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DataFlex

Encrypt File using X.509 Certificate using AES in CBC Mode

See more Encryption Examples

Demonstrates how to encrypt a file using an X.509 Certificate's public key, where the underlying bulk encryption algorithm is 128-bit AES in CBC mode. (The underlying bulk encryption algorithm can be specified to be other algorithms/strengths.)

Chilkat DataFlex Downloads

DataFlex
Use ChilkatAx-win32.pkg

Procedure Test
    Boolean iSuccess
    Handle hoCrypt
    Variant vCert
    Handle hoCert
    String sTemp1

    Move False To iSuccess

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

    Get Create (RefClass(cComChilkatCrypt2)) To hoCrypt
    If (Not(IsComObjectCreated(hoCrypt))) Begin
        Send CreateComObject of hoCrypt
    End

    // Use public-key cryptography for encryption.
    Set ComCryptAlgorithm Of hoCrypt To "pki"

    // Get an X.509 certificate to use for encrypting.
    // Note: Chilkat provides many different ways of loading a certificate, from many different formats,
    // or if on Windows, from the installed certificates on the system.
    // This example simply loads a certificate from a file.
    // Also, for encryption, only the public key is needed.  Digital certificates embed the public key
    // within the X.509 format itself.  Therefore, if you have a certificate, you also have the public key.
    Get Create (RefClass(cComChilkatCert)) To hoCert
    If (Not(IsComObjectCreated(hoCert))) Begin
        Send CreateComObject of hoCert
    End
    Get ComLoadFromFile Of hoCert "qa_data/certs/testCert.cer" To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoCert To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Get pvComObject of hoCert to vCert
    Get ComSetEncryptCert Of hoCrypt vCert To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoCrypt To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Indicate the underlying bulk encryption algorithm to be used:
    Set ComPkcs7CryptAlg Of hoCrypt To "aes"
    Set ComKeyLength Of hoCrypt To 128

    // Note: When doing public-key encryption the underlying bulk symmetric cipher mode will always be CBC. (at least with Chilkat...)

    // There's one last option that could be set.  If is the RSA encryption encryption/padding scheme. 
    // By default, RSAES_PKCS1-V1_5 is used.  If desired, the OaepPadding property could be set to True to
    // use RSAES_OAEP.  (We'll leave it set at the default value of False)
    Set ComOaepPadding Of hoCrypt To False

    // Everything is specified.  Now just encrypt...
    // The output is PKCS7 in binary DER format.
    Get ComCkEncryptFile Of hoCrypt "qa_data/hamlet.xml" "qa_output/hamlet.p7" To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoCrypt To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Showln "Finished."


End_Procedure