PHPSession怎么加密_PHPSession数据加密方法及安全存储。

<?php
class EncryptedSessionHandler implements SessionHandlerInterface {
    private $key;
    private $cipher = 'AES-256-CBC';
<pre class="brush:php;toolbar:false;"><pre class="brush:php;toolbar:false;">public function __construct($encryptionKey) {
    // 建议使用 hash 生成固定长度密钥
    $this->key = hash('sha256', $encryptionKey, true);
}

public function open($savePath, $sessionName) {
    return true;
}

public function close() {
    return true;
}

public function read($id) {
    $data = @file_get_contents("$savePath/sess_$id");
    if (!$data) return '';

    $ivLength = openssl_cipher_iv_length($this->cipher);
    $iv = substr($data, 0, $ivLength);
    $encrypted = substr($data, $ivLength);

    $decrypted = openssl_decrypt($encrypted, $this->cipher, $this->key, 0, $iv);
    return $decrypted ? $decrypted : '';
}

public function write($id, $data) {
    $iv = openssl_random_pseudo_bytes(openssl_cipher_iv_length($this->cipher));
    $encrypted = openssl_encrypt($data, $this->cipher, $this->key, 0, $iv);
    $data = $iv . $encrypted;

    return file_put_contents("$savePath/sess_$id", $data) !== false;
}

public function destroy($id) {
    $path = "$savePath/sess_$id";
    if (file_exists($path)) {
        unlink($path);
    }
    return true;
}

public function gc($maxlifetime) {
    foreach (glob("$savePath/sess_*") as $file) {
        if (filemtime($file) + $maxlifetime < time() && file_exists($file)) {
            unlink($file);
        }
    }
    return true;
}

$handler = new EncryptedSessionHandler('your-strong-secret-key');
session_set_save_handler($handler, true);
session_start();