"EditPlus is Internet-ready 32-bit text editor for Windows 95/98 and Windows NT 4.0 or higher.  It is not only a good replacement for Notepad, but also it has much more powerful features for web-page authors and programmers."
 

About this protection system

 
Registration is via selecting the 'Help' menu option the choosing the 'Enter Registration Key' selection. Here you will be asked to enter:-

User Name          :
Registration Key :

The registration code is based on what you type in for your name/handle, it is Case sensitive, so entering The Sandman will produce a different registration key than if you had typed in the sandman and the resulting registration key appears to always contain a total of 17 characters.
 
Once registered, the program saves the registration info within your System Registry file, at:
 
HKEY_LOCAL_MACHINE\SOFTWARE\ES-Computing\EditPlus\1
 
Creating these two entries:-
 
Install         93 00 00 00
License     DB 89 29 18 F6 5D 01 5E 78 9C E3 0E C9 4D
                  CC 33 70 B2 B0 70 73 72 31 D1 75 74 74 B4
       34 71 B6 30 03 00 80 08 07 FF
 
Some of these bytes might be different for you if these bytes were generated from the registration key entered into Edit Plus.
          

The Essay

     
After learning the 'memory echo' method to crack programs I've so far been able to crack the last three programs I've looked at one after another using this technique regardless of how they were coded.

EditPlus, while still cracked with this technique required a little massaging of it's code to get it to work but nothing too drastic.  Since this was the first time I was faced with this particular situation of massaging the code to make it do what I wanted it to do it's worth explaining the process from start to finish in detail.
 
Right, run up EditPlus and go into the Registration screen, via 'Help' then 'Enter Registration Key...".  Type in a name or handle and for the actual regkey just type an anything that comes to mind but DON'T press the 'OK' button just yet.
 
We're going to first tell Softice to break on any requests to use the MessageBoxA routine, so press 'CTRL-D' then type: bpx messageboxa
 
Since this is a 32-bit application it will be fair to say it will use 32-bit system functions which messageboxa is, rather than it's 16-bit counterparts like messagebox.  The difference is the 'a' at the end of the function name, the 'a' signifies that it is a 32-bit function.
 
Press x to leave Softice and now you press the 'OK' button to have EditPlus check our registration key.  Once Softice breaks, press the F11 key once. You should now be at this interesting piece of code:-
 
:00486527 8B4F1C                  mov ecx, dword ptr [edi+1C]
:0048652A 8B55FC                  mov edx, dword ptr [ebp-04]
:0048652D FF750C                  push [ebp+0C];Save Messagebox parameters
:00486530 FF7278                  push [edx+78];Save Messagebox parameters

:00486533 FF7508                  push [ebp+08];Save memory pointer to
                                               ;to the beggar off message

:00486536 51                      push ecx     Save Messagebox parameters
:00486537 FF15FCFD4C00            Call dword ptr [User32!MessageBoxa]
:0048653D 8BF8                    mov edi, eax ;We land here
:0048653F 891E                    mov dword ptr [esi], ebx
:00486541 837DF800                cmp dword ptr [ebp-08], 00000000
:00486545 740B                    je 00486552
 
Before the 'Beggar off cracker' message can be displayed the system function 'MessageBoxA' requires certain information to be placed onto the 'Stack' (an area of memory reserved for short-time passing of parameters to functions, which in this case for our MessageboxA function) so that it knows how to display the messagebox when it's shown on your screen. The kind of information required before the messagebox can be shown is:-
 
What type of message box to use, how many buttons (like 'ok','yes','no','cancel' it will have, what text to display within it and what title the messagebox will have.  The order of these parameters passed onto the STACK is very important so we must maintain this same order when we start to massage the code.
 
The bit we're interested in is the text that will be displayed in this messagebox, in this case the 'Beggar off cracker' message. But before we can start altering this section of code we must understand how it works, so  type  bc * to clear away any breakpoints we may still have in Softice then type bpx 0048652A then x to leave softice.  We are going to get Softice to break before the program generates our message box so we can see what information is being passed to it.  Once more we're back in the Edit Plus Registration screen. Click the 'OK' button again and once again Softice breaks and we're back in the Edit Plus code, only this time just before our 'Beggar off cracker' is shown.
 
Right, Softice stops on this line:-
 
 

Lets see what the state of some of those registers are.

EBP = 72F304  *Address will  be slightly different on your puter *

For our *crack* we need to check on the ebp register, to see if our 'real' serial no is close by..

So type: d ebp

Yep, our real serial number is close by, so if all we wanted was to grab the serial number and use it to register the program with then that would be a lame thing to do, especially when we can do much more here. While we are here try and work out the EXACT memory location of the beginning of our our serial number, this is important because from this address we can work out the displacement value for our ebp register for when the time comes to use it.
 
Once you have the EXACT memory address of the serial number we now have to work out the displacement value so that we can find this location every time the program is run, regardless of where in memory the program is.

Example: Here's what I mean.
 
On my computer the memory location of the serial number was found at: 0072F418 and the value in the ebp register was 0072F3D4.  To get the displacement value all I did was type:

? 72F418-ebp

Which gave me the answer of 44h.  The question mark tells Softice to work out the expression, in this case a simple subtraction (serial No address) of one value from another (address of the ebp register). Hope this makes sense?.
 
The next register we will look at is the ECX register, because the program by passed the line:

:00486527 8B4F1C                  mov ecx, dword ptr [edi+1C]

when it jumped to this block of code.

OK, the Register ECX has been pre-loaded with the address 00000???, the question marks represent a three digit number that varies each time the program is run. However, it will ALWAYS point a memory location that contains the following three bytes: 00 00 03
 
Lets now dissect the what happens before the MessageBoxA routine is called:

Press F10 once, we have just executed this instruction:- mov edx, dword ptr [ebp-04]
 
Register EDX has now been given a memory address 'pointed' to by our ebp register with a displacement of four bytes.  To understand this we can do the following:-

Type d ebp-4

Look in Softice's hex code window, can you see the first four bytes, these four bytes
[38 20 4A 00]  make up a memory address that the MessageBoxA routine will use when it's asked to create the messagebox.  These four bytes are in stored in REVERSE ORDER, so to get the actual memory location they represent we reverse this order so that they read: 004A2038, don't blame me for this confusion, blame Intel!
 
Now press the F10 key once more..

We have just executed this instruction: push [ebp+0C]
 
This instruction is now pushing onto the STACK a memory location that the MessageBoxA function will read as a numerical value that represents what type of Icon this messagebox will use when it display's our messagebox. We are not concerned with what Icon is shown so lets proceed onto the next instruction.  Press the F10 key once more..

We have just executed this instruction: push [edx+78]

We can use the same procedure as before to find out what's being saved onto the STACK by typing d edx+78 then typing D followed by (in reverse order) the first four bytes shown in the hex code window. If you've done this properly you will see the text "Edit Plus"

This will be used for the Message Box's Title.
 
Now press the F10 key once more.
 
We have just executed the following instruction. push [ebp+08]
 
Our friend the ebp register again, only this time using a displacement value of +8 bytes.
 
Lets type d ebp+8 and then using the four bytes shown in the hex code window (make sure to reverse the order)  type d ????????, replace the question marks with the four bytes shown in the hex code window.. Example, if you see the bytes 3C A7 B8 00 then you will need to type d 00B8A73C
 
Bingo!, we've found the instruction that 'point's to the memory location of where our 'Beggar off cracker' text is located. So what do we do about it.
 
Well what I did was to overwrite the instruction push [ebp+08] and replace it with:
LEA EAX,[EBP+44] which fitted in exactly.  Notice I'm using the ebp register with our magical 44h displacement number, which we know is where our serial number is.
 
If you try and run these sequence of instructions by trying to enter a serial number into EditPlus then NO message box will be shown!!. We can use Softice to go over these instructions before it hits the Call User32!MessageBoxA and everything 'looks' ok, but we're STILL missing something before our *crack* will work.. Can you *see* what's missing?.
 
:00486527 8B4F1C                  mov ecx, dword ptr [edi+1C]
:0048652A 8B55FC                  mov edx, dword ptr [ebp-04]
:0048652D FF750C                  push [ebp+0C];Save Messagebox parameters
:00486530 FF7278                  push [edx+78];Save Messagebox parameters

:00486533 FF7508                  lea eax,[ebp+44];eax =loc of Serial No
:00486536 51                      push ecx     ;Save Messagebox parameters
:00486537 FF15FCFD4C00            Call dword ptr [User32!MessageBoxa]
:0048653D 8BF8                    mov edi, eax ;We land here
:0048653F 891E                    mov dword ptr [esi], ebx
:00486541 837DF800                cmp dword ptr [ebp-08], 00000000
:00486545 740B                    je 00486552

Yep, we haven't pushed the memory location of our serial number onto the STACK, so the MessageBoxA function can't find it, so the MessageBoxA function gets aborted.
 
What we need to do is insert a PUSH EAX instruction before the Call [User32!MessageBoxA] and that will cure this problem, but look, there's no room to insert this 1 byte instruction. Wish I Knew more Assembler now, might then have found another Assembler instruction that not only gets the memory location of our serial number but also push's this value on the STACK in one go!.

Not wanting to give up there seemed only one more course of action left to me, and that was to massage the code a little, so I checked what instructions got executed after the call to the MessageBoxA routine and found that the cmp dword ptr [ebp-08], 00000000 instruction always resulted in the je 00486552 being 'set' to jump. Hmm, in that case we can afford to 'lose' this instruction and then change the je 00486552 to jmp 00486552 instead!.
 
Let's now re-write this section of code so that it will always now show the 'real' serial number when we get it wrong:-
 
:0048652A 8B55FC                  mov edx, dword ptr [ebp-04]
:0048652D FF750C                  push [ebp+0C]
:00486530 FF7278                  push [edx+78]
:00486533 8D4544                  lea eax,[ebp+44];eax =loc of Serial No
:00486536 50                      push eax     ;Save it to the stack
:00486537 51                      push ecx
:00486538 FF15FCFD4C00            Call dword ptr [User32!MessageBoxA] 
:0048653E 8BF8                    mov edi, eax ;We land here
:00486540 891E                    mov dword ptr [esi], ebx
:00486542 90                      Nop    ;fill in empty space
:00486543 90                      Nop    ;fill in empty space
:00486545 EB0B                    jmp 00486552
 
Job Done.....
 

The 'Crack'

 
Load up editplus.exe into your favorite hex editor and SEARCH for the hex string: "8B55FCFF750CFF72"

00085910 83F80477 04804D0C 30E80AF5 0000B900 ...w..M.0.......
00085920 00000085 FF74038B 4F1C8B55 FCFF750C .....t..O..U..u.
00085930 FF7278FF 750851FF 15FCFD4C 008BF889 .rx.u.Q....L....
00085940 1E837DF8 00740B6A 01FF75F8 FF157400 ..}..t.j..u...t

Now REPLACE the following HIGHLIGHTED bytes with:
 
00085910 83F80477 04804D0C 30E80AF5 0000B900 ...w..M.0.......
00085920 00000085 FF74038B 4F1C8B55 FCFF750C .....t..O..U..u.
00085930 FF72788D 45445051 FF15FCFD 4C008BF8 .rx.EDPQ....L...
00085940 891E9090 90EB0B6A 01FF75F8 FF157400 .......j..u...t.
 
 

Final Notes

 
This was a good *crack* I feel, although it's not always good practice to change the target's code as much as I have done here, because if your not careful it could bring about unforeseen problems later. However, I've tested this patch a number of times under Softice and have made sure I haven't messed up any of the registers that might be needed by the program once it has completed the job of creating a message box.
 
Could this patch have been any other way without having to massage the code?
        
My thanks and gratitude goes to:

Fravia+ for providing possibly the greatest source of Reverse Engineering
knowledge on the Web.
 
+ORC for showing me the light at the end of the tunnel.

 

Ob Duh

 
Do I really have to remind you all that by buying and NOT stealing the software you use will ensure that these software houses will continue to  produce even *better* software for us to use and more importantly, to continue offering even more challenges to breaking their often weak protection systems.
 
If your looking for cracks or serial numbers from these pages then your wasting your time, try searching elsewhere on the Web under Warze, Cracks etc.