(SQL Server) POP3 SSH Tunneling (Port Forwarding)

Demonstrates how to connect to a POP3 server through an SSH tunnel. Reads a POP3 mailbox and display the FROM and SUBJECT header fields of each email.

Note: This example requires Chilkat v11.0.0 or greater.

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)
    DECLARE @success int
    SELECT @success = 0

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

    -- The mailman object is used for receiving (POP3) 
    -- and sending (SMTP) email.
    DECLARE @mailman int
    EXEC @hr = sp_OACreate 'Chilkat.MailMan', @mailman OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    -- 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

    -- Connect to an SSH server and establish the SSH tunnel:
    EXEC sp_OAMethod @mailman, 'SshOpenTunnel', @success OUT, @sshHostname, @sshPort
    IF @success = 0
      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 POP3 server, it is
    -- for authenticating with the SSH server, which is separate.
    EXEC sp_OAMethod @mailman, 'SshAuthenticatePw', @success OUT, 'ssh_login', 'ssh_password'
    IF @success = 0
      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.

    -- The SSH tunnel may be kept open for any number of 
    -- POP3 connections.  

    -- Set the POP3 server's hostname
    EXEC sp_OASetProperty @mailman, 'MailHost', 'mail.my-pop3-server.com'

    -- Set the POP3 settings for your POP3 server:
    EXEC sp_OASetProperty @mailman, 'PopUsername', 'pop3_login'
    EXEC sp_OASetProperty @mailman, 'PopPassword', 'pop3_password'
    EXEC sp_OASetProperty @mailman, 'MailPort', 995
    EXEC sp_OASetProperty @mailman, 'PopSsl', 1

    -- Connect to the POP3 server through the already-established SSH tunnel:
    EXEC sp_OAMethod @mailman, 'Pop3BeginSession', @success OUT
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @mailman, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @mailman
        RETURN
      END

    -- A visual inspection of the LastErrorText after
    -- a successful POP3 connection will confirm the SSH tunneling.
    -- Note: If the POP3 connection uses SSL/TLS, then the SSL/TLS 
    -- secure channel will be wrapped within the SSH tunnel.
    EXEC sp_OAGetProperty @mailman, 'LastErrorText', @sTmp0 OUT
    PRINT @sTmp0

    -- How many messages are in the POP3 inbox?
    DECLARE @numToDownload int
    EXEC sp_OAMethod @mailman, 'GetMailboxCount', @numToDownload OUT
    IF @numToDownload > 5
      BEGIN
        SELECT @numToDownload = 5
      END
    IF @numToDownload = 0
      BEGIN

        PRINT 'No messages in the POP3 inbox.'
        EXEC @hr = sp_OADestroy @mailman
        RETURN
      END

    -- Download a max of 5 messages
    DECLARE @i int

    DECLARE @email int
    EXEC @hr = sp_OACreate 'Chilkat.Email', @email OUT

    SELECT @i = 1
    WHILE @i <= @numToDownload
      BEGIN
        EXEC sp_OAMethod @mailman, 'FetchOne', @success OUT, 0, 0, @i, @email
        IF @success = 0
          BEGIN
            EXEC sp_OAGetProperty @mailman, 'LastErrorText', @sTmp0 OUT
            PRINT @sTmp0
            EXEC @hr = sp_OADestroy @mailman
            EXEC @hr = sp_OADestroy @email
            RETURN
          END

        EXEC sp_OAGetProperty @email, 'From', @sTmp0 OUT
        PRINT @sTmp0
        EXEC sp_OAGetProperty @email, 'Subject', @sTmp0 OUT
        PRINT @sTmp0

        PRINT '----'
        SELECT @i = @i + 1
      END

    -- Close the connection with the POP3 server, leaving the SSH tunnel open for subsequent POP3 connections.
    EXEC sp_OAMethod @mailman, 'Pop3EndSession', @success OUT
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @mailman, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @mailman
        EXEC @hr = sp_OADestroy @email
        RETURN
      END

    -- Try connecting to a different POP3 server through the same aleady setup SSH tunnel:
    -- Set the POP3 server's hostname
    EXEC sp_OASetProperty @mailman, 'MailHost', 'mail.my-pop3-server2.com'

    -- Set the POP3 settings for your POP3 server:
    EXEC sp_OASetProperty @mailman, 'PopUsername', 'pop3_login2'
    EXEC sp_OASetProperty @mailman, 'PopPassword', 'pop3_password2'
    EXEC sp_OASetProperty @mailman, 'MailPort', 110
    EXEC sp_OASetProperty @mailman, 'PopSsl', 0

    EXEC sp_OAMethod @mailman, 'Pop3BeginSession', @success OUT
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @mailman, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @mailman
        EXEC @hr = sp_OADestroy @email
        RETURN
      END

    -- Review the LastErrorText to see that the connection was made via the SSH tunnel:
    EXEC sp_OAGetProperty @mailman, 'LastErrorText', @sTmp0 OUT
    PRINT @sTmp0

    EXEC sp_OAMethod @mailman, 'Pop3EndSession', @success OUT
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @mailman, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @mailman
        EXEC @hr = sp_OADestroy @email
        RETURN
      END

    -- Close the SSH tunnel.
    EXEC sp_OAMethod @mailman, 'SshCloseTunnel', @success OUT
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @mailman, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @mailman
        EXEC @hr = sp_OADestroy @email
        RETURN
      END

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


END
GO