1

00:00:00,420 --> 00:00:08,130

Hello, welcome, come back in this video, I'm going to show you how to use Iida as a debugger and



2

00:00:08,130 --> 00:00:09,910

also how to patch files.



3

00:00:10,920 --> 00:00:17,820

So going down with this cracked me, cracked me one along with the crazy one.



4

00:00:17,820 --> 00:00:22,110

That's the source code and put it in your folder.



5

00:00:22,110 --> 00:00:23,190

They call Cracked Me.



6

00:00:23,190 --> 00:00:24,420

Just create a new folder.



7

00:00:25,650 --> 00:00:33,690

And after you done that, you can try to run it and see what he does to open the new terminal here.



8

00:00:37,380 --> 00:00:44,850

And just run the creamy one, he asks you to enter key, so you enter anything you say.



9

00:00:44,850 --> 00:00:45,370

Sorry.



10

00:00:46,110 --> 00:00:49,470

So now I'm going to show you how to crack this.



11

00:00:49,470 --> 00:00:52,770

Crack me one using Eda's debugger.



12

00:00:53,610 --> 00:01:00,920

If you want to know what the creamy one Sasko looks like, you can open this in a text editor.



13

00:01:03,060 --> 00:01:11,250

So it is a simple program, has got a main function and two other functions success and feel he brings



14

00:01:11,250 --> 00:01:19,860

a problem and the key and ensconcing input and it in the integer variable called key in any comparison.



15

00:01:19,920 --> 00:01:25,440

The key keys to to determine if it is a success function, the print Congress.



16

00:01:26,430 --> 00:01:32,560

Otherwise you will call the feel function to print the sorry message and then he returns.



17

00:01:33,000 --> 00:01:34,290

So very simple program.



18

00:01:37,440 --> 00:01:40,440

So now let's open this in Ida.



19

00:01:42,320 --> 00:01:43,070

Prickling new.



20

00:01:44,170 --> 00:01:46,450

An open me one.



21

00:01:55,480 --> 00:02:05,710

So this is a very small program, so the entry point is here, here and Turkey printf here and here



22

00:02:05,720 --> 00:02:11,020

it Skåne, we see what the user enters and sees into verbal.



23

00:02:13,500 --> 00:02:23,450

And over here, he does a comparison of nine to one which you can convert to decimal, over here you



24

00:02:23,450 --> 00:02:31,250

can use a hajji as a shortcut, and then he's going to compare the value that the U.S. is to 237.



25

00:02:32,480 --> 00:02:36,250

Again, if it is, then this comparison is zero.



26

00:02:36,950 --> 00:02:43,070

When you say comparisons usually means that you would take X minus two, three, seven and you can resolve



27

00:02:43,070 --> 00:02:43,380

zero.



28

00:02:44,180 --> 00:02:50,570

So even if it's zero, zero can go to the left and you've been success.



29

00:02:51,260 --> 00:02:56,860

But if the user input something which is not to 237.



30

00:02:57,140 --> 00:03:02,060

So when you take X minus 237, you are not going to get zero.



31

00:03:02,930 --> 00:03:07,010

So in that case, Jumblat Zero will go to the right.



32

00:03:07,730 --> 00:03:09,070

And here you Greenfield.



33

00:03:10,130 --> 00:03:12,080

So now we can step through this.



34

00:03:12,870 --> 00:03:16,730

We can put a breakpoint here.



35

00:03:17,570 --> 00:03:18,880

So it put a break point.



36

00:03:19,520 --> 00:03:27,590

We can have two is a shortcut or we can go to debugger and go to the breakpoints and at break point.



37

00:03:29,510 --> 00:03:31,340

So now he has an breakpoint over here.



38

00:03:33,060 --> 00:03:33,630

So.



39

00:03:34,510 --> 00:03:37,920

Over here is a break point and then we can run into.



40

00:03:40,130 --> 00:03:41,570

And then he creates.



41

00:03:46,050 --> 00:03:53,670

OK, so now if you go to the command line, you will see he has printed front and Turkey, so just about



42

00:03:53,670 --> 00:03:57,210

anything he won't show presenter.



43

00:03:58,820 --> 00:04:01,940

And now he has stopped our breakpoint over here.



44

00:04:03,050 --> 00:04:11,150

So at this point here, you're sorry, but he asked me to 37 amnesia's taken this value in years ago



45

00:04:11,150 --> 00:04:12,260

and made it to the G7.



46

00:04:13,160 --> 00:04:15,410

And he wrote this result, which is.



47

00:04:16,820 --> 00:04:21,740

So because it is not zero, this arrow is bringing, the Green Arrow is blinking.



48

00:04:22,130 --> 00:04:28,340

And Miss Green go to the right and call the full message so you can click on the message to see what



49

00:04:28,340 --> 00:04:28,700

he does.



50

00:04:29,480 --> 00:04:34,520

So if you put string, Solley escaped and go away.



51

00:04:35,180 --> 00:04:36,770

But we don't want anything to go in here.



52

00:04:36,770 --> 00:04:37,910

You want to go to left.



53

00:04:38,510 --> 00:04:41,960

So Levius, you were called a success function.



54

00:04:41,970 --> 00:04:45,910

So we double click on this and as I said, function postering Congress.



55

00:04:45,920 --> 00:04:48,180

So this is what you want to skip.



56

00:04:49,270 --> 00:04:51,470

So how do we reverse this to me?



57

00:04:51,500 --> 00:04:55,070

Go to the left to reverse years, to go to the next.



58

00:04:56,030 --> 00:05:06,410

You can assemble Jersey here changes, which is not zero to become Anjum zero, so to do that and be



59

00:05:06,410 --> 00:05:16,700

selected and then you go to edit, come down to that program and then click on Assemble here we just



60

00:05:16,710 --> 00:05:19,490

change Channel zero to become zero.



61

00:05:19,510 --> 00:05:22,690

This is how we reverse the jump in.



62

00:05:22,700 --> 00:05:27,480

A number of bytes required for both zero and zero are the same.



63

00:05:27,980 --> 00:05:30,940

So it's quite safe to do the embossing here.



64

00:05:31,580 --> 00:05:34,940

He will not overwrite any of the subsequent code.



65

00:05:35,720 --> 00:05:36,590

So click OK.



66

00:05:37,830 --> 00:05:42,720

Now closes, so now you can step through this by pressing every.



67

00:05:43,700 --> 00:05:54,770

So either that or you go to debugger and we're here, step over so cocky, so I step over to the left.



68

00:05:54,920 --> 00:06:00,710

So now we're here and he's going to move to zero to the exit and then it's going to cost us.



69

00:06:00,860 --> 00:06:02,760

So let's step over again pressing it.



70

00:06:04,770 --> 00:06:05,890

I it again now.



71

00:06:05,970 --> 00:06:10,910

So the court success going take a look and see the Congress.



72

00:06:11,820 --> 00:06:12,240

All right.



73

00:06:12,540 --> 00:06:15,510

So we have already managed to reverse this.



74

00:06:16,530 --> 00:06:18,700

So now we can run all the way.



75

00:06:19,140 --> 00:06:28,010

Either you click on this or you press debugger, go to F name, continue the process so you run to completion.



76

00:06:29,550 --> 00:06:32,920

And now Lady Gaga has done because the program has completed.



77

00:06:33,720 --> 00:06:43,220

So now if you want to bench your file, this is a father you want to pitch claim you won so far.



78

00:06:43,950 --> 00:06:46,500

We created the program.



79

00:06:48,530 --> 00:06:49,700

Patches to input for.



80

00:06:51,680 --> 00:06:56,860

And this is a fight you're going to fetch my we want to create a backup circling on this great backup



81

00:06:57,260 --> 00:07:03,920

so they can finally have a ascencion here you go in passion is fire and create a backup.



82

00:07:04,550 --> 00:07:05,840

So the backup is important.



83

00:07:05,840 --> 00:07:09,170

In case you made a mistake, you have a here.



84

00:07:09,200 --> 00:07:12,950

We still have a copy of the file before he was patched.



85

00:07:13,220 --> 00:07:17,080

So let's test our Quami One Bashforth now and see what happens.



86

00:07:17,090 --> 00:07:21,440

Open the terminal here and come here and there.



87

00:07:21,820 --> 00:07:22,130

You



88

00:07:25,550 --> 00:07:29,280

enter any key, any prints, Congress.



89

00:07:29,300 --> 00:07:32,320

So you have successfully push this far.



90

00:07:32,750 --> 00:07:34,310

So I'm going to shoot another way.



91

00:07:34,790 --> 00:07:36,000

So let's close this now.



92

00:07:36,230 --> 00:07:37,500

Don't send me database.



93

00:07:40,090 --> 00:07:42,160

And then we did this on.



94

00:07:44,250 --> 00:07:47,100

And need to back to the origin of our.



95

00:07:50,850 --> 00:07:51,270

All right.



96

00:07:58,000 --> 00:08:01,270

New reopen the original file.



97

00:08:02,190 --> 00:08:08,520

All right, so now I'm going to show another way instead of reversing the jump.



98

00:08:08,820 --> 00:08:11,250

You can also tamper with the register.



99

00:08:13,230 --> 00:08:18,630

OK, this time we are going to do something different instead of putting a brick here that is put a



100

00:08:18,630 --> 00:08:22,230

brick somewhere else, probably all we can put a brick here.



101

00:08:22,230 --> 00:08:27,290

So we have to turn this run to that compensation plan.



102

00:08:27,430 --> 00:08:27,930

Yes.



103

00:08:28,380 --> 00:08:30,680

OK, let's go and check the output.



104

00:08:31,290 --> 00:08:40,890

So the US and Turkey, so just to anything and press enter and now he's waiting for us at a break point



105

00:08:41,310 --> 00:08:42,040

over here.



106

00:08:43,110 --> 00:08:44,290

So this is a break point.



107

00:08:44,850 --> 00:08:47,390

So now he's going to do a comparison.



108

00:08:48,330 --> 00:08:48,920

Yes.



109

00:08:48,930 --> 00:08:50,210

In nine to one each.



110

00:08:51,060 --> 00:08:57,900

So here we see currently the value is not the same as nine to unhitch.



111

00:08:58,740 --> 00:09:02,030

So he would take X minus 91 here.



112

00:09:02,040 --> 00:09:03,150

He would not have zero.



113

00:09:04,120 --> 00:09:12,030

So if you want to make sure that he X minus nine to one, which is zero, we can either change the value



114

00:09:12,030 --> 00:09:15,140

here or change the register to nine to one.



115

00:09:16,180 --> 00:09:16,470

Right.



116

00:09:16,590 --> 00:09:18,650

So this is how comparison works here.



117

00:09:18,700 --> 00:09:25,740

We are going to change the value here to nine to one double click on the register and then it changes



118

00:09:25,740 --> 00:09:26,560

to a nine to.



119

00:09:28,300 --> 00:09:30,130

Nine to one,



120

00:09:33,080 --> 00:09:40,030

right, so now when he does a comparison, yes, minus nine to one, which you would take these nine



121

00:09:40,030 --> 00:09:43,180

to one, minus nine to one endeavor Gifu zero.



122

00:09:43,780 --> 00:09:48,070

So zero will go to the left and show success.



123

00:09:48,190 --> 00:09:49,420

He said go to the right.



124

00:09:50,500 --> 00:10:00,370

OK, let us try now press Efate Stepanova, see how it is going to go to the left because the hero is



125

00:10:00,370 --> 00:10:03,460

blinking and through enough he went to the left.



126

00:10:05,400 --> 00:10:08,620

Now, he has shown the success message, going to check it out.



127

00:10:09,110 --> 00:10:09,660

Congrats.



128

00:10:10,160 --> 00:10:14,760

OK, so this is how he can modify the register itself during runtime.



129

00:10:15,600 --> 00:10:16,850

But this is not pitching.



130

00:10:16,860 --> 00:10:19,030

This is just modifying the register value.



131

00:10:19,860 --> 00:10:28,320

OK, so these are two ways in which you can modify the behavior of a program using debugger during runtime



132

00:10:28,890 --> 00:10:30,570

or there's not a thing I want to show you.



133

00:10:31,610 --> 00:10:32,830

Let's start this now.



134

00:10:33,750 --> 00:10:38,760

You can also do more than just modify or reverse terms.



135

00:10:38,760 --> 00:10:45,230

You can also delete execution of a Russian user, has to really have to hear.



136

00:10:45,270 --> 00:10:53,910

So, for example, if you don't want this thing to happen, you can just remove this by replacing these,



137

00:10:53,950 --> 00:10:54,990

you know, operation.



138

00:10:55,960 --> 00:10:56,260

Right.



139

00:10:56,310 --> 00:11:01,410

But to do that, you need to count how many bytes you need to substitute if no abberation.



140

00:11:02,250 --> 00:11:06,180

So let's convert to linear view the moving instruction.



141

00:11:06,570 --> 00:11:08,430

You need to see how many advisee uses.



142

00:11:08,430 --> 00:11:10,790

So good options, General.



143

00:11:11,550 --> 00:11:13,920

And here she was, 16.



144

00:11:14,760 --> 00:11:17,390

OK, so then you can see the.



145

00:11:18,600 --> 00:11:25,330

So this instruction Russian X followed by this address value in this address takes up three bytes.



146

00:11:25,830 --> 00:11:33,940

So if you're doing this instruction to happen, we can use this method and then.



147

00:11:35,860 --> 00:11:43,000

Changes through base to nine zero nine zero nine zero through the program, changed by.



148

00:11:44,670 --> 00:11:52,530

So this this by it'd be four or five efore, it'd be four or five efore, you can change into a nine



149

00:11:52,530 --> 00:11:54,570

zero nine zero nine zero.



150

00:11:56,040 --> 00:12:04,950

So I deleted sevice and I replaced your nine zero nine zero nine zero nine zero is no operation.



151

00:12:04,950 --> 00:12:07,160

NLB So now you take a look.



152

00:12:10,540 --> 00:12:14,420

I remove the instruction and replace it in operation.



153

00:12:14,920 --> 00:12:22,120

So this is an idea you can perform in Saige, you can convert or remove any kind of instruction you



154

00:12:22,120 --> 00:12:22,390

want.



155

00:12:22,960 --> 00:12:29,140

The important thing is he has it must be exactly the same number of bytes so that you will not disturb



156

00:12:29,380 --> 00:12:31,180

the instruction that comes after it.



157

00:12:31,540 --> 00:12:33,550

Otherwise you will cost programming failure.



158

00:12:34,680 --> 00:12:37,640

OK, so these are the only things you can do.



159

00:12:37,720 --> 00:12:41,210

So I'm just going to control them to put it back.



160

00:12:41,560 --> 00:12:42,910

That's all for this video.



161

00:12:43,060 --> 00:12:44,140

Thank you for watching.