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#!/usr/bin/env python
import socket
import sys
import time
# action can be reflect or drop
action = "drop"
def handle_connection (connection, client_address):
print("Received connection from {}".format(repr(client_address)))
try:
while True:
data = connection.recv(4096)
if not data:
break;
if (action != "drop"):
connection.sendall(data)
finally:
connection.close()
def run_server(ip, port):
print("Starting server {}:{}".format(repr(ip), repr(port)))
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
server_address = (ip, int(port))
sock.bind(server_address)
sock.listen(1)
while True:
connection, client_address = sock.accept()
handle_connection (connection, client_address)
def prepare_data():
buf = []
for i in range (0, pow(2, 16)):
buf.append(i & 0xff)
return bytearray(buf)
def run_client(ip, port):
print("Starting client {}:{}".format(repr(ip), repr(port)))
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server_address = (ip, port)
sock.connect(server_address)
data = prepare_data()
n_rcvd = 0
n_sent = len (data)
try:
sock.sendall(data)
timeout = time.time() + 2
while n_rcvd < n_sent and time.time() < timeout:
tmp = sock.recv(1500)
tmp = bytearray (tmp)
n_read = len(tmp)
for i in range(n_read):
if (data[n_rcvd + i] != tmp[i]):
print("Difference at byte {}. Sent {} got {}"
.format(n_rcvd + i, data[n_rcvd + i], tmp[i]))
n_rcvd += n_read
if (n_rcvd < n_sent or n_rcvd > n_sent):
print("Sent {} and got back {}".format(n_sent, n_rcvd))
else:
print("Got back what we've sent!!");
finally:
sock.close()
def run(mode, ip, port):
if (mode == "server"):
run_server (ip, port)
elif (mode == "client"):
run_client (ip, port)
else:
raise Exception("Unknown mode. Only client and server supported")
if __name__ == "__main__":
if (len(sys.argv)) < 4:
raise Exception("Usage: ./dummy_app <mode> <ip> <port> [<action>]")
if (len(sys.argv) == 5):
action = sys.argv[4]
run (sys.argv[1], sys.argv[2], int(sys.argv[3]))
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