| #!/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])) |