PureBasic

Sign a JWS with an HMAC Key from BinData

See more JSON Web Signatures (JWS) Examples

Demonstrates Jws.SetMacKeyBd, which sets the symmetric MAC key for a signature from the raw bytes in a BinData.

Background. This is the in-memory equivalent of SetMacKey, for when the key material is already available as bytes.

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PureBasic

IncludeFile "CkBinData.pb"
IncludeFile "CkJws.pb"
IncludeFile "CkJsonObject.pb"

Procedure ChilkatExample()

    success.i = 0

    jws.i = CkJws::ckCreate()
    If jws.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ;  Protected header specifying HMAC-SHA256.
    header.i = CkJsonObject::ckCreate()
    If header.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkJsonObject::ckUpdateString(header,"alg","HS256")
    success = CkJws::ckSetProtectedHeader(jws,0,header)
    If success = 0
        Debug CkJws::ckLastErrorText(jws)
        CkJws::ckDispose(jws)
        CkJsonObject::ckDispose(header)
        ProcedureReturn
    EndIf

    bIncludeBom.i = 0
    success = CkJws::ckSetPayload(jws,"This is the content to sign.","utf-8",bIncludeBom)
    If success = 0
        Debug CkJws::ckLastErrorText(jws)
        CkJws::ckDispose(jws)
        CkJsonObject::ckDispose(header)
        ProcedureReturn
    EndIf

    ;  Set the symmetric MAC key for signature 0 from the raw bytes in a BinData.  In production, obtain
    ;  the key material from a secure source.
    bdKey.i = CkBinData::ckCreate()
    If bdKey.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkBinData::ckAppendEncoded(bdKey,"YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4eXowMTIzNDU=","base64")
    success = CkJws::ckSetMacKeyBd(jws,0,bdKey)
    If success = 0
        Debug CkJws::ckLastErrorText(jws)
        CkJws::ckDispose(jws)
        CkJsonObject::ckDispose(header)
        CkBinData::ckDispose(bdKey)
        ProcedureReturn
    EndIf

    jwsCompact.s = CkJws::ckCreateJws(jws)
    If CkJws::ckLastMethodSuccess(jws) = 0
        Debug CkJws::ckLastErrorText(jws)
        CkJws::ckDispose(jws)
        CkJsonObject::ckDispose(header)
        CkBinData::ckDispose(bdKey)
        ProcedureReturn
    EndIf

    Debug jwsCompact


    CkJws::ckDispose(jws)
    CkJsonObject::ckDispose(header)
    CkBinData::ckDispose(bdKey)


    ProcedureReturn
EndProcedure