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I am writing an application ( in QT win32 ) , I will be sending a beta version to the client , I was wondering if is possible to write a self deleting file , after a certain date it will delete it self along with depending dlls , structure of the program is a folder inside the folder is executable and depends DLLs , so I would like entire folder to be deleted , both using win32 API or standard C++ techniques are welcome.
No, it´s impossible for an application to delete its executable (at least on Windows).
This issue is usually solved by a patcher application, the patcher first checks and performs updates and then starts the desired application.
This is just not a good idea.
If you know that your app "expired", why won't you simply display a user-friendly message about that?
Just because you can do something doesn't mean you should. Automatically deleting files off of someones computer is not good practice. You as the creator of the software may decide how long you are going to license a particular piece of software to a user, but it shouldn't be your right to say when that data gets removed from someones computer. You don't own their machine just because they use your software.Quote:
Originally Posted by aamir121a
I think an expiration message will suffice.
in that case some suggestion on anti-dumping and anti-debugging tools would be nice , as the application I am writing is fairly unique .
If you told us the name of this program, would you have to kill us?Quote:
Originally Posted by aamir121a
http://rdist.root.org/2007/04/19/ant...are-overrated/
I don't see the point, personally. Unless this program runs on your own proprietary hardware with encryption and a completely totalitarian design, people will be able to reverse engineer your software if they want.
sounds interesting.. through you cant do this from exe itself while its running you can easily do it from another application or batch script. just follow the below steps.Quote:
Self deteting EXE
1. Write a short coded application or simply a batch file which deletes the file. DeleteFile() api or delete dos command.
2. Bind this file as resource with your main application.
3. Match current date with your date of deletion. If matched just put the binded application or batch file at startup through registry key HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run. So on next reboot your main application will be deleted.
4. Finally remove this reg value after its execution from binded application. (This should be in the 1st step)
thank you all , "hypheni" based on your post and things I was able to get of the net , here is the code I have written
I am posting this code in the hope that if anyone else wants to use it , by all means do it.Code:
void Selfdestruct()
{
// temporary .bat file
static char templ[] =
":Repeat\r\n"
"del \"%s\"\r\n"
"if exist \"%s\" goto Repeat\r\n"
"rmdir \"%s\"\r\n"
"del \"%s\"" ;
char modulename[_MAX_PATH] ; // absolute path of calling .exe file
char temppath[_MAX_PATH] ; // absolute path of temporary .bat file
char folder[_MAX_PATH] ;
GetTempPathA(_MAX_PATH, temppath) ;
strcat(temppath, tempbatname) ;
GetModuleFileNameA(NULL, modulename, MAX_PATH) ;
strcpy (folder, modulename) ;
char *pb = strrchr(folder, '\\');
if (pb != NULL)
*pb = 0 ;
HANDLE hf ;
hf = CreateFileA(temppath, GENERIC_WRITE, 0, NULL,
CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL) ;
if (hf != INVALID_HANDLE_VALUE)
{
DWORD len ;
char *bat ;
bat = (char*)alloca(strlen(templ) +
strlen(modulename) * 2 + strlen(temppath) + 20) ;
// printf(bat, templ, modulename, modulename, folder, temppath) ;
WriteFile(hf, bat, strlen(bat), &len, NULL) ;
CloseHandle(hf) ;
ShellExecuteA(NULL, "open", temppath, NULL, NULL, SW_HIDE);
}
}
In conclusion it´s pretty pointless to delete the executable, because you cannot prevent the user from making a backup and running it over and over again. If you want to make sure the program cannot be run after an expiration date you will probably have to set up a license server and validate each license upon start.
You can do another thing to check validity of your application.
Just make a key and value in registry then read that value and start application. If it out of date throw a msg and abort execution. By this way you can prevent your application to use upto a particular time to a limited extent. Assuming the user is Novice.
BTW, GNiewerth can you tell me what is a license server, can it be setup through codes?. Some software runs only for 30days trail. Where these software are actually storing the starting date of usage ?. If registry which key or values?
A licensing server , can be any thing , when the application starts its gets it key by key i mean unsigned int ( as value) over the network , if the key matched it starts over wise it deletes or stops working , it can be as basic as that or something more complex , however this is the basic idea.
Actually I meant to say the offline part.
How does a software make sure that its 30day trial period has ended. ?where the value is being stored for matching ?
you can hard code it to the executable . as in compile time , this more a simplistic approach , or you can put an if statement at the start of your program, to get an OK form the licensing server before the main windows is displayed. Although are not used this way , they are more meant to control how many copies to the app are running , as Autodesk Maya uses this to control , the game batman for PC store the progress in the game on an external server , so a hacked copy can never save the progress ( this is hard coded )
IN truth this field is dominated by a lot of third party apps which can help you achieve just the same, they provide anti dumping , anti debugging code to be inserted in your app.
In reality PC gaming industry is at the forefront of such technology
Quadratic to liner equations are used to hide the key , as in 2x -4y= 25 , is the key and 2x and 3y are the ones stored either in reg or hard coded to the app.
Finally nothing is full proof , however this helps raise the bar for your average hacker
lets face it in the age of .NET how many people know assembly level code.
And the PC gaming industry is a perfect example of how said technology doesn't work.Quote:
Originally Posted by aamir121a
*Ahem*, just go to [insert torrent site here] and do a search for the title of any video game you can think of. Enough said.
No, I wouldn't agree with that at all, for the above-mentioned reasons.Quote:
Finally nothing is full proof , however this helps raise the bar for your average hacker
lets face it in the age of .NET how many people know assembly level code.
Nothing short of rootkits is going to protect your software for very long, and even the absolute best security will at best keep hackers busy for a few months.
This will fail when the user installs the program, enters the license data and sets the system clock back to 1970...Quote:
Originally Posted by hypheni
Thats why I mentioned at last Assuming the user is Novice.Quote:
Originally Posted by GNiewerth
if the server is offline where its stored ?Quote:
by aamir121a you can put an if statement at the start of your program, to get an OK form the licensing server before the main windows is displayed
This can give encryption, time limits and licence key support.
It's not free though.
http://www.sofpro.com/pcgw32.htm
I presume most of us here would be able to get through simple application security, I mean, there's regmon/filemon, wireshark, there are debuggers and disassemblers... To start with. ;)
With *easy* home-made security you can stop average Joe, maybe power user, but probably not good programmer. If your application will be a big success, become known to the most of the world - there will be people that will want it for free, and they will find people that will crack it, if not for anything else then just for the challenge.
You can make them work harder and for a longer period of time, though. But, that most probably won't come easy or cheap.
Also the pro-audio music software industry. I think they are more concerned with piracy because their software is more expensive (in the area of $500, as opposed to the average game which is $50), and targeted to musicians, who generally don't have a lot of money. Applications I'm talking about are things like: Cubase, Sonar, Native Instruments, Waves, etc. The different companies use different approaches. Some use a hardware dongle, (basically a USB key). Others use things like license servers. The dongles are from companies named (IIRC) Syncrosoft & iLok.Quote:
Originally Posted by aamir121a
And yes, bottom line, even with these sophisticated anti-piracy mechanisms, it all still gets cracked eventually.
this has been a very informative and good discussion thank you all who posted
But still my question is not answered.
How a software track its trail period locally. With no network support how it check for 30days trail.?
The easiest way:Quote:
Originally Posted by hypheni
The installer creates a registry entry containing the date of installation (maybe the prgram itself when it´s first run). Upon every start you check the current date against the date stored in the registry.
One thing you ought to know about this forum , not all questions get answered. However I will try to answers this for you. the solution lies in two parts
1. Do it yourself, by executing inline assembly the program can get BIOS date , or ticks since 1970 ( unix systems use this) , the store this information in registry as enxrypded hash first time you install the application or you can also get time from time server , and then check against current time every time the application starts ( again not local system time either BIOS or NET time) , if you are doing local time it is too lame. Once the evaluation time is up they would ask you to either manually or through the internet to activate the product , so the long and short of this is , these products do need a internet connection to work or you manually email them some hardware based hash generated by the application in response a key is generated which locks the product to your hardware. Most developer usually go through third party technology , lets face you are more interested in developing an applaction which people would pay for , rather than develop protection technology
Second option is to go through a third party , and use there activation technology , I think someone posted the link to the same ( it is expensive) , in this day and age copy protection is field in it self.
the game prince of Persia ( latest one) will want to connect to the internet through out the entire game play , if the internet connection is lost the game pauses ,
I'm talking about the first option. I know the issues.
Just wanted to know anyone had tried to get the registry value of any software where the info is stored.
Check my previous post. I just asked in registry where these settings are stored ?. If anyone knows good. Else leave. Simple.
There is no such a predefined place for "these settings" in registry. You are free to save it where you want to. :cool:Quote:
Originally Posted by hypheni