for tag_code, tag in extract_tags(content)
if tag_code == 82)
p = code_tag.index(b'\0', 4) + 1
+ code_reader = io.BytesIO(code_tag[p:])
# Parse ABC (AVM2 ByteCode)
- def read_int(data=None, pos=None):
- if hasattr(data, 'read'):
- assert pos is None
-
- res = 0
- shift = 0
- for _ in range(5):
- buf = data.read(1)
- assert len(buf) == 1
- b = struct.unpack('<B', buf)[0]
- res = res | ((b & 0x7f) << shift)
- if b & 0x80 == 0:
- break
- shift += 7
- return res
-
- if data is None:
- data = code_tag
- if pos is None:
- pos = p
+ def read_int(reader=None):
+ if reader is None:
+ reader = code_reader
res = 0
shift = 0
for _ in range(5):
- b = struct.unpack('<B', data[pos:pos+1])[0]
- pos += 1
+ buf = reader.read(1)
+ assert len(buf) == 1
+ b = struct.unpack('<B', buf)[0]
res = res | ((b & 0x7f) << shift)
if b & 0x80 == 0:
break
shift += 7
- return (res, pos)
- assert read_int(b'\x00', 0) == (0, 1)
- assert read_int(b'\x10', 0) == (16, 1)
- assert read_int(b'\x34', 0) == (0x34, 1)
- assert read_int(b'\xb4\x12', 0) == (0x12 * 0x80 + 0x34, 2)
- assert read_int(b'\xff\xff\xff\x00', 0) == (0x1fffff, 4)
-
- def u30(*args, **kwargs):
- res = read_int(*args, **kwargs)
- if isinstance(res, tuple):
- assert res[0] & 0xf0000000 == 0
- else:
- assert res & 0xf0000000 == 0
+ return res
+
+ def u30(reader=None):
+ res = read_int(reader)
+ assert res & 0xf0000000 == 0
return res
u32 = read_int
- def s32(data=None, pos=None):
- v, pos = read_int(data, pos)
+ def s32(reader=None):
+ v = read_int(reader)
if v & 0x80000000 != 0:
v = - ((v ^ 0xffffffff) + 1)
- return (v, pos)
- assert s32(b'\xff\xff\xff\xff\x0f', 0) == (-1, 5)
-
- def string():
- slen, p = u30()
- return (code_tag[p:p+slen].decode('utf-8'), p + slen)
-
- def read_byte(data=None, pos=None):
- if data is None:
- data = code_tag
- if pos is None:
- pos = p
- res = struct.unpack('<B', data[pos:pos+1])[0]
- return (res, pos + 1)
+ return v
+
+ def string(reader=None):
+ if reader is None:
+ reader = code_reader
+ slen = u30(reader)
+ resb = reader.read(slen)
+ assert len(resb) == slen
+ return resb.decode('utf-8')
+
+ def read_bytes(count, reader=None):
+ if reader is None:
+ reader = code_reader
+ resb = reader.read(count)
+ assert len(resb) == count
+ return resb
+
+ def read_byte(reader=None):
+ resb = read_bytes(1, reader=reader)
+ res = struct.unpack('<B', resb)[0]
+ return res
# minor_version + major_version
- p += 2 + 2
+ _ = read_bytes(4)
# Constant pool
- int_count, p = u30()
+ int_count = u30()
for _c in range(1, int_count):
- _, p = s32()
- uint_count, p = u30()
+ _ = s32()
+ uint_count = u30()
for _c in range(1, uint_count):
- _, p = u32()
- double_count, p = u30()
- p += (double_count-1) * 8
- string_count, p = u30()
+ _ = u32()
+ double_count = u30()
+ _ = read_bytes((double_count-1) * 8)
+ string_count = u30()
constant_strings = [u'']
for _c in range(1, string_count):
- s, p = string()
+ s = string()
constant_strings.append(s)
- namespace_count, p = u30()
+ namespace_count = u30()
for _c in range(1, namespace_count):
- p += 1 # kind
- _, p = u30() # name
- ns_set_count, p = u30()
+ _ = read_bytes(1) # kind
+ _ = u30() # name
+ ns_set_count = u30()
for _c in range(1, ns_set_count):
- count, p = u30()
+ count = u30()
for _c2 in range(count):
- _, p = u30()
- multiname_count, p = u30()
+ _ = u30()
+ multiname_count = u30()
MULTINAME_SIZES = {
0x07: 2, # QName
0x0d: 2, # QNameA
}
multinames = [u'']
for _c in range(1, multiname_count):
- kind, p = u30()
+ kind = u30()
assert kind in MULTINAME_SIZES, u'Invalid multiname kind %r' % kind
if kind == 0x07:
- namespace_idx, p = u30()
- name_idx, p = u30()
+ namespace_idx = u30()
+ name_idx = u30()
multinames.append(constant_strings[name_idx])
else:
multinames.append('[MULTINAME kind: %d]' % kind)
for _c2 in range(MULTINAME_SIZES[kind]):
- _, p = u30()
+ _ = u30()
# Methods
- method_count, p = u30()
+ method_count = u30()
MethodInfo = collections.namedtuple(
'MethodInfo',
['NEED_ARGUMENTS', 'NEED_REST'])
method_infos = []
for method_id in range(method_count):
- param_count, p = u30()
- _, p = u30() # return type
+ param_count = u30()
+ _ = u30() # return type
for _ in range(param_count):
- _, p = u30() # param type
- _, p = u30() # name index (always 0 for youtube)
- flags, p = read_byte()
+ _ = u30() # param type
+ _ = u30() # name index (always 0 for youtube)
+ flags = read_byte()
if flags & 0x08 != 0:
# Options present
- option_count, p = u30()
+ option_count = u30()
for c in range(option_count):
- _, p = u30() # val
- p += 1 # kind
+ _ = u30() # val
+ _ = read_bytes(1) # kind
if flags & 0x80 != 0:
# Param names present
for _ in range(param_count):
- _, p = u30() # param name
+ _ = u30() # param name
mi = MethodInfo(flags & 0x01 != 0, flags & 0x04 != 0)
method_infos.append(mi)
# Metadata
- metadata_count, p = u30()
+ metadata_count = u30()
for _c in range(metadata_count):
- _, p = u30() # name
- item_count, p = u30()
+ _ = u30() # name
+ item_count = u30()
for _c2 in range(item_count):
- _, p = u30() # key
- _, p = u30() # value
-
- def parse_traits_info(pos=None):
- if pos is None:
- pos = p
- trait_name_idx, pos = u30(pos=pos)
- kind_full, pos = read_byte(pos=pos)
+ _ = u30() # key
+ _ = u30() # value
+
+ def parse_traits_info():
+ trait_name_idx = u30()
+ kind_full = read_byte()
kind = kind_full & 0x0f
attrs = kind_full >> 4
methods = {}
if kind in [0x00, 0x06]: # Slot or Const
- _, pos = u30(pos=pos) # Slot id
- type_name_idx, pos = u30(pos=pos)
- vindex, pos = u30(pos=pos)
+ _ = u30() # Slot id
+ type_name_idx = u30()
+ vindex = u30()
if vindex != 0:
- _, pos = read_byte(pos=pos) # vkind
+ _ = read_byte() # vkind
elif kind in [0x01, 0x02, 0x03]: # Method / Getter / Setter
- _, pos = u30(pos=pos) # disp_id
- method_idx, pos = u30(pos=pos)
+ _ = u30() # disp_id
+ method_idx = u30()
methods[multinames[trait_name_idx]] = method_idx
elif kind == 0x04: # Class
- _, pos = u30(pos=pos) # slot_id
- _, pos = u30(pos=pos) # classi
+ _ = u30() # slot_id
+ _ = u30() # classi
elif kind == 0x05: # Function
- _, pos = u30(pos=pos) # slot_id
- function_idx, pos = u30(pos=pos)
+ _ = u30() # slot_id
+ function_idx = u30()
methods[function_idx] = multinames[trait_name_idx]
else:
raise ExtractorError(u'Unsupported trait kind %d' % kind)
if attrs & 0x4 != 0: # Metadata present
- metadata_count, pos = u30(pos=pos)
+ metadata_count = u30()
for _c3 in range(metadata_count):
- _, pos = u30(pos=pos)
+ _ = u30()
- return (methods, pos)
+ return methods
# Classes
TARGET_CLASSNAME = u'SignatureDecipher'
searched_idx = multinames.index(TARGET_CLASSNAME)
searched_class_id = None
- class_count, p = u30()
+ class_count = u30()
for class_id in range(class_count):
- name_idx, p = u30()
+ name_idx = u30()
if name_idx == searched_idx:
# We found the class we're looking for!
searched_class_id = class_id
- _, p = u30() # super_name idx
- flags, p = read_byte()
+ _ = u30() # super_name idx
+ flags = read_byte()
if flags & 0x08 != 0: # Protected namespace is present
- protected_ns_idx, p = u30()
- intrf_count, p = u30()
+ protected_ns_idx = u30()
+ intrf_count = u30()
for _c2 in range(intrf_count):
- _, p = u30()
- _, p = u30() # iinit
- trait_count, p = u30()
+ _ = u30()
+ _ = u30() # iinit
+ trait_count = u30()
for _c2 in range(trait_count):
- _, p = parse_traits_info()
+ _ = parse_traits_info()
if searched_class_id is None:
raise ExtractorError(u'Target class %r not found' %
method_names = {}
method_idxs = {}
for class_id in range(class_count):
- _, p = u30() # cinit
- trait_count, p = u30()
+ _ = u30() # cinit
+ trait_count = u30()
for _c2 in range(trait_count):
- trait_methods, p = parse_traits_info()
+ trait_methods = parse_traits_info()
if class_id == searched_class_id:
method_names.update(trait_methods.items())
method_idxs.update(dict(
for name, idx in trait_methods.items()))
# Scripts
- script_count, p = u30()
+ script_count = u30()
for _c in range(script_count):
- _, p = u30() # init
- trait_count, p = u30()
+ _ = u30() # init
+ trait_count = u30()
for _c2 in range(trait_count):
- _, p = parse_traits_info()
+ _ = parse_traits_info()
# Method bodies
- method_body_count, p = u30()
+ method_body_count = u30()
Method = collections.namedtuple('Method', ['code', 'local_count'])
methods = {}
for _c in range(method_body_count):
- method_idx, p = u30()
- max_stack, p = u30()
- local_count, p = u30()
- init_scope_depth, p = u30()
- max_scope_depth, p = u30()
- code_length, p = u30()
+ method_idx = u30()
+ max_stack = u30()
+ local_count = u30()
+ init_scope_depth = u30()
+ max_scope_depth = u30()
+ code_length = u30()
+ code = read_bytes(code_length)
if method_idx in method_idxs:
- m = Method(code_tag[p:p+code_length], local_count)
+ m = Method(code, local_count)
methods[method_idxs[method_idx]] = m
- p += code_length
- exception_count, p = u30()
+ exception_count = u30()
for _c2 in range(exception_count):
- _, p = u30() # from
- _, p = u30() # to
- _, p = u30() # target
- _, p = u30() # exc_type
- _, p = u30() # var_name
- trait_count, p = u30()
+ _ = u30() # from
+ _ = u30() # to
+ _ = u30() # target
+ _ = u30() # exc_type
+ _ = u30() # var_name
+ trait_count = u30()
for _c2 in range(trait_count):
- _, p = parse_traits_info()
+ _ = parse_traits_info()
- assert p == len(code_tag)
+ assert p + code_reader.tell() == len(code_tag)
assert len(methods) == len(method_idxs)
method_pyfunctions = {}
projects / youtube-dl / commitdiff