(DataFlex) RSA Encrypt and Decrypt Strings

DataFlex sample code to RSA public-key encrypt and decrypt strings using public and private keys.

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

Use ChilkatAx-win32.pkg

Procedure Test
    Handle hoRsa
    Boolean iSuccess
    String sPublicKey
    String sPrivateKey
    String sPlainText
Encryptor    Handle hoRsaEncryptor
    Boolean iUsePrivateKey
    String sEncryptedStr
Decryptor    Handle hoRsaDecryptor
    String sDecryptedStr
    String sTemp1

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

    Get Create (RefClass(cComChilkatRsa)) To hoRsa
    If (Not(IsComObjectCreated(hoRsa))) Begin
        Send CreateComObject of hoRsa
    End

    // This example also generates the public and private
    // keys to be used in the RSA encryption.
    // Normally, you would generate a key pair once,
    // and distribute the public key to your partner.
    // Anything encrypted with the public key can be
    // decrypted with the private key.  The reverse is 
    // also true: anything encrypted using the private
    // key can be decrypted using the public key.

    // Generate a 1024-bit key.  Chilkat RSA supports
    // key sizes ranging from 512 bits to 4096 bits.
    Get ComGenerateKey Of hoRsa 1024 To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoRsa To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Keys are exported in XML format:
    Get ComExportPublicKey Of hoRsa To sPublicKey
    Get ComExportPrivateKey Of hoRsa To sPrivateKey

    Move "Encrypting and decrypting should be easy!" To sPlainText

    // Start with a new RSA object to demonstrate that all we
    // need are the keys previously exported:
    Get Create (RefClass(cComChilkatRsa)) To hoRsaEncryptor
    If (Not(IsComObjectCreated(hoRsaEncryptor))) Begin
        Send CreateComObject of hoRsaEncryptor
    End

    // Encrypted output is always binary.  In this case, we want
    // to encode the encrypted bytes in a printable string.
    // Our choices are "hex", "base64", "url", "quoted-printable".
    Set ComEncodingMode Of hoRsaEncryptor To "hex"

    // We'll encrypt with the public key and decrypt with the private
    // key.  It's also possible to do the reverse.
    Get ComImportPublicKey Of hoRsaEncryptor sPublicKey To iSuccess

    Move False To iUsePrivateKey
    Get ComEncryptStringENC Of hoRsaEncryptor sPlainText iUsePrivateKey To sEncryptedStr
    Showln sEncryptedStr

    // Now decrypt:
    Get Create (RefClass(cComChilkatRsa)) To hoRsaDecryptor
    If (Not(IsComObjectCreated(hoRsaDecryptor))) Begin
        Send CreateComObject of hoRsaDecryptor
    End

    Set ComEncodingMode Of hoRsaDecryptor To "hex"
    Get ComImportPrivateKey Of hoRsaDecryptor sPrivateKey To iSuccess

    Move True To iUsePrivateKey
    Get ComDecryptStringENC Of hoRsaDecryptor sEncryptedStr iUsePrivateKey To sDecryptedStr

    Showln sDecryptedStr


End_Procedure