packet sniffer - init commit

PacketSniffer.py

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+#Importing the necessary modules
+import logging
+from datetime import datetime
+import subprocess
+import sys
+
+#This will supress all messages that have less significance
+logging.getLogger("scapy.runtime").setLevel(logging.ERROR)
+logging.getLogger("scapy.interactive").setLevel(logging.ERROR)
+logging.getLogger("scapy.loading").setLevel(logging.ERROR)
+
+try:
+    from scapy.all import *
+
+except ImportError:
+    print("Scapy package for Python is not installed on your system.")
+    sys.exit()
+
+#Printing a message to the user; always use "sudo scapy" in Linux!
+print("\n! Make sure to run this program as ROOT !\n")
+
+#Asking the user for some parameters: interface on which sniff, the number of packets to sniff, the time interval to sniff, the protocol
+
+#Asking the user for input - the interface on which to run the sniffer
+net_iface = input("* Enter the interface on which to run the sniffer (e.g. 'enp0s8'): ")
+
+#Setting network interface in promiscuous mode
+'''
+Wikipedia: In computer  networking, promiscuous mode or "promisc mode"[1] is a mode for a wired network 
+interface controller (NIC) or wireless network interface controller (WNIC) that causes the controller to
+pass all traffic it receives to the central processing unit (CPU) rather than passing only the frames 
+that the controller is interned to receive.
+This mode is normally used for packet sniffing that takes place on a router or on a computer connected to a hub.
+'''
+try:
+    subprocess.call(["ifconfig", net_iface, "promisc"], stdout = None, stderr = None, shell = False)
+
+except:
+    print("\nFailed to configure interface as promiscuous.\n")
+
+else:
+    #Executed if the try clause does not raise an exception
+    print("\nInterface %s was set to PROMISC mode.\n" % net_iface)
+
+#APPLICATION #Part 2
+
+#Asking the user for the number of packets to sniff (the "count" parameter)
+pkt_to_sniff = input("* Enter the number of packets to capture (0 is infinity): ")
+
+#Consider the case when user enters 0 (infinity)
+if int(pkt_to_sniff) != 0:
+    print("\nThe program will capture %d packets.\n" % int(pkt_to_sniff))
+
+elif int(pkt_to_sniff) == 0:
+    print("\nThe program will capture packets until the timeout expires.\n")
+
+#Asking the user for the time interval to sniff (the "timeout" paramter)
+time_to_sniff = input("* Enter the number of seconds to run the capture: ")
+
+#Handling the value entered by the user
+if int(time_to_sniff) != 0:
+    print("\nThe program will capture packets for %d seconds.\n" % int(time_to_sniff))
+
+#Asking the user for any protocol filter he might want to apply to the sniffing process
+#For this example I chose three protocols: ARP, BOOTP, ICMP
+#You can customize this to add your own desired protocols
+proto_sniff = input("* Enter the protocol to filter by (arp|bootp|icmp|0 is all): ")
+
+#Considering the case when the user enters 0 (meaning all protocols)
+if (proto_sniff == "arp") or (proto_sniff == "bootp") or (proto_sniff == "icmp"):
+    print("\nThe program will capture only %s packets.\n" % proto_sniff.upper())
+
+elif (proto_sniff) == "0":
+    print("\nThe program will capture all protocols.\n")
+
+#Asking the user to enter the name and path of the log file to be created
+file_name = input("* Please give a name to the log file: ")
+
+#Creating the text file (if it doesn't exist) for packet logging and/or opening it for appending
+sniffer_log = open(file_name, "a")
+
+
+#APPLICATION #Part 3
+#This is the function that will be called for each captured packet
+#The function will extract parameters from the packet and then log each packet to the log file
+def packet_log(packet):
+
+    #Getting the current timestamp
+    now = datetime.now()
+
+    #Writing the packet information to the log file, also considering the protocol or 0 fo all protocols
+    if proto_sniff == "0":
+        #Writing the data to the log file
+        print("Time: " + str(now) + " Protocol: ALL" + " SMAC: " + packet[0].src + " DMAC: " + packet[0].dst, file = sniffer_log)
+
+    elif (proto_sniff == "arp") or (proto_sniff == "bootp") or (proto_sniff == "icmp"):
+        #Writing the data to the log file
+        print("Time: " + str(now) + " Protocol: " + proto_sniff.upper() + " SMAC: " + packet[0].src + " DMAC: " + packet[0].dst, file = sniffer_log)
+
+#Printing an informational message to the screen
+print("\n* Starting the capture...")
+
+#Running the sniffing process (with or without a filter)
+if proto_sniff == "0":
+    sniff(iface = net_iface, count = int(pkt_to_sniff), timeout = int(time_to_sniff), prn = packet_log)
+
+elif (proto_sniff == "arp") or (proto_sniff == "bootp") or (proto_sniff == "icmp"):
+    sniff(iface = net_iface, filter = proto_sniff, count = int(pkt_to_sniff), timeout = int(time_to_sniff), prn = packet_log)
+
+else:
+    print("\nCould not identify the protocol.\n")
+    sys.exit()
+
+#Printing the closing message
+print("\n* Please check the %s file to see the captured packets.\n" % file_name)
+
+#Closing the log file
+sniffer_log.close()
+
+#End of the program