RSA解密-密钥不存在

Question

我正在尝试使用RSA加密和解密文件。加密工作正常。但我在解密时会出错。

错误是密钥不存在。

以下是错误：https://i.stack.imgur.com/Q4BH1.png

public byte[] RSA_Encrypt(byte[] bytesToBeEncrypted, byte[] passwordBytes, RSAParameters RSAKeyInfo)
{
    //initialze the byte arrays to the public key information.
    byte[] PublicKey = {214,46,220,83,160,73,40,39,201,155,19,202,3,11,191,178,56,
                           74,90,36,248,103,18,144,170,163,145,87,54,61,34,220,222,
                           207,137,149,173,14,92,120,206,222,158,28,40,24,30,16,175,
                           108,128,35,230,118,40,121,113,125,216,130,11,24,90,48,194,
                           240,105,44,76,34,57,249,228,125,80,38,9,136,29,117,207,139,
                           168,181,85,137,126,10,126,242,120,247,121,8,100,12,201,171,
                           38,226,193,180,190,117,177,87,143,242,213,11,44,180,113,93,
                           106,99,179,68,175,211,164,116,64,148,226,254,172,147};
    //Values to store encrypted symmetric keys.
    byte[] EncryptedSymmetricKey;
    byte[] EncryptedSymmetricIV;
    byte[] encryptedBytes = null;
    // Set your salt here, change it to meet your flavor:
    // The salt bytes must be at least 8 bytes.
    byte[] saltBytes = new byte[] { 1, 2, 3, 4, 5, 6, 7, 8 };
    using (MemoryStream ms = new MemoryStream())
    {
        using (RSACryptoServiceProvider RSA = new RSACryptoServiceProvider(_stBitov))
        {
            //Set RSAKeyInfo to the public key values.
            RSAKeyInfo.Modulus = PublicKey;
            //Import key parameters into RSA.
            RSA.ImportParameters(RSAKeyInfo);
            //Create a new instance of the RijndaelManaged class.
            RijndaelManaged RM = new RijndaelManaged();
            var key = new Rfc2898DeriveBytes(PublicKey, saltBytes, 1000);
            //Encrypt the symmetric key and IV.
            EncryptedSymmetricKey = RSA.Encrypt(RM.Key, false);
            EncryptedSymmetricIV = RSA.Encrypt(RM.IV, false);
            encryptedBytes = RSA.Encrypt(bytesToBeEncrypted, false); 
        }
    }
    return encryptedBytes;
}
RSAParameters _RSAKeyInfo;
public void EncryptFile()
{
    RSACryptoServiceProvider RSA = new RSACryptoServiceProvider();
    //Get an instance of RSAParameters from ExportParameters function.
    RSAParameters RSAKeyInfo = RSA.ExportParameters(false);
    _RSAKeyInfo = RSAKeyInfo;
    string path = ofd.FileName;
    if (File.Exists(path))
    {
        string dirPath = Path.GetDirectoryName(path);
        byte[] bytesToBeEncrypted = File.ReadAllBytes(path);
        byte[] passwordBytes = File.ReadAllBytes(dirPath + "/KEY_" + ofd.SafeFileName);
        byte[] bytesEncrypted = RSA_Encrypt(bytesToBeEncrypted, passwordBytes, RSAKeyInfo);
        string fileEncrypted = dirPath + "/ENCRYPTED_" + ofd.SafeFileName;
        File.WriteAllBytes(fileEncrypted, bytesEncrypted);
    }
}
private void button5_Click(object sender, EventArgs e)
{
    string path = ofd2.FileName;
    if (File.Exists(path))
    {
        DecryptFile();
        richTextBox4.Text = "Dekripcija uspesna";
    }
    else
    {
        richTextBox6.Text = "Datoteka ni dodana";
    }
} private void richTextBox4_TextChanged(object sender, EventArgs e) { }
public byte[] RSA_Decrypt(byte[] bytesToBeDecrypted, byte[] passwordBytes, RSAParameters RSAKeyInfo)
{
    byte[] PublicKey = {214,46,220,83,160,73,40,39,201,155,19,202,3,11,191,178,56,
                           74,90,36,248,103,18,144,170,163,145,87,54,61,34,220,222,
                           207,137,149,173,14,92,120,206,222,158,28,40,24,30,16,175,
                           108,128,35,230,118,40,121,113,125,216,130,11,24,90,48,194,
                           240,105,44,76,34,57,249,228,125,80,38,9,136,29,117,207,139,
                           168,181,85,137,126,10,126,242,120,247,121,8,100,12,201,171,
                           38,226,193,180,190,117,177,87,143,242,213,11,44,180,113,93,
                           106,99,179,68,175,211,164,116,64,148,226,254,172,147};
    //Values to store encrypted symmetric keys.
    byte[] EncryptedSymmetricKey;
    byte[] EncryptedSymmetricIV;
    byte[] decryptedBytes = null;
    // Set your salt here, change it to meet your flavor:
    // The salt bytes must be at least 8 bytes.
    byte[] saltBytes = new byte[] { 1, 2, 3, 4, 5, 6, 7, 8 };
    using (MemoryStream ms = new MemoryStream())
    {
        using (RSACryptoServiceProvider RSA = new RSACryptoServiceProvider(_stBitov))
        {
            //Set RSAKeyInfo to the public key values.
            RSAKeyInfo.Modulus = PublicKey;
            //Import key parameters into RSA.
            RSA.ImportParameters(RSAKeyInfo);
            //Create a new instance of the RijndaelManaged class.
            RijndaelManaged RM = new RijndaelManaged();
            //Encrypt the symmetric key and IV.
            EncryptedSymmetricKey = RSA.Encrypt(RM.Key, false);
            EncryptedSymmetricIV = RSA.Encrypt(RM.IV, false);
            decryptedBytes = RSA.Decrypt(bytesToBeDecrypted, false);
        }
    }
    return decryptedBytes;
}
public void DecryptFile()
{
    string path = ofd2.FileName;
    if (File.Exists(path))
    {
        string dirPath = Path.GetDirectoryName(path);
        byte[] bytesToBeDecrypted = File.ReadAllBytes(path);
        byte[] passwordBytes = File.ReadAllBytes(dirPath + "/KEY_" + ofd.SafeFileName);
        byte[] bytesDecrypted = RSA_Decrypt(bytesToBeDecrypted, passwordBytes, _RSAKeyInfo);
        string file = dirPath + "/DECRYPTED_" + ofd.SafeFileName;
        File.WriteAllBytes(file, bytesDecrypted);
    }
}

有人能告诉我该怎么做吗？解密会起作用的。

Answer 1

RSA是一种公钥密码学。这意味着您需要一个公钥来加密消息，需要一个私钥来解密消息。看起来您正在使用公钥进行加密和解密。你的私钥在哪里？

Answer 2

您似乎试图使用RSA+AES进行混合加密，但您忘记了实际使用AES加密明文，也忘记了使用RSA加密对称密钥。您还需要随机生成对称密钥，并且不应该从公钥派生，公钥应该是常量且public。

您在这里提出的错误是您的最小问题，但正如ElectroByt已经说过的，您需要使用私钥（RSACryptoServiceProvider#ExportParameters(true)）来使用RSA解密某些内容。在您的情况下，您需要使用RSA进行解密以获得对称密钥，然后使用它来解密对称密文以返回实际消息。