Set the Shared JWE Unprotected Header

See more JSON Web Encryption (JWE) Examples

Demonstrates Jwe.SetUnprotectedHeader, which sets the shared JWE unprotected header from a JsonObject.

<?php

$success = 0;

$jwe = new COM("Chilkat.Jwe");

//  Protected header: AES key-wrap with AES-256-GCM content encryption.
$header = new COM("Chilkat.JsonObject");
$header->UpdateString('alg','A256KW');
$header->UpdateString('enc','A256GCM');
$success = $jwe->SetProtectedHeader($header);
if ($success == 0) {
    print $jwe->LastErrorText . "\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 . "\n";
    exit;
}

//  Set the shared JWE unprotected header.  It is shared by all recipients but, unlike the protected
//  header, is not integrity-protected.
$unprotected = new COM("Chilkat.JsonObject");
$unprotected->UpdateString('cty','text/plain');
$success = $jwe->SetUnprotectedHeader($unprotected);
if ($success == 0) {
    print $jwe->LastErrorText . "\n";
    exit;
}

$sbContent = new COM("Chilkat.StringBuilder");
$sbContent->Append('This is the secret content.');
$sbJwe = new COM("Chilkat.StringBuilder");
$success = $jwe->EncryptSb($sbContent,'utf-8',$sbJwe);
if ($success == 0) {
    print $jwe->LastErrorText . "\n";
    exit;
}

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

?>