ssh_server

import socket
import paramiko
import threading
import sys

# using the key from the Paramiko demo files
host_key = paramiko.RSAKey(filename='test_rsa.key')

class Server (paramiko.ServerInterface):

    def _init_(self):
        self.event = threading.Event()
# This function Checks if there is any session is created or not
    def check_channel_request(self, kind, chanid):
        if kind == 'session':
            return paramiko.OPEN_SUCCEEDED
        return paramiko.OPEN_FAILED_ADMINISTRATIVELY_PROHIBITED
    def check_auth_password(self, username, password):
        if (username == 'harman') and (password == '5007'):
            return paramiko.AUTH_SUCCESSFUL
        return paramiko.AUTH_FAILED

server = sys.argv[1]
ssh_port = int(sys.argv[2])

try:
    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

#  socket.SO_REUSEADDR allows protocols to use the same port on localhost              #_____multiple times only if protocols request it

    sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
    sock.bind((server, ssh_port))
    sock.listen(100)
    print('[+] Listening for connection ...')
    client, addr = sock.accept()
except Exception as e:
    print (f'[-] Listen failed: {e}')
    sys.exit(1)

print('[+] Got a connection!')

try:
    bhSession = paramiko.Transport(client)
    #ssh.load_system_host_keys()
    bhSession.add_server_key(host_key)
    server1 = Server()
    try:
        bhSession.start_server(server=server1)

    except paramiko.SSHException as x:
        print ('[-] SSH negotiation failed.')

    chan = bhSession.accept(20)
    print('[+] Authenticated!')
    #chan.send('Welcome to bh_ssh'.encode('utf-8'))
    print(chan.recv(4096).decode('utf-8'))
    chan.send('Welcome to bh_ssh'.encode('utf-8'))

    while not chan.closed:
        try:
            command = input("Enter command: ").rstrip()
            #if len(command):
            if command != 'exit':
                chan.send(command)
                print(chan.recv(4096).decode('utf-8') + '\n')
            else:
                print('exiting')
                bhSession.close()
                print("[*] SSH session closed")
                sys.exit(1)
        except Exception as err:
            print("[*] Caught Exception: ", str(err))
            print("[*] Exiting Script")

except Exception as e :
    print (f'[-] Caught exception:{e}')
    sys.exit(1)