(Lianja) IMAP SSH Tunneling (Port Forwarding)

Demonstrates how to setup and use an SSH tunnel for IMAP.

Chilkat Lianja Extension Download Chilkat Lianja Extension

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

loImap = createobject("CkImap")

// 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).
lcSshHostname = "www.mysshserver.com"
lnSshPort = 22

// Connect to an SSH server and establish the SSH tunnel:
llSuccess = loImap.SshOpenTunnel(lcSshHostname,lnSshPort)
if (llSuccess <> .T.) then
    ? loImap.LastErrorText
    release loImap
    return
endif

// 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 IMAP server, it is
// for authenticating with the SSH server, which is separate.
llSuccess = loImap.SshAuthenticatePw("mySshLogin","mySshPassword")
if (llSuccess <> .T.) then
    ? loImap.LastErrorText
    release loImap
    return
endif

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

// Connect to an IMAP server via the SSH tunnel.
// Because the SSH tunnel has been previously setup,
// this does not establish a direct connection with the IMAP
// server.  It directs the SSH server to establish the connection.

// In this example, the IMAP server requires SSL/TLS.  The TLS connection
// will be enclosed within the SSH tunnel.
loImap.Ssl = .T.
loImap.Port = 993
llSuccess = loImap.Connect("imap.my-imap-server.com")
if (llSuccess <> .T.) then
    ? loImap.LastErrorText
    release loImap
    return
endif

// Authenticate with the IMAP server via the SSH tunnel.
llSuccess = loImap.Login("myLogin","myPassword")
if (llSuccess <> .T.) then
    ? loImap.LastErrorText
    release loImap
    return
endif

// Select an IMAP mailbox
llSuccess = loImap.SelectMailbox("Inbox")
if (llSuccess <> .T.) then
    ? loImap.LastErrorText
    release loImap
    return
endif

// How many messages in Inbox?
lnMsgCount = loImap.NumMessages
if (lnMsgCount = 0) then
    ? "No messages found."
    release loImap
    return
endif

lnUpperBound = 10
if (lnMsgCount < lnUpperBound) then
    lnUpperBound = lnMsgCount
endif

// Download up to the 1st 10 messages.

llBUid = .F.
for i = 1 to lnUpperBound

    loEmail = loImap.FetchSingle(i,llBUid)
    if (loImap.LastMethodSuccess = .F.) then
        ? loImap.LastErrorText
        release loImap
        return

    else
        ? loEmail.From
        ? loEmail.Subject
        ? "----"

        release loEmail
    endif

next

// Disconnect from the IMAP server.
// The SSH tunnel remains open.
llSuccess = loImap.Disconnect()
if (llSuccess <> .T.) then
    ? loImap.LastErrorText
    release loImap
    return
endif

// It is possible to re-use the existing SSH tunnel for the next connection:
llSuccess = loImap.Connect("imap.my-imap-server2.com")
if (llSuccess <> .T.) then
    ? loImap.LastErrorText
    release loImap
    return
endif

// Review the LastErrorText to see that the connection was made via the SSH tunnel:
? loImap.LastErrorText

llSuccess = loImap.Disconnect()
if (llSuccess <> .T.) then
    ? loImap.LastErrorText
    release loImap
    return
endif

// Finally, close the SSH tunnel.
llSuccess = loImap.SshCloseTunnel()
if (llSuccess <> .T.) then
    ? loImap.LastErrorText
    release loImap
    return
endif

? "IMAP SSH tunneling example completed."


release loImap