mac_address_ranges.py 文件源码

def _to_mac_range(val):
    cidr_parts = val.split("/")
    prefix = cidr_parts[0]

    # FIXME(anyone): replace is slow, but this doesn't really
    #               get called ever. Fix maybe?
    prefix = prefix.replace(':', '')
    prefix = prefix.replace('-', '')
    prefix_length = len(prefix)
    if prefix_length < 6 or prefix_length > 12:
        raise q_exc.InvalidMacAddressRange(cidr=val)

    diff = 12 - len(prefix)
    if len(cidr_parts) > 1:
        mask = int(cidr_parts[1])
    else:
        mask = 48 - diff * 4
    mask_size = 1 << (48 - mask)
    prefix = "%s%s" % (prefix, "0" * diff)
    try:
        cidr = "%s/%s" % (str(netaddr.EUI(prefix)).replace("-", ":"), mask)
    except netaddr.AddrFormatError:
        raise q_exc.InvalidMacAddressRange(cidr=val)
    prefix_int = int(prefix, base=16)
    return cidr, prefix_int, prefix_int + mask_size