def _serialize_frame(self, opcode, payload=b'', fin=True):
rsv = (False, False, False)
for extension in reversed(self.extensions):
if not extension.enabled():
continue
rsv, payload = extension.frame_outbound(
self, opcode, rsv, payload, fin)
fin_rsv = 0
for bit in rsv:
fin_rsv <<= 1
fin_rsv |= int(bit)
fin_rsv |= (int(fin) << 3)
fin_rsv_opcode = fin_rsv << 4 | opcode
payload_length = len(payload)
quad_payload = False
if payload_length <= MAX_PAYLOAD_NORMAL:
first_payload = payload_length
second_payload = None
elif payload_length <= MAX_PAYLOAD_TWO_BYTE:
first_payload = PAYLOAD_LENGTH_TWO_BYTE
second_payload = payload_length
else:
first_payload = PAYLOAD_LENGTH_EIGHT_BYTE
second_payload = payload_length
quad_payload = True
if self.client:
first_payload |= 1 << 7
header = bytes([fin_rsv_opcode, first_payload])
if second_payload is not None:
if opcode.iscontrol():
raise ValueError("payload too long for control frame")
if quad_payload:
header += struct.pack('!Q', second_payload)
else:
header += struct.pack('!H', second_payload)
if self.client:
# "The masking key is a 32-bit value chosen at random by the
# client. When preparing a masked frame, the client MUST pick a
# fresh masking key from the set of allowed 32-bit values. The
# masking key needs to be unpredictable; thus, the masking key
# MUST be derived from a strong source of entropy, and the masking
# key for a given frame MUST NOT make it simple for a server/proxy
# to predict the masking key for a subsequent frame. The
# unpredictability of the masking key is essential to prevent
# authors of malicious applications from selecting the bytes that
# appear on the wire."
# -- https://tools.ietf.org/html/rfc6455#section-5.3
masking_key = os.urandom(4)
masker = XorMaskerSimple(masking_key)
return header + masking_key + masker.process(payload)
else:
return header + payload
def _serialize_frame(self, opcode, payload=b'', fin=True):
rsv = RsvBits(False, False, False)
for extension in reversed(self.extensions):
rsv, payload = extension.frame_outbound(self, opcode, rsv, payload,
fin)
fin_rsv_opcode = self._make_fin_rsv_opcode(fin, rsv, opcode)
payload_length = len(payload)
quad_payload = False
if payload_length <= MAX_PAYLOAD_NORMAL:
first_payload = payload_length
second_payload = None
elif payload_length <= MAX_PAYLOAD_TWO_BYTE:
first_payload = PAYLOAD_LENGTH_TWO_BYTE
second_payload = payload_length
else:
first_payload = PAYLOAD_LENGTH_EIGHT_BYTE
second_payload = payload_length
quad_payload = True
if self.client:
first_payload |= 1 << 7
header = bytearray([fin_rsv_opcode, first_payload])
if second_payload is not None:
if opcode.iscontrol():
raise ValueError("payload too long for control frame")
if quad_payload:
header += bytearray(struct.pack('!Q', second_payload))
else:
header += bytearray(struct.pack('!H', second_payload))
if self.client:
# "The masking key is a 32-bit value chosen at random by the
# client. When preparing a masked frame, the client MUST pick a
# fresh masking key from the set of allowed 32-bit values. The
# masking key needs to be unpredictable; thus, the masking key
# MUST be derived from a strong source of entropy, and the masking
# key for a given frame MUST NOT make it simple for a server/proxy
# to predict the masking key for a subsequent frame. The
# unpredictability of the masking key is essential to prevent
# authors of malicious applications from selecting the bytes that
# appear on the wire."
# -- https://tools.ietf.org/html/rfc6455#section-5.3
masking_key = os.urandom(4)
masker = XorMaskerSimple(masking_key)
return header + masking_key + masker.process(payload)
return header + payload
def _apply_mask(self, mask, data):
masker = XorMaskerSimple(mask)
return masker.process(data)
def mask(self, data):
if self.masking_key:
masker = XorMaskerSimple(self.masking_key)
return masker.process(data)
return data
def test_xormasker():
masker = XorMaskerSimple(b'\xf0\xf0\x0f\x0f')
assert b'\xf0\xf0\x0f\x0f\xf0\xf0' == masker.process(b'\x00'*6)
assert masker.pointer() == 6
assert b'\x0f\x0f\xf0\xf0\x0f\x0f' == masker.process(b'\x00'*6)
assert masker.pointer() == 12
def _apply_mask(self, mask, data):
masker = XorMaskerSimple(mask)
return masker.process(data)
def mask(self, data):
if self.masking_key:
masker = XorMaskerSimple(self.masking_key)
return masker.process(data)
return data
