Added section attribute to elf_symbol and get_symbols() function to elf_section.

This commit is contained in:
Nicolas 2025-02-28 15:13:36 +01:00
parent 99bd71f9b8
commit 675146e744
1 changed files with 23 additions and 9 deletions

View File

@ -33,6 +33,8 @@ class elf_symbol():
name: Name of the symbol
section: section where the symbol data is placed
index: Absolut index in the symbol table
info: Type of the symbol
@ -55,6 +57,8 @@ class elf_symbol():
else:
self.name = ''
self.section: elf_section | None = self.file.sections[self['st_shndx']] if self['st_shndx'] < len(self.file.sections) else None
self.index = index
self.info, self.description = fdat.st_info_values[fields['st_info'] & 0x0F]
@ -68,7 +72,8 @@ class elf_symbol():
Returns:
Symbol data
"""
offset = self.file.sections[self['st_shndx']]['sh_offset'] + self['st_value']
assert self.section, 'This symbol is not associated to a data section'
offset = self.section['sh_offset'] + self['st_value']
return self.file.read_bytes(offset, self['st_size'])
def read_data_hex(self) -> str:
@ -76,7 +81,7 @@ class elf_symbol():
def get_relocations(self) -> 'relocation_list':
"""List all relocations that are pointing to this symbol.
The symbol must be of type SHT_PROGBITS (program code). Therefore
The symbol section must be of type SHT_PROGBITS (program code). Therefore
this function lists typically all relocations that will be
applied to the function represented by the symbol.
@ -84,10 +89,9 @@ class elf_symbol():
List of relocations
"""
ret: list[elf_relocation] = list()
section = self.file.sections[self.fields['st_shndx']]
assert section.type == 'SHT_PROGBITS'
assert self.section and self.section.type == 'SHT_PROGBITS'
for reloc in self.file.get_relocations():
if reloc.target_section == section:
if reloc.target_section == self.section:
offset = reloc['r_offset'] - self['st_value']
if 0 <= offset < self['st_size']:
ret.append(reloc)
@ -158,6 +162,14 @@ class elf_section():
"""
return self.file.read_bytes(self['sh_offset'], self['sh_size'])
def get_symbols(self) -> 'symbol_list':
"""Lists all ELF symbols associated with this section
Returns:
Symbol list
"""
return symbol_list(self.file._list_symbols(self.index))
def get_data_hex(self) -> str:
data = self.file.read_bytes(self['sh_offset'], self['sh_size'])
return ' '.join(f'{d:02X}' for d in data)
@ -369,14 +381,15 @@ class elf_file:
string_table_section: The string table section (first section with
the name .strtab)
"""
def __init__(self, data: bytes):
def __init__(self, data: bytes | bytearray):
assert isinstance(data, (bytes, bytearray)), 'Binary ELF data must be provided as bytes or bytearray.'
self._data = data
# Defaults required for function _read_int_from_elf_field
self.bit_width = 32
self.byteorder: Literal['little', 'big'] = 'little'
assert self._read_bytes_from_elf_field('e_ident[EI_MAG]') == bytes([0x7F, 0x45, 0x4c, 0x46]), 'Not an ELF file'
assert self._read_bytes_from_elf_field('e_ident[EI_MAG]') == b'\x7fELF', 'Not an ELF file'
self.bit_width = {1: 32, 2: 64}[self._read_int_from_elf_field('e_ident[EI_CLASS]')]
@ -414,7 +427,7 @@ class elf_file:
offs = self.fields['e_shoff'] + i * self.fields['e_shentsize']
yield {fn: self._read_from_sh_field(offs, fn) for fn in fdat.section_header.keys()}
def _list_symbols(self) -> Generator[elf_symbol, None, None]:
def _list_symbols(self, section_index: int | None = None) -> Generator[elf_symbol, None, None]:
if self.symbol_table_section:
offs = self.symbol_table_section['sh_offset']
@ -434,6 +447,7 @@ class elf_file:
ret['st_value'] = self.read_int(i + 8, 8)
ret['st_size'] = self.read_int(i + 16, 8)
if section_index is None or section_index == ret['st_shndx']:
yield elf_symbol(self, ret, j)
def get_relocations(self, reloc_section: elf_section | str | list[str] | None = None) -> relocation_list: