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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.

Zig

const std = @import("std");
const chilkat = @import("chilkat");

pub fn main(init: std.process.Init) !void {
    const alloc = init.arena.allocator();

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

    const ssh1 = try chilkat.Ssh.init();
    defer ssh1.deinit();

    // Connect directly to the 1st SSH server.
    ssh1.connect("serverssh1.com", 22) catch {
        std.debug.print("{s}\n", .{try ssh1.getLastErrorText(alloc)});
        return;
    };

    // Authenticate using login/password:
    ssh1.authenticatePw("ssh1Login", "ssh1Password") catch {
        std.debug.print("{s}\n", .{try ssh1.getLastErrorText(alloc)});
        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.
    const ssh2 = try chilkat.Ssh.init();
    defer ssh2.deinit();
    ssh2.connectThroughSsh(ssh1, "serverssh2.com", 22) catch {
        std.debug.print("{s}\n", .{try ssh2.getLastErrorText(alloc)});
        return;
    };

    // Authenticate with ssh2...
    ssh2.authenticatePw("ssh2Login", "ssh2Password") catch {
        std.debug.print("{s}\n", .{try ssh2.getLastErrorText(alloc)});
        return;
    };

    const socket = try chilkat.Socket.init();
    defer socket.deinit();

    // 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
    socket.useSsh(ssh2) catch {
        std.debug.print("{s}\n", .{try socket.getLastErrorText(alloc)});
        return;
    };

    // Connect using TLS to www.chilkatsoft.com
    // We could also tunnel a bare TCP connection by specifying port 80 with useTls = false.
    const use_tls = true;
    const max_wait_millisec = 20000;
    socket.connect("www.chilkatsoft.com", 443, use_tls, max_wait_millisec) catch {
        std.debug.print("{s}\n", .{try socket.getLastErrorText(alloc)});
        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.setStringCharset("utf-8");

    // Send an HTTP HEAD request:
    socket.sendString("HEAD / HTTP/1.1\r\nHost: www.chilkatsoft.com\r\n\r\n") catch {
        std.debug.print("{s}\n", .{try socket.getLastErrorText(alloc)});
        return;
    };

    // Wait a maximum of 4 seconds while no data is forthcoming:
    socket.setMaxReadIdleMs(4000);

    // Get the 1st response line, which should be "HTTP/1.1 200 OK"
    const response_status_line = socket.receiveToCRLF(alloc) catch {
        std.debug.print("{s}\n", .{try socket.getLastErrorText(alloc)});
        return;
    };

    std.debug.print("StatusLine: {s}\n", .{response_status_line});

    // Now get the 1st line of the response header:
    const response_header_line = socket.receiveToCRLF(alloc) catch {
        std.debug.print("{s}\n", .{try socket.getLastErrorText(alloc)});
        return;
    };

    std.debug.print("HeaderLine: {s}\n", .{response_header_line});

    // Now read the remainder of the response header by reading until a double CRLF is seen:
    const remainder_of_header = socket.receiveUntilMatch(alloc, "\r\n\r\n") catch {
        std.debug.print("{s}\n", .{try socket.getLastErrorText(alloc)});
        return;
    };

    std.debug.print("Remainder: {s}\n", .{remainder_of_header});

    // Close the connection with the server.  This closes the tunnel through ssh2.
    // Wait a max of 20 seconds (20000 millsec)
    try 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();
}