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[Steake]

Originally Posted by iPhoneDevelopment

Hi,

I have taken two of the methods from here and combined them to make it twice as hard to crack my app (I understand the argument about there always being a way around whatever protection is put in place, but it is nice to at least feel like you are helping stop your app being cracked):

-(void) crackCheck { 
NSString* bundlePath = [[NSBundle mainBundle] bundlePath];
NSString* path = [NSString stringWithFormat:@"%@/Info.plist", bundlePath];
NSString* path2 = [NSString stringWithFormat:@"%@/AppName", bundlePath];
NSDate* infoModifiedDate = [[[NSFileManager defaultManager] fileAttributesAtPath:path traverseLink:YES] fileModificationDate];
NSDate* infoModifiedDate2 = [[[NSFileManager defaultManager] fileAttributesAtPath:path2 traverseLink:YES] fileModificationDate];
NSDate* pkgInfoModifiedDate = [[[NSFileManager defaultManager] fileAttributesAtPath:[[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:@"PkgInfo"] traverseLink:YES] fileModificationDate];

if(fabs([infoModifiedDate timeIntervalSinceReferenceDate] - [pkgInfoModifiedDate timeIntervalSinceReferenceDate]) > 600) {	
	if (gameState == kGameStateRunning) {
		gameState = kGameStatePaused;
		if (crackedProgress.hidden) {
			crackedProgress.hidden = NO;}
		if (crackedAlert.hidden) {
			crackedAlert.hidden = NO;}
	}
}
if(fabs([infoModifiedDate2 timeIntervalSinceReferenceDate] - [pkgInfoModifiedDate timeIntervalSinceReferenceDate]) > 600) {	
	if (gameState == kGameStateRunning) {
		gameState = kGameStatePaused;
		if (crackedProgress.hidden) {
			crackedProgress.hidden = NO;}
		if (crackedAlert.hidden) {
			crackedAlert.hidden = NO;}
	}
} 
	BOOL fileExists = [[NSFileManager defaultManager] fileExistsAtPath:(@"%@/_CodeSignature", bundlePath)];
	if (!fileExists) {
		if (gameState == kGameStateRunning) {
			gameState = kGameStatePaused;
			if (crackedProgress.hidden) {
				crackedProgress.hidden = NO;}
			if (crackedAlert.hidden) {
				crackedAlert.hidden = NO;}
		}
	}
	BOOL fileExists2 = [[NSFileManager defaultManager] fileExistsAtPath:(@"%@/CodeResources", bundlePath)];
	if (!fileExists2) {
		if (gameState == kGameStateRunning) {
			gameState = kGameStatePaused;
			if (crackedProgress.hidden) {
				crackedProgress.hidden = NO;}
			if (crackedAlert.hidden) {
				crackedAlert.hidden = NO;}
		}
	}
	BOOL fileExists3 = [[NSFileManager defaultManager] fileExistsAtPath:(@"%@/ResourceRules.plist", bundlePath)];
	if (!fileExists3) {
		if (gameState == kGameStateRunning) {
			gameState = kGameStatePaused;
			if (crackedProgress.hidden) {
				crackedProgress.hidden = NO;}
			if (crackedAlert.hidden) {
				crackedAlert.hidden = NO;}
		}
	}
}

I then halt the game and show an alert and a fake progress bar saying that the device's data is being sent to Apple... that should make them delete the cracked app :P.

Just one question.. is there any way to test the protection without cracking it and putting on a jailbroken phone (not being something I want to do)?

Thanks

Cam

My app congratulates the user on actually cracking it... Because i'm cool