Lua Requires Chilkat v9.5.0.55+

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 used to accomplish this task.

Lua

local chilkat = require("chilkat")

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

local ssh1 = chilkat.Ssh.new()

-- Connect directly to the 1st SSH server.
local success = ssh1:connect("serverssh1.com", 22)
if not success then
    print(ssh1.last_error_text)
    return
end

-- Authenticate using login/password:
success = ssh1:authenticate_pw("ssh1Login", "ssh1Password")
if not success then
    print(ssh1.last_error_text)
    return
end

-- 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.
local ssh2 = chilkat.Ssh.new()
success = ssh2:connect_through_ssh(ssh1, "serverssh2.com", 22)
if not success then
    print(ssh2.last_error_text)
    return
end

-- Authenticate with ssh2...
success = ssh2:authenticate_pw("ssh2Login", "ssh2Password")
if not success then
    print(ssh2.last_error_text)
    return
end

local 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
success = mailman:use_ssh(ssh2)
if not success then
    print(mailman.last_error_text)
    return
end

-- Set the SMTP server.
mailman.smtp_host = "smtp.someserver.com"

-- Set the SMTP login/password (if required)
mailman.smtp_username = "myUsername"
mailman.smtp_password = "myPassword"

-- Create a new email object
local email = chilkat.Email.new()

email.subject = "This is a test"
email.body = "This is a test"
email.from = "Chilkat Support <support@chilkatsoft.com>"
success = email:add_to("Chilkat Admin", "admin@chilkatsoft.com")

success = mailman:send_email(email)
if not success then
    print(mailman.last_error_text)
    return
end

-- Close the connection with the server.  This closes the tunnel through ssh2.
success = mailman:close_smtp_connection()
if not success then
    print("Connection to SMTP server not closed cleanly.")
end

print("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()