(Perl) TCP or TLS over Multiple Hop SSH to Remote Server

Demonstrates how to use the Chilkat Socket API to connect to a remote server (using TCP or TLS) tunneled through mulitple-hop SSH. The scheme looks like this:

Application => ServerSSH1 => ServerSSH2 => DestinationServer

The ConnectThroughSsh and UseSsh methods are added in Chilkat version 9.5.0.55 to accomplish this task.

Chilkat Perl Downloads Perl Module for Windows, MacOS, Linux, Alpine Linux, Solaris

use chilkat();

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

$ssh1 = chilkat::CkSsh->new();

# Connect directly to the 1st SSH server.
$success = $ssh1->Connect("serverssh1.com",22);
if ($success != 1) {
    print $ssh1->lastErrorText() . "\r\n";
    exit;
}

# Authenticate using login/password:
$success = $ssh1->AuthenticatePw("ssh1Login","ssh1Password");
if ($success != 1) {
    print $ssh1->lastErrorText() . "\r\n";
    exit;
}

# Connect through the 1st SSH connection to reach a 2nd SSH server.
# Note: Any number of SSH connections may be simultaneously tunneled through a single
# existing SSH connection.
$ssh2 = chilkat::CkSsh->new();
$success = $ssh2->ConnectThroughSsh($ssh1,"serverssh2.com",22);
if ($success != 1) {
    print $ssh2->lastErrorText() . "\r\n";
    exit;
}

# Authenticate with ssh2...
$success = $ssh2->AuthenticatePw("ssh2Login","ssh2Password");
if ($success != 1) {
    print $ssh2->lastErrorText() . "\r\n";
    exit;
}

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

# Tell the socket object to connect to our destination server though the ssh2 tunnel (which itself is routed through ssh1).
# The connection looks like this:  ApplicationSocket(TLS) => ServerSSH1 => ServerSSH2 => DestinationServer
$success = $socket->UseSsh($ssh2);
if ($success != 1) {
    print $socket->lastErrorText() . "\r\n";
    exit;
}

# Connect using TLS to www.chilkatsoft.com
# We could also tunnel a bare TCP connection by specifying port 80 with useTls = 0.
$useTls = 1;
$maxWaitMillisec = 20000;
$success = $socket->Connect("www.chilkatsoft.com",443,$useTls,$maxWaitMillisec);
if ($success != 1) {
    print $socket->lastErrorText() . "\r\n";
    exit;
}

# Once the multiple hop SSH tunneled connection is setup,  the socket programming
# is identical to the normal case where we have a direct connection.

# Tell the socket object that all text is to be sent in the utf-8 encoding,
# and the text received is assumed to be utf-8.
$socket->put_StringCharset("utf-8");

# Send an HTTP HEAD request:
$success = $socket->SendString("HEAD / HTTP/1.1\r\nHost: www.chilkatsoft.com\r\n\r\n");
if ($success != 1) {
    print $socket->lastErrorText() . "\r\n";
    exit;
}

# Wait a maximum of 4 seconds while no data is forthcoming:
$socket->put_MaxReadIdleMs(4000);

# Get the 1st response line, which should be "HTTP/1.1 200 OK"
$responseStatusLine = $socket->receiveToCRLF();
if ($socket->get_LastMethodSuccess() != 1) {
    print $socket->lastErrorText() . "\r\n";
    exit;
}

print "StatusLine: " . $responseStatusLine . "\r\n";

# Now get the 1st line of the response header:
$responseHeaderLine = $socket->receiveToCRLF();
if ($socket->get_LastMethodSuccess() != 1) {
    print $socket->lastErrorText() . "\r\n";
    exit;
}

print "HeaderLine: " . $responseHeaderLine . "\r\n";

# Now read the remainder of the response header by reading until a double CRLF is seen:
$remainderOfHeader = $socket->receiveUntilMatch("\r\n\r\n");
if ($socket->get_LastMethodSuccess() != 1) {
    print $socket->lastErrorText() . "\r\n";
    exit;
}

print "Remainder: " . $remainderOfHeader . "\r\n";

# Close the connection with the server.  This closes the tunnel through ssh2.
# Wait a max of 20 seconds (20000 millsec)
$success = $socket->Close(20000);

# Close the connection with ssh2.  (This closes the the tunnel through ssh1.)
# The connection with ssh1 is still alive, and may be used for more connections.
$ssh2->Disconnect();

$ssh1->Disconnect();