use alloc::vec::Vec;
use core::fmt::Debug;
use core::{mem, str};
use crate::read::{
self, util, Architecture, Error, FileFlags, Object, ReadError, SectionIndex, StringTable,
Symbol, SymbolIndex, SymbolMap,
};
use crate::{elf, endian, Bytes, Endian, Endianness, Pod, U32};
use super::{
parse_symbol, CompressionHeader, ElfSection, ElfSectionIterator, ElfSegment,
ElfSegmentIterator, ElfSymbolIterator, NoteHeader, ProgramHeader, Rela, RelocationSections,
SectionHeader, SectionTable, Sym, SymbolTable,
};
pub type ElfFile32<'data, Endian = Endianness> = ElfFile<'data, elf::FileHeader32<Endian>>;
pub type ElfFile64<'data, Endian = Endianness> = ElfFile<'data, elf::FileHeader64<Endian>>;
#[derive(Debug)]
pub struct ElfFile<'data, Elf: FileHeader> {
pub(super) endian: Elf::Endian,
pub(super) data: Bytes<'data>,
pub(super) header: &'data Elf,
pub(super) segments: &'data [Elf::ProgramHeader],
pub(super) sections: SectionTable<'data, Elf>,
pub(super) relocations: RelocationSections,
pub(super) symbols: SymbolTable<'data, Elf>,
pub(super) dynamic_symbols: SymbolTable<'data, Elf>,
}
impl<'data, Elf: FileHeader> ElfFile<'data, Elf> {
pub fn parse(data: &'data [u8]) -> read::Result<Self> {
let data = Bytes(data);
let header = Elf::parse(data)?;
let endian = header.endian()?;
let segments = header.program_headers(endian, data)?;
let sections = header.sections(endian, data)?;
let symbols = sections.symbols(endian, data, elf::SHT_SYMTAB)?;
let dynamic_symbols = sections.symbols(endian, data, elf::SHT_DYNSYM)?;
let relocations = sections.relocation_sections(endian, symbols.section())?;
Ok(ElfFile {
endian,
header,
segments,
sections,
relocations,
symbols,
dynamic_symbols,
data,
})
}
fn raw_section_by_name<'file>(
&'file self,
section_name: &str,
) -> Option<ElfSection<'data, 'file, Elf>> {
self.sections
.section_by_name(self.endian, section_name.as_bytes())
.map(|(index, section)| ElfSection {
file: self,
index: SectionIndex(index),
section,
})
}
#[cfg(feature = "compression")]
fn zdebug_section_by_name<'file>(
&'file self,
section_name: &str,
) -> Option<ElfSection<'data, 'file, Elf>> {
if !section_name.starts_with(".debug_") {
return None;
}
self.raw_section_by_name(&format!(".zdebug_{}", §ion_name[7..]))
}
#[cfg(not(feature = "compression"))]
fn zdebug_section_by_name<'file>(
&'file self,
_section_name: &str,
) -> Option<ElfSection<'data, 'file, Elf>> {
None
}
}
impl<'data, Elf: FileHeader> read::private::Sealed for ElfFile<'data, Elf> {}
impl<'data, 'file, Elf> Object<'data, 'file> for ElfFile<'data, Elf>
where
'data: 'file,
Elf: FileHeader,
{
type Segment = ElfSegment<'data, 'file, Elf>;
type SegmentIterator = ElfSegmentIterator<'data, 'file, Elf>;
type Section = ElfSection<'data, 'file, Elf>;
type SectionIterator = ElfSectionIterator<'data, 'file, Elf>;
type SymbolIterator = ElfSymbolIterator<'data, 'file, Elf>;
fn architecture(&self) -> Architecture {
match self.header.e_machine(self.endian) {
elf::EM_ARM => Architecture::Arm,
elf::EM_AARCH64 => Architecture::Aarch64,
elf::EM_386 => Architecture::I386,
elf::EM_X86_64 => Architecture::X86_64,
elf::EM_MIPS => Architecture::Mips,
_ => Architecture::Unknown,
}
}
#[inline]
fn is_little_endian(&self) -> bool {
self.header.is_little_endian()
}
#[inline]
fn is_64(&self) -> bool {
self.header.is_class_64()
}
fn segments(&'file self) -> ElfSegmentIterator<'data, 'file, Elf> {
ElfSegmentIterator {
file: self,
iter: self.segments.iter(),
}
}
fn section_by_name(&'file self, section_name: &str) -> Option<ElfSection<'data, 'file, Elf>> {
self.raw_section_by_name(section_name)
.or_else(|| self.zdebug_section_by_name(section_name))
}
fn section_by_index(
&'file self,
index: SectionIndex,
) -> read::Result<ElfSection<'data, 'file, Elf>> {
let section = self.sections.section(index.0)?;
Ok(ElfSection {
file: self,
index,
section,
})
}
fn sections(&'file self) -> ElfSectionIterator<'data, 'file, Elf> {
ElfSectionIterator {
file: self,
iter: self.sections.iter().enumerate(),
}
}
fn symbol_by_index(&self, index: SymbolIndex) -> read::Result<Symbol<'data>> {
let symbol = self.symbols.symbol(index.0)?;
let shndx = self.symbols.shndx(index.0);
let name = symbol.name(self.endian, self.symbols.strings()).ok();
Ok(parse_symbol::<Elf>(
self.endian,
index.0,
symbol,
name,
shndx,
))
}
fn symbols(&'file self) -> ElfSymbolIterator<'data, 'file, Elf> {
ElfSymbolIterator {
file: self,
symbols: self.symbols,
index: 0,
}
}
fn dynamic_symbols(&'file self) -> ElfSymbolIterator<'data, 'file, Elf> {
ElfSymbolIterator {
file: self,
symbols: self.dynamic_symbols,
index: 0,
}
}
fn symbol_map(&self) -> SymbolMap<'data> {
let mut symbols: Vec<_> = self
.symbols()
.map(|(_, s)| s)
.filter(SymbolMap::filter)
.collect();
symbols.sort_by_key(|x| x.address);
SymbolMap { symbols }
}
fn has_debug_symbols(&self) -> bool {
for section in self.sections.iter() {
if let Ok(name) = self.sections.section_name(self.endian, section) {
if name == b".debug_info" || name == b".zdebug_info" {
return true;
}
}
}
false
}
fn build_id(&self) -> read::Result<Option<&'data [u8]>> {
let endian = self.endian;
if !self.sections.is_empty() {
for section in self.sections.iter() {
if let Some(mut notes) = section.notes(endian, self.data)? {
while let Some(note) = notes.next()? {
if note.name() == elf::ELF_NOTE_GNU
&& note.n_type(endian) == elf::NT_GNU_BUILD_ID
{
return Ok(Some(note.desc()));
}
}
}
}
} else {
for segment in self.segments {
if let Some(mut notes) = segment.notes(endian, self.data)? {
while let Some(note) = notes.next()? {
if note.name() == elf::ELF_NOTE_GNU
&& note.n_type(endian) == elf::NT_GNU_BUILD_ID
{
return Ok(Some(note.desc()));
}
}
}
}
}
Ok(None)
}
fn gnu_debuglink(&self) -> read::Result<Option<(&'data [u8], u32)>> {
let section = match self.raw_section_by_name(".gnu_debuglink") {
Some(section) => section,
None => return Ok(None),
};
let data = section
.section
.data(self.endian, self.data)
.read_error("Invalid ELF .gnu_debuglink section offset or size")?;
let filename = data
.read_string_at(0)
.read_error("Missing ELF .gnu_debuglink filename")?;
let crc_offset = util::align(filename.len() + 1, 4);
let crc = data
.read_at::<U32<_>>(crc_offset)
.read_error("Missing ELF .gnu_debuglink crc")?
.get(self.endian);
Ok(Some((filename, crc)))
}
fn entry(&self) -> u64 {
self.header.e_entry(self.endian).into()
}
fn flags(&self) -> FileFlags {
FileFlags::Elf {
e_flags: self.header.e_flags(self.endian),
}
}
}
#[allow(missing_docs)]
pub trait FileHeader: Debug + Pod {
type Word: Into<u64>;
type Sword: Into<i64>;
type Endian: endian::Endian;
type ProgramHeader: ProgramHeader<Endian = Self::Endian>;
type SectionHeader: SectionHeader<Endian = Self::Endian>;
type CompressionHeader: CompressionHeader<Endian = Self::Endian>;
type NoteHeader: NoteHeader<Endian = Self::Endian>;
type Sym: Sym<Endian = Self::Endian>;
type Rel: Clone + Pod;
type Rela: Rela<Endian = Self::Endian> + From<Self::Rel>;
fn is_type_64(&self) -> bool;
fn e_ident(&self) -> &elf::Ident;
fn e_type(&self, endian: Self::Endian) -> u16;
fn e_machine(&self, endian: Self::Endian) -> u16;
fn e_version(&self, endian: Self::Endian) -> u32;
fn e_entry(&self, endian: Self::Endian) -> Self::Word;
fn e_phoff(&self, endian: Self::Endian) -> Self::Word;
fn e_shoff(&self, endian: Self::Endian) -> Self::Word;
fn e_flags(&self, endian: Self::Endian) -> u32;
fn e_ehsize(&self, endian: Self::Endian) -> u16;
fn e_phentsize(&self, endian: Self::Endian) -> u16;
fn e_phnum(&self, endian: Self::Endian) -> u16;
fn e_shentsize(&self, endian: Self::Endian) -> u16;
fn e_shnum(&self, endian: Self::Endian) -> u16;
fn e_shstrndx(&self, endian: Self::Endian) -> u16;
fn parse<'data>(data: Bytes<'data>) -> read::Result<&'data Self> {
let header = data
.read_at::<Self>(0)
.read_error("Invalid ELF header size or alignment")?;
if !header.is_supported() {
return Err(Error("Unsupported ELF header"));
}
Ok(header)
}
fn is_supported(&self) -> bool {
let ident = self.e_ident();
ident.magic == elf::ELFMAG
&& (self.is_type_64() || self.is_class_32())
&& (!self.is_type_64() || self.is_class_64())
&& (self.is_little_endian() || self.is_big_endian())
&& ident.version == elf::EV_CURRENT
}
fn is_class_32(&self) -> bool {
self.e_ident().class == elf::ELFCLASS32
}
fn is_class_64(&self) -> bool {
self.e_ident().class == elf::ELFCLASS64
}
fn is_little_endian(&self) -> bool {
self.e_ident().data == elf::ELFDATA2LSB
}
fn is_big_endian(&self) -> bool {
self.e_ident().data == elf::ELFDATA2MSB
}
fn endian(&self) -> read::Result<Self::Endian> {
Self::Endian::from_big_endian(self.is_big_endian()).read_error("Unsupported ELF endian")
}
fn section_0<'data>(
&self,
endian: Self::Endian,
data: Bytes<'data>,
) -> read::Result<Option<&'data Self::SectionHeader>> {
let shoff: u64 = self.e_shoff(endian).into();
if shoff == 0 {
return Ok(None);
}
let shentsize = self.e_shentsize(endian) as usize;
if shentsize != mem::size_of::<Self::SectionHeader>() {
return Err(Error("Invalid ELF section header entry size"));
}
data.read_at(shoff as usize)
.map(Some)
.read_error("Invalid ELF section header offset or size")
}
fn phnum<'data>(&self, endian: Self::Endian, data: Bytes<'data>) -> read::Result<usize> {
let e_phnum = self.e_phnum(endian);
if e_phnum < elf::PN_XNUM {
Ok(e_phnum as usize)
} else if let Some(section_0) = self.section_0(endian, data)? {
Ok(section_0.sh_info(endian) as usize)
} else {
Err(Error("Missing ELF section headers for e_phnum overflow"))
}
}
fn shnum<'data>(&self, endian: Self::Endian, data: Bytes<'data>) -> read::Result<usize> {
let e_shnum = self.e_shnum(endian);
if e_shnum > 0 {
Ok(e_shnum as usize)
} else if let Some(section_0) = self.section_0(endian, data)? {
let size: u64 = section_0.sh_size(endian).into();
Ok(size as usize)
} else {
Ok(0)
}
}
fn shstrndx<'data>(&self, endian: Self::Endian, data: Bytes<'data>) -> read::Result<u32> {
let e_shstrndx = self.e_shstrndx(endian);
let index = if e_shstrndx != elf::SHN_XINDEX {
e_shstrndx.into()
} else if let Some(section_0) = self.section_0(endian, data)? {
section_0.sh_link(endian)
} else {
return Err(Error("Missing ELF section headers for e_shstrndx overflow"));
};
if index == 0 {
return Err(Error("Missing ELF e_shstrndx"));
}
Ok(index)
}
fn program_headers<'data>(
&self,
endian: Self::Endian,
data: Bytes<'data>,
) -> read::Result<&'data [Self::ProgramHeader]> {
let phoff: u64 = self.e_phoff(endian).into();
if phoff == 0 {
return Ok(&[]);
}
let phnum = self.phnum(endian, data)?;
if phnum == 0 {
return Ok(&[]);
}
let phentsize = self.e_phentsize(endian) as usize;
if phentsize != mem::size_of::<Self::ProgramHeader>() {
return Err(Error("Invalid ELF program header entry size"));
}
data.read_slice_at(phoff as usize, phnum)
.read_error("Invalid ELF program header size or alignment")
}
fn section_headers<'data>(
&self,
endian: Self::Endian,
data: Bytes<'data>,
) -> read::Result<&'data [Self::SectionHeader]> {
let shoff: u64 = self.e_shoff(endian).into();
if shoff == 0 {
return Ok(&[]);
}
let shnum = self.shnum(endian, data)?;
if shnum == 0 {
return Ok(&[]);
}
let shentsize = self.e_shentsize(endian) as usize;
if shentsize != mem::size_of::<Self::SectionHeader>() {
return Err(Error("Invalid ELF section header entry size"));
}
data.read_slice_at(shoff as usize, shnum)
.read_error("Invalid ELF section header offset/size/alignment")
}
fn section_strings<'data>(
&self,
endian: Self::Endian,
data: Bytes<'data>,
sections: &[Self::SectionHeader],
) -> read::Result<StringTable<'data>> {
if sections.is_empty() {
return Ok(StringTable::default());
}
let index = self.shstrndx(endian, data)? as usize;
let shstrtab = sections.get(index).read_error("Invalid ELF e_shstrndx")?;
let data = shstrtab
.data(endian, data)
.read_error("Invalid ELF shstrtab data")?;
Ok(StringTable::new(data))
}
fn sections<'data>(
&self,
endian: Self::Endian,
data: Bytes<'data>,
) -> read::Result<SectionTable<'data, Self>> {
let sections = self.section_headers(endian, data)?;
let strings = self.section_strings(endian, data, sections)?;
Ok(SectionTable::new(sections, strings))
}
}
impl<Endian: endian::Endian> FileHeader for elf::FileHeader32<Endian> {
type Word = u32;
type Sword = i32;
type Endian = Endian;
type ProgramHeader = elf::ProgramHeader32<Endian>;
type SectionHeader = elf::SectionHeader32<Endian>;
type CompressionHeader = elf::CompressionHeader32<Endian>;
type NoteHeader = elf::NoteHeader32<Endian>;
type Sym = elf::Sym32<Endian>;
type Rel = elf::Rel32<Endian>;
type Rela = elf::Rela32<Endian>;
#[inline]
fn is_type_64(&self) -> bool {
false
}
#[inline]
fn e_ident(&self) -> &elf::Ident {
&self.e_ident
}
#[inline]
fn e_type(&self, endian: Self::Endian) -> u16 {
self.e_type.get(endian)
}
#[inline]
fn e_machine(&self, endian: Self::Endian) -> u16 {
self.e_machine.get(endian)
}
#[inline]
fn e_version(&self, endian: Self::Endian) -> u32 {
self.e_version.get(endian)
}
#[inline]
fn e_entry(&self, endian: Self::Endian) -> Self::Word {
self.e_entry.get(endian)
}
#[inline]
fn e_phoff(&self, endian: Self::Endian) -> Self::Word {
self.e_phoff.get(endian)
}
#[inline]
fn e_shoff(&self, endian: Self::Endian) -> Self::Word {
self.e_shoff.get(endian)
}
#[inline]
fn e_flags(&self, endian: Self::Endian) -> u32 {
self.e_flags.get(endian)
}
#[inline]
fn e_ehsize(&self, endian: Self::Endian) -> u16 {
self.e_ehsize.get(endian)
}
#[inline]
fn e_phentsize(&self, endian: Self::Endian) -> u16 {
self.e_phentsize.get(endian)
}
#[inline]
fn e_phnum(&self, endian: Self::Endian) -> u16 {
self.e_phnum.get(endian)
}
#[inline]
fn e_shentsize(&self, endian: Self::Endian) -> u16 {
self.e_shentsize.get(endian)
}
#[inline]
fn e_shnum(&self, endian: Self::Endian) -> u16 {
self.e_shnum.get(endian)
}
#[inline]
fn e_shstrndx(&self, endian: Self::Endian) -> u16 {
self.e_shstrndx.get(endian)
}
}
impl<Endian: endian::Endian> FileHeader for elf::FileHeader64<Endian> {
type Word = u64;
type Sword = i64;
type Endian = Endian;
type ProgramHeader = elf::ProgramHeader64<Endian>;
type SectionHeader = elf::SectionHeader64<Endian>;
type CompressionHeader = elf::CompressionHeader64<Endian>;
type NoteHeader = elf::NoteHeader32<Endian>;
type Sym = elf::Sym64<Endian>;
type Rel = elf::Rel64<Endian>;
type Rela = elf::Rela64<Endian>;
#[inline]
fn is_type_64(&self) -> bool {
true
}
#[inline]
fn e_ident(&self) -> &elf::Ident {
&self.e_ident
}
#[inline]
fn e_type(&self, endian: Self::Endian) -> u16 {
self.e_type.get(endian)
}
#[inline]
fn e_machine(&self, endian: Self::Endian) -> u16 {
self.e_machine.get(endian)
}
#[inline]
fn e_version(&self, endian: Self::Endian) -> u32 {
self.e_version.get(endian)
}
#[inline]
fn e_entry(&self, endian: Self::Endian) -> Self::Word {
self.e_entry.get(endian)
}
#[inline]
fn e_phoff(&self, endian: Self::Endian) -> Self::Word {
self.e_phoff.get(endian)
}
#[inline]
fn e_shoff(&self, endian: Self::Endian) -> Self::Word {
self.e_shoff.get(endian)
}
#[inline]
fn e_flags(&self, endian: Self::Endian) -> u32 {
self.e_flags.get(endian)
}
#[inline]
fn e_ehsize(&self, endian: Self::Endian) -> u16 {
self.e_ehsize.get(endian)
}
#[inline]
fn e_phentsize(&self, endian: Self::Endian) -> u16 {
self.e_phentsize.get(endian)
}
#[inline]
fn e_phnum(&self, endian: Self::Endian) -> u16 {
self.e_phnum.get(endian)
}
#[inline]
fn e_shentsize(&self, endian: Self::Endian) -> u16 {
self.e_shentsize.get(endian)
}
#[inline]
fn e_shnum(&self, endian: Self::Endian) -> u16 {
self.e_shnum.get(endian)
}
#[inline]
fn e_shstrndx(&self, endian: Self::Endian) -> u16 {
self.e_shstrndx.get(endian)
}
}