UDP - User Datagram Protocol¶

pcapkit.protocols.transport.udp contains UDP only, which implements extractor for User Datagram Protocol (UDP) [*], whose structure is described as below:

Octets	Bits	Name	Description
0	0	`udp.srcport`	Source Port
2	16	`udp.dstport`	Destination Port
4	32	`udp.len`	Length (header includes)
6	48	`udp.checksum`	Checksum

class pcapkit.protocols.transport.udp.UDP(file=None, length=None, **kwargs)[source]¶

Bases: Transport[UDP, UDP]

This class implements User Datagram Protocol.

This class currently supports parsing of the following protocols, which are registered in the self.__proto__ attribute:

Port Number	Protocol
80	`pcapkit.protocols.application.http.HTTP`

property name: Literal['User Datagram Protocol']¶: Name of current protocol.

property length: Literal[8]¶: Header length of current protocol.

property src: AppType¶: Source port.

property dst: AppType¶: Destination port.

read(length=None, **kwargs)[source]¶

Read User Datagram Protocol (UDP).

Structure of UDP header [RFC 768]:

 0      7 8     15 16    23 24    31
+--------+--------+--------+--------+
|     Source      |   Destination   |
|      Port       |      Port       |
+--------+--------+--------+--------+
|                 |                 |
|     Length      |    Checksum     |
+--------+--------+--------+--------+
|
|          data octets ...
+---------------- ...

Parameters:

length (Optional[int]) – Length of packet data.
**kwargs (Any) – Arbitrary keyword arguments.

Return type:

UDP

Returns:

Parsed packet data.

make(srcport=0, dstport=0, checksum=b'\\x00\\x00', payload=b'', **kwargs)[source]¶

Make (construct) packet data.

Parameters:

srcport (AppType | int) – Source port.
dstport (AppType | int) – Destination port.
checksum (bytes) – Checksum.
payload (bytes | Schema | ProtocolBase) – Payload data.
**kwargs (Any) – Arbitrary keyword arguments.

Return type:

UDP

Returns:

Constructed packet data.

classmethod _make_data(data)[source]¶

Create key-value pairs from data for protocol construction.

Parameters:: data (UDP) – protocol data
Return type:: dict[str, Any]
Returns:: Key-value pairs for protocol construction.

__proto__: DefaultDict[int, ModuleDescriptor[Protocol] | Type[Protocol]]¶

Protocol index mapping for decoding next layer, c.f. self._decode_next_layer & self._import_next_layer.

Type:: DefaultDict[int, ModuleDescriptor[Protocol] | Type[Protocol]]

classmethod __index__()[source]¶

Numeral registry index of the protocol.

Return type:: TransType
Returns:: Numeral registry index of the protocol in IANA.

Header Schemas¶

class pcapkit.protocols.schema.transport.udp.UDP(dict_=None, **kwargs)[source]¶

Bases: Schema

Header schema for UDP packet.

srcport: Enum_AppType = <PortEnumField srcport>¶: Source port.

dstport: Enum_AppType = <PortEnumField dstport>¶: Destination port.

len: int = <UInt16Field len>¶: Length of UDP packet.

checksum: bytes = <BytesField checksum>¶: Checksum of UDP packet.

payload: bytes = <PayloadField payload>¶: Payload.

Data Models¶

class pcapkit.protocols.data.transport.udp.UDP(*args: VT, **kwargs: VT)[source]¶

Bases: Protocol

Data model for UDP protocol.

srcport: AppType¶: Source port.

dstport: AppType¶: Destination port.

len: int¶: Length (header includes).

checksum: bytes¶: Checksum.

Footnotes