Symantec Visual café trial version 1.0 (1997)
(a very silly protection scheme on a very interesting target)


by A+heist
(6 November 1997, slightly edited by reverser+)


stupid
Most stupid protection
Courtesy of reverser's page of reverse engineering

Well, A+heist seems to prefer always easy protections and he is a lazy cracker indeed: he should at least have worked a little more on the 'this function is not allowed' scheme :-)
I was tempted NOT to publish this essay: the protection scheme is extremely banal, and targets with 'non sticking' trial limit are sitting ducks even for average doom users, really not worth of our time... yet A+heist 'didactic' is not bad (I like his comments to the code and the way he has reduced the code to the minimum) and, more relevantly, this target is very important for the FUTURE of our community, it seems clear (at least to some of us) that we are living the beginning of a great universal 'javation', therefore the sooner you'll learn how to program (and how to crack :-) in Java, the better.

Symantec Visual café trial version 1.0 (1997)
by A+heist, november 1997

Here you go with a very silly protection scheme on a very interesting 
target, which you can have almost for nothing, since in the last months 
it has been published on many magazines CD-ROMs. I'm lazy, and I'll 
crack this very quickly :)

A small explanation for all those that would like to begin their Java
career: Symantec Visual Café Pro, Borland JBuilder, Lotus BeanMachine, 
SunSoft JDK freeware and SunSoft JavaStudio (with JavaStar, JavaScope 
and JavaSpec) are considered the best developer tools around. Micro$oft's 
J++ is NOT considered a good tool (besides: it's good netiquette to 
avoid any Micro$oft product independently from its intrinsic value, for 
reasons that should be obvious for the readers of the essays).

Our target, Visual Café (Trial version 1.0, 1997) is only an update 
of the 1996 kit. You'll crack it here and use it to 'get the feeling',
then you'll switch to Visual café Pro, let's hope that Symantec will 
soon release that as well with another silly protection scheme. 
Nice thing in our target is that you get the Sun JDK 1.02 INSIDE it, and 
that it carries all necessary javaAPI helpfiles within :)  

OK, let's crack this together in less than one minute! 
- start target, 
- run target, 
- set time to 1999: "Your trial version has expired",
- back to now: works again (no sticky flag setting then: a 
  really easy one) 
- Finetuning the OS date you will notice a MSgBox saying 
  that "you have only 4/3/2/1 day(s) left"
- Disassemble target, get dead listing
- Search inside your editor...

Here you are:

Conditional jump here from 004126BD
:004126F2 68AC454A00              push 004A45AC       ;->".java"
:004126F7 8D8DE4F6FFFF            lea ecx, dword ptr [ebp+FFFFF6E4]
:004126FD E832A10500              call 0046C834
:00412702 8D8DE4F6FFFF            lea ecx, dword ptr [ebp+FFFFF6E4]
:00412708 E877A30500              call 0046CA84       ;get days left
:0041270D 89C3                    mov ebx, eax        ;save days left
:0041270F 83F8FF                  cmp eax, FFFFFFFF   ;check days left
:00412712 7404                    je 00412718         ;beggar off: -0
:00412714 85DB                    test ebx, ebx       ;0=beggar off
:00412716 7533                    jne 0041274B        ;else check how many

:beggar_off
:00412718 6AFF                 push FFFFFFFF
:0041271A 6A00                 push 00000000
:0041271C 6821290000           push 00002921    ; "Your trial version has expired
:00412721 E8C6EB0800           Call 004A12EC    ; SFC42.SFC42:NoName0537
:00412726 C745FCFFFFFFFF       mov [ebp-04], FFFFFFFF
:0041272D 8D8DB0F6FFFF         lea ecx, dword ptr [ebp+FFFFF6B0]
:00412733 E86AED0800           Call 004A14A2    ; SFC42.SFC42:NoName0610
:00412738 31C0                 xor eax, eax     ; eax=FALSE
:0041273A 8B4DF4               mov ecx, dword ptr [ebp-0C]
:0041273D 64890D00000000       mov dword ptr fs:[00000000], ecx
...       pop all
:0041274A C3                   ret          ;expired, beggar off

:from 00412716(C) ;not expired: how many days left?
:0041274B 83FB05              cmp ebx, 5       ;d'you have 5?
:0041274E 7D5E                jge 004127AE     ;more than 4: go and use it
:00412750 8D8DF8F7FFFF        lea ecx, dword ptr [ebp+FFFFF7F8]
:00412756 E829ED0800          Call 004A1484     ;SFC42.SFC42:NoName0605
... irrelevant code
:00412777 50                  push eax
:00412778 6820290000          push 00002920   ; "You have only %1 days left in your trial period."
:0041277D 8D85F8F7FFFF        lea eax, dword ptr [ebp+FFFFF7F8]
... irrelevant code
:004127AB 83C40C              add esp, 0000000C

from 0041274E(C), more than 5 days
|
:004127AE 8D8D08F8FFFF            lea ecx, dword ptr [ebp+FFFFF808] 
...happy work, good nice cracker

Well, I don't believe you need anything at all more than this.
I have done the following: I have substituted 
the FIRST check of the days left:

:0041270F 83F8FF        cmp eax, FFFFFFFF   ;check days left
:00412712 7404          je 00412718         ;beggar off: -0

with a 'fixed' day_left value greater than 4:

:0041270F BB06000000    mov ebx, 00000007   ;7 days left eternally!  

And that's all, of course: now our target will 'believe' for the 
eternity that we still have a week trial. 
Why 7 days and not many more? Because 
1)	7 is enough to avoid any nag screen
2) 	+ORC said somewhere something like 'never never maximize 
        our patching values uselessly', and I'm a good student :) 

We can now use this for a long while... yet there is another 
protection scheme (sort of :) inside:   
  
:nobody seems to call this snippet  
:00416627 6AFF                    push FFFFFFFF
:00416629 6A00                    push 00000000

* Possible Reference to String Resource ID=10530: "This function is not allowed in the trial version."
                                  |
:0041662B 6822290000              push 00002922

* Reference To: SFC42.SFC42:NoName0537, Ord:04AFh
                                  |
:00416630 E8B7AC0800              Call 004A12EC
:00416635 C3                      ret      

This corresponds to the 'Live Update' option in the help 
menu, and does not seem to me to be particularly important.
If you wanna crack this, you'll need to fire softice.

So that's it, hope you'll enjoy java, I believe we need many 
more crackers (and especially +crackers) on this :)

Enjoy! A+heist 1997
(c) A+heist 1997. All rights reversed
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