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 "llvm/Support/MathExtras.h"
19#include <cassert>
20#include <cstdint>
21#include <cstring>
22#include <type_traits>
23
24namespace llvm {
25namespace object {
26
27using support::endianness;
28
29template <class ELFT> struct Elf_Ehdr_Impl;
30template <class ELFT> struct Elf_Shdr_Impl;
31template <class ELFT> struct Elf_Sym_Impl;
32template <class ELFT> struct Elf_Dyn_Impl;
33template <class ELFT> struct Elf_Phdr_Impl;
34template <class ELFT, bool isRela> struct Elf_Rel_Impl;
35template <class ELFT> struct Elf_Verdef_Impl;
36template <class ELFT> struct Elf_Verdaux_Impl;
37template <class ELFT> struct Elf_Verneed_Impl;
38template <class ELFT> struct Elf_Vernaux_Impl;
39template <class ELFT> struct Elf_Versym_Impl;
40template <class ELFT> struct Elf_Hash_Impl;
41template <class ELFT> struct Elf_GnuHash_Impl;
42template <class ELFT> struct Elf_Chdr_Impl;
43template <class ELFT> struct Elf_Nhdr_Impl;
44template <class ELFT> class Elf_Note_Impl;
45template <class ELFT> class Elf_Note_Iterator_Impl;
46template <class ELFT> struct Elf_CGProfile_Impl;
47
48template <endianness E, bool Is64> struct ELFType {
49private:
50 template <typename Ty>
51 using packed = support::detail::packed_endian_specific_integral<Ty, E, 1>;
52
53public:
54 static const endianness TargetEndianness = E;
55 static const bool Is64Bits = Is64;
56
57 using uint = std::conditional_t<Is64, uint64_t, uint32_t>;
58 using Ehdr = Elf_Ehdr_Impl<ELFType<E, Is64>>;
59 using Shdr = Elf_Shdr_Impl<ELFType<E, Is64>>;
60 using Sym = Elf_Sym_Impl<ELFType<E, Is64>>;
61 using Dyn = Elf_Dyn_Impl<ELFType<E, Is64>>;
62 using Phdr = Elf_Phdr_Impl<ELFType<E, Is64>>;
63 using Rel = Elf_Rel_Impl<ELFType<E, Is64>, false>;
64 using Rela = Elf_Rel_Impl<ELFType<E, Is64>, true>;
65 using Relr = packed<uint>;
66 using Verdef = Elf_Verdef_Impl<ELFType<E, Is64>>;
67 using Verdaux = Elf_Verdaux_Impl<ELFType<E, Is64>>;
68 using Verneed = Elf_Verneed_Impl<ELFType<E, Is64>>;
69 using Vernaux = Elf_Vernaux_Impl<ELFType<E, Is64>>;
70 using Versym = Elf_Versym_Impl<ELFType<E, Is64>>;
71 using Hash = Elf_Hash_Impl<ELFType<E, Is64>>;
72 using GnuHash = Elf_GnuHash_Impl<ELFType<E, Is64>>;
73 using Chdr = Elf_Chdr_Impl<ELFType<E, Is64>>;
74 using Nhdr = Elf_Nhdr_Impl<ELFType<E, Is64>>;
75 using Note = Elf_Note_Impl<ELFType<E, Is64>>;
76 using NoteIterator = Elf_Note_Iterator_Impl<ELFType<E, Is64>>;
77 using CGProfile = Elf_CGProfile_Impl<ELFType<E, Is64>>;
78 using DynRange = ArrayRef<Dyn>;
79 using ShdrRange = ArrayRef<Shdr>;
80 using SymRange = ArrayRef<Sym>;
81 using RelRange = ArrayRef<Rel>;
82 using RelaRange = ArrayRef<Rela>;
83 using RelrRange = ArrayRef<Relr>;
84 using PhdrRange = ArrayRef<Phdr>;
85
86 using Half = packed<uint16_t>;
87 using Word = packed<uint32_t>;
88 using Sword = packed<int32_t>;
89 using Xword = packed<uint64_t>;
90 using Sxword = packed<int64_t>;
91 using Addr = packed<uint>;
92 using Off = packed<uint>;
93};
94
95using ELF32LE = ELFType<support::little, false>;
96using ELF32BE = ELFType<support::big, false>;
97using ELF64LE = ELFType<support::little, true>;
98using ELF64BE = ELFType<support::big, true>;
99
100// Use an alignment of 2 for the typedefs since that is the worst case for
101// ELF files in archives.
102
103// I really don't like doing this, but the alternative is copypasta.
104#define LLVM_ELF_IMPORT_TYPES_ELFT(ELFT) \
105 using Elf_Addr = typename ELFT::Addr; \
106 using Elf_Off = typename ELFT::Off; \
107 using Elf_Half = typename ELFT::Half; \
108 using Elf_Word = typename ELFT::Word; \
109 using Elf_Sword = typename ELFT::Sword; \
110 using Elf_Xword = typename ELFT::Xword; \
111 using Elf_Sxword = typename ELFT::Sxword; \
112 using uintX_t = typename ELFT::uint; \
113 using Elf_Ehdr = typename ELFT::Ehdr; \
114 using Elf_Shdr = typename ELFT::Shdr; \
115 using Elf_Sym = typename ELFT::Sym; \
116 using Elf_Dyn = typename ELFT::Dyn; \
117 using Elf_Phdr = typename ELFT::Phdr; \
118 using Elf_Rel = typename ELFT::Rel; \
119 using Elf_Rela = typename ELFT::Rela; \
120 using Elf_Relr = typename ELFT::Relr; \
121 using Elf_Verdef = typename ELFT::Verdef; \
122 using Elf_Verdaux = typename ELFT::Verdaux; \
123 using Elf_Verneed = typename ELFT::Verneed; \
124 using Elf_Vernaux = typename ELFT::Vernaux; \
125 using Elf_Versym = typename ELFT::Versym; \
126 using Elf_Hash = typename ELFT::Hash; \
127 using Elf_GnuHash = typename ELFT::GnuHash; \
128 using Elf_Nhdr = typename ELFT::Nhdr; \
129 using Elf_Note = typename ELFT::Note; \
130 using Elf_Note_Iterator = typename ELFT::NoteIterator; \
131 using Elf_CGProfile = typename ELFT::CGProfile; \
132 using Elf_Dyn_Range = typename ELFT::DynRange; \
133 using Elf_Shdr_Range = typename ELFT::ShdrRange; \
134 using Elf_Sym_Range = typename ELFT::SymRange; \
135 using Elf_Rel_Range = typename ELFT::RelRange; \
136 using Elf_Rela_Range = typename ELFT::RelaRange; \
137 using Elf_Relr_Range = typename ELFT::RelrRange; \
138 using Elf_Phdr_Range = typename ELFT::PhdrRange;
139
140#define LLVM_ELF_COMMA ,
141#define LLVM_ELF_IMPORT_TYPES(E, W) \
142 LLVM_ELF_IMPORT_TYPES_ELFT(ELFType<E LLVM_ELF_COMMA W>)
143
144// Section header.
145template <class ELFT> struct Elf_Shdr_Base;
146
147template <endianness TargetEndianness>
148struct Elf_Shdr_Base<ELFType<TargetEndianness, false>> {
149 LLVM_ELF_IMPORT_TYPES(TargetEndianness, false)
150 Elf_Word sh_name; // Section name (index into string table)
151 Elf_Word sh_type; // Section type (SHT_*)
152 Elf_Word sh_flags; // Section flags (SHF_*)
153 Elf_Addr sh_addr; // Address where section is to be loaded
154 Elf_Off sh_offset; // File offset of section data, in bytes
155 Elf_Word sh_size; // Size of section, in bytes
156 Elf_Word sh_link; // Section type-specific header table index link
157 Elf_Word sh_info; // Section type-specific extra information
158 Elf_Word sh_addralign; // Section address alignment
159 Elf_Word sh_entsize; // Size of records contained within the section
160};
161
162template <endianness TargetEndianness>
163struct Elf_Shdr_Base<ELFType<TargetEndianness, true>> {
164 LLVM_ELF_IMPORT_TYPES(TargetEndianness, true)
165 Elf_Word sh_name; // Section name (index into string table)
166 Elf_Word sh_type; // Section type (SHT_*)
167 Elf_Xword sh_flags; // Section flags (SHF_*)
168 Elf_Addr sh_addr; // Address where section is to be loaded
169 Elf_Off sh_offset; // File offset of section data, in bytes
170 Elf_Xword sh_size; // Size of section, in bytes
171 Elf_Word sh_link; // Section type-specific header table index link
172 Elf_Word sh_info; // Section type-specific extra information
173 Elf_Xword sh_addralign; // Section address alignment
174 Elf_Xword sh_entsize; // Size of records contained within the section
175};
176
177template <class ELFT>
178struct Elf_Shdr_Impl : Elf_Shdr_Base<ELFT> {
179 using Elf_Shdr_Base<ELFT>::sh_entsize;
180 using Elf_Shdr_Base<ELFT>::sh_size;
181
182 /// Get the number of entities this section contains if it has any.
183 unsigned getEntityCount() const {
184 if (sh_entsize == 0)
185 return 0;
186 return sh_size / sh_entsize;
187 }
188};
189
190template <class ELFT> struct Elf_Sym_Base;
191
192template <endianness TargetEndianness>
193struct Elf_Sym_Base<ELFType<TargetEndianness, false>> {
194 LLVM_ELF_IMPORT_TYPES(TargetEndianness, false)
195 Elf_Word st_name; // Symbol name (index into string table)
196 Elf_Addr st_value; // Value or address associated with the symbol
197 Elf_Word st_size; // Size of the symbol
198 unsigned char st_info; // Symbol's type and binding attributes
199 unsigned char st_other; // Must be zero; reserved
200 Elf_Half st_shndx; // Which section (header table index) it's defined in
201};
202
203template <endianness TargetEndianness>
204struct Elf_Sym_Base<ELFType<TargetEndianness, true>> {
205 LLVM_ELF_IMPORT_TYPES(TargetEndianness, true)
206 Elf_Word st_name; // Symbol name (index into string table)
207 unsigned char st_info; // Symbol's type and binding attributes
208 unsigned char st_other; // Must be zero; reserved
209 Elf_Half st_shndx; // Which section (header table index) it's defined in
210 Elf_Addr st_value; // Value or address associated with the symbol
211 Elf_Xword st_size; // Size of the symbol
212};
213
214template <class ELFT>
215struct Elf_Sym_Impl : Elf_Sym_Base<ELFT> {
216 using Elf_Sym_Base<ELFT>::st_info;
217 using Elf_Sym_Base<ELFT>::st_shndx;
218 using Elf_Sym_Base<ELFT>::st_other;
219 using Elf_Sym_Base<ELFT>::st_value;
220
221 // These accessors and mutators correspond to the ELF32_ST_BIND,
222 // ELF32_ST_TYPE, and ELF32_ST_INFO macros defined in the ELF specification:
223 unsigned char getBinding() const { return st_info >> 4; }
224 unsigned char getType() const { return st_info & 0x0f; }
225 uint64_t getValue() const { return st_value; }
226 void setBinding(unsigned char b) { setBindingAndType(b, getType()); }
227 void setType(unsigned char t) { setBindingAndType(getBinding(), t); }
228
229 void setBindingAndType(unsigned char b, unsigned char t) {
230 st_info = (b << 4) + (t & 0x0f);
231 }
232
233 /// Access to the STV_xxx flag stored in the first two bits of st_other.
234 /// STV_DEFAULT: 0
235 /// STV_INTERNAL: 1
236 /// STV_HIDDEN: 2
237 /// STV_PROTECTED: 3
238 unsigned char getVisibility() const { return st_other & 0x3; }
239 void setVisibility(unsigned char v) {
240 assert(v < 4 && "Invalid value for visibility");
241 st_other = (st_other & ~0x3) | v;
242 }
243
244 bool isAbsolute() const { return st_shndx == ELF::SHN_ABS; }
245
246 bool isCommon() const {
247 return getType() == ELF::STT_COMMON || st_shndx == ELF::SHN_COMMON;
248 }
249
250 bool isDefined() const { return !isUndefined(); }
251
252 bool isProcessorSpecific() const {
253 return st_shndx >= ELF::SHN_LOPROC && st_shndx <= ELF::SHN_HIPROC;
254 }
255
256 bool isOSSpecific() const {
257 return st_shndx >= ELF::SHN_LOOS && st_shndx <= ELF::SHN_HIOS;
258 }
259
260 bool isReserved() const {
261 // ELF::SHN_HIRESERVE is 0xffff so st_shndx <= ELF::SHN_HIRESERVE is always
262 // true and some compilers warn about it.
263 return st_shndx >= ELF::SHN_LORESERVE;
264 }
265
266 bool isUndefined() const { return st_shndx == ELF::SHN_UNDEF; }
267
268 bool isExternal() const {
269 return getBinding() != ELF::STB_LOCAL;
270 }
271
272 Expected<StringRef> getName(StringRef StrTab) const;
273};
274
275template <class ELFT>
276Expected<StringRef> Elf_Sym_Impl<ELFT>::getName(StringRef StrTab) const {
277 uint32_t Offset = this->st_name;
278 if (Offset >= StrTab.size())
279 return createStringError(object_error::parse_failed,
280 "st_name (0x%" PRIx32
281 ") is past the end of the string table"
282 " of size 0x%zx",
283 Offset, StrTab.size());
284 return StringRef(StrTab.data() + Offset);
285}
286
287/// Elf_Versym: This is the structure of entries in the SHT_GNU_versym section
288/// (.gnu.version). This structure is identical for ELF32 and ELF64.
289template <class ELFT>
290struct Elf_Versym_Impl {
291 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT)
292 Elf_Half vs_index; // Version index with flags (e.g. VERSYM_HIDDEN)
293};
294
295/// Elf_Verdef: This is the structure of entries in the SHT_GNU_verdef section
296/// (.gnu.version_d). This structure is identical for ELF32 and ELF64.
297template <class ELFT>
298struct Elf_Verdef_Impl {
299 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT)
300 Elf_Half vd_version; // Version of this structure (e.g. VER_DEF_CURRENT)
301 Elf_Half vd_flags; // Bitwise flags (VER_DEF_*)
302 Elf_Half vd_ndx; // Version index, used in .gnu.version entries
303 Elf_Half vd_cnt; // Number of Verdaux entries
304 Elf_Word vd_hash; // Hash of name
305 Elf_Word vd_aux; // Offset to the first Verdaux entry (in bytes)
306 Elf_Word vd_next; // Offset to the next Verdef entry (in bytes)
307
308 /// Get the first Verdaux entry for this Verdef.
309 const Elf_Verdaux *getAux() const {
310 return reinterpret_cast<const Elf_Verdaux *>((const char *)this + vd_aux);
311 }
312};
313
314/// Elf_Verdaux: This is the structure of auxiliary data in the SHT_GNU_verdef
315/// section (.gnu.version_d). This structure is identical for ELF32 and ELF64.
316template <class ELFT>
317struct Elf_Verdaux_Impl {
318 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT)
319 Elf_Word vda_name; // Version name (offset in string table)
320 Elf_Word vda_next; // Offset to next Verdaux entry (in bytes)
321};
322
323/// Elf_Verneed: This is the structure of entries in the SHT_GNU_verneed
324/// section (.gnu.version_r). This structure is identical for ELF32 and ELF64.
325template <class ELFT>
326struct Elf_Verneed_Impl {
327 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT)
328 Elf_Half vn_version; // Version of this structure (e.g. VER_NEED_CURRENT)
329 Elf_Half vn_cnt; // Number of associated Vernaux entries
330 Elf_Word vn_file; // Library name (string table offset)
331 Elf_Word vn_aux; // Offset to first Vernaux entry (in bytes)
332 Elf_Word vn_next; // Offset to next Verneed entry (in bytes)
333};
334
335/// Elf_Vernaux: This is the structure of auxiliary data in SHT_GNU_verneed
336/// section (.gnu.version_r). This structure is identical for ELF32 and ELF64.
337template <class ELFT>
338struct Elf_Vernaux_Impl {
339 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT)
340 Elf_Word vna_hash; // Hash of dependency name
341 Elf_Half vna_flags; // Bitwise Flags (VER_FLAG_*)
342 Elf_Half vna_other; // Version index, used in .gnu.version entries
343 Elf_Word vna_name; // Dependency name
344 Elf_Word vna_next; // Offset to next Vernaux entry (in bytes)
345};
346
347/// Elf_Dyn_Base: This structure matches the form of entries in the dynamic
348/// table section (.dynamic) look like.
349template <class ELFT> struct Elf_Dyn_Base;
350
351template <endianness TargetEndianness>
352struct Elf_Dyn_Base<ELFType<TargetEndianness, false>> {
353 LLVM_ELF_IMPORT_TYPES(TargetEndianness, false)
354 Elf_Sword d_tag;
355 union {
356 Elf_Word d_val;
357 Elf_Addr d_ptr;
358 } d_un;
359};
360
361template <endianness TargetEndianness>
362struct Elf_Dyn_Base<ELFType<TargetEndianness, true>> {
363 LLVM_ELF_IMPORT_TYPES(TargetEndianness, true)
364 Elf_Sxword d_tag;
365 union {
366 Elf_Xword d_val;
367 Elf_Addr d_ptr;
368 } d_un;
369};
370
371/// Elf_Dyn_Impl: This inherits from Elf_Dyn_Base, adding getters.
372template <class ELFT>
373struct Elf_Dyn_Impl : Elf_Dyn_Base<ELFT> {
374 using Elf_Dyn_Base<ELFT>::d_tag;
375 using Elf_Dyn_Base<ELFT>::d_un;
376 using intX_t = std::conditional_t<ELFT::Is64Bits, int64_t, int32_t>;
377 using uintX_t = std::conditional_t<ELFT::Is64Bits, uint64_t, uint32_t>;
378 intX_t getTag() const { return d_tag; }
379 uintX_t getVal() const { return d_un.d_val; }
380 uintX_t getPtr() const { return d_un.d_ptr; }
381};
382
383template <endianness TargetEndianness>
384struct Elf_Rel_Impl<ELFType<TargetEndianness, false>, false> {
385 LLVM_ELF_IMPORT_TYPES(TargetEndianness, false)
386 static const bool IsRela = false;
387 Elf_Addr r_offset; // Location (file byte offset, or program virtual addr)
388 Elf_Word r_info; // Symbol table index and type of relocation to apply
389
390 uint32_t getRInfo(bool isMips64EL) const {
391 assert(!isMips64EL);
392 return r_info;
393 }
394 void setRInfo(uint32_t R, bool IsMips64EL) {
395 assert(!IsMips64EL);
396 r_info = R;
397 }
398
399 // These accessors and mutators correspond to the ELF32_R_SYM, ELF32_R_TYPE,
400 // and ELF32_R_INFO macros defined in the ELF specification:
401 uint32_t getSymbol(bool isMips64EL) const {
402 return this->getRInfo(isMips64EL) >> 8;
403 }
404 unsigned char getType(bool isMips64EL) const {
405 return (unsigned char)(this->getRInfo(isMips64EL) & 0x0ff);
406 }
407 void setSymbol(uint32_t s, bool IsMips64EL) {
408 setSymbolAndType(s, getType(IsMips64EL), IsMips64EL);
409 }
410 void setType(unsigned char t, bool IsMips64EL) {
411 setSymbolAndType(getSymbol(IsMips64EL), t, IsMips64EL);
412 }
413 void setSymbolAndType(uint32_t s, unsigned char t, bool IsMips64EL) {
414 this->setRInfo((s << 8) + t, IsMips64EL);
415 }
416};
417
418template <endianness TargetEndianness>
419struct Elf_Rel_Impl<ELFType<TargetEndianness, false>, true>
420 : public Elf_Rel_Impl<ELFType<TargetEndianness, false>, false> {
421 LLVM_ELF_IMPORT_TYPES(TargetEndianness, false)
422 static const bool IsRela = true;
423 Elf_Sword r_addend; // Compute value for relocatable field by adding this
424};
425
426template <endianness TargetEndianness>
427struct Elf_Rel_Impl<ELFType<TargetEndianness, true>, false> {
428 LLVM_ELF_IMPORT_TYPES(TargetEndianness, true)
429 static const bool IsRela = false;
430 Elf_Addr r_offset; // Location (file byte offset, or program virtual addr)
431 Elf_Xword r_info; // Symbol table index and type of relocation to apply
432
433 uint64_t getRInfo(bool isMips64EL) const {
434 uint64_t t = r_info;
435 if (!isMips64EL)
436 return t;
437 // Mips64 little endian has a "special" encoding of r_info. Instead of one
438 // 64 bit little endian number, it is a little endian 32 bit number followed
439 // by a 32 bit big endian number.
440 return (t << 32) | ((t >> 8) & 0xff000000) | ((t >> 24) & 0x00ff0000) |
441 ((t >> 40) & 0x0000ff00) | ((t >> 56) & 0x000000ff);
442 }
443
444 void setRInfo(uint64_t R, bool IsMips64EL) {
445 if (IsMips64EL)
446 r_info = (R >> 32) | ((R & 0xff000000) << 8) | ((R & 0x00ff0000) << 24) |
447 ((R & 0x0000ff00) << 40) | ((R & 0x000000ff) << 56);
448 else
449 r_info = R;
450 }
451
452 // These accessors and mutators correspond to the ELF64_R_SYM, ELF64_R_TYPE,
453 // and ELF64_R_INFO macros defined in the ELF specification:
454 uint32_t getSymbol(bool isMips64EL) const {
455 return (uint32_t)(this->getRInfo(isMips64EL) >> 32);
456 }
457 uint32_t getType(bool isMips64EL) const {
458 return (uint32_t)(this->getRInfo(isMips64EL) & 0xffffffffL);
459 }
460 void setSymbol(uint32_t s, bool IsMips64EL) {
461 setSymbolAndType(s, getType(IsMips64EL), IsMips64EL);
462 }
463 void setType(uint32_t t, bool IsMips64EL) {
464 setSymbolAndType(getSymbol(IsMips64EL), t, IsMips64EL);
465 }
466 void setSymbolAndType(uint32_t s, uint32_t t, bool IsMips64EL) {
467 this->setRInfo(((uint64_t)s << 32) + (t & 0xffffffffL), IsMips64EL);
468 }
469};
470
471template <endianness TargetEndianness>
472struct Elf_Rel_Impl<ELFType<TargetEndianness, true>, true>
473 : public Elf_Rel_Impl<ELFType<TargetEndianness, true>, false> {
474 LLVM_ELF_IMPORT_TYPES(TargetEndianness, true)
475 static const bool IsRela = true;
476 Elf_Sxword r_addend; // Compute value for relocatable field by adding this.
477};
478
479template <class ELFT>
480struct Elf_Ehdr_Impl {
481 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT)
482 unsigned char e_ident[ELF::EI_NIDENT]; // ELF Identification bytes
483 Elf_Half e_type; // Type of file (see ET_*)
484 Elf_Half e_machine; // Required architecture for this file (see EM_*)
485 Elf_Word e_version; // Must be equal to 1
486 Elf_Addr e_entry; // Address to jump to in order to start program
487 Elf_Off e_phoff; // Program header table's file offset, in bytes
488 Elf_Off e_shoff; // Section header table's file offset, in bytes
489 Elf_Word e_flags; // Processor-specific flags
490 Elf_Half e_ehsize; // Size of ELF header, in bytes
491 Elf_Half e_phentsize; // Size of an entry in the program header table
492 Elf_Half e_phnum; // Number of entries in the program header table
493 Elf_Half e_shentsize; // Size of an entry in the section header table
494 Elf_Half e_shnum; // Number of entries in the section header table
495 Elf_Half e_shstrndx; // Section header table index of section name
496 // string table
497
498 bool checkMagic() const {
499 return (memcmp(e_ident, ELF::ElfMagic, strlen(ELF::ElfMagic))) == 0;
500 }
501
502 unsigned char getFileClass() const { return e_ident[ELF::EI_CLASS]; }
503 unsigned char getDataEncoding() const { return e_ident[ELF::EI_DATA]; }
504};
505
506template <endianness TargetEndianness>
507struct Elf_Phdr_Impl<ELFType<TargetEndianness, false>> {
508 LLVM_ELF_IMPORT_TYPES(TargetEndianness, false)
509 Elf_Word p_type; // Type of segment
510 Elf_Off p_offset; // FileOffset where segment is located, in bytes
511 Elf_Addr p_vaddr; // Virtual Address of beginning of segment
512 Elf_Addr p_paddr; // Physical address of beginning of segment (OS-specific)
513 Elf_Word p_filesz; // Num. of bytes in file image of segment (may be zero)
514 Elf_Word p_memsz; // Num. of bytes in mem image of segment (may be zero)
515 Elf_Word p_flags; // Segment flags
516 Elf_Word p_align; // Segment alignment constraint
517};
518
519template <endianness TargetEndianness>
520struct Elf_Phdr_Impl<ELFType<TargetEndianness, true>> {
521 LLVM_ELF_IMPORT_TYPES(TargetEndianness, true)
522 Elf_Word p_type; // Type of segment
523 Elf_Word p_flags; // Segment flags
524 Elf_Off p_offset; // FileOffset where segment is located, in bytes
525 Elf_Addr p_vaddr; // Virtual Address of beginning of segment
526 Elf_Addr p_paddr; // Physical address of beginning of segment (OS-specific)
527 Elf_Xword p_filesz; // Num. of bytes in file image of segment (may be zero)
528 Elf_Xword p_memsz; // Num. of bytes in mem image of segment (may be zero)
529 Elf_Xword p_align; // Segment alignment constraint
530};
531
532// ELFT needed for endianness.
533template <class ELFT>
534struct Elf_Hash_Impl {
535 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT)
536 Elf_Word nbucket;
537 Elf_Word nchain;
538
539 ArrayRef<Elf_Word> buckets() const {
540 return ArrayRef<Elf_Word>(&nbucket + 2, &nbucket + 2 + nbucket);
541 }
542
543 ArrayRef<Elf_Word> chains() const {
544 return ArrayRef<Elf_Word>(&nbucket + 2 + nbucket,
545 &nbucket + 2 + nbucket + nchain);
546 }
547};
548
549// .gnu.hash section
550template <class ELFT>
551struct Elf_GnuHash_Impl {
552 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT)
553 Elf_Word nbuckets;
554 Elf_Word symndx;
555 Elf_Word maskwords;
556 Elf_Word shift2;
557
558 ArrayRef<Elf_Off> filter() const {
559 return ArrayRef<Elf_Off>(reinterpret_cast<const Elf_Off *>(&shift2 + 1),
560 maskwords);
561 }
562
563 ArrayRef<Elf_Word> buckets() const {
564 return ArrayRef<Elf_Word>(
565 reinterpret_cast<const Elf_Word *>(filter().end()), nbuckets);
566 }
567
568 ArrayRef<Elf_Word> values(unsigned DynamicSymCount) const {
569 assert(DynamicSymCount >= symndx);
570 return ArrayRef<Elf_Word>(buckets().end(), DynamicSymCount - symndx);
571 }
572};
573
574// Compressed section headers.
575// http://www.sco.com/developers/gabi/latest/ch4.sheader.html#compression_header
576template <endianness TargetEndianness>
577struct Elf_Chdr_Impl<ELFType<TargetEndianness, false>> {
578 LLVM_ELF_IMPORT_TYPES(TargetEndianness, false)
579 Elf_Word ch_type;
580 Elf_Word ch_size;
581 Elf_Word ch_addralign;
582};
583
584template <endianness TargetEndianness>
585struct Elf_Chdr_Impl<ELFType<TargetEndianness, true>> {
586 LLVM_ELF_IMPORT_TYPES(TargetEndianness, true)
587 Elf_Word ch_type;
588 Elf_Word ch_reserved;
589 Elf_Xword ch_size;
590 Elf_Xword ch_addralign;
591};
592
593/// Note header
594template <class ELFT>
595struct Elf_Nhdr_Impl {
596 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT)
597 Elf_Word n_namesz;
598 Elf_Word n_descsz;
599 Elf_Word n_type;
600
601 /// The alignment of the name and descriptor.
602 ///
603 /// Implementations differ from the specification here: in practice all
604 /// variants align both the name and descriptor to 4-bytes.
605 static const unsigned int Align = 4;
606
607 /// Get the size of the note, including name, descriptor, and padding.
608 size_t getSize() const {
609 return sizeof(*this) + alignTo<Align>(n_namesz) + alignTo<Align>(n_descsz);
610 }
611};
612
613/// An ELF note.
614///
615/// Wraps a note header, providing methods for accessing the name and
616/// descriptor safely.
617template <class ELFT>
618class Elf_Note_Impl {
619 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT)
620
621 const Elf_Nhdr_Impl<ELFT> &Nhdr;
622
623 template <class NoteIteratorELFT> friend class Elf_Note_Iterator_Impl;
624
625public:
626 Elf_Note_Impl(const Elf_Nhdr_Impl<ELFT> &Nhdr) : Nhdr(Nhdr) {}
627
628 /// Get the note's name, excluding the terminating null byte.
629 StringRef getName() const {
630 if (!Nhdr.n_namesz)
631 return StringRef();
632 return StringRef(reinterpret_cast<const char *>(&Nhdr) + sizeof(Nhdr),
633 Nhdr.n_namesz - 1);
634 }
635
636 /// Get the note's descriptor.
637 ArrayRef<uint8_t> getDesc() const {
638 if (!Nhdr.n_descsz)
639 return ArrayRef<uint8_t>();
640 return ArrayRef<uint8_t>(
641 reinterpret_cast<const uint8_t *>(&Nhdr) + sizeof(Nhdr) +
642 alignTo<Elf_Nhdr_Impl<ELFT>::Align>(Nhdr.n_namesz),
643 Nhdr.n_descsz);
644 }
645
646 /// Get the note's descriptor as StringRef
647 StringRef getDescAsStringRef() const {
648 ArrayRef<uint8_t> Desc = getDesc();
649 return StringRef(reinterpret_cast<const char *>(Desc.data()), Desc.size());
650 }
651
652 /// Get the note's type.
653 Elf_Word getType() const { return Nhdr.n_type; }
654};
655
656template <class ELFT> class Elf_Note_Iterator_Impl {
657public:
658 using iterator_category = std::forward_iterator_tag;
659 using value_type = Elf_Note_Impl<ELFT>;
660 using difference_type = std::ptrdiff_t;
661 using pointer = value_type *;
662 using reference = value_type &;
663
664private:
665 // Nhdr being a nullptr marks the end of iteration.
666 const Elf_Nhdr_Impl<ELFT> *Nhdr = nullptr;
667 size_t RemainingSize = 0u;
668 Error *Err = nullptr;
669
670 template <class ELFFileELFT> friend class ELFFile;
671
672 // Stop iteration and indicate an overflow.
673 void stopWithOverflowError() {
674 Nhdr = nullptr;
675 *Err = make_error<StringError>("ELF note overflows container",
676 object_error::parse_failed);
677 }
678
679 // Advance Nhdr by NoteSize bytes, starting from NhdrPos.
680 //
681 // Assumes NoteSize <= RemainingSize. Ensures Nhdr->getSize() <= RemainingSize
682 // upon returning. Handles stopping iteration when reaching the end of the
683 // container, either cleanly or with an overflow error.
684 void advanceNhdr(const uint8_t *NhdrPos, size_t NoteSize) {
685 RemainingSize -= NoteSize;
686 if (RemainingSize == 0u) {
687 // Ensure that if the iterator walks to the end, the error is checked
688 // afterwards.
689 *Err = Error::success();
690 Nhdr = nullptr;
691 } else if (sizeof(*Nhdr) > RemainingSize)
692 stopWithOverflowError();
693 else {
694 Nhdr = reinterpret_cast<const Elf_Nhdr_Impl<ELFT> *>(NhdrPos + NoteSize);
695 if (Nhdr->getSize() > RemainingSize)
696 stopWithOverflowError();
697 else
698 *Err = Error::success();
699 }
700 }
701
702 Elf_Note_Iterator_Impl() = default;
703 explicit Elf_Note_Iterator_Impl(Error &Err) : Err(&Err) {}
704 Elf_Note_Iterator_Impl(const uint8_t *Start, size_t Size, Error &Err)
705 : RemainingSize(Size), Err(&Err) {
706 consumeError(std::move(Err));
707 assert(Start && "ELF note iterator starting at NULL");
708 advanceNhdr(Start, 0u);
709 }
710
711public:
712 Elf_Note_Iterator_Impl &operator++() {
713 assert(Nhdr && "incremented ELF note end iterator");
714 const uint8_t *NhdrPos = reinterpret_cast<const uint8_t *>(Nhdr);
715 size_t NoteSize = Nhdr->getSize();
716 advanceNhdr(NhdrPos, NoteSize);
717 return *this;
718 }
719 bool operator==(Elf_Note_Iterator_Impl Other) const {
720 if (!Nhdr && Other.Err)
721 (void)(bool)(*Other.Err);
722 if (!Other.Nhdr && Err)
723 (void)(bool)(*Err);
724 return Nhdr == Other.Nhdr;
725 }
726 bool operator!=(Elf_Note_Iterator_Impl Other) const {
727 return !(*this == Other);
728 }
729 Elf_Note_Impl<ELFT> operator*() const {
730 assert(Nhdr && "dereferenced ELF note end iterator");
731 return Elf_Note_Impl<ELFT>(*Nhdr);
732 }
733};
734
735template <class ELFT> struct Elf_CGProfile_Impl {
736 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT)
737 Elf_Xword cgp_weight;
738};
739
740// MIPS .reginfo section
741template <class ELFT>
742struct Elf_Mips_RegInfo;
743
744template <support::endianness TargetEndianness>
745struct Elf_Mips_RegInfo<ELFType<TargetEndianness, false>> {
746 LLVM_ELF_IMPORT_TYPES(TargetEndianness, false)
747 Elf_Word ri_gprmask; // bit-mask of used general registers
748 Elf_Word ri_cprmask[4]; // bit-mask of used co-processor registers
749 Elf_Addr ri_gp_value; // gp register value
750};
751
752template <support::endianness TargetEndianness>
753struct Elf_Mips_RegInfo<ELFType<TargetEndianness, true>> {
754 LLVM_ELF_IMPORT_TYPES(TargetEndianness, true)
755 Elf_Word ri_gprmask; // bit-mask of used general registers
756 Elf_Word ri_pad; // unused padding field
757 Elf_Word ri_cprmask[4]; // bit-mask of used co-processor registers
758 Elf_Addr ri_gp_value; // gp register value
759};
760
761// .MIPS.options section
762template <class ELFT> struct Elf_Mips_Options {
763 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT)
764 uint8_t kind; // Determines interpretation of variable part of descriptor
765 uint8_t size; // Byte size of descriptor, including this header
766 Elf_Half section; // Section header index of section affected,
767 // or 0 for global options
768 Elf_Word info; // Kind-specific information
769
770 Elf_Mips_RegInfo<ELFT> &getRegInfo() {
771 assert(kind == ELF::ODK_REGINFO);
772 return *reinterpret_cast<Elf_Mips_RegInfo<ELFT> *>(
773 (uint8_t *)this + sizeof(Elf_Mips_Options));
774 }
775 const Elf_Mips_RegInfo<ELFT> &getRegInfo() const {
776 return const_cast<Elf_Mips_Options *>(this)->getRegInfo();
777 }
778};
779
780// .MIPS.abiflags section content
781template <class ELFT> struct Elf_Mips_ABIFlags {
782 LLVM_ELF_IMPORT_TYPES_ELFT(ELFT)
783 Elf_Half version; // Version of the structure
784 uint8_t isa_level; // ISA level: 1-5, 32, and 64
785 uint8_t isa_rev; // ISA revision (0 for MIPS I - MIPS V)
786 uint8_t gpr_size; // General purpose registers size
787 uint8_t cpr1_size; // Co-processor 1 registers size
788 uint8_t cpr2_size; // Co-processor 2 registers size
789 uint8_t fp_abi; // Floating-point ABI flag
790 Elf_Word isa_ext; // Processor-specific extension
791 Elf_Word ases; // ASEs flags
792 Elf_Word flags1; // General flags
793 Elf_Word flags2; // General flags
794};
795
796// Struct representing the BBAddrMap for one function.
797struct BBAddrMap {
798 uint64_t Addr; // Function address
799 // Struct representing the BBAddrMap information for one basic block.
800 struct BBEntry {
801 uint32_t Offset; // Offset of basic block relative to function start.
802 uint32_t Size; // Size of the basic block.
803
804 // The following fields are decoded from the Metadata field. The encoding
805 // happens in AsmPrinter.cpp:getBBAddrMapMetadata.
806 bool HasReturn; // If this block ends with a return (or tail call).
807 bool HasTailCall; // If this block ends with a tail call.
808 bool IsEHPad; // If this is an exception handling block.
809 bool CanFallThrough; // If this block can fall through to its next.
810
811 BBEntry(uint32_t Offset, uint32_t Size, uint32_t Metadata)
812 : Offset(Offset), Size(Size), HasReturn(Metadata & 1),
813 HasTailCall(Metadata & (1 << 1)), IsEHPad(Metadata & (1 << 2)),
814 CanFallThrough(Metadata & (1 << 3)){};
815
816 bool operator==(const BBEntry &Other) const {
817 return Offset == Other.Offset && Size == Other.Size &&
818 HasReturn == Other.HasReturn && HasTailCall == Other.HasTailCall &&
819 IsEHPad == Other.IsEHPad && CanFallThrough == Other.CanFallThrough;
820 }
821 };
822 std::vector<BBEntry> BBEntries; // Basic block entries for this function.
823
824 // Equality operator for unit testing.
825 bool operator==(const BBAddrMap &Other) const {
826 return Addr == Other.Addr && std::equal(BBEntries.begin(), BBEntries.end(),
827 Other.BBEntries.begin());
828 }
829};
830
831} // end namespace object.
832} // end namespace llvm.
833
834#endif // LLVM_OBJECT_ELFTYPES_H
835

source code of llvm/include/llvm/Object/ELFTypes.h