1 //===- ELFTypes.h - Endian specific types for ELF ---------------*- 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 #ifndef LLVM_OBJECT_ELF_TYPES_H 11 #define LLVM_OBJECT_ELF_TYPES_H 12 13 #include "llvm/Support/AlignOf.h" 14 #include "llvm/Support/DataTypes.h" 15 #include "llvm/Support/ELF.h" 16 #include "llvm/Support/Endian.h" 17 18 namespace llvm { 19 namespace object { 20 21 using support::endianness; 22 23 template <endianness target_endianness, std::size_t max_alignment, 24 bool is64Bits> 25 struct ELFType { 26 static const endianness TargetEndianness = target_endianness; 27 static const std::size_t MaxAlignment = max_alignment; 28 static const bool Is64Bits = is64Bits; 29 }; 30 31 template <typename T, int max_align> struct MaximumAlignment { 32 enum { value = AlignOf<T>::Alignment > max_align ? max_align 33 : AlignOf<T>::Alignment 34 }; 35 }; 36 37 // Templates to choose Elf_Addr and Elf_Off depending on is64Bits. 38 template <endianness target_endianness, std::size_t max_alignment> 39 struct ELFDataTypeTypedefHelperCommon { 40 typedef support::detail::packed_endian_specific_integral< 41 uint16_t, target_endianness, 42 MaximumAlignment<uint16_t, max_alignment>::value> Elf_Half; 43 typedef support::detail::packed_endian_specific_integral< 44 uint32_t, target_endianness, 45 MaximumAlignment<uint32_t, max_alignment>::value> Elf_Word; 46 typedef support::detail::packed_endian_specific_integral< 47 int32_t, target_endianness, 48 MaximumAlignment<int32_t, max_alignment>::value> Elf_Sword; 49 typedef support::detail::packed_endian_specific_integral< 50 uint64_t, target_endianness, 51 MaximumAlignment<uint64_t, max_alignment>::value> Elf_Xword; 52 typedef support::detail::packed_endian_specific_integral< 53 int64_t, target_endianness, 54 MaximumAlignment<int64_t, max_alignment>::value> Elf_Sxword; 55 }; 56 57 template <class ELFT> struct ELFDataTypeTypedefHelper; 58 59 /// ELF 32bit types. 60 template <endianness TargetEndianness, std::size_t MaxAlign> 61 struct ELFDataTypeTypedefHelper<ELFType<TargetEndianness, MaxAlign, false> > 62 : ELFDataTypeTypedefHelperCommon<TargetEndianness, MaxAlign> { 63 typedef uint32_t value_type; 64 typedef support::detail::packed_endian_specific_integral< 65 value_type, TargetEndianness, 66 MaximumAlignment<value_type, MaxAlign>::value> Elf_Addr; 67 typedef support::detail::packed_endian_specific_integral< 68 value_type, TargetEndianness, 69 MaximumAlignment<value_type, MaxAlign>::value> Elf_Off; 70 }; 71 72 /// ELF 64bit types. 73 template <endianness TargetEndianness, std::size_t MaxAlign> 74 struct ELFDataTypeTypedefHelper<ELFType<TargetEndianness, MaxAlign, true> > 75 : ELFDataTypeTypedefHelperCommon<TargetEndianness, MaxAlign> { 76 typedef uint64_t value_type; 77 typedef support::detail::packed_endian_specific_integral< 78 value_type, TargetEndianness, 79 MaximumAlignment<value_type, MaxAlign>::value> Elf_Addr; 80 typedef support::detail::packed_endian_specific_integral< 81 value_type, TargetEndianness, 82 MaximumAlignment<value_type, MaxAlign>::value> Elf_Off; 83 }; 84 85 // I really don't like doing this, but the alternative is copypasta. 86 #define LLVM_ELF_IMPORT_TYPES(E, M, W) \ 87 typedef typename ELFDataTypeTypedefHelper<ELFType<E, M, W> >::Elf_Addr \ 88 Elf_Addr; \ 89 typedef typename ELFDataTypeTypedefHelper<ELFType<E, M, W> >::Elf_Off \ 90 Elf_Off; \ 91 typedef typename ELFDataTypeTypedefHelper<ELFType<E, M, W> >::Elf_Half \ 92 Elf_Half; \ 93 typedef typename ELFDataTypeTypedefHelper<ELFType<E, M, W> >::Elf_Word \ 94 Elf_Word; \ 95 typedef typename ELFDataTypeTypedefHelper<ELFType<E, M, W> >::Elf_Sword \ 96 Elf_Sword; \ 97 typedef typename ELFDataTypeTypedefHelper<ELFType<E, M, W> >::Elf_Xword \ 98 Elf_Xword; \ 99 typedef typename ELFDataTypeTypedefHelper<ELFType<E, M, W> >::Elf_Sxword \ 100 Elf_Sxword; 101 102 #define LLVM_ELF_IMPORT_TYPES_ELFT(ELFT) \ 103 LLVM_ELF_IMPORT_TYPES(ELFT::TargetEndianness, ELFT::MaxAlignment, \ 104 ELFT::Is64Bits) 105 106 // Section header. 107 template <class ELFT> struct Elf_Shdr_Base; 108 109 template <endianness TargetEndianness, std::size_t MaxAlign> 110 struct Elf_Shdr_Base<ELFType<TargetEndianness, MaxAlign, false> > { 111 LLVM_ELF_IMPORT_TYPES(TargetEndianness, MaxAlign, false) 112 Elf_Word sh_name; // Section name (index into string table) 113 Elf_Word sh_type; // Section type (SHT_*) 114 Elf_Word sh_flags; // Section flags (SHF_*) 115 Elf_Addr sh_addr; // Address where section is to be loaded 116 Elf_Off sh_offset; // File offset of section data, in bytes 117 Elf_Word sh_size; // Size of section, in bytes 118 Elf_Word sh_link; // Section type-specific header table index link 119 Elf_Word sh_info; // Section type-specific extra information 120 Elf_Word sh_addralign; // Section address alignment 121 Elf_Word sh_entsize; // Size of records contained within the section 122 }; 123 124 template <endianness TargetEndianness, std::size_t MaxAlign> 125 struct Elf_Shdr_Base<ELFType<TargetEndianness, MaxAlign, true> > { 126 LLVM_ELF_IMPORT_TYPES(TargetEndianness, MaxAlign, true) 127 Elf_Word sh_name; // Section name (index into string table) 128 Elf_Word sh_type; // Section type (SHT_*) 129 Elf_Xword sh_flags; // Section flags (SHF_*) 130 Elf_Addr sh_addr; // Address where section is to be loaded 131 Elf_Off sh_offset; // File offset of section data, in bytes 132 Elf_Xword sh_size; // Size of section, in bytes 133 Elf_Word sh_link; // Section type-specific header table index link 134 Elf_Word sh_info; // Section type-specific extra information 135 Elf_Xword sh_addralign; // Section address alignment 136 Elf_Xword sh_entsize; // Size of records contained within the section 137 }; 138 139 template <class ELFT> 140 struct Elf_Shdr_Impl : Elf_Shdr_Base<ELFT> { 141 using Elf_Shdr_Base<ELFT>::sh_entsize; 142 using Elf_Shdr_Base<ELFT>::sh_size; 143 144 /// @brief Get the number of entities this section contains if it has any. 145 unsigned getEntityCount() const { 146 if (sh_entsize == 0) 147 return 0; 148 return sh_size / sh_entsize; 149 } 150 }; 151 152 template <class ELFT> struct Elf_Sym_Base; 153 154 template <endianness TargetEndianness, std::size_t MaxAlign> 155 struct Elf_Sym_Base<ELFType<TargetEndianness, MaxAlign, false> > { 156 LLVM_ELF_IMPORT_TYPES(TargetEndianness, MaxAlign, false) 157 Elf_Word st_name; // Symbol name (index into string table) 158 Elf_Addr st_value; // Value or address associated with the symbol 159 Elf_Word st_size; // Size of the symbol 160 unsigned char st_info; // Symbol's type and binding attributes 161 unsigned char st_other; // Must be zero; reserved 162 Elf_Half st_shndx; // Which section (header table index) it's defined in 163 }; 164 165 template <endianness TargetEndianness, std::size_t MaxAlign> 166 struct Elf_Sym_Base<ELFType<TargetEndianness, MaxAlign, true> > { 167 LLVM_ELF_IMPORT_TYPES(TargetEndianness, MaxAlign, true) 168 Elf_Word st_name; // Symbol name (index into string table) 169 unsigned char st_info; // Symbol's type and binding attributes 170 unsigned char st_other; // Must be zero; reserved 171 Elf_Half st_shndx; // Which section (header table index) it's defined in 172 Elf_Addr st_value; // Value or address associated with the symbol 173 Elf_Xword st_size; // Size of the symbol 174 }; 175 176 template <class ELFT> 177 struct Elf_Sym_Impl : Elf_Sym_Base<ELFT> { 178 using Elf_Sym_Base<ELFT>::st_info; 179 180 // These accessors and mutators correspond to the ELF32_ST_BIND, 181 // ELF32_ST_TYPE, and ELF32_ST_INFO macros defined in the ELF specification: 182 unsigned char getBinding() const { return st_info >> 4; } 183 unsigned char getType() const { return st_info & 0x0f; } 184 void setBinding(unsigned char b) { setBindingAndType(b, getType()); } 185 void setType(unsigned char t) { setBindingAndType(getBinding(), t); } 186 void setBindingAndType(unsigned char b, unsigned char t) { 187 st_info = (b << 4) + (t & 0x0f); 188 } 189 }; 190 191 /// Elf_Versym: This is the structure of entries in the SHT_GNU_versym section 192 /// (.gnu.version). This structure is identical for ELF32 and ELF64. 193 template <class ELFT> 194 struct Elf_Versym_Impl { 195 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT) 196 Elf_Half vs_index; // Version index with flags (e.g. VERSYM_HIDDEN) 197 }; 198 199 template <class ELFT> struct Elf_Verdaux_Impl; 200 201 /// Elf_Verdef: This is the structure of entries in the SHT_GNU_verdef section 202 /// (.gnu.version_d). This structure is identical for ELF32 and ELF64. 203 template <class ELFT> 204 struct Elf_Verdef_Impl { 205 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT) 206 typedef Elf_Verdaux_Impl<ELFT> Elf_Verdaux; 207 Elf_Half vd_version; // Version of this structure (e.g. VER_DEF_CURRENT) 208 Elf_Half vd_flags; // Bitwise flags (VER_DEF_*) 209 Elf_Half vd_ndx; // Version index, used in .gnu.version entries 210 Elf_Half vd_cnt; // Number of Verdaux entries 211 Elf_Word vd_hash; // Hash of name 212 Elf_Word vd_aux; // Offset to the first Verdaux entry (in bytes) 213 Elf_Word vd_next; // Offset to the next Verdef entry (in bytes) 214 215 /// Get the first Verdaux entry for this Verdef. 216 const Elf_Verdaux *getAux() const { 217 return reinterpret_cast<const Elf_Verdaux *>((const char *)this + vd_aux); 218 } 219 }; 220 221 /// Elf_Verdaux: This is the structure of auxiliary data in the SHT_GNU_verdef 222 /// section (.gnu.version_d). This structure is identical for ELF32 and ELF64. 223 template <class ELFT> 224 struct Elf_Verdaux_Impl { 225 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT) 226 Elf_Word vda_name; // Version name (offset in string table) 227 Elf_Word vda_next; // Offset to next Verdaux entry (in bytes) 228 }; 229 230 /// Elf_Verneed: This is the structure of entries in the SHT_GNU_verneed 231 /// section (.gnu.version_r). This structure is identical for ELF32 and ELF64. 232 template <class ELFT> 233 struct Elf_Verneed_Impl { 234 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT) 235 Elf_Half vn_version; // Version of this structure (e.g. VER_NEED_CURRENT) 236 Elf_Half vn_cnt; // Number of associated Vernaux entries 237 Elf_Word vn_file; // Library name (string table offset) 238 Elf_Word vn_aux; // Offset to first Vernaux entry (in bytes) 239 Elf_Word vn_next; // Offset to next Verneed entry (in bytes) 240 }; 241 242 /// Elf_Vernaux: This is the structure of auxiliary data in SHT_GNU_verneed 243 /// section (.gnu.version_r). This structure is identical for ELF32 and ELF64. 244 template <class ELFT> 245 struct Elf_Vernaux_Impl { 246 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT) 247 Elf_Word vna_hash; // Hash of dependency name 248 Elf_Half vna_flags; // Bitwise Flags (VER_FLAG_*) 249 Elf_Half vna_other; // Version index, used in .gnu.version entries 250 Elf_Word vna_name; // Dependency name 251 Elf_Word vna_next; // Offset to next Vernaux entry (in bytes) 252 }; 253 254 /// Elf_Dyn_Base: This structure matches the form of entries in the dynamic 255 /// table section (.dynamic) look like. 256 template <class ELFT> struct Elf_Dyn_Base; 257 258 template <endianness TargetEndianness, std::size_t MaxAlign> 259 struct Elf_Dyn_Base<ELFType<TargetEndianness, MaxAlign, false> > { 260 LLVM_ELF_IMPORT_TYPES(TargetEndianness, MaxAlign, false) 261 Elf_Sword d_tag; 262 union { 263 Elf_Word d_val; 264 Elf_Addr d_ptr; 265 } d_un; 266 }; 267 268 template <endianness TargetEndianness, std::size_t MaxAlign> 269 struct Elf_Dyn_Base<ELFType<TargetEndianness, MaxAlign, true> > { 270 LLVM_ELF_IMPORT_TYPES(TargetEndianness, MaxAlign, true) 271 Elf_Sxword d_tag; 272 union { 273 Elf_Xword d_val; 274 Elf_Addr d_ptr; 275 } d_un; 276 }; 277 278 /// Elf_Dyn_Impl: This inherits from Elf_Dyn_Base, adding getters and setters. 279 template <class ELFT> 280 struct Elf_Dyn_Impl : Elf_Dyn_Base<ELFT> { 281 using Elf_Dyn_Base<ELFT>::d_tag; 282 using Elf_Dyn_Base<ELFT>::d_un; 283 int64_t getTag() const { return d_tag; } 284 uint64_t getVal() const { return d_un.d_val; } 285 uint64_t getPtr() const { return d_un.ptr; } 286 }; 287 288 // Elf_Rel: Elf Relocation 289 template <class ELFT, bool isRela> struct Elf_Rel_Base; 290 291 template <endianness TargetEndianness, std::size_t MaxAlign> 292 struct Elf_Rel_Base<ELFType<TargetEndianness, MaxAlign, false>, false> { 293 LLVM_ELF_IMPORT_TYPES(TargetEndianness, MaxAlign, false) 294 Elf_Addr r_offset; // Location (file byte offset, or program virtual addr) 295 Elf_Word r_info; // Symbol table index and type of relocation to apply 296 297 uint32_t getRInfo(bool isMips64EL) const { 298 assert(!isMips64EL); 299 return r_info; 300 } 301 void setRInfo(uint32_t R) { r_info = R; } 302 }; 303 304 template <endianness TargetEndianness, std::size_t MaxAlign> 305 struct Elf_Rel_Base<ELFType<TargetEndianness, MaxAlign, true>, false> { 306 LLVM_ELF_IMPORT_TYPES(TargetEndianness, MaxAlign, true) 307 Elf_Addr r_offset; // Location (file byte offset, or program virtual addr) 308 Elf_Xword r_info; // Symbol table index and type of relocation to apply 309 310 uint64_t getRInfo(bool isMips64EL) const { 311 uint64_t t = r_info; 312 if (!isMips64EL) 313 return t; 314 // Mips64 little endian has a "special" encoding of r_info. Instead of one 315 // 64 bit little endian number, it is a little endian 32 bit number followed 316 // by a 32 bit big endian number. 317 return (t << 32) | ((t >> 8) & 0xff000000) | ((t >> 24) & 0x00ff0000) | 318 ((t >> 40) & 0x0000ff00) | ((t >> 56) & 0x000000ff); 319 } 320 void setRInfo(uint64_t R) { 321 // FIXME: Add mips64el support. 322 r_info = R; 323 } 324 }; 325 326 template <endianness TargetEndianness, std::size_t MaxAlign> 327 struct Elf_Rel_Base<ELFType<TargetEndianness, MaxAlign, false>, true> { 328 LLVM_ELF_IMPORT_TYPES(TargetEndianness, MaxAlign, false) 329 Elf_Addr r_offset; // Location (file byte offset, or program virtual addr) 330 Elf_Word r_info; // Symbol table index and type of relocation to apply 331 Elf_Sword r_addend; // Compute value for relocatable field by adding this 332 333 uint32_t getRInfo(bool isMips64EL) const { 334 assert(!isMips64EL); 335 return r_info; 336 } 337 void setRInfo(uint32_t R) { r_info = R; } 338 }; 339 340 template <endianness TargetEndianness, std::size_t MaxAlign> 341 struct Elf_Rel_Base<ELFType<TargetEndianness, MaxAlign, true>, true> { 342 LLVM_ELF_IMPORT_TYPES(TargetEndianness, MaxAlign, true) 343 Elf_Addr r_offset; // Location (file byte offset, or program virtual addr) 344 Elf_Xword r_info; // Symbol table index and type of relocation to apply 345 Elf_Sxword r_addend; // Compute value for relocatable field by adding this. 346 347 uint64_t getRInfo(bool isMips64EL) const { 348 // Mips64 little endian has a "special" encoding of r_info. Instead of one 349 // 64 bit little endian number, it is a little endian 32 bit number followed 350 // by a 32 bit big endian number. 351 uint64_t t = r_info; 352 if (!isMips64EL) 353 return t; 354 return (t << 32) | ((t >> 8) & 0xff000000) | ((t >> 24) & 0x00ff0000) | 355 ((t >> 40) & 0x0000ff00) | ((t >> 56) & 0x000000ff); 356 } 357 void setRInfo(uint64_t R) { 358 // FIXME: Add mips64el support. 359 r_info = R; 360 } 361 }; 362 363 template <class ELFT, bool isRela> struct Elf_Rel_Impl; 364 365 template <endianness TargetEndianness, std::size_t MaxAlign, bool isRela> 366 struct Elf_Rel_Impl<ELFType<TargetEndianness, MaxAlign, true>, 367 isRela> : Elf_Rel_Base< 368 ELFType<TargetEndianness, MaxAlign, true>, isRela> { 369 LLVM_ELF_IMPORT_TYPES(TargetEndianness, MaxAlign, true) 370 371 // These accessors and mutators correspond to the ELF64_R_SYM, ELF64_R_TYPE, 372 // and ELF64_R_INFO macros defined in the ELF specification: 373 uint32_t getSymbol(bool isMips64EL) const { 374 return (uint32_t)(this->getRInfo(isMips64EL) >> 32); 375 } 376 uint32_t getType(bool isMips64EL) const { 377 return (uint32_t)(this->getRInfo(isMips64EL) & 0xffffffffL); 378 } 379 void setSymbol(uint32_t s) { setSymbolAndType(s, getType()); } 380 void setType(uint32_t t) { setSymbolAndType(getSymbol(), t); } 381 void setSymbolAndType(uint32_t s, uint32_t t) { 382 this->setRInfo(((uint64_t)s << 32) + (t & 0xffffffffL)); 383 } 384 }; 385 386 template <endianness TargetEndianness, std::size_t MaxAlign, bool isRela> 387 struct Elf_Rel_Impl<ELFType<TargetEndianness, MaxAlign, false>, 388 isRela> : Elf_Rel_Base< 389 ELFType<TargetEndianness, MaxAlign, false>, isRela> { 390 LLVM_ELF_IMPORT_TYPES(TargetEndianness, MaxAlign, false) 391 392 // These accessors and mutators correspond to the ELF32_R_SYM, ELF32_R_TYPE, 393 // and ELF32_R_INFO macros defined in the ELF specification: 394 uint32_t getSymbol(bool isMips64EL) const { 395 return this->getRInfo(isMips64EL) >> 8; 396 } 397 unsigned char getType(bool isMips64EL) const { 398 return (unsigned char)(this->getRInfo(isMips64EL) & 0x0ff); 399 } 400 void setSymbol(uint32_t s) { setSymbolAndType(s, getType()); } 401 void setType(unsigned char t) { setSymbolAndType(getSymbol(), t); } 402 void setSymbolAndType(uint32_t s, unsigned char t) { 403 this->setRInfo((s << 8) + t); 404 } 405 }; 406 407 template <class ELFT> 408 struct Elf_Ehdr_Impl { 409 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT) 410 unsigned char e_ident[ELF::EI_NIDENT]; // ELF Identification bytes 411 Elf_Half e_type; // Type of file (see ET_*) 412 Elf_Half e_machine; // Required architecture for this file (see EM_*) 413 Elf_Word e_version; // Must be equal to 1 414 Elf_Addr e_entry; // Address to jump to in order to start program 415 Elf_Off e_phoff; // Program header table's file offset, in bytes 416 Elf_Off e_shoff; // Section header table's file offset, in bytes 417 Elf_Word e_flags; // Processor-specific flags 418 Elf_Half e_ehsize; // Size of ELF header, in bytes 419 Elf_Half e_phentsize; // Size of an entry in the program header table 420 Elf_Half e_phnum; // Number of entries in the program header table 421 Elf_Half e_shentsize; // Size of an entry in the section header table 422 Elf_Half e_shnum; // Number of entries in the section header table 423 Elf_Half e_shstrndx; // Section header table index of section name 424 // string table 425 bool checkMagic() const { 426 return (memcmp(e_ident, ELF::ElfMagic, strlen(ELF::ElfMagic))) == 0; 427 } 428 unsigned char getFileClass() const { return e_ident[ELF::EI_CLASS]; } 429 unsigned char getDataEncoding() const { return e_ident[ELF::EI_DATA]; } 430 }; 431 432 template <class ELFT> struct Elf_Phdr_Impl; 433 434 template <endianness TargetEndianness, std::size_t MaxAlign> 435 struct Elf_Phdr_Impl<ELFType<TargetEndianness, MaxAlign, false> > { 436 LLVM_ELF_IMPORT_TYPES(TargetEndianness, MaxAlign, false) 437 Elf_Word p_type; // Type of segment 438 Elf_Off p_offset; // FileOffset where segment is located, in bytes 439 Elf_Addr p_vaddr; // Virtual Address of beginning of segment 440 Elf_Addr p_paddr; // Physical address of beginning of segment (OS-specific) 441 Elf_Word p_filesz; // Num. of bytes in file image of segment (may be zero) 442 Elf_Word p_memsz; // Num. of bytes in mem image of segment (may be zero) 443 Elf_Word p_flags; // Segment flags 444 Elf_Word p_align; // Segment alignment constraint 445 }; 446 447 template <endianness TargetEndianness, std::size_t MaxAlign> 448 struct Elf_Phdr_Impl<ELFType<TargetEndianness, MaxAlign, true> > { 449 LLVM_ELF_IMPORT_TYPES(TargetEndianness, MaxAlign, true) 450 Elf_Word p_type; // Type of segment 451 Elf_Word p_flags; // Segment flags 452 Elf_Off p_offset; // FileOffset where segment is located, in bytes 453 Elf_Addr p_vaddr; // Virtual Address of beginning of segment 454 Elf_Addr p_paddr; // Physical address of beginning of segment (OS-specific) 455 Elf_Xword p_filesz; // Num. of bytes in file image of segment (may be zero) 456 Elf_Xword p_memsz; // Num. of bytes in mem image of segment (may be zero) 457 Elf_Xword p_align; // Segment alignment constraint 458 }; 459 460 } // end namespace object. 461 } // end namespace llvm. 462 463 #endif 464
