text: # -*- coding: latin-1 -*-
  #
  # Copyright (C) AB Strakt
  # Copyright (C) Jean-Paul Calderone
  # See LICENSE for details.
  
  """
  Simple SSL client, using blocking I/O
  """
  
  import os
  import socket
  import sys
  
  from OpenSSL import SSL, crypto
  
  
  def verify_cb(conn, cert, errnum, depth, ok):
      certsubject = crypto.X509Name(cert.get_subject())
      commonname = certsubject.commonName
      print('Got certificate: ' + commonname)
      return ok
  
  
  if len(sys.argv) < 3:
      print('Usage: python client.py HOST PORT')
      sys.exit(1)
  
  
  dir = os.path.dirname(sys.argv[0])
  if dir == '':
      dir = os.curdir
  
  
  # Initialize context
  ctx = SSL.Context(SSL.SSLv23_METHOD)
  ctx.set_options(SSL.OP_NO_SSLv2)
  ctx.set_options(SSL.OP_NO_SSLv3)
  ctx.set_verify(SSL.VERIFY_PEER, verify_cb)  # Demand a certificate
  ctx.use_privatekey_file(os.path.join(dir, 'client.pkey'))
  ctx.use_certificate_file(os.path.join(dir, 'client.cert'))
  ctx.load_verify_locations(os.path.join(dir, 'CA.cert'))
  
  # Set up client
  sock = SSL.Connection(ctx, socket.socket(socket.AF_INET, socket.SOCK_STREAM))
  sock.connect((sys.argv[1], int(sys.argv[2])))
  
  while 1:
      line = sys.stdin.readline()
      if line == '':
          break
      try:
          sock.send(line)
          sys.stdout.write(sock.recv(1024).decode('utf-8'))
          sys.stdout.flush()
      except SSL.Error:
          print('Connection died unexpectedly')
          break
  
  
  sock.shutdown()
  sock.close()
  