added reverse lookup script

Author: krishnaprasanthg

README.md

@@ -67,9 +67,16 @@ Happy scripting!
 
 #### Requirements : 
     Python 3.5+
-    
+
+### RevereLookup : 
+    Takes an input list of ip addresses and does a reverse lookup for dns information and org information and writes to a csv file.
+
+#### Requirements : 
+    Python 3+, Requests
+
 ### WebsiteMonitor : 
     Monitor a website for a seach term. When it shows up, send yourself an e-mail. 
 
 #### Requirements : 
     Python 3.5+, Requests
+

ReverseLookup/ip_list.txt

@@ -0,0 +1,3 @@
+8.8.8.8
+1.1.1.1
+1.0.0.1

ReverseLookup/reverse_lookup.py

@@ -0,0 +1,64 @@
+"""
+This script retrieves information about IP addresses an generates a CSV file out of it
+ 
+Put a list of IPs in ip_list.txt in current directory (plain IPs, one per line)
+CSV output is written to out_file.csv in current directory
+
+Lookups are retrieved from extreme-ip-lookup.com website
+"""
+import csv
+import getpass
+import socket
+
+import requests
+from requests.packages.urllib3.exceptions import InsecureRequestWarning
+
+session = requests.session()
+session.verify = False
+
+requests.packages.urllib3.disable_warnings(InsecureRequestWarning)
+
+with open("out_file.csv", mode="w", newline='') as out_file, open('ip_list.txt') as ip_list:
+    out_file.write("SEP=,\n")
+
+    csvwriter = csv.writer(out_file)
+    csvwriter.writerow([
+        "IP",
+        "Name",
+        "Location",
+        "LookupName",
+        "ISP",
+        "Organization",
+    ])
+
+    for ip in ip_list.readlines():
+        ip = ip.strip()
+        try:
+            hostname, aliaslist, ipaddrlist = socket.gethostbyaddr(ip)
+        except:
+            hostname = ''
+
+        try:
+            response = session.get("https://extreme-ip-lookup.com/json/%s" % ip)
+            response.raise_for_status()
+            ip_data = response.json()
+
+            location = ip_data['country'] + ' ' + ip_data['continent']
+            ipName = ip_data['ipName']
+            isp = ip_data['isp']
+            org = ip_data['org']
+        except:
+            location = ''
+            ipName = ''
+            isp = ''
+            org = ''
+
+        print('%-20s%s' % (ip, hostname))
+        csvwriter.writerow([
+            ip,
+            hostname,
+            location,
+            ipName,
+            isp,
+            org,
+        ])