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#!/usr/bin/python
import sys, os, socket, threading, getpass, logging, time, base64, select, termios, tty, traceback
import secsh
##### utility functions
def load_host_keys():
filename = os.environ['HOME'] + '/.ssh/known_hosts'
keys = {}
try:
f = open(filename, 'r')
except Exception, e:
print '*** Unable to open host keys file (%s)' % filename
return
for line in f:
keylist = line.split(' ')
if len(keylist) != 3:
continue
hostlist, keytype, key = keylist
hosts = hostlist.split(',')
for host in hosts:
if not keys.has_key(host):
keys[host] = {}
keys[host][keytype] = base64.decodestring(key)
f.close()
return keys
##### main demo
# setup logging
l = logging.getLogger("secsh")
l.setLevel(logging.DEBUG)
if len(l.handlers) == 0:
f = open('demo.log', 'w')
lh = logging.StreamHandler(f)
lh.setFormatter(logging.Formatter('%(levelname)-.3s [%(asctime)s] %(name)s: %(message)s', '%Y%m%d:%H%M%S'))
l.addHandler(lh)
username = ''
if len(sys.argv) > 1:
hostname = sys.argv[1]
if hostname.find('@') >= 0:
username, hostname = hostname.split('@')
else:
hostname = raw_input('Hostname: ')
if len(hostname) == 0:
print '*** Hostname required.'
sys.exit(1)
port = 22
if hostname.find(':') >= 0:
hostname, portstr = hostname.split(':')
port = int(portstr)
# now connect
try:
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect((hostname, port))
except Exception, e:
print '*** Connect failed: ' + str(e)
traceback.print_exc()
sys.exit(1)
try:
event = threading.Event()
t = secsh.Transport(sock)
t.ultra_debug = 0
t.start_client(event)
# print repr(t)
event.wait(10)
if not t.is_active():
print '*** SSH negotiation failed.'
sys.exit(1)
# print repr(t)
keys = load_host_keys()
keytype, hostkey = t.get_remote_server_key()
if not keys.has_key(hostname):
print '*** WARNING: Unknown host key!'
elif not keys[hostname].has_key(keytype):
print '*** WARNING: Unknown host key!'
elif keys[hostname][keytype] != hostkey:
print '*** WARNING: Host key has changed!!!'
sys.exit(1)
else:
print '*** Host key OK.'
event.clear()
# get username
if username == '':
default_username = getpass.getuser()
username = raw_input('Username [%s]: ' % default_username)
if len(username) == 0:
username = default_username
# ask for what kind of authentication to try
default_auth = 'p'
auth = raw_input('Auth by (p)assword, (r)sa key, or (d)ss key? [%s] ' % default_auth)
if len(auth) == 0:
auth = default_auth
if auth == 'r':
key = secsh.RSAKey()
default_path = os.environ['HOME'] + '/.ssh/id_rsa'
path = raw_input('RSA key [%s]: ' % default_path)
if len(path) == 0:
path = default_path
key.read_private_key_file(path)
t.auth_key(username, key, event)
elif auth == 'd':
key = secsh.DSSKey()
default_path = os.environ['HOME'] + '/.ssh/id_dsa'
path = raw_input('DSS key [%s]: ' % default_path)
if len(path) == 0:
path = default_path
key.read_private_key_file(path)
t.auth_key(username, key, event)
else:
pw = getpass.getpass('Password for %s@%s: ' % (username, hostname))
t.auth_password(username, pw, event)
event.wait(10)
# print repr(t)
if not t.is_authenticated():
print '*** Authentication failed. :('
t.close()
sys.exit(1)
chan = t.open_session()
chan.get_pty()
chan.invoke_shell()
print '*** Here we go!'
print
try:
oldtty = termios.tcgetattr(sys.stdin)
tty.setraw(sys.stdin.fileno())
tty.setcbreak(sys.stdin.fileno())
chan.settimeout(0.0)
while 1:
r, w, e = select.select([chan, sys.stdin], [], [])
if chan in r:
try:
x = chan.recv(1024)
if len(x) == 0:
print
print '*** EOF\r\n',
break
sys.stdout.write(x)
sys.stdout.flush()
except socket.timeout:
pass
if sys.stdin in r:
# FIXME: reading 1 byte at a time is incredibly dumb.
x = sys.stdin.read(1)
if len(x) == 0:
print
print '*** Bye.\r\n',
break
chan.send(x)
finally:
termios.tcsetattr(sys.stdin, termios.TCSADRAIN, oldtty)
chan.close()
t.close()
except Exception, e:
print '*** Caught exception: ' + str(e.__class__) + ': ' + str(e)
traceback.print_exc()
try:
t.close()
except:
pass
sys.exit(1)
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