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What is remote port forwarding command `ssh -R 80:localhost:8080 nokey#localhost.run` equivalent to in Paramiko?

ssh -R 80:localhost:8080 nokey#localhost.run is equivalent to what in Paramiko?
I search a lot but no success ...
Code I tried
import paramiko
command = "df"
# Update the next three lines with your
# server's information
username = "localhost:9876"
host = "nokey#localhost.run"
client = paramiko.client.SSHClient()
client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
client.connect(host,port=80, username=username)
_stdin, _stdout,_stderr = client.exec_command("df")
print(stdout.read().decode())
client.close()

A partial equivalent is Transport.request_port_forward.
But that will only setup the server-side part of the forwarding. The local-side implementation that will establish the local connection from the SSH client (Paramiko) to the local server is up to you.
An example how to implement it is given in demos/rforward.py.
An equivalent of your command will be:
python3 rforward.py -u nokey -p 80 -r 127.0.0.1:8080 localhost.run
Note that the rforward.py script does not start a shell. It just does the forwarding. So it's actually an equivalent of ssh with -N switch.
If you need both forwarding and shell, you will need to modify the script to additionally do SSHClient.invoke_shell like demos/demo.py do.

SSHLibrary prompts for password

I have a problem with a test suite. I use robot framework and python.I created a function in python which executes a console command in a remote Linux client.
def purge_default_dns(device_ip):
ssh_val = "usr1#" + device_ip
command = "ctool dns | grep -v \"grep\" | awk \'{print $2}\'"
test = check_output(["ssh", ssh_val, "-p", "6022", command])
The check_output() function connects with device_ip and executes command. If I try to connect with a fully qualified domain name (ex. my.domain.io), then I get a prompt for password (which is empty). I press enter and command executes regular. Is there any parameter that passes for example Enter when password prompt comes up?
I tried ssh -e switch , I don't want to change ssh client , I just need a generic solution.
For example using paramiko library in the code below , I can create an paramiko SSHClient , which has a parameter for password and doesn't prompt anything. While I can't use paramiko right now , I need something else with SSHLirary to go around the problem.
def send_ssh_command(device_ip , command):
hostname = device_ip
password = ""
username = "usr1"
port = 6022
try:
client = paramiko.SSHClient()
client.load_system_host_keys()
client.set_missing_host_key_policy(paramiko.WarningPolicy())
client.connect(hostname, port=port, username=username, password=password)
stdin , stdout , stderr = client.exec_command(command)
command_return_val = stdout.read()
finally:
client.close()
return command_return_val
Thank you.

To get this straight, the only solution you look for is to pass the password on the command line to the default OS ssh client, and do not/cannot install any libraries (paramiko, etc) that can help you achieve the same result through other means?
I'm asking this, because the robot framework's SSHLibrary provides this out of the box; you already have the python's solution with paramiko; and the general linux solution is to install the sshpass package, and use it to pass the value:
sshpass -p "YOUR_PASS" ssh -usr1#my.domain.io:6022
So if all of these are not an option, you are left with two alternatives - either hack something around SSH_ASKPASS - here's an article with a sample, or use expect to pass it - this one is what I'd prefer out of the two.
Here's a very good SO answer with an expect script wrapper around ssh. In your method, you will have to first create a file with its content, set an executable flag on it, and then call that file in check_output(), passing as arguments the password, 'ssh' and all its arguments.

Why You need to go with python , I am using below code in robotframework for the same:
[Arguments] ${host}=${APP_SERVER} ${username}=${APP_USERNAME} ${password}=${APP_PASSWORD}
Open Connection ${host} timeout=2m
Login ${username} ${password}
${out} ${err} ${rc}= Execute Command cd ${PATH};ctool dns | grep -v \"grep\" | awk \'{print $2}\' * return_stdout=True return_stderr=True return_rc=True
Should Be Equal ${rc} ${0}

Subprocess on remote server

I am using this code for executing command on remote server.
import subprocess
import sys
COMMAND="ls"
ssh = subprocess.Popen(["ssh", "%s" % HOST, COMMAND],
shell=False,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
result = ssh.stdout.readlines()
if result == []:
error = ssh.stderr.readlines()
print >>sys.stderr, "ERROR: %s" % error
else:
print result
When I try to execute this script, I get prompt for password. Is there any way I could avoid it, for example, can I enter password in script somehow? Also, password should be encrypted somehow so that people who have access to the script cannot see it.

Why make it so complicated? Here's what I suggest:
1) Create a ssh config section in your ~/.ssh/config file:
Host myserver
HostName 50.50.50.12 (fill in with your server's ip)
Port xxxx (optional)
User me (your username for server)
2) If you have generated your ssh keypair do it now (with ssh-keygen). Then upload with:
$ ssh-copy-id myserver
3) Now you can use subprocess with ssh. For example, to capture output, I call:
result = subprocess.check_output(['ssh', 'myserver', 'cat', 'somefile'])
Simple, robust, and the only time a password is needed is when you copy the public key to the server.
BTW, you code will probably work just fine as well using these steps.

One way is to create a public key, put it on the server, and do ssh -i /path/to/pub/key user#host or use paramiko like this:
import paramiko
import getpass
ssh = paramiko.SSHClient()
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
p = getpass.getpass()
ssh.connect('hostname', username='user', password=p)
stdin, stdout, stderr = ssh.exec_command('ls')
print stdout.readlines()
ssh.close()

You should use pexpect or paramiko to connect to remote machine,then spawn a child ,and then run subprocess to achieve what you want.

Here's what I did when encountering this issue before:
Set up your ssh keys for access to the server.
Set up an alias for the server you're accessing. Below I'll call it remote_server.
Put the following two lines at the end of ~/.bash_profile.
eval $(ssh-agent -s)
ssh-add
Now every time you start your shell, you will be prompted for a passphrase. By entering it, you will authenticate your ssh keys and put them 'in hand' at the start of your bash session. For the remainder of your session you will be able to run commands like
ssh remote_server ls
without being prompted for a passphrase. Here ls will run on the remote server and return the results to you. Likewise your python script should run without password prompt interruption if you execute it from the shell.
You'll also be able to ssh to the server just by typing ssh remote_server without having to enter your username or password every time.
The upside to doing it this way is that you should be doing this anyway to avoid password annoyances and remembering funky server names :) Also you don't have to worry about having passwords saved anywhere in your script. The only potential downside is that if you want to share the python script with others, they'll have to do this configuring as well (which they should anyway).

You don't really need something like pexpect to handle this. SSH keys already provide a very good and secure solution to this sort of issue.
The simplest way to get the results you want would probably be to generate an ssh key and place it in the .ssh folder of your device. I believe github has a pretty good guide to doing that, if you look into it. Once you set up the keys correctly on both systems, you won't actually have to add a single line to your code. When you don't specify a password it will automatically use the key to authenticate you.

While subprocess.Popen might work for wrapping ssh access, this is not the preferred way to do so.
I recommend using paramiko.
import paramiko
ssh_client = paramiko.SSHClient()
ssh_client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
ssh_client.connect(server, username=user,password=password)
...
ssh_client.close()
And If you want to simulate a terminal, as if a user was typing:
chan=ssh_client.invoke_shell()
def exec_cmd(cmd):
"""Gets ssh command(s), execute them, and returns the output"""
prompt='bash $' # the command line prompt in the ssh terminal
buff=''
chan.send(str(cmd)+'\n')
while not chan.recv_ready():
time.sleep(1)
while not buff.endswith(prompt):
buff+=ssh_client.chan.recv(1024)
return buff[:len(prompt)]
Example usage: exec_cmd('pwd')
If you don't know the prompt in advance, you can set it with:
chan.send('PS1="python-ssh:"\n')

You could use following.
import subprocess
import sys
COMMAND="ls"
ssh = subprocess.Popen("powershell putty.exe user#HOST -pw "password", stdout=PIPE, stdin=PIPE, stderr=STDOUT)
result = ssh.stdout.readlines()
if result == []:
error = ssh.stderr.readlines()
print >>sys.stderr, "ERROR: %s" % error
else:
print result

How do I start an SSH session locally using Python?

What I mean to ask is, if I am on System "A" (Linux) and I want to ssh into System "B" (Windows): On System "A", I can do ssh admin#xx.xx.xx.xx which will prompt me to a password and when that gets authenticated, I will get to the "$" of System "B" (on System "A").
how do I send username and password together as a single line (since I want to use a script)
How to achieve the scenario that I have above.

I generally do it with Paramiko, its easier
import paramiko
# ssh
print 'enter ssh'
ssh = paramiko.SSHClient()
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy()) # this will automatically add the keys
ssh.connect(machineHostName, username=user, password=password)
# Run your commands
# example 1 : ls command
print 'do a ls command'
stdin, stdout, stderr = ssh.exec_command('ls')
print stdout.readlines()
time.sleep(2)
# example 2 : change ip address
print 'changing ip address'
stdin, stdout, stderr = ssh.exec_command('sed -i -- s/'+oldIp+'/'+newIp+'/g /etc/sysconfig/network-scripts/ifcfg-eth0')
print stdout.readlines()
time.sleep(2)
To install Paramiko, you can download the tar.gz file from here.
Assuming you are really new to python, how to install this :
Download the tar.gz file
Extract the contents to a folder
cd into that extracted folder, from your terminal
execute this python setup.py install
then you can try something like the above example
NOTE : if you get stuck with installation comment here, and I can help you.

Instead of using a passphrase for authentication, you could use ssh keys as described here.
Start your ssh client on System "A" using subprocess.call(['/path/to/ssh', 'admin#xx.xx.xx.xx', 'remote_script.sh'])

How to create a SSH tunnel using Python and Paramiko?

I need to create tunneling to read information from a database. I use Paramiko, but I have not worked with tunneling yet. Please provide an example of a simple code that creates and closes a tunnel.

At work we usually create ssh tunnels forwarding ports. The way we do that is, by using the standard command ssh -L port:addr:port addr with subprocess running in a separate thread.
I found this useful link: https://github.com/paramiko/paramiko/blob/master/demos/forward.py with an example of doing port forwarding with paramiko.

I used sshtunnel for my projects. Example of the forwarding remote local MySQL port to the host local port:
pip install sshtunnel
python -m sshtunnel -U root -P password -L :3306 -R 127.0.0.1:3306 -p 2222 localhost

Even though this does not use paramiko, I believe it's a very clean solution to implement (similar to #dario's answer but without managing the thread in python).
There's this little-mentioned feature in openssh client that allows us to control a ssh process through a unix socket, quoting man ssh:
-M Places the ssh client into “master” mode for connection sharing. Multiple -M options places ssh
into “master” mode with confirmation required before slave connections are accepted. Refer to the
description of ControlMaster in ssh_config(5) for details.
-S ctl_path
Specifies the location of a control socket for connection sharing, or the string “none” to disable
connection sharing. Refer to the description of ControlPath and ControlMaster in ssh_config(5)
for details.
So you can start background process of ssh (with -Nf) and then check (or terminate) it with a another ssh call.
I use this in a project that requires a reverse tunnel to be established
from subprocess import call, STDOUT
import os
DEVNULL = open(os.devnull, 'wb')
CONFIG = dict(
SSH_SERVER='ssh.server.com',
SSH_PORT=2222,
SSH_USER='myuser',
SSH_KEY='/path/to/user.key',
REMOTE_PORT=62222,
UNIX_SOCKET='/tmp/ssh_tunnel.sock',
KNOWN_HOSTS='/path/to/specific_known_host_to_conflicts',
)
def start():
return call(
[
'ssh', CONFIG['SSH_SERVER'],
'-Nfi', CONFIG['SSH_KEY'],
'-MS', CONFIG['UNIX_SOCKET'],
'-o', 'UserKnownHostsFile=%s' % CONFIG['KNOWN_HOSTS'],
'-o', 'ExitOnForwardFailure=yes',
'-p', str(CONFIG['SSH_PORT']),
'-l', CONFIG['SSH_USER'],
'-R', '%d:localhost:22' % CONFIG['REMOTE_PORT']
],
stdout=DEVNULL,
stderr=STDOUT
) == 0
def stop():
return __control_ssh('exit') == 0
def status():
return __control_ssh('check') == 0
def __control_ssh(command):
return call(
['ssh', '-S', CONFIG['UNIX_SOCKET'], '-O', command, 'x'],
stdout=DEVNULL,
stderr=STDOUT
)
-o ExitOnForwardFailure=yes makes sure the ssh command will fail if the tunnel cannot be established, otherwise it will not exit.

Might I suggest trying something like pyngrok to programmatically manage an ngrok tunnel for you? Full disclosure, I am the developer of it. SSH example here, but it's as easy as installing pyngrok:
pip install pyngrok
and using it:
from pyngrok import ngrok
# <NgrokTunnel: "tcp://0.tcp.ngrok.io:12345" -> "localhost:22">
ssh_tunnel = ngrok.connect(22, "tcp")

I used paramiko for some project I had a year ago, here is the part of my code where I connected with another computer/server and executed a simple python file:
import paramiko
ssh = paramiko.SSHClient()
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
ssh.connect(hostname='...', username='...', password='...')
stdin, stdout, stderr = ssh.exec_command('python hello.py')
ssh.close()
stdin, stdout and sdterr contain the inputs/outputs of the command you executed.
From here, I think you can make the connection with the database.
Here is some good information about paramiko.