socket 编程 例子代码中s.recv 如果接受不到数据，会阻塞，需要对这块代码进行优化，否则循环不会结束。
import socket
ports = [21, 22, 53, 445, 80, 443, 3389, 8080]
hosts = ['127.0.0.1', '10.10.10.10', '192.168.1.1']
for host in hosts:
for port in ports:
try:
s = socket.socket()
print "[+] Attempting to connect to " + host + ":" + str(port)
s.connect((host, port))
s.send('absdkfbsdafblabldsfdbfhasdflbf /n')
banner = s.recv(1024)
if banner:
print "[+] " + host + ":" + str(port) + " open: \n" + banner
s.close()
except:
pass反向shell
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