(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.

Note: This example requires Chilkat v11.0.0 or greater.

Chilkat PureBasic Module Download Chilkat PureBasic Module

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

Procedure ChilkatExample()

    success.i = 0

    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 = CkCert::ckLoadPfxFile(cert,pfxFilename,pfxPassword)
    If success = 0
        Debug CkCert::ckLastErrorText(cert)
        CkCert::ckDispose(cert)
        ProcedureReturn
    EndIf

    ; Get the private key...
    privKey.i = CkPrivateKey::ckCreate()
    If privKey.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkCert::ckGetPrivateKey(cert,privKey)
    If success = 0
        Debug CkCert::ckLastErrorText(cert)
        CkCert::ckDispose(cert)
        CkPrivateKey::ckDispose(privKey)
        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 = 0
        Debug CkPrivateKey::ckLastErrorText(privKey)
        CkCert::ckDispose(cert)
        CkPrivateKey::ckDispose(privKey)
        ProcedureReturn
    EndIf

    ; PKCS8 Encrypted PEM
    path = "/Users/chilkat/testData/privkeys/chilkat_pkcs8_enc.pem"
    success = CkPrivateKey::ckSavePkcs8EncryptedPemFile(privKey,password,path)
    If success = 0
        Debug CkPrivateKey::ckLastErrorText(privKey)
        CkCert::ckDispose(cert)
        CkPrivateKey::ckDispose(privKey)
        ProcedureReturn
    EndIf

    ; PKCS8 Unencrypted DER
    path = "/Users/chilkat/testData/privkeys/chilkat_pkcs8.der"
    success = CkPrivateKey::ckSavePkcs8File(privKey,path)
    If success = 0
        Debug CkPrivateKey::ckLastErrorText(privKey)
        CkCert::ckDispose(cert)
        CkPrivateKey::ckDispose(privKey)
        ProcedureReturn
    EndIf

    ; PKCS8 Unencrypted PEM
    path = "/Users/chilkat/testData/privkeys/chilkat_pkcs8.pem"
    success = CkPrivateKey::ckSavePkcs8PemFile(privKey,path)
    If success = 0
        Debug CkPrivateKey::ckLastErrorText(privKey)
        CkCert::ckDispose(cert)
        CkPrivateKey::ckDispose(privKey)
        ProcedureReturn
    EndIf

    ;  RSA DER (unencrypted)
    path = "/Users/chilkat/testData/privkeys/chilkat_rsa.der"
    success = CkPrivateKey::ckSavePkcs1File(privKey,path)
    If success = 0
        Debug CkPrivateKey::ckLastErrorText(privKey)
        CkCert::ckDispose(cert)
        CkPrivateKey::ckDispose(privKey)
        ProcedureReturn
    EndIf

    ; RSA PEM (unencrypted)
    path = "/Users/chilkat/testData/privkeys/chilkat_rsa.pem"
    success = CkPrivateKey::ckSavePemFile(privKey,path)
    If success = 0
        Debug CkPrivateKey::ckLastErrorText(privKey)
        CkCert::ckDispose(cert)
        CkPrivateKey::ckDispose(privKey)
        ProcedureReturn
    EndIf

    ; XML (unencrypted)
    path = "/Users/chilkat/testData/privkeys/chilkat.xml"
    success = CkPrivateKey::ckSaveXmlFile(privKey,path)
    If success = 0
        Debug CkPrivateKey::ckLastErrorText(privKey)
        CkCert::ckDispose(cert)
        CkPrivateKey::ckDispose(privKey)
        ProcedureReturn
    EndIf

    Debug "Private key exported to various formats."


    CkCert::ckDispose(cert)
    CkPrivateKey::ckDispose(privKey)


    ProcedureReturn
EndProcedure