Node.js

TCP or TLS over Multiple Hop SSH to Remote Server

See more Socket/SSL/TLS Examples

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.

Node.js

NODEJS_PRELUDE

function chilkatExample() {

    var success = false;

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

    var ssh1 = new chilkat.Ssh();

    //  Connect directly to the 1st SSH server.
    success = ssh1.Connect("serverssh1.com",22);
    if (success !== true) {
        console.log(ssh1.LastErrorText);
        return;
    }

    //  Authenticate using login/password:
    success = ssh1.AuthenticatePw("ssh1Login","ssh1Password");
    if (success !== true) {
        console.log(ssh1.LastErrorText);
        return;
    }

    //  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.
    var ssh2 = new chilkat.Ssh();
    success = ssh2.ConnectThroughSsh(ssh1,"serverssh2.com",22);
    if (success !== true) {
        console.log(ssh2.LastErrorText);
        return;
    }

    //  Authenticate with ssh2...
    success = ssh2.AuthenticatePw("ssh2Login","ssh2Password");
    if (success !== true) {
        console.log(ssh2.LastErrorText);
        return;
    }

    var socket = new chilkat.Socket();

    //  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 !== true) {
        console.log(socket.LastErrorText);
        return;
    }

    //  Connect using TLS to www.chilkatsoft.com
    //  We could also tunnel a bare TCP connection by specifying port 80 with useTls = false.
    var useTls = true;
    var maxWaitMillisec = 20000;
    success = socket.Connect("www.chilkatsoft.com",443,useTls,maxWaitMillisec);
    if (success !== true) {
        console.log(socket.LastErrorText);
        return;
    }

    //  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.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 !== true) {
        console.log(socket.LastErrorText);
        return;
    }

    //  Wait a maximum of 4 seconds while no data is forthcoming:
    socket.MaxReadIdleMs = 4000;

    //  Get the 1st response line, which should be "HTTP/1.1 200 OK"
    var responseStatusLine = socket.ReceiveToCRLF();
    if (socket.LastMethodSuccess !== true) {
        console.log(socket.LastErrorText);
        return;
    }

    console.log("StatusLine: " + responseStatusLine);

    //  Now get the 1st line of the response header:
    var responseHeaderLine = socket.ReceiveToCRLF();
    if (socket.LastMethodSuccess !== true) {
        console.log(socket.LastErrorText);
        return;
    }

    console.log("HeaderLine: " + responseHeaderLine);

    //  Now read the remainder of the response header by reading until a double CRLF is seen:
    var remainderOfHeader = socket.ReceiveUntilMatch("\r\n\r\n");
    if (socket.LastMethodSuccess !== true) {
        console.log(socket.LastErrorText);
        return;
    }

    console.log("Remainder: " + remainderOfHeader);

    //  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();

}

chilkatExample();