import sys,re,time
import pexpect
import exceptions
from string import *
from telnetlib import Telnet
""" Define exceptions """
class TelnetError(exceptions.Exception):
def __init__(self, args=None):
self.args=args
self.errmsg = ''
for a in self.args:
self.errmsg += str(a)
class JumpError(exceptions.Exception):
def __init__(self, args=None):
self.args=args
self.errmsg = ''
for a in self.args:
self.errmsg += str(a)
class Jump:
""" Initiate an SSH tunnel
"""
def __init__(self, host, env = {}):
""" If env not passed explicitly, then
assume that its inherited from parent
class.
"""
if env != {}:
self.env = env
self._jump_params()
sshcmd = "ssh %s -L %s:%s:23" % \
(self.jumpserver,self.jumpport,host)
if self.DEBUG >= 3: print "ssh cmd: %s" % (sshcmd)
""" Create SSH tunnel """
self.tunnel = pexpect.spawn(sshcmd)
if self.DEBUG >= 2: print "jump to %s:%s" % \
(self.jumpserver,self.jumpport)
if self.DEBUG >= 3: print "waiting for %s" % \
(self.jumpprompt)
""" Process response from jump server """
expected_replies = [self.jumpprompt,\
'Are you sure you want to continue connecting'\
'ssword:']
while 1:
response = self.tunnel.expect(expected_replies)
if response == 0: # got prompt
break
""" Got ssh password, prompt, so no public
key encryption set up
"""
if response == 1:
if self.env.has_key('SSHPASSWD'):
self.sshpassword = "%s\n" % \
(self.env['SSHPASSWD'])
else:
raise JumpError, "no SSH Password"
self._ssh_login()
""" If prompted, add to known_hosts file """
if response == 2:
self.tunnel.send("yes\n")
if self.DEBUG >= 1: print self.tunnel.before
if self.DEBUG >= 3: print "tunnel %s:%s established" % \
(self.jumpserver,self.jumpport)
""" Process parameters needed to create the
SSH tunnel to the Jump host
"""
def _jump_params(self):
""" Set debug level """
if self.env.has_key('DEBUG'):
self.DEBUG = int(self.env['DEBUG'])
else:
self.DEBUG = 0
try:
self.jumpserver = self.env['JMPSERVER']
self.jumpport = self.env['PORT']
self.jumpprompt = self.env['JMPPROMPT']
except:
raise JumpError, "missing parameters"
return 0
""" Login with SSH password
"""
def _ssh_login(self):
if self.DEBUG >= 1: print self.tunnel.before
self.tunnel.send(self.sshpassword)
class Climgmt(Jump):
def __init__(self,host,env = {}):
self.host = host
""" If no environment passed as a parameter,
then assume environment is inherited from
parent class.
"""
if env != {}:
self.env = env
self._climgmt_params()
""" Create ssh tunnel is jump server specified """
if self.jumpserver != None:
Jump.__init__(self,host)
if self.DEBUG >= 3: print "Telneting to %s on port %d" % \
(self.host, self.port)
""" Initiate Telnet session """
try:
self.session = Telnet(self.host, self.port)
except:
self.tunnel.close()
raise TelnetError, "cannot establish telnet session"
""" Set parameters
"""
def _climgmt_params(self):
""" Debug level """
if self.env.has_key('DEBUG'):
self.DEBUG = int(self.env['DEBUG'])
else:
self.DEBUG = 0
""" Device prompt """
if self.env.has_key('PROMPT'):
self.prompt = self.env['PROMPT']
else:
self.prommpt = None
""" Jump server """
if self.env.has_key('JMPSERVER'):
self.jumpserver = self.env['JMPSERVER']
self.host = "localhost"
else:
self.jumpserver = None
""" The Telnet port maybe different because we are
going through a jump server (ssh tunnel).
"""
if self.env.has_key('PORT'):
self.port = int(self.env['PORT'])
else:
self.port = 23 # default Telnet port
return 0
""" Issue a command to the Telnet device
"""
def cmd(self, cmd, newprompt = None):
if newprompt == None:
prompt = self.prompt
else:
prompt = newprompt
self.session.write(cmd+'\n')
response = self.session.read_until(prompt,8)
if self.DEBUG >= 3: print response
lines = response.split('\n')
lines = map(lambda i: strip(strip(i,'\r')), lines)
return lines
""" Close telnet session (and ssh tunnel)
"""
def close(self):
if self.DEBUG >= 3: print "closing Telnet session <%s,%d>" % \
(self.host, self.port)
""" Close Telnet session """
self.session.close() # close telnet session
""" Check to see if tunnel exists (note: must
find better way of check if tunnel exists)
"""
try:
tunnel_exists = self.tunnel
except AttributeError, e:
return -1
except NameError, e:
return -1
if self.DEBUG >= 3: print "closing ssh tunnel <%s,%s>" % \
(self.jumpserver, self.jumpport)
""" Close ssh tunnel (if it exists) """
self.tunnel.close() # close tunnel
