Visual Basic 6.0

Working with PEM Encrypted Private Keys

See more PEM Examples

Demonstrates how to load and save PEM encrypted private keys. Visual Basic 6.0

Dim success As Long
success = 0

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

success = 0

Dim pem As New ChilkatPem

Dim pemPassword As String
pemPassword = "secret"

' To load a PEM file containing encrypted private keys, simply
' provide the password.
success = pem.LoadPemFile("/Users/chilkat/testData/pem/pemContainingEncryptedPrivateKeys.pem",pemPassword)
If (success = 0) Then
    Debug.Print pem.LastErrorText
    Exit Sub
End If

Dim fac As New CkFileAccess
Dim pemText As String
pemText = fac.ReadEntireTextFile("/Users/chilkat/testData/pem/pemContainingEncryptedPrivateKeys.pem",pemPassword)

' To load a PEM from a string, call LoadPem instead of LoadPemFile:
success = pem.LoadPem(pemText)
If (success = 0) Then
    Debug.Print pem.LastErrorText
    Exit Sub
End If

' A few notes:
' The PEM may contain both private keys and certificates (or anything else).
' The password is utilized for whatever content in the PEM is encrypted.  
' It is OK to have both encrypted and non-encrypted content within a given PEM.

' PEM private keys can be encrypted in different formats.  The LoadPem and LoadPemFile
' methods automatically handle the different formats.
' One format is PKCS8 and is indicated by this delimiter within the PEM:

' -----BEGIN ENCRYPTED PRIVATE KEY-----
' MIICoTAbBgkqhkiG9w0BBQMwDgQIfdD0zv24lgkCAggABIICgE0PdHJmRbNs6cBX
' ...

' Another format, we'll call "passphrase" looks like this in the PEM:
' -----BEGIN RSA PRIVATE KEY-----
' Proc-Type: 4,ENCRYPTED
' DEK-Info: DES-EDE3-CBC,A4215544D11C5D0C
' 
' paqy9XRexcSjurHfG0xhCaUD0HrvIdhuC0CbRxxxeMlkLaV6+uT80rBxt2AaibWG
' ...

' Show the bit length of each private key:
Dim i As Long
Dim numPrivateKeys As Long
numPrivateKeys = pem.NumPrivateKeys
If (numPrivateKeys = 0) Then
    Debug.Print (("Error: Expected the PEM to contain private keys."))
    Exit Sub
End If

Dim privKey As New PrivateKey
For i = 1 To numPrivateKeys
    success = pem.PrivateKeyAt(i - 1,privKey)
    Debug.Print i & ": " & privKey.BitLength & " bits"
Next