This code is for sending and receiving between my PC and AWS Instance
I want to know whether the transmitted data is considered secure? or do I need something else to ensure the security of the transmitted data?
If the data is not encrypted, what is the addition to the code to make it secure?
code's client
import socket
HOST = "public ip of server"
PORT = 4444 # The port used by the server
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
s.connect((HOST, PORT))
s.sendall(b"Hello, world")
data = s.recv(1024)
print(f"Received {data!r}")
server's code
server code
import socket
HOST = "0.0.0.0"
PORT = 4444 #open this in your router
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
s.bind((HOST, PORT))
s.listen()
conn, addr = s.accept()
with conn:
print(f"Connected by {addr}")
while True:
data = conn.recv(1024)
if not data:
break
conn.sendall(data)
Related
trying to ping a server from a client like this:
#server
import socket
HOST = ''
PORT = 50007
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((HOST, PORT))
s.listen(1)
conn, addr = s.accept()
print ('Connected by', addr)
while 1:
data = conn.recv(1024)
if not data: break
conn.sendall(data)
conn.close()
#client
import socket
HOST = ''
PORT = 50007
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
s.connect((HOST, PORT))
s.sendall(b"Hello, world")
data = s.recv(1024)
print(f"Received {data!r}")
But there is a hang on server side after the s.accept(), and ...[111] connection refused on the client side.
BTW: I am on a windows machine for the server, and pinging from a linux machine. They are connected with an ethernet cable. I have also set a static address for the linux machine, from the windows machine.
Another thing, is that the exact same code works in the opposite direction ...
Could someone help?! Stuck on this for ages!
I am trying to connect a server to a client in python with sockets.
The problem is that with ipv6 binding, it works on my local network. What I want is to connect it to another network. These programs are written in Python 3
Here is the code of server.py:
import socket
HOST = someip
PORT = someport
server = socket.socket(socket.AF_INET6, socket.SOCK_STREAM)
server.bind((HOST, PORT))
server.listen()
Source code of client.py:
import socket
HOST = someip
PORT = someport
client = socket.socket(socket.AF_INET6, socket.SOCK_STREAM)
client.connect((HOST, PORT))
I think it is a port forwarding problem.
I know the code does nothing right now, but I want to first establish the connection.
When the server receives a request, we need to put it in a loop to accept it.
Like this
import socket
HOST = someip
PORT = someport
server = socket.socket(socket.AF_INET6, socket.SOCK_STREAM)
server.bind((HOST, PORT))
server.listen()
while True:
try:
conn, addr = server.accept()
print(f"New request from {addr}")
except KeyboardInterrupt:
server.close()
I make client-sever app. It look like this:
client
import socket
host = '127.0.0.1'
port = 1338
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((host, port))
while True:
st = input("Your message: ")
byt = st.encode()
s.send(byt)
server
import socket
host = ''
port = 1338
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((host, port))
while True:
s.listen(5)
conn, addr = s.accept()
data = conn.recv(2000)
print(data.decode())
Problem is that only first message is display. How can I solve this problem?
The server receives data only once after accepting a connection from the client. In-order to receive continuously, you can have a while loop for receiving data from the client.
import socket
host = ''
port = 1338
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((host, port))
while True:
s.listen(5)
conn, addr = s.accept()
condition = True
while condition:
data = conn.recv(2000)
if not data: break
print(data.decode())
So, the above code will receive data as long the user provides data. You can separate the data receiving part in a separate thread too.
As you have the client's connect outside the loop, you have to place the server's listen and accept also outside the loop, since the connection is to be established only once.
Note : This problem has been completely solved, as was am running client.py before server.py
Just got started with socket programming, I have created the below code and expecting to print some byte message, but it isn't doing that.
I just want to make the message available for any person on any
machine. But it's refusing by the machine to do that.
Here is my code:
server.py
import socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
port = 12048
s.bind((socket.gethostname(), port))
s.listen()
while True:
c, addr = s.accept()
print("Got connection from", addr)
c.send(bytes("Thank you", "utf-8"))
client.py
import socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
port = 12048
s.connect(('192.168.0.1', port))
msg = s.recv(1024)
print(msg.decode("utf-8"))
Some images to better explain my errors:
Any help would be appreciated!!!
It looks like in the server.py script you use s.bind((socket.gethostname(), port)) where socket.gethostname() is a hostname, but in the client.py script you use s.connect(('192.168.0.1', port)) where '192.168.0.1' is the hostname you are trying to connect.
I think there you have socket.gethostname() != '192.168.0.1' and that's the problem.
Also, you can bind to all available IP addresses on the host using this solution Python socket bind to any IP?
Let's use listen_ip = socket.gethostbyname(socket.gethostname()) for connection since socket.gethostname() may return hostname instead of IP and it will not be solved by python dns resolver in local network if it was local name, not DNS.
and use it later as s.bind((listen_ip, port)) and s.connect((listen_ip, port))
After some debugging I've got a working solution for you
There are the scripts required.
server.py
import socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
host = socket.gethostbyname(socket.gethostname())
port = 12_048
s.bind((host, port))
s.listen()
print("Server listening # {}:{}".format(host, port))
while True:
c, addr = s.accept()
print("Got connection from", addr)
c.send(bytes("Thank you", "utf-8"))
client.py
import socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
host = '192.168.1.162' # The IP printed by the server must be set here
# or we can set it using env variable named SERVER_IP
if 'SERVER_IP' in os.environ:
host = os.environ['SERVER_IP']
port = 12048
print("Connecting to {}:{}".format(host, port))
s.connect((host, port))
msg = s.recv(1024)
print(msg.decode("utf-8"))
In a chat conversation we concluded that the hardcoded IP in the question is not the correct one. This solution does have the IP he needed but it will be different in each case. Remeber that server.py needs to be launched first, and when you see the printed Server listening # IP:12048, write that IP in client.py and launch it. Client does need to be launched after seeing that line even if you already know the IP, as the server needs some time to be ready and the client will crash if it tries to connect to the server while it is not ready.
server.py
import socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
host = socket.gethostbyname(socket.gethostname())
port = 12048
s.bind((host, port))
s.listen()
print("Server listening # {}:{}".format(host, port))
while True:
c, addr = s.accept()
print("Got connection from", addr)
c.send(bytes("Thank you", "utf-8"))
client.py
import socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
host = '192.168.1.162' # The IP printed by the server must be set here
port = 12048
print("Connecting to {}:{}".format(host, port))
s.connect((host, port))
msg = s.recv(1024)
print(msg.decode("utf-8"))
A simple demo of socket programming in python:
server.py
import socket
host = '127.0.0.1'
port = 8000
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((host, port))
s.listen(1)
conn, addr = s.accept()
while True:
data = conn.recv(1024)
print 'Received:', data
if not data:
break
conn.sendall(data)
print 'Sent:', data
conn.close()
client.py
import socket
host = '127.0.0.1'
port = 8000
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((host, port))
s.sendall('Hel')
s.sendall('lo world!')
print 'Received:', s.recv(1024)
s.close()
Now code work well. However, the client may not know if server will always send back every time. I tried symmetric code of while-loop in server.py
client_2.py
import socket
host = '127.0.0.1'
port = 8000
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((host, port))
s.sendall('Hel')
s.sendall('lo world!')
while True:
data = s.recv(1024)
if not data:
break
print 'Received:', data
s.close()
This code will block at
data = s.recv(1024)
But in server.py, if no data received, it will be blank string, and break from while-loop
Why it does not work for client? How can I do for same functionality without using timeout?
You can set a socket to non-blocking operation via socket.setblocking(false), which is equivalent to socket.settimeout(0). Solving this "without using timeout" is impossible.