BCrypt根据数据库中的密码验证密码

Question

I am trying to verify a hashed password in my database which has been hashed with BCrypt.

I have two web forms, a login page and registration page.

In the registration page i create the hash, verify the hash and insert it into the database. Works fine.

In the login page i select the hashed password from the database and compare it with the submitted password from the text box.

I seem to be having trouble when verifying the hash in the database against the submitted password, i don't know what is going wrong.

Here is the registration page code:

protected void registerbutton_Click(object sender, EventArgs e)
    {
        string myPassword = passwordtextbox.Text;
        string mySalt = BCryptHelper.GenerateSalt();     
        string myHash = BCryptHelper.HashPassword(myPassword, mySalt);
        bool doesPasswordMatch = BCryptHelper.CheckPassword(myPassword, myHash);


        if (doesPasswordMatch == true)
        {
                using (SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["DefaultConnection"].ConnectionString))
                using (SqlCommand cmd = new SqlCommand("INSERT INTO dbo.Users (Username, Password, FirstName, LastName) VALUES (@username, @password, @firstname, @lastname)", conn))
                {
                    cmd.Parameters.Add("@username", SqlDbType.NVarChar).Value = usernametextbox.Text;
                    cmd.Parameters.Add("@password", SqlDbType.Char).Value = myHash;
                    cmd.Parameters.Add("@firstname", SqlDbType.NVarChar).Value = firstnametextbox.Text;
                    cmd.Parameters.Add("@lastname", SqlDbType.NVarChar).Value = lastnametextbox.Text;

                    conn.Open();
                    cmd.ExecuteNonQuery();
                    conn.Close();

                    registerlabel3.Text = myHash;


            }
        }
        else
        {
            registerlabel3.Text = "Error";
        }
    }

Here is the login page code:

protected void loginbutton_Click(object sender, EventArgs e)
    {
        const string query = "SELECT Username, Password FROM dbo.Users WHERE Username = @username";

        using (SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["DefaultConnection"].ConnectionString))
        using (SqlCommand cmd = new SqlCommand(query, conn))
        {
            cmd.Parameters.Add("@username", SqlDbType.NVarChar).Value = usernametextbox.Text;
            conn.Open();

            //string hashedPassword = BCrypt.Net.BCrypt.HashPassword(passwordtextbox.Text);

            using (SqlDataReader reader = cmd.ExecuteReader())
            {
                while (reader.Read())
                {
                    var passwordInDb = reader.GetString(1);

                    Label3.Text = "submitted = " + passwordtextbox.Text;
                    Label4.Text = "database hash = " + passwordInDb;

                    if(BCryptHelper.CheckPassword(passwordtextbox.Text, reader.GetString(1)))
                    {
                        //login
                        loginlabel.Text = "Success";
                    }
                    else
                    {
                        loginlabel.Text = "Error";
                    }




                }
            }
        }
    }

Help and Feedback is appreciated.

Answer 1

写入数据库时​​，请尝试：

protected void registerbutton_Click(object sender, EventArgs e) { .... cmd.Parameters.Add("@password", SqlDbType.NVarChar).Value = myHash; .... }

Answer 2

Set the database field to CHAR(60)

I set my database field where the hashed password is stored to CHAR(60) and now it works.

Why it has to be specifically CHAR(60), i don't know, but it works.

Would be nice if this could be explained.