VERAG_Homepage/login/ForgotPW.aspx.vb

Imports System.Net
Imports System.Net.Mail
Imports System.Drawing
Imports System.Configuration
Imports System.Data.SqlClient
Imports System.Data

Partial Class login_ForgotPW
    Inherits System.Web.UI.Page

    Protected Sub btn_Back_Click(sender As Object, e As EventArgs)
        Response.Redirect("login/login_FLEX.aspx")
    End Sub

    Protected Sub btn_Send_Click(sender As Object, e As EventArgs)
        Dim username As String
        Dim password As String
        Dim email As String
        Dim tokenname As String
        valreqtxtEmail.Validate()
        If valreqtxtEmail.IsValid() = True Then
            username = txt_Username.Text
            password = String.Empty
            email = txtEmail.Text
            tokenname = String.Empty
        End If
        'cDBFunctions.GetNewOpenConnection()
        Dim ConnectionString = String.Empty
        If HttpContext.Current.Request.ServerVariables("SERVER_NAME") = "localhost" Then
            'ConnectionString = "Server=DEVELOPER\DEVSQL;Database=VERAG_HOMEPAGE;Uid=sa;Pwd=BmWr501956"
            ConnectionString = "Server=DEVELOPER\DEVSQL;Database=VERAG_HOMEPAGE;Uid=AppUser;Pwd=yp/THDd?xM+pZ$;"
        Else
            ConnectionString = "Server=DEVELOPER.verag.ost.dmn\DEVSQL;Database=VERAG_HOMEPAGE;Uid=AppUser;Pwd=yp/THDd?xM+pZ$;"
            'ConnectionString = "Server=db593295684.db.1and1.com;Database=db593295684;Uid=dbo593295684;Pwd=atilla#2;"
        End If
        ' Dim constr As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString
        Using con As New SqlConnection(ConnectionString)
            ' Using cmd As New SqlCommand("Validate_User")
            Using cmd As New SqlCommand("SELECT Username,Password FROM [VERAG_HOMEPAGE].[dbo].[Users] WHERE Username=@Username")
                ' cmd.CommandType = CommandType.StoredProcedure
                cmd.Parameters.AddWithValue("@Username", username)
                cmd.Connection = con
                con.Open()
                'userId = Convert.ToInt32(cmd.ExecuteScalar())
                Dim dr As SqlDataReader = cmd.ExecuteReader()
                If dr.Read() Then
                    username = dr("Username").ToString()
                    password = dr("Password").ToString()
                    Try
                        regexval_txt_Email.Validate()
                    Catch ex As Exception
                        Dim Msg, Style, Title As String
                        Msg = "E-Mail Prüfung fehlgeschlagen!" & vbCrLf + "Bitte erneut versuchen!"
                        Style = vbRetry + vbExclamation + vbDefaultButton1
                        Title = "Fehler bei E-Mail Authentifizierung!"
                        MsgBox(Msg, Style, Title)
                        If MsgBox(Msg, Style, Title).Yes Then
                            txtEmail.Text = String.Empty
                            txtEmail.Focus()
                        ElseIf MsgBox(Msg, Style, Title).No Then
                        End If
                    End Try
                End If
            End Using
            con.Close()
        End Using
        tokenname = genToken(username, password, email)
        Session.Add("TokenforEmail", tokenname)
        If SendEmail(username, password, email, tokenname) = True Then
            'password = RandomString(New Random, 10)
            If (getDateoftoken(tokenname) = True) Then
                Dim msgboxstyle = vbDefaultButton1 + vbOK
                'MsgBox(tokenname, msgboxstyle)
                MsgBox("Token erfolgreich generiert.")
            Else
                MsgBox("Token ist nicht mehr gültig! Es wird ein neuer generiert!")
                tokenname = genToken(username, password, email)
            End If
            'SendEmail(username, password, email)
            MsgBox("Mail would be sent successfully!")
            lblMessage.ForeColor = Color.Green
            lblMessage.Text = "Passwort wurde erfolgreich an die angegebene E-Mail Adresse gesendet."
        ElseIf SendEmail(username, password, email, tokenname) = False Then
            MsgBox("Mail would not be sent successfully!")
            lblMessage.ForeColor = Color.Red
            lblMessage.Text = "Diese E-Mail ist nicht in unserer Datenbank vorhanden."
        End If
    End Sub

    'Function RandomString(r As Random, max As Integer) As String
    'Dim s As String = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789!§$%&/?="
    'Dim sb As New StringBuilder
    'Dim cnt As Integer = r.Next(4, max)
    'For i As Integer = 1 To cnt
    'Dim idx As Integer = r.Next(0, s.Length)
    '       sb.Append(s.Substring(idx, 1))
    'Next
    'Return sb.ToString()
    'End Function

    Function SendEmail(username As String, password As String, email As String, tokenname As String) As Boolean
        Dim getdomianenvironment As String = String.Empty
        Dim pagename As String = String.Empty
        Dim ServPort As String = String.Empty
        If HttpContext.Current.Request.ServerVariables("SERVER_NAME") = "localhost" Then
            getdomianenvironment = HttpContext.Current.Request.ServerVariables("SERVER_NAME")
            ServPort = ":" + Request.ServerVariables("SERVER_PORT")
            'pagename = Request.ServerVariables("SCRIPT_NAME")
        ElseIf HttpContext.Current.Request.ServerVariables("SERVER_NAME") = Not "localhost" Then
            getdomianenvironment = HttpContext.Current.Request.ServerVariables("SERVER_NAME")
            ServPort = String.Empty
            'pagename = Request.ServerVariables("SCRIPT_NAME")
        End If
        'Dim pg As String = Request.ServerVariables("URL")
        'MsgBox("/" + ServPort + Request.ServerVariables("URL"))
        Dim mailto As String = email
        Dim Betreff As String = "Passwort reset"
        Dim htmlbody = String.Format("Sehr geehrte/r {0},<br /><br /> Bitte dem Link zum Zurücksetzen des Passwortes folgen:<br /><br /><br />.<br />" + Environment.NewLine + "<a runat=" + "server" + " href=http://" + getdomianenvironment + ServPort + "/login/ChangePW.aspx?Par1=" + VERAG_PROG_ALLGEMEIN.cCryptography.Encrypt(tokenname) + ">Link</a>" + Environment.NewLine + "<br />Mit freundlichen Grüßen,", username, password)
        Try
            Dim tokennametemp = genToken(username, password, email)
            'Dim Strtemp = Session.Keys.Item("urltochangepw")
            If getDateoftoken(tokennametemp) = True Then
                '  Dim attachment As Attachment = New Attachment(File.OpenRead(excel), "Kundenliste.xlsx")
                '  Msg.Attachments.Add(attachment)
                VERAG_PROG_ALLGEMEIN.cProgramFunctions.sendMail(mailto, Betreff, htmlbody)
                MsgBox("SENT")
                Return True
            Else
                MsgBox("Error02: Mail not delivered!" & vbCrLf & "Neuer Token wird generiert.")
                tokennametemp = genToken(username, password, email)
                VERAG_PROG_ALLGEMEIN.cProgramFunctions.sendMail(mailto, Betreff, htmlbody, tokenname)
                Return False
            End If
        Catch ex As Exception
            MsgBox(Err.Number & ex.Message & ex.StackTrace.ToString) 'Falls ein Fehler auftritt wird eine MsgBox angezeigt
        End Try
        Return False
    End Function

    Function genToken(username As String, password As String, email As String) As String
        Dim time() As Byte = BitConverter.GetBytes(DateTime.UtcNow.ToBinary())
        Dim Key() As Byte = Guid.NewGuid().ToByteArray()
        Dim token As String
        Try
            token = Convert.ToBase64String(time.Concat(Key).ToArray())
            Return token
        Catch Ex As Exception
            Dim Msg, Style, Title As String
            Msg = "Tokengenerierung fehlgeschlagen!" & vbCrLf & "Eine E-Mail wurde erneut an " + email + " zugesendet."
            Style = vbRetry + vbExclamation + vbDefaultButton1
            Title = "Fehler bei Token-Generierung"
            MsgBox(Msg, Style, Title)

            If MsgBox(Msg, Style, Title).Retry Then
                genToken(username, password, email)
                If SendEmail(username, password, email, token) = False Then
                    MsgBox("Email konnte wegen eines internen Verschlüsselungsfehlers nicht gesendet werden.", vbOK + vbInformation + vbDefaultButton1, "Tokengenerierung-Fehler")
                Else
                    MsgBox("Email wurde erfolgreich gesendet." & vbCr & "Bitte Postfach überprüfen!", vbOK + vbInformation + vbDefaultButton1, "Tokengenerierung erfolgreich!")
                End If
            Else
                MsgBox("Tokengenerierung nicht erfolgreich." & vbCrLf & "In 5 Sekunden nochmal versuchen!")
                Dim jetzt As DateTime = DateTime.UtcNow
                Dim wenn As DateTime = DateTime.UtcNow.AddSeconds(-5)

                If jetzt < wenn Then
                    Return "NotYet"
                Else
                    token = Convert.ToBase64String(time.Concat(Key).ToArray())
                    Return token
                End If
            End If
        End Try
    End Function

    Function getDateoftoken(tokenname As String) As Boolean
        Dim data() As Byte = Convert.FromBase64String(tokenname)
        Dim wenn As DateTime = DateTime.FromBinary(BitConverter.ToInt64(data, 0))
        If wenn < DateTime.UtcNow.AddMinutes(-30) Then
            tokenname = String.Empty
            MsgBox("Token nicht gefunden oder zu alt!" + Environment.NewLine + "Bitte erneut Mail senden!")
            Return False
        ElseIf tokenname = "NotYet" Then
            Return False
        ElseIf tokenname = "Error04" Then
            Return False
        Else
            Return True
        End If
    End Function
End Class