def _read_mode_ts(self, size, kind):
"""Read Time Stamp option.
Structure of Timestamp (TS) option [:rfc:`791`]::
+--------+--------+--------+--------+
|01000100| length | pointer|oflw|flg|
+--------+--------+--------+--------+
| internet address |
+--------+--------+--------+--------+
| timestamp |
+--------+--------+--------+--------+
| . |
.
.
Arguments:
size (int): length of option
kind (Literal[68]): option kind value (TS)
Returns:
DataType_Opt_TimeStamp: extracted Time Stamp option
Raises:
ProtocolError: If the option is malformed.
"""
if size > 40 or size < 4:
raise ProtocolError(f'{self.alias}: [OptNo {kind}] invalid format')
_tptr = self._read_unpack(1)
_oflg = self._read_binary(1)
_oflw = int(_oflg[:4], base=2)
_flag = int(_oflg[4:], base=2)
if _tptr < 5:
raise ProtocolError(f'{self.alias}: [OptNo {kind}] invalid format')
data = dict(
kind=kind,
type=self._read_opt_type(kind),
length=size,
pointer=_tptr,
overflow=_oflw,
flag=_flag,
)
endpoint = min(_tptr, size)
if _flag == 0:
if (size - 4) % 4 != 0:
raise ProtocolError(
f'{self.alias}: [OptNo {kind}] invalid format')
counter = 5
timestamp = list()
while counter < endpoint:
counter += 4
time = self._read_unpack(4, lilendian=True)
timestamp.append(datetime.datetime.fromtimestamp(time))
data['timestamp'] = timestamp or None
elif _flag in (1, 3):
if (size - 4) % 8 != 0:
raise ProtocolError(
f'{self.alias}: [OptNo {kind}] invalid format')
counter = 5
ipaddress = list() # pylint: disable=redefined-outer-name
timestamp = list()
while counter < endpoint:
counter += 8
ipaddress.append(self._read_ipv4_addr())
time = self._read_unpack(4, lilendian=True)
timestamp.append(datetime.datetime.fromtimestamp(time))
data['ip'] = tuple(ipaddress) or None
data['timestamp'] = tuple(timestamp) or None
else:
data['data'] = self._read_fileng(size - 4) or None
return data
def _read_mode_ts(self, size, kind):
"""Read Time Stamp option.
Positional arguments:
* size - int, length of option
* kind - int, 68 (TS)
Returns:
* dict -- extracted Time Stamp (TS) option
Structure of Timestamp (TS) option [RFC 791]:
+--------+--------+--------+--------+
|01000100| length | pointer|oflw|flg|
+--------+--------+--------+--------+
| internet address |
+--------+--------+--------+--------+
| timestamp |
+--------+--------+--------+--------+
| . |
.
.
Octets Bits Name Description
0 0 ip.ts.kind Kind (25)
0 0 ip.ts.type.copy Copied Flag (0)
0 1 ip.ts.type.class Option Class (0)
0 3 ip.ts.type.number Option Number (25)
1 8 ip.ts.length Length (≤40)
2 16 ip.ts.pointer Pointer (≥5)
3 24 ip.ts.overflow Overflow Octets
3 28 ip.ts.flag Flag
4 32 ip.ts.ip Internet Address
8 64 ip.ts.timestamp Timestamp
"""
if size > 40 or size < 4:
raise ProtocolError(f'{self.alias}: [Optno {kind}] invalid format')
_tptr = self._read_unpack(1)
_oflg = self._read_binary(1)
_oflw = int(_oflg[:4], base=2)
_flag = int(_oflg[4:], base=2)
if _tptr < 5:
raise ProtocolError(f'{self.alias}: [Optno {kind}] invalid format')
data = dict(
kind=kind,
type=self._read_opt_type(kind),
length=size,
pointer=_tptr,
overflow=_oflw,
flag=_flag,
)
endpoint = min(_tptr, size)
if _flag == 0:
if (size - 4) % 4 != 0:
raise ProtocolError(
f'{self.alias}: [Optno {kind}] invalid format')
counter = 5
timestamp = list()
while counter < endpoint:
counter += 4
time = self._read_unpack(4, lilendian=True)
timestamp.append(datetime.datetime.fromtimestamp(time))
data['timestamp'] = timestamp or None
elif _flag == 1 or _flag == 3:
if (size - 4) % 8 != 0:
raise ProtocolError(
f'{self.alias}: [Optno {kind}] invalid format')
counter = 5
ipaddress = list()
timestamp = list()
while counter < endpoint:
counter += 8
ipaddress.append(self._read_ipv4_addr())
time = self._read_unpack(4, lilendian=True)
timestamp.append(datetime.datetime.fromtimestamp(time))
data['ip'] = ipaddress or None
data['timestamp'] = timestamp or None
else:
data['data'] = self._read_fileng(size - 4) or None
return data