test_mac.py

from scapy.layers.l2 import Ether, ARP
from pcap_anonymize.layers.mac import (
    get_ig_bit, get_ul_bit,
    anonymize_mac,
    anonymize_ether,
    anonymize_arp,
    anonymize_dhcp
)


### TEST CONSTANTS ###

mac_multicast = "01:00:00:00:00:00"
mac_laa = "02:00:00:00:00:00"
mac_uaa = "00:11:22:33:44:55"


### TEST FUNCTIONS ###

def test_get_ig_bit() -> None:
    """
    Test the function `get_ig_bit`.
    """
    assert get_ig_bit("00:00:00:00:00:00") == 0b00000000
    assert get_ig_bit("01:00:00:00:00:00") == 0b00000001
    assert get_ig_bit("12:34:56:78:9a:bc") == 0b00000000


def test_get_ul_bit() -> None:
    """
    Test the function `get_ul_bit`.
    """
    assert get_ul_bit("00:00:00:00:00:00") == 0b00000000
    assert get_ul_bit("02:00:00:00:00:00") == 0b00000010
    assert get_ul_bit("12:34:56:78:9a:bc") == 0b00000010


def test_anonymize_mac_multicast() -> None:
    """
    Test the function `anonymize_mac`
    with a multicast MAC address.
    The MAC address should not be anonymized.
    """
    assert anonymize_mac(mac_multicast) == mac_multicast


def test_anonymize_mac_laa() -> None:
    """
    Test the function `anonymize_mac`
    with a locally administered MAC address.
    All bits should be anonymized except the I/G and U/L bits.
    """
    mac_laa_anon = anonymize_mac(mac_laa)
    assert mac_laa_anon != mac_laa
    # Verify I/G and U/L bits
    assert get_ig_bit(mac_laa) == get_ig_bit(mac_laa_anon)
    assert get_ul_bit(mac_laa) == get_ul_bit(mac_laa_anon)


def test_anonymize_mac_uaa() -> None:
    """
    Test the function `anonymize_mac`
    with an universally administered MAC address.
    The 3 first bytes (vendor's OUI) should be kept,
    and the 3 last bytes should be anonymized.
    """
    mac_uaa_anon = anonymize_mac(mac_uaa)
    assert mac_uaa_anon.startswith(mac_uaa[:8])  # Vendor's OUI is kept
    assert mac_uaa_anon[10:] != mac_uaa[10:]     # Last 3 bytes are anonymized


def test_anonymize_ether_multicast() -> None:
    """
    Test the function `anonymize_ether`,
    with multicast addresses.
    """
    ether_multicast = Ether(src=mac_multicast, dst=mac_multicast)
    anonymize_ether(ether_multicast)
    assert ether_multicast.src == mac_multicast
    assert ether_multicast.dst == mac_multicast


def test_anonymize_ether_laa() -> None:
    """
    Test the function `anonymize_ether`,
    with locally administered addresses.
    """
    ether_laa = Ether(src=mac_laa, dst=mac_laa)
    anonymize_ether(ether_laa)
    assert ether_laa.src != mac_laa
    assert get_ig_bit(ether_laa.src) == get_ig_bit(mac_laa)
    assert get_ul_bit(ether_laa.src) == get_ul_bit(mac_laa)
    assert ether_laa.dst != mac_laa
    assert get_ig_bit(ether_laa.dst) == get_ig_bit(mac_laa)
    assert get_ul_bit(ether_laa.dst) == get_ul_bit(mac_laa)


def test_anonymize_ether_uaa() -> None:
    """
    Test the function `anonymize_ether`,
    with universally administered addresses.
    """
    ether_laa = Ether(src=mac_uaa, dst=mac_uaa)
    anonymize_ether(ether_laa)
    assert ether_laa.src.startswith(mac_uaa[:8])
    assert ether_laa.src[10:] != mac_uaa[10:]
    assert ether_laa.dst.startswith(mac_uaa[:8])
    assert ether_laa.dst[10:] != mac_uaa[10:]