Unicode C
Unicode C
Set JWE Additional Authenticated Data
See more JSON Web Encryption (JWE) Examples
Demonstrates Jwe.SetAad, which sets external Additional Authenticated Data (AAD) for a JWE being encrypted, encoding the supplied text with the given charset.
Background. AAD is integrity-protected but not encrypted, binding external context to the ciphertext. The same AAD must be supplied again when decrypting.
Chilkat Unicode C Downloads
#include <C_CkJweW.h>
#include <C_CkJsonObjectW.h>
#include <C_CkStringBuilderW.h>
void ChilkatSample(void)
{
BOOL success;
HCkJweW jwe;
HCkJsonObjectW header;
const wchar_t *base64Key;
HCkStringBuilderW sbContent;
HCkStringBuilderW sbJwe;
success = FALSE;
jwe = CkJweW_Create();
// Protected header: AES key-wrap with AES-256-GCM content encryption.
header = CkJsonObjectW_Create();
CkJsonObjectW_UpdateString(header,L"alg",L"A256KW");
CkJsonObjectW_UpdateString(header,L"enc",L"A256GCM");
success = CkJweW_SetProtectedHeader(jwe,header);
if (success == FALSE) {
wprintf(L"%s\n",CkJweW_lastErrorText(jwe));
CkJweW_Dispose(jwe);
CkJsonObjectW_Dispose(header);
return;
}
// The 256-bit key-wrapping key (base64) for recipient index 0. In production, obtain the key from a
// secure source rather than hard-coding it.
base64Key = L"YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4eXowMTIzNDU=";
success = CkJweW_SetWrappingKey(jwe,0,base64Key,L"base64");
if (success == FALSE) {
wprintf(L"%s\n",CkJweW_lastErrorText(jwe));
CkJweW_Dispose(jwe);
CkJsonObjectW_Dispose(header);
return;
}
// Set external Additional Authenticated Data (AAD). The AAD is integrity-protected but not
// encrypted, and must be supplied again when decrypting.
success = CkJweW_SetAad(jwe,L"context-info-v1",L"utf-8");
if (success == FALSE) {
wprintf(L"%s\n",CkJweW_lastErrorText(jwe));
CkJweW_Dispose(jwe);
CkJsonObjectW_Dispose(header);
return;
}
sbContent = CkStringBuilderW_Create();
CkStringBuilderW_Append(sbContent,L"This is the secret content.");
sbJwe = CkStringBuilderW_Create();
success = CkJweW_EncryptSb(jwe,sbContent,L"utf-8",sbJwe);
if (success == FALSE) {
wprintf(L"%s\n",CkJweW_lastErrorText(jwe));
CkJweW_Dispose(jwe);
CkJsonObjectW_Dispose(header);
CkStringBuilderW_Dispose(sbContent);
CkStringBuilderW_Dispose(sbJwe);
return;
}
wprintf(L"%s\n",CkStringBuilderW_getAsString(sbJwe));
CkJweW_Dispose(jwe);
CkJsonObjectW_Dispose(header);
CkStringBuilderW_Dispose(sbContent);
CkStringBuilderW_Dispose(sbJwe);
}