Sign a JWS with an HMAC Key

See more JSON Web Signatures (JWS) Examples

Demonstrates Jws.SetMacKey, which sets the symmetric MAC key for a signature. The key bytes are supplied in a named encoding such as hex or base64.

#include <CkJwsW.h>
#include <CkJsonObjectW.h>

void ChilkatSample(void)
    {
    bool success = false;

    CkJwsW jws;

    //  Protected header specifying HMAC-SHA256.
    CkJsonObjectW header;
    header.UpdateString(L"alg",L"HS256");
    success = jws.SetProtectedHeader(0,header);
    if (success == false) {
        wprintf(L"%s\n",jws.lastErrorText());
        return;
    }

    bool bIncludeBom = false;
    success = jws.SetPayload(L"This is the content to sign.",L"utf-8",bIncludeBom);
    if (success == false) {
        wprintf(L"%s\n",jws.lastErrorText());
        return;
    }

    //  Set the symmetric MAC key for signature 0.  The key bytes are provided in the named encoding (here
    //  base64).  In production, obtain the key from a secure source rather than hard-coding it.
    const wchar_t *base64Key = L"YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4eXowMTIzNDU=";
    success = jws.SetMacKey(0,base64Key,L"base64");
    if (success == false) {
        wprintf(L"%s\n",jws.lastErrorText());
        return;
    }

    const wchar_t *jwsCompact = jws.createJws();
    if (jws.get_LastMethodSuccess() == false) {
        wprintf(L"%s\n",jws.lastErrorText());
        return;
    }

    wprintf(L"%s\n",jwsCompact);
    }