['size' => 16, 'aead' => false], 'aes-256-cbc' => ['size' => 32, 'aead' => false], 'aes-128-gcm' => ['size' => 16, 'aead' => true], 'aes-256-gcm' => ['size' => 32, 'aead' => true], ]; function generateKey($cipher = 'aes-128-cbc') { return random_bytes($supportedCiphers[strtolower($cipher)]['size'] ?? 32); } $app_key = 'base64:' . base64_encode(generateKey()); echo ''.$app_key.''; @unlink('app_key.php'); ?>