如何在C＃中加密/保護MS Access 2007數據庫文件？

Question

我有一個程序，可以使用簡單的數據庫密碼訪問/添加/刪除MS Access 2007文件中的條目。

但是我的目標是修改我的文件，以使其更加安全。 我想對我的文件進行加密，如果可能的話，可以使用用戶選擇的加密方式，並且只有在用戶提供正確的用戶名和密碼時，才可以訪問該文件。

我該怎么做？ 如何加密文件？ 我該如何做才能使用戶進行身份驗證？

請具體說明，並推薦使用假人示例：）

編輯：如果我將使用AES加密文件中的每個條目，那會更安全嗎？ 我應該這樣做並讓數據庫文件沒有密碼嗎？

這是我現在訪問文件的方式：

// May be public so we can display
// content of file from different forms.
public void DisplayFileContent(string filePath)
{
    // Creating an object allowing me connecting to the database.
    OleDbConnection objOleDbConnection = new OleDbConnection();
    // Creating command object.
    objOleDbConnection.ConnectionString =
        "Provider=Microsoft.ACE.OLEDB.12.0;" +
        "Data Source=" + filePath + ";" +
        "Persist Security Info=False;" +
        "Jet OLEDB:Database Password=" + storedAuth.Password + ";";
    OleDbCommand objOleDbCommand = new OleDbCommand();
    objOleDbCommand.Connection = objOleDbConnection;
    objOleDbCommand.CommandText = "Select * FROM PersonalData";

    // Create a data reader.
    OleDbDataReader readPersonalData;

    try
    {
        // Open database connection.
        objOleDbConnection.Open();

        // Associate data reader with the command.
        readPersonalData = objOleDbCommand.ExecuteReader();

        // Counting all entries.
        int countEntries = 0;

        // Clearing the textbox before proceeding.
        txtDisplay.Text = string.Empty;

        if (readPersonalData.HasRows)
        {
            while (readPersonalData.Read())
            {
                // Count all entries read from the reader.
                countEntries++;

                txtDisplay.Text += "=== Entry ID: " + readPersonalData.GetValue(0) + " ===" + Environment.NewLine;
                txtDisplay.Text += "Type: " + readPersonalData.GetValue(1) + Environment.NewLine;
                if (!readPersonalData.IsDBNull(2)) txtDisplay.Text += "URL: " + readPersonalData.GetValue(2) + Environment.NewLine;
                if (!readPersonalData.IsDBNull(3)) txtDisplay.Text += "Software Name: " + readPersonalData.GetValue(3) + Environment.NewLine;
                if (!readPersonalData.IsDBNull(4)) txtDisplay.Text += "Serial Code: " + readPersonalData.GetValue(4) + Environment.NewLine;
                if (!readPersonalData.IsDBNull(5)) txtDisplay.Text += "User Name: " + readPersonalData.GetValue(5) + Environment.NewLine;
                if (!readPersonalData.IsDBNull(6)) txtDisplay.Text += "Password: " + readPersonalData.GetValue(6) + Environment.NewLine;
                txtDisplay.Text += Environment.NewLine;
            }
        }
        else
        {
            txtDisplay.Text = "There is nothing to display! You must add something so I can display something here.";
        }

        // Displaying number of entries in the status bar.
        tsslStatus.Text = "A total of " + countEntries + " entries.";

        // Selecting 0 character to make sure text
        // isn't completly selected.
        txtDisplay.SelectionStart = 0;
    }

我的EncryptDecrypt.cs文件：

using System;
using System.IO;
using System.Text;
using System.Security.Cryptography;

namespace Password_Manager
{
    class EncryptDecrypt
    {
        string input, userName, password;

        RijndaelManaged Crypto = new RijndaelManaged();

        public EncryptDecrypt()
        {
        }

        public EncryptDecrypt(string input, string userName, string password)
        {
            this.input = input;
            this.userName = userName;
            this.password = password;
        }

        public string Encrypt(string PlainText, string pass, string usrName)
        {
            string HashAlgorithm = "SHA1"; 
            int PasswordIterations = 2;
            string InitialVector = "OFRna73m*aze01xY";
            int KeySize = 256;

            this.input = PlainText;

            if (string.IsNullOrEmpty(PlainText))
                return "";

            byte[] InitialVectorBytes = Encoding.ASCII.GetBytes(InitialVector);
            byte[] SaltValueBytes = Encoding.ASCII.GetBytes(usrName);
            byte[] PlainTextBytes = Encoding.UTF8.GetBytes(PlainText);

            PasswordDeriveBytes DerivedPassword = new PasswordDeriveBytes(pass, SaltValueBytes, HashAlgorithm, PasswordIterations);

            byte[] KeyBytes = DerivedPassword.GetBytes(KeySize / 8);

            RijndaelManaged SymmetricKey = new RijndaelManaged();

            SymmetricKey.Mode = CipherMode.CBC;

            byte[] CipherTextBytes = null;

            using (ICryptoTransform Encryptor = SymmetricKey.CreateEncryptor(KeyBytes, InitialVectorBytes))
            {
                using (MemoryStream MemStream = new MemoryStream())
                {
                    using (CryptoStream CryptoStream = new CryptoStream(MemStream, Encryptor, CryptoStreamMode.Write))
                    {
                        CryptoStream.Write(PlainTextBytes, 0, PlainTextBytes.Length);
                        CryptoStream.FlushFinalBlock();
                        CipherTextBytes = MemStream.ToArray();
                        MemStream.Close();
                        CryptoStream.Close();
                    }
                }
            }

            SymmetricKey.Clear();
            return Convert.ToBase64String(CipherTextBytes);
        }

        public string Decrypt(string CipherText, string pass, string usrName)
        {
            string HashAlgorithm = "SHA1"; 
            int PasswordIterations = 2;
            string InitialVector = "OFRna73m*aze01xY";
            int KeySize = 256;

             if (string.IsNullOrEmpty(CipherText))
                 return "";

             byte[] InitialVectorBytes = Encoding.ASCII.GetBytes(InitialVector);

             byte[] SaltValueBytes = Encoding.ASCII.GetBytes(usrName);
             byte[] CipherTextBytes = Convert.FromBase64String(CipherText);

             PasswordDeriveBytes DerivedPassword = new PasswordDeriveBytes(pass, SaltValueBytes, HashAlgorithm, PasswordIterations);

             byte[] KeyBytes = DerivedPassword.GetBytes(KeySize / 8);

             RijndaelManaged SymmetricKey = new RijndaelManaged();

             SymmetricKey.Mode = CipherMode.CBC;

             byte[] PlainTextBytes = new byte[CipherTextBytes.Length];

             int ByteCount = 0;

             using (ICryptoTransform Decryptor = SymmetricKey.CreateDecryptor(KeyBytes, InitialVectorBytes))
             {
                 using (MemoryStream MemStream = new MemoryStream(CipherTextBytes))
                 {

                     using (CryptoStream CryptoStream = new CryptoStream(MemStream, Decryptor, CryptoStreamMode.Read))
                     {
                         ByteCount = CryptoStream.Read(PlainTextBytes, 0, PlainTextBytes.Length);
                         MemStream.Close();
                         CryptoStream.Close();
                     }
                 }
             }

             SymmetricKey.Clear();
             return Encoding.UTF8.GetString(PlainTextBytes, 0, ByteCount);
         }
    }
}

Answer 1

絕對不要加密數據並將加密后的數據保存在數據庫中，您將最終遇到查詢，例如select field1, field2 from table where field1 = '$WDFV%$:@@{#%SAsdasdh#!fjdkj'字段必須是文本。 它大大削弱了使用RDBMS的目的。

訪問DB可以用密碼保護和加密的看到這這些在說明2010年，但也有一個鏈接到2007年。

但是，如果您將其用作winforms gui的后端，並且您不希望用戶在其中鍵入密碼，則必須將密碼存儲在某個地方，並且確定的用戶如果擁有密碼，則可以提取該密碼。知識。

如果保護敏感數據免受未授權用戶的侵擾是優先考慮的事情，那么訪問是一個壞選擇，如果現在在項目中更改時為時已晚，則以后不要使用它。