| 1 | use alloc::vec::Vec; |
| 2 | use core::convert::TryInto; |
| 3 | use core::fmt::Debug; |
| 4 | use core::mem; |
| 5 | |
| 6 | use crate::elf; |
| 7 | use crate::endian::{self, Endian, Endianness, U32}; |
| 8 | use crate::pod::Pod; |
| 9 | use crate::read::{ |
| 10 | self, util, Architecture, ByteString, Bytes, Error, Export, FileFlags, Import, Object, |
| 11 | ObjectKind, ReadError, ReadRef, SectionIndex, StringTable, SymbolIndex, |
| 12 | }; |
| 13 | |
| 14 | use super::{ |
| 15 | CompressionHeader, Dyn, ElfComdat, ElfComdatIterator, ElfDynamicRelocationIterator, ElfSection, |
| 16 | ElfSectionIterator, ElfSegment, ElfSegmentIterator, ElfSymbol, ElfSymbolIterator, |
| 17 | ElfSymbolTable, NoteHeader, ProgramHeader, Rel, Rela, RelocationSections, Relr, SectionHeader, |
| 18 | SectionTable, Sym, SymbolTable, |
| 19 | }; |
| 20 | |
| 21 | /// A 32-bit ELF object file. |
| 22 | /// |
| 23 | /// This is a file that starts with [`elf::FileHeader32`], and corresponds |
| 24 | /// to [`crate::FileKind::Elf32`]. |
| 25 | pub type ElfFile32<'data, Endian = Endianness, R = &'data [u8]> = |
| 26 | ElfFile<'data, elf::FileHeader32<Endian>, R>; |
| 27 | /// A 64-bit ELF object file. |
| 28 | /// |
| 29 | /// This is a file that starts with [`elf::FileHeader64`], and corresponds |
| 30 | /// to [`crate::FileKind::Elf64`]. |
| 31 | pub type ElfFile64<'data, Endian = Endianness, R = &'data [u8]> = |
| 32 | ElfFile<'data, elf::FileHeader64<Endian>, R>; |
| 33 | |
| 34 | /// A partially parsed ELF file. |
| 35 | /// |
| 36 | /// Most functionality is provided by the [`Object`] trait implementation. |
| 37 | #[derive (Debug)] |
| 38 | pub struct ElfFile<'data, Elf, R = &'data [u8]> |
| 39 | where |
| 40 | Elf: FileHeader, |
| 41 | R: ReadRef<'data>, |
| 42 | { |
| 43 | pub(super) endian: Elf::Endian, |
| 44 | pub(super) data: R, |
| 45 | pub(super) header: &'data Elf, |
| 46 | pub(super) segments: &'data [Elf::ProgramHeader], |
| 47 | pub(super) sections: SectionTable<'data, Elf, R>, |
| 48 | pub(super) relocations: RelocationSections, |
| 49 | pub(super) symbols: SymbolTable<'data, Elf, R>, |
| 50 | pub(super) dynamic_symbols: SymbolTable<'data, Elf, R>, |
| 51 | } |
| 52 | |
| 53 | impl<'data, Elf, R> ElfFile<'data, Elf, R> |
| 54 | where |
| 55 | Elf: FileHeader, |
| 56 | R: ReadRef<'data>, |
| 57 | { |
| 58 | /// Parse the raw ELF file data. |
| 59 | pub fn parse(data: R) -> read::Result<Self> { |
| 60 | let header = Elf::parse(data)?; |
| 61 | let endian = header.endian()?; |
| 62 | let segments = header.program_headers(endian, data)?; |
| 63 | let sections = header.sections(endian, data)?; |
| 64 | let symbols = sections.symbols(endian, data, elf::SHT_SYMTAB)?; |
| 65 | // TODO: get dynamic symbols from DT_SYMTAB if there are no sections |
| 66 | let dynamic_symbols = sections.symbols(endian, data, elf::SHT_DYNSYM)?; |
| 67 | // The API we provide requires a mapping from section to relocations, so build it now. |
| 68 | let relocations = sections.relocation_sections(endian, symbols.section())?; |
| 69 | |
| 70 | Ok(ElfFile { |
| 71 | endian, |
| 72 | data, |
| 73 | header, |
| 74 | segments, |
| 75 | sections, |
| 76 | relocations, |
| 77 | symbols, |
| 78 | dynamic_symbols, |
| 79 | }) |
| 80 | } |
| 81 | |
| 82 | /// Returns the endianness. |
| 83 | pub fn endian(&self) -> Elf::Endian { |
| 84 | self.endian |
| 85 | } |
| 86 | |
| 87 | /// Returns the raw data. |
| 88 | pub fn data(&self) -> R { |
| 89 | self.data |
| 90 | } |
| 91 | |
| 92 | /// Returns the raw ELF file header. |
| 93 | #[deprecated (note = "Use `elf_header` instead" )] |
| 94 | pub fn raw_header(&self) -> &'data Elf { |
| 95 | self.header |
| 96 | } |
| 97 | |
| 98 | /// Returns the raw ELF segments. |
| 99 | #[deprecated (note = "Use `elf_program_headers` instead" )] |
| 100 | pub fn raw_segments(&self) -> &'data [Elf::ProgramHeader] { |
| 101 | self.segments |
| 102 | } |
| 103 | |
| 104 | /// Get the raw ELF file header. |
| 105 | pub fn elf_header(&self) -> &'data Elf { |
| 106 | self.header |
| 107 | } |
| 108 | |
| 109 | /// Get the raw ELF program headers. |
| 110 | /// |
| 111 | /// Returns an empty slice if the file has no program headers. |
| 112 | pub fn elf_program_headers(&self) -> &'data [Elf::ProgramHeader] { |
| 113 | self.segments |
| 114 | } |
| 115 | |
| 116 | /// Get the ELF section table. |
| 117 | /// |
| 118 | /// Returns an empty section table if the file has no section headers. |
| 119 | pub fn elf_section_table(&self) -> &SectionTable<'data, Elf, R> { |
| 120 | &self.sections |
| 121 | } |
| 122 | |
| 123 | /// Get the ELF symbol table. |
| 124 | /// |
| 125 | /// Returns an empty symbol table if the file has no symbol table. |
| 126 | pub fn elf_symbol_table(&self) -> &SymbolTable<'data, Elf, R> { |
| 127 | &self.symbols |
| 128 | } |
| 129 | |
| 130 | /// Get the ELF dynamic symbol table. |
| 131 | /// |
| 132 | /// Returns an empty symbol table if the file has no dynamic symbol table. |
| 133 | pub fn elf_dynamic_symbol_table(&self) -> &SymbolTable<'data, Elf, R> { |
| 134 | &self.dynamic_symbols |
| 135 | } |
| 136 | |
| 137 | /// Get a mapping for linked relocation sections. |
| 138 | pub fn elf_relocation_sections(&self) -> &RelocationSections { |
| 139 | &self.relocations |
| 140 | } |
| 141 | |
| 142 | fn raw_section_by_name<'file>( |
| 143 | &'file self, |
| 144 | section_name: &[u8], |
| 145 | ) -> Option<ElfSection<'data, 'file, Elf, R>> { |
| 146 | self.sections |
| 147 | .section_by_name(self.endian, section_name) |
| 148 | .map(|(index, section)| ElfSection { |
| 149 | file: self, |
| 150 | index, |
| 151 | section, |
| 152 | }) |
| 153 | } |
| 154 | |
| 155 | #[cfg (feature = "compression" )] |
| 156 | fn zdebug_section_by_name<'file>( |
| 157 | &'file self, |
| 158 | section_name: &[u8], |
| 159 | ) -> Option<ElfSection<'data, 'file, Elf, R>> { |
| 160 | if !section_name.starts_with(b".debug_" ) { |
| 161 | return None; |
| 162 | } |
| 163 | let mut name = Vec::with_capacity(section_name.len() + 1); |
| 164 | name.extend_from_slice(b".zdebug_" ); |
| 165 | name.extend_from_slice(§ion_name[7..]); |
| 166 | self.raw_section_by_name(&name) |
| 167 | } |
| 168 | |
| 169 | #[cfg (not(feature = "compression" ))] |
| 170 | fn zdebug_section_by_name<'file>( |
| 171 | &'file self, |
| 172 | _section_name: &[u8], |
| 173 | ) -> Option<ElfSection<'data, 'file, Elf, R>> { |
| 174 | None |
| 175 | } |
| 176 | } |
| 177 | |
| 178 | impl<'data, Elf, R> read::private::Sealed for ElfFile<'data, Elf, R> |
| 179 | where |
| 180 | Elf: FileHeader, |
| 181 | R: ReadRef<'data>, |
| 182 | { |
| 183 | } |
| 184 | |
| 185 | impl<'data, Elf, R> Object<'data> for ElfFile<'data, Elf, R> |
| 186 | where |
| 187 | Elf: FileHeader, |
| 188 | R: ReadRef<'data>, |
| 189 | { |
| 190 | type Segment<'file> |
| 191 | = ElfSegment<'data, 'file, Elf, R> |
| 192 | where |
| 193 | Self: 'file, |
| 194 | 'data: 'file; |
| 195 | type SegmentIterator<'file> |
| 196 | = ElfSegmentIterator<'data, 'file, Elf, R> |
| 197 | where |
| 198 | Self: 'file, |
| 199 | 'data: 'file; |
| 200 | type Section<'file> |
| 201 | = ElfSection<'data, 'file, Elf, R> |
| 202 | where |
| 203 | Self: 'file, |
| 204 | 'data: 'file; |
| 205 | type SectionIterator<'file> |
| 206 | = ElfSectionIterator<'data, 'file, Elf, R> |
| 207 | where |
| 208 | Self: 'file, |
| 209 | 'data: 'file; |
| 210 | type Comdat<'file> |
| 211 | = ElfComdat<'data, 'file, Elf, R> |
| 212 | where |
| 213 | Self: 'file, |
| 214 | 'data: 'file; |
| 215 | type ComdatIterator<'file> |
| 216 | = ElfComdatIterator<'data, 'file, Elf, R> |
| 217 | where |
| 218 | Self: 'file, |
| 219 | 'data: 'file; |
| 220 | type Symbol<'file> |
| 221 | = ElfSymbol<'data, 'file, Elf, R> |
| 222 | where |
| 223 | Self: 'file, |
| 224 | 'data: 'file; |
| 225 | type SymbolIterator<'file> |
| 226 | = ElfSymbolIterator<'data, 'file, Elf, R> |
| 227 | where |
| 228 | Self: 'file, |
| 229 | 'data: 'file; |
| 230 | type SymbolTable<'file> |
| 231 | = ElfSymbolTable<'data, 'file, Elf, R> |
| 232 | where |
| 233 | Self: 'file, |
| 234 | 'data: 'file; |
| 235 | type DynamicRelocationIterator<'file> |
| 236 | = ElfDynamicRelocationIterator<'data, 'file, Elf, R> |
| 237 | where |
| 238 | Self: 'file, |
| 239 | 'data: 'file; |
| 240 | |
| 241 | fn architecture(&self) -> Architecture { |
| 242 | match ( |
| 243 | self.header.e_machine(self.endian), |
| 244 | self.header.is_class_64(), |
| 245 | ) { |
| 246 | (elf::EM_AARCH64, true) => Architecture::Aarch64, |
| 247 | (elf::EM_AARCH64, false) => Architecture::Aarch64_Ilp32, |
| 248 | (elf::EM_ARM, _) => Architecture::Arm, |
| 249 | (elf::EM_AVR, _) => Architecture::Avr, |
| 250 | (elf::EM_BPF, _) => Architecture::Bpf, |
| 251 | (elf::EM_CSKY, _) => Architecture::Csky, |
| 252 | (elf::EM_MCST_ELBRUS, false) => Architecture::E2K32, |
| 253 | (elf::EM_MCST_ELBRUS, true) => Architecture::E2K64, |
| 254 | (elf::EM_386, _) => Architecture::I386, |
| 255 | (elf::EM_X86_64, false) => Architecture::X86_64_X32, |
| 256 | (elf::EM_X86_64, true) => Architecture::X86_64, |
| 257 | (elf::EM_HEXAGON, _) => Architecture::Hexagon, |
| 258 | (elf::EM_LOONGARCH, true) => Architecture::LoongArch64, |
| 259 | (elf::EM_68K, false) => Architecture::M68k, |
| 260 | (elf::EM_MIPS, false) => { |
| 261 | if (self.header.e_flags(self.endian) & elf::EF_MIPS_ABI2) != 0 { |
| 262 | Architecture::Mips64_N32 |
| 263 | } else { |
| 264 | Architecture::Mips |
| 265 | } |
| 266 | } |
| 267 | (elf::EM_MIPS, true) => Architecture::Mips64, |
| 268 | (elf::EM_MSP430, _) => Architecture::Msp430, |
| 269 | (elf::EM_PPC, _) => Architecture::PowerPc, |
| 270 | (elf::EM_PPC64, _) => Architecture::PowerPc64, |
| 271 | (elf::EM_RISCV, false) => Architecture::Riscv32, |
| 272 | (elf::EM_RISCV, true) => Architecture::Riscv64, |
| 273 | // This is either s390 or s390x, depending on the ELF class. |
| 274 | // We only support the 64-bit variant s390x here. |
| 275 | (elf::EM_S390, true) => Architecture::S390x, |
| 276 | (elf::EM_SBF, _) => Architecture::Sbf, |
| 277 | (elf::EM_SHARC, false) => Architecture::Sharc, |
| 278 | (elf::EM_SPARC, false) => Architecture::Sparc, |
| 279 | (elf::EM_SPARC32PLUS, false) => Architecture::Sparc32Plus, |
| 280 | (elf::EM_SPARCV9, true) => Architecture::Sparc64, |
| 281 | (elf::EM_XTENSA, false) => Architecture::Xtensa, |
| 282 | _ => Architecture::Unknown, |
| 283 | } |
| 284 | } |
| 285 | |
| 286 | #[inline ] |
| 287 | fn is_little_endian(&self) -> bool { |
| 288 | self.header.is_little_endian() |
| 289 | } |
| 290 | |
| 291 | #[inline ] |
| 292 | fn is_64(&self) -> bool { |
| 293 | self.header.is_class_64() |
| 294 | } |
| 295 | |
| 296 | fn kind(&self) -> ObjectKind { |
| 297 | match self.header.e_type(self.endian) { |
| 298 | elf::ET_REL => ObjectKind::Relocatable, |
| 299 | elf::ET_EXEC => ObjectKind::Executable, |
| 300 | // TODO: check for `DF_1_PIE`? |
| 301 | elf::ET_DYN => ObjectKind::Dynamic, |
| 302 | elf::ET_CORE => ObjectKind::Core, |
| 303 | _ => ObjectKind::Unknown, |
| 304 | } |
| 305 | } |
| 306 | |
| 307 | fn segments(&self) -> ElfSegmentIterator<'data, '_, Elf, R> { |
| 308 | ElfSegmentIterator { |
| 309 | file: self, |
| 310 | iter: self.segments.iter(), |
| 311 | } |
| 312 | } |
| 313 | |
| 314 | fn section_by_name_bytes<'file>( |
| 315 | &'file self, |
| 316 | section_name: &[u8], |
| 317 | ) -> Option<ElfSection<'data, 'file, Elf, R>> { |
| 318 | self.raw_section_by_name(section_name) |
| 319 | .or_else(|| self.zdebug_section_by_name(section_name)) |
| 320 | } |
| 321 | |
| 322 | fn section_by_index(&self, index: SectionIndex) -> read::Result<ElfSection<'data, '_, Elf, R>> { |
| 323 | let section = self.sections.section(index)?; |
| 324 | Ok(ElfSection { |
| 325 | file: self, |
| 326 | index, |
| 327 | section, |
| 328 | }) |
| 329 | } |
| 330 | |
| 331 | fn sections(&self) -> ElfSectionIterator<'data, '_, Elf, R> { |
| 332 | ElfSectionIterator::new(self) |
| 333 | } |
| 334 | |
| 335 | fn comdats(&self) -> ElfComdatIterator<'data, '_, Elf, R> { |
| 336 | ElfComdatIterator::new(self) |
| 337 | } |
| 338 | |
| 339 | fn symbol_by_index(&self, index: SymbolIndex) -> read::Result<ElfSymbol<'data, '_, Elf, R>> { |
| 340 | let symbol = self.symbols.symbol(index)?; |
| 341 | Ok(ElfSymbol { |
| 342 | endian: self.endian, |
| 343 | symbols: &self.symbols, |
| 344 | index, |
| 345 | symbol, |
| 346 | }) |
| 347 | } |
| 348 | |
| 349 | fn symbols(&self) -> ElfSymbolIterator<'data, '_, Elf, R> { |
| 350 | ElfSymbolIterator::new(self.endian, &self.symbols) |
| 351 | } |
| 352 | |
| 353 | fn symbol_table(&self) -> Option<ElfSymbolTable<'data, '_, Elf, R>> { |
| 354 | if self.symbols.is_empty() { |
| 355 | return None; |
| 356 | } |
| 357 | Some(ElfSymbolTable { |
| 358 | endian: self.endian, |
| 359 | symbols: &self.symbols, |
| 360 | }) |
| 361 | } |
| 362 | |
| 363 | fn dynamic_symbols(&self) -> ElfSymbolIterator<'data, '_, Elf, R> { |
| 364 | ElfSymbolIterator::new(self.endian, &self.dynamic_symbols) |
| 365 | } |
| 366 | |
| 367 | fn dynamic_symbol_table(&self) -> Option<ElfSymbolTable<'data, '_, Elf, R>> { |
| 368 | if self.dynamic_symbols.is_empty() { |
| 369 | return None; |
| 370 | } |
| 371 | Some(ElfSymbolTable { |
| 372 | endian: self.endian, |
| 373 | symbols: &self.dynamic_symbols, |
| 374 | }) |
| 375 | } |
| 376 | |
| 377 | fn dynamic_relocations<'file>( |
| 378 | &'file self, |
| 379 | ) -> Option<ElfDynamicRelocationIterator<'data, 'file, Elf, R>> { |
| 380 | Some(ElfDynamicRelocationIterator { |
| 381 | section_index: SectionIndex(1), |
| 382 | file: self, |
| 383 | relocations: None, |
| 384 | }) |
| 385 | } |
| 386 | |
| 387 | fn imports(&self) -> read::Result<Vec<Import<'data>>> { |
| 388 | let versions = self.sections.versions(self.endian, self.data)?; |
| 389 | |
| 390 | let mut imports = Vec::new(); |
| 391 | for (index, symbol) in self.dynamic_symbols.enumerate() { |
| 392 | if symbol.is_undefined(self.endian) { |
| 393 | let name = symbol.name(self.endian, self.dynamic_symbols.strings())?; |
| 394 | if !name.is_empty() { |
| 395 | let library = if let Some(svt) = versions.as_ref() { |
| 396 | let vi = svt.version_index(self.endian, index); |
| 397 | svt.version(vi)?.and_then(|v| v.file()) |
| 398 | } else { |
| 399 | None |
| 400 | } |
| 401 | .unwrap_or(&[]); |
| 402 | imports.push(Import { |
| 403 | name: ByteString(name), |
| 404 | library: ByteString(library), |
| 405 | }); |
| 406 | } |
| 407 | } |
| 408 | } |
| 409 | Ok(imports) |
| 410 | } |
| 411 | |
| 412 | fn exports(&self) -> read::Result<Vec<Export<'data>>> { |
| 413 | let mut exports = Vec::new(); |
| 414 | for symbol in self.dynamic_symbols.iter() { |
| 415 | if symbol.is_definition(self.endian) { |
| 416 | let name = symbol.name(self.endian, self.dynamic_symbols.strings())?; |
| 417 | let address = symbol.st_value(self.endian).into(); |
| 418 | exports.push(Export { |
| 419 | name: ByteString(name), |
| 420 | address, |
| 421 | }); |
| 422 | } |
| 423 | } |
| 424 | Ok(exports) |
| 425 | } |
| 426 | |
| 427 | fn has_debug_symbols(&self) -> bool { |
| 428 | for section in self.sections.iter() { |
| 429 | if let Ok(name) = self.sections.section_name(self.endian, section) { |
| 430 | if name == b".debug_info" || name == b".zdebug_info" { |
| 431 | return true; |
| 432 | } |
| 433 | } |
| 434 | } |
| 435 | false |
| 436 | } |
| 437 | |
| 438 | fn build_id(&self) -> read::Result<Option<&'data [u8]>> { |
| 439 | let endian = self.endian; |
| 440 | // Use section headers if present, otherwise use program headers. |
| 441 | if !self.sections.is_empty() { |
| 442 | for section in self.sections.iter() { |
| 443 | if let Some(mut notes) = section.notes(endian, self.data)? { |
| 444 | while let Some(note) = notes.next()? { |
| 445 | if note.name() == elf::ELF_NOTE_GNU |
| 446 | && note.n_type(endian) == elf::NT_GNU_BUILD_ID |
| 447 | { |
| 448 | return Ok(Some(note.desc())); |
| 449 | } |
| 450 | } |
| 451 | } |
| 452 | } |
| 453 | } else { |
| 454 | for segment in self.segments { |
| 455 | if let Some(mut notes) = segment.notes(endian, self.data)? { |
| 456 | while let Some(note) = notes.next()? { |
| 457 | if note.name() == elf::ELF_NOTE_GNU |
| 458 | && note.n_type(endian) == elf::NT_GNU_BUILD_ID |
| 459 | { |
| 460 | return Ok(Some(note.desc())); |
| 461 | } |
| 462 | } |
| 463 | } |
| 464 | } |
| 465 | } |
| 466 | Ok(None) |
| 467 | } |
| 468 | |
| 469 | fn gnu_debuglink(&self) -> read::Result<Option<(&'data [u8], u32)>> { |
| 470 | let section = match self.raw_section_by_name(b".gnu_debuglink" ) { |
| 471 | Some(section) => section, |
| 472 | None => return Ok(None), |
| 473 | }; |
| 474 | let data = section |
| 475 | .section |
| 476 | .data(self.endian, self.data) |
| 477 | .read_error("Invalid ELF .gnu_debuglink section offset or size" ) |
| 478 | .map(Bytes)?; |
| 479 | let filename = data |
| 480 | .read_string_at(0) |
| 481 | .read_error("Missing ELF .gnu_debuglink filename" )?; |
| 482 | let crc_offset = util::align(filename.len() + 1, 4); |
| 483 | let crc = data |
| 484 | .read_at::<U32<_>>(crc_offset) |
| 485 | .read_error("Missing ELF .gnu_debuglink crc" )? |
| 486 | .get(self.endian); |
| 487 | Ok(Some((filename, crc))) |
| 488 | } |
| 489 | |
| 490 | fn gnu_debugaltlink(&self) -> read::Result<Option<(&'data [u8], &'data [u8])>> { |
| 491 | let section = match self.raw_section_by_name(b".gnu_debugaltlink" ) { |
| 492 | Some(section) => section, |
| 493 | None => return Ok(None), |
| 494 | }; |
| 495 | let mut data = section |
| 496 | .section |
| 497 | .data(self.endian, self.data) |
| 498 | .read_error("Invalid ELF .gnu_debugaltlink section offset or size" ) |
| 499 | .map(Bytes)?; |
| 500 | let filename = data |
| 501 | .read_string() |
| 502 | .read_error("Missing ELF .gnu_debugaltlink filename" )?; |
| 503 | let build_id = data.0; |
| 504 | Ok(Some((filename, build_id))) |
| 505 | } |
| 506 | |
| 507 | fn relative_address_base(&self) -> u64 { |
| 508 | 0 |
| 509 | } |
| 510 | |
| 511 | fn entry(&self) -> u64 { |
| 512 | self.header.e_entry(self.endian).into() |
| 513 | } |
| 514 | |
| 515 | fn flags(&self) -> FileFlags { |
| 516 | FileFlags::Elf { |
| 517 | os_abi: self.header.e_ident().os_abi, |
| 518 | abi_version: self.header.e_ident().abi_version, |
| 519 | e_flags: self.header.e_flags(self.endian), |
| 520 | } |
| 521 | } |
| 522 | } |
| 523 | |
| 524 | /// A trait for generic access to [`elf::FileHeader32`] and [`elf::FileHeader64`]. |
| 525 | #[allow (missing_docs)] |
| 526 | pub trait FileHeader: Debug + Pod { |
| 527 | // Ideally this would be a `u64: From<Word>`, but can't express that. |
| 528 | type Word: Into<u64> + Default + Copy; |
| 529 | type Sword: Into<i64>; |
| 530 | type Endian: endian::Endian; |
| 531 | type ProgramHeader: ProgramHeader<Elf = Self, Endian = Self::Endian, Word = Self::Word>; |
| 532 | type SectionHeader: SectionHeader<Elf = Self, Endian = Self::Endian, Word = Self::Word>; |
| 533 | type CompressionHeader: CompressionHeader<Endian = Self::Endian, Word = Self::Word>; |
| 534 | type NoteHeader: NoteHeader<Endian = Self::Endian>; |
| 535 | type Dyn: Dyn<Endian = Self::Endian, Word = Self::Word>; |
| 536 | type Sym: Sym<Endian = Self::Endian, Word = Self::Word>; |
| 537 | type Rel: Rel<Endian = Self::Endian, Word = Self::Word>; |
| 538 | type Rela: Rela<Endian = Self::Endian, Word = Self::Word> + From<Self::Rel>; |
| 539 | type Relr: Relr<Endian = Self::Endian, Word = Self::Word>; |
| 540 | |
| 541 | /// Return true if this type is a 64-bit header. |
| 542 | /// |
| 543 | /// This is a property of the type, not a value in the header data. |
| 544 | fn is_type_64(&self) -> bool; |
| 545 | |
| 546 | /// Return true if this type is a 64-bit header. |
| 547 | /// |
| 548 | /// This is a property of the type, not a value in the header data. |
| 549 | /// |
| 550 | /// This is the same as [`Self::is_type_64`], but is non-dispatchable. |
| 551 | fn is_type_64_sized() -> bool |
| 552 | where |
| 553 | Self: Sized; |
| 554 | |
| 555 | fn e_ident(&self) -> &elf::Ident; |
| 556 | fn e_type(&self, endian: Self::Endian) -> u16; |
| 557 | fn e_machine(&self, endian: Self::Endian) -> u16; |
| 558 | fn e_version(&self, endian: Self::Endian) -> u32; |
| 559 | fn e_entry(&self, endian: Self::Endian) -> Self::Word; |
| 560 | fn e_phoff(&self, endian: Self::Endian) -> Self::Word; |
| 561 | fn e_shoff(&self, endian: Self::Endian) -> Self::Word; |
| 562 | fn e_flags(&self, endian: Self::Endian) -> u32; |
| 563 | fn e_ehsize(&self, endian: Self::Endian) -> u16; |
| 564 | fn e_phentsize(&self, endian: Self::Endian) -> u16; |
| 565 | fn e_phnum(&self, endian: Self::Endian) -> u16; |
| 566 | fn e_shentsize(&self, endian: Self::Endian) -> u16; |
| 567 | fn e_shnum(&self, endian: Self::Endian) -> u16; |
| 568 | fn e_shstrndx(&self, endian: Self::Endian) -> u16; |
| 569 | |
| 570 | // Provided methods. |
| 571 | |
| 572 | /// Read the file header. |
| 573 | /// |
| 574 | /// Also checks that the ident field in the file header is a supported format. |
| 575 | fn parse<'data, R: ReadRef<'data>>(data: R) -> read::Result<&'data Self> { |
| 576 | let header = data |
| 577 | .read_at::<Self>(0) |
| 578 | .read_error("Invalid ELF header size or alignment" )?; |
| 579 | if !header.is_supported() { |
| 580 | return Err(Error("Unsupported ELF header" )); |
| 581 | } |
| 582 | // TODO: Check self.e_ehsize? |
| 583 | Ok(header) |
| 584 | } |
| 585 | |
| 586 | /// Check that the ident field in the file header is a supported format. |
| 587 | /// |
| 588 | /// This checks the magic number, version, class, and endianness. |
| 589 | fn is_supported(&self) -> bool { |
| 590 | let ident = self.e_ident(); |
| 591 | // TODO: Check self.e_version too? Requires endian though. |
| 592 | ident.magic == elf::ELFMAG |
| 593 | && (self.is_type_64() || self.is_class_32()) |
| 594 | && (!self.is_type_64() || self.is_class_64()) |
| 595 | && (self.is_little_endian() || self.is_big_endian()) |
| 596 | && ident.version == elf::EV_CURRENT |
| 597 | } |
| 598 | |
| 599 | fn is_class_32(&self) -> bool { |
| 600 | self.e_ident().class == elf::ELFCLASS32 |
| 601 | } |
| 602 | |
| 603 | fn is_class_64(&self) -> bool { |
| 604 | self.e_ident().class == elf::ELFCLASS64 |
| 605 | } |
| 606 | |
| 607 | fn is_little_endian(&self) -> bool { |
| 608 | self.e_ident().data == elf::ELFDATA2LSB |
| 609 | } |
| 610 | |
| 611 | fn is_big_endian(&self) -> bool { |
| 612 | self.e_ident().data == elf::ELFDATA2MSB |
| 613 | } |
| 614 | |
| 615 | fn endian(&self) -> read::Result<Self::Endian> { |
| 616 | Self::Endian::from_big_endian(self.is_big_endian()).read_error("Unsupported ELF endian" ) |
| 617 | } |
| 618 | |
| 619 | /// Return the first section header, if present. |
| 620 | /// |
| 621 | /// Section 0 is a special case because getting the section headers normally |
| 622 | /// requires `shnum`, but `shnum` may be in the first section header. |
| 623 | fn section_0<'data, R: ReadRef<'data>>( |
| 624 | &self, |
| 625 | endian: Self::Endian, |
| 626 | data: R, |
| 627 | ) -> read::Result<Option<&'data Self::SectionHeader>> { |
| 628 | let shoff: u64 = self.e_shoff(endian).into(); |
| 629 | if shoff == 0 { |
| 630 | // No section headers is ok. |
| 631 | return Ok(None); |
| 632 | } |
| 633 | let shentsize = usize::from(self.e_shentsize(endian)); |
| 634 | if shentsize != mem::size_of::<Self::SectionHeader>() { |
| 635 | // Section header size must match. |
| 636 | return Err(Error("Invalid ELF section header entry size" )); |
| 637 | } |
| 638 | data.read_at(shoff) |
| 639 | .map(Some) |
| 640 | .read_error("Invalid ELF section header offset or size" ) |
| 641 | } |
| 642 | |
| 643 | /// Return the `e_phnum` field of the header. Handles extended values. |
| 644 | /// |
| 645 | /// Returns `Err` for invalid values. |
| 646 | fn phnum<'data, R: ReadRef<'data>>( |
| 647 | &self, |
| 648 | endian: Self::Endian, |
| 649 | data: R, |
| 650 | ) -> read::Result<usize> { |
| 651 | let e_phnum = self.e_phnum(endian); |
| 652 | if e_phnum < elf::PN_XNUM { |
| 653 | Ok(e_phnum as usize) |
| 654 | } else if let Some(section_0) = self.section_0(endian, data)? { |
| 655 | Ok(section_0.sh_info(endian) as usize) |
| 656 | } else { |
| 657 | // Section 0 must exist if e_phnum overflows. |
| 658 | Err(Error("Missing ELF section headers for e_phnum overflow" )) |
| 659 | } |
| 660 | } |
| 661 | |
| 662 | /// Return the `e_shnum` field of the header. Handles extended values. |
| 663 | /// |
| 664 | /// Returns `Err` for invalid values. |
| 665 | fn shnum<'data, R: ReadRef<'data>>( |
| 666 | &self, |
| 667 | endian: Self::Endian, |
| 668 | data: R, |
| 669 | ) -> read::Result<usize> { |
| 670 | let e_shnum = self.e_shnum(endian); |
| 671 | if e_shnum > 0 { |
| 672 | Ok(e_shnum as usize) |
| 673 | } else if let Some(section_0) = self.section_0(endian, data)? { |
| 674 | section_0 |
| 675 | .sh_size(endian) |
| 676 | .into() |
| 677 | .try_into() |
| 678 | .ok() |
| 679 | .read_error("Invalid ELF extended e_shnum" ) |
| 680 | } else { |
| 681 | // No section headers is ok. |
| 682 | Ok(0) |
| 683 | } |
| 684 | } |
| 685 | |
| 686 | /// Return the `e_shstrndx` field of the header. Handles extended values. |
| 687 | /// |
| 688 | /// Returns `Err` for invalid values (including if the index is 0). |
| 689 | fn shstrndx<'data, R: ReadRef<'data>>( |
| 690 | &self, |
| 691 | endian: Self::Endian, |
| 692 | data: R, |
| 693 | ) -> read::Result<u32> { |
| 694 | let e_shstrndx = self.e_shstrndx(endian); |
| 695 | let index = if e_shstrndx != elf::SHN_XINDEX { |
| 696 | e_shstrndx.into() |
| 697 | } else if let Some(section_0) = self.section_0(endian, data)? { |
| 698 | section_0.sh_link(endian) |
| 699 | } else { |
| 700 | // Section 0 must exist if we're trying to read e_shstrndx. |
| 701 | return Err(Error("Missing ELF section headers for e_shstrndx overflow" )); |
| 702 | }; |
| 703 | if index == 0 { |
| 704 | return Err(Error("Missing ELF e_shstrndx" )); |
| 705 | } |
| 706 | Ok(index) |
| 707 | } |
| 708 | |
| 709 | /// Return the slice of program headers. |
| 710 | /// |
| 711 | /// Returns `Ok(&[])` if there are no program headers. |
| 712 | /// Returns `Err` for invalid values. |
| 713 | fn program_headers<'data, R: ReadRef<'data>>( |
| 714 | &self, |
| 715 | endian: Self::Endian, |
| 716 | data: R, |
| 717 | ) -> read::Result<&'data [Self::ProgramHeader]> { |
| 718 | let phoff: u64 = self.e_phoff(endian).into(); |
| 719 | if phoff == 0 { |
| 720 | // No program headers is ok. |
| 721 | return Ok(&[]); |
| 722 | } |
| 723 | let phnum = self.phnum(endian, data)?; |
| 724 | if phnum == 0 { |
| 725 | // No program headers is ok. |
| 726 | return Ok(&[]); |
| 727 | } |
| 728 | let phentsize = self.e_phentsize(endian) as usize; |
| 729 | if phentsize != mem::size_of::<Self::ProgramHeader>() { |
| 730 | // Program header size must match. |
| 731 | return Err(Error("Invalid ELF program header entry size" )); |
| 732 | } |
| 733 | data.read_slice_at(phoff, phnum) |
| 734 | .read_error("Invalid ELF program header size or alignment" ) |
| 735 | } |
| 736 | |
| 737 | /// Return the slice of section headers. |
| 738 | /// |
| 739 | /// Returns `Ok(&[])` if there are no section headers. |
| 740 | /// Returns `Err` for invalid values. |
| 741 | fn section_headers<'data, R: ReadRef<'data>>( |
| 742 | &self, |
| 743 | endian: Self::Endian, |
| 744 | data: R, |
| 745 | ) -> read::Result<&'data [Self::SectionHeader]> { |
| 746 | let shoff: u64 = self.e_shoff(endian).into(); |
| 747 | if shoff == 0 { |
| 748 | // No section headers is ok. |
| 749 | return Ok(&[]); |
| 750 | } |
| 751 | let shnum = self.shnum(endian, data)?; |
| 752 | if shnum == 0 { |
| 753 | // No section headers is ok. |
| 754 | return Ok(&[]); |
| 755 | } |
| 756 | let shentsize = usize::from(self.e_shentsize(endian)); |
| 757 | if shentsize != mem::size_of::<Self::SectionHeader>() { |
| 758 | // Section header size must match. |
| 759 | return Err(Error("Invalid ELF section header entry size" )); |
| 760 | } |
| 761 | data.read_slice_at(shoff, shnum) |
| 762 | .read_error("Invalid ELF section header offset/size/alignment" ) |
| 763 | } |
| 764 | |
| 765 | /// Get the section index of the section header string table. |
| 766 | /// |
| 767 | /// Returns `Err` for invalid values (including if the index is 0). |
| 768 | fn section_strings_index<'data, R: ReadRef<'data>>( |
| 769 | &self, |
| 770 | endian: Self::Endian, |
| 771 | data: R, |
| 772 | ) -> read::Result<SectionIndex> { |
| 773 | self.shstrndx(endian, data) |
| 774 | .map(|index| SectionIndex(index as usize)) |
| 775 | } |
| 776 | |
| 777 | /// Return the string table for the section headers. |
| 778 | fn section_strings<'data, R: ReadRef<'data>>( |
| 779 | &self, |
| 780 | endian: Self::Endian, |
| 781 | data: R, |
| 782 | sections: &[Self::SectionHeader], |
| 783 | ) -> read::Result<StringTable<'data, R>> { |
| 784 | if sections.is_empty() { |
| 785 | return Ok(StringTable::default()); |
| 786 | } |
| 787 | let index = self.section_strings_index(endian, data)?; |
| 788 | let shstrtab = sections.get(index.0).read_error("Invalid ELF e_shstrndx" )?; |
| 789 | let strings = if let Some((shstrtab_offset, shstrtab_size)) = shstrtab.file_range(endian) { |
| 790 | let shstrtab_end = shstrtab_offset |
| 791 | .checked_add(shstrtab_size) |
| 792 | .read_error("Invalid ELF shstrtab size" )?; |
| 793 | StringTable::new(data, shstrtab_offset, shstrtab_end) |
| 794 | } else { |
| 795 | StringTable::default() |
| 796 | }; |
| 797 | Ok(strings) |
| 798 | } |
| 799 | |
| 800 | /// Return the section table. |
| 801 | fn sections<'data, R: ReadRef<'data>>( |
| 802 | &self, |
| 803 | endian: Self::Endian, |
| 804 | data: R, |
| 805 | ) -> read::Result<SectionTable<'data, Self, R>> { |
| 806 | let sections = self.section_headers(endian, data)?; |
| 807 | let strings = self.section_strings(endian, data, sections)?; |
| 808 | Ok(SectionTable::new(sections, strings)) |
| 809 | } |
| 810 | |
| 811 | /// Returns whether this is a mips64el elf file. |
| 812 | fn is_mips64el(&self, endian: Self::Endian) -> bool { |
| 813 | self.is_class_64() && self.is_little_endian() && self.e_machine(endian) == elf::EM_MIPS |
| 814 | } |
| 815 | } |
| 816 | |
| 817 | impl<Endian: endian::Endian> FileHeader for elf::FileHeader32<Endian> { |
| 818 | type Word = u32; |
| 819 | type Sword = i32; |
| 820 | type Endian = Endian; |
| 821 | type ProgramHeader = elf::ProgramHeader32<Endian>; |
| 822 | type SectionHeader = elf::SectionHeader32<Endian>; |
| 823 | type CompressionHeader = elf::CompressionHeader32<Endian>; |
| 824 | type NoteHeader = elf::NoteHeader32<Endian>; |
| 825 | type Dyn = elf::Dyn32<Endian>; |
| 826 | type Sym = elf::Sym32<Endian>; |
| 827 | type Rel = elf::Rel32<Endian>; |
| 828 | type Rela = elf::Rela32<Endian>; |
| 829 | type Relr = elf::Relr32<Endian>; |
| 830 | |
| 831 | #[inline ] |
| 832 | fn is_type_64(&self) -> bool { |
| 833 | false |
| 834 | } |
| 835 | |
| 836 | #[inline ] |
| 837 | fn is_type_64_sized() -> bool |
| 838 | where |
| 839 | Self: Sized, |
| 840 | { |
| 841 | false |
| 842 | } |
| 843 | |
| 844 | #[inline ] |
| 845 | fn e_ident(&self) -> &elf::Ident { |
| 846 | &self.e_ident |
| 847 | } |
| 848 | |
| 849 | #[inline ] |
| 850 | fn e_type(&self, endian: Self::Endian) -> u16 { |
| 851 | self.e_type.get(endian) |
| 852 | } |
| 853 | |
| 854 | #[inline ] |
| 855 | fn e_machine(&self, endian: Self::Endian) -> u16 { |
| 856 | self.e_machine.get(endian) |
| 857 | } |
| 858 | |
| 859 | #[inline ] |
| 860 | fn e_version(&self, endian: Self::Endian) -> u32 { |
| 861 | self.e_version.get(endian) |
| 862 | } |
| 863 | |
| 864 | #[inline ] |
| 865 | fn e_entry(&self, endian: Self::Endian) -> Self::Word { |
| 866 | self.e_entry.get(endian) |
| 867 | } |
| 868 | |
| 869 | #[inline ] |
| 870 | fn e_phoff(&self, endian: Self::Endian) -> Self::Word { |
| 871 | self.e_phoff.get(endian) |
| 872 | } |
| 873 | |
| 874 | #[inline ] |
| 875 | fn e_shoff(&self, endian: Self::Endian) -> Self::Word { |
| 876 | self.e_shoff.get(endian) |
| 877 | } |
| 878 | |
| 879 | #[inline ] |
| 880 | fn e_flags(&self, endian: Self::Endian) -> u32 { |
| 881 | self.e_flags.get(endian) |
| 882 | } |
| 883 | |
| 884 | #[inline ] |
| 885 | fn e_ehsize(&self, endian: Self::Endian) -> u16 { |
| 886 | self.e_ehsize.get(endian) |
| 887 | } |
| 888 | |
| 889 | #[inline ] |
| 890 | fn e_phentsize(&self, endian: Self::Endian) -> u16 { |
| 891 | self.e_phentsize.get(endian) |
| 892 | } |
| 893 | |
| 894 | #[inline ] |
| 895 | fn e_phnum(&self, endian: Self::Endian) -> u16 { |
| 896 | self.e_phnum.get(endian) |
| 897 | } |
| 898 | |
| 899 | #[inline ] |
| 900 | fn e_shentsize(&self, endian: Self::Endian) -> u16 { |
| 901 | self.e_shentsize.get(endian) |
| 902 | } |
| 903 | |
| 904 | #[inline ] |
| 905 | fn e_shnum(&self, endian: Self::Endian) -> u16 { |
| 906 | self.e_shnum.get(endian) |
| 907 | } |
| 908 | |
| 909 | #[inline ] |
| 910 | fn e_shstrndx(&self, endian: Self::Endian) -> u16 { |
| 911 | self.e_shstrndx.get(endian) |
| 912 | } |
| 913 | } |
| 914 | |
| 915 | impl<Endian: endian::Endian> FileHeader for elf::FileHeader64<Endian> { |
| 916 | type Word = u64; |
| 917 | type Sword = i64; |
| 918 | type Endian = Endian; |
| 919 | type ProgramHeader = elf::ProgramHeader64<Endian>; |
| 920 | type SectionHeader = elf::SectionHeader64<Endian>; |
| 921 | type CompressionHeader = elf::CompressionHeader64<Endian>; |
| 922 | type NoteHeader = elf::NoteHeader32<Endian>; |
| 923 | type Dyn = elf::Dyn64<Endian>; |
| 924 | type Sym = elf::Sym64<Endian>; |
| 925 | type Rel = elf::Rel64<Endian>; |
| 926 | type Rela = elf::Rela64<Endian>; |
| 927 | type Relr = elf::Relr64<Endian>; |
| 928 | |
| 929 | #[inline ] |
| 930 | fn is_type_64(&self) -> bool { |
| 931 | true |
| 932 | } |
| 933 | |
| 934 | #[inline ] |
| 935 | fn is_type_64_sized() -> bool |
| 936 | where |
| 937 | Self: Sized, |
| 938 | { |
| 939 | true |
| 940 | } |
| 941 | |
| 942 | #[inline ] |
| 943 | fn e_ident(&self) -> &elf::Ident { |
| 944 | &self.e_ident |
| 945 | } |
| 946 | |
| 947 | #[inline ] |
| 948 | fn e_type(&self, endian: Self::Endian) -> u16 { |
| 949 | self.e_type.get(endian) |
| 950 | } |
| 951 | |
| 952 | #[inline ] |
| 953 | fn e_machine(&self, endian: Self::Endian) -> u16 { |
| 954 | self.e_machine.get(endian) |
| 955 | } |
| 956 | |
| 957 | #[inline ] |
| 958 | fn e_version(&self, endian: Self::Endian) -> u32 { |
| 959 | self.e_version.get(endian) |
| 960 | } |
| 961 | |
| 962 | #[inline ] |
| 963 | fn e_entry(&self, endian: Self::Endian) -> Self::Word { |
| 964 | self.e_entry.get(endian) |
| 965 | } |
| 966 | |
| 967 | #[inline ] |
| 968 | fn e_phoff(&self, endian: Self::Endian) -> Self::Word { |
| 969 | self.e_phoff.get(endian) |
| 970 | } |
| 971 | |
| 972 | #[inline ] |
| 973 | fn e_shoff(&self, endian: Self::Endian) -> Self::Word { |
| 974 | self.e_shoff.get(endian) |
| 975 | } |
| 976 | |
| 977 | #[inline ] |
| 978 | fn e_flags(&self, endian: Self::Endian) -> u32 { |
| 979 | self.e_flags.get(endian) |
| 980 | } |
| 981 | |
| 982 | #[inline ] |
| 983 | fn e_ehsize(&self, endian: Self::Endian) -> u16 { |
| 984 | self.e_ehsize.get(endian) |
| 985 | } |
| 986 | |
| 987 | #[inline ] |
| 988 | fn e_phentsize(&self, endian: Self::Endian) -> u16 { |
| 989 | self.e_phentsize.get(endian) |
| 990 | } |
| 991 | |
| 992 | #[inline ] |
| 993 | fn e_phnum(&self, endian: Self::Endian) -> u16 { |
| 994 | self.e_phnum.get(endian) |
| 995 | } |
| 996 | |
| 997 | #[inline ] |
| 998 | fn e_shentsize(&self, endian: Self::Endian) -> u16 { |
| 999 | self.e_shentsize.get(endian) |
| 1000 | } |
| 1001 | |
| 1002 | #[inline ] |
| 1003 | fn e_shnum(&self, endian: Self::Endian) -> u16 { |
| 1004 | self.e_shnum.get(endian) |
| 1005 | } |
| 1006 | |
| 1007 | #[inline ] |
| 1008 | fn e_shstrndx(&self, endian: Self::Endian) -> u16 { |
| 1009 | self.e_shstrndx.get(endian) |
| 1010 | } |
| 1011 | } |
| 1012 | |