Python Tutorial - SSH password authentication¶

This tutorial describes the how you can use generated UTIM session key to connect to server via ssh

Uhost¶

Run Uhost as described in Python Tutorial - Hello World.

Creating users¶

Code of this example here.

This script creates new user for linux machine using UTIM ID’s as username and UTIM’s session key as password

Step:

Connect to database
Select IDs and keys of UTIMs
Create or delete (if exists) and create new user.

UTIM¶

Code of this example here.

Steps:

Import from UTIM library

from utim.connectivity.manager import ConnectivityConnectError
from utim.utim import Utim
from utim.connectivity import DataLinkManager, TopDataType
from utim.connectivity.manager import ConnectivityManager
from utim.utilities.tag import Tag
from utim.utilities.exceptions import UtimConnectionException, UtimInitializationError

Initialize two queues - first is for receiving and second is for transmitting
```
rx_queue = queue.Queue()
tx_queue = queue.Queue()
```
Initialize ConnectivityManager - utility to read data from queues. To use queues to send and receive data you should set argument dl_type=DataLinkManager.TYPE_QUEUE to ConnectifityManager
```
cm1 = ConnectivityManager()
cm1.connect(dl_type=DataLinkManager.TYPE_QUEUE, rx=tx_queue, tx=rx_queue)
```

Create UTIM object and run it

concrete_utim = Utim()
concrete_utim.connect(dl_type=DataLinkManager.TYPE_QUEUE, rx=rx_queue, tx=tx_queue)
concrete_utim.run()

Send data to start communication:

data1 = [TopDataType.DEVICE, Tag.INBOUND.NETWORK_READY]
cm1.send(data1)

Wait for session key and stop it when the key is received

while True:
    data = cm1.receive()
    if data:
        session_key = data[1]
        concrete_utim.stop()
        break

Use paramiko library to connect via ssh, execute command and print result of command executing:

ssh = paramiko.SSHClient()
ssh.load_system_host_keys()
ssh.connect(_SERVER, username=_UTIM_NAME.hex().upper(), password=session_key.hex())
ssh_stdin, ssh_stdout, ssh_stderr = ssh.exec_command('ifconfig')
for line in iter(ssh_stdout.readline, ""):
    print(line, end="")
ssh.close()

Finally, stop Utim (if not stopped) and ConnectivityManager before exit
```
concrete_utim.stop()

cm1.stop()
```