Perl

Connect to an SSH Server Through Another (Jump Host)

Demonstrates the Chilkat Ssh.ConnectThroughSsh method, which connects to a second SSH server through an already connected and authenticated Ssh object. The first argument is the first (jump-host) Ssh object, and the second and third are the destination hostname and port.

Background: This is SSH chaining through a "jump host" (bastion): the application connects to a reachable gateway, then tunnels onward to a target that is only accessible from inside the network. Each hop is authenticated separately with its own credentials. The result is a normal Ssh object for the target that happens to be routed through the first connection.

Chilkat Perl Downloads

Download Chilkat for Perl

Perl

use chilkat();

$success = 0;

#  Demonstrates the Ssh.ConnectThroughSsh method, which connects to a second SSH server through
#  an already connected and authenticated Ssh object (a jump host).  The 1st argument is the
#  first Ssh object, and the 2nd and 3rd are the destination hostname and port.

$sshJump = chilkat::CkSsh->new();

#  Connect and authenticate to the first SSH server (the jump host).
$sshPort = 22;
$success = $sshJump->Connect("jump.example.com",$sshPort);
if ($success == 0) {
    print $sshJump->lastErrorText() . "\r\n";
    exit;
}

#  Normally you would not hard-code the password in source.  You should instead obtain it
#  from an interactive prompt, environment variable, or a secrets vault.
$password = "mySshPassword";

$success = $sshJump->AuthenticatePw("jumpUser",$password);
if ($success == 0) {
    print $sshJump->lastErrorText() . "\r\n";
    exit;
}

#  Connect to the target SSH server through the jump host.
$sshTarget = chilkat::CkSsh->new();
$success = $sshTarget->ConnectThroughSsh($sshJump,"target.example.com",$sshPort);
if ($success == 0) {
    print $sshTarget->lastErrorText() . "\r\n";
    exit;
}

#  Authenticate to the target server (separate credentials).
$success = $sshTarget->AuthenticatePw("targetUser",$password);
if ($success == 0) {
    print $sshTarget->lastErrorText() . "\r\n";
    exit;
}

print "Connected to the target through the jump host." . "\r\n";

$sshTarget->Disconnect();
$sshJump->Disconnect();