1 //===- ELFTypes.h - Endian specific types for ELF ---------------*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef LLVM_OBJECT_ELFTYPES_H 10 #define LLVM_OBJECT_ELFTYPES_H 11 12 #include "llvm/ADT/ArrayRef.h" 13 #include "llvm/ADT/StringRef.h" 14 #include "llvm/BinaryFormat/ELF.h" 15 #include "llvm/Object/Error.h" 16 #include "llvm/Support/Endian.h" 17 #include "llvm/Support/Error.h" 18 #include <cassert> 19 #include <cstdint> 20 #include <cstring> 21 #include <type_traits> 22 23 namespace llvm { 24 namespace object { 25 26 using support::endianness; 27 28 template <class ELFT> struct Elf_Ehdr_Impl; 29 template <class ELFT> struct Elf_Shdr_Impl; 30 template <class ELFT> struct Elf_Sym_Impl; 31 template <class ELFT> struct Elf_Dyn_Impl; 32 template <class ELFT> struct Elf_Phdr_Impl; 33 template <class ELFT, bool isRela> struct Elf_Rel_Impl; 34 template <class ELFT> struct Elf_Verdef_Impl; 35 template <class ELFT> struct Elf_Verdaux_Impl; 36 template <class ELFT> struct Elf_Verneed_Impl; 37 template <class ELFT> struct Elf_Vernaux_Impl; 38 template <class ELFT> struct Elf_Versym_Impl; 39 template <class ELFT> struct Elf_Hash_Impl; 40 template <class ELFT> struct Elf_GnuHash_Impl; 41 template <class ELFT> struct Elf_Chdr_Impl; 42 template <class ELFT> struct Elf_Nhdr_Impl; 43 template <class ELFT> class Elf_Note_Impl; 44 template <class ELFT> class Elf_Note_Iterator_Impl; 45 template <class ELFT> struct Elf_CGProfile_Impl; 46 47 template <endianness E, bool Is64> struct ELFType { 48 private: 49 template <typename Ty> 50 using packed = support::detail::packed_endian_specific_integral<Ty, E, 1>; 51 52 public: 53 static const endianness TargetEndianness = E; 54 static const bool Is64Bits = Is64; 55 56 using uint = typename std::conditional<Is64, uint64_t, uint32_t>::type; 57 using Ehdr = Elf_Ehdr_Impl<ELFType<E, Is64>>; 58 using Shdr = Elf_Shdr_Impl<ELFType<E, Is64>>; 59 using Sym = Elf_Sym_Impl<ELFType<E, Is64>>; 60 using Dyn = Elf_Dyn_Impl<ELFType<E, Is64>>; 61 using Phdr = Elf_Phdr_Impl<ELFType<E, Is64>>; 62 using Rel = Elf_Rel_Impl<ELFType<E, Is64>, false>; 63 using Rela = Elf_Rel_Impl<ELFType<E, Is64>, true>; 64 using Relr = packed<uint>; 65 using Verdef = Elf_Verdef_Impl<ELFType<E, Is64>>; 66 using Verdaux = Elf_Verdaux_Impl<ELFType<E, Is64>>; 67 using Verneed = Elf_Verneed_Impl<ELFType<E, Is64>>; 68 using Vernaux = Elf_Vernaux_Impl<ELFType<E, Is64>>; 69 using Versym = Elf_Versym_Impl<ELFType<E, Is64>>; 70 using Hash = Elf_Hash_Impl<ELFType<E, Is64>>; 71 using GnuHash = Elf_GnuHash_Impl<ELFType<E, Is64>>; 72 using Chdr = Elf_Chdr_Impl<ELFType<E, Is64>>; 73 using Nhdr = Elf_Nhdr_Impl<ELFType<E, Is64>>; 74 using Note = Elf_Note_Impl<ELFType<E, Is64>>; 75 using NoteIterator = Elf_Note_Iterator_Impl<ELFType<E, Is64>>; 76 using CGProfile = Elf_CGProfile_Impl<ELFType<E, Is64>>; 77 using DynRange = ArrayRef<Dyn>; 78 using ShdrRange = ArrayRef<Shdr>; 79 using SymRange = ArrayRef<Sym>; 80 using RelRange = ArrayRef<Rel>; 81 using RelaRange = ArrayRef<Rela>; 82 using RelrRange = ArrayRef<Relr>; 83 using PhdrRange = ArrayRef<Phdr>; 84 85 using Half = packed<uint16_t>; 86 using Word = packed<uint32_t>; 87 using Sword = packed<int32_t>; 88 using Xword = packed<uint64_t>; 89 using Sxword = packed<int64_t>; 90 using Addr = packed<uint>; 91 using Off = packed<uint>; 92 }; 93 94 using ELF32LE = ELFType<support::little, false>; 95 using ELF32BE = ELFType<support::big, false>; 96 using ELF64LE = ELFType<support::little, true>; 97 using ELF64BE = ELFType<support::big, true>; 98 99 // Use an alignment of 2 for the typedefs since that is the worst case for 100 // ELF files in archives. 101 102 // I really don't like doing this, but the alternative is copypasta. 103 #define LLVM_ELF_IMPORT_TYPES_ELFT(ELFT) \ 104 using Elf_Addr = typename ELFT::Addr; \ 105 using Elf_Off = typename ELFT::Off; \ 106 using Elf_Half = typename ELFT::Half; \ 107 using Elf_Word = typename ELFT::Word; \ 108 using Elf_Sword = typename ELFT::Sword; \ 109 using Elf_Xword = typename ELFT::Xword; \ 110 using Elf_Sxword = typename ELFT::Sxword; 111 112 #define LLVM_ELF_COMMA , 113 #define LLVM_ELF_IMPORT_TYPES(E, W) \ 114 LLVM_ELF_IMPORT_TYPES_ELFT(ELFType<E LLVM_ELF_COMMA W>) 115 116 // Section header. 117 template <class ELFT> struct Elf_Shdr_Base; 118 119 template <endianness TargetEndianness> 120 struct Elf_Shdr_Base<ELFType<TargetEndianness, false>> { 121 LLVM_ELF_IMPORT_TYPES(TargetEndianness, false) 122 Elf_Word sh_name; // Section name (index into string table) 123 Elf_Word sh_type; // Section type (SHT_*) 124 Elf_Word sh_flags; // Section flags (SHF_*) 125 Elf_Addr sh_addr; // Address where section is to be loaded 126 Elf_Off sh_offset; // File offset of section data, in bytes 127 Elf_Word sh_size; // Size of section, in bytes 128 Elf_Word sh_link; // Section type-specific header table index link 129 Elf_Word sh_info; // Section type-specific extra information 130 Elf_Word sh_addralign; // Section address alignment 131 Elf_Word sh_entsize; // Size of records contained within the section 132 }; 133 134 template <endianness TargetEndianness> 135 struct Elf_Shdr_Base<ELFType<TargetEndianness, true>> { 136 LLVM_ELF_IMPORT_TYPES(TargetEndianness, true) 137 Elf_Word sh_name; // Section name (index into string table) 138 Elf_Word sh_type; // Section type (SHT_*) 139 Elf_Xword sh_flags; // Section flags (SHF_*) 140 Elf_Addr sh_addr; // Address where section is to be loaded 141 Elf_Off sh_offset; // File offset of section data, in bytes 142 Elf_Xword sh_size; // Size of section, in bytes 143 Elf_Word sh_link; // Section type-specific header table index link 144 Elf_Word sh_info; // Section type-specific extra information 145 Elf_Xword sh_addralign; // Section address alignment 146 Elf_Xword sh_entsize; // Size of records contained within the section 147 }; 148 149 template <class ELFT> 150 struct Elf_Shdr_Impl : Elf_Shdr_Base<ELFT> { 151 using Elf_Shdr_Base<ELFT>::sh_entsize; 152 using Elf_Shdr_Base<ELFT>::sh_size; 153 154 /// Get the number of entities this section contains if it has any. 155 unsigned getEntityCount() const { 156 if (sh_entsize == 0) 157 return 0; 158 return sh_size / sh_entsize; 159 } 160 }; 161 162 template <class ELFT> struct Elf_Sym_Base; 163 164 template <endianness TargetEndianness> 165 struct Elf_Sym_Base<ELFType<TargetEndianness, false>> { 166 LLVM_ELF_IMPORT_TYPES(TargetEndianness, false) 167 Elf_Word st_name; // Symbol name (index into string table) 168 Elf_Addr st_value; // Value or address associated with the symbol 169 Elf_Word st_size; // Size of the symbol 170 unsigned char st_info; // Symbol's type and binding attributes 171 unsigned char st_other; // Must be zero; reserved 172 Elf_Half st_shndx; // Which section (header table index) it's defined in 173 }; 174 175 template <endianness TargetEndianness> 176 struct Elf_Sym_Base<ELFType<TargetEndianness, true>> { 177 LLVM_ELF_IMPORT_TYPES(TargetEndianness, true) 178 Elf_Word st_name; // Symbol name (index into string table) 179 unsigned char st_info; // Symbol's type and binding attributes 180 unsigned char st_other; // Must be zero; reserved 181 Elf_Half st_shndx; // Which section (header table index) it's defined in 182 Elf_Addr st_value; // Value or address associated with the symbol 183 Elf_Xword st_size; // Size of the symbol 184 }; 185 186 template <class ELFT> 187 struct Elf_Sym_Impl : Elf_Sym_Base<ELFT> { 188 using Elf_Sym_Base<ELFT>::st_info; 189 using Elf_Sym_Base<ELFT>::st_shndx; 190 using Elf_Sym_Base<ELFT>::st_other; 191 using Elf_Sym_Base<ELFT>::st_value; 192 193 // These accessors and mutators correspond to the ELF32_ST_BIND, 194 // ELF32_ST_TYPE, and ELF32_ST_INFO macros defined in the ELF specification: 195 unsigned char getBinding() const { return st_info >> 4; } 196 unsigned char getType() const { return st_info & 0x0f; } 197 uint64_t getValue() const { return st_value; } 198 void setBinding(unsigned char b) { setBindingAndType(b, getType()); } 199 void setType(unsigned char t) { setBindingAndType(getBinding(), t); } 200 201 void setBindingAndType(unsigned char b, unsigned char t) { 202 st_info = (b << 4) + (t & 0x0f); 203 } 204 205 /// Access to the STV_xxx flag stored in the first two bits of st_other. 206 /// STV_DEFAULT: 0 207 /// STV_INTERNAL: 1 208 /// STV_HIDDEN: 2 209 /// STV_PROTECTED: 3 210 unsigned char getVisibility() const { return st_other & 0x3; } 211 void setVisibility(unsigned char v) { 212 assert(v < 4 && "Invalid value for visibility"); 213 st_other = (st_other & ~0x3) | v; 214 } 215 216 bool isAbsolute() const { return st_shndx == ELF::SHN_ABS; } 217 218 bool isCommon() const { 219 return getType() == ELF::STT_COMMON || st_shndx == ELF::SHN_COMMON; 220 } 221 222 bool isDefined() const { return !isUndefined(); } 223 224 bool isProcessorSpecific() const { 225 return st_shndx >= ELF::SHN_LOPROC && st_shndx <= ELF::SHN_HIPROC; 226 } 227 228 bool isOSSpecific() const { 229 return st_shndx >= ELF::SHN_LOOS && st_shndx <= ELF::SHN_HIOS; 230 } 231 232 bool isReserved() const { 233 // ELF::SHN_HIRESERVE is 0xffff so st_shndx <= ELF::SHN_HIRESERVE is always 234 // true and some compilers warn about it. 235 return st_shndx >= ELF::SHN_LORESERVE; 236 } 237 238 bool isUndefined() const { return st_shndx == ELF::SHN_UNDEF; } 239 240 bool isExternal() const { 241 return getBinding() != ELF::STB_LOCAL; 242 } 243 244 Expected<StringRef> getName(StringRef StrTab) const; 245 }; 246 247 template <class ELFT> 248 Expected<StringRef> Elf_Sym_Impl<ELFT>::getName(StringRef StrTab) const { 249 uint32_t Offset = this->st_name; 250 if (Offset >= StrTab.size()) 251 return errorCodeToError(object_error::parse_failed); 252 return StringRef(StrTab.data() + Offset); 253 } 254 255 /// Elf_Versym: This is the structure of entries in the SHT_GNU_versym section 256 /// (.gnu.version). This structure is identical for ELF32 and ELF64. 257 template <class ELFT> 258 struct Elf_Versym_Impl { 259 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT) 260 Elf_Half vs_index; // Version index with flags (e.g. VERSYM_HIDDEN) 261 }; 262 263 /// Elf_Verdef: This is the structure of entries in the SHT_GNU_verdef section 264 /// (.gnu.version_d). This structure is identical for ELF32 and ELF64. 265 template <class ELFT> 266 struct Elf_Verdef_Impl { 267 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT) 268 using Elf_Verdaux = Elf_Verdaux_Impl<ELFT>; 269 Elf_Half vd_version; // Version of this structure (e.g. VER_DEF_CURRENT) 270 Elf_Half vd_flags; // Bitwise flags (VER_DEF_*) 271 Elf_Half vd_ndx; // Version index, used in .gnu.version entries 272 Elf_Half vd_cnt; // Number of Verdaux entries 273 Elf_Word vd_hash; // Hash of name 274 Elf_Word vd_aux; // Offset to the first Verdaux entry (in bytes) 275 Elf_Word vd_next; // Offset to the next Verdef entry (in bytes) 276 277 /// Get the first Verdaux entry for this Verdef. 278 const Elf_Verdaux *getAux() const { 279 return reinterpret_cast<const Elf_Verdaux *>((const char *)this + vd_aux); 280 } 281 }; 282 283 /// Elf_Verdaux: This is the structure of auxiliary data in the SHT_GNU_verdef 284 /// section (.gnu.version_d). This structure is identical for ELF32 and ELF64. 285 template <class ELFT> 286 struct Elf_Verdaux_Impl { 287 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT) 288 Elf_Word vda_name; // Version name (offset in string table) 289 Elf_Word vda_next; // Offset to next Verdaux entry (in bytes) 290 }; 291 292 /// Elf_Verneed: This is the structure of entries in the SHT_GNU_verneed 293 /// section (.gnu.version_r). This structure is identical for ELF32 and ELF64. 294 template <class ELFT> 295 struct Elf_Verneed_Impl { 296 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT) 297 Elf_Half vn_version; // Version of this structure (e.g. VER_NEED_CURRENT) 298 Elf_Half vn_cnt; // Number of associated Vernaux entries 299 Elf_Word vn_file; // Library name (string table offset) 300 Elf_Word vn_aux; // Offset to first Vernaux entry (in bytes) 301 Elf_Word vn_next; // Offset to next Verneed entry (in bytes) 302 }; 303 304 /// Elf_Vernaux: This is the structure of auxiliary data in SHT_GNU_verneed 305 /// section (.gnu.version_r). This structure is identical for ELF32 and ELF64. 306 template <class ELFT> 307 struct Elf_Vernaux_Impl { 308 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT) 309 Elf_Word vna_hash; // Hash of dependency name 310 Elf_Half vna_flags; // Bitwise Flags (VER_FLAG_*) 311 Elf_Half vna_other; // Version index, used in .gnu.version entries 312 Elf_Word vna_name; // Dependency name 313 Elf_Word vna_next; // Offset to next Vernaux entry (in bytes) 314 }; 315 316 /// Elf_Dyn_Base: This structure matches the form of entries in the dynamic 317 /// table section (.dynamic) look like. 318 template <class ELFT> struct Elf_Dyn_Base; 319 320 template <endianness TargetEndianness> 321 struct Elf_Dyn_Base<ELFType<TargetEndianness, false>> { 322 LLVM_ELF_IMPORT_TYPES(TargetEndianness, false) 323 Elf_Sword d_tag; 324 union { 325 Elf_Word d_val; 326 Elf_Addr d_ptr; 327 } d_un; 328 }; 329 330 template <endianness TargetEndianness> 331 struct Elf_Dyn_Base<ELFType<TargetEndianness, true>> { 332 LLVM_ELF_IMPORT_TYPES(TargetEndianness, true) 333 Elf_Sxword d_tag; 334 union { 335 Elf_Xword d_val; 336 Elf_Addr d_ptr; 337 } d_un; 338 }; 339 340 /// Elf_Dyn_Impl: This inherits from Elf_Dyn_Base, adding getters. 341 template <class ELFT> 342 struct Elf_Dyn_Impl : Elf_Dyn_Base<ELFT> { 343 using Elf_Dyn_Base<ELFT>::d_tag; 344 using Elf_Dyn_Base<ELFT>::d_un; 345 using intX_t = typename std::conditional<ELFT::Is64Bits, 346 int64_t, int32_t>::type; 347 using uintX_t = typename std::conditional<ELFT::Is64Bits, 348 uint64_t, uint32_t>::type; 349 intX_t getTag() const { return d_tag; } 350 uintX_t getVal() const { return d_un.d_val; } 351 uintX_t getPtr() const { return d_un.d_ptr; } 352 }; 353 354 template <endianness TargetEndianness> 355 struct Elf_Rel_Impl<ELFType<TargetEndianness, false>, false> { 356 LLVM_ELF_IMPORT_TYPES(TargetEndianness, false) 357 static const bool IsRela = false; 358 Elf_Addr r_offset; // Location (file byte offset, or program virtual addr) 359 Elf_Word r_info; // Symbol table index and type of relocation to apply 360 361 uint32_t getRInfo(bool isMips64EL) const { 362 assert(!isMips64EL); 363 return r_info; 364 } 365 void setRInfo(uint32_t R, bool IsMips64EL) { 366 assert(!IsMips64EL); 367 r_info = R; 368 } 369 370 // These accessors and mutators correspond to the ELF32_R_SYM, ELF32_R_TYPE, 371 // and ELF32_R_INFO macros defined in the ELF specification: 372 uint32_t getSymbol(bool isMips64EL) const { 373 return this->getRInfo(isMips64EL) >> 8; 374 } 375 unsigned char getType(bool isMips64EL) const { 376 return (unsigned char)(this->getRInfo(isMips64EL) & 0x0ff); 377 } 378 void setSymbol(uint32_t s, bool IsMips64EL) { 379 setSymbolAndType(s, getType(IsMips64EL), IsMips64EL); 380 } 381 void setType(unsigned char t, bool IsMips64EL) { 382 setSymbolAndType(getSymbol(IsMips64EL), t, IsMips64EL); 383 } 384 void setSymbolAndType(uint32_t s, unsigned char t, bool IsMips64EL) { 385 this->setRInfo((s << 8) + t, IsMips64EL); 386 } 387 }; 388 389 template <endianness TargetEndianness> 390 struct Elf_Rel_Impl<ELFType<TargetEndianness, false>, true> 391 : public Elf_Rel_Impl<ELFType<TargetEndianness, false>, false> { 392 LLVM_ELF_IMPORT_TYPES(TargetEndianness, false) 393 static const bool IsRela = true; 394 Elf_Sword r_addend; // Compute value for relocatable field by adding this 395 }; 396 397 template <endianness TargetEndianness> 398 struct Elf_Rel_Impl<ELFType<TargetEndianness, true>, false> { 399 LLVM_ELF_IMPORT_TYPES(TargetEndianness, true) 400 static const bool IsRela = false; 401 Elf_Addr r_offset; // Location (file byte offset, or program virtual addr) 402 Elf_Xword r_info; // Symbol table index and type of relocation to apply 403 404 uint64_t getRInfo(bool isMips64EL) const { 405 uint64_t t = r_info; 406 if (!isMips64EL) 407 return t; 408 // Mips64 little endian has a "special" encoding of r_info. Instead of one 409 // 64 bit little endian number, it is a little endian 32 bit number followed 410 // by a 32 bit big endian number. 411 return (t << 32) | ((t >> 8) & 0xff000000) | ((t >> 24) & 0x00ff0000) | 412 ((t >> 40) & 0x0000ff00) | ((t >> 56) & 0x000000ff); 413 } 414 415 void setRInfo(uint64_t R, bool IsMips64EL) { 416 if (IsMips64EL) 417 r_info = (R >> 32) | ((R & 0xff000000) << 8) | ((R & 0x00ff0000) << 24) | 418 ((R & 0x0000ff00) << 40) | ((R & 0x000000ff) << 56); 419 else 420 r_info = R; 421 } 422 423 // These accessors and mutators correspond to the ELF64_R_SYM, ELF64_R_TYPE, 424 // and ELF64_R_INFO macros defined in the ELF specification: 425 uint32_t getSymbol(bool isMips64EL) const { 426 return (uint32_t)(this->getRInfo(isMips64EL) >> 32); 427 } 428 uint32_t getType(bool isMips64EL) const { 429 return (uint32_t)(this->getRInfo(isMips64EL) & 0xffffffffL); 430 } 431 void setSymbol(uint32_t s, bool IsMips64EL) { 432 setSymbolAndType(s, getType(IsMips64EL), IsMips64EL); 433 } 434 void setType(uint32_t t, bool IsMips64EL) { 435 setSymbolAndType(getSymbol(IsMips64EL), t, IsMips64EL); 436 } 437 void setSymbolAndType(uint32_t s, uint32_t t, bool IsMips64EL) { 438 this->setRInfo(((uint64_t)s << 32) + (t & 0xffffffffL), IsMips64EL); 439 } 440 }; 441 442 template <endianness TargetEndianness> 443 struct Elf_Rel_Impl<ELFType<TargetEndianness, true>, true> 444 : public Elf_Rel_Impl<ELFType<TargetEndianness, true>, false> { 445 LLVM_ELF_IMPORT_TYPES(TargetEndianness, true) 446 static const bool IsRela = true; 447 Elf_Sxword r_addend; // Compute value for relocatable field by adding this. 448 }; 449 450 template <class ELFT> 451 struct Elf_Ehdr_Impl { 452 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT) 453 unsigned char e_ident[ELF::EI_NIDENT]; // ELF Identification bytes 454 Elf_Half e_type; // Type of file (see ET_*) 455 Elf_Half e_machine; // Required architecture for this file (see EM_*) 456 Elf_Word e_version; // Must be equal to 1 457 Elf_Addr e_entry; // Address to jump to in order to start program 458 Elf_Off e_phoff; // Program header table's file offset, in bytes 459 Elf_Off e_shoff; // Section header table's file offset, in bytes 460 Elf_Word e_flags; // Processor-specific flags 461 Elf_Half e_ehsize; // Size of ELF header, in bytes 462 Elf_Half e_phentsize; // Size of an entry in the program header table 463 Elf_Half e_phnum; // Number of entries in the program header table 464 Elf_Half e_shentsize; // Size of an entry in the section header table 465 Elf_Half e_shnum; // Number of entries in the section header table 466 Elf_Half e_shstrndx; // Section header table index of section name 467 // string table 468 469 bool checkMagic() const { 470 return (memcmp(e_ident, ELF::ElfMagic, strlen(ELF::ElfMagic))) == 0; 471 } 472 473 unsigned char getFileClass() const { return e_ident[ELF::EI_CLASS]; } 474 unsigned char getDataEncoding() const { return e_ident[ELF::EI_DATA]; } 475 }; 476 477 template <endianness TargetEndianness> 478 struct Elf_Phdr_Impl<ELFType<TargetEndianness, false>> { 479 LLVM_ELF_IMPORT_TYPES(TargetEndianness, false) 480 Elf_Word p_type; // Type of segment 481 Elf_Off p_offset; // FileOffset where segment is located, in bytes 482 Elf_Addr p_vaddr; // Virtual Address of beginning of segment 483 Elf_Addr p_paddr; // Physical address of beginning of segment (OS-specific) 484 Elf_Word p_filesz; // Num. of bytes in file image of segment (may be zero) 485 Elf_Word p_memsz; // Num. of bytes in mem image of segment (may be zero) 486 Elf_Word p_flags; // Segment flags 487 Elf_Word p_align; // Segment alignment constraint 488 }; 489 490 template <endianness TargetEndianness> 491 struct Elf_Phdr_Impl<ELFType<TargetEndianness, true>> { 492 LLVM_ELF_IMPORT_TYPES(TargetEndianness, true) 493 Elf_Word p_type; // Type of segment 494 Elf_Word p_flags; // Segment flags 495 Elf_Off p_offset; // FileOffset where segment is located, in bytes 496 Elf_Addr p_vaddr; // Virtual Address of beginning of segment 497 Elf_Addr p_paddr; // Physical address of beginning of segment (OS-specific) 498 Elf_Xword p_filesz; // Num. of bytes in file image of segment (may be zero) 499 Elf_Xword p_memsz; // Num. of bytes in mem image of segment (may be zero) 500 Elf_Xword p_align; // Segment alignment constraint 501 }; 502 503 // ELFT needed for endianness. 504 template <class ELFT> 505 struct Elf_Hash_Impl { 506 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT) 507 Elf_Word nbucket; 508 Elf_Word nchain; 509 510 ArrayRef<Elf_Word> buckets() const { 511 return ArrayRef<Elf_Word>(&nbucket + 2, &nbucket + 2 + nbucket); 512 } 513 514 ArrayRef<Elf_Word> chains() const { 515 return ArrayRef<Elf_Word>(&nbucket + 2 + nbucket, 516 &nbucket + 2 + nbucket + nchain); 517 } 518 }; 519 520 // .gnu.hash section 521 template <class ELFT> 522 struct Elf_GnuHash_Impl { 523 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT) 524 Elf_Word nbuckets; 525 Elf_Word symndx; 526 Elf_Word maskwords; 527 Elf_Word shift2; 528 529 ArrayRef<Elf_Off> filter() const { 530 return ArrayRef<Elf_Off>(reinterpret_cast<const Elf_Off *>(&shift2 + 1), 531 maskwords); 532 } 533 534 ArrayRef<Elf_Word> buckets() const { 535 return ArrayRef<Elf_Word>( 536 reinterpret_cast<const Elf_Word *>(filter().end()), nbuckets); 537 } 538 539 ArrayRef<Elf_Word> values(unsigned DynamicSymCount) const { 540 return ArrayRef<Elf_Word>(buckets().end(), DynamicSymCount - symndx); 541 } 542 }; 543 544 // Compressed section headers. 545 // http://www.sco.com/developers/gabi/latest/ch4.sheader.html#compression_header 546 template <endianness TargetEndianness> 547 struct Elf_Chdr_Impl<ELFType<TargetEndianness, false>> { 548 LLVM_ELF_IMPORT_TYPES(TargetEndianness, false) 549 Elf_Word ch_type; 550 Elf_Word ch_size; 551 Elf_Word ch_addralign; 552 }; 553 554 template <endianness TargetEndianness> 555 struct Elf_Chdr_Impl<ELFType<TargetEndianness, true>> { 556 LLVM_ELF_IMPORT_TYPES(TargetEndianness, true) 557 Elf_Word ch_type; 558 Elf_Word ch_reserved; 559 Elf_Xword ch_size; 560 Elf_Xword ch_addralign; 561 }; 562 563 /// Note header 564 template <class ELFT> 565 struct Elf_Nhdr_Impl { 566 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT) 567 Elf_Word n_namesz; 568 Elf_Word n_descsz; 569 Elf_Word n_type; 570 571 /// The alignment of the name and descriptor. 572 /// 573 /// Implementations differ from the specification here: in practice all 574 /// variants align both the name and descriptor to 4-bytes. 575 static const unsigned int Align = 4; 576 577 /// Get the size of the note, including name, descriptor, and padding. 578 size_t getSize() const { 579 return sizeof(*this) + alignTo<Align>(n_namesz) + alignTo<Align>(n_descsz); 580 } 581 }; 582 583 /// An ELF note. 584 /// 585 /// Wraps a note header, providing methods for accessing the name and 586 /// descriptor safely. 587 template <class ELFT> 588 class Elf_Note_Impl { 589 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT) 590 591 const Elf_Nhdr_Impl<ELFT> &Nhdr; 592 593 template <class NoteIteratorELFT> friend class Elf_Note_Iterator_Impl; 594 595 public: 596 Elf_Note_Impl(const Elf_Nhdr_Impl<ELFT> &Nhdr) : Nhdr(Nhdr) {} 597 598 /// Get the note's name, excluding the terminating null byte. 599 StringRef getName() const { 600 if (!Nhdr.n_namesz) 601 return StringRef(); 602 return StringRef(reinterpret_cast<const char *>(&Nhdr) + sizeof(Nhdr), 603 Nhdr.n_namesz - 1); 604 } 605 606 /// Get the note's descriptor. 607 ArrayRef<uint8_t> getDesc() const { 608 if (!Nhdr.n_descsz) 609 return ArrayRef<uint8_t>(); 610 return ArrayRef<uint8_t>( 611 reinterpret_cast<const uint8_t *>(&Nhdr) + sizeof(Nhdr) + 612 alignTo<Elf_Nhdr_Impl<ELFT>::Align>(Nhdr.n_namesz), 613 Nhdr.n_descsz); 614 } 615 616 /// Get the note's type. 617 Elf_Word getType() const { return Nhdr.n_type; } 618 }; 619 620 template <class ELFT> 621 class Elf_Note_Iterator_Impl 622 : std::iterator<std::forward_iterator_tag, Elf_Note_Impl<ELFT>> { 623 // Nhdr being a nullptr marks the end of iteration. 624 const Elf_Nhdr_Impl<ELFT> *Nhdr = nullptr; 625 size_t RemainingSize = 0u; 626 Error *Err = nullptr; 627 628 template <class ELFFileELFT> friend class ELFFile; 629 630 // Stop iteration and indicate an overflow. 631 void stopWithOverflowError() { 632 Nhdr = nullptr; 633 *Err = make_error<StringError>("ELF note overflows container", 634 object_error::parse_failed); 635 } 636 637 // Advance Nhdr by NoteSize bytes, starting from NhdrPos. 638 // 639 // Assumes NoteSize <= RemainingSize. Ensures Nhdr->getSize() <= RemainingSize 640 // upon returning. Handles stopping iteration when reaching the end of the 641 // container, either cleanly or with an overflow error. 642 void advanceNhdr(const uint8_t *NhdrPos, size_t NoteSize) { 643 RemainingSize -= NoteSize; 644 if (RemainingSize == 0u) { 645 // Ensure that if the iterator walks to the end, the error is checked 646 // afterwards. 647 *Err = Error::success(); 648 Nhdr = nullptr; 649 } else if (sizeof(*Nhdr) > RemainingSize) 650 stopWithOverflowError(); 651 else { 652 Nhdr = reinterpret_cast<const Elf_Nhdr_Impl<ELFT> *>(NhdrPos + NoteSize); 653 if (Nhdr->getSize() > RemainingSize) 654 stopWithOverflowError(); 655 else 656 *Err = Error::success(); 657 } 658 } 659 660 Elf_Note_Iterator_Impl() {} 661 explicit Elf_Note_Iterator_Impl(Error &Err) : Err(&Err) {} 662 Elf_Note_Iterator_Impl(const uint8_t *Start, size_t Size, Error &Err) 663 : RemainingSize(Size), Err(&Err) { 664 consumeError(std::move(Err)); 665 assert(Start && "ELF note iterator starting at NULL"); 666 advanceNhdr(Start, 0u); 667 } 668 669 public: 670 Elf_Note_Iterator_Impl &operator++() { 671 assert(Nhdr && "incremented ELF note end iterator"); 672 const uint8_t *NhdrPos = reinterpret_cast<const uint8_t *>(Nhdr); 673 size_t NoteSize = Nhdr->getSize(); 674 advanceNhdr(NhdrPos, NoteSize); 675 return *this; 676 } 677 bool operator==(Elf_Note_Iterator_Impl Other) const { 678 if (!Nhdr && Other.Err) 679 (void)(bool)(*Other.Err); 680 if (!Other.Nhdr && Err) 681 (void)(bool)(*Err); 682 return Nhdr == Other.Nhdr; 683 } 684 bool operator!=(Elf_Note_Iterator_Impl Other) const { 685 return !(*this == Other); 686 } 687 Elf_Note_Impl<ELFT> operator*() const { 688 assert(Nhdr && "dereferenced ELF note end iterator"); 689 return Elf_Note_Impl<ELFT>(*Nhdr); 690 } 691 }; 692 693 template <class ELFT> struct Elf_CGProfile_Impl { 694 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT) 695 Elf_Word cgp_from; 696 Elf_Word cgp_to; 697 Elf_Xword cgp_weight; 698 }; 699 700 // MIPS .reginfo section 701 template <class ELFT> 702 struct Elf_Mips_RegInfo; 703 704 template <support::endianness TargetEndianness> 705 struct Elf_Mips_RegInfo<ELFType<TargetEndianness, false>> { 706 LLVM_ELF_IMPORT_TYPES(TargetEndianness, false) 707 Elf_Word ri_gprmask; // bit-mask of used general registers 708 Elf_Word ri_cprmask[4]; // bit-mask of used co-processor registers 709 Elf_Addr ri_gp_value; // gp register value 710 }; 711 712 template <support::endianness TargetEndianness> 713 struct Elf_Mips_RegInfo<ELFType<TargetEndianness, true>> { 714 LLVM_ELF_IMPORT_TYPES(TargetEndianness, true) 715 Elf_Word ri_gprmask; // bit-mask of used general registers 716 Elf_Word ri_pad; // unused padding field 717 Elf_Word ri_cprmask[4]; // bit-mask of used co-processor registers 718 Elf_Addr ri_gp_value; // gp register value 719 }; 720 721 // .MIPS.options section 722 template <class ELFT> struct Elf_Mips_Options { 723 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT) 724 uint8_t kind; // Determines interpretation of variable part of descriptor 725 uint8_t size; // Byte size of descriptor, including this header 726 Elf_Half section; // Section header index of section affected, 727 // or 0 for global options 728 Elf_Word info; // Kind-specific information 729 730 Elf_Mips_RegInfo<ELFT> &getRegInfo() { 731 assert(kind == ELF::ODK_REGINFO); 732 return *reinterpret_cast<Elf_Mips_RegInfo<ELFT> *>( 733 (uint8_t *)this + sizeof(Elf_Mips_Options)); 734 } 735 const Elf_Mips_RegInfo<ELFT> &getRegInfo() const { 736 return const_cast<Elf_Mips_Options *>(this)->getRegInfo(); 737 } 738 }; 739 740 // .MIPS.abiflags section content 741 template <class ELFT> struct Elf_Mips_ABIFlags { 742 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT) 743 Elf_Half version; // Version of the structure 744 uint8_t isa_level; // ISA level: 1-5, 32, and 64 745 uint8_t isa_rev; // ISA revision (0 for MIPS I - MIPS V) 746 uint8_t gpr_size; // General purpose registers size 747 uint8_t cpr1_size; // Co-processor 1 registers size 748 uint8_t cpr2_size; // Co-processor 2 registers size 749 uint8_t fp_abi; // Floating-point ABI flag 750 Elf_Word isa_ext; // Processor-specific extension 751 Elf_Word ases; // ASEs flags 752 Elf_Word flags1; // General flags 753 Elf_Word flags2; // General flags 754 }; 755 756 } // end namespace object. 757 } // end namespace llvm. 758 759 #endif // LLVM_OBJECT_ELFTYPES_H 760