(Swift 2) 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 Downloads for the Swift Programming Language MAC OS X (Cocoa) Objective-C/Swift Libs iOS Objective-C/Swift Libs

func chilkatTest() {
    // 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.
    let mailman = CkoMailMan()

    // 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).
    var sshHostname: String? = "www.my-ssh-server.com"
    var sshPort: Int = 22

    // Connect to an SSH server and establish the SSH tunnel:
    var success: Bool = mailman.SshOpenTunnel(sshHostname, sshPort: sshPort)
    if success != true {
        print("\(mailman.LastErrorText)")
        return
    }

    // 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", sshPassword: "ssh_password")
    if success != true {
        print("\(mailman.LastErrorText)")
        return
    }

    // 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 != true {
        print("\(mailman.LastErrorText)")
        return
    }

    // 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.
    print("\(mailman.LastErrorText)")

    // How many messages are in the POP3 inbox?
    var numToDownload: Int = mailman.GetMailboxCount().intValue
    if numToDownload > 5 {
        numToDownload = 5
    }

    if numToDownload == 0 {
        return
    }

    // Download a max of 5 messages
    var i: Int
    var email: CkoEmail?
    for i = 1; i <= numToDownload; i++ {
        email = mailman.FetchByMsgnum(i)
        if mailman.LastMethodSuccess == false {
            print("\(mailman.LastErrorText)")
            return
        }

        print("\(email!.From)")
        print("\(email!.Subject)")
        print("----")
        email = nil
    }

    // Close the connection with the POP3 server, leaving the SSH tunnel open for subsequent POP3 connections.
    success = mailman.Pop3EndSession()
    if success != true {
        print("\(mailman.LastErrorText)")
        return
    }

    // 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 != true {
        print("\(mailman.LastErrorText)")
        return
    }

    // Review the LastErrorText to see that the connection was made via the SSH tunnel:
    print("\(mailman.LastErrorText)")

    success = mailman.Pop3EndSession()
    if success != true {
        print("\(mailman.LastErrorText)")
        return
    }

    // Close the SSH tunnel.
    success = mailman.SshCloseTunnel()
    if success != true {
        print("\(mailman.LastErrorText)")
        return
    }


}