Visual FoxPro

Working with PEM Encrypted Private Keys

See more PEM Examples

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

LOCAL lnSuccess
LOCAL loPem
LOCAL lcPemPassword
LOCAL loFac
LOCAL lcPemText
LOCAL i
LOCAL lnNumPrivateKeys
LOCAL loPrivKey

lnSuccess = 0

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

lnSuccess = 0

loPem = CreateObject('Chilkat.Pem')

lcPemPassword = "secret"

* To load a PEM file containing encrypted private keys, simply
* provide the password.
lnSuccess = loPem.LoadPemFile("/Users/chilkat/testData/pem/pemContainingEncryptedPrivateKeys.pem",lcPemPassword)
IF (lnSuccess = 0) THEN
    ? loPem.LastErrorText
    RELEASE loPem
    CANCEL
ENDIF

loFac = CreateObject('Chilkat.FileAccess')
lcPemText = loFac.ReadEntireTextFile("/Users/chilkat/testData/pem/pemContainingEncryptedPrivateKeys.pem",lcPemPassword)

* To load a PEM from a string, call LoadPem instead of LoadPemFile:
lnSuccess = loPem.LoadPem(lcPemText)
IF (lnSuccess = 0) THEN
    ? loPem.LastErrorText
    RELEASE loPem
    RELEASE loFac
    CANCEL
ENDIF

* 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:

lnNumPrivateKeys = loPem.NumPrivateKeys
IF (lnNumPrivateKeys = 0) THEN
    ? ("Error: Expected the PEM to contain private keys.")
    RELEASE loPem
    RELEASE loFac
    CANCEL
ENDIF

loPrivKey = CreateObject('Chilkat.PrivateKey')
FOR i = 1 TO lnNumPrivateKeys
    loPem.PrivateKeyAt(i - 1,loPrivKey)
    ? STR(i) + ": " + STR(loPrivKey.BitLength) + " bits"
NEXT

RELEASE loPem
RELEASE loFac
RELEASE loPrivKey