#2248 - Initial crack at getting ARP into a Service. Lots of refactoring has been done. It's a mess at the minute, but I can successfully send an ARP request so committing as a successful point in time

src/primaite/simulator/__init__.py

@@ -12,8 +12,8 @@ class _SimOutput:
         self._path: Path = (
             _PRIMAITE_ROOT.parent.parent / "simulation_output" / datetime.now().strftime("%Y-%m-%d_%H-%M-%S")
         )
-        self.save_pcap_logs: bool = False
-        self.save_sys_logs: bool = False
+        self.save_pcap_logs: bool = True
+        self.save_sys_logs: bool = True
 
     @property
     def path(self) -> Path:

src/primaite/simulator/network/hardware/base.py

@@ -18,7 +18,7 @@ from primaite.simulator.network.hardware.node_operating_state import NodeOperati
 from primaite.simulator.network.protocols.arp import ARPEntry, ARPPacket
 from primaite.simulator.network.transmission.data_link_layer import EthernetHeader, Frame
 from primaite.simulator.network.transmission.network_layer import ICMPPacket, ICMPType, IPPacket, IPProtocol
-from primaite.simulator.network.transmission.transport_layer import Port, TCPHeader
+from primaite.simulator.network.transmission.transport_layer import Port, TCPHeader, UDPHeader
 from primaite.simulator.system.applications.application import Application
 from primaite.simulator.system.core.packet_capture import PacketCapture
 from primaite.simulator.system.core.session_manager import SessionManager
@@ -617,6 +617,7 @@ class ARPCache:
         self.sys_log: "SysLog" = sys_log
         self.arp: Dict[IPv4Address, ARPEntry] = {}
         self.nics: Dict[str, "NIC"] = {}
+        self.node = None
 
     def show(self, markdown: bool = False):
         """Prints a table of ARC Cache."""
@@ -669,6 +670,36 @@ class ARPCache:
         if ip_address in self.arp:
             del self.arp[ip_address]
 
+    def get_default_gateway_mac_address(self) -> Optional[str]:
+        if self.arp.node.default_gateway:
+            return self.get_arp_cache_mac_address(self.arp.node.default_gateway)
+
+    def get_default_gateway_nic(self) -> Optional[NIC]:
+        if self.arp.node.default_gateway:
+            return self.get_arp_cache_nic(self.arp.node.default_gateway)
+
+    def _get_arp_cache_mac_address(
+        self, ip_address: IPv4Address, is_reattempt: bool = False, is_default_gateway_attempt: bool = False
+    ) -> Optional[str]:
+        arp_entry = self.arp.get(ip_address)
+
+        if arp_entry:
+            return arp_entry.mac_address
+        else:
+            if not is_reattempt:
+                self.send_arp_request(ip_address)
+                return self._get_arp_cache_mac_address(
+                    ip_address=ip_address, is_reattempt=True, is_default_gateway_attempt=is_default_gateway_attempt
+                )
+            else:
+                if self.node.default_gateway:
+                    if not is_default_gateway_attempt:
+                        self.send_arp_request(self.node.default_gateway)
+                        return self._get_arp_cache_mac_address(
+                            ip_address=self.node.default_gateway, is_reattempt=True, is_default_gateway_attempt=True
+                        )
+        return None
+
     def get_arp_cache_mac_address(self, ip_address: IPv4Address) -> Optional[str]:
         """
         Get the MAC address associated with an IP address.
@@ -676,9 +707,29 @@ class ARPCache:
         :param ip_address: The IP address to look up in the cache.
         :return: The MAC address associated with the IP address, or None if not found.
         """
+        return self._get_arp_cache_mac_address(ip_address)
+
+    def _get_arp_cache_nic(
+        self, ip_address: IPv4Address, is_reattempt: bool = False, is_default_gateway_attempt: bool = False
+    ) -> Optional[NIC]:
         arp_entry = self.arp.get(ip_address)
+
         if arp_entry:
-            return arp_entry.mac_address
+            return self.nics[arp_entry.nic_uuid]
+        else:
+            if not is_reattempt:
+                self.send_arp_request(ip_address)
+                return self._get_arp_cache_nic(
+                    ip_address=ip_address, is_reattempt=True, is_default_gateway_attempt=is_default_gateway_attempt
+                )
+            else:
+                if self.node.default_gateway:
+                    if not is_default_gateway_attempt:
+                        self.send_arp_request(self.node.default_gateway)
+                        return self._get_arp_cache_nic(
+                            ip_address=self.node.default_gateway, is_reattempt=True, is_default_gateway_attempt=True
+                        )
+        return None
 
     def get_arp_cache_nic(self, ip_address: IPv4Address) -> Optional[NIC]:
         """
@@ -687,10 +738,7 @@ class ARPCache:
         :param ip_address: The IP address to look up in the cache.
         :return: The NIC associated with the IP address, or None if not found.
         """
-        arp_entry = self.arp.get(ip_address)
-
-        if arp_entry:
-            return self.nics[arp_entry.nic_uuid]
+        return self._get_arp_cache_nic(ip_address)
 
     def clear_arp_cache(self):
         """Clear the entire ARP cache, removing all stored entries."""
@@ -721,12 +769,11 @@ class ARPCache:
                         use_nic = False
             if nic.enabled and use_nic:
                 self.sys_log.info(f"Sending ARP request from NIC {nic} for ip {target_ip_address}")
-                tcp_header = TCPHeader(src_port=Port.ARP, dst_port=Port.ARP)
+                udp_header = UDPHeader(src_port=Port.ARP, dst_port=Port.ARP)
 
                 # Network Layer
                 ip_packet = IPPacket(
-                    src_ip_address=nic.ip_address,
-                    dst_ip_address=target_ip_address,
+                    src_ip_address=nic.ip_address, dst_ip_address=target_ip_address, protocol=IPProtocol.UDP
                 )
                 # Data Link Layer
                 ethernet_header = EthernetHeader(src_mac_addr=nic.mac_address, dst_mac_addr="ff:ff:ff:ff:ff:ff")
@@ -735,7 +782,7 @@ class ARPCache:
                     sender_mac_addr=nic.mac_address,
                     target_ip_address=target_ip_address,
                 )
-                frame = Frame(ethernet=ethernet_header, ip=ip_packet, tcp=tcp_header, arp=arp_packet)
+                frame = Frame(ethernet=ethernet_header, ip=ip_packet, udp=udp_header, payload=arp_packet)
                 nic.send_frame(frame)
 
     def send_arp_reply(self, arp_reply: ARPPacket, from_nic: NIC):
@@ -888,25 +935,14 @@ class ICMP:
             was not found in the ARP cache.
         """
         nic = self.arp.get_arp_cache_nic(target_ip_address)
-        # TODO: Eventually this ARP request needs to be done elsewhere. It's not the responsibility of the
-        # ping function to handle ARP lookups
 
-        # Already tried once and cannot get ARP entry, stop trying
-        if sequence == -1:
-            if not nic:
-                return 4, None
-            else:
-                sequence = 0
-
-        # No existing ARP entry
         if not nic:
-            self.sys_log.info(f"No entry in ARP cache for {target_ip_address}")
-            self.arp.send_arp_request(target_ip_address)
-            return -1, None
+            return pings, None
 
         # ARP entry exists
         sequence += 1
         target_mac_address = self.arp.get_arp_cache_mac_address(target_ip_address)
+
         src_nic = self.arp.get_arp_cache_nic(target_ip_address)
         tcp_header = TCPHeader(src_port=Port.ARP, dst_port=Port.ARP)
 
@@ -1026,6 +1062,7 @@ class Node(SimComponent):
             )
         super().__init__(**kwargs)
         self.arp.nics = self.nics
+        self.arp.node = self
         self.session_manager.software_manager = self.software_manager
         self._install_system_software()
         self.set_original_state()
@@ -1407,7 +1444,9 @@ class Node(SimComponent):
                 self.sys_log.info("Pinging loopback address")
                 return any(nic.enabled for nic in self.nics.values())
             if self.operating_state == NodeOperatingState.ON:
-                self.sys_log.info(f"Pinging {target_ip_address}:")
+                output = f"Pinging {target_ip_address}:"
+                self.sys_log.info(output)
+                print(output)
                 sequence, identifier = 0, None
                 while sequence < pings:
                     sequence, identifier = self.icmp.ping(target_ip_address, sequence, identifier, pings)
@@ -1417,12 +1456,14 @@ class Node(SimComponent):
                     self.icmp.request_replies.pop(identifier)
                 else:
                     request_replies = 0
-                self.sys_log.info(
+                output = (
                     f"Ping statistics for {target_ip_address}: "
                     f"Packets: Sent = {pings}, "
                     f"Received = {request_replies}, "
                     f"Lost = {pings - request_replies} ({(pings - request_replies) / pings * 100}% loss)"
                 )
+                self.sys_log.info(output)
+                print(output)
                 return passed
         return False
 
@@ -1456,12 +1497,18 @@ class Node(SimComponent):
                 self.icmp.process_icmp(frame=frame, from_nic=from_nic)
                 return
             # Check if the destination port is open on the Node
-            if frame.tcp.dst_port in self.software_manager.get_open_ports():
+            dst_port = None
+            if frame.tcp:
+                dst_port = frame.tcp.dst_port
+            elif frame.udp:
+                dst_port = frame.udp.dst_port
+            if dst_port in self.software_manager.get_open_ports():
                 # accept thr frame as the port is open
-                if frame.tcp.src_port == Port.ARP:
-                    self.arp.process_arp_packet(from_nic=from_nic, arp_packet=frame.arp)
-                else:
-                    self.session_manager.receive_frame(frame)
+                self.session_manager.receive_frame(frame, from_nic)
+                # if frame.tcp.src_port == Port.ARP:
+                #     self.arp.process_arp_packet(from_nic=from_nic, arp_packet=frame.arp)
+                # else:
+                #     self.session_manager.receive_frame(frame)
             else:
                 # denied as port closed
                 self.sys_log.info(f"Ignoring frame for port {frame.tcp.dst_port.value} from {frame.ip.src_ip_address}")

src/primaite/simulator/network/hardware/nodes/router.py

@@ -566,33 +566,32 @@ class RouterARPCache(ARPCache):
 
         # ARP Reply
         if not arp_packet.request:
-            for nic in self.router.nics.values():
-                if arp_packet.target_ip_address == nic.ip_address:
-                    # reply to the Router specifically
-                    self.sys_log.info(
-                        f"Received ARP response for {arp_packet.sender_ip_address} "
-                        f"from {arp_packet.sender_mac_addr} via NIC {from_nic}"
-                    )
-                    self.add_arp_cache_entry(
-                        ip_address=arp_packet.sender_ip_address,
-                        mac_address=arp_packet.sender_mac_addr,
-                        nic=from_nic,
-                    )
-                    return
-
-            # Reply for a connected requested
-            nic = self.get_arp_cache_nic(arp_packet.target_ip_address)
-            if nic:
+            if arp_packet.target_ip_address == from_nic.ip_address:
+                # reply to the Router specifically
                 self.sys_log.info(
-                    f"Forwarding arp reply for {arp_packet.target_ip_address}, from {arp_packet.sender_ip_address}"
+                    f"Received ARP response for {arp_packet.sender_ip_address} "
+                    f"from {arp_packet.sender_mac_addr} via NIC {from_nic}"
                 )
-                arp_packet.sender_mac_addr = nic.mac_address
-                frame.decrement_ttl()
-                if frame.ip and frame.ip.ttl < 1:
-                    self.sys_log.info("Frame discarded as TTL limit reached")
-                    return
-                nic.send_frame(frame)
-            return
+                self.add_arp_cache_entry(
+                    ip_address=arp_packet.sender_ip_address,
+                    mac_address=arp_packet.sender_mac_addr,
+                    nic=from_nic,
+                )
+                return
+
+            # # Reply for a connected requested
+            # nic = self.get_arp_cache_nic(arp_packet.target_ip_address)
+            # if nic:
+            #     self.sys_log.info(
+            #         f"Forwarding arp reply for {arp_packet.target_ip_address}, from {arp_packet.sender_ip_address}"
+            #     )
+            #     arp_packet.sender_mac_addr = nic.mac_address
+            #     frame.decrement_ttl()
+            #     if frame.ip and frame.ip.ttl < 1:
+            #         self.sys_log.info("Frame discarded as TTL limit reached")
+            #         return
+            #     nic.send_frame(frame)
+            # return
 
         # ARP Request
         self.sys_log.info(
@@ -606,28 +605,27 @@ class RouterARPCache(ARPCache):
 
         # If the target IP matches one of the router's NICs
         for nic in self.nics.values():
-            if arp_packet.target_ip_address in nic.ip_network:
-                # if nic.enabled and nic.ip_address == arp_packet.target_ip_address:
+            if nic.enabled and nic.ip_address == arp_packet.target_ip_address:
                 arp_reply = arp_packet.generate_reply(from_nic.mac_address)
                 self.send_arp_reply(arp_reply, from_nic)
                 return
 
-        # Check Route Table
-        route = route_table.find_best_route(arp_packet.target_ip_address)
-        if route:
-            nic = self.get_arp_cache_nic(route.next_hop_ip_address)
-
-            if not nic:
-                if not is_reattempt:
-                    self.send_arp_request(route.next_hop_ip_address, ignore_networks=[frame.ip.src_ip_address])
-                    return self.process_arp_packet(from_nic, frame, route_table, is_reattempt=True)
-                else:
-                    self.sys_log.info("Ignoring ARP request as destination unavailable/No ARP entry found")
-                    return
-            else:
-                arp_reply = arp_packet.generate_reply(from_nic.mac_address)
-                self.send_arp_reply(arp_reply, from_nic)
-            return
+        # # Check Route Table
+        # route = route_table.find_best_route(arp_packet.target_ip_address)
+        # if route and route != self.router.route_table.default_route:
+        #     nic = self.get_arp_cache_nic(route.next_hop_ip_address)
+        #
+        #     if not nic:
+        #         if not is_reattempt:
+        #             self.send_arp_request(route.next_hop_ip_address, ignore_networks=[frame.ip.src_ip_address])
+        #             return self.process_arp_packet(from_nic, frame, route_table, is_reattempt=True)
+        #         else:
+        #             self.sys_log.info("Ignoring ARP request as destination unavailable/No ARP entry found")
+        #             return
+        #     else:
+        #         arp_reply = arp_packet.generate_reply(from_nic.mac_address)
+        #         self.send_arp_reply(arp_reply, from_nic)
+        #     return
 
 
 class RouterICMP(ICMP):
@@ -949,13 +947,13 @@ class Router(Node):
             at_port = self._get_port_of_nic(from_nic)
             self.sys_log.info(f"Frame blocked at port {at_port} by rule {rule}")
             return
-        if not self.arp.get_arp_cache_nic(src_ip_address):
-            self.arp.add_arp_cache_entry(src_ip_address, frame.ethernet.src_mac_addr, from_nic)
+        self.arp.add_arp_cache_entry(src_ip_address, frame.ethernet.src_mac_addr, from_nic)
         if frame.ip.protocol == IPProtocol.ICMP:
             self.icmp.process_icmp(frame=frame, from_nic=from_nic)
         else:
             if src_port == Port.ARP:
                 self.arp.process_arp_packet(from_nic=from_nic, frame=frame, route_table=self.route_table)
+                return
             else:
                 # All other traffic
                 process_frame = True

src/primaite/simulator/network/transmission/data_link_layer.py

@@ -73,7 +73,7 @@ class Frame(BaseModel):
             msg = "Cannot build a Frame using the TCP IP Protocol without a TCPHeader"
             _LOGGER.error(msg)
             raise ValueError(msg)
-        if kwargs["ip"].protocol == IPProtocol.UDP and not kwargs.get("UDP"):
+        if kwargs["ip"].protocol == IPProtocol.UDP and not kwargs.get("udp"):
             msg = "Cannot build a Frame using the UDP IP Protocol without a UDPHeader"
             _LOGGER.error(msg)
             raise ValueError(msg)
@@ -95,8 +95,6 @@ class Frame(BaseModel):
     "UDP header."
     icmp: Optional[ICMPPacket] = None
     "ICMP header."
-    arp: Optional[ARPPacket] = None
-    "ARP packet."
     primaite: PrimaiteHeader
     "PrimAITE header."
     payload: Optional[Any] = None

src/primaite/simulator/system/core/session_manager.py

@@ -8,10 +8,10 @@ from prettytable import MARKDOWN, PrettyTable
 from primaite.simulator.core import SimComponent
 from primaite.simulator.network.transmission.data_link_layer import EthernetHeader, Frame
 from primaite.simulator.network.transmission.network_layer import IPPacket, IPProtocol
-from primaite.simulator.network.transmission.transport_layer import Port, TCPHeader
+from primaite.simulator.network.transmission.transport_layer import Port, TCPHeader, UDPHeader
 
 if TYPE_CHECKING:
-    from primaite.simulator.network.hardware.base import ARPCache
+    from primaite.simulator.network.hardware.base import ARPCache, NIC
     from primaite.simulator.system.core.software_manager import SoftwareManager
     from primaite.simulator.system.core.sys_log import SysLog
 
@@ -138,37 +138,19 @@ class SessionManager:
             dst_port = None
         return protocol, with_ip_address, src_port, dst_port
 
-    def receive_payload_from_software_manager(
-        self,
-        payload: Any,
-        dst_ip_address: Optional[Union[IPv4Address, IPv4Network]] = None,
-        dst_port: Optional[Port] = None,
-        session_id: Optional[str] = None,
-        is_reattempt: bool = False,
-    ) -> Union[Any, None]:
-        """
-        Receive a payload from the SoftwareManager and send it to the appropriate NIC for transmission.
-
-        This method supports both unicast and Layer 3 broadcast transmissions. If `dst_ip_address` is an
-        IPv4Network, a broadcast is initiated. For unicast, the destination MAC address is resolved via ARP.
-        A new session is established if `session_id` is not provided, and an existing session is used otherwise.
-
-        :param payload: The payload to be sent.
-        :param dst_ip_address: The destination IP address or network for broadcast. Optional.
-        :param dst_port: The destination port for the TCP packet. Optional.
-        :param session_id: The Session ID from which the payload originates. Optional.
-        :param is_reattempt: Flag to indicate if this is a reattempt after an ARP request. Default is False.
-        :return: The outcome of sending the frame, or None if sending was unsuccessful.
-        """
+    def resolve_outbound_transmission_details(
+        self, dst_ip_address: Optional[Union[IPv4Address, IPv4Network]] = None, session_id: Optional[str] = None
+    ) -> Tuple[Optional["NIC"], Optional[str], Optional[IPProtocol], bool]:
         is_broadcast = False
         outbound_nic = None
         dst_mac_address = None
+        protocol = None
 
         # Use session details if session_id is provided
         if session_id:
             session = self.sessions_by_uuid[session_id]
             dst_ip_address = session.with_ip_address
-            dst_port = session.dst_port
+            protocol = session.protocol
 
         # Determine if the payload is for broadcast or unicast
 
@@ -182,47 +164,81 @@ class SessionManager:
                     if dst_ip_address in nic.ip_network and nic.enabled:
                         dst_mac_address = "ff:ff:ff:ff:ff:ff"
                         outbound_nic = nic
+                        break
         else:
             # Resolve MAC address for unicast transmission
-            dst_mac_address = self.arp_cache.get_arp_cache_mac_address(dst_ip_address)
+            use_default_gateway = True
+            for nic in self.arp_cache.nics.values():
+                if dst_ip_address in nic.ip_network and nic.enabled:
+                    dst_mac_address = self.arp_cache.get_arp_cache_mac_address(dst_ip_address)
+                    break
 
-            # Resolve outbound NIC for unicast transmission
-            if dst_mac_address:
+            if dst_ip_address:
+                use_default_gateway = False
                 outbound_nic = self.arp_cache.get_arp_cache_nic(dst_ip_address)
 
-            # If MAC address not found, initiate ARP request
-            else:
-                if not is_reattempt:
-                    self.arp_cache.send_arp_request(dst_ip_address)
-                    # Reattempt payload transmission after ARP request
-                    return self.receive_payload_from_software_manager(
-                        payload=payload,
-                        dst_ip_address=dst_ip_address,
-                        dst_port=dst_port,
-                        session_id=session_id,
-                        is_reattempt=True,
-                    )
-                else:
-                    # Return None if reattempt fails
-                    return
+            if use_default_gateway:
+                dst_mac_address = self.arp_cache.get_default_gateway_mac_address()
+                outbound_nic = self.arp_cache.get_default_gateway_nic()
+        return outbound_nic, dst_mac_address, protocol, is_broadcast
+
+    def receive_payload_from_software_manager(
+        self,
+        payload: Any,
+        dst_ip_address: Optional[Union[IPv4Address, IPv4Network]] = None,
+        dst_port: Optional[Port] = None,
+        session_id: Optional[str] = None,
+        ip_protocol: IPProtocol = IPProtocol.TCP,
+    ) -> Union[Any, None]:
+        """
+        Receive a payload from the SoftwareManager and send it to the appropriate NIC for transmission.
+
+        This method supports both unicast and Layer 3 broadcast transmissions. If `dst_ip_address` is an
+        IPv4Network, a broadcast is initiated. For unicast, the destination MAC address is resolved via ARP.
+        A new session is established if `session_id` is not provided, and an existing session is used otherwise.
+
+        :param payload: The payload to be sent.
+        :param dst_ip_address: The destination IP address or network for broadcast. Optional.
+        :param dst_port: The destination port for the TCP packet. Optional.
+        :param session_id: The Session ID from which the payload originates. Optional.
+        :return: The outcome of sending the frame, or None if sending was unsuccessful.
+        """
+        print(ip_protocol)
+        outbound_nic, dst_mac_address, protocol, is_broadcast = self.resolve_outbound_transmission_details(
+            dst_ip_address=dst_ip_address, session_id=session_id
+        )
+
+        if protocol:
+            ip_protocol = protocol
+
+        print(ip_protocol)
 
         # Check if outbound NIC and destination MAC address are resolved
         if not outbound_nic or not dst_mac_address:
             return False
 
+        tcp_header = None
+        udp_header = None
+        if ip_protocol == IPProtocol.TCP:
+            TCPHeader(
+                src_port=dst_port,
+                dst_port=dst_port,
+            )
+        elif ip_protocol == IPProtocol:
+            udp_header = UDPHeader(
+                src_port=dst_port,
+                dst_port=dst_port,
+            )
+
         # Construct the frame for transmission
         frame = Frame(
             ethernet=EthernetHeader(src_mac_addr=outbound_nic.mac_address, dst_mac_addr=dst_mac_address),
-            ip=IPPacket(
-                src_ip_address=outbound_nic.ip_address,
-                dst_ip_address=dst_ip_address,
-            ),
-            tcp=TCPHeader(
-                src_port=dst_port,
-                dst_port=dst_port,
-            ),
+            ip=IPPacket(src_ip_address=outbound_nic.ip_address, dst_ip_address=dst_ip_address, ip_protocol=ip_protocol),
+            tcp=tcp_header,
+            udp_header=udp_header,
             payload=payload,
         )
+        print(frame)
 
         # Manage session for unicast transmission
         if not (is_broadcast and session_id):
@@ -237,7 +253,7 @@ class SessionManager:
         # Send the frame through the NIC
         return outbound_nic.send_frame(frame)
 
-    def receive_frame(self, frame: Frame):
+    def receive_frame(self, frame: Frame, from_nic: NIC):
         """
         Receive a Frame.
 
@@ -253,8 +269,13 @@ class SessionManager:
             session = Session.from_session_key(session_key)
             self.sessions_by_key[session_key] = session
             self.sessions_by_uuid[session.uuid] = session
+        dst_port = None
+        if frame.tcp:
+            dst_port = frame.tcp.dst_port
+        elif frame.udp:
+            dst_port = frame.udp.dst_port
         self.software_manager.receive_payload_from_session_manager(
-            payload=frame.payload, port=frame.tcp.dst_port, protocol=frame.ip.protocol, session_id=session.uuid
+            payload=frame.payload, port=dst_port, protocol=frame.ip.protocol, session_id=session.uuid, from_nic=from_nic
         )
 
     def show(self, markdown: bool = False):

src/primaite/simulator/system/core/software_manager.py

@@ -14,7 +14,7 @@ from primaite.simulator.system.software import IOSoftware
 if TYPE_CHECKING:
     from primaite.simulator.system.core.session_manager import SessionManager
     from primaite.simulator.system.core.sys_log import SysLog
-    from primaite.simulator.network.hardware.base import Node
+    from primaite.simulator.network.hardware.base import Node, NIC
 
 from typing import Type, TypeVar
 
@@ -52,11 +52,10 @@ class SoftwareManager:
 
         :return: A list of all open ports on the Node.
         """
-        open_ports = [Port.ARP]
+        open_ports = []
         for software in self.port_protocol_mapping.values():
             if software.operating_state in {ApplicationOperatingState.RUNNING, ServiceOperatingState.RUNNING}:
                 open_ports.append(software.port)
-        open_ports.sort(key=lambda port: port.value)
         return open_ports
 
     def install(self, software_class: Type[IOSoftwareClass]):
@@ -132,6 +131,7 @@ class SoftwareManager:
         payload: Any,
         dest_ip_address: Optional[Union[IPv4Address, IPv4Network]] = None,
         dest_port: Optional[Port] = None,
+        ip_protocol: IPProtocol = IPProtocol.TCP,
         session_id: Optional[str] = None,
     ) -> bool:
         """
@@ -154,7 +154,9 @@ class SoftwareManager:
             session_id=session_id,
         )
 
-    def receive_payload_from_session_manager(self, payload: Any, port: Port, protocol: IPProtocol, session_id: str):
+    def receive_payload_from_session_manager(
+        self, payload: Any, port: Port, protocol: IPProtocol, session_id: str, from_nic: "NIC"
+    ):
         """
         Receive a payload from the SessionManager and forward it to the corresponding service or application.
 
@@ -163,7 +165,7 @@ class SoftwareManager:
         """
         receiver: Optional[Union[Service, Application]] = self.port_protocol_mapping.get((port, protocol), None)
         if receiver:
-            receiver.receive(payload=payload, session_id=session_id)
+            receiver.receive(payload=payload, session_id=session_id, from_nic=from_nic)
         else:
             self.sys_log.error(f"No service or application found for port {port} and protocol {protocol}")
         pass

src/primaite/simulator/system/services/arp/arp.py

@@ -0,0 +1,201 @@
+from __future__ import annotations
+
+from abc import abstractmethod
+from ipaddress import IPv4Address
+from typing import Any, Dict, Optional, Tuple, Union
+
+from prettytable import MARKDOWN, PrettyTable
+from pydantic import BaseModel
+
+from primaite.simulator.network.hardware.base import NIC
+from primaite.simulator.network.protocols.arp import ARPEntry, ARPPacket
+from primaite.simulator.network.protocols.packet import DataPacket
+from primaite.simulator.network.transmission.data_link_layer import EthernetHeader, Frame
+from primaite.simulator.network.transmission.network_layer import IPPacket, IPProtocol
+from primaite.simulator.network.transmission.transport_layer import Port, TCPHeader, UDPHeader
+from primaite.simulator.system.services.service import Service
+
+
+class ARP(Service):
+    arp: Dict[IPv4Address, ARPEntry] = {}
+
+    def __init__(self, **kwargs):
+        kwargs["name"] = "ARP"
+        kwargs["port"] = Port.ARP
+        kwargs["protocol"] = IPProtocol.UDP
+        super().__init__(**kwargs)
+
+    def describe_state(self) -> Dict:
+        pass
+
+    def show(self, markdown: bool = False):
+        """Prints a table of ARC Cache."""
+        table = PrettyTable(["IP Address", "MAC Address", "Via"])
+        if markdown:
+            table.set_style(MARKDOWN)
+        table.align = "l"
+        table.title = f"{self.sys_log.hostname} ARP Cache"
+        for ip, arp in self.arp.items():
+            table.add_row(
+                [
+                    str(ip),
+                    arp.mac_address,
+                    self.software_manager.node.nics[arp.nic_uuid].mac_address,
+                ]
+            )
+        print(table)
+
+    def clear(self):
+        """Clears the arp cache."""
+        self.arp.clear()
+
+    def add_arp_cache_entry(self, ip_address: IPv4Address, mac_address: str, nic: NIC, override: bool = False):
+        """
+        Add an ARP entry to the cache.
+
+        If an entry for the given IP address already exists, the entry is only updated if the `override` parameter is
+        set to True.
+
+        :param ip_address: The IP address to be added to the cache.
+        :param mac_address: The MAC address associated with the IP address.
+        :param nic: The NIC through which the NIC with the IP address is reachable.
+        :param override: If True, an existing entry for the IP address will be overridden. Default is False.
+        """
+        for _nic in self.software_manager.node.nics.values():
+            if _nic.ip_address == ip_address:
+                return
+        if override or not self.arp.get(ip_address):
+            self.sys_log.info(f"Adding ARP cache entry for {mac_address}/{ip_address} via NIC {nic}")
+            arp_entry = ARPEntry(mac_address=mac_address, nic_uuid=nic.uuid)
+
+            self.arp[ip_address] = arp_entry
+
+    @abstractmethod
+    def get_arp_cache_mac_address(self, ip_address: IPv4Address) -> Optional[str]:
+        """
+        Get the MAC address associated with an IP address.
+
+        :param ip_address: The IP address to look up in the cache.
+        :return: The MAC address associated with the IP address, or None if not found.
+        """
+        pass
+
+    @abstractmethod
+    def get_arp_cache_nic(self, ip_address: IPv4Address) -> Optional[NIC]:
+        """
+        Get the NIC associated with an IP address.
+
+        :param ip_address: The IP address to look up in the cache.
+        :return: The NIC associated with the IP address, or None if not found.
+        """
+        pass
+
+    def send_arp_request(self, target_ip_address: Union[IPv4Address, str]):
+        """
+        Perform a standard ARP request for a given target IP address.
+
+        Broadcasts the request through all enabled NICs to determine the MAC address corresponding to the target IP
+        address. This method can be configured to ignore specific networks when sending out ARP requests,
+        which is useful in environments where certain addresses should not be queried.
+
+        :param target_ip_address: The target IP address to send an ARP request for.
+        :param ignore_networks: An optional list of IPv4 addresses representing networks to be excluded from the ARP
+            request broadcast. Each address in this list indicates a network which will not be queried during the ARP
+            request process. This is particularly useful in complex network environments where traffic should be
+            minimized or controlled to specific subnets. It is mainly used by the router to prevent ARP requests being
+            sent back to their source.
+        """
+        vals: Tuple = self.software_manager.session_manager.resolve_outbound_transmission_details(target_ip_address)
+        outbound_nic, _, _, _ = vals
+        if outbound_nic:
+            self.sys_log.info(f"Sending ARP request from NIC {outbound_nic} for ip {target_ip_address}")
+            arp_packet = ARPPacket(
+                sender_ip_address=outbound_nic.ip_address,
+                sender_mac_addr=outbound_nic.mac_address,
+                target_ip_address=target_ip_address,
+            )
+            self.software_manager.session_manager.receive_payload_from_software_manage(
+                payload=arp_packet, dst_port=Port.ARP, ip_protocol=self.protocol
+            )
+        else:
+            print(f"failed for {target_ip_address}")
+
+    def send_arp_reply(self, arp_reply: ARPPacket, from_nic: NIC):
+        """
+        Send an ARP reply back through the NIC it came from.
+
+        :param arp_reply: The ARP reply to send.
+        :param from_nic: The NIC to send the ARP reply from.
+        """
+        self.sys_log.info(
+            f"Sending ARP reply from {arp_reply.sender_mac_addr}/{arp_reply.sender_ip_address} "
+            f"to {arp_reply.target_ip_address}/{arp_reply.target_mac_addr} "
+        )
+        udp_header = UDPHeader(src_port=Port.ARP, dst_port=Port.ARP)
+
+        ip_packet = IPPacket(
+            src_ip_address=arp_reply.sender_ip_address,
+            dst_ip_address=arp_reply.target_ip_address,
+            protocol=IPProtocol.UDP,
+        )
+
+        ethernet_header = EthernetHeader(src_mac_addr=arp_reply.sender_mac_addr, dst_mac_addr=arp_reply.target_mac_addr)
+
+        frame = Frame(ethernet=ethernet_header, ip=ip_packet, udp=udp_header, payload=arp_reply)
+        from_nic.send_frame(frame)
+
+    def process_arp_packet(self, from_nic: NIC, arp_packet: ARPPacket):
+        """
+        Process a received ARP packet, handling both ARP requests and responses.
+
+        If an ARP request is received for the local IP, a response is sent back.
+        If an ARP response is received, the ARP cache is updated with the new entry.
+
+        :param from_nic: The NIC that received the ARP packet.
+        :param arp_packet: The ARP packet to be processed.
+        """
+
+        # Unmatched ARP Request
+        if arp_packet.target_ip_address != from_nic.ip_address:
+            self.sys_log.info(
+                f"Ignoring ARP request for {arp_packet.target_ip_address}. Current IP address is {from_nic.ip_address}"
+            )
+            return
+
+        # Matched ARP request
+        self.add_arp_cache_entry(
+            ip_address=arp_packet.sender_ip_address, mac_address=arp_packet.sender_mac_addr, nic=from_nic
+        )
+        arp_packet = arp_packet.generate_reply(from_nic.mac_address)
+        self.send_arp_reply(arp_packet, from_nic)
+
+    @abstractmethod
+    def _process_arp_request(self, arp_packet: ARPPacket, from_nic: NIC):
+        self.sys_log.info(
+            f"Received ARP request for {arp_packet.target_ip_address} from "
+            f"{arp_packet.sender_mac_addr}/{arp_packet.sender_ip_address} "
+        )
+
+    def _process_arp_reply(self, arp_packet: ARPPacket, from_nic: NIC):
+        self.sys_log.info(
+            f"Received ARP response for {arp_packet.sender_ip_address} "
+            f"from {arp_packet.sender_mac_addr} via NIC {from_nic}"
+        )
+        self.add_arp_cache_entry(
+            ip_address=arp_packet.sender_ip_address, mac_address=arp_packet.sender_mac_addr, nic=from_nic
+        )
+
+    def receive(self, payload: Any, session_id: str, **kwargs) -> bool:
+        if not isinstance(payload, ARPPacket):
+            print("failied on payload check", type(payload))
+            return False
+
+        from_nic = kwargs.get("from_nic")
+        if payload.request:
+            print(from_nic)
+            self._process_arp_request(arp_packet=payload, from_nic=from_nic)
+        else:
+            self._process_arp_reply(arp_packet=payload, from_nic=from_nic)
+
+    def __contains__(self, item: Any) -> bool:
+        return item in self.arp

src/primaite/simulator/system/services/arp/host_arp.py

@@ -0,0 +1,95 @@
+from __future__ import annotations
+
+from ipaddress import IPv4Address
+from typing import Optional
+
+from primaite.simulator.network.hardware.base import NIC
+from primaite.simulator.system.services.arp.arp import ARP, ARPPacket
+
+
+class HostARP(ARP):
+    def get_default_gateway_mac_address(self) -> Optional[str]:
+        if self.software_manager.node.default_gateway:
+            return self.get_arp_cache_mac_address(self.software_manager.node.default_gateway)
+
+    def get_default_gateway_nic(self) -> Optional[NIC]:
+        if self.software_manager.node.default_gateway:
+            return self.get_arp_cache_nic(self.software_manager.node.default_gateway)
+
+    def _get_arp_cache_mac_address(
+        self, ip_address: IPv4Address, is_reattempt: bool = False, is_default_gateway_attempt: bool = False
+    ) -> Optional[str]:
+        arp_entry = self.arp.get(ip_address)
+
+        if arp_entry:
+            return arp_entry.mac_address
+        else:
+            if not is_reattempt:
+                self.send_arp_request(ip_address)
+                return self._get_arp_cache_mac_address(
+                    ip_address=ip_address, is_reattempt=True, is_default_gateway_attempt=is_default_gateway_attempt
+                )
+            else:
+                if self.node.default_gateway:
+                    if not is_default_gateway_attempt:
+                        self.send_arp_request(self.node.default_gateway)
+                        return self._get_arp_cache_mac_address(
+                            ip_address=self.node.default_gateway, is_reattempt=True, is_default_gateway_attempt=True
+                        )
+        return None
+
+    def get_arp_cache_mac_address(self, ip_address: IPv4Address) -> Optional[str]:
+        """
+        Get the MAC address associated with an IP address.
+
+        :param ip_address: The IP address to look up in the cache.
+        :return: The MAC address associated with the IP address, or None if not found.
+        """
+        return self._get_arp_cache_mac_address(ip_address)
+
+    def _get_arp_cache_nic(
+        self, ip_address: IPv4Address, is_reattempt: bool = False, is_default_gateway_attempt: bool = False
+    ) -> Optional[NIC]:
+        arp_entry = self.arp.get(ip_address)
+
+        if arp_entry:
+            return self.nics[arp_entry.nic_uuid]
+        else:
+            if not is_reattempt:
+                self.send_arp_request(ip_address)
+                return self._get_arp_cache_nic(
+                    ip_address=ip_address, is_reattempt=True, is_default_gateway_attempt=is_default_gateway_attempt
+                )
+            else:
+                if self.node.default_gateway:
+                    if not is_default_gateway_attempt:
+                        self.send_arp_request(self.node.default_gateway)
+                        return self._get_arp_cache_nic(
+                            ip_address=self.node.default_gateway, is_reattempt=True, is_default_gateway_attempt=True
+                        )
+        return None
+
+    def get_arp_cache_nic(self, ip_address: IPv4Address) -> Optional[NIC]:
+        """
+        Get the NIC associated with an IP address.
+
+        :param ip_address: The IP address to look up in the cache.
+        :return: The NIC associated with the IP address, or None if not found.
+        """
+        return self._get_arp_cache_nic(ip_address)
+
+    def _process_arp_request(self, arp_packet: ARPPacket, from_nic: NIC):
+        super()._process_arp_request(arp_packet, from_nic)
+        # Unmatched ARP Request
+        if arp_packet.target_ip_address != from_nic.ip_address:
+            self.sys_log.info(
+                f"Ignoring ARP request for {arp_packet.target_ip_address}. Current IP address is {from_nic.ip_address}"
+            )
+            return
+
+        # Matched ARP request
+        self.add_arp_cache_entry(
+            ip_address=arp_packet.sender_ip_address, mac_address=arp_packet.sender_mac_addr, nic=from_nic
+        )
+        arp_packet = arp_packet.generate_reply(from_nic.mac_address)
+        self.send_arp_reply(arp_packet, from_nic)

src/primaite/simulator/system/software.py

@@ -8,6 +8,7 @@ from typing import Any, Dict, Optional, Union
 from primaite.simulator.core import _LOGGER, RequestManager, RequestType, SimComponent
 from primaite.simulator.file_system.file_system import FileSystem, Folder
 from primaite.simulator.network.hardware.node_operating_state import NodeOperatingState
+from primaite.simulator.network.transmission.network_layer import IPProtocol
 from primaite.simulator.network.transmission.transport_layer import Port
 from primaite.simulator.system.core.session_manager import Session
 from primaite.simulator.system.core.sys_log import SysLog
@@ -242,6 +243,8 @@ class IOSoftware(Software):
     "Indicates if the software uses UDP protocol for communication. Default is True."
     port: Port
     "The port to which the software is connected."
+    protocol: IPProtocol
+    "The IP Protocol the Software operates on."
     _connections: Dict[str, Dict] = {}
     "Active connections."