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Python reverse listener using threading

I'm working on a project that requires me to make a Python reverse listener that can send commands to a client that connects to my server, below is my server code and i am stuck on how to get multiple connections from more than just one client at the same time.
thank you
#!/usr/bin/python3
import socket
import sys
import time
import threading
from queue import Queue
NUMBER_OF_THREADS = 2
JOB_NUMBER = [1, 2]
queue = Queue)
all_connections = []
all_addresses = []
# create socket
def socket_create():
try:
global host
global port
global s
host = '0.0.0.0'
port = 5555
s = socket.socket()
except socket.error as msg:
print("Socket creation error: " + str(msg))
# bind socket to port and wait for connection from client
def socket_bind():
try:
global host
global port
global s
print("Binding socket to port: " + str(port))
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
s.bind((host, port))
s.listen(5)
except socket.error as msg:
print("Socket binding error: " + str(msg))
time.sleep(5)
socket_bind()
# accept connections from multiple clients and save to list
def accept_connections():
for c in all_connections:
c.close()
del all_connections[:]
del all_addresses[:]
while 1:
try:
conn, address = s.accept()
conn.setblocking(1)
all_connections.append(conn)
all_addresses.append(address)
print("\nConnection has been established: " + address[0])
except:
print("Error accepting connections")
# interactive prompt
def start_luka():
while True:
cmd = input('luka> ')
if cmd == 'list':
list_connections()
elif 'select' in cmd:
conn = get_target(cmd)
if conn is not None:
send_target_commands(conn)
else:
print("Command not recognized")
# displays all current connections
def list_connections():
results = ''
for i, conn in enumerate(all_connections):
try:
conn.send(str.encode(' '))
conn.recv(20480)
except:
del all_connections[i]
del all_addresses[i]
continue
results += str(i) + ' ' + str(all_addresses[i][0]) + ' ' + str(all_addresses[i][1]) + '\n'
print('------ Clients -----' + '\n' + results)
def main():
socket_create()
socket_bind()
start_luka()
list_connections()
accept_connections()
main()
when i run this code it doesn't say the connection is established and it doesn't add the connection to the list i created.
and lastly i'm trying to make all of this automated, as in, the second a client connects to my server listener, these commands will automatically run (ls, pwd, IP a...ect) and a file would be created to store all the data so i can check it out later. not sure where to start on that.
thanks for helping

python UDP socket client need to send twice so that the server can receive the package

i have a client will send some string to my server. However, i need to send twice so that the server get the package. So for every package client wants to send the server, it needs to send twice. I do not understand why it went in this way.
my server's code that does listening:
sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
myIp = "0x2A"
myPort = 2222
targetPort = 0
myAddress = ("localhost",myPort)
bufferSize = 1024
def listen():
print('starting up on {} port {}'.format(*myAddress))
sock.bind(myAddress)
# sock.listen(1)
print("waiting for message")
# connection, client_address = sock.accept()
while True:
received = sock.recvfrom(bufferSize)[0]
address = sock.recvfrom(bufferSize)[1]
received = json.loads(received.decode())
source = received.get("source")
destination = received.get("destination")
length = received.get("length")
message = received.get("message")
protocol = received.get("protocol")
print("the source is: " + source)
if destination == myIp:
print("the message is: " + message)
print('sending back to sender...')
sock.sendto(message.encode(),address)
if protocol == 0:
print("protocol is: " + str(protocol))
elif protocol == 1:
print("protocol is: " + str(protocol))
print("write data to log file....")
f = open("log.txt","w")
f.write(message)
print('done!')
elif protocol == 2:
print("protocol is: " + str(protocol))
# sock.close()
print("exit")
sock.close()
sys.exit()
else:
print("this is not my package: \n" + "destination Ip is: " + destination + "\n my Ip is: " + myIp)
if not received:
break
my client's code that does the sending:
def send():
try:
sock.sendto(message.encode(),serverAddress)
print("message: " + message + " is sent")
finally:
print('closing socket')
sock.close()

received = sock.recvfrom(bufferSize)[0]
address = sock.recvfrom(bufferSize)[1]
The first recvfrom will do the first read. The second recvfrom will do another read. Voila: you need two reads. Instead you should do a single read:
received, address = socket.recvfrom(bufferSize)

Sending Client Data With a Timer

So I have a simple Client-Server.
They properly connect with command line arguments, send and receiving data.
When the server isn't up and running but the client executes: Attempt to connect, after 1 second display message that it timed out (3 times) before closing.
the closest i can come to it, is simply attempting it 3 times.
import sys
from socket import *
# Get the server hostname, port and data length as command line arguments
argv = sys.argv
host = argv[1]
port = argv[2]
count = argv[3]
# Command line argument is a string, change the port and count into integer
port = int(port)
count = int(count)
data = 'X' * count # Initialize data to be sent
# Create UDP client socket. Note the use of SOCK_DGRAM
clientsocket = socket(AF_INET, SOCK_DGRAM)
# Sending data to server
# times out after 1 second (?)
for i in range(3):
try:
print("Sending data to " + host + ", " + str(port) + ": " + data)
clientsocket.sendto(data.encode(),(host, port))
# Receive the server response
dataEcho, address = clientsocket.recvfrom(count)
# Display the server response as an output
print("Receive data from " + address[0] + ", " + str(address[1]) + ": " + dataEcho.decode())
break
except:
print("timed out")
finally:
#Close the client socket
clientsocket.close()
How would I add a timer to it? Just adding 1 second between each attempt instead of how I coded.

If you just want the program to sleep for x seconds you could import time, and then add time.sleep(num_of_seconds_to_sleep) after your clientsocket.close() line.

Python Socket Closes after One Connection/Command

The Client and Server can successfully connect however only one command can be issued. Been at this for a while and wanted some outside help, any feedback or suggested improvements would be great thanks in advance.
Been looking at other posts which suggest I may have prematurely closed the connection but I don't believe this to be true due to the fact the program doesn't throw any disconnection errors though I may be wrong.
client.py
import socket
import sys
import os
# Create a TCP/IP socket
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
##server = input("Enter server IP: ")
##print(server)
##
##port = int(input("Enter port: "))
##print(port)
def send_msg(msg):
sock.sendall(msg.encode())
def get_msg():
msg = sock.recv(2048).decode()
return msg
server = "127.0.0.1"
port = 100
sock.connect((server, port))
print("Connecting to " + server + " on port " + str(port) + "\n")
while True:
#Send data
msg = input(os.getcwd() + "> ")
print("Sending '" + msg + "'")
send_msg(msg)
#Response
#amnt_exp = len(msg)
#data = sock.recv(2048)
data = get_msg()
if data == "exit":
print("\nClosing connection")
sock.close()
else:
print("Received: \n" + data)
server.py
import socket
import sys
import os
import subprocess
#Create a TCP/IP Socket
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
##server = input("Enter server IP: ")
##print(server)
##
##port = int(input("Enter port: "))
##print(port)
def send_msg(msg):
conn.sendall(msg.encode())
def get_msg():
msg = conn.recv(2048).decode()
return msg
server = "127.0.0.1"
port = 100
#Config
sock.bind((server, port))
print("Bound to " + server + " on port " + str(port) + "\n")
sock.listen(1)
print("Waiting for a connection...")
while True:
conn, caddr = sock.accept()
print("Connected!\n")
print("Waiting for a command...")
#data = conn.recv(2048).decode()
data = get_msg()
#Exit
if data == "exit":
print("\nConnection closed")
conn.close()
print("Received '" + data + "'")
#Command Exec
call = subprocess.Popen(data, stdout = subprocess.PIPE, shell=True)
#Output
output, err = call.communicate()
call_status = call.wait()
#print("Output: ", output)
#print("Exit status: ", call_status)
#Reply
msg = "Command successful\n" + "Output: " + str(output) + "\n" + "Exit status:" + str(call_status)
print("Sending reply...")
print("\nWaiting for a command...")
send_msg(msg)

The problem is that your server loop only accepts a single command, and then it goes back to accept a whole new connection, and never looks at the old connection again.
Your output is pretty misleading, because it does print out Waiting for a command.... But that's only happening because you have an extra print("\nWaiting for a command...") before send_msg, and you don't have any output before sock.accept. You can see what's actually happening if you make your prints accurate. For example:
sock.listen(1)
while True:
print('Waiting for a connection...') # inside the loop, not before it
conn, caddr = sock.accept()
# ... etc. ...
print("Sending reply...")
# Don't print Waiting for a command here, because you aren't
send_msg(msg)
# And print something after the send succeeds
print("Sent")
print()
So, now you know what's wrong, how do you fix it?
Simple. We just need a nested loop. Once you accept a client connection, keep using that connection until they exit:
sock.listen(1)
while True:
print('Waiting for a connection...') # inside the loop, not before it
conn, caddr = sock.accept()
print("Connected!\n")
while True:
print("Waiting for a command...")
data = get_msg()
#Exit
if data == "exit":
print("\nConnection closed")
conn.close()
break # go back to the outer accept loop to get the next connection
print("Received '" + data + "'")
# ... etc. ...
print()

Why is my ID based TCP/IP server not working?

I'm building a tcp/ip server in python that works with clients.
Each client gets its own thread and its socket is added to a list called client_list.
there also is a variable "clients_connected" which stores the amount of connected clients.
for some reason it just works with one client at the moment.
Also when a client disconnects, it should be removed from client_list but I'm not sure how to do that.
Could you take a look at the code please? thanks a lot!
this thread is looking for incoming connections:
def addclientsthread(sock):
global client_list
conn, addr = sock.accept()
client_list += [conn]
print_line('Client connected on ' + addr[0] + "\n")
start_new_thread(clientthread, (conn,))
So when a client connects it gets its own "clientthread"
def clientthread(conn):
# handling connections.
global clients_connected
while True:
# Receiving from client
in_data = conn.recv(1024)
data = decrypt(in_data)
if data.lower().find("id=-1") != -1:
clients_connected += 1
print_line("new client ID set to " + str(clients_connected) + "\n")
crypted_msg = encrypt("SID=" + str(clients_connected))
conn.sendall(crypted_msg)
pass
elif data.lower().find("uin") == 0:
uin_id = int(data[4:])
clients_connected -= 1
break
else:
print_line(data)
if not data:
break
# If client disconnects
conn.close()
Oh and please don't hate, I just started coding :)
EDIT: This is the main code (not in a thread)
HOST = ''
PORT = 8820
clients_connected = 0
client_list = []
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
print('Socket created')
# Bind socket to host and port
try:
s.bind((HOST, PORT))
except socket.error, msg:
print 'Bind failed. Error Code : ' + str(msg[0]) + ' Message ' + msg[1]
sys.exit()
print 'Socket successfully binded'
# Start listening on socket
s.listen(100000)
print 'Socket is listening'
start_new_thread(addclientsthread, (s,))