(PureBasic) IMAP over Multiple Hop SSH

Demonstrates how to read IMAP email (using TCP or TLS) tunneled through mulitple-hop SSH. The scheme looks like this:

Application => ServerSSH1 => ServerSSH2 => IMAPServer

The ConnectThroughSsh and UseSsh methods are added in Chilkat version 9.5.0.55 to accomplish this task.

Chilkat PureBasic Module Download Chilkat PureBasic Module

IncludeFile "CkSsh.pb"
IncludeFile "CkImap.pb"

Procedure ChilkatExample()

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

    ssh1.i = CkSsh::ckCreate()
    If ssh1.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ; Connect directly to the 1st SSH server.
    success.i = CkSsh::ckConnect(ssh1,"serverssh1.com",22)
    If success <> 1
        Debug CkSsh::ckLastErrorText(ssh1)
        CkSsh::ckDispose(ssh1)
        ProcedureReturn
    EndIf

    ; Authenticate using login/password:
    success = CkSsh::ckAuthenticatePw(ssh1,"ssh1Login","ssh1Password")
    If success <> 1
        Debug CkSsh::ckLastErrorText(ssh1)
        CkSsh::ckDispose(ssh1)
        ProcedureReturn
    EndIf

    ; Connect through the 1st SSH connection to reach a 2nd SSH server.
    ; Note: Any number of SSH connections may be simultaneously tunneled through a single
    ; existing SSH connection.
    ssh2.i = CkSsh::ckCreate()
    If ssh2.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkSsh::ckConnectThroughSsh(ssh2,ssh1,"serverssh2.com",22)
    If success <> 1
        Debug CkSsh::ckLastErrorText(ssh2)
        CkSsh::ckDispose(ssh1)
        CkSsh::ckDispose(ssh2)
        ProcedureReturn
    EndIf

    ; Authenticate with ssh2...
    success = CkSsh::ckAuthenticatePw(ssh2,"ssh2Login","ssh2Password")
    If success <> 1
        Debug CkSsh::ckLastErrorText(ssh2)
        CkSsh::ckDispose(ssh1)
        CkSsh::ckDispose(ssh2)
        ProcedureReturn
    EndIf

    imap.i = CkImap::ckCreate()
    If imap.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ; Tell the IMAP object to connect to the IMAP server though the ssh2 tunnel (which itself is routed through ssh1).
    ; The connection looks like this:  Application => ServerSSH1 => ServerSSH2 => IMAPServer
    success = CkImap::ckUseSsh(imap,ssh2)
    If success <> 1
        Debug CkImap::ckLastErrorText(imap)
        CkSsh::ckDispose(ssh1)
        CkSsh::ckDispose(ssh2)
        CkImap::ckDispose(imap)
        ProcedureReturn
    EndIf

    CkImap::setCkSsl(imap, 1)
    CkImap::setCkPort(imap, 993)

    ; Connect to an IMAP server (through the multi-hop SSH tunnel)
    success = CkImap::ckConnect(imap,"imap.someimapserver.com")
    If success <> 1
        Debug CkImap::ckLastErrorText(imap)
        CkSsh::ckDispose(ssh1)
        CkSsh::ckDispose(ssh2)
        CkImap::ckDispose(imap)
        ProcedureReturn
    EndIf

    ; Login
    success = CkImap::ckLogin(imap,"myLogin","myPassword")
    If success <> 1
        Debug CkImap::ckLastErrorText(imap)
        CkSsh::ckDispose(ssh1)
        CkSsh::ckDispose(ssh2)
        CkImap::ckDispose(imap)
        ProcedureReturn
    EndIf

    ; Do whatever needs to be done...  for example,

    ; Create the new email folder (sub-mailbox) on the IMAP server.
    ; If no folder path is provided, the new folder is a sub-mailbox of Inbox.
    success = CkImap::ckCreateMailbox(imap,"newFolder")
    If success <> 1
        Debug CkImap::ckLastErrorText(imap)
        CkSsh::ckDispose(ssh1)
        CkSsh::ckDispose(ssh2)
        CkImap::ckDispose(imap)
        ProcedureReturn
    EndIf

    Debug "Success."

    ; Close the connection with the IMAP server.  (This closes the tunnel through ssh2)
    ; The connection with ssh2 is still alive, and may be used for more connections.
    success = CkImap::ckDisconnect(imap)

    ; Close the connection with ssh2.  (This closes the the tunnel through ssh1.)
    ; The connection with ssh1 is still alive, and may be used for more connections.
    CkSsh::ckDisconnect(ssh2)

    CkSsh::ckDisconnect(ssh1)


    CkSsh::ckDispose(ssh1)
    CkSsh::ckDispose(ssh2)
    CkImap::ckDispose(imap)


    ProcedureReturn
EndProcedure