數據庫 mysql 散列密碼

Question

所以我正在嘗試 hash 從登錄表單中的數據庫中獲取一些密碼，當我第一次嘗試登錄時，它使用數據庫中的密碼然后我 hash 使用 MD5 然后當我回到登錄頁面時，我想輸入以前使用的密碼讓我登錄，但它更改為 MD5 密碼。 有什么解決方案可以讓數據庫中的 MD5 和我使用第一個登錄的方式登錄嗎？在此先感謝（smecher.j 是一個為 0 的變量）

public void validateLogin(){
    DatabaseConnection connectNow = new DatabaseConnection();
    DatabaseConnection connectNow2 = new DatabaseConnection();

    Connection connectDB = connectNow.getConnection();
    Connection connectDB2 = connectNow2.getConnection();


    String verifyLogin = " SELECT count(1) FROM user_account WHERE username = '" + usernameTextField.getText()  + "' AND password ='" + enterPasswordField.getText() +"'";
    String insertFields3 = " UPDATE user_account SET password = MD5(password) WHERE username = '" + usernameTextField.getText() +"'";

    try{
        Statement statement  = connectDB.createStatement();
        Statement statement2  = connectDB2.createStatement();

        ResultSet queryResult = statement.executeQuery(verifyLogin);
        while(queryResult.next()){
            if(queryResult.getInt(1)==1){
                login1();
                if(smecher.j==0) {
                    statement2.executeUpdate(insertFields3);
                    smecher.j++;
                }

                text1=enterPasswordField.getText();
            }else{
                loginMessageLabel.setText("Invalid login, please try again");
            }

        }
        lol();
    }catch(Exception e){
        e.printStackTrace();
        e.getCause();
    }

}
public static String text1 = "";
public void lol() {
    Connection conn = null;
    Statement st = null;
    ResultSet rs = null;

    String dbUrl = "jdbc:mysql://localhost:3306/databaselol?autoReconnect=true&useSSL=false";
    String dbUsr = "root";
    String dbPass = "!Iloriana12";
    try {
        String sql = "SELECT password FROM user_account where username  = '" + usernameTextField.getText() + "'";
        Class.forName("com.mysql.cj.jdbc.Driver");
        conn = DriverManager.getConnection(dbUrl, dbUsr, dbPass);
        st = conn.createStatement();
        rs = st.executeQuery(sql);

        while(rs.next()){
            String value = rs.getString("password");
            text1 =value;
        }
        System.out.println(text1);

    }catch(Exception e){
        e.printStackTrace();
    }finally{
        try {
            rs.close();
        } catch (SQLException e) {
            e.printStackTrace();
        }
        try {
            st.close();
        } catch (SQLException e) {
            e.printStackTrace();
        }
        try {
            conn.close();
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}

Answer 1

保存密碼時，您應該將其加密保存，當您驗證密碼時，您應該驗證比較密碼的加密版本，如

String verifyLogin = " SELECT count(1) FROM user_account WHERE username = '" + usernameTextField.getText()  + "' AND password =MD5('" + enterPasswordField.getText() +"')";

String insertFields3 = " UPDATE user_account SET password = MD5('" + enterPasswordField.getText() + "') WHERE username = '" + usernameTextField.getText() +"'";