def _get_rpath(self, header):
"""Returns a generator of RPATH string values in the header."""
for (idx, (lc, cmd, data)) in enumerate(header.commands):
if lc.cmd == mach_o.LC_RPATH:
ofs = cmd.path - sizeof(lc.__class__) - sizeof(cmd.__class__)
yield data[ofs:data.find(b'\x00', ofs)].decode(
sys.getfilesystemencoding())
def _add_rpath_to_header(header, rpath):
"""Add an LC_RPATH load command to a MachOHeader.
Parameters
----------
header: MachOHeader instances
A mach-o header to add rpath to
rpath: str
The rpath to add to the given header
"""
if header.header.magic in (macholib.mach_o.MH_MAGIC,
macholib.mach_o.MH_CIGAM):
pad_to = 4
else:
pad_to = 8
data = macho_path_as_data(rpath, pad_to=pad_to)
header_size = sizeof(macholib.mach_o.load_command) + sizeof(
macholib.mach_o.rpath_command)
rem = (header_size + len(data)) % pad_to
if rem > 0:
data += b'\x00' * (pad_to - rem)
command_size = header_size + len(data)
cmd = macholib.mach_o.rpath_command(header_size, _endian_=header.endian)
lc = macholib.mach_o.load_command(macholib.mach_o.LC_RPATH,
command_size,
_endian_=header.endian)
header.commands.append((lc, cmd, data))
header.header.ncmds += 1
header.changedHeaderSizeBy(command_size)
def _add_rpath_to_header(header, rpath):
"""Add an LC_RPATH load command to a MachOHeader.
Parameters
----------
header: MachOHeader instances
A mach-o header to add rpath to
rpath: str
The rpath to add to the given header
"""
if header.header.magic in (macholib.mach_o.MH_MAGIC, macholib.mach_o.MH_CIGAM):
pad_to = 4
else:
pad_to = 8
data = macho_path_as_data(rpath, pad_to=pad_to)
header_size = sizeof(macholib.mach_o.load_command) + sizeof(macholib.mach_o.rpath_command)
rem = (header_size + len(data)) % pad_to
if rem > 0:
data += b'\x00' * (pad_to - rem)
command_size = header_size + len(data)
cmd = macholib.mach_o.rpath_command(header_size, _endian_=header.endian)
lc = macholib.mach_o.load_command(macholib.mach_o.LC_RPATH, command_size,
_endian_=header.endian)
header.commands.append((lc, cmd, data))
header.header.ncmds += 1
header.changedHeaderSizeBy(command_size)
def _add_dependency_to_header(header, new_dependency, compatibility_version,
current_version):
"""Add an LC_LOAD_DYLIB load command to a MachOHeader.
Parameters
----------
header: MachOHeader instances
A mach-o header to add dependency to
new_dependency: str
Name of the dependency to be added to the header
compatibility_version: str
Compatibility Version of the new dependency
Example: 1.2.3
current_version: str
Current Version of the new dependency
Example: 1.2.3
"""
if header.header.magic in (macholib.mach_o.MH_MAGIC,
macholib.mach_o.MH_CIGAM):
pad_to = 4
else:
pad_to = 8
data = macho_path_as_data(new_dependency, pad_to=pad_to)
header_size = sizeof(macholib.mach_o.load_command) + sizeof(
macholib.mach_o.dylib_command)
rem = (header_size + len(data)) % pad_to
if rem > 0:
data += b'\x00' * (pad_to - rem)
command_size = header_size + len(data)
cmd = macholib.mach_o.dylib_command(header_size, _endian_=header.endian)
# We assume that the compatibility version data is in the format major.minor.rev version numbers. Example: 1.2.3
version_array = compatibility_version.split('.')
compatibility_version_object = macholib.mach_o.mach_version_helper(
int(version_array[0]), int(version_array[1]), int(version_array[2]))
cmd.compatibility_version = compatibility_version_object
# We assume that the current version data is in the format major.minor.rev version numbers. Example: 1.2.3
version_array = current_version.split('.')
current_version_object = macholib.mach_o.mach_version_helper(
int(version_array[0]), int(version_array[1]), int(version_array[2]))
cmd.current_version = current_version_object
lc = macholib.mach_o.load_command(macholib.mach_o.LC_LOAD_DYLIB,
command_size,
_endian_=header.endian)
header.commands.append((lc, cmd, data))
header.header.ncmds += 1
header.changedHeaderSizeBy(command_size)
def test_sizeof(self):
self.assertEqual(ptypes.sizeof(b"foobar"), 6)
self.assertRaises(ValueError, ptypes.sizeof, [])
self.assertRaises(ValueError, ptypes.sizeof, {})
self.assertRaises(ValueError, ptypes.sizeof, b"foo".decode('ascii'))
class M (object):
pass
m = M()
m._size_ = 42
self.assertEqual(ptypes.sizeof(m), 42)
def test_sizeof(self):
self.assertEqual(ptypes.sizeof(b"foobar"), 6)
self.assertRaises(ValueError, ptypes.sizeof, [])
self.assertRaises(ValueError, ptypes.sizeof, {})
self.assertRaises(ValueError, ptypes.sizeof, b"foo".decode('ascii'))
class M(object):
pass
m = M()
m._size_ = 42
self.assertEqual(ptypes.sizeof(m), 42)
def verifyType(self, ptype, size, pytype, values):
self.assertEqual(ptypes.sizeof(ptype), size)
self.assertIsSubclass(ptype, pytype)
for v in values:
pv = ptype(v)
packed = pv.to_str()
self.assertIsInstance(packed, bytes)
self.assertEqual(len(packed), size)
unp = ptype.from_str(packed)
self.assertIsInstance(unp, ptype)
self.assertEqual(unp, pv)
fp = BytesIO(packed)
unp = ptype.from_fileobj(fp)
fp.close()
self.assertIsInstance(unp, ptype)
self.assertEqual(unp, pv)
fp = BytesIO()
pv.to_fileobj(fp)
data = fp.getvalue()
fp.close()
self.assertEqual(data, packed)
mm = mmap.mmap(-1, size+20)
mm[:] = b'\x00' * (size+20)
pv.to_mmap(mm, 10)
self.assertEqual(ptype.from_mmap(mm, 10), pv)
self.assertEqual(mm[:], (b'\x00'*10) + packed + (b'\x00'*10))
self.assertEqual(ptype.from_tuple((v,)), pv)
def verifyType(self, ptype, size, pytype, values):
self.assertEqual(ptypes.sizeof(ptype), size)
self.assertIsSubclass(ptype, pytype)
for v in values:
pv = ptype(v)
packed = pv.to_str()
self.assertIsInstance(packed, bytes)
self.assertEqual(len(packed), size)
unp = ptype.from_str(packed)
self.assertIsInstance(unp, ptype)
self.assertEqual(unp, pv)
fp = BytesIO(packed)
unp = ptype.from_fileobj(fp)
fp.close()
self.assertIsInstance(unp, ptype)
self.assertEqual(unp, pv)
fp = BytesIO()
pv.to_fileobj(fp)
data = fp.getvalue()
fp.close()
self.assertEqual(data, packed)
mm = mmap.mmap(-1, size + 20)
mm[:] = b'\x00' * (size + 20)
pv.to_mmap(mm, 10)
self.assertEqual(ptype.from_mmap(mm, 10), pv)
self.assertEqual(mm[:], (b'\x00' * 10) + packed + (b'\x00' * 10))
self.assertEqual(ptype.from_tuple((v, )), pv)
def _add_dependency_to_header(header, new_dependency, compatibility_version, current_version):
"""Add an LC_LOAD_DYLIB load command to a MachOHeader.
Parameters
----------
header: MachOHeader instances
A mach-o header to add dependency to
new_dependency: str
Name of the dependency to be added to the header
compatibility_version: str
Compatibility Version of the new dependency
Example: 1.2.3
current_version: str
Current Version of the new dependency
Example: 1.2.3
"""
if header.header.magic in (macholib.mach_o.MH_MAGIC, macholib.mach_o.MH_CIGAM):
pad_to = 4
else:
pad_to = 8
data = macho_path_as_data(new_dependency, pad_to=pad_to)
header_size = sizeof(macholib.mach_o.load_command) + sizeof(macholib.mach_o.dylib_command)
rem = (header_size + len(data)) % pad_to
if rem > 0:
data += b'\x00' * (pad_to - rem)
command_size = header_size + len(data)
cmd = macholib.mach_o.dylib_command(header_size, _endian_=header.endian)
# We assume that the compatibility version data is in the format major.minor.rev version numbers. Example: 1.2.3
version_array = compatibility_version.split('.')
compatibility_version_object = macholib.mach_o.mach_version_helper(int(version_array[0]), int(version_array[1]), int(version_array[2]))
cmd.compatibility_version = compatibility_version_object
# We assume that the current version data is in the format major.minor.rev version numbers. Example: 1.2.3
version_array = current_version.split('.')
current_version_object = macholib.mach_o.mach_version_helper(int(version_array[0]), int(version_array[1]), int(version_array[2]))
cmd.current_version = current_version_object
lc = macholib.mach_o.load_command(macholib.mach_o.LC_LOAD_DYLIB, command_size, _endian_=header.endian)
header.commands.append((lc, cmd, data))
header.header.ncmds += 1
header.changedHeaderSizeBy(command_size)
def generate_dylib_load_command(header, libary_install_name):
""" Generates a LC_LOAD_DYLIB command for the given header and a library install path.
Note: the header must already contain at least one LC_LOAD_DYLIB command (see code comments).
Returns a ready-for-use load_command in terms of macholib.
"""
# One can not simply create instances of `dylib_command` and `load_command` classes,
# because that's just not the way macholib works. If we try then all we'll get is a bunch
# of endian (big/little) issues when these objects are serialized into a file.
# BUT THAT'S PROGRAMMING RIGHT?
# So instead I'll iterate *existing* load commands, find a dyld_command, copy it
# and modify this copy. This existing command is said to be fully initialized.
lc = None
cmd = None
for (command, internal_cmd, data) in header.commands:
if (command.cmd == LC_LOAD_DYLIB) and isinstance(
internal_cmd, dylib_command):
lc = deepcopy(command)
cmd = deepcopy(internal_cmd)
break
if not lc or not cmd:
raise Exception(
"Invalid Mach-O file. I mean, there must be at least one LC_LOAD_DYLIB load command."
)
return None
# Well, now we just replace everything with our own stuff
cmd.timestamp = 0
cmd.current_version = cmd.compatibility_version = 0x1000
# Since we store the library's path just after the load command itself, we need to find out it's offset.
base = sizeof(load_command) + sizeof(dylib_command)
# `name` is rather bad name for this property: actually it means a path string offset
cmd.name = base
# Also the whole thing must be aligned by 4 bytes on 32-bit arches and by 8 bytes on 64-bit arches
align = 4 if header.header.magic == MH_MAGIC else 8
aligned_name = libary_install_name + (b'\x00' *
(align -
(len(libary_install_name) % align)))
# So now we finally can say what size this load_command is
lc.cmdsize = base + len(aligned_name)
return (lc, cmd, aligned_name)
def testBasic(self):
for endian in "><":
kw = dict(_endian_=endian)
MYSTRUCTURE = b"\x00\x01\x02\x03\xFF"
for fn, args in [
("from_str", (MYSTRUCTURE, )),
("from_mmap", (MYSTRUCTURE, 0)),
("from_fileobj", (BytesIO(MYSTRUCTURE), )),
]:
with self.subTest("MYSTRUCTURE", endian=endian, fn=fn):
myStructure = getattr(MyStructure, fn)(*args, **kw)
if endian == ">":
self.assertEqual(myStructure.foo, 0x00010203)
else:
self.assertEqual(myStructure.foo, 0x03020100)
self.assertEqual(myStructure.bar, 0xFF)
self.assertEqual(myStructure._endian_, endian)
self.assertEqual(myStructure.to_str(), MYSTRUCTURE)
MYFUNSTRUCTURE = b"!" + MYSTRUCTURE
for fn, args in [
("from_str", (MYFUNSTRUCTURE, )),
("from_mmap", (MYFUNSTRUCTURE, 0)),
("from_fileobj", (BytesIO(MYFUNSTRUCTURE), )),
]:
with self.subTest("MYFUNSTRUCTURE", fn=fn):
myFunStructure = getattr(MyFunStructure, fn)(*args, **kw)
self.assertEqual(myFunStructure.mystruct, myStructure)
self.assertEqual(myFunStructure.fun, b"!",
(myFunStructure.fun, b"!"))
self.assertEqual(myFunStructure.to_str(), MYFUNSTRUCTURE)
sio = BytesIO()
myFunStructure.to_fileobj(sio)
self.assertEqual(sio.getvalue(), MYFUNSTRUCTURE)
mm = mmap.mmap(-1, ptypes.sizeof(MyFunStructure) * 2)
mm[:] = b"\x00" * (ptypes.sizeof(MyFunStructure) * 2)
myFunStructure.to_mmap(mm, 0)
self.assertEqual(MyFunStructure.from_mmap(mm, 0, **kw),
myFunStructure)
self.assertEqual(mm[:ptypes.sizeof(MyFunStructure)],
MYFUNSTRUCTURE)
self.assertEqual(
mm[ptypes.sizeof(MyFunStructure):],
b"\x00" * ptypes.sizeof(MyFunStructure),
)
myFunStructure.to_mmap(mm, ptypes.sizeof(MyFunStructure))
self.assertEqual(mm[:], MYFUNSTRUCTURE + MYFUNSTRUCTURE)
self.assertEqual(
MyFunStructure.from_mmap(mm, ptypes.sizeof(MyFunStructure),
**kw),
myFunStructure,
)
def generate_dylib_load_command(header, libary_install_name):
""" Generates a LC_LOAD_DYLIB command for the given header and a library install path.
Note: the header must already contain at least one LC_LOAD_DYLIB command (see code comments).
Returns a ready-for-use load_command in terms of macholib.
"""
# One can not simply create instances of `dylib_command` and `load_command` classes,
# because that's just not the way macholib works. If we try then all we'll get is a bunch
# of endian (big/little) issues when these objects are serialized into a file.
# BUT THAT'S PROGRAMMING RIGHT?
# So instead I'll iterate *existing* load commands, find a dyld_command, copy it
# and modify this copy. This existing command is said to be fully initialized.
lc = None
cmd = None
for (command, internal_cmd, data) in header.commands:
if (command.cmd == LC_LOAD_DYLIB) and isinstance(internal_cmd, dylib_command):
lc = deepcopy(command)
cmd = deepcopy(internal_cmd)
break
if not lc or not cmd:
raise Exception("Invalid Mach-O file. I mean, there must be at least one LC_LOAD_DYLIB load command.")
return None
# Well, now we just replace everything with our own stuff
cmd.timestamp = 0
cmd.current_version = cmd.compatibility_version = 0x1000
# Since we store the library's path just after the load command itself, we need to find out it's offset.
base = sizeof(load_command) + sizeof(dylib_command)
# `name` is rather bad name for this property: actually it means a path string offset
cmd.name = base
# Also the whole thing must be aligned by 4 bytes on 32-bit arches and by 8 bytes on 64-bit arches
align = 4 if header.header.magic == MH_MAGIC else 8
aligned_name = libary_install_name + (b'\x00' * (align - (len(libary_install_name) % align)))
# So now we finally can say what size this load_command is
lc.cmdsize = base + len(aligned_name)
return (lc, cmd, aligned_name)
def testBasic(self):
for endian in '><':
kw = dict(_endian_=endian)
MYSTRUCTURE = b'\x00\x11\x22\x33\xFF'
for fn, args in [
('from_str', (MYSTRUCTURE, )),
('from_mmap', (MYSTRUCTURE, 0)),
('from_fileobj', (BytesIO(MYSTRUCTURE), )),
]:
myStructure = getattr(MyStructure, fn)(*args, **kw)
if endian == '>':
self.assertEqual(myStructure.foo, 0x00112233)
else:
self.assertEqual(myStructure.foo, 0x33221100)
self.assertEqual(myStructure.bar, 0xFF)
self.assertEqual(myStructure.to_str(), MYSTRUCTURE)
MYFUNSTRUCTURE = b'!' + MYSTRUCTURE
for fn, args in [
('from_str', (MYFUNSTRUCTURE, )),
('from_mmap', (MYFUNSTRUCTURE, 0)),
('from_fileobj', (BytesIO(MYFUNSTRUCTURE), )),
]:
myFunStructure = getattr(MyFunStructure, fn)(*args, **kw)
self.assertEqual(myFunStructure.mystruct, myStructure)
self.assertEqual(myFunStructure.fun, b'!',
(myFunStructure.fun, b'!'))
self.assertEqual(myFunStructure.to_str(), MYFUNSTRUCTURE)
sio = BytesIO()
myFunStructure.to_fileobj(sio)
self.assertEqual(sio.getvalue(), MYFUNSTRUCTURE)
mm = mmap.mmap(-1, ptypes.sizeof(MyFunStructure) * 2)
mm[:] = b'\x00' * (ptypes.sizeof(MyFunStructure) * 2)
myFunStructure.to_mmap(mm, 0)
self.assertEqual(MyFunStructure.from_mmap(mm, 0, **kw),
myFunStructure)
self.assertEqual(mm[:ptypes.sizeof(MyFunStructure)],
MYFUNSTRUCTURE)
self.assertEqual(mm[ptypes.sizeof(MyFunStructure):],
b'\x00' * ptypes.sizeof(MyFunStructure))
myFunStructure.to_mmap(mm, ptypes.sizeof(MyFunStructure))
self.assertEqual(mm[:], MYFUNSTRUCTURE + MYFUNSTRUCTURE)
self.assertEqual(
MyFunStructure.from_mmap(mm, ptypes.sizeof(MyFunStructure),
**kw), myFunStructure)
def testBasic(self):
for endian in '><':
kw = dict(_endian_=endian)
MYSTRUCTURE = b'\x00\x11\x22\x33\xFF'
for fn, args in [
('from_str', (MYSTRUCTURE,)),
('from_mmap', (MYSTRUCTURE, 0)),
('from_fileobj', (BytesIO(MYSTRUCTURE),)),
]:
myStructure = getattr(MyStructure, fn)(*args, **kw)
if endian == '>':
self.assertEqual(myStructure.foo, 0x00112233)
else:
self.assertEqual( myStructure.foo, 0x33221100)
self.assertEqual(myStructure.bar, 0xFF)
self.assertEqual(myStructure.to_str(), MYSTRUCTURE)
MYFUNSTRUCTURE = b'!' + MYSTRUCTURE
for fn, args in [
('from_str', (MYFUNSTRUCTURE,)),
('from_mmap', (MYFUNSTRUCTURE, 0)),
('from_fileobj', (BytesIO(MYFUNSTRUCTURE),)),
]:
myFunStructure = getattr(MyFunStructure, fn)(*args, **kw)
self.assertEqual(myFunStructure.mystruct, myStructure)
self.assertEqual(myFunStructure.fun, b'!', (myFunStructure.fun, b'!'))
self.assertEqual(myFunStructure.to_str(), MYFUNSTRUCTURE)
sio = BytesIO()
myFunStructure.to_fileobj(sio)
self.assertEqual(sio.getvalue(), MYFUNSTRUCTURE)
mm = mmap.mmap(-1, ptypes.sizeof(MyFunStructure) * 2)
mm[:] = b'\x00' * (ptypes.sizeof(MyFunStructure) * 2)
myFunStructure.to_mmap(mm, 0)
self.assertEqual(MyFunStructure.from_mmap(mm, 0, **kw), myFunStructure)
self.assertEqual(mm[:ptypes.sizeof(MyFunStructure)], MYFUNSTRUCTURE)
self.assertEqual(mm[ptypes.sizeof(MyFunStructure):], b'\x00' * ptypes.sizeof(MyFunStructure))
myFunStructure.to_mmap(mm, ptypes.sizeof(MyFunStructure))
self.assertEqual(mm[:], MYFUNSTRUCTURE + MYFUNSTRUCTURE)
self.assertEqual(MyFunStructure.from_mmap(mm, ptypes.sizeof(MyFunStructure), **kw), myFunStructure)
