Use Powershell and SSH-Sessions to launch openconnect VPN - linux

I need to launch an openconnect VPN on a linux router from a powershell script on Windows.
I have a working script on the linux router:
echo PASSWORD | sudo openconnect -b --no-dtls --interface=sslvpn host.isp.com --authgroup=SharedVPN --user=username --passwd-on-stdin
When I run the script locally on the router, the vpn launches perfectly.
Here is my powershell script from the windows machine:
Import-Module SSH-Sessions
New-SshSession -ComputerName "10.1.43.11" -Username "ubuntu" -KeyFile "C:\keys.pem"
Invoke-SshCommand -ComputerName "10.1.43.11" -Command '/usr/local/sbin/InitializeVPN'
Remove-SshSession -computername "10.1.43.11"
When I run the powershell script, it does launch the VPN, but freezes there, waiting for the VPN to end. I can kill the process on the router and then the powershell script finishes. I need the VPN to run in the background. So I modified the script on the router like this:
echo PASSWORD | sudo openconnect -b --no-dtls --interface=sslvpn host.isp.com --authgroup=SharedVPN --user=username --passwd-on-stdin &
Now when I run the powershell script, it does seem to send it into the background, but the VPN doesn't stay up and I only get partial output to the screen:
Key file specified. Will override password. Trying to read key file...
Successfully connected to 10.1.43.11
10.1.43.11: POST https://host.isp.com/
Connected to ip_addr:443
SSL negotiation with host.isp.com
Connected to HTTPS on host.isp.com
XML POST enabled
POST https://host.isp.com/
Connected to ip_addr:443
SSL negotiation with host.isp.com
Connected to HTTPS on host.isp.com
XML POST enabled
10.1.43.11 should now be disconnected and disposed.
When I run it directly on the router, there is more after the last "XML POST enabled":
Please enter your username and password.
POST https://host.isp.com/
Got CONNECT response: HTTP/1.1 200 OK
CSTP connected. DPD 30, Keepalive 20
Connected as 10.251.0.29, using SSL
Continuing in background; pid 11049
Connect Banner:
| Access to this system is restricted to authorized users. Unauthorized use is strictly prohibited. Information on this system may be intercepted, recorded, read, copied, and disclosed by and to authorized personnel for official purposes, including criminal investigations. Access or use of this system whether authorized or unauthorized, constitutes your awareness and consent to these terms. DISCONNECT IMMEDIATELY if you do not agree to the conditions stated in this warning.
|
How do I get the VPN to launch in the background?
I'm using ubuntu 16.04, openconnect 7.08, powershell 5.1, windows server 2016,
downloaded SSH-Sessions from http://www.powershelladmin.com/wiki/SSH_from_PowerShell_using_the_SSH.NET_library#Downloads

Well, I got it working using plink:
C:\bin\plink.exe -i C:\key.ppk ubuntu#10.1.43.11 "nohup /usr/local/sbin/InitializeVPN >/home/ubuntu/VPN.out 2>/home/ubuntu/VPN.err </dev/null &"
stdin, stdout, and stderr had to be redirected and use nohup.
I found it here: Getting ssh to execute a command in the background on target machine
Don't know if I'll take the time to get it working with PowerShell and SSH-Sessions now. Maybe if I need something more complex in the future.

Related

Rsync from Linux to Windows SFTP Server

I'm trying to sync documents to an Windows SFTP server via RSYNC on a Linux Machine.
This is my command
rsync -e ssh /home/antony/Documents/Test user1#172.20.1.18:Test
This is the error
exec request failed on channel 0
rsync connection unexpectedly closed (0 bytes recieved so far)[sender]
rsync error: unexplained error (code 255) at io.c(226) [sender=3.1.0]
The above may happen for several different reasons.
Maybe the SSH subsystem of rsync is refusing the server key, but this is unlikely because from your description seems like the server is "cutting" the connection, not the client.
Another possibility is that there is no SSH/SFTP server listening on the default port on 172.20.1.18
Or maybe password authentication is not enabled on the server, and you need to authenticate via PKI using a key that you (on the client side) do not have...
In any case, the best thing to do is to double check with the administrator who has configured the server side.

Cant connect to FTP with newly created account

I am trying to connect to a new user account I created via SSH with the command
useradd -s /bin/false -d /home/username james
I added/edited the password via SSH with the command
passwd james
When trying to connect to my server using this user and pass via FileZilla I get the following error messages.
Response: 331 User James OK. Password required
Command: PASS *****
Response: 530 Login authentication failed
Error: Critical error
Error: Could not connect to server
When I try to login with this user/pass through SFTP I get the following error messages
Status: Connected to domain.com
Error: Connection closed by server with exitcode 1
Error: Could not connect to server
Either way it seems it doesn't allow me to use this newuser anywhere.
My server details
Linux 2.6.18-308.11.1.el5 GNU/Linux
(Red Hat 4.1.2-52)
Centos
Regarding FTP, the FTP server commonly used on Linux systems requires users to have a shell that's listed in the file /etc/shells. For example, this online ftpd man page says that, among other things, "The user must have a standard shell returned by getusershell(3).". The page for getusershell() shows that it reads shells from /etc/shells.
You could probably make FTP work adding /bin/false to /etc/shells. Your Linux system might have a more suitable shell available, like /usr/sbin/nologin.
Regarding SFTP, the ssh server normally provides SFTP service by by invoking a program called sftp-server. If you examine the server's sshd_config file, you'll probably find a line like this:
Subsystem sftp /usr/lib/openssh/sftp-server
sshd runs the subsystem program as a shell command, using the user's shell. If you set the user's shell to /bin/false, then sshd ends up running the command:
/bin/false -c /usr/lib/openssh/sftp-server
/bin/false ignores its command-line arguments and exits with code 1, so the SFTP client's session drops immediately after it starts.
sshd has an internal SFTP server component that can be used instead of the external program. The usual way of limiting SSH access to SFTP for some users is to set up a Match group within sshd_config, forcing the internal-sftp command for certain classes of users. Here are a couple examples of that:
http://en.wikibooks.org/wiki/OpenSSH/Cookbook/SFTP#SFTP-only_Accounts
https://serverfault.com/questions/354615/allow-sftp-but-disallow-ssh
Dont use "-s /bin/false". Use "-s /sbin/nologin" instead and it should be fine.
Make sure your account password hasn't expired. Mine did, and Filezilla exited with error code 1.
After logging onto the server and updating the account password (prompted immediately after connecting), I am now able to connect with SFTP & Filezilla.
Probably is a password related issue, check account
chage -l <user>
account must not be expired.
FTP doesn't allow /usr/sbin/nologin user
Response: 220 Welcome to the Scent Library's File Service.
Command: USER ftpuser
Response: 331 Please specify the password.
Command: PASS ******
Response: 530 Login incorrect.
filezilla 530 error - but password is correct
vsftpd: 530 Login incorrect
530 Login or password incorrect!
How can I connect via FTP using FileZilla? I get a 530 error.
Response: 220 Welcome to Test FTP service.
Command: USER ftpuser
Response: 331 Please specify the password.
Command: PASS ******
Response: 530 Login incorrect.
Error: Critical error
Error: Could not connect to server
Change user's shell
usermod -s /usr/sbin/nologin username
Then edit "/etc/shells" file and add this line
/usr/sbin/nologin
In order to connect to the server using ftp, you also need to run a ftp server / service or daemon.
An example of such ftp server is "vsftpd"
After installing it, you will also need to configure it and allow anonymous ftp access or ftp access to existing users
You will find the configuration file in the path "/etc/vsftpd/vsftpd.conf"
The below link might be useful for you --
https://www.digitalocean.com/community/tutorials/how-to-set-up-vsftpd-on-centos-6--2

SSH Secure Shell Tunnel X11 - Display not shown

I am using SSH Secure Shell to connect to a server. My connection is allowed to Tunnel X11 connections but when I execute the command. The display is not showing up. I get the message:
couldn't connect to display "localhost:12.0"
I have a ssh server installed and running on my machine.
Remember: Both the client and the server have to allow X forwarding.
On the server look in /etc/ssh/sshd_config and make sure you have X11Forwarding yes. You will need to restart the service if you edit this file.
On the client look in /etc/ssh/ssh_config (your user ~/.ssh/ssh/config will override global settings, if you have created this file) and make sure you have ForwardX11 yes.
Alternatively give the -X switch when you create your client connection. e.g. ssh -X user#host
Oh and of course, your client needs to be running an X server which you have authority to use! E.g. if you connect from Windows using PuTTY it will never work, as Windows is not an X server!
I figured it out. I needed to have X-Server installed on my computer instead of SSH-Server. I installed Xming for that purpose and now everything works as it should.

Executing exe or bat file on remote windows machine from *nix

I am trying to execute a bat file on remote windows machine on cloud from my Linux. The bat files starts selenium server and then my selenium tests are run. I am not able to start selenium RC server on that machine. I tried with Telnet but the problem with it is when telnet session is closed the RC server port is also closed. As my code my code has to start the server so I tried with ANT telnet task and also executed shell script of telnet in both ways the port was closed.
I read about Open SSH, psexec for linux and cygwin. But i am not getting how to use these and will they will solve my problem.
I have tried to start a service which will start the server but in this method i am not getting browser visible all tests are running in background as my script takes screen shot browser visibility is must.
Now my Question is what to use and which will be preferable for my job.
and what ever i choose should be executed by code it may be by shell, ant or php.
Thanks in advance.
Let's go through the various options you mentioned:
psexec: This is pretty much a PC only thing. Plus, you must make sure that newer Windows machines can get through the UAC that are setup by default. UAC is the thing you see all the time on Vista and Windows 7 when you try to do something that requires administrator's privileges. You can try something called winexe which is a Linux program that can do the psexec protocol, but I've had problems getting it to work.
OpenSSH: There are two main flavors of SSH, and Open SSH is the one used by the vast majority of sites. SSH has several advantages over other methods:
SSH is secure: Your network traffic is encrypted.
SSH can be password independent: You can setup SSH to use private/public keys. This way, you don't even have to know the password on the remote server. This makes it more secure since you don't have passwords being stored on various systems. And, in many Windows sites, passwords have to be changed every month or so or the account is locked.
SSH can do more than just execute remote commands: There are two sub-protocols on SSH called SCP and SFTP. These allow you to transfer files between two machines. Since they work over SSH, you get all of the advantages of SSH including encrypted packets, and public/private key protection.
SSH is well implemented in the Unix World: You'll find SSH clients built into Ant, Maven, and other build tools. Programs like CVS, Subversion, and Git can work over SSH connections too. Unfortunately, the Windows World operates in a different space time dimension. To use SSH on a Windows system requires third party software like Cygwin.
Cygwin: Cygwin is sort of an odd beast. It's a layer on top of Windows that allows many of the Unix/GNU libraries to work over Windows. It was originally developed to allow Unix developers to run their software on Windows DOS systems. However, Cygwin now contains a complete Unix like system including tools such as Perl and Python, BASH shell, and many utilities such as an SSH server. Since Cygwin is open source, you can download it for free and run SSH server. Unfortunately, I've had problems with Cygwin's SSH server. Another issue: If you're running programs remotely, you probably want to run them in a Windows environment and not the Cygwin environment.
I recommend that you look at WinSSHD from Bitvise. It's an OpenSSH implementation of the SSH Server, but it's not open source. It's about $100 per license and you need a license on each server. However, it's a robust implementation and has all of the features SSH has to offer.
You can look at CoSSH which is a package of Cygwin utilities and OpenSSH server. This is free and all open source, but if you want an easy way of setting it up, you have to pay for the Advanced Administrator Console. You don't need the Advanced Administrator Console since you can use Cygwin to set everything up, and it comes with a basic console to help.
I prefer to use cygwin and use SSH to then log in to the windows machine to execute commands. Be aware that, by default, cygwin doesn't have OpenSSH installed.
Once you have SSH working on the windows machine you can run a command on it from the Linux machine like this:
ssh user#windowsmachine 'mycommand.exe'
You can also set up ssh authentication keys so that you don't need to enter a password each time.
I've succeeded to run remote command on W2K3 via EXPECT on Debian Buster. Here is the script of mine:
#!/usr/bin/expect
#
# execute the script in the following manner:
#
# <script> <vindoze> <user> <password> <command>
#
#
set timeout 200
set hostname [lindex $argv 0]
set username [lindex $argv 1]
set password [lindex $argv 2]
set command [lindex $argv 3]
spawn telnet $hostname
expect "login:"
send "$username\r"
expect "password:"
send "$password\r"
expect "C:*"
send "dir c:\\tasks\\logs \r"
# send $command
expect "C:*"
send "exit\r\r\r"
Bear in mind that you need to enable TELNET service of the Win machine and also the user which you are authenticated with must be member of TelnetClients built-in Win group. Or as most of the Win LazyMins do - authenticate with Admin user ;)
I use similar "expect" script for automated collecting & backup configuration of CLI enabled network devices like Allied Telesyn, Cisco, Planet etc.
Cheers,
LAZA
Not a very secure way, but if you have a running webserver you can use PHP or ASP to trigger a system command. Just hide thgat script under www.myserver.com/02124309c9867a7616972f52a55db1b4.php or something. And make sure the command are fixed written in the code, not open via parameter ...

Using Psexec with Windows Server 2003

I'm trying to run a psexec command to a remote Windows Server 2003 machine. I run the following command:
psexec \machinename perfmon.msc -u machineadmin -p adminpassword -i -s
The -i and -s flags will allow me to run the GUI for perfmon.msc on the remote machine's desktop interactively.
I get the following error when I try to run the above command:
Couldn't Access machinename
Access denied
I'm using psexec version 1.94 and I'm certain that the machinename, user, and password are correct. Does anyone know if there are known issues with psexec on Windows Server 2003 and whether or not there is a fix?
[This question would be better fit for ServerFault.com, but nevertheless...]
A few suggestions:
Use two slashes before the machinename e.g. \\machinename (maybe that's what you meant the StackOverflow escaped the backslash)
*.MSC files are not usually directly executable remotely--you'll want to give the path to "c:\WINDOWS\system32\mmc.exe" and then the parameters
All parameters for psexec should go before the remote program and its parameters.
Is there really a reason to run the process as the System account ('-s') instead of just Administrator?
All together, it should look something like this:
psexec \\machinename -i -u machineadmin -p adminpassword "c:\WINDOWS\system32\mmc.exe" "perfmon.msc"
Are you connecting as an admin to the remote machine? The error says 'access denied'. You may not have the necessary privileges. Try connecting as an admin.

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