If you ever find yourself without access to Nmap here is some quick python code for testing the up/down status of 1000 TCP ports on a target host. The code is explained at the bottom:
#!/usr/bin/python
import socket
from termcolor import colored
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
socket.setdefaulttimeout(1)
host = input(“Enter the target host: “)
def portscanner(port):
if sock.connect_ex((host,port)):
print(colored(“Port %d is closed” % (port), ‘red’))
else:
print(colored(“port %d is open” % (port), ‘green’))
for port in range(1,1000):
portscanner(port)
Explanation:
import socket
from termcolor import colored
These 2 libraries are responsible for creating the connection to the target and for allowing us to add colour to the output
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
socket.setdefaulttimeout(1)
Sets the connection to use IP4 and sets the timeout to 1 second so you don’t get stuck waiting for connection requests to time out
host = input(“Enter the target host: “)
This is the prompt which you see when you run the code, it adds the input to the ‘host’ variable
def portscanner(port):
if sock.connect_ex((host,port)):
print(colored(“Port %d is closed” % (port), ‘red’))
else:
print(colored(“port %d is open” % (port), ‘green’))
Here is the main function. Instead of testing for a successful connection it looks for a failure, if so it reports that the port is closed. If anything else comes back it assumes the port is open and reports that.
for port in range(1,1000):
Sets the script to scan ports 1- 1000, you can change this to specific numbers or increase the range up to 65535
Urban Security Research 