def phrx_ip4(self, ip4_packet_rx):
""" Handle inbound IP packets """
self.logger.debug(f"{ip4_packet_rx.tracker} - {ip4_packet_rx}")
# Check if received packet has been sent to us directly or by unicast/broadcast, allow any destination if no unicast address is configured (for DHCP client)
if self.stack_ip4_unicast and ip4_packet_rx.ip4_dst not in {*self.stack_ip4_unicast, *self.stack_ip4_multicast, *self.stack_ip4_broadcast}:
self.logger.debug(f"{ip4_packet_rx.tracker} - IP packet not destined for this stack, droping")
return
# Validate IP header checksum
if not ip4_packet_rx.validate_cksum():
self.logger.debug(f"{ip4_packet_rx.tracker} - IP packet has invalid checksum, droping")
return
# Check if packet is a fragment, and if so process it accrdingly
ip4_packet_rx = handle_ip4_fragmentation(ip4_packet_rx)
if not ip4_packet_rx:
return
if ip4_packet_rx.ip4_proto == ps_ip4.IP4_PROTO_ICMP4 and ps_icmp4.preliminary_sanity_check(ip4_packet_rx.raw_data, ip4_packet_rx.tracker, self.logger):
self.phrx_icmp4(ip4_packet_rx, ps_icmp4.Icmp4Packet(ip4_packet_rx))
return
if ip4_packet_rx.ip4_proto == ps_ip4.IP4_PROTO_UDP and ps_udp.preliminary_sanity_check(ip4_packet_rx.raw_data, ip4_packet_rx.tracker, self.logger):
self.phrx_udp(ip4_packet_rx, ps_udp.UdpPacket(ip4_packet_rx))
return
if ip4_packet_rx.ip4_proto == ps_ip4.IP4_PROTO_TCP and ps_tcp.preliminary_sanity_check(ip4_packet_rx.raw_data, ip4_packet_rx.tracker, self.logger):
self.phrx_tcp(ip4_packet_rx, ps_tcp.TcpPacket(ip4_packet_rx))
return
def phrx_ip6(self, ip6_packet_rx):
""" Handle inbound IP packets """
self.logger.debug(f"{ip6_packet_rx.tracker} - {ip6_packet_rx}")
# Check if received packet has been sent to us directly or by unicast or multicast
if ip6_packet_rx.ip6_dst not in {
*self.stack_ip6_unicast, *self.stack_ip6_multicast
}:
self.logger.debug(
f"{ip6_packet_rx.tracker} - IP packet not destined for this stack, droping"
)
return
if ip6_packet_rx.ip6_next == ps_ip6.IP6_NEXT_HEADER_ICMP6 and ps_icmp6.preliminary_sanity_check(
ip6_packet_rx.raw_data, ip6_packet_rx.tracker, self.logger):
self.phrx_icmp6(ip6_packet_rx, ps_icmp6.Icmp6Packet(ip6_packet_rx))
return
if ip6_packet_rx.ip6_next == ps_ip6.IP6_NEXT_HEADER_UDP and ps_udp.preliminary_sanity_check(
ip6_packet_rx.raw_data, ip6_packet_rx.tracker, self.logger):
self.phrx_udp(ip6_packet_rx, ps_udp.UdpPacket(ip6_packet_rx))
return
if ip6_packet_rx.ip6_next == ps_ip6.IP6_NEXT_HEADER_TCP and ps_tcp.preliminary_sanity_check(
ip6_packet_rx.raw_data, ip6_packet_rx.tracker, self.logger):
self.phrx_tcp(ip6_packet_rx, ps_tcp.TcpPacket(ip6_packet_rx))
return
def phrx_ip6(self, ip6_packet_rx):
""" Handle inbound IP packets """
# Validate IPv6 packet sanity
if ip6_packet_rx.sanity_check_failed:
return
self.logger.debug(f"{ip6_packet_rx.tracker} - {ip6_packet_rx}")
# Check if received packet has been sent to us directly or by unicast or multicast
if ip6_packet_rx.ip6_dst not in {*self.ip6_unicast, *self.ip6_multicast}:
self.logger.debug(
f"{ip6_packet_rx.tracker} - IP packet not destined for this stack, droping"
)
return
if ip6_packet_rx.ip6_next == ps_ip6.IP6_NEXT_HEADER_ICMP6:
self.phrx_icmp6(ip6_packet_rx, ps_icmp6.Icmp6Packet(ip6_packet_rx))
return
if ip6_packet_rx.ip6_next == ps_ip6.IP6_NEXT_HEADER_UDP:
self.phrx_udp(ip6_packet_rx, ps_udp.UdpPacket(ip6_packet_rx))
return
if ip6_packet_rx.ip6_next == ps_ip6.IP6_NEXT_HEADER_TCP:
self.phrx_tcp(ip6_packet_rx, ps_tcp.TcpPacket(ip6_packet_rx))
return
def main():
while True:
raw_packet_rx = raw_socket.recv(2048)
ether_packet_rx = ps_ether.EtherPacket(raw_packet_rx)
if ether_packet_rx.ether_type == ps_ether.ETHER_TYPE_ARP:
arp_packet_rx = ps_arp.ArpPacket(ether_packet_rx)
print("-" * 160)
print(ether_packet_rx)
print(arp_packet_rx)
print("-" * 160)
continue
if ether_packet_rx.ether_type == ps_ether.ETHER_TYPE_IP6:
ipv6_packet_rx = ps_ipv6.Ip6Packet(ether_packet_rx)
if ipv6_packet_rx.ipv6_next == ps_ipv6.IP6_NEXT_HEADER_ICMP6:
icmpv6_packet_rx = ps_icmpv6.Icmp6Packet(ipv6_packet_rx)
print("-" * 160)
print(ether_packet_rx)
print(ipv6_packet_rx)
print(icmpv6_packet_rx)
print("-" * 160)
continue
print("-" * 160)
print(ether_packet_rx)
print(ipv6_packet_rx)
continue
if ether_packet_rx.ether_type == ps_ether.ETHER_TYPE_IP6:
ipv4_packet_rx = ps_ipv4.Ip4Packet(ether_packet_rx)
if ipv4_packet_rx.ipv4_proto == ps_ipv4.IP4_PROTO_ICMP4:
icmpv4_packet_rx = ps_icmpv4.Icmp4Packet(ipv4_packet_rx)
print("-" * 160)
print(ether_packet_rx)
print(ipv4_packet_rx)
print(icmpv4_packet_rx)
print("-" * 160)
continue
if ipv4_packet_rx.ipv4_proto == ps_ipv4.IP4_PROTO_UDP:
udp_packet_rx = ps_udp.UdpPacket(ipv4_packet_rx)
print("-" * 160)
print(ether_packet_rx)
print(ipv4_packet_rx)
print(udp_packet_rx)
print("-" * 160)
continue
if ipv4_packet_rx.ipv4_proto == ps_ipv4.IP4_PROTO_TCP:
tcp_packet_rx = ps_tcp.TcpPacket(ipv4_packet_rx)
if 22 in {tcp_packet_rx.tcp_dport, tcp_packet_rx.tcp_sport}:
continue
print("-" * 160)
print(ether_packet_rx)
print(ipv4_packet_rx)
print(tcp_packet_rx)
print("-" * 160)
continue
print("-" * 160)
print(ether_packet_rx)
print(ipv4_packet_rx)
print("-" * 160)
continue
print("-" * 160)
print(ether_packet_rx)