I recently bought the book Black Hat Python, 2nd Edition, by Justin Seitz, which seems to be a very good book about networking and all that (i am writing my code on Kali Linux)
I have a problem on the TCP Proxy Tool on chapter 2 :
Here is the code :
import sys
import socket
import threading
HEX_FILTER = ''.join(
[(len(repr(chr(i))) == 3) and chr(i) or '.' for i in range(256)])
def hexdump(src, length = 16, show = True):
# basically translates hexadecimal characters to readable ones
if isinstance(src, bytes):
src = src.decode()
results = list()
for i in range(0, len(src), length):
word = str(src[i:i+length])
printable = word.translate(HEX_FILTER)
hexa = ' '.join(['{ord(c):02X}' for c in word])
hexwidth = length*3
results.append('{i:04x} {hexa:<{hexwidth}} {printable}')
if show :
for line in results :
print(line)
else :
return results
def receive_from(connection):
buffer = b""
connection.settimeout(10)
try :
while True :
data = connection.recvfrom(4096)
if not data :
break
buffer += data
except Exception as e:
pass
return buffer
def request_handler(buffer):
# perform packet modifications
return buffer
def response_handler(buffer):
# perform packet modifications
return buffer
def proxy_handler(client_socket, remote_host, remote_port, receive_first):
remote_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
remote_socket.connect((remote_host, remote_port))
if receive_first :
# Check for any data to receive before
going into the main loop (i guess)
remote_buffer = receive_from(remote_socket)
hexdump(remote_buffer)
remote_buffer = response_handler(remote_buffer)
if len(remote_buffer):
print("[<==] Sending %d bytes to localhost." % len(remote_buffer))
client_socket.send(remote_buffer)
while True : # Start the loop
local_buffer = receive_from(client_socket)
if len(local_buffer):
line = "[==>] Received %d bytes from localhost." % len(local_buffer)
print(line)
hexdump(local_buffer)
local_buffer = request_handler(local_buffer)
remote_socket.send(local_buffer)
print("[==>] Sent to remote.")
remote_buffer = receive_from(remote_socket)
if len(remote_buffer):
print("[==>] Received %d bytes from remote." % len(remote_buffer))
hexdump(remote_buffer)
remote_buffer=response_handler(remote_buffer)
client_socket.send(remote_buffer)
print("[<==] Sent to localhost.")
if not len(local_buffer) or not len(remote_buffer):
# If no data is passed, close the sockets and breaks the loop
client_socket.close()
remote_socket.close()
print("[*] No more data. Closing connections. See you later !")
break
def server_loop(local_host, local_port, remote_host, remote_port, receive_first):
server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
try :
server.bind((local_host, local_port)) # Bind the local host and the local port
except Exception as e:
print('Problem on bind : %r' %e)
# If an error occurs, prints a
print("[!] Failed to listen on %s:%d" % (local_host, local_port))
print("[!] Check for other listening sockets or correct permissions.")
sys.exit(0)
print("[*] Listening on %s:%d" % (local_host, local_port))
server.listen(5)
while True :
client_socket, addr = server.accept()
# print out the local connection information
line = "> Received incoming connection from %s:%d" % (addr[0], addr[1])
print(line)
# start a thread to talk to the remote host
proxy_thread = threading.Thread(
target = proxy_handler,
args=(client_socket,remote_host,
remote_port, receive_first))
proxy_thread.start()
def main():
if len(sys.argv[1:]) != 5:
print("Usage: ./proxy.py [localhost] [localport]")
print("[remotehost] [remoteport] [receive_first]")
print("Example : ./proxy.py 127.0.0.1 9000 192.168.56.1 9000 True")
sys.exit(0)
loca l_host = sys.argv[1]
local_port = int(sys.argv[2])
remote_host = sys.argv[3]
remote_port = int(sys.argv[4])
receive_first = sys.argv[5]
if "True" in receive_first:
receive_first = True
else :
receive_first = False
server_loop(local_host, local_port,
remote_host, remote_port, receive_first)
if __name__ == '__main__':
main()
(sorry, i had a bit of a trouble formatting it and it's quite long)
Now, normally, i just need to open 2 terminals and run the code with the command line :
sudo python proxy.py 127.0.0.1 21 ftp.dlptest.com 21 True
in one terminal, and :
ftp 127.0.0.1 21
in the other one.
My code seems to be working fine, except that... I receive no data. I tried different ftp servers (notice that i don't use the one quoted in the book), but it still doesn't work. It just says :
[*] Listening on 127.0.0.1
> Received incoming connection from 127.0.0.1:55856
but it doesn't actually displays anything until the connexion times out or that i stop the command with Ctrl + C.
I know this question has already been asked, but they don't resolve my problem.
Please tell me if i forgot a line of code (for example the one that prints the data on the screen lol) or did anything wrong :)
one the hexa variable you need to put and f'{ord(c):02x}' because you just have a string and not using the 'c' variable from the list comprehension. That's a small typo you missed fix that and try the whole process again.
hexa = ' '.join([f'{ord(c):02X}' for c in word])
The f should be here ^
I'm working on a program that receives a string from an Android app sent through WiFi, the program was originally written for Python 2.7, but after adding some additional functionalities I changed it to Python 3.7. However, after making that change, my data had an extra letter at the front and for the life of me I can't figure out why that is.
Here's a snippet of my code, it's a really simple if statement to see which command was sent from the Android app and controls Raspberry Pi (4) cam (v.2) with the command.
This part sets up the connections and wait to see which command I send.
isoCmd = ['auto','100','200','300','400','500','640','800']
HOST = ''
PORT = 21567
BUFSIZE = 1024
ADDR = (HOST,PORT)
brightness = 50
timelapse = 0
tcpSerSock = socket(AF_INET, SOCK_STREAM)
tcpSerSock.bind(ADDR)
tcpSerSock.listen(5)
while True:
print ('Waiting for connection')
tcpCliSock,addr = tcpSerSock.accept()
try:
while True:
data = ''
brightness = ' '
data = tcpCliSock.recv(BUFSIZE)
dataStr = str(data[1:])
print ("Here's data ",dataStr)
if not data:
break
if data in isoCmd:
if data == "auto":
camera.iso = 0
print ('ISO: Auto')
else:
camera.iso = int(data)
print ('ISO: '), data
When I start the program this is what I see:
Waiting for connection
#If I send command '300'
Here's data b'300'
Here's data b''
Waiting for connection
I'm not sure why there's the extra b'' is coming from. I have tested the code by just adding the "b" at the beginning of each items in the array which worked for any commands that I defined, not for any commands to control the Pi camera since well, there's no extra b at the beginning. (Did that make sense?) My point is, I know I'm able to send commands no problem, just not sure how to get rid of the extra letter. If anyone could give me some advice that would be great. Thanks for helping.
Byte strings are represented by the b-prefix.
Although you can see the string in output on printing, inherently they are bytes.
To get a normal string out of it, decode function can help.
dataStr.decode("utf-8")
b'data' simply means the data inside quotes has been received in bytes form, as mentioned in other answers also, you have to decode that with decode('utf-8') to get it in string form.
I have updated your program below, to be compatible for v3.7+
from socket import *
isoCmd = ['auto','100','200','300','400','500','640','800']
HOST = ''
PORT = 21567
BUFSIZE = 1024
ADDR = (HOST,PORT)
brightness = 50
timelapse = 0
tcpSerSock = socket(AF_INET, SOCK_STREAM)
tcpSerSock.bind(ADDR)
tcpSerSock.listen(5)
while True:
print ('Waiting for connection')
tcpCliSock,addr = tcpSerSock.accept()
try:
while True:
data = ''
brightness = ' '
data = tcpCliSock.recv(BUFSIZE).decode('utf-8')
print ("Here's data "+data)
if not data:
break
if data in isoCmd:
if data == "auto":
camera.iso = 0
print ('ISO: Auto')
else:
camera.iso = int(data)
print ('ISO: '+ data)
except Exception as e:
print(e)
The main issue
In a nutshell: I want two consoles for my programm. One for active user input. And the other one for pure log output. (Working code including the accepted answer is in the question's text below, under section "Edit-3". And under section "Edit-1" and section "Edit-2" are functioning workarounds.)
For this I have a main command line Python script, which is supposed to open an additional console for log output only. For this I intend to redirect the log output, which would be printed on the main script's console, to the stdin of the second console, which I start as a subprocess. (I use subprocess, because I didn't find any other way to open a second console.)
The problem is, that it seems that I'm able to send to the stdin of this second console - however, nothing gets printed on this second console.
Following is the code I used for experimenting (with Python 3.4 on PyDev under Windows 10). The function writing(input, pipe, process) contains the part, where the generated string is copied to the as pipe passed stdin, of the via subprocess opened console. The function writing(...) is run via the class writetest(Thread). (I left some code, which I commented out.)
import os
import sys
import io
import time
import threading
from cmd import Cmd
from queue import Queue
from subprocess import Popen, PIPE, CREATE_NEW_CONSOLE
REPETITIONS = 3
# Position of "The class" (Edit-2)
# Position of "The class" (Edit-1)
class generatetest(threading.Thread):
def __init__(self, queue):
self.output = queue
threading.Thread.__init__(self)
def run(self):
print('run generatetest')
generating(REPETITIONS, self.output)
print('generatetest done')
def getout(self):
return self.output
class writetest(threading.Thread):
def __init__(self, input=None, pipe=None, process=None):
if (input == None): # just in case
self.input = Queue()
else:
self.input = input
if (pipe == None): # just in case
self.pipe = PIPE
else:
self.pipe = pipe
if (process == None): # just in case
self.process = subprocess.Popen('C:\Windows\System32\cmd.exe', universal_newlines=True, creationflags=CREATE_NEW_CONSOLE)
else:
self.process = proc
threading.Thread.__init__(self)
def run(self):
print('run writetest')
writing(self.input, self.pipe, self.process)
print('writetest done')
# Position of "The function" (Edit-2)
# Position of "The function" (Edit-1)
def generating(maxint, outline):
print('def generating')
for i in range(maxint):
time.sleep(1)
outline.put_nowait(i)
def writing(input, pipe, process):
print('def writing')
while(True):
try:
print('try')
string = str(input.get(True, REPETITIONS)) + "\n"
pipe = io.StringIO(string)
pipe.flush()
time.sleep(1)
# print(pipe.readline())
except:
print('except')
break
finally:
print('finally')
pass
data_queue = Queue()
data_pipe = sys.stdin
# printer = sys.stdout
# data_pipe = os.pipe()[1]
# The code of 'C:\\Users\\Public\\Documents\\test\\test-cmd.py'
# can be found in the question's text further below under "More code"
exe = 'C:\Python34\python.exe'
# exe = 'C:\Windows\System32\cmd.exe'
arg = 'C:\\Users\\Public\\Documents\\test\\test-cmd.py'
arguments = [exe, arg]
# proc = Popen(arguments, universal_newlines=True, creationflags=CREATE_NEW_CONSOLE)
proc = Popen(arguments, stdin=data_pipe, stdout=PIPE, stderr=PIPE,
universal_newlines=True, creationflags=CREATE_NEW_CONSOLE)
# Position of "The call" (Edit-2 & Edit-1) - file init (proxyfile)
# Position of "The call" (Edit-2) - thread = sockettest()
# Position of "The call" (Edit-1) - thread0 = logtest()
thread1 = generatetest(data_queue)
thread2 = writetest(data_queue, data_pipe, proc)
# time.sleep(5)
# Position of "The call" (Edit-2) - thread.start()
# Position of "The call" (Edit-1) - thread0.start()
thread1.start()
thread2.start()
# Position of "The call" (Edit-2) - thread.join()
# Position of "The call" (Edit-1) - thread.join()
thread1.join(REPETITIONS * REPETITIONS)
thread2.join(REPETITIONS * REPETITIONS)
# data_queue.join()
# receiver = proc.communicate(stdin, 5)
# print('OUT:' + receiver[0])
# print('ERR:' + receiver[1])
print("1st part finished")
A slightly different approach
The following additional code snippet works in regard to extracting the stdout from the subprocess. However, the previously sent stdin still isn't print on the second console. Also, the second console is closed immediately.
proc2 = Popen(['C:\Python34\python.exe', '-i'],
stdin=PIPE,
stdout=PIPE,
stderr=PIPE,
creationflags=CREATE_NEW_CONSOLE)
proc2.stdin.write(b'2+2\n')
proc2.stdin.flush()
print(proc2.stdout.readline())
proc2.stdin.write(b'len("foobar")\n')
proc2.stdin.flush()
print(proc2.stdout.readline())
time.sleep(1)
proc2.stdin.close()
proc2.terminate()
proc2.wait(timeout=0.2)
print("Exiting Main Thread")
More info
As soon as I use one of the paramaters stdin=data_pipe, stdout=PIPE, stderr=PIPE for starting the subprocess, the resulting second console isn't active and doesn't accept keyboard input (which isn't desired, though might be helpful information here).
The subprocess method communicate() can't be used for this as it waits for the process to end.
More code
Finally the code for the file, which is for the second console.
C:\Users\Public\Documents\test\test-cmd.py
from cmd import Cmd
from time import sleep
from datetime import datetime
INTRO = 'command line'
PROMPT = '> '
class CommandLine(Cmd):
"""Custom console"""
def __init__(self, intro=INTRO, prompt=PROMPT):
Cmd.__init__(self)
self.intro = intro
self.prompt = prompt
self.doc_header = intro
self.running = False
def do_dummy(self, args):
"""Runs a dummy method."""
print("Do the dummy.")
self.running = True
while(self.running == True):
print(datetime.now())
sleep(5)
def do_stop(self, args):
"""Stops the dummy method."""
print("Stop the dummy, if you can.")
self.running = False
def do_exit(self, args):
"""Exits this console."""
print("Do console exit.")
exit()
if __name__ == '__main__':
cl = CommandLine()
cl.prompt = PROMPT
cl.cmdloop(INTRO)
Thoughts
So far I'm even not certain if the Windows command line interface offers the capability to accept other input than the one from the keyboard (instead of the desired stdin pipe or similar). Though, with it having some sort of passive mode, I expect it.
Why is this not working?
Edit-1: Workaround via file (proof of concept)
Using a file as workaround in order display it's new content, as suggested in the answer of Working multiple consoles in python, is working in general. However, since the log file will grow up to many GB, it isn't a practical solution in this case. It would at least require file splitting and the proper handling of it.
The class:
class logtest(threading.Thread):
def __init__(self, file):
self.file = file
threading.Thread.__init__(self)
def run(self):
print('run logtest')
logging(self.file)
print('logtest done')
The function:
def logging(file):
pexe = 'C:\Python34\python.exe '
script = 'C:\\Users\\Public\\Documents\\test\\test-004.py'
filek = '--file'
filev = file
file = open(file, 'a')
file.close()
time.sleep(1)
print('LOG START (outer): ' + script + ' ' + filek + ' ' + filev)
proc = Popen([pexe, script, filek, filev], universal_newlines=True, creationflags=CREATE_NEW_CONSOLE)
print('LOG FINISH (outer): ' + script + ' ' + filek + ' ' + filev)
time.sleep(2)
The call:
# The file tempdata is filled with several strings of "0\n1\n2\n"
# Looking like this:
# 0
# 1
# 2
# 0
# 1
# 2
proxyfile = 'C:\\Users\\Public\\Documents\\test\\tempdata'
f = open(proxyfile, 'a')
f.close()
time.sleep(1)
thread0 = logtest(proxyfile)
thread0.start()
thread0.join(REPETITIONS * REPETITIONS)
The tail script ("test-004.py"):
As Windows doesn't offer the tail command, I used the following script instead (base on the answer for How to implement a pythonic equivalent of tail -F?), which worked for this. The additional, yet kind of unnecessary class CommandLine(Cmd) was initially an attempt to keep the second console open (because the script file argument was missing). Though, it also proved itself as useful for keeping the console fluently printing the new log file content. Otherwise the output wasn't deterministic/predictable.
import time
import sys
import os
import threading
from cmd import Cmd
from argparse import ArgumentParser
def main(args):
parser = ArgumentParser(description="Parse arguments.")
parser.add_argument("-f", "--file", type=str, default='', required=False)
arguments = parser.parse_args(args)
if not arguments.file:
print('LOG PRE-START (inner): file argument not found. Creating new default entry.')
arguments.file = 'C:\\Users\\Public\\Documents\\test\\tempdata'
print('LOG START (inner): ' + os.path.abspath(os.path.dirname(__file__)) + ' ' + arguments.file)
f = open(arguments.file, 'a')
f.close()
time.sleep(1)
words = ['word']
console = CommandLine(arguments.file, words)
console.prompt = ''
thread = threading.Thread(target=console.cmdloop, args=('', ))
thread.start()
print("\n")
for hit_word, hit_sentence in console.watch():
print("Found %r in line: %r" % (hit_word, hit_sentence))
print('LOG FINISH (inner): ' + os.path.abspath(os.path.dirname(__file__)) + ' ' + arguments.file)
class CommandLine(Cmd):
"""Custom console"""
def __init__(self, fn, words):
Cmd.__init__(self)
self.fn = fn
self.words = words
def watch(self):
fp = open(self.fn, 'r')
while True:
time.sleep(0.05)
new = fp.readline()
print(new)
# Once all lines are read this just returns ''
# until the file changes and a new line appears
if new:
for word in self.words:
if word in new:
yield (word, new)
else:
time.sleep(0.5)
if __name__ == '__main__':
print('LOG START (inner - as main).')
main(sys.argv[1:])
Edit-1: More thoughts
Three workarounds, which I didn't try yet and might work are sockets (also suggested in this answer Working multiple consoles in python), getting a process object via the process ID for more control, and using the ctypes library for directly accessing the Windows console API, allowing to set the screen buffer, as the console can have multiple buffers, but only one active buffer (stated in the remarks of the documentation for the CreateConsoleScreenBuffer function).
However, using sockets might be the easiest one. And at least the size of the log doesn't matter this way. Though, connection problems might be a problem here.
Edit-2: Workaround via sockets (proof of concept)
Using sockets as workaround in order display new log enties, as it also was suggested in the answer of Working multiple consoles in python, is working in general, too. Though, this seems to be too much effort for something, which should be simply sent to the process of the receiving console.
The class:
class sockettest(threading.Thread):
def __init__(self, host, port, file):
self.host = host
self.port = port
self.file = file
threading.Thread.__init__(self)
def run(self):
print('run sockettest')
socketing(self.host, self.port, self.file)
print('sockettest done')
The function:
def socketing(host, port, file):
pexe = 'C:\Python34\python.exe '
script = 'C:\\Users\\Public\\Documents\\test\test-005.py'
hostk = '--address'
hostv = str(host)
portk = '--port'
portv = str(port)
filek = '--file'
filev = file
file = open(file, 'a')
file.close()
time.sleep(1)
print('HOST START (outer): ' + pexe + script + ' ' + hostk + ' ' + hostv + ' ' + portk + ' ' + portv + ' ' + filek + ' ' + filev)
proc = Popen([pexe, script, hostk, hostv, portk, portv, filek, filev], universal_newlines=True, creationflags=CREATE_NEW_CONSOLE)
print('HOST FINISH (outer): ' + pexe + script + ' ' + hostk + ' ' + hostv + ' ' + portk + ' ' + portv + ' ' + filek + ' ' + filev)
time.sleep(2)
The call:
# The file tempdata is filled with several strings of "0\n1\n2\n"
# Looking like this:
# 0
# 1
# 2
# 0
# 1
# 2
proxyfile = 'C:\\Users\\Public\\Documents\\test\\tempdata'
f = open(proxyfile, 'a')
f.close()
time.sleep(1)
thread = sockettest('127.0.0.1', 8888, proxyfile)
thread.start()
thread.join(REPETITIONS * REPETITIONS)
The socket script ("test-005.py"):
The following script is based on Python: Socket programming server-client application using threads. Here I just keept the class CommandLine(Cmd) as log entry generator. At this point it should't be a problem, to put client into the main script, which calls the second console and then feed the queue with real log enties instead of (new) file lines. (The server is the printer.)
import socket
import sys
import threading
import time
from cmd import Cmd
from argparse import ArgumentParser
from queue import Queue
BUFFER_SIZE = 5120
class CommandLine(Cmd):
"""Custom console"""
def __init__(self, fn, words, queue):
Cmd.__init__(self)
self.fn = fn
self.words = words
self.queue = queue
def watch(self):
fp = open(self.fn, 'r')
while True:
time.sleep(0.05)
new = fp.readline()
# Once all lines are read this just returns ''
# until the file changes and a new line appears
self.queue.put_nowait(new)
def main(args):
parser = ArgumentParser(description="Parse arguments.")
parser.add_argument("-a", "--address", type=str, default='127.0.0.1', required=False)
parser.add_argument("-p", "--port", type=str, default='8888', required=False)
parser.add_argument("-f", "--file", type=str, default='', required=False)
arguments = parser.parse_args(args)
if not arguments.address:
print('HOST PRE-START (inner): host argument not found. Creating new default entry.')
arguments.host = '127.0.0.1'
if not arguments.port:
print('HOST PRE-START (inner): port argument not found. Creating new default entry.')
arguments.port = '8888'
if not arguments.file:
print('HOST PRE-START (inner): file argument not found. Creating new default entry.')
arguments.file = 'C:\\Users\\Public\\Documents\\test\\tempdata'
file_queue = Queue()
print('HOST START (inner): ' + ' ' + arguments.address + ':' + arguments.port + ' --file ' + arguments.file)
# Start server
thread = threading.Thread(target=start_server, args=(arguments.address, arguments.port, ))
thread.start()
time.sleep(1)
# Start client
thread = threading.Thread(target=start_client, args=(arguments.address, arguments.port, file_queue, ))
thread.start()
# Start file reader
f = open(arguments.file, 'a')
f.close()
time.sleep(1)
words = ['word']
console = CommandLine(arguments.file, words, file_queue)
console.prompt = ''
thread = threading.Thread(target=console.cmdloop, args=('', ))
thread.start()
print("\n")
for hit_word, hit_sentence in console.watch():
print("Found %r in line: %r" % (hit_word, hit_sentence))
print('HOST FINISH (inner): ' + ' ' + arguments.address + ':' + arguments.port)
def start_client(host, port, queue):
host = host
port = int(port) # arbitrary non-privileged port
queue = queue
soc = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
try:
soc.connect((host, port))
except:
print("Client connection error" + str(sys.exc_info()))
sys.exit()
print("Enter 'quit' to exit")
message = ""
while message != 'quit':
time.sleep(0.05)
if(message != ""):
soc.sendall(message.encode("utf8"))
if soc.recv(BUFFER_SIZE).decode("utf8") == "-":
pass # null operation
string = ""
if (not queue.empty()):
string = str(queue.get_nowait()) + "\n"
if(string == None or string == ""):
message = ""
else:
message = string
soc.send(b'--quit--')
def start_server(host, port):
host = host
port = int(port) # arbitrary non-privileged port
soc = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
# SO_REUSEADDR flag tells the kernel to reuse a local socket in TIME_WAIT state, without waiting for its natural timeout to expire
soc.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
print("Socket created")
try:
soc.bind((host, port))
except:
print("Bind failed. Error : " + str(sys.exc_info()))
sys.exit()
soc.listen(5) # queue up to 5 requests
print("Socket now listening")
# infinite loop- do not reset for every requests
while True:
connection, address = soc.accept()
ip, port = str(address[0]), str(address[1])
print("Connected with " + ip + ":" + port)
try:
threading.Thread(target=client_thread, args=(connection, ip, port)).start()
except:
print("Thread did not start.")
traceback.print_exc()
soc.close()
def client_thread(connection, ip, port, max_buffer_size=BUFFER_SIZE):
is_active = True
while is_active:
client_input = receive_input(connection, max_buffer_size)
if "--QUIT--" in client_input:
print("Client is requesting to quit")
connection.close()
print("Connection " + ip + ":" + port + " closed")
is_active = False
elif not client_input == "":
print("{}".format(client_input))
connection.sendall("-".encode("utf8"))
else:
connection.sendall("-".encode("utf8"))
def receive_input(connection, max_buffer_size):
client_input = connection.recv(max_buffer_size)
client_input_size = sys.getsizeof(client_input)
if client_input_size > max_buffer_size:
print("The input size is greater than expected {}".format(client_input_size))
decoded_input = client_input.decode("utf8").rstrip() # decode and strip end of line
result = process_input(decoded_input)
return result
def process_input(input_str):
return str(input_str).upper()
if __name__ == '__main__':
print('HOST START (inner - as main).')
main(sys.argv[1:])
Edit-2: Furthermore thoughts
Having direct control of the subprocess' console input pipe/buffer would be the preferable solution to this problem. For this is the bounty of 500 Reputation.
Unfortunately I'm running out of time. Therefore I might use one of those workarounds for now and replace them with the proper solution later. Or maybe I have to use the nuclear option, just one console, where the ongoing log output is paused during any user keyboard input, and printed afterwards. Of course this might lead to buffer problems, when the user decides to type something just half the way.
Edit-3: Code including the accepted answer (one file)
With the answer from James Kent I get the desired behavior, when I start a script with the code via the Windows command line (cmd) or PowerShell. However, when I start this same script via Eclipse/PyDev with "Python run", then the output is always printed on the main Eclipse/PyDev console, while the second console of the subprocess remains empty and stays inactive. Though, I guess this is another system/environment speciality and a different issue.
from sys import argv, stdin, stdout
from threading import Thread
from cmd import Cmd
from time import sleep
from datetime import datetime
from subprocess import Popen, PIPE, CREATE_NEW_CONSOLE
INTRO = 'command line'
PROMPT = '> '
class CommandLine(Cmd):
"""Custom console"""
def __init__(self, subprocess, intro=INTRO, prompt=PROMPT):
Cmd.__init__(self)
self.subprocess = subprocess
self.intro = intro
self.prompt = prompt
self.doc_header = intro
self.running = False
def do_date(self, args):
"""Prints the current date and time."""
print(datetime.now())
sleep(1)
def do_exit(self, args):
"""Exits this command line application."""
print("Exit by user command.")
if self.subprocess is not None:
try:
self.subprocess.terminate()
except:
self.subprocess.kill()
exit()
class Console():
def __init__(self):
if '-r' not in argv:
self.p = Popen(
['python.exe', __file__, '-r'],
stdin=PIPE,
creationflags=CREATE_NEW_CONSOLE
)
else:
while True:
data = stdin.read(1)
if not data:
# break
sleep(1)
continue
stdout.write(data)
def write(self, data):
self.p.stdin.write(data.encode('utf8'))
self.p.stdin.flush()
def getSubprocess(self):
if self.p:
return self.p
else:
return None
class Feeder (Thread):
def __init__(self, console):
self.console = console
Thread.__init__(self)
def run(self):
feeding(self.console)
def feeding(console):
for i in range(0, 100):
console.write('test %i\n' % i)
sleep(1)
if __name__ == '__main__':
p = Console()
if '-r' not in argv:
thread = Feeder(p)
thread.setDaemon(True)
thread.start()
cl = CommandLine(subprocess=p.getSubprocess())
cl.use_rawinput = False
cl.prompt = PROMPT
cl.cmdloop('\nCommand line is waiting for user input (e.g. help).')
Edit-3: Honorable mentions
In the questions's text above I have mentioned using the ctypes library for directly accessing the Windows console API as another workround (under "Edit-1: More thoughts"). Or using just one console in a way, that the input prompt always stays at the bottom as nuclear option to this entire problem. (under "Edit-2: Furthermore thoughts")
For using the ctypes library I would have oriented myself on the following answer to Change console font in Windows. And for using just one console I would have tried the following answer to Keep console input line below output. I think both of these answers may offer potential merrit regarding this problem and maybe they are helpful to others how come accross this post. Also, I if i find the time, I will try if they work somehow.
The issue you're up against is the architecture of the console subsystem on Windows, the console window that you normally see is not hosted by cmd.exe but instead by conhost.exe, a child process of a conhost window can only connect to a single conhost instance meaning you're limited to a single window per process.
This then leads on to having an extra process for each console window you wish to have, then in order to look at displaying anything in that window you need to look at how stdin and stdout are normally handled, in that they are written and read from by the conhost instance, except if you turn stdin into a pipe (so you can write to the process) it no longer comes from conhost but instead from your parent process and as such conhost has no visibility of it. This means that anything written to stdin is only read by the child process so is not displayed by conhost.
As far as I know there isn't a way to share the pipe like that.
As a side effect if you make stdin a pipe then all keyboard input sent to the new console window goes nowhere, as stdin is not connected to that window.
For an output only function this means you can spawn a new process that communicates with the parent via a pipe to stdin and echos everything to stdout.
Heres an attempt:
#!python3
import sys, subprocess, time
class Console():
def __init__(self):
if '-r' not in sys.argv:
self.p = subprocess.Popen(
['python.exe', __file__, '-r'],
stdin=subprocess.PIPE,
creationflags=subprocess.CREATE_NEW_CONSOLE
)
else:
while True:
data = sys.stdin.read(1)
if not data:
break
sys.stdout.write(data)
def write(self, data):
self.p.stdin.write(data.encode('utf8'))
self.p.stdin.flush()
if (__name__ == '__main__'):
p = Console()
if '-r' not in sys.argv:
for i in range(0, 100):
p.write('test %i\n' % i)
time.sleep(1)
So a nice simple pipe between two processes and echoing the input back to the output if its the subprocess, I used a -r to signify whether the instance is a process but there are other ways depending on how you implement it.
Several things to note:
the flush after writing to stdin is needed as python normally uses buffering.
the way this approach is written is aimed at being in its own module hence the use of __file__
due to the use of __file__ this approach may need modification if frozen using cx_Freeze or similar.
EDIT 1
for a version that can be frozen with cx_Freeze:
Console.py
import sys, subprocess
class Console():
def __init__(self, ischild=True):
if not ischild:
if hasattr(sys, 'frozen'):
args = ['Console.exe']
else:
args = [sys.executable, __file__]
self.p = subprocess.Popen(
args,
stdin=subprocess.PIPE,
creationflags=subprocess.CREATE_NEW_CONSOLE
)
else:
while True:
data = sys.stdin.read(1)
if not data:
break
sys.stdout.write(data)
def write(self, data):
self.p.stdin.write(data.encode('utf8'))
self.p.stdin.flush()
if (__name__ == '__main__'):
p = Console()
test.py
from Console import Console
import sys, time
if (__name__ == '__main__'):
p = Console(False)
for i in range(0, 100):
p.write('test %i\n' % i)
time.sleep(1)
setup.py
from cx_Freeze import setup, Executable
setup(
name = 'Console-test',
executables = [
Executable(
'Console.py',
base=None,
),
Executable(
'test.py',
base=None,
)
]
)
EDIT 2
New version that should work under dev tools like IDLE
Console.py
#!python3
import ctypes, sys, subprocess
Kernel32 = ctypes.windll.Kernel32
class Console():
def __init__(self, ischild=True):
if ischild:
# try allocate new console
result = Kernel32.AllocConsole()
if result > 0:
# if we succeed open handle to the console output
sys.stdout = open('CONOUT$', mode='w')
else:
# if frozen we assume its names Console.exe
# note that when frozen 'Win32GUI' must be used as a base
if hasattr(sys, 'frozen'):
args = ['Console.exe']
else:
# otherwise we use the console free version of python
args = ['pythonw.exe', __file__]
self.p = subprocess.Popen(
args,
stdin=subprocess.PIPE
)
return
while True:
data = sys.stdin.read(1)
if not data:
break
sys.stdout.write(data)
def write(self, data):
self.p.stdin.write(data.encode('utf8'))
self.p.stdin.flush()
if (__name__ == '__main__'):
p = Console()
test.py
from Console import Console
import sys, time
if (__name__ == '__main__'):
p = Console(False)
for i in range(0, 100):
p.write('test %i\n' % i)
time.sleep(1)
setup.py
from cx_Freeze import setup, Executable
setup(
name = 'Console-test',
executables = [
Executable(
'Console.py',
base='Win32GUI',
),
Executable(
'test.py',
base=None,
)
]
)
This could be made more robust, i.e. always checking for an existing console and detaching it if found before creating a new console, and possibly better error handling.
Since you are on windows you can use win32console module to open a second console or multiple consoles for your thread or subprocess output. This is the most simple and easiest way that works if you are on windows.
Here is a sample code:
import win32console
import multiprocessing
def subprocess(queue):
win32console.FreeConsole() #Frees subprocess from using main console
win32console.AllocConsole() #Creates new console and all input and output of subprocess goes to this new console
while True:
print(queue.get())
#prints any output produced by main script passed to subprocess using queue
if __name__ == "__main__":
queue = multiprocessing.Queue()
multiprocessing.Process(target=subprocess, args=[queue]).start()
while True:
print("Hello World in main console")
queue.put("Hello work in sub process console")
#sends above string to subprocess and it prints it into its console
#and whatever else you want to do in ur main process
You can also do this with threading. You have to use queue module if you want the queue functionality as threading module doesn't have queue
Here is the win32console module documentation
How can I find with scapy wireless networks around? If I do sniff() and if pkt.haslayer(Dot11) and then if pkt.info then I collect them but very slow, for example my Android phone do it in seconds and this script in minutes or even more...
The reason for the difference is that your phone is actively looking for WiFi points by sending out requests to any access points nearby - sniff is listening for any passing traffic.
You might find is a lot quicker to:
Specifically select your network adapter - so you are not sniffing all adapters.
Do some digging to find out how to actively query for wifi networks and use sr with such packets, read the IEEE 802.11 specification to find out more, I would especially look for "Probe request frame".
The example on how to send WiFi packets from packet header may well help, (not my code and not tested by me):
#!/usr/bin/env python
"""
802.11 Scapy Packet Example
Author: Joff Thyer, 2014
"""
# if we set logging to ERROR level, it supresses the warning message
# from Scapy about ipv6 routing
# WARNING: No route found for IPv6 destination :: (no default route?)
import logging
logging.getLogger("scapy.runtime").setLevel(logging.ERROR)
from scapy.all import *
class Scapy80211():
def __init__(self,intf='wlan0',ssid='test',\
source='00:00:de:ad:be:ef',\
bssid='00:11:22:33:44:55',srcip='10.10.10.10'):
self.rates = "\x03\x12\x96\x18\x24\x30\x48\x60"
self.ssid = ssid
self.source = source
self.srcip = srcip
self.bssid = bssid
self.intf = intf
self.intfmon = intf + 'mon'
# set Scapy conf.iface
conf.iface = self.intfmon
# create monitor interface using iw
cmd = '/sbin/iw dev %s interface add %s type monitor >/dev/null 2>&1' \
% (self.intf, self.intfmon)
try:
os.system(cmd)
except:
raise
def Beacon(self,count=10,ssid='',dst='ff:ff:ff:ff:ff:ff'):
if not ssid: ssid=self.ssid
beacon = Dot11Beacon(cap=0x2104)
essid = Dot11Elt(ID='SSID',info=ssid)
rates = Dot11Elt(ID='Rates',info=self.rates)
dsset = Dot11Elt(ID='DSset',info='\x01')
tim = Dot11Elt(ID='TIM',info='\x00\x01\x00\x00')
pkt = RadioTap()\
/Dot11(type=0,subtype=8,addr1=dst,addr2=self.source,addr3=self.bssid)\
/beacon/essid/rates/dsset/tim
print '[*] 802.11 Beacon: SSID=[%s], count=%d' % (ssid,count)
try:
sendp(pkt,iface=self.intfmon,count=count,inter=0.1,verbose=0)
except:
raise
def ProbeReq(self,count=10,ssid='',dst='ff:ff:ff:ff:ff:ff'):
if not ssid: ssid=self.ssid
param = Dot11ProbeReq()
essid = Dot11Elt(ID='SSID',info=ssid)
rates = Dot11Elt(ID='Rates',info=self.rates)
dsset = Dot11Elt(ID='DSset',info='\x01')
pkt = RadioTap()\
/Dot11(type=0,subtype=4,addr1=dst,addr2=self.source,addr3=self.bssid)\
/param/essid/rates/dsset
print '[*] 802.11 Probe Request: SSID=[%s], count=%d' % (ssid,count)
try:
sendp(pkt,count=count,inter=0.1,verbose=0)
except:
raise
def ARP(self,targetip,count=1,toDS=False):
if not targetip: return
arp = LLC()/SNAP()/ARP(op='who-has',psrc=self.srcip,pdst=targetip,hwsrc=self.source)
if toDS:
pkt = RadioTap()\
/Dot11(type=2,subtype=32,FCfield='to-DS',\
addr1=self.bssid,addr2=self.source,addr3='ff:ff:ff:ff:ff:ff')\
/arp
else:
pkt = RadioTap()\
/Dot11(type=2,subtype=32,\
addr1='ff:ff:ff:ff:ff:ff',addr2=self.source,addr3=self.bssid)\
/arp
print '[*] ARP Req: who-has %s' % (targetip)
try:
sendp(pkt,inter=0.1,verbose=0,count=count)
except:
raise
ans = sniff(lfilter = lambda x: x.haslayer(ARP) and x.op == 2,
store=1,count=1,timeout=1)
if len(ans) > 0:
return ans[0][ARP].hwsrc
else:
return None
def DNSQuery(self,query='www.google.com',qtype='A',ns=None,count=1,toDS=False):
if ns == None: return
dstmac = self.ARP(ns)
dns = LLC()/SNAP()/IP(src=self.srcip,dst=ns)/\
UDP(sport=random.randint(49152,65535),dport=53)/\
DNS(qd=DNSQR(qname=query,qtype=qtype))
if toDS:
pkt = RadioTap()\
/Dot11(type=2,subtype=32,FCfield='to-DS',\
addr1=self.bssid,addr2=self.source,addr3=dstmac)/dns
else:
pkt = RadioTap()\
/Dot11(type=2,subtype=32,\
addr1=dstmac,addr2=self.source,addr3=self.bssid)/dns
print '[*] DNS query %s (%s) -> %s?' % (query,qtype,ns)
try:
sendp(pkt,count=count,verbose=0)
except:
raise
# main routine
if __name__ == "__main__":
print """
[*] 802.11 Scapy Packet Crafting Example
[*] Assumes 'wlan0' is your wireless NIC!
[*] Author: Joff Thyer, 2014
"""
sdot11 = Scapy80211(intf='wlan0')
sdot11.Beacon()
sdot11.ProbeReq()
sdot11.DNSQuery(ns='10.10.10.2')
I once wrote a script that could scan wireless network .
Its simple to use :
python rs.py mon0
Here mon0 is our interface. There are comments in the code to understand it properly.
#Implementation of a wireless scanner using Scapy library
#!/usr/bin/env python
# rs.py - Wireless AP scanner
#author rahil sharma
# date 15/3/2013 #rs
#usage python rs.py mon0
#where mon0 is your monitoring interface
#used this using my alfa card in bactrack
import sys, os, signal
from multiprocessing import Process
from scapy.all import *
interface='' # monitor interface
aps = {} # dictionary to store unique APs
# process unique sniffed Beacons and ProbeResponses.
#haslayer packet has Dot11 layer present
#ord() string to integer ex ord('a) will give 97
def sniffAP(p):
if ( (p.haslayer(Dot11Beacon))):
ssid = p[Dot11Elt].info
bssid = p[Dot11].addr3
channel = int( ord(p[Dot11Elt:3].info))
capability = p.sprintf("{Dot11Beacon:%Dot11Beacon.cap%}\
{Dot11ProbeResp:%Dot11ProbeResp.cap%}")
# Check for encrypted networks
#now we put Dot11Beacon.cap info in capability and using regular expression search inbuilt function in python we search for privacy if it is present then the network is encrypted
#output of the above cap file is somewhat like this short-slot+DSSS-OFDM+res15+ESS
if re.search("privacy", capability): enc = 'Y'
else: enc = 'N'
# Save discovered AP
aps[p[Dot11].addr3] = enc
# Display discovered AP
print "%02d %s %s %s" % (int(channel), enc, bssid, ssid)
# Channel hopper - we are making a channel hopper because we want to scan the whole wireless spectrum.
#first choose a random channel using randrange function
#use system to run the shell command iw dev wlan0 set channel 1
#exit when a keyboard interrupt is given CTrl+c
def channel_hopper():
while True:
try:
channel = random.randrange(1,15)
os.system("iw dev %s set channel %d" % (interface, channel))
time.sleep(1)
except KeyboardInterrupt:
break
# Capture interrupt signal and cleanup before exiting
#terminate is used to end the child process
#before exiting the program we will be displaying number of aps found etc.
#here Cntrl+c is used to
#signal_handler used to do clean up before the program exits
def signal_handler(signal, frame):
p.terminate()
p.join()
print "\n-=-=-=-=-= STATISTICS =-=-=-=-=-=-"
print "Total APs found: %d" % len(aps)
print "Encrypted APs : %d" % len([ap for ap in aps if aps[ap] =='Y'])
print "Unencrypted APs: %d" % len([ap for ap in aps if aps[ap] =='N'])
sys.exit(0)
#use this for command line variables
#for checking the number of command line variables and if they are in right order
if __name__ == "__main__":
if len(sys.argv) != 2:
print "Usage %s monitor_interface" % sys.argv[0]
sys.exit(1)
interface = sys.argv[1]
#take mon0 as interface given in the fist command line variable
# Print the program header
print "-=-=-=-=-=-= rs_scan.py =-=-=-=-=-=-"
print "CH ENC BSSID SSID"
# Start the channel hopper
#In multiprocessing, processes are spawned by creating a Process object and then calling its start() method
p = Process(target = channel_hopper)
p.start()
# Capture CTRL-C
#this will call the signal handler CTRL+C comes under the SIGINT
signal.signal(signal.SIGINT, signal_handler)
# Start the sniffer
sniff(iface=interface,prn=sniffAP)
#inbuit scapy function to start sniffing calls a function which defines the criteria and we need to give the interface`enter code here`