(DataFlex) Example for both AES-128 and ChaCha20 to Encrypt Binary Data

Demonstrates the use of the new EncryptBd and DecryptBd methods introduced in Chilkat v9.5.0.67 to encrypt/decrypt binary bytes.

Note: This example requires Chilkat v9.5.0.67 or greater.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

Use ChilkatAx-9.5.0-win32.pkg

Procedure Test
    Variant vJpgBytes
    Handle hoJpgBytes
    Boolean iSuccess
    Handle hoCrypt
    String sIvHex
    String sKeyHex
    String sTemp1

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

    // Load a small JPG file to be encrypted/decrypted.
    Get Create (RefClass(cComChilkatBinData)) To hoJpgBytes
    If (Not(IsComObjectCreated(hoJpgBytes))) Begin
        Send CreateComObject of hoJpgBytes
    End
    Get ComLoadFile Of hoJpgBytes "qa_data/jpg/starfish.jpg" To iSuccess
    If (iSuccess <> True) Begin
        Showln "Failed to load JPG file."
        Procedure_Return
    End

    // Show the unencrypted JPG bytes in Base64 format.
    // (The "base64_mime" encoding was added in Chilkat v9.5.0.67.
    // The "base64" encoding emits a single line of base64, whereas
    // "base64_mime" will emit multi-line base64 as it would appear
    // in MIME.)
    Get ComGetEncoded Of hoJpgBytes "base64_mime" To sTemp1
    Showln sTemp1

    // Sample base64_mime JPG data:

    // 	/9j/4AAQSkZJRgABAgEASABIAAD/7Q18UGhvdG9zaG9wIDMuMAA4QklNA+0AAAAAABAASAAAAAEA
    // 	AQBIAAAAAQABOEJJTQPzAAAAAAAIAAAAAAAAAAE4QklNBAoAAAAAAAEAADhCSU0nEAAAAAAACgAB
    // 	AAAAAAAAAAI4QklNA/UAAAAAAEgAL2ZmAAEAbGZmAAYAAAAAAAEAL2ZmAAEAoZmaAAYAAAAAAAEA
    // 	MgAAAAEAWgAAAAYAAAAAAAEANQAAAAEALQAAAAYAAAAAAAE4QklNBBQAAAAAAAQAAAABOEJJTQQM
    // 	...

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

    // Specify the encryption to be used.
    // First we'll do AES-128 CBC
    Set ComCryptAlgorithm Of hoCrypt To "aes"
    Set ComCipherMode Of hoCrypt To "cbc"
    Set ComKeyLength Of hoCrypt To 128

    Move "000102030405060708090A0B0C0D0E0F" To sIvHex
    Send ComSetEncodedIV To hoCrypt sIvHex "hex"

    Move "000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F" To sKeyHex
    Send ComSetEncodedKey To hoCrypt sKeyHex "hex"

    // Do the in-place 128-bit AES CBC encryption.
    // The contents of jpgBytes are replaced with the encrypted bytes.
    Get pvComObject of hoJpgBytes to vJpgBytes
    Get ComEncryptBd Of hoCrypt vJpgBytes To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoCrypt To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Examine the JPG bytes again.  The bytes should be different because they are encrypted:
    Get ComGetEncoded Of hoJpgBytes "base64_mime" To sTemp1
    Showln sTemp1

    // Sample base64_mime encrypted JPG data:

    // 	sbz0babt1WCkQf5xKMdg/baZAcUBO5GVUUDF2BjVqmd+HrqKN+t6hAcqakL/bdo0q9hYmow0Tp1e
    // 	AQ9V9DOiifQUZqWVkR+kL/c45bq8JGFDvgNl0djPt+yYhV789IB/fPH0upx+/ad++WNOlv1IxGMr
    // 	Y1x1oERU/IsiEzafUJdI4kZ6FQo2IPGMF/Rm1h79I7hP1yYUFxvJyz+PzaySAUH1nLsNHyDVY5VY
    // 	O90aH3steRSYbz8C8UF9wQ3qqEIXQNnnixvoNDnmHyY39VoVBI5F6rnPwYDfAk2t8tmuryFqvwAu
    // 	...

    // Decrypt to restore back to the original:
    Get pvComObject of hoJpgBytes to vJpgBytes
    Get ComDecryptBd Of hoCrypt vJpgBytes To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoCrypt To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Get ComGetEncoded Of hoJpgBytes "base64_mime" To sTemp1
    Showln sTemp1

    // 	/9j/4AAQSkZJRgABAgEASABIAAD/7Q18UGhvdG9zaG9wIDMuMAA4QklNA+0AAAAAABAASAAAAAEA
    // 	AQBIAAAAAQABOEJJTQPzAAAAAAAIAAAAAAAAAAE4QklNBAoAAAAAAAEAADhCSU0nEAAAAAAACgAB
    // 	AAAAAAAAAAI4QklNA/UAAAAAAEgAL2ZmAAEAbGZmAAYAAAAAAAEAL2ZmAAEAoZmaAAYAAAAAAAEA
    // 	MgAAAAEAWgAAAAYAAAAAAAEANQAAAAEALQAAAAYAAAAAAAE4QklNBBQAAAAAAAQAAAABOEJJTQQM
    // 	...

    // ----------------------------------------------------------------------------------
    // To do chacha20 encryption, just change the settings:

    Set ComCryptAlgorithm Of hoCrypt To "chacha20"
    Set ComKeyLength Of hoCrypt To 256
    // The initial count is the initial block counter for the chacha20 algorithm.
    // It can be any integer, but must be set to the same when decrypting.
    Set ComInitialCount Of hoCrypt To 22

    Get pvComObject of hoJpgBytes to vJpgBytes
    Get ComEncryptBd Of hoCrypt vJpgBytes To iSuccess
    // jpgBytes now contains chacha20 encrypted bytes.

    Get pvComObject of hoJpgBytes to vJpgBytes
    Get ComDecryptBd Of hoCrypt vJpgBytes To iSuccess
    // jpgBytes is now restored back to the original unencrypted by bytes.

    // Save the bytes to a file..
    Get ComWriteFile Of hoJpgBytes "qa_output/starfish.jpg" To iSuccess

    Showln "Success."


End_Procedure