Rust

SMTP over Multiple Hop SSH

Demonstrates how to send email (using TCP or TLS) tunneled through mulitple-hop SSH. The scheme looks like this:

Application => ServerSSH1 => ServerSSH2 => SmtpServer

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

Rust

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

let ssh1 = chilkat::Ssh::new();

// Connect directly to the 1st SSH server.
if ssh1.connect("serverssh1.com", 22).is_err() {
    println!("{}", ssh1.last_error_text());
    return;
}

// Authenticate using login/password:
if ssh1.authenticate_pw("ssh1Login", "ssh1Password").is_err() {
    println!("{}", ssh1.last_error_text());
    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.
let ssh2 = chilkat::Ssh::new();
if ssh2.connect_through_ssh(&ssh1, "serverssh2.com", 22).is_err() {
    println!("{}", ssh2.last_error_text());
    return;
}

// Authenticate with ssh2...
if ssh2.authenticate_pw("ssh2Login", "ssh2Password").is_err() {
    println!("{}", ssh2.last_error_text());
    return;
}

let mailman = chilkat::MailMan::new();

// Tell the mailman object to connect to the SMTP server though the ssh2 tunnel (which itself is routed through ssh1).
// The connection looks like this:  Application => ServerSSH1 => ServerSSH2 => SMTPServer
if mailman.use_ssh(&ssh2).is_err() {
    println!("{}", mailman.last_error_text());
    return;
}

// Set the SMTP server.
mailman.set_smtp_host("smtp.someserver.com");

// Set the SMTP login/password (if required)
mailman.set_smtp_username("myUsername");
mailman.set_smtp_password("myPassword");

// Create a new email object
let email = chilkat::Email::new();

email.set_subject("This is a test");
email.set_body("This is a test");
email.set_from("Chilkat Support <support@chilkatsoft.com>");
let _ = email.add_to("Chilkat Admin", "admin@chilkatsoft.com").is_ok();

if mailman.send_email(&email).is_err() {
    println!("{}", mailman.last_error_text());
    return;
}

// Close the connection with the server.  This closes the tunnel through ssh2.
if mailman.close_smtp_connection().is_err() {
    println!("Connection to SMTP server not closed cleanly.");
}

println!("Mail Sent!");

// 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();