DataFlex

SMTP SSH Tunneling (Port Forwarding)

Demonstrates how to setup an SSH tunnel for SMTP. This example connects to an SMTP sever via an SSH tunnel and sends an email. DataFlex

Use ChilkatAx-win32.pkg

Procedure Test
    Boolean iSuccess
    Handle hoMailman
    String sSshHostname
    Integer iSshPort
    Variant vEmail
    Handle hoEmail
    String sTemp1

    Move False To iSuccess

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

    // The mailman object is used for sending (SMTP) and receiving (POP3) email.
    Get Create (RefClass(cComChilkatMailMan)) To hoMailman
    If (Not(IsComObjectCreated(hoMailman))) Begin
        Send CreateComObject of hoMailman
    End

    // Connect to an SSH server and establish the SSH tunnel:

    // The SSH hostname may be a hostname or an 
    // IP address, such as "192.168.1.108".
    // The port is typically 22 (the standard port for SSH).
    Move "sftp.example.com" To sSshHostname
    Move 22 To iSshPort

    Get ComSshOpenTunnel Of hoMailman sSshHostname iSshPort To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoMailman To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Authenticate with the SSH server via a login/password
    // or with a public key.
    // This example demonstrates SSH password authentication.
    // Note: This is not authenticating with the SMTP server, it is
    // for authenticating with the SSH server, which is separate.
    Get ComSshAuthenticatePw Of hoMailman "sshLogin" "sshPassword" To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoMailman To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // OK, the SSH tunnel is setup.  The mailman may
    // be used exactly the same as usual, except all communications
    // are now sent through the SSH tunnel.

    // Set the SMTP server.
    Set ComSmtpHost Of hoMailman To "smtp.my-smtp-server.com"

    // Set the SMTP login/password (if required)
    Set ComSmtpUsername Of hoMailman To "smtpLogin"
    Set ComSmtpPassword Of hoMailman To "smtpPassword"

    // Create a new email object
    Get Create (RefClass(cComChilkatEmail)) To hoEmail
    If (Not(IsComObjectCreated(hoEmail))) Begin
        Send CreateComObject of hoEmail
    End

    Set ComSubject Of hoEmail To "This is a test"
    Set ComBody Of hoEmail To "This is a test"
    Set ComFrom Of hoEmail To "Chilkat Support <support@chilkatsoft.com>"
    Get ComAddTo Of hoEmail "Chilkat Admin" "admin@chilkatsoft.com" To iSuccess

    // The call to SendEmail automatically connects to the SMTP
    // server via the SSH tunnel (if not already connected).
    // Because the SSH tunnel has been previously setup,
    // this does not establish a direct connection with the SMTP
    // server.  It directs the SSH server to establish the connection.

    // After SendEmail completes, the connection (i.e. session) remains
    // open so that subsequent SendEmail calls may use the
    // same SSH tunnel.  
    Get pvComObject of hoEmail to vEmail
    Get ComSendEmail Of hoMailman vEmail To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoMailman To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // If you're curious, have a look at LastErrorText after
    // a successful send.  You'll see detailed information that 
    // confirms the SSH tunneling.
    Get ComLastErrorText Of hoMailman To sTemp1
    Showln sTemp1

    // Note: Some SMTP servers do not actually send the email until 
    // the connection is closed.  In these cases, it is necessary to
    // call CloseSmtpConnection for the mail to be  sent.  
    // Most SMTP servers send the email immediately, and it is 
    // not required to close the connection.  

    Showln "Mail Sent!"


End_Procedure