(Excel) Working with PEM Encrypted Private Keys

Demonstrates how to load and save PEM encrypted private keys.

Download Excel Class Modules Chilkat Excel Class Modules

' Starting in v9.5.0.49, all Chilkat classes can be unlocked at once at the beginning of a program
' by calling UnlockBundle.  It requires a Bundle unlock code.
Dim chilkatGlob As Chilkat.CkGlobal
Set chilkatGlob = Chilkat.NewCkGlobal

success = chilkatGlob.UnlockBundle("Anything for 30-day trial.")
If (success <> True) Then
    Debug.Print chilkatGlob.LastErrorText
    Exit Sub
End If

Dim pem As Chilkat.Pem
Set pem = Chilkat.NewPem


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 <> True) Then
    Debug.Print pem.LastErrorText
    Exit Sub
End If

Dim fac As Chilkat.FileAccess
Set fac = Chilkat.NewFileAccess

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 <> True) 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:


numPrivateKeys = pem.NumPrivateKeys
If (numPrivateKeys = 0) Then
    Debug.Print (("Error: Expected the PEM to contain private keys."))
    Exit Sub
End If

For i = 1 To numPrivateKeys

    Set privKey = pem.GetPrivateKey(i - 1)
    Debug.Print i; ": "; privKey.BitLength; " bits"

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