(SQL Server) 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.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

-- Important: See this note about string length limitations for strings returned by sp_OAMethod calls.
--
CREATE PROCEDURE ChilkatSample
AS
BEGIN
    DECLARE @hr int
    -- Important: Do not use nvarchar(max).  See the warning about using nvarchar(max).
    DECLARE @sTmp0 nvarchar(4000)
    -- 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.
    DECLARE @mailman int
    -- Use "Chilkat_9_5_0.MailMan" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.MailMan', @mailman OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    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).
    DECLARE @sshHostname nvarchar(4000)
    SELECT @sshHostname = 'sftp.example.com'
    DECLARE @sshPort int
    SELECT @sshPort = 22

    DECLARE @success int
    EXEC sp_OAMethod @mailman, 'SshOpenTunnel', @success OUT, @sshHostname, @sshPort
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @mailman, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @mailman
        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.
    EXEC sp_OAMethod @mailman, 'SshAuthenticatePw', @success OUT, 'sshLogin', 'sshPassword'
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @mailman, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @mailman
        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.
    EXEC sp_OASetProperty @mailman, 'SmtpHost', 'smtp.my-smtp-server.com'

    -- Set the SMTP login/password (if required)
    EXEC sp_OASetProperty @mailman, 'SmtpUsername', 'smtpLogin'
    EXEC sp_OASetProperty @mailman, 'SmtpPassword', 'smtpPassword'

    -- Create a new email object
    DECLARE @email int
    -- Use "Chilkat_9_5_0.Email" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.Email', @email OUT

    EXEC sp_OASetProperty @email, 'Subject', 'This is a test'
    EXEC sp_OASetProperty @email, 'Body', 'This is a test'
    EXEC sp_OASetProperty @email, 'From', 'Chilkat Support <support@chilkatsoft.com>'
    EXEC sp_OAMethod @email, 'AddTo', @success OUT, 'Chilkat Admin', 'admin@chilkatsoft.com'

    -- 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.  
    EXEC sp_OAMethod @mailman, 'SendEmail', @success OUT, @email
    IF @success <> 1
      BEGIN
        EXEC sp_OAGetProperty @mailman, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @mailman
        EXEC @hr = sp_OADestroy @email
        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.
    EXEC sp_OAGetProperty @mailman, 'LastErrorText', @sTmp0 OUT
    PRINT @sTmp0

    -- 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.  


    PRINT 'Mail Sent!'

    EXEC @hr = sp_OADestroy @mailman
    EXEC @hr = sp_OADestroy @email


END
GO