Export a Certificate's Private Key to Various Formats

Loads a digital certificate and private key from a PFX file (also known as PKCS#12) and exports the private key to various formats: (1) PKCS8 Encrypted, (2) PKCS8 Encrypted PEM, (3) PKCS8 unencrypted, (4) PKCS8 PEM unencrypted, (5) RSA DER unencrypted, (6) RSA PEM unencrypted, (7) XML.

Dim cert As New ChilkatCert

Dim success As Long

'  Load from the PFX file
Dim pfxFilename As String
pfxFilename = "/Users/chilkat/testData/pfx/chilkat_ssl_pwd_is_test.pfx"
Dim pfxPassword As String
pfxPassword = "test"

'  A PFX typically contains certificates in the chain of authentication.
'  The Chilkat cert object will choose the certificate w/
'  private key farthest from the root authority cert.
'  To access all the certificates in a PFX, use the
'  Chilkat certificate store object instead.
success = cert.LoadPfxFile(pfxFilename,pfxPassword)
If (success <> 1) Then
    Text1.Text = Text1.Text & cert.LastErrorText & vbCrLf
    Exit Sub
End If

'  Get the private key...
Dim privKey As PrivateKey
Set privKey = cert.ExportPrivateKey()
If (privKey Is Nothing ) Then
    Text1.Text = Text1.Text & cert.LastErrorText & vbCrLf
    Exit Sub
End If

'  Export to various formats:

Dim password As String
password = "secret"
Dim path As String

'  PKCS8 Encrypted DER
path = "/Users/chilkat/testData/privkeys/chilkat_pkcs8_enc.der"
success = privKey.SavePkcs8EncryptedFile(password,path)
If (success <> 1) Then
    Text1.Text = Text1.Text & privKey.LastErrorText & vbCrLf

    Exit Sub
End If

'  PKCS8 Encrypted PEM
path = "/Users/chilkat/testData/privkeys/chilkat_pkcs8_enc.pem"
success = privKey.SavePkcs8EncryptedPemFile(password,path)
If (success <> 1) Then
    Text1.Text = Text1.Text & privKey.LastErrorText & vbCrLf

    Exit Sub
End If

'  PKCS8 Unencrypted DER
path = "/Users/chilkat/testData/privkeys/chilkat_pkcs8.der"
success = privKey.SavePkcs8File(path)
If (success <> 1) Then
    Text1.Text = Text1.Text & privKey.LastErrorText & vbCrLf

    Exit Sub
End If

'  PKCS8 Unencrypted PEM
path = "/Users/chilkat/testData/privkeys/chilkat_pkcs8.pem"
success = privKey.SavePkcs8PemFile(path)
If (success <> 1) Then
    Text1.Text = Text1.Text & privKey.LastErrorText & vbCrLf

    Exit Sub
End If

'   RSA DER (unencrypted)
path = "/Users/chilkat/testData/privkeys/chilkat_rsa.der"
success = privKey.SaveRsaDerFile(path)
If (success <> 1) Then
    Text1.Text = Text1.Text & privKey.LastErrorText & vbCrLf

    Exit Sub
End If

'  RSA PEM (unencrypted)
path = "/Users/chilkat/testData/privkeys/chilkat_rsa.pem"
success = privKey.SaveRsaPemFile(path)
If (success <> 1) Then
    Text1.Text = Text1.Text & privKey.LastErrorText & vbCrLf

    Exit Sub
End If

'  XML (unencrypted)
path = "/Users/chilkat/testData/privkeys/chilkat.xml"
success = privKey.SaveXmlFile(path)
If (success <> 1) Then
    Text1.Text = Text1.Text & privKey.LastErrorText & vbCrLf

    Exit Sub
End If

Text1.Text = Text1.Text & "Private key exported to all formats." & vbCrLf