我如何解码vb.net中的laravel加密字符串

Question

我似乎找不到有关此问题的有效答案...

我正在使用内置的 crypt :: gencrypt（） helper函数并传递简单字符串值（假设'abcde'出于本示例的目的） 如果我能提供帮助，我不想在Laravel中安装任何第三方库。我也有我的laravel app_key ，它是一个以 base64：开始的字符串值，但我不确定它的何处。

这为我生成了一个加密的字符串，我将其传递给VB.NET应用程序。 我无法锻炼如何简单地解码我的应用程序中的加密字符串，以删除'abcde''的原始密码。

我尝试了许多可以在线找到的示例，但是我一直遇到有关“不是有效键”或“不是有效的base64字符串”等的错误

。在.net？

我能做到的最好的是将加密的字符串分解为 iv ， value 和 mac ，但我似乎无法进一步。

任何帮助将不胜感激。

Answer 1

文档

加密您可以使用加密助手加密值的值。
所有加密值均使用 openssl 进行加密
AES-256-CBC 密码。此外，所有加密值均使用消息身份验证代码（MAC）签名以检测任何修改
到加密字符串

开始开始，让我们看“内部” crypt file vendor/laravel/framework/src/src/inluminate/concryption/encrypter.php

class Encrypter implements EncrypterContract, StringEncrypter
{
     /**
     * The encryption key.
     *
     * @var string
     */
    protected $key;

    /**
     * The algorithm used for encryption.
     *
     * @var string
     */
    protected $cipher;
     /**
     * Create a new encrypter instance.
     *
     * @param  string  $key
     * @param  string  $cipher
     * @return void
     *
     * @throws \RuntimeException
     */
    public function __construct($key, $cipher = 'aes-128-cbc')
    {
        $key = (string) $key;

        if (! static::supported($key, $cipher)) {
            $ciphers = implode(', ', array_keys(self::$supportedCiphers));

            throw new RuntimeException("Unsupported cipher or incorrect key length. Supported ciphers are: {$ciphers}.");
        }

        $this->key = $key;
        $this->cipher = $cipher;
    }
...
}

param> param 键/code> in __构造方法是base64解码值（在调用中更深的地方）app_key的 .env .env 之后的文件：

//APP_KEY=base64:uk1lwVRJIWHaMkiGRcFIzAcTzzGaauYtMSy4L+0ViDk=
$key = base64decode('uk1lwVRJIWHaMkiGRcFIzAcTzzGaauYtMSy4L+0ViDk=');
// and then it passes into __construct method

cipher < /code>在 AES-256-CBC rel =“ nofollow noreferrer”> docs （需要提及，该部分在所有现有版本的Laravel（包括V9）（当时）中保持不变，

请接下来寻找加密以

/**
     * Encrypt the given value.
     *
     * @param  mixed  $value
     * @param  bool  $serialize
     * @return string
     *
     * @throws \Illuminate\Contracts\Encryption\EncryptException
     */
    public function encrypt($value, $serialize = true)
    {
        // openssl_cipher_iv_length for initialization vector (IV) is 16 bytes for AES-256-CBC
        $iv = random_bytes(openssl_cipher_iv_length(strtolower($this->cipher)));
        // not used in our case
        $tag = '';
        
        $value = self::$supportedCiphers[strtolower($this->cipher)]['aead']
            ? \openssl_encrypt(
                $serialize ? serialize($value) : $value,
                strtolower($this->cipher), $this->key, 0, $iv, $tag
            )
            : \openssl_encrypt(
                $serialize ? serialize($value) : $value,
                strtolower($this->cipher), $this->key, 0, $iv
            );

        if ($value === false) {
            throw new EncryptException('Could not encrypt the data.');
        }

        $iv = base64_encode($iv);
        $tag = base64_encode($tag);
        // not used in our case
        $mac = self::$supportedCiphers[strtolower($this->cipher)]['aead']
            ? '' // For AEAD-algoritms, the tag / MAC is returned by openssl_encrypt...
            : $this->hash($iv, $value);
        // here is a tricky part, pay attention that we didn't encode $value in base64
        $json = json_encode(compact('iv', 'value', 'mac', 'tag'), JSON_UNESCAPED_SLASHES);

        if (json_last_error() !== JSON_ERROR_NONE) {
            throw new EncryptException('Could not encrypt the data.');
        }

        return base64_encode($json);
    }

在此处 获取操作订单我们有基本64编码的JSON数组，它具有base64编码 iv 和未手动编码 value

---

c＃part（解析JSON newtonsoft json ，.net472）

来自 Microsoft docs （此部分保持'as'是'，因为

static string DecryptStringFromBytes_Aes(byte[] cipherText, byte[] Key, byte[] IV)
        {
            // Check arguments.
            if (cipherText == null || cipherText.Length <= 0)
                throw new ArgumentNullException("cipherText");
            if (Key == null || Key.Length <= 0)
                throw new ArgumentNullException("Key");
            if (IV == null || IV.Length <= 0)
                throw new ArgumentNullException("IV");

            // Declare the string used to hold
            // the decrypted text.
            string plaintext = null;

            // Create an Aes object
            // with the specified key and IV.
            using (Aes aesAlg = Aes.Create())
            {
                aesAlg.Mode = CipherMode.CBC; // this is defaul value
                aesAlg.Padding = PaddingMode.PKCS7; // this is default value                

                aesAlg.Key = Key;
                aesAlg.IV = IV;
                
                // Create a decryptor to perform the stream transform.
                ICryptoTransform decryptor = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV);

                // Create the streams used for decryption.
                using (MemoryStream msDecrypt = new MemoryStream(cipherText))
                {
                    using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
                    {

                        using (StreamReader srDecrypt = new StreamReader(csDecrypt))
                        {
                            // Read the decrypted bytes from the decrypting stream
                            // and place them in a string.                            
                            plaintext = srDecrypt.ReadToEnd();
                        }
                    }
                }
            }

            return plaintext;
        }

​要绑所有这些东西，

        /// <summary>
        /// 
        /// </summary>
        /// <param name="key">app_key from .env after :</param>
        /// <param name="encodedText">result of Crypt::encrypt($value) or Crypt::encryptString($value) methods</param>
        /// <returns>decoded string</returns>
        private string parse(string key, string encodedText)
        {   
            // getting bytes from app_key same as in laravel
            byte[] keyBytes = Convert.FromBase64String(key);             
            
            // going back step by step                     
            // getting from base64 json and getting array of values 
            byte[] dataBytes = Convert.FromBase64String(encodedText);
            string base64decodedData = Encoding.UTF8.GetString(dataBytes);

            var parts = JsonConvert.DeserializeObject<Dictionary<string, string>>(base64decodedData);
            // iv in laravel was encoded with base64 before packing, so undo
            byte[] iv = Convert.FromBase64String(parts["iv"]);            
            
            // and here is the tricky part i've mentioned in encryption method
            // in laravel docs - there were no manual encoding $value to base64
            // but to get valid bytes for decryption we need to treat parts["value"] as 
            // it was encoded
            byte[] valueBytes = Convert.FromBase64String(parts["value"]);

            return DecryptStringFromBytes_Aes(valueBytes, keyBytes, iv);

        }

---

需要说我并没有很努力地挖掘加密算法，甚至没有尝试此代码可以处理使用 $ mac param的algos，因此，如果某人想要要添加更多信息 - 欢迎您