回答

使用hash_hmac结合时间戳实现：

<?php
// 生成加密字符串
function generateToken($data, $secretKey, $expire = 3600) {
    $timestamp = time();
    $dataString = serialize($data); // 序列化数据
    $signature = hash_hmac('sha256', $dataString . $timestamp, $secretKey);
    $token = base64_encode("$dataString.$timestamp.$signature");
    return $token;
}

// 验证加密字符串
function verifyToken($token, $secretKey, $expire = 3600) {
    $decoded = base64_decode($token);
    list($dataString, $timestamp, $signature) = explode('.', $decoded);
    $expectedSignature = hash_hmac('sha256', $dataString . $timestamp, $secretKey);
    if ($signature !== $expectedSignature) {
        return false; // 签名不匹配
    }
    if (time() - $timestamp > $expire) {
        return false; // 已过期
    }
    $data = unserialize($dataString);
    return $data;
}

// 示例
$secretKey = 'your_secret_key';
$data = array('user_id' => 123);
$token = generateToken($data, $secretKey, 600); // 有效期 600 秒
echo $token;
// 验证
if ($data = verifyToken($token, $secretKey, 600)) {
    echo 'Token 验证成功: ' . print_r($data, true);
} else {
    echo 'Token 验证失败';
}
?>