This function is designed to extract specific IPv6 elements from a PCAP packet.

extract_ipv6_information.py

import regex
from typing import Union, Dict

def extract_ipv6_information(packet) -> Union[Dict[str, Union[str, int]], None]:
    """
    Extracts specific IPv6 elements from a PCAP packet.

    :param packet: PCAP packet
    :return: A dictionary containing extracted IPv6 information or None if not an IPv6 packet
    :rtype: Union[dict, None]
    """
    try:
        if 'IPV6' in str(packet.layers):
            result = {
                'source_address': packet.ipv6.src,
                'destination_address': packet.ipv6.dst,
                'next_header_info': regex.findall(r'(Next Header:)\s(\w.+)\s(\W\d{0,3}\W)', str(packet.layers[1]))
            }

            if 'ICMPV6' in str(packet.layers):
                result['icmpv6_type'] = regex.search(r'(Type:)\s(\w.+)\s(\W\d{0,3}\W)', str(packet.layers[2]))
            elif 'TCP' in str(packet.layers) or 'UDP' in str(packet.layers):
                protocol = packet.transport_layer
                result['protocol'] = protocol
                result['source_port'] = packet[protocol].srcport
                result['destination_port'] = packet[protocol].dstport

            return result
    except AttributeError:
        pass

    return None