class Section64(IndexedHeader):
ENDIAN = None
FIELDS = (
NullTerminatedStringField('sectname', '16s'),
NullTerminatedStringField('segname', '16s'),
HexField('addr', 'Q'),
Field('size', 'Q'),
Field('offset', 'I'),
Field('align', 'I'),
Field('reloff', 'I'),
Field('nreloc', 'I'),
HexField('flags', 'I'),
Field('reserved1', 'I'),
Field('reserved2', 'I'),
Field('reserved3', 'I'),
)
NEXT_INDEX = 1
def __init__(self, bytes_=None, **kwargs):
self.sectname = None
self.segname = None
self.addr = None
self.size = None
self.offset = None
self.align = None
self.reloff = None
self.nreloc = None
self.flags = None
self.reserved1 = None
self.reserved2 = None
super(Section64, self).__init__('section_64', bytes_, **kwargs)
def symbol(self, matched_idx):
assert 0 <= matched_idx < self.num_matched
table_idx = 0
section_desc = ''
for mapping in self._filter_mappings:
mapping_size = len(mapping)
if matched_idx >= mapping_size:
matched_idx -= mapping_size
table_idx += 1
continue
(index, n_strx, n_type, n_sect, n_desc, n_value, symbol_name) = \
self._symbol_tables[table_idx].symbols[mapping[matched_idx]]
nlist = Nlist64(index=index,
n_strx=n_strx,
n_type=n_type,
n_sect=n_sect,
n_desc=n_desc,
n_value=n_value)
if nlist.n_sect != 0:
this_section = self._sections[nlist.n_sect]
section_desc = '%s, %s' % \
(NullTerminatedStringField.get_string(this_section.segname),
NullTerminatedStringField.get_string(this_section.sectname))
return nlist, symbol_name, section_desc
assert False # should never get here
def __init__(self, seg_name, sect_name, bytes_):
self.seg_name = None
self.sect_name = None
seg_name = NullTerminatedStringField.get_string(seg_name)
sect_name = NullTerminatedStringField.get_string(sect_name)
super(SectionBlock, self).__init__('Section: %s %s' % (seg_name, sect_name),
seg_name=seg_name, sect_name=sect_name)
self.parse_bytes(bytes_)
def __init__(self, seg_name, sect_name, bytes_):
self.seg_name = None
self.sect_name = None
seg_name = NullTerminatedStringField.get_string(seg_name)
sect_name = NullTerminatedStringField.get_string(sect_name)
super(SectionBlock,
self).__init__('Section: %s %s' % (seg_name, sect_name),
seg_name=seg_name,
sect_name=sect_name)
self.parse_bytes(bytes_)
def parse(self, section_desc):
section = section_desc.section
self.initialize(section.offset, section.size)
# Get the segment and section names
seg_name = NullTerminatedStringField.get_string(section.segname)
sect_name = NullTerminatedStringField.get_string(section.sectname)
bytes_ = self.get_bytes()
if seg_name == '__TEXT':
data_section = TextSection(sect_name, bytes_)
elif seg_name == '__DATA':
data_section = DataSection(sect_name, bytes_)
else:
data_section = SectionBlock(seg_name, sect_name, bytes_)
# If the section is inside a encrypted region (specificed by LC_ENCRYPTION_INFO),
# we cannot parse it because we don't have the decryption key. So, we just
# create a block without trying to parse its content.
if self.mach_o.is_section_encrypted(section):
data_section.name += ' [ENCRYPTED]'
self.add_subrange(data_section, section.size)
return
if section.offset == 0:
# .bss and .common sections only exist in VM but not in the file. So, they have an offset of 0
# which aliases with the mach header. We do not add any subrange for these sections since
# there is no data to parse / display.
# TODO - in some iOS binraries, offset is set to 0 for many sections that should have data
# Need to study them more to determine if offset is just not set proerly and we can
# compute the offset from the first data section and the VM address.
return
elif section_desc.is_cstring():
data_section = CstringSection(bytes_)
cstring_br = self.add_subrange(data_section, section.size)
for (offset, string) in data_section.items():
unescaped_string = Unescape.convert(string)
cstring_br.add_subrange(offset,
len(string) + 1,
data=Cstring(unescaped_string))
elif section_desc.is_objc_methname():
data_section = ObjCMethodNameSection(bytes_)
obj_methname_br = self.add_subrange(data_section, section.size)
for (offset, string) in data_section.items():
unescaped_string = Unescape.convert(string)
obj_methname_br.add_subrange(
offset,
len(string) + 1,
data=ObjCMethodName(unescaped_string))
else:
self.add_subrange(data_section, section.size)
class SegmentCommand(LoadCommandHeader):
ENDIAN = None
FIELDS = (
MagicField('cmd', 'I', {LoadCommandCommand.COMMANDS['LC_SEGMENT']: 'LC_SEGMENT'}),
Field('cmdsize', 'I'),
NullTerminatedStringField('segname', '16s'),
HexField('vmaddr', 'I'),
Field('vmsize', 'I'),
Field('fileoff', 'I'),
Field('filesize', 'I'),
Field('maxprot', 'I'),
Field('initprot', 'I'),
Field('nsects', 'I'),
HexField('flags', 'I'),
)
def __init__(self, bytes_=None, **kwargs):
self.segname = None
self.vmaddr = None
self.vmsize = None
self.fileoff = None
self.filesize = None
self.maxprot = None
self.initprot = None
self.nsects = None
self.flags = None
super(SegmentCommand, self).__init__('segment_command', bytes_, **kwargs)
def __init__(self, sect_name, bytes_):
sect_name = NullTerminatedStringField.get_string(sect_name)
super(TextSection, self).__init__('__TEXT', sect_name, bytes_)
self.name = 'TextSection: %s' % sect_name
def __init__(self, sect_name, bytes_):
sect_name = NullTerminatedStringField.get_string(sect_name)
super(DataSection, self).__init__('__DATA', sect_name, bytes_)
self.name = 'DataSection: %s' % sect_name
def __init__(self, seg_name):
self.seg_name = None
seg_name = NullTerminatedStringField.get_string(seg_name)
super(SegmentBlock, self).__init__('Segment: %s' % seg_name, color='cyan', bold=True, seg_name=seg_name)
def __init__(self, sect_name, bytes_):
sect_name = NullTerminatedStringField.get_string(sect_name)
super(TextSection, self).__init__('__TEXT', sect_name, bytes_)
self.name = 'TextSection: %s' % sect_name
def __init__(self, sect_name, bytes_):
sect_name = NullTerminatedStringField.get_string(sect_name)
super(DataSection, self).__init__('__DATA', sect_name, bytes_)
self.name = 'DataSection: %s' % sect_name