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Python script stuck at queue.join()

I am trying to implement a server for handling many clients (from thenewboston python reverse shell tutorials). I have the exact same code but when i run the script it gets stuck at queue.join(). How to make it work? I am unable to figure it out.
Here is the code
import socket
import sys
import threading
from queue import Queue
NUMBER_OF_THREADS = 2
JOB_NUMBER = [1, 2]
queue = Queue()
all_connections = []
all_addresses = []
# thread 1
# create socket (allows two computers to connect)
def socket_create():
try:
global host # ip address of the server
global port # port is to identify the kind of data
global s
host = ''
port = 9999
s = socket.socket()
except socket.error as msg:
print("Socket creation error: " + str(msg))
return
# 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.bind((host, port))
s.listen(5)
# 5 is the no. of conections that can be made before server starts rejecting other requests
except socket.error as msg:
print("Socket binding error: " + str(msg) + "\n" + "Retrying...")
socket_bind()
return
# 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 establish: " + address[0])
except:
print("Error accepting connections")
return
# thread 2
# custom command promt for sending commands remotely
def start_turtle():
while True:
cmd = input('turtle> ')
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")
return
# listing all the connections with indexing in the custom promt
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)
return
# select a target client
def get_target(cmd):
try:
target = cmd.replace('select ', '')
target = int(target)
conn = all_connections[target]
print("You are now connected to " + str(all_addresses[target][0]))
print(str(all_addresses[target][0]) + '> ', end="")
return conn
except:
print("Not a valid selection")
return None
return
# connect with remote target client
def send_target_commands(conn):
while True:
try:
cmd = input()
if len(str.encode(cmd)) > 0:
conn.send(str.encode(cmd))
client_response = str(conn.recv(20480), "utf-8")
print(client_response, end="")
if cmd == "quit":
break
except:
print("Connection was lost")
break
return
# create worker threads
def create_workers():
for _ in range(NUMBER_OF_THREADS):
t = threading.Thread(target=work)
t.daemon = True
t.start
return
# do the next job in the queue (one handles connections, other sends commands)
def work():
while True:
x = queue.get()
if x == 1:
socket_create()
socket_bind()
accept_connections()
if x == 2:
start_turtle()
queue.task_done()
return
# create jobs for later extracting them and assigning them to the threads
def create_jobs():
for x in JOB_NUMBER:
queue.put(x)
queue.join()
return
def main():
create_workers()
create_jobs()
if __name__ == '__main__':
main()

Since you are using infinite loops (while True) at start_turtle and (while 1) at accept_connections they are not returning.
Since they don't return the func work never calls queue.task_done(), so the queue stuck joining.
I'm afraid you need to do one of the following:
start both start_turtle and accept_connections in parallel processes or threads.
Be sure they should call the queue.task_done().
For instance, you may include the queue as parameter and call it before starting the infinite loops (second option).
def work():
while True:
x = queue.get()
if x == 1:
socket_create()
socket_bind()
accept_connections(queue) # call queue.task_done() there
if x == 2:
start_turtle(queue) # call queue.task_done() in start_turtle
return
def start_turtle(queue):
queue.task_done() # Join one item from the queue
while True:
cmd = input('turtle> ')
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")
return
On the other hand, in your create_workers you don't call the start method of the thread so your workers didn't really start.
Perhaps this is a typo.
def create_workers():
for _ in range(NUMBER_OF_THREADS):
t = threading.Thread(target=work)
t.daemon = True
# t.start # Not starting the Thread
t.start() # You need to call the start method
return

Python says global name not defined

This is the code for p2p based on sockets that I am working on.
Whenever I try to execute this I get global name not defined error.
import socket
import os.path
import sys
import urlparse
import threading
class Node:
def startlisten(sock):
sock.listen(6)
while True:
c,addr = sock.accept()
print "Client connected all set to go : "+str(addr)
thread1 = threading(target=retrfile,args=(c,))
thread1.start()
def __init__(self):
self.port=raw_input("Enter the port: ")
self.shareddir=raw_input("Enter the name of the folder you want to share: ")
self.sysname=raw_input("Enter your desired nick name: ")
self.known=set()
self.s=socket.socket()
host = socket.gethostname()
port = int(self.port)
print host,port
self.s.bind((host,port))
t=threading.Thread(target=startlisten,args =(self.s,))
t.start()
def retrfile(sock):
code,filename = sock.recv(1024)
if code == 0:
if os.pathisfile(os.path.join("D:\\Sankalp0203\\",filename)):
sock.send("OK",str(os.path.getsize(filename)))
userResponse = sock.recv(1024)
if userResponse == 'Y':
with open(filename,'rb') as f:
bytestoread = f.read(1024)
sock.send(1024)
while bytestoread != "":
bytestoread = f.read(1024)
sock.send(byestoread)
def _hello(self,other):
self.known.add(other)
def _broadcast(self,query,history):
for other in self.known.copy():
if other in history:
continue
try:
name = urlparse(other)[1]
parts=name.split(":")
port = int(parts[-1])
host = "http://"+parts[0]
self.s.connect((host,port))
self.s.send(0,query)
code , size = s.recv(1024)
if code == "OK":
inp = raw_input("File Exists and filesize : "+str(size)+" download? y/n: ")
if inp == Y:
self.s.send(Y)
write(self.s,size)
return code , size,
except:
self.known.remove(other)
return FAIL,EMPTY
def write(sock1,size):
f = open('new'+filename,'wb')
data = sock1.recv(1024)
totalrecv = len(data)
f.write(data)
while(totalrecv < size):
data = sock1.recv(1024)
f.write(data)
totalrecv+=len(data)
def Main():
n=Node()
num=3
while(num):
input = (int)(raw_input("Enter 1 for fetch and 2 to sit idle and 3 to introduce to new peer"))
if(input == 1):
filename = raw_input("Enter the name of the file")
n.query(filename)
if(input == 3):
frnd =raw_input("Enter the url of the friend socket")
n._hello(frnd)
if __name__=='__main__':
Main()
When I execute this i get the following error saying global name not defined pls help
Traceback (most recent call last):
File "D:/Sankalp0203/P2Per.py", line 101, in <module>
Main()
File "D:/Sankalp0203/P2Per.py", line 89, in Main
n=Node()
File "D:/Sankalp0203/P2Per.py", line 28, in __init__
t=threading.Thread(target=startlisten,args =(self.s,))
NameError: global name 'startlisten' is not defined

It's saying that startlisten is not defined because global name startlisten is not defined. There is no global function called startlisten. The method you created is under the Node class. You missed the self. The right way to do it would be:
t=threading.Thread(target=self.startlisten,args =(self.s,))

Python - PARAMIKO SSH close session

I need help terminating my SSH session after my sendShell object runs through list commandfactory[].
I have a Python script where I use paramiko to connect to a cisco lab router via ssh; execute all commands in commandfactory[]; and output the results to the standard out. Everything seems to work except, I can't seem to get the SSH session to close after all my commands are ran. The session simply stays open until I terminate my script.
import threading, paramiko, re, os
class ssh:
shell = None
client = None
transport = None
def __init__(self, address, username, password):
print("Connecting to server on ip", str(address) + ".")
self.client = paramiko.client.SSHClient()
self.client.set_missing_host_key_policy(paramiko.client.AutoAddPolicy())
self.client.connect(address, username=username, password=password, look_for_keys=False)
self.transport = paramiko.Transport((address, 22))
self.transport.connect(username=username, password=password)
thread = threading.Thread(target=self.process)
thread.daemon = True
thread.start()
def closeConnection(self):
if(self.client != None):
self.client.close()
self.transport.close()
def openShell(self):
self.shell = self.client.invoke_shell()
def sendShell(self):
self.commandfactory = []
print("\nWelcome to Command Factory. Enter Commands you want to execute.\nType \"done\" when you are finished:")
while not re.search(r"done.*", str(self.commandfactory)):
self.commandfactory.append(input(":"))
if self.commandfactory[-1] == "done":
del self.commandfactory[-1]
break
print ("Here are the commands you're going to execute:\n" + str(self.commandfactory))
if(self.shell):
self.shell.send("enable" + "\n")
self.shell.send("ilovebeer" + "\n")
self.shell.send("term len 0" + "\n")
for cmdcnt in range(0,len(self.commandfactory)):
self.shell.send(self.commandfactory[cmdcnt] + "\n")
self.shell.send("exit" + "\n")
self.shell.send("\n")
else:
print("Shell not opened.")
def process(self):
global connection
while True:
# Print data when available
if self.shell != None and self.shell.recv_ready():
alldata = self.shell.recv(1024)
while self.shell.recv_ready():
alldata += self.shell.recv(1024)
strdata = str(alldata, "utf8")
strdata.strip()
print(strdata, end = "")
sshUsername = "adrian"
sshPassword = "ilovebeer"
sshServer = "10.10.254.129"
connection = ssh(sshServer, sshUsername, sshPassword)
connection.openShell()
while True:
connection.sendShell()
I would like the SSH session terminate once all the commands in my commandfactory list has been ran (CODE BELOW).
def sendShell(self):
self.commandfactory = []
print("\nWelcome to Command Factory. Enter Commands you want to execute.\nType \"done\" when you are finished:")
while not re.search(r"done.*", str(self.commandfactory)):
self.commandfactory.append(input(":"))
if self.commandfactory[-1] == "done":
del self.commandfactory[-1]
break
print ("Here are the commands you're going to execute:\n" + str(self.commandfactory))
if(self.shell):
self.shell.send("enable" + "\n")
self.shell.send("ilovebeer" + "\n")
self.shell.send("term len 0" + "\n")
for cmdcnt in range(0,len(self.commandfactory)):
self.shell.send(self.commandfactory[cmdcnt] + "\n")
self.shell.send("exit" + "\n")
self.shell.send("\n")
My code was mainly taken from https://daanlenaerts.com/blog/2016/07/01/python-and-ssh-paramiko-shell/. Much thanks to Daan Lenaerts for a good blog. I did make my own changes to fit my needs.

End the sendShell function with self.transport.close(), see http://docs.paramiko.org/en/2.0/api/transport.html

Was able to solve by adding self.shell.transport.close() after my iterator.
def sendShell(self):
self.commandfactory = []
print("\nWelcome to Command Factory. Enter Commands you want to execute.\nType \"done\" when you are finished:")
while not re.search(r"done.*", str(self.commandfactory)):
self.commandfactory.append(input(":"))
if self.commandfactory[-1] == "done":
del self.commandfactory[-1]
break
print ("Here are the commands you're going to execute:\n" + str(self.commandfactory))
if(self.shell):
self.shell.send("enable" + "\n")
self.shell.send("ilovebeer" + "\n")
self.shell.send("term len 0" + "\n")
for cmdcnt in range(0,len(self.commandfactory)):
self.shell.send(self.commandfactory[cmdcnt] + "\n")
self.shell.send("exit" + "\n")
self.shell.transport.close()

python thread waits for input before it prints

I'm writing a socket communication program, I have a main thread, and another thread trying to sock.recv()
when it does recieve bytes, it works as it needs, it goes to the right function, which at the end prints, and then the thread listens again to bytes (as wanted).
the problem is that the program won't print until I press enter...
if it matters i'm getting input at the same time in the main thread but it shouldn't matter.
note - the bytes are sent like this:
int (4 bytes) - msg type (string to print is 2)
int (4 bytes) - length of text to print
string ( bytes) - actual text
full code:
import socket
import time
import struct
import threading
import sys
PORT = 54321
def try_to_connect(ip):
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM,
socket.IPPROTO_TCP)
sock.settimeout(1)
try:
sock.connect((ip, PORT))
return sock
except:
return False
def text_parse(text, msg_id):
byte_text = bytes(text, "utf-8")
return struct.pack("II%ds" % len(byte_text), msg_id, len(byte_text), byte_text)
def main(sock):
global file_name
print("connected succefuly. to run a command, write $<command> (no space)\nto request a file, enter file path.\nto exit this program enter exit.")
inputed_text = ''
while True:
inputed_text = input()
if inputed_text == '':
pass
elif inputed_text == "exit":
return
elif inputed_text[0] == "$":
sock.send(text_parse(inputed_text[1:], 0))
else:
file_name = inputed_text
sock.send(text_parse(inputed_text, 1))
def print_string(message, msg_len):
text = struct.unpack("%ds" % msg_len, message)[0].decode("utf-8")
sys.stdout.write(text)
sys.stdout.flush()
def copy_file(message):
global file_name
final_file = open(file_name, "wb")
final_file.write(message)
final_file.close()
def recieve_loop(sock):
while True:
try:
header = sock.recv(8)
if not header: break
msg_type = struct.unpack("I", header[:4])[0]
msg_len = struct.unpack("I", header[4:8])[0]
print(msg_type)
print(msg_len)
message = sock.recv(msg_len)
if msg_type == 2:
print_string(message, msg_len)
elif msg_type == 3:
copy_file(message)
except socket.timeout:
pass
if __name__ == "__main__":
print("welcome to remote desktop program.\nto connect to your computer, enter it's ip.\nto exit enter exit")
text_input = "b,kjhkf"
while True:
text_input = input()
if text_input == "exit":
exit()
else:
sock = try_to_connect(text_input)
if sock:
socket_recieve_thread = threading.Thread(target = recieve_loop, args = [sock])
socket_recieve_thread.start()
main(sock)
socket_recieve_thread.join()
else:
print("the computer is not online")

Python imports module but doesn't recognize it when i initiate it?

I honestly have no idea why this is happening, I assume due to it not being on stack-exchange it's a very n00by mistake on my part. so here's the error:
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
UnboundLocalError: local variable 'socket' referenced before assignment
tcpServer.py
import socket
def Main():
UID = 1001
sockets = []
users = [] ## create usernames list
sessionLimit = input("session Queue Limit: ")
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind(('192.168.1.74', 12127))
s.listen(sessionLimit) ## listen for 1 connection at a time
while True:
c, addr = s.accept()
sockets.append(c)
users.append(c.recv(1024).decode('utf-8'))
print("Connection from " + str(addr))
data = c.recv(1024).decode('utf-8') ## recieve 1024 bytes from client at a time, and then decode it into utf-8
if not data:
break
temp == data
temp.split(" ")
if temp[0] == "//": ## check to see if user has sent command
if temp[1] == "msg":
for i in range(len(users)):
if users[i] == temp[2]:
sockets[i].send((" ".join(temp[::2])).encode('utf-8'))
else: ## else, send data to all users. Could just use s.sendall(data.encode('utf-8'))
for socket in sockets:
socket.send(data.encode('utf-8')) ## send to sockets[socket]
##print("From connected user: " + data)
##data = data.upper()
##print("Sending: " + data)
##c.send(data.encode('utf-8'))
## command listening
commands = input("-> ")
commands.split(" ")
if commands[0] == "exit":
c.close() ## close connection
elif commands[0] == "/msg":
for i in range(len(users)):
if users[i] == commands[1]:
sockets[i].send((" ".join(commands[::1])).encode('utf-8'))
"""
elif commands[0] == "/rename": ## dont implement yet, due to users[] length changing
for i in range(len(users)):
if users[i] == commands[1]:
sockets[i].send("<server_" + UID + "> rename " + commands[2].encode('utf-8'))
"""
c.close()
if __name__ == "__main__":
Main()
Thanks for any help !
- Jacob

The issue is that you're using the variable name socket in the context of your Main() function when you do the following code block:
for socket in sockets:
socket.send(data.encode('utf-8')) ## send to sockets[socket]
That's causing an naming issue with the socket library. If you change that to:
for sock in sockets:
sock.send(data.encode('utf-8')) ## send to sockets[socket]
It will start to work. I also had to indent your code differently to ensure it was all in the Main() function you set up, and had to ensure the input() was parsed as an int. For reference, here's the full code block working for me:
import socket
def Main():
UID = 1001
sockets = []
users = [] ## create usernames list
sessionLimit = int(input("session Queue Limit: "))
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind(('192.168.1.74', 12127))
s.listen(sessionLimit) ## listen for 1 connection at a time
while True:
c, addr = s.accept()
sockets.append(c)
users.append(c.recv(1024).decode('utf-8'))
print("Connection from " + str(addr))
data = c.recv(1024).decode('utf-8') ## recieve 1024 bytes from client at a time, and then decode it into utf-8
if not data:
break
temp == data
temp.split(" ")
if temp[0] == "//": ## check to see if user has sent command
if temp[1] == "msg":
for i in range(len(users)):
if users[i] == temp[2]:
sockets[i].send((" ".join(temp[::2])).encode('utf-8'))
else: ## else, send data to all users. Could just use s.sendall(data.encode('utf-8'))
for sock in sockets:
sock.send(data.encode('utf-8')) ## send to sockets[socket]
##print("From connected user: " + data)
##data = data.upper()
##print("Sending: " + data)
##c.send(data.encode('utf-8'))
## command listening
commands = input("-> ")
commands.split(" ")
if commands[0] == "exit":
c.close() ## close connection
elif commands[0] == "/msg":
for i in range(len(users)):
if users[i] == commands[1]:
sockets[i].send((" ".join(commands[::1])).encode('utf-8'))
"""
elif commands[0] == "/rename": ## dont implement yet, due to users[] length changing
for i in range(len(users)):
if users[i] == commands[1]:
sockets[i].send("<server_" + UID + "> rename " + commands[2].encode('utf-8'))
"""
c.close()
if __name__ == "__main__":
Main()