(DataFlex) JWE using RSAES-OAEP and AES GCM

This example duplicates the example A.1 in RFC 7516 for JSON Web Encryption (JWE).

Note: This example requires Chilkat v9.5.0.66 or greater.

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

Use ChilkatAx-win32.pkg

Procedure Test
    Boolean iSuccess
    String sPlaintext
ProtHdr    Handle hoJweProtHdr
    Handle hoSbJwk
    Variant vRsaPrivKey
    Handle hoRsaPrivKey
    Variant vRsaPubKey
    Handle hoRsaPubKey
    Handle hoJwe
    String sStrJwe
2    Handle hoJwe2
    String sOriginalPlaintext
    Variant vSbJwe
    Handle hoSbJwe
    String sTemp1
    Boolean bTemp1

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

    // Note: This example requires Chilkat v9.5.0.66 or greater.

    Move "The true sign of intelligence is not knowledge but imagination." To sPlaintext

    // ---------------------------------
    // A.1.1 JOSE Header
    // First build the JWE Protected Header.
    // We want to build this: {"alg":"RSA-OAEP","enc":"A256GCM"}
    Get Create (RefClass(cComChilkatJsonObject)) To hoJweProtHdr
    If (Not(IsComObjectCreated(hoJweProtHdr))) Begin
        Send CreateComObject of hoJweProtHdr
    End
    Get ComAppendString Of hoJweProtHdr "alg" "RSA-OAEP" To iSuccess
    Get ComAppendString Of hoJweProtHdr "enc" "A256GCM" To iSuccess
    Get ComEmit Of hoJweProtHdr To sTemp1
    Showln "JWE Protected Header: " sTemp1
    Showln "--"

    // ---------------------------------
    // A.1.2 Content Encryption Key
    // Note: Chilkat automatically generates the random CEK internally.
    // The application does not need to explicitly take this step.

    // ---------------------------------
    // A.1.3.  Key Encryption
    // The application should load an RSA private key from any format.
    // However, the application does not need to explicitly construct the JWE Encrypted Key.
    // Chilkat automatically does it internally.
    // The design of the Chilkat JWE API is to allow the application to create the JWE
    // after specifying the inputs.  (This is in contrast to forcing the application developer
    // to painstakingly go through each step of the JWE construction process.)

    // The specific RSA key used in the A.1 example is the following JWK:
    Get Create (RefClass(cComChilkatStringBuilder)) To hoSbJwk
    If (Not(IsComObjectCreated(hoSbJwk))) Begin
        Send CreateComObject of hoSbJwk
    End
    Get ComAppend Of hoSbJwk '{"kty": "RSA",' To iSuccess
    Get ComAppend Of hoSbJwk '"n": "oahUIoWw0K0usKNuOR6H4wkf4oBUXHTxRvgb48E-BVvxkeDNjbC4he8rUW' To iSuccess
    Get ComAppend Of hoSbJwk "cJoZmds2h7M70imEVhRU5djINXtqllXI4DFqcI1DgjT9LewND8MW2Krf3S" To iSuccess
    Get ComAppend Of hoSbJwk "psk_ZkoFnilakGygTwpZ3uesH-PFABNIUYpOiN15dsQRkgr0vEhxN92i2a" To iSuccess
    Get ComAppend Of hoSbJwk "sbOenSZeyaxziK72UwxrrKoExv6kc5twXTq4h-QChLOln0_mtUZwfsRaMS" To iSuccess
    Get ComAppend Of hoSbJwk "tPs6mS6XrgxnxbWhojf663tuEQueGC-FCMfra36C9knDFGzKsNa7LZK2dj" To iSuccess
    Get ComAppend Of hoSbJwk 'YgyD3JR_MB_4NUJW_TqOQtwHYbxevoJArm-L5StowjzGy-_bq6Gw",' To iSuccess
    Get ComAppend Of hoSbJwk '"e": "AQAB",' To iSuccess
    Get ComAppend Of hoSbJwk '"d": "kLdtIj6GbDks_ApCSTYQtelcNttlKiOyPzMrXHeI-yk1F7-kpDxY4-WY5N' To iSuccess
    Get ComAppend Of hoSbJwk "WV5KntaEeXS1j82E375xxhWMHXyvjYecPT9fpwR_M9gV8n9Hrh2anTpTD9" To iSuccess
    Get ComAppend Of hoSbJwk "3Dt62ypW3yDsJzBnTnrYu1iwWRgBKrEYY46qAZIrA2xAwnm2X7uGR1hghk" To iSuccess
    Get ComAppend Of hoSbJwk "qDp0Vqj3kbSCz1XyfCs6_LehBwtxHIyh8Ripy40p24moOAbgxVw3rxT_vl" To iSuccess
    Get ComAppend Of hoSbJwk "t3UVe4WO3JkJOzlpUf-KTVI2Ptgm-dARxTEtE-id-4OJr0h-K-VFs3VSnd" To iSuccess
    Get ComAppend Of hoSbJwk 'VTIznSxfyrj8ILL6MG_Uv8YAu7VILSB3lOW085-4qE3DzgrTjgyQ",' To iSuccess
    Get ComAppend Of hoSbJwk '"p": "1r52Xk46c-LsfB5P442p7atdPUrxQSy4mti_tZI3Mgf2EuFVbUoDBvaRQ-' To iSuccess
    Get ComAppend Of hoSbJwk "SWxkbkmoEzL7JXroSBjSrK3YIQgYdMgyAEPTPjXv_hI2_1eTSPVZfzL0lf" To iSuccess
    Get ComAppend Of hoSbJwk 'fNn03IXqWF5MDFuoUYE0hzb2vhrlN_rKrbfDIwUbTrjjgieRbwC6Cl0",' To iSuccess
    Get ComAppend Of hoSbJwk '"q": "wLb35x7hmQWZsWJmB_vle87ihgZ19S8lBEROLIsZG4ayZVe9Hi9gDVCOBm' To iSuccess
    Get ComAppend Of hoSbJwk "UDdaDYVTSNx_8Fyw1YYa9XGrGnDew00J28cRUoeBB_jKI1oma0Orv1T9aX" To iSuccess
    Get ComAppend Of hoSbJwk 'IWxKwd4gvxFImOWr3QRL9KEBRzk2RatUBnmDZJTIAfwTs0g68UZHvtc",' To iSuccess
    Get ComAppend Of hoSbJwk '"dp": "ZK-YwE7diUh0qR1tR7w8WHtolDx3MZ_OTowiFvgfeQ3SiresXjm9gZ5KL' To iSuccess
    Get ComAppend Of hoSbJwk "hMXvo-uz-KUJWDxS5pFQ_M0evdo1dKiRTjVw_x4NyqyXPM5nULPkcpU827" To iSuccess
    Get ComAppend Of hoSbJwk 'rnpZzAJKpdhWAgqrXGKAECQH0Xt4taznjnd_zVpAmZZq60WPMBMfKcuE",' To iSuccess
    Get ComAppend Of hoSbJwk '"dq": "Dq0gfgJ1DdFGXiLvQEZnuKEN0UUmsJBxkjydc3j4ZYdBiMRAy86x0vHCj' To iSuccess
    Get ComAppend Of hoSbJwk "ywcMlYYg4yoC4YZa9hNVcsjqA3FeiL19rk8g6Qn29Tt0cj8qqyFpz9vNDB" To iSuccess
    Get ComAppend Of hoSbJwk 'UfCAiJVeESOjJDZPYHdHY8v1b-o-Z2X5tvLx-TCekf7oxyeKDUqKWjis",' To iSuccess
    Get ComAppend Of hoSbJwk '"qi": "VIMpMYbPf47dT1w_zDUXfPimsSegnMOA1zTaX7aGk_8urY6R8-ZW1FxU7' To iSuccess
    Get ComAppend Of hoSbJwk "AlWAyLWybqq6t16VFd7hQd0y6flUK4SlOydB61gwanOsXGOAOv82cHq0E3" To iSuccess
    Get ComAppend Of hoSbJwk 'eL4HrtZkUuKvnPrMnsUUFlfUdybVzxyjz9JF_XyaY14ardLSjf4L_FNY"}' To iSuccess

    // Load this JWK into a Chilkat private key object.
    Get Create (RefClass(cComChilkatPrivateKey)) To hoRsaPrivKey
    If (Not(IsComObjectCreated(hoRsaPrivKey))) Begin
        Send CreateComObject of hoRsaPrivKey
    End
    Get ComGetAsString Of hoSbJwk To sTemp1
    Get ComLoadJwk Of hoRsaPrivKey sTemp1 To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoRsaPrivKey To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // The public key is used to encrypt (i.e. create the JWE), 
    // and the private key is used to decrypt.
    // The RSA public key is simply a subset of the private key.  The RSA public key
    // is composed of the "n" and "e" members shown above.  These are also known as the
    // modulus and exponent.
    // We can simply get the public key object from the private key object
    Get ComGetPublicKey Of hoRsaPrivKey To vRsaPubKey
    If (IsComObject(vRsaPubKey)) Begin
        Get Create (RefClass(cComChilkatPublicKey)) To hoRsaPubKey
        Set pvComObject Of hoRsaPubKey To vRsaPubKey
    End

    // ---------------------------------
    // A.1.4.  Initialization Vector
    // Chilkat automatically generates the necessary random IV internally.  
    // The application does not need to do this explicitly.

    // ---------------------------------
    // A.1.5.  Additional Authenticated Data
    // The Additional Authenticated Data encryption parameter is
    // ASCII(BASE64URL(UTF8(JWE Protected Header))).
    // Again, Chilkat automatically takes care of this internally.
    // The application does not need to explicitly take this step.

    // ---------------------------------
    // A.1.6.  Content Encryption
    // Again... this step is handled by Chilkat internally.

    // ---------------------------------
    // A.1.7.  Complete Representation
    // The application need only call the Encrypt, EncryptSb, or EncryptBd method
    // return the fully assembled JWE.  
    // The final representation in the Compact Serialization 
    // is the string BASE64URL(UTF8(JWE Protected Header)) || '.' ||
    // BASE64URL(JWE Encrypted Key) || '.' || BASE64URL(JWE Initialization
    // Vector) || '.' || BASE64URL(JWE Ciphertext) || '.' || BASE64URL(JWE
    // Authentication Tag).

    Get Create (RefClass(cComChilkatJwe)) To hoJwe
    If (Not(IsComObjectCreated(hoJwe))) Begin
        Send CreateComObject of hoJwe
    End
    Get pvComObject of hoJweProtHdr to vJweProtHdr
    Get ComSetProtectedHeader Of hoJwe vJweProtHdr To iSuccess
    Get ComSetPublicKey Of hoJwe 0 vRsaPubKey To iSuccess
    Send Destroy of hoRsaPubKey

    Get ComEncrypt Of hoJwe sPlaintext "utf-8" To sStrJwe
    Get ComLastMethodSuccess Of hoJwe To bTemp1
    If (bTemp1 <> True) Begin
        Get ComLastErrorText Of hoJwe To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Note: The RSA OAEP algorithm uses random padding bytes internally.
    // Therefore, the results will appear different each time -- even if the
    // identical plaintext is encrypted with the identical RSA key. 
    // (Do not expect the appearance of the results to be the same as what
    // is published in the RFC.  However, what is published in the RFC *should*
    // be decryptable using the code that follows.)
    Showln sStrJwe

    // Let's decrypt the JWE that was just produced.
    // Do the following to decrypt a JWE:
    // 1) Load the JWE.
    // 2) Set the private key for decryption.
    // 3) Decrypt.
    Get Create (RefClass(cComChilkatJwe)) To hoJwe2
    If (Not(IsComObjectCreated(hoJwe2))) Begin
        Send CreateComObject of hoJwe2
    End
    Get ComLoadJwe Of hoJwe2 sStrJwe To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoJwe2 To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Provide the RSA private key for decryption.
    // (The JWE was encrypted for a single recipient at index 0.)
    Get pvComObject of hoRsaPrivKey to vRsaPrivKey
    Get ComSetPrivateKey Of hoJwe2 0 vRsaPrivKey To iSuccess

    // Decrypt.
    Get ComDecrypt Of hoJwe2 0 "utf-8" To sOriginalPlaintext
    Get ComLastMethodSuccess Of hoJwe2 To bTemp1
    If (bTemp1 <> True) Begin
        Get ComLastErrorText Of hoJwe2 To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Showln "original text: "
    Showln sOriginalPlaintext

    // ---------------------------------------------------------------------------------
    // It should also be possible to decrypt the JWE as shown in RFC 7516, Appendix A.1.7
    // because it was produced using the same RSA key.

    Get Create (RefClass(cComChilkatStringBuilder)) To hoSbJwe
    If (Not(IsComObjectCreated(hoSbJwe))) Begin
        Send CreateComObject of hoSbJwe
    End
    Get ComAppend Of hoSbJwe "eyJhbGciOiJSU0EtT0FFUCIsImVuYyI6IkEyNTZHQ00ifQ." To iSuccess
    Get ComAppend Of hoSbJwe "OKOawDo13gRp2ojaHV7LFpZcgV7T6DVZKTyKOMTYUmKoTCVJRgckCL9kiMT03JGe" To iSuccess
    Get ComAppend Of hoSbJwe "ipsEdY3mx_etLbbWSrFr05kLzcSr4qKAq7YN7e9jwQRb23nfa6c9d-StnImGyFDb" To iSuccess
    Get ComAppend Of hoSbJwe "Sv04uVuxIp5Zms1gNxKKK2Da14B8S4rzVRltdYwam_lDp5XnZAYpQdb76FdIKLaV" To iSuccess
    Get ComAppend Of hoSbJwe "mqgfwX7XWRxv2322i-vDxRfqNzo_tETKzpVLzfiwQyeyPGLBIO56YJ7eObdv0je8" To iSuccess
    Get ComAppend Of hoSbJwe "1860ppamavo35UgoRdbYaBcoh9QcfylQr66oc6vFWXRcZ_ZT2LawVCWTIy3brGPi" To iSuccess
    Get ComAppend Of hoSbJwe "6UklfCpIMfIjf7iGdXKHzg." To iSuccess
    Get ComAppend Of hoSbJwe "48V1_ALb6US04U3b." To iSuccess
    Get ComAppend Of hoSbJwe "5eym8TW_c8SuK0ltJ3rpYIzOeDQz7TALvtu6UG9oMo4vpzs9tX_EFShS8iB7j6ji" To iSuccess
    Get ComAppend Of hoSbJwe "SdiwkIr3ajwQzaBtQD_A." To iSuccess
    Get ComAppend Of hoSbJwe "XFBoMYUZodetZdvTiFvSkQ" To iSuccess

    Get pvComObject of hoSbJwe to vSbJwe
    Get ComLoadJweSb Of hoJwe2 vSbJwe To iSuccess
    If (iSuccess <> True) Begin
        Get ComLastErrorText Of hoJwe2 To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Provide the RSA private key for decryption.
    Get pvComObject of hoRsaPrivKey to vRsaPrivKey
    Get ComSetPrivateKey Of hoJwe2 0 vRsaPrivKey To iSuccess

    // Decrypt.
    Get ComDecrypt Of hoJwe2 0 "utf-8" To sOriginalPlaintext
    Get ComLastMethodSuccess Of hoJwe2 To bTemp1
    If (bTemp1 <> True) Begin
        Get ComLastErrorText Of hoJwe2 To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Showln sOriginalPlaintext


End_Procedure