Set the Optional JWS Unprotected Header

See more JSON Web Signatures (JWS) Examples

Demonstrates Jws.SetUnprotectedHeader, which sets the optional unprotected header for a signature.

Background. Unlike the protected header, the unprotected header is not covered by the signature. It is carried in the JSON serialization forms of a JWS, so producing a JWS with an unprotected header yields a JSON serialization rather than compact form.

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#include <C_CkJws.h>
#include <C_CkJsonObject.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkJws jws;
    HCkJsonObject header;
    HCkJsonObject unprotected;
    BOOL bIncludeBom;
    const char *base64Key;
    const char *jwsJson;

    success = FALSE;

    jws = CkJws_Create();

    //  Protected header specifying HMAC-SHA256.
    header = CkJsonObject_Create();
    CkJsonObject_UpdateString(header,"alg","HS256");
    success = CkJws_SetProtectedHeader(jws,0,header);
    if (success == FALSE) {
        printf("%s\n",CkJws_lastErrorText(jws));
        CkJws_Dispose(jws);
        CkJsonObject_Dispose(header);
        return;
    }

    //  Set the optional unprotected header for signature 0.  Unlike the protected header, it is not
    //  covered by the signature.  It is carried in the JSON serialization forms of a JWS.
    unprotected = CkJsonObject_Create();
    CkJsonObject_UpdateString(unprotected,"kid","signer-key-1");
    success = CkJws_SetUnprotectedHeader(jws,0,unprotected);
    if (success == FALSE) {
        printf("%s\n",CkJws_lastErrorText(jws));
        CkJws_Dispose(jws);
        CkJsonObject_Dispose(header);
        CkJsonObject_Dispose(unprotected);
        return;
    }

    bIncludeBom = FALSE;
    success = CkJws_SetPayload(jws,"This is the content to sign.","utf-8",bIncludeBom);
    if (success == FALSE) {
        printf("%s\n",CkJws_lastErrorText(jws));
        CkJws_Dispose(jws);
        CkJsonObject_Dispose(header);
        CkJsonObject_Dispose(unprotected);
        return;
    }

    base64Key = "YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4eXowMTIzNDU=";
    success = CkJws_SetMacKey(jws,0,base64Key,"base64");
    if (success == FALSE) {
        printf("%s\n",CkJws_lastErrorText(jws));
        CkJws_Dispose(jws);
        CkJsonObject_Dispose(header);
        CkJsonObject_Dispose(unprotected);
        return;
    }

    //  Because an unprotected header is present, the JWS is produced in a JSON serialization form.
    jwsJson = CkJws_createJws(jws);
    if (CkJws_getLastMethodSuccess(jws) == FALSE) {
        printf("%s\n",CkJws_lastErrorText(jws));
        CkJws_Dispose(jws);
        CkJsonObject_Dispose(header);
        CkJsonObject_Dispose(unprotected);
        return;
    }

    printf("%s\n",jwsJson);


    CkJws_Dispose(jws);
    CkJsonObject_Dispose(header);
    CkJsonObject_Dispose(unprotected);

    }