(Ruby) 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.

Chilkat Ruby Downloads install from rubygems.org gem install chilkat or download... Ruby Library for Windows, MacOS, Linux, Alpine Linux

require '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 != true)
    print ssh1.lastErrorText() + "\n";
    exit
end

# Authenticate using login/password:
success = ssh1.AuthenticatePw("ssh1Login","ssh1Password")
if (success != true)
    print ssh1.lastErrorText() + "\n";
    exit
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.
ssh2 = Chilkat::CkSsh.new()
success = ssh2.ConnectThroughSsh(ssh1,"serverssh2.com",22)
if (success != true)
    print ssh2.lastErrorText() + "\n";
    exit
end

# Authenticate with ssh2...
success = ssh2.AuthenticatePw("ssh2Login","ssh2Password")
if (success != true)
    print ssh2.lastErrorText() + "\n";
    exit
end

mailman = Chilkat::CkMailMan.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.UseSsh(ssh2)
if (success != true)
    print mailman.lastErrorText() + "\n";
    exit
end

# Set the SMTP server.
mailman.put_SmtpHost("smtp.someserver.com")

# Set the SMTP login/password (if required)
mailman.put_SmtpUsername("myUsername")
mailman.put_SmtpPassword("myPassword")

# Create a new email object
email = Chilkat::CkEmail.new()

email.put_Subject("This is a test")
email.put_Body("This is a test")
email.put_From("Chilkat Support <support@chilkatsoft.com>")
success = email.AddTo("Chilkat Admin","admin@chilkatsoft.com")

success = mailman.SendEmail(email)
if (success != true)
    print mailman.lastErrorText() + "\n";
    exit
end

# Close the connection with the server.  This closes the tunnel through ssh2.
success = mailman.CloseSmtpConnection()
if (success != true)
    print "Connection to SMTP server not closed cleanly." + "\n";
end

print "Mail Sent!" + "\n";

# 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()