#2059: moved connection handling from Service to IOSoftware + changes that now utilise connections from IOSoftware + dos bot attacking now works + tests

src/primaite/simulator/system/applications/database_client.py

@@ -5,7 +5,7 @@ from uuid import uuid4
 from primaite import getLogger
 from primaite.simulator.network.transmission.network_layer import IPProtocol
 from primaite.simulator.network.transmission.transport_layer import Port
-from primaite.simulator.system.applications.application import Application, ApplicationOperatingState
+from primaite.simulator.system.applications.application import Application
 from primaite.simulator.system.core.software_manager import SoftwareManager
 
 _LOGGER = getLogger(__name__)
@@ -23,7 +23,6 @@ class DatabaseClient(Application):
 
     server_ip_address: Optional[IPv4Address] = None
     server_password: Optional[str] = None
-    connections: Dict[str, Dict] = {}
     _query_success_tracker: Dict[str, bool] = {}
 
     def __init__(self, **kwargs):
@@ -143,7 +142,7 @@ class DatabaseClient(Application):
             dest_ip_address=self.server_ip_address,
             dest_port=self.port,
         )
-        self.connections.pop(connection_id)
+        self.remove_connection(connection_id=connection_id)
 
         self.sys_log.info(
             f"{self.name}: DatabaseClient disconnected connection {connection_id} from {self.server_ip_address}"
@@ -181,8 +180,6 @@ class DatabaseClient(Application):
     def run(self) -> None:
         """Run the DatabaseClient."""
         super().run()
-        if self.operating_state == ApplicationOperatingState.RUNNING:
-            self.connect()
 
     def query(self, sql: str, connection_id: Optional[str] = None) -> bool:
         """
@@ -221,7 +218,8 @@ class DatabaseClient(Application):
         if isinstance(payload, dict) and payload.get("type"):
             if payload["type"] == "connect_response":
                 if payload["response"] is True:
-                    self.connections[payload.get("connection_id")] = payload
+                    # add connection
+                    self.add_connection(connection_id=payload.get("connection_id"), session_id=session_id)
             elif payload["type"] == "sql":
                 query_id = payload.get("uuid")
                 status_code = payload.get("status_code")

src/primaite/simulator/system/applications/red_applications/data_manipulation_bot.py

@@ -5,7 +5,6 @@ from typing import Optional
 from primaite import getLogger
 from primaite.game.science import simulate_trial
 from primaite.simulator.core import RequestManager, RequestType
-from primaite.simulator.system.applications.application import ApplicationOperatingState
 from primaite.simulator.system.applications.database_client import DatabaseClient
 
 _LOGGER = getLogger(__name__)
@@ -177,9 +176,9 @@ class DataManipulationBot(DatabaseClient):
 
         This is the core loop where the bot sequentially goes through the stages of the attack.
         """
-        if self.operating_state != ApplicationOperatingState.RUNNING:
+        if not self._can_perform_action():
             return
-        if self.server_ip_address and self.payload and self.operating_state:
+        if self.server_ip_address and self.payload:
             self.sys_log.info(f"{self.name}: Running")
             self._logon()
             self._perform_port_scan(p_of_success=self.port_scan_p_of_success)

src/primaite/simulator/system/applications/red_applications/dos_bot.py

@@ -0,0 +1,184 @@
+from enum import IntEnum
+from ipaddress import IPv4Address
+from typing import Optional
+
+from primaite import getLogger
+from primaite.game.science import simulate_trial
+from primaite.simulator.core import RequestManager, RequestType
+from primaite.simulator.network.transmission.transport_layer import Port
+from primaite.simulator.system.applications.application import Application
+from primaite.simulator.system.applications.database_client import DatabaseClient
+
+_LOGGER = getLogger(__name__)
+
+
+class DoSAttackStage(IntEnum):
+    """Enum representing the different stages of a Denial of Service attack."""
+
+    NOT_STARTED = 0
+    "Attack not yet started."
+
+    PORT_SCAN = 1
+    "Attack is in discovery stage - checking if provided ip and port are open."
+
+    ATTACKING = 2
+    "Denial of Service attack is in progress."
+
+    COMPLETED = 3
+    "Attack is completed."
+
+
+class DoSBot(DatabaseClient, Application):
+    """A bot that simulates a Denial of Service attack."""
+
+    target_ip_address: Optional[IPv4Address] = None
+    """IP address of the target service."""
+
+    target_port: Optional[Port] = None
+    """Port of the target service."""
+
+    payload: Optional[str] = None
+    """Payload to deliver to the target service as part of the denial of service attack."""
+
+    repeat: bool = False
+    """If true, the Denial of Service bot will keep performing the attack."""
+
+    attack_stage: DoSAttackStage = DoSAttackStage.NOT_STARTED
+    """Current stage of the DoS kill chain."""
+
+    port_scan_p_of_success: float = 0.1
+    """Probability of port scanning being sucessful."""
+
+    dos_intensity: float = 0.25
+    """How much of the max sessions will be used by the DoS when attacking."""
+
+    def __init__(self, **kwargs):
+        super().__init__(**kwargs)
+        self.name = "DoSBot"
+        self.max_sessions = 1000  # override normal max sessions
+
+    def set_original_state(self):
+        """Set the original state of the Denial of Service Bot."""
+        _LOGGER.debug(f"Setting {self.name} original state on node {self.software_manager.node.hostname}")
+        super().set_original_state()
+        vals_to_include = {
+            "target_ip_address",
+            "target_port",
+            "payload",
+            "repeat",
+            "attack_stage",
+            "max_sessions",
+            "port_scan_p_of_success",
+            "dos_intensity",
+        }
+        self._original_state.update(self.model_dump(include=vals_to_include))
+
+    def reset_component_for_episode(self, episode: int):
+        """Reset the original state of the SimComponent."""
+        _LOGGER.debug(f"Resetting {self.name} state on node {self.software_manager.node.hostname}")
+        super().reset_component_for_episode(episode)
+
+    def _init_request_manager(self) -> RequestManager:
+        rm = super()._init_request_manager()
+
+        rm.add_request(name="execute", request_type=RequestType(func=lambda request, context: self.run()))
+
+        return rm
+
+    def configure(
+        self,
+        target_ip_address: IPv4Address,
+        target_port: Optional[Port] = Port.POSTGRES_SERVER,
+        payload: Optional[str] = None,
+        repeat: bool = False,
+        max_sessions: int = 1000,
+    ):
+        """
+        Configure the Denial of Service bot.
+
+        :param: target_ip_address: The IP address of the Node containing the target service.
+        :param: target_port: The port of the target service. Optional - Default is `Port.HTTP`
+        :param: payload: The payload the DoS Bot will throw at the target service. Optional - Default is `None`
+        :param: repeat: If True, the bot will maintain the attack. Optional - Default is `True`
+        :param: max_sessions: The maximum number of sessions the DoS bot will attack with. Optional - Default is 1000
+        """
+        self.target_ip_address = target_ip_address
+        self.target_port = target_port
+        self.payload = payload
+        self.repeat = repeat
+        self.max_sessions = max_sessions
+        self.sys_log.info(
+            f"{self.name}: Configured the {self.name} with {target_ip_address=}, {target_port=}, {payload=}, {repeat=}."
+        )
+
+    def run(self):
+        """Run the Denial of Service Bot."""
+        super().run()
+        self._application_loop()
+
+    def _application_loop(self):
+        """
+        The main application loop for the Denial of Service bot.
+
+        The loop goes through the stages of a DoS attack.
+        """
+        if not self._can_perform_action():
+            return
+
+        # DoS bot cannot do anything without a target
+        if not self.target_ip_address or not self.target_port:
+            self.sys_log.error(
+                f"{self.name} is not properly configured. {self.target_ip_address=}, {self.target_port=}"
+            )
+            return
+
+        self.clear_connections()
+        self._perform_port_scan(p_of_success=self.port_scan_p_of_success)
+        self._perform_dos()
+
+        if self.repeat and self.attack_stage is DoSAttackStage.ATTACKING:
+            self.attack_stage = DoSAttackStage.NOT_STARTED
+        else:
+            self.attack_stage = DoSAttackStage.COMPLETED
+
+    def _perform_port_scan(self, p_of_success: Optional[float] = 0.1):
+        """
+        Perform a simulated port scan to check for open SQL ports.
+
+        Advances the attack stage to `PORT_SCAN` if successful.
+
+        :param p_of_success: Probability of successful port scan, by default 0.1.
+        """
+        if self.attack_stage == DoSAttackStage.NOT_STARTED:
+            # perform a port scan to identify that the SQL port is open on the server
+            if simulate_trial(p_of_success):
+                self.sys_log.info(f"{self.name}: Performing port scan")
+                # perform the port scan
+                port_is_open = True  # Temporary; later we can implement NMAP port scan.
+                if port_is_open:
+                    self.sys_log.info(f"{self.name}: ")
+                    self.attack_stage = DoSAttackStage.PORT_SCAN
+
+    def _perform_dos(self):
+        """
+        Perform the Denial of Service attack.
+
+        DoSBot does this by clogging up the available connections to a service.
+        """
+        if not self.attack_stage == DoSAttackStage.PORT_SCAN:
+            return
+        self.attack_stage = DoSAttackStage.ATTACKING
+        self.server_ip_address = self.target_ip_address
+        self.port = self.target_port
+
+        dos_sessions = int(float(self.max_sessions) * self.dos_intensity)
+        for i in range(dos_sessions):
+            self.connect()
+
+    def apply_timestep(self, timestep: int) -> None:
+        """
+        Apply a timestep to the bot, iterate through the application loop.
+
+        :param timestep: The timestep value to update the bot's state.
+        """
+        self._application_loop()

src/primaite/simulator/system/services/database/database_service.py

@@ -45,7 +45,7 @@ class DatabaseService(Service):
         super().set_original_state()
         vals_to_include = {
             "password",
-            "connections",
+            "_connections",
             "backup_server",
             "latest_backup_directory",
             "latest_backup_file_name",
@@ -55,7 +55,7 @@ class DatabaseService(Service):
     def reset_component_for_episode(self, episode: int):
         """Reset the original state of the SimComponent."""
         _LOGGER.debug("Resetting DatabaseService original state on node {self.software_manager.node.hostname}")
-        self.connections.clear()
+        self.clear_connections()
         super().reset_component_for_episode(episode)
 
     def configure_backup(self, backup_server: IPv4Address):
@@ -225,9 +225,6 @@ class DatabaseService(Service):
         :param session_id: The session identifier.
         :return: True if the Status Code is 200, otherwise False.
         """
-        if not super().receive(payload=payload, session_id=session_id, **kwargs):
-            return False
-
         result = {"status_code": 500, "data": []}
 
         # if server service is down, return error

src/primaite/simulator/system/services/ftp/ftp_client.py

@@ -20,9 +20,6 @@ class FTPClient(FTPServiceABC):
     RFC 959: https://datatracker.ietf.org/doc/html/rfc959
     """
 
-    connected: bool = False
-    """Keeps track of whether or not the FTP client is connected to an FTP server."""
-
     def __init__(self, **kwargs):
         kwargs["name"] = "FTPClient"
         kwargs["port"] = Port.FTP
@@ -129,10 +126,7 @@ class FTPClient(FTPServiceABC):
         software_manager.send_payload_to_session_manager(
             payload=payload, dest_ip_address=dest_ip_address, dest_port=dest_port
         )
-        if payload.status_code == FTPStatusCode.OK:
+        return payload.status_code == FTPStatusCode.OK
-            self.connected = False
-            return True
-        return False
 
     def send_file(
         self,
@@ -179,9 +173,9 @@ class FTPClient(FTPServiceABC):
             return False
 
         # check if FTP is currently connected to IP
-        self.connected = self._connect_to_server(dest_ip_address=dest_ip_address, dest_port=dest_port)
+        self._connect_to_server(dest_ip_address=dest_ip_address, dest_port=dest_port)
 
-        if not self.connected:
+        if not len(self.connections):
             return False
         else:
             self.sys_log.info(f"Sending file {src_folder_name}/{src_file_name} to {str(dest_ip_address)}")
@@ -230,9 +224,9 @@ class FTPClient(FTPServiceABC):
         :type: dest_port: Optional[Port]
         """
         # check if FTP is currently connected to IP
-        self.connected = self._connect_to_server(dest_ip_address=dest_ip_address, dest_port=dest_port)
+        self._connect_to_server(dest_ip_address=dest_ip_address, dest_port=dest_port)
 
-        if not self.connected:
+        if not len(self.connections):
             return False
         else:
             # send retrieve request
@@ -286,6 +280,14 @@ class FTPClient(FTPServiceABC):
             self.sys_log.error(f"FTP Server could not be found - Error Code: {FTPStatusCode.NOT_FOUND.value}")
             return False
 
+        # if PORT succeeded, add the connection as an active connection list
+        if payload.ftp_command is FTPCommand.PORT and payload.status_code is FTPStatusCode.OK:
+            self.add_connection(connection_id=session_id, session_id=session_id)
+
+        # if QUIT succeeded, remove the session from active connection list
+        if payload.ftp_command is FTPCommand.QUIT and payload.status_code is FTPStatusCode.OK:
+            self.remove_connection(connection_id=session_id)
+
         self.sys_log.info(f"{self.name}: Received FTP Response {payload.ftp_command.name} {payload.status_code.value}")
 
         self._process_ftp_command(payload=payload, session_id=session_id)

src/primaite/simulator/system/services/ftp/ftp_server.py

@@ -37,7 +37,7 @@ class FTPServer(FTPServiceABC):
     def reset_component_for_episode(self, episode: int):
         """Reset the original state of the SimComponent."""
         _LOGGER.debug(f"Resetting FTPServer state on node {self.software_manager.node.hostname}")
-        self.connections.clear()
+        self.clear_connections()
         super().reset_component_for_episode(episode)
 
     def _process_ftp_command(self, payload: FTPPacket, session_id: Optional[str] = None, **kwargs) -> FTPPacket:

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

@@ -1,5 +1,3 @@
-import copy
-from datetime import datetime
 from enum import Enum
 from typing import Any, Dict, Optional
 
@@ -42,9 +40,6 @@ class Service(IOSoftware):
     restart_countdown: Optional[int] = None
     "If currently restarting, how many timesteps remain until the restart is finished."
 
-    _connections: Dict[str, Dict] = {}
-    "Active connections to the Service."
-
     def __init__(self, **kwargs):
         super().__init__(**kwargs)
 
@@ -103,11 +98,6 @@ class Service(IOSoftware):
         rm.add_request("enable", RequestType(func=lambda request, context: self.enable()))
         return rm
 
-    @property
-    def connections(self) -> Dict[str, Dict]:
-        """Return the public version of connections."""
-        return copy.copy(self._connections)
-
     def describe_state(self) -> Dict:
         """
         Produce a dictionary describing the current state of this object.
@@ -123,56 +113,6 @@ class Service(IOSoftware):
         state["health_state_visible"] = self.health_state_visible.value
         return state
 
-    def add_connection(self, connection_id: str, session_id: Optional[str] = None) -> bool:
-        """
-        Create a new connection to this service.
-
-        Returns true if connection successfully created
-
-        :param: connection_id: UUID of the connection to create
-        :type: string
-        """
-        # if over or at capacity, set to overwhelmed
-        if len(self._connections) >= self.max_sessions:
-            self.health_state_actual = SoftwareHealthState.OVERWHELMED
-            self.sys_log.error(f"{self.name}: Connect request for {connection_id=} declined. Service is at capacity.")
-            return False
-        else:
-            # if service was previously overwhelmed, set to good because there is enough space for connections
-            if self.health_state_actual == SoftwareHealthState.OVERWHELMED:
-                self.health_state_actual = SoftwareHealthState.GOOD
-
-            # check that connection already doesn't exist
-            if not self._connections.get(connection_id):
-                session_details = None
-                if session_id:
-                    session_details = self._get_session_details(session_id)
-                self._connections[connection_id] = {
-                    "ip_address": session_details.with_ip_address if session_details else None,
-                    "time": datetime.now(),
-                }
-                self.sys_log.info(f"{self.name}: Connect request for {connection_id=} authorised")
-                return True
-            # connection with given id already exists
-            self.sys_log.error(
-                f"{self.name}: Connect request for {connection_id=} declined. Connection already exists."
-            )
-            return False
-
-    def remove_connection(self, connection_id: str) -> bool:
-        """
-        Remove a connection from this service.
-
-        Returns true if connection successfully removed
-
-        :param: connection_id: UUID of the connection to create
-        :type: string
-        """
-        if self._connections.get(connection_id):
-            self._connections.pop(connection_id)
-            self.sys_log.info(f"{self.name}: Connection {connection_id=} closed.")
-            return True
-
     def stop(self) -> None:
         """Stop the service."""
         if self.operating_state in [ServiceOperatingState.RUNNING, ServiceOperatingState.PAUSED]:

src/primaite/simulator/system/software.py

@@ -1,4 +1,6 @@
+import copy
 from abc import abstractmethod
+from datetime import datetime
 from enum import Enum
 from ipaddress import IPv4Address
 from typing import Any, Dict, Optional
@@ -206,6 +208,8 @@ 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."
+    _connections: Dict[str, Dict] = {}
+    "Active connections."
 
     def set_original_state(self):
         """Sets the original state."""
@@ -250,6 +254,65 @@ class IOSoftware(Software):
             return False
         return True
 
+    @property
+    def connections(self) -> Dict[str, Dict]:
+        """Return the public version of connections."""
+        return copy.copy(self._connections)
+
+    def add_connection(self, connection_id: str, session_id: Optional[str] = None) -> bool:
+        """
+        Create a new connection to this service.
+
+        Returns true if connection successfully created
+
+        :param: connection_id: UUID of the connection to create
+        :type: string
+        """
+        # if over or at capacity, set to overwhelmed
+        if len(self._connections) >= self.max_sessions:
+            self.health_state_actual = SoftwareHealthState.OVERWHELMED
+            self.sys_log.error(f"{self.name}: Connect request for {connection_id=} declined. Service is at capacity.")
+            return False
+        else:
+            # if service was previously overwhelmed, set to good because there is enough space for connections
+            if self.health_state_actual == SoftwareHealthState.OVERWHELMED:
+                self.health_state_actual = SoftwareHealthState.GOOD
+
+            # check that connection already doesn't exist
+            if not self._connections.get(connection_id):
+                session_details = None
+                if session_id:
+                    session_details = self._get_session_details(session_id)
+                self._connections[connection_id] = {
+                    "ip_address": session_details.with_ip_address if session_details else None,
+                    "time": datetime.now(),
+                }
+                self.sys_log.info(f"{self.name}: Connect request for {connection_id=} authorised")
+                return True
+            # connection with given id already exists
+            self.sys_log.error(
+                f"{self.name}: Connect request for {connection_id=} declined. Connection already exists."
+            )
+            return False
+
+    def remove_connection(self, connection_id: str) -> bool:
+        """
+        Remove a connection from this service.
+
+        Returns true if connection successfully removed
+
+        :param: connection_id: UUID of the connection to create
+        :type: string
+        """
+        if self.connections.get(connection_id):
+            self._connections.pop(connection_id)
+            self.sys_log.info(f"{self.name}: Connection {connection_id=} closed.")
+            return True
+
+    def clear_connections(self):
+        """Clears all the connections from the software."""
+        self._connections = {}
+
     def send(
         self,
         payload: Any,

tests/integration_tests/system/red_applications/test_dos_bot_and_server.py

@@ -0,0 +1,107 @@
+from ipaddress import IPv4Address
+from typing import Tuple
+
+import pytest
+
+from primaite.simulator.network.hardware.nodes.computer import Computer
+from primaite.simulator.network.hardware.nodes.server import Server
+from primaite.simulator.network.transmission.transport_layer import Port
+from primaite.simulator.system.applications.application import ApplicationOperatingState
+from primaite.simulator.system.applications.red_applications.dos_bot import DoSAttackStage, DoSBot
+from primaite.simulator.system.services.database.database_service import DatabaseService
+from primaite.simulator.system.software import SoftwareHealthState
+
+
+@pytest.fixture(scope="function")
+def dos_bot_and_db_server(client_server) -> Tuple[DoSBot, Computer, DatabaseService, Server]:
+    computer, server = client_server
+
+    # Install DoSBot on computer
+    computer.software_manager.install(DoSBot)
+
+    dos_bot: DoSBot = computer.software_manager.software.get("DoSBot")
+    dos_bot.configure(
+        target_ip_address=IPv4Address(server.nics.get(next(iter(server.nics))).ip_address),
+        target_port=Port.POSTGRES_SERVER,
+    )
+
+    # Install FTP Server service on server
+    server.software_manager.install(DatabaseService)
+    db_server_service: DatabaseService = server.software_manager.software.get("DatabaseService")
+    db_server_service.start()
+
+    return dos_bot, computer, db_server_service, server
+
+
+def test_repeating_dos_attack(dos_bot_and_db_server):
+    dos_bot, computer, db_server_service, server = dos_bot_and_db_server
+
+    assert db_server_service.health_state_actual is SoftwareHealthState.GOOD
+
+    dos_bot.port_scan_p_of_success = 1
+    dos_bot.repeat = True
+    dos_bot.run()
+
+    assert len(dos_bot.connections) == db_server_service.max_sessions
+    assert len(db_server_service.connections) == db_server_service.max_sessions
+    assert len(dos_bot.connections) == db_server_service.max_sessions
+
+    assert dos_bot.attack_stage is DoSAttackStage.NOT_STARTED
+    assert db_server_service.health_state_actual is SoftwareHealthState.OVERWHELMED
+
+    db_server_service.clear_connections()
+    db_server_service.health_state_actual = SoftwareHealthState.GOOD
+    assert len(db_server_service.connections) == 0
+
+    computer.apply_timestep(timestep=1)
+    server.apply_timestep(timestep=1)
+
+    assert len(dos_bot.connections) == db_server_service.max_sessions
+    assert len(db_server_service.connections) == db_server_service.max_sessions
+    assert len(dos_bot.connections) == db_server_service.max_sessions
+
+    assert dos_bot.attack_stage is DoSAttackStage.NOT_STARTED
+    assert db_server_service.health_state_actual is SoftwareHealthState.OVERWHELMED
+
+
+def test_non_repeating_dos_attack(dos_bot_and_db_server):
+    dos_bot, computer, db_server_service, server = dos_bot_and_db_server
+
+    assert db_server_service.health_state_actual is SoftwareHealthState.GOOD
+
+    dos_bot.port_scan_p_of_success = 1
+    dos_bot.repeat = False
+    dos_bot.run()
+
+    assert len(dos_bot.connections) == db_server_service.max_sessions
+    assert len(db_server_service.connections) == db_server_service.max_sessions
+    assert len(dos_bot.connections) == db_server_service.max_sessions
+
+    assert dos_bot.attack_stage is DoSAttackStage.COMPLETED
+    assert db_server_service.health_state_actual is SoftwareHealthState.OVERWHELMED
+
+    db_server_service.clear_connections()
+    db_server_service.health_state_actual = SoftwareHealthState.GOOD
+    assert len(db_server_service.connections) == 0
+
+    computer.apply_timestep(timestep=1)
+    server.apply_timestep(timestep=1)
+
+    assert len(dos_bot.connections) == 0
+    assert len(db_server_service.connections) == 0
+    assert len(dos_bot.connections) == 0
+
+    assert dos_bot.attack_stage is DoSAttackStage.COMPLETED
+    assert db_server_service.health_state_actual is SoftwareHealthState.GOOD
+
+
+def test_dos_bot_database_service_connection(dos_bot_and_db_server):
+    dos_bot, computer, db_server_service, server = dos_bot_and_db_server
+
+    dos_bot.operating_state = ApplicationOperatingState.RUNNING
+    dos_bot.attack_stage = DoSAttackStage.PORT_SCAN
+    dos_bot._perform_dos()
+
+    assert len(dos_bot.connections) == db_server_service.max_sessions
+    assert len(db_server_service.connections) == db_server_service.max_sessions
+    assert len(dos_bot.connections) == db_server_service.max_sessions

tests/unit_tests/_primaite/_simulator/_system/_applications/_red_applications/test_dos_bot.py

@@ -0,0 +1,90 @@
+from ipaddress import IPv4Address
+
+import pytest
+
+from primaite.simulator.network.hardware.node_operating_state import NodeOperatingState
+from primaite.simulator.network.hardware.nodes.computer import Computer
+from primaite.simulator.network.transmission.transport_layer import Port
+from primaite.simulator.system.applications.application import ApplicationOperatingState
+from primaite.simulator.system.applications.red_applications.dos_bot import DoSAttackStage, DoSBot
+
+
+@pytest.fixture(scope="function")
+def dos_bot() -> DoSBot:
+    computer = Computer(
+        hostname="compromised_pc",
+        ip_address="192.168.0.1",
+        subnet_mask="255.255.255.0",
+        operating_state=NodeOperatingState.ON,
+    )
+
+    computer.software_manager.install(DoSBot)
+
+    dos_bot: DoSBot = computer.software_manager.software.get("DoSBot")
+    dos_bot.configure(target_ip_address=IPv4Address("192.168.0.1"))
+    dos_bot.set_original_state()
+    return dos_bot
+
+
+def test_dos_bot_creation(dos_bot):
+    """Test that the DoS bot is installed on a node."""
+    assert dos_bot is not None
+
+
+def test_dos_bot_reset(dos_bot):
+    assert dos_bot.target_ip_address == IPv4Address("192.168.0.1")
+    assert dos_bot.target_port is Port.POSTGRES_SERVER
+    assert dos_bot.payload is None
+    assert dos_bot.repeat is False
+
+    dos_bot.configure(
+        target_ip_address=IPv4Address("192.168.1.1"), target_port=Port.HTTP, payload="payload", repeat=True
+    )
+
+    # should reset the relevant items
+    dos_bot.reset_component_for_episode(episode=0)
+    assert dos_bot.target_ip_address == IPv4Address("192.168.0.1")
+    assert dos_bot.target_port is Port.POSTGRES_SERVER
+    assert dos_bot.payload is None
+    assert dos_bot.repeat is False
+
+    dos_bot.configure(
+        target_ip_address=IPv4Address("192.168.1.1"), target_port=Port.HTTP, payload="payload", repeat=True
+    )
+    dos_bot.set_original_state()
+    dos_bot.reset_component_for_episode(episode=1)
+    # should reset to the configured value
+    assert dos_bot.target_ip_address == IPv4Address("192.168.1.1")
+    assert dos_bot.target_port is Port.HTTP
+    assert dos_bot.payload == "payload"
+    assert dos_bot.repeat is True
+
+
+def test_dos_bot_cannot_run_when_node_offline(dos_bot):
+    dos_bot_node: Computer = dos_bot.parent
+    assert dos_bot_node.operating_state is NodeOperatingState.ON
+
+    dos_bot_node.power_off()
+
+    for i in range(dos_bot_node.shut_down_duration + 1):
+        dos_bot_node.apply_timestep(timestep=i)
+
+    assert dos_bot_node.operating_state is NodeOperatingState.OFF
+
+    dos_bot._application_loop()
+
+    # assert not run
+    assert dos_bot.attack_stage is DoSAttackStage.NOT_STARTED
+
+
+def test_dos_bot_not_configured(dos_bot):
+    dos_bot.target_ip_address = None
+
+    dos_bot.operating_state = ApplicationOperatingState.RUNNING
+    dos_bot._application_loop()
+
+
+def test_dos_bot_perform_port_scan(dos_bot):
+    dos_bot._perform_port_scan(p_of_success=1)
+
+    assert dos_bot.attack_stage is DoSAttackStage.PORT_SCAN

tests/unit_tests/_primaite/_simulator/_system/_applications/test_database_client.py

@@ -63,10 +63,11 @@ def test_disconnect_when_client_is_closed(database_client_on_computer):
 
 
 def test_disconnect(database_client_on_computer):
-    """Database client should set connected to False and remove the database server ip address."""
+    """Database client should remove the connection."""
     database_client, computer = database_client_on_computer
 
-    database_client.connections[uuid4()] = {}
+    database_client._connections[str(uuid4())] = {"item": True}
+    assert len(database_client.connections) == 1
 
     assert database_client.operating_state is ApplicationOperatingState.RUNNING
     assert database_client.server_ip_address is not None
@@ -75,6 +76,14 @@ def test_disconnect(database_client_on_computer):
 
     assert len(database_client.connections) == 0
 
+    uuid = str(uuid4())
+    database_client._connections[uuid] = {"item": True}
+    assert len(database_client.connections) == 1
+
+    database_client.disconnect(connection_id=uuid)
+
+    assert len(database_client.connections) == 0
+
 
 def test_query_when_client_is_closed(database_client_on_computer):
     """Database client should return False when it is not running."""

tests/unit_tests/_primaite/_simulator/_system/_services/test_services.py

@@ -1,3 +1,5 @@
+from uuid import uuid4
+
 from primaite.simulator.system.services.service import ServiceOperatingState
 from primaite.simulator.system.software import SoftwareHealthState
 
@@ -66,3 +68,34 @@ def test_enable_disable(service):
 
     service.enable()
     assert service.operating_state == ServiceOperatingState.STOPPED
+
+
+def test_overwhelm_service(service):
+    service.max_sessions = 2
+    service.start()
+
+    uuid = str(uuid4())
+    assert service.add_connection(connection_id=uuid)  # should be true
+    assert service.health_state_actual is SoftwareHealthState.GOOD
+
+    assert not service.add_connection(connection_id=uuid)  # fails because connection already exists
+    assert service.health_state_actual is SoftwareHealthState.GOOD
+
+    assert service.add_connection(connection_id=str(uuid4()))  # succeed
+    assert service.health_state_actual is SoftwareHealthState.GOOD
+
+    assert not service.add_connection(connection_id=str(uuid4()))  # fail because at capacity
+    assert service.health_state_actual is SoftwareHealthState.OVERWHELMED
+
+
+def test_create_and_remove_connections(service):
+    service.start()
+    uuid = str(uuid4())
+
+    assert service.add_connection(connection_id=uuid)  # should be true
+    assert len(service.connections) == 1
+    assert service.health_state_actual is SoftwareHealthState.GOOD
+
+    assert service.remove_connection(connection_id=uuid)  # should be true
+    assert len(service.connections) == 0
+    assert service.health_state_actual is SoftwareHealthState.GOOD