python获取交互式ssh shell的方法

#coding=utf8
 
'''
用python实现了一个简单的shell，了解进程创建
类unix 环境下 fork和exec 两个系统调用完成进程的创建
'''
 
import sys, os
 
 
def myspawn(cmdline):
 argv = cmdline.split()
 if len(argv) == 0:
  return 
 program_file = argv[0]
 pid = os.fork()
 if pid < 0:
  sys.stderr.write("fork error")
 elif pid == 0:
  # child
  os.execvp(program_file, argv)
  sys.stderr.write("cannot exec: "+ cmdline)
  sys.exit(127)
 # parent
 pid, status = os.waitpid(pid, 0)
 ret = status >> 8 # 返回值是一个16位的二进制数字，高8位为退出状态码，低8位为程序结束系统信号的编号
 signal_num = status & 0x0F
 sys.stdout.write("ret: %s, signal: %s\n" % (ret, signal_num))
 return ret
 
 
def ssh(host, user, port=22, password=None):
 if password:
  sys.stdout.write("password is: '%s' , plz paste it into ssh\n" % (password))
 cmdline = "ssh %s@%s -p %s " % (user, host, port)
 ret = myspawn(cmdline)
 
 
if __name__ == "__main__":
 host = ''
 user = ''
 password = ''
 ssh(host, user, password=password)

#coding=utf-8
import socket
import sys
import os
import termios
import tty
import fcntl
import signal
import struct
import select
 
now_channel = None
 
def interactive_shell(chan):
 posix_shell(chan)
 
 
def ioctl_GWINSZ(fd):
 try:
  cr = struct.unpack('hh', fcntl.ioctl(fd, termios.TIOCGWINSZ,'aaaa'))
 except:
  return
 return cr
 
 
def getTerminalSize():
 cr = ioctl_GWINSZ(0) or ioctl_GWINSZ(1) or ioctl_GWINSZ(2)
 return int(cr[1]), int(cr[0])
 
 
def resize_pty(signum=0, frame=0):
 width, height = getTerminalSize()
 if now_channel is not None:
  now_channel.resize_pty(width=width, height=height)
 
 
 
def posix_shell(chan):
 global now_channel
 now_channel = chan
 resize_pty()
 signal.signal(signal.SIGWINCH, resize_pty) # 终端大小改变时，修改pty终端大小
 stdin = os.fdopen(sys.stdin.fileno(), 'r', 0) # stdin buff置为空，否则粘贴多字节或者按方向键的时候显示不正确
 fd = stdin.fileno()
 oldtty = termios.tcgetattr(fd)
 newtty = termios.tcgetattr(fd)
 newtty[3] = newtty[3] | termios.ICANON
 try:
  termios.tcsetattr(fd, termios.TCSANOW, newtty)
  tty.setraw(fd)
  tty.setcbreak(fd)
  chan.settimeout(0.0)
  while True:
   try:
    r, w, e = select.select([chan, stdin], [], [])
   except:
    # 解决SIGWINCH信号将休眠的select系统调用唤醒引发的系统中断，忽略中断重新调用解决。
    continue
   if chan in r:
    try:
     x = chan.recv(1024)
     if len(x) == 0:
      print 'rn*** EOFrn',
      break
     sys.stdout.write(x)
     sys.stdout.flush()
    except socket.timeout:
     pass
   if stdin in r:
    x = stdin.read(1)
    if len(x) == 0:
     break
    chan.send(x)
 finally:
  termios.tcsetattr(sys.stdin, termios.TCSADRAIN, oldtty)

#coding=utf8
import paramiko
import interactive
 
 
#记录日志
paramiko.util.log_to_file('/tmp/aaa')
#建立ssh连接
ssh=paramiko.SSHClient()
ssh.load_system_host_keys()
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
ssh.connect('192.168.1.11',port=22,username='hahaha',password='********',compress=True)
 
#建立交互式shell连接
channel=ssh.invoke_shell()
#建立交互式管道
interactive.interactive_shell(channel)
#关闭连接
channel.close()
ssh.close()