Perl Requires Chilkat v11.0.0+

SSH Tunnel Inside another SSH Tunnel

See more SSH Tunnel Examples

Demonstrates how to create a TCP/IP socket connection through an SSH tunnel that is dynamic port forwarded through another SSH tunnel. Perl

use chilkat();

$success = 0;

#  This example requires the Chilkat API to have been previously unlocked.
#  See Global Unlock Sample for sample code.

$tunnel = chilkat::CkSshTunnel->new();

$sshHostname = "www.ssh-serverA.com";
$sshPort = 22;

#  Connect to an SSH server and establish the SSH tunnel:
$success = $tunnel->Connect($sshHostname,$sshPort);
if ($success == 0) {
    print $tunnel->lastErrorText() . "\r\n";
    exit;
}

#  Authenticate with the SSH server via a login/password
#  or with a public key.  
#  This example demonstrates SSH password authentication.
$success = $tunnel->AuthenticatePw("mySshLogin","mySshPassword");
if ($success == 0) {
    print $tunnel->lastErrorText() . "\r\n";
    exit;
}

#  Indicate that the background SSH tunnel thread will behave as a SOCKS proxy server
#  with dynamic port forwarding:
$tunnel->put_DynamicPortForwarding(1);

#  We may optionally require that connecting clients authenticate with our SOCKS proxy server.
#  To do this, set an inbound username/password.  Any connecting clients would be required to 
#  use SOCKS5 with the correct username/password.
#  If no inbound username/password is set, then our SOCKS proxy server will accept both
#  SOCKS4 and SOCKS5 unauthenticated connections.

$tunnel->put_InboundSocksUsername("chilkat123");
$tunnel->put_InboundSocksPassword("password123");

#  Start the listen/accept thread to begin accepting SOCKS proxy client connections.
#  Listen on port 1080.
$success = $tunnel->BeginAccepting(1080);
if ($success == 0) {
    print $tunnel->lastErrorText() . "\r\n";
    exit;
}

#  Now that a background thread is running a SOCKS proxy server that forwards connections
#  through an SSH tunnel, it is possible to use any Chilkat implemented protocol that is SOCKS capable,
#  such as HTTP, POP3, SMTP, IMAP, FTP, Socket, etc.  The protocol may use SSL/TLS because the SSL/TLS
#  will be passed through the SSH tunnel to the end-destination.  Also, any number of simultaneous
#  connections may be routed through the SSH tunnel.

$tunnelB = chilkat::CkSocket->new();

#  Indicate that the socket object is to use our portable SOCKS proxy/SSH tunnel running in our background thread.
$tunnelB->put_SocksHostname("localhost");
$tunnelB->put_SocksPort(1080);
$tunnelB->put_SocksVersion(5);
$tunnelB->put_SocksUsername("chilkat123");
$tunnelB->put_SocksPassword("password123");

#  Open a new SSH tunnel through the existing tunnel (via what we treat as a SOCKS5 proxy,
#  but it is actually a dynamic port-forwarded SSH tunnel).
$success = $tunnelB->SshOpenTunnel("www.ssh-serverB.com",22);
if ($success == 0) {
    print $tunnelB->lastErrorText() . "\r\n";
    exit;
}

#  Authenticate with ssh-serverB.com
$success = $tunnelB->SshAuthenticatePw("uname","pwd");
if ($success == 0) {
    print $tunnelB->lastErrorText() . "\r\n";
    exit;
}

#  OK, the SSH tunnel (within a tunnel) is setup.  Now open a channel within the tunnel.
#  Once the channel is obtained, the Socket API may
#  be used exactly the same as usual, except all communications
#  are sent through the channel in the SSH tunnel.
#  Any number of channels may be created from the same SSH tunnel.
#  Multiple channels may coexist at the same time.

#  Connect to an NIST time server and read the current date/time
$channel = chilkat::CkSocket->new();
$maxWaitMs = 4000;
$useTls = 0;
$success = $tunnelB->SshNewChannel("time-c.nist.gov",37,$useTls,$maxWaitMs,$channel);
if ($success == 0) {
    print $tunnelB->lastErrorText() . "\r\n";
    exit;
}

#  The time server will send a big-endian 32-bit integer representing
#  the number of seconds since since 00:00 (midnight) 1 January 1900 GMT.
#  The ReceiveInt32 method will receive a 4-byte integer, but returns
#  1 or 0 to indicate success.  If successful, the integer
#  is obtained via the ReceivedInt property.
$bigEndian = 1;
$success = $channel->ReceiveInt32($bigEndian);
if ($success == 0) {
    print $channel->lastErrorText() . "\r\n";
    exit;
}

$dt = chilkat::CkDateTime->new();
$dt->SetFromNtpTime($channel->get_ReceivedInt());

#  Show the current local date/time
$bLocalTime = 1;
print "Current local date/time: " . $dt->getAsRfc822($bLocalTime) . "\r\n";

#  Close the SSH channel.
$success = $channel->Close($maxWaitMs);
if ($success == 0) {
    print $channel->lastErrorText() . "\r\n";
    exit;
}

#  Stop the background listen/accept thread:
$waitForThreadExit = 1;
$success = $tunnel->StopAccepting($waitForThreadExit);
if ($success == 0) {
    print $tunnel->lastErrorText() . "\r\n";
    exit;
}

#  Close the SSH tunnel (would also kick any remaining connected clients).
$success = $tunnel->CloseTunnel($waitForThreadExit);
if ($success == 0) {
    print $tunnel->lastErrorText() . "\r\n";
    exit;
}