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.

use chilkat();

$success = 0;

$jwe = chilkat::CkJwe->new();

#  Protected header: AES key-wrap with AES-256-GCM content encryption.
$header = chilkat::CkJsonObject->new();
$header->UpdateString("alg","A256KW");
$header->UpdateString("enc","A256GCM");
$success = $jwe->SetProtectedHeader($header);
if ($success == 0) {
    print $jwe->lastErrorText() . "\r\n";
    exit;
}

#  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 = "YWJjZGVmZ2hpamtsbW5vcHFyc3R1dnd4eXowMTIzNDU=";
$success = $jwe->SetWrappingKey(0,$base64Key,"base64");
if ($success == 0) {
    print $jwe->lastErrorText() . "\r\n";
    exit;
}

#  Set external Additional Authenticated Data (AAD).  The AAD is integrity-protected but not
#  encrypted, and must be supplied again when decrypting.
$success = $jwe->SetAad("context-info-v1","utf-8");
if ($success == 0) {
    print $jwe->lastErrorText() . "\r\n";
    exit;
}

$sbContent = chilkat::CkStringBuilder->new();
$sbContent->Append("This is the secret content.");
$sbJwe = chilkat::CkStringBuilder->new();
$success = $jwe->EncryptSb($sbContent,"utf-8",$sbJwe);
if ($success == 0) {
    print $jwe->lastErrorText() . "\r\n";
    exit;
}

print $sbJwe->getAsString() . "\r\n";