COFFObjectFile.cpp revision dce4a407a24b04eebc6a376f8e62b41aaa7b071f 
1//===- COFFObjectFile.cpp - COFF 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 COFFObjectFile class.
11//
12//===----------------------------------------------------------------------===//
13
14#include "llvm/Object/COFF.h"
15#include "llvm/ADT/ArrayRef.h"
16#include "llvm/ADT/SmallString.h"
17#include "llvm/ADT/StringSwitch.h"
18#include "llvm/ADT/Triple.h"
19#include "llvm/Support/COFF.h"
20#include "llvm/Support/Debug.h"
21#include "llvm/Support/raw_ostream.h"
22#include <cctype>
23#include <limits>
24
25using namespace llvm;
26using namespace object;
27
28using support::ulittle8_t;
29using support::ulittle16_t;
30using support::ulittle32_t;
31using support::little16_t;
32
33// Returns false if size is greater than the buffer size. And sets ec.
34static bool checkSize(const MemoryBuffer *M, error_code &EC, uint64_t Size) {
35  if (M->getBufferSize() < Size) {
36    EC = object_error::unexpected_eof;
37    return false;
38  }
39  return true;
40}
41
42// Sets Obj unless any bytes in [addr, addr + size) fall outsize of m.
43// Returns unexpected_eof if error.
44template<typename T>
45static error_code getObject(const T *&Obj, const MemoryBuffer *M,
46                            const uint8_t *Ptr, const size_t Size = sizeof(T)) {
47  uintptr_t Addr = uintptr_t(Ptr);
48  if (Addr + Size < Addr ||
49      Addr + Size < Size ||
50      Addr + Size > uintptr_t(M->getBufferEnd())) {
51    return object_error::unexpected_eof;
52  }
53  Obj = reinterpret_cast<const T *>(Addr);
54  return object_error::success;
55}
56
57// Decode a string table entry in base 64 (//AAAAAA). Expects \arg Str without
58// prefixed slashes.
59static bool decodeBase64StringEntry(StringRef Str, uint32_t &Result) {
60  assert(Str.size() <= 6 && "String too long, possible overflow.");
61  if (Str.size() > 6)
62    return true;
63
64  uint64_t Value = 0;
65  while (!Str.empty()) {
66    unsigned CharVal;
67    if (Str[0] >= 'A' && Str[0] <= 'Z') // 0..25
68      CharVal = Str[0] - 'A';
69    else if (Str[0] >= 'a' && Str[0] <= 'z') // 26..51
70      CharVal = Str[0] - 'a' + 26;
71    else if (Str[0] >= '0' && Str[0] <= '9') // 52..61
72      CharVal = Str[0] - '0' + 52;
73    else if (Str[0] == '+') // 62
74      CharVal = 62;
75    else if (Str[0] == '/') // 63
76      CharVal = 63;
77    else
78      return true;
79
80    Value = (Value * 64) + CharVal;
81    Str = Str.substr(1);
82  }
83
84  if (Value > std::numeric_limits<uint32_t>::max())
85    return true;
86
87  Result = static_cast<uint32_t>(Value);
88  return false;
89}
90
91const coff_symbol *COFFObjectFile::toSymb(DataRefImpl Ref) const {
92  const coff_symbol *Addr = reinterpret_cast<const coff_symbol*>(Ref.p);
93
94# ifndef NDEBUG
95  // Verify that the symbol points to a valid entry in the symbol table.
96  uintptr_t Offset = uintptr_t(Addr) - uintptr_t(base());
97  if (Offset < COFFHeader->PointerToSymbolTable
98      || Offset >= COFFHeader->PointerToSymbolTable
99         + (COFFHeader->NumberOfSymbols * sizeof(coff_symbol)))
100    report_fatal_error("Symbol was outside of symbol table.");
101
102  assert((Offset - COFFHeader->PointerToSymbolTable) % sizeof(coff_symbol)
103         == 0 && "Symbol did not point to the beginning of a symbol");
104# endif
105
106  return Addr;
107}
108
109const coff_section *COFFObjectFile::toSec(DataRefImpl Ref) const {
110  const coff_section *Addr = reinterpret_cast<const coff_section*>(Ref.p);
111
112# ifndef NDEBUG
113  // Verify that the section points to a valid entry in the section table.
114  if (Addr < SectionTable
115      || Addr >= (SectionTable + COFFHeader->NumberOfSections))
116    report_fatal_error("Section was outside of section table.");
117
118  uintptr_t Offset = uintptr_t(Addr) - uintptr_t(SectionTable);
119  assert(Offset % sizeof(coff_section) == 0 &&
120         "Section did not point to the beginning of a section");
121# endif
122
123  return Addr;
124}
125
126void COFFObjectFile::moveSymbolNext(DataRefImpl &Ref) const {
127  const coff_symbol *Symb = toSymb(Ref);
128  Symb += 1 + Symb->NumberOfAuxSymbols;
129  Ref.p = reinterpret_cast<uintptr_t>(Symb);
130}
131
132error_code COFFObjectFile::getSymbolName(DataRefImpl Ref,
133                                         StringRef &Result) const {
134  const coff_symbol *Symb = toSymb(Ref);
135  return getSymbolName(Symb, Result);
136}
137
138error_code COFFObjectFile::getSymbolAddress(DataRefImpl Ref,
139                                            uint64_t &Result) const {
140  const coff_symbol *Symb = toSymb(Ref);
141  const coff_section *Section = nullptr;
142  if (error_code EC = getSection(Symb->SectionNumber, Section))
143    return EC;
144
145  if (Symb->SectionNumber == COFF::IMAGE_SYM_UNDEFINED)
146    Result = UnknownAddressOrSize;
147  else if (Section)
148    Result = Section->VirtualAddress + Symb->Value;
149  else
150    Result = Symb->Value;
151  return object_error::success;
152}
153
154error_code COFFObjectFile::getSymbolType(DataRefImpl Ref,
155                                         SymbolRef::Type &Result) const {
156  const coff_symbol *Symb = toSymb(Ref);
157  Result = SymbolRef::ST_Other;
158  if (Symb->StorageClass == COFF::IMAGE_SYM_CLASS_EXTERNAL &&
159      Symb->SectionNumber == COFF::IMAGE_SYM_UNDEFINED) {
160    Result = SymbolRef::ST_Unknown;
161  } else if (Symb->isFunctionDefinition()) {
162    Result = SymbolRef::ST_Function;
163  } else {
164    uint32_t Characteristics = 0;
165    if (!COFF::isReservedSectionNumber(Symb->SectionNumber)) {
166      const coff_section *Section = nullptr;
167      if (error_code EC = getSection(Symb->SectionNumber, Section))
168        return EC;
169      Characteristics = Section->Characteristics;
170    }
171    if (Characteristics & COFF::IMAGE_SCN_MEM_READ &&
172        ~Characteristics & COFF::IMAGE_SCN_MEM_WRITE) // Read only.
173      Result = SymbolRef::ST_Data;
174  }
175  return object_error::success;
176}
177
178uint32_t COFFObjectFile::getSymbolFlags(DataRefImpl Ref) const {
179  const coff_symbol *Symb = toSymb(Ref);
180  uint32_t Result = SymbolRef::SF_None;
181
182  // TODO: Correctly set SF_FormatSpecific, SF_Common
183
184  if (Symb->SectionNumber == COFF::IMAGE_SYM_UNDEFINED) {
185    if (Symb->Value == 0)
186      Result |= SymbolRef::SF_Undefined;
187    else
188      Result |= SymbolRef::SF_Common;
189  }
190
191
192  // TODO: This are certainly too restrictive.
193  if (Symb->StorageClass == COFF::IMAGE_SYM_CLASS_EXTERNAL)
194    Result |= SymbolRef::SF_Global;
195
196  if (Symb->StorageClass == COFF::IMAGE_SYM_CLASS_WEAK_EXTERNAL)
197    Result |= SymbolRef::SF_Weak;
198
199  if (Symb->SectionNumber == COFF::IMAGE_SYM_ABSOLUTE)
200    Result |= SymbolRef::SF_Absolute;
201
202  return Result;
203}
204
205error_code COFFObjectFile::getSymbolSize(DataRefImpl Ref,
206                                         uint64_t &Result) const {
207  // FIXME: Return the correct size. This requires looking at all the symbols
208  //        in the same section as this symbol, and looking for either the next
209  //        symbol, or the end of the section.
210  const coff_symbol *Symb = toSymb(Ref);
211  const coff_section *Section = nullptr;
212  if (error_code EC = getSection(Symb->SectionNumber, Section))
213    return EC;
214
215  if (Symb->SectionNumber == COFF::IMAGE_SYM_UNDEFINED)
216    Result = UnknownAddressOrSize;
217  else if (Section)
218    Result = Section->SizeOfRawData - Symb->Value;
219  else
220    Result = 0;
221  return object_error::success;
222}
223
224error_code COFFObjectFile::getSymbolSection(DataRefImpl Ref,
225                                            section_iterator &Result) const {
226  const coff_symbol *Symb = toSymb(Ref);
227  if (COFF::isReservedSectionNumber(Symb->SectionNumber)) {
228    Result = section_end();
229  } else {
230    const coff_section *Sec = nullptr;
231    if (error_code EC = getSection(Symb->SectionNumber, Sec)) return EC;
232    DataRefImpl Ref;
233    Ref.p = reinterpret_cast<uintptr_t>(Sec);
234    Result = section_iterator(SectionRef(Ref, this));
235  }
236  return object_error::success;
237}
238
239void COFFObjectFile::moveSectionNext(DataRefImpl &Ref) const {
240  const coff_section *Sec = toSec(Ref);
241  Sec += 1;
242  Ref.p = reinterpret_cast<uintptr_t>(Sec);
243}
244
245error_code COFFObjectFile::getSectionName(DataRefImpl Ref,
246                                          StringRef &Result) const {
247  const coff_section *Sec = toSec(Ref);
248  return getSectionName(Sec, Result);
249}
250
251error_code COFFObjectFile::getSectionAddress(DataRefImpl Ref,
252                                             uint64_t &Result) const {
253  const coff_section *Sec = toSec(Ref);
254  Result = Sec->VirtualAddress;
255  return object_error::success;
256}
257
258error_code COFFObjectFile::getSectionSize(DataRefImpl Ref,
259                                          uint64_t &Result) const {
260  const coff_section *Sec = toSec(Ref);
261  Result = Sec->SizeOfRawData;
262  return object_error::success;
263}
264
265error_code COFFObjectFile::getSectionContents(DataRefImpl Ref,
266                                              StringRef &Result) const {
267  const coff_section *Sec = toSec(Ref);
268  ArrayRef<uint8_t> Res;
269  error_code EC = getSectionContents(Sec, Res);
270  Result = StringRef(reinterpret_cast<const char*>(Res.data()), Res.size());
271  return EC;
272}
273
274error_code COFFObjectFile::getSectionAlignment(DataRefImpl Ref,
275                                               uint64_t &Res) const {
276  const coff_section *Sec = toSec(Ref);
277  if (!Sec)
278    return object_error::parse_failed;
279  Res = uint64_t(1) << (((Sec->Characteristics & 0x00F00000) >> 20) - 1);
280  return object_error::success;
281}
282
283error_code COFFObjectFile::isSectionText(DataRefImpl Ref,
284                                         bool &Result) const {
285  const coff_section *Sec = toSec(Ref);
286  Result = Sec->Characteristics & COFF::IMAGE_SCN_CNT_CODE;
287  return object_error::success;
288}
289
290error_code COFFObjectFile::isSectionData(DataRefImpl Ref,
291                                         bool &Result) const {
292  const coff_section *Sec = toSec(Ref);
293  Result = Sec->Characteristics & COFF::IMAGE_SCN_CNT_INITIALIZED_DATA;
294  return object_error::success;
295}
296
297error_code COFFObjectFile::isSectionBSS(DataRefImpl Ref,
298                                        bool &Result) const {
299  const coff_section *Sec = toSec(Ref);
300  Result = Sec->Characteristics & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA;
301  return object_error::success;
302}
303
304error_code COFFObjectFile::isSectionRequiredForExecution(DataRefImpl Ref,
305                                                         bool &Result) const {
306  // FIXME: Unimplemented
307  Result = true;
308  return object_error::success;
309}
310
311error_code COFFObjectFile::isSectionVirtual(DataRefImpl Ref,
312                                           bool &Result) const {
313  const coff_section *Sec = toSec(Ref);
314  Result = Sec->Characteristics & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA;
315  return object_error::success;
316}
317
318error_code COFFObjectFile::isSectionZeroInit(DataRefImpl Ref,
319                                             bool &Result) const {
320  // FIXME: Unimplemented.
321  Result = false;
322  return object_error::success;
323}
324
325error_code COFFObjectFile::isSectionReadOnlyData(DataRefImpl Ref,
326                                                bool &Result) const {
327  // FIXME: Unimplemented.
328  Result = false;
329  return object_error::success;
330}
331
332error_code COFFObjectFile::sectionContainsSymbol(DataRefImpl SecRef,
333                                                 DataRefImpl SymbRef,
334                                                 bool &Result) const {
335  const coff_section *Sec = toSec(SecRef);
336  const coff_symbol *Symb = toSymb(SymbRef);
337  const coff_section *SymbSec = nullptr;
338  if (error_code EC = getSection(Symb->SectionNumber, SymbSec)) return EC;
339  if (SymbSec == Sec)
340    Result = true;
341  else
342    Result = false;
343  return object_error::success;
344}
345
346relocation_iterator COFFObjectFile::section_rel_begin(DataRefImpl Ref) const {
347  const coff_section *Sec = toSec(Ref);
348  DataRefImpl Ret;
349  if (Sec->NumberOfRelocations == 0) {
350    Ret.p = 0;
351  } else {
352    auto begin = reinterpret_cast<const coff_relocation*>(
353        base() + Sec->PointerToRelocations);
354    if (Sec->hasExtendedRelocations()) {
355      // Skip the first relocation entry repurposed to store the number of
356      // relocations.
357      begin++;
358    }
359    Ret.p = reinterpret_cast<uintptr_t>(begin);
360  }
361  return relocation_iterator(RelocationRef(Ret, this));
362}
363
364static uint32_t getNumberOfRelocations(const coff_section *Sec,
365                                       const uint8_t *base) {
366  // The field for the number of relocations in COFF section table is only
367  // 16-bit wide. If a section has more than 65535 relocations, 0xFFFF is set to
368  // NumberOfRelocations field, and the actual relocation count is stored in the
369  // VirtualAddress field in the first relocation entry.
370  if (Sec->hasExtendedRelocations()) {
371    auto *FirstReloc = reinterpret_cast<const coff_relocation*>(
372        base + Sec->PointerToRelocations);
373    return FirstReloc->VirtualAddress;
374  }
375  return Sec->NumberOfRelocations;
376}
377
378relocation_iterator COFFObjectFile::section_rel_end(DataRefImpl Ref) const {
379  const coff_section *Sec = toSec(Ref);
380  DataRefImpl Ret;
381  if (Sec->NumberOfRelocations == 0) {
382    Ret.p = 0;
383  } else {
384    auto begin = reinterpret_cast<const coff_relocation*>(
385        base() + Sec->PointerToRelocations);
386    uint32_t NumReloc = getNumberOfRelocations(Sec, base());
387    Ret.p = reinterpret_cast<uintptr_t>(begin + NumReloc);
388  }
389  return relocation_iterator(RelocationRef(Ret, this));
390}
391
392// Initialize the pointer to the symbol table.
393error_code COFFObjectFile::initSymbolTablePtr() {
394  if (error_code EC = getObject(
395          SymbolTable, Data, base() + COFFHeader->PointerToSymbolTable,
396          COFFHeader->NumberOfSymbols * sizeof(coff_symbol)))
397    return EC;
398
399  // Find string table. The first four byte of the string table contains the
400  // total size of the string table, including the size field itself. If the
401  // string table is empty, the value of the first four byte would be 4.
402  const uint8_t *StringTableAddr =
403      base() + COFFHeader->PointerToSymbolTable +
404      COFFHeader->NumberOfSymbols * sizeof(coff_symbol);
405  const ulittle32_t *StringTableSizePtr;
406  if (error_code EC = getObject(StringTableSizePtr, Data, StringTableAddr))
407    return EC;
408  StringTableSize = *StringTableSizePtr;
409  if (error_code EC =
410      getObject(StringTable, Data, StringTableAddr, StringTableSize))
411    return EC;
412
413  // Treat table sizes < 4 as empty because contrary to the PECOFF spec, some
414  // tools like cvtres write a size of 0 for an empty table instead of 4.
415  if (StringTableSize < 4)
416      StringTableSize = 4;
417
418  // Check that the string table is null terminated if has any in it.
419  if (StringTableSize > 4 && StringTable[StringTableSize - 1] != 0)
420    return  object_error::parse_failed;
421  return object_error::success;
422}
423
424// Returns the file offset for the given VA.
425error_code COFFObjectFile::getVaPtr(uint64_t Addr, uintptr_t &Res) const {
426  uint64_t ImageBase = PE32Header ? (uint64_t)PE32Header->ImageBase
427                                  : (uint64_t)PE32PlusHeader->ImageBase;
428  uint64_t Rva = Addr - ImageBase;
429  assert(Rva <= UINT32_MAX);
430  return getRvaPtr((uint32_t)Rva, Res);
431}
432
433// Returns the file offset for the given RVA.
434error_code COFFObjectFile::getRvaPtr(uint32_t Addr, uintptr_t &Res) const {
435  for (const SectionRef &S : sections()) {
436    const coff_section *Section = getCOFFSection(S);
437    uint32_t SectionStart = Section->VirtualAddress;
438    uint32_t SectionEnd = Section->VirtualAddress + Section->VirtualSize;
439    if (SectionStart <= Addr && Addr < SectionEnd) {
440      uint32_t Offset = Addr - SectionStart;
441      Res = uintptr_t(base()) + Section->PointerToRawData + Offset;
442      return object_error::success;
443    }
444  }
445  return object_error::parse_failed;
446}
447
448// Returns hint and name fields, assuming \p Rva is pointing to a Hint/Name
449// table entry.
450error_code COFFObjectFile::
451getHintName(uint32_t Rva, uint16_t &Hint, StringRef &Name) const {
452  uintptr_t IntPtr = 0;
453  if (error_code EC = getRvaPtr(Rva, IntPtr))
454    return EC;
455  const uint8_t *Ptr = reinterpret_cast<const uint8_t *>(IntPtr);
456  Hint = *reinterpret_cast<const ulittle16_t *>(Ptr);
457  Name = StringRef(reinterpret_cast<const char *>(Ptr + 2));
458  return object_error::success;
459}
460
461// Find the import table.
462error_code COFFObjectFile::initImportTablePtr() {
463  // First, we get the RVA of the import table. If the file lacks a pointer to
464  // the import table, do nothing.
465  const data_directory *DataEntry;
466  if (getDataDirectory(COFF::IMPORT_TABLE, DataEntry))
467    return object_error::success;
468
469  // Do nothing if the pointer to import table is NULL.
470  if (DataEntry->RelativeVirtualAddress == 0)
471    return object_error::success;
472
473  uint32_t ImportTableRva = DataEntry->RelativeVirtualAddress;
474  NumberOfImportDirectory = DataEntry->Size /
475      sizeof(import_directory_table_entry);
476
477  // Find the section that contains the RVA. This is needed because the RVA is
478  // the import table's memory address which is different from its file offset.
479  uintptr_t IntPtr = 0;
480  if (error_code EC = getRvaPtr(ImportTableRva, IntPtr))
481    return EC;
482  ImportDirectory = reinterpret_cast<
483      const import_directory_table_entry *>(IntPtr);
484  return object_error::success;
485}
486
487// Find the export table.
488error_code COFFObjectFile::initExportTablePtr() {
489  // First, we get the RVA of the export table. If the file lacks a pointer to
490  // the export table, do nothing.
491  const data_directory *DataEntry;
492  if (getDataDirectory(COFF::EXPORT_TABLE, DataEntry))
493    return object_error::success;
494
495  // Do nothing if the pointer to export table is NULL.
496  if (DataEntry->RelativeVirtualAddress == 0)
497    return object_error::success;
498
499  uint32_t ExportTableRva = DataEntry->RelativeVirtualAddress;
500  uintptr_t IntPtr = 0;
501  if (error_code EC = getRvaPtr(ExportTableRva, IntPtr))
502    return EC;
503  ExportDirectory =
504      reinterpret_cast<const export_directory_table_entry *>(IntPtr);
505  return object_error::success;
506}
507
508COFFObjectFile::COFFObjectFile(MemoryBuffer *Object, error_code &EC,
509                               bool BufferOwned)
510    : ObjectFile(Binary::ID_COFF, Object, BufferOwned), COFFHeader(nullptr),
511      PE32Header(nullptr), PE32PlusHeader(nullptr), DataDirectory(nullptr),
512      SectionTable(nullptr), SymbolTable(nullptr), StringTable(nullptr),
513      StringTableSize(0), ImportDirectory(nullptr), NumberOfImportDirectory(0),
514      ExportDirectory(nullptr) {
515  // Check that we at least have enough room for a header.
516  if (!checkSize(Data, EC, sizeof(coff_file_header))) return;
517
518  // The current location in the file where we are looking at.
519  uint64_t CurPtr = 0;
520
521  // PE header is optional and is present only in executables. If it exists,
522  // it is placed right after COFF header.
523  bool HasPEHeader = false;
524
525  // Check if this is a PE/COFF file.
526  if (base()[0] == 0x4d && base()[1] == 0x5a) {
527    // PE/COFF, seek through MS-DOS compatibility stub and 4-byte
528    // PE signature to find 'normal' COFF header.
529    if (!checkSize(Data, EC, 0x3c + 8)) return;
530    CurPtr = *reinterpret_cast<const ulittle16_t *>(base() + 0x3c);
531    // Check the PE magic bytes. ("PE\0\0")
532    if (std::memcmp(base() + CurPtr, "PE\0\0", 4) != 0) {
533      EC = object_error::parse_failed;
534      return;
535    }
536    CurPtr += 4; // Skip the PE magic bytes.
537    HasPEHeader = true;
538  }
539
540  if ((EC = getObject(COFFHeader, Data, base() + CurPtr)))
541    return;
542  CurPtr += sizeof(coff_file_header);
543
544  if (HasPEHeader) {
545    const pe32_header *Header;
546    if ((EC = getObject(Header, Data, base() + CurPtr)))
547      return;
548
549    const uint8_t *DataDirAddr;
550    uint64_t DataDirSize;
551    if (Header->Magic == 0x10b) {
552      PE32Header = Header;
553      DataDirAddr = base() + CurPtr + sizeof(pe32_header);
554      DataDirSize = sizeof(data_directory) * PE32Header->NumberOfRvaAndSize;
555    } else if (Header->Magic == 0x20b) {
556      PE32PlusHeader = reinterpret_cast<const pe32plus_header *>(Header);
557      DataDirAddr = base() + CurPtr + sizeof(pe32plus_header);
558      DataDirSize = sizeof(data_directory) * PE32PlusHeader->NumberOfRvaAndSize;
559    } else {
560      // It's neither PE32 nor PE32+.
561      EC = object_error::parse_failed;
562      return;
563    }
564    if ((EC = getObject(DataDirectory, Data, DataDirAddr, DataDirSize)))
565      return;
566    CurPtr += COFFHeader->SizeOfOptionalHeader;
567  }
568
569  if (COFFHeader->isImportLibrary())
570    return;
571
572  if ((EC = getObject(SectionTable, Data, base() + CurPtr,
573                      COFFHeader->NumberOfSections * sizeof(coff_section))))
574    return;
575
576  // Initialize the pointer to the symbol table.
577  if (COFFHeader->PointerToSymbolTable != 0)
578    if ((EC = initSymbolTablePtr()))
579      return;
580
581  // Initialize the pointer to the beginning of the import table.
582  if ((EC = initImportTablePtr()))
583    return;
584
585  // Initialize the pointer to the export table.
586  if ((EC = initExportTablePtr()))
587    return;
588
589  EC = object_error::success;
590}
591
592basic_symbol_iterator COFFObjectFile::symbol_begin_impl() const {
593  DataRefImpl Ret;
594  Ret.p = reinterpret_cast<uintptr_t>(SymbolTable);
595  return basic_symbol_iterator(SymbolRef(Ret, this));
596}
597
598basic_symbol_iterator COFFObjectFile::symbol_end_impl() const {
599  // The symbol table ends where the string table begins.
600  DataRefImpl Ret;
601  Ret.p = reinterpret_cast<uintptr_t>(StringTable);
602  return basic_symbol_iterator(SymbolRef(Ret, this));
603}
604
605library_iterator COFFObjectFile::needed_library_begin() const {
606  // TODO: implement
607  report_fatal_error("Libraries needed unimplemented in COFFObjectFile");
608}
609
610library_iterator COFFObjectFile::needed_library_end() const {
611  // TODO: implement
612  report_fatal_error("Libraries needed unimplemented in COFFObjectFile");
613}
614
615StringRef COFFObjectFile::getLoadName() const {
616  // COFF does not have this field.
617  return "";
618}
619
620import_directory_iterator COFFObjectFile::import_directory_begin() const {
621  return import_directory_iterator(
622      ImportDirectoryEntryRef(ImportDirectory, 0, this));
623}
624
625import_directory_iterator COFFObjectFile::import_directory_end() const {
626  return import_directory_iterator(
627      ImportDirectoryEntryRef(ImportDirectory, NumberOfImportDirectory, this));
628}
629
630export_directory_iterator COFFObjectFile::export_directory_begin() const {
631  return export_directory_iterator(
632      ExportDirectoryEntryRef(ExportDirectory, 0, this));
633}
634
635export_directory_iterator COFFObjectFile::export_directory_end() const {
636  if (!ExportDirectory)
637    return export_directory_iterator(ExportDirectoryEntryRef(nullptr, 0, this));
638  ExportDirectoryEntryRef Ref(ExportDirectory,
639                              ExportDirectory->AddressTableEntries, this);
640  return export_directory_iterator(Ref);
641}
642
643section_iterator COFFObjectFile::section_begin() const {
644  DataRefImpl Ret;
645  Ret.p = reinterpret_cast<uintptr_t>(SectionTable);
646  return section_iterator(SectionRef(Ret, this));
647}
648
649section_iterator COFFObjectFile::section_end() const {
650  DataRefImpl Ret;
651  int NumSections = COFFHeader->isImportLibrary()
652      ? 0 : COFFHeader->NumberOfSections;
653  Ret.p = reinterpret_cast<uintptr_t>(SectionTable + NumSections);
654  return section_iterator(SectionRef(Ret, this));
655}
656
657uint8_t COFFObjectFile::getBytesInAddress() const {
658  return getArch() == Triple::x86_64 ? 8 : 4;
659}
660
661StringRef COFFObjectFile::getFileFormatName() const {
662  switch(COFFHeader->Machine) {
663  case COFF::IMAGE_FILE_MACHINE_I386:
664    return "COFF-i386";
665  case COFF::IMAGE_FILE_MACHINE_AMD64:
666    return "COFF-x86-64";
667  case COFF::IMAGE_FILE_MACHINE_ARMNT:
668    return "COFF-ARM";
669  default:
670    return "COFF-<unknown arch>";
671  }
672}
673
674unsigned COFFObjectFile::getArch() const {
675  switch(COFFHeader->Machine) {
676  case COFF::IMAGE_FILE_MACHINE_I386:
677    return Triple::x86;
678  case COFF::IMAGE_FILE_MACHINE_AMD64:
679    return Triple::x86_64;
680  case COFF::IMAGE_FILE_MACHINE_ARMNT:
681    return Triple::thumb;
682  default:
683    return Triple::UnknownArch;
684  }
685}
686
687// This method is kept here because lld uses this. As soon as we make
688// lld to use getCOFFHeader, this method will be removed.
689error_code COFFObjectFile::getHeader(const coff_file_header *&Res) const {
690  return getCOFFHeader(Res);
691}
692
693error_code COFFObjectFile::getCOFFHeader(const coff_file_header *&Res) const {
694  Res = COFFHeader;
695  return object_error::success;
696}
697
698error_code COFFObjectFile::getPE32Header(const pe32_header *&Res) const {
699  Res = PE32Header;
700  return object_error::success;
701}
702
703error_code
704COFFObjectFile::getPE32PlusHeader(const pe32plus_header *&Res) const {
705  Res = PE32PlusHeader;
706  return object_error::success;
707}
708
709error_code COFFObjectFile::getDataDirectory(uint32_t Index,
710                                            const data_directory *&Res) const {
711  // Error if if there's no data directory or the index is out of range.
712  if (!DataDirectory)
713    return object_error::parse_failed;
714  assert(PE32Header || PE32PlusHeader);
715  uint32_t NumEnt = PE32Header ? PE32Header->NumberOfRvaAndSize
716                               : PE32PlusHeader->NumberOfRvaAndSize;
717  if (Index > NumEnt)
718    return object_error::parse_failed;
719  Res = &DataDirectory[Index];
720  return object_error::success;
721}
722
723error_code COFFObjectFile::getSection(int32_t Index,
724                                      const coff_section *&Result) const {
725  // Check for special index values.
726  if (COFF::isReservedSectionNumber(Index))
727    Result = nullptr;
728  else if (Index > 0 && Index <= COFFHeader->NumberOfSections)
729    // We already verified the section table data, so no need to check again.
730    Result = SectionTable + (Index - 1);
731  else
732    return object_error::parse_failed;
733  return object_error::success;
734}
735
736error_code COFFObjectFile::getString(uint32_t Offset,
737                                     StringRef &Result) const {
738  if (StringTableSize <= 4)
739    // Tried to get a string from an empty string table.
740    return object_error::parse_failed;
741  if (Offset >= StringTableSize)
742    return object_error::unexpected_eof;
743  Result = StringRef(StringTable + Offset);
744  return object_error::success;
745}
746
747error_code COFFObjectFile::getSymbol(uint32_t Index,
748                                     const coff_symbol *&Result) const {
749  if (Index < COFFHeader->NumberOfSymbols)
750    Result = SymbolTable + Index;
751  else
752    return object_error::parse_failed;
753  return object_error::success;
754}
755
756error_code COFFObjectFile::getSymbolName(const coff_symbol *Symbol,
757                                         StringRef &Res) const {
758  // Check for string table entry. First 4 bytes are 0.
759  if (Symbol->Name.Offset.Zeroes == 0) {
760    uint32_t Offset = Symbol->Name.Offset.Offset;
761    if (error_code EC = getString(Offset, Res))
762      return EC;
763    return object_error::success;
764  }
765
766  if (Symbol->Name.ShortName[7] == 0)
767    // Null terminated, let ::strlen figure out the length.
768    Res = StringRef(Symbol->Name.ShortName);
769  else
770    // Not null terminated, use all 8 bytes.
771    Res = StringRef(Symbol->Name.ShortName, 8);
772  return object_error::success;
773}
774
775ArrayRef<uint8_t> COFFObjectFile::getSymbolAuxData(
776                                  const coff_symbol *Symbol) const {
777  const uint8_t *Aux = nullptr;
778
779  if (Symbol->NumberOfAuxSymbols > 0) {
780  // AUX data comes immediately after the symbol in COFF
781    Aux = reinterpret_cast<const uint8_t *>(Symbol + 1);
782# ifndef NDEBUG
783    // Verify that the Aux symbol points to a valid entry in the symbol table.
784    uintptr_t Offset = uintptr_t(Aux) - uintptr_t(base());
785    if (Offset < COFFHeader->PointerToSymbolTable
786        || Offset >= COFFHeader->PointerToSymbolTable
787           + (COFFHeader->NumberOfSymbols * sizeof(coff_symbol)))
788      report_fatal_error("Aux Symbol data was outside of symbol table.");
789
790    assert((Offset - COFFHeader->PointerToSymbolTable) % sizeof(coff_symbol)
791         == 0 && "Aux Symbol data did not point to the beginning of a symbol");
792# endif
793  }
794  return ArrayRef<uint8_t>(Aux,
795                           Symbol->NumberOfAuxSymbols * sizeof(coff_symbol));
796}
797
798error_code COFFObjectFile::getSectionName(const coff_section *Sec,
799                                          StringRef &Res) const {
800  StringRef Name;
801  if (Sec->Name[7] == 0)
802    // Null terminated, let ::strlen figure out the length.
803    Name = Sec->Name;
804  else
805    // Not null terminated, use all 8 bytes.
806    Name = StringRef(Sec->Name, 8);
807
808  // Check for string table entry. First byte is '/'.
809  if (Name[0] == '/') {
810    uint32_t Offset;
811    if (Name[1] == '/') {
812      if (decodeBase64StringEntry(Name.substr(2), Offset))
813        return object_error::parse_failed;
814    } else {
815      if (Name.substr(1).getAsInteger(10, Offset))
816        return object_error::parse_failed;
817    }
818    if (error_code EC = getString(Offset, Name))
819      return EC;
820  }
821
822  Res = Name;
823  return object_error::success;
824}
825
826error_code COFFObjectFile::getSectionContents(const coff_section *Sec,
827                                              ArrayRef<uint8_t> &Res) const {
828  // The only thing that we need to verify is that the contents is contained
829  // within the file bounds. We don't need to make sure it doesn't cover other
830  // data, as there's nothing that says that is not allowed.
831  uintptr_t ConStart = uintptr_t(base()) + Sec->PointerToRawData;
832  uintptr_t ConEnd = ConStart + Sec->SizeOfRawData;
833  if (ConEnd > uintptr_t(Data->getBufferEnd()))
834    return object_error::parse_failed;
835  Res = ArrayRef<uint8_t>(reinterpret_cast<const unsigned char*>(ConStart),
836                          Sec->SizeOfRawData);
837  return object_error::success;
838}
839
840const coff_relocation *COFFObjectFile::toRel(DataRefImpl Rel) const {
841  return reinterpret_cast<const coff_relocation*>(Rel.p);
842}
843
844void COFFObjectFile::moveRelocationNext(DataRefImpl &Rel) const {
845  Rel.p = reinterpret_cast<uintptr_t>(
846            reinterpret_cast<const coff_relocation*>(Rel.p) + 1);
847}
848
849error_code COFFObjectFile::getRelocationAddress(DataRefImpl Rel,
850                                                uint64_t &Res) const {
851  report_fatal_error("getRelocationAddress not implemented in COFFObjectFile");
852}
853
854error_code COFFObjectFile::getRelocationOffset(DataRefImpl Rel,
855                                               uint64_t &Res) const {
856  Res = toRel(Rel)->VirtualAddress;
857  return object_error::success;
858}
859
860symbol_iterator COFFObjectFile::getRelocationSymbol(DataRefImpl Rel) const {
861  const coff_relocation* R = toRel(Rel);
862  DataRefImpl Ref;
863  Ref.p = reinterpret_cast<uintptr_t>(SymbolTable + R->SymbolTableIndex);
864  return symbol_iterator(SymbolRef(Ref, this));
865}
866
867error_code COFFObjectFile::getRelocationType(DataRefImpl Rel,
868                                             uint64_t &Res) const {
869  const coff_relocation* R = toRel(Rel);
870  Res = R->Type;
871  return object_error::success;
872}
873
874const coff_section *
875COFFObjectFile::getCOFFSection(const SectionRef &Section) const {
876  return toSec(Section.getRawDataRefImpl());
877}
878
879const coff_symbol *
880COFFObjectFile::getCOFFSymbol(const SymbolRef &Symbol) const {
881  return toSymb(Symbol.getRawDataRefImpl());
882}
883
884const coff_relocation *
885COFFObjectFile::getCOFFRelocation(const RelocationRef &Reloc) const {
886  return toRel(Reloc.getRawDataRefImpl());
887}
888
889#define LLVM_COFF_SWITCH_RELOC_TYPE_NAME(reloc_type)                           \
890  case COFF::reloc_type:                                                       \
891    Res = #reloc_type;                                                         \
892    break;
893
894error_code COFFObjectFile::getRelocationTypeName(DataRefImpl Rel,
895                                          SmallVectorImpl<char> &Result) const {
896  const coff_relocation *Reloc = toRel(Rel);
897  StringRef Res;
898  switch (COFFHeader->Machine) {
899  case COFF::IMAGE_FILE_MACHINE_AMD64:
900    switch (Reloc->Type) {
901    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_ABSOLUTE);
902    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_ADDR64);
903    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_ADDR32);
904    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_ADDR32NB);
905    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32);
906    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32_1);
907    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32_2);
908    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32_3);
909    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32_4);
910    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_REL32_5);
911    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_SECTION);
912    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_SECREL);
913    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_SECREL7);
914    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_TOKEN);
915    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_SREL32);
916    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_PAIR);
917    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_AMD64_SSPAN32);
918    default:
919      Res = "Unknown";
920    }
921    break;
922  case COFF::IMAGE_FILE_MACHINE_ARMNT:
923    switch (Reloc->Type) {
924    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_ABSOLUTE);
925    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_ADDR32);
926    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_ADDR32NB);
927    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_BRANCH24);
928    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_BRANCH11);
929    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_TOKEN);
930    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_BLX24);
931    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_BLX11);
932    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_SECTION);
933    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_SECREL);
934    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_MOV32A);
935    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_MOV32T);
936    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_BRANCH20T);
937    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_BRANCH24T);
938    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_ARM_BLX23T);
939    default:
940      Res = "Unknown";
941    }
942    break;
943  case COFF::IMAGE_FILE_MACHINE_I386:
944    switch (Reloc->Type) {
945    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_ABSOLUTE);
946    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_DIR16);
947    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_REL16);
948    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_DIR32);
949    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_DIR32NB);
950    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_SEG12);
951    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_SECTION);
952    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_SECREL);
953    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_TOKEN);
954    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_SECREL7);
955    LLVM_COFF_SWITCH_RELOC_TYPE_NAME(IMAGE_REL_I386_REL32);
956    default:
957      Res = "Unknown";
958    }
959    break;
960  default:
961    Res = "Unknown";
962  }
963  Result.append(Res.begin(), Res.end());
964  return object_error::success;
965}
966
967#undef LLVM_COFF_SWITCH_RELOC_TYPE_NAME
968
969error_code COFFObjectFile::getRelocationValueString(DataRefImpl Rel,
970                                          SmallVectorImpl<char> &Result) const {
971  const coff_relocation *Reloc = toRel(Rel);
972  const coff_symbol *Symb = nullptr;
973  if (error_code EC = getSymbol(Reloc->SymbolTableIndex, Symb)) return EC;
974  DataRefImpl Sym;
975  Sym.p = reinterpret_cast<uintptr_t>(Symb);
976  StringRef SymName;
977  if (error_code EC = getSymbolName(Sym, SymName)) return EC;
978  Result.append(SymName.begin(), SymName.end());
979  return object_error::success;
980}
981
982error_code COFFObjectFile::getLibraryNext(DataRefImpl LibData,
983                                          LibraryRef &Result) const {
984  report_fatal_error("getLibraryNext not implemented in COFFObjectFile");
985}
986
987error_code COFFObjectFile::getLibraryPath(DataRefImpl LibData,
988                                          StringRef &Result) const {
989  report_fatal_error("getLibraryPath not implemented in COFFObjectFile");
990}
991
992bool ImportDirectoryEntryRef::
993operator==(const ImportDirectoryEntryRef &Other) const {
994  return ImportTable == Other.ImportTable && Index == Other.Index;
995}
996
997void ImportDirectoryEntryRef::moveNext() {
998  ++Index;
999}
1000
1001error_code ImportDirectoryEntryRef::
1002getImportTableEntry(const import_directory_table_entry *&Result) const {
1003  Result = ImportTable;
1004  return object_error::success;
1005}
1006
1007error_code ImportDirectoryEntryRef::getName(StringRef &Result) const {
1008  uintptr_t IntPtr = 0;
1009  if (error_code EC = OwningObject->getRvaPtr(ImportTable->NameRVA, IntPtr))
1010    return EC;
1011  Result = StringRef(reinterpret_cast<const char *>(IntPtr));
1012  return object_error::success;
1013}
1014
1015error_code ImportDirectoryEntryRef::getImportLookupEntry(
1016    const import_lookup_table_entry32 *&Result) const {
1017  uintptr_t IntPtr = 0;
1018  if (error_code EC =
1019          OwningObject->getRvaPtr(ImportTable->ImportLookupTableRVA, IntPtr))
1020    return EC;
1021  Result = reinterpret_cast<const import_lookup_table_entry32 *>(IntPtr);
1022  return object_error::success;
1023}
1024
1025bool ExportDirectoryEntryRef::
1026operator==(const ExportDirectoryEntryRef &Other) const {
1027  return ExportTable == Other.ExportTable && Index == Other.Index;
1028}
1029
1030void ExportDirectoryEntryRef::moveNext() {
1031  ++Index;
1032}
1033
1034// Returns the name of the current export symbol. If the symbol is exported only
1035// by ordinal, the empty string is set as a result.
1036error_code ExportDirectoryEntryRef::getDllName(StringRef &Result) const {
1037  uintptr_t IntPtr = 0;
1038  if (error_code EC = OwningObject->getRvaPtr(ExportTable->NameRVA, IntPtr))
1039    return EC;
1040  Result = StringRef(reinterpret_cast<const char *>(IntPtr));
1041  return object_error::success;
1042}
1043
1044// Returns the starting ordinal number.
1045error_code ExportDirectoryEntryRef::getOrdinalBase(uint32_t &Result) const {
1046  Result = ExportTable->OrdinalBase;
1047  return object_error::success;
1048}
1049
1050// Returns the export ordinal of the current export symbol.
1051error_code ExportDirectoryEntryRef::getOrdinal(uint32_t &Result) const {
1052  Result = ExportTable->OrdinalBase + Index;
1053  return object_error::success;
1054}
1055
1056// Returns the address of the current export symbol.
1057error_code ExportDirectoryEntryRef::getExportRVA(uint32_t &Result) const {
1058  uintptr_t IntPtr = 0;
1059  if (error_code EC = OwningObject->getRvaPtr(
1060          ExportTable->ExportAddressTableRVA, IntPtr))
1061    return EC;
1062  const export_address_table_entry *entry =
1063      reinterpret_cast<const export_address_table_entry *>(IntPtr);
1064  Result = entry[Index].ExportRVA;
1065  return object_error::success;
1066}
1067
1068// Returns the name of the current export symbol. If the symbol is exported only
1069// by ordinal, the empty string is set as a result.
1070error_code ExportDirectoryEntryRef::getSymbolName(StringRef &Result) const {
1071  uintptr_t IntPtr = 0;
1072  if (error_code EC = OwningObject->getRvaPtr(
1073          ExportTable->OrdinalTableRVA, IntPtr))
1074    return EC;
1075  const ulittle16_t *Start = reinterpret_cast<const ulittle16_t *>(IntPtr);
1076
1077  uint32_t NumEntries = ExportTable->NumberOfNamePointers;
1078  int Offset = 0;
1079  for (const ulittle16_t *I = Start, *E = Start + NumEntries;
1080       I < E; ++I, ++Offset) {
1081    if (*I != Index)
1082      continue;
1083    if (error_code EC = OwningObject->getRvaPtr(
1084            ExportTable->NamePointerRVA, IntPtr))
1085      return EC;
1086    const ulittle32_t *NamePtr = reinterpret_cast<const ulittle32_t *>(IntPtr);
1087    if (error_code EC = OwningObject->getRvaPtr(NamePtr[Offset], IntPtr))
1088      return EC;
1089    Result = StringRef(reinterpret_cast<const char *>(IntPtr));
1090    return object_error::success;
1091  }
1092  Result = "";
1093  return object_error::success;
1094}
1095
1096ErrorOr<ObjectFile *> ObjectFile::createCOFFObjectFile(MemoryBuffer *Object,
1097                                                       bool BufferOwned) {
1098  error_code EC;
1099  std::unique_ptr<COFFObjectFile> Ret(
1100      new COFFObjectFile(Object, EC, BufferOwned));
1101  if (EC)
1102    return EC;
1103  return Ret.release();
1104}
1105