3

I use two factor authentication for OpenVPN, and I am doing that using the static-challenge directive.

I also want to store my VPN username and password.

I tried doing this using auth-user-password up per the man page, but when I do that, it doesn't give me an opportunity to offer a static-challenge, so that fails.

I tried writing a python script that would pass a username, password, and challenge response via stdin to the openvpn process, but openvpn doesn't seem to get any of the things I send to stdin (even though running the same code against a sample script I wrote that gets input using sys.stdin.readline() worked). A snippet is below.

openvpn = subprocess.Popen(                                                      
        ['openvpn', '--config', os.path.expanduser('~/.ovpn-config')],           
        stdin=subprocess.PIPE)                                                   
openvpn.communicate('%s\n%s\n%s\n' % (username, password, otp))                  

Any thoughts on how to both store the username and password and use a static challenge?

Thanks!

3

I guess the problem is, that the username and password are not sent via stdin!

You should take a look at the python module "pexpect".

0

You have to use a pseudo tty:

#!/usr/bin/env python

import os
import sys
import pty
import subprocess

K = "GOOGLEAUTHKEY"
OVPN = "client.ovpn"
CHALLENGE = "CHALLENGE"

p = subprocess.Popen(["oathtool", "--totp", "-b", K], stdout=subprocess.PIPE)
code = p.stdout.read().strip()

cp, fd = pty.fork()
if cp == 0:
    os.execlp("openvpn", "openvpn", "--config", OVPN)
else:
    f = os.fdopen(fd)
    challenge = False
    while not challenge:
        l = os.read(fd, len(CHALLENGE))
        challenge = l == CHALLENGE
        if not challenge:
            f.readline()
    os.write(fd, "%s\n" % code)
    while True:
        try:
            print f.readline().strip()
        except KeyboardInterrupt:
            os.kill(cp, 15)
        except IOError:
            print "Bye"
            sys.exit(0)

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