pk_conn

#!/usr/bin/python -u
#
# This is a minimal netcat replacement for connecting to "virtual" raw TCP
# services behind PageKite's HTTP proxy.
#
# For the search engines: This file demonstrates non-blocking IO in Python,
# using stdin, stdout, a socket and select.
#
# This file is in the Public Domain.
#
import os, fcntl, socket, sys, select

def unblock(f):
  fd = f.fileno()
  fl = fcntl.fcntl(fd, fcntl.F_GETFL)
  fcntl.fcntl(fd, fcntl.F_SETFL, fl | os.O_NONBLOCK)

def netcat(s, i, o):
  unblock(s)
  unblock(i)
  while True:
    in_r, out_r, err_r = select.select([s, i], [s, o], [s, i, o], 10)
    if s in in_r:
      data = s.recv(4096)
      if data == "": break
      o.write(data)
    if i in in_r:
      data = os.read(i.fileno(), 4096)
      if data == "":
        s.shutdown(socket.SHUT_WR)
      else:
        s.sendall(data)
  s.close()

def http_connect_netcat(hostname, port, proxy_host, proxy_port):
  s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
  s.connect((proxy_host, proxy_port))
  s.sendall('CONNECT %s:%s HTTP/1.0\r\n\r\n' % (hostname, port))
  reply = s.recv(4096)
  if reply.startswith('HTTP/1.0 200'):
    netcat(s, sys.stdin, sys.stdout) 
    return True
  else:
    sys.stderr.write(reply)
    sys.stderr.write('\n')
    return False

try:
  dest_host = sys.argv[1]
  dest_port = int(sys.argv[2])
  proxy_host = (len(sys.argv) >= 4) and sys.argv[3] or dest_host
  proxy_port = (len(sys.argv) == 5) and int(sys.argv[4]) or 443
except:
  sys.stderr.write(('Usage: %s <dest-host> <dest-port> '
                    '[<proxy-host> [<proxy-port>]]\n') % sys.argv[0])
  sys.exit(1)

if not http_connect_netcat(dest_host, dest_port, proxy_host, proxy_port):
  sys.exit(2)