'''
Created on Feb 28, 2017
@author: Wyko
'''
from netmiko import NetMikoAuthenticationException
from netmiko import NetMikoTimeoutException
from netcrawl import config
from netcrawl.util import port_is_open
from netcrawl.wylog import log, logging
[docs]def connect(handler=None,
netmiko_platform=None,
ip=None,
cred=None,
port=None):
"""
Starts a CLI session with a remote device.
Uses Netmiko to start a SSH or Telnet session with a target device. It will attempt
to use SSH first, and if it fails it will try Telnet. For each connection method, it
will attempt each credential specified in the cred argument (if specified) or the
config.cc.credentials list otherwise.
Keyword Args:
cred (dict): If supplied, this method will only use the specified credential.
Uses the config.cc.credentials list otherwise.
port (int): If supplied, this method will connect only on this port
ip (str): The IP address to connect to
netmiko_platform (str): The platform of the device, in the Netmiko format
handler (ConnectHandler): A Netmiko-type handler to use. Currently using
one of Netmiko.ConnectHandler, Netmiko.ssh_autodetect.SSHDetect.
Uses Netmiko.ConnectHandler by default.
Returns:
dict: A dict containing:
- **connection** (*ConnectHandler*): A Netmiko ConnectHandler object with a successfully opened connection
- **tcp_22** (*bool*): True if port 22 is open
- **tcp_23** (*bool*): True if port 23 is open
- **username** (*str*): The first successful credential's username
- **password** (*str*): The first successful credential's password
- **cred_type** (*str*): The first successful credential's type
Raises:
IOError: If a connection could not be established
AssertionError: If error checking failed
"""
proc = 'cli.connect'
log('Connecting to %s device %s' % (netmiko_platform, ip), ip=ip, proc=proc, v=logging.I)
assert isinstance(ip, str), proc + ': Ip [{}] is not a string.'.format(type(ip))
result = {
'tcp_22': port_is_open(22, ip),
'tcp_23': port_is_open(23, ip),
'connection': None,
'username': None,
'password': None,
'cred_type': None,
}
# Error checking
if cred: # User supplied credentials
assert isinstance(cred, dict), 'Cred is type [{}]. Should be dict.'.format(type(cred))
else:
assert len(config.cc.credentials) > 0, 'No credentials available'
if port: assert port is 22 or port is 23, 'Invalid port number [{}]. Should be 22 or 23.'.format(str(port))
# Switch between global creds or argument creds
if cred: _credList = cred
else: _credList = config.cc.credentials
# Check to see if SSH (port 22) is open
if not result['tcp_22']:
log('Port 22 is closed on %s' % ip, ip=ip, proc=proc, v=logging.I)
elif port is None or port is 22:
# Try wylog in with each credential we have
for cred in _credList:
try:
# Establish a connection to the device
result['connection'] = handler(
device_type=netmiko_platform,
ip=ip,
username=cred['username'],
password=cred['password'],
secret=cred['password'],
)
result['username'] = cred['username']
result['password'] = cred['password']
result['cred_type'] = cred['cred_type']
log('Successful ssh auth to %s using %s, %s' % (ip, cred['username'], cred['password'][:2]), ip=ip, proc=proc, v=logging.N)
return result
except NetMikoAuthenticationException:
log ('SSH auth error to %s using %s, %s' % (ip, cred['username'], cred['password'][:2]), ip=ip, proc=proc, v=logging.A)
continue
except NetMikoTimeoutException:
log('SSH to %s timed out.' % ip, ip=ip, proc=proc, v=logging.A)
# If the device is unavailable, don't try any other credentials
break
except Exception as e:
log('SSH to [{}] failed due to [{}] error: [{}]'.format(ip, type(e).__name__, str(e)))
break
# Check to see if port 23 (telnet) is open
if not result['tcp_23']:
log('Port 23 is closed on %s' % ip, ip=ip, proc=proc, v=logging.I)
elif port is None or port is 23:
for cred in _credList:
try:
# Establish a connection to the device
result['connection'] = handler(
device_type=netmiko_platform + '_telnet',
ip=ip,
username=cred['username'],
password=cred['password'],
secret=cred['password'],
)
result['username'] = cred['username']
result['password'] = cred['password']
result['cred_type'] = cred['cred_type']
log('Successful ssh auth to %s using %s, %s' % (ip, cred['username'], cred['password'][:2]), ip=ip, proc=proc, v=logging.N)
return result
except NetMikoAuthenticationException:
log('Telnet auth error to %s using %s, %s' %
(ip, cred['username'], cred['password'][:2]), ip=ip, v=logging.A, proc=proc)
continue
except NetMikoTimeoutException:
log('Telnet to %s timed out.' % ip, ip=ip, proc=proc, v=logging.A)
# If the device is unavailable, don't try any other credentials
break
except Exception as e:
log('Telnet to [{}] failed due to [{}] error: [{}]'.format(ip, type(e).__name__, str(e)),
ip=ip, proc=proc, v=logging.A)
break
raise IOError(proc + ': CLI connection to [{}] failed'.format(ip))