added modular structure

Author: thewhitetulip

processarp.py

@@ -1,24 +1,31 @@
 #!/usr/bin/python
 
 #Author: Suraj Patil
-#Version: 1.0
+#Version: 2.0
 #Date: 27th March 2014
 
 #Reads a pcap file into python using scapy and produces a csv file as output in the following format: Timestamp, source MAC address, source IP address, Destination MAC address, Destination IP address
+#modular design, which makes it easy to include this source into another program, or to extend this one
 
 from scapy.all import *
 
-pcap_path = raw_input('Path of pcap file: ') # enter the path where you stored the pcap file
-file_path = raw_input('Enter target file name')  #enter the path where you want to create a csv file
+def main():
+   pcap_path = raw_input('Path of pcap file: ') # enter the path where you stored the pcap file
+   file_path = raw_input('Enter target file name')  #enter the path where you want to create a csv file
+   process(pcap_path, file_path)
 
-try:
-  file = open(file_path+'.csv','w')  #tries to opens the file in read mode
-  pkts = rdpcap(pcap_path)  #inbuilt function of scapy to read pcap files
-  for i in range(len(pkts)):
-    if ARP in pkts[i]:  #checks if the packet is an ARP packet or not
-     file.write('%d,%s,%s,%s,%s,%d,%s\n'%( pkts[i].time, pkts[i].hwsrc, pkts[i].psrc, pkts[i].hwdst, pkts[i].pdst, pkts[i].op))
-     print 'file write complete'
-     #Timestamp, source MAC address, source IP address, Destination MAC address, Destination IP address
-  file.close()
-except:
-  print 'some error occured'
+def process(pcap_path, file_path):
+   try:
+     file = open(file_path+'.csv','w')  #tries to opens the file in read mode
+     pkts = rdpcap(pcap_path)  #inbuilt function of scapy to read pcap files
+     for i in range(len(pkts)):
+       if ARP in pkts[i]:  #checks if the packet is an ARP packet or not
+        file.write('%d,%s,%s,%s,%s,%d,%s\n'%( pkts[i].time, pkts[i].hwsrc, pkts[i].psrc, pkts[i].hwdst, pkts[i].pdst, pkts[i].op))
+        print 'file write complete'
+        #Timestamp, source MAC address, source IP address, Destination MAC address, Destination IP address
+     file.close()
+   except:
+     print 'some error occured'
+
+
+main()