Ethernet¶

class os_ken.lib.packet.ethernet.ethernet(dst='ff:ff:ff:ff:ff:ff', src='00:00:00:00:00:00', ethertype=2048)¶

Ethernet header encoder/decoder class.

An instance has the following attributes at least. MAC addresses are represented as a string like '08:60:6e:7f:74:e7'. __init__ takes the corresponding args in this order.

Attribute	Description	Example
dst	destination address	'ff:ff:ff:ff:ff:ff'
src	source address	'08:60:6e:7f:74:e7'
ethertype	ether type	0x0800

classmethod get_packet_type(type_)¶

Override method for the ethernet IEEE802.3 Length/Type field (self.ethertype).

If the value of Length/Type field is less than or equal to 1500 decimal(05DC hexadecimal), it means Length interpretation and be passed to the LLC sublayer.

classmethod parser(buf)¶

Decode a protocol header.

This method is used only when decoding a packet.

Decode a protocol header at offset 0 in bytearray buf. Returns the following three objects.

• An object to describe the decoded header.
• A packet_base.PacketBase subclass appropriate for the rest of the packet. None when the rest of the packet should be considered as raw payload.
• The rest of packet.

serialize(payload, prev)¶

Encode a protocol header.

This method is used only when encoding a packet.

Encode a protocol header. Returns a bytearray which contains the header.

payload is the rest of the packet which will immediately follow this header.

prev is a packet_base.PacketBase subclass for the outer protocol header. prev is None if the current header is the outer-most. For example, prev is ipv4 or ipv6 for tcp.serialize.