Source code for hwtLib.types.net.ethernet

from typing import Union, List

from hwt.hdl.types.bits import HBits
from hwt.hdl.types.struct import HStruct
from hwt.hdl.types.defs import BIT


vlan_t = HBits(12)
eth_mac_t = HBits(6 * 8)

eth_syncword = 0b1010101010101010101010101010101010101010101010101010101010101011

EthPreamble_t = HStruct(
    (HBits(7 * 8), "preambule"),
    (HBits(8), "startOfFrameDelimiter"),
    name="EthPreamble_t"
)
EthType_t = HBits(2 * 8)
Eth2Header_t = HStruct(
    (eth_mac_t, "dst"),
    (eth_mac_t, "src"),
    (EthType_t, "type"),  # :see: :class:`~.ETHER_TYPE`
    name="Eth2Header_t"
)

Tag802_1q = HStruct( # inserted before Eth2Header_t.type, :see: :attr:`ETHER_TYPE.VLAN_1Q`
    (EthType_t, "tpid"), # Tag Protocol identifier (ETHER_TYPE)
    (HBits(16), "tci")
)
Tag802_1q_tci_t = HStruct(
 (HBits(3), "pcp"), # Priority Code Point
 (BIT, "dei"), # Drop Eligle Indicator
 (HBits(12), "vid"), # VLAN ID
)

Eth802_1qHeader_t = HStruct(
    (eth_mac_t, "dst"),
    (eth_mac_t, "src"),
    (Tag802_1q, "tag"),
    (EthType_t, "type"),
    name="Eth802_1qHeader_t"
)




class ETHER_TYPE():
    IPv4 = 0x0800
    ARP = 0x0806
    # wake on LAN
    WoL = 0x0842
    IPX = 0x8137
    IPX_b = 0x8138
    QNX_qnet = 0x8204
    IPv6 = 0x86DD
    MPLS_unicast = 0x8847
    MPLS_multicast = 0x8848
    VLAN_1Q = 0x8100
    VLAN_1AD = 0x88A8





def eth_addr_format(mac: List[Union[int, str]]):
    assert len(mac) == 6
    macStr = "%.2x:%.2x:%.2x:%.2x:%.2x:%.2x" % tuple(
        ord(x) if isinstance(x, str) else int(x)
        for x in mac)
    return macStr





def eth_addr_parse(macStr:str):
    """
    :return convert Ethernet MAC address to bytes, in big endian format
        (the first byte is the first one in text form and it has the highest importance)
    """
    splited = macStr.split(":")
    splited = map(lambda num: int(num, 16).to_bytes(1, byteorder='big'), splited)
    return b"".join(splited)





def eth_protocol_efficiency(PACKET_SIZE: int):
    """
    Return the efficiency (1.-overhead) of ethernet for specified packet size in octets 
    """
    return (PACKET_SIZE / (PACKET_SIZE + 7 + 1 + 12  # preambule + SFD + IPG
                           ))