Создание парольной системы

Тема: Создание парольной системы.

Цель работы: изучение и реализация с помощью современной компьютерной техники средств парольной системы.

Индивидуальное задание:

№ вар	Хранение паролей	Генерация ключа БД
1	хеш	вручную

 

Листинг программы:

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Linq;

using System.Text;

using System.Windows.Forms;

using System.Security.Cryptography;

using System.IO;

using System.Data.OleDb;

 

namespace md4

{

    public partial class MainForm : Form

    {

        public MainForm(){

            InitializeComponent();

            textBox5.PasswordChar = '*';

        }

 

        public string MD4(string content){

            Chilkat.Crypt2 crypt = new Chilkat.Crypt2();

            bool success;

            success = crypt.UnlockComponent("30-day trial");

            if (success!=true){

                MessageBox.Show(crypt.LastErrorText);

                return null;

            }

            crypt.EncodingMode = "hex";

            crypt.HashAlgorithm = "md4";

            string hashStr;

            hashStr = crypt.HashStringENC(content);

            return hashStr;

        }

 

        private void button1_Click_1(object sender, EventArgs e)

        {

            String Login = textBox1.Text;

            String Password1 = textBox2.Text;

            String Password2 = textBox3.Text;

            bool flag=true;

            string connectionString = @"provider=Microsoft.Jet.OLEDB.4.0; data source=DataBase.mdb";

            OleDbConnection myOleDbConnection = new OleDbConnection(connectionString);

            myOleDbConnection.Open();

            OleDbDataAdapter orderAdapter = new OleDbDataAdapter("SELECT * FROM MyTable ORDER BY ID", myOleDbConnection);

            if(Login=="") { MessageBox.Show("Поле Логин пустое!"); flag = false; }

            if(Password1=="") { MessageBox.Show("Поле Пароль пустое!"); flag = false; }

            if(Password1!= Password2){ MessageBox.Show("Пароли не совпадают!"); flag=false;}

            if(Password1.Length<5) { MessageBox.Show("Ошибка! Пароль <5!"); flag=false;}

            OleDbCommand myOleDbCommand = myOleDbConnection.CreateCommand();

            myOleDbCommand.CommandText="SELECT * FROM MyTable ORDER BY ID";

            OleDbDataReader myOleDbDataReader = myOleDbCommand.ExecuteReader();

            if(myOleDbDataReader.HasRows){

              while (myOleDbDataReader.Read()){

                if(Convert.ToString(myOleDbDataReader["Login"])==Login){ MessageBox.Show("Такой пользователь уже сужествует"); flag=false;}

              }

             }

            if(flag==true){

                String str = "INSERT INTO MyTable(Login,Pass)VALUES('" + Login + "','" + MD4(Password1) + "');";

                OleDbCommand command = new OleDbCommand(str, myOleDbConnection);

                orderAdapter.InsertCommand = command;

                orderAdapter.InsertCommand.ExecuteNonQuery();

                myOleDbConnection.Close();

            }

        }

 

        private void button2_Click_1(object sender, EventArgs e){

            String Login = textBox4.Text;

            String Password = textBox5.Text;

            bool flag = false;

            string connectionString = @"provider=Microsoft.Jet.OLEDB.4.0; data source=DataBase.mdb";

            OleDbConnection myOleDbConnection = new OleDbConnection(connectionString);

            myOleDbConnection.Open();

            OleDbCommand myOleDbCommand = myOleDbConnection.CreateCommand();

            myOleDbCommand.CommandText = "SELECT * FROM MyTable ORDER BY ID";

            OleDbDataReader myOleDbDataReader = myOleDbCommand.ExecuteReader();

            if (myOleDbDataReader.HasRows){

                while (myOleDbDataReader.Read()){

                    if (Convert.ToString(myOleDbDataReader["Login"])==Login&&Convert.ToString(myOleDbDataReader["Pass"])==MD4(Password)) flag = true;

                }

            }

            if (flag == true) MessageBox.Show("Вход выполнен успешно!");

            else MessageBox.Show("Зарегистрируйтесь!");

        }

 

        private void Form1_Load(object sender, EventArgs e){}

 

    }

}

 

 

Вывод: в ходе выполнения лабораторной работы изучил и реализовал с помощью современной компьютерной техники парольной системы.