How to run sudo bash using python script
import subprocess
import os
sudoPassword2 = 'abcd1234'
command2 = 'sudo bash'
p2 = os.system('echo %s|sudo -S %s' % (sudoPassword2, command2))
I'm getting this error:
bash: line 1: abcd1234: command not found
when i tried to this also its giving error
import shlex
import subprocess
command1 = shlex.split('cd /home/backups')
subprocess.call(command1)
error cd no file or dir
tried also this :
import shlex
import subprocess
subprocess.call(["cd","/home","/backups"])
You can use os module
import os
os.system("sudo and the code you want to run")
in example:
import os
os.system("sudo apt-get vlc")
You are receiving this error because your command posts the password to the cli first without being asked for it. So bash will interpret it as a command which, obviously, can not be executed.
Better do os.system('sudo command') and call the script as root or via sudo. This will make sure you have the necessary privileges within the script immediately at run time.
Another reason why you definitely want to refrain from doing what you do is the necessity of having the sudo password for your machine written into the script in plain text. Never do that. It's evil.
If there is no way around you can make sudo execute a command without asking for a password by adding NOPASSWD directives to the /etc/sudoers by using the editor visudo (never use anything different) like so:
user host = (root) NOPASSWD: /sbin/shutdown
user host = (root) NOPASSWD: /sbin/reboot
But if you do make sure you know that this opens the execution of this command to anyone on the system without needing elevated rights. This can be a huge security risk.
I am working on a script that at a certain point needs to switch to the root user (executing "sudo rootsh" is the only accepted way to switch to root on our servers,) after which it will execute a certain command.
I am not sure what I am missing, but the script simply ignores the part when it should switch to root and continues executing the commands with the user that started the script.
If you check the generated whoami.txt file, you will notice that the user is not root. Please keep in mind that the user executing the script can switch to root without any issue while executing the sudo rootsh command.
Here is the code I am using:
import subprocess
def switch_user():
commands = '''
sudo rootsh
whoami > whoami.txt
sysctl -a | grep kernel.msgmni'''
process = subprocess.Popen('/bin/bash', stdin=subprocess.PIPE,
stdout=subprocess.PIPE)
out, err = process.communicate(commands.encode('utf-8'))
switch_user()
Any idea what I am doing wrong? Thanks.
Instead of Popening a subprocess to run bash, and from that opening a separate privileged shell, Popen the command sudo rootsh directly. If that succeeds (requires that the user be permitted to sudo rootsh without providing a password) then deliver the rest of the commands by communicating with the subprocess.
That would be something along these lines:
import subprocess
def switch_user():
# These shell commands will be used as input to the root shell
commands = '''whoami > whoami.txt
sysctl -a | grep kernel.msgmni'''
# Launch the root shell
process = subprocess.Popen('/usr/bin/sudo rootsh',
stdin=subprocess.PIPE, stdout=subprocess.PIPE)
# Send the shell's input to it and receive back its output
out, err = process.communicate(commands.encode('utf-8'))
switch_user()
You may need to modify that for your purposes. In particular, if your sudo command lives at a different location then you may need to modify the path to it. And I emphasize again that this approach depends on being able to obtain a root shell without providing a password. Sudo can be configured that way, but it is not the default.
I finally managed to make this work after doing a more thorough investigation with the guys from the OS team. I'll post this, maybe it would be useful for somebody in the future:
import os
os.system("sudo rootsh -i -u root 'sysctl -a | grep kernel.msgmni' > parameter_value.txt")
The key was to insert the -i and -u options:
-i [command]
The -i (simulate initial login) option runs the shell specified by the password database entry of the target user as a login
shell.
This means that login-specific resource files such as .profile or .login will be read by the shell. If a command is
specified, it is
passed to the shell for execution via the shell's -c option. If no command is specified, an interactive shell is executed.
sudo
attempts to change to that user's home directory before running the shell. The security policy shall initialize the
environment to a
minimal set of variables, similar to what is present when a user logs in. The Command Environment section in the
sudoers(5) manual documents how the -i option affects the environment in which a command is run when the sudoers policy is in use.
-u user
The -u (user) option causes sudo to run the specified command as a user other than root. To specify a uid instead
of a user name, #uid.
When running commands as a uid, many shells require that the # be escaped with a backslash ('\'). Security policies may
restrict uids
to those listed in the password database. The sudoers policy allows uids that are not in the password database as
long as the targetpw
option is not set. Other security policies may not support this.
Thank you all for your answers :)
I'm developing a Django app which runs Matlab scripts with Python's Popen class. The python script that calls Matlab scripts lives in the main folder of my Django app (with views.py). When I call the script from command line, it runs like a charm but when I make a request from the client in order to run the corresponding python script, I receive the following warning:
"< M A T L A B (R) > Copyright 1984-2018 The MathWorks, Inc. R2018a (9.4.0.813654) 64-bit (glnxa64) February 23, 2018 To get started, type one of these: helpwin, helpdesk, or demo. For product information, visit www.mathworks.com. >> [Warning: Unable to create preferences folder in /var/www/.matlab/R2018a. Preferences folder location must be writable. Using a temporary preferences folder for this MATLAB session. See the preferences documentation for more details.] >>
My app uses a Python virtual environment and it is being deployed with Apache web server.
Here is my python script that calls Matlab scripts:
import os
import subprocess as sp
import pymat_config
def pymat_run():
pwd = pymat_config.pwd_config['pwd']
cmd1 = "-r \"Arg_in = '/path/to/my/main/folder/input.txt'; Arg_out = '/path/to/my/main/folder/file.txt'; matlab_script1\""
baseCmd1 = ['/usr/local/MATLAB/R2018a/bin/matlab', '-nodesktop', '-nosplash', '-nodisplay', 'nojvm', cmd1]
os.chdir('/path/to/matlab_script1')
sudo_cmd = sp.Popen(['echo', pwd], stdout=sp.PIPE)
exec1 = sp.Popen(['sudo', '-S'] + baseCmd1, stdin=sudo_cmd.stdout, stdout=sp.PIPE, stderr=sp.PIPE)
out, err = exec1.communicate()
return out
Any suggestions ?
Finally I managed to find the solution of that issue by myself. The problem came from the kind of user who called the Matlab's script. When I was running the above script from a Python interpreter or from the shell, it was the user (with the user password) who was running the script while when I was calling the script from the client the user was the web server's user: www-data.
So at first to avoid the above warning I gave permissions to www-data user to the /var/www folder with the following command:
sudo chown -R www-data /var/www/
After that, the "Warning" disappeared but the script still didn't run because it was asking for www-data's password internally and taking user's password from pymat_config file.
To solve this, I edited /etc/sudoers file in order for www-data to be able to call Matlab scripts without asking password. So I added the following line:
www-data ALL=(ALL) NOPASSWD: /usr/local/MATLAB/R2018a/bin/matlab
and now it runs like a charm !
This is a beginner level question for anyone pro in subprocess.
In Windows, is it possible for me to send the following CMD commands using subprocesssuch that they are executed one after another in a single shell:
cd C:\Users\User\myvirtualenvs\project1
Scripts\activate.bat
Hello.py
Effectively, I am trying to load the Virtualenv without having to manually myself touch CMD prompt.
Thanks in advance :)
Just like mentioned in the Comment with &&:
from subprocess import call
call(r'cd C:\ && echo 123 && dir', shell=True)
Please notice the shell=True argument.
Edit due to comment:
Shell=True is an security issue, if you're passing raw input values to the call. See this example from the docs:
from subprocess import call
filename = input("What file would you like to display?\n")
>>> What file would you like to display?
>>> non_existent; rm -rf / #
call("cat " + filename, shell=True) # Uh-oh. This will end badly...
In initially thought you want to make a small script for personal purposes. If you want to give this code away, think about packaging your code via distutils or setuptools.
I'm trying to write a small script to mount a VirtualBox shared folder each time I execute the script. I want to do it with Python, because I'm trying to learn it for scripting.
The problem is that I need privileges to launch mount command. I could run the script as sudo, but I prefer it to make sudo by its own.
I already know that it is not safe to write your password into a .py file, but we are talking about a virtual machine that is not critical at all: I just want to click the .py script and get it working.
This is my attempt:
#!/usr/bin/env python
import subprocess
sudoPassword = 'mypass'
command = 'mount -t vboxsf myfolder /home/myuser/myfolder'
subprocess.Popen('sudo -S' , shell=True,stdout=subprocess.PIPE)
subprocess.Popen(sudoPassword , shell=True,stdout=subprocess.PIPE)
subprocess.Popen(command , shell=True,stdout=subprocess.PIPE)
My python version is 2.6
Many answers focus on how to make your solution work, while very few suggest that your solution is a very bad approach. If you really want to "practice to learn", why not practice using good solutions? Hardcoding your password is learning the wrong approach!
If what you really want is a password-less mount for that volume, maybe sudo isn't needed at all! So may I suggest other approaches?
Use /etc/fstab as mensi suggested. Use options user and noauto to let regular users mount that volume.
Use Polkit for passwordless actions: Configure a .policy file for your script with <allow_any>yes</allow_any> and drop at /usr/share/polkit-1/actions
Edit /etc/sudoers to allow your user to use sudo without typing your password. As #Anders suggested, you can restrict such usage to specific commands, thus avoiding unlimited passwordless root priviledges in your account. See this answer for more details on /etc/sudoers.
All the above allow passwordless root privilege, none require you to hardcode your password. Choose any approach and I can explain it in more detail.
As for why it is a very bad idea to hardcode passwords, here are a few good links for further reading:
Why You Shouldn’t Hard Code Your Passwords When Programming
How to keep secrets secret
(Alternatives to Hardcoding Passwords)
What's more secure? Hard coding credentials or storing them in a database?
Use of hard-coded credentials, a dangerous programming error: CWE
Hard-coded passwords remain a key security flaw
sudoPassword = 'mypass'
command = 'mount -t vboxsf myfolder /home/myuser/myfolder'
p = os.system('echo %s|sudo -S %s' % (sudoPassword, command))
Try this and let me know if it works. :-)
And this one:
os.popen("sudo -S %s"%(command), 'w').write('mypass')
To pass the password to sudo's stdin:
#!/usr/bin/env python
from subprocess import Popen, PIPE
sudo_password = 'mypass'
command = 'mount -t vboxsf myfolder /home/myuser/myfolder'.split()
p = Popen(['sudo', '-S'] + command, stdin=PIPE, stderr=PIPE,
universal_newlines=True)
sudo_prompt = p.communicate(sudo_password + '\n')[1]
Note: you could probably configure passwordless sudo or SUDO_ASKPASS command instead of hardcoding your password in the source code.
Use -S option in the sudo command which tells to read the password from 'stdin' instead of the terminal device.
Tell Popen to read stdin from PIPE.
Send the Password to the stdin PIPE of the process by using it as an argument to communicate method. Do not forget to add a new line character, '\n', at the end of the password.
sp = Popen(cmd , shell=True, stdin=PIPE)
out, err = sp.communicate(_user_pass+'\n')
subprocess.Popen creates a process and opens pipes and stuff. What you are doing is:
Start a process sudo -S
Start a process mypass
Start a process mount -t vboxsf myfolder /home/myuser/myfolder
which is obviously not going to work. You need to pass the arguments to Popen. If you look at its documentation, you will notice that the first argument is actually a list of the arguments.
I used this for python 3.5. I did it using subprocess module.Using the password like this is very insecure.
The subprocess module takes command as a list of strings so either create a list beforehand using split() or pass the whole list later. Read the documentation for moreinformation.
#!/usr/bin/env python
import subprocess
sudoPassword = 'mypass'
command = 'mount -t vboxsf myfolder /home/myuser/myfolder'.split()
cmd1 = subprocess.Popen(['echo',sudoPassword], stdout=subprocess.PIPE)
cmd2 = subprocess.Popen(['sudo','-S'] + command, stdin=cmd1.stdout, stdout=subprocess.PIPE)
output = cmd2.stdout.read.decode()
sometimes require a carriage return:
os.popen("sudo -S %s"%(command), 'w').write('mypass\n')
Please try module pexpect. Here is my code:
import pexpect
remove = pexpect.spawn('sudo dpkg --purge mytool.deb')
remove.logfile = open('log/expect-uninstall-deb.log', 'w')
remove.logfile.write('try to dpkg --purge mytool\n')
if remove.expect(['(?i)password.*']) == 0:
# print "successfull"
remove.sendline('mypassword')
time.sleep(2)
remove.expect(pexpect.EOF,5)
else:
raise AssertionError("Fail to Uninstall deb package !")
To limit what you run as sudo, you could run
python non_sudo_stuff.py
sudo -E python -c "import os; os.system('sudo echo 1')"
without needing to store the password. The -E parameter passes your current user's env to the process. Note that your shell will have sudo priveleges after the second command, so use with caution!
I know it is always preferred not to hardcode the sudo password in the script. However, for some reason, if you have no permission to modify /etc/sudoers or change file owner, Pexpect is a feasible alternative.
Here is a Python function sudo_exec for your reference:
import platform, os, logging
import subprocess, pexpect
log = logging.getLogger(__name__)
def sudo_exec(cmdline, passwd):
osname = platform.system()
if osname == 'Linux':
prompt = r'\[sudo\] password for %s: ' % os.environ['USER']
elif osname == 'Darwin':
prompt = 'Password:'
else:
assert False, osname
child = pexpect.spawn(cmdline)
idx = child.expect([prompt, pexpect.EOF], 3)
if idx == 0: # if prompted for the sudo password
log.debug('sudo password was asked.')
child.sendline(passwd)
child.expect(pexpect.EOF)
return child.before
It works in python 2.7 and 3.8:
from subprocess import Popen, PIPE
from shlex import split
proc = Popen(split('sudo -S %s' % command), bufsize=0, stdout=PIPE, stdin=PIPE, stderr=PIPE)
proc.stdin.write((password +'\n').encode()) # write as bytes
proc.stdin.flush() # need if not bufsize=0 (unbuffered stdin)
without .flush() password will not reach sudo if stdin buffered.
In python 2.7 Popen by default used bufsize=0 and stdin.flush() was not needed.
For secure using, create password file in protected directory:
mkdir --mode=700 ~/.prot_dir
nano ~/.prot_dir/passwd.txt
chmod 600 ~/.prot_dir/passwd.txt
at start your py-script read password from ~/.prot_dir/passwd.txt
with open(os.environ['HOME'] +'/.prot_dir/passwd.txt') as f:
password = f.readline().rstrip()
import os
os.system("echo TYPE_YOUR_PASSWORD_HERE | sudo -S TYPE_YOUR_LINUX_COMMAND")
Open your ide and run the above code. Please change TYPE_YOUR_PASSWORD_HERE and TYPE_YOUR_LINUX_COMMAND to your linux admin password and your desired linux command after that run your python script. Your output will show on terminal. Happy Coding :)
You can use SSHScript . Below are example codes:
## filename: example.spy
sudoPassword = 'mypass'
command = 'mount -t vboxsf myfolder /home/myuser/myfolder'
$$echo #{sudoPassword} | sudo -S #{command}
or, simply one line (almost the same as running on console)
## filename: example.spy
$$echo mypass | sudo -S mount -t vboxsf myfolder /home/myuser/myfolder
Then, run it on console
sshscript example.spy
Where "sshscript" is the CLI of SSHScript (installed by pip).
solution im going with,because password in plain txt in an env file on dev pc is ok, and variable in the repo and gitlab runner is masked.
use .dotenv put pass in .env on local machine, DONT COMMIT .env to git.
add same var in gitlab variable
.env file has:
PASSWORD=superpass
from dotenv import load_dotenv
load_dotenv()
subprocess.run(f'echo {os.getenv("PASSWORD")} | sudo -S rm /home//folder/filetodelete_created_as_root.txt', shell=True, check=True)
this works locally and in gitlab. no plain password is committed to repo.
yes, you can argue running a sudo command w shell true is kind of crazy, but if you have files written to host from a docker w root, and you need to pro-grammatically delete them, this is functional.