(PureBasic) 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.

Chilkat PureBasic Module Download Chilkat PureBasic Module

IncludeFile "CkPrivateKey.pb"
IncludeFile "CkCert.pb"

Procedure ChilkatExample()

    cert.i = CkCert::ckCreate()
    If cert.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ; Load from the PFX file
    pfxFilename.s = "/Users/chilkat/testData/pfx/chilkat_ssl_pwd_is_test.pfx"
    pfxPassword.s = "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.i = CkCert::ckLoadPfxFile(cert,pfxFilename,pfxPassword)
    If success <> 1
        Debug CkCert::ckLastErrorText(cert)
        CkCert::ckDispose(cert)
        ProcedureReturn
    EndIf

    ; Get the private key...
    privKey.i
    privKey = CkCert::ckExportPrivateKey(cert)
    If CkCert::ckLastMethodSuccess(cert) = 0
        Debug CkCert::ckLastErrorText(cert)
        CkCert::ckDispose(cert)
        ProcedureReturn
    EndIf

    ; Export to various formats:

    password.s = "secret"
    path.s

    ; PKCS8 Encrypted DER
    path = "/Users/chilkat/testData/privkeys/chilkat_pkcs8_enc.der"
    success = CkPrivateKey::ckSavePkcs8EncryptedFile(privKey,password,path)
    If success <> 1
        Debug CkPrivateKey::ckLastErrorText(privKey)
        CkPrivateKey::ckDispose(privKey)

        CkCert::ckDispose(cert)
        ProcedureReturn
    EndIf

    ; PKCS8 Encrypted PEM
    path = "/Users/chilkat/testData/privkeys/chilkat_pkcs8_enc.pem"
    success = CkPrivateKey::ckSavePkcs8EncryptedPemFile(privKey,password,path)
    If success <> 1
        Debug CkPrivateKey::ckLastErrorText(privKey)
        CkPrivateKey::ckDispose(privKey)

        CkCert::ckDispose(cert)
        ProcedureReturn
    EndIf

    ; PKCS8 Unencrypted DER
    path = "/Users/chilkat/testData/privkeys/chilkat_pkcs8.der"
    success = CkPrivateKey::ckSavePkcs8File(privKey,path)
    If success <> 1
        Debug CkPrivateKey::ckLastErrorText(privKey)
        CkPrivateKey::ckDispose(privKey)

        CkCert::ckDispose(cert)
        ProcedureReturn
    EndIf

    ; PKCS8 Unencrypted PEM
    path = "/Users/chilkat/testData/privkeys/chilkat_pkcs8.pem"
    success = CkPrivateKey::ckSavePkcs8PemFile(privKey,path)
    If success <> 1
        Debug CkPrivateKey::ckLastErrorText(privKey)
        CkPrivateKey::ckDispose(privKey)

        CkCert::ckDispose(cert)
        ProcedureReturn
    EndIf

    ;  RSA DER (unencrypted)
    path = "/Users/chilkat/testData/privkeys/chilkat_rsa.der"
    success = CkPrivateKey::ckSavePkcs1File(privKey,path)
    If success <> 1
        Debug CkPrivateKey::ckLastErrorText(privKey)
        CkPrivateKey::ckDispose(privKey)

        CkCert::ckDispose(cert)
        ProcedureReturn
    EndIf

    ; RSA PEM (unencrypted)
    path = "/Users/chilkat/testData/privkeys/chilkat_rsa.pem"
    success = CkPrivateKey::ckSavePemFile(privKey,path)
    If success <> 1
        Debug CkPrivateKey::ckLastErrorText(privKey)
        CkPrivateKey::ckDispose(privKey)

        CkCert::ckDispose(cert)
        ProcedureReturn
    EndIf

    ; XML (unencrypted)
    path = "/Users/chilkat/testData/privkeys/chilkat.xml"
    success = CkPrivateKey::ckSaveXmlFile(privKey,path)
    If success <> 1
        Debug CkPrivateKey::ckLastErrorText(privKey)
        CkPrivateKey::ckDispose(privKey)

        CkCert::ckDispose(cert)
        ProcedureReturn
    EndIf

    CkPrivateKey::ckDispose(privKey)

    Debug "Private key exported to all formats."


    CkCert::ckDispose(cert)


    ProcedureReturn
EndProcedure