1 //===- ELFObjectFile.cpp - 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 defines the ELFObjectFile class. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "llvm/ADT/SmallVector.h" 15 #include "llvm/ADT/StringSwitch.h" 16 #include "llvm/ADT/Triple.h" 17 #include "llvm/ADT/DenseMap.h" 18 #include "llvm/Object/ObjectFile.h" 19 #include "llvm/Support/ELF.h" 20 #include "llvm/Support/Endian.h" 21 #include "llvm/Support/ErrorHandling.h" 22 #include "llvm/Support/MemoryBuffer.h" 23 #include "llvm/Support/raw_ostream.h" 24 #include <algorithm> 25 #include <limits> 26 #include <utility> 27 28 using namespace llvm; 29 using namespace object; 30 31 // Templates to choose Elf_Addr and Elf_Off depending on is64Bits. 32 namespace { 33 template<support::endianness target_endianness> 34 struct ELFDataTypeTypedefHelperCommon { 35 typedef support::detail::packed_endian_specific_integral 36 <uint16_t, target_endianness, support::aligned> Elf_Half; 37 typedef support::detail::packed_endian_specific_integral 38 <uint32_t, target_endianness, support::aligned> Elf_Word; 39 typedef support::detail::packed_endian_specific_integral 40 <int32_t, target_endianness, support::aligned> Elf_Sword; 41 typedef support::detail::packed_endian_specific_integral 42 <uint64_t, target_endianness, support::aligned> Elf_Xword; 43 typedef support::detail::packed_endian_specific_integral 44 <int64_t, target_endianness, support::aligned> Elf_Sxword; 45 }; 46 } 47 48 namespace { 49 template<support::endianness target_endianness, bool is64Bits> 50 struct ELFDataTypeTypedefHelper; 51 52 /// ELF 32bit types. 53 template<support::endianness target_endianness> 54 struct ELFDataTypeTypedefHelper<target_endianness, false> 55 : ELFDataTypeTypedefHelperCommon<target_endianness> { 56 typedef support::detail::packed_endian_specific_integral 57 <uint32_t, target_endianness, support::aligned> Elf_Addr; 58 typedef support::detail::packed_endian_specific_integral 59 <uint32_t, target_endianness, support::aligned> Elf_Off; 60 }; 61 62 /// ELF 64bit types. 63 template<support::endianness target_endianness> 64 struct ELFDataTypeTypedefHelper<target_endianness, true> 65 : ELFDataTypeTypedefHelperCommon<target_endianness>{ 66 typedef support::detail::packed_endian_specific_integral 67 <uint64_t, target_endianness, support::aligned> Elf_Addr; 68 typedef support::detail::packed_endian_specific_integral 69 <uint64_t, target_endianness, support::aligned> Elf_Off; 70 }; 71 } 72 73 // I really don't like doing this, but the alternative is copypasta. 74 #define LLVM_ELF_IMPORT_TYPES(target_endianness, is64Bits) \ 75 typedef typename \ 76 ELFDataTypeTypedefHelper<target_endianness, is64Bits>::Elf_Addr Elf_Addr; \ 77 typedef typename \ 78 ELFDataTypeTypedefHelper<target_endianness, is64Bits>::Elf_Off Elf_Off; \ 79 typedef typename \ 80 ELFDataTypeTypedefHelper<target_endianness, is64Bits>::Elf_Half Elf_Half; \ 81 typedef typename \ 82 ELFDataTypeTypedefHelper<target_endianness, is64Bits>::Elf_Word Elf_Word; \ 83 typedef typename \ 84 ELFDataTypeTypedefHelper<target_endianness, is64Bits>::Elf_Sword Elf_Sword; \ 85 typedef typename \ 86 ELFDataTypeTypedefHelper<target_endianness, is64Bits>::Elf_Xword Elf_Xword; \ 87 typedef typename \ 88 ELFDataTypeTypedefHelper<target_endianness, is64Bits>::Elf_Sxword Elf_Sxword; 89 90 // Section header. 91 namespace { 92 template<support::endianness target_endianness, bool is64Bits> 93 struct Elf_Shdr_Base; 94 95 template<support::endianness target_endianness> 96 struct Elf_Shdr_Base<target_endianness, false> { 97 LLVM_ELF_IMPORT_TYPES(target_endianness, false) 98 Elf_Word sh_name; // Section name (index into string table) 99 Elf_Word sh_type; // Section type (SHT_*) 100 Elf_Word sh_flags; // Section flags (SHF_*) 101 Elf_Addr sh_addr; // Address where section is to be loaded 102 Elf_Off sh_offset; // File offset of section data, in bytes 103 Elf_Word sh_size; // Size of section, in bytes 104 Elf_Word sh_link; // Section type-specific header table index link 105 Elf_Word sh_info; // Section type-specific extra information 106 Elf_Word sh_addralign;// Section address alignment 107 Elf_Word sh_entsize; // Size of records contained within the section 108 }; 109 110 template<support::endianness target_endianness> 111 struct Elf_Shdr_Base<target_endianness, true> { 112 LLVM_ELF_IMPORT_TYPES(target_endianness, true) 113 Elf_Word sh_name; // Section name (index into string table) 114 Elf_Word sh_type; // Section type (SHT_*) 115 Elf_Xword sh_flags; // Section flags (SHF_*) 116 Elf_Addr sh_addr; // Address where section is to be loaded 117 Elf_Off sh_offset; // File offset of section data, in bytes 118 Elf_Xword sh_size; // Size of section, in bytes 119 Elf_Word sh_link; // Section type-specific header table index link 120 Elf_Word sh_info; // Section type-specific extra information 121 Elf_Xword sh_addralign;// Section address alignment 122 Elf_Xword sh_entsize; // Size of records contained within the section 123 }; 124 125 template<support::endianness target_endianness, bool is64Bits> 126 struct Elf_Shdr_Impl : Elf_Shdr_Base<target_endianness, is64Bits> { 127 using Elf_Shdr_Base<target_endianness, is64Bits>::sh_entsize; 128 using Elf_Shdr_Base<target_endianness, is64Bits>::sh_size; 129 130 /// @brief Get the number of entities this section contains if it has any. 131 unsigned getEntityCount() const { 132 if (sh_entsize == 0) 133 return 0; 134 return sh_size / sh_entsize; 135 } 136 }; 137 } 138 139 namespace { 140 template<support::endianness target_endianness, bool is64Bits> 141 struct Elf_Sym_Base; 142 143 template<support::endianness target_endianness> 144 struct Elf_Sym_Base<target_endianness, false> { 145 LLVM_ELF_IMPORT_TYPES(target_endianness, false) 146 Elf_Word st_name; // Symbol name (index into string table) 147 Elf_Addr st_value; // Value or address associated with the symbol 148 Elf_Word st_size; // Size of the symbol 149 unsigned char st_info; // Symbol's type and binding attributes 150 unsigned char st_other; // Must be zero; reserved 151 Elf_Half st_shndx; // Which section (header table index) it's defined in 152 }; 153 154 template<support::endianness target_endianness> 155 struct Elf_Sym_Base<target_endianness, true> { 156 LLVM_ELF_IMPORT_TYPES(target_endianness, true) 157 Elf_Word st_name; // Symbol name (index into string table) 158 unsigned char st_info; // Symbol's type and binding attributes 159 unsigned char st_other; // Must be zero; reserved 160 Elf_Half st_shndx; // Which section (header table index) it's defined in 161 Elf_Addr st_value; // Value or address associated with the symbol 162 Elf_Xword st_size; // Size of the symbol 163 }; 164 165 template<support::endianness target_endianness, bool is64Bits> 166 struct Elf_Sym_Impl : Elf_Sym_Base<target_endianness, is64Bits> { 167 using Elf_Sym_Base<target_endianness, is64Bits>::st_info; 168 169 // These accessors and mutators correspond to the ELF32_ST_BIND, 170 // ELF32_ST_TYPE, and ELF32_ST_INFO macros defined in the ELF specification: 171 unsigned char getBinding() const { return st_info >> 4; } 172 unsigned char getType() const { return st_info & 0x0f; } 173 void setBinding(unsigned char b) { setBindingAndType(b, getType()); } 174 void setType(unsigned char t) { setBindingAndType(getBinding(), t); } 175 void setBindingAndType(unsigned char b, unsigned char t) { 176 st_info = (b << 4) + (t & 0x0f); 177 } 178 }; 179 } 180 181 namespace { 182 template<support::endianness target_endianness, bool is64Bits, bool isRela> 183 struct Elf_Rel_Base; 184 185 template<support::endianness target_endianness> 186 struct Elf_Rel_Base<target_endianness, false, false> { 187 LLVM_ELF_IMPORT_TYPES(target_endianness, false) 188 Elf_Addr r_offset; // Location (file byte offset, or program virtual addr) 189 Elf_Word r_info; // Symbol table index and type of relocation to apply 190 }; 191 192 template<support::endianness target_endianness> 193 struct Elf_Rel_Base<target_endianness, true, false> { 194 LLVM_ELF_IMPORT_TYPES(target_endianness, true) 195 Elf_Addr r_offset; // Location (file byte offset, or program virtual addr) 196 Elf_Xword r_info; // Symbol table index and type of relocation to apply 197 }; 198 199 template<support::endianness target_endianness> 200 struct Elf_Rel_Base<target_endianness, false, true> { 201 LLVM_ELF_IMPORT_TYPES(target_endianness, false) 202 Elf_Addr r_offset; // Location (file byte offset, or program virtual addr) 203 Elf_Word r_info; // Symbol table index and type of relocation to apply 204 Elf_Sword r_addend; // Compute value for relocatable field by adding this 205 }; 206 207 template<support::endianness target_endianness> 208 struct Elf_Rel_Base<target_endianness, true, true> { 209 LLVM_ELF_IMPORT_TYPES(target_endianness, true) 210 Elf_Addr r_offset; // Location (file byte offset, or program virtual addr) 211 Elf_Xword r_info; // Symbol table index and type of relocation to apply 212 Elf_Sxword r_addend; // Compute value for relocatable field by adding this. 213 }; 214 215 template<support::endianness target_endianness, bool is64Bits, bool isRela> 216 struct Elf_Rel_Impl; 217 218 template<support::endianness target_endianness, bool isRela> 219 struct Elf_Rel_Impl<target_endianness, true, isRela> 220 : Elf_Rel_Base<target_endianness, true, isRela> { 221 using Elf_Rel_Base<target_endianness, true, isRela>::r_info; 222 LLVM_ELF_IMPORT_TYPES(target_endianness, true) 223 224 // These accessors and mutators correspond to the ELF64_R_SYM, ELF64_R_TYPE, 225 // and ELF64_R_INFO macros defined in the ELF specification: 226 uint64_t getSymbol() const { return (r_info >> 32); } 227 unsigned char getType() const { 228 return (unsigned char) (r_info & 0xffffffffL); 229 } 230 void setSymbol(uint64_t s) { setSymbolAndType(s, getType()); } 231 void setType(unsigned char t) { setSymbolAndType(getSymbol(), t); } 232 void setSymbolAndType(uint64_t s, unsigned char t) { 233 r_info = (s << 32) + (t&0xffffffffL); 234 } 235 }; 236 237 template<support::endianness target_endianness, bool isRela> 238 struct Elf_Rel_Impl<target_endianness, false, isRela> 239 : Elf_Rel_Base<target_endianness, false, isRela> { 240 using Elf_Rel_Base<target_endianness, false, isRela>::r_info; 241 LLVM_ELF_IMPORT_TYPES(target_endianness, false) 242 243 // These accessors and mutators correspond to the ELF32_R_SYM, ELF32_R_TYPE, 244 // and ELF32_R_INFO macros defined in the ELF specification: 245 uint32_t getSymbol() const { return (r_info >> 8); } 246 unsigned char getType() const { return (unsigned char) (r_info & 0x0ff); } 247 void setSymbol(uint32_t s) { setSymbolAndType(s, getType()); } 248 void setType(unsigned char t) { setSymbolAndType(getSymbol(), t); } 249 void setSymbolAndType(uint32_t s, unsigned char t) { 250 r_info = (s << 8) + t; 251 } 252 }; 253 254 } 255 256 namespace { 257 template<support::endianness target_endianness, bool is64Bits> 258 class ELFObjectFile : public ObjectFile { 259 LLVM_ELF_IMPORT_TYPES(target_endianness, is64Bits) 260 261 typedef Elf_Shdr_Impl<target_endianness, is64Bits> Elf_Shdr; 262 typedef Elf_Sym_Impl<target_endianness, is64Bits> Elf_Sym; 263 typedef Elf_Rel_Impl<target_endianness, is64Bits, false> Elf_Rel; 264 typedef Elf_Rel_Impl<target_endianness, is64Bits, true> Elf_Rela; 265 266 struct Elf_Ehdr { 267 unsigned char e_ident[ELF::EI_NIDENT]; // ELF Identification bytes 268 Elf_Half e_type; // Type of file (see ET_*) 269 Elf_Half e_machine; // Required architecture for this file (see EM_*) 270 Elf_Word e_version; // Must be equal to 1 271 Elf_Addr e_entry; // Address to jump to in order to start program 272 Elf_Off e_phoff; // Program header table's file offset, in bytes 273 Elf_Off e_shoff; // Section header table's file offset, in bytes 274 Elf_Word e_flags; // Processor-specific flags 275 Elf_Half e_ehsize; // Size of ELF header, in bytes 276 Elf_Half e_phentsize;// Size of an entry in the program header table 277 Elf_Half e_phnum; // Number of entries in the program header table 278 Elf_Half e_shentsize;// Size of an entry in the section header table 279 Elf_Half e_shnum; // Number of entries in the section header table 280 Elf_Half e_shstrndx; // Section header table index of section name 281 // string table 282 bool checkMagic() const { 283 return (memcmp(e_ident, ELF::ElfMagic, strlen(ELF::ElfMagic))) == 0; 284 } 285 unsigned char getFileClass() const { return e_ident[ELF::EI_CLASS]; } 286 unsigned char getDataEncoding() const { return e_ident[ELF::EI_DATA]; } 287 }; 288 289 typedef SmallVector<const Elf_Shdr*, 1> Sections_t; 290 typedef DenseMap<unsigned, unsigned> IndexMap_t; 291 typedef DenseMap<const Elf_Shdr*, SmallVector<uint32_t, 1> > RelocMap_t; 292 293 const Elf_Ehdr *Header; 294 const Elf_Shdr *SectionHeaderTable; 295 const Elf_Shdr *dot_shstrtab_sec; // Section header string table. 296 const Elf_Shdr *dot_strtab_sec; // Symbol header string table. 297 Sections_t SymbolTableSections; 298 IndexMap_t SymbolTableSectionsIndexMap; 299 DenseMap<const Elf_Sym*, Elf_Word> ExtendedSymbolTable; 300 301 /// @brief Map sections to an array of relocation sections that reference 302 /// them sorted by section index. 303 RelocMap_t SectionRelocMap; 304 305 /// @brief Get the relocation section that contains \a Rel. 306 const Elf_Shdr *getRelSection(DataRefImpl Rel) const { 307 return getSection(Rel.w.b); 308 } 309 310 void validateSymbol(DataRefImpl Symb) const; 311 bool isRelocationHasAddend(DataRefImpl Rel) const; 312 template<typename T> 313 const T *getEntry(uint16_t Section, uint32_t Entry) const; 314 template<typename T> 315 const T *getEntry(const Elf_Shdr *Section, uint32_t Entry) const; 316 const Elf_Sym *getSymbol(DataRefImpl Symb) const; 317 const Elf_Shdr *getSection(DataRefImpl index) const; 318 const Elf_Shdr *getSection(uint16_t index) const; 319 const Elf_Rel *getRel(DataRefImpl Rel) const; 320 const Elf_Rela *getRela(DataRefImpl Rela) const; 321 const char *getString(uint16_t section, uint32_t offset) const; 322 const char *getString(const Elf_Shdr *section, uint32_t offset) const; 323 error_code getSymbolName(const Elf_Sym *Symb, StringRef &Res) const; 324 325 protected: 326 virtual error_code getSymbolNext(DataRefImpl Symb, SymbolRef &Res) const; 327 virtual error_code getSymbolName(DataRefImpl Symb, StringRef &Res) const; 328 virtual error_code getSymbolOffset(DataRefImpl Symb, uint64_t &Res) const; 329 virtual error_code getSymbolAddress(DataRefImpl Symb, uint64_t &Res) const; 330 virtual error_code getSymbolSize(DataRefImpl Symb, uint64_t &Res) const; 331 virtual error_code getSymbolNMTypeChar(DataRefImpl Symb, char &Res) const; 332 virtual error_code isSymbolInternal(DataRefImpl Symb, bool &Res) const; 333 virtual error_code isSymbolGlobal(DataRefImpl Symb, bool &Res) const; 334 virtual error_code getSymbolType(DataRefImpl Symb, SymbolRef::SymbolType &Res) const; 335 336 virtual error_code getSectionNext(DataRefImpl Sec, SectionRef &Res) const; 337 virtual error_code getSectionName(DataRefImpl Sec, StringRef &Res) const; 338 virtual error_code getSectionAddress(DataRefImpl Sec, uint64_t &Res) const; 339 virtual error_code getSectionSize(DataRefImpl Sec, uint64_t &Res) const; 340 virtual error_code getSectionContents(DataRefImpl Sec, StringRef &Res) const; 341 virtual error_code getSectionAlignment(DataRefImpl Sec, uint64_t &Res) const; 342 virtual error_code isSectionText(DataRefImpl Sec, bool &Res) const; 343 virtual error_code isSectionData(DataRefImpl Sec, bool &Res) const; 344 virtual error_code isSectionBSS(DataRefImpl Sec, bool &Res) const; 345 virtual error_code sectionContainsSymbol(DataRefImpl Sec, DataRefImpl Symb, 346 bool &Result) const; 347 virtual relocation_iterator getSectionRelBegin(DataRefImpl Sec) const; 348 virtual relocation_iterator getSectionRelEnd(DataRefImpl Sec) const; 349 350 virtual error_code getRelocationNext(DataRefImpl Rel, 351 RelocationRef &Res) const; 352 virtual error_code getRelocationAddress(DataRefImpl Rel, 353 uint64_t &Res) const; 354 virtual error_code getRelocationSymbol(DataRefImpl Rel, 355 SymbolRef &Res) const; 356 virtual error_code getRelocationType(DataRefImpl Rel, 357 uint32_t &Res) const; 358 virtual error_code getRelocationTypeName(DataRefImpl Rel, 359 SmallVectorImpl<char> &Result) const; 360 virtual error_code getRelocationAdditionalInfo(DataRefImpl Rel, 361 int64_t &Res) const; 362 virtual error_code getRelocationValueString(DataRefImpl Rel, 363 SmallVectorImpl<char> &Result) const; 364 365 public: 366 ELFObjectFile(MemoryBuffer *Object, error_code &ec); 367 virtual symbol_iterator begin_symbols() const; 368 virtual symbol_iterator end_symbols() const; 369 virtual section_iterator begin_sections() const; 370 virtual section_iterator end_sections() const; 371 372 virtual uint8_t getBytesInAddress() const; 373 virtual StringRef getFileFormatName() const; 374 virtual unsigned getArch() const; 375 376 uint64_t getSymbolTableIndex(const Elf_Sym *symb) const; 377 }; 378 } // end namespace 379 380 template<support::endianness target_endianness, bool is64Bits> 381 void ELFObjectFile<target_endianness, is64Bits> 382 ::validateSymbol(DataRefImpl Symb) const { 383 const Elf_Sym *symb = getSymbol(Symb); 384 const Elf_Shdr *SymbolTableSection = SymbolTableSections[Symb.d.b]; 385 // FIXME: We really need to do proper error handling in the case of an invalid 386 // input file. Because we don't use exceptions, I think we'll just pass 387 // an error object around. 388 if (!( symb 389 && SymbolTableSection 390 && symb >= (const Elf_Sym*)(base() 391 + SymbolTableSection->sh_offset) 392 && symb < (const Elf_Sym*)(base() 393 + SymbolTableSection->sh_offset 394 + SymbolTableSection->sh_size))) 395 // FIXME: Proper error handling. 396 report_fatal_error("Symb must point to a valid symbol!"); 397 } 398 399 template<support::endianness target_endianness, bool is64Bits> 400 error_code ELFObjectFile<target_endianness, is64Bits> 401 ::getSymbolNext(DataRefImpl Symb, 402 SymbolRef &Result) const { 403 validateSymbol(Symb); 404 const Elf_Shdr *SymbolTableSection = SymbolTableSections[Symb.d.b]; 405 406 ++Symb.d.a; 407 // Check to see if we are at the end of this symbol table. 408 if (Symb.d.a >= SymbolTableSection->getEntityCount()) { 409 // We are at the end. If there are other symbol tables, jump to them. 410 ++Symb.d.b; 411 Symb.d.a = 1; // The 0th symbol in ELF is fake. 412 // Otherwise return the terminator. 413 if (Symb.d.b >= SymbolTableSections.size()) { 414 Symb.d.a = std::numeric_limits<uint32_t>::max(); 415 Symb.d.b = std::numeric_limits<uint32_t>::max(); 416 } 417 } 418 419 Result = SymbolRef(Symb, this); 420 return object_error::success; 421 } 422 423 template<support::endianness target_endianness, bool is64Bits> 424 error_code ELFObjectFile<target_endianness, is64Bits> 425 ::getSymbolName(DataRefImpl Symb, 426 StringRef &Result) const { 427 validateSymbol(Symb); 428 const Elf_Sym *symb = getSymbol(Symb); 429 return getSymbolName(symb, Result); 430 } 431 432 template<support::endianness target_endianness, bool is64Bits> 433 uint64_t ELFObjectFile<target_endianness, is64Bits> 434 ::getSymbolTableIndex(const Elf_Sym *symb) const { 435 if (symb->st_shndx == ELF::SHN_XINDEX) 436 return ExtendedSymbolTable.lookup(symb); 437 return symb->st_shndx; 438 } 439 440 template<support::endianness target_endianness, bool is64Bits> 441 error_code ELFObjectFile<target_endianness, is64Bits> 442 ::getSymbolOffset(DataRefImpl Symb, 443 uint64_t &Result) const { 444 validateSymbol(Symb); 445 const Elf_Sym *symb = getSymbol(Symb); 446 const Elf_Shdr *Section; 447 switch (getSymbolTableIndex(symb)) { 448 case ELF::SHN_COMMON: 449 // Undefined symbols have no address yet. 450 case ELF::SHN_UNDEF: 451 Result = UnknownAddressOrSize; 452 return object_error::success; 453 case ELF::SHN_ABS: 454 Result = symb->st_value; 455 return object_error::success; 456 default: Section = getSection(symb->st_shndx); 457 } 458 459 switch (symb->getType()) { 460 case ELF::STT_SECTION: 461 Result = Section ? Section->sh_addr : UnknownAddressOrSize; 462 return object_error::success; 463 case ELF::STT_FUNC: 464 case ELF::STT_OBJECT: 465 case ELF::STT_NOTYPE: 466 Result = symb->st_value; 467 return object_error::success; 468 default: 469 Result = UnknownAddressOrSize; 470 return object_error::success; 471 } 472 } 473 474 template<support::endianness target_endianness, bool is64Bits> 475 error_code ELFObjectFile<target_endianness, is64Bits> 476 ::getSymbolAddress(DataRefImpl Symb, 477 uint64_t &Result) const { 478 validateSymbol(Symb); 479 const Elf_Sym *symb = getSymbol(Symb); 480 const Elf_Shdr *Section; 481 switch (getSymbolTableIndex(symb)) { 482 case ELF::SHN_COMMON: // Fall through. 483 // Undefined symbols have no address yet. 484 case ELF::SHN_UNDEF: 485 Result = UnknownAddressOrSize; 486 return object_error::success; 487 case ELF::SHN_ABS: 488 Result = reinterpret_cast<uintptr_t>(base()+symb->st_value); 489 return object_error::success; 490 default: Section = getSection(getSymbolTableIndex(symb)); 491 } 492 const uint8_t* addr = base(); 493 if (Section) 494 addr += Section->sh_offset; 495 switch (symb->getType()) { 496 case ELF::STT_SECTION: 497 Result = reinterpret_cast<uintptr_t>(addr); 498 return object_error::success; 499 case ELF::STT_FUNC: // Fall through. 500 case ELF::STT_OBJECT: // Fall through. 501 case ELF::STT_NOTYPE: 502 addr += symb->st_value; 503 Result = reinterpret_cast<uintptr_t>(addr); 504 return object_error::success; 505 default: 506 Result = UnknownAddressOrSize; 507 return object_error::success; 508 } 509 } 510 511 template<support::endianness target_endianness, bool is64Bits> 512 error_code ELFObjectFile<target_endianness, is64Bits> 513 ::getSymbolSize(DataRefImpl Symb, 514 uint64_t &Result) const { 515 validateSymbol(Symb); 516 const Elf_Sym *symb = getSymbol(Symb); 517 if (symb->st_size == 0) 518 Result = UnknownAddressOrSize; 519 Result = symb->st_size; 520 return object_error::success; 521 } 522 523 template<support::endianness target_endianness, bool is64Bits> 524 error_code ELFObjectFile<target_endianness, is64Bits> 525 ::getSymbolNMTypeChar(DataRefImpl Symb, 526 char &Result) const { 527 validateSymbol(Symb); 528 const Elf_Sym *symb = getSymbol(Symb); 529 const Elf_Shdr *Section = getSection(getSymbolTableIndex(symb)); 530 531 char ret = '?'; 532 533 if (Section) { 534 switch (Section->sh_type) { 535 case ELF::SHT_PROGBITS: 536 case ELF::SHT_DYNAMIC: 537 switch (Section->sh_flags) { 538 case (ELF::SHF_ALLOC | ELF::SHF_EXECINSTR): 539 ret = 't'; break; 540 case (ELF::SHF_ALLOC | ELF::SHF_WRITE): 541 ret = 'd'; break; 542 case ELF::SHF_ALLOC: 543 case (ELF::SHF_ALLOC | ELF::SHF_MERGE): 544 case (ELF::SHF_ALLOC | ELF::SHF_MERGE | ELF::SHF_STRINGS): 545 ret = 'r'; break; 546 } 547 break; 548 case ELF::SHT_NOBITS: ret = 'b'; 549 } 550 } 551 552 switch (symb->st_shndx) { 553 case ELF::SHN_UNDEF: 554 if (ret == '?') 555 ret = 'U'; 556 break; 557 case ELF::SHN_ABS: ret = 'a'; break; 558 case ELF::SHN_COMMON: ret = 'c'; break; 559 } 560 561 switch (symb->getBinding()) { 562 case ELF::STB_GLOBAL: ret = ::toupper(ret); break; 563 case ELF::STB_WEAK: 564 if (symb->st_shndx == ELF::SHN_UNDEF) 565 ret = 'w'; 566 else 567 if (symb->getType() == ELF::STT_OBJECT) 568 ret = 'V'; 569 else 570 ret = 'W'; 571 } 572 573 if (ret == '?' && symb->getType() == ELF::STT_SECTION) { 574 StringRef name; 575 if (error_code ec = getSymbolName(Symb, name)) 576 return ec; 577 Result = StringSwitch<char>(name) 578 .StartsWith(".debug", 'N') 579 .StartsWith(".note", 'n') 580 .Default('?'); 581 return object_error::success; 582 } 583 584 Result = ret; 585 return object_error::success; 586 } 587 588 template<support::endianness target_endianness, bool is64Bits> 589 error_code ELFObjectFile<target_endianness, is64Bits> 590 ::getSymbolType(DataRefImpl Symb, 591 SymbolRef::SymbolType &Result) const { 592 validateSymbol(Symb); 593 const Elf_Sym *symb = getSymbol(Symb); 594 595 if (getSymbolTableIndex(symb) == ELF::SHN_UNDEF) { 596 Result = SymbolRef::ST_External; 597 return object_error::success; 598 } 599 600 switch (symb->getType()) { 601 case ELF::STT_FUNC: 602 Result = SymbolRef::ST_Function; 603 break; 604 case ELF::STT_OBJECT: 605 Result = SymbolRef::ST_Data; 606 break; 607 default: 608 Result = SymbolRef::ST_Other; 609 break; 610 } 611 return object_error::success; 612 } 613 614 template<support::endianness target_endianness, bool is64Bits> 615 error_code ELFObjectFile<target_endianness, is64Bits> 616 ::isSymbolGlobal(DataRefImpl Symb, 617 bool &Result) const { 618 validateSymbol(Symb); 619 const Elf_Sym *symb = getSymbol(Symb); 620 621 Result = symb->getBinding() == ELF::STB_GLOBAL; 622 return object_error::success; 623 } 624 625 template<support::endianness target_endianness, bool is64Bits> 626 error_code ELFObjectFile<target_endianness, is64Bits> 627 ::isSymbolInternal(DataRefImpl Symb, 628 bool &Result) const { 629 validateSymbol(Symb); 630 const Elf_Sym *symb = getSymbol(Symb); 631 632 if ( symb->getType() == ELF::STT_FILE 633 || symb->getType() == ELF::STT_SECTION) 634 Result = true; 635 Result = false; 636 return object_error::success; 637 } 638 639 template<support::endianness target_endianness, bool is64Bits> 640 error_code ELFObjectFile<target_endianness, is64Bits> 641 ::getSectionNext(DataRefImpl Sec, SectionRef &Result) const { 642 const uint8_t *sec = reinterpret_cast<const uint8_t *>(Sec.p); 643 sec += Header->e_shentsize; 644 Sec.p = reinterpret_cast<intptr_t>(sec); 645 Result = SectionRef(Sec, this); 646 return object_error::success; 647 } 648 649 template<support::endianness target_endianness, bool is64Bits> 650 error_code ELFObjectFile<target_endianness, is64Bits> 651 ::getSectionName(DataRefImpl Sec, 652 StringRef &Result) const { 653 const Elf_Shdr *sec = reinterpret_cast<const Elf_Shdr *>(Sec.p); 654 Result = StringRef(getString(dot_shstrtab_sec, sec->sh_name)); 655 return object_error::success; 656 } 657 658 template<support::endianness target_endianness, bool is64Bits> 659 error_code ELFObjectFile<target_endianness, is64Bits> 660 ::getSectionAddress(DataRefImpl Sec, 661 uint64_t &Result) const { 662 const Elf_Shdr *sec = reinterpret_cast<const Elf_Shdr *>(Sec.p); 663 Result = sec->sh_addr; 664 return object_error::success; 665 } 666 667 template<support::endianness target_endianness, bool is64Bits> 668 error_code ELFObjectFile<target_endianness, is64Bits> 669 ::getSectionSize(DataRefImpl Sec, 670 uint64_t &Result) const { 671 const Elf_Shdr *sec = reinterpret_cast<const Elf_Shdr *>(Sec.p); 672 Result = sec->sh_size; 673 return object_error::success; 674 } 675 676 template<support::endianness target_endianness, bool is64Bits> 677 error_code ELFObjectFile<target_endianness, is64Bits> 678 ::getSectionContents(DataRefImpl Sec, 679 StringRef &Result) const { 680 const Elf_Shdr *sec = reinterpret_cast<const Elf_Shdr *>(Sec.p); 681 const char *start = (const char*)base() + sec->sh_offset; 682 Result = StringRef(start, sec->sh_size); 683 return object_error::success; 684 } 685 686 template<support::endianness target_endianness, bool is64Bits> 687 error_code ELFObjectFile<target_endianness, is64Bits> 688 ::getSectionAlignment(DataRefImpl Sec, 689 uint64_t &Result) const { 690 const Elf_Shdr *sec = reinterpret_cast<const Elf_Shdr *>(Sec.p); 691 Result = sec->sh_addralign; 692 return object_error::success; 693 } 694 695 template<support::endianness target_endianness, bool is64Bits> 696 error_code ELFObjectFile<target_endianness, is64Bits> 697 ::isSectionText(DataRefImpl Sec, 698 bool &Result) const { 699 const Elf_Shdr *sec = reinterpret_cast<const Elf_Shdr *>(Sec.p); 700 if (sec->sh_flags & ELF::SHF_EXECINSTR) 701 Result = true; 702 else 703 Result = false; 704 return object_error::success; 705 } 706 707 template<support::endianness target_endianness, bool is64Bits> 708 error_code ELFObjectFile<target_endianness, is64Bits> 709 ::isSectionData(DataRefImpl Sec, 710 bool &Result) const { 711 const Elf_Shdr *sec = reinterpret_cast<const Elf_Shdr *>(Sec.p); 712 if (sec->sh_flags & (ELF::SHF_ALLOC | ELF::SHF_WRITE) 713 && sec->sh_type == ELF::SHT_PROGBITS) 714 Result = true; 715 else 716 Result = false; 717 return object_error::success; 718 } 719 720 template<support::endianness target_endianness, bool is64Bits> 721 error_code ELFObjectFile<target_endianness, is64Bits> 722 ::isSectionBSS(DataRefImpl Sec, 723 bool &Result) const { 724 const Elf_Shdr *sec = reinterpret_cast<const Elf_Shdr *>(Sec.p); 725 if (sec->sh_flags & (ELF::SHF_ALLOC | ELF::SHF_WRITE) 726 && sec->sh_type == ELF::SHT_NOBITS) 727 Result = true; 728 else 729 Result = false; 730 return object_error::success; 731 } 732 733 template<support::endianness target_endianness, bool is64Bits> 734 error_code ELFObjectFile<target_endianness, is64Bits> 735 ::sectionContainsSymbol(DataRefImpl Sec, 736 DataRefImpl Symb, 737 bool &Result) const { 738 // FIXME: Unimplemented. 739 Result = false; 740 return object_error::success; 741 } 742 743 template<support::endianness target_endianness, bool is64Bits> 744 relocation_iterator ELFObjectFile<target_endianness, is64Bits> 745 ::getSectionRelBegin(DataRefImpl Sec) const { 746 DataRefImpl RelData; 747 memset(&RelData, 0, sizeof(RelData)); 748 const Elf_Shdr *sec = reinterpret_cast<const Elf_Shdr *>(Sec.p); 749 typename RelocMap_t::const_iterator ittr = SectionRelocMap.find(sec); 750 if (sec != 0 && ittr != SectionRelocMap.end()) { 751 RelData.w.a = getSection(ittr->second[0])->sh_link; 752 RelData.w.b = ittr->second[0]; 753 RelData.w.c = 0; 754 } 755 return relocation_iterator(RelocationRef(RelData, this)); 756 } 757 758 template<support::endianness target_endianness, bool is64Bits> 759 relocation_iterator ELFObjectFile<target_endianness, is64Bits> 760 ::getSectionRelEnd(DataRefImpl Sec) const { 761 DataRefImpl RelData; 762 memset(&RelData, 0, sizeof(RelData)); 763 const Elf_Shdr *sec = reinterpret_cast<const Elf_Shdr *>(Sec.p); 764 typename RelocMap_t::const_iterator ittr = SectionRelocMap.find(sec); 765 if (sec != 0 && ittr != SectionRelocMap.end()) { 766 // Get the index of the last relocation section for this section. 767 std::size_t relocsecindex = ittr->second[ittr->second.size() - 1]; 768 const Elf_Shdr *relocsec = getSection(relocsecindex); 769 RelData.w.a = relocsec->sh_link; 770 RelData.w.b = relocsecindex; 771 RelData.w.c = relocsec->sh_size / relocsec->sh_entsize; 772 } 773 return relocation_iterator(RelocationRef(RelData, this)); 774 } 775 776 // Relocations 777 template<support::endianness target_endianness, bool is64Bits> 778 error_code ELFObjectFile<target_endianness, is64Bits> 779 ::getRelocationNext(DataRefImpl Rel, 780 RelocationRef &Result) const { 781 ++Rel.w.c; 782 const Elf_Shdr *relocsec = getSection(Rel.w.b); 783 if (Rel.w.c >= (relocsec->sh_size / relocsec->sh_entsize)) { 784 // We have reached the end of the relocations for this section. See if there 785 // is another relocation section. 786 typename RelocMap_t::mapped_type relocseclist = 787 SectionRelocMap.lookup(getSection(Rel.w.a)); 788 789 // Do a binary search for the current reloc section index (which must be 790 // present). Then get the next one. 791 typename RelocMap_t::mapped_type::const_iterator loc = 792 std::lower_bound(relocseclist.begin(), relocseclist.end(), Rel.w.b); 793 ++loc; 794 795 // If there is no next one, don't do anything. The ++Rel.w.c above sets Rel 796 // to the end iterator. 797 if (loc != relocseclist.end()) { 798 Rel.w.b = *loc; 799 Rel.w.a = 0; 800 } 801 } 802 Result = RelocationRef(Rel, this); 803 return object_error::success; 804 } 805 806 template<support::endianness target_endianness, bool is64Bits> 807 error_code ELFObjectFile<target_endianness, is64Bits> 808 ::getRelocationSymbol(DataRefImpl Rel, 809 SymbolRef &Result) const { 810 uint32_t symbolIdx; 811 const Elf_Shdr *sec = getSection(Rel.w.b); 812 switch (sec->sh_type) { 813 default : 814 report_fatal_error("Invalid section type in Rel!"); 815 case ELF::SHT_REL : { 816 symbolIdx = getRel(Rel)->getSymbol(); 817 break; 818 } 819 case ELF::SHT_RELA : { 820 symbolIdx = getRela(Rel)->getSymbol(); 821 break; 822 } 823 } 824 DataRefImpl SymbolData; 825 IndexMap_t::const_iterator it = SymbolTableSectionsIndexMap.find(sec->sh_link); 826 if (it == SymbolTableSectionsIndexMap.end()) 827 report_fatal_error("Relocation symbol table not found!"); 828 SymbolData.d.a = symbolIdx; 829 SymbolData.d.b = it->second; 830 Result = SymbolRef(SymbolData, this); 831 return object_error::success; 832 } 833 834 template<support::endianness target_endianness, bool is64Bits> 835 error_code ELFObjectFile<target_endianness, is64Bits> 836 ::getRelocationAddress(DataRefImpl Rel, 837 uint64_t &Result) const { 838 uint64_t offset; 839 const Elf_Shdr *sec = getSection(Rel.w.b); 840 switch (sec->sh_type) { 841 default : 842 report_fatal_error("Invalid section type in Rel!"); 843 case ELF::SHT_REL : { 844 offset = getRel(Rel)->r_offset; 845 break; 846 } 847 case ELF::SHT_RELA : { 848 offset = getRela(Rel)->r_offset; 849 break; 850 } 851 } 852 853 Result = offset; 854 return object_error::success; 855 } 856 857 template<support::endianness target_endianness, bool is64Bits> 858 error_code ELFObjectFile<target_endianness, is64Bits> 859 ::getRelocationType(DataRefImpl Rel, 860 uint32_t &Result) const { 861 const Elf_Shdr *sec = getSection(Rel.w.b); 862 switch (sec->sh_type) { 863 default : 864 report_fatal_error("Invalid section type in Rel!"); 865 case ELF::SHT_REL : { 866 Result = getRel(Rel)->getType(); 867 break; 868 } 869 case ELF::SHT_RELA : { 870 Result = getRela(Rel)->getType(); 871 break; 872 } 873 } 874 return object_error::success; 875 } 876 877 #define LLVM_ELF_SWITCH_RELOC_TYPE_NAME(enum) \ 878 case ELF::enum: res = #enum; break; 879 880 template<support::endianness target_endianness, bool is64Bits> 881 error_code ELFObjectFile<target_endianness, is64Bits> 882 ::getRelocationTypeName(DataRefImpl Rel, 883 SmallVectorImpl<char> &Result) const { 884 const Elf_Shdr *sec = getSection(Rel.w.b); 885 uint8_t type; 886 StringRef res; 887 switch (sec->sh_type) { 888 default : 889 return object_error::parse_failed; 890 case ELF::SHT_REL : { 891 type = getRel(Rel)->getType(); 892 break; 893 } 894 case ELF::SHT_RELA : { 895 type = getRela(Rel)->getType(); 896 break; 897 } 898 } 899 switch (Header->e_machine) { 900 case ELF::EM_X86_64: 901 switch (type) { 902 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_NONE); 903 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_64); 904 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_PC32); 905 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_GOT32); 906 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_PLT32); 907 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_COPY); 908 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_GLOB_DAT); 909 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_JUMP_SLOT); 910 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_RELATIVE); 911 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_GOTPCREL); 912 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_32); 913 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_32S); 914 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_16); 915 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_PC16); 916 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_8); 917 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_PC8); 918 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_DTPMOD64); 919 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_DTPOFF64); 920 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_TPOFF64); 921 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_TLSGD); 922 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_TLSLD); 923 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_DTPOFF32); 924 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_GOTTPOFF); 925 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_TPOFF32); 926 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_PC64); 927 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_GOTOFF64); 928 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_GOTPC32); 929 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_SIZE32); 930 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_SIZE64); 931 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_GOTPC32_TLSDESC); 932 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_TLSDESC_CALL); 933 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_TLSDESC); 934 default: 935 res = "Unknown"; 936 } 937 break; 938 case ELF::EM_386: 939 switch (type) { 940 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_NONE); 941 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_32); 942 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_PC32); 943 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_GOT32); 944 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_PLT32); 945 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_COPY); 946 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_GLOB_DAT); 947 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_JUMP_SLOT); 948 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_RELATIVE); 949 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_GOTOFF); 950 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_GOTPC); 951 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_32PLT); 952 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_TPOFF); 953 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_IE); 954 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_GOTIE); 955 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_LE); 956 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_GD); 957 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_LDM); 958 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_16); 959 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_PC16); 960 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_8); 961 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_PC8); 962 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_GD_32); 963 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_GD_PUSH); 964 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_GD_CALL); 965 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_GD_POP); 966 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_LDM_32); 967 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_LDM_PUSH); 968 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_LDM_CALL); 969 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_LDM_POP); 970 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_LDO_32); 971 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_IE_32); 972 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_LE_32); 973 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_DTPMOD32); 974 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_DTPOFF32); 975 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_TPOFF32); 976 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_GOTDESC); 977 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_DESC_CALL); 978 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_DESC); 979 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_IRELATIVE); 980 default: 981 res = "Unknown"; 982 } 983 break; 984 default: 985 res = "Unknown"; 986 } 987 Result.append(res.begin(), res.end()); 988 return object_error::success; 989 } 990 991 #undef LLVM_ELF_SWITCH_RELOC_TYPE_NAME 992 993 template<support::endianness target_endianness, bool is64Bits> 994 error_code ELFObjectFile<target_endianness, is64Bits> 995 ::getRelocationAdditionalInfo(DataRefImpl Rel, 996 int64_t &Result) const { 997 const Elf_Shdr *sec = getSection(Rel.w.b); 998 switch (sec->sh_type) { 999 default : 1000 report_fatal_error("Invalid section type in Rel!"); 1001 case ELF::SHT_REL : { 1002 Result = 0; 1003 return object_error::success; 1004 } 1005 case ELF::SHT_RELA : { 1006 Result = getRela(Rel)->r_addend; 1007 return object_error::success; 1008 } 1009 } 1010 } 1011 1012 template<support::endianness target_endianness, bool is64Bits> 1013 error_code ELFObjectFile<target_endianness, is64Bits> 1014 ::getRelocationValueString(DataRefImpl Rel, 1015 SmallVectorImpl<char> &Result) const { 1016 const Elf_Shdr *sec = getSection(Rel.w.b); 1017 uint8_t type; 1018 StringRef res; 1019 int64_t addend = 0; 1020 uint16_t symbol_index = 0; 1021 switch (sec->sh_type) { 1022 default : 1023 return object_error::parse_failed; 1024 case ELF::SHT_REL : { 1025 type = getRel(Rel)->getType(); 1026 symbol_index = getRel(Rel)->getSymbol(); 1027 // TODO: Read implicit addend from section data. 1028 break; 1029 } 1030 case ELF::SHT_RELA : { 1031 type = getRela(Rel)->getType(); 1032 symbol_index = getRela(Rel)->getSymbol(); 1033 addend = getRela(Rel)->r_addend; 1034 break; 1035 } 1036 } 1037 const Elf_Sym *symb = getEntry<Elf_Sym>(sec->sh_link, symbol_index); 1038 StringRef symname; 1039 if (error_code ec = getSymbolName(symb, symname)) 1040 return ec; 1041 switch (Header->e_machine) { 1042 case ELF::EM_X86_64: 1043 switch (type) { 1044 case ELF::R_X86_64_32S: 1045 res = symname; 1046 break; 1047 case ELF::R_X86_64_PC32: { 1048 std::string fmtbuf; 1049 raw_string_ostream fmt(fmtbuf); 1050 fmt << symname << (addend < 0 ? "" : "+") << addend << "-P"; 1051 fmt.flush(); 1052 Result.append(fmtbuf.begin(), fmtbuf.end()); 1053 } 1054 break; 1055 default: 1056 res = "Unknown"; 1057 } 1058 break; 1059 default: 1060 res = "Unknown"; 1061 } 1062 if (Result.empty()) 1063 Result.append(res.begin(), res.end()); 1064 return object_error::success; 1065 } 1066 1067 template<support::endianness target_endianness, bool is64Bits> 1068 ELFObjectFile<target_endianness, is64Bits>::ELFObjectFile(MemoryBuffer *Object 1069 , error_code &ec) 1070 : ObjectFile(Binary::isELF, Object, ec) 1071 , SectionHeaderTable(0) 1072 , dot_shstrtab_sec(0) 1073 , dot_strtab_sec(0) { 1074 Header = reinterpret_cast<const Elf_Ehdr *>(base()); 1075 1076 if (Header->e_shoff == 0) 1077 return; 1078 1079 SectionHeaderTable = 1080 reinterpret_cast<const Elf_Shdr *>(base() + Header->e_shoff); 1081 uint32_t SectionTableSize = Header->e_shnum * Header->e_shentsize; 1082 if (!( (const uint8_t *)SectionHeaderTable + SectionTableSize 1083 <= base() + Data->getBufferSize())) 1084 // FIXME: Proper error handling. 1085 report_fatal_error("Section table goes past end of file!"); 1086 1087 1088 // To find the symbol tables we walk the section table to find SHT_SYMTAB. 1089 const Elf_Shdr* SymbolTableSectionHeaderIndex = 0; 1090 const Elf_Shdr* sh = reinterpret_cast<const Elf_Shdr*>(SectionHeaderTable); 1091 for (unsigned i = 0; i < Header->e_shnum; ++i) { 1092 if (sh->sh_type == ELF::SHT_SYMTAB_SHNDX) { 1093 if (SymbolTableSectionHeaderIndex) 1094 // FIXME: Proper error handling. 1095 report_fatal_error("More than one .symtab_shndx!"); 1096 SymbolTableSectionHeaderIndex = sh; 1097 } 1098 if (sh->sh_type == ELF::SHT_SYMTAB) { 1099 SymbolTableSectionsIndexMap[i] = SymbolTableSections.size(); 1100 SymbolTableSections.push_back(sh); 1101 } 1102 if (sh->sh_type == ELF::SHT_REL || sh->sh_type == ELF::SHT_RELA) { 1103 SectionRelocMap[getSection(sh->sh_link)].push_back(i); 1104 } 1105 ++sh; 1106 } 1107 1108 // Sort section relocation lists by index. 1109 for (typename RelocMap_t::iterator i = SectionRelocMap.begin(), 1110 e = SectionRelocMap.end(); i != e; ++i) { 1111 std::sort(i->second.begin(), i->second.end()); 1112 } 1113 1114 // Get string table sections. 1115 dot_shstrtab_sec = getSection(Header->e_shstrndx); 1116 if (dot_shstrtab_sec) { 1117 // Verify that the last byte in the string table in a null. 1118 if (((const char*)base() + dot_shstrtab_sec->sh_offset) 1119 [dot_shstrtab_sec->sh_size - 1] != 0) 1120 // FIXME: Proper error handling. 1121 report_fatal_error("String table must end with a null terminator!"); 1122 } 1123 1124 // Merge this into the above loop. 1125 for (const char *i = reinterpret_cast<const char *>(SectionHeaderTable), 1126 *e = i + Header->e_shnum * Header->e_shentsize; 1127 i != e; i += Header->e_shentsize) { 1128 const Elf_Shdr *sh = reinterpret_cast<const Elf_Shdr*>(i); 1129 if (sh->sh_type == ELF::SHT_STRTAB) { 1130 StringRef SectionName(getString(dot_shstrtab_sec, sh->sh_name)); 1131 if (SectionName == ".strtab") { 1132 if (dot_strtab_sec != 0) 1133 // FIXME: Proper error handling. 1134 report_fatal_error("Already found section named .strtab!"); 1135 dot_strtab_sec = sh; 1136 const char *dot_strtab = (const char*)base() + sh->sh_offset; 1137 if (dot_strtab[sh->sh_size - 1] != 0) 1138 // FIXME: Proper error handling. 1139 report_fatal_error("String table must end with a null terminator!"); 1140 } 1141 } 1142 } 1143 1144 // Build symbol name side-mapping if there is one. 1145 if (SymbolTableSectionHeaderIndex) { 1146 const Elf_Word *ShndxTable = reinterpret_cast<const Elf_Word*>(base() + 1147 SymbolTableSectionHeaderIndex->sh_offset); 1148 error_code ec; 1149 for (symbol_iterator si = begin_symbols(), 1150 se = end_symbols(); si != se; si.increment(ec)) { 1151 if (ec) 1152 report_fatal_error("Fewer extended symbol table entries than symbols!"); 1153 if (*ShndxTable != ELF::SHN_UNDEF) 1154 ExtendedSymbolTable[getSymbol(si->getRawDataRefImpl())] = *ShndxTable; 1155 ++ShndxTable; 1156 } 1157 } 1158 } 1159 1160 template<support::endianness target_endianness, bool is64Bits> 1161 symbol_iterator ELFObjectFile<target_endianness, is64Bits> 1162 ::begin_symbols() const { 1163 DataRefImpl SymbolData; 1164 memset(&SymbolData, 0, sizeof(SymbolData)); 1165 if (SymbolTableSections.size() == 0) { 1166 SymbolData.d.a = std::numeric_limits<uint32_t>::max(); 1167 SymbolData.d.b = std::numeric_limits<uint32_t>::max(); 1168 } else { 1169 SymbolData.d.a = 1; // The 0th symbol in ELF is fake. 1170 SymbolData.d.b = 0; 1171 } 1172 return symbol_iterator(SymbolRef(SymbolData, this)); 1173 } 1174 1175 template<support::endianness target_endianness, bool is64Bits> 1176 symbol_iterator ELFObjectFile<target_endianness, is64Bits> 1177 ::end_symbols() const { 1178 DataRefImpl SymbolData; 1179 memset(&SymbolData, 0, sizeof(SymbolData)); 1180 SymbolData.d.a = std::numeric_limits<uint32_t>::max(); 1181 SymbolData.d.b = std::numeric_limits<uint32_t>::max(); 1182 return symbol_iterator(SymbolRef(SymbolData, this)); 1183 } 1184 1185 template<support::endianness target_endianness, bool is64Bits> 1186 section_iterator ELFObjectFile<target_endianness, is64Bits> 1187 ::begin_sections() const { 1188 DataRefImpl ret; 1189 memset(&ret, 0, sizeof(DataRefImpl)); 1190 ret.p = reinterpret_cast<intptr_t>(base() + Header->e_shoff); 1191 return section_iterator(SectionRef(ret, this)); 1192 } 1193 1194 template<support::endianness target_endianness, bool is64Bits> 1195 section_iterator ELFObjectFile<target_endianness, is64Bits> 1196 ::end_sections() const { 1197 DataRefImpl ret; 1198 memset(&ret, 0, sizeof(DataRefImpl)); 1199 ret.p = reinterpret_cast<intptr_t>(base() 1200 + Header->e_shoff 1201 + (Header->e_shentsize * Header->e_shnum)); 1202 return section_iterator(SectionRef(ret, this)); 1203 } 1204 1205 template<support::endianness target_endianness, bool is64Bits> 1206 uint8_t ELFObjectFile<target_endianness, is64Bits>::getBytesInAddress() const { 1207 return is64Bits ? 8 : 4; 1208 } 1209 1210 template<support::endianness target_endianness, bool is64Bits> 1211 StringRef ELFObjectFile<target_endianness, is64Bits> 1212 ::getFileFormatName() const { 1213 switch(Header->e_ident[ELF::EI_CLASS]) { 1214 case ELF::ELFCLASS32: 1215 switch(Header->e_machine) { 1216 case ELF::EM_386: 1217 return "ELF32-i386"; 1218 case ELF::EM_X86_64: 1219 return "ELF32-x86-64"; 1220 case ELF::EM_ARM: 1221 return "ELF32-arm"; 1222 default: 1223 return "ELF32-unknown"; 1224 } 1225 case ELF::ELFCLASS64: 1226 switch(Header->e_machine) { 1227 case ELF::EM_386: 1228 return "ELF64-i386"; 1229 case ELF::EM_X86_64: 1230 return "ELF64-x86-64"; 1231 default: 1232 return "ELF64-unknown"; 1233 } 1234 default: 1235 // FIXME: Proper error handling. 1236 report_fatal_error("Invalid ELFCLASS!"); 1237 } 1238 } 1239 1240 template<support::endianness target_endianness, bool is64Bits> 1241 unsigned ELFObjectFile<target_endianness, is64Bits>::getArch() const { 1242 switch(Header->e_machine) { 1243 case ELF::EM_386: 1244 return Triple::x86; 1245 case ELF::EM_X86_64: 1246 return Triple::x86_64; 1247 case ELF::EM_ARM: 1248 return Triple::arm; 1249 default: 1250 return Triple::UnknownArch; 1251 } 1252 } 1253 1254 1255 template<support::endianness target_endianness, bool is64Bits> 1256 template<typename T> 1257 inline const T * 1258 ELFObjectFile<target_endianness, is64Bits>::getEntry(uint16_t Section, 1259 uint32_t Entry) const { 1260 return getEntry<T>(getSection(Section), Entry); 1261 } 1262 1263 template<support::endianness target_endianness, bool is64Bits> 1264 template<typename T> 1265 inline const T * 1266 ELFObjectFile<target_endianness, is64Bits>::getEntry(const Elf_Shdr * Section, 1267 uint32_t Entry) const { 1268 return reinterpret_cast<const T *>( 1269 base() 1270 + Section->sh_offset 1271 + (Entry * Section->sh_entsize)); 1272 } 1273 1274 template<support::endianness target_endianness, bool is64Bits> 1275 const typename ELFObjectFile<target_endianness, is64Bits>::Elf_Sym * 1276 ELFObjectFile<target_endianness, is64Bits>::getSymbol(DataRefImpl Symb) const { 1277 return getEntry<Elf_Sym>(SymbolTableSections[Symb.d.b], Symb.d.a); 1278 } 1279 1280 template<support::endianness target_endianness, bool is64Bits> 1281 const typename ELFObjectFile<target_endianness, is64Bits>::Elf_Rel * 1282 ELFObjectFile<target_endianness, is64Bits>::getRel(DataRefImpl Rel) const { 1283 return getEntry<Elf_Rel>(Rel.w.b, Rel.w.c); 1284 } 1285 1286 template<support::endianness target_endianness, bool is64Bits> 1287 const typename ELFObjectFile<target_endianness, is64Bits>::Elf_Rela * 1288 ELFObjectFile<target_endianness, is64Bits>::getRela(DataRefImpl Rela) const { 1289 return getEntry<Elf_Rela>(Rela.w.b, Rela.w.c); 1290 } 1291 1292 template<support::endianness target_endianness, bool is64Bits> 1293 const typename ELFObjectFile<target_endianness, is64Bits>::Elf_Shdr * 1294 ELFObjectFile<target_endianness, is64Bits>::getSection(DataRefImpl Symb) const { 1295 const Elf_Shdr *sec = getSection(Symb.d.b); 1296 if (sec->sh_type != ELF::SHT_SYMTAB || sec->sh_type != ELF::SHT_DYNSYM) 1297 // FIXME: Proper error handling. 1298 report_fatal_error("Invalid symbol table section!"); 1299 return sec; 1300 } 1301 1302 template<support::endianness target_endianness, bool is64Bits> 1303 const typename ELFObjectFile<target_endianness, is64Bits>::Elf_Shdr * 1304 ELFObjectFile<target_endianness, is64Bits>::getSection(uint16_t index) const { 1305 if (index == 0 || index >= ELF::SHN_LORESERVE) 1306 return 0; 1307 if (!SectionHeaderTable || index >= Header->e_shnum) 1308 // FIXME: Proper error handling. 1309 report_fatal_error("Invalid section index!"); 1310 1311 return reinterpret_cast<const Elf_Shdr *>( 1312 reinterpret_cast<const char *>(SectionHeaderTable) 1313 + (index * Header->e_shentsize)); 1314 } 1315 1316 template<support::endianness target_endianness, bool is64Bits> 1317 const char *ELFObjectFile<target_endianness, is64Bits> 1318 ::getString(uint16_t section, 1319 ELF::Elf32_Word offset) const { 1320 return getString(getSection(section), offset); 1321 } 1322 1323 template<support::endianness target_endianness, bool is64Bits> 1324 const char *ELFObjectFile<target_endianness, is64Bits> 1325 ::getString(const Elf_Shdr *section, 1326 ELF::Elf32_Word offset) const { 1327 assert(section && section->sh_type == ELF::SHT_STRTAB && "Invalid section!"); 1328 if (offset >= section->sh_size) 1329 // FIXME: Proper error handling. 1330 report_fatal_error("Symbol name offset outside of string table!"); 1331 return (const char *)base() + section->sh_offset + offset; 1332 } 1333 1334 template<support::endianness target_endianness, bool is64Bits> 1335 error_code ELFObjectFile<target_endianness, is64Bits> 1336 ::getSymbolName(const Elf_Sym *symb, 1337 StringRef &Result) const { 1338 if (symb->st_name == 0) { 1339 const Elf_Shdr *section = getSection(getSymbolTableIndex(symb)); 1340 if (!section) 1341 Result = ""; 1342 else 1343 Result = getString(dot_shstrtab_sec, section->sh_name); 1344 return object_error::success; 1345 } 1346 1347 // Use the default symbol table name section. 1348 Result = getString(dot_strtab_sec, symb->st_name); 1349 return object_error::success; 1350 } 1351 1352 // EI_CLASS, EI_DATA. 1353 static std::pair<unsigned char, unsigned char> 1354 getElfArchType(MemoryBuffer *Object) { 1355 if (Object->getBufferSize() < ELF::EI_NIDENT) 1356 return std::make_pair((uint8_t)ELF::ELFCLASSNONE,(uint8_t)ELF::ELFDATANONE); 1357 return std::make_pair( (uint8_t)Object->getBufferStart()[ELF::EI_CLASS] 1358 , (uint8_t)Object->getBufferStart()[ELF::EI_DATA]); 1359 } 1360 1361 namespace llvm { 1362 1363 ObjectFile *ObjectFile::createELFObjectFile(MemoryBuffer *Object) { 1364 std::pair<unsigned char, unsigned char> Ident = getElfArchType(Object); 1365 error_code ec; 1366 if (Ident.first == ELF::ELFCLASS32 && Ident.second == ELF::ELFDATA2LSB) 1367 return new ELFObjectFile<support::little, false>(Object, ec); 1368 else if (Ident.first == ELF::ELFCLASS32 && Ident.second == ELF::ELFDATA2MSB) 1369 return new ELFObjectFile<support::big, false>(Object, ec); 1370 else if (Ident.first == ELF::ELFCLASS64 && Ident.second == ELF::ELFDATA2LSB) 1371 return new ELFObjectFile<support::little, true>(Object, ec); 1372 else if (Ident.first == ELF::ELFCLASS64 && Ident.second == ELF::ELFDATA2MSB) 1373 return new ELFObjectFile<support::big, true>(Object, ec); 1374 // FIXME: Proper error handling. 1375 report_fatal_error("Not an ELF object file!"); 1376 } 1377 1378 } // end namespace llvm 1379