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Xojo Plugin

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.

Chilkat Xojo Plugin Downloads

Xojo Plugin
Dim success As Boolean
success = False

// 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.
Dim mailman As New Chilkat.MailMan

// 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).
Dim sshHostname As String
sshHostname = "sftp.example.com"
Dim sshPort As Int32
sshPort = 22

// Connect to an SSH server and establish the SSH tunnel:
success = mailman.SshOpenTunnel(sshHostname,sshPort)
If (success = False) Then
    System.DebugLog(mailman.LastErrorText)
    Return
End If

// 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.
success = mailman.SshAuthenticatePw("ssh_login","ssh_password")
If (success = False) Then
    System.DebugLog(mailman.LastErrorText)
    Return
End If

// 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
mailman.MailHost = "mail.my-pop3-server.com"

// Set the POP3 settings for your POP3 server:
mailman.PopUsername = "pop3_login"
mailman.PopPassword = "pop3_password"
mailman.MailPort = 995
mailman.PopSsl = True

// Connect to the POP3 server through the already-established SSH tunnel:
success = mailman.Pop3BeginSession()
If (success = False) Then
    System.DebugLog(mailman.LastErrorText)
    Return
End If

// 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.
System.DebugLog(mailman.LastErrorText)

// How many messages are in the POP3 inbox?
Dim numToDownload As Int32
numToDownload = mailman.GetMailboxCount()
If (numToDownload > 5) Then
    numToDownload = 5
End If

If (numToDownload = 0) Then
    System.DebugLog("No messages in the POP3 inbox.")
    Return
End If

// Download a max of 5 messages
Dim i As Int32
Dim email As New Chilkat.Email
For i = 1 To numToDownload
    success = mailman.FetchOne(False,0,i,email)
    If (success = False) Then
        System.DebugLog(mailman.LastErrorText)
        Return
    End If

    System.DebugLog(email.From)
    System.DebugLog(email.Subject)
    System.DebugLog("----")
Next

// Close the connection with the POP3 server, leaving the SSH tunnel open for subsequent POP3 connections.
success = mailman.Pop3EndSession()
If (success = False) Then
    System.DebugLog(mailman.LastErrorText)
    Return
End If

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

// Set the POP3 settings for your POP3 server:
mailman.PopUsername = "pop3_login2"
mailman.PopPassword = "pop3_password2"
mailman.MailPort = 110
mailman.PopSsl = False

success = mailman.Pop3BeginSession()
If (success = False) Then
    System.DebugLog(mailman.LastErrorText)
    Return
End If

// Review the LastErrorText to see that the connection was made via the SSH tunnel:
System.DebugLog(mailman.LastErrorText)

success = mailman.Pop3EndSession()
If (success = False) Then
    System.DebugLog(mailman.LastErrorText)
    Return
End If

// Close the SSH tunnel.
success = mailman.SshCloseTunnel()
If (success = False) Then
    System.DebugLog(mailman.LastErrorText)
    Return
End If