::SHN_ABS:
303     Result = ESym->st_value;
304     return object_error::success;
305   default:
306     break;
307   }
308 
309   const Elf_Ehdr *Header = EF.getHeader();
310   Result = ESym->st_value;
311 
312   // Clear the ARM/Thumb or microMIPS indicator flag.
313   if ((Header->e_machine == ELF::EM_ARM || Header->e_machine == ELF::EM_MIPS) &&
314       ESym->getType() == ELF::STT_FUNC)
315     Result &= ~1;
316 
317   if (Header->e_type == ELF::ET_REL) {
318     const typename ELFFile<ELFT>::Elf_Shdr * Section = EF.getSection(ESym);
319     if (Section != nullptr)
320       Result += Section->sh_addr;
321   }
322 
323   return object_error::success;
324 }
325 
326 template <class ELFT>
getSymbolAlignment(DataRefImpl Symb,uint32_t & Res)327 std::error_code ELFObjectFile<ELFT>::getSymbolAlignment(DataRefImpl Symb,
328                                                         uint32_t &Res) const {
329   Elf_Sym_Iter Sym = toELFSymIter(Symb);
330   if (Sym->st_shndx == ELF::SHN_COMMON)
331     Res = Sym->st_value;
332   else
333     Res = 0;
334   return object_error::success;
335 }
336 
337 template <class ELFT>
getSymbolSize(DataRefImpl Symb,uint64_t & Result)338 std::error_code ELFObjectFile<ELFT>::getSymbolSize(DataRefImpl Symb,
339                                                    uint64_t &Result) const {
340   Result = toELFSymIter(Symb)->st_size;
341   return object_error::success;
342 }
343 
344 template <class ELFT>
getSymbolOther(DataRefImpl Symb,uint8_t & Result)345 std::error_code ELFObjectFile<ELFT>::getSymbolOther(DataRefImpl Symb,
346                                                     uint8_t &Result) const {
347   Result = toELFSymIter(Symb)->st_other;
348   return object_error::success;
349 }
350 
351 template <class ELFT>
352 std::error_code
getSymbolType(DataRefImpl Symb,SymbolRef::Type & Result)353 ELFObjectFile<ELFT>::getSymbolType(DataRefImpl Symb,
354                                    SymbolRef::Type &Result) const {
355   const Elf_Sym *ESym = getSymbol(Symb);
356 
357   switch (ESym->getType()) {
358   case ELF::STT_NOTYPE:
359     Result = SymbolRef::ST_Unknown;
360     break;
361   case ELF::STT_SECTION:
362     Result = SymbolRef::ST_Debug;
363     break;
364   case ELF::STT_FILE:
365     Result = SymbolRef::ST_File;
366     break;
367   case ELF::STT_FUNC:
368     Result = SymbolRef::ST_Function;
369     break;
370   case ELF::STT_OBJECT:
371   case ELF::STT_COMMON:
372   case ELF::STT_TLS:
373     Result = SymbolRef::ST_Data;
374     break;
375   default:
376     Result = SymbolRef::ST_Other;
377     break;
378   }
379   return object_error::success;
380 }
381 
382 template <class ELFT>
getSymbolFlags(DataRefImpl Symb)383 uint32_t ELFObjectFile<ELFT>::getSymbolFlags(DataRefImpl Symb) const {
384   Elf_Sym_Iter EIter = toELFSymIter(Symb);
385   const Elf_Sym *ESym = &*EIter;
386 
387   uint32_t Result = SymbolRef::SF_None;
388 
389   if (ESym->getBinding() != ELF::STB_LOCAL)
390     Result |= SymbolRef::SF_Global;
391 
392   if (ESym->getBinding() == ELF::STB_WEAK)
393     Result |= SymbolRef::SF_Weak;
394 
395   if (ESym->st_shndx == ELF::SHN_ABS)
396     Result |= SymbolRef::SF_Absolute;
397 
398   if (ESym->getType() == ELF::STT_FILE || ESym->getType() == ELF::STT_SECTION ||
399       EIter == EF.begin_symbols() || EIter == EF.begin_dynamic_symbols())
400     Result |= SymbolRef::SF_FormatSpecific;
401 
402   if (EF.getSymbolTableIndex(ESym) == ELF::SHN_UNDEF)
403     Result |= SymbolRef::SF_Undefined;
404 
405   if (ESym->getType() == ELF::STT_COMMON ||
406       EF.getSymbolTableIndex(ESym) == ELF::SHN_COMMON)
407     Result |= SymbolRef::SF_Common;
408 
409   if (isExportedToOtherDSO(ESym))
410     Result |= SymbolRef::SF_Exported;
411 
412   return Result;
413 }
414 
415 template <class ELFT>
416 std::error_code
getSymbolSection(DataRefImpl Symb,section_iterator & Res)417 ELFObjectFile<ELFT>::getSymbolSection(DataRefImpl Symb,
418                                       section_iterator &Res) const {
419   const Elf_Sym *ESym = getSymbol(Symb);
420   const Elf_Shdr *ESec = EF.getSection(ESym);
421   if (!ESec)
422     Res = section_end();
423   else {
424     DataRefImpl Sec;
425     Sec.p = reinterpret_cast<intptr_t>(ESec);
426     Res = section_iterator(SectionRef(Sec, this));
427   }
428   return object_error::success;
429 }
430 
431 template <class ELFT>
moveSectionNext(DataRefImpl & Sec)432 void ELFObjectFile<ELFT>::moveSectionNext(DataRefImpl &Sec) const {
433   Sec = toDRI(++toELFShdrIter(Sec));
434 }
435 
436 template <class ELFT>
getSectionName(DataRefImpl Sec,StringRef & Result)437 std::error_code ELFObjectFile<ELFT>::getSectionName(DataRefImpl Sec,
438                                                     StringRef &Result) const {
439   ErrorOr<StringRef> Name = EF.getSectionName(&*toELFShdrIter(Sec));
440   if (!Name)
441     return Name.getError();
442   Result = *Name;
443   return object_error::success;
444 }
445 
446 template <class ELFT>
getSectionAddress(DataRefImpl Sec)447 uint64_t ELFObjectFile<ELFT>::getSectionAddress(DataRefImpl Sec) const {
448   return toELFShdrIter(Sec)->sh_addr;
449 }
450 
451 template <class ELFT>
getSectionSize(DataRefImpl Sec)452 uint64_t ELFObjectFile<ELFT>::getSectionSize(DataRefImpl Sec) const {
453   return toELFShdrIter(Sec)->sh_size;
454 }
455 
456 template <class ELFT>
457 std::error_code
getSectionContents(DataRefImpl Sec,StringRef & Result)458 ELFObjectFile<ELFT>::getSectionContents(DataRefImpl Sec,
459                                         StringRef &Result) const {
460   Elf_Shdr_Iter EShdr = toELFShdrIter(Sec);
461   Result = StringRef((const char *)base() + EShdr->sh_offset, EShdr->sh_size);
462   return object_error::success;
463 }
464 
465 template <class ELFT>
getSectionAlignment(DataRefImpl Sec)466 uint64_t ELFObjectFile<ELFT>::getSectionAlignment(DataRefImpl Sec) const {
467   return toELFShdrIter(Sec)->sh_addralign;
468 }
469 
470 template <class ELFT>
isSectionText(DataRefImpl Sec)471 bool ELFObjectFile<ELFT>::isSectionText(DataRefImpl Sec) const {
472   return toELFShdrIter(Sec)->sh_flags & ELF::SHF_EXECINSTR;
473 }
474 
475 template <class ELFT>
isSectionData(DataRefImpl Sec)476 bool ELFObjectFile<ELFT>::isSectionData(DataRefImpl Sec) const {
477   Elf_Shdr_Iter EShdr = toELFShdrIter(Sec);
478   return EShdr->sh_flags & (ELF::SHF_ALLOC | ELF::SHF_WRITE) &&
479          EShdr->sh_type == ELF::SHT_PROGBITS;
480 }
481 
482 template <class ELFT>
isSectionBSS(DataRefImpl Sec)483 bool ELFObjectFile<ELFT>::isSectionBSS(DataRefImpl Sec) const {
484   Elf_Shdr_Iter EShdr = toELFShdrIter(Sec);
485   return EShdr->sh_flags & (ELF::SHF_ALLOC | ELF::SHF_WRITE) &&
486          EShdr->sh_type == ELF::SHT_NOBITS;
487 }
488 
489 template <class ELFT>
isSectionVirtual(DataRefImpl Sec)490 bool ELFObjectFile<ELFT>::isSectionVirtual(DataRefImpl Sec) const {
491   return toELFShdrIter(Sec)->sh_type == ELF::SHT_NOBITS;
492 }
493 
494 template <class ELFT>
sectionContainsSymbol(DataRefImpl Sec,DataRefImpl Symb)495 bool ELFObjectFile<ELFT>::sectionContainsSymbol(DataRefImpl Sec,
496                                                 DataRefImpl Symb) const {
497   Elf_Sym_Iter ESym = toELFSymIter(Symb);
498 
499   uintX_t Index = ESym->st_shndx;
500   bool Reserved = Index >= ELF::SHN_LORESERVE && Index <= ELF::SHN_HIRESERVE;
501 
502   return !Reserved && (&*toELFShdrIter(Sec) == EF.getSection(ESym->st_shndx));
503 }
504 
505 template <class ELFT>
506 relocation_iterator
section_rel_begin(DataRefImpl Sec)507 ELFObjectFile<ELFT>::section_rel_begin(DataRefImpl Sec) const {
508   DataRefImpl RelData;
509   uintptr_t SHT = reinterpret_cast<uintptr_t>(EF.begin_sections().get());
510   RelData.d.a = (Sec.p - SHT) / EF.getHeader()->e_shentsize;
511   RelData.d.b = 0;
512   return relocation_iterator(RelocationRef(RelData, this));
513 }
514 
515 template <class ELFT>
516 relocation_iterator
section_rel_end(DataRefImpl Sec)517 ELFObjectFile<ELFT>::section_rel_end(DataRefImpl Sec) const {
518   DataRefImpl RelData;
519   uintptr_t SHT = reinterpret_cast<uintptr_t>(EF.begin_sections().get());
520   const Elf_Shdr *S = reinterpret_cast<const Elf_Shdr *>(Sec.p);
521   RelData.d.a = (Sec.p - SHT) / EF.getHeader()->e_shentsize;
522   if (S->sh_type != ELF::SHT_RELA && S->sh_type != ELF::SHT_REL)
523     RelData.d.b = 0;
524   else
525     RelData.d.b = S->sh_size / S->sh_entsize;
526 
527   return relocation_iterator(RelocationRef(RelData, this));
528 }
529 
530 template <class ELFT>
531 section_iterator
getRelocatedSection(DataRefImpl Sec)532 ELFObjectFile<ELFT>::getRelocatedSection(DataRefImpl Sec) const {
533   if (EF.getHeader()->e_type != ELF::ET_REL)
534     return section_end();
535 
536   Elf_Shdr_Iter EShdr = toELFShdrIter(Sec);
537   uintX_t Type = EShdr->sh_type;
538   if (Type != ELF::SHT_REL && Type != ELF::SHT_RELA)
539     return section_end();
540 
541   const Elf_Shdr *R = EF.getSection(EShdr->sh_info);
542   return section_iterator(SectionRef(toDRI(R), this));
543 }
544 
545 // Relocations
546 template <class ELFT>
moveRelocationNext(DataRefImpl & Rel)547 void ELFObjectFile<ELFT>::moveRelocationNext(DataRefImpl &Rel) const {
548   ++Rel.d.b;
549 }
550 
551 template <class ELFT>
552 symbol_iterator
getRelocationSymbol(DataRefImpl Rel)553 ELFObjectFile<ELFT>::getRelocationSymbol(DataRefImpl Rel) const {
554   uint32_t symbolIdx;
555   const Elf_Shdr *sec = getRelSection(Rel);
556   switch (sec->sh_type) {
557   default:
558     report_fatal_error("Invalid section type in Rel!");
559   case ELF::SHT_REL: {
560     symbolIdx = getRel(Rel)->getSymbol(EF.isMips64EL());
561     break;
562   }
563   case ELF::SHT_RELA: {
564     symbolIdx = getRela(Rel)->getSymbol(EF.isMips64EL());
565     break;
566   }
567   }
568   if (!symbolIdx)
569     return symbol_end();
570 
571   const Elf_Shdr *SymSec = EF.getSection(sec->sh_link);
572 
573   DataRefImpl SymbolData;
574   switch (SymSec->sh_type) {
575   default:
576     report_fatal_error("Invalid symbol table section type!");
577   case ELF::SHT_SYMTAB:
578     SymbolData = toDRI(EF.begin_symbols() + symbolIdx);
579     break;
580   case ELF::SHT_DYNSYM:
581     SymbolData = toDRI(EF.begin_dynamic_symbols() + symbolIdx);
582     break;
583   }
584 
585   return symbol_iterator(SymbolRef(SymbolData, this));
586 }
587 
588 template <class ELFT>
589 std::error_code
getRelocationAddress(DataRefImpl Rel,uint64_t & Result)590 ELFObjectFile<ELFT>::getRelocationAddress(DataRefImpl Rel,
591                                           uint64_t &Result) const {
592   uint64_t ROffset = getROffset(Rel);
593   const Elf_Ehdr *Header = EF.getHeader();
594 
595   if (Header->e_type == ELF::ET_REL) {
596     const Elf_Shdr *RelocationSec = getRelSection(Rel);
597     const Elf_Shdr *RelocatedSec = EF.getSection(RelocationSec->sh_info);
598     Result = ROffset + RelocatedSec->sh_addr;
599   } else {
600     Result = ROffset;
601   }
602 
603   return object_error::success;
604 }
605 
606 template <class ELFT>
607 std::error_code
getRelocationOffset(DataRefImpl Rel,uint64_t & Result)608 ELFObjectFile<ELFT>::getRelocationOffset(DataRefImpl Rel,
609                                          uint64_t &Result) const {
610   assert(EF.getHeader()->e_type == ELF::ET_REL &&
611          "Only relocatable object files have relocation offsets");
612   Result = getROffset(Rel);
613   return object_error::success;
614 }
615 
616 template <class ELFT>
getROffset(DataRefImpl Rel)617 uint64_t ELFObjectFile<ELFT>::getROffset(DataRefImpl Rel) const {
618   const Elf_Shdr *sec = getRelSection(Rel);
619   switch (sec->sh_type) {
620   default:
621     report_fatal_error("Invalid section type in Rel!");
622   case ELF::SHT_REL:
623     return getRel(Rel)->r_offset;
624   case ELF::SHT_RELA:
625     return getRela(Rel)->r_offset;
626   }
627 }
628 
629 template <class ELFT>
getRelocationType(DataRefImpl Rel,uint64_t & Result)630 std::error_code ELFObjectFile<ELFT>::getRelocationType(DataRefImpl Rel,
631                                                        uint64_t &Result) const {
632   const Elf_Shdr *sec = getRelSection(Rel);
633   switch (sec->sh_type) {
634   default:
635     report_fatal_error("Invalid section type in Rel!");
636   case ELF::SHT_REL: {
637     Result = getRel(Rel)->getType(EF.isMips64EL());
638     break;
639   }
640   case ELF::SHT_RELA: {
641     Result = getRela(Rel)->getType(EF.isMips64EL());
642     break;
643   }
644   }
645   return object_error::success;
646 }
647 
648 template <class ELFT>
getRelocationTypeName(uint32_t Type)649 StringRef ELFObjectFile<ELFT>::getRelocationTypeName(uint32_t Type) const {
650   return getELFRelocationTypeName(EF.getHeader()->e_machine, Type);
651 }
652 
653 template <class ELFT>
getRelocationTypeName(DataRefImpl Rel,SmallVectorImpl<char> & Result)654 std::error_code ELFObjectFile<ELFT>::getRelocationTypeName(
655     DataRefImpl Rel, SmallVectorImpl<char> &Result) const {
656   const Elf_Shdr *sec = getRelSection(Rel);
657   uint32_t type;
658   switch (sec->sh_type) {
659   default:
660     return object_error::parse_failed;
661   case ELF::SHT_REL: {
662     type = getRel(Rel)->getType(EF.isMips64EL());
663     break;
664   }
665   case ELF::SHT_RELA: {
666     type = getRela(Rel)->getType(EF.isMips64EL());
667     break;
668   }
669   }
670 
671   EF.getRelocationTypeName(type, Result);
672   return object_error::success;
673 }
674 
675 template <class ELFT>
676 std::error_code
getRelocationAddend(DataRefImpl Rel,int64_t & Result)677 ELFObjectFile<ELFT>::getRelocationAddend(DataRefImpl Rel,
678                                          int64_t &Result) const {
679   const Elf_Shdr *sec = getRelSection(Rel);
680   switch (sec->sh_type) {
681   default:
682     report_fatal_error("Invalid section type in Rel!");
683   case ELF::SHT_REL: {
684     Result = 0;
685     return object_error::success;
686   }
687   case ELF::SHT_RELA: {
688     Result = getRela(Rel)->r_addend;
689     return object_error::success;
690   }
691   }
692 }
693 
694 template <class ELFT>
getRelocationValueString(DataRefImpl Rel,SmallVectorImpl<char> & Result)695 std::error_code ELFObjectFile<ELFT>::getRelocationValueString(
696     DataRefImpl Rel, SmallVectorImpl<char> &Result) const {
697   const Elf_Shdr *sec = getRelSection(Rel);
698   uint8_t type;
699   StringRef res;
700   int64_t addend = 0;
701   uint16_t symbol_index = 0;
702   switch (sec->sh_type) {
703   default:
704     return object_error::parse_failed;
705   case ELF::SHT_REL: {
706     type = getRel(Rel)->getType(EF.isMips64EL());
707     symbol_index = getRel(Rel)->getSymbol(EF.isMips64EL());
708     // TODO: Read implicit addend from section data.
709     break;
710   }
711   case ELF::SHT_RELA: {
712     type = getRela(Rel)->getType(EF.isMips64EL());
713     symbol_index = getRela(Rel)->getSymbol(EF.isMips64EL());
714     addend = getRela(Rel)->r_addend;
715     break;
716   }
717   }
718   const Elf_Sym *symb =
719       EF.template getEntry<Elf_Sym>(sec->sh_link, symbol_index);
720   ErrorOr<StringRef> SymName =
721       EF.getSymbolName(EF.getSection(sec->sh_link), symb);
722   if (!SymName)
723     return SymName.getError();
724   switch (EF.getHeader()->e_machine) {
725   case ELF::EM_X86_64:
726     switch (type) {
727     case ELF::R_X86_64_PC8:
728     case ELF::R_X86_64_PC16:
729     case ELF::R_X86_64_PC32: {
730       std::string fmtbuf;
731       raw_string_ostream fmt(fmtbuf);
732       fmt << *SymName << (addend < 0 ? "" : "+") << addend << "-P";
733       fmt.flush();
734       Result.append(fmtbuf.begin(), fmtbuf.end());
735     } break;
736     case ELF::R_X86_64_8:
737     case ELF::R_X86_64_16:
738     case ELF::R_X86_64_32:
739     case ELF::R_X86_64_32S:
740     case ELF::R_X86_64_64: {
741       std::string fmtbuf;
742       raw_string_ostream fmt(fmtbuf);
743       fmt << *SymName << (addend < 0 ? "" : "+") << addend;
744       fmt.flush();
745       Result.append(fmtbuf.begin(), fmtbuf.end());
746     } break;
747     default:
748       res = "Unknown";
749     }
750     break;
751   case ELF::EM_AARCH64: {
752     std::string fmtbuf;
753     raw_string_ostream fmt(fmtbuf);
754     fmt << *SymName;
755     if (addend != 0)
756       fmt << (addend < 0 ? "" : "+") << addend;
757     fmt.flush();
758     Result.append(fmtbuf.begin(), fmtbuf.end());
759     break;
760   }
761   case ELF::EM_386:
762   case ELF::EM_ARM:
763   case ELF::EM_HEXAGON:
764   case ELF::EM_MIPS:
765     res = *SymName;
766     break;
767   default:
768     res = "Unknown";
769   }
770   if (Result.empty())
771     Result.append(res.begin(), res.end());
772   return object_error::success;
773 }
774 
775 template <class ELFT>
776 const typename ELFFile<ELFT>::Elf_Sym *
getSymbol(DataRefImpl Symb)777 ELFObjectFile<ELFT>::getSymbol(DataRefImpl Symb) const {
778   return &*toELFSymIter(Symb);
779 }
780 
781 template <class ELFT>
782 const typename ELFObjectFile<ELFT>::Elf_Rel *
getRel(DataRefImpl Rel)783 ELFObjectFile<ELFT>::getRel(DataRefImpl Rel) const {
784   return EF.template getEntry<Elf_Rel>(Rel.d.a, Rel.d.b);
785 }
786 
787 template <class ELFT>
788 const typename ELFObjectFile<ELFT>::Elf_Rela *
getRela(DataRefImpl Rela)789 ELFObjectFile<ELFT>::getRela(DataRefImpl Rela) const {
790   return EF.template getEntry<Elf_Rela>(Rela.d.a, Rela.d.b);
791 }
792 
793 template <class ELFT>
ELFObjectFile(MemoryBufferRef Object,std::error_code & EC)794 ELFObjectFile<ELFT>::ELFObjectFile(MemoryBufferRef Object, std::error_code &EC)
795     : ELFObjectFileBase(
796           getELFType(static_cast<endianness>(ELFT::TargetEndianness) ==
797                          support::little,
798                      ELFT::Is64Bits),
799           Object),
800       EF(Data.getBuffer(), EC) {}
801 
802 template <class ELFT>
symbol_begin_impl()803 basic_symbol_iterator ELFObjectFile<ELFT>::symbol_begin_impl() const {
804   return basic_symbol_iterator(SymbolRef(toDRI(EF.begin_symbols()), this));
805 }
806 
807 template <class ELFT>
symbol_end_impl()808 basic_symbol_iterator ELFObjectFile<ELFT>::symbol_end_impl() const {
809   return basic_symbol_iterator(SymbolRef(toDRI(EF.end_symbols()), this));
810 }
811 
812 template <class ELFT>
dynamic_symbol_begin()813 symbol_iterator ELFObjectFile<ELFT>::dynamic_symbol_begin() const {
814   return symbol_iterator(SymbolRef(toDRI(EF.begin_dynamic_symbols()), this));
815 }
816 
817 template <class ELFT>
dynamic_symbol_end()818 symbol_iterator ELFObjectFile<ELFT>::dynamic_symbol_end() const {
819   return symbol_iterator(SymbolRef(toDRI(EF.end_dynamic_symbols()), this));
820 }
821 
822 template <class ELFT>
section_begin()823 section_iterator ELFObjectFile<ELFT>::section_begin() const {
824   return section_iterator(SectionRef(toDRI(EF.begin_sections()), this));
825 }
826 
827 template <class ELFT>
section_end()828 section_iterator ELFObjectFile<ELFT>::section_end() const {
829   return section_iterator(SectionRef(toDRI(EF.end_sections()), this));
830 }
831 
832 template <class ELFT>
getLoadName()833 StringRef ELFObjectFile<ELFT>::getLoadName() const {
834   Elf_Dyn_Iter DI = EF.begin_dynamic_table();
835   Elf_Dyn_Iter DE = EF.end_dynamic_table();
836 
837   while (DI != DE && DI->getTag() != ELF::DT_SONAME)
838     ++DI;
839 
840   if (DI != DE)
841     return EF.getDynamicString(DI->getVal());
842   return "";
843 }
844 
845 template <class ELFT>
getBytesInAddress()846 uint8_t ELFObjectFile<ELFT>::getBytesInAddress() const {
847   return ELFT::Is64Bits ? 8 : 4;
848 }
849 
850 template <class ELFT>
getFileFormatName()851 StringRef ELFObjectFile<ELFT>::getFileFormatName() const {
852   bool IsLittleEndian = ELFT::TargetEndianness == support::little;
853   switch (EF.getHeader()->e_ident[ELF::EI_CLASS]) {
854   case ELF::ELFCLASS32:
855     switch (EF.getHeader()->e_machine) {
856     case ELF::EM_386:
857       return "ELF32-i386";
858     case ELF::EM_X86_64:
859       return "ELF32-x86-64";
860     case ELF::EM_ARM:
861       return (IsLittleEndian ? "ELF32-arm-little" : "ELF32-arm-big");
862     case ELF::EM_HEXAGON:
863       return "ELF32-hexagon";
864     case ELF::EM_MIPS:
865       return "ELF32-mips";
866     case ELF::EM_PPC:
867       return "ELF32-ppc";
868     case ELF::EM_SPARC:
869     case ELF::EM_SPARC32PLUS:
870       return "ELF32-sparc";
871     default:
872       return "ELF32-unknown";
873     }
874   case ELF::ELFCLASS64:
875     switch (EF.getHeader()->e_machine) {
876     case ELF::EM_386:
877       return "ELF64-i386";
878     case ELF::EM_X86_64:
879       return "ELF64-x86-64";
880     case ELF::EM_AARCH64:
881       return (IsLittleEndian ? "ELF64-aarch64-little" : "ELF64-aarch64-big");
882     case ELF::EM_PPC64:
883       return "ELF64-ppc64";
884     case ELF::EM_S390:
885       return "ELF64-s390";
886     case ELF::EM_SPARCV9:
887       return "ELF64-sparc";
888     case ELF::EM_MIPS:
889       return "ELF64-mips";
890     default:
891       return "ELF64-unknown";
892     }
893   default:
894     // FIXME: Proper error handling.
895     report_fatal_error("Invalid ELFCLASS!");
896   }
897 }
898 
899 template <class ELFT>
getArch()900 unsigned ELFObjectFile<ELFT>::getArch() const {
901   bool IsLittleEndian = ELFT::TargetEndianness == support::little;
902   switch (EF.getHeader()->e_machine) {
903   case ELF::EM_386:
904     return Triple::x86;
905   case ELF::EM_X86_64:
906     return Triple::x86_64;
907   case ELF::EM_AARCH64:
908     return Triple::aarch64;
909   case ELF::EM_ARM:
910     return Triple::arm;
911   case ELF::EM_HEXAGON:
912     return Triple::hexagon;
913   case ELF::EM_MIPS:
914     switch (EF.getHeader()->e_ident[ELF::EI_CLASS]) {
915     case ELF::ELFCLASS32:
916       return IsLittleEndian ? Triple::mipsel : Triple::mips;
917     case ELF::ELFCLASS64:
918       return IsLittleEndian ? Triple::mips64el : Triple::mips64;
919     default:
920       report_fatal_error("Invalid ELFCLASS!");
921     }
922   case ELF::EM_PPC:
923     return Triple::ppc;
924   case ELF::EM_PPC64:
925     return IsLittleEndian ? Triple::ppc64le : Triple::ppc64;
926   case ELF::EM_S390:
927     return Triple::systemz;
928 
929   case ELF::EM_SPARC:
930   case ELF::EM_SPARC32PLUS:
931     return Triple::sparc;
932   case ELF::EM_SPARCV9:
933     return Triple::sparcv9;
934 
935   default:
936     return Triple::UnknownArch;
937   }
938 }
939 
940 template <class ELFT>
941 std::pair<symbol_iterator, symbol_iterator>
getELFDynamicSymbolIterators()942 ELFObjectFile<ELFT>::getELFDynamicSymbolIterators() const {
943   return std::make_pair(dynamic_symbol_begin(), dynamic_symbol_end());
944 }
945 
isRelocatableObject()946 template <class ELFT> bool ELFObjectFile<ELFT>::isRelocatableObject() const {
947   return EF.getHeader()->e_type == ELF::ET_REL;
948 }
949 
getELFRelocationAddend(const RelocationRef R,int64_t & Addend)950 inline std::error_code getELFRelocationAddend(const RelocationRef R,
951                                               int64_t &Addend) {
952   const ObjectFile *Obj = R.getObjectFile();
953   DataRefImpl DRI = R.getRawDataRefImpl();
954   return cast<ELFObjectFileBase>(Obj)->getRelocationAddend(DRI, Addend);
955 }
956 
957 inline std::pair<symbol_iterator, symbol_iterator>
getELFDynamicSymbolIterators(const SymbolicFile * Obj)958 getELFDynamicSymbolIterators(const SymbolicFile *Obj) {
959   return cast<ELFObjectFileBase>(Obj)->getELFDynamicSymbolIterators();
960 }
961 
GetELFSymbolVersion(const ObjectFile * Obj,const SymbolRef & Sym,StringRef & Version,bool & IsDefault)962 inline std::error_code GetELFSymbolVersion(const ObjectFile *Obj,
963                                            const SymbolRef &Sym,
964                                            StringRef &Version,
965                                            bool &IsDefault) {
966   return cast<ELFObjectFileBase>(Obj)
967       ->getSymbolVersion(Sym, Version, IsDefault);
968 }
969 }
970 }
971 
972 #endif
973