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; 299 300 /// @brief Map sections to an array of relocation sections that reference 301 /// them sorted by section index. 302 RelocMap_t SectionRelocMap; 303 304 /// @brief Get the relocation section that contains \a Rel. 305 const Elf_Shdr *getRelSection(DataRefImpl Rel) const { 306 return getSection(Rel.w.b); 307 } 308 309 void validateSymbol(DataRefImpl Symb) const; 310 bool isRelocationHasAddend(DataRefImpl Rel) const; 311 template<typename T> 312 const T *getEntry(uint16_t Section, uint32_t Entry) const; 313 template<typename T> 314 const T *getEntry(const Elf_Shdr *Section, uint32_t Entry) const; 315 const Elf_Sym *getSymbol(DataRefImpl Symb) const; 316 const Elf_Shdr *getSection(DataRefImpl index) const; 317 const Elf_Shdr *getSection(uint16_t index) const; 318 const Elf_Rel *getRel(DataRefImpl Rel) const; 319 const Elf_Rela *getRela(DataRefImpl Rela) const; 320 const char *getString(uint16_t section, uint32_t offset) const; 321 const char *getString(const Elf_Shdr *section, uint32_t offset) const; 322 error_code getSymbolName(const Elf_Sym *Symb, StringRef &Res) const; 323 324 protected: 325 virtual error_code getSymbolNext(DataRefImpl Symb, SymbolRef &Res) const; 326 virtual error_code getSymbolName(DataRefImpl Symb, StringRef &Res) const; 327 virtual error_code getSymbolOffset(DataRefImpl Symb, uint64_t &Res) const; 328 virtual error_code getSymbolAddress(DataRefImpl Symb, uint64_t &Res) const; 329 virtual error_code getSymbolSize(DataRefImpl Symb, uint64_t &Res) const; 330 virtual error_code getSymbolNMTypeChar(DataRefImpl Symb, char &Res) const; 331 virtual error_code isSymbolInternal(DataRefImpl Symb, bool &Res) const; 332 virtual error_code isSymbolGlobal(DataRefImpl Symb, bool &Res) const; 333 virtual error_code getSymbolType(DataRefImpl Symb, SymbolRef::SymbolType &Res) const; 334 335 virtual error_code getSectionNext(DataRefImpl Sec, SectionRef &Res) const; 336 virtual error_code getSectionName(DataRefImpl Sec, StringRef &Res) const; 337 virtual error_code getSectionAddress(DataRefImpl Sec, uint64_t &Res) const; 338 virtual error_code getSectionSize(DataRefImpl Sec, uint64_t &Res) const; 339 virtual error_code getSectionContents(DataRefImpl Sec, StringRef &Res) const; 340 virtual error_code getSectionAlignment(DataRefImpl Sec, uint64_t &Res) const; 341 virtual error_code isSectionText(DataRefImpl Sec, bool &Res) const; 342 virtual error_code isSectionData(DataRefImpl Sec, bool &Res) const; 343 virtual error_code isSectionBSS(DataRefImpl Sec, bool &Res) const; 344 virtual error_code sectionContainsSymbol(DataRefImpl Sec, DataRefImpl Symb, 345 bool &Result) const; 346 virtual relocation_iterator getSectionRelBegin(DataRefImpl Sec) const; 347 virtual relocation_iterator getSectionRelEnd(DataRefImpl Sec) const; 348 349 virtual error_code getRelocationNext(DataRefImpl Rel, 350 RelocationRef &Res) const; 351 virtual error_code getRelocationAddress(DataRefImpl Rel, 352 uint64_t &Res) const; 353 virtual error_code getRelocationSymbol(DataRefImpl Rel, 354 SymbolRef &Res) const; 355 virtual error_code getRelocationType(DataRefImpl Rel, 356 uint32_t &Res) const; 357 virtual error_code getRelocationTypeName(DataRefImpl Rel, 358 SmallVectorImpl<char> &Result) const; 359 virtual error_code getRelocationAdditionalInfo(DataRefImpl Rel, 360 int64_t &Res) const; 361 virtual error_code getRelocationValueString(DataRefImpl Rel, 362 SmallVectorImpl<char> &Result) const; 363 364 public: 365 ELFObjectFile(MemoryBuffer *Object, error_code &ec); 366 virtual symbol_iterator begin_symbols() const; 367 virtual symbol_iterator end_symbols() const; 368 virtual section_iterator begin_sections() const; 369 virtual section_iterator end_sections() const; 370 371 virtual uint8_t getBytesInAddress() const; 372 virtual StringRef getFileFormatName() const; 373 virtual unsigned getArch() const; 374 }; 375 } // end namespace 376 377 template<support::endianness target_endianness, bool is64Bits> 378 void ELFObjectFile<target_endianness, is64Bits> 379 ::validateSymbol(DataRefImpl Symb) const { 380 const Elf_Sym *symb = getSymbol(Symb); 381 const Elf_Shdr *SymbolTableSection = SymbolTableSections[Symb.d.b]; 382 // FIXME: We really need to do proper error handling in the case of an invalid 383 // input file. Because we don't use exceptions, I think we'll just pass 384 // an error object around. 385 if (!( symb 386 && SymbolTableSection 387 && symb >= (const Elf_Sym*)(base() 388 + SymbolTableSection->sh_offset) 389 && symb < (const Elf_Sym*)(base() 390 + SymbolTableSection->sh_offset 391 + SymbolTableSection->sh_size))) 392 // FIXME: Proper error handling. 393 report_fatal_error("Symb must point to a valid symbol!"); 394 } 395 396 template<support::endianness target_endianness, bool is64Bits> 397 error_code ELFObjectFile<target_endianness, is64Bits> 398 ::getSymbolNext(DataRefImpl Symb, 399 SymbolRef &Result) const { 400 validateSymbol(Symb); 401 const Elf_Shdr *SymbolTableSection = SymbolTableSections[Symb.d.b]; 402 403 ++Symb.d.a; 404 // Check to see if we are at the end of this symbol table. 405 if (Symb.d.a >= SymbolTableSection->getEntityCount()) { 406 // We are at the end. If there are other symbol tables, jump to them. 407 ++Symb.d.b; 408 Symb.d.a = 1; // The 0th symbol in ELF is fake. 409 // Otherwise return the terminator. 410 if (Symb.d.b >= SymbolTableSections.size()) { 411 Symb.d.a = std::numeric_limits<uint32_t>::max(); 412 Symb.d.b = std::numeric_limits<uint32_t>::max(); 413 } 414 } 415 416 Result = SymbolRef(Symb, this); 417 return object_error::success; 418 } 419 420 template<support::endianness target_endianness, bool is64Bits> 421 error_code ELFObjectFile<target_endianness, is64Bits> 422 ::getSymbolName(DataRefImpl Symb, 423 StringRef &Result) const { 424 validateSymbol(Symb); 425 const Elf_Sym *symb = getSymbol(Symb); 426 return getSymbolName(symb, Result); 427 } 428 429 template<support::endianness target_endianness, bool is64Bits> 430 error_code ELFObjectFile<target_endianness, is64Bits> 431 ::getSymbolOffset(DataRefImpl Symb, 432 uint64_t &Result) const { 433 validateSymbol(Symb); 434 const Elf_Sym *symb = getSymbol(Symb); 435 const Elf_Shdr *Section; 436 switch (symb->st_shndx) { 437 case ELF::SHN_COMMON: 438 // Undefined symbols have no address yet. 439 case ELF::SHN_UNDEF: 440 Result = UnknownAddressOrSize; 441 return object_error::success; 442 case ELF::SHN_ABS: 443 Result = symb->st_value; 444 return object_error::success; 445 default: Section = getSection(symb->st_shndx); 446 } 447 448 switch (symb->getType()) { 449 case ELF::STT_SECTION: 450 Result = Section ? Section->sh_addr : UnknownAddressOrSize; 451 return object_error::success; 452 case ELF::STT_FUNC: 453 case ELF::STT_OBJECT: 454 case ELF::STT_NOTYPE: 455 Result = symb->st_value; 456 return object_error::success; 457 default: 458 Result = UnknownAddressOrSize; 459 return object_error::success; 460 } 461 } 462 463 template<support::endianness target_endianness, bool is64Bits> 464 error_code ELFObjectFile<target_endianness, is64Bits> 465 ::getSymbolAddress(DataRefImpl Symb, 466 uint64_t &Result) const { 467 validateSymbol(Symb); 468 const Elf_Sym *symb = getSymbol(Symb); 469 const Elf_Shdr *Section; 470 switch (symb->st_shndx) { 471 case ELF::SHN_COMMON: // Fall through. 472 // Undefined symbols have no address yet. 473 case ELF::SHN_UNDEF: 474 Result = UnknownAddressOrSize; 475 return object_error::success; 476 case ELF::SHN_ABS: 477 Result = reinterpret_cast<uintptr_t>(base()+symb->st_value); 478 return object_error::success; 479 default: Section = getSection(symb->st_shndx); 480 } 481 const uint8_t* addr = base(); 482 if (Section) 483 addr += Section->sh_offset; 484 switch (symb->getType()) { 485 case ELF::STT_SECTION: 486 Result = reinterpret_cast<uintptr_t>(addr); 487 return object_error::success; 488 case ELF::STT_FUNC: // Fall through. 489 case ELF::STT_OBJECT: // Fall through. 490 case ELF::STT_NOTYPE: 491 addr += symb->st_value; 492 Result = reinterpret_cast<uintptr_t>(addr); 493 return object_error::success; 494 default: 495 Result = UnknownAddressOrSize; 496 return object_error::success; 497 } 498 } 499 500 template<support::endianness target_endianness, bool is64Bits> 501 error_code ELFObjectFile<target_endianness, is64Bits> 502 ::getSymbolSize(DataRefImpl Symb, 503 uint64_t &Result) const { 504 validateSymbol(Symb); 505 const Elf_Sym *symb = getSymbol(Symb); 506 if (symb->st_size == 0) 507 Result = UnknownAddressOrSize; 508 Result = symb->st_size; 509 return object_error::success; 510 } 511 512 template<support::endianness target_endianness, bool is64Bits> 513 error_code ELFObjectFile<target_endianness, is64Bits> 514 ::getSymbolNMTypeChar(DataRefImpl Symb, 515 char &Result) const { 516 validateSymbol(Symb); 517 const Elf_Sym *symb = getSymbol(Symb); 518 const Elf_Shdr *Section = getSection(symb->st_shndx); 519 520 char ret = '?'; 521 522 if (Section) { 523 switch (Section->sh_type) { 524 case ELF::SHT_PROGBITS: 525 case ELF::SHT_DYNAMIC: 526 switch (Section->sh_flags) { 527 case (ELF::SHF_ALLOC | ELF::SHF_EXECINSTR): 528 ret = 't'; break; 529 case (ELF::SHF_ALLOC | ELF::SHF_WRITE): 530 ret = 'd'; break; 531 case ELF::SHF_ALLOC: 532 case (ELF::SHF_ALLOC | ELF::SHF_MERGE): 533 case (ELF::SHF_ALLOC | ELF::SHF_MERGE | ELF::SHF_STRINGS): 534 ret = 'r'; break; 535 } 536 break; 537 case ELF::SHT_NOBITS: ret = 'b'; 538 } 539 } 540 541 switch (symb->st_shndx) { 542 case ELF::SHN_UNDEF: 543 if (ret == '?') 544 ret = 'U'; 545 break; 546 case ELF::SHN_ABS: ret = 'a'; break; 547 case ELF::SHN_COMMON: ret = 'c'; break; 548 } 549 550 switch (symb->getBinding()) { 551 case ELF::STB_GLOBAL: ret = ::toupper(ret); break; 552 case ELF::STB_WEAK: 553 if (symb->st_shndx == ELF::SHN_UNDEF) 554 ret = 'w'; 555 else 556 if (symb->getType() == ELF::STT_OBJECT) 557 ret = 'V'; 558 else 559 ret = 'W'; 560 } 561 562 if (ret == '?' && symb->getType() == ELF::STT_SECTION) { 563 StringRef name; 564 if (error_code ec = getSymbolName(Symb, name)) 565 return ec; 566 Result = StringSwitch<char>(name) 567 .StartsWith(".debug", 'N') 568 .StartsWith(".note", 'n') 569 .Default('?'); 570 return object_error::success; 571 } 572 573 Result = ret; 574 return object_error::success; 575 } 576 577 template<support::endianness target_endianness, bool is64Bits> 578 error_code ELFObjectFile<target_endianness, is64Bits> 579 ::getSymbolType(DataRefImpl Symb, 580 SymbolRef::SymbolType &Result) const { 581 validateSymbol(Symb); 582 const Elf_Sym *symb = getSymbol(Symb); 583 584 if (symb->st_shndx == ELF::SHN_UNDEF) { 585 Result = SymbolRef::ST_External; 586 return object_error::success; 587 } 588 589 switch (symb->getType()) { 590 case ELF::STT_FUNC: 591 Result = SymbolRef::ST_Function; 592 break; 593 case ELF::STT_OBJECT: 594 Result = SymbolRef::ST_Data; 595 break; 596 default: 597 Result = SymbolRef::ST_Other; 598 break; 599 } 600 return object_error::success; 601 } 602 603 template<support::endianness target_endianness, bool is64Bits> 604 error_code ELFObjectFile<target_endianness, is64Bits> 605 ::isSymbolGlobal(DataRefImpl Symb, 606 bool &Result) const { 607 validateSymbol(Symb); 608 const Elf_Sym *symb = getSymbol(Symb); 609 610 Result = symb->getBinding() == ELF::STB_GLOBAL; 611 return object_error::success; 612 } 613 614 template<support::endianness target_endianness, bool is64Bits> 615 error_code ELFObjectFile<target_endianness, is64Bits> 616 ::isSymbolInternal(DataRefImpl Symb, 617 bool &Result) const { 618 validateSymbol(Symb); 619 const Elf_Sym *symb = getSymbol(Symb); 620 621 if ( symb->getType() == ELF::STT_FILE 622 || symb->getType() == ELF::STT_SECTION) 623 Result = true; 624 Result = false; 625 return object_error::success; 626 } 627 628 template<support::endianness target_endianness, bool is64Bits> 629 error_code ELFObjectFile<target_endianness, is64Bits> 630 ::getSectionNext(DataRefImpl Sec, SectionRef &Result) const { 631 const uint8_t *sec = reinterpret_cast<const uint8_t *>(Sec.p); 632 sec += Header->e_shentsize; 633 Sec.p = reinterpret_cast<intptr_t>(sec); 634 Result = SectionRef(Sec, this); 635 return object_error::success; 636 } 637 638 template<support::endianness target_endianness, bool is64Bits> 639 error_code ELFObjectFile<target_endianness, is64Bits> 640 ::getSectionName(DataRefImpl Sec, 641 StringRef &Result) const { 642 const Elf_Shdr *sec = reinterpret_cast<const Elf_Shdr *>(Sec.p); 643 Result = StringRef(getString(dot_shstrtab_sec, sec->sh_name)); 644 return object_error::success; 645 } 646 647 template<support::endianness target_endianness, bool is64Bits> 648 error_code ELFObjectFile<target_endianness, is64Bits> 649 ::getSectionAddress(DataRefImpl Sec, 650 uint64_t &Result) const { 651 const Elf_Shdr *sec = reinterpret_cast<const Elf_Shdr *>(Sec.p); 652 Result = sec->sh_addr; 653 return object_error::success; 654 } 655 656 template<support::endianness target_endianness, bool is64Bits> 657 error_code ELFObjectFile<target_endianness, is64Bits> 658 ::getSectionSize(DataRefImpl Sec, 659 uint64_t &Result) const { 660 const Elf_Shdr *sec = reinterpret_cast<const Elf_Shdr *>(Sec.p); 661 Result = sec->sh_size; 662 return object_error::success; 663 } 664 665 template<support::endianness target_endianness, bool is64Bits> 666 error_code ELFObjectFile<target_endianness, is64Bits> 667 ::getSectionContents(DataRefImpl Sec, 668 StringRef &Result) const { 669 const Elf_Shdr *sec = reinterpret_cast<const Elf_Shdr *>(Sec.p); 670 const char *start = (const char*)base() + sec->sh_offset; 671 Result = StringRef(start, sec->sh_size); 672 return object_error::success; 673 } 674 675 template<support::endianness target_endianness, bool is64Bits> 676 error_code ELFObjectFile<target_endianness, is64Bits> 677 ::getSectionAlignment(DataRefImpl Sec, 678 uint64_t &Result) const { 679 const Elf_Shdr *sec = reinterpret_cast<const Elf_Shdr *>(Sec.p); 680 Result = sec->sh_addralign; 681 return object_error::success; 682 } 683 684 template<support::endianness target_endianness, bool is64Bits> 685 error_code ELFObjectFile<target_endianness, is64Bits> 686 ::isSectionText(DataRefImpl Sec, 687 bool &Result) const { 688 const Elf_Shdr *sec = reinterpret_cast<const Elf_Shdr *>(Sec.p); 689 if (sec->sh_flags & ELF::SHF_EXECINSTR) 690 Result = true; 691 else 692 Result = false; 693 return object_error::success; 694 } 695 696 template<support::endianness target_endianness, bool is64Bits> 697 error_code ELFObjectFile<target_endianness, is64Bits> 698 ::isSectionData(DataRefImpl Sec, 699 bool &Result) const { 700 const Elf_Shdr *sec = reinterpret_cast<const Elf_Shdr *>(Sec.p); 701 if (sec->sh_flags & (ELF::SHF_ALLOC | ELF::SHF_WRITE) 702 && sec->sh_type == ELF::SHT_PROGBITS) 703 Result = true; 704 else 705 Result = false; 706 return object_error::success; 707 } 708 709 template<support::endianness target_endianness, bool is64Bits> 710 error_code ELFObjectFile<target_endianness, is64Bits> 711 ::isSectionBSS(DataRefImpl Sec, 712 bool &Result) const { 713 const Elf_Shdr *sec = reinterpret_cast<const Elf_Shdr *>(Sec.p); 714 if (sec->sh_flags & (ELF::SHF_ALLOC | ELF::SHF_WRITE) 715 && sec->sh_type == ELF::SHT_NOBITS) 716 Result = true; 717 else 718 Result = false; 719 return object_error::success; 720 } 721 722 template<support::endianness target_endianness, bool is64Bits> 723 error_code ELFObjectFile<target_endianness, is64Bits> 724 ::sectionContainsSymbol(DataRefImpl Sec, 725 DataRefImpl Symb, 726 bool &Result) const { 727 // FIXME: Unimplemented. 728 Result = false; 729 return object_error::success; 730 } 731 732 template<support::endianness target_endianness, bool is64Bits> 733 relocation_iterator ELFObjectFile<target_endianness, is64Bits> 734 ::getSectionRelBegin(DataRefImpl Sec) const { 735 DataRefImpl RelData; 736 memset(&RelData, 0, sizeof(RelData)); 737 const Elf_Shdr *sec = reinterpret_cast<const Elf_Shdr *>(Sec.p); 738 typename RelocMap_t::const_iterator ittr = SectionRelocMap.find(sec); 739 if (sec != 0 && ittr != SectionRelocMap.end()) { 740 RelData.w.a = getSection(ittr->second[0])->sh_link; 741 RelData.w.b = ittr->second[0]; 742 RelData.w.c = 0; 743 } 744 return relocation_iterator(RelocationRef(RelData, this)); 745 } 746 747 template<support::endianness target_endianness, bool is64Bits> 748 relocation_iterator ELFObjectFile<target_endianness, is64Bits> 749 ::getSectionRelEnd(DataRefImpl Sec) const { 750 DataRefImpl RelData; 751 memset(&RelData, 0, sizeof(RelData)); 752 const Elf_Shdr *sec = reinterpret_cast<const Elf_Shdr *>(Sec.p); 753 typename RelocMap_t::const_iterator ittr = SectionRelocMap.find(sec); 754 if (sec != 0 && ittr != SectionRelocMap.end()) { 755 // Get the index of the last relocation section for this section. 756 std::size_t relocsecindex = ittr->second[ittr->second.size() - 1]; 757 const Elf_Shdr *relocsec = getSection(relocsecindex); 758 RelData.w.a = relocsec->sh_link; 759 RelData.w.b = relocsecindex; 760 RelData.w.c = relocsec->sh_size / relocsec->sh_entsize; 761 } 762 return relocation_iterator(RelocationRef(RelData, this)); 763 } 764 765 // Relocations 766 template<support::endianness target_endianness, bool is64Bits> 767 error_code ELFObjectFile<target_endianness, is64Bits> 768 ::getRelocationNext(DataRefImpl Rel, 769 RelocationRef &Result) const { 770 ++Rel.w.c; 771 const Elf_Shdr *relocsec = getSection(Rel.w.b); 772 if (Rel.w.c >= (relocsec->sh_size / relocsec->sh_entsize)) { 773 // We have reached the end of the relocations for this section. See if there 774 // is another relocation section. 775 typename RelocMap_t::mapped_type relocseclist = 776 SectionRelocMap.lookup(getSection(Rel.w.a)); 777 778 // Do a binary search for the current reloc section index (which must be 779 // present). Then get the next one. 780 typename RelocMap_t::mapped_type::const_iterator loc = 781 std::lower_bound(relocseclist.begin(), relocseclist.end(), Rel.w.b); 782 ++loc; 783 784 // If there is no next one, don't do anything. The ++Rel.w.c above sets Rel 785 // to the end iterator. 786 if (loc != relocseclist.end()) { 787 Rel.w.b = *loc; 788 Rel.w.a = 0; 789 } 790 } 791 Result = RelocationRef(Rel, this); 792 return object_error::success; 793 } 794 795 template<support::endianness target_endianness, bool is64Bits> 796 error_code ELFObjectFile<target_endianness, is64Bits> 797 ::getRelocationSymbol(DataRefImpl Rel, 798 SymbolRef &Result) const { 799 uint32_t symbolIdx; 800 const Elf_Shdr *sec = getSection(Rel.w.b); 801 switch (sec->sh_type) { 802 default : 803 report_fatal_error("Invalid section type in Rel!"); 804 case ELF::SHT_REL : { 805 symbolIdx = getRel(Rel)->getSymbol(); 806 break; 807 } 808 case ELF::SHT_RELA : { 809 symbolIdx = getRela(Rel)->getSymbol(); 810 break; 811 } 812 } 813 DataRefImpl SymbolData; 814 IndexMap_t::const_iterator it = SymbolTableSectionsIndexMap.find(sec->sh_link); 815 if (it == SymbolTableSectionsIndexMap.end()) 816 report_fatal_error("Relocation symbol table not found!"); 817 SymbolData.d.a = symbolIdx; 818 SymbolData.d.b = it->second; 819 Result = SymbolRef(SymbolData, this); 820 return object_error::success; 821 } 822 823 template<support::endianness target_endianness, bool is64Bits> 824 error_code ELFObjectFile<target_endianness, is64Bits> 825 ::getRelocationAddress(DataRefImpl Rel, 826 uint64_t &Result) const { 827 uint64_t offset; 828 const Elf_Shdr *sec = getSection(Rel.w.b); 829 switch (sec->sh_type) { 830 default : 831 report_fatal_error("Invalid section type in Rel!"); 832 case ELF::SHT_REL : { 833 offset = getRel(Rel)->r_offset; 834 break; 835 } 836 case ELF::SHT_RELA : { 837 offset = getRela(Rel)->r_offset; 838 break; 839 } 840 } 841 842 Result = offset; 843 return object_error::success; 844 } 845 846 template<support::endianness target_endianness, bool is64Bits> 847 error_code ELFObjectFile<target_endianness, is64Bits> 848 ::getRelocationType(DataRefImpl Rel, 849 uint32_t &Result) const { 850 const Elf_Shdr *sec = getSection(Rel.w.b); 851 switch (sec->sh_type) { 852 default : 853 report_fatal_error("Invalid section type in Rel!"); 854 case ELF::SHT_REL : { 855 Result = getRel(Rel)->getType(); 856 break; 857 } 858 case ELF::SHT_RELA : { 859 Result = getRela(Rel)->getType(); 860 break; 861 } 862 } 863 return object_error::success; 864 } 865 866 #define LLVM_ELF_SWITCH_RELOC_TYPE_NAME(enum) \ 867 case ELF::enum: res = #enum; break; 868 869 template<support::endianness target_endianness, bool is64Bits> 870 error_code ELFObjectFile<target_endianness, is64Bits> 871 ::getRelocationTypeName(DataRefImpl Rel, 872 SmallVectorImpl<char> &Result) const { 873 const Elf_Shdr *sec = getSection(Rel.w.b); 874 uint8_t type; 875 StringRef res; 876 switch (sec->sh_type) { 877 default : 878 return object_error::parse_failed; 879 case ELF::SHT_REL : { 880 type = getRel(Rel)->getType(); 881 break; 882 } 883 case ELF::SHT_RELA : { 884 type = getRela(Rel)->getType(); 885 break; 886 } 887 } 888 switch (Header->e_machine) { 889 case ELF::EM_X86_64: 890 switch (type) { 891 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_NONE); 892 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_64); 893 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_PC32); 894 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_GOT32); 895 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_PLT32); 896 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_COPY); 897 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_GLOB_DAT); 898 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_JUMP_SLOT); 899 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_RELATIVE); 900 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_GOTPCREL); 901 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_32); 902 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_32S); 903 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_16); 904 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_PC16); 905 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_8); 906 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_PC8); 907 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_DTPMOD64); 908 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_DTPOFF64); 909 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_TPOFF64); 910 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_TLSGD); 911 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_TLSLD); 912 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_DTPOFF32); 913 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_GOTTPOFF); 914 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_TPOFF32); 915 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_PC64); 916 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_GOTOFF64); 917 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_GOTPC32); 918 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_SIZE32); 919 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_SIZE64); 920 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_GOTPC32_TLSDESC); 921 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_TLSDESC_CALL); 922 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_X86_64_TLSDESC); 923 default: 924 res = "Unknown"; 925 } 926 break; 927 case ELF::EM_386: 928 switch (type) { 929 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_NONE); 930 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_32); 931 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_PC32); 932 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_GOT32); 933 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_PLT32); 934 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_COPY); 935 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_GLOB_DAT); 936 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_JUMP_SLOT); 937 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_RELATIVE); 938 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_GOTOFF); 939 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_GOTPC); 940 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_32PLT); 941 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_TPOFF); 942 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_IE); 943 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_GOTIE); 944 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_LE); 945 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_GD); 946 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_LDM); 947 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_16); 948 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_PC16); 949 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_8); 950 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_PC8); 951 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_GD_32); 952 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_GD_PUSH); 953 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_GD_CALL); 954 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_GD_POP); 955 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_LDM_32); 956 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_LDM_PUSH); 957 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_LDM_CALL); 958 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_LDM_POP); 959 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_LDO_32); 960 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_IE_32); 961 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_LE_32); 962 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_DTPMOD32); 963 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_DTPOFF32); 964 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_TPOFF32); 965 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_GOTDESC); 966 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_DESC_CALL); 967 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_TLS_DESC); 968 LLVM_ELF_SWITCH_RELOC_TYPE_NAME(R_386_IRELATIVE); 969 default: 970 res = "Unknown"; 971 } 972 break; 973 default: 974 res = "Unknown"; 975 } 976 Result.append(res.begin(), res.end()); 977 return object_error::success; 978 } 979 980 #undef LLVM_ELF_SWITCH_RELOC_TYPE_NAME 981 982 template<support::endianness target_endianness, bool is64Bits> 983 error_code ELFObjectFile<target_endianness, is64Bits> 984 ::getRelocationAdditionalInfo(DataRefImpl Rel, 985 int64_t &Result) const { 986 const Elf_Shdr *sec = getSection(Rel.w.b); 987 switch (sec->sh_type) { 988 default : 989 report_fatal_error("Invalid section type in Rel!"); 990 case ELF::SHT_REL : { 991 Result = 0; 992 return object_error::success; 993 } 994 case ELF::SHT_RELA : { 995 Result = getRela(Rel)->r_addend; 996 return object_error::success; 997 } 998 } 999 } 1000 1001 template<support::endianness target_endianness, bool is64Bits> 1002 error_code ELFObjectFile<target_endianness, is64Bits> 1003 ::getRelocationValueString(DataRefImpl Rel, 1004 SmallVectorImpl<char> &Result) const { 1005 const Elf_Shdr *sec = getSection(Rel.w.b); 1006 uint8_t type; 1007 StringRef res; 1008 int64_t addend = 0; 1009 uint16_t symbol_index = 0; 1010 switch (sec->sh_type) { 1011 default : 1012 return object_error::parse_failed; 1013 case ELF::SHT_REL : { 1014 type = getRel(Rel)->getType(); 1015 symbol_index = getRel(Rel)->getSymbol(); 1016 // TODO: Read implicit addend from section data. 1017 break; 1018 } 1019 case ELF::SHT_RELA : { 1020 type = getRela(Rel)->getType(); 1021 symbol_index = getRela(Rel)->getSymbol(); 1022 addend = getRela(Rel)->r_addend; 1023 break; 1024 } 1025 } 1026 const Elf_Sym *symb = getEntry<Elf_Sym>(sec->sh_link, symbol_index); 1027 StringRef symname; 1028 if (error_code ec = getSymbolName(symb, symname)) 1029 return ec; 1030 switch (Header->e_machine) { 1031 case ELF::EM_X86_64: 1032 switch (type) { 1033 case ELF::R_X86_64_32S: 1034 res = symname; 1035 break; 1036 case ELF::R_X86_64_PC32: { 1037 std::string fmtbuf; 1038 raw_string_ostream fmt(fmtbuf); 1039 fmt << symname << (addend < 0 ? "" : "+") << addend << "-P"; 1040 fmt.flush(); 1041 Result.append(fmtbuf.begin(), fmtbuf.end()); 1042 } 1043 break; 1044 default: 1045 res = "Unknown"; 1046 } 1047 break; 1048 default: 1049 res = "Unknown"; 1050 } 1051 if (Result.empty()) 1052 Result.append(res.begin(), res.end()); 1053 return object_error::success; 1054 } 1055 1056 template<support::endianness target_endianness, bool is64Bits> 1057 ELFObjectFile<target_endianness, is64Bits>::ELFObjectFile(MemoryBuffer *Object 1058 , error_code &ec) 1059 : ObjectFile(Binary::isELF, Object, ec) 1060 , SectionHeaderTable(0) 1061 , dot_shstrtab_sec(0) 1062 , dot_strtab_sec(0) { 1063 Header = reinterpret_cast<const Elf_Ehdr *>(base()); 1064 1065 if (Header->e_shoff == 0) 1066 return; 1067 1068 SectionHeaderTable = 1069 reinterpret_cast<const Elf_Shdr *>(base() + Header->e_shoff); 1070 uint32_t SectionTableSize = Header->e_shnum * Header->e_shentsize; 1071 if (!( (const uint8_t *)SectionHeaderTable + SectionTableSize 1072 <= base() + Data->getBufferSize())) 1073 // FIXME: Proper error handling. 1074 report_fatal_error("Section table goes past end of file!"); 1075 1076 1077 // To find the symbol tables we walk the section table to find SHT_STMTAB. 1078 const Elf_Shdr* sh = reinterpret_cast<const Elf_Shdr*>(SectionHeaderTable); 1079 for (unsigned i = 0; i < Header->e_shnum; ++i) { 1080 if (sh->sh_type == ELF::SHT_SYMTAB) { 1081 SymbolTableSectionsIndexMap[i] = SymbolTableSections.size(); 1082 SymbolTableSections.push_back(sh); 1083 } 1084 if (sh->sh_type == ELF::SHT_REL || sh->sh_type == ELF::SHT_RELA) { 1085 SectionRelocMap[getSection(sh->sh_link)].push_back(i); 1086 } 1087 ++sh; 1088 } 1089 1090 // Sort section relocation lists by index. 1091 for (typename RelocMap_t::iterator i = SectionRelocMap.begin(), 1092 e = SectionRelocMap.end(); i != e; ++i) { 1093 std::sort(i->second.begin(), i->second.end()); 1094 } 1095 1096 // Get string table sections. 1097 dot_shstrtab_sec = getSection(Header->e_shstrndx); 1098 if (dot_shstrtab_sec) { 1099 // Verify that the last byte in the string table in a null. 1100 if (((const char*)base() + dot_shstrtab_sec->sh_offset) 1101 [dot_shstrtab_sec->sh_size - 1] != 0) 1102 // FIXME: Proper error handling. 1103 report_fatal_error("String table must end with a null terminator!"); 1104 } 1105 1106 // Merge this into the above loop. 1107 for (const char *i = reinterpret_cast<const char *>(SectionHeaderTable), 1108 *e = i + Header->e_shnum * Header->e_shentsize; 1109 i != e; i += Header->e_shentsize) { 1110 const Elf_Shdr *sh = reinterpret_cast<const Elf_Shdr*>(i); 1111 if (sh->sh_type == ELF::SHT_STRTAB) { 1112 StringRef SectionName(getString(dot_shstrtab_sec, sh->sh_name)); 1113 if (SectionName == ".strtab") { 1114 if (dot_strtab_sec != 0) 1115 // FIXME: Proper error handling. 1116 report_fatal_error("Already found section named .strtab!"); 1117 dot_strtab_sec = sh; 1118 const char *dot_strtab = (const char*)base() + sh->sh_offset; 1119 if (dot_strtab[sh->sh_size - 1] != 0) 1120 // FIXME: Proper error handling. 1121 report_fatal_error("String table must end with a null terminator!"); 1122 } 1123 } 1124 } 1125 } 1126 1127 template<support::endianness target_endianness, bool is64Bits> 1128 symbol_iterator ELFObjectFile<target_endianness, is64Bits> 1129 ::begin_symbols() const { 1130 DataRefImpl SymbolData; 1131 memset(&SymbolData, 0, sizeof(SymbolData)); 1132 if (SymbolTableSections.size() == 0) { 1133 SymbolData.d.a = std::numeric_limits<uint32_t>::max(); 1134 SymbolData.d.b = std::numeric_limits<uint32_t>::max(); 1135 } else { 1136 SymbolData.d.a = 1; // The 0th symbol in ELF is fake. 1137 SymbolData.d.b = 0; 1138 } 1139 return symbol_iterator(SymbolRef(SymbolData, this)); 1140 } 1141 1142 template<support::endianness target_endianness, bool is64Bits> 1143 symbol_iterator ELFObjectFile<target_endianness, is64Bits> 1144 ::end_symbols() const { 1145 DataRefImpl SymbolData; 1146 memset(&SymbolData, 0, sizeof(SymbolData)); 1147 SymbolData.d.a = std::numeric_limits<uint32_t>::max(); 1148 SymbolData.d.b = std::numeric_limits<uint32_t>::max(); 1149 return symbol_iterator(SymbolRef(SymbolData, this)); 1150 } 1151 1152 template<support::endianness target_endianness, bool is64Bits> 1153 section_iterator ELFObjectFile<target_endianness, is64Bits> 1154 ::begin_sections() const { 1155 DataRefImpl ret; 1156 memset(&ret, 0, sizeof(DataRefImpl)); 1157 ret.p = reinterpret_cast<intptr_t>(base() + Header->e_shoff); 1158 return section_iterator(SectionRef(ret, this)); 1159 } 1160 1161 template<support::endianness target_endianness, bool is64Bits> 1162 section_iterator ELFObjectFile<target_endianness, is64Bits> 1163 ::end_sections() const { 1164 DataRefImpl ret; 1165 memset(&ret, 0, sizeof(DataRefImpl)); 1166 ret.p = reinterpret_cast<intptr_t>(base() 1167 + Header->e_shoff 1168 + (Header->e_shentsize * Header->e_shnum)); 1169 return section_iterator(SectionRef(ret, this)); 1170 } 1171 1172 template<support::endianness target_endianness, bool is64Bits> 1173 uint8_t ELFObjectFile<target_endianness, is64Bits>::getBytesInAddress() const { 1174 return is64Bits ? 8 : 4; 1175 } 1176 1177 template<support::endianness target_endianness, bool is64Bits> 1178 StringRef ELFObjectFile<target_endianness, is64Bits> 1179 ::getFileFormatName() const { 1180 switch(Header->e_ident[ELF::EI_CLASS]) { 1181 case ELF::ELFCLASS32: 1182 switch(Header->e_machine) { 1183 case ELF::EM_386: 1184 return "ELF32-i386"; 1185 case ELF::EM_X86_64: 1186 return "ELF32-x86-64"; 1187 case ELF::EM_ARM: 1188 return "ELF32-arm"; 1189 default: 1190 return "ELF32-unknown"; 1191 } 1192 case ELF::ELFCLASS64: 1193 switch(Header->e_machine) { 1194 case ELF::EM_386: 1195 return "ELF64-i386"; 1196 case ELF::EM_X86_64: 1197 return "ELF64-x86-64"; 1198 default: 1199 return "ELF64-unknown"; 1200 } 1201 default: 1202 // FIXME: Proper error handling. 1203 report_fatal_error("Invalid ELFCLASS!"); 1204 } 1205 } 1206 1207 template<support::endianness target_endianness, bool is64Bits> 1208 unsigned ELFObjectFile<target_endianness, is64Bits>::getArch() const { 1209 switch(Header->e_machine) { 1210 case ELF::EM_386: 1211 return Triple::x86; 1212 case ELF::EM_X86_64: 1213 return Triple::x86_64; 1214 case ELF::EM_ARM: 1215 return Triple::arm; 1216 default: 1217 return Triple::UnknownArch; 1218 } 1219 } 1220 1221 1222 template<support::endianness target_endianness, bool is64Bits> 1223 template<typename T> 1224 inline const T * 1225 ELFObjectFile<target_endianness, is64Bits>::getEntry(uint16_t Section, 1226 uint32_t Entry) const { 1227 return getEntry<T>(getSection(Section), Entry); 1228 } 1229 1230 template<support::endianness target_endianness, bool is64Bits> 1231 template<typename T> 1232 inline const T * 1233 ELFObjectFile<target_endianness, is64Bits>::getEntry(const Elf_Shdr * Section, 1234 uint32_t Entry) const { 1235 return reinterpret_cast<const T *>( 1236 base() 1237 + Section->sh_offset 1238 + (Entry * Section->sh_entsize)); 1239 } 1240 1241 template<support::endianness target_endianness, bool is64Bits> 1242 const typename ELFObjectFile<target_endianness, is64Bits>::Elf_Sym * 1243 ELFObjectFile<target_endianness, is64Bits>::getSymbol(DataRefImpl Symb) const { 1244 return getEntry<Elf_Sym>(SymbolTableSections[Symb.d.b], Symb.d.a); 1245 } 1246 1247 template<support::endianness target_endianness, bool is64Bits> 1248 const typename ELFObjectFile<target_endianness, is64Bits>::Elf_Rel * 1249 ELFObjectFile<target_endianness, is64Bits>::getRel(DataRefImpl Rel) const { 1250 return getEntry<Elf_Rel>(Rel.w.b, Rel.w.c); 1251 } 1252 1253 template<support::endianness target_endianness, bool is64Bits> 1254 const typename ELFObjectFile<target_endianness, is64Bits>::Elf_Rela * 1255 ELFObjectFile<target_endianness, is64Bits>::getRela(DataRefImpl Rela) const { 1256 return getEntry<Elf_Rela>(Rela.w.b, Rela.w.c); 1257 } 1258 1259 template<support::endianness target_endianness, bool is64Bits> 1260 const typename ELFObjectFile<target_endianness, is64Bits>::Elf_Shdr * 1261 ELFObjectFile<target_endianness, is64Bits>::getSection(DataRefImpl Symb) const { 1262 const Elf_Shdr *sec = getSection(Symb.d.b); 1263 if (sec->sh_type != ELF::SHT_SYMTAB || sec->sh_type != ELF::SHT_DYNSYM) 1264 // FIXME: Proper error handling. 1265 report_fatal_error("Invalid symbol table section!"); 1266 return sec; 1267 } 1268 1269 template<support::endianness target_endianness, bool is64Bits> 1270 const typename ELFObjectFile<target_endianness, is64Bits>::Elf_Shdr * 1271 ELFObjectFile<target_endianness, is64Bits>::getSection(uint16_t index) const { 1272 if (index == 0 || index >= ELF::SHN_LORESERVE) 1273 return 0; 1274 if (!SectionHeaderTable || index >= Header->e_shnum) 1275 // FIXME: Proper error handling. 1276 report_fatal_error("Invalid section index!"); 1277 1278 return reinterpret_cast<const Elf_Shdr *>( 1279 reinterpret_cast<const char *>(SectionHeaderTable) 1280 + (index * Header->e_shentsize)); 1281 } 1282 1283 template<support::endianness target_endianness, bool is64Bits> 1284 const char *ELFObjectFile<target_endianness, is64Bits> 1285 ::getString(uint16_t section, 1286 ELF::Elf32_Word offset) const { 1287 return getString(getSection(section), offset); 1288 } 1289 1290 template<support::endianness target_endianness, bool is64Bits> 1291 const char *ELFObjectFile<target_endianness, is64Bits> 1292 ::getString(const Elf_Shdr *section, 1293 ELF::Elf32_Word offset) const { 1294 assert(section && section->sh_type == ELF::SHT_STRTAB && "Invalid section!"); 1295 if (offset >= section->sh_size) 1296 // FIXME: Proper error handling. 1297 report_fatal_error("Symbol name offset outside of string table!"); 1298 return (const char *)base() + section->sh_offset + offset; 1299 } 1300 1301 template<support::endianness target_endianness, bool is64Bits> 1302 error_code ELFObjectFile<target_endianness, is64Bits> 1303 ::getSymbolName(const Elf_Sym *symb, 1304 StringRef &Result) const { 1305 if (symb->st_name == 0) { 1306 const Elf_Shdr *section = getSection(symb->st_shndx); 1307 if (!section) 1308 Result = ""; 1309 else 1310 Result = getString(dot_shstrtab_sec, section->sh_name); 1311 return object_error::success; 1312 } 1313 1314 // Use the default symbol table name section. 1315 Result = getString(dot_strtab_sec, symb->st_name); 1316 return object_error::success; 1317 } 1318 1319 // EI_CLASS, EI_DATA. 1320 static std::pair<unsigned char, unsigned char> 1321 getElfArchType(MemoryBuffer *Object) { 1322 if (Object->getBufferSize() < ELF::EI_NIDENT) 1323 return std::make_pair((uint8_t)ELF::ELFCLASSNONE,(uint8_t)ELF::ELFDATANONE); 1324 return std::make_pair( (uint8_t)Object->getBufferStart()[ELF::EI_CLASS] 1325 , (uint8_t)Object->getBufferStart()[ELF::EI_DATA]); 1326 } 1327 1328 namespace llvm { 1329 1330 ObjectFile *ObjectFile::createELFObjectFile(MemoryBuffer *Object) { 1331 std::pair<unsigned char, unsigned char> Ident = getElfArchType(Object); 1332 error_code ec; 1333 if (Ident.first == ELF::ELFCLASS32 && Ident.second == ELF::ELFDATA2LSB) 1334 return new ELFObjectFile<support::little, false>(Object, ec); 1335 else if (Ident.first == ELF::ELFCLASS32 && Ident.second == ELF::ELFDATA2MSB) 1336 return new ELFObjectFile<support::big, false>(Object, ec); 1337 else if (Ident.first == ELF::ELFCLASS64 && Ident.second == ELF::ELFDATA2LSB) 1338 return new ELFObjectFile<support::little, true>(Object, ec); 1339 else if (Ident.first == ELF::ELFCLASS64 && Ident.second == ELF::ELFDATA2MSB) 1340 return new ELFObjectFile<support::big, true>(Object, ec); 1341 // FIXME: Proper error handling. 1342 report_fatal_error("Not an ELF object file!"); 1343 } 1344 1345 } // end namespace llvm 1346