如何通过PHP脚本在Linux服务器上实现数据加密

$config = [
    "digest_alg" => "sha512",
    "private_key_bits" => 4096,
    "private_key_type" => OPENSSL_KEYTYPE_RSA,
];

$res = openssl_pkey_new($config);
openssl_pkey_export($res, $privateKey);
$publicKey = openssl_pkey_get_details($res)['key'];

// 保存私钥和公钥到文件
file_put_contents("private_key.pem", $privateKey);
file_put_contents("public_key.pem", $publicKey);

$publicKey = file_get_contents("public_key.pem");

$data = "要加密的数据";
openssl_public_encrypt($data, $encryptedData, $publicKey);

// 将加密后的数据保存到文件或传输到网络
file_put_contents("encrypted_data.txt", base64_encode($encryptedData));

$privateKey = file_get_contents("private_key.pem");

$encryptedData = file_get_contents("encrypted_data.txt");
$encryptedData = base64_decode($encryptedData);

openssl_private_decrypt($encryptedData, $decryptedData, $privateKey);

echo $decryptedData;