NetAlertX/server/networkscan.py

import conf

from database import insertOnlineHistory
from device import create_new_devices, print_scan_stats, save_scanned_devices, update_devices_data_from_scan
from helper import timeNowTZ
from logger import mylog
from reporting import skip_repeated_notifications



#===============================================================================
# SCAN NETWORK
#===============================================================================

def process_scan (db):

     # Load current scan data
    mylog('verbose','[Process Scan]  Processing scan results')     
    save_scanned_devices (db)    

    db.commitDB()
    
    # Print stats
    mylog('none','[Process Scan] Print Stats')
    print_scan_stats(db)
    mylog('none','[Process Scan] Stats end')

    # Create Events    
    mylog('verbose','[Process Scan] Sessions Events (connect / discconnect)')
    insert_events(db)

    # Create New Devices
    # after create events -> avoid 'connection' event
    mylog('verbose','[Process Scan] Creating new devices')
    create_new_devices (db)

    # Update devices info
    mylog('verbose','[Process Scan] Updating Devices Info')
    update_devices_data_from_scan (db)

    # Void false connection - disconnections
    mylog('verbose','[Process Scan] Voiding false (ghost) disconnections')    
    void_ghost_disconnections (db)

    # Pair session events (Connection / Disconnection)
    mylog('verbose','[Process Scan] Pairing session events (connection / disconnection) ')
    pair_sessions_events(db)  
  
    # Sessions snapshot
    mylog('verbose','[Process Scan] Creating sessions snapshot')
    create_sessions_snapshot (db)

    # Sessions snapshot
    mylog('verbose','[Process Scan] Inserting scan results into Online_History')
    insertOnlineHistory(db)
  
    # Skip repeated notifications
    mylog('verbose','[Process Scan] Skipping repeated notifications')
    skip_repeated_notifications (db)

    # Clear current scan as processed 
    db.sql.execute ("DELETE FROM CurrentScan") 
  
    # Commit changes    
    db.commitDB()

#-------------------------------------------------------------------------------
def void_ghost_disconnections (db):
    sql = db.sql #TO-DO
    startTime = timeNowTZ()
    # Void connect ghost events (disconnect event exists in last X min.) 
    mylog('debug','[Void Ghost Con] - 1 Connect ghost events')
    sql.execute("""UPDATE Events SET eve_PairEventRowid = Null,
                                eve_EventType ='VOIDED - ' || eve_EventType
                            WHERE eve_MAC != 'Internet'
                            AND eve_EventType = 'Connected'
                            AND eve_DateTime = ?
                            AND eve_MAC IN (
                                SELECT Events.eve_MAC
                                FROM CurrentScan, Devices, Events 
                                WHERE dev_MAC = cur_MAC
                                    AND eve_MAC = cur_MAC
                                    AND eve_EventType = 'Disconnected'
                                    AND eve_DateTime >= DATETIME(?, '-3 minutes')
                                ) """,
                            (startTime, startTime))

    # Void connect paired events
    mylog('debug','[Void Ghost Con] - 2 Paired events')
    sql.execute("""UPDATE Events SET eve_PairEventRowid = Null 
                            WHERE eve_MAC != 'Internet'
                            AND eve_PairEventRowid IN (
                                SELECT Events.RowID
                                FROM CurrentScan, Devices, Events 
                                WHERE dev_MAC = cur_MAC
                                    AND eve_MAC = cur_MAC
                                    AND eve_EventType = 'Disconnected'
                                    AND eve_DateTime >= DATETIME(?, '-3 minutes')
                                ) """,
                            (startTime,))

    # Void disconnect ghost events 
    mylog('debug','[Void Ghost Con] - 3 Disconnect ghost events')
    sql.execute("""UPDATE Events SET eve_PairEventRowid = Null, 
                            eve_EventType = 'VOIDED - '|| eve_EventType
                        WHERE eve_MAC != 'Internet'
                        AND ROWID IN (
                            SELECT Events.RowID
                            FROM CurrentScan, Devices, Events 
                            WHERE dev_MAC = cur_MAC
                                AND eve_MAC = cur_MAC
                                AND eve_EventType = 'Disconnected'
                                AND eve_DateTime >= DATETIME(?, '-3 minutes')
                            ) """,
                (startTime,))

    mylog('debug','[Void Ghost Con] Void Ghost Connections end')

    db.commitDB()

#-------------------------------------------------------------------------------
def pair_sessions_events (db):
    sql = db.sql #TO-DO
   

    # Pair Connection / New Device events
    mylog('debug','[Pair Session] - 1 Connections / New Devices')
    sql.execute ("""UPDATE Events
                    SET eve_PairEventRowid =
                       (SELECT ROWID
                        FROM Events AS EVE2
                        WHERE EVE2.eve_EventType IN ('New Device', 'Connected',
                            'Device Down', 'Disconnected')
                           AND EVE2.eve_MAC = Events.eve_MAC
                           AND EVE2.eve_Datetime > Events.eve_DateTime
                        ORDER BY EVE2.eve_DateTime ASC LIMIT 1)
                    WHERE eve_EventType IN ('New Device', 'Connected')
                    AND eve_PairEventRowid IS NULL
                 """ )

    # Pair Disconnection / Device Down
    mylog('debug','[Pair Session] - 2 Disconnections')
    sql.execute ("""UPDATE Events
                    SET eve_PairEventRowid =
                        (SELECT ROWID
                         FROM Events AS EVE2
                         WHERE EVE2.eve_PairEventRowid = Events.ROWID)
                    WHERE eve_EventType IN ('Device Down', 'Disconnected')
                      AND eve_PairEventRowid IS NULL
                 """ )
    mylog('debug','[Pair Session] Pair session end')

    db.commitDB()

#-------------------------------------------------------------------------------
def create_sessions_snapshot (db):
    sql = db.sql #TO-DO

    # Clean sessions snapshot
    mylog('debug','[Sessions Snapshot] - 1 Clean')
    sql.execute ("DELETE FROM SESSIONS" )

    # Insert sessions
    mylog('debug','[Sessions Snapshot] - 2 Insert')
    sql.execute ("""INSERT INTO Sessions
                    SELECT * FROM Convert_Events_to_Sessions""" )

    mylog('debug','[Sessions Snapshot] Sessions end')
    db.commitDB()


#-------------------------------------------------------------------------------
def insert_events (db):
    sql = db.sql #TO-DO
    startTime = timeNowTZ()    
    
    # Check device down
    mylog('debug','[Events] - 1 - Devices down')
    sql.execute (f"""INSERT INTO Events (eve_MAC, eve_IP, eve_DateTime,
                        eve_EventType, eve_AdditionalInfo,
                        eve_PendingAlertEmail)
                    SELECT dev_MAC, dev_LastIP, '{startTime}', 'Device Down', '', 1
                    FROM Devices 
                    WHERE dev_AlertDeviceDown != 0
                      AND dev_PresentLastScan = 1                      
                      AND NOT EXISTS (SELECT 1 FROM CurrentScan
                                      WHERE dev_MAC = cur_MAC
                                         ) """)

    # Check new connections
    mylog('debug','[Events] - 2 - New Connections')
    sql.execute (f"""INSERT INTO Events (eve_MAC, eve_IP, eve_DateTime,
                        eve_EventType, eve_AdditionalInfo,
                        eve_PendingAlertEmail)
                    SELECT cur_MAC, cur_IP, '{startTime}', 'Connected', '', dev_AlertEvents
                    FROM Devices, CurrentScan
                    WHERE dev_MAC = cur_MAC  
                      AND dev_PresentLastScan = 0 """)

    # Check disconnections
    mylog('debug','[Events] - 3 - Disconnections')
    sql.execute (f"""INSERT INTO Events (eve_MAC, eve_IP, eve_DateTime,
                        eve_EventType, eve_AdditionalInfo,
                        eve_PendingAlertEmail)
                    SELECT dev_MAC, dev_LastIP, '{startTime}', 'Disconnected', '',
                        dev_AlertEvents
                    FROM Devices
                    WHERE dev_AlertDeviceDown = 0
                      AND dev_PresentLastScan = 1
                      AND NOT EXISTS (SELECT 1 FROM CurrentScan
                                      WHERE dev_MAC = cur_MAC
                                         ) """)

    # Check IP Changed
    mylog('debug','[Events] - 4 - IP Changes')
    sql.execute (f"""INSERT INTO Events (eve_MAC, eve_IP, eve_DateTime,
                        eve_EventType, eve_AdditionalInfo,
                        eve_PendingAlertEmail)
                    SELECT cur_MAC, cur_IP, '{startTime}', 'IP Changed',
                        'Previous IP: '|| dev_LastIP, dev_AlertEvents
                    FROM Devices, CurrentScan
                    WHERE dev_MAC = cur_MAC                        
                      AND dev_LastIP <> cur_IP """ )
    mylog('debug','[Events] - Events end')