Hello I've been trying to make my python sock server connection counter to go down
but I can't figure out how I can do this
def client_thread(conn):
while True:
conn.send("Command: ")
data = conn.recv(1024)
if not data:
break
reply = "" + data
conn.sendall("\r")
if data == "!* Connections":
conn.sendall("[+] Clients Connected: %s \r\n" % (clients))
conn.close()
while True:
conn, addr = sock.accept()
clients = clients + 1
start_new_thread(client_thread, (conn,))
sock.close()
I needn't show you all of the code because its irrelevant to this issue,
I have provided the code that make's the counter go up when a new connection connects, but as said before I don't know how to make it go down when a connection leaves.
When trying to find solutions online there show's nothing that can help my issue
Here is a small sample how to realize a client counter with the select.select function. I actually took it from the great article select – Wait for I/O Efficiently on pymotw.com and added a client counter. Basically you look for readable sockets and try to receive data from them. If a socket returns nothing it means it has been closed and can be removed from the client list.
import queue
import socket
import select
clients = 0
sock = socket.socket()
sock.bind(('localhost', 5000))
sock.listen(5)
inputs = [sock]
outputs = []
msg_queues = {}
while inputs:
readable, writable, exceptional = select.select(
inputs, outputs, msg_queues)
for s in readable:
if s is sock:
conn, addr = sock.accept()
print('new connection from ', addr)
conn.setblocking(0)
inputs.append(conn)
msg_queues[conn] = queue.Queue()
# increment client counter
clients += 1
print('Clients: ', clients)
else:
# try to receive some data
data = s.recv(1024)
if data:
# if data available print it
print('Received {} from {}'.format(data, s.getpeername()))
msg_queues[s].put(data)
# add output channel for response
if s not in outputs:
outputs.append(s)
else:
# empty data will be interpreted as closed connection
print('Closing connection to ', s.getpeername())
# stop listening for input on the connection
if s in outputs:
outputs.remove(s)
# remove from inputs
inputs.remove(s)
s.close()
# decrement client counter
clients -= 1
del msg_queues[s]
print('Clients: ', clients)
I have msg list and socket list and i want to change it between the 2 threads so one can change it and both can use the new one.
The code is the server of chat who more than 2 clients can connect and talk to each other
Here is the code:
import threading
import socket
import time
global Clients
global MsgQue
def inputmsg():
while 1:
try:
Clients.append(server.accept())
except socket.error:
print("No new Socket")
for cli in Clients:
try:
MsgQue.append(cli[0].recv(4096))
except socket.error:
print("Warning no input")
def outputmsg():
for cli in Clients:
if(MsgQue):
cli[0].send(MsgQue[0])
MsgQue.pop(0)
threads = []
server = socket.socket()
host = "127.0.0.1"
port = 1212
server.bind((host,port))
server.setblocking(0)
server.listen(5)
Clients = []
MsgQue = []
threading._start_new_thread(inputmsg,())
threading._start_new_thread(outputmsg,())
while 1:
if( 1 == 4):
print ("WTF")
i am working on a basic python program to get used to threading and networking and i have become a little unstuck at one section of my code.
what i have is:
#make a socket and loop to obtain connections
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
ads = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind(("127.0.0.1" , 4000))
ads.bind(("127.0.0.1" , 4001))
s.listen(10)
ads.listen(1)
socks = [s,ads]
connections = [] # list of connections
while True:
if ads:
(c,a) = ads.accept()
t = threading.Thread(target = admin_client, args = ())
t.start()
elif :
(c,a) = s.accept()
connections.append(c)
t = threading.Thread(target = handle_client, args = (c,a))
t.start()
What i was hoping to happen was when the ads port was accessed it would assign it to the admin_client method which it seems to perform but it will just do nothing if anything connects on the s port.
Does anyone have a solution for this so both clients will connect with no issues?
if ads: is always True. You need to use select. Since if ads: is always True you drop into (c,a) = ads.accept() which waits for someone to connect to the ads port.
Something like (untested):
r,w,x = select.select(socks,[],[])
if ads in r:
...
elif s in r:
...
So I'm making a port scanner in python...
import socket
ip = "External IP"
s = socket.socket(2, 1) #socket.AF_INET, socket.SOCK_STREAM
def porttry(ip, port):
try:
s.connect((ip, port))
return True
except:
return None
for port in range(0, 10000):
value = porttry(ip, port)
if value == None:
print("Port not opened on %d" % port)
else:
print("Port opened on %d" % port)
break
raw_input()
But this is too slow, I want to somehow be able to some how close or break code after a period of time of not returning anything.
In addition to setting socket timeout, you can also apply multi-threading technique to turbo boost the process. It will be, at best, N times faster when you have N ports to scan.
# This script runs on Python 3
import socket, threading
def TCP_connect(ip, port_number, delay, output):
TCPsock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
TCPsock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
TCPsock.settimeout(delay)
try:
TCPsock.connect((ip, port_number))
output[port_number] = 'Listening'
except:
output[port_number] = ''
def scan_ports(host_ip, delay):
threads = [] # To run TCP_connect concurrently
output = {} # For printing purposes
# Spawning threads to scan ports
for i in range(10000):
t = threading.Thread(target=TCP_connect, args=(host_ip, i, delay, output))
threads.append(t)
# Starting threads
for i in range(10000):
threads[i].start()
# Locking the main thread until all threads complete
for i in range(10000):
threads[i].join()
# Printing listening ports from small to large
for i in range(10000):
if output[i] == 'Listening':
print(str(i) + ': ' + output[i])
def main():
host_ip = input("Enter host IP: ")
delay = int(input("How many seconds the socket is going to wait until timeout: "))
scan_ports(host_ip, delay)
if __name__ == "__main__":
main()
here is a quick and simple port scanner, it scans 100000 ports in 180 sec:
import threading
import socket
target = 'pythonprogramming.net'
#ip = socket.gethostbyname(target)
def portscan(port):
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.settimeout(0.5)#
try:
con = s.connect((target,port))
print('Port :',port,"is open.")
con.close()
except:
pass
r = 1
for x in range(1,100):
t = threading.Thread(target=portscan,kwargs={'port':r})
r += 1
t.start()
Consider setting a timeout instead of a for loop by using socket.setdefaulttimeout(timeout).
This should be a bit faster.
#-*-coding:utf8;-*-
#qpy:3
#qpy:console
import socket
import os
# This is used to set a default timeout on socket
# objects.
DEFAULT_TIMEOUT = 0.5
# This is used for checking if a call to socket.connect_ex
# was successful.
SUCCESS = 0
def check_port(*host_port, timeout=DEFAULT_TIMEOUT):
''' Try to connect to a specified host on a specified port.
If the connection takes longer then the TIMEOUT we set we assume
the host is down. If the connection is a success we can safely assume
the host is up and listing on port x. If the connection fails for any
other reason we assume the host is down and the port is closed.'''
# Create and configure the socket.
sock = socket.socket()
sock.settimeout(timeout)
# the SO_REUSEADDR flag tells the kernel to reuse a local
# socket in TIME_WAIT state, without waiting for its natural
# timeout to expire.
sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
# Like connect(address), but return an error indicator instead
# of raising an exception for errors returned by the C-level connect()
# call (other problems, such as “host not found,” can still raise exceptions).
# The error indicator is 0 if the operation succeeded, otherwise the value of
# the errnovariable. This is useful to support, for example, asynchronous connects.
connected = sock.connect_ex(host_port) is SUCCESS
# Mark the socket closed.
# The underlying system resource (e.g. a file descriptor)
# is also closed when all file objects from makefile() are closed.
# Once that happens, all future operations on the socket object will fail.
# The remote end will receive no more data (after queued data is flushed).
sock.close()
# return True if port is open or False if port is closed.
return connected
con = check_port('www.google.com', 83)
print(con)
One can use threading.Thread and threading.Condition to synchronize port check and spawning new threads.
Script example usage:
python port_scan.py google.com 70 90
Checking 70 - 80
Checking 80 - 84
Checking 84 - 90
Found active port 80
Checking 90 - 91
Checking 91 - 94
All threads started ...
port_scan.py:
# import pdb
import socket, threading
from traceback import print_exc
class AllThreadsStarted(Exception): pass
class IPv4PortScanner(object):
def __init__(self, domain, timeout=2.0, port_range=(1024, 65535), threadcount=10):
self.domain = domain
self.timeout = timeout
self.port_range = port_range
self.threadcount = threadcount
self._lock = threading.Lock()
self._condition = threading.Condition(self._lock)
self._ports_active = []
self._ports_being_checked = []
self._next_port = self.port_range[0]
def check_port_(self, port):
"If connects then port is active"
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
sock.settimeout(self.timeout)
try:
sock.connect((self.domain, port))
with self._lock:
self._ports_active.append(port)
print ("Found active port {}".format(port))
sock.close()
except socket.timeout, ex:
return
except:
print_exc()
# pdb.set_trace()
def check_port(self, port):
"updates self._ports_being_checked list on exit of this method"
try:
self.check_port_(port)
finally:
self._condition.acquire()
self._ports_being_checked.remove(port)
self._condition.notifyAll()
self._condition.release()
def start_another_thread(self):
if self._next_port > self.port_range[1]:
raise AllThreadsStarted()
port = self._next_port
self._next_port += 1
t = threading.Thread(target=self.check_port, args=(port,))
# update books
with self._lock:
self._ports_being_checked.append(port)
t.start()
def run(self):
try:
while True:
self._condition.acquire()
while len(self._ports_being_checked) >= self.threadcount:
# we wait for some threads to complete the task
self._condition.wait()
slots_available = self.threadcount - len(self._ports_being_checked)
self._condition.release()
print ("Checking {} - {}".format(self._next_port, self._next_port+slots_available))
for i in xrange(slots_available):
self.start_another_thread()
except AllThreadsStarted, ex:
print ("All threads started ...")
except:
print_exc()
if __name__ == "__main__":
import sys
domain = sys.argv[1]
port_s = int(sys.argv[2])
port_e = int(sys.argv[3])
scanner = IPv4PortScanner(domain=domain, port_range=(port_s, port_e))
scanner.run()
I think that this one snippet could help you : http://www.coderholic.com/python-port-scanner/
socket.setdefaulttimeout(0.5)
This will make the program faster!
socket.setdefualttimeout (time)
is used to keep trying to connect with port for perticular time...when you send request and there is timeout set for 2 seconds so it will try to connect with port for 2 seconds....if there will be no response from that port in 2 seconds....it will be count as a dead port
The following port scanner has a few constants defined at the top that you can modify as needed:
PURPOSE -- help message for the command line
PORTS -- range of ports you would like scanned
POOL_SIZE -- number of processes to scan with
TIMEOUT -- how long to wait for server connection
Feel free to adapt this according to your requirements. Maybe add some command line arguments?
#! /usr/bin/env python3
import argparse
import collections
import itertools
import multiprocessing
import operator
import socket
PURPOSE = 'Scan for open ports on a computer.'
PORTS = range(1 << 16)
POOL_SIZE = 1 << 8
TIMEOUT = 0.01
def main():
"""Get computer to scan, connect with process pool, and show open ports."""
parser = argparse.ArgumentParser(description=PURPOSE)
parser.add_argument('host', type=str, help='computer you want to scan')
host = parser.parse_args().host
with multiprocessing.Pool(POOL_SIZE, socket.setdefaulttimeout, [TIMEOUT]) \
as pool:
results = pool.imap_unordered(test, ((host, port) for port in PORTS))
servers = filter(operator.itemgetter(0), results)
numbers = map(operator.itemgetter(1), servers)
ordered = sorted(numbers)
print(f'Ports open on {host}:', *format_ports(ordered), sep='\n ')
field_names = 'family', 'socket_type', 'protocol', 'canon_name', 'address'
AddressInfo = collections.namedtuple('AddressInfo', field_names)
del field_names
def test(address):
"""Try connecting to the server and return whether or not it succeeded."""
host, port = address
for info in itertools.starmap(AddressInfo, socket.getaddrinfo(host, port)):
try:
probe = socket.socket(info.family, info.socket_type, info.protocol)
except OSError:
pass
else:
try:
probe.connect(info.address)
except OSError:
pass
else:
probe.shutdown(socket.SHUT_RDWR)
return True, port
finally:
probe.close()
return False, port
def format_ports(ports):
"""Convert port numbers into strings and show all associated services."""
if ports:
for port in ports:
try:
service = socket.getservbyport(port)
except OSError:
service = '?'
yield f'{port:<5} = {service}'
else:
yield 'None'
if __name__ == '__main__':
main()
I've just finished tinkering with Concurrent Futures on a port scanner and by God it's fast:
import concurrent.futures
import socket
def scan_port(domainip: str, port: int) -> tuple:
try:
# Use a faster socket implementation
s = socket.create_connection((domainip, port), timeout=0.5)
# Check if the connection was successful
if s:
return (port, "open")
else:
return (port, "closed")
except Exception as e:
print(f"Error scanning port {port}: {e}")
return (port, "error")
openports = {}
# Scan the ports in parallel using the faster scanning code
with concurrent.futures.ThreadPoolExecutor() as executor:
futures = [executor.submit(scan_port, domainip, port) for port in range(1, 1024)]
for future in concurrent.futures.as_completed(futures):
status = future.result()
if status[1] == "open":
openports[status[0]] = status[1]
in my Proxy Project sometimes the Server process (given by teacher) ends with an error (a string beginning with 404) so I would like my thread, which had sent the requests, to stop and not to go on. I have tried with "return" or with "sys.exit()" but this seems to block everything and the Proxy stops receiving requests and creating threads. Why?
from socket import *
from threading import *
import sys
import colors
import os
import time
def startPrefetch(pagesToPrefetch, mutex):
for i in pagesToPrefetch:
print i
def receivePage(conn, addr, request, mutex):
HOSTSERVER = "127.0.0.1"
SERVERPORT = 55555
socketRequestServer = socket(AF_INET, SOCK_STREAM)
socketRequestServer.connect((HOSTSERVER, SERVERPORT))
socketRequestServer.send(request)
finalResponse = ''
while True:
partialResponse = socketRequestServer.recv(64)
if (not partialResponse): break
finalResponse = finalResponse+partialResponse
if (finalResponse[0] == '4'):
c = colors.colors()
print c.ERROR + finalResponse + "INTERNAL SERVER ERROR"
print c.WHITE
return
#sys.exit(1)
socketRequestServer.close()
conn.sendall(finalResponse)
conn.close()
pagesToPrefetch = []
sourceToString = finalResponse.split(' ')
for i in sourceToString:
if (len(i) != 0):
if (i[0] == '<'):
pagesToPrefetch.append(i)
startPrefetch(pagesToPrefetch, mutex)
if __name__ == '__main__':
HOST = '127.0.0.1'
PORT = 55554
print 'Creating socket'
socketProxy = socket(AF_INET, SOCK_STREAM)
print 'bind()'
socketProxy.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1)
socketProxy.bind((HOST, PORT))
#Cache directory and mutex for it
mutex = Semaphore(1)
try:
os.mkdir("cache")
except OSError:
print 'Created cache directory'
while True:
print 'Waiting for connection request'
socketProxy.listen(1)
conn, addr = socketProxy.accept()
print 'Connected to ', addr
request = conn.recv(512)
receiver = Thread(target = receivePage, args = (conn, addr, request, mutex))
receiver.start()
Using return is the correct way ( well, you should close connections before doing that, though ).
As David suggested this line:
request = conn.recv(512)
is probably the culprit. If the connection is made but no data is sent then the main thread will be locked. Not to mention that the request might be bigger then 512.
Move that line inside receivePage function ( and don't pass request to Thread constructor ) and let us know whether it works.