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@leonjza
Last active May 15, 2022
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Python Netcat
import socket
class Netcat:
""" Python 'netcat like' module """
def __init__(self, ip, port):
self.buff = ""
self.socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.socket.connect((ip, port))
def read(self, length = 1024):
""" Read 1024 bytes off the socket """
return self.socket.recv(length)
def read_until(self, data):
""" Read data into the buffer until we have data """
while not data in self.buff:
self.buff += self.socket.recv(1024)
pos = self.buff.find(data)
rval = self.buff[:pos + len(data)]
self.buff = self.buff[pos + len(data):]
return rval
def write(self, data):
self.socket.send(data)
def close(self):
self.socket.close()
# below is a extract from a sample exploit that
# interfaces with a tcp socket
from netcat import Netcat
# start a new Netcat() instance
nc = Netcat('127.0.0.1', 53121)
# get to the prompt
nc.read_until('>')
# start a new note
nc.write('new' + '\n')
nc.read_until('>')
# set note 0 with the payload
nc.write('set' + '\n')
nc.read_until('id:')
@Dangle76
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Dangle76 commented Jan 6, 2017

This may be a dumb question, however I'm a bit of a novice with python in general. If I connect to say, port 21 on a windows machine with this and it spits out the "Microsoft FTP" banner, how would I capture that response since it doesn't seem to output on stdout?

@ewan115
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ewan115 commented Mar 7, 2017

Does it work with Netcat windows version?

@thobiasn
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thobiasn commented Sep 10, 2017

@Dangle76 I am looking for this answer as well. Will respond if I get it working.

Easier than I thought
Turns out you can simply call:

output = nc.read()
print output

Which will save the current output to a variable and print it.

@yuvalyo
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yuvalyo commented May 24, 2018

hi
im getting this error
Traceback (most recent call last):
File "C:\Users\magshimim\Desktop\pingPong.py", line 62, in
main()
File "C:\Users\magshimim\Desktop\pingPong.py", line 46, in main
output = nc.read_until(":")
File "C:\Users\magshimim\Desktop\pingPong.py", line 24, in read_until
self.buff += self.socket.recv(1024)
TypeError: must be str, not bytes

can you tell what it means?

@kolayne
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kolayne commented Sep 13, 2018

hi
im getting this error
Traceback (most recent call last):
File "C:\Users\magshimim\Desktop\pingPong.py", line 62, in
main()
File "C:\Users\magshimim\Desktop\pingPong.py", line 46, in main
output = nc.read_until(":")
File "C:\Users\magshimim\Desktop\pingPong.py", line 24, in read_until
self.buff += self.socket.recv(1024)
TypeError: must be str, not bytes

can you tell what it means?

Replace line 9 with self.buff = b''
And use output = nc.read_until(b":") instead of output = nc.read_until(":") in your code

@NightFalcon650
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NightFalcon650 commented Dec 27, 2021

With the above scripts is it also possible to receive the data, after this send a reaction en receive the next message and so on and on?
How could I realise this and does some one have a example script for this?

@Tugamer89
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Tugamer89 commented Mar 13, 2022

why sometimes does it take a long time to read the response?

@brenw0rth
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brenw0rth commented Apr 1, 2022

Hi, just in case anyone here is interested, I've recently made a Netcat library for Python.
Here is the GitHub repo for the project if you want to check it out.

Please note that it is still in early development and if anyone has any feedback or suggestions please let me know.
Thank you 😊

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