(VB.NET) Secure FTP with Client Certificate

Chilkat FTP2 provides the ability to use a client certificate with secure FTP (implicit or explicit SSL/TLS). This example demonstrates how to load a certificate from a .pfx and use it as the client-side SSL cert. Note: Client-side certificates are only needed in situations where the server demands one.

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

Dim ftp As New Chilkat.Ftp2

ftp.Hostname = "ftp.***.com"
ftp.Port = 21
ftp.Username = "test"
ftp.Password = "test"

' This example will use explict TLS/SSL.
' Establish an explicit secure channel after connection
' on the standard FTP port 21.
ftp.AuthTls = True

' The Ssl property is for establishing an implicit SSL connection
' on port 990.  Because this example uses explicit SSL, it 
' should remain False.
ftp.Ssl = False

' Load a certificate from a .pfx
' A PFX may contain several certs, including the certificates
' in a chain of authority.
Dim certStore As New Chilkat.CertStore
Dim password As String
password = "***"
' Load the certs from a PFX into an in-memory certificate store:
Dim success As Boolean = certStore.LoadPfxFile("chilkat.pfx",password)
If (success <> True) Then
    Debug.WriteLine(certStore.LastErrorText)
    Exit Sub
End If


' Find the exact cert we'll use:
Dim cert As Chilkat.Cert
cert = certStore.FindCertBySubject("Chilkat Software, Inc.")
If (certStore.LastMethodSuccess = False) Then
    Debug.WriteLine("Certificate not found!")
    Exit Sub
End If


' Use this certificate for our secure (SSL/TLS) connection:
success = ftp.SetSslClientCert(cert)


' Connect and login to the FTP server.  The connection is 
' made secure because of the AuthTls setting.
success = ftp.Connect()
If (success <> True) Then
    Debug.WriteLine(ftp.LastErrorText)
    Exit Sub
Else
    ' LastErrorText contains information even when
    ' successful. This allows you to visually verify
    ' that the secure connection actually occurred.
    Debug.WriteLine(ftp.LastErrorText)
End If


Debug.WriteLine("Secure FTP Channel Established!")

' Do whatever you're doing to do ...
' upload files, download files, etc...

' .....
' .....


success = ftp.Disconnect()