DataFlex
DataFlex
JWE Using Flattened JWE JSON Serialization
See more JSON Web Encryption (JWE) Examples
This example duplicates the example A.5 in RFC 7516 for JSON Web Encryption (JWE).This example demonstrates using the flattened JWE JSON Serialization syntax. This example demonstrates the capability for encrypting the plaintext to a single recipient in a flattened JSON structure.
Note: This example requires Chilkat v9.5.0.66 or greater.
Chilkat DataFlex Downloads
Use ChilkatAx-win32.pkg
Procedure Test
Boolean iSuccess
String sPlaintext
Handle hoJwe
ProtHdr Handle hoJweProtHdr
RecipientHdr Handle hoJweRecipientHdr
Integer iRecipientIndex
UnprotHdr Handle hoJweUnprotHdr
String sAesWrappingKey
String sStrJwe
Handle hoJsonTemp
2 Handle hoJwe2
String sOriginalPlaintext
Variant vSbJwe
Handle hoSbJwe
String sTemp1
Boolean bTemp1
Move False To iSuccess
// 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 "Live long and prosper." To sPlaintext
Get Create (RefClass(cComChilkatJwe)) To hoJwe
If (Not(IsComObjectCreated(hoJwe))) Begin
Send CreateComObject of hoJwe
End
// First build the JWE Protected Header: {"enc":"A128CBC-HS256"}
Get Create (RefClass(cComChilkatJsonObject)) To hoJweProtHdr
If (Not(IsComObjectCreated(hoJweProtHdr))) Begin
Send CreateComObject of hoJweProtHdr
End
Get ComAppendString Of hoJweProtHdr "enc" "A128CBC-HS256" To iSuccess
Get pvComObject of hoJweProtHdr to vJweProtHdr
Get ComSetProtectedHeader Of hoJwe vJweProtHdr To iSuccess
// We have a single recipient that uses AES Key Wrap to encrypt the CEK.
//
// {"alg":"A128KW","kid":"7"}
Get Create (RefClass(cComChilkatJsonObject)) To hoJweRecipientHdr
If (Not(IsComObjectCreated(hoJweRecipientHdr))) Begin
Send CreateComObject of hoJweRecipientHdr
End
Get ComAppendString Of hoJweRecipientHdr "alg" "A128KW" To iSuccess
Get ComAppendString Of hoJweRecipientHdr "kid" "7" To iSuccess
Move 0 To iRecipientIndex
Get pvComObject of hoJweRecipientHdr to vJweRecipientHdr
Get ComSetRecipientHeader Of hoJwe iRecipientIndex vJweRecipientHdr To iSuccess
// Set the Shared Unprotected Header: {"jku":"https://server.example.com/keys.jwks"}
Get Create (RefClass(cComChilkatJsonObject)) To hoJweUnprotHdr
If (Not(IsComObjectCreated(hoJweUnprotHdr))) Begin
Send CreateComObject of hoJweUnprotHdr
End
Get ComAppendString Of hoJweUnprotHdr "jku" "https://server.example.com/keys.jwks" To iSuccess
Get pvComObject of hoJweUnprotHdr to vJweUnprotHdr
Get ComSetUnprotectedHeader Of hoJwe vJweUnprotHdr To iSuccess
// Set the AES key wrapping key.
Move "GawgguFyGrWKav7AX4VKUg" To sAesWrappingKey
Move 0 To iRecipientIndex
Get ComSetWrappingKey Of hoJwe iRecipientIndex sAesWrappingKey "base64url" To iSuccess
// OK.. everything has been specified.
// Now encrypt.
// Indicate that we prefer the flattened JSON serialization.
Set ComPreferFlattened Of hoJwe To True
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
// The JWE is produced in the most compact form possible (a single line).
// Let's load it into a JSON object and examine in a non-compact pretty-printed format:
Get Create (RefClass(cComChilkatJsonObject)) To hoJsonTemp
If (Not(IsComObjectCreated(hoJsonTemp))) Begin
Send CreateComObject of hoJsonTemp
End
Get ComLoad Of hoJsonTemp sStrJwe To iSuccess
Set ComEmitCompact Of hoJsonTemp To False
Get ComEmit Of hoJsonTemp To sTemp1
Showln sTemp1
// The JWE looks like this:
// (Note: Because of random values used in the encryption process, your encrypted results will be different.)
// {
// "protected": "eyJlbmMiOiJBMTI4Q0JDLUhTMjU2In0",
// "unprotected": {
// "jku": "https://server.example.com/keys.jwks"
// },
// "header": {
// "alg": "A128KW",
// "kid": "7"
// },
// "encrypted_key": "FW7z9VxOvnF2ClicvUT4HTeqcdyh90C6qytfEFJsOb77FOwTfYrc3w",
// "iv": "O6Ly5-eML3zTs-_fNX3D5Q",
// "ciphertext": "Q8NLmeac9JhLh0CQPuG_7D9wVDb55eToCh0g5-FQ4M0",
// "tag": "slzlo6-J9C7wSDF4dh_kBg"
// }
// Now decrypt......................................
// First, load the JWE..
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
// Set the AES wrap key..
Move 0 To iRecipientIndex
Get ComSetWrappingKey Of hoJwe2 iRecipientIndex sAesWrappingKey "base64url" To iSuccess
// Decrypt
Get ComDecrypt Of hoJwe2 iRecipientIndex "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 decrypted with AES key wrap key: "
Showln sOriginalPlaintext
// ---------------------------------------------------------------------------------
// It should also be possible to decrypt the flattened JWE as shown in RFC 7516, Appendix A.5
// because it was produced using the same key.
Get Create (RefClass(cComChilkatStringBuilder)) To hoSbJwe
If (Not(IsComObjectCreated(hoSbJwe))) Begin
Send CreateComObject of hoSbJwe
End
Get ComAppend Of hoSbJwe "{" To iSuccess
Get ComAppend Of hoSbJwe '"protected":' To iSuccess
Get ComAppend Of hoSbJwe '"eyJlbmMiOiJBMTI4Q0JDLUhTMjU2In0",' To iSuccess
Get ComAppend Of hoSbJwe '"unprotected":' To iSuccess
Get ComAppend Of hoSbJwe '{"jku":"https://server.example.com/keys.jwks"},' To iSuccess
Get ComAppend Of hoSbJwe '"header":' To iSuccess
Get ComAppend Of hoSbJwe '{"alg":"A128KW","kid":"7"},' To iSuccess
Get ComAppend Of hoSbJwe '"encrypted_key":' To iSuccess
Get ComAppend Of hoSbJwe '"6KB707dM9YTIgHtLvtgWQ8mKwboJW3of9locizkDTHzBC2IlrT1oOQ",' To iSuccess
Get ComAppend Of hoSbJwe '"iv":' To iSuccess
Get ComAppend Of hoSbJwe '"AxY8DCtDaGlsbGljb3RoZQ",' To iSuccess
Get ComAppend Of hoSbJwe '"ciphertext":' To iSuccess
Get ComAppend Of hoSbJwe '"KDlTtXchhZTGufMYmOYGS4HffxPSUrfmqCHXaI9wOGY",' To iSuccess
Get ComAppend Of hoSbJwe '"tag":' To iSuccess
Get ComAppend Of hoSbJwe '"Mz-VPPyU4RlcuYv1IwIvzw"' To iSuccess
Get ComAppend Of hoSbJwe "}" 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
Move 0 To iRecipientIndex
Get ComSetWrappingKey Of hoJwe2 iRecipientIndex sAesWrappingKey "base64url" To iSuccess
Get ComDecrypt Of hoJwe2 iRecipientIndex "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 decrypted from published flattened JWE: "
Showln sOriginalPlaintext
// The output:
// original text decrypted with AES key wrap key:
// Live long and prosper.
// original text decrypted from published flattened JWE:
// Live long and prosper.
End_Procedure