| 1 | // elfcpp_file.h -- file access for elfcpp -*- C++ -*- |
| 2 | |
| 3 | // Copyright 2006, 2007, Free Software Foundation, Inc. |
| 4 | // Written by Ian Lance Taylor <iant@google.com>. |
| 5 | |
| 6 | // This file is part of elfcpp. |
| 7 | |
| 8 | // This program is free software; you can redistribute it and/or |
| 9 | // modify it under the terms of the GNU Library General Public License |
| 10 | // as published by the Free Software Foundation; either version 2, or |
| 11 | // (at your option) any later version. |
| 12 | |
| 13 | // In addition to the permissions in the GNU Library General Public |
| 14 | // License, the Free Software Foundation gives you unlimited |
| 15 | // permission to link the compiled version of this file into |
| 16 | // combinations with other programs, and to distribute those |
| 17 | // combinations without any restriction coming from the use of this |
| 18 | // file. (The Library Public License restrictions do apply in other |
| 19 | // respects; for example, they cover modification of the file, and |
| 20 | /// distribution when not linked into a combined executable.) |
| 21 | |
| 22 | // This program is distributed in the hope that it will be useful, but |
| 23 | // WITHOUT ANY WARRANTY; without even the implied warranty of |
| 24 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 25 | // Library General Public License for more details. |
| 26 | |
| 27 | // You should have received a copy of the GNU Library General Public |
| 28 | // License along with this program; if not, write to the Free Software |
| 29 | // Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA |
| 30 | // 02110-1301, USA. |
| 31 | |
| 32 | // This header file defines the class Elf_file which can be used to |
| 33 | // read useful data from an ELF file. The functions here are all |
| 34 | // templates which take a file interface object as a parameter. This |
| 35 | // type must have a subtype View. This type must support two methods: |
| 36 | // View view(off_t file_offset, off_t data_size) |
| 37 | // returns a View for the specified part of the file. |
| 38 | // void error(const char* printf_format, ...) |
| 39 | // prints an error message and does not return. The subtype View must |
| 40 | // support a method |
| 41 | // const unsigned char* data() |
| 42 | // which returns a pointer to a buffer containing the requested data. |
| 43 | // This general interface is used to read data from the file. Objects |
| 44 | // of type View will never survive longer than the elfcpp function. |
| 45 | |
| 46 | // Some of these functions must return a reference to part of the |
| 47 | // file. To use these, the file interface must support a subtype |
| 48 | // Location: |
| 49 | // Location(off_t file_offset, off_t data_size) |
| 50 | // To use this in conjunction with the accessors types Shdr, etc., the |
| 51 | // file interface should support an overload of view: |
| 52 | // View view(Location) |
| 53 | // This permits writing |
| 54 | // elfcpp::Shdr shdr(file, ef.section_header(n)); |
| 55 | |
| 56 | #ifndef ELFCPP_FILE_H |
| 57 | #define ELFCPP_FILE_H |
| 58 | |
| 59 | #include <string> |
| 60 | #include <cstdio> |
| 61 | #include <cstring> |
| 62 | |
| 63 | #include "elfcpp.h" |
| 64 | |
| 65 | namespace elfcpp |
| 66 | { |
| 67 | |
| 68 | // A simple helper class to recognize if a file has an ELF header. |
| 69 | |
| 70 | class Elf_recognizer |
| 71 | { |
| 72 | public: |
| 73 | // Maximum header size. The user should try to read this much of |
| 74 | // the file when using this class. |
| 75 | |
| 76 | static const int max_header_size = Elf_sizes<64>::ehdr_size; |
| 77 | |
| 78 | // Checks if the file contains the ELF magic. Other header fields |
| 79 | // are not checked. |
| 80 | |
| 81 | static bool |
| 82 | is_elf_file(const unsigned char* ehdr_buf, int size); |
| 83 | |
| 84 | // Check if EHDR_BUF/BUFSIZE is a valid header of a 32-bit or |
| 85 | // 64-bit, little-endian or big-endian ELF file. Assumes |
| 86 | // is_elf_file() has been checked to be true. If the header is not |
| 87 | // valid, *ERROR contains a human-readable error message. If is is, |
| 88 | // *SIZE is set to either 32 or 64, *BIG_ENDIAN is set to indicate |
| 89 | // whether the file is big-endian. |
| 90 | |
| 91 | static bool |
| 92 | is_valid_header(const unsigned char* ehdr_buf, off_t bufsize, |
| 93 | int* size, bool* big_endian, |
| 94 | std::string* error); |
| 95 | }; |
| 96 | |
| 97 | // This object is used to read an ELF file. |
| 98 | // SIZE: The size of file, 32 or 64. |
| 99 | // BIG_ENDIAN: Whether the file is in big-endian format. |
| 100 | // FILE: A file reading type as described above. |
| 101 | |
| 102 | template<int size, bool big_endian, typename File> |
| 103 | class Elf_file |
| 104 | { |
| 105 | private: |
| 106 | typedef Elf_file<size, big_endian, File> This; |
| 107 | |
| 108 | public: |
| 109 | static const int ehdr_size = Elf_sizes<size>::ehdr_size; |
| 110 | static const int phdr_size = Elf_sizes<size>::phdr_size; |
| 111 | static const int shdr_size = Elf_sizes<size>::shdr_size; |
| 112 | static const int sym_size = Elf_sizes<size>::sym_size; |
| 113 | static const int rel_size = Elf_sizes<size>::rel_size; |
| 114 | static const int rela_size = Elf_sizes<size>::rela_size; |
| 115 | |
| 116 | typedef Ehdr<size, big_endian> Ef_ehdr; |
| 117 | typedef Phdr<size, big_endian> Ef_phdr; |
| 118 | typedef Shdr<size, big_endian> Ef_shdr; |
| 119 | typedef Sym<size, big_endian> Ef_sym; |
| 120 | |
| 121 | // Construct an Elf_file given an ELF file header. |
| 122 | Elf_file(File* file, const Ef_ehdr& ehdr) |
| 123 | { this->construct(file, ehdr); } |
| 124 | |
| 125 | // Construct an ELF file. |
| 126 | inline |
| 127 | Elf_file(File* file); |
| 128 | |
| 129 | // Return the file offset to the section headers. |
| 130 | off_t |
| 131 | shoff() const |
| 132 | { return this->shoff_; } |
| 133 | |
| 134 | // Find the first section with an sh_type field equal to TYPE and |
| 135 | // return its index. Returns SHN_UNDEF if there is no such section. |
| 136 | unsigned int |
| 137 | find_section_by_type(unsigned int type); |
| 138 | |
| 139 | // Return the number of sections. |
| 140 | unsigned int |
| 141 | shnum() |
| 142 | { |
| 143 | this->initialize_shnum(); |
| 144 | return this->shnum_; |
| 145 | } |
| 146 | |
| 147 | // Return the section index of the section name string table. |
| 148 | unsigned int |
| 149 | shstrndx() |
| 150 | { |
| 151 | this->initialize_shnum(); |
| 152 | return this->shstrndx_; |
| 153 | } |
| 154 | |
| 155 | // Return the value to subtract from section indexes >= |
| 156 | // SHN_LORESERVE. See the comment in initialize_shnum. |
| 157 | int |
| 158 | large_shndx_offset() |
| 159 | { |
| 160 | this->initialize_shnum(); |
| 161 | return this->large_shndx_offset_; |
| 162 | } |
| 163 | |
| 164 | // Return the location of the header of section SHNDX. |
| 165 | typename File::Location |
| 166 | section_header(unsigned int shndx) |
| 167 | { |
| 168 | return typename File::Location(this->section_header_offset(shndx), |
| 169 | shdr_size); |
| 170 | } |
| 171 | |
| 172 | // Return the name of section SHNDX. |
| 173 | std::string |
| 174 | section_name(unsigned int shndx); |
| 175 | |
| 176 | // Return the location of the contents of section SHNDX. |
| 177 | typename File::Location |
| 178 | section_contents(unsigned int shndx); |
| 179 | |
| 180 | // Return the size of section SHNDX. |
| 181 | typename Elf_types<size>::Elf_WXword |
| 182 | section_size(unsigned int shndx); |
| 183 | |
| 184 | // Return the flags of section SHNDX. |
| 185 | typename Elf_types<size>::Elf_WXword |
| 186 | section_flags(unsigned int shndx); |
| 187 | |
| 188 | // Return the address of section SHNDX. |
| 189 | typename Elf_types<size>::Elf_Addr |
| 190 | section_addr(unsigned int shndx); |
| 191 | |
| 192 | // Return the type of section SHNDX. |
| 193 | Elf_Word |
| 194 | section_type(unsigned int shndx); |
| 195 | |
| 196 | // Return the link field of section SHNDX. |
| 197 | Elf_Word |
| 198 | section_link(unsigned int shndx); |
| 199 | |
| 200 | // Return the info field of section SHNDX. |
| 201 | Elf_Word |
| 202 | section_info(unsigned int shndx); |
| 203 | |
| 204 | // Return the addralign field of section SHNDX. |
| 205 | typename Elf_types<size>::Elf_WXword |
| 206 | section_addralign(unsigned int shndx); |
| 207 | |
| 208 | private: |
| 209 | // Shared constructor code. |
| 210 | void |
| 211 | construct(File* file, const Ef_ehdr& ehdr); |
| 212 | |
| 213 | // Initialize shnum_ and shstrndx_. |
| 214 | void |
| 215 | initialize_shnum(); |
| 216 | |
| 217 | // Return the file offset of the header of section SHNDX. |
| 218 | off_t |
| 219 | section_header_offset(unsigned int shndx); |
| 220 | |
| 221 | // The file we are reading. |
| 222 | File* file_; |
| 223 | // The file offset to the section headers. |
| 224 | off_t shoff_; |
| 225 | // The number of sections. |
| 226 | unsigned int shnum_; |
| 227 | // The section index of the section name string table. |
| 228 | unsigned int shstrndx_; |
| 229 | // Offset to add to sections larger than SHN_LORESERVE. |
| 230 | int large_shndx_offset_; |
| 231 | }; |
| 232 | |
| 233 | // A small wrapper around SHT_STRTAB data mapped to memory. It checks that the |
| 234 | // index is not out of bounds and the string is NULL-terminated. |
| 235 | |
| 236 | class Elf_strtab |
| 237 | { |
| 238 | public: |
| 239 | // Construct an Elf_strtab for a section with contents *P and size SIZE. |
| 240 | Elf_strtab(const unsigned char* p, size_t size); |
| 241 | |
| 242 | // Return the file offset to the section headers. |
| 243 | bool |
| 244 | get_c_string(size_t offset, const char** cstring) const |
| 245 | { |
| 246 | if (offset >= this->usable_size_) |
| 247 | return false; |
| 248 | *cstring = this->base_ + offset; |
| 249 | return true; |
| 250 | } |
| 251 | |
| 252 | private: |
| 253 | // Contents of the section mapped to memory. |
| 254 | const char* base_; |
| 255 | // One larger that the position of the last NULL character in the section. |
| 256 | // For valid SHT_STRTAB sections, this is the size of the section. |
| 257 | size_t usable_size_; |
| 258 | }; |
| 259 | |
| 260 | // Inline function definitions. |
| 261 | |
| 262 | // Check for presence of the ELF magic number. |
| 263 | |
| 264 | inline bool |
| 265 | Elf_recognizer::is_elf_file(const unsigned char* ehdr_buf, int size) |
| 266 | { |
| 267 | if (size < 4) |
| 268 | return false; |
| 269 | |
| 270 | static unsigned char elfmagic[4] = |
| 271 | { |
| 272 | elfcpp::ELFMAG0, elfcpp::ELFMAG1, |
| 273 | elfcpp::ELFMAG2, elfcpp::ELFMAG3 |
| 274 | }; |
| 275 | return memcmp(ehdr_buf, elfmagic, 4) == 0; |
| 276 | } |
| 277 | |
| 278 | namespace |
| 279 | { |
| 280 | |
| 281 | // Print a number to a string. |
| 282 | |
| 283 | inline std::string |
| 284 | internal_printf_int(const char* format, int arg) |
| 285 | { |
| 286 | char buf[256]; |
| 287 | snprintf(buf, sizeof(buf), format, arg); |
| 288 | return std::string(buf); |
| 289 | } |
| 290 | |
| 291 | } // End anonymous namespace. |
| 292 | |
| 293 | // Check the validity of the ELF header. |
| 294 | |
| 295 | inline bool |
| 296 | Elf_recognizer::is_valid_header( |
| 297 | const unsigned char* ehdr_buf, |
| 298 | off_t bufsize, |
| 299 | int* size, |
| 300 | bool* big_endian, |
| 301 | std::string* error) |
| 302 | { |
| 303 | if (bufsize < elfcpp::EI_NIDENT) |
| 304 | { |
| 305 | *error = _("ELF file too short"); |
| 306 | return false; |
| 307 | } |
| 308 | |
| 309 | int v = ehdr_buf[elfcpp::EI_VERSION]; |
| 310 | if (v != elfcpp::EV_CURRENT) |
| 311 | { |
| 312 | if (v == elfcpp::EV_NONE) |
| 313 | *error = _("invalid ELF version 0"); |
| 314 | else |
| 315 | *error = internal_printf_int(_("unsupported ELF version %d"), v); |
| 316 | return false; |
| 317 | } |
| 318 | |
| 319 | int c = ehdr_buf[elfcpp::EI_CLASS]; |
| 320 | if (c == elfcpp::ELFCLASSNONE) |
| 321 | { |
| 322 | *error = _("invalid ELF class 0"); |
| 323 | return false; |
| 324 | } |
| 325 | else if (c != elfcpp::ELFCLASS32 |
| 326 | && c != elfcpp::ELFCLASS64) |
| 327 | { |
| 328 | *error = internal_printf_int(_("unsupported ELF class %d"), c); |
| 329 | return false; |
| 330 | } |
| 331 | |
| 332 | int d = ehdr_buf[elfcpp::EI_DATA]; |
| 333 | if (d == elfcpp::ELFDATANONE) |
| 334 | { |
| 335 | *error = _("invalid ELF data encoding"); |
| 336 | return false; |
| 337 | } |
| 338 | else if (d != elfcpp::ELFDATA2LSB |
| 339 | && d != elfcpp::ELFDATA2MSB) |
| 340 | { |
| 341 | *error = internal_printf_int(_("unsupported ELF data encoding %d"), d); |
| 342 | return false; |
| 343 | } |
| 344 | |
| 345 | *big_endian = (d == elfcpp::ELFDATA2MSB); |
| 346 | |
| 347 | if (c == elfcpp::ELFCLASS32) |
| 348 | { |
| 349 | if (bufsize < elfcpp::Elf_sizes<32>::ehdr_size) |
| 350 | { |
| 351 | *error = _("ELF file too short"); |
| 352 | return false; |
| 353 | } |
| 354 | *size = 32; |
| 355 | } |
| 356 | else |
| 357 | { |
| 358 | if (bufsize < elfcpp::Elf_sizes<64>::ehdr_size) |
| 359 | { |
| 360 | *error = _("ELF file too short"); |
| 361 | return false; |
| 362 | } |
| 363 | *size = 64; |
| 364 | } |
| 365 | |
| 366 | return true; |
| 367 | } |
| 368 | |
| 369 | // Template function definitions. |
| 370 | |
| 371 | // Construct an Elf_file given an ELF file header. |
| 372 | |
| 373 | template<int size, bool big_endian, typename File> |
| 374 | void |
| 375 | Elf_file<size, big_endian, File>::construct(File* file, const Ef_ehdr& ehdr) |
| 376 | { |
| 377 | this->file_ = file; |
| 378 | this->shoff_ = ehdr.get_e_shoff(); |
| 379 | this->shnum_ = ehdr.get_e_shnum(); |
| 380 | this->shstrndx_ = ehdr.get_e_shstrndx(); |
| 381 | this->large_shndx_offset_ = 0; |
| 382 | if (ehdr.get_e_ehsize() != This::ehdr_size) |
| 383 | file->error(_("bad e_ehsize (%d != %d)"), |
| 384 | ehdr.get_e_ehsize(), This::ehdr_size); |
| 385 | if (ehdr.get_e_shentsize() != This::shdr_size) |
| 386 | file->error(_("bad e_shentsize (%d != %d)"), |
| 387 | ehdr.get_e_shentsize(), This::shdr_size); |
| 388 | } |
| 389 | |
| 390 | // Construct an ELF file. |
| 391 | |
| 392 | template<int size, bool big_endian, typename File> |
| 393 | inline |
| 394 | Elf_file<size, big_endian, File>::Elf_file(File* file) |
| 395 | { |
| 396 | typename File::View v(file->view(file_header_offset, This::ehdr_size)); |
| 397 | this->construct(file, Ef_ehdr(v.data())); |
| 398 | } |
| 399 | |
| 400 | // Initialize the shnum_ and shstrndx_ fields, handling overflow. |
| 401 | |
| 402 | template<int size, bool big_endian, typename File> |
| 403 | void |
| 404 | Elf_file<size, big_endian, File>::initialize_shnum() |
| 405 | { |
| 406 | if ((this->shnum_ == 0 || this->shstrndx_ == SHN_XINDEX) |
| 407 | && this->shoff_ != 0) |
| 408 | { |
| 409 | typename File::View v(this->file_->view(this->shoff_, This::shdr_size)); |
| 410 | Ef_shdr shdr(v.data()); |
| 411 | |
| 412 | if (this->shnum_ == 0) |
| 413 | this->shnum_ = shdr.get_sh_size(); |
| 414 | |
| 415 | if (this->shstrndx_ == SHN_XINDEX) |
| 416 | { |
| 417 | this->shstrndx_ = shdr.get_sh_link(); |
| 418 | |
| 419 | // Versions of the GNU binutils between 2.12 and 2.18 did |
| 420 | // not handle objects with more than SHN_LORESERVE sections |
| 421 | // correctly. All large section indexes were offset by |
| 422 | // 0x100. Some information can be found here: |
| 423 | // http://sourceware.org/bugzilla/show_bug.cgi?id=5900 . |
| 424 | // Fortunately these object files are easy to detect, as the |
| 425 | // GNU binutils always put the section header string table |
| 426 | // near the end of the list of sections. Thus if the |
| 427 | // section header string table index is larger than the |
| 428 | // number of sections, then we know we have to subtract |
| 429 | // 0x100 to get the real section index. |
| 430 | if (this->shstrndx_ >= this->shnum_) |
| 431 | { |
| 432 | if (this->shstrndx_ >= elfcpp::SHN_LORESERVE + 0x100) |
| 433 | { |
| 434 | this->large_shndx_offset_ = - 0x100; |
| 435 | this->shstrndx_ -= 0x100; |
| 436 | } |
| 437 | if (this->shstrndx_ >= this->shnum_) |
| 438 | this->file_->error(_("bad shstrndx: %u >= %u"), |
| 439 | this->shstrndx_, this->shnum_); |
| 440 | } |
| 441 | } |
| 442 | } |
| 443 | } |
| 444 | |
| 445 | // Find section with sh_type equal to TYPE and return its index. |
| 446 | // Returns SHN_UNDEF if not found. |
| 447 | |
| 448 | template<int size, bool big_endian, typename File> |
| 449 | unsigned int |
| 450 | Elf_file<size, big_endian, File>::find_section_by_type(unsigned int type) |
| 451 | { |
| 452 | unsigned int shnum = this->shnum(); |
| 453 | typename File::View v(this->file_->view(this->shoff_, |
| 454 | This::shdr_size * shnum)); |
| 455 | for (unsigned int i = 0; i < shnum; i++) |
| 456 | { |
| 457 | Ef_shdr shdr(v.data() + This::shdr_size * i); |
| 458 | if (shdr.get_sh_type() == type) |
| 459 | return i; |
| 460 | } |
| 461 | return SHN_UNDEF; |
| 462 | } |
| 463 | |
| 464 | // Return the file offset of the section header of section SHNDX. |
| 465 | |
| 466 | template<int size, bool big_endian, typename File> |
| 467 | off_t |
| 468 | Elf_file<size, big_endian, File>::section_header_offset(unsigned int shndx) |
| 469 | { |
| 470 | if (shndx >= this->shnum()) |
| 471 | this->file_->error(_("section_header_offset: bad shndx %u >= %u"), |
| 472 | shndx, this->shnum()); |
| 473 | return this->shoff_ + This::shdr_size * shndx; |
| 474 | } |
| 475 | |
| 476 | // Return the name of section SHNDX. |
| 477 | |
| 478 | template<int size, bool big_endian, typename File> |
| 479 | std::string |
| 480 | Elf_file<size, big_endian, File>::section_name(unsigned int shndx) |
| 481 | { |
| 482 | File* const file = this->file_; |
| 483 | |
| 484 | // Get the section name offset. |
| 485 | unsigned int sh_name; |
| 486 | { |
| 487 | typename File::View v(file->view(this->section_header_offset(shndx), |
| 488 | This::shdr_size)); |
| 489 | Ef_shdr shdr(v.data()); |
| 490 | sh_name = shdr.get_sh_name(); |
| 491 | } |
| 492 | |
| 493 | // Get the file offset for the section name string table data. |
| 494 | off_t shstr_off; |
| 495 | typename Elf_types<size>::Elf_WXword shstr_size; |
| 496 | { |
| 497 | const unsigned int shstrndx = this->shstrndx_; |
| 498 | typename File::View v(file->view(this->section_header_offset(shstrndx), |
| 499 | This::shdr_size)); |
| 500 | Ef_shdr shstr_shdr(v.data()); |
| 501 | shstr_off = shstr_shdr.get_sh_offset(); |
| 502 | shstr_size = shstr_shdr.get_sh_size(); |
| 503 | } |
| 504 | |
| 505 | if (sh_name >= shstr_size) |
| 506 | file->error(_("bad section name offset for section %u: %u"), |
| 507 | shndx, sh_name); |
| 508 | |
| 509 | typename File::View v(file->view(shstr_off, shstr_size)); |
| 510 | |
| 511 | const unsigned char* datau = v.data(); |
| 512 | const char* data = reinterpret_cast<const char*>(datau); |
| 513 | const void* p = ::memchr(data + sh_name, '\0', shstr_size - sh_name); |
| 514 | if (p == NULL) |
| 515 | file->error(_("missing null terminator for name of section %u"), |
| 516 | shndx); |
| 517 | |
| 518 | size_t len = static_cast<const char*>(p) - (data + sh_name); |
| 519 | |
| 520 | return std::string(data + sh_name, len); |
| 521 | } |
| 522 | |
| 523 | // Return the contents of section SHNDX. |
| 524 | |
| 525 | template<int size, bool big_endian, typename File> |
| 526 | typename File::Location |
| 527 | Elf_file<size, big_endian, File>::section_contents(unsigned int shndx) |
| 528 | { |
| 529 | File* const file = this->file_; |
| 530 | |
| 531 | if (shndx >= this->shnum()) |
| 532 | file->error(_("section_contents: bad shndx %u >= %u"), |
| 533 | shndx, this->shnum()); |
| 534 | |
| 535 | typename File::View v(file->view(this->section_header_offset(shndx), |
| 536 | This::shdr_size)); |
| 537 | Ef_shdr shdr(v.data()); |
| 538 | return typename File::Location(shdr.get_sh_offset(), shdr.get_sh_size()); |
| 539 | } |
| 540 | |
| 541 | // Get the size of section SHNDX. |
| 542 | |
| 543 | template<int size, bool big_endian, typename File> |
| 544 | typename Elf_types<size>::Elf_WXword |
| 545 | Elf_file<size, big_endian, File>::section_size(unsigned int shndx) |
| 546 | { |
| 547 | File* const file = this->file_; |
| 548 | |
| 549 | if (shndx >= this->shnum()) |
| 550 | file->error(_("section_size: bad shndx %u >= %u"), |
| 551 | shndx, this->shnum()); |
| 552 | |
| 553 | typename File::View v(file->view(this->section_header_offset(shndx), |
| 554 | This::shdr_size)); |
| 555 | |
| 556 | Ef_shdr shdr(v.data()); |
| 557 | return shdr.get_sh_size(); |
| 558 | } |
| 559 | |
| 560 | // Return the section flags of section SHNDX. |
| 561 | |
| 562 | template<int size, bool big_endian, typename File> |
| 563 | typename Elf_types<size>::Elf_WXword |
| 564 | Elf_file<size, big_endian, File>::section_flags(unsigned int shndx) |
| 565 | { |
| 566 | File* const file = this->file_; |
| 567 | |
| 568 | if (shndx >= this->shnum()) |
| 569 | file->error(_("section_flags: bad shndx %u >= %u"), |
| 570 | shndx, this->shnum()); |
| 571 | |
| 572 | typename File::View v(file->view(this->section_header_offset(shndx), |
| 573 | This::shdr_size)); |
| 574 | |
| 575 | Ef_shdr shdr(v.data()); |
| 576 | return shdr.get_sh_flags(); |
| 577 | } |
| 578 | |
| 579 | // Return the address of section SHNDX. |
| 580 | |
| 581 | template<int size, bool big_endian, typename File> |
| 582 | typename Elf_types<size>::Elf_Addr |
| 583 | Elf_file<size, big_endian, File>::section_addr(unsigned int shndx) |
| 584 | { |
| 585 | File* const file = this->file_; |
| 586 | |
| 587 | if (shndx >= this->shnum()) |
| 588 | file->error(_("section_flags: bad shndx %u >= %u"), |
| 589 | shndx, this->shnum()); |
| 590 | |
| 591 | typename File::View v(file->view(this->section_header_offset(shndx), |
| 592 | This::shdr_size)); |
| 593 | |
| 594 | Ef_shdr shdr(v.data()); |
| 595 | return shdr.get_sh_addr(); |
| 596 | } |
| 597 | |
| 598 | // Return the type of section SHNDX. |
| 599 | |
| 600 | template<int size, bool big_endian, typename File> |
| 601 | Elf_Word |
| 602 | Elf_file<size, big_endian, File>::section_type(unsigned int shndx) |
| 603 | { |
| 604 | File* const file = this->file_; |
| 605 | |
| 606 | if (shndx >= this->shnum()) |
| 607 | file->error(_("section_type: bad shndx %u >= %u"), |
| 608 | shndx, this->shnum()); |
| 609 | |
| 610 | typename File::View v(file->view(this->section_header_offset(shndx), |
| 611 | This::shdr_size)); |
| 612 | |
| 613 | Ef_shdr shdr(v.data()); |
| 614 | return shdr.get_sh_type(); |
| 615 | } |
| 616 | |
| 617 | // Return the sh_link field of section SHNDX. |
| 618 | |
| 619 | template<int size, bool big_endian, typename File> |
| 620 | Elf_Word |
| 621 | Elf_file<size, big_endian, File>::section_link(unsigned int shndx) |
| 622 | { |
| 623 | File* const file = this->file_; |
| 624 | |
| 625 | if (shndx >= this->shnum()) |
| 626 | file->error(_("section_link: bad shndx %u >= %u"), |
| 627 | shndx, this->shnum()); |
| 628 | |
| 629 | typename File::View v(file->view(this->section_header_offset(shndx), |
| 630 | This::shdr_size)); |
| 631 | |
| 632 | Ef_shdr shdr(v.data()); |
| 633 | return shdr.get_sh_link(); |
| 634 | } |
| 635 | |
| 636 | // Return the sh_info field of section SHNDX. |
| 637 | |
| 638 | template<int size, bool big_endian, typename File> |
| 639 | Elf_Word |
| 640 | Elf_file<size, big_endian, File>::section_info(unsigned int shndx) |
| 641 | { |
| 642 | File* const file = this->file_; |
| 643 | |
| 644 | if (shndx >= this->shnum()) |
| 645 | file->error(_("section_info: bad shndx %u >= %u"), |
| 646 | shndx, this->shnum()); |
| 647 | |
| 648 | typename File::View v(file->view(this->section_header_offset(shndx), |
| 649 | This::shdr_size)); |
| 650 | |
| 651 | Ef_shdr shdr(v.data()); |
| 652 | return shdr.get_sh_info(); |
| 653 | } |
| 654 | |
| 655 | // Return the sh_addralign field of section SHNDX. |
| 656 | |
| 657 | template<int size, bool big_endian, typename File> |
| 658 | typename Elf_types<size>::Elf_WXword |
| 659 | Elf_file<size, big_endian, File>::section_addralign(unsigned int shndx) |
| 660 | { |
| 661 | File* const file = this->file_; |
| 662 | |
| 663 | if (shndx >= this->shnum()) |
| 664 | file->error(_("section_addralign: bad shndx %u >= %u"), |
| 665 | shndx, this->shnum()); |
| 666 | |
| 667 | typename File::View v(file->view(this->section_header_offset(shndx), |
| 668 | This::shdr_size)); |
| 669 | |
| 670 | Ef_shdr shdr(v.data()); |
| 671 | return shdr.get_sh_addralign(); |
| 672 | } |
| 673 | |
| 674 | inline |
| 675 | Elf_strtab::Elf_strtab(const unsigned char* p, size_t size) |
| 676 | { |
| 677 | // Check if the section is NUL-terminated. If it isn't, we ignore |
| 678 | // the last part to make sure we don't return non-NUL-terminated |
| 679 | // strings. |
| 680 | while (size > 0 && p[size - 1] != 0) |
| 681 | size--; |
| 682 | this->base_ = reinterpret_cast<const char*>(p); |
| 683 | this->usable_size_ = size; |
| 684 | } |
| 685 | |
| 686 | } // End namespace elfcpp. |
| 687 | |
| 688 | #endif // !defined(ELFCPP_FILE_H) |