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 <C_CkJwsW.h>
#include <C_CkJsonObjectW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkJwsW jws;
    HCkJsonObjectW header;
    BOOL bIncludeBom;
    const wchar_t *base64Key;
    const wchar_t *jwsCompact;

    success = FALSE;

    jws = CkJwsW_Create();

    //  Protected header specifying HMAC-SHA256.
    header = CkJsonObjectW_Create();
    CkJsonObjectW_UpdateString(header,L"alg",L"HS256");
    success = CkJwsW_SetProtectedHeader(jws,0,header);
    if (success == FALSE) {
        wprintf(L"%s\n",CkJwsW_lastErrorText(jws));
        CkJwsW_Dispose(jws);
        CkJsonObjectW_Dispose(header);
        return;
    }

    bIncludeBom = FALSE;
    success = CkJwsW_SetPayload(jws,L"This is the content to sign.",L"utf-8",bIncludeBom);
    if (success == FALSE) {
        wprintf(L"%s\n",CkJwsW_lastErrorText(jws));
        CkJwsW_Dispose(jws);
        CkJsonObjectW_Dispose(header);
        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.
    base64Key = L"YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4eXowMTIzNDU=";
    success = CkJwsW_SetMacKey(jws,0,base64Key,L"base64");
    if (success == FALSE) {
        wprintf(L"%s\n",CkJwsW_lastErrorText(jws));
        CkJwsW_Dispose(jws);
        CkJsonObjectW_Dispose(header);
        return;
    }

    jwsCompact = CkJwsW_createJws(jws);
    if (CkJwsW_getLastMethodSuccess(jws) == FALSE) {
        wprintf(L"%s\n",CkJwsW_lastErrorText(jws));
        CkJwsW_Dispose(jws);
        CkJsonObjectW_Dispose(header);
        return;
    }

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


    CkJwsW_Dispose(jws);
    CkJsonObjectW_Dispose(header);

    }