Click here to Skip to main content
14,578,769 members

Application Cleaner (NSA Killer)

Rate this:
4.88 (23 votes)
Please Sign up or sign in to vote.
4.88 (23 votes)
16 Apr 2015CPOL
How to use Filestream and Fileinfo to edit .exe or .dll files


Application Cleaner is a simple concept that performs a search and replace on program code/data to remove any spyware URLs within program code to stop programs such as web-browsers from calling home and was written in VS2010 using C# and makes extensive use of the System.IO.Filestream and System.IO.Fileinfo classes to open, read and then edit program code or data.

Threading for the File Scanner and Form

The program works by starting a new thread that calls the code that is shown below that is a recursive function used to iterate the directory tree of the folders and calls the function "ScanFolderFiles" with a Directoryinfo object to perform the processing.

private static void ScanFolders(DirectoryInfo DInfo)
        {//Recursive function used to scan sub-folders if "RootFolderOnly" is not set to true
            if (RootFolderOnly) return;//Nope we don't need to index sub-folders this time
            foreach (DirectoryInfo SubDIofo in DInfo.GetDirectories())

  private static void ScanFolderFiles(DirectoryInfo DInfo)
        {//Scan for files and then call ReadFile to index links
            foreach (FileInfo FInfo in DInfo.GetFiles())
                if (!Running) return;
                while (Paused) { Thread.Sleep(2000); }
                if (!FInfo.Name.EndsWith(".backup"))
                    ReadFile(FInfo);  //Might add a load more links to be displayed
                    DisplayNewLinks(); //Now display any new links we found
           );//We have done with the folder

The user is given the option of pausing or terminating the scanners thread by setting the static bool values of Running or Pause to true or false.

ReadFile opens up the file using a file stream that reads all of the file into a byte[] array that is then chopped up into a byte array of 10k chunks so that URLs can be searched for and added to a links dictionary with the Links.Displayed value set as false and then DisplayNewLinks() is called.

private static void DisplayNewLinks()
        {//Any link in our dictionary of links that have not been displayed is saved as a string array
            foreach (Link L in Scanner.Links.Values)
                if (!L.Displayed)
                {//Show any new links in the list-view
                    L.Displayed = true;//Only show the link once
                    AddNewFind(L.Finfo.Name, L.LinkText, L.Find, 
                    L.ChunkCount,L.Start , L.ImageIndex, L.Finfo.Directory.FullName);

Note that all of the above work was completed using the Scanners own thread and that the "AddNewFind" function locks a "NewFind" string before appending the data past in as '¬' separated values to the end of the string so that a form timer can later call Scanner.GetListViewItems() that again locks the "NewFind" string and then proceeds to convert the string into ListViewItems that are then appended to the forms main ListView.

public static Dictionary<int, ListViewItem> GetListViewItems()
{//Called on the UI thread and returns new data to be displayed in the list-view
    Dictionary<int, ListViewItem> LVItems = new Dictionary<int, ListViewItem>();
    string[] Items = null;
    lock (NewFind)//We lock it here so we don't get a threading error.
        Items = NewFind.Replace(Environment.NewLine,
        "~").Split('~');//Take a quick copy
        NewFind = "";
        MessageCount = 0;
    foreach (string Item in Items)
    {//Split the string and covert the data to list-view-items ready to add to the list-view
        string[] Data = Item.Split('¬');
        if (Data.Length > 2)
            int Num = 0;
            int.TryParse(Data[0], out Num);
            ListViewItem LVI = new ListViewItem(Data);//Conver an array to values
            if (Num > 0)
                LVItems.Add(Num, LVI);
    return LVItems;

Reading files and then processing the data is very CPU intensive and without any Thread.Sleeps() in the above code the form timer would hardly get a chance to fire and the form would freeze up so depending on how many links are waiting to be displayed, the main Scanner thread sleeps now and then to give the U.I a chance to catch up and that concludes our part on Threading.

Output Display and Sorting the List-view Results

Image 1

Application cleaner uses color coded flags in the list-view to denote the type of URL found so that the user can perform a manual search and replace or double-click items in the list for auto-replace to do the work but I soon discovered that your average web-browser contains about 5000 URLs embedded in the program code, DLLs and data with one well known web-browser having over 20,000 URLs ( I will come back to this later) so the rush was on to sort the list-view results.

The code that was added to the form to sort the list view is shown below and you should note from the picture above that columns [0], [4] and [5] are all numeric values and are used in the code below.

private SortOrder OrderBy = SortOrder.Ascending;
       private void LVScanner_ColumnClick(object sender, ColumnClickEventArgs e)
       {//Sort the list-view but note that this will slow the program down when new rows are added
           bool IsNumber = false;
           if (OrderBy == SortOrder.Ascending) OrderBy = SortOrder.Descending;
           else OrderBy = SortOrder.Ascending;
           int Col = int.Parse(e.Column.ToString());
           if (Col > 6) return;//We don't have a column number 7
           if (Col == 0 || Col == 4 || Col == 5) IsNumber = true;//We need to tell our
           //"ListViewItemComparer" to sort the data as a number and not a string
           this.LVScanner.ListViewItemSorter = new ListViewItemComparer
           (e.Column, OrderBy, IsNumber);//The class was easy to write and is worth a look

Our code for the ListViewItemComparer class is shown below and it could be expanded to pre-scan some of the column data to decide if the column is numeric or not but all that takes time and code so I decide to simply hardcode the values into the code for now.

using System;
using System.Collections;
using System.Windows.Forms;
using System.Text;
public class ListViewItemComparer : IComparer
{//This class is used so that the listview can be sorted by clicking on the columns 
    private int col;
    private SortOrder order;
    private bool IsNumber = false;
    public ListViewItemComparer()
        col = 0;
        order = SortOrder.Ascending;
    public ListViewItemComparer(int column, SortOrder order, bool isNumber)
        col = column;
        this.order = order;
        this.IsNumber = isNumber;
    public int SafeGetInt(string Text)
    {//This also sorts ip-addresses based on the first digit or double numbers
        Text = Text.Trim();
        int Value = 0;
        int End = Text.IndexOf(".");
        if (End > -1) Text = Text.Substring(0, End);
        End = Text.IndexOf(" ");
        if (End > -1) Text = Text.Substring(0, End).Trim();
        End = Text.IndexOf("/");
        if (End > -1) Text = Text.Substring(0, End);
        int.TryParse(Text, out Value);
        return Value;
     public int CompareNumber(object x, object y)
        int returnVal = -1;
        int IntX = SafeGetInt(((ListViewItem)x).SubItems[col].Text);
        int IntY = SafeGetInt(((ListViewItem)y).SubItems[col].Text);
        if (IntX > IntY)
            returnVal = 1;
        if (order == SortOrder.Descending)
            // Invert the value returned by String.Compare.
            returnVal *= -1;
        return returnVal;
    public int Compare(object x, object y)
        int returnVal = -1;
        if (this.IsNumber) return CompareNumber(x, y);
        returnVal = String.Compare(((ListViewItem)x).SubItems[col].Text,
        // Determine whether the sort order is descending.
        if (order == SortOrder.Descending)
            // Invert the value returned by String.Compare.
            returnVal *= -1;
        return returnVal;

20,000 URLs Hidden in a Browser, Are You Serious!

Well yes and that's without the cached history or cookies and one of the reasons this number is so high is because when a program is compiled that uses embedded Photoshop images then each image will contain a URL pointing to and then you have XML schemas all over the place plus hundreds of URLs needed for SSL-Certificates from Verisign & Co but even then it still leaves a lot.

With so much data, it became necessary to remove this common type of data from the results so that users could see the wood through the trees and the way that I decided to do this was to first add the option of hiding SSL-Certificate results and to then make use of profile that could be loaded by the user to filter the results for a particular type of data.

Image 2

As you can see, our data is now sorted by state in the above picture and if you look close at the top two rows, you will see that Application Cleaner also manages to search the program code and data for anything that looks like an IP-Address but sometimes makes a mistake with four digit version numbers that look the same as an IP-Address.

Scanning for embed IP-Addresses is nice to have because viruses often use these addresses to call home and this program makes them easy to spot but many browsers also hardcode Googles DNS-Server IP address of into the browser so that these browsers can bypass your local security if they are being blocked by URLs in the firewall or the DNS-Server/Virus blocker is trying to block the requests.

The project uses profile files that configure the scanner for a particular type of data to be indexed and contains a list of values to be automatically searched and replace and the function used to load profiles is shown below and works a bit like the old Windows .ini files with a bit of a twist and for me the Windows registry with its 400,000 folders is getting a bit full and far too many programs get to read its contents to generate fingerprints.

public static string LoadSettingFromFile(string Key, string Default, string Profile)
{//Load a string from the file system if we can find the file or
// just create it and if the string key is not in the file than
 //add it with a default value
      string FileName = Environment.CurrentDirectory + "\\" + Profile;
      if (!File.Exists(FileName))
      {//We need to add a new profile file
          File.WriteAllText(FileName, Key + " " + Default + Environment.NewLine);
          return Default;
      string[] Lines = File.ReadAllLines(FileName);
      foreach (string Line in Lines)
      {//Read all the lines in the file to find our key
          if (Line.ToLower().Trim().StartsWith(Key.ToLower()))
              return Line.ChopOffBefore(Key).Trim();//Yes found the value so return it
      StreamWriter SW = File.AppendText(FileName);//We need to add the new key and default to the profile file
      SW.WriteLine(Key + " " + Default);
      return Default;

Objectives and Achievements

I use a proxy server and a DNS-Server to block spyware on our LAN and I was getting a bit tired of seeing the proxy server logs filling up over night when no one was even browsing and I also knew that even Microsoft was bypassing the Windows proxy server setting to try to call home using encrypted SSL traffic because my firewall as a last line of defence was blocking these malicious requests from getting out so I decide to tackle this problem at source by editing the machine code of the programs that were behind the attempts to use backdoors.

It now takes me about half an hour to doctor most browsers using this program so that they are unable to upload super cookies that get installed in browsers when you have to run one of them "Install" programs that uses a downloader to install a browser that makes a profit by leaching and then selling your private data to the highest bidder.


This is my second attempt with this little program and my mistake in the first version was not to index the program contents but to instead do a quick search and replace in one go when the file was being read but this proved to be a bit slow when having to re-scan the data each time a search and replace was done but that has been fixed now but it would be nice to somehow make it even fast since it can take five minutes to scan the index for a project.

Replacing URLs strings in sections of machine code was easy so long as the length of the text being replaced is kept the same to ensure that machine code jumps in the code all remain the same and for this reason the program will reject any attempt to replace "" with "abc,com" but this is not the case with XML type data so it would be nice to have find a fix for this but it would need to take into account that the last-write date for the files must be preserved because some programs check for this.

As you can see, I am useless at documentation and the help text for the program needs rewriting from scratch by anyone but you will find the full source code for the project is well commented and you are free to download a copy by clicking the link at the top of the page and to make the project your own.

Dr Gadgit


This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)


About the Author

Dr Gadgit
United Kingdom United Kingdom
Old dog that is tired of learning new tricks when the new dish they are cooking never tastes quite so good as the old one.

Comments and Discussions

GeneralMy vote of 5 Pin
Agent__0077-May-15 18:00
professionalAgent__0077-May-15 18:00 
SuggestionInteresting Pin
Kent K21-Apr-15 3:19
professionalKent K21-Apr-15 3:19 
GeneralRe: Interesting Pin
Dr Gadgit27-Apr-15 2:56
MemberDr Gadgit27-Apr-15 2:56 
QuestionCool, but one small problem.... Pin
Mike Baldini17-Apr-15 9:44
professionalMike Baldini17-Apr-15 9:44 
AnswerRe: Cool, but one small problem.... Pin
Dr Gadgit17-Apr-15 11:25
MemberDr Gadgit17-Apr-15 11:25 
AnswerRe: Cool, but one small problem.... Pin
thund3rstruck23-Apr-15 10:54
Memberthund3rstruck23-Apr-15 10:54 
GeneralRe: Cool, but one small problem.... Pin
Dr Gadgit27-Apr-15 3:28
MemberDr Gadgit27-Apr-15 3:28 
GeneralRe: Cool, but one small problem.... Pin
Peter Shaw27-Apr-15 8:50
professionalPeter Shaw27-Apr-15 8:50 
GeneralRe: WinPCap Pin
Dr Gadgit28-Apr-15 1:01
MemberDr Gadgit28-Apr-15 1:01 
GeneralRe: WinPCap Pin
Peter Shaw28-Apr-15 1:07
professionalPeter Shaw28-Apr-15 1:07 
GeneralRe: WinPCap Pin
Dr Gadgit28-Apr-15 4:24
MemberDr Gadgit28-Apr-15 4:24 
GeneralRe: WinPCap Pin
Peter Shaw28-Apr-15 21:57
professionalPeter Shaw28-Apr-15 21:57 
GeneralRe: WinPCap Pin
Dr Gadgit29-Apr-15 4:25
MemberDr Gadgit29-Apr-15 4:25 
GeneralRe: WinPCap Pin
Peter Shaw29-Apr-15 5:43
professionalPeter Shaw29-Apr-15 5:43 
GeneralRe: WinPCap Pin
Dr Gadgit29-Apr-15 6:18
MemberDr Gadgit29-Apr-15 6:18 
GeneralRe: WinPCap Pin
Peter Shaw29-Apr-15 6:36
professionalPeter Shaw29-Apr-15 6:36 
GeneralRe: WinPCap Pin
Dr Gadgit29-Apr-15 7:39
MemberDr Gadgit29-Apr-15 7:39 
GeneralRe: WinPCap Pin
Peter Shaw30-Apr-15 11:25
professionalPeter Shaw30-Apr-15 11:25 
GeneralRe: WinPCap Pin
Dr Gadgit1-May-15 6:58
MemberDr Gadgit1-May-15 6:58 
GeneralRe: WinPCap Pin
Peter Shaw2-May-15 22:09
professionalPeter Shaw2-May-15 22:09 

General General    News News    Suggestion Suggestion    Question Question    Bug Bug    Answer Answer    Joke Joke    Praise Praise    Rant Rant    Admin Admin   

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.

Posted 16 Apr 2015


42 bookmarked