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DataFlex

JWE using ECDH-ES+A256KW

See more JSON Web Encryption (JWE) Examples

Create a JWE with the following public/private key pair:
{
    "kty": "EC",
    "d": "jZCffzVqJjryBH4EoaN0oD-TyLXrW2XHoDdIuPZnk8c",
    "use": "enc",
    "crv": "P-256",
    "kid": "evEK2thJMsWxBYRivXI8ykUf6n6zizLiLCGH3s58wKs",
    "x": "LOakgGvxWBsWbCPLY6Vq6OuBktIqG8POXFXe7ngQ2oM",
    "y": "voJvS6I-Mc4qqmEA_G2hLQqBck3a3vqaJbmzY7YPUD4",
    "alg": "ECDH-ES+A256KW"
}

Also shows how to decrypt.

Chilkat DataFlex Downloads

DataFlex
Use ChilkatAx-win32.pkg

Procedure Test
    Boolean iSuccess
    Handle hoJson
    Variant vPubkey
    Handle hoPubkey
    Handle hoJwt
    Variant vJweProtHdr
    Handle hoJweProtHdr
    Handle hoJwe
    String sPlainText
    String sStrJwe
    Variant vPrivkey
    Handle hoPrivkey
2    Handle hoJwe2
    String sDecryptedText
    String sTemp1
    Integer iTemp1
    Boolean bTemp1

    Move False To iSuccess

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

    // Create the following JSON:
    // {
    //     "kty": "EC",
    //     "d": "jZCffzVqJjryBH4EoaN0oD-TyLXrW2XHoDdIuPZnk8c",
    //     "use": "enc",
    //     "crv": "P-256",
    //     "kid": "evEK2thJMsWxBYRivXI8ykUf6n6zizLiLCGH3s58wKs",
    //     "x": "LOakgGvxWBsWbCPLY6Vq6OuBktIqG8POXFXe7ngQ2oM",
    //     "y": "voJvS6I-Mc4qqmEA_G2hLQqBck3a3vqaJbmzY7YPUD4",
    //     "alg": "ECDH-ES+A256KW"
    // }

    Get Create (RefClass(cComChilkatJsonObject)) To hoJson
    If (Not(IsComObjectCreated(hoJson))) Begin
        Send CreateComObject of hoJson
    End
    Get ComUpdateString Of hoJson "kty" "EC" To iSuccess
    Get ComUpdateString Of hoJson "d" "jZCffzVqJjryBH4EoaN0oD-TyLXrW2XHoDdIuPZnk8c" To iSuccess
    Get ComUpdateString Of hoJson "use" "enc" To iSuccess
    Get ComUpdateString Of hoJson "crv" "P-256" To iSuccess
    Get ComUpdateString Of hoJson "kid" "evEK2thJMsWxBYRivXI8ykUf6n6zizLiLCGH3s58wKs" To iSuccess
    Get ComUpdateString Of hoJson "x" "LOakgGvxWBsWbCPLY6Vq6OuBktIqG8POXFXe7ngQ2oM" To iSuccess
    Get ComUpdateString Of hoJson "y" "voJvS6I-Mc4qqmEA_G2hLQqBck3a3vqaJbmzY7YPUD4" To iSuccess
    Get ComUpdateString Of hoJson "alg" "ECDH-ES+A256KW" To iSuccess

    Get Create (RefClass(cComChilkatPublicKey)) To hoPubkey
    If (Not(IsComObjectCreated(hoPubkey))) Begin
        Send CreateComObject of hoPubkey
    End

    Get ComEmit Of hoJson To sTemp1
    Get ComLoadFromString Of hoPubkey sTemp1 To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoPubkey To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // Build our protected header:

    // 	{
    // 	  "alg": "ECDH-ES+A256KW",
    // 	  "enc": "A256GCM",
    // 	  "exp": 1621957030,
    // 	  "cty": "NJWT",
    // 	  "epk": {
    // 	    "kty": "EC",
    // 	    "x": "QLpJ_LpFx-6yJhsb4OvHwU1khLnviiOwYOvmf5clK7w"
    // 	    "y": "AJh7pJ3zZKDJkm8rbeG69GBooTosXJgSsvNFH0i3Vxnu"
    // 	    "crv": "BP-256"
    // 	  }
    // 	}

    // Use jwt only for getting the current date/time + 3600 seconds.
    Get Create (RefClass(cComChilkatJwt)) To hoJwt
    If (Not(IsComObjectCreated(hoJwt))) Begin
        Send CreateComObject of hoJwt
    End

    Get Create (RefClass(cComChilkatJsonObject)) To hoJweProtHdr
    If (Not(IsComObjectCreated(hoJweProtHdr))) Begin
        Send CreateComObject of hoJweProtHdr
    End
    Get ComUpdateString Of hoJweProtHdr "alg" "ECDH-ES+A256KW" To iSuccess
    Get ComUpdateString Of hoJweProtHdr "enc" "A256GCM" To iSuccess
    Get ComGenNumericDate Of hoJwt 3600 To iTemp1
    Get ComUpdateInt Of hoJweProtHdr "exp" iTemp1 To iSuccess
    Get ComUpdateString Of hoJweProtHdr "cty" "NJWT" To iSuccess
    Get ComUpdateString Of hoJweProtHdr "epk.kty" "EC" To iSuccess
    Get ComUpdateString Of hoJweProtHdr "epk.x" "LOakgGvxWBsWbCPLY6Vq6OuBktIqG8POXFXe7ngQ2oM" To iSuccess
    Get ComUpdateString Of hoJweProtHdr "epk.y" "voJvS6I-Mc4qqmEA_G2hLQqBck3a3vqaJbmzY7YPUD4" To iSuccess
    Get ComUpdateString Of hoJweProtHdr "epk.crv" "P-256" To iSuccess

    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 pvComObject of hoPubkey to vPubkey
    Get ComSetPublicKey Of hoJwe 0 vPubkey To iSuccess

    Move "This is the text to be encrypted." To sPlainText
    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

    Showln sStrJwe

    // Let's decrypt...
    Get Create (RefClass(cComChilkatPrivateKey)) To hoPrivkey
    If (Not(IsComObjectCreated(hoPrivkey))) Begin
        Send CreateComObject of hoPrivkey
    End

    Get ComEmit Of hoJson To sTemp1
    Get ComLoadJwk Of hoPrivkey sTemp1 To iSuccess
    If (iSuccess = False) Begin
        Get ComLastErrorText Of hoPrivkey To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    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 = False) Begin
        Get ComLastErrorText Of hoJwe2 To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Get pvComObject of hoPrivkey to vPrivkey
    Get ComSetPrivateKey Of hoJwe2 0 vPrivkey To iSuccess

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

    Showln sDecryptedText


End_Procedure